LCOV - code coverage report
Current view: top level - src/backend/optimizer/util - clauses.c (source / functions) Hit Total Coverage
Test: PostgreSQL 19devel Lines: 1573 1793 87.7 %
Date: 2025-10-02 06:18:21 Functions: 74 75 98.7 %
Legend: Lines: hit not hit

          Line data    Source code
       1             : /*-------------------------------------------------------------------------
       2             :  *
       3             :  * clauses.c
       4             :  *    routines to manipulate qualification clauses
       5             :  *
       6             :  * Portions Copyright (c) 1996-2025, PostgreSQL Global Development Group
       7             :  * Portions Copyright (c) 1994, Regents of the University of California
       8             :  *
       9             :  *
      10             :  * IDENTIFICATION
      11             :  *    src/backend/optimizer/util/clauses.c
      12             :  *
      13             :  * HISTORY
      14             :  *    AUTHOR            DATE            MAJOR EVENT
      15             :  *    Andrew Yu         Nov 3, 1994     clause.c and clauses.c combined
      16             :  *
      17             :  *-------------------------------------------------------------------------
      18             :  */
      19             : 
      20             : #include "postgres.h"
      21             : 
      22             : #include "access/htup_details.h"
      23             : #include "catalog/pg_class.h"
      24             : #include "catalog/pg_language.h"
      25             : #include "catalog/pg_operator.h"
      26             : #include "catalog/pg_proc.h"
      27             : #include "catalog/pg_type.h"
      28             : #include "executor/executor.h"
      29             : #include "executor/functions.h"
      30             : #include "funcapi.h"
      31             : #include "miscadmin.h"
      32             : #include "nodes/makefuncs.h"
      33             : #include "nodes/multibitmapset.h"
      34             : #include "nodes/nodeFuncs.h"
      35             : #include "nodes/subscripting.h"
      36             : #include "nodes/supportnodes.h"
      37             : #include "optimizer/clauses.h"
      38             : #include "optimizer/cost.h"
      39             : #include "optimizer/optimizer.h"
      40             : #include "optimizer/pathnode.h"
      41             : #include "optimizer/plancat.h"
      42             : #include "optimizer/planmain.h"
      43             : #include "parser/analyze.h"
      44             : #include "parser/parse_coerce.h"
      45             : #include "parser/parse_collate.h"
      46             : #include "parser/parse_func.h"
      47             : #include "parser/parse_oper.h"
      48             : #include "parser/parsetree.h"
      49             : #include "rewrite/rewriteHandler.h"
      50             : #include "rewrite/rewriteManip.h"
      51             : #include "tcop/tcopprot.h"
      52             : #include "utils/acl.h"
      53             : #include "utils/builtins.h"
      54             : #include "utils/datum.h"
      55             : #include "utils/fmgroids.h"
      56             : #include "utils/json.h"
      57             : #include "utils/jsonb.h"
      58             : #include "utils/jsonpath.h"
      59             : #include "utils/lsyscache.h"
      60             : #include "utils/memutils.h"
      61             : #include "utils/syscache.h"
      62             : #include "utils/typcache.h"
      63             : 
      64             : typedef struct
      65             : {
      66             :     ParamListInfo boundParams;
      67             :     PlannerInfo *root;
      68             :     List       *active_fns;
      69             :     Node       *case_val;
      70             :     bool        estimate;
      71             : } eval_const_expressions_context;
      72             : 
      73             : typedef struct
      74             : {
      75             :     int         nargs;
      76             :     List       *args;
      77             :     int        *usecounts;
      78             : } substitute_actual_parameters_context;
      79             : 
      80             : typedef struct
      81             : {
      82             :     int         nargs;
      83             :     List       *args;
      84             :     int         sublevels_up;
      85             : } substitute_actual_srf_parameters_context;
      86             : 
      87             : typedef struct
      88             : {
      89             :     char       *proname;
      90             :     char       *prosrc;
      91             : } inline_error_callback_arg;
      92             : 
      93             : typedef struct
      94             : {
      95             :     char        max_hazard;     /* worst proparallel hazard found so far */
      96             :     char        max_interesting;    /* worst proparallel hazard of interest */
      97             :     List       *safe_param_ids; /* PARAM_EXEC Param IDs to treat as safe */
      98             : } max_parallel_hazard_context;
      99             : 
     100             : static bool contain_agg_clause_walker(Node *node, void *context);
     101             : static bool find_window_functions_walker(Node *node, WindowFuncLists *lists);
     102             : static bool contain_subplans_walker(Node *node, void *context);
     103             : static bool contain_mutable_functions_walker(Node *node, void *context);
     104             : static bool contain_volatile_functions_walker(Node *node, void *context);
     105             : static bool contain_volatile_functions_not_nextval_walker(Node *node, void *context);
     106             : static bool max_parallel_hazard_walker(Node *node,
     107             :                                        max_parallel_hazard_context *context);
     108             : static bool contain_nonstrict_functions_walker(Node *node, void *context);
     109             : static bool contain_exec_param_walker(Node *node, List *param_ids);
     110             : static bool contain_context_dependent_node(Node *clause);
     111             : static bool contain_context_dependent_node_walker(Node *node, int *flags);
     112             : static bool contain_leaked_vars_walker(Node *node, void *context);
     113             : static Relids find_nonnullable_rels_walker(Node *node, bool top_level);
     114             : static List *find_nonnullable_vars_walker(Node *node, bool top_level);
     115             : static bool is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK);
     116             : static bool convert_saop_to_hashed_saop_walker(Node *node, void *context);
     117             : static Node *eval_const_expressions_mutator(Node *node,
     118             :                                             eval_const_expressions_context *context);
     119             : static bool contain_non_const_walker(Node *node, void *context);
     120             : static bool ece_function_is_safe(Oid funcid,
     121             :                                  eval_const_expressions_context *context);
     122             : static List *simplify_or_arguments(List *args,
     123             :                                    eval_const_expressions_context *context,
     124             :                                    bool *haveNull, bool *forceTrue);
     125             : static List *simplify_and_arguments(List *args,
     126             :                                     eval_const_expressions_context *context,
     127             :                                     bool *haveNull, bool *forceFalse);
     128             : static Node *simplify_boolean_equality(Oid opno, List *args);
     129             : static Expr *simplify_function(Oid funcid,
     130             :                                Oid result_type, int32 result_typmod,
     131             :                                Oid result_collid, Oid input_collid, List **args_p,
     132             :                                bool funcvariadic, bool process_args, bool allow_non_const,
     133             :                                eval_const_expressions_context *context);
     134             : static List *reorder_function_arguments(List *args, int pronargs,
     135             :                                         HeapTuple func_tuple);
     136             : static List *add_function_defaults(List *args, int pronargs,
     137             :                                    HeapTuple func_tuple);
     138             : static List *fetch_function_defaults(HeapTuple func_tuple);
     139             : static void recheck_cast_function_args(List *args, Oid result_type,
     140             :                                        Oid *proargtypes, int pronargs,
     141             :                                        HeapTuple func_tuple);
     142             : static Expr *evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
     143             :                                Oid result_collid, Oid input_collid, List *args,
     144             :                                bool funcvariadic,
     145             :                                HeapTuple func_tuple,
     146             :                                eval_const_expressions_context *context);
     147             : static Expr *inline_function(Oid funcid, Oid result_type, Oid result_collid,
     148             :                              Oid input_collid, List *args,
     149             :                              bool funcvariadic,
     150             :                              HeapTuple func_tuple,
     151             :                              eval_const_expressions_context *context);
     152             : static Node *substitute_actual_parameters(Node *expr, int nargs, List *args,
     153             :                                           int *usecounts);
     154             : static Node *substitute_actual_parameters_mutator(Node *node,
     155             :                                                   substitute_actual_parameters_context *context);
     156             : static void sql_inline_error_callback(void *arg);
     157             : static Query *substitute_actual_srf_parameters(Query *expr,
     158             :                                                int nargs, List *args);
     159             : static Node *substitute_actual_srf_parameters_mutator(Node *node,
     160             :                                                       substitute_actual_srf_parameters_context *context);
     161             : static bool pull_paramids_walker(Node *node, Bitmapset **context);
     162             : 
     163             : 
     164             : /*****************************************************************************
     165             :  *      Aggregate-function clause manipulation
     166             :  *****************************************************************************/
     167             : 
     168             : /*
     169             :  * contain_agg_clause
     170             :  *    Recursively search for Aggref/GroupingFunc nodes within a clause.
     171             :  *
     172             :  *    Returns true if any aggregate found.
     173             :  *
     174             :  * This does not descend into subqueries, and so should be used only after
     175             :  * reduction of sublinks to subplans, or in contexts where it's known there
     176             :  * are no subqueries.  There mustn't be outer-aggregate references either.
     177             :  *
     178             :  * (If you want something like this but able to deal with subqueries,
     179             :  * see rewriteManip.c's contain_aggs_of_level().)
     180             :  */
     181             : bool
     182        9928 : contain_agg_clause(Node *clause)
     183             : {
     184        9928 :     return contain_agg_clause_walker(clause, NULL);
     185             : }
     186             : 
     187             : static bool
     188       11944 : contain_agg_clause_walker(Node *node, void *context)
     189             : {
     190       11944 :     if (node == NULL)
     191          30 :         return false;
     192       11914 :     if (IsA(node, Aggref))
     193             :     {
     194             :         Assert(((Aggref *) node)->agglevelsup == 0);
     195        1000 :         return true;            /* abort the tree traversal and return true */
     196             :     }
     197       10914 :     if (IsA(node, GroupingFunc))
     198             :     {
     199             :         Assert(((GroupingFunc *) node)->agglevelsup == 0);
     200          30 :         return true;            /* abort the tree traversal and return true */
     201             :     }
     202             :     Assert(!IsA(node, SubLink));
     203       10884 :     return expression_tree_walker(node, contain_agg_clause_walker, context);
     204             : }
     205             : 
     206             : /*****************************************************************************
     207             :  *      Window-function clause manipulation
     208             :  *****************************************************************************/
     209             : 
     210             : /*
     211             :  * contain_window_function
     212             :  *    Recursively search for WindowFunc nodes within a clause.
     213             :  *
     214             :  * Since window functions don't have level fields, but are hard-wired to
     215             :  * be associated with the current query level, this is just the same as
     216             :  * rewriteManip.c's function.
     217             :  */
     218             : bool
     219        8556 : contain_window_function(Node *clause)
     220             : {
     221        8556 :     return contain_windowfuncs(clause);
     222             : }
     223             : 
     224             : /*
     225             :  * find_window_functions
     226             :  *    Locate all the WindowFunc nodes in an expression tree, and organize
     227             :  *    them by winref ID number.
     228             :  *
     229             :  * Caller must provide an upper bound on the winref IDs expected in the tree.
     230             :  */
     231             : WindowFuncLists *
     232        2390 : find_window_functions(Node *clause, Index maxWinRef)
     233             : {
     234        2390 :     WindowFuncLists *lists = palloc(sizeof(WindowFuncLists));
     235             : 
     236        2390 :     lists->numWindowFuncs = 0;
     237        2390 :     lists->maxWinRef = maxWinRef;
     238        2390 :     lists->windowFuncs = (List **) palloc0((maxWinRef + 1) * sizeof(List *));
     239        2390 :     (void) find_window_functions_walker(clause, lists);
     240        2390 :     return lists;
     241             : }
     242             : 
     243             : static bool
     244       20806 : find_window_functions_walker(Node *node, WindowFuncLists *lists)
     245             : {
     246       20806 :     if (node == NULL)
     247         218 :         return false;
     248       20588 :     if (IsA(node, WindowFunc))
     249             :     {
     250        3266 :         WindowFunc *wfunc = (WindowFunc *) node;
     251             : 
     252             :         /* winref is unsigned, so one-sided test is OK */
     253        3266 :         if (wfunc->winref > lists->maxWinRef)
     254           0 :             elog(ERROR, "WindowFunc contains out-of-range winref %u",
     255             :                  wfunc->winref);
     256             :         /* eliminate duplicates, so that we avoid repeated computation */
     257        3266 :         if (!list_member(lists->windowFuncs[wfunc->winref], wfunc))
     258             :         {
     259        6508 :             lists->windowFuncs[wfunc->winref] =
     260        3254 :                 lappend(lists->windowFuncs[wfunc->winref], wfunc);
     261        3254 :             lists->numWindowFuncs++;
     262             :         }
     263             : 
     264             :         /*
     265             :          * We assume that the parser checked that there are no window
     266             :          * functions in the arguments or filter clause.  Hence, we need not
     267             :          * recurse into them.  (If either the parser or the planner screws up
     268             :          * on this point, the executor will still catch it; see ExecInitExpr.)
     269             :          */
     270        3266 :         return false;
     271             :     }
     272             :     Assert(!IsA(node, SubLink));
     273       17322 :     return expression_tree_walker(node, find_window_functions_walker, lists);
     274             : }
     275             : 
     276             : 
     277             : /*****************************************************************************
     278             :  *      Support for expressions returning sets
     279             :  *****************************************************************************/
     280             : 
     281             : /*
     282             :  * expression_returns_set_rows
     283             :  *    Estimate the number of rows returned by a set-returning expression.
     284             :  *    The result is 1 if it's not a set-returning expression.
     285             :  *
     286             :  * We should only examine the top-level function or operator; it used to be
     287             :  * appropriate to recurse, but not anymore.  (Even if there are more SRFs in
     288             :  * the function's inputs, their multipliers are accounted for separately.)
     289             :  *
     290             :  * Note: keep this in sync with expression_returns_set() in nodes/nodeFuncs.c.
     291             :  */
     292             : double
     293      435608 : expression_returns_set_rows(PlannerInfo *root, Node *clause)
     294             : {
     295      435608 :     if (clause == NULL)
     296           0 :         return 1.0;
     297      435608 :     if (IsA(clause, FuncExpr))
     298             :     {
     299       64486 :         FuncExpr   *expr = (FuncExpr *) clause;
     300             : 
     301       64486 :         if (expr->funcretset)
     302       55450 :             return clamp_row_est(get_function_rows(root, expr->funcid, clause));
     303             :     }
     304      380158 :     if (IsA(clause, OpExpr))
     305             :     {
     306        3738 :         OpExpr     *expr = (OpExpr *) clause;
     307             : 
     308        3738 :         if (expr->opretset)
     309             :         {
     310           6 :             set_opfuncid(expr);
     311           6 :             return clamp_row_est(get_function_rows(root, expr->opfuncid, clause));
     312             :         }
     313             :     }
     314      380152 :     return 1.0;
     315             : }
     316             : 
     317             : 
     318             : /*****************************************************************************
     319             :  *      Subplan clause manipulation
     320             :  *****************************************************************************/
     321             : 
     322             : /*
     323             :  * contain_subplans
     324             :  *    Recursively search for subplan nodes within a clause.
     325             :  *
     326             :  * If we see a SubLink node, we will return true.  This is only possible if
     327             :  * the expression tree hasn't yet been transformed by subselect.c.  We do not
     328             :  * know whether the node will produce a true subplan or just an initplan,
     329             :  * but we make the conservative assumption that it will be a subplan.
     330             :  *
     331             :  * Returns true if any subplan found.
     332             :  */
     333             : bool
     334       48758 : contain_subplans(Node *clause)
     335             : {
     336       48758 :     return contain_subplans_walker(clause, NULL);
     337             : }
     338             : 
     339             : static bool
     340      179192 : contain_subplans_walker(Node *node, void *context)
     341             : {
     342      179192 :     if (node == NULL)
     343        7372 :         return false;
     344      171820 :     if (IsA(node, SubPlan) ||
     345      171718 :         IsA(node, AlternativeSubPlan) ||
     346      171718 :         IsA(node, SubLink))
     347         356 :         return true;            /* abort the tree traversal and return true */
     348      171464 :     return expression_tree_walker(node, contain_subplans_walker, context);
     349             : }
     350             : 
     351             : 
     352             : /*****************************************************************************
     353             :  *      Check clauses for mutable functions
     354             :  *****************************************************************************/
     355             : 
     356             : /*
     357             :  * contain_mutable_functions
     358             :  *    Recursively search for mutable functions within a clause.
     359             :  *
     360             :  * Returns true if any mutable function (or operator implemented by a
     361             :  * mutable function) is found.  This test is needed so that we don't
     362             :  * mistakenly think that something like "WHERE random() < 0.5" can be treated
     363             :  * as a constant qualification.
     364             :  *
     365             :  * This will give the right answer only for clauses that have been put
     366             :  * through expression preprocessing.  Callers outside the planner typically
     367             :  * should use contain_mutable_functions_after_planning() instead, for the
     368             :  * reasons given there.
     369             :  *
     370             :  * We will recursively look into Query nodes (i.e., SubLink sub-selects)
     371             :  * but not into SubPlans.  See comments for contain_volatile_functions().
     372             :  */
     373             : bool
     374      166500 : contain_mutable_functions(Node *clause)
     375             : {
     376      166500 :     return contain_mutable_functions_walker(clause, NULL);
     377             : }
     378             : 
     379             : static bool
     380      120996 : contain_mutable_functions_checker(Oid func_id, void *context)
     381             : {
     382      120996 :     return (func_volatile(func_id) != PROVOLATILE_IMMUTABLE);
     383             : }
     384             : 
     385             : static bool
     386      436684 : contain_mutable_functions_walker(Node *node, void *context)
     387             : {
     388      436684 :     if (node == NULL)
     389        2226 :         return false;
     390             :     /* Check for mutable functions in node itself */
     391      434458 :     if (check_functions_in_node(node, contain_mutable_functions_checker,
     392             :                                 context))
     393        6744 :         return true;
     394             : 
     395      427714 :     if (IsA(node, JsonConstructorExpr))
     396             :     {
     397           0 :         const JsonConstructorExpr *ctor = (JsonConstructorExpr *) node;
     398             :         ListCell   *lc;
     399             :         bool        is_jsonb;
     400             : 
     401           0 :         is_jsonb = ctor->returning->format->format_type == JS_FORMAT_JSONB;
     402             : 
     403             :         /*
     404             :          * Check argument_type => json[b] conversions specifically.  We still
     405             :          * recurse to check 'args' below, but here we want to specifically
     406             :          * check whether or not the emitted clause would fail to be immutable
     407             :          * because of TimeZone, for example.
     408             :          */
     409           0 :         foreach(lc, ctor->args)
     410             :         {
     411           0 :             Oid         typid = exprType(lfirst(lc));
     412             : 
     413           0 :             if (is_jsonb ?
     414           0 :                 !to_jsonb_is_immutable(typid) :
     415           0 :                 !to_json_is_immutable(typid))
     416           0 :                 return true;
     417             :         }
     418             : 
     419             :         /* Check all subnodes */
     420             :     }
     421             : 
     422      427714 :     if (IsA(node, JsonExpr))
     423             :     {
     424         234 :         JsonExpr   *jexpr = castNode(JsonExpr, node);
     425             :         Const      *cnst;
     426             : 
     427         234 :         if (!IsA(jexpr->path_spec, Const))
     428           0 :             return true;
     429             : 
     430         234 :         cnst = castNode(Const, jexpr->path_spec);
     431             : 
     432             :         Assert(cnst->consttype == JSONPATHOID);
     433         234 :         if (cnst->constisnull)
     434           0 :             return false;
     435             : 
     436         234 :         if (jspIsMutable(DatumGetJsonPathP(cnst->constvalue),
     437             :                          jexpr->passing_names, jexpr->passing_values))
     438         162 :             return true;
     439             :     }
     440             : 
     441      427552 :     if (IsA(node, SQLValueFunction))
     442             :     {
     443             :         /* all variants of SQLValueFunction are stable */
     444         412 :         return true;
     445             :     }
     446             : 
     447      427140 :     if (IsA(node, NextValueExpr))
     448             :     {
     449             :         /* NextValueExpr is volatile */
     450           0 :         return true;
     451             :     }
     452             : 
     453             :     /*
     454             :      * It should be safe to treat MinMaxExpr as immutable, because it will
     455             :      * depend on a non-cross-type btree comparison function, and those should
     456             :      * always be immutable.  Treating XmlExpr as immutable is more dubious,
     457             :      * and treating CoerceToDomain as immutable is outright dangerous.  But we
     458             :      * have done so historically, and changing this would probably cause more
     459             :      * problems than it would fix.  In practice, if you have a non-immutable
     460             :      * domain constraint you are in for pain anyhow.
     461             :      */
     462             : 
     463             :     /* Recurse to check arguments */
     464      427140 :     if (IsA(node, Query))
     465             :     {
     466             :         /* Recurse into subselects */
     467           0 :         return query_tree_walker((Query *) node,
     468             :                                  contain_mutable_functions_walker,
     469             :                                  context, 0);
     470             :     }
     471      427140 :     return expression_tree_walker(node, contain_mutable_functions_walker,
     472             :                                   context);
     473             : }
     474             : 
     475             : /*
     476             :  * contain_mutable_functions_after_planning
     477             :  *    Test whether given expression contains mutable functions.
     478             :  *
     479             :  * This is a wrapper for contain_mutable_functions() that is safe to use from
     480             :  * outside the planner.  The difference is that it first runs the expression
     481             :  * through expression_planner().  There are two key reasons why we need that:
     482             :  *
     483             :  * First, function default arguments will get inserted, which may affect
     484             :  * volatility (consider "default now()").
     485             :  *
     486             :  * Second, inline-able functions will get inlined, which may allow us to
     487             :  * conclude that the function is really less volatile than it's marked.
     488             :  * As an example, polymorphic functions must be marked with the most volatile
     489             :  * behavior that they have for any input type, but once we inline the
     490             :  * function we may be able to conclude that it's not so volatile for the
     491             :  * particular input type we're dealing with.
     492             :  */
     493             : bool
     494        3202 : contain_mutable_functions_after_planning(Expr *expr)
     495             : {
     496             :     /* We assume here that expression_planner() won't scribble on its input */
     497        3202 :     expr = expression_planner(expr);
     498             : 
     499             :     /* Now we can search for non-immutable functions */
     500        3202 :     return contain_mutable_functions((Node *) expr);
     501             : }
     502             : 
     503             : 
     504             : /*****************************************************************************
     505             :  *      Check clauses for volatile functions
     506             :  *****************************************************************************/
     507             : 
     508             : /*
     509             :  * contain_volatile_functions
     510             :  *    Recursively search for volatile functions within a clause.
     511             :  *
     512             :  * Returns true if any volatile function (or operator implemented by a
     513             :  * volatile function) is found. This test prevents, for example,
     514             :  * invalid conversions of volatile expressions into indexscan quals.
     515             :  *
     516             :  * This will give the right answer only for clauses that have been put
     517             :  * through expression preprocessing.  Callers outside the planner typically
     518             :  * should use contain_volatile_functions_after_planning() instead, for the
     519             :  * reasons given there.
     520             :  *
     521             :  * We will recursively look into Query nodes (i.e., SubLink sub-selects)
     522             :  * but not into SubPlans.  This is a bit odd, but intentional.  If we are
     523             :  * looking at a SubLink, we are probably deciding whether a query tree
     524             :  * transformation is safe, and a contained sub-select should affect that;
     525             :  * for example, duplicating a sub-select containing a volatile function
     526             :  * would be bad.  However, once we've got to the stage of having SubPlans,
     527             :  * subsequent planning need not consider volatility within those, since
     528             :  * the executor won't change its evaluation rules for a SubPlan based on
     529             :  * volatility.
     530             :  *
     531             :  * For some node types, for example, RestrictInfo and PathTarget, we cache
     532             :  * whether we found any volatile functions or not and reuse that value in any
     533             :  * future checks for that node.  All of the logic for determining if the
     534             :  * cached value should be set to VOLATILITY_NOVOLATILE or VOLATILITY_VOLATILE
     535             :  * belongs in this function.  Any code which makes changes to these nodes
     536             :  * which could change the outcome this function must set the cached value back
     537             :  * to VOLATILITY_UNKNOWN.  That allows this function to redetermine the
     538             :  * correct value during the next call, should we need to redetermine if the
     539             :  * node contains any volatile functions again in the future.
     540             :  */
     541             : bool
     542     3364954 : contain_volatile_functions(Node *clause)
     543             : {
     544     3364954 :     return contain_volatile_functions_walker(clause, NULL);
     545             : }
     546             : 
     547             : static bool
     548      909998 : contain_volatile_functions_checker(Oid func_id, void *context)
     549             : {
     550      909998 :     return (func_volatile(func_id) == PROVOLATILE_VOLATILE);
     551             : }
     552             : 
     553             : static bool
     554     7649560 : contain_volatile_functions_walker(Node *node, void *context)
     555             : {
     556     7649560 :     if (node == NULL)
     557      218872 :         return false;
     558             :     /* Check for volatile functions in node itself */
     559     7430688 :     if (check_functions_in_node(node, contain_volatile_functions_checker,
     560             :                                 context))
     561        1906 :         return true;
     562             : 
     563     7428782 :     if (IsA(node, NextValueExpr))
     564             :     {
     565             :         /* NextValueExpr is volatile */
     566          42 :         return true;
     567             :     }
     568             : 
     569     7428740 :     if (IsA(node, RestrictInfo))
     570             :     {
     571     1326426 :         RestrictInfo *rinfo = (RestrictInfo *) node;
     572             : 
     573             :         /*
     574             :          * For RestrictInfo, check if we've checked the volatility of it
     575             :          * before.  If so, we can just use the cached value and not bother
     576             :          * checking it again.  Otherwise, check it and cache if whether we
     577             :          * found any volatile functions.
     578             :          */
     579     1326426 :         if (rinfo->has_volatile == VOLATILITY_NOVOLATILE)
     580      815484 :             return false;
     581      510942 :         else if (rinfo->has_volatile == VOLATILITY_VOLATILE)
     582           8 :             return true;
     583             :         else
     584             :         {
     585             :             bool        hasvolatile;
     586             : 
     587      510934 :             hasvolatile = contain_volatile_functions_walker((Node *) rinfo->clause,
     588             :                                                             context);
     589      510934 :             if (hasvolatile)
     590          64 :                 rinfo->has_volatile = VOLATILITY_VOLATILE;
     591             :             else
     592      510870 :                 rinfo->has_volatile = VOLATILITY_NOVOLATILE;
     593             : 
     594      510934 :             return hasvolatile;
     595             :         }
     596             :     }
     597             : 
     598     6102314 :     if (IsA(node, PathTarget))
     599             :     {
     600      381274 :         PathTarget *target = (PathTarget *) node;
     601             : 
     602             :         /*
     603             :          * We also do caching for PathTarget the same as we do above for
     604             :          * RestrictInfos.
     605             :          */
     606      381274 :         if (target->has_volatile_expr == VOLATILITY_NOVOLATILE)
     607      315670 :             return false;
     608       65604 :         else if (target->has_volatile_expr == VOLATILITY_VOLATILE)
     609           0 :             return true;
     610             :         else
     611             :         {
     612             :             bool        hasvolatile;
     613             : 
     614       65604 :             hasvolatile = contain_volatile_functions_walker((Node *) target->exprs,
     615             :                                                             context);
     616             : 
     617       65604 :             if (hasvolatile)
     618           0 :                 target->has_volatile_expr = VOLATILITY_VOLATILE;
     619             :             else
     620       65604 :                 target->has_volatile_expr = VOLATILITY_NOVOLATILE;
     621             : 
     622       65604 :             return hasvolatile;
     623             :         }
     624             :     }
     625             : 
     626             :     /*
     627             :      * See notes in contain_mutable_functions_walker about why we treat
     628             :      * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
     629             :      * SQLValueFunction is stable.  Hence, none of them are of interest here.
     630             :      */
     631             : 
     632             :     /* Recurse to check arguments */
     633     5721040 :     if (IsA(node, Query))
     634             :     {
     635             :         /* Recurse into subselects */
     636        7062 :         return query_tree_walker((Query *) node,
     637             :                                  contain_volatile_functions_walker,
     638             :                                  context, 0);
     639             :     }
     640     5713978 :     return expression_tree_walker(node, contain_volatile_functions_walker,
     641             :                                   context);
     642             : }
     643             : 
     644             : /*
     645             :  * contain_volatile_functions_after_planning
     646             :  *    Test whether given expression contains volatile functions.
     647             :  *
     648             :  * This is a wrapper for contain_volatile_functions() that is safe to use from
     649             :  * outside the planner.  The difference is that it first runs the expression
     650             :  * through expression_planner().  There are two key reasons why we need that:
     651             :  *
     652             :  * First, function default arguments will get inserted, which may affect
     653             :  * volatility (consider "default random()").
     654             :  *
     655             :  * Second, inline-able functions will get inlined, which may allow us to
     656             :  * conclude that the function is really less volatile than it's marked.
     657             :  * As an example, polymorphic functions must be marked with the most volatile
     658             :  * behavior that they have for any input type, but once we inline the
     659             :  * function we may be able to conclude that it's not so volatile for the
     660             :  * particular input type we're dealing with.
     661             :  */
     662             : bool
     663           0 : contain_volatile_functions_after_planning(Expr *expr)
     664             : {
     665             :     /* We assume here that expression_planner() won't scribble on its input */
     666           0 :     expr = expression_planner(expr);
     667             : 
     668             :     /* Now we can search for volatile functions */
     669           0 :     return contain_volatile_functions((Node *) expr);
     670             : }
     671             : 
     672             : /*
     673             :  * Special purpose version of contain_volatile_functions() for use in COPY:
     674             :  * ignore nextval(), but treat all other functions normally.
     675             :  */
     676             : bool
     677         252 : contain_volatile_functions_not_nextval(Node *clause)
     678             : {
     679         252 :     return contain_volatile_functions_not_nextval_walker(clause, NULL);
     680             : }
     681             : 
     682             : static bool
     683          64 : contain_volatile_functions_not_nextval_checker(Oid func_id, void *context)
     684             : {
     685         104 :     return (func_id != F_NEXTVAL &&
     686          40 :             func_volatile(func_id) == PROVOLATILE_VOLATILE);
     687             : }
     688             : 
     689             : static bool
     690         312 : contain_volatile_functions_not_nextval_walker(Node *node, void *context)
     691             : {
     692         312 :     if (node == NULL)
     693           0 :         return false;
     694             :     /* Check for volatile functions in node itself */
     695         312 :     if (check_functions_in_node(node,
     696             :                                 contain_volatile_functions_not_nextval_checker,
     697             :                                 context))
     698           6 :         return true;
     699             : 
     700             :     /*
     701             :      * See notes in contain_mutable_functions_walker about why we treat
     702             :      * MinMaxExpr, XmlExpr, and CoerceToDomain as immutable, while
     703             :      * SQLValueFunction is stable.  Hence, none of them are of interest here.
     704             :      * Also, since we're intentionally ignoring nextval(), presumably we
     705             :      * should ignore NextValueExpr.
     706             :      */
     707             : 
     708             :     /* Recurse to check arguments */
     709         306 :     if (IsA(node, Query))
     710             :     {
     711             :         /* Recurse into subselects */
     712           0 :         return query_tree_walker((Query *) node,
     713             :                                  contain_volatile_functions_not_nextval_walker,
     714             :                                  context, 0);
     715             :     }
     716         306 :     return expression_tree_walker(node,
     717             :                                   contain_volatile_functions_not_nextval_walker,
     718             :                                   context);
     719             : }
     720             : 
     721             : 
     722             : /*****************************************************************************
     723             :  *      Check queries for parallel unsafe and/or restricted constructs
     724             :  *****************************************************************************/
     725             : 
     726             : /*
     727             :  * max_parallel_hazard
     728             :  *      Find the worst parallel-hazard level in the given query
     729             :  *
     730             :  * Returns the worst function hazard property (the earliest in this list:
     731             :  * PROPARALLEL_UNSAFE, PROPARALLEL_RESTRICTED, PROPARALLEL_SAFE) that can
     732             :  * be found in the given parsetree.  We use this to find out whether the query
     733             :  * can be parallelized at all.  The caller will also save the result in
     734             :  * PlannerGlobal so as to short-circuit checks of portions of the querytree
     735             :  * later, in the common case where everything is SAFE.
     736             :  */
     737             : char
     738      338752 : max_parallel_hazard(Query *parse)
     739             : {
     740             :     max_parallel_hazard_context context;
     741             : 
     742      338752 :     context.max_hazard = PROPARALLEL_SAFE;
     743      338752 :     context.max_interesting = PROPARALLEL_UNSAFE;
     744      338752 :     context.safe_param_ids = NIL;
     745      338752 :     (void) max_parallel_hazard_walker((Node *) parse, &context);
     746      338752 :     return context.max_hazard;
     747             : }
     748             : 
     749             : /*
     750             :  * is_parallel_safe
     751             :  *      Detect whether the given expr contains only parallel-safe functions
     752             :  *
     753             :  * root->glob->maxParallelHazard must previously have been set to the
     754             :  * result of max_parallel_hazard() on the whole query.
     755             :  */
     756             : bool
     757     2349242 : is_parallel_safe(PlannerInfo *root, Node *node)
     758             : {
     759             :     max_parallel_hazard_context context;
     760             :     PlannerInfo *proot;
     761             :     ListCell   *l;
     762             : 
     763             :     /*
     764             :      * Even if the original querytree contained nothing unsafe, we need to
     765             :      * search the expression if we have generated any PARAM_EXEC Params while
     766             :      * planning, because those are parallel-restricted and there might be one
     767             :      * in this expression.  But otherwise we don't need to look.
     768             :      */
     769     2349242 :     if (root->glob->maxParallelHazard == PROPARALLEL_SAFE &&
     770     1402776 :         root->glob->paramExecTypes == NIL)
     771     1370440 :         return true;
     772             :     /* Else use max_parallel_hazard's search logic, but stop on RESTRICTED */
     773      978802 :     context.max_hazard = PROPARALLEL_SAFE;
     774      978802 :     context.max_interesting = PROPARALLEL_RESTRICTED;
     775      978802 :     context.safe_param_ids = NIL;
     776             : 
     777             :     /*
     778             :      * The params that refer to the same or parent query level are considered
     779             :      * parallel-safe.  The idea is that we compute such params at Gather or
     780             :      * Gather Merge node and pass their value to workers.
     781             :      */
     782     2348422 :     for (proot = root; proot != NULL; proot = proot->parent_root)
     783             :     {
     784     1444788 :         foreach(l, proot->init_plans)
     785             :         {
     786       75168 :             SubPlan    *initsubplan = (SubPlan *) lfirst(l);
     787             : 
     788       75168 :             context.safe_param_ids = list_concat(context.safe_param_ids,
     789       75168 :                                                  initsubplan->setParam);
     790             :         }
     791             :     }
     792             : 
     793      978802 :     return !max_parallel_hazard_walker(node, &context);
     794             : }
     795             : 
     796             : /* core logic for all parallel-hazard checks */
     797             : static bool
     798     1593048 : max_parallel_hazard_test(char proparallel, max_parallel_hazard_context *context)
     799             : {
     800     1593048 :     switch (proparallel)
     801             :     {
     802     1311440 :         case PROPARALLEL_SAFE:
     803             :             /* nothing to see here, move along */
     804     1311440 :             break;
     805      204520 :         case PROPARALLEL_RESTRICTED:
     806             :             /* increase max_hazard to RESTRICTED */
     807             :             Assert(context->max_hazard != PROPARALLEL_UNSAFE);
     808      204520 :             context->max_hazard = proparallel;
     809             :             /* done if we are not expecting any unsafe functions */
     810      204520 :             if (context->max_interesting == proparallel)
     811      105306 :                 return true;
     812       99214 :             break;
     813       77088 :         case PROPARALLEL_UNSAFE:
     814       77088 :             context->max_hazard = proparallel;
     815             :             /* we're always done at the first unsafe construct */
     816       77088 :             return true;
     817           0 :         default:
     818           0 :             elog(ERROR, "unrecognized proparallel value \"%c\"", proparallel);
     819             :             break;
     820             :     }
     821     1410654 :     return false;
     822             : }
     823             : 
     824             : /* check_functions_in_node callback */
     825             : static bool
     826     1455158 : max_parallel_hazard_checker(Oid func_id, void *context)
     827             : {
     828     1455158 :     return max_parallel_hazard_test(func_parallel(func_id),
     829             :                                     (max_parallel_hazard_context *) context);
     830             : }
     831             : 
     832             : static bool
     833    20701044 : max_parallel_hazard_walker(Node *node, max_parallel_hazard_context *context)
     834             : {
     835    20701044 :     if (node == NULL)
     836     5531218 :         return false;
     837             : 
     838             :     /* Check for hazardous functions in node itself */
     839    15169826 :     if (check_functions_in_node(node, max_parallel_hazard_checker,
     840             :                                 context))
     841      105924 :         return true;
     842             : 
     843             :     /*
     844             :      * It should be OK to treat MinMaxExpr as parallel-safe, since btree
     845             :      * opclass support functions are generally parallel-safe.  XmlExpr is a
     846             :      * bit more dubious but we can probably get away with it.  We err on the
     847             :      * side of caution by treating CoerceToDomain as parallel-restricted.
     848             :      * (Note: in principle that's wrong because a domain constraint could
     849             :      * contain a parallel-unsafe function; but useful constraints probably
     850             :      * never would have such, and assuming they do would cripple use of
     851             :      * parallel query in the presence of domain types.)  SQLValueFunction
     852             :      * should be safe in all cases.  NextValueExpr is parallel-unsafe.
     853             :      */
     854    15063902 :     if (IsA(node, CoerceToDomain))
     855             :     {
     856       19530 :         if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
     857        6310 :             return true;
     858             :     }
     859             : 
     860    15044372 :     else if (IsA(node, NextValueExpr))
     861             :     {
     862         348 :         if (max_parallel_hazard_test(PROPARALLEL_UNSAFE, context))
     863         348 :             return true;
     864             :     }
     865             : 
     866             :     /*
     867             :      * Treat window functions as parallel-restricted because we aren't sure
     868             :      * whether the input row ordering is fully deterministic, and the output
     869             :      * of window functions might vary across workers if not.  (In some cases,
     870             :      * like where the window frame orders by a primary key, we could relax
     871             :      * this restriction.  But it doesn't currently seem worth expending extra
     872             :      * effort to do so.)
     873             :      */
     874    15044024 :     else if (IsA(node, WindowFunc))
     875             :     {
     876        5544 :         if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
     877        2462 :             return true;
     878             :     }
     879             : 
     880             :     /*
     881             :      * As a notational convenience for callers, look through RestrictInfo.
     882             :      */
     883    15038480 :     else if (IsA(node, RestrictInfo))
     884             :     {
     885      248966 :         RestrictInfo *rinfo = (RestrictInfo *) node;
     886             : 
     887      248966 :         return max_parallel_hazard_walker((Node *) rinfo->clause, context);
     888             :     }
     889             : 
     890             :     /*
     891             :      * Really we should not see SubLink during a max_interesting == restricted
     892             :      * scan, but if we do, return true.
     893             :      */
     894    14789514 :     else if (IsA(node, SubLink))
     895             :     {
     896       40286 :         if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
     897           0 :             return true;
     898             :     }
     899             : 
     900             :     /*
     901             :      * Only parallel-safe SubPlans can be sent to workers.  Within the
     902             :      * testexpr of the SubPlan, Params representing the output columns of the
     903             :      * subplan can be treated as parallel-safe, so temporarily add their IDs
     904             :      * to the safe_param_ids list while examining the testexpr.
     905             :      */
     906    14749228 :     else if (IsA(node, SubPlan))
     907             :     {
     908       31074 :         SubPlan    *subplan = (SubPlan *) node;
     909             :         List       *save_safe_param_ids;
     910             : 
     911       61818 :         if (!subplan->parallel_safe &&
     912       30744 :             max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
     913       30744 :             return true;
     914         330 :         save_safe_param_ids = context->safe_param_ids;
     915         660 :         context->safe_param_ids = list_concat_copy(context->safe_param_ids,
     916         330 :                                                    subplan->paramIds);
     917         330 :         if (max_parallel_hazard_walker(subplan->testexpr, context))
     918           6 :             return true;        /* no need to restore safe_param_ids */
     919         324 :         list_free(context->safe_param_ids);
     920         324 :         context->safe_param_ids = save_safe_param_ids;
     921             :         /* we must also check args, but no special Param treatment there */
     922         324 :         if (max_parallel_hazard_walker((Node *) subplan->args, context))
     923           0 :             return true;
     924             :         /* don't want to recurse normally, so we're done */
     925         324 :         return false;
     926             :     }
     927             : 
     928             :     /*
     929             :      * We can't pass Params to workers at the moment either, so they are also
     930             :      * parallel-restricted, unless they are PARAM_EXTERN Params or are
     931             :      * PARAM_EXEC Params listed in safe_param_ids, meaning they could be
     932             :      * either generated within workers or can be computed by the leader and
     933             :      * then their value can be passed to workers.
     934             :      */
     935    14718154 :     else if (IsA(node, Param))
     936             :     {
     937      108900 :         Param      *param = (Param *) node;
     938             : 
     939      108900 :         if (param->paramkind == PARAM_EXTERN)
     940       56894 :             return false;
     941             : 
     942       52006 :         if (param->paramkind != PARAM_EXEC ||
     943       47108 :             !list_member_int(context->safe_param_ids, param->paramid))
     944             :         {
     945       41438 :             if (max_parallel_hazard_test(PROPARALLEL_RESTRICTED, context))
     946       36606 :                 return true;
     947             :         }
     948       15400 :         return false;           /* nothing to recurse to */
     949             :     }
     950             : 
     951             :     /*
     952             :      * When we're first invoked on a completely unplanned tree, we must
     953             :      * recurse into subqueries so to as to locate parallel-unsafe constructs
     954             :      * anywhere in the tree.
     955             :      */
     956    14609254 :     else if (IsA(node, Query))
     957             :     {
     958      437014 :         Query      *query = (Query *) node;
     959             : 
     960             :         /* SELECT FOR UPDATE/SHARE must be treated as unsafe */
     961      437014 :         if (query->rowMarks != NULL)
     962             :         {
     963        1804 :             context->max_hazard = PROPARALLEL_UNSAFE;
     964        1804 :             return true;
     965             :         }
     966             : 
     967             :         /* Recurse into subselects */
     968      435210 :         return query_tree_walker(query,
     969             :                                  max_parallel_hazard_walker,
     970             :                                  context, 0);
     971             :     }
     972             : 
     973             :     /* Recurse to check arguments */
     974    14228828 :     return expression_tree_walker(node,
     975             :                                   max_parallel_hazard_walker,
     976             :                                   context);
     977             : }
     978             : 
     979             : 
     980             : /*****************************************************************************
     981             :  *      Check clauses for nonstrict functions
     982             :  *****************************************************************************/
     983             : 
     984             : /*
     985             :  * contain_nonstrict_functions
     986             :  *    Recursively search for nonstrict functions within a clause.
     987             :  *
     988             :  * Returns true if any nonstrict construct is found --- ie, anything that
     989             :  * could produce non-NULL output with a NULL input.
     990             :  *
     991             :  * The idea here is that the caller has verified that the expression contains
     992             :  * one or more Var or Param nodes (as appropriate for the caller's need), and
     993             :  * now wishes to prove that the expression result will be NULL if any of these
     994             :  * inputs is NULL.  If we return false, then the proof succeeded.
     995             :  */
     996             : bool
     997        2370 : contain_nonstrict_functions(Node *clause)
     998             : {
     999        2370 :     return contain_nonstrict_functions_walker(clause, NULL);
    1000             : }
    1001             : 
    1002             : static bool
    1003        2462 : contain_nonstrict_functions_checker(Oid func_id, void *context)
    1004             : {
    1005        2462 :     return !func_strict(func_id);
    1006             : }
    1007             : 
    1008             : static bool
    1009        8286 : contain_nonstrict_functions_walker(Node *node, void *context)
    1010             : {
    1011        8286 :     if (node == NULL)
    1012           0 :         return false;
    1013        8286 :     if (IsA(node, Aggref))
    1014             :     {
    1015             :         /* an aggregate could return non-null with null input */
    1016           0 :         return true;
    1017             :     }
    1018        8286 :     if (IsA(node, GroupingFunc))
    1019             :     {
    1020             :         /*
    1021             :          * A GroupingFunc doesn't evaluate its arguments, and therefore must
    1022             :          * be treated as nonstrict.
    1023             :          */
    1024           0 :         return true;
    1025             :     }
    1026        8286 :     if (IsA(node, WindowFunc))
    1027             :     {
    1028             :         /* a window function could return non-null with null input */
    1029           0 :         return true;
    1030             :     }
    1031        8286 :     if (IsA(node, SubscriptingRef))
    1032             :     {
    1033           0 :         SubscriptingRef *sbsref = (SubscriptingRef *) node;
    1034             :         const SubscriptRoutines *sbsroutines;
    1035             : 
    1036             :         /* Subscripting assignment is always presumed nonstrict */
    1037           0 :         if (sbsref->refassgnexpr != NULL)
    1038           0 :             return true;
    1039             :         /* Otherwise we must look up the subscripting support methods */
    1040           0 :         sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype, NULL);
    1041           0 :         if (!(sbsroutines && sbsroutines->fetch_strict))
    1042           0 :             return true;
    1043             :         /* else fall through to check args */
    1044             :     }
    1045        8286 :     if (IsA(node, DistinctExpr))
    1046             :     {
    1047             :         /* IS DISTINCT FROM is inherently non-strict */
    1048           0 :         return true;
    1049             :     }
    1050        8286 :     if (IsA(node, NullIfExpr))
    1051             :     {
    1052             :         /* NULLIF is inherently non-strict */
    1053           0 :         return true;
    1054             :     }
    1055        8286 :     if (IsA(node, BoolExpr))
    1056             :     {
    1057          18 :         BoolExpr   *expr = (BoolExpr *) node;
    1058             : 
    1059          18 :         switch (expr->boolop)
    1060             :         {
    1061          18 :             case AND_EXPR:
    1062             :             case OR_EXPR:
    1063             :                 /* AND, OR are inherently non-strict */
    1064          18 :                 return true;
    1065           0 :             default:
    1066           0 :                 break;
    1067             :         }
    1068             :     }
    1069        8268 :     if (IsA(node, SubLink))
    1070             :     {
    1071             :         /* In some cases a sublink might be strict, but in general not */
    1072          12 :         return true;
    1073             :     }
    1074        8256 :     if (IsA(node, SubPlan))
    1075           0 :         return true;
    1076        8256 :     if (IsA(node, AlternativeSubPlan))
    1077           0 :         return true;
    1078        8256 :     if (IsA(node, FieldStore))
    1079           0 :         return true;
    1080        8256 :     if (IsA(node, CoerceViaIO))
    1081             :     {
    1082             :         /*
    1083             :          * CoerceViaIO is strict regardless of whether the I/O functions are,
    1084             :          * so just go look at its argument; asking check_functions_in_node is
    1085             :          * useless expense and could deliver the wrong answer.
    1086             :          */
    1087        1068 :         return contain_nonstrict_functions_walker((Node *) ((CoerceViaIO *) node)->arg,
    1088             :                                                   context);
    1089             :     }
    1090        7188 :     if (IsA(node, ArrayCoerceExpr))
    1091             :     {
    1092             :         /*
    1093             :          * ArrayCoerceExpr is strict at the array level, regardless of what
    1094             :          * the per-element expression is; so we should ignore elemexpr and
    1095             :          * recurse only into the arg.
    1096             :          */
    1097           0 :         return contain_nonstrict_functions_walker((Node *) ((ArrayCoerceExpr *) node)->arg,
    1098             :                                                   context);
    1099             :     }
    1100        7188 :     if (IsA(node, CaseExpr))
    1101          64 :         return true;
    1102        7124 :     if (IsA(node, ArrayExpr))
    1103           0 :         return true;
    1104        7124 :     if (IsA(node, RowExpr))
    1105           4 :         return true;
    1106        7120 :     if (IsA(node, RowCompareExpr))
    1107           0 :         return true;
    1108        7120 :     if (IsA(node, CoalesceExpr))
    1109         254 :         return true;
    1110        6866 :     if (IsA(node, MinMaxExpr))
    1111          60 :         return true;
    1112        6806 :     if (IsA(node, XmlExpr))
    1113           0 :         return true;
    1114        6806 :     if (IsA(node, NullTest))
    1115          24 :         return true;
    1116        6782 :     if (IsA(node, BooleanTest))
    1117           0 :         return true;
    1118        6782 :     if (IsA(node, JsonConstructorExpr))
    1119          12 :         return true;
    1120             : 
    1121             :     /* Check other function-containing nodes */
    1122        6770 :     if (check_functions_in_node(node, contain_nonstrict_functions_checker,
    1123             :                                 context))
    1124           0 :         return true;
    1125             : 
    1126        6770 :     return expression_tree_walker(node, contain_nonstrict_functions_walker,
    1127             :                                   context);
    1128             : }
    1129             : 
    1130             : /*****************************************************************************
    1131             :  *      Check clauses for Params
    1132             :  *****************************************************************************/
    1133             : 
    1134             : /*
    1135             :  * contain_exec_param
    1136             :  *    Recursively search for PARAM_EXEC Params within a clause.
    1137             :  *
    1138             :  * Returns true if the clause contains any PARAM_EXEC Param with a paramid
    1139             :  * appearing in the given list of Param IDs.  Does not descend into
    1140             :  * subqueries!
    1141             :  */
    1142             : bool
    1143        2986 : contain_exec_param(Node *clause, List *param_ids)
    1144             : {
    1145        2986 :     return contain_exec_param_walker(clause, param_ids);
    1146             : }
    1147             : 
    1148             : static bool
    1149        3256 : contain_exec_param_walker(Node *node, List *param_ids)
    1150             : {
    1151        3256 :     if (node == NULL)
    1152          30 :         return false;
    1153        3226 :     if (IsA(node, Param))
    1154             :     {
    1155          12 :         Param      *p = (Param *) node;
    1156             : 
    1157          24 :         if (p->paramkind == PARAM_EXEC &&
    1158          12 :             list_member_int(param_ids, p->paramid))
    1159          12 :             return true;
    1160             :     }
    1161        3214 :     return expression_tree_walker(node, contain_exec_param_walker, param_ids);
    1162             : }
    1163             : 
    1164             : /*****************************************************************************
    1165             :  *      Check clauses for context-dependent nodes
    1166             :  *****************************************************************************/
    1167             : 
    1168             : /*
    1169             :  * contain_context_dependent_node
    1170             :  *    Recursively search for context-dependent nodes within a clause.
    1171             :  *
    1172             :  * CaseTestExpr nodes must appear directly within the corresponding CaseExpr,
    1173             :  * not nested within another one, or they'll see the wrong test value.  If one
    1174             :  * appears "bare" in the arguments of a SQL function, then we can't inline the
    1175             :  * SQL function for fear of creating such a situation.  The same applies for
    1176             :  * CaseTestExpr used within the elemexpr of an ArrayCoerceExpr.
    1177             :  *
    1178             :  * CoerceToDomainValue would have the same issue if domain CHECK expressions
    1179             :  * could get inlined into larger expressions, but presently that's impossible.
    1180             :  * Still, it might be allowed in future, or other node types with similar
    1181             :  * issues might get invented.  So give this function a generic name, and set
    1182             :  * up the recursion state to allow multiple flag bits.
    1183             :  */
    1184             : static bool
    1185        3250 : contain_context_dependent_node(Node *clause)
    1186             : {
    1187        3250 :     int         flags = 0;
    1188             : 
    1189        3250 :     return contain_context_dependent_node_walker(clause, &flags);
    1190             : }
    1191             : 
    1192             : #define CCDN_CASETESTEXPR_OK    0x0001  /* CaseTestExpr okay here? */
    1193             : 
    1194             : static bool
    1195        9892 : contain_context_dependent_node_walker(Node *node, int *flags)
    1196             : {
    1197        9892 :     if (node == NULL)
    1198         194 :         return false;
    1199        9698 :     if (IsA(node, CaseTestExpr))
    1200           6 :         return !(*flags & CCDN_CASETESTEXPR_OK);
    1201        9692 :     else if (IsA(node, CaseExpr))
    1202             :     {
    1203           0 :         CaseExpr   *caseexpr = (CaseExpr *) node;
    1204             : 
    1205             :         /*
    1206             :          * If this CASE doesn't have a test expression, then it doesn't create
    1207             :          * a context in which CaseTestExprs should appear, so just fall
    1208             :          * through and treat it as a generic expression node.
    1209             :          */
    1210           0 :         if (caseexpr->arg)
    1211             :         {
    1212           0 :             int         save_flags = *flags;
    1213             :             bool        res;
    1214             : 
    1215             :             /*
    1216             :              * Note: in principle, we could distinguish the various sub-parts
    1217             :              * of a CASE construct and set the flag bit only for some of them,
    1218             :              * since we are only expecting CaseTestExprs to appear in the
    1219             :              * "expr" subtree of the CaseWhen nodes.  But it doesn't really
    1220             :              * seem worth any extra code.  If there are any bare CaseTestExprs
    1221             :              * elsewhere in the CASE, something's wrong already.
    1222             :              */
    1223           0 :             *flags |= CCDN_CASETESTEXPR_OK;
    1224           0 :             res = expression_tree_walker(node,
    1225             :                                          contain_context_dependent_node_walker,
    1226             :                                          flags);
    1227           0 :             *flags = save_flags;
    1228           0 :             return res;
    1229             :         }
    1230             :     }
    1231        9692 :     else if (IsA(node, ArrayCoerceExpr))
    1232             :     {
    1233           0 :         ArrayCoerceExpr *ac = (ArrayCoerceExpr *) node;
    1234             :         int         save_flags;
    1235             :         bool        res;
    1236             : 
    1237             :         /* Check the array expression */
    1238           0 :         if (contain_context_dependent_node_walker((Node *) ac->arg, flags))
    1239           0 :             return true;
    1240             : 
    1241             :         /* Check the elemexpr, which is allowed to contain CaseTestExpr */
    1242           0 :         save_flags = *flags;
    1243           0 :         *flags |= CCDN_CASETESTEXPR_OK;
    1244           0 :         res = contain_context_dependent_node_walker((Node *) ac->elemexpr,
    1245             :                                                     flags);
    1246           0 :         *flags = save_flags;
    1247           0 :         return res;
    1248             :     }
    1249        9692 :     return expression_tree_walker(node, contain_context_dependent_node_walker,
    1250             :                                   flags);
    1251             : }
    1252             : 
    1253             : /*****************************************************************************
    1254             :  *        Check clauses for Vars passed to non-leakproof functions
    1255             :  *****************************************************************************/
    1256             : 
    1257             : /*
    1258             :  * contain_leaked_vars
    1259             :  *      Recursively scan a clause to discover whether it contains any Var
    1260             :  *      nodes (of the current query level) that are passed as arguments to
    1261             :  *      leaky functions.
    1262             :  *
    1263             :  * Returns true if the clause contains any non-leakproof functions that are
    1264             :  * passed Var nodes of the current query level, and which might therefore leak
    1265             :  * data.  Such clauses must be applied after any lower-level security barrier
    1266             :  * clauses.
    1267             :  */
    1268             : bool
    1269        6122 : contain_leaked_vars(Node *clause)
    1270             : {
    1271        6122 :     return contain_leaked_vars_walker(clause, NULL);
    1272             : }
    1273             : 
    1274             : static bool
    1275        6094 : contain_leaked_vars_checker(Oid func_id, void *context)
    1276             : {
    1277        6094 :     return !get_func_leakproof(func_id);
    1278             : }
    1279             : 
    1280             : static bool
    1281       13012 : contain_leaked_vars_walker(Node *node, void *context)
    1282             : {
    1283       13012 :     if (node == NULL)
    1284           0 :         return false;
    1285             : 
    1286       13012 :     switch (nodeTag(node))
    1287             :     {
    1288        6846 :         case T_Var:
    1289             :         case T_Const:
    1290             :         case T_Param:
    1291             :         case T_ArrayExpr:
    1292             :         case T_FieldSelect:
    1293             :         case T_FieldStore:
    1294             :         case T_NamedArgExpr:
    1295             :         case T_BoolExpr:
    1296             :         case T_RelabelType:
    1297             :         case T_CollateExpr:
    1298             :         case T_CaseExpr:
    1299             :         case T_CaseTestExpr:
    1300             :         case T_RowExpr:
    1301             :         case T_SQLValueFunction:
    1302             :         case T_NullTest:
    1303             :         case T_BooleanTest:
    1304             :         case T_NextValueExpr:
    1305             :         case T_ReturningExpr:
    1306             :         case T_List:
    1307             : 
    1308             :             /*
    1309             :              * We know these node types don't contain function calls; but
    1310             :              * something further down in the node tree might.
    1311             :              */
    1312        6846 :             break;
    1313             : 
    1314        6094 :         case T_FuncExpr:
    1315             :         case T_OpExpr:
    1316             :         case T_DistinctExpr:
    1317             :         case T_NullIfExpr:
    1318             :         case T_ScalarArrayOpExpr:
    1319             :         case T_CoerceViaIO:
    1320             :         case T_ArrayCoerceExpr:
    1321             : 
    1322             :             /*
    1323             :              * If node contains a leaky function call, and there's any Var
    1324             :              * underneath it, reject.
    1325             :              */
    1326        6094 :             if (check_functions_in_node(node, contain_leaked_vars_checker,
    1327        2654 :                                         context) &&
    1328        2654 :                 contain_var_clause(node))
    1329        2598 :                 return true;
    1330        3496 :             break;
    1331             : 
    1332           0 :         case T_SubscriptingRef:
    1333             :             {
    1334           0 :                 SubscriptingRef *sbsref = (SubscriptingRef *) node;
    1335             :                 const SubscriptRoutines *sbsroutines;
    1336             : 
    1337             :                 /* Consult the subscripting support method info */
    1338           0 :                 sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype,
    1339             :                                                       NULL);
    1340           0 :                 if (!sbsroutines ||
    1341           0 :                     !(sbsref->refassgnexpr != NULL ?
    1342           0 :                       sbsroutines->store_leakproof :
    1343           0 :                       sbsroutines->fetch_leakproof))
    1344             :                 {
    1345             :                     /* Node is leaky, so reject if it contains Vars */
    1346           0 :                     if (contain_var_clause(node))
    1347           0 :                         return true;
    1348             :                 }
    1349             :             }
    1350           0 :             break;
    1351             : 
    1352           0 :         case T_RowCompareExpr:
    1353             :             {
    1354             :                 /*
    1355             :                  * It's worth special-casing this because a leaky comparison
    1356             :                  * function only compromises one pair of row elements, which
    1357             :                  * might not contain Vars while others do.
    1358             :                  */
    1359           0 :                 RowCompareExpr *rcexpr = (RowCompareExpr *) node;
    1360             :                 ListCell   *opid;
    1361             :                 ListCell   *larg;
    1362             :                 ListCell   *rarg;
    1363             : 
    1364           0 :                 forthree(opid, rcexpr->opnos,
    1365             :                          larg, rcexpr->largs,
    1366             :                          rarg, rcexpr->rargs)
    1367             :                 {
    1368           0 :                     Oid         funcid = get_opcode(lfirst_oid(opid));
    1369             : 
    1370           0 :                     if (!get_func_leakproof(funcid) &&
    1371           0 :                         (contain_var_clause((Node *) lfirst(larg)) ||
    1372           0 :                          contain_var_clause((Node *) lfirst(rarg))))
    1373           0 :                         return true;
    1374             :                 }
    1375             :             }
    1376           0 :             break;
    1377             : 
    1378           0 :         case T_MinMaxExpr:
    1379             :             {
    1380             :                 /*
    1381             :                  * MinMaxExpr is leakproof if the comparison function it calls
    1382             :                  * is leakproof.
    1383             :                  */
    1384           0 :                 MinMaxExpr *minmaxexpr = (MinMaxExpr *) node;
    1385             :                 TypeCacheEntry *typentry;
    1386             :                 bool        leakproof;
    1387             : 
    1388             :                 /* Look up the btree comparison function for the datatype */
    1389           0 :                 typentry = lookup_type_cache(minmaxexpr->minmaxtype,
    1390             :                                              TYPECACHE_CMP_PROC);
    1391           0 :                 if (OidIsValid(typentry->cmp_proc))
    1392           0 :                     leakproof = get_func_leakproof(typentry->cmp_proc);
    1393             :                 else
    1394             :                 {
    1395             :                     /*
    1396             :                      * The executor will throw an error, but here we just
    1397             :                      * treat the missing function as leaky.
    1398             :                      */
    1399           0 :                     leakproof = false;
    1400             :                 }
    1401             : 
    1402           0 :                 if (!leakproof &&
    1403           0 :                     contain_var_clause((Node *) minmaxexpr->args))
    1404           0 :                     return true;
    1405             :             }
    1406           0 :             break;
    1407             : 
    1408          42 :         case T_CurrentOfExpr:
    1409             : 
    1410             :             /*
    1411             :              * WHERE CURRENT OF doesn't contain leaky function calls.
    1412             :              * Moreover, it is essential that this is considered non-leaky,
    1413             :              * since the planner must always generate a TID scan when CURRENT
    1414             :              * OF is present -- cf. cost_tidscan.
    1415             :              */
    1416          42 :             return false;
    1417             : 
    1418          30 :         default:
    1419             : 
    1420             :             /*
    1421             :              * If we don't recognize the node tag, assume it might be leaky.
    1422             :              * This prevents an unexpected security hole if someone adds a new
    1423             :              * node type that can call a function.
    1424             :              */
    1425          30 :             return true;
    1426             :     }
    1427       10342 :     return expression_tree_walker(node, contain_leaked_vars_walker,
    1428             :                                   context);
    1429             : }
    1430             : 
    1431             : /*
    1432             :  * find_nonnullable_rels
    1433             :  *      Determine which base rels are forced nonnullable by given clause.
    1434             :  *
    1435             :  * Returns the set of all Relids that are referenced in the clause in such
    1436             :  * a way that the clause cannot possibly return TRUE if any of these Relids
    1437             :  * is an all-NULL row.  (It is OK to err on the side of conservatism; hence
    1438             :  * the analysis here is simplistic.)
    1439             :  *
    1440             :  * The semantics here are subtly different from contain_nonstrict_functions:
    1441             :  * that function is concerned with NULL results from arbitrary expressions,
    1442             :  * but here we assume that the input is a Boolean expression, and wish to
    1443             :  * see if NULL inputs will provably cause a FALSE-or-NULL result.  We expect
    1444             :  * the expression to have been AND/OR flattened and converted to implicit-AND
    1445             :  * format.
    1446             :  *
    1447             :  * Note: this function is largely duplicative of find_nonnullable_vars().
    1448             :  * The reason not to simplify this function into a thin wrapper around
    1449             :  * find_nonnullable_vars() is that the tested conditions really are different:
    1450             :  * a clause like "t1.v1 IS NOT NULL OR t1.v2 IS NOT NULL" does not prove
    1451             :  * that either v1 or v2 can't be NULL, but it does prove that the t1 row
    1452             :  * as a whole can't be all-NULL.  Also, the behavior for PHVs is different.
    1453             :  *
    1454             :  * top_level is true while scanning top-level AND/OR structure; here, showing
    1455             :  * the result is either FALSE or NULL is good enough.  top_level is false when
    1456             :  * we have descended below a NOT or a strict function: now we must be able to
    1457             :  * prove that the subexpression goes to NULL.
    1458             :  *
    1459             :  * We don't use expression_tree_walker here because we don't want to descend
    1460             :  * through very many kinds of nodes; only the ones we can be sure are strict.
    1461             :  */
    1462             : Relids
    1463      103650 : find_nonnullable_rels(Node *clause)
    1464             : {
    1465      103650 :     return find_nonnullable_rels_walker(clause, true);
    1466             : }
    1467             : 
    1468             : static Relids
    1469      675048 : find_nonnullable_rels_walker(Node *node, bool top_level)
    1470             : {
    1471      675048 :     Relids      result = NULL;
    1472             :     ListCell   *l;
    1473             : 
    1474      675048 :     if (node == NULL)
    1475        6446 :         return NULL;
    1476      668602 :     if (IsA(node, Var))
    1477             :     {
    1478      215906 :         Var        *var = (Var *) node;
    1479             : 
    1480      215906 :         if (var->varlevelsup == 0)
    1481      215906 :             result = bms_make_singleton(var->varno);
    1482             :     }
    1483      452696 :     else if (IsA(node, List))
    1484             :     {
    1485             :         /*
    1486             :          * At top level, we are examining an implicit-AND list: if any of the
    1487             :          * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
    1488             :          * not at top level, we are examining the arguments of a strict
    1489             :          * function: if any of them produce NULL then the result of the
    1490             :          * function must be NULL.  So in both cases, the set of nonnullable
    1491             :          * rels is the union of those found in the arms, and we pass down the
    1492             :          * top_level flag unmodified.
    1493             :          */
    1494      652880 :         foreach(l, (List *) node)
    1495             :         {
    1496      414464 :             result = bms_join(result,
    1497      414464 :                               find_nonnullable_rels_walker(lfirst(l),
    1498             :                                                            top_level));
    1499             :         }
    1500             :     }
    1501      214280 :     else if (IsA(node, FuncExpr))
    1502             :     {
    1503        7216 :         FuncExpr   *expr = (FuncExpr *) node;
    1504             : 
    1505        7216 :         if (func_strict(expr->funcid))
    1506        7024 :             result = find_nonnullable_rels_walker((Node *) expr->args, false);
    1507             :     }
    1508      207064 :     else if (IsA(node, OpExpr))
    1509             :     {
    1510      121556 :         OpExpr     *expr = (OpExpr *) node;
    1511             : 
    1512      121556 :         set_opfuncid(expr);
    1513      121556 :         if (func_strict(expr->opfuncid))
    1514      121556 :             result = find_nonnullable_rels_walker((Node *) expr->args, false);
    1515             :     }
    1516       85508 :     else if (IsA(node, ScalarArrayOpExpr))
    1517             :     {
    1518        8874 :         ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
    1519             : 
    1520        8874 :         if (is_strict_saop(expr, true))
    1521        8874 :             result = find_nonnullable_rels_walker((Node *) expr->args, false);
    1522             :     }
    1523       76634 :     else if (IsA(node, BoolExpr))
    1524             :     {
    1525        7672 :         BoolExpr   *expr = (BoolExpr *) node;
    1526             : 
    1527        7672 :         switch (expr->boolop)
    1528             :         {
    1529         460 :             case AND_EXPR:
    1530             :                 /* At top level we can just recurse (to the List case) */
    1531         460 :                 if (top_level)
    1532             :                 {
    1533         460 :                     result = find_nonnullable_rels_walker((Node *) expr->args,
    1534             :                                                           top_level);
    1535         460 :                     break;
    1536             :                 }
    1537             : 
    1538             :                 /*
    1539             :                  * Below top level, even if one arm produces NULL, the result
    1540             :                  * could be FALSE (hence not NULL).  However, if *all* the
    1541             :                  * arms produce NULL then the result is NULL, so we can take
    1542             :                  * the intersection of the sets of nonnullable rels, just as
    1543             :                  * for OR.  Fall through to share code.
    1544             :                  */
    1545             :                 /* FALL THRU */
    1546             :             case OR_EXPR:
    1547             : 
    1548             :                 /*
    1549             :                  * OR is strict if all of its arms are, so we can take the
    1550             :                  * intersection of the sets of nonnullable rels for each arm.
    1551             :                  * This works for both values of top_level.
    1552             :                  */
    1553        8900 :                 foreach(l, expr->args)
    1554             :                 {
    1555             :                     Relids      subresult;
    1556             : 
    1557        7764 :                     subresult = find_nonnullable_rels_walker(lfirst(l),
    1558             :                                                              top_level);
    1559        7764 :                     if (result == NULL) /* first subresult? */
    1560        3914 :                         result = subresult;
    1561             :                     else
    1562        3850 :                         result = bms_int_members(result, subresult);
    1563             : 
    1564             :                     /*
    1565             :                      * If the intersection is empty, we can stop looking. This
    1566             :                      * also justifies the test for first-subresult above.
    1567             :                      */
    1568        7764 :                     if (bms_is_empty(result))
    1569        2778 :                         break;
    1570             :                 }
    1571        3914 :                 break;
    1572        3298 :             case NOT_EXPR:
    1573             :                 /* NOT will return null if its arg is null */
    1574        3298 :                 result = find_nonnullable_rels_walker((Node *) expr->args,
    1575             :                                                       false);
    1576        3298 :                 break;
    1577           0 :             default:
    1578           0 :                 elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
    1579             :                 break;
    1580             :         }
    1581             :     }
    1582       68962 :     else if (IsA(node, RelabelType))
    1583             :     {
    1584        4148 :         RelabelType *expr = (RelabelType *) node;
    1585             : 
    1586        4148 :         result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
    1587             :     }
    1588       64814 :     else if (IsA(node, CoerceViaIO))
    1589             :     {
    1590             :         /* not clear this is useful, but it can't hurt */
    1591         202 :         CoerceViaIO *expr = (CoerceViaIO *) node;
    1592             : 
    1593         202 :         result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
    1594             :     }
    1595       64612 :     else if (IsA(node, ArrayCoerceExpr))
    1596             :     {
    1597             :         /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
    1598           0 :         ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
    1599             : 
    1600           0 :         result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
    1601             :     }
    1602       64612 :     else if (IsA(node, ConvertRowtypeExpr))
    1603             :     {
    1604             :         /* not clear this is useful, but it can't hurt */
    1605           0 :         ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
    1606             : 
    1607           0 :         result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
    1608             :     }
    1609       64612 :     else if (IsA(node, CollateExpr))
    1610             :     {
    1611           0 :         CollateExpr *expr = (CollateExpr *) node;
    1612             : 
    1613           0 :         result = find_nonnullable_rels_walker((Node *) expr->arg, top_level);
    1614             :     }
    1615       64612 :     else if (IsA(node, NullTest))
    1616             :     {
    1617             :         /* IS NOT NULL can be considered strict, but only at top level */
    1618        4698 :         NullTest   *expr = (NullTest *) node;
    1619             : 
    1620        4698 :         if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
    1621        2938 :             result = find_nonnullable_rels_walker((Node *) expr->arg, false);
    1622             :     }
    1623       59914 :     else if (IsA(node, BooleanTest))
    1624             :     {
    1625             :         /* Boolean tests that reject NULL are strict at top level */
    1626         102 :         BooleanTest *expr = (BooleanTest *) node;
    1627             : 
    1628         102 :         if (top_level &&
    1629         102 :             (expr->booltesttype == IS_TRUE ||
    1630         102 :              expr->booltesttype == IS_FALSE ||
    1631           6 :              expr->booltesttype == IS_NOT_UNKNOWN))
    1632          96 :             result = find_nonnullable_rels_walker((Node *) expr->arg, false);
    1633             :     }
    1634       59812 :     else if (IsA(node, SubPlan))
    1635             :     {
    1636         124 :         SubPlan    *splan = (SubPlan *) node;
    1637             : 
    1638             :         /*
    1639             :          * For some types of SubPlan, we can infer strictness from Vars in the
    1640             :          * testexpr (the LHS of the original SubLink).
    1641             :          *
    1642             :          * For ANY_SUBLINK, if the subquery produces zero rows, the result is
    1643             :          * always FALSE.  If the subquery produces more than one row, the
    1644             :          * per-row results of the testexpr are combined using OR semantics.
    1645             :          * Hence ANY_SUBLINK can be strict only at top level, but there it's
    1646             :          * as strict as the testexpr is.
    1647             :          *
    1648             :          * For ROWCOMPARE_SUBLINK, if the subquery produces zero rows, the
    1649             :          * result is always NULL.  Otherwise, the result is as strict as the
    1650             :          * testexpr is.  So we can check regardless of top_level.
    1651             :          *
    1652             :          * We can't prove anything for other sublink types (in particular,
    1653             :          * note that ALL_SUBLINK will return TRUE if the subquery is empty).
    1654             :          */
    1655         124 :         if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
    1656          82 :             splan->subLinkType == ROWCOMPARE_SUBLINK)
    1657          42 :             result = find_nonnullable_rels_walker(splan->testexpr, top_level);
    1658             :     }
    1659       59688 :     else if (IsA(node, PlaceHolderVar))
    1660             :     {
    1661         532 :         PlaceHolderVar *phv = (PlaceHolderVar *) node;
    1662             : 
    1663             :         /*
    1664             :          * If the contained expression forces any rels non-nullable, so does
    1665             :          * the PHV.
    1666             :          */
    1667         532 :         result = find_nonnullable_rels_walker((Node *) phv->phexpr, top_level);
    1668             : 
    1669             :         /*
    1670             :          * If the PHV's syntactic scope is exactly one rel, it will be forced
    1671             :          * to be evaluated at that rel, and so it will behave like a Var of
    1672             :          * that rel: if the rel's entire output goes to null, so will the PHV.
    1673             :          * (If the syntactic scope is a join, we know that the PHV will go to
    1674             :          * null if the whole join does; but that is AND semantics while we
    1675             :          * need OR semantics for find_nonnullable_rels' result, so we can't do
    1676             :          * anything with the knowledge.)
    1677             :          */
    1678        1064 :         if (phv->phlevelsup == 0 &&
    1679         532 :             bms_membership(phv->phrels) == BMS_SINGLETON)
    1680         340 :             result = bms_add_members(result, phv->phrels);
    1681             :     }
    1682      668602 :     return result;
    1683             : }
    1684             : 
    1685             : /*
    1686             :  * find_nonnullable_vars
    1687             :  *      Determine which Vars are forced nonnullable by given clause.
    1688             :  *
    1689             :  * Returns the set of all level-zero Vars that are referenced in the clause in
    1690             :  * such a way that the clause cannot possibly return TRUE if any of these Vars
    1691             :  * is NULL.  (It is OK to err on the side of conservatism; hence the analysis
    1692             :  * here is simplistic.)
    1693             :  *
    1694             :  * The semantics here are subtly different from contain_nonstrict_functions:
    1695             :  * that function is concerned with NULL results from arbitrary expressions,
    1696             :  * but here we assume that the input is a Boolean expression, and wish to
    1697             :  * see if NULL inputs will provably cause a FALSE-or-NULL result.  We expect
    1698             :  * the expression to have been AND/OR flattened and converted to implicit-AND
    1699             :  * format.
    1700             :  *
    1701             :  * Attnos of the identified Vars are returned in a multibitmapset (a List of
    1702             :  * Bitmapsets).  List indexes correspond to relids (varnos), while the per-rel
    1703             :  * Bitmapsets hold varattnos offset by FirstLowInvalidHeapAttributeNumber.
    1704             :  *
    1705             :  * top_level is true while scanning top-level AND/OR structure; here, showing
    1706             :  * the result is either FALSE or NULL is good enough.  top_level is false when
    1707             :  * we have descended below a NOT or a strict function: now we must be able to
    1708             :  * prove that the subexpression goes to NULL.
    1709             :  *
    1710             :  * We don't use expression_tree_walker here because we don't want to descend
    1711             :  * through very many kinds of nodes; only the ones we can be sure are strict.
    1712             :  */
    1713             : List *
    1714       45338 : find_nonnullable_vars(Node *clause)
    1715             : {
    1716       45338 :     return find_nonnullable_vars_walker(clause, true);
    1717             : }
    1718             : 
    1719             : static List *
    1720      289940 : find_nonnullable_vars_walker(Node *node, bool top_level)
    1721             : {
    1722      289940 :     List       *result = NIL;
    1723             :     ListCell   *l;
    1724             : 
    1725      289940 :     if (node == NULL)
    1726         680 :         return NIL;
    1727      289260 :     if (IsA(node, Var))
    1728             :     {
    1729      107412 :         Var        *var = (Var *) node;
    1730             : 
    1731      107412 :         if (var->varlevelsup == 0)
    1732      107412 :             result = mbms_add_member(result,
    1733             :                                      var->varno,
    1734      107412 :                                      var->varattno - FirstLowInvalidHeapAttributeNumber);
    1735             :     }
    1736      181848 :     else if (IsA(node, List))
    1737             :     {
    1738             :         /*
    1739             :          * At top level, we are examining an implicit-AND list: if any of the
    1740             :          * arms produces FALSE-or-NULL then the result is FALSE-or-NULL. If
    1741             :          * not at top level, we are examining the arguments of a strict
    1742             :          * function: if any of them produce NULL then the result of the
    1743             :          * function must be NULL.  So in both cases, the set of nonnullable
    1744             :          * vars is the union of those found in the arms, and we pass down the
    1745             :          * top_level flag unmodified.
    1746             :          */
    1747      287734 :         foreach(l, (List *) node)
    1748             :         {
    1749      182016 :             result = mbms_add_members(result,
    1750      182016 :                                       find_nonnullable_vars_walker(lfirst(l),
    1751             :                                                                    top_level));
    1752             :         }
    1753             :     }
    1754       76130 :     else if (IsA(node, FuncExpr))
    1755             :     {
    1756         440 :         FuncExpr   *expr = (FuncExpr *) node;
    1757             : 
    1758         440 :         if (func_strict(expr->funcid))
    1759         416 :             result = find_nonnullable_vars_walker((Node *) expr->args, false);
    1760             :     }
    1761       75690 :     else if (IsA(node, OpExpr))
    1762             :     {
    1763       58870 :         OpExpr     *expr = (OpExpr *) node;
    1764             : 
    1765       58870 :         set_opfuncid(expr);
    1766       58870 :         if (func_strict(expr->opfuncid))
    1767       58870 :             result = find_nonnullable_vars_walker((Node *) expr->args, false);
    1768             :     }
    1769       16820 :     else if (IsA(node, ScalarArrayOpExpr))
    1770             :     {
    1771        1714 :         ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node;
    1772             : 
    1773        1714 :         if (is_strict_saop(expr, true))
    1774        1714 :             result = find_nonnullable_vars_walker((Node *) expr->args, false);
    1775             :     }
    1776       15106 :     else if (IsA(node, BoolExpr))
    1777             :     {
    1778         362 :         BoolExpr   *expr = (BoolExpr *) node;
    1779             : 
    1780         362 :         switch (expr->boolop)
    1781             :         {
    1782           0 :             case AND_EXPR:
    1783             : 
    1784             :                 /*
    1785             :                  * At top level we can just recurse (to the List case), since
    1786             :                  * the result should be the union of what we can prove in each
    1787             :                  * arm.
    1788             :                  */
    1789           0 :                 if (top_level)
    1790             :                 {
    1791           0 :                     result = find_nonnullable_vars_walker((Node *) expr->args,
    1792             :                                                           top_level);
    1793           0 :                     break;
    1794             :                 }
    1795             : 
    1796             :                 /*
    1797             :                  * Below top level, even if one arm produces NULL, the result
    1798             :                  * could be FALSE (hence not NULL).  However, if *all* the
    1799             :                  * arms produce NULL then the result is NULL, so we can take
    1800             :                  * the intersection of the sets of nonnullable vars, just as
    1801             :                  * for OR.  Fall through to share code.
    1802             :                  */
    1803             :                 /* FALL THRU */
    1804             :             case OR_EXPR:
    1805             : 
    1806             :                 /*
    1807             :                  * OR is strict if all of its arms are, so we can take the
    1808             :                  * intersection of the sets of nonnullable vars for each arm.
    1809             :                  * This works for both values of top_level.
    1810             :                  */
    1811         796 :                 foreach(l, expr->args)
    1812             :                 {
    1813             :                     List       *subresult;
    1814             : 
    1815         640 :                     subresult = find_nonnullable_vars_walker(lfirst(l),
    1816             :                                                              top_level);
    1817         640 :                     if (result == NIL)  /* first subresult? */
    1818         302 :                         result = subresult;
    1819             :                     else
    1820         338 :                         result = mbms_int_members(result, subresult);
    1821             : 
    1822             :                     /*
    1823             :                      * If the intersection is empty, we can stop looking. This
    1824             :                      * also justifies the test for first-subresult above.
    1825             :                      */
    1826         640 :                     if (result == NIL)
    1827         146 :                         break;
    1828             :                 }
    1829         302 :                 break;
    1830          60 :             case NOT_EXPR:
    1831             :                 /* NOT will return null if its arg is null */
    1832          60 :                 result = find_nonnullable_vars_walker((Node *) expr->args,
    1833             :                                                       false);
    1834          60 :                 break;
    1835           0 :             default:
    1836           0 :                 elog(ERROR, "unrecognized boolop: %d", (int) expr->boolop);
    1837             :                 break;
    1838             :         }
    1839             :     }
    1840       14744 :     else if (IsA(node, RelabelType))
    1841             :     {
    1842         594 :         RelabelType *expr = (RelabelType *) node;
    1843             : 
    1844         594 :         result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
    1845             :     }
    1846       14150 :     else if (IsA(node, CoerceViaIO))
    1847             :     {
    1848             :         /* not clear this is useful, but it can't hurt */
    1849         112 :         CoerceViaIO *expr = (CoerceViaIO *) node;
    1850             : 
    1851         112 :         result = find_nonnullable_vars_walker((Node *) expr->arg, false);
    1852             :     }
    1853       14038 :     else if (IsA(node, ArrayCoerceExpr))
    1854             :     {
    1855             :         /* ArrayCoerceExpr is strict at the array level; ignore elemexpr */
    1856           0 :         ArrayCoerceExpr *expr = (ArrayCoerceExpr *) node;
    1857             : 
    1858           0 :         result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
    1859             :     }
    1860       14038 :     else if (IsA(node, ConvertRowtypeExpr))
    1861             :     {
    1862             :         /* not clear this is useful, but it can't hurt */
    1863           0 :         ConvertRowtypeExpr *expr = (ConvertRowtypeExpr *) node;
    1864             : 
    1865           0 :         result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
    1866             :     }
    1867       14038 :     else if (IsA(node, CollateExpr))
    1868             :     {
    1869           0 :         CollateExpr *expr = (CollateExpr *) node;
    1870             : 
    1871           0 :         result = find_nonnullable_vars_walker((Node *) expr->arg, top_level);
    1872             :     }
    1873       14038 :     else if (IsA(node, NullTest))
    1874             :     {
    1875             :         /* IS NOT NULL can be considered strict, but only at top level */
    1876         260 :         NullTest   *expr = (NullTest *) node;
    1877             : 
    1878         260 :         if (top_level && expr->nulltesttype == IS_NOT_NULL && !expr->argisrow)
    1879          96 :             result = find_nonnullable_vars_walker((Node *) expr->arg, false);
    1880             :     }
    1881       13778 :     else if (IsA(node, BooleanTest))
    1882             :     {
    1883             :         /* Boolean tests that reject NULL are strict at top level */
    1884           0 :         BooleanTest *expr = (BooleanTest *) node;
    1885             : 
    1886           0 :         if (top_level &&
    1887           0 :             (expr->booltesttype == IS_TRUE ||
    1888           0 :              expr->booltesttype == IS_FALSE ||
    1889           0 :              expr->booltesttype == IS_NOT_UNKNOWN))
    1890           0 :             result = find_nonnullable_vars_walker((Node *) expr->arg, false);
    1891             :     }
    1892       13778 :     else if (IsA(node, SubPlan))
    1893             :     {
    1894          30 :         SubPlan    *splan = (SubPlan *) node;
    1895             : 
    1896             :         /* See analysis in find_nonnullable_rels_walker */
    1897          30 :         if ((top_level && splan->subLinkType == ANY_SUBLINK) ||
    1898           6 :             splan->subLinkType == ROWCOMPARE_SUBLINK)
    1899          24 :             result = find_nonnullable_vars_walker(splan->testexpr, top_level);
    1900             :     }
    1901       13748 :     else if (IsA(node, PlaceHolderVar))
    1902             :     {
    1903          60 :         PlaceHolderVar *phv = (PlaceHolderVar *) node;
    1904             : 
    1905          60 :         result = find_nonnullable_vars_walker((Node *) phv->phexpr, top_level);
    1906             :     }
    1907      289260 :     return result;
    1908             : }
    1909             : 
    1910             : /*
    1911             :  * find_forced_null_vars
    1912             :  *      Determine which Vars must be NULL for the given clause to return TRUE.
    1913             :  *
    1914             :  * This is the complement of find_nonnullable_vars: find the level-zero Vars
    1915             :  * that must be NULL for the clause to return TRUE.  (It is OK to err on the
    1916             :  * side of conservatism; hence the analysis here is simplistic.  In fact,
    1917             :  * we only detect simple "var IS NULL" tests at the top level.)
    1918             :  *
    1919             :  * As with find_nonnullable_vars, we return the varattnos of the identified
    1920             :  * Vars in a multibitmapset.
    1921             :  */
    1922             : List *
    1923      120788 : find_forced_null_vars(Node *node)
    1924             : {
    1925      120788 :     List       *result = NIL;
    1926             :     Var        *var;
    1927             :     ListCell   *l;
    1928             : 
    1929      120788 :     if (node == NULL)
    1930        5620 :         return NIL;
    1931             :     /* Check single-clause cases using subroutine */
    1932      115168 :     var = find_forced_null_var(node);
    1933      115168 :     if (var)
    1934             :     {
    1935        1322 :         result = mbms_add_member(result,
    1936             :                                  var->varno,
    1937        1322 :                                  var->varattno - FirstLowInvalidHeapAttributeNumber);
    1938             :     }
    1939             :     /* Otherwise, handle AND-conditions */
    1940      113846 :     else if (IsA(node, List))
    1941             :     {
    1942             :         /*
    1943             :          * At top level, we are examining an implicit-AND list: if any of the
    1944             :          * arms produces FALSE-or-NULL then the result is FALSE-or-NULL.
    1945             :          */
    1946      115168 :         foreach(l, (List *) node)
    1947             :         {
    1948       70170 :             result = mbms_add_members(result,
    1949       70170 :                                       find_forced_null_vars((Node *) lfirst(l)));
    1950             :         }
    1951             :     }
    1952       68848 :     else if (IsA(node, BoolExpr))
    1953             :     {
    1954        5546 :         BoolExpr   *expr = (BoolExpr *) node;
    1955             : 
    1956             :         /*
    1957             :          * We don't bother considering the OR case, because it's fairly
    1958             :          * unlikely anyone would write "v1 IS NULL OR v1 IS NULL". Likewise,
    1959             :          * the NOT case isn't worth expending code on.
    1960             :          */
    1961        5546 :         if (expr->boolop == AND_EXPR)
    1962             :         {
    1963             :             /* At top level we can just recurse (to the List case) */
    1964           0 :             result = find_forced_null_vars((Node *) expr->args);
    1965             :         }
    1966             :     }
    1967      115168 :     return result;
    1968             : }
    1969             : 
    1970             : /*
    1971             :  * find_forced_null_var
    1972             :  *      Return the Var forced null by the given clause, or NULL if it's
    1973             :  *      not an IS NULL-type clause.  For success, the clause must enforce
    1974             :  *      *only* nullness of the particular Var, not any other conditions.
    1975             :  *
    1976             :  * This is just the single-clause case of find_forced_null_vars(), without
    1977             :  * any allowance for AND conditions.  It's used by initsplan.c on individual
    1978             :  * qual clauses.  The reason for not just applying find_forced_null_vars()
    1979             :  * is that if an AND of an IS NULL clause with something else were to somehow
    1980             :  * survive AND/OR flattening, initsplan.c might get fooled into discarding
    1981             :  * the whole clause when only the IS NULL part of it had been proved redundant.
    1982             :  */
    1983             : Var *
    1984      600572 : find_forced_null_var(Node *node)
    1985             : {
    1986      600572 :     if (node == NULL)
    1987           0 :         return NULL;
    1988      600572 :     if (IsA(node, NullTest))
    1989             :     {
    1990             :         /* check for var IS NULL */
    1991       11056 :         NullTest   *expr = (NullTest *) node;
    1992             : 
    1993       11056 :         if (expr->nulltesttype == IS_NULL && !expr->argisrow)
    1994             :         {
    1995        4100 :             Var        *var = (Var *) expr->arg;
    1996             : 
    1997        4100 :             if (var && IsA(var, Var) &&
    1998        3980 :                 var->varlevelsup == 0)
    1999        3980 :                 return var;
    2000             :         }
    2001             :     }
    2002      589516 :     else if (IsA(node, BooleanTest))
    2003             :     {
    2004             :         /* var IS UNKNOWN is equivalent to var IS NULL */
    2005         592 :         BooleanTest *expr = (BooleanTest *) node;
    2006             : 
    2007         592 :         if (expr->booltesttype == IS_UNKNOWN)
    2008             :         {
    2009          42 :             Var        *var = (Var *) expr->arg;
    2010             : 
    2011          42 :             if (var && IsA(var, Var) &&
    2012          42 :                 var->varlevelsup == 0)
    2013          42 :                 return var;
    2014             :         }
    2015             :     }
    2016      596550 :     return NULL;
    2017             : }
    2018             : 
    2019             : /*
    2020             :  * Can we treat a ScalarArrayOpExpr as strict?
    2021             :  *
    2022             :  * If "falseOK" is true, then a "false" result can be considered strict,
    2023             :  * else we need to guarantee an actual NULL result for NULL input.
    2024             :  *
    2025             :  * "foo op ALL array" is strict if the op is strict *and* we can prove
    2026             :  * that the array input isn't an empty array.  We can check that
    2027             :  * for the cases of an array constant and an ARRAY[] construct.
    2028             :  *
    2029             :  * "foo op ANY array" is strict in the falseOK sense if the op is strict.
    2030             :  * If not falseOK, the test is the same as for "foo op ALL array".
    2031             :  */
    2032             : static bool
    2033       10588 : is_strict_saop(ScalarArrayOpExpr *expr, bool falseOK)
    2034             : {
    2035             :     Node       *rightop;
    2036             : 
    2037             :     /* The contained operator must be strict. */
    2038       10588 :     set_sa_opfuncid(expr);
    2039       10588 :     if (!func_strict(expr->opfuncid))
    2040           0 :         return false;
    2041             :     /* If ANY and falseOK, that's all we need to check. */
    2042       10588 :     if (expr->useOr && falseOK)
    2043       10428 :         return true;
    2044             :     /* Else, we have to see if the array is provably non-empty. */
    2045             :     Assert(list_length(expr->args) == 2);
    2046         160 :     rightop = (Node *) lsecond(expr->args);
    2047         160 :     if (rightop && IsA(rightop, Const))
    2048           0 :     {
    2049         160 :         Datum       arraydatum = ((Const *) rightop)->constvalue;
    2050         160 :         bool        arrayisnull = ((Const *) rightop)->constisnull;
    2051             :         ArrayType  *arrayval;
    2052             :         int         nitems;
    2053             : 
    2054         160 :         if (arrayisnull)
    2055           0 :             return false;
    2056         160 :         arrayval = DatumGetArrayTypeP(arraydatum);
    2057         160 :         nitems = ArrayGetNItems(ARR_NDIM(arrayval), ARR_DIMS(arrayval));
    2058         160 :         if (nitems > 0)
    2059         160 :             return true;
    2060             :     }
    2061           0 :     else if (rightop && IsA(rightop, ArrayExpr))
    2062             :     {
    2063           0 :         ArrayExpr  *arrayexpr = (ArrayExpr *) rightop;
    2064             : 
    2065           0 :         if (arrayexpr->elements != NIL && !arrayexpr->multidims)
    2066           0 :             return true;
    2067             :     }
    2068           0 :     return false;
    2069             : }
    2070             : 
    2071             : 
    2072             : /*****************************************************************************
    2073             :  *      Check for "pseudo-constant" clauses
    2074             :  *****************************************************************************/
    2075             : 
    2076             : /*
    2077             :  * is_pseudo_constant_clause
    2078             :  *    Detect whether an expression is "pseudo constant", ie, it contains no
    2079             :  *    variables of the current query level and no uses of volatile functions.
    2080             :  *    Such an expr is not necessarily a true constant: it can still contain
    2081             :  *    Params and outer-level Vars, not to mention functions whose results
    2082             :  *    may vary from one statement to the next.  However, the expr's value
    2083             :  *    will be constant over any one scan of the current query, so it can be
    2084             :  *    used as, eg, an indexscan key.  (Actually, the condition for indexscan
    2085             :  *    keys is weaker than this; see is_pseudo_constant_for_index().)
    2086             :  *
    2087             :  * CAUTION: this function omits to test for one very important class of
    2088             :  * not-constant expressions, namely aggregates (Aggrefs).  In current usage
    2089             :  * this is only applied to WHERE clauses and so a check for Aggrefs would be
    2090             :  * a waste of cycles; but be sure to also check contain_agg_clause() if you
    2091             :  * want to know about pseudo-constness in other contexts.  The same goes
    2092             :  * for window functions (WindowFuncs).
    2093             :  */
    2094             : bool
    2095        5832 : is_pseudo_constant_clause(Node *clause)
    2096             : {
    2097             :     /*
    2098             :      * We could implement this check in one recursive scan.  But since the
    2099             :      * check for volatile functions is both moderately expensive and unlikely
    2100             :      * to fail, it seems better to look for Vars first and only check for
    2101             :      * volatile functions if we find no Vars.
    2102             :      */
    2103        5832 :     if (!contain_var_clause(clause) &&
    2104        5832 :         !contain_volatile_functions(clause))
    2105        5832 :         return true;
    2106           0 :     return false;
    2107             : }
    2108             : 
    2109             : /*
    2110             :  * is_pseudo_constant_clause_relids
    2111             :  *    Same as above, except caller already has available the var membership
    2112             :  *    of the expression; this lets us avoid the contain_var_clause() scan.
    2113             :  */
    2114             : bool
    2115      455124 : is_pseudo_constant_clause_relids(Node *clause, Relids relids)
    2116             : {
    2117      455124 :     if (bms_is_empty(relids) &&
    2118      447384 :         !contain_volatile_functions(clause))
    2119      447384 :         return true;
    2120        7740 :     return false;
    2121             : }
    2122             : 
    2123             : 
    2124             : /*****************************************************************************
    2125             :  *                                                                           *
    2126             :  *      General clause-manipulating routines                                 *
    2127             :  *                                                                           *
    2128             :  *****************************************************************************/
    2129             : 
    2130             : /*
    2131             :  * NumRelids
    2132             :  *      (formerly clause_relids)
    2133             :  *
    2134             :  * Returns the number of different base relations referenced in 'clause'.
    2135             :  */
    2136             : int
    2137        1782 : NumRelids(PlannerInfo *root, Node *clause)
    2138             : {
    2139             :     int         result;
    2140        1782 :     Relids      varnos = pull_varnos(root, clause);
    2141             : 
    2142        1782 :     varnos = bms_del_members(varnos, root->outer_join_rels);
    2143        1782 :     result = bms_num_members(varnos);
    2144        1782 :     bms_free(varnos);
    2145        1782 :     return result;
    2146             : }
    2147             : 
    2148             : /*
    2149             :  * CommuteOpExpr: commute a binary operator clause
    2150             :  *
    2151             :  * XXX the clause is destructively modified!
    2152             :  */
    2153             : void
    2154       19954 : CommuteOpExpr(OpExpr *clause)
    2155             : {
    2156             :     Oid         opoid;
    2157             :     Node       *temp;
    2158             : 
    2159             :     /* Sanity checks: caller is at fault if these fail */
    2160       39908 :     if (!is_opclause(clause) ||
    2161       19954 :         list_length(clause->args) != 2)
    2162           0 :         elog(ERROR, "cannot commute non-binary-operator clause");
    2163             : 
    2164       19954 :     opoid = get_commutator(clause->opno);
    2165             : 
    2166       19954 :     if (!OidIsValid(opoid))
    2167           0 :         elog(ERROR, "could not find commutator for operator %u",
    2168             :              clause->opno);
    2169             : 
    2170             :     /*
    2171             :      * modify the clause in-place!
    2172             :      */
    2173       19954 :     clause->opno = opoid;
    2174       19954 :     clause->opfuncid = InvalidOid;
    2175             :     /* opresulttype, opretset, opcollid, inputcollid need not change */
    2176             : 
    2177       19954 :     temp = linitial(clause->args);
    2178       19954 :     linitial(clause->args) = lsecond(clause->args);
    2179       19954 :     lsecond(clause->args) = temp;
    2180       19954 : }
    2181             : 
    2182             : /*
    2183             :  * Helper for eval_const_expressions: check that datatype of an attribute
    2184             :  * is still what it was when the expression was parsed.  This is needed to
    2185             :  * guard against improper simplification after ALTER COLUMN TYPE.  (XXX we
    2186             :  * may well need to make similar checks elsewhere?)
    2187             :  *
    2188             :  * rowtypeid may come from a whole-row Var, and therefore it can be a domain
    2189             :  * over composite, but for this purpose we only care about checking the type
    2190             :  * of a contained field.
    2191             :  */
    2192             : static bool
    2193         706 : rowtype_field_matches(Oid rowtypeid, int fieldnum,
    2194             :                       Oid expectedtype, int32 expectedtypmod,
    2195             :                       Oid expectedcollation)
    2196             : {
    2197             :     TupleDesc   tupdesc;
    2198             :     Form_pg_attribute attr;
    2199             : 
    2200             :     /* No issue for RECORD, since there is no way to ALTER such a type */
    2201         706 :     if (rowtypeid == RECORDOID)
    2202          42 :         return true;
    2203         664 :     tupdesc = lookup_rowtype_tupdesc_domain(rowtypeid, -1, false);
    2204         664 :     if (fieldnum <= 0 || fieldnum > tupdesc->natts)
    2205             :     {
    2206           0 :         ReleaseTupleDesc(tupdesc);
    2207           0 :         return false;
    2208             :     }
    2209         664 :     attr = TupleDescAttr(tupdesc, fieldnum - 1);
    2210         664 :     if (attr->attisdropped ||
    2211         664 :         attr->atttypid != expectedtype ||
    2212         664 :         attr->atttypmod != expectedtypmod ||
    2213         664 :         attr->attcollation != expectedcollation)
    2214             :     {
    2215           0 :         ReleaseTupleDesc(tupdesc);
    2216           0 :         return false;
    2217             :     }
    2218         664 :     ReleaseTupleDesc(tupdesc);
    2219         664 :     return true;
    2220             : }
    2221             : 
    2222             : 
    2223             : /*--------------------
    2224             :  * eval_const_expressions
    2225             :  *
    2226             :  * Reduce any recognizably constant subexpressions of the given
    2227             :  * expression tree, for example "2 + 2" => "4".  More interestingly,
    2228             :  * we can reduce certain boolean expressions even when they contain
    2229             :  * non-constant subexpressions: "x OR true" => "true" no matter what
    2230             :  * the subexpression x is.  (XXX We assume that no such subexpression
    2231             :  * will have important side-effects, which is not necessarily a good
    2232             :  * assumption in the presence of user-defined functions; do we need a
    2233             :  * pg_proc flag that prevents discarding the execution of a function?)
    2234             :  *
    2235             :  * We do understand that certain functions may deliver non-constant
    2236             :  * results even with constant inputs, "nextval()" being the classic
    2237             :  * example.  Functions that are not marked "immutable" in pg_proc
    2238             :  * will not be pre-evaluated here, although we will reduce their
    2239             :  * arguments as far as possible.
    2240             :  *
    2241             :  * Whenever a function is eliminated from the expression by means of
    2242             :  * constant-expression evaluation or inlining, we add the function to
    2243             :  * root->glob->invalItems.  This ensures the plan is known to depend on
    2244             :  * such functions, even though they aren't referenced anymore.
    2245             :  *
    2246             :  * We assume that the tree has already been type-checked and contains
    2247             :  * only operators and functions that are reasonable to try to execute.
    2248             :  *
    2249             :  * NOTE: "root" can be passed as NULL if the caller never wants to do any
    2250             :  * Param substitutions nor receive info about inlined functions nor reduce
    2251             :  * NullTest for Vars to constant true or constant false.
    2252             :  *
    2253             :  * NOTE: the planner assumes that this will always flatten nested AND and
    2254             :  * OR clauses into N-argument form.  See comments in prepqual.c.
    2255             :  *
    2256             :  * NOTE: another critical effect is that any function calls that require
    2257             :  * default arguments will be expanded, and named-argument calls will be
    2258             :  * converted to positional notation.  The executor won't handle either.
    2259             :  *--------------------
    2260             :  */
    2261             : Node *
    2262     1214676 : eval_const_expressions(PlannerInfo *root, Node *node)
    2263             : {
    2264             :     eval_const_expressions_context context;
    2265             : 
    2266     1214676 :     if (root)
    2267      967122 :         context.boundParams = root->glob->boundParams;    /* bound Params */
    2268             :     else
    2269      247554 :         context.boundParams = NULL;
    2270     1214676 :     context.root = root;        /* for inlined-function dependencies */
    2271     1214676 :     context.active_fns = NIL;   /* nothing being recursively simplified */
    2272     1214676 :     context.case_val = NULL;    /* no CASE being examined */
    2273     1214676 :     context.estimate = false;   /* safe transformations only */
    2274     1214676 :     return eval_const_expressions_mutator(node, &context);
    2275             : }
    2276             : 
    2277             : #define MIN_ARRAY_SIZE_FOR_HASHED_SAOP 9
    2278             : /*--------------------
    2279             :  * convert_saop_to_hashed_saop
    2280             :  *
    2281             :  * Recursively search 'node' for ScalarArrayOpExprs and fill in the hash
    2282             :  * function for any ScalarArrayOpExpr that looks like it would be useful to
    2283             :  * evaluate using a hash table rather than a linear search.
    2284             :  *
    2285             :  * We'll use a hash table if all of the following conditions are met:
    2286             :  * 1. The 2nd argument of the array contain only Consts.
    2287             :  * 2. useOr is true or there is a valid negator operator for the
    2288             :  *    ScalarArrayOpExpr's opno.
    2289             :  * 3. There's valid hash function for both left and righthand operands and
    2290             :  *    these hash functions are the same.
    2291             :  * 4. If the array contains enough elements for us to consider it to be
    2292             :  *    worthwhile using a hash table rather than a linear search.
    2293             :  */
    2294             : void
    2295      842100 : convert_saop_to_hashed_saop(Node *node)
    2296             : {
    2297      842100 :     (void) convert_saop_to_hashed_saop_walker(node, NULL);
    2298      842100 : }
    2299             : 
    2300             : static bool
    2301     6051648 : convert_saop_to_hashed_saop_walker(Node *node, void *context)
    2302             : {
    2303     6051648 :     if (node == NULL)
    2304      132008 :         return false;
    2305             : 
    2306     5919640 :     if (IsA(node, ScalarArrayOpExpr))
    2307             :     {
    2308       32792 :         ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) node;
    2309       32792 :         Expr       *arrayarg = (Expr *) lsecond(saop->args);
    2310             :         Oid         lefthashfunc;
    2311             :         Oid         righthashfunc;
    2312             : 
    2313       32792 :         if (arrayarg && IsA(arrayarg, Const) &&
    2314       17782 :             !((Const *) arrayarg)->constisnull)
    2315             :         {
    2316       17752 :             if (saop->useOr)
    2317             :             {
    2318       15406 :                 if (get_op_hash_functions(saop->opno, &lefthashfunc, &righthashfunc) &&
    2319       15072 :                     lefthashfunc == righthashfunc)
    2320             :                 {
    2321       15046 :                     Datum       arrdatum = ((Const *) arrayarg)->constvalue;
    2322       15046 :                     ArrayType  *arr = (ArrayType *) DatumGetPointer(arrdatum);
    2323             :                     int         nitems;
    2324             : 
    2325             :                     /*
    2326             :                      * Only fill in the hash functions if the array looks
    2327             :                      * large enough for it to be worth hashing instead of
    2328             :                      * doing a linear search.
    2329             :                      */
    2330       15046 :                     nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
    2331             : 
    2332       15046 :                     if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
    2333             :                     {
    2334             :                         /* Looks good. Fill in the hash functions */
    2335         464 :                         saop->hashfuncid = lefthashfunc;
    2336             :                     }
    2337       17222 :                     return false;
    2338             :                 }
    2339             :             }
    2340             :             else                /* !saop->useOr */
    2341             :             {
    2342        2346 :                 Oid         negator = get_negator(saop->opno);
    2343             : 
    2344             :                 /*
    2345             :                  * Check if this is a NOT IN using an operator whose negator
    2346             :                  * is hashable.  If so we can still build a hash table and
    2347             :                  * just ensure the lookup items are not in the hash table.
    2348             :                  */
    2349        4692 :                 if (OidIsValid(negator) &&
    2350        2346 :                     get_op_hash_functions(negator, &lefthashfunc, &righthashfunc) &&
    2351        2176 :                     lefthashfunc == righthashfunc)
    2352             :                 {
    2353        2176 :                     Datum       arrdatum = ((Const *) arrayarg)->constvalue;
    2354        2176 :                     ArrayType  *arr = (ArrayType *) DatumGetPointer(arrdatum);
    2355             :                     int         nitems;
    2356             : 
    2357             :                     /*
    2358             :                      * Only fill in the hash functions if the array looks
    2359             :                      * large enough for it to be worth hashing instead of
    2360             :                      * doing a linear search.
    2361             :                      */
    2362        2176 :                     nitems = ArrayGetNItems(ARR_NDIM(arr), ARR_DIMS(arr));
    2363             : 
    2364        2176 :                     if (nitems >= MIN_ARRAY_SIZE_FOR_HASHED_SAOP)
    2365             :                     {
    2366             :                         /* Looks good. Fill in the hash functions */
    2367          70 :                         saop->hashfuncid = lefthashfunc;
    2368             : 
    2369             :                         /*
    2370             :                          * Also set the negfuncid.  The executor will need
    2371             :                          * that to perform hashtable lookups.
    2372             :                          */
    2373          70 :                         saop->negfuncid = get_opcode(negator);
    2374             :                     }
    2375        2176 :                     return false;
    2376             :                 }
    2377             :             }
    2378             :         }
    2379             :     }
    2380             : 
    2381     5902418 :     return expression_tree_walker(node, convert_saop_to_hashed_saop_walker, NULL);
    2382             : }
    2383             : 
    2384             : 
    2385             : /*--------------------
    2386             :  * estimate_expression_value
    2387             :  *
    2388             :  * This function attempts to estimate the value of an expression for
    2389             :  * planning purposes.  It is in essence a more aggressive version of
    2390             :  * eval_const_expressions(): we will perform constant reductions that are
    2391             :  * not necessarily 100% safe, but are reasonable for estimation purposes.
    2392             :  *
    2393             :  * Currently the extra steps that are taken in this mode are:
    2394             :  * 1. Substitute values for Params, where a bound Param value has been made
    2395             :  *    available by the caller of planner(), even if the Param isn't marked
    2396             :  *    constant.  This effectively means that we plan using the first supplied
    2397             :  *    value of the Param.
    2398             :  * 2. Fold stable, as well as immutable, functions to constants.
    2399             :  * 3. Reduce PlaceHolderVar nodes to their contained expressions.
    2400             :  *--------------------
    2401             :  */
    2402             : Node *
    2403      881962 : estimate_expression_value(PlannerInfo *root, Node *node)
    2404             : {
    2405             :     eval_const_expressions_context context;
    2406             : 
    2407      881962 :     context.boundParams = root->glob->boundParams;    /* bound Params */
    2408             :     /* we do not need to mark the plan as depending on inlined functions */
    2409      881962 :     context.root = NULL;
    2410      881962 :     context.active_fns = NIL;   /* nothing being recursively simplified */
    2411      881962 :     context.case_val = NULL;    /* no CASE being examined */
    2412      881962 :     context.estimate = true;    /* unsafe transformations OK */
    2413      881962 :     return eval_const_expressions_mutator(node, &context);
    2414             : }
    2415             : 
    2416             : /*
    2417             :  * The generic case in eval_const_expressions_mutator is to recurse using
    2418             :  * expression_tree_mutator, which will copy the given node unchanged but
    2419             :  * const-simplify its arguments (if any) as far as possible.  If the node
    2420             :  * itself does immutable processing, and each of its arguments were reduced
    2421             :  * to a Const, we can then reduce it to a Const using evaluate_expr.  (Some
    2422             :  * node types need more complicated logic; for example, a CASE expression
    2423             :  * might be reducible to a constant even if not all its subtrees are.)
    2424             :  */
    2425             : #define ece_generic_processing(node) \
    2426             :     expression_tree_mutator((Node *) (node), eval_const_expressions_mutator, \
    2427             :                             context)
    2428             : 
    2429             : /*
    2430             :  * Check whether all arguments of the given node were reduced to Consts.
    2431             :  * By going directly to expression_tree_walker, contain_non_const_walker
    2432             :  * is not applied to the node itself, only to its children.
    2433             :  */
    2434             : #define ece_all_arguments_const(node) \
    2435             :     (!expression_tree_walker((Node *) (node), contain_non_const_walker, NULL))
    2436             : 
    2437             : /* Generic macro for applying evaluate_expr */
    2438             : #define ece_evaluate_expr(node) \
    2439             :     ((Node *) evaluate_expr((Expr *) (node), \
    2440             :                             exprType((Node *) (node)), \
    2441             :                             exprTypmod((Node *) (node)), \
    2442             :                             exprCollation((Node *) (node))))
    2443             : 
    2444             : /*
    2445             :  * Recursive guts of eval_const_expressions/estimate_expression_value
    2446             :  */
    2447             : static Node *
    2448     9015380 : eval_const_expressions_mutator(Node *node,
    2449             :                                eval_const_expressions_context *context)
    2450             : {
    2451             : 
    2452             :     /* since this function recurses, it could be driven to stack overflow */
    2453     9015380 :     check_stack_depth();
    2454             : 
    2455     9015380 :     if (node == NULL)
    2456      371684 :         return NULL;
    2457     8643696 :     switch (nodeTag(node))
    2458             :     {
    2459      146830 :         case T_Param:
    2460             :             {
    2461      146830 :                 Param      *param = (Param *) node;
    2462      146830 :                 ParamListInfo paramLI = context->boundParams;
    2463             : 
    2464             :                 /* Look to see if we've been given a value for this Param */
    2465      146830 :                 if (param->paramkind == PARAM_EXTERN &&
    2466       53412 :                     paramLI != NULL &&
    2467       53412 :                     param->paramid > 0 &&
    2468       53412 :                     param->paramid <= paramLI->numParams)
    2469             :                 {
    2470             :                     ParamExternData *prm;
    2471             :                     ParamExternData prmdata;
    2472             : 
    2473             :                     /*
    2474             :                      * Give hook a chance in case parameter is dynamic.  Tell
    2475             :                      * it that this fetch is speculative, so it should avoid
    2476             :                      * erroring out if parameter is unavailable.
    2477             :                      */
    2478       53412 :                     if (paramLI->paramFetch != NULL)
    2479        7432 :                         prm = paramLI->paramFetch(paramLI, param->paramid,
    2480             :                                                   true, &prmdata);
    2481             :                     else
    2482       45980 :                         prm = &paramLI->params[param->paramid - 1];
    2483             : 
    2484             :                     /*
    2485             :                      * We don't just check OidIsValid, but insist that the
    2486             :                      * fetched type match the Param, just in case the hook did
    2487             :                      * something unexpected.  No need to throw an error here
    2488             :                      * though; leave that for runtime.
    2489             :                      */
    2490       53412 :                     if (OidIsValid(prm->ptype) &&
    2491       53412 :                         prm->ptype == param->paramtype)
    2492             :                     {
    2493             :                         /* OK to substitute parameter value? */
    2494       53410 :                         if (context->estimate ||
    2495       53410 :                             (prm->pflags & PARAM_FLAG_CONST))
    2496             :                         {
    2497             :                             /*
    2498             :                              * Return a Const representing the param value.
    2499             :                              * Must copy pass-by-ref datatypes, since the
    2500             :                              * Param might be in a memory context
    2501             :                              * shorter-lived than our output plan should be.
    2502             :                              */
    2503             :                             int16       typLen;
    2504             :                             bool        typByVal;
    2505             :                             Datum       pval;
    2506             :                             Const      *con;
    2507             : 
    2508       53410 :                             get_typlenbyval(param->paramtype,
    2509             :                                             &typLen, &typByVal);
    2510       53410 :                             if (prm->isnull || typByVal)
    2511       35216 :                                 pval = prm->value;
    2512             :                             else
    2513       18194 :                                 pval = datumCopy(prm->value, typByVal, typLen);
    2514       53410 :                             con = makeConst(param->paramtype,
    2515             :                                             param->paramtypmod,
    2516             :                                             param->paramcollid,
    2517             :                                             (int) typLen,
    2518             :                                             pval,
    2519       53410 :                                             prm->isnull,
    2520             :                                             typByVal);
    2521       53410 :                             con->location = param->location;
    2522       53410 :                             return (Node *) con;
    2523             :                         }
    2524             :                     }
    2525             :                 }
    2526             : 
    2527             :                 /*
    2528             :                  * Not replaceable, so just copy the Param (no need to
    2529             :                  * recurse)
    2530             :                  */
    2531       93420 :                 return (Node *) copyObject(param);
    2532             :             }
    2533        3266 :         case T_WindowFunc:
    2534             :             {
    2535        3266 :                 WindowFunc *expr = (WindowFunc *) node;
    2536        3266 :                 Oid         funcid = expr->winfnoid;
    2537             :                 List       *args;
    2538             :                 Expr       *aggfilter;
    2539             :                 HeapTuple   func_tuple;
    2540             :                 WindowFunc *newexpr;
    2541             : 
    2542             :                 /*
    2543             :                  * We can't really simplify a WindowFunc node, but we mustn't
    2544             :                  * just fall through to the default processing, because we
    2545             :                  * have to apply expand_function_arguments to its argument
    2546             :                  * list.  That takes care of inserting default arguments and
    2547             :                  * expanding named-argument notation.
    2548             :                  */
    2549        3266 :                 func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
    2550        3266 :                 if (!HeapTupleIsValid(func_tuple))
    2551           0 :                     elog(ERROR, "cache lookup failed for function %u", funcid);
    2552             : 
    2553        3266 :                 args = expand_function_arguments(expr->args,
    2554             :                                                  false, expr->wintype,
    2555             :                                                  func_tuple);
    2556             : 
    2557        3266 :                 ReleaseSysCache(func_tuple);
    2558             : 
    2559             :                 /* Now, recursively simplify the args (which are a List) */
    2560             :                 args = (List *)
    2561        3266 :                     expression_tree_mutator((Node *) args,
    2562             :                                             eval_const_expressions_mutator,
    2563             :                                             context);
    2564             :                 /* ... and the filter expression, which isn't */
    2565             :                 aggfilter = (Expr *)
    2566        3266 :                     eval_const_expressions_mutator((Node *) expr->aggfilter,
    2567             :                                                    context);
    2568             : 
    2569             :                 /* And build the replacement WindowFunc node */
    2570        3266 :                 newexpr = makeNode(WindowFunc);
    2571        3266 :                 newexpr->winfnoid = expr->winfnoid;
    2572        3266 :                 newexpr->wintype = expr->wintype;
    2573        3266 :                 newexpr->wincollid = expr->wincollid;
    2574        3266 :                 newexpr->inputcollid = expr->inputcollid;
    2575        3266 :                 newexpr->args = args;
    2576        3266 :                 newexpr->aggfilter = aggfilter;
    2577        3266 :                 newexpr->runCondition = expr->runCondition;
    2578        3266 :                 newexpr->winref = expr->winref;
    2579        3266 :                 newexpr->winstar = expr->winstar;
    2580        3266 :                 newexpr->winagg = expr->winagg;
    2581        3266 :                 newexpr->location = expr->location;
    2582             : 
    2583        3266 :                 return (Node *) newexpr;
    2584             :             }
    2585      536216 :         case T_FuncExpr:
    2586             :             {
    2587      536216 :                 FuncExpr   *expr = (FuncExpr *) node;
    2588      536216 :                 List       *args = expr->args;
    2589             :                 Expr       *simple;
    2590             :                 FuncExpr   *newexpr;
    2591             : 
    2592             :                 /*
    2593             :                  * Code for op/func reduction is pretty bulky, so split it out
    2594             :                  * as a separate function.  Note: exprTypmod normally returns
    2595             :                  * -1 for a FuncExpr, but not when the node is recognizably a
    2596             :                  * length coercion; we want to preserve the typmod in the
    2597             :                  * eventual Const if so.
    2598             :                  */
    2599      536216 :                 simple = simplify_function(expr->funcid,
    2600             :                                            expr->funcresulttype,
    2601             :                                            exprTypmod(node),
    2602             :                                            expr->funccollid,
    2603             :                                            expr->inputcollid,
    2604             :                                            &args,
    2605      536216 :                                            expr->funcvariadic,
    2606             :                                            true,
    2607             :                                            true,
    2608             :                                            context);
    2609      533450 :                 if (simple)     /* successfully simplified it */
    2610      154724 :                     return (Node *) simple;
    2611             : 
    2612             :                 /*
    2613             :                  * The expression cannot be simplified any further, so build
    2614             :                  * and return a replacement FuncExpr node using the
    2615             :                  * possibly-simplified arguments.  Note that we have also
    2616             :                  * converted the argument list to positional notation.
    2617             :                  */
    2618      378726 :                 newexpr = makeNode(FuncExpr);
    2619      378726 :                 newexpr->funcid = expr->funcid;
    2620      378726 :                 newexpr->funcresulttype = expr->funcresulttype;
    2621      378726 :                 newexpr->funcretset = expr->funcretset;
    2622      378726 :                 newexpr->funcvariadic = expr->funcvariadic;
    2623      378726 :                 newexpr->funcformat = expr->funcformat;
    2624      378726 :                 newexpr->funccollid = expr->funccollid;
    2625      378726 :                 newexpr->inputcollid = expr->inputcollid;
    2626      378726 :                 newexpr->args = args;
    2627      378726 :                 newexpr->location = expr->location;
    2628      378726 :                 return (Node *) newexpr;
    2629             :             }
    2630      684368 :         case T_OpExpr:
    2631             :             {
    2632      684368 :                 OpExpr     *expr = (OpExpr *) node;
    2633      684368 :                 List       *args = expr->args;
    2634             :                 Expr       *simple;
    2635             :                 OpExpr     *newexpr;
    2636             : 
    2637             :                 /*
    2638             :                  * Need to get OID of underlying function.  Okay to scribble
    2639             :                  * on input to this extent.
    2640             :                  */
    2641      684368 :                 set_opfuncid(expr);
    2642             : 
    2643             :                 /*
    2644             :                  * Code for op/func reduction is pretty bulky, so split it out
    2645             :                  * as a separate function.
    2646             :                  */
    2647      684368 :                 simple = simplify_function(expr->opfuncid,
    2648             :                                            expr->opresulttype, -1,
    2649             :                                            expr->opcollid,
    2650             :                                            expr->inputcollid,
    2651             :                                            &args,
    2652             :                                            false,
    2653             :                                            true,
    2654             :                                            true,
    2655             :                                            context);
    2656      683186 :                 if (simple)     /* successfully simplified it */
    2657       22438 :                     return (Node *) simple;
    2658             : 
    2659             :                 /*
    2660             :                  * If the operator is boolean equality or inequality, we know
    2661             :                  * how to simplify cases involving one constant and one
    2662             :                  * non-constant argument.
    2663             :                  */
    2664      660748 :                 if (expr->opno == BooleanEqualOperator ||
    2665      659612 :                     expr->opno == BooleanNotEqualOperator)
    2666             :                 {
    2667        1304 :                     simple = (Expr *) simplify_boolean_equality(expr->opno,
    2668             :                                                                 args);
    2669        1304 :                     if (simple) /* successfully simplified it */
    2670        1042 :                         return (Node *) simple;
    2671             :                 }
    2672             : 
    2673             :                 /*
    2674             :                  * The expression cannot be simplified any further, so build
    2675             :                  * and return a replacement OpExpr node using the
    2676             :                  * possibly-simplified arguments.
    2677             :                  */
    2678      659706 :                 newexpr = makeNode(OpExpr);
    2679      659706 :                 newexpr->opno = expr->opno;
    2680      659706 :                 newexpr->opfuncid = expr->opfuncid;
    2681      659706 :                 newexpr->opresulttype = expr->opresulttype;
    2682      659706 :                 newexpr->opretset = expr->opretset;
    2683      659706 :                 newexpr->opcollid = expr->opcollid;
    2684      659706 :                 newexpr->inputcollid = expr->inputcollid;
    2685      659706 :                 newexpr->args = args;
    2686      659706 :                 newexpr->location = expr->location;
    2687      659706 :                 return (Node *) newexpr;
    2688             :             }
    2689        1204 :         case T_DistinctExpr:
    2690             :             {
    2691        1204 :                 DistinctExpr *expr = (DistinctExpr *) node;
    2692             :                 List       *args;
    2693             :                 ListCell   *arg;
    2694        1204 :                 bool        has_null_input = false;
    2695        1204 :                 bool        all_null_input = true;
    2696        1204 :                 bool        has_nonconst_input = false;
    2697             :                 Expr       *simple;
    2698             :                 DistinctExpr *newexpr;
    2699             : 
    2700             :                 /*
    2701             :                  * Reduce constants in the DistinctExpr's arguments.  We know
    2702             :                  * args is either NIL or a List node, so we can call
    2703             :                  * expression_tree_mutator directly rather than recursing to
    2704             :                  * self.
    2705             :                  */
    2706        1204 :                 args = (List *) expression_tree_mutator((Node *) expr->args,
    2707             :                                                         eval_const_expressions_mutator,
    2708             :                                                         context);
    2709             : 
    2710             :                 /*
    2711             :                  * We must do our own check for NULLs because DistinctExpr has
    2712             :                  * different results for NULL input than the underlying
    2713             :                  * operator does.
    2714             :                  */
    2715        3612 :                 foreach(arg, args)
    2716             :                 {
    2717        2408 :                     if (IsA(lfirst(arg), Const))
    2718             :                     {
    2719         354 :                         has_null_input |= ((Const *) lfirst(arg))->constisnull;
    2720         354 :                         all_null_input &= ((Const *) lfirst(arg))->constisnull;
    2721             :                     }
    2722             :                     else
    2723        2054 :                         has_nonconst_input = true;
    2724             :                 }
    2725             : 
    2726             :                 /* all constants? then can optimize this out */
    2727        1204 :                 if (!has_nonconst_input)
    2728             :                 {
    2729             :                     /* all nulls? then not distinct */
    2730          54 :                     if (all_null_input)
    2731          12 :                         return makeBoolConst(false, false);
    2732             : 
    2733             :                     /* one null? then distinct */
    2734          42 :                     if (has_null_input)
    2735          18 :                         return makeBoolConst(true, false);
    2736             : 
    2737             :                     /* otherwise try to evaluate the '=' operator */
    2738             :                     /* (NOT okay to try to inline it, though!) */
    2739             : 
    2740             :                     /*
    2741             :                      * Need to get OID of underlying function.  Okay to
    2742             :                      * scribble on input to this extent.
    2743             :                      */
    2744          24 :                     set_opfuncid((OpExpr *) expr);  /* rely on struct
    2745             :                                                      * equivalence */
    2746             : 
    2747             :                     /*
    2748             :                      * Code for op/func reduction is pretty bulky, so split it
    2749             :                      * out as a separate function.
    2750             :                      */
    2751          24 :                     simple = simplify_function(expr->opfuncid,
    2752             :                                                expr->opresulttype, -1,
    2753             :                                                expr->opcollid,
    2754             :                                                expr->inputcollid,
    2755             :                                                &args,
    2756             :                                                false,
    2757             :                                                false,
    2758             :                                                false,
    2759             :                                                context);
    2760          24 :                     if (simple) /* successfully simplified it */
    2761             :                     {
    2762             :                         /*
    2763             :                          * Since the underlying operator is "=", must negate
    2764             :                          * its result
    2765             :                          */
    2766          24 :                         Const      *csimple = castNode(Const, simple);
    2767             : 
    2768          24 :                         csimple->constvalue =
    2769          24 :                             BoolGetDatum(!DatumGetBool(csimple->constvalue));
    2770          24 :                         return (Node *) csimple;
    2771             :                     }
    2772             :                 }
    2773             : 
    2774             :                 /*
    2775             :                  * The expression cannot be simplified any further, so build
    2776             :                  * and return a replacement DistinctExpr node using the
    2777             :                  * possibly-simplified arguments.
    2778             :                  */
    2779        1150 :                 newexpr = makeNode(DistinctExpr);
    2780        1150 :                 newexpr->opno = expr->opno;
    2781        1150 :                 newexpr->opfuncid = expr->opfuncid;
    2782        1150 :                 newexpr->opresulttype = expr->opresulttype;
    2783        1150 :                 newexpr->opretset = expr->opretset;
    2784        1150 :                 newexpr->opcollid = expr->opcollid;
    2785        1150 :                 newexpr->inputcollid = expr->inputcollid;
    2786        1150 :                 newexpr->args = args;
    2787        1150 :                 newexpr->location = expr->location;
    2788        1150 :                 return (Node *) newexpr;
    2789             :             }
    2790         740 :         case T_NullIfExpr:
    2791             :             {
    2792             :                 NullIfExpr *expr;
    2793             :                 ListCell   *arg;
    2794         740 :                 bool        has_nonconst_input = false;
    2795             : 
    2796             :                 /* Copy the node and const-simplify its arguments */
    2797         740 :                 expr = (NullIfExpr *) ece_generic_processing(node);
    2798             : 
    2799             :                 /* If either argument is NULL they can't be equal */
    2800        2214 :                 foreach(arg, expr->args)
    2801             :                 {
    2802        1480 :                     if (!IsA(lfirst(arg), Const))
    2803         708 :                         has_nonconst_input = true;
    2804         772 :                     else if (((Const *) lfirst(arg))->constisnull)
    2805           6 :                         return (Node *) linitial(expr->args);
    2806             :                 }
    2807             : 
    2808             :                 /*
    2809             :                  * Need to get OID of underlying function before checking if
    2810             :                  * the function is OK to evaluate.
    2811             :                  */
    2812         734 :                 set_opfuncid((OpExpr *) expr);
    2813             : 
    2814         772 :                 if (!has_nonconst_input &&
    2815          38 :                     ece_function_is_safe(expr->opfuncid, context))
    2816          38 :                     return ece_evaluate_expr(expr);
    2817             : 
    2818         696 :                 return (Node *) expr;
    2819             :             }
    2820       37656 :         case T_ScalarArrayOpExpr:
    2821             :             {
    2822             :                 ScalarArrayOpExpr *saop;
    2823             : 
    2824             :                 /* Copy the node and const-simplify its arguments */
    2825       37656 :                 saop = (ScalarArrayOpExpr *) ece_generic_processing(node);
    2826             : 
    2827             :                 /* Make sure we know underlying function */
    2828       37656 :                 set_sa_opfuncid(saop);
    2829             : 
    2830             :                 /*
    2831             :                  * If all arguments are Consts, and it's a safe function, we
    2832             :                  * can fold to a constant
    2833             :                  */
    2834       37994 :                 if (ece_all_arguments_const(saop) &&
    2835         338 :                     ece_function_is_safe(saop->opfuncid, context))
    2836         338 :                     return ece_evaluate_expr(saop);
    2837       37318 :                 return (Node *) saop;
    2838             :             }
    2839      168796 :         case T_BoolExpr:
    2840             :             {
    2841      168796 :                 BoolExpr   *expr = (BoolExpr *) node;
    2842             : 
    2843      168796 :                 switch (expr->boolop)
    2844             :                 {
    2845       12480 :                     case OR_EXPR:
    2846             :                         {
    2847             :                             List       *newargs;
    2848       12480 :                             bool        haveNull = false;
    2849       12480 :                             bool        forceTrue = false;
    2850             : 
    2851       12480 :                             newargs = simplify_or_arguments(expr->args,
    2852             :                                                             context,
    2853             :                                                             &haveNull,
    2854             :                                                             &forceTrue);
    2855       12480 :                             if (forceTrue)
    2856         168 :                                 return makeBoolConst(true, false);
    2857       12312 :                             if (haveNull)
    2858          30 :                                 newargs = lappend(newargs,
    2859          30 :                                                   makeBoolConst(false, true));
    2860             :                             /* If all the inputs are FALSE, result is FALSE */
    2861       12312 :                             if (newargs == NIL)
    2862          34 :                                 return makeBoolConst(false, false);
    2863             : 
    2864             :                             /*
    2865             :                              * If only one nonconst-or-NULL input, it's the
    2866             :                              * result
    2867             :                              */
    2868       12278 :                             if (list_length(newargs) == 1)
    2869         138 :                                 return (Node *) linitial(newargs);
    2870             :                             /* Else we still need an OR node */
    2871       12140 :                             return (Node *) make_orclause(newargs);
    2872             :                         }
    2873      141754 :                     case AND_EXPR:
    2874             :                         {
    2875             :                             List       *newargs;
    2876      141754 :                             bool        haveNull = false;
    2877      141754 :                             bool        forceFalse = false;
    2878             : 
    2879      141754 :                             newargs = simplify_and_arguments(expr->args,
    2880             :                                                              context,
    2881             :                                                              &haveNull,
    2882             :                                                              &forceFalse);
    2883      141754 :                             if (forceFalse)
    2884        1554 :                                 return makeBoolConst(false, false);
    2885      140200 :                             if (haveNull)
    2886           6 :                                 newargs = lappend(newargs,
    2887           6 :                                                   makeBoolConst(false, true));
    2888             :                             /* If all the inputs are TRUE, result is TRUE */
    2889      140200 :                             if (newargs == NIL)
    2890         368 :                                 return makeBoolConst(true, false);
    2891             : 
    2892             :                             /*
    2893             :                              * If only one nonconst-or-NULL input, it's the
    2894             :                              * result
    2895             :                              */
    2896      139832 :                             if (list_length(newargs) == 1)
    2897         148 :                                 return (Node *) linitial(newargs);
    2898             :                             /* Else we still need an AND node */
    2899      139684 :                             return (Node *) make_andclause(newargs);
    2900             :                         }
    2901       14562 :                     case NOT_EXPR:
    2902             :                         {
    2903             :                             Node       *arg;
    2904             : 
    2905             :                             Assert(list_length(expr->args) == 1);
    2906       14562 :                             arg = eval_const_expressions_mutator(linitial(expr->args),
    2907             :                                                                  context);
    2908             : 
    2909             :                             /*
    2910             :                              * Use negate_clause() to see if we can simplify
    2911             :                              * away the NOT.
    2912             :                              */
    2913       14562 :                             return negate_clause(arg);
    2914             :                         }
    2915           0 :                     default:
    2916           0 :                         elog(ERROR, "unrecognized boolop: %d",
    2917             :                              (int) expr->boolop);
    2918             :                         break;
    2919             :                 }
    2920             :                 break;
    2921             :             }
    2922             : 
    2923         750 :         case T_JsonValueExpr:
    2924             :             {
    2925         750 :                 JsonValueExpr *jve = (JsonValueExpr *) node;
    2926         750 :                 Node       *raw_expr = (Node *) jve->raw_expr;
    2927         750 :                 Node       *formatted_expr = (Node *) jve->formatted_expr;
    2928             : 
    2929             :                 /*
    2930             :                  * If we can fold formatted_expr to a constant, we can elide
    2931             :                  * the JsonValueExpr altogether.  Otherwise we must process
    2932             :                  * raw_expr too.  But JsonFormat is a flat node and requires
    2933             :                  * no simplification, only copying.
    2934             :                  */
    2935         750 :                 formatted_expr = eval_const_expressions_mutator(formatted_expr,
    2936             :                                                                 context);
    2937         750 :                 if (formatted_expr && IsA(formatted_expr, Const))
    2938         522 :                     return formatted_expr;
    2939             : 
    2940         228 :                 raw_expr = eval_const_expressions_mutator(raw_expr, context);
    2941             : 
    2942         228 :                 return (Node *) makeJsonValueExpr((Expr *) raw_expr,
    2943             :                                                   (Expr *) formatted_expr,
    2944         228 :                                                   copyObject(jve->format));
    2945             :             }
    2946             : 
    2947         582 :         case T_SubPlan:
    2948             :         case T_AlternativeSubPlan:
    2949             : 
    2950             :             /*
    2951             :              * Return a SubPlan unchanged --- too late to do anything with it.
    2952             :              *
    2953             :              * XXX should we ereport() here instead?  Probably this routine
    2954             :              * should never be invoked after SubPlan creation.
    2955             :              */
    2956         582 :             return node;
    2957      171976 :         case T_RelabelType:
    2958             :             {
    2959      171976 :                 RelabelType *relabel = (RelabelType *) node;
    2960             :                 Node       *arg;
    2961             : 
    2962             :                 /* Simplify the input ... */
    2963      171976 :                 arg = eval_const_expressions_mutator((Node *) relabel->arg,
    2964             :                                                      context);
    2965             :                 /* ... and attach a new RelabelType node, if needed */
    2966      171970 :                 return applyRelabelType(arg,
    2967             :                                         relabel->resulttype,
    2968             :                                         relabel->resulttypmod,
    2969             :                                         relabel->resultcollid,
    2970             :                                         relabel->relabelformat,
    2971             :                                         relabel->location,
    2972             :                                         true);
    2973             :             }
    2974       25514 :         case T_CoerceViaIO:
    2975             :             {
    2976       25514 :                 CoerceViaIO *expr = (CoerceViaIO *) node;
    2977             :                 List       *args;
    2978             :                 Oid         outfunc;
    2979             :                 bool        outtypisvarlena;
    2980             :                 Oid         infunc;
    2981             :                 Oid         intypioparam;
    2982             :                 Expr       *simple;
    2983             :                 CoerceViaIO *newexpr;
    2984             : 
    2985             :                 /* Make a List so we can use simplify_function */
    2986       25514 :                 args = list_make1(expr->arg);
    2987             : 
    2988             :                 /*
    2989             :                  * CoerceViaIO represents calling the source type's output
    2990             :                  * function then the result type's input function.  So, try to
    2991             :                  * simplify it as though it were a stack of two such function
    2992             :                  * calls.  First we need to know what the functions are.
    2993             :                  *
    2994             :                  * Note that the coercion functions are assumed not to care
    2995             :                  * about input collation, so we just pass InvalidOid for that.
    2996             :                  */
    2997       25514 :                 getTypeOutputInfo(exprType((Node *) expr->arg),
    2998             :                                   &outfunc, &outtypisvarlena);
    2999       25514 :                 getTypeInputInfo(expr->resulttype,
    3000             :                                  &infunc, &intypioparam);
    3001             : 
    3002       25514 :                 simple = simplify_function(outfunc,
    3003             :                                            CSTRINGOID, -1,
    3004             :                                            InvalidOid,
    3005             :                                            InvalidOid,
    3006             :                                            &args,
    3007             :                                            false,
    3008             :                                            true,
    3009             :                                            true,
    3010             :                                            context);
    3011       25514 :                 if (simple)     /* successfully simplified output fn */
    3012             :                 {
    3013             :                     /*
    3014             :                      * Input functions may want 1 to 3 arguments.  We always
    3015             :                      * supply all three, trusting that nothing downstream will
    3016             :                      * complain.
    3017             :                      */
    3018        2336 :                     args = list_make3(simple,
    3019             :                                       makeConst(OIDOID,
    3020             :                                                 -1,
    3021             :                                                 InvalidOid,
    3022             :                                                 sizeof(Oid),
    3023             :                                                 ObjectIdGetDatum(intypioparam),
    3024             :                                                 false,
    3025             :                                                 true),
    3026             :                                       makeConst(INT4OID,
    3027             :                                                 -1,
    3028             :                                                 InvalidOid,
    3029             :                                                 sizeof(int32),
    3030             :                                                 Int32GetDatum(-1),
    3031             :                                                 false,
    3032             :                                                 true));
    3033             : 
    3034        2336 :                     simple = simplify_function(infunc,
    3035             :                                                expr->resulttype, -1,
    3036             :                                                expr->resultcollid,
    3037             :                                                InvalidOid,
    3038             :                                                &args,
    3039             :                                                false,
    3040             :                                                false,
    3041             :                                                true,
    3042             :                                                context);
    3043        2284 :                     if (simple) /* successfully simplified input fn */
    3044        2204 :                         return (Node *) simple;
    3045             :                 }
    3046             : 
    3047             :                 /*
    3048             :                  * The expression cannot be simplified any further, so build
    3049             :                  * and return a replacement CoerceViaIO node using the
    3050             :                  * possibly-simplified argument.
    3051             :                  */
    3052       23258 :                 newexpr = makeNode(CoerceViaIO);
    3053       23258 :                 newexpr->arg = (Expr *) linitial(args);
    3054       23258 :                 newexpr->resulttype = expr->resulttype;
    3055       23258 :                 newexpr->resultcollid = expr->resultcollid;
    3056       23258 :                 newexpr->coerceformat = expr->coerceformat;
    3057       23258 :                 newexpr->location = expr->location;
    3058       23258 :                 return (Node *) newexpr;
    3059             :             }
    3060        9978 :         case T_ArrayCoerceExpr:
    3061             :             {
    3062        9978 :                 ArrayCoerceExpr *ac = makeNode(ArrayCoerceExpr);
    3063             :                 Node       *save_case_val;
    3064             : 
    3065             :                 /*
    3066             :                  * Copy the node and const-simplify its arguments.  We can't
    3067             :                  * use ece_generic_processing() here because we need to mess
    3068             :                  * with case_val only while processing the elemexpr.
    3069             :                  */
    3070        9978 :                 memcpy(ac, node, sizeof(ArrayCoerceExpr));
    3071        9978 :                 ac->arg = (Expr *)
    3072        9978 :                     eval_const_expressions_mutator((Node *) ac->arg,
    3073             :                                                    context);
    3074             : 
    3075             :                 /*
    3076             :                  * Set up for the CaseTestExpr node contained in the elemexpr.
    3077             :                  * We must prevent it from absorbing any outer CASE value.
    3078             :                  */
    3079        9978 :                 save_case_val = context->case_val;
    3080        9978 :                 context->case_val = NULL;
    3081             : 
    3082        9978 :                 ac->elemexpr = (Expr *)
    3083        9978 :                     eval_const_expressions_mutator((Node *) ac->elemexpr,
    3084             :                                                    context);
    3085             : 
    3086        9978 :                 context->case_val = save_case_val;
    3087             : 
    3088             :                 /*
    3089             :                  * If constant argument and the per-element expression is
    3090             :                  * immutable, we can simplify the whole thing to a constant.
    3091             :                  * Exception: although contain_mutable_functions considers
    3092             :                  * CoerceToDomain immutable for historical reasons, let's not
    3093             :                  * do so here; this ensures coercion to an array-over-domain
    3094             :                  * does not apply the domain's constraints until runtime.
    3095             :                  */
    3096        9978 :                 if (ac->arg && IsA(ac->arg, Const) &&
    3097        1118 :                     ac->elemexpr && !IsA(ac->elemexpr, CoerceToDomain) &&
    3098        1094 :                     !contain_mutable_functions((Node *) ac->elemexpr))
    3099        1094 :                     return ece_evaluate_expr(ac);
    3100             : 
    3101        8884 :                 return (Node *) ac;
    3102             :             }
    3103        8978 :         case T_CollateExpr:
    3104             :             {
    3105             :                 /*
    3106             :                  * We replace CollateExpr with RelabelType, so as to improve
    3107             :                  * uniformity of expression representation and thus simplify
    3108             :                  * comparison of expressions.  Hence this looks very nearly
    3109             :                  * the same as the RelabelType case, and we can apply the same
    3110             :                  * optimizations to avoid unnecessary RelabelTypes.
    3111             :                  */
    3112        8978 :                 CollateExpr *collate = (CollateExpr *) node;
    3113             :                 Node       *arg;
    3114             : 
    3115             :                 /* Simplify the input ... */
    3116        8978 :                 arg = eval_const_expressions_mutator((Node *) collate->arg,
    3117             :                                                      context);
    3118             :                 /* ... and attach a new RelabelType node, if needed */
    3119        8978 :                 return applyRelabelType(arg,
    3120             :                                         exprType(arg),
    3121             :                                         exprTypmod(arg),
    3122             :                                         collate->collOid,
    3123             :                                         COERCE_IMPLICIT_CAST,
    3124             :                                         collate->location,
    3125             :                                         true);
    3126             :             }
    3127       33160 :         case T_CaseExpr:
    3128             :             {
    3129             :                 /*----------
    3130             :                  * CASE expressions can be simplified if there are constant
    3131             :                  * condition clauses:
    3132             :                  *      FALSE (or NULL): drop the alternative
    3133             :                  *      TRUE: drop all remaining alternatives
    3134             :                  * If the first non-FALSE alternative is a constant TRUE,
    3135             :                  * we can simplify the entire CASE to that alternative's
    3136             :                  * expression.  If there are no non-FALSE alternatives,
    3137             :                  * we simplify the entire CASE to the default result (ELSE).
    3138             :                  *
    3139             :                  * If we have a simple-form CASE with constant test
    3140             :                  * expression, we substitute the constant value for contained
    3141             :                  * CaseTestExpr placeholder nodes, so that we have the
    3142             :                  * opportunity to reduce constant test conditions.  For
    3143             :                  * example this allows
    3144             :                  *      CASE 0 WHEN 0 THEN 1 ELSE 1/0 END
    3145             :                  * to reduce to 1 rather than drawing a divide-by-0 error.
    3146             :                  * Note that when the test expression is constant, we don't
    3147             :                  * have to include it in the resulting CASE; for example
    3148             :                  *      CASE 0 WHEN x THEN y ELSE z END
    3149             :                  * is transformed by the parser to
    3150             :                  *      CASE 0 WHEN CaseTestExpr = x THEN y ELSE z END
    3151             :                  * which we can simplify to
    3152             :                  *      CASE WHEN 0 = x THEN y ELSE z END
    3153             :                  * It is not necessary for the executor to evaluate the "arg"
    3154             :                  * expression when executing the CASE, since any contained
    3155             :                  * CaseTestExprs that might have referred to it will have been
    3156             :                  * replaced by the constant.
    3157             :                  *----------
    3158             :                  */
    3159       33160 :                 CaseExpr   *caseexpr = (CaseExpr *) node;
    3160             :                 CaseExpr   *newcase;
    3161             :                 Node       *save_case_val;
    3162             :                 Node       *newarg;
    3163             :                 List       *newargs;
    3164             :                 bool        const_true_cond;
    3165       33160 :                 Node       *defresult = NULL;
    3166             :                 ListCell   *arg;
    3167             : 
    3168             :                 /* Simplify the test expression, if any */
    3169       33160 :                 newarg = eval_const_expressions_mutator((Node *) caseexpr->arg,
    3170             :                                                         context);
    3171             : 
    3172             :                 /* Set up for contained CaseTestExpr nodes */
    3173       33160 :                 save_case_val = context->case_val;
    3174       33160 :                 if (newarg && IsA(newarg, Const))
    3175             :                 {
    3176          78 :                     context->case_val = newarg;
    3177          78 :                     newarg = NULL;  /* not needed anymore, see above */
    3178             :                 }
    3179             :                 else
    3180       33082 :                     context->case_val = NULL;
    3181             : 
    3182             :                 /* Simplify the WHEN clauses */
    3183       33160 :                 newargs = NIL;
    3184       33160 :                 const_true_cond = false;
    3185       94724 :                 foreach(arg, caseexpr->args)
    3186             :                 {
    3187       62286 :                     CaseWhen   *oldcasewhen = lfirst_node(CaseWhen, arg);
    3188             :                     Node       *casecond;
    3189             :                     Node       *caseresult;
    3190             : 
    3191             :                     /* Simplify this alternative's test condition */
    3192       62286 :                     casecond = eval_const_expressions_mutator((Node *) oldcasewhen->expr,
    3193             :                                                               context);
    3194             : 
    3195             :                     /*
    3196             :                      * If the test condition is constant FALSE (or NULL), then
    3197             :                      * drop this WHEN clause completely, without processing
    3198             :                      * the result.
    3199             :                      */
    3200       62286 :                     if (casecond && IsA(casecond, Const))
    3201             :                     {
    3202        1922 :                         Const      *const_input = (Const *) casecond;
    3203             : 
    3204        1922 :                         if (const_input->constisnull ||
    3205        1922 :                             !DatumGetBool(const_input->constvalue))
    3206        1206 :                             continue;   /* drop alternative with FALSE cond */
    3207             :                         /* Else it's constant TRUE */
    3208         716 :                         const_true_cond = true;
    3209             :                     }
    3210             : 
    3211             :                     /* Simplify this alternative's result value */
    3212       61080 :                     caseresult = eval_const_expressions_mutator((Node *) oldcasewhen->result,
    3213             :                                                                 context);
    3214             : 
    3215             :                     /* If non-constant test condition, emit a new WHEN node */
    3216       61074 :                     if (!const_true_cond)
    3217       60358 :                     {
    3218       60358 :                         CaseWhen   *newcasewhen = makeNode(CaseWhen);
    3219             : 
    3220       60358 :                         newcasewhen->expr = (Expr *) casecond;
    3221       60358 :                         newcasewhen->result = (Expr *) caseresult;
    3222       60358 :                         newcasewhen->location = oldcasewhen->location;
    3223       60358 :                         newargs = lappend(newargs, newcasewhen);
    3224       60358 :                         continue;
    3225             :                     }
    3226             : 
    3227             :                     /*
    3228             :                      * Found a TRUE condition, so none of the remaining
    3229             :                      * alternatives can be reached.  We treat the result as
    3230             :                      * the default result.
    3231             :                      */
    3232         716 :                     defresult = caseresult;
    3233         716 :                     break;
    3234             :                 }
    3235             : 
    3236             :                 /* Simplify the default result, unless we replaced it above */
    3237       33154 :                 if (!const_true_cond)
    3238       32438 :                     defresult = eval_const_expressions_mutator((Node *) caseexpr->defresult,
    3239             :                                                                context);
    3240             : 
    3241       33154 :                 context->case_val = save_case_val;
    3242             : 
    3243             :                 /*
    3244             :                  * If no non-FALSE alternatives, CASE reduces to the default
    3245             :                  * result
    3246             :                  */
    3247       33154 :                 if (newargs == NIL)
    3248        1148 :                     return defresult;
    3249             :                 /* Otherwise we need a new CASE node */
    3250       32006 :                 newcase = makeNode(CaseExpr);
    3251       32006 :                 newcase->casetype = caseexpr->casetype;
    3252       32006 :                 newcase->casecollid = caseexpr->casecollid;
    3253       32006 :                 newcase->arg = (Expr *) newarg;
    3254       32006 :                 newcase->args = newargs;
    3255       32006 :                 newcase->defresult = (Expr *) defresult;
    3256       32006 :                 newcase->location = caseexpr->location;
    3257       32006 :                 return (Node *) newcase;
    3258             :             }
    3259       32490 :         case T_CaseTestExpr:
    3260             :             {
    3261             :                 /*
    3262             :                  * If we know a constant test value for the current CASE
    3263             :                  * construct, substitute it for the placeholder.  Else just
    3264             :                  * return the placeholder as-is.
    3265             :                  */
    3266       32490 :                 if (context->case_val)
    3267         144 :                     return copyObject(context->case_val);
    3268             :                 else
    3269       32346 :                     return copyObject(node);
    3270             :             }
    3271       59726 :         case T_SubscriptingRef:
    3272             :         case T_ArrayExpr:
    3273             :         case T_RowExpr:
    3274             :         case T_MinMaxExpr:
    3275             :             {
    3276             :                 /*
    3277             :                  * Generic handling for node types whose own processing is
    3278             :                  * known to be immutable, and for which we need no smarts
    3279             :                  * beyond "simplify if all inputs are constants".
    3280             :                  *
    3281             :                  * Treating SubscriptingRef this way assumes that subscripting
    3282             :                  * fetch and assignment are both immutable.  This constrains
    3283             :                  * type-specific subscripting implementations; maybe we should
    3284             :                  * relax it someday.
    3285             :                  *
    3286             :                  * Treating MinMaxExpr this way amounts to assuming that the
    3287             :                  * btree comparison function it calls is immutable; see the
    3288             :                  * reasoning in contain_mutable_functions_walker.
    3289             :                  */
    3290             : 
    3291             :                 /* Copy the node and const-simplify its arguments */
    3292       59726 :                 node = ece_generic_processing(node);
    3293             :                 /* If all arguments are Consts, we can fold to a constant */
    3294       59726 :                 if (ece_all_arguments_const(node))
    3295       29906 :                     return ece_evaluate_expr(node);
    3296       29820 :                 return node;
    3297             :             }
    3298        2634 :         case T_CoalesceExpr:
    3299             :             {
    3300        2634 :                 CoalesceExpr *coalesceexpr = (CoalesceExpr *) node;
    3301             :                 CoalesceExpr *newcoalesce;
    3302             :                 List       *newargs;
    3303             :                 ListCell   *arg;
    3304             : 
    3305        2634 :                 newargs = NIL;
    3306        6342 :                 foreach(arg, coalesceexpr->args)
    3307             :                 {
    3308             :                     Node       *e;
    3309             : 
    3310        5208 :                     e = eval_const_expressions_mutator((Node *) lfirst(arg),
    3311             :                                                        context);
    3312             : 
    3313             :                     /*
    3314             :                      * We can remove null constants from the list. For a
    3315             :                      * non-null constant, if it has not been preceded by any
    3316             :                      * other non-null-constant expressions then it is the
    3317             :                      * result. Otherwise, it's the next argument, but we can
    3318             :                      * drop following arguments since they will never be
    3319             :                      * reached.
    3320             :                      */
    3321        5208 :                     if (IsA(e, Const))
    3322             :                     {
    3323        1544 :                         if (((Const *) e)->constisnull)
    3324          44 :                             continue;   /* drop null constant */
    3325        1500 :                         if (newargs == NIL)
    3326          98 :                             return e;   /* first expr */
    3327        1402 :                         newargs = lappend(newargs, e);
    3328        1402 :                         break;
    3329             :                     }
    3330        3664 :                     newargs = lappend(newargs, e);
    3331             :                 }
    3332             : 
    3333             :                 /*
    3334             :                  * If all the arguments were constant null, the result is just
    3335             :                  * null
    3336             :                  */
    3337        2536 :                 if (newargs == NIL)
    3338           0 :                     return (Node *) makeNullConst(coalesceexpr->coalescetype,
    3339             :                                                   -1,
    3340             :                                                   coalesceexpr->coalescecollid);
    3341             : 
    3342             :                 /*
    3343             :                  * If there's exactly one surviving argument, we no longer
    3344             :                  * need COALESCE at all: the result is that argument
    3345             :                  */
    3346        2536 :                 if (list_length(newargs) == 1)
    3347          18 :                     return (Node *) linitial(newargs);
    3348             : 
    3349        2518 :                 newcoalesce = makeNode(CoalesceExpr);
    3350        2518 :                 newcoalesce->coalescetype = coalesceexpr->coalescetype;
    3351        2518 :                 newcoalesce->coalescecollid = coalesceexpr->coalescecollid;
    3352        2518 :                 newcoalesce->args = newargs;
    3353        2518 :                 newcoalesce->location = coalesceexpr->location;
    3354        2518 :                 return (Node *) newcoalesce;
    3355             :             }
    3356        4940 :         case T_SQLValueFunction:
    3357             :             {
    3358             :                 /*
    3359             :                  * All variants of SQLValueFunction are stable, so if we are
    3360             :                  * estimating the expression's value, we should evaluate the
    3361             :                  * current function value.  Otherwise just copy.
    3362             :                  */
    3363        4940 :                 SQLValueFunction *svf = (SQLValueFunction *) node;
    3364             : 
    3365        4940 :                 if (context->estimate)
    3366         846 :                     return (Node *) evaluate_expr((Expr *) svf,
    3367             :                                                   svf->type,
    3368             :                                                   svf->typmod,
    3369             :                                                   InvalidOid);
    3370             :                 else
    3371        4094 :                     return copyObject((Node *) svf);
    3372             :             }
    3373        5556 :         case T_FieldSelect:
    3374             :             {
    3375             :                 /*
    3376             :                  * We can optimize field selection from a whole-row Var into a
    3377             :                  * simple Var.  (This case won't be generated directly by the
    3378             :                  * parser, because ParseComplexProjection short-circuits it.
    3379             :                  * But it can arise while simplifying functions.)  Also, we
    3380             :                  * can optimize field selection from a RowExpr construct, or
    3381             :                  * of course from a constant.
    3382             :                  *
    3383             :                  * However, replacing a whole-row Var in this way has a
    3384             :                  * pitfall: if we've already built the rel targetlist for the
    3385             :                  * source relation, then the whole-row Var is scheduled to be
    3386             :                  * produced by the relation scan, but the simple Var probably
    3387             :                  * isn't, which will lead to a failure in setrefs.c.  This is
    3388             :                  * not a problem when handling simple single-level queries, in
    3389             :                  * which expression simplification always happens first.  It
    3390             :                  * is a risk for lateral references from subqueries, though.
    3391             :                  * To avoid such failures, don't optimize uplevel references.
    3392             :                  *
    3393             :                  * We must also check that the declared type of the field is
    3394             :                  * still the same as when the FieldSelect was created --- this
    3395             :                  * can change if someone did ALTER COLUMN TYPE on the rowtype.
    3396             :                  * If it isn't, we skip the optimization; the case will
    3397             :                  * probably fail at runtime, but that's not our problem here.
    3398             :                  */
    3399        5556 :                 FieldSelect *fselect = (FieldSelect *) node;
    3400             :                 FieldSelect *newfselect;
    3401             :                 Node       *arg;
    3402             : 
    3403        5556 :                 arg = eval_const_expressions_mutator((Node *) fselect->arg,
    3404             :                                                      context);
    3405        5556 :                 if (arg && IsA(arg, Var) &&
    3406        1560 :                     ((Var *) arg)->varattno == InvalidAttrNumber &&
    3407          90 :                     ((Var *) arg)->varlevelsup == 0)
    3408             :                 {
    3409          78 :                     if (rowtype_field_matches(((Var *) arg)->vartype,
    3410          78 :                                               fselect->fieldnum,
    3411             :                                               fselect->resulttype,
    3412             :                                               fselect->resulttypmod,
    3413             :                                               fselect->resultcollid))
    3414             :                     {
    3415             :                         Var        *newvar;
    3416             : 
    3417          78 :                         newvar = makeVar(((Var *) arg)->varno,
    3418          78 :                                          fselect->fieldnum,
    3419             :                                          fselect->resulttype,
    3420             :                                          fselect->resulttypmod,
    3421             :                                          fselect->resultcollid,
    3422             :                                          ((Var *) arg)->varlevelsup);
    3423             :                         /* New Var has same OLD/NEW returning as old one */
    3424          78 :                         newvar->varreturningtype = ((Var *) arg)->varreturningtype;
    3425             :                         /* New Var is nullable by same rels as the old one */
    3426          78 :                         newvar->varnullingrels = ((Var *) arg)->varnullingrels;
    3427          78 :                         return (Node *) newvar;
    3428             :                     }
    3429             :                 }
    3430        5478 :                 if (arg && IsA(arg, RowExpr))
    3431             :                 {
    3432          24 :                     RowExpr    *rowexpr = (RowExpr *) arg;
    3433             : 
    3434          48 :                     if (fselect->fieldnum > 0 &&
    3435          24 :                         fselect->fieldnum <= list_length(rowexpr->args))
    3436             :                     {
    3437          24 :                         Node       *fld = (Node *) list_nth(rowexpr->args,
    3438          24 :                                                             fselect->fieldnum - 1);
    3439             : 
    3440          24 :                         if (rowtype_field_matches(rowexpr->row_typeid,
    3441          24 :                                                   fselect->fieldnum,
    3442             :                                                   fselect->resulttype,
    3443             :                                                   fselect->resulttypmod,
    3444          24 :                                                   fselect->resultcollid) &&
    3445          48 :                             fselect->resulttype == exprType(fld) &&
    3446          48 :                             fselect->resulttypmod == exprTypmod(fld) &&
    3447          24 :                             fselect->resultcollid == exprCollation(fld))
    3448          24 :                             return fld;
    3449             :                     }
    3450             :                 }
    3451        5454 :                 newfselect = makeNode(FieldSelect);
    3452        5454 :                 newfselect->arg = (Expr *) arg;
    3453        5454 :                 newfselect->fieldnum = fselect->fieldnum;
    3454        5454 :                 newfselect->resulttype = fselect->resulttype;
    3455        5454 :                 newfselect->resulttypmod = fselect->resulttypmod;
    3456        5454 :                 newfselect->resultcollid = fselect->resultcollid;
    3457        5454 :                 if (arg && IsA(arg, Const))
    3458             :                 {
    3459         604 :                     Const      *con = (Const *) arg;
    3460             : 
    3461         604 :                     if (rowtype_field_matches(con->consttype,
    3462         604 :                                               newfselect->fieldnum,
    3463             :                                               newfselect->resulttype,
    3464             :                                               newfselect->resulttypmod,
    3465             :                                               newfselect->resultcollid))
    3466         604 :                         return ece_evaluate_expr(newfselect);
    3467             :                 }
    3468        4850 :                 return (Node *) newfselect;
    3469             :             }
    3470       35314 :         case T_NullTest:
    3471             :             {
    3472       35314 :                 NullTest   *ntest = (NullTest *) node;
    3473             :                 NullTest   *newntest;
    3474             :                 Node       *arg;
    3475             : 
    3476       35314 :                 arg = eval_const_expressions_mutator((Node *) ntest->arg,
    3477             :                                                      context);
    3478       35312 :                 if (ntest->argisrow && arg && IsA(arg, RowExpr))
    3479             :                 {
    3480             :                     /*
    3481             :                      * We break ROW(...) IS [NOT] NULL into separate tests on
    3482             :                      * its component fields.  This form is usually more
    3483             :                      * efficient to evaluate, as well as being more amenable
    3484             :                      * to optimization.
    3485             :                      */
    3486          48 :                     RowExpr    *rarg = (RowExpr *) arg;
    3487          48 :                     List       *newargs = NIL;
    3488             :                     ListCell   *l;
    3489             : 
    3490         174 :                     foreach(l, rarg->args)
    3491             :                     {
    3492         126 :                         Node       *relem = (Node *) lfirst(l);
    3493             : 
    3494             :                         /*
    3495             :                          * A constant field refutes the whole NullTest if it's
    3496             :                          * of the wrong nullness; else we can discard it.
    3497             :                          */
    3498         126 :                         if (relem && IsA(relem, Const))
    3499           0 :                         {
    3500           0 :                             Const      *carg = (Const *) relem;
    3501             : 
    3502           0 :                             if (carg->constisnull ?
    3503           0 :                                 (ntest->nulltesttype == IS_NOT_NULL) :
    3504           0 :                                 (ntest->nulltesttype == IS_NULL))
    3505           0 :                                 return makeBoolConst(false, false);
    3506           0 :                             continue;
    3507             :                         }
    3508             : 
    3509             :                         /*
    3510             :                          * Else, make a scalar (argisrow == false) NullTest
    3511             :                          * for this field.  Scalar semantics are required
    3512             :                          * because IS [NOT] NULL doesn't recurse; see comments
    3513             :                          * in ExecEvalRowNullInt().
    3514             :                          */
    3515         126 :                         newntest = makeNode(NullTest);
    3516         126 :                         newntest->arg = (Expr *) relem;
    3517         126 :                         newntest->nulltesttype = ntest->nulltesttype;
    3518         126 :                         newntest->argisrow = false;
    3519         126 :                         newntest->location = ntest->location;
    3520         126 :                         newargs = lappend(newargs, newntest);
    3521             :                     }
    3522             :                     /* If all the inputs were constants, result is TRUE */
    3523          48 :                     if (newargs == NIL)
    3524           0 :                         return makeBoolConst(true, false);
    3525             :                     /* If only one nonconst input, it's the result */
    3526          48 :                     if (list_length(newargs) == 1)
    3527           0 :                         return (Node *) linitial(newargs);
    3528             :                     /* Else we need an AND node */
    3529          48 :                     return (Node *) make_andclause(newargs);
    3530             :                 }
    3531       35264 :                 if (!ntest->argisrow && arg && IsA(arg, Const))
    3532             :                 {
    3533         390 :                     Const      *carg = (Const *) arg;
    3534             :                     bool        result;
    3535             : 
    3536         390 :                     switch (ntest->nulltesttype)
    3537             :                     {
    3538         326 :                         case IS_NULL:
    3539         326 :                             result = carg->constisnull;
    3540         326 :                             break;
    3541          64 :                         case IS_NOT_NULL:
    3542          64 :                             result = !carg->constisnull;
    3543          64 :                             break;
    3544           0 :                         default:
    3545           0 :                             elog(ERROR, "unrecognized nulltesttype: %d",
    3546             :                                  (int) ntest->nulltesttype);
    3547             :                             result = false; /* keep compiler quiet */
    3548             :                             break;
    3549             :                     }
    3550             : 
    3551         390 :                     return makeBoolConst(result, false);
    3552             :                 }
    3553       34874 :                 if (!ntest->argisrow && arg && IsA(arg, Var) && context->root)
    3554             :                 {
    3555       16384 :                     Var        *varg = (Var *) arg;
    3556             :                     bool        result;
    3557             : 
    3558       16384 :                     if (var_is_nonnullable(context->root, varg, false))
    3559             :                     {
    3560         462 :                         switch (ntest->nulltesttype)
    3561             :                         {
    3562         112 :                             case IS_NULL:
    3563         112 :                                 result = false;
    3564         112 :                                 break;
    3565         350 :                             case IS_NOT_NULL:
    3566         350 :                                 result = true;
    3567         350 :                                 break;
    3568           0 :                             default:
    3569           0 :                                 elog(ERROR, "unrecognized nulltesttype: %d",
    3570             :                                      (int) ntest->nulltesttype);
    3571             :                                 result = false; /* keep compiler quiet */
    3572             :                                 break;
    3573             :                         }
    3574             : 
    3575         462 :                         return makeBoolConst(result, false);
    3576             :                     }
    3577             :                 }
    3578             : 
    3579       34412 :                 newntest = makeNode(NullTest);
    3580       34412 :                 newntest->arg = (Expr *) arg;
    3581       34412 :                 newntest->nulltesttype = ntest->nulltesttype;
    3582       34412 :                 newntest->argisrow = ntest->argisrow;
    3583       34412 :                 newntest->location = ntest->location;
    3584       34412 :                 return (Node *) newntest;
    3585             :             }
    3586        1928 :         case T_BooleanTest:
    3587             :             {
    3588             :                 /*
    3589             :                  * This case could be folded into the generic handling used
    3590             :                  * for ArrayExpr etc.  But because the simplification logic is
    3591             :                  * so trivial, applying evaluate_expr() to perform it would be
    3592             :                  * a heavy overhead.  BooleanTest is probably common enough to
    3593             :                  * justify keeping this bespoke implementation.
    3594             :                  */
    3595        1928 :                 BooleanTest *btest = (BooleanTest *) node;
    3596             :                 BooleanTest *newbtest;
    3597             :                 Node       *arg;
    3598             : 
    3599        1928 :                 arg = eval_const_expressions_mutator((Node *) btest->arg,
    3600             :                                                      context);
    3601        1928 :                 if (arg && IsA(arg, Const))
    3602             :                 {
    3603         222 :                     Const      *carg = (Const *) arg;
    3604             :                     bool        result;
    3605             : 
    3606         222 :                     switch (btest->booltesttype)
    3607             :                     {
    3608           0 :                         case IS_TRUE:
    3609           0 :                             result = (!carg->constisnull &&
    3610           0 :                                       DatumGetBool(carg->constvalue));
    3611           0 :                             break;
    3612         222 :                         case IS_NOT_TRUE:
    3613         444 :                             result = (carg->constisnull ||
    3614         222 :                                       !DatumGetBool(carg->constvalue));
    3615         222 :                             break;
    3616           0 :                         case IS_FALSE:
    3617           0 :                             result = (!carg->constisnull &&
    3618           0 :                                       !DatumGetBool(carg->constvalue));
    3619           0 :                             break;
    3620           0 :                         case IS_NOT_FALSE:
    3621           0 :                             result = (carg->constisnull ||
    3622           0 :                                       DatumGetBool(carg->constvalue));
    3623           0 :                             break;
    3624           0 :                         case IS_UNKNOWN:
    3625           0 :                             result = carg->constisnull;
    3626           0 :                             break;
    3627           0 :                         case IS_NOT_UNKNOWN:
    3628           0 :                             result = !carg->constisnull;
    3629           0 :                             break;
    3630           0 :                         default:
    3631           0 :                             elog(ERROR, "unrecognized booltesttype: %d",
    3632             :                                  (int) btest->booltesttype);
    3633             :                             result = false; /* keep compiler quiet */
    3634             :                             break;
    3635             :                     }
    3636             : 
    3637         222 :                     return makeBoolConst(result, false);
    3638             :                 }
    3639             : 
    3640        1706 :                 newbtest = makeNode(BooleanTest);
    3641        1706 :                 newbtest->arg = (Expr *) arg;
    3642        1706 :                 newbtest->booltesttype = btest->booltesttype;
    3643        1706 :                 newbtest->location = btest->location;
    3644        1706 :                 return (Node *) newbtest;
    3645             :             }
    3646       27594 :         case T_CoerceToDomain:
    3647             :             {
    3648             :                 /*
    3649             :                  * If the domain currently has no constraints, we replace the
    3650             :                  * CoerceToDomain node with a simple RelabelType, which is
    3651             :                  * both far faster to execute and more amenable to later
    3652             :                  * optimization.  We must then mark the plan as needing to be
    3653             :                  * rebuilt if the domain's constraints change.
    3654             :                  *
    3655             :                  * Also, in estimation mode, always replace CoerceToDomain
    3656             :                  * nodes, effectively assuming that the coercion will succeed.
    3657             :                  */
    3658       27594 :                 CoerceToDomain *cdomain = (CoerceToDomain *) node;
    3659             :                 CoerceToDomain *newcdomain;
    3660             :                 Node       *arg;
    3661             : 
    3662       27594 :                 arg = eval_const_expressions_mutator((Node *) cdomain->arg,
    3663             :                                                      context);
    3664       27564 :                 if (context->estimate ||
    3665       27516 :                     !DomainHasConstraints(cdomain->resulttype))
    3666             :                 {
    3667             :                     /* Record dependency, if this isn't estimation mode */
    3668       18346 :                     if (context->root && !context->estimate)
    3669       18232 :                         record_plan_type_dependency(context->root,
    3670             :                                                     cdomain->resulttype);
    3671             : 
    3672             :                     /* Generate RelabelType to substitute for CoerceToDomain */
    3673       18346 :                     return applyRelabelType(arg,
    3674             :                                             cdomain->resulttype,
    3675             :                                             cdomain->resulttypmod,
    3676             :                                             cdomain->resultcollid,
    3677             :                                             cdomain->coercionformat,
    3678             :                                             cdomain->location,
    3679             :                                             true);
    3680             :                 }
    3681             : 
    3682        9218 :                 newcdomain = makeNode(CoerceToDomain);
    3683        9218 :                 newcdomain->arg = (Expr *) arg;
    3684        9218 :                 newcdomain->resulttype = cdomain->resulttype;
    3685        9218 :                 newcdomain->resulttypmod = cdomain->resulttypmod;
    3686        9218 :                 newcdomain->resultcollid = cdomain->resultcollid;
    3687        9218 :                 newcdomain->coercionformat = cdomain->coercionformat;
    3688        9218 :                 newcdomain->location = cdomain->location;
    3689        9218 :                 return (Node *) newcdomain;
    3690             :             }
    3691        3712 :         case T_PlaceHolderVar:
    3692             : 
    3693             :             /*
    3694             :              * In estimation mode, just strip the PlaceHolderVar node
    3695             :              * altogether; this amounts to estimating that the contained value
    3696             :              * won't be forced to null by an outer join.  In regular mode we
    3697             :              * just use the default behavior (ie, simplify the expression but
    3698             :              * leave the PlaceHolderVar node intact).
    3699             :              */
    3700        3712 :             if (context->estimate)
    3701             :             {
    3702         354 :                 PlaceHolderVar *phv = (PlaceHolderVar *) node;
    3703             : 
    3704         354 :                 return eval_const_expressions_mutator((Node *) phv->phexpr,
    3705             :                                                       context);
    3706             :             }
    3707        3358 :             break;
    3708          90 :         case T_ConvertRowtypeExpr:
    3709             :             {
    3710          90 :                 ConvertRowtypeExpr *cre = castNode(ConvertRowtypeExpr, node);
    3711             :                 Node       *arg;
    3712             :                 ConvertRowtypeExpr *newcre;
    3713             : 
    3714          90 :                 arg = eval_const_expressions_mutator((Node *) cre->arg,
    3715             :                                                      context);
    3716             : 
    3717          90 :                 newcre = makeNode(ConvertRowtypeExpr);
    3718          90 :                 newcre->resulttype = cre->resulttype;
    3719          90 :                 newcre->convertformat = cre->convertformat;
    3720          90 :                 newcre->location = cre->location;
    3721             : 
    3722             :                 /*
    3723             :                  * In case of a nested ConvertRowtypeExpr, we can convert the
    3724             :                  * leaf row directly to the topmost row format without any
    3725             :                  * intermediate conversions. (This works because
    3726             :                  * ConvertRowtypeExpr is used only for child->parent
    3727             :                  * conversion in inheritance trees, which works by exact match
    3728             :                  * of column name, and a column absent in an intermediate
    3729             :                  * result can't be present in the final result.)
    3730             :                  *
    3731             :                  * No need to check more than one level deep, because the
    3732             :                  * above recursion will have flattened anything else.
    3733             :                  */
    3734          90 :                 if (arg != NULL && IsA(arg, ConvertRowtypeExpr))
    3735             :                 {
    3736          12 :                     ConvertRowtypeExpr *argcre = (ConvertRowtypeExpr *) arg;
    3737             : 
    3738          12 :                     arg = (Node *) argcre->arg;
    3739             : 
    3740             :                     /*
    3741             :                      * Make sure an outer implicit conversion can't hide an
    3742             :                      * inner explicit one.
    3743             :                      */
    3744          12 :                     if (newcre->convertformat == COERCE_IMPLICIT_CAST)
    3745           0 :                         newcre->convertformat = argcre->convertformat;
    3746             :                 }
    3747             : 
    3748          90 :                 newcre->arg = (Expr *) arg;
    3749             : 
    3750          90 :                 if (arg != NULL && IsA(arg, Const))
    3751          18 :                     return ece_evaluate_expr((Node *) newcre);
    3752          72 :                 return (Node *) newcre;
    3753             :             }
    3754     6639698 :         default:
    3755     6639698 :             break;
    3756             :     }
    3757             : 
    3758             :     /*
    3759             :      * For any node type not handled above, copy the node unchanged but
    3760             :      * const-simplify its subexpressions.  This is the correct thing for node
    3761             :      * types whose behavior might change between planning and execution, such
    3762             :      * as CurrentOfExpr.  It's also a safe default for new node types not
    3763             :      * known to this routine.
    3764             :      */
    3765     6643056 :     return ece_generic_processing(node);
    3766             : }
    3767             : 
    3768             : /*
    3769             :  * Subroutine for eval_const_expressions: check for non-Const nodes.
    3770             :  *
    3771             :  * We can abort recursion immediately on finding a non-Const node.  This is
    3772             :  * critical for performance, else eval_const_expressions_mutator would take
    3773             :  * O(N^2) time on non-simplifiable trees.  However, we do need to descend
    3774             :  * into List nodes since expression_tree_walker sometimes invokes the walker
    3775             :  * function directly on List subtrees.
    3776             :  */
    3777             : static bool
    3778      210446 : contain_non_const_walker(Node *node, void *context)
    3779             : {
    3780      210446 :     if (node == NULL)
    3781         712 :         return false;
    3782      209734 :     if (IsA(node, Const))
    3783      107176 :         return false;
    3784      102558 :     if (IsA(node, List))
    3785       35420 :         return expression_tree_walker(node, contain_non_const_walker, context);
    3786             :     /* Otherwise, abort the tree traversal and return true */
    3787       67138 :     return true;
    3788             : }
    3789             : 
    3790             : /*
    3791             :  * Subroutine for eval_const_expressions: check if a function is OK to evaluate
    3792             :  */
    3793             : static bool
    3794         376 : ece_function_is_safe(Oid funcid, eval_const_expressions_context *context)
    3795             : {
    3796         376 :     char        provolatile = func_volatile(funcid);
    3797             : 
    3798             :     /*
    3799             :      * Ordinarily we are only allowed to simplify immutable functions. But for
    3800             :      * purposes of estimation, we consider it okay to simplify functions that
    3801             :      * are merely stable; the risk that the result might change from planning
    3802             :      * time to execution time is worth taking in preference to not being able
    3803             :      * to estimate the value at all.
    3804             :      */
    3805         376 :     if (provolatile == PROVOLATILE_IMMUTABLE)
    3806         376 :         return true;
    3807           0 :     if (context->estimate && provolatile == PROVOLATILE_STABLE)
    3808           0 :         return true;
    3809           0 :     return false;
    3810             : }
    3811             : 
    3812             : /*
    3813             :  * Subroutine for eval_const_expressions: process arguments of an OR clause
    3814             :  *
    3815             :  * This includes flattening of nested ORs as well as recursion to
    3816             :  * eval_const_expressions to simplify the OR arguments.
    3817             :  *
    3818             :  * After simplification, OR arguments are handled as follows:
    3819             :  *      non constant: keep
    3820             :  *      FALSE: drop (does not affect result)
    3821             :  *      TRUE: force result to TRUE
    3822             :  *      NULL: keep only one
    3823             :  * We must keep one NULL input because OR expressions evaluate to NULL when no
    3824             :  * input is TRUE and at least one is NULL.  We don't actually include the NULL
    3825             :  * here, that's supposed to be done by the caller.
    3826             :  *
    3827             :  * The output arguments *haveNull and *forceTrue must be initialized false
    3828             :  * by the caller.  They will be set true if a NULL constant or TRUE constant,
    3829             :  * respectively, is detected anywhere in the argument list.
    3830             :  */
    3831             : static List *
    3832       12480 : simplify_or_arguments(List *args,
    3833             :                       eval_const_expressions_context *context,
    3834             :                       bool *haveNull, bool *forceTrue)
    3835             : {
    3836       12480 :     List       *newargs = NIL;
    3837             :     List       *unprocessed_args;
    3838             : 
    3839             :     /*
    3840             :      * We want to ensure that any OR immediately beneath another OR gets
    3841             :      * flattened into a single OR-list, so as to simplify later reasoning.
    3842             :      *
    3843             :      * To avoid stack overflow from recursion of eval_const_expressions, we
    3844             :      * resort to some tenseness here: we keep a list of not-yet-processed
    3845             :      * inputs, and handle flattening of nested ORs by prepending to the to-do
    3846             :      * list instead of recursing.  Now that the parser generates N-argument
    3847             :      * ORs from simple lists, this complexity is probably less necessary than
    3848             :      * it once was, but we might as well keep the logic.
    3849             :      */
    3850       12480 :     unprocessed_args = list_copy(args);
    3851       42042 :     while (unprocessed_args)
    3852             :     {
    3853       29730 :         Node       *arg = (Node *) linitial(unprocessed_args);
    3854             : 
    3855       29730 :         unprocessed_args = list_delete_first(unprocessed_args);
    3856             : 
    3857             :         /* flatten nested ORs as per above comment */
    3858       29730 :         if (is_orclause(arg))
    3859           6 :         {
    3860           6 :             List       *subargs = ((BoolExpr *) arg)->args;
    3861           6 :             List       *oldlist = unprocessed_args;
    3862             : 
    3863           6 :             unprocessed_args = list_concat_copy(subargs, unprocessed_args);
    3864             :             /* perhaps-overly-tense code to avoid leaking old lists */
    3865           6 :             list_free(oldlist);
    3866           6 :             continue;
    3867             :         }
    3868             : 
    3869             :         /* If it's not an OR, simplify it */
    3870       29724 :         arg = eval_const_expressions_mutator(arg, context);
    3871             : 
    3872             :         /*
    3873             :          * It is unlikely but not impossible for simplification of a non-OR
    3874             :          * clause to produce an OR.  Recheck, but don't be too tense about it
    3875             :          * since it's not a mainstream case.  In particular we don't worry
    3876             :          * about const-simplifying the input twice, nor about list leakage.
    3877             :          */
    3878       29724 :         if (is_orclause(arg))
    3879           0 :         {
    3880           0 :             List       *subargs = ((BoolExpr *) arg)->args;
    3881             : 
    3882           0 :             unprocessed_args = list_concat_copy(subargs, unprocessed_args);
    3883           0 :             continue;
    3884             :         }
    3885             : 
    3886             :         /*
    3887             :          * OK, we have a const-simplified non-OR argument.  Process it per
    3888             :          * comments above.
    3889             :          */
    3890       29724 :         if (IsA(arg, Const))
    3891         236 :         {
    3892         404 :             Const      *const_input = (Const *) arg;
    3893             : 
    3894         404 :             if (const_input->constisnull)
    3895          48 :                 *haveNull = true;
    3896         356 :             else if (DatumGetBool(const_input->constvalue))
    3897             :             {
    3898         168 :                 *forceTrue = true;
    3899             : 
    3900             :                 /*
    3901             :                  * Once we detect a TRUE result we can just exit the loop
    3902             :                  * immediately.  However, if we ever add a notion of
    3903             :                  * non-removable functions, we'd need to keep scanning.
    3904             :                  */
    3905         168 :                 return NIL;
    3906             :             }
    3907             :             /* otherwise, we can drop the constant-false input */
    3908         236 :             continue;
    3909             :         }
    3910             : 
    3911             :         /* else emit the simplified arg into the result list */
    3912       29320 :         newargs = lappend(newargs, arg);
    3913             :     }
    3914             : 
    3915       12312 :     return newargs;
    3916             : }
    3917             : 
    3918             : /*
    3919             :  * Subroutine for eval_const_expressions: process arguments of an AND clause
    3920             :  *
    3921             :  * This includes flattening of nested ANDs as well as recursion to
    3922             :  * eval_const_expressions to simplify the AND arguments.
    3923             :  *
    3924             :  * After simplification, AND arguments are handled as follows:
    3925             :  *      non constant: keep
    3926             :  *      TRUE: drop (does not affect result)
    3927             :  *      FALSE: force result to FALSE
    3928             :  *      NULL: keep only one
    3929             :  * We must keep one NULL input because AND expressions evaluate to NULL when
    3930             :  * no input is FALSE and at least one is NULL.  We don't actually include the
    3931             :  * NULL here, that's supposed to be done by the caller.
    3932             :  *
    3933             :  * The output arguments *haveNull and *forceFalse must be initialized false
    3934             :  * by the caller.  They will be set true if a null constant or false constant,
    3935             :  * respectively, is detected anywhere in the argument list.
    3936             :  */
    3937             : static List *
    3938      141754 : simplify_and_arguments(List *args,
    3939             :                        eval_const_expressions_context *context,
    3940             :                        bool *haveNull, bool *forceFalse)
    3941             : {
    3942      141754 :     List       *newargs = NIL;
    3943             :     List       *unprocessed_args;
    3944             : 
    3945             :     /* See comments in simplify_or_arguments */
    3946      141754 :     unprocessed_args = list_copy(args);
    3947      521854 :     while (unprocessed_args)
    3948             :     {
    3949      381654 :         Node       *arg = (Node *) linitial(unprocessed_args);
    3950             : 
    3951      381654 :         unprocessed_args = list_delete_first(unprocessed_args);
    3952             : 
    3953             :         /* flatten nested ANDs as per above comment */
    3954      381654 :         if (is_andclause(arg))
    3955        2114 :         {
    3956        2114 :             List       *subargs = ((BoolExpr *) arg)->args;
    3957        2114 :             List       *oldlist = unprocessed_args;
    3958             : 
    3959        2114 :             unprocessed_args = list_concat_copy(subargs, unprocessed_args);
    3960             :             /* perhaps-overly-tense code to avoid leaking old lists */
    3961        2114 :             list_free(oldlist);
    3962        2114 :             continue;
    3963             :         }
    3964             : 
    3965             :         /* If it's not an AND, simplify it */
    3966      379540 :         arg = eval_const_expressions_mutator(arg, context);
    3967             : 
    3968             :         /*
    3969             :          * It is unlikely but not impossible for simplification of a non-AND
    3970             :          * clause to produce an AND.  Recheck, but don't be too tense about it
    3971             :          * since it's not a mainstream case.  In particular we don't worry
    3972             :          * about const-simplifying the input twice, nor about list leakage.
    3973             :          */
    3974      379540 :         if (is_andclause(arg))
    3975          36 :         {
    3976          36 :             List       *subargs = ((BoolExpr *) arg)->args;
    3977             : 
    3978          36 :             unprocessed_args = list_concat_copy(subargs, unprocessed_args);
    3979          36 :             continue;
    3980             :         }
    3981             : 
    3982             :         /*
    3983             :          * OK, we have a const-simplified non-AND argument.  Process it per
    3984             :          * comments above.
    3985             :          */
    3986      379504 :         if (IsA(arg, Const))
    3987        1976 :         {
    3988        3530 :             Const      *const_input = (Const *) arg;
    3989             : 
    3990        3530 :             if (const_input->constisnull)
    3991          18 :                 *haveNull = true;
    3992        3512 :             else if (!DatumGetBool(const_input->constvalue))
    3993             :             {
    3994        1554 :                 *forceFalse = true;
    3995             : 
    3996             :                 /*
    3997             :                  * Once we detect a FALSE result we can just exit the loop
    3998             :                  * immediately.  However, if we ever add a notion of
    3999             :                  * non-removable functions, we'd need to keep scanning.
    4000             :                  */
    4001        1554 :                 return NIL;
    4002             :             }
    4003             :             /* otherwise, we can drop the constant-true input */
    4004        1976 :             continue;
    4005             :         }
    4006             : 
    4007             :         /* else emit the simplified arg into the result list */
    4008      375974 :         newargs = lappend(newargs, arg);
    4009             :     }
    4010             : 
    4011      140200 :     return newargs;
    4012             : }
    4013             : 
    4014             : /*
    4015             :  * Subroutine for eval_const_expressions: try to simplify boolean equality
    4016             :  * or inequality condition
    4017             :  *
    4018             :  * Inputs are the operator OID and the simplified arguments to the operator.
    4019             :  * Returns a simplified expression if successful, or NULL if cannot
    4020             :  * simplify the expression.
    4021             :  *
    4022             :  * The idea here is to reduce "x = true" to "x" and "x = false" to "NOT x",
    4023             :  * or similarly "x <> true" to "NOT x" and "x <> false" to "x".
    4024             :  * This is only marginally useful in itself, but doing it in constant folding
    4025             :  * ensures that we will recognize these forms as being equivalent in, for
    4026             :  * example, partial index matching.
    4027             :  *
    4028             :  * We come here only if simplify_function has failed; therefore we cannot
    4029             :  * see two constant inputs, nor a constant-NULL input.
    4030             :  */
    4031             : static Node *
    4032        1304 : simplify_boolean_equality(Oid opno, List *args)
    4033             : {
    4034             :     Node       *leftop;
    4035             :     Node       *rightop;
    4036             : 
    4037             :     Assert(list_length(args) == 2);
    4038        1304 :     leftop = linitial(args);
    4039        1304 :     rightop = lsecond(args);
    4040        1304 :     if (leftop && IsA(leftop, Const))
    4041             :     {
    4042             :         Assert(!((Const *) leftop)->constisnull);
    4043           0 :         if (opno == BooleanEqualOperator)
    4044             :         {
    4045           0 :             if (DatumGetBool(((Const *) leftop)->constvalue))
    4046           0 :                 return rightop; /* true = foo */
    4047             :             else
    4048           0 :                 return negate_clause(rightop);  /* false = foo */
    4049             :         }
    4050             :         else
    4051             :         {
    4052           0 :             if (DatumGetBool(((Const *) leftop)->constvalue))
    4053           0 :                 return negate_clause(rightop);  /* true <> foo */
    4054             :             else
    4055           0 :                 return rightop; /* false <> foo */
    4056             :         }
    4057             :     }
    4058        1304 :     if (rightop && IsA(rightop, Const))
    4059             :     {
    4060             :         Assert(!((Const *) rightop)->constisnull);
    4061        1042 :         if (opno == BooleanEqualOperator)
    4062             :         {
    4063         976 :             if (DatumGetBool(((Const *) rightop)->constvalue))
    4064         230 :                 return leftop;  /* foo = true */
    4065             :             else
    4066         746 :                 return negate_clause(leftop);   /* foo = false */
    4067             :         }
    4068             :         else
    4069             :         {
    4070          66 :             if (DatumGetBool(((Const *) rightop)->constvalue))
    4071          60 :                 return negate_clause(leftop);   /* foo <> true */
    4072             :             else
    4073           6 :                 return leftop;  /* foo <> false */
    4074             :         }
    4075             :     }
    4076         262 :     return NULL;
    4077             : }
    4078             : 
    4079             : /*
    4080             :  * Subroutine for eval_const_expressions: try to simplify a function call
    4081             :  * (which might originally have been an operator; we don't care)
    4082             :  *
    4083             :  * Inputs are the function OID, actual result type OID (which is needed for
    4084             :  * polymorphic functions), result typmod, result collation, the input
    4085             :  * collation to use for the function, the original argument list (not
    4086             :  * const-simplified yet, unless process_args is false), and some flags;
    4087             :  * also the context data for eval_const_expressions.
    4088             :  *
    4089             :  * Returns a simplified expression if successful, or NULL if cannot
    4090             :  * simplify the function call.
    4091             :  *
    4092             :  * This function is also responsible for converting named-notation argument
    4093             :  * lists into positional notation and/or adding any needed default argument
    4094             :  * expressions; which is a bit grotty, but it avoids extra fetches of the
    4095             :  * function's pg_proc tuple.  For this reason, the args list is
    4096             :  * pass-by-reference.  Conversion and const-simplification of the args list
    4097             :  * will be done even if simplification of the function call itself is not
    4098             :  * possible.
    4099             :  */
    4100             : static Expr *
    4101     1248458 : simplify_function(Oid funcid, Oid result_type, int32 result_typmod,
    4102             :                   Oid result_collid, Oid input_collid, List **args_p,
    4103             :                   bool funcvariadic, bool process_args, bool allow_non_const,
    4104             :                   eval_const_expressions_context *context)
    4105             : {
    4106     1248458 :     List       *args = *args_p;
    4107             :     HeapTuple   func_tuple;
    4108             :     Form_pg_proc func_form;
    4109             :     Expr       *newexpr;
    4110             : 
    4111             :     /*
    4112             :      * We have three strategies for simplification: execute the function to
    4113             :      * deliver a constant result, use a transform function to generate a
    4114             :      * substitute node tree, or expand in-line the body of the function
    4115             :      * definition (which only works for simple SQL-language functions, but
    4116             :      * that is a common case).  Each case needs access to the function's
    4117             :      * pg_proc tuple, so fetch it just once.
    4118             :      *
    4119             :      * Note: the allow_non_const flag suppresses both the second and third
    4120             :      * strategies; so if !allow_non_const, simplify_function can only return a
    4121             :      * Const or NULL.  Argument-list rewriting happens anyway, though.
    4122             :      */
    4123     1248458 :     func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid));
    4124     1248458 :     if (!HeapTupleIsValid(func_tuple))
    4125           0 :         elog(ERROR, "cache lookup failed for function %u", funcid);
    4126     1248458 :     func_form = (Form_pg_proc) GETSTRUCT(func_tuple);
    4127             : 
    4128             :     /*
    4129             :      * Process the function arguments, unless the caller did it already.
    4130             :      *
    4131             :      * Here we must deal with named or defaulted arguments, and then
    4132             :      * recursively apply eval_const_expressions to the whole argument list.
    4133             :      */
    4134     1248458 :     if (process_args)
    4135             :     {
    4136     1246098 :         args = expand_function_arguments(args, false, result_type, func_tuple);
    4137     1246098 :         args = (List *) expression_tree_mutator((Node *) args,
    4138             :                                                 eval_const_expressions_mutator,
    4139             :                                                 context);
    4140             :         /* Argument processing done, give it back to the caller */
    4141     1245972 :         *args_p = args;
    4142             :     }
    4143             : 
    4144             :     /* Now attempt simplification of the function call proper. */
    4145             : 
    4146     1248332 :     newexpr = evaluate_function(funcid, result_type, result_typmod,
    4147             :                                 result_collid, input_collid,
    4148             :                                 args, funcvariadic,
    4149             :                                 func_tuple, context);
    4150             : 
    4151     1244472 :     if (!newexpr && allow_non_const && OidIsValid(func_form->prosupport))
    4152             :     {
    4153             :         /*
    4154             :          * Build a SupportRequestSimplify node to pass to the support
    4155             :          * function, pointing to a dummy FuncExpr node containing the
    4156             :          * simplified arg list.  We use this approach to present a uniform
    4157             :          * interface to the support function regardless of how the target
    4158             :          * function is actually being invoked.
    4159             :          */
    4160             :         SupportRequestSimplify req;
    4161             :         FuncExpr    fexpr;
    4162             : 
    4163       33944 :         fexpr.xpr.type = T_FuncExpr;
    4164       33944 :         fexpr.funcid = funcid;
    4165       33944 :         fexpr.funcresulttype = result_type;
    4166       33944 :         fexpr.funcretset = func_form->proretset;
    4167       33944 :         fexpr.funcvariadic = funcvariadic;
    4168       33944 :         fexpr.funcformat = COERCE_EXPLICIT_CALL;
    4169       33944 :         fexpr.funccollid = result_collid;
    4170       33944 :         fexpr.inputcollid = input_collid;
    4171       33944 :         fexpr.args = args;
    4172       33944 :         fexpr.location = -1;
    4173             : 
    4174       33944 :         req.type = T_SupportRequestSimplify;
    4175       33944 :         req.root = context->root;
    4176       33944 :         req.fcall = &fexpr;
    4177             : 
    4178             :         newexpr = (Expr *)
    4179       33944 :             DatumGetPointer(OidFunctionCall1(func_form->prosupport,
    4180             :                                              PointerGetDatum(&req)));
    4181             : 
    4182             :         /* catch a possible API misunderstanding */
    4183             :         Assert(newexpr != (Expr *) &fexpr);
    4184             :     }
    4185             : 
    4186     1244472 :     if (!newexpr && allow_non_const)
    4187     1065988 :         newexpr = inline_function(funcid, result_type, result_collid,
    4188             :                                   input_collid, args, funcvariadic,
    4189             :                                   func_tuple, context);
    4190             : 
    4191     1244458 :     ReleaseSysCache(func_tuple);
    4192             : 
    4193     1244458 :     return newexpr;
    4194             : }
    4195             : 
    4196             : /*
    4197             :  * var_is_nonnullable: check to see if the Var cannot be NULL
    4198             :  *
    4199             :  * If the Var is defined NOT NULL and meanwhile is not nulled by any outer
    4200             :  * joins or grouping sets, then we can know that it cannot be NULL.
    4201             :  *
    4202             :  * use_rel_info indicates whether the corresponding RelOptInfo is available for
    4203             :  * use.
    4204             :  */
    4205             : bool
    4206       26496 : var_is_nonnullable(PlannerInfo *root, Var *var, bool use_rel_info)
    4207             : {
    4208       26496 :     Bitmapset  *notnullattnums = NULL;
    4209             : 
    4210             :     Assert(IsA(var, Var));
    4211             : 
    4212             :     /* skip upper-level Vars */
    4213       26496 :     if (var->varlevelsup != 0)
    4214           6 :         return false;
    4215             : 
    4216             :     /* could the Var be nulled by any outer joins or grouping sets? */
    4217       26490 :     if (!bms_is_empty(var->varnullingrels))
    4218        3076 :         return false;
    4219             : 
    4220             :     /* system columns cannot be NULL */
    4221       23414 :     if (var->varattno < 0)
    4222          24 :         return true;
    4223             : 
    4224             :     /*
    4225             :      * Check if the Var is defined as NOT NULL.  We retrieve the column NOT
    4226             :      * NULL constraint information from the corresponding RelOptInfo if it is
    4227             :      * available; otherwise, we search the hash table for this information.
    4228             :      */
    4229       23390 :     if (use_rel_info)
    4230             :     {
    4231        9280 :         RelOptInfo *rel = find_base_rel(root, var->varno);
    4232             : 
    4233        9280 :         notnullattnums = rel->notnullattnums;
    4234             :     }
    4235             :     else
    4236             :     {
    4237       14110 :         RangeTblEntry *rte = planner_rt_fetch(var->varno, root);
    4238             : 
    4239             :         /*
    4240             :          * We must skip inheritance parent tables, as some child tables may
    4241             :          * have a NOT NULL constraint for a column while others may not.  This
    4242             :          * cannot happen with partitioned tables, though.
    4243             :          */
    4244       14110 :         if (rte->inh && rte->relkind != RELKIND_PARTITIONED_TABLE)
    4245         144 :             return false;
    4246             : 
    4247       13966 :         notnullattnums = find_relation_notnullatts(root, rte->relid);
    4248             :     }
    4249             : 
    4250       46480 :     if (var->varattno > 0 &&
    4251       23234 :         bms_is_member(var->varattno, notnullattnums))
    4252         894 :         return true;
    4253             : 
    4254       22352 :     return false;
    4255             : }
    4256             : 
    4257             : /*
    4258             :  * expand_function_arguments: convert named-notation args to positional args
    4259             :  * and/or insert default args, as needed
    4260             :  *
    4261             :  * Returns a possibly-transformed version of the args list.
    4262             :  *
    4263             :  * If include_out_arguments is true, then the args list and the result
    4264             :  * include OUT arguments.
    4265             :  *
    4266             :  * The expected result type of the call must be given, for sanity-checking
    4267             :  * purposes.  Also, we ask the caller to provide the function's actual
    4268             :  * pg_proc tuple, not just its OID.
    4269             :  *
    4270             :  * If we need to change anything, the input argument list is copied, not
    4271             :  * modified.
    4272             :  *
    4273             :  * Note: this gets applied to operator argument lists too, even though the
    4274             :  * cases it handles should never occur there.  This should be OK since it
    4275             :  * will fall through very quickly if there's nothing to do.
    4276             :  */
    4277             : List *
    4278     1249862 : expand_function_arguments(List *args, bool include_out_arguments,
    4279             :                           Oid result_type, HeapTuple func_tuple)
    4280             : {
    4281     1249862 :     Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
    4282     1249862 :     Oid        *proargtypes = funcform->proargtypes.values;
    4283     1249862 :     int         pronargs = funcform->pronargs;
    4284     1249862 :     bool        has_named_args = false;
    4285             :     ListCell   *lc;
    4286             : 
    4287             :     /*
    4288             :      * If we are asked to match to OUT arguments, then use the proallargtypes
    4289             :      * array (which includes those); otherwise use proargtypes (which
    4290             :      * doesn't).  Of course, if proallargtypes is null, we always use
    4291             :      * proargtypes.  (Fetching proallargtypes is annoyingly expensive
    4292             :      * considering that we may have nothing to do here, but fortunately the
    4293             :      * common case is include_out_arguments == false.)
    4294             :      */
    4295     1249862 :     if (include_out_arguments)
    4296             :     {
    4297             :         Datum       proallargtypes;
    4298             :         bool        isNull;
    4299             : 
    4300         498 :         proallargtypes = SysCacheGetAttr(PROCOID, func_tuple,
    4301             :                                          Anum_pg_proc_proallargtypes,
    4302             :                                          &isNull);
    4303         498 :         if (!isNull)
    4304             :         {
    4305         202 :             ArrayType  *arr = DatumGetArrayTypeP(proallargtypes);
    4306             : 
    4307         202 :             pronargs = ARR_DIMS(arr)[0];
    4308         202 :             if (ARR_NDIM(arr) != 1 ||
    4309         202 :                 pronargs < 0 ||
    4310         202 :                 ARR_HASNULL(arr) ||
    4311         202 :                 ARR_ELEMTYPE(arr) != OIDOID)
    4312           0 :                 elog(ERROR, "proallargtypes is not a 1-D Oid array or it contains nulls");
    4313             :             Assert(pronargs >= funcform->pronargs);
    4314         202 :             proargtypes = (Oid *) ARR_DATA_PTR(arr);
    4315             :         }
    4316             :     }
    4317             : 
    4318             :     /* Do we have any named arguments? */
    4319     3375670 :     foreach(lc, args)
    4320             :     {
    4321     2141954 :         Node       *arg = (Node *) lfirst(lc);
    4322             : 
    4323     2141954 :         if (IsA(arg, NamedArgExpr))
    4324             :         {
    4325       16146 :             has_named_args = true;
    4326       16146 :             break;
    4327             :         }
    4328             :     }
    4329             : 
    4330             :     /* If so, we must apply reorder_function_arguments */
    4331     1249862 :     if (has_named_args)
    4332             :     {
    4333       16146 :         args = reorder_function_arguments(args, pronargs, func_tuple);
    4334             :         /* Recheck argument types and add casts if needed */
    4335       16146 :         recheck_cast_function_args(args, result_type,
    4336             :                                    proargtypes, pronargs,
    4337             :                                    func_tuple);
    4338             :     }
    4339     1233716 :     else if (list_length(args) < pronargs)
    4340             :     {
    4341             :         /* No named args, but we seem to be short some defaults */
    4342        6432 :         args = add_function_defaults(args, pronargs, func_tuple);
    4343             :         /* Recheck argument types and add casts if needed */
    4344        6432 :         recheck_cast_function_args(args, result_type,
    4345             :                                    proargtypes, pronargs,
    4346             :                                    func_tuple);
    4347             :     }
    4348             : 
    4349     1249862 :     return args;
    4350             : }
    4351             : 
    4352             : /*
    4353             :  * reorder_function_arguments: convert named-notation args to positional args
    4354             :  *
    4355             :  * This function also inserts default argument values as needed, since it's
    4356             :  * impossible to form a truly valid positional call without that.
    4357             :  */
    4358             : static List *
    4359       16146 : reorder_function_arguments(List *args, int pronargs, HeapTuple func_tuple)
    4360             : {
    4361       16146 :     Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
    4362       16146 :     int         nargsprovided = list_length(args);
    4363             :     Node       *argarray[FUNC_MAX_ARGS];
    4364             :     ListCell   *lc;
    4365             :     int         i;
    4366             : 
    4367             :     Assert(nargsprovided <= pronargs);
    4368       16146 :     if (pronargs < 0 || pronargs > FUNC_MAX_ARGS)
    4369           0 :         elog(ERROR, "too many function arguments");
    4370       16146 :     memset(argarray, 0, pronargs * sizeof(Node *));
    4371             : 
    4372             :     /* Deconstruct the argument list into an array indexed by argnumber */
    4373       16146 :     i = 0;
    4374       65650 :     foreach(lc, args)
    4375             :     {
    4376       49504 :         Node       *arg = (Node *) lfirst(lc);
    4377             : 
    4378       49504 :         if (!IsA(arg, NamedArgExpr))
    4379             :         {
    4380             :             /* positional argument, assumed to precede all named args */
    4381             :             Assert(argarray[i] == NULL);
    4382        2466 :             argarray[i++] = arg;
    4383             :         }
    4384             :         else
    4385             :         {
    4386       47038 :             NamedArgExpr *na = (NamedArgExpr *) arg;
    4387             : 
    4388             :             Assert(na->argnumber >= 0 && na->argnumber < pronargs);
    4389             :             Assert(argarray[na->argnumber] == NULL);
    4390       47038 :             argarray[na->argnumber] = (Node *) na->arg;
    4391             :         }
    4392             :     }
    4393             : 
    4394             :     /*
    4395             :      * Fetch default expressions, if needed, and insert into array at proper
    4396             :      * locations (they aren't necessarily consecutive or all used)
    4397             :      */
    4398       16146 :     if (nargsprovided < pronargs)
    4399             :     {
    4400        7524 :         List       *defaults = fetch_function_defaults(func_tuple);
    4401             : 
    4402        7524 :         i = pronargs - funcform->pronargdefaults;
    4403       43032 :         foreach(lc, defaults)
    4404             :         {
    4405       35508 :             if (argarray[i] == NULL)
    4406       15238 :                 argarray[i] = (Node *) lfirst(lc);
    4407       35508 :             i++;
    4408             :         }
    4409             :     }
    4410             : 
    4411             :     /* Now reconstruct the args list in proper order */
    4412       16146 :     args = NIL;
    4413       80888 :     for (i = 0; i < pronargs; i++)
    4414             :     {
    4415             :         Assert(argarray[i] != NULL);
    4416       64742 :         args = lappend(args, argarray[i]);
    4417             :     }
    4418             : 
    4419       16146 :     return args;
    4420             : }
    4421             : 
    4422             : /*
    4423             :  * add_function_defaults: add missing function arguments from its defaults
    4424             :  *
    4425             :  * This is used only when the argument list was positional to begin with,
    4426             :  * and so we know we just need to add defaults at the end.
    4427             :  */
    4428             : static List *
    4429        6432 : add_function_defaults(List *args, int pronargs, HeapTuple func_tuple)
    4430             : {
    4431        6432 :     int         nargsprovided = list_length(args);
    4432             :     List       *defaults;
    4433             :     int         ndelete;
    4434             : 
    4435             :     /* Get all the default expressions from the pg_proc tuple */
    4436        6432 :     defaults = fetch_function_defaults(func_tuple);
    4437             : 
    4438             :     /* Delete any unused defaults from the list */
    4439        6432 :     ndelete = nargsprovided + list_length(defaults) - pronargs;
    4440        6432 :     if (ndelete < 0)
    4441           0 :         elog(ERROR, "not enough default arguments");
    4442        6432 :     if (ndelete > 0)
    4443         238 :         defaults = list_delete_first_n(defaults, ndelete);
    4444             : 
    4445             :     /* And form the combined argument list, not modifying the input list */
    4446        6432 :     return list_concat_copy(args, defaults);
    4447             : }
    4448             : 
    4449             : /*
    4450             :  * fetch_function_defaults: get function's default arguments as expression list
    4451             :  */
    4452             : static List *
    4453       13956 : fetch_function_defaults(HeapTuple func_tuple)
    4454             : {
    4455             :     List       *defaults;
    4456             :     Datum       proargdefaults;
    4457             :     char       *str;
    4458             : 
    4459       13956 :     proargdefaults = SysCacheGetAttrNotNull(PROCOID, func_tuple,
    4460             :                                             Anum_pg_proc_proargdefaults);
    4461       13956 :     str = TextDatumGetCString(proargdefaults);
    4462       13956 :     defaults = castNode(List, stringToNode(str));
    4463       13956 :     pfree(str);
    4464       13956 :     return defaults;
    4465             : }
    4466             : 
    4467             : /*
    4468             :  * recheck_cast_function_args: recheck function args and typecast as needed
    4469             :  * after adding defaults.
    4470             :  *
    4471             :  * It is possible for some of the defaulted arguments to be polymorphic;
    4472             :  * therefore we can't assume that the default expressions have the correct
    4473             :  * data types already.  We have to re-resolve polymorphics and do coercion
    4474             :  * just like the parser did.
    4475             :  *
    4476             :  * This should be a no-op if there are no polymorphic arguments,
    4477             :  * but we do it anyway to be sure.
    4478             :  *
    4479             :  * Note: if any casts are needed, the args list is modified in-place;
    4480             :  * caller should have already copied the list structure.
    4481             :  */
    4482             : static void
    4483       22578 : recheck_cast_function_args(List *args, Oid result_type,
    4484             :                            Oid *proargtypes, int pronargs,
    4485             :                            HeapTuple func_tuple)
    4486             : {
    4487       22578 :     Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
    4488             :     int         nargs;
    4489             :     Oid         actual_arg_types[FUNC_MAX_ARGS];
    4490             :     Oid         declared_arg_types[FUNC_MAX_ARGS];
    4491             :     Oid         rettype;
    4492             :     ListCell   *lc;
    4493             : 
    4494       22578 :     if (list_length(args) > FUNC_MAX_ARGS)
    4495           0 :         elog(ERROR, "too many function arguments");
    4496       22578 :     nargs = 0;
    4497      111338 :     foreach(lc, args)
    4498             :     {
    4499       88760 :         actual_arg_types[nargs++] = exprType((Node *) lfirst(lc));
    4500             :     }
    4501             :     Assert(nargs == pronargs);
    4502       22578 :     memcpy(declared_arg_types, proargtypes, pronargs * sizeof(Oid));
    4503       22578 :     rettype = enforce_generic_type_consistency(actual_arg_types,
    4504             :                                                declared_arg_types,
    4505             :                                                nargs,
    4506             :                                                funcform->prorettype,
    4507             :                                                false);
    4508             :     /* let's just check we got the same answer as the parser did ... */
    4509       22578 :     if (rettype != result_type)
    4510           0 :         elog(ERROR, "function's resolved result type changed during planning");
    4511             : 
    4512             :     /* perform any necessary typecasting of arguments */
    4513       22578 :     make_fn_arguments(NULL, args, actual_arg_types, declared_arg_types);
    4514       22578 : }
    4515             : 
    4516             : /*
    4517             :  * evaluate_function: try to pre-evaluate a function call
    4518             :  *
    4519             :  * We can do this if the function is strict and has any constant-null inputs
    4520             :  * (just return a null constant), or if the function is immutable and has all
    4521             :  * constant inputs (call it and return the result as a Const node).  In
    4522             :  * estimation mode we are willing to pre-evaluate stable functions too.
    4523             :  *
    4524             :  * Returns a simplified expression if successful, or NULL if cannot
    4525             :  * simplify the function.
    4526             :  */
    4527             : static Expr *
    4528     1248332 : evaluate_function(Oid funcid, Oid result_type, int32 result_typmod,
    4529             :                   Oid result_collid, Oid input_collid, List *args,
    4530             :                   bool funcvariadic,
    4531             :                   HeapTuple func_tuple,
    4532             :                   eval_const_expressions_context *context)
    4533             : {
    4534     1248332 :     Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
    4535     1248332 :     bool        has_nonconst_input = false;
    4536     1248332 :     bool        has_null_input = false;
    4537             :     ListCell   *arg;
    4538             :     FuncExpr   *newexpr;
    4539             : 
    4540             :     /*
    4541             :      * Can't simplify if it returns a set.
    4542             :      */
    4543     1248332 :     if (funcform->proretset)
    4544       64472 :         return NULL;
    4545             : 
    4546             :     /*
    4547             :      * Can't simplify if it returns RECORD.  The immediate problem is that it
    4548             :      * will be needing an expected tupdesc which we can't supply here.
    4549             :      *
    4550             :      * In the case where it has OUT parameters, we could build an expected
    4551             :      * tupdesc from those, but there may be other gotchas lurking.  In
    4552             :      * particular, if the function were to return NULL, we would produce a
    4553             :      * null constant with no remaining indication of which concrete record
    4554             :      * type it is.  For now, seems best to leave the function call unreduced.
    4555             :      */
    4556     1183860 :     if (funcform->prorettype == RECORDOID)
    4557        4824 :         return NULL;
    4558             : 
    4559             :     /*
    4560             :      * Check for constant inputs and especially constant-NULL inputs.
    4561             :      */
    4562     3213294 :     foreach(arg, args)
    4563             :     {
    4564     2034258 :         if (IsA(lfirst(arg), Const))
    4565      930508 :             has_null_input |= ((Const *) lfirst(arg))->constisnull;
    4566             :         else
    4567     1103750 :             has_nonconst_input = true;
    4568             :     }
    4569             : 
    4570             :     /*
    4571             :      * If the function is strict and has a constant-NULL input, it will never
    4572             :      * be called at all, so we can replace the call by a NULL constant, even
    4573             :      * if there are other inputs that aren't constant, and even if the
    4574             :      * function is not otherwise immutable.
    4575             :      */
    4576     1179036 :     if (funcform->proisstrict && has_null_input)
    4577         728 :         return (Expr *) makeNullConst(result_type, result_typmod,
    4578             :                                       result_collid);
    4579             : 
    4580             :     /*
    4581             :      * Otherwise, can simplify only if all inputs are constants. (For a
    4582             :      * non-strict function, constant NULL inputs are treated the same as
    4583             :      * constant non-NULL inputs.)
    4584             :      */
    4585     1178308 :     if (has_nonconst_input)
    4586      848546 :         return NULL;
    4587             : 
    4588             :     /*
    4589             :      * Ordinarily we are only allowed to simplify immutable functions. But for
    4590             :      * purposes of estimation, we consider it okay to simplify functions that
    4591             :      * are merely stable; the risk that the result might change from planning
    4592             :      * time to execution time is worth taking in preference to not being able
    4593             :      * to estimate the value at all.
    4594             :      */
    4595      329762 :     if (funcform->provolatile == PROVOLATILE_IMMUTABLE)
    4596             :          /* okay */ ;
    4597      150838 :     else if (context->estimate && funcform->provolatile == PROVOLATILE_STABLE)
    4598             :          /* okay */ ;
    4599             :     else
    4600      148272 :         return NULL;
    4601             : 
    4602             :     /*
    4603             :      * OK, looks like we can simplify this operator/function.
    4604             :      *
    4605             :      * Build a new FuncExpr node containing the already-simplified arguments.
    4606             :      */
    4607      181490 :     newexpr = makeNode(FuncExpr);
    4608      181490 :     newexpr->funcid = funcid;
    4609      181490 :     newexpr->funcresulttype = result_type;
    4610      181490 :     newexpr->funcretset = false;
    4611      181490 :     newexpr->funcvariadic = funcvariadic;
    4612      181490 :     newexpr->funcformat = COERCE_EXPLICIT_CALL; /* doesn't matter */
    4613      181490 :     newexpr->funccollid = result_collid; /* doesn't matter */
    4614      181490 :     newexpr->inputcollid = input_collid;
    4615      181490 :     newexpr->args = args;
    4616      181490 :     newexpr->location = -1;
    4617             : 
    4618      181490 :     return evaluate_expr((Expr *) newexpr, result_type, result_typmod,
    4619             :                          result_collid);
    4620             : }
    4621             : 
    4622             : /*
    4623             :  * inline_function: try to expand a function call inline
    4624             :  *
    4625             :  * If the function is a sufficiently simple SQL-language function
    4626             :  * (just "SELECT expression"), then we can inline it and avoid the rather
    4627             :  * high per-call overhead of SQL functions.  Furthermore, this can expose
    4628             :  * opportunities for constant-folding within the function expression.
    4629             :  *
    4630             :  * We have to beware of some special cases however.  A directly or
    4631             :  * indirectly recursive function would cause us to recurse forever,
    4632             :  * so we keep track of which functions we are already expanding and
    4633             :  * do not re-expand them.  Also, if a parameter is used more than once
    4634             :  * in the SQL-function body, we require it not to contain any volatile
    4635             :  * functions (volatiles might deliver inconsistent answers) nor to be
    4636             :  * unreasonably expensive to evaluate.  The expensiveness check not only
    4637             :  * prevents us from doing multiple evaluations of an expensive parameter
    4638             :  * at runtime, but is a safety value to limit growth of an expression due
    4639             :  * to repeated inlining.
    4640             :  *
    4641             :  * We must also beware of changing the volatility or strictness status of
    4642             :  * functions by inlining them.
    4643             :  *
    4644             :  * Also, at the moment we can't inline functions returning RECORD.  This
    4645             :  * doesn't work in the general case because it discards information such
    4646             :  * as OUT-parameter declarations.
    4647             :  *
    4648             :  * Also, context-dependent expression nodes in the argument list are trouble.
    4649             :  *
    4650             :  * Returns a simplified expression if successful, or NULL if cannot
    4651             :  * simplify the function.
    4652             :  */
    4653             : static Expr *
    4654     1065988 : inline_function(Oid funcid, Oid result_type, Oid result_collid,
    4655             :                 Oid input_collid, List *args,
    4656             :                 bool funcvariadic,
    4657             :                 HeapTuple func_tuple,
    4658             :                 eval_const_expressions_context *context)
    4659             : {
    4660     1065988 :     Form_pg_proc funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
    4661             :     char       *src;
    4662             :     Datum       tmp;
    4663             :     bool        isNull;
    4664             :     MemoryContext oldcxt;
    4665             :     MemoryContext mycxt;
    4666             :     inline_error_callback_arg callback_arg;
    4667             :     ErrorContextCallback sqlerrcontext;
    4668             :     FuncExpr   *fexpr;
    4669             :     SQLFunctionParseInfoPtr pinfo;
    4670             :     TupleDesc   rettupdesc;
    4671             :     ParseState *pstate;
    4672             :     List       *raw_parsetree_list;
    4673             :     List       *querytree_list;
    4674             :     Query      *querytree;
    4675             :     Node       *newexpr;
    4676             :     int        *usecounts;
    4677             :     ListCell   *arg;
    4678             :     int         i;
    4679             : 
    4680             :     /*
    4681             :      * Forget it if the function is not SQL-language or has other showstopper
    4682             :      * properties.  (The prokind and nargs checks are just paranoia.)
    4683             :      */
    4684     1065988 :     if (funcform->prolang != SQLlanguageId ||
    4685        8174 :         funcform->prokind != PROKIND_FUNCTION ||
    4686        8174 :         funcform->prosecdef ||
    4687        8162 :         funcform->proretset ||
    4688        6736 :         funcform->prorettype == RECORDOID ||
    4689       12818 :         !heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL) ||
    4690        6388 :         funcform->pronargs != list_length(args))
    4691     1059600 :         return NULL;
    4692             : 
    4693             :     /* Check for recursive function, and give up trying to expand if so */
    4694        6388 :     if (list_member_oid(context->active_fns, funcid))
    4695          12 :         return NULL;
    4696             : 
    4697             :     /* Check permission to call function (fail later, if not) */
    4698        6376 :     if (object_aclcheck(ProcedureRelationId, funcid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
    4699          20 :         return NULL;
    4700             : 
    4701             :     /* Check whether a plugin wants to hook function entry/exit */
    4702        6356 :     if (FmgrHookIsNeeded(funcid))
    4703           0 :         return NULL;
    4704             : 
    4705             :     /*
    4706             :      * Make a temporary memory context, so that we don't leak all the stuff
    4707             :      * that parsing might create.
    4708             :      */
    4709        6356 :     mycxt = AllocSetContextCreate(CurrentMemoryContext,
    4710             :                                   "inline_function",
    4711             :                                   ALLOCSET_DEFAULT_SIZES);
    4712        6356 :     oldcxt = MemoryContextSwitchTo(mycxt);
    4713             : 
    4714             :     /*
    4715             :      * We need a dummy FuncExpr node containing the already-simplified
    4716             :      * arguments.  (In some cases we don't really need it, but building it is
    4717             :      * cheap enough that it's not worth contortions to avoid.)
    4718             :      */
    4719        6356 :     fexpr = makeNode(FuncExpr);
    4720        6356 :     fexpr->funcid = funcid;
    4721        6356 :     fexpr->funcresulttype = result_type;
    4722        6356 :     fexpr->funcretset = false;
    4723        6356 :     fexpr->funcvariadic = funcvariadic;
    4724        6356 :     fexpr->funcformat = COERCE_EXPLICIT_CALL;    /* doesn't matter */
    4725        6356 :     fexpr->funccollid = result_collid;   /* doesn't matter */
    4726        6356 :     fexpr->inputcollid = input_collid;
    4727        6356 :     fexpr->args = args;
    4728        6356 :     fexpr->location = -1;
    4729             : 
    4730             :     /* Fetch the function body */
    4731        6356 :     tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
    4732        6356 :     src = TextDatumGetCString(tmp);
    4733             : 
    4734             :     /*
    4735             :      * Setup error traceback support for ereport().  This is so that we can
    4736             :      * finger the function that bad information came from.
    4737             :      */
    4738        6356 :     callback_arg.proname = NameStr(funcform->proname);
    4739        6356 :     callback_arg.prosrc = src;
    4740             : 
    4741        6356 :     sqlerrcontext.callback = sql_inline_error_callback;
    4742        6356 :     sqlerrcontext.arg = &callback_arg;
    4743        6356 :     sqlerrcontext.previous = error_context_stack;
    4744        6356 :     error_context_stack = &sqlerrcontext;
    4745             : 
    4746             :     /* If we have prosqlbody, pay attention to that not prosrc */
    4747        6356 :     tmp = SysCacheGetAttr(PROCOID,
    4748             :                           func_tuple,
    4749             :                           Anum_pg_proc_prosqlbody,
    4750             :                           &isNull);
    4751        6356 :     if (!isNull)
    4752             :     {
    4753             :         Node       *n;
    4754             :         List       *query_list;
    4755             : 
    4756        3320 :         n = stringToNode(TextDatumGetCString(tmp));
    4757        3320 :         if (IsA(n, List))
    4758        2484 :             query_list = linitial_node(List, castNode(List, n));
    4759             :         else
    4760         836 :             query_list = list_make1(n);
    4761        3320 :         if (list_length(query_list) != 1)
    4762           6 :             goto fail;
    4763        3314 :         querytree = linitial(query_list);
    4764             : 
    4765             :         /*
    4766             :          * Because we'll insist below that the querytree have an empty rtable
    4767             :          * and no sublinks, it cannot have any relation references that need
    4768             :          * to be locked or rewritten.  So we can omit those steps.
    4769             :          */
    4770             :     }
    4771             :     else
    4772             :     {
    4773             :         /* Set up to handle parameters while parsing the function body. */
    4774        3036 :         pinfo = prepare_sql_fn_parse_info(func_tuple,
    4775             :                                           (Node *) fexpr,
    4776             :                                           input_collid);
    4777             : 
    4778             :         /*
    4779             :          * We just do parsing and parse analysis, not rewriting, because
    4780             :          * rewriting will not affect table-free-SELECT-only queries, which is
    4781             :          * all that we care about.  Also, we can punt as soon as we detect
    4782             :          * more than one command in the function body.
    4783             :          */
    4784        3036 :         raw_parsetree_list = pg_parse_query(src);
    4785        3036 :         if (list_length(raw_parsetree_list) != 1)
    4786          58 :             goto fail;
    4787             : 
    4788        2978 :         pstate = make_parsestate(NULL);
    4789        2978 :         pstate->p_sourcetext = src;
    4790        2978 :         sql_fn_parser_setup(pstate, pinfo);
    4791             : 
    4792        2978 :         querytree = transformTopLevelStmt(pstate, linitial(raw_parsetree_list));
    4793             : 
    4794        2972 :         free_parsestate(pstate);
    4795             :     }
    4796             : 
    4797             :     /*
    4798             :      * The single command must be a simple "SELECT expression".
    4799             :      *
    4800             :      * Note: if you change the tests involved in this, see also plpgsql's
    4801             :      * exec_simple_check_plan().  That generally needs to have the same idea
    4802             :      * of what's a "simple expression", so that inlining a function that
    4803             :      * previously wasn't inlined won't change plpgsql's conclusion.
    4804             :      */
    4805        6286 :     if (!IsA(querytree, Query) ||
    4806        6286 :         querytree->commandType != CMD_SELECT ||
    4807        6168 :         querytree->hasAggs ||
    4808        6018 :         querytree->hasWindowFuncs ||
    4809        6018 :         querytree->hasTargetSRFs ||
    4810        6018 :         querytree->hasSubLinks ||
    4811        5296 :         querytree->cteList ||
    4812        5296 :         querytree->rtable ||
    4813        3472 :         querytree->jointree->fromlist ||
    4814        3472 :         querytree->jointree->quals ||
    4815        3472 :         querytree->groupClause ||
    4816        3472 :         querytree->groupingSets ||
    4817        3472 :         querytree->havingQual ||
    4818        3472 :         querytree->windowClause ||
    4819        3472 :         querytree->distinctClause ||
    4820        3472 :         querytree->sortClause ||
    4821        3472 :         querytree->limitOffset ||
    4822        3472 :         querytree->limitCount ||
    4823        6808 :         querytree->setOperations ||
    4824        3404 :         list_length(querytree->targetList) != 1)
    4825        2942 :         goto fail;
    4826             : 
    4827             :     /* If the function result is composite, resolve it */
    4828        3344 :     (void) get_expr_result_type((Node *) fexpr,
    4829             :                                 NULL,
    4830             :                                 &rettupdesc);
    4831             : 
    4832             :     /*
    4833             :      * Make sure the function (still) returns what it's declared to.  This
    4834             :      * will raise an error if wrong, but that's okay since the function would
    4835             :      * fail at runtime anyway.  Note that check_sql_fn_retval will also insert
    4836             :      * a coercion if needed to make the tlist expression match the declared
    4837             :      * type of the function.
    4838             :      *
    4839             :      * Note: we do not try this until we have verified that no rewriting was
    4840             :      * needed; that's probably not important, but let's be careful.
    4841             :      */
    4842        3344 :     querytree_list = list_make1(querytree);
    4843        3344 :     if (check_sql_fn_retval(list_make1(querytree_list),
    4844             :                             result_type, rettupdesc,
    4845        3344 :                             funcform->prokind,
    4846             :                             false))
    4847          12 :         goto fail;              /* reject whole-tuple-result cases */
    4848             : 
    4849             :     /*
    4850             :      * Given the tests above, check_sql_fn_retval shouldn't have decided to
    4851             :      * inject a projection step, but let's just make sure.
    4852             :      */
    4853        3326 :     if (querytree != linitial(querytree_list))
    4854           0 :         goto fail;
    4855             : 
    4856             :     /* Now we can grab the tlist expression */
    4857        3326 :     newexpr = (Node *) ((TargetEntry *) linitial(querytree->targetList))->expr;
    4858             : 
    4859             :     /*
    4860             :      * If the SQL function returns VOID, we can only inline it if it is a
    4861             :      * SELECT of an expression returning VOID (ie, it's just a redirection to
    4862             :      * another VOID-returning function).  In all non-VOID-returning cases,
    4863             :      * check_sql_fn_retval should ensure that newexpr returns the function's
    4864             :      * declared result type, so this test shouldn't fail otherwise; but we may
    4865             :      * as well cope gracefully if it does.
    4866             :      */
    4867        3326 :     if (exprType(newexpr) != result_type)
    4868          18 :         goto fail;
    4869             : 
    4870             :     /*
    4871             :      * Additional validity checks on the expression.  It mustn't be more
    4872             :      * volatile than the surrounding function (this is to avoid breaking hacks
    4873             :      * that involve pretending a function is immutable when it really ain't).
    4874             :      * If the surrounding function is declared strict, then the expression
    4875             :      * must contain only strict constructs and must use all of the function
    4876             :      * parameters (this is overkill, but an exact analysis is hard).
    4877             :      */
    4878        4020 :     if (funcform->provolatile == PROVOLATILE_IMMUTABLE &&
    4879         712 :         contain_mutable_functions(newexpr))
    4880          12 :         goto fail;
    4881        4244 :     else if (funcform->provolatile == PROVOLATILE_STABLE &&
    4882         948 :              contain_volatile_functions(newexpr))
    4883           0 :         goto fail;
    4884             : 
    4885        4976 :     if (funcform->proisstrict &&
    4886        1680 :         contain_nonstrict_functions(newexpr))
    4887          46 :         goto fail;
    4888             : 
    4889             :     /*
    4890             :      * If any parameter expression contains a context-dependent node, we can't
    4891             :      * inline, for fear of putting such a node into the wrong context.
    4892             :      */
    4893        3250 :     if (contain_context_dependent_node((Node *) args))
    4894           6 :         goto fail;
    4895             : 
    4896             :     /*
    4897             :      * We may be able to do it; there are still checks on parameter usage to
    4898             :      * make, but those are most easily done in combination with the actual
    4899             :      * substitution of the inputs.  So start building expression with inputs
    4900             :      * substituted.
    4901             :      */
    4902        3244 :     usecounts = (int *) palloc0(funcform->pronargs * sizeof(int));
    4903        3244 :     newexpr = substitute_actual_parameters(newexpr, funcform->pronargs,
    4904             :                                            args, usecounts);
    4905             : 
    4906             :     /* Now check for parameter usage */
    4907        3244 :     i = 0;
    4908        8598 :     foreach(arg, args)
    4909             :     {
    4910        5354 :         Node       *param = lfirst(arg);
    4911             : 
    4912        5354 :         if (usecounts[i] == 0)
    4913             :         {
    4914             :             /* Param not used at all: uncool if func is strict */
    4915         288 :             if (funcform->proisstrict)
    4916           0 :                 goto fail;
    4917             :         }
    4918        5066 :         else if (usecounts[i] != 1)
    4919             :         {
    4920             :             /* Param used multiple times: uncool if expensive or volatile */
    4921             :             QualCost    eval_cost;
    4922             : 
    4923             :             /*
    4924             :              * We define "expensive" as "contains any subplan or more than 10
    4925             :              * operators".  Note that the subplan search has to be done
    4926             :              * explicitly, since cost_qual_eval() will barf on unplanned
    4927             :              * subselects.
    4928             :              */
    4929         462 :             if (contain_subplans(param))
    4930           0 :                 goto fail;
    4931         462 :             cost_qual_eval(&eval_cost, list_make1(param), NULL);
    4932         462 :             if (eval_cost.startup + eval_cost.per_tuple >
    4933         462 :                 10 * cpu_operator_cost)
    4934           0 :                 goto fail;
    4935             : 
    4936             :             /*
    4937             :              * Check volatility last since this is more expensive than the
    4938             :              * above tests
    4939             :              */
    4940         462 :             if (contain_volatile_functions(param))
    4941           0 :                 goto fail;
    4942             :         }
    4943        5354 :         i++;
    4944             :     }
    4945             : 
    4946             :     /*
    4947             :      * Whew --- we can make the substitution.  Copy the modified expression
    4948             :      * out of the temporary memory context, and clean up.
    4949             :      */
    4950        3244 :     MemoryContextSwitchTo(oldcxt);
    4951             : 
    4952        3244 :     newexpr = copyObject(newexpr);
    4953             : 
    4954        3244 :     MemoryContextDelete(mycxt);
    4955             : 
    4956             :     /*
    4957             :      * If the result is of a collatable type, force the result to expose the
    4958             :      * correct collation.  In most cases this does not matter, but it's
    4959             :      * possible that the function result is used directly as a sort key or in
    4960             :      * other places where we expect exprCollation() to tell the truth.
    4961             :      */
    4962        3244 :     if (OidIsValid(result_collid))
    4963             :     {
    4964        1454 :         Oid         exprcoll = exprCollation(newexpr);
    4965             : 
    4966        1454 :         if (OidIsValid(exprcoll) && exprcoll != result_collid)
    4967             :         {
    4968          36 :             CollateExpr *newnode = makeNode(CollateExpr);
    4969             : 
    4970          36 :             newnode->arg = (Expr *) newexpr;
    4971          36 :             newnode->collOid = result_collid;
    4972          36 :             newnode->location = -1;
    4973             : 
    4974          36 :             newexpr = (Node *) newnode;
    4975             :         }
    4976             :     }
    4977             : 
    4978             :     /*
    4979             :      * Since there is now no trace of the function in the plan tree, we must
    4980             :      * explicitly record the plan's dependency on the function.
    4981             :      */
    4982        3244 :     if (context->root)
    4983        3020 :         record_plan_function_dependency(context->root, funcid);
    4984             : 
    4985             :     /*
    4986             :      * Recursively try to simplify the modified expression.  Here we must add
    4987             :      * the current function to the context list of active functions.
    4988             :      */
    4989        3244 :     context->active_fns = lappend_oid(context->active_fns, funcid);
    4990        3244 :     newexpr = eval_const_expressions_mutator(newexpr, context);
    4991        3242 :     context->active_fns = list_delete_last(context->active_fns);
    4992             : 
    4993        3242 :     error_context_stack = sqlerrcontext.previous;
    4994             : 
    4995        3242 :     return (Expr *) newexpr;
    4996             : 
    4997             :     /* Here if func is not inlinable: release temp memory and return NULL */
    4998        3100 : fail:
    4999        3100 :     MemoryContextSwitchTo(oldcxt);
    5000        3100 :     MemoryContextDelete(mycxt);
    5001        3100 :     error_context_stack = sqlerrcontext.previous;
    5002             : 
    5003        3100 :     return NULL;
    5004             : }
    5005             : 
    5006             : /*
    5007             :  * Replace Param nodes by appropriate actual parameters
    5008             :  */
    5009             : static Node *
    5010        3244 : substitute_actual_parameters(Node *expr, int nargs, List *args,
    5011             :                              int *usecounts)
    5012             : {
    5013             :     substitute_actual_parameters_context context;
    5014             : 
    5015        3244 :     context.nargs = nargs;
    5016        3244 :     context.args = args;
    5017        3244 :     context.usecounts = usecounts;
    5018             : 
    5019        3244 :     return substitute_actual_parameters_mutator(expr, &context);
    5020             : }
    5021             : 
    5022             : static Node *
    5023       18936 : substitute_actual_parameters_mutator(Node *node,
    5024             :                                      substitute_actual_parameters_context *context)
    5025             : {
    5026       18936 :     if (node == NULL)
    5027         564 :         return NULL;
    5028       18372 :     if (IsA(node, Param))
    5029             :     {
    5030        5564 :         Param      *param = (Param *) node;
    5031             : 
    5032        5564 :         if (param->paramkind != PARAM_EXTERN)
    5033           0 :             elog(ERROR, "unexpected paramkind: %d", (int) param->paramkind);
    5034        5564 :         if (param->paramid <= 0 || param->paramid > context->nargs)
    5035           0 :             elog(ERROR, "invalid paramid: %d", param->paramid);
    5036             : 
    5037             :         /* Count usage of parameter */
    5038        5564 :         context->usecounts[param->paramid - 1]++;
    5039             : 
    5040             :         /* Select the appropriate actual arg and replace the Param with it */
    5041             :         /* We don't need to copy at this time (it'll get done later) */
    5042        5564 :         return list_nth(context->args, param->paramid - 1);
    5043             :     }
    5044       12808 :     return expression_tree_mutator(node, substitute_actual_parameters_mutator, context);
    5045             : }
    5046             : 
    5047             : /*
    5048             :  * error context callback to let us supply a call-stack traceback
    5049             :  */
    5050             : static void
    5051          20 : sql_inline_error_callback(void *arg)
    5052             : {
    5053          20 :     inline_error_callback_arg *callback_arg = (inline_error_callback_arg *) arg;
    5054             :     int         syntaxerrposition;
    5055             : 
    5056             :     /* If it's a syntax error, convert to internal syntax error report */
    5057          20 :     syntaxerrposition = geterrposition();
    5058          20 :     if (syntaxerrposition > 0)
    5059             :     {
    5060           6 :         errposition(0);
    5061           6 :         internalerrposition(syntaxerrposition);
    5062           6 :         internalerrquery(callback_arg->prosrc);
    5063             :     }
    5064             : 
    5065          20 :     errcontext("SQL function \"%s\" during inlining", callback_arg->proname);
    5066          20 : }
    5067             : 
    5068             : /*
    5069             :  * evaluate_expr: pre-evaluate a constant expression
    5070             :  *
    5071             :  * We use the executor's routine ExecEvalExpr() to avoid duplication of
    5072             :  * code and ensure we get the same result as the executor would get.
    5073             :  */
    5074             : Expr *
    5075      214880 : evaluate_expr(Expr *expr, Oid result_type, int32 result_typmod,
    5076             :               Oid result_collation)
    5077             : {
    5078             :     EState     *estate;
    5079             :     ExprState  *exprstate;
    5080             :     MemoryContext oldcontext;
    5081             :     Datum       const_val;
    5082             :     bool        const_is_null;
    5083             :     int16       resultTypLen;
    5084             :     bool        resultTypByVal;
    5085             : 
    5086             :     /*
    5087             :      * To use the executor, we need an EState.
    5088             :      */
    5089      214880 :     estate = CreateExecutorState();
    5090             : 
    5091             :     /* We can use the estate's working context to avoid memory leaks. */
    5092      214880 :     oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
    5093             : 
    5094             :     /* Make sure any opfuncids are filled in. */
    5095      214880 :     fix_opfuncids((Node *) expr);
    5096             : 
    5097             :     /*
    5098             :      * Prepare expr for execution.  (Note: we can't use ExecPrepareExpr
    5099             :      * because it'd result in recursively invoking eval_const_expressions.)
    5100             :      */
    5101      214880 :     exprstate = ExecInitExpr(expr, NULL);
    5102             : 
    5103             :     /*
    5104             :      * And evaluate it.
    5105             :      *
    5106             :      * It is OK to use a default econtext because none of the ExecEvalExpr()
    5107             :      * code used in this situation will use econtext.  That might seem
    5108             :      * fortuitous, but it's not so unreasonable --- a constant expression does
    5109             :      * not depend on context, by definition, n'est ce pas?
    5110             :      */
    5111      214856 :     const_val = ExecEvalExprSwitchContext(exprstate,
    5112      214856 :                                           GetPerTupleExprContext(estate),
    5113             :                                           &const_is_null);
    5114             : 
    5115             :     /* Get info needed about result datatype */
    5116      210978 :     get_typlenbyval(result_type, &resultTypLen, &resultTypByVal);
    5117             : 
    5118             :     /* Get back to outer memory context */
    5119      210978 :     MemoryContextSwitchTo(oldcontext);
    5120             : 
    5121             :     /*
    5122             :      * Must copy result out of sub-context used by expression eval.
    5123             :      *
    5124             :      * Also, if it's varlena, forcibly detoast it.  This protects us against
    5125             :      * storing TOAST pointers into plans that might outlive the referenced
    5126             :      * data.  (makeConst would handle detoasting anyway, but it's worth a few
    5127             :      * extra lines here so that we can do the copy and detoast in one step.)
    5128             :      */
    5129      210978 :     if (!const_is_null)
    5130             :     {
    5131      209486 :         if (resultTypLen == -1)
    5132       81184 :             const_val = PointerGetDatum(PG_DETOAST_DATUM_COPY(const_val));
    5133             :         else
    5134      128302 :             const_val = datumCopy(const_val, resultTypByVal, resultTypLen);
    5135             :     }
    5136             : 
    5137             :     /* Release all the junk we just created */
    5138      210978 :     FreeExecutorState(estate);
    5139             : 
    5140             :     /*
    5141             :      * Make the constant result node.
    5142             :      */
    5143      210978 :     return (Expr *) makeConst(result_type, result_typmod, result_collation,
    5144             :                               resultTypLen,
    5145             :                               const_val, const_is_null,
    5146             :                               resultTypByVal);
    5147             : }
    5148             : 
    5149             : 
    5150             : /*
    5151             :  * inline_set_returning_function
    5152             :  *      Attempt to "inline" a set-returning function in the FROM clause.
    5153             :  *
    5154             :  * "rte" is an RTE_FUNCTION rangetable entry.  If it represents a call of a
    5155             :  * set-returning SQL function that can safely be inlined, expand the function
    5156             :  * and return the substitute Query structure.  Otherwise, return NULL.
    5157             :  *
    5158             :  * We assume that the RTE's expression has already been put through
    5159             :  * eval_const_expressions(), which among other things will take care of
    5160             :  * default arguments and named-argument notation.
    5161             :  *
    5162             :  * This has a good deal of similarity to inline_function(), but that's
    5163             :  * for the non-set-returning case, and there are enough differences to
    5164             :  * justify separate functions.
    5165             :  */
    5166             : Query *
    5167       51636 : inline_set_returning_function(PlannerInfo *root, RangeTblEntry *rte)
    5168             : {
    5169             :     RangeTblFunction *rtfunc;
    5170             :     FuncExpr   *fexpr;
    5171             :     Oid         func_oid;
    5172             :     HeapTuple   func_tuple;
    5173             :     Form_pg_proc funcform;
    5174             :     char       *src;
    5175             :     Datum       tmp;
    5176             :     bool        isNull;
    5177             :     MemoryContext oldcxt;
    5178             :     MemoryContext mycxt;
    5179             :     inline_error_callback_arg callback_arg;
    5180             :     ErrorContextCallback sqlerrcontext;
    5181             :     SQLFunctionParseInfoPtr pinfo;
    5182             :     TypeFuncClass functypclass;
    5183             :     TupleDesc   rettupdesc;
    5184             :     List       *raw_parsetree_list;
    5185             :     List       *querytree_list;
    5186             :     Query      *querytree;
    5187             : 
    5188             :     Assert(rte->rtekind == RTE_FUNCTION);
    5189             : 
    5190             :     /*
    5191             :      * It doesn't make a lot of sense for a SQL SRF to refer to itself in its
    5192             :      * own FROM clause, since that must cause infinite recursion at runtime.
    5193             :      * It will cause this code to recurse too, so check for stack overflow.
    5194             :      * (There's no need to do more.)
    5195             :      */
    5196       51636 :     check_stack_depth();
    5197             : 
    5198             :     /* Fail if the RTE has ORDINALITY - we don't implement that here. */
    5199       51636 :     if (rte->funcordinality)
    5200         932 :         return NULL;
    5201             : 
    5202             :     /* Fail if RTE isn't a single, simple FuncExpr */
    5203       50704 :     if (list_length(rte->functions) != 1)
    5204          72 :         return NULL;
    5205       50632 :     rtfunc = (RangeTblFunction *) linitial(rte->functions);
    5206             : 
    5207       50632 :     if (!IsA(rtfunc->funcexpr, FuncExpr))
    5208         414 :         return NULL;
    5209       50218 :     fexpr = (FuncExpr *) rtfunc->funcexpr;
    5210             : 
    5211       50218 :     func_oid = fexpr->funcid;
    5212             : 
    5213             :     /*
    5214             :      * The function must be declared to return a set, else inlining would
    5215             :      * change the results if the contained SELECT didn't return exactly one
    5216             :      * row.
    5217             :      */
    5218       50218 :     if (!fexpr->funcretset)
    5219        8070 :         return NULL;
    5220             : 
    5221             :     /*
    5222             :      * Refuse to inline if the arguments contain any volatile functions or
    5223             :      * sub-selects.  Volatile functions are rejected because inlining may
    5224             :      * result in the arguments being evaluated multiple times, risking a
    5225             :      * change in behavior.  Sub-selects are rejected partly for implementation
    5226             :      * reasons (pushing them down another level might change their behavior)
    5227             :      * and partly because they're likely to be expensive and so multiple
    5228             :      * evaluation would be bad.
    5229             :      */
    5230       84140 :     if (contain_volatile_functions((Node *) fexpr->args) ||
    5231       41992 :         contain_subplans((Node *) fexpr->args))
    5232         404 :         return NULL;
    5233             : 
    5234             :     /* Check permission to call function (fail later, if not) */
    5235       41744 :     if (object_aclcheck(ProcedureRelationId, func_oid, GetUserId(), ACL_EXECUTE) != ACLCHECK_OK)
    5236           8 :         return NULL;
    5237             : 
    5238             :     /* Check whether a plugin wants to hook function entry/exit */
    5239       41736 :     if (FmgrHookIsNeeded(func_oid))
    5240           0 :         return NULL;
    5241             : 
    5242             :     /*
    5243             :      * OK, let's take a look at the function's pg_proc entry.
    5244             :      */
    5245       41736 :     func_tuple = SearchSysCache1(PROCOID, ObjectIdGetDatum(func_oid));
    5246       41736 :     if (!HeapTupleIsValid(func_tuple))
    5247           0 :         elog(ERROR, "cache lookup failed for function %u", func_oid);
    5248       41736 :     funcform = (Form_pg_proc) GETSTRUCT(func_tuple);
    5249             : 
    5250             :     /*
    5251             :      * Forget it if the function is not SQL-language or has other showstopper
    5252             :      * properties.  In particular it mustn't be declared STRICT, since we
    5253             :      * couldn't enforce that.  It also mustn't be VOLATILE, because that is
    5254             :      * supposed to cause it to be executed with its own snapshot, rather than
    5255             :      * sharing the snapshot of the calling query.  We also disallow returning
    5256             :      * SETOF VOID, because inlining would result in exposing the actual result
    5257             :      * of the function's last SELECT, which should not happen in that case.
    5258             :      * (Rechecking prokind, proretset, and pronargs is just paranoia.)
    5259             :      */
    5260       41736 :     if (funcform->prolang != SQLlanguageId ||
    5261         648 :         funcform->prokind != PROKIND_FUNCTION ||
    5262         648 :         funcform->proisstrict ||
    5263         588 :         funcform->provolatile == PROVOLATILE_VOLATILE ||
    5264         234 :         funcform->prorettype == VOIDOID ||
    5265         228 :         funcform->prosecdef ||
    5266         228 :         !funcform->proretset ||
    5267         228 :         list_length(fexpr->args) != funcform->pronargs ||
    5268         228 :         !heap_attisnull(func_tuple, Anum_pg_proc_proconfig, NULL))
    5269             :     {
    5270       41508 :         ReleaseSysCache(func_tuple);
    5271       41508 :         return NULL;
    5272             :     }
    5273             : 
    5274             :     /*
    5275             :      * Make a temporary memory context, so that we don't leak all the stuff
    5276             :      * that parsing might create.
    5277             :      */
    5278         228 :     mycxt = AllocSetContextCreate(CurrentMemoryContext,
    5279             :                                   "inline_set_returning_function",
    5280             :                                   ALLOCSET_DEFAULT_SIZES);
    5281         228 :     oldcxt = MemoryContextSwitchTo(mycxt);
    5282             : 
    5283             :     /* Fetch the function body */
    5284         228 :     tmp = SysCacheGetAttrNotNull(PROCOID, func_tuple, Anum_pg_proc_prosrc);
    5285         228 :     src = TextDatumGetCString(tmp);
    5286             : 
    5287             :     /*
    5288             :      * Setup error traceback support for ereport().  This is so that we can
    5289             :      * finger the function that bad information came from.
    5290             :      */
    5291         228 :     callback_arg.proname = NameStr(funcform->proname);
    5292         228 :     callback_arg.prosrc = src;
    5293             : 
    5294         228 :     sqlerrcontext.callback = sql_inline_error_callback;
    5295         228 :     sqlerrcontext.arg = &callback_arg;
    5296         228 :     sqlerrcontext.previous = error_context_stack;
    5297         228 :     error_context_stack = &sqlerrcontext;
    5298             : 
    5299             :     /* If we have prosqlbody, pay attention to that not prosrc */
    5300         228 :     tmp = SysCacheGetAttr(PROCOID,
    5301             :                           func_tuple,
    5302             :                           Anum_pg_proc_prosqlbody,
    5303             :                           &isNull);
    5304         228 :     if (!isNull)
    5305             :     {
    5306             :         Node       *n;
    5307             : 
    5308          12 :         n = stringToNode(TextDatumGetCString(tmp));
    5309          12 :         if (IsA(n, List))
    5310          12 :             querytree_list = linitial_node(List, castNode(List, n));
    5311             :         else
    5312           0 :             querytree_list = list_make1(n);
    5313          12 :         if (list_length(querytree_list) != 1)
    5314           0 :             goto fail;
    5315          12 :         querytree = linitial(querytree_list);
    5316             : 
    5317             :         /* Acquire necessary locks, then apply rewriter. */
    5318          12 :         AcquireRewriteLocks(querytree, true, false);
    5319          12 :         querytree_list = pg_rewrite_query(querytree);
    5320          12 :         if (list_length(querytree_list) != 1)
    5321           0 :             goto fail;
    5322          12 :         querytree = linitial(querytree_list);
    5323             :     }
    5324             :     else
    5325             :     {
    5326             :         /*
    5327             :          * Set up to handle parameters while parsing the function body.  We
    5328             :          * can use the FuncExpr just created as the input for
    5329             :          * prepare_sql_fn_parse_info.
    5330             :          */
    5331         216 :         pinfo = prepare_sql_fn_parse_info(func_tuple,
    5332             :                                           (Node *) fexpr,
    5333             :                                           fexpr->inputcollid);
    5334             : 
    5335             :         /*
    5336             :          * Parse, analyze, and rewrite (unlike inline_function(), we can't
    5337             :          * skip rewriting here).  We can fail as soon as we find more than one
    5338             :          * query, though.
    5339             :          */
    5340         216 :         raw_parsetree_list = pg_parse_query(src);
    5341         216 :         if (list_length(raw_parsetree_list) != 1)
    5342           0 :             goto fail;
    5343             : 
    5344         216 :         querytree_list = pg_analyze_and_rewrite_withcb(linitial(raw_parsetree_list),
    5345             :                                                        src,
    5346             :                                                        (ParserSetupHook) sql_fn_parser_setup,
    5347             :                                                        pinfo, NULL);
    5348         216 :         if (list_length(querytree_list) != 1)
    5349           0 :             goto fail;
    5350         216 :         querytree = linitial(querytree_list);
    5351             :     }
    5352             : 
    5353             :     /*
    5354             :      * Also resolve the actual function result tupdesc, if composite.  If we
    5355             :      * have a coldeflist, believe that; otherwise use get_expr_result_type.
    5356             :      * (This logic should match ExecInitFunctionScan.)
    5357             :      */
    5358         228 :     if (rtfunc->funccolnames != NIL)
    5359             :     {
    5360          24 :         functypclass = TYPEFUNC_RECORD;
    5361          24 :         rettupdesc = BuildDescFromLists(rtfunc->funccolnames,
    5362          24 :                                         rtfunc->funccoltypes,
    5363          24 :                                         rtfunc->funccoltypmods,
    5364          24 :                                         rtfunc->funccolcollations);
    5365             :     }
    5366             :     else
    5367         204 :         functypclass = get_expr_result_type((Node *) fexpr, NULL, &rettupdesc);
    5368             : 
    5369             :     /*
    5370             :      * The single command must be a plain SELECT.
    5371             :      */
    5372         228 :     if (!IsA(querytree, Query) ||
    5373         228 :         querytree->commandType != CMD_SELECT)
    5374           0 :         goto fail;
    5375             : 
    5376             :     /*
    5377             :      * Make sure the function (still) returns what it's declared to.  This
    5378             :      * will raise an error if wrong, but that's okay since the function would
    5379             :      * fail at runtime anyway.  Note that check_sql_fn_retval will also insert
    5380             :      * coercions if needed to make the tlist expression(s) match the declared
    5381             :      * type of the function.  We also ask it to insert dummy NULL columns for
    5382             :      * any dropped columns in rettupdesc, so that the elements of the modified
    5383             :      * tlist match up to the attribute numbers.
    5384             :      *
    5385             :      * If the function returns a composite type, don't inline unless the check
    5386             :      * shows it's returning a whole tuple result; otherwise what it's
    5387             :      * returning is a single composite column which is not what we need.
    5388             :      */
    5389         228 :     if (!check_sql_fn_retval(list_make1(querytree_list),
    5390             :                              fexpr->funcresulttype, rettupdesc,
    5391         228 :                              funcform->prokind,
    5392          90 :                              true) &&
    5393          90 :         (functypclass == TYPEFUNC_COMPOSITE ||
    5394          90 :          functypclass == TYPEFUNC_COMPOSITE_DOMAIN ||
    5395             :          functypclass == TYPEFUNC_RECORD))
    5396           0 :         goto fail;              /* reject not-whole-tuple-result cases */
    5397             : 
    5398             :     /*
    5399             :      * check_sql_fn_retval might've inserted a projection step, but that's
    5400             :      * fine; just make sure we use the upper Query.
    5401             :      */
    5402         222 :     querytree = linitial_node(Query, querytree_list);
    5403             : 
    5404             :     /*
    5405             :      * Looks good --- substitute parameters into the query.
    5406             :      */
    5407         222 :     querytree = substitute_actual_srf_parameters(querytree,
    5408         222 :                                                  funcform->pronargs,
    5409             :                                                  fexpr->args);
    5410             : 
    5411             :     /*
    5412             :      * Copy the modified query out of the temporary memory context, and clean
    5413             :      * up.
    5414             :      */
    5415         222 :     MemoryContextSwitchTo(oldcxt);
    5416             : 
    5417         222 :     querytree = copyObject(querytree);
    5418             : 
    5419         222 :     MemoryContextDelete(mycxt);
    5420         222 :     error_context_stack = sqlerrcontext.previous;
    5421         222 :     ReleaseSysCache(func_tuple);
    5422             : 
    5423             :     /*
    5424             :      * We don't have to fix collations here because the upper query is already
    5425             :      * parsed, ie, the collations in the RTE are what count.
    5426             :      */
    5427             : 
    5428             :     /*
    5429             :      * Since there is now no trace of the function in the plan tree, we must
    5430             :      * explicitly record the plan's dependency on the function.
    5431             :      */
    5432         222 :     record_plan_function_dependency(root, func_oid);
    5433             : 
    5434             :     /*
    5435             :      * We must also notice if the inserted query adds a dependency on the
    5436             :      * calling role due to RLS quals.
    5437             :      */
    5438         222 :     if (querytree->hasRowSecurity)
    5439          72 :         root->glob->dependsOnRole = true;
    5440             : 
    5441         222 :     return querytree;
    5442             : 
    5443             :     /* Here if func is not inlinable: release temp memory and return NULL */
    5444           0 : fail:
    5445           0 :     MemoryContextSwitchTo(oldcxt);
    5446           0 :     MemoryContextDelete(mycxt);
    5447           0 :     error_context_stack = sqlerrcontext.previous;
    5448           0 :     ReleaseSysCache(func_tuple);
    5449             : 
    5450           0 :     return NULL;
    5451             : }
    5452             : 
    5453             : /*
    5454             :  * Replace Param nodes by appropriate actual parameters
    5455             :  *
    5456             :  * This is just enough different from substitute_actual_parameters()
    5457             :  * that it needs its own code.
    5458             :  */
    5459             : static Query *
    5460         222 : substitute_actual_srf_parameters(Query *expr, int nargs, List *args)
    5461             : {
    5462             :     substitute_actual_srf_parameters_context context;
    5463             : 
    5464         222 :     context.nargs = nargs;
    5465         222 :     context.args = args;
    5466         222 :     context.sublevels_up = 1;
    5467             : 
    5468         222 :     return query_tree_mutator(expr,
    5469             :                               substitute_actual_srf_parameters_mutator,
    5470             :                               &context,
    5471             :                               0);
    5472             : }
    5473             : 
    5474             : static Node *
    5475        8346 : substitute_actual_srf_parameters_mutator(Node *node,
    5476             :                                          substitute_actual_srf_parameters_context *context)
    5477             : {
    5478             :     Node       *result;
    5479             : 
    5480        8346 :     if (node == NULL)
    5481        4680 :         return NULL;
    5482        3666 :     if (IsA(node, Query))
    5483             :     {
    5484         150 :         context->sublevels_up++;
    5485         150 :         result = (Node *) query_tree_mutator((Query *) node,
    5486             :                                              substitute_actual_srf_parameters_mutator,
    5487             :                                              context,
    5488             :                                              0);
    5489         150 :         context->sublevels_up--;
    5490         150 :         return result;
    5491             :     }
    5492        3516 :     if (IsA(node, Param))
    5493             :     {
    5494         102 :         Param      *param = (Param *) node;
    5495             : 
    5496         102 :         if (param->paramkind == PARAM_EXTERN)
    5497             :         {
    5498         102 :             if (param->paramid <= 0 || param->paramid > context->nargs)
    5499           0 :                 elog(ERROR, "invalid paramid: %d", param->paramid);
    5500             : 
    5501             :             /*
    5502             :              * Since the parameter is being inserted into a subquery, we must
    5503             :              * adjust levels.
    5504             :              */
    5505         102 :             result = copyObject(list_nth(context->args, param->paramid - 1));
    5506         102 :             IncrementVarSublevelsUp(result, context->sublevels_up, 0);
    5507         102 :             return result;
    5508             :         }
    5509             :     }
    5510        3414 :     return expression_tree_mutator(node,
    5511             :                                    substitute_actual_srf_parameters_mutator,
    5512             :                                    context);
    5513             : }
    5514             : 
    5515             : /*
    5516             :  * pull_paramids
    5517             :  *      Returns a Bitmapset containing the paramids of all Params in 'expr'.
    5518             :  */
    5519             : Bitmapset *
    5520        1984 : pull_paramids(Expr *expr)
    5521             : {
    5522        1984 :     Bitmapset  *result = NULL;
    5523             : 
    5524        1984 :     (void) pull_paramids_walker((Node *) expr, &result);
    5525             : 
    5526        1984 :     return result;
    5527             : }
    5528             : 
    5529             : static bool
    5530        4408 : pull_paramids_walker(Node *node, Bitmapset **context)
    5531             : {
    5532        4408 :     if (node == NULL)
    5533          18 :         return false;
    5534        4390 :     if (IsA(node, Param))
    5535             :     {
    5536        2046 :         Param      *param = (Param *) node;
    5537             : 
    5538        2046 :         *context = bms_add_member(*context, param->paramid);
    5539        2046 :         return false;
    5540             :     }
    5541        2344 :     return expression_tree_walker(node, pull_paramids_walker, context);
    5542             : }
    5543             : 
    5544             : /*
    5545             :  * Build ScalarArrayOpExpr on top of 'exprs.' 'haveNonConst' indicates
    5546             :  * whether at least one of the expressions is not Const.  When it's false,
    5547             :  * the array constant is built directly; otherwise, we have to build a child
    5548             :  * ArrayExpr. The 'exprs' list gets freed if not directly used in the output
    5549             :  * expression tree.
    5550             :  */
    5551             : ScalarArrayOpExpr *
    5552        1134 : make_SAOP_expr(Oid oper, Node *leftexpr, Oid coltype, Oid arraycollid,
    5553             :                Oid inputcollid, List *exprs, bool haveNonConst)
    5554             : {
    5555        1134 :     Node       *arrayNode = NULL;
    5556        1134 :     ScalarArrayOpExpr *saopexpr = NULL;
    5557        1134 :     Oid         arraytype = get_array_type(coltype);
    5558             : 
    5559        1134 :     if (!OidIsValid(arraytype))
    5560           0 :         return NULL;
    5561             : 
    5562             :     /*
    5563             :      * Assemble an array from the list of constants.  It seems more profitable
    5564             :      * to build a const array.  But in the presence of other nodes, we don't
    5565             :      * have a specific value here and must employ an ArrayExpr instead.
    5566             :      */
    5567        1134 :     if (haveNonConst)
    5568             :     {
    5569          96 :         ArrayExpr  *arrayExpr = makeNode(ArrayExpr);
    5570             : 
    5571             :         /* array_collid will be set by parse_collate.c */
    5572          96 :         arrayExpr->element_typeid = coltype;
    5573          96 :         arrayExpr->array_typeid = arraytype;
    5574          96 :         arrayExpr->multidims = false;
    5575          96 :         arrayExpr->elements = exprs;
    5576          96 :         arrayExpr->location = -1;
    5577             : 
    5578          96 :         arrayNode = (Node *) arrayExpr;
    5579             :     }
    5580             :     else
    5581             :     {
    5582             :         int16       typlen;
    5583             :         bool        typbyval;
    5584             :         char        typalign;
    5585             :         Datum      *elems;
    5586             :         bool       *nulls;
    5587        1038 :         int         i = 0;
    5588             :         ArrayType  *arrayConst;
    5589        1038 :         int         dims[1] = {list_length(exprs)};
    5590        1038 :         int         lbs[1] = {1};
    5591             : 
    5592        1038 :         get_typlenbyvalalign(coltype, &typlen, &typbyval, &typalign);
    5593             : 
    5594        1038 :         elems = (Datum *) palloc(sizeof(Datum) * list_length(exprs));
    5595        1038 :         nulls = (bool *) palloc(sizeof(bool) * list_length(exprs));
    5596        4638 :         foreach_node(Const, value, exprs)
    5597             :         {
    5598        2562 :             elems[i] = value->constvalue;
    5599        2562 :             nulls[i++] = value->constisnull;
    5600             :         }
    5601             : 
    5602        1038 :         arrayConst = construct_md_array(elems, nulls, 1, dims, lbs,
    5603             :                                         coltype, typlen, typbyval, typalign);
    5604        1038 :         arrayNode = (Node *) makeConst(arraytype, -1, arraycollid,
    5605             :                                        -1, PointerGetDatum(arrayConst),
    5606             :                                        false, false);
    5607             : 
    5608        1038 :         pfree(elems);
    5609        1038 :         pfree(nulls);
    5610        1038 :         list_free(exprs);
    5611             :     }
    5612             : 
    5613             :     /* Build the SAOP expression node */
    5614        1134 :     saopexpr = makeNode(ScalarArrayOpExpr);
    5615        1134 :     saopexpr->opno = oper;
    5616        1134 :     saopexpr->opfuncid = get_opcode(oper);
    5617        1134 :     saopexpr->hashfuncid = InvalidOid;
    5618        1134 :     saopexpr->negfuncid = InvalidOid;
    5619        1134 :     saopexpr->useOr = true;
    5620        1134 :     saopexpr->inputcollid = inputcollid;
    5621        1134 :     saopexpr->args = list_make2(leftexpr, arrayNode);
    5622        1134 :     saopexpr->location = -1;
    5623             : 
    5624        1134 :     return saopexpr;
    5625             : }

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