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f94edb06ab60545a0e9e90aedc39e3b81b2b9e3f
postgres/src/backend/executor/execExpr.c
Tom Lane 16a56774fa Fix variable lifespan in ExecInitCoerceToDomain(). 
This undoes a mistake in 1ec7679f1: domainval and domainnull were
meant to live across loop iterations, but they were incorrectly
moved inside the loop.  The effect was only to emit useless extra
EEOP_MAKE_READONLY steps, so it's not a big deal; nonetheless,
back-patch to v13 where the mistake was introduced.

Ranier Vilela

Discussion: https://postgr.es/m/CAEudQAqXuhbkaAp-sGH6dR6Nsq7v28_0TPexHOm6FiDYqwQD-w@mail.gmail.com
2021-11-02 13:36:53 -04:00

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/*-------------------------------------------------------------------------
*
* execExpr.c
* Expression evaluation infrastructure.
*
* During executor startup, we compile each expression tree (which has
* previously been processed by the parser and planner) into an ExprState,
* using ExecInitExpr() et al. This converts the tree into a flat array
* of ExprEvalSteps, which may be thought of as instructions in a program.
* At runtime, we'll execute steps, starting with the first, until we reach
* an EEOP_DONE opcode.
*
* This file contains the "compilation" logic. It is independent of the
* specific execution technology we use (switch statement, computed goto,
* JIT compilation, etc).
*
* See src/backend/executor/README for some background, specifically the
* "Expression Trees and ExprState nodes", "Expression Initialization",
* and "Expression Evaluation" sections.
*
*
* Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
* src/backend/executor/execExpr.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "access/nbtree.h"
#include "catalog/objectaccess.h"
#include "catalog/pg_type.h"
#include "executor/execExpr.h"
#include "executor/nodeSubplan.h"
#include "funcapi.h"
#include "jit/jit.h"
#include "miscadmin.h"
#include "nodes/makefuncs.h"
#include "nodes/nodeFuncs.h"
#include "nodes/subscripting.h"
#include "optimizer/optimizer.h"
#include "pgstat.h"
#include "utils/acl.h"
#include "utils/array.h"
#include "utils/builtins.h"
#include "utils/datum.h"
#include "utils/lsyscache.h"
#include "utils/typcache.h"
typedef struct LastAttnumInfo
{
AttrNumber last_inner;
AttrNumber last_outer;
AttrNumber last_scan;
} LastAttnumInfo;
static void ExecReadyExpr(ExprState *state);
static void ExecInitExprRec(Expr *node, ExprState *state,
Datum *resv, bool *resnull);
static void ExecInitFunc(ExprEvalStep *scratch, Expr *node, List *args,
Oid funcid, Oid inputcollid,
ExprState *state);
static void ExecInitExprSlots(ExprState *state, Node *node);
static void ExecPushExprSlots(ExprState *state, LastAttnumInfo *info);
static bool get_last_attnums_walker(Node *node, LastAttnumInfo *info);
static bool ExecComputeSlotInfo(ExprState *state, ExprEvalStep *op);
static void ExecInitWholeRowVar(ExprEvalStep *scratch, Var *variable,
ExprState *state);
static void ExecInitSubscriptingRef(ExprEvalStep *scratch,
SubscriptingRef *sbsref,
ExprState *state,
Datum *resv, bool *resnull);
static bool isAssignmentIndirectionExpr(Expr *expr);
static void ExecInitCoerceToDomain(ExprEvalStep *scratch, CoerceToDomain *ctest,
ExprState *state,
Datum *resv, bool *resnull);
static void ExecBuildAggTransCall(ExprState *state, AggState *aggstate,
ExprEvalStep *scratch,
FunctionCallInfo fcinfo, AggStatePerTrans pertrans,
int transno, int setno, int setoff, bool ishash,
bool nullcheck);
/*
* ExecInitExpr: prepare an expression tree for execution
*
* This function builds and returns an ExprState implementing the given
* Expr node tree. The return ExprState can then be handed to ExecEvalExpr
* for execution. Because the Expr tree itself is read-only as far as
* ExecInitExpr and ExecEvalExpr are concerned, several different executions
* of the same plan tree can occur concurrently. (But note that an ExprState
* does mutate at runtime, so it can't be re-used concurrently.)
*
* This must be called in a memory context that will last as long as repeated
* executions of the expression are needed. Typically the context will be
* the same as the per-query context of the associated ExprContext.
*
* Any Aggref, WindowFunc, or SubPlan nodes found in the tree are added to
* the lists of such nodes held by the parent PlanState.
*
* Note: there is no ExecEndExpr function; we assume that any resource
* cleanup needed will be handled by just releasing the memory context
* in which the state tree is built. Functions that require additional
* cleanup work can register a shutdown callback in the ExprContext.
*
* 'node' is the root of the expression tree to compile.
* 'parent' is the PlanState node that owns the expression.
*
* 'parent' may be NULL if we are preparing an expression that is not
* associated with a plan tree. (If so, it can't have aggs or subplans.)
* Such cases should usually come through ExecPrepareExpr, not directly here.
*
* Also, if 'node' is NULL, we just return NULL. This is convenient for some
* callers that may or may not have an expression that needs to be compiled.
* Note that a NULL ExprState pointer *cannot* be handed to ExecEvalExpr,
* although ExecQual and ExecCheck will accept one (and treat it as "true").
*/
ExprState *
ExecInitExpr(Expr *node, PlanState *parent)
{
ExprState *state;
ExprEvalStep scratch = {0};
/* Special case: NULL expression produces a NULL ExprState pointer */
if (node == NULL)
return NULL;
/* Initialize ExprState with empty step list */
state = makeNode(ExprState);
state->expr = node;
state->parent = parent;
state->ext_params = NULL;
/* Insert EEOP_*_FETCHSOME steps as needed */
ExecInitExprSlots(state, (Node *) node);
/* Compile the expression proper */
ExecInitExprRec(node, state, &state->resvalue, &state->resnull);
/* Finally, append a DONE step */
scratch.opcode = EEOP_DONE;
ExprEvalPushStep(state, &scratch);
ExecReadyExpr(state);
return state;
}
/*
* ExecInitExprWithParams: prepare a standalone expression tree for execution
*
* This is the same as ExecInitExpr, except that there is no parent PlanState,
* and instead we may have a ParamListInfo describing PARAM_EXTERN Params.
*/
ExprState *
ExecInitExprWithParams(Expr *node, ParamListInfo ext_params)
{
ExprState *state;
ExprEvalStep scratch = {0};
/* Special case: NULL expression produces a NULL ExprState pointer */
if (node == NULL)
return NULL;
/* Initialize ExprState with empty step list */
state = makeNode(ExprState);
state->expr = node;
state->parent = NULL;
state->ext_params = ext_params;
/* Insert EEOP_*_FETCHSOME steps as needed */
ExecInitExprSlots(state, (Node *) node);
/* Compile the expression proper */
ExecInitExprRec(node, state, &state->resvalue, &state->resnull);
/* Finally, append a DONE step */
scratch.opcode = EEOP_DONE;
ExprEvalPushStep(state, &scratch);
ExecReadyExpr(state);
return state;
}
/*
* ExecInitQual: prepare a qual for execution by ExecQual
*
* Prepares for the evaluation of a conjunctive boolean expression (qual list
* with implicit AND semantics) that returns true if none of the
* subexpressions are false.
*
* We must return true if the list is empty. Since that's a very common case,
* we optimize it a bit further by translating to a NULL ExprState pointer
* rather than setting up an ExprState that computes constant TRUE. (Some
* especially hot-spot callers of ExecQual detect this and avoid calling
* ExecQual at all.)
*
* If any of the subexpressions yield NULL, then the result of the conjunction
* is false. This makes ExecQual primarily useful for evaluating WHERE
* clauses, since SQL specifies that tuples with null WHERE results do not
* get selected.
*/
ExprState *
ExecInitQual(List *qual, PlanState *parent)
{
ExprState *state;
ExprEvalStep scratch = {0};
List *adjust_jumps = NIL;
ListCell *lc;
/* short-circuit (here and in ExecQual) for empty restriction list */
if (qual == NIL)
return NULL;
Assert(IsA(qual, List));
state = makeNode(ExprState);
state->expr = (Expr *) qual;
state->parent = parent;
state->ext_params = NULL;
/* mark expression as to be used with ExecQual() */
state->flags = EEO_FLAG_IS_QUAL;
/* Insert EEOP_*_FETCHSOME steps as needed */
ExecInitExprSlots(state, (Node *) qual);
/*
* ExecQual() needs to return false for an expression returning NULL. That
* allows us to short-circuit the evaluation the first time a NULL is
* encountered. As qual evaluation is a hot-path this warrants using a
* special opcode for qual evaluation that's simpler than BOOL_AND (which
* has more complex NULL handling).
*/
scratch.opcode = EEOP_QUAL;
/*
* We can use ExprState's resvalue/resnull as target for each qual expr.
*/
scratch.resvalue = &state->resvalue;
scratch.resnull = &state->resnull;
foreach(lc, qual)
{
Expr *node = (Expr *) lfirst(lc);
/* first evaluate expression */
ExecInitExprRec(node, state, &state->resvalue, &state->resnull);
/* then emit EEOP_QUAL to detect if it's false (or null) */
scratch.d.qualexpr.jumpdone = -1;
ExprEvalPushStep(state, &scratch);
adjust_jumps = lappend_int(adjust_jumps,
state->steps_len - 1);
}
/* adjust jump targets */
foreach(lc, adjust_jumps)
{
ExprEvalStep *as = &state->steps[lfirst_int(lc)];
Assert(as->opcode == EEOP_QUAL);
Assert(as->d.qualexpr.jumpdone == -1);
as->d.qualexpr.jumpdone = state->steps_len;
}
/*
* At the end, we don't need to do anything more. The last qual expr must
* have yielded TRUE, and since its result is stored in the desired output
* location, we're done.
*/
scratch.opcode = EEOP_DONE;
ExprEvalPushStep(state, &scratch);
ExecReadyExpr(state);
return state;
}
/*
* ExecInitCheck: prepare a check constraint for execution by ExecCheck
*
* This is much like ExecInitQual/ExecQual, except that a null result from
* the conjunction is treated as TRUE. This behavior is appropriate for
* evaluating CHECK constraints, since SQL specifies that NULL constraint
* conditions are not failures.
*
* Note that like ExecInitQual, this expects input in implicit-AND format.
* Users of ExecCheck that have expressions in normal explicit-AND format
* can just apply ExecInitExpr to produce suitable input for ExecCheck.
*/
ExprState *
ExecInitCheck(List *qual, PlanState *parent)
{
/* short-circuit (here and in ExecCheck) for empty restriction list */
if (qual == NIL)
return NULL;
Assert(IsA(qual, List));
/*
* Just convert the implicit-AND list to an explicit AND (if there's more
* than one entry), and compile normally. Unlike ExecQual, we can't
* short-circuit on NULL results, so the regular AND behavior is needed.
*/
return ExecInitExpr(make_ands_explicit(qual), parent);
}
/*
* Call ExecInitExpr() on a list of expressions, return a list of ExprStates.
*/
List *
ExecInitExprList(List *nodes, PlanState *parent)
{
List *result = NIL;
ListCell *lc;
foreach(lc, nodes)
{
Expr *e = lfirst(lc);
result = lappend(result, ExecInitExpr(e, parent));
}
return result;
}
/*
* ExecBuildProjectionInfo
*
* Build a ProjectionInfo node for evaluating the given tlist in the given
* econtext, and storing the result into the tuple slot. (Caller must have
* ensured that tuple slot has a descriptor matching the tlist!)
*
* inputDesc can be NULL, but if it is not, we check to see whether simple
* Vars in the tlist match the descriptor. It is important to provide
* inputDesc for relation-scan plan nodes, as a cross check that the relation
* hasn't been changed since the plan was made. At higher levels of a plan,
* there is no need to recheck.
*
* This is implemented by internally building an ExprState that performs the
* whole projection in one go.
*
* Caution: before PG v10, the targetList was a list of ExprStates; now it
* should be the planner-created targetlist, since we do the compilation here.
*/
ProjectionInfo *
ExecBuildProjectionInfo(List *targetList,
ExprContext *econtext,
TupleTableSlot *slot,
PlanState *parent,
TupleDesc inputDesc)
{
ProjectionInfo *projInfo = makeNode(ProjectionInfo);
ExprState *state;
ExprEvalStep scratch = {0};
ListCell *lc;
projInfo->pi_exprContext = econtext;
/* We embed ExprState into ProjectionInfo instead of doing extra palloc */
projInfo->pi_state.tag = T_ExprState;
state = &projInfo->pi_state;
state->expr = (Expr *) targetList;
state->parent = parent;
state->ext_params = NULL;
state->resultslot = slot;
/* Insert EEOP_*_FETCHSOME steps as needed */
ExecInitExprSlots(state, (Node *) targetList);
/* Now compile each tlist column */
foreach(lc, targetList)
{
TargetEntry *tle = lfirst_node(TargetEntry, lc);
Var *variable = NULL;
AttrNumber attnum = 0;
bool isSafeVar = false;
/*
* If tlist expression is a safe non-system Var, use the fast-path
* ASSIGN_*_VAR opcodes. "Safe" means that we don't need to apply
* CheckVarSlotCompatibility() during plan startup. If a source slot
* was provided, we make the equivalent tests here; if a slot was not
* provided, we assume that no check is needed because we're dealing
* with a non-relation-scan-level expression.
*/
if (tle->expr != NULL &&
IsA(tle->expr, Var) &&
((Var *) tle->expr)->varattno > 0)
{
/* Non-system Var, but how safe is it? */
variable = (Var *) tle->expr;
attnum = variable->varattno;
if (inputDesc == NULL)
isSafeVar = true; /* can't check, just assume OK */
else if (attnum <= inputDesc->natts)
{
Form_pg_attribute attr = TupleDescAttr(inputDesc, attnum - 1);
/*
* If user attribute is dropped or has a type mismatch, don't
* use ASSIGN_*_VAR. Instead let the normal expression
* machinery handle it (which'll possibly error out).
*/
if (!attr->attisdropped && variable->vartype == attr->atttypid)
{
isSafeVar = true;
}
}
}
if (isSafeVar)
{
/* Fast-path: just generate an EEOP_ASSIGN_*_VAR step */
switch (variable->varno)
{
case INNER_VAR:
/* get the tuple from the inner node */
scratch.opcode = EEOP_ASSIGN_INNER_VAR;
break;
case OUTER_VAR:
/* get the tuple from the outer node */
scratch.opcode = EEOP_ASSIGN_OUTER_VAR;
break;
/* INDEX_VAR is handled by default case */
default:
/* get the tuple from the relation being scanned */
scratch.opcode = EEOP_ASSIGN_SCAN_VAR;
break;
}
scratch.d.assign_var.attnum = attnum - 1;
scratch.d.assign_var.resultnum = tle->resno - 1;
ExprEvalPushStep(state, &scratch);
}
else
{
/*
* Otherwise, compile the column expression normally.
*
* We can't tell the expression to evaluate directly into the
* result slot, as the result slot (and the exprstate for that
* matter) can change between executions. We instead evaluate
* into the ExprState's resvalue/resnull and then move.
*/
ExecInitExprRec(tle->expr, state,
&state->resvalue, &state->resnull);
/*
* Column might be referenced multiple times in upper nodes, so
* force value to R/O - but only if it could be an expanded datum.
*/
if (get_typlen(exprType((Node *) tle->expr)) == -1)
scratch.opcode = EEOP_ASSIGN_TMP_MAKE_RO;
else
scratch.opcode = EEOP_ASSIGN_TMP;
scratch.d.assign_tmp.resultnum = tle->resno - 1;
ExprEvalPushStep(state, &scratch);
}
}
scratch.opcode = EEOP_DONE;
ExprEvalPushStep(state, &scratch);
ExecReadyExpr(state);
return projInfo;
}
/*
* ExecBuildUpdateProjection
*
* Build a ProjectionInfo node for constructing a new tuple during UPDATE.
* The projection will be executed in the given econtext and the result will
* be stored into the given tuple slot. (Caller must have ensured that tuple
* slot has a descriptor matching the target rel!)
*
* When evalTargetList is false, targetList contains the UPDATE ... SET
* expressions that have already been computed by a subplan node; the values
* from this tlist are assumed to be available in the "outer" tuple slot.
* When evalTargetList is true, targetList contains the UPDATE ... SET
* expressions that must be computed (which could contain references to
* the outer, inner, or scan tuple slots).
*
* In either case, targetColnos contains a list of the target column numbers
* corresponding to the non-resjunk entries of targetList. The tlist values
* are assigned into these columns of the result tuple slot. Target columns
* not listed in targetColnos are filled from the UPDATE's old tuple, which
* is assumed to be available in the "scan" tuple slot.
*
* targetList can also contain resjunk columns. These must be evaluated
* if evalTargetList is true, but their values are discarded.
*
* relDesc must describe the relation we intend to update.
*
* This is basically a specialized variant of ExecBuildProjectionInfo.
* However, it also performs sanity checks equivalent to ExecCheckPlanOutput.
* Since we never make a normal tlist equivalent to the whole
* tuple-to-be-assigned, there is no convenient way to apply
* ExecCheckPlanOutput, so we must do our safety checks here.
*/
ProjectionInfo *
ExecBuildUpdateProjection(List *targetList,
bool evalTargetList,
List *targetColnos,
TupleDesc relDesc,
ExprContext *econtext,
TupleTableSlot *slot,
PlanState *parent)
{
ProjectionInfo *projInfo = makeNode(ProjectionInfo);
ExprState *state;
int nAssignableCols;
bool sawJunk;
Bitmapset *assignedCols;
LastAttnumInfo deform = {0, 0, 0};
ExprEvalStep scratch = {0};
int outerattnum;
ListCell *lc,
*lc2;
projInfo->pi_exprContext = econtext;
/* We embed ExprState into ProjectionInfo instead of doing extra palloc */
projInfo->pi_state.tag = T_ExprState;
state = &projInfo->pi_state;
if (evalTargetList)
state->expr = (Expr *) targetList;
else
state->expr = NULL; /* not used */
state->parent = parent;
state->ext_params = NULL;
state->resultslot = slot;
/*
* Examine the targetList to see how many non-junk columns there are, and
* to verify that the non-junk columns come before the junk ones.
*/
nAssignableCols = 0;
sawJunk = false;
foreach(lc, targetList)
{
TargetEntry *tle = lfirst_node(TargetEntry, lc);
if (tle->resjunk)
sawJunk = true;
else
{
if (sawJunk)
elog(ERROR, "subplan target list is out of order");
nAssignableCols++;
}
}
/* We should have one targetColnos entry per non-junk column */
if (nAssignableCols != list_length(targetColnos))
elog(ERROR, "targetColnos does not match subplan target list");
/*
* Build a bitmapset of the columns in targetColnos. (We could just use
* list_member_int() tests, but that risks O(N^2) behavior with many
* columns.)
*/
assignedCols = NULL;
foreach(lc, targetColnos)
{
AttrNumber targetattnum = lfirst_int(lc);
assignedCols = bms_add_member(assignedCols, targetattnum);
}
/*
* We need to insert EEOP_*_FETCHSOME steps to ensure the input tuples are
* sufficiently deconstructed. The scan tuple must be deconstructed at
* least as far as the last old column we need.
*/
for (int attnum = relDesc->natts; attnum > 0; attnum--)
{
Form_pg_attribute attr = TupleDescAttr(relDesc, attnum - 1);
if (attr->attisdropped)
continue;
if (bms_is_member(attnum, assignedCols))
continue;
deform.last_scan = attnum;
break;
}
/*
* If we're actually evaluating the tlist, incorporate its input
* requirements too; otherwise, we'll just need to fetch the appropriate
* number of columns of the "outer" tuple.
*/
if (evalTargetList)
get_last_attnums_walker((Node *) targetList, &deform);
else
deform.last_outer = nAssignableCols;
ExecPushExprSlots(state, &deform);
/*
* Now generate code to evaluate the tlist's assignable expressions or
* fetch them from the outer tuple, incidentally validating that they'll
* be of the right data type. The checks above ensure that the forboth()
* will iterate over exactly the non-junk columns.
*/
outerattnum = 0;
forboth(lc, targetList, lc2, targetColnos)
{
TargetEntry *tle = lfirst_node(TargetEntry, lc);
AttrNumber targetattnum = lfirst_int(lc2);
Form_pg_attribute attr;
Assert(!tle->resjunk);
/*
* Apply sanity checks comparable to ExecCheckPlanOutput().
*/
if (targetattnum <= 0 || targetattnum > relDesc->natts)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("table row type and query-specified row type do not match"),
errdetail("Query has too many columns.")));
attr = TupleDescAttr(relDesc, targetattnum - 1);
if (attr->attisdropped)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("table row type and query-specified row type do not match"),
errdetail("Query provides a value for a dropped column at ordinal position %d.",
targetattnum)));
if (exprType((Node *) tle->expr) != attr->atttypid)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("table row type and query-specified row type do not match"),
errdetail("Table has type %s at ordinal position %d, but query expects %s.",
format_type_be(attr->atttypid),
targetattnum,
format_type_be(exprType((Node *) tle->expr)))));
/* OK, generate code to perform the assignment. */
if (evalTargetList)
{
/*
* We must evaluate the TLE's expression and assign it. We do not
* bother jumping through hoops for "safe" Vars like
* ExecBuildProjectionInfo does; this is a relatively less-used
* path and it doesn't seem worth expending code for that.
*/
ExecInitExprRec(tle->expr, state,
&state->resvalue, &state->resnull);
/* Needn't worry about read-only-ness here, either. */
scratch.opcode = EEOP_ASSIGN_TMP;
scratch.d.assign_tmp.resultnum = targetattnum - 1;
ExprEvalPushStep(state, &scratch);
}
else
{
/* Just assign from the outer tuple. */
scratch.opcode = EEOP_ASSIGN_OUTER_VAR;
scratch.d.assign_var.attnum = outerattnum;
scratch.d.assign_var.resultnum = targetattnum - 1;
ExprEvalPushStep(state, &scratch);
}
outerattnum++;
}
/*
* If we're evaluating the tlist, must evaluate any resjunk columns too.
* (This matters for things like MULTIEXPR_SUBLINK SubPlans.)
*/
if (evalTargetList)
{
for_each_cell(lc, targetList, lc)
{
TargetEntry *tle = lfirst_node(TargetEntry, lc);
Assert(tle->resjunk);
ExecInitExprRec(tle->expr, state,
&state->resvalue, &state->resnull);
}
}
/*
* Now generate code to copy over any old columns that were not assigned
* to, and to ensure that dropped columns are set to NULL.
*/
for (int attnum = 1; attnum <= relDesc->natts; attnum++)
{
Form_pg_attribute attr = TupleDescAttr(relDesc, attnum - 1);
if (attr->attisdropped)
{
/* Put a null into the ExprState's resvalue/resnull ... */
scratch.opcode = EEOP_CONST;
scratch.resvalue = &state->resvalue;
scratch.resnull = &state->resnull;
scratch.d.constval.value = (Datum) 0;
scratch.d.constval.isnull = true;
ExprEvalPushStep(state, &scratch);
/* ... then assign it to the result slot */
scratch.opcode = EEOP_ASSIGN_TMP;
scratch.d.assign_tmp.resultnum = attnum - 1;
ExprEvalPushStep(state, &scratch);
}
else if (!bms_is_member(attnum, assignedCols))
{
/* Certainly the right type, so needn't check */
scratch.opcode = EEOP_ASSIGN_SCAN_VAR;
scratch.d.assign_var.attnum = attnum - 1;
scratch.d.assign_var.resultnum = attnum - 1;
ExprEvalPushStep(state, &scratch);
}
}
scratch.opcode = EEOP_DONE;
ExprEvalPushStep(state, &scratch);
ExecReadyExpr(state);
return projInfo;
}
/*
* ExecPrepareExpr --- initialize for expression execution outside a normal
* Plan tree context.
*
* This differs from ExecInitExpr in that we don't assume the caller is
* already running in the EState's per-query context. Also, we run the
* passed expression tree through expression_planner() to prepare it for
* execution. (In ordinary Plan trees the regular planning process will have
* made the appropriate transformations on expressions, but for standalone
* expressions this won't have happened.)
*/
ExprState *
ExecPrepareExpr(Expr *node, EState *estate)
{
ExprState *result;
MemoryContext oldcontext;
oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
node = expression_planner(node);
result = ExecInitExpr(node, NULL);
MemoryContextSwitchTo(oldcontext);
return result;
}
/*
* ExecPrepareQual --- initialize for qual execution outside a normal
* Plan tree context.
*
* This differs from ExecInitQual in that we don't assume the caller is
* already running in the EState's per-query context. Also, we run the
* passed expression tree through expression_planner() to prepare it for
* execution. (In ordinary Plan trees the regular planning process will have
* made the appropriate transformations on expressions, but for standalone
* expressions this won't have happened.)
*/
ExprState *
ExecPrepareQual(List *qual, EState *estate)
{
ExprState *result;
MemoryContext oldcontext;
oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
qual = (List *) expression_planner((Expr *) qual);
result = ExecInitQual(qual, NULL);
MemoryContextSwitchTo(oldcontext);
return result;
}
/*
* ExecPrepareCheck -- initialize check constraint for execution outside a
* normal Plan tree context.
*
* See ExecPrepareExpr() and ExecInitCheck() for details.
*/
ExprState *
ExecPrepareCheck(List *qual, EState *estate)
{
ExprState *result;
MemoryContext oldcontext;
oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
qual = (List *) expression_planner((Expr *) qual);
result = ExecInitCheck(qual, NULL);
MemoryContextSwitchTo(oldcontext);
return result;
}
/*
* Call ExecPrepareExpr() on each member of a list of Exprs, and return
* a list of ExprStates.
*
* See ExecPrepareExpr() for details.
*/
List *
ExecPrepareExprList(List *nodes, EState *estate)
{
List *result = NIL;
MemoryContext oldcontext;
ListCell *lc;
/* Ensure that the list cell nodes are in the right context too */
oldcontext = MemoryContextSwitchTo(estate->es_query_cxt);
foreach(lc, nodes)
{
Expr *e = (Expr *) lfirst(lc);
result = lappend(result, ExecPrepareExpr(e, estate));
}
MemoryContextSwitchTo(oldcontext);
return result;
}
/*
* ExecCheck - evaluate a check constraint
*
* For check constraints, a null result is taken as TRUE, ie the constraint
* passes.
*
* The check constraint may have been prepared with ExecInitCheck
* (possibly via ExecPrepareCheck) if the caller had it in implicit-AND
* format, but a regular boolean expression prepared with ExecInitExpr or
* ExecPrepareExpr works too.
*/
bool
ExecCheck(ExprState *state, ExprContext *econtext)
{
Datum ret;
bool isnull;
/* short-circuit (here and in ExecInitCheck) for empty restriction list */
if (state == NULL)
return true;
/* verify that expression was not compiled using ExecInitQual */
Assert(!(state->flags & EEO_FLAG_IS_QUAL));
ret = ExecEvalExprSwitchContext(state, econtext, &isnull);
if (isnull)
return true;
return DatumGetBool(ret);
}
/*
* Prepare a compiled expression for execution. This has to be called for
* every ExprState before it can be executed.
*
* NB: While this currently only calls ExecReadyInterpretedExpr(),
* this will likely get extended to further expression evaluation methods.
* Therefore this should be used instead of directly calling
* ExecReadyInterpretedExpr().
*/
static void
ExecReadyExpr(ExprState *state)
{
if (jit_compile_expr(state))
return;
ExecReadyInterpretedExpr(state);
}
/*
* Append the steps necessary for the evaluation of node to ExprState->steps,
* possibly recursing into sub-expressions of node.
*
* node - expression to evaluate
* state - ExprState to whose ->steps to append the necessary operations
* resv / resnull - where to store the result of the node into
*/
static void
ExecInitExprRec(Expr *node, ExprState *state,
Datum *resv, bool *resnull)
{
ExprEvalStep scratch = {0};
/* Guard against stack overflow due to overly complex expressions */
check_stack_depth();
/* Step's output location is always what the caller gave us */
Assert(resv != NULL && resnull != NULL);
scratch.resvalue = resv;
scratch.resnull = resnull;
/* cases should be ordered as they are in enum NodeTag */
switch (nodeTag(node))
{
case T_Var:
{
Var *variable = (Var *) node;
if (variable->varattno == InvalidAttrNumber)
{
/* whole-row Var */
ExecInitWholeRowVar(&scratch, variable, state);
}
else if (variable->varattno <= 0)
{
/* system column */
scratch.d.var.attnum = variable->varattno;
scratch.d.var.vartype = variable->vartype;
switch (variable->varno)
{
case INNER_VAR:
scratch.opcode = EEOP_INNER_SYSVAR;
break;
case OUTER_VAR:
scratch.opcode = EEOP_OUTER_SYSVAR;
break;
/* INDEX_VAR is handled by default case */
default:
scratch.opcode = EEOP_SCAN_SYSVAR;
break;
}
}
else
{
/* regular user column */
scratch.d.var.attnum = variable->varattno - 1;
scratch.d.var.vartype = variable->vartype;
switch (variable->varno)
{
case INNER_VAR:
scratch.opcode = EEOP_INNER_VAR;
break;
case OUTER_VAR:
scratch.opcode = EEOP_OUTER_VAR;
break;
/* INDEX_VAR is handled by default case */
default:
scratch.opcode = EEOP_SCAN_VAR;
break;
}
}
ExprEvalPushStep(state, &scratch);
break;
}
case T_Const:
{
Const *con = (Const *) node;
scratch.opcode = EEOP_CONST;
scratch.d.constval.value = con->constvalue;
scratch.d.constval.isnull = con->constisnull;
ExprEvalPushStep(state, &scratch);
break;
}
case T_Param:
{
Param *param = (Param *) node;
ParamListInfo params;
switch (param->paramkind)
{
case PARAM_EXEC:
scratch.opcode = EEOP_PARAM_EXEC;
scratch.d.param.paramid = param->paramid;
scratch.d.param.paramtype = param->paramtype;
ExprEvalPushStep(state, &scratch);
break;
case PARAM_EXTERN:
/*
* If we have a relevant ParamCompileHook, use it;
* otherwise compile a standard EEOP_PARAM_EXTERN
* step. ext_params, if supplied, takes precedence
* over info from the parent node's EState (if any).
*/
if (state->ext_params)
params = state->ext_params;
else if (state->parent &&
state->parent->state)
params = state->parent->state->es_param_list_info;
else
params = NULL;
if (params && params->paramCompile)
{
params->paramCompile(params, param, state,
resv, resnull);
}
else
{
scratch.opcode = EEOP_PARAM_EXTERN;
scratch.d.param.paramid = param->paramid;
scratch.d.param.paramtype = param->paramtype;
ExprEvalPushStep(state, &scratch);
}
break;
default:
elog(ERROR, "unrecognized paramkind: %d",
(int) param->paramkind);
break;
}
break;
}
case T_Aggref:
{
Aggref *aggref = (Aggref *) node;
scratch.opcode = EEOP_AGGREF;
scratch.d.aggref.aggno = aggref->aggno;
if (state->parent && IsA(state->parent, AggState))
{
AggState *aggstate = (AggState *) state->parent;
aggstate->aggs = lappend(aggstate->aggs, aggref);
}
else
{
/* planner messed up */
elog(ERROR, "Aggref found in non-Agg plan node");
}
ExprEvalPushStep(state, &scratch);
break;
}
case T_GroupingFunc:
{
GroupingFunc *grp_node = (GroupingFunc *) node;
Agg *agg;
if (!state->parent || !IsA(state->parent, AggState) ||
!IsA(state->parent->plan, Agg))
elog(ERROR, "GroupingFunc found in non-Agg plan node");
scratch.opcode = EEOP_GROUPING_FUNC;
agg = (Agg *) (state->parent->plan);
if (agg->groupingSets)
scratch.d.grouping_func.clauses = grp_node->cols;
else
scratch.d.grouping_func.clauses = NIL;
ExprEvalPushStep(state, &scratch);
break;
}
case T_WindowFunc:
{
WindowFunc *wfunc = (WindowFunc *) node;
WindowFuncExprState *wfstate = makeNode(WindowFuncExprState);
wfstate->wfunc = wfunc;
if (state->parent && IsA(state->parent, WindowAggState))
{
WindowAggState *winstate = (WindowAggState *) state->parent;
int nfuncs;
winstate->funcs = lappend(winstate->funcs, wfstate);
nfuncs = ++winstate->numfuncs;
if (wfunc->winagg)
winstate->numaggs++;
/* for now initialize agg using old style expressions */
wfstate->args = ExecInitExprList(wfunc->args,
state->parent);
wfstate->aggfilter = ExecInitExpr(wfunc->aggfilter,
state->parent);
/*
* Complain if the windowfunc's arguments contain any
* windowfuncs; nested window functions are semantically
* nonsensical. (This should have been caught earlier,
* but we defend against it here anyway.)
*/
if (nfuncs != winstate->numfuncs)
ereport(ERROR,
(errcode(ERRCODE_WINDOWING_ERROR),
errmsg("window function calls cannot be nested")));
}
else
{
/* planner messed up */
elog(ERROR, "WindowFunc found in non-WindowAgg plan node");
}
scratch.opcode = EEOP_WINDOW_FUNC;
scratch.d.window_func.wfstate = wfstate;
ExprEvalPushStep(state, &scratch);
break;
}
case T_SubscriptingRef:
{
SubscriptingRef *sbsref = (SubscriptingRef *) node;
ExecInitSubscriptingRef(&scratch, sbsref, state, resv, resnull);
break;
}
case T_FuncExpr:
{
FuncExpr *func = (FuncExpr *) node;
ExecInitFunc(&scratch, node,
func->args, func->funcid, func->inputcollid,
state);
ExprEvalPushStep(state, &scratch);
break;
}
case T_OpExpr:
{
OpExpr *op = (OpExpr *) node;
ExecInitFunc(&scratch, node,
op->args, op->opfuncid, op->inputcollid,
state);
ExprEvalPushStep(state, &scratch);
break;
}
case T_DistinctExpr:
{
DistinctExpr *op = (DistinctExpr *) node;
ExecInitFunc(&scratch, node,
op->args, op->opfuncid, op->inputcollid,
state);
/*
* Change opcode of call instruction to EEOP_DISTINCT.
*
* XXX: historically we've not called the function usage
* pgstat infrastructure - that seems inconsistent given that
* we do so for normal function *and* operator evaluation. If
* we decided to do that here, we'd probably want separate
* opcodes for FUSAGE or not.
*/
scratch.opcode = EEOP_DISTINCT;
ExprEvalPushStep(state, &scratch);
break;
}
case T_NullIfExpr:
{
NullIfExpr *op = (NullIfExpr *) node;
ExecInitFunc(&scratch, node,
op->args, op->opfuncid, op->inputcollid,
state);
/*
* Change opcode of call instruction to EEOP_NULLIF.
*
* XXX: historically we've not called the function usage
* pgstat infrastructure - that seems inconsistent given that
* we do so for normal function *and* operator evaluation. If
* we decided to do that here, we'd probably want separate
* opcodes for FUSAGE or not.
*/
scratch.opcode = EEOP_NULLIF;
ExprEvalPushStep(state, &scratch);
break;
}
case T_ScalarArrayOpExpr:
{
ScalarArrayOpExpr *opexpr = (ScalarArrayOpExpr *) node;
Expr *scalararg;
Expr *arrayarg;
FmgrInfo *finfo;
FunctionCallInfo fcinfo;
AclResult aclresult;
FmgrInfo *hash_finfo;
FunctionCallInfo hash_fcinfo;
Assert(list_length(opexpr->args) == 2);
scalararg = (Expr *) linitial(opexpr->args);
arrayarg = (Expr *) lsecond(opexpr->args);
/* Check permission to call function */
aclresult = pg_proc_aclcheck(opexpr->opfuncid,
GetUserId(),
ACL_EXECUTE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, OBJECT_FUNCTION,
get_func_name(opexpr->opfuncid));
InvokeFunctionExecuteHook(opexpr->opfuncid);
if (OidIsValid(opexpr->hashfuncid))
{
aclresult = pg_proc_aclcheck(opexpr->hashfuncid,
GetUserId(),
ACL_EXECUTE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, OBJECT_FUNCTION,
get_func_name(opexpr->hashfuncid));
InvokeFunctionExecuteHook(opexpr->hashfuncid);
}
/* Set up the primary fmgr lookup information */
finfo = palloc0(sizeof(FmgrInfo));
fcinfo = palloc0(SizeForFunctionCallInfo(2));
fmgr_info(opexpr->opfuncid, finfo);
fmgr_info_set_expr((Node *) node, finfo);
InitFunctionCallInfoData(*fcinfo, finfo, 2,
opexpr->inputcollid, NULL, NULL);
/*
* If hashfuncid is set, we create a EEOP_HASHED_SCALARARRAYOP
* step instead of a EEOP_SCALARARRAYOP. This provides much
* faster lookup performance than the normal linear search
* when the number of items in the array is anything but very
* small.
*/
if (OidIsValid(opexpr->hashfuncid))
{
hash_finfo = palloc0(sizeof(FmgrInfo));
hash_fcinfo = palloc0(SizeForFunctionCallInfo(1));
fmgr_info(opexpr->hashfuncid, hash_finfo);
fmgr_info_set_expr((Node *) node, hash_finfo);
InitFunctionCallInfoData(*hash_fcinfo, hash_finfo,
1, opexpr->inputcollid, NULL,
NULL);
scratch.d.hashedscalararrayop.hash_finfo = hash_finfo;
scratch.d.hashedscalararrayop.hash_fcinfo_data = hash_fcinfo;
scratch.d.hashedscalararrayop.hash_fn_addr = hash_finfo->fn_addr;
/* Evaluate scalar directly into left function argument */
ExecInitExprRec(scalararg, state,
&fcinfo->args[0].value, &fcinfo->args[0].isnull);
/*
* Evaluate array argument into our return value. There's
* no danger in that, because the return value is
* guaranteed to be overwritten by
* EEOP_HASHED_SCALARARRAYOP, and will not be passed to
* any other expression.
*/
ExecInitExprRec(arrayarg, state, resv, resnull);
/* And perform the operation */
scratch.opcode = EEOP_HASHED_SCALARARRAYOP;
scratch.d.hashedscalararrayop.finfo = finfo;
scratch.d.hashedscalararrayop.fcinfo_data = fcinfo;
scratch.d.hashedscalararrayop.fn_addr = finfo->fn_addr;
scratch.d.hashedscalararrayop.hash_finfo = hash_finfo;
scratch.d.hashedscalararrayop.hash_fcinfo_data = hash_fcinfo;
scratch.d.hashedscalararrayop.hash_fn_addr = hash_finfo->fn_addr;
ExprEvalPushStep(state, &scratch);
}
else
{
/* Evaluate scalar directly into left function argument */
ExecInitExprRec(scalararg, state,
&fcinfo->args[0].value,
&fcinfo->args[0].isnull);
/*
* Evaluate array argument into our return value. There's
* no danger in that, because the return value is
* guaranteed to be overwritten by EEOP_SCALARARRAYOP, and
* will not be passed to any other expression.
*/
ExecInitExprRec(arrayarg, state, resv, resnull);
/* And perform the operation */
scratch.opcode = EEOP_SCALARARRAYOP;
scratch.d.scalararrayop.element_type = InvalidOid;
scratch.d.scalararrayop.useOr = opexpr->useOr;
scratch.d.scalararrayop.finfo = finfo;
scratch.d.scalararrayop.fcinfo_data = fcinfo;
scratch.d.scalararrayop.fn_addr = finfo->fn_addr;
ExprEvalPushStep(state, &scratch);
}
break;
}
case T_BoolExpr:
{
BoolExpr *boolexpr = (BoolExpr *) node;
int nargs = list_length(boolexpr->args);
List *adjust_jumps = NIL;
int off;
ListCell *lc;
/* allocate scratch memory used by all steps of AND/OR */
if (boolexpr->boolop != NOT_EXPR)
scratch.d.boolexpr.anynull = (bool *) palloc(sizeof(bool));
/*
* For each argument evaluate the argument itself, then
* perform the bool operation's appropriate handling.
*
* We can evaluate each argument into our result area, since
* the short-circuiting logic means we only need to remember
* previous NULL values.
*
* AND/OR is split into separate STEP_FIRST (one) / STEP (zero
* or more) / STEP_LAST (one) steps, as each of those has to
* perform different work. The FIRST/LAST split is valid
* because AND/OR have at least two arguments.
*/
off = 0;
foreach(lc, boolexpr->args)
{
Expr *arg = (Expr *) lfirst(lc);
/* Evaluate argument into our output variable */
ExecInitExprRec(arg, state, resv, resnull);
/* Perform the appropriate step type */
switch (boolexpr->boolop)
{
case AND_EXPR:
Assert(nargs >= 2);
if (off == 0)
scratch.opcode = EEOP_BOOL_AND_STEP_FIRST;
else if (off + 1 == nargs)
scratch.opcode = EEOP_BOOL_AND_STEP_LAST;
else
scratch.opcode = EEOP_BOOL_AND_STEP;
break;
case OR_EXPR:
Assert(nargs >= 2);
if (off == 0)
scratch.opcode = EEOP_BOOL_OR_STEP_FIRST;
else if (off + 1 == nargs)
scratch.opcode = EEOP_BOOL_OR_STEP_LAST;
else
scratch.opcode = EEOP_BOOL_OR_STEP;
break;
case NOT_EXPR:
Assert(nargs == 1);
scratch.opcode = EEOP_BOOL_NOT_STEP;
break;
default:
elog(ERROR, "unrecognized boolop: %d",
(int) boolexpr->boolop);
break;
}
scratch.d.boolexpr.jumpdone = -1;
ExprEvalPushStep(state, &scratch);
adjust_jumps = lappend_int(adjust_jumps,
state->steps_len - 1);
off++;
}
/* adjust jump targets */
foreach(lc, adjust_jumps)
{
ExprEvalStep *as = &state->steps[lfirst_int(lc)];
Assert(as->d.boolexpr.jumpdone == -1);
as->d.boolexpr.jumpdone = state->steps_len;
}
break;
}
case T_SubPlan:
{
SubPlan *subplan = (SubPlan *) node;
SubPlanState *sstate;
if (!state->parent)
elog(ERROR, "SubPlan found with no parent plan");
sstate = ExecInitSubPlan(subplan, state->parent);
/* add SubPlanState nodes to state->parent->subPlan */
state->parent->subPlan = lappend(state->parent->subPlan,
sstate);
scratch.opcode = EEOP_SUBPLAN;
scratch.d.subplan.sstate = sstate;
ExprEvalPushStep(state, &scratch);
break;
}
case T_FieldSelect:
{
FieldSelect *fselect = (FieldSelect *) node;
/* evaluate row/record argument into result area */
ExecInitExprRec(fselect->arg, state, resv, resnull);
/* and extract field */
scratch.opcode = EEOP_FIELDSELECT;
scratch.d.fieldselect.fieldnum = fselect->fieldnum;
scratch.d.fieldselect.resulttype = fselect->resulttype;
scratch.d.fieldselect.rowcache.cacheptr = NULL;
ExprEvalPushStep(state, &scratch);
break;
}
case T_FieldStore:
{
FieldStore *fstore = (FieldStore *) node;
TupleDesc tupDesc;
ExprEvalRowtypeCache *rowcachep;
Datum *values;
bool *nulls;
int ncolumns;
ListCell *l1,
*l2;
/* find out the number of columns in the composite type */
tupDesc = lookup_rowtype_tupdesc(fstore->resulttype, -1);
ncolumns = tupDesc->natts;
DecrTupleDescRefCount(tupDesc);
/* create workspace for column values */
values = (Datum *) palloc(sizeof(Datum) * ncolumns);
nulls = (bool *) palloc(sizeof(bool) * ncolumns);
/* create shared composite-type-lookup cache struct */
rowcachep = palloc(sizeof(ExprEvalRowtypeCache));
rowcachep->cacheptr = NULL;
/* emit code to evaluate the composite input value */
ExecInitExprRec(fstore->arg, state, resv, resnull);
/* next, deform the input tuple into our workspace */
scratch.opcode = EEOP_FIELDSTORE_DEFORM;
scratch.d.fieldstore.fstore = fstore;
scratch.d.fieldstore.rowcache = rowcachep;
scratch.d.fieldstore.values = values;
scratch.d.fieldstore.nulls = nulls;
scratch.d.fieldstore.ncolumns = ncolumns;
ExprEvalPushStep(state, &scratch);
/* evaluate new field values, store in workspace columns */
forboth(l1, fstore->newvals, l2, fstore->fieldnums)
{
Expr *e = (Expr *) lfirst(l1);
AttrNumber fieldnum = lfirst_int(l2);
Datum *save_innermost_caseval;
bool *save_innermost_casenull;
if (fieldnum <= 0 || fieldnum > ncolumns)
elog(ERROR, "field number %d is out of range in FieldStore",
fieldnum);
/*
* Use the CaseTestExpr mechanism to pass down the old
* value of the field being replaced; this is needed in
* case the newval is itself a FieldStore or
* SubscriptingRef that has to obtain and modify the old
* value. It's safe to reuse the CASE mechanism because
* there cannot be a CASE between here and where the value
* would be needed, and a field assignment can't be within
* a CASE either. (So saving and restoring
* innermost_caseval is just paranoia, but let's do it
* anyway.)
*
* Another non-obvious point is that it's safe to use the
* field's values[]/nulls[] entries as both the caseval
* source and the result address for this subexpression.
* That's okay only because (1) both FieldStore and
* SubscriptingRef evaluate their arg or refexpr inputs
* first, and (2) any such CaseTestExpr is directly the
* arg or refexpr input. So any read of the caseval will
* occur before there's a chance to overwrite it. Also,
* if multiple entries in the newvals/fieldnums lists
* target the same field, they'll effectively be applied
* left-to-right which is what we want.
*/
save_innermost_caseval = state->innermost_caseval;
save_innermost_casenull = state->innermost_casenull;
state->innermost_caseval = &values[fieldnum - 1];
state->innermost_casenull = &nulls[fieldnum - 1];
ExecInitExprRec(e, state,
&values[fieldnum - 1],
&nulls[fieldnum - 1]);
state->innermost_caseval = save_innermost_caseval;
state->innermost_casenull = save_innermost_casenull;
}
/* finally, form result tuple */
scratch.opcode = EEOP_FIELDSTORE_FORM;
scratch.d.fieldstore.fstore = fstore;
scratch.d.fieldstore.rowcache = rowcachep;
scratch.d.fieldstore.values = values;
scratch.d.fieldstore.nulls = nulls;
scratch.d.fieldstore.ncolumns = ncolumns;
ExprEvalPushStep(state, &scratch);
break;
}
case T_RelabelType:
{
/* relabel doesn't need to do anything at runtime */
RelabelType *relabel = (RelabelType *) node;
ExecInitExprRec(relabel->arg, state, resv, resnull);
break;
}
case T_CoerceViaIO:
{
CoerceViaIO *iocoerce = (CoerceViaIO *) node;
Oid iofunc;
bool typisvarlena;
Oid typioparam;
FunctionCallInfo fcinfo_in;
/* evaluate argument into step's result area */
ExecInitExprRec(iocoerce->arg, state, resv, resnull);
/*
* Prepare both output and input function calls, to be
* evaluated inside a single evaluation step for speed - this
* can be a very common operation.
*
* We don't check permissions here as a type's input/output
* function are assumed to be executable by everyone.
*/
scratch.opcode = EEOP_IOCOERCE;
/* lookup the source type's output function */
scratch.d.iocoerce.finfo_out = palloc0(sizeof(FmgrInfo));
scratch.d.iocoerce.fcinfo_data_out = palloc0(SizeForFunctionCallInfo(1));
getTypeOutputInfo(exprType((Node *) iocoerce->arg),
&iofunc, &typisvarlena);
fmgr_info(iofunc, scratch.d.iocoerce.finfo_out);
fmgr_info_set_expr((Node *) node, scratch.d.iocoerce.finfo_out);
InitFunctionCallInfoData(*scratch.d.iocoerce.fcinfo_data_out,
scratch.d.iocoerce.finfo_out,
1, InvalidOid, NULL, NULL);
/* lookup the result type's input function */
scratch.d.iocoerce.finfo_in = palloc0(sizeof(FmgrInfo));
scratch.d.iocoerce.fcinfo_data_in = palloc0(SizeForFunctionCallInfo(3));
getTypeInputInfo(iocoerce->resulttype,
&iofunc, &typioparam);
fmgr_info(iofunc, scratch.d.iocoerce.finfo_in);
fmgr_info_set_expr((Node *) node, scratch.d.iocoerce.finfo_in);
InitFunctionCallInfoData(*scratch.d.iocoerce.fcinfo_data_in,
scratch.d.iocoerce.finfo_in,
3, InvalidOid, NULL, NULL);
/*
* We can preload the second and third arguments for the input
* function, since they're constants.
*/
fcinfo_in = scratch.d.iocoerce.fcinfo_data_in;
fcinfo_in->args[1].value = ObjectIdGetDatum(typioparam);
fcinfo_in->args[1].isnull = false;
fcinfo_in->args[2].value = Int32GetDatum(-1);
fcinfo_in->args[2].isnull = false;
ExprEvalPushStep(state, &scratch);
break;
}
case T_ArrayCoerceExpr:
{
ArrayCoerceExpr *acoerce = (ArrayCoerceExpr *) node;
Oid resultelemtype;
ExprState *elemstate;
/* evaluate argument into step's result area */
ExecInitExprRec(acoerce->arg, state, resv, resnull);
resultelemtype = get_element_type(acoerce->resulttype);
if (!OidIsValid(resultelemtype))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("target type is not an array")));
/*
* Construct a sub-expression for the per-element expression;
* but don't ready it until after we check it for triviality.
* We assume it hasn't any Var references, but does have a
* CaseTestExpr representing the source array element values.
*/
elemstate = makeNode(ExprState);
elemstate->expr = acoerce->elemexpr;
elemstate->parent = state->parent;
elemstate->ext_params = state->ext_params;
elemstate->innermost_caseval = (Datum *) palloc(sizeof(Datum));
elemstate->innermost_casenull = (bool *) palloc(sizeof(bool));
ExecInitExprRec(acoerce->elemexpr, elemstate,
&elemstate->resvalue, &elemstate->resnull);
if (elemstate->steps_len == 1 &&
elemstate->steps[0].opcode == EEOP_CASE_TESTVAL)
{
/* Trivial, so we need no per-element work at runtime */
elemstate = NULL;
}
else
{
/* Not trivial, so append a DONE step */
scratch.opcode = EEOP_DONE;
ExprEvalPushStep(elemstate, &scratch);
/* and ready the subexpression */
ExecReadyExpr(elemstate);
}
scratch.opcode = EEOP_ARRAYCOERCE;
scratch.d.arraycoerce.elemexprstate = elemstate;
scratch.d.arraycoerce.resultelemtype = resultelemtype;
if (elemstate)
{
/* Set up workspace for array_map */
scratch.d.arraycoerce.amstate =
(ArrayMapState *) palloc0(sizeof(ArrayMapState));
}
else
{
/* Don't need workspace if there's no subexpression */
scratch.d.arraycoerce.amstate = NULL;
}
ExprEvalPushStep(state, &scratch);
break;
}
case T_ConvertRowtypeExpr:
{
ConvertRowtypeExpr *convert = (ConvertRowtypeExpr *) node;
ExprEvalRowtypeCache *rowcachep;
/* cache structs must be out-of-line for space reasons */
rowcachep = palloc(2 * sizeof(ExprEvalRowtypeCache));
rowcachep[0].cacheptr = NULL;
rowcachep[1].cacheptr = NULL;
/* evaluate argument into step's result area */
ExecInitExprRec(convert->arg, state, resv, resnull);
/* and push conversion step */
scratch.opcode = EEOP_CONVERT_ROWTYPE;
scratch.d.convert_rowtype.inputtype =
exprType((Node *) convert->arg);
scratch.d.convert_rowtype.outputtype = convert->resulttype;
scratch.d.convert_rowtype.incache = &rowcachep[0];
scratch.d.convert_rowtype.outcache = &rowcachep[1];
scratch.d.convert_rowtype.map = NULL;
ExprEvalPushStep(state, &scratch);
break;
}
/* note that CaseWhen expressions are handled within this block */
case T_CaseExpr:
{
CaseExpr *caseExpr = (CaseExpr *) node;
List *adjust_jumps = NIL;
Datum *caseval = NULL;
bool *casenull = NULL;
ListCell *lc;
/*
* If there's a test expression, we have to evaluate it and
* save the value where the CaseTestExpr placeholders can find
* it.
*/
if (caseExpr->arg != NULL)
{
/* Evaluate testexpr into caseval/casenull workspace */
caseval = palloc(sizeof(Datum));
casenull = palloc(sizeof(bool));
ExecInitExprRec(caseExpr->arg, state,
caseval, casenull);
/*
* Since value might be read multiple times, force to R/O
* - but only if it could be an expanded datum.
*/
if (get_typlen(exprType((Node *) caseExpr->arg)) == -1)
{
/* change caseval in-place */
scratch.opcode = EEOP_MAKE_READONLY;
scratch.resvalue = caseval;
scratch.resnull = casenull;
scratch.d.make_readonly.value = caseval;
scratch.d.make_readonly.isnull = casenull;
ExprEvalPushStep(state, &scratch);
/* restore normal settings of scratch fields */
scratch.resvalue = resv;
scratch.resnull = resnull;
}
}
/*
* Prepare to evaluate each of the WHEN clauses in turn; as
* soon as one is true we return the value of the
* corresponding THEN clause. If none are true then we return
* the value of the ELSE clause, or NULL if there is none.
*/
foreach(lc, caseExpr->args)
{
CaseWhen *when = (CaseWhen *) lfirst(lc);
Datum *save_innermost_caseval;
bool *save_innermost_casenull;
int whenstep;
/*
* Make testexpr result available to CaseTestExpr nodes
* within the condition. We must save and restore prior
* setting of innermost_caseval fields, in case this node
* is itself within a larger CASE.
*
* If there's no test expression, we don't actually need
* to save and restore these fields; but it's less code to
* just do so unconditionally.
*/
save_innermost_caseval = state->innermost_caseval;
save_innermost_casenull = state->innermost_casenull;
state->innermost_caseval = caseval;
state->innermost_casenull = casenull;
/* evaluate condition into CASE's result variables */
ExecInitExprRec(when->expr, state, resv, resnull);
state->innermost_caseval = save_innermost_caseval;
state->innermost_casenull = save_innermost_casenull;
/* If WHEN result isn't true, jump to next CASE arm */
scratch.opcode = EEOP_JUMP_IF_NOT_TRUE;
scratch.d.jump.jumpdone = -1; /* computed later */
ExprEvalPushStep(state, &scratch);
whenstep = state->steps_len - 1;
/*
* If WHEN result is true, evaluate THEN result, storing
* it into the CASE's result variables.
*/
ExecInitExprRec(when->result, state, resv, resnull);
/* Emit JUMP step to jump to end of CASE's code */
scratch.opcode = EEOP_JUMP;
scratch.d.jump.jumpdone = -1; /* computed later */
ExprEvalPushStep(state, &scratch);
/*
* Don't know address for that jump yet, compute once the
* whole CASE expression is built.
*/
adjust_jumps = lappend_int(adjust_jumps,
state->steps_len - 1);
/*
* But we can set WHEN test's jump target now, to make it
* jump to the next WHEN subexpression or the ELSE.
*/
state->steps[whenstep].d.jump.jumpdone = state->steps_len;
}
/* transformCaseExpr always adds a default */
Assert(caseExpr->defresult);
/* evaluate ELSE expr into CASE's result variables */
ExecInitExprRec(caseExpr->defresult, state,
resv, resnull);
/* adjust jump targets */
foreach(lc, adjust_jumps)
{
ExprEvalStep *as = &state->steps[lfirst_int(lc)];
Assert(as->opcode == EEOP_JUMP);
Assert(as->d.jump.jumpdone == -1);
as->d.jump.jumpdone = state->steps_len;
}
break;
}
case T_CaseTestExpr:
{
/*
* Read from location identified by innermost_caseval. Note
* that innermost_caseval could be NULL, if this node isn't
* actually within a CaseExpr, ArrayCoerceExpr, etc structure.
* That can happen because some parts of the system abuse
* CaseTestExpr to cause a read of a value externally supplied
* in econtext->caseValue_datum. We'll take care of that
* scenario at runtime.
*/
scratch.opcode = EEOP_CASE_TESTVAL;
scratch.d.casetest.value = state->innermost_caseval;
scratch.d.casetest.isnull = state->innermost_casenull;
ExprEvalPushStep(state, &scratch);
break;
}
case T_ArrayExpr:
{
ArrayExpr *arrayexpr = (ArrayExpr *) node;
int nelems = list_length(arrayexpr->elements);
ListCell *lc;
int elemoff;
/*
* Evaluate by computing each element, and then forming the
* array. Elements are computed into scratch arrays
* associated with the ARRAYEXPR step.
*/
scratch.opcode = EEOP_ARRAYEXPR;
scratch.d.arrayexpr.elemvalues =
(Datum *) palloc(sizeof(Datum) * nelems);
scratch.d.arrayexpr.elemnulls =
(bool *) palloc(sizeof(bool) * nelems);
scratch.d.arrayexpr.nelems = nelems;
/* fill remaining fields of step */
scratch.d.arrayexpr.multidims = arrayexpr->multidims;
scratch.d.arrayexpr.elemtype = arrayexpr->element_typeid;
/* do one-time catalog lookup for type info */
get_typlenbyvalalign(arrayexpr->element_typeid,
&scratch.d.arrayexpr.elemlength,
&scratch.d.arrayexpr.elembyval,
&scratch.d.arrayexpr.elemalign);
/* prepare to evaluate all arguments */
elemoff = 0;
foreach(lc, arrayexpr->elements)
{
Expr *e = (Expr *) lfirst(lc);
ExecInitExprRec(e, state,
&scratch.d.arrayexpr.elemvalues[elemoff],
&scratch.d.arrayexpr.elemnulls[elemoff]);
elemoff++;
}
/* and then collect all into an array */
ExprEvalPushStep(state, &scratch);
break;
}
case T_RowExpr:
{
RowExpr *rowexpr = (RowExpr *) node;
int nelems = list_length(rowexpr->args);
TupleDesc tupdesc;
int i;
ListCell *l;
/* Build tupdesc to describe result tuples */
if (rowexpr->row_typeid == RECORDOID)
{
/* generic record, use types of given expressions */
tupdesc = ExecTypeFromExprList(rowexpr->args);
}
else
{
/* it's been cast to a named type, use that */
tupdesc = lookup_rowtype_tupdesc_copy(rowexpr->row_typeid, -1);
}
/* In either case, adopt RowExpr's column aliases */
ExecTypeSetColNames(tupdesc, rowexpr->colnames);
/* Bless the tupdesc in case it's now of type RECORD */
BlessTupleDesc(tupdesc);
/*
* In the named-type case, the tupdesc could have more columns
* than are in the args list, since the type might have had
* columns added since the ROW() was parsed. We want those
* extra columns to go to nulls, so we make sure that the
* workspace arrays are large enough and then initialize any
* extra columns to read as NULLs.
*/
Assert(nelems <= tupdesc->natts);
nelems = Max(nelems, tupdesc->natts);
/*
* Evaluate by first building datums for each field, and then
* a final step forming the composite datum.
*/
scratch.opcode = EEOP_ROW;
scratch.d.row.tupdesc = tupdesc;
/* space for the individual field datums */
scratch.d.row.elemvalues =
(Datum *) palloc(sizeof(Datum) * nelems);
scratch.d.row.elemnulls =
(bool *) palloc(sizeof(bool) * nelems);
/* as explained above, make sure any extra columns are null */
memset(scratch.d.row.elemnulls, true, sizeof(bool) * nelems);
/* Set up evaluation, skipping any deleted columns */
i = 0;
foreach(l, rowexpr->args)
{
Form_pg_attribute att = TupleDescAttr(tupdesc, i);
Expr *e = (Expr *) lfirst(l);
if (!att->attisdropped)
{
/*
* Guard against ALTER COLUMN TYPE on rowtype since
* the RowExpr was created. XXX should we check
* typmod too? Not sure we can be sure it'll be the
* same.
*/
if (exprType((Node *) e) != att->atttypid)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("ROW() column has type %s instead of type %s",
format_type_be(exprType((Node *) e)),
format_type_be(att->atttypid))));
}
else
{
/*
* Ignore original expression and insert a NULL. We
* don't really care what type of NULL it is, so
* always make an int4 NULL.
*/
e = (Expr *) makeNullConst(INT4OID, -1, InvalidOid);
}
/* Evaluate column expr into appropriate workspace slot */
ExecInitExprRec(e, state,
&scratch.d.row.elemvalues[i],
&scratch.d.row.elemnulls[i]);
i++;
}
/* And finally build the row value */
ExprEvalPushStep(state, &scratch);
break;
}
case T_RowCompareExpr:
{
RowCompareExpr *rcexpr = (RowCompareExpr *) node;
int nopers = list_length(rcexpr->opnos);
List *adjust_jumps = NIL;
ListCell *l_left_expr,
*l_right_expr,
*l_opno,
*l_opfamily,
*l_inputcollid;
ListCell *lc;
/*
* Iterate over each field, prepare comparisons. To handle
* NULL results, prepare jumps to after the expression. If a
* comparison yields a != 0 result, jump to the final step.
*/
Assert(list_length(rcexpr->largs) == nopers);
Assert(list_length(rcexpr->rargs) == nopers);
Assert(list_length(rcexpr->opfamilies) == nopers);
Assert(list_length(rcexpr->inputcollids) == nopers);
forfive(l_left_expr, rcexpr->largs,
l_right_expr, rcexpr->rargs,
l_opno, rcexpr->opnos,
l_opfamily, rcexpr->opfamilies,
l_inputcollid, rcexpr->inputcollids)
{
Expr *left_expr = (Expr *) lfirst(l_left_expr);
Expr *right_expr = (Expr *) lfirst(l_right_expr);
Oid opno = lfirst_oid(l_opno);
Oid opfamily = lfirst_oid(l_opfamily);
Oid inputcollid = lfirst_oid(l_inputcollid);
int strategy;
Oid lefttype;
Oid righttype;
Oid proc;
FmgrInfo *finfo;
FunctionCallInfo fcinfo;
get_op_opfamily_properties(opno, opfamily, false,
&strategy,
&lefttype,
&righttype);
proc = get_opfamily_proc(opfamily,
lefttype,
righttype,
BTORDER_PROC);
if (!OidIsValid(proc))
elog(ERROR, "missing support function %d(%u,%u) in opfamily %u",
BTORDER_PROC, lefttype, righttype, opfamily);
/* Set up the primary fmgr lookup information */
finfo = palloc0(sizeof(FmgrInfo));
fcinfo = palloc0(SizeForFunctionCallInfo(2));
fmgr_info(proc, finfo);
fmgr_info_set_expr((Node *) node, finfo);
InitFunctionCallInfoData(*fcinfo, finfo, 2,
inputcollid, NULL, NULL);
/*
* If we enforced permissions checks on index support
* functions, we'd need to make a check here. But the
* index support machinery doesn't do that, and thus
* neither does this code.
*/
/* evaluate left and right args directly into fcinfo */
ExecInitExprRec(left_expr, state,
&fcinfo->args[0].value, &fcinfo->args[0].isnull);
ExecInitExprRec(right_expr, state,
&fcinfo->args[1].value, &fcinfo->args[1].isnull);
scratch.opcode = EEOP_ROWCOMPARE_STEP;
scratch.d.rowcompare_step.finfo = finfo;
scratch.d.rowcompare_step.fcinfo_data = fcinfo;
scratch.d.rowcompare_step.fn_addr = finfo->fn_addr;
/* jump targets filled below */
scratch.d.rowcompare_step.jumpnull = -1;
scratch.d.rowcompare_step.jumpdone = -1;
ExprEvalPushStep(state, &scratch);
adjust_jumps = lappend_int(adjust_jumps,
state->steps_len - 1);
}
/*
* We could have a zero-column rowtype, in which case the rows
* necessarily compare equal.
*/
if (nopers == 0)
{
scratch.opcode = EEOP_CONST;
scratch.d.constval.value = Int32GetDatum(0);
scratch.d.constval.isnull = false;
ExprEvalPushStep(state, &scratch);
}
/* Finally, examine the last comparison result */
scratch.opcode = EEOP_ROWCOMPARE_FINAL;
scratch.d.rowcompare_final.rctype = rcexpr->rctype;
ExprEvalPushStep(state, &scratch);
/* adjust jump targets */
foreach(lc, adjust_jumps)
{
ExprEvalStep *as = &state->steps[lfirst_int(lc)];
Assert(as->opcode == EEOP_ROWCOMPARE_STEP);
Assert(as->d.rowcompare_step.jumpdone == -1);
Assert(as->d.rowcompare_step.jumpnull == -1);
/* jump to comparison evaluation */
as->d.rowcompare_step.jumpdone = state->steps_len - 1;
/* jump to the following expression */
as->d.rowcompare_step.jumpnull = state->steps_len;
}
break;
}
case T_CoalesceExpr:
{
CoalesceExpr *coalesce = (CoalesceExpr *) node;
List *adjust_jumps = NIL;
ListCell *lc;
/* We assume there's at least one arg */
Assert(coalesce->args != NIL);
/*
* Prepare evaluation of all coalesced arguments, after each
* one push a step that short-circuits if not null.
*/
foreach(lc, coalesce->args)
{
Expr *e = (Expr *) lfirst(lc);
/* evaluate argument, directly into result datum */
ExecInitExprRec(e, state, resv, resnull);
/* if it's not null, skip to end of COALESCE expr */
scratch.opcode = EEOP_JUMP_IF_NOT_NULL;
scratch.d.jump.jumpdone = -1; /* adjust later */
ExprEvalPushStep(state, &scratch);
adjust_jumps = lappend_int(adjust_jumps,
state->steps_len - 1);
}
/*
* No need to add a constant NULL return - we only can get to
* the end of the expression if a NULL already is being
* returned.
*/
/* adjust jump targets */
foreach(lc, adjust_jumps)
{
ExprEvalStep *as = &state->steps[lfirst_int(lc)];
Assert(as->opcode == EEOP_JUMP_IF_NOT_NULL);
Assert(as->d.jump.jumpdone == -1);
as->d.jump.jumpdone = state->steps_len;
}
break;
}
case T_MinMaxExpr:
{
MinMaxExpr *minmaxexpr = (MinMaxExpr *) node;
int nelems = list_length(minmaxexpr->args);
TypeCacheEntry *typentry;
FmgrInfo *finfo;
FunctionCallInfo fcinfo;
ListCell *lc;
int off;
/* Look up the btree comparison function for the datatype */
typentry = lookup_type_cache(minmaxexpr->minmaxtype,
TYPECACHE_CMP_PROC);
if (!OidIsValid(typentry->cmp_proc))
ereport(ERROR,
(errcode(ERRCODE_UNDEFINED_FUNCTION),
errmsg("could not identify a comparison function for type %s",
format_type_be(minmaxexpr->minmaxtype))));
/*
* If we enforced permissions checks on index support
* functions, we'd need to make a check here. But the index
* support machinery doesn't do that, and thus neither does
* this code.
*/
/* Perform function lookup */
finfo = palloc0(sizeof(FmgrInfo));
fcinfo = palloc0(SizeForFunctionCallInfo(2));
fmgr_info(typentry->cmp_proc, finfo);
fmgr_info_set_expr((Node *) node, finfo);
InitFunctionCallInfoData(*fcinfo, finfo, 2,
minmaxexpr->inputcollid, NULL, NULL);
scratch.opcode = EEOP_MINMAX;
/* allocate space to store arguments */
scratch.d.minmax.values =
(Datum *) palloc(sizeof(Datum) * nelems);
scratch.d.minmax.nulls =
(bool *) palloc(sizeof(bool) * nelems);
scratch.d.minmax.nelems = nelems;
scratch.d.minmax.op = minmaxexpr->op;
scratch.d.minmax.finfo = finfo;
scratch.d.minmax.fcinfo_data = fcinfo;
/* evaluate expressions into minmax->values/nulls */
off = 0;
foreach(lc, minmaxexpr->args)
{
Expr *e = (Expr *) lfirst(lc);
ExecInitExprRec(e, state,
&scratch.d.minmax.values[off],
&scratch.d.minmax.nulls[off]);
off++;
}
/* and push the final comparison */
ExprEvalPushStep(state, &scratch);
break;
}
case T_SQLValueFunction:
{
SQLValueFunction *svf = (SQLValueFunction *) node;
scratch.opcode = EEOP_SQLVALUEFUNCTION;
scratch.d.sqlvaluefunction.svf = svf;
ExprEvalPushStep(state, &scratch);
break;
}
case T_XmlExpr:
{
XmlExpr *xexpr = (XmlExpr *) node;
int nnamed = list_length(xexpr->named_args);
int nargs = list_length(xexpr->args);
int off;
ListCell *arg;
scratch.opcode = EEOP_XMLEXPR;
scratch.d.xmlexpr.xexpr = xexpr;
/* allocate space for storing all the arguments */
if (nnamed)
{
scratch.d.xmlexpr.named_argvalue =
(Datum *) palloc(sizeof(Datum) * nnamed);
scratch.d.xmlexpr.named_argnull =
(bool *) palloc(sizeof(bool) * nnamed);
}
else
{
scratch.d.xmlexpr.named_argvalue = NULL;
scratch.d.xmlexpr.named_argnull = NULL;
}
if (nargs)
{
scratch.d.xmlexpr.argvalue =
(Datum *) palloc(sizeof(Datum) * nargs);
scratch.d.xmlexpr.argnull =
(bool *) palloc(sizeof(bool) * nargs);
}
else
{
scratch.d.xmlexpr.argvalue = NULL;
scratch.d.xmlexpr.argnull = NULL;
}
/* prepare argument execution */
off = 0;
foreach(arg, xexpr->named_args)
{
Expr *e = (Expr *) lfirst(arg);
ExecInitExprRec(e, state,
&scratch.d.xmlexpr.named_argvalue[off],
&scratch.d.xmlexpr.named_argnull[off]);
off++;
}
off = 0;
foreach(arg, xexpr->args)
{
Expr *e = (Expr *) lfirst(arg);
ExecInitExprRec(e, state,
&scratch.d.xmlexpr.argvalue[off],
&scratch.d.xmlexpr.argnull[off]);
off++;
}
/* and evaluate the actual XML expression */
ExprEvalPushStep(state, &scratch);
break;
}
case T_NullTest:
{
NullTest *ntest = (NullTest *) node;
if (ntest->nulltesttype == IS_NULL)
{
if (ntest->argisrow)
scratch.opcode = EEOP_NULLTEST_ROWISNULL;
else
scratch.opcode = EEOP_NULLTEST_ISNULL;
}
else if (ntest->nulltesttype == IS_NOT_NULL)
{
if (ntest->argisrow)
scratch.opcode = EEOP_NULLTEST_ROWISNOTNULL;
else
scratch.opcode = EEOP_NULLTEST_ISNOTNULL;
}
else
{
elog(ERROR, "unrecognized nulltesttype: %d",
(int) ntest->nulltesttype);
}
/* initialize cache in case it's a row test */
scratch.d.nulltest_row.rowcache.cacheptr = NULL;
/* first evaluate argument into result variable */
ExecInitExprRec(ntest->arg, state,
resv, resnull);
/* then push the test of that argument */
ExprEvalPushStep(state, &scratch);
break;
}
case T_BooleanTest:
{
BooleanTest *btest = (BooleanTest *) node;
/*
* Evaluate argument, directly into result datum. That's ok,
* because resv/resnull is definitely not used anywhere else,
* and will get overwritten by the below EEOP_BOOLTEST_IS_*
* step.
*/
ExecInitExprRec(btest->arg, state, resv, resnull);
switch (btest->booltesttype)
{
case IS_TRUE:
scratch.opcode = EEOP_BOOLTEST_IS_TRUE;
break;
case IS_NOT_TRUE:
scratch.opcode = EEOP_BOOLTEST_IS_NOT_TRUE;
break;
case IS_FALSE:
scratch.opcode = EEOP_BOOLTEST_IS_FALSE;
break;
case IS_NOT_FALSE:
scratch.opcode = EEOP_BOOLTEST_IS_NOT_FALSE;
break;
case IS_UNKNOWN:
/* Same as scalar IS NULL test */
scratch.opcode = EEOP_NULLTEST_ISNULL;
break;
case IS_NOT_UNKNOWN:
/* Same as scalar IS NOT NULL test */
scratch.opcode = EEOP_NULLTEST_ISNOTNULL;
break;
default:
elog(ERROR, "unrecognized booltesttype: %d",
(int) btest->booltesttype);
}
ExprEvalPushStep(state, &scratch);
break;
}
case T_CoerceToDomain:
{
CoerceToDomain *ctest = (CoerceToDomain *) node;
ExecInitCoerceToDomain(&scratch, ctest, state,
resv, resnull);
break;
}
case T_CoerceToDomainValue:
{
/*
* Read from location identified by innermost_domainval. Note
* that innermost_domainval could be NULL, if we're compiling
* a standalone domain check rather than one embedded in a
* larger expression. In that case we must read from
* econtext->domainValue_datum. We'll take care of that
* scenario at runtime.
*/
scratch.opcode = EEOP_DOMAIN_TESTVAL;
/* we share instruction union variant with case testval */
scratch.d.casetest.value = state->innermost_domainval;
scratch.d.casetest.isnull = state->innermost_domainnull;
ExprEvalPushStep(state, &scratch);
break;
}
case T_CurrentOfExpr:
{
scratch.opcode = EEOP_CURRENTOFEXPR;
ExprEvalPushStep(state, &scratch);
break;
}
case T_NextValueExpr:
{
NextValueExpr *nve = (NextValueExpr *) node;
scratch.opcode = EEOP_NEXTVALUEEXPR;
scratch.d.nextvalueexpr.seqid = nve->seqid;
scratch.d.nextvalueexpr.seqtypid = nve->typeId;
ExprEvalPushStep(state, &scratch);
break;
}
default:
elog(ERROR, "unrecognized node type: %d",
(int) nodeTag(node));
break;
}
}
/*
* Add another expression evaluation step to ExprState->steps.
*
* Note that this potentially re-allocates es->steps, therefore no pointer
* into that array may be used while the expression is still being built.
*/
void
ExprEvalPushStep(ExprState *es, const ExprEvalStep *s)
{
if (es->steps_alloc == 0)
{
es->steps_alloc = 16;
es->steps = palloc(sizeof(ExprEvalStep) * es->steps_alloc);
}
else if (es->steps_alloc == es->steps_len)
{
es->steps_alloc *= 2;
es->steps = repalloc(es->steps,
sizeof(ExprEvalStep) * es->steps_alloc);
}
memcpy(&es->steps[es->steps_len++], s, sizeof(ExprEvalStep));
}
/*
* Perform setup necessary for the evaluation of a function-like expression,
* appending argument evaluation steps to the steps list in *state, and
* setting up *scratch so it is ready to be pushed.
*
* *scratch is not pushed here, so that callers may override the opcode,
* which is useful for function-like cases like DISTINCT.
*/
static void
ExecInitFunc(ExprEvalStep *scratch, Expr *node, List *args, Oid funcid,
Oid inputcollid, ExprState *state)
{
int nargs = list_length(args);
AclResult aclresult;
FmgrInfo *flinfo;
FunctionCallInfo fcinfo;
int argno;
ListCell *lc;
/* Check permission to call function */
aclresult = pg_proc_aclcheck(funcid, GetUserId(), ACL_EXECUTE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, OBJECT_FUNCTION, get_func_name(funcid));
InvokeFunctionExecuteHook(funcid);
/*
* Safety check on nargs. Under normal circumstances this should never
* fail, as parser should check sooner. But possibly it might fail if
* server has been compiled with FUNC_MAX_ARGS smaller than some functions
* declared in pg_proc?
*/
if (nargs > FUNC_MAX_ARGS)
ereport(ERROR,
(errcode(ERRCODE_TOO_MANY_ARGUMENTS),
errmsg_plural("cannot pass more than %d argument to a function",
"cannot pass more than %d arguments to a function",
FUNC_MAX_ARGS,
FUNC_MAX_ARGS)));
/* Allocate function lookup data and parameter workspace for this call */
scratch->d.func.finfo = palloc0(sizeof(FmgrInfo));
scratch->d.func.fcinfo_data = palloc0(SizeForFunctionCallInfo(nargs));
flinfo = scratch->d.func.finfo;
fcinfo = scratch->d.func.fcinfo_data;
/* Set up the primary fmgr lookup information */
fmgr_info(funcid, flinfo);
fmgr_info_set_expr((Node *) node, flinfo);
/* Initialize function call parameter structure too */
InitFunctionCallInfoData(*fcinfo, flinfo,
nargs, inputcollid, NULL, NULL);
/* Keep extra copies of this info to save an indirection at runtime */
scratch->d.func.fn_addr = flinfo->fn_addr;
scratch->d.func.nargs = nargs;
/* We only support non-set functions here */
if (flinfo->fn_retset)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("set-valued function called in context that cannot accept a set"),
state->parent ?
executor_errposition(state->parent->state,
exprLocation((Node *) node)) : 0));
/* Build code to evaluate arguments directly into the fcinfo struct */
argno = 0;
foreach(lc, args)
{
Expr *arg = (Expr *) lfirst(lc);
if (IsA(arg, Const))
{
/*
* Don't evaluate const arguments every round; especially
* interesting for constants in comparisons.
*/
Const *con = (Const *) arg;
fcinfo->args[argno].value = con->constvalue;
fcinfo->args[argno].isnull = con->constisnull;
}
else
{
ExecInitExprRec(arg, state,
&fcinfo->args[argno].value,
&fcinfo->args[argno].isnull);
}
argno++;
}
/* Insert appropriate opcode depending on strictness and stats level */
if (pgstat_track_functions <= flinfo->fn_stats)
{
if (flinfo->fn_strict && nargs > 0)
scratch->opcode = EEOP_FUNCEXPR_STRICT;
else
scratch->opcode = EEOP_FUNCEXPR;
}
else
{
if (flinfo->fn_strict && nargs > 0)
scratch->opcode = EEOP_FUNCEXPR_STRICT_FUSAGE;
else
scratch->opcode = EEOP_FUNCEXPR_FUSAGE;
}
}
/*
* Add expression steps deforming the ExprState's inner/outer/scan slots
* as much as required by the expression.
*/
static void
ExecInitExprSlots(ExprState *state, Node *node)
{
LastAttnumInfo info = {0, 0, 0};
/*
* Figure out which attributes we're going to need.
*/
get_last_attnums_walker(node, &info);
ExecPushExprSlots(state, &info);
}
/*
* Add steps deforming the ExprState's inner/out/scan slots as much as
* indicated by info. This is useful when building an ExprState covering more
* than one expression.
*/
static void
ExecPushExprSlots(ExprState *state, LastAttnumInfo *info)
{
ExprEvalStep scratch = {0};
scratch.resvalue = NULL;
scratch.resnull = NULL;
/* Emit steps as needed */
if (info->last_inner > 0)
{
scratch.opcode = EEOP_INNER_FETCHSOME;
scratch.d.fetch.last_var = info->last_inner;
scratch.d.fetch.fixed = false;
scratch.d.fetch.kind = NULL;
scratch.d.fetch.known_desc = NULL;
if (ExecComputeSlotInfo(state, &scratch))
ExprEvalPushStep(state, &scratch);
}
if (info->last_outer > 0)
{
scratch.opcode = EEOP_OUTER_FETCHSOME;
scratch.d.fetch.last_var = info->last_outer;
scratch.d.fetch.fixed = false;
scratch.d.fetch.kind = NULL;
scratch.d.fetch.known_desc = NULL;
if (ExecComputeSlotInfo(state, &scratch))
ExprEvalPushStep(state, &scratch);
}
if (info->last_scan > 0)
{
scratch.opcode = EEOP_SCAN_FETCHSOME;
scratch.d.fetch.last_var = info->last_scan;
scratch.d.fetch.fixed = false;
scratch.d.fetch.kind = NULL;
scratch.d.fetch.known_desc = NULL;
if (ExecComputeSlotInfo(state, &scratch))
ExprEvalPushStep(state, &scratch);
}
}
/*
* get_last_attnums_walker: expression walker for ExecInitExprSlots
*/
static bool
get_last_attnums_walker(Node *node, LastAttnumInfo *info)
{
if (node == NULL)
return false;
if (IsA(node, Var))
{
Var *variable = (Var *) node;
AttrNumber attnum = variable->varattno;
switch (variable->varno)
{
case INNER_VAR:
info->last_inner = Max(info->last_inner, attnum);
break;
case OUTER_VAR:
info->last_outer = Max(info->last_outer, attnum);
break;
/* INDEX_VAR is handled by default case */
default:
info->last_scan = Max(info->last_scan, attnum);
break;
}
return false;
}
/*
* Don't examine the arguments or filters of Aggrefs or WindowFuncs,
* because those do not represent expressions to be evaluated within the
* calling expression's econtext. GroupingFunc arguments are never
* evaluated at all.
*/
if (IsA(node, Aggref))
return false;
if (IsA(node, WindowFunc))
return false;
if (IsA(node, GroupingFunc))
return false;
return expression_tree_walker(node, get_last_attnums_walker,
(void *) info);
}
/*
* Compute additional information for EEOP_*_FETCHSOME ops.
*
* The goal is to determine whether a slot is 'fixed', that is, every
* evaluation of the expression will have the same type of slot, with an
* equivalent descriptor.
*
* Returns true if the deforming step is required, false otherwise.
*/
static bool
ExecComputeSlotInfo(ExprState *state, ExprEvalStep *op)
{
PlanState *parent = state->parent;
TupleDesc desc = NULL;
const TupleTableSlotOps *tts_ops = NULL;
bool isfixed = false;
ExprEvalOp opcode = op->opcode;
Assert(opcode == EEOP_INNER_FETCHSOME ||
opcode == EEOP_OUTER_FETCHSOME ||
opcode == EEOP_SCAN_FETCHSOME);
if (op->d.fetch.known_desc != NULL)
{
desc = op->d.fetch.known_desc;
tts_ops = op->d.fetch.kind;
isfixed = op->d.fetch.kind != NULL;
}
else if (!parent)
{
isfixed = false;
}
else if (opcode == EEOP_INNER_FETCHSOME)
{
PlanState *is = innerPlanState(parent);
if (parent->inneropsset && !parent->inneropsfixed)
{
isfixed = false;
}
else if (parent->inneropsset && parent->innerops)
{
isfixed = true;
tts_ops = parent->innerops;
desc = ExecGetResultType(is);
}
else if (is)
{
tts_ops = ExecGetResultSlotOps(is, &isfixed);
desc = ExecGetResultType(is);
}
}
else if (opcode == EEOP_OUTER_FETCHSOME)
{
PlanState *os = outerPlanState(parent);
if (parent->outeropsset && !parent->outeropsfixed)
{
isfixed = false;
}
else if (parent->outeropsset && parent->outerops)
{
isfixed = true;
tts_ops = parent->outerops;
desc = ExecGetResultType(os);
}
else if (os)
{
tts_ops = ExecGetResultSlotOps(os, &isfixed);
desc = ExecGetResultType(os);
}
}
else if (opcode == EEOP_SCAN_FETCHSOME)
{
desc = parent->scandesc;
if (parent->scanops)
tts_ops = parent->scanops;
if (parent->scanopsset)
isfixed = parent->scanopsfixed;
}
if (isfixed && desc != NULL && tts_ops != NULL)
{
op->d.fetch.fixed = true;
op->d.fetch.kind = tts_ops;
op->d.fetch.known_desc = desc;
}
else
{
op->d.fetch.fixed = false;
op->d.fetch.kind = NULL;
op->d.fetch.known_desc = NULL;
}
/* if the slot is known to always virtual we never need to deform */
if (op->d.fetch.fixed && op->d.fetch.kind == &TTSOpsVirtual)
return false;
return true;
}
/*
* Prepare step for the evaluation of a whole-row variable.
* The caller still has to push the step.
*/
static void
ExecInitWholeRowVar(ExprEvalStep *scratch, Var *variable, ExprState *state)
{
PlanState *parent = state->parent;
/* fill in all but the target */
scratch->opcode = EEOP_WHOLEROW;
scratch->d.wholerow.var = variable;
scratch->d.wholerow.first = true;
scratch->d.wholerow.slow = false;
scratch->d.wholerow.tupdesc = NULL; /* filled at runtime */
scratch->d.wholerow.junkFilter = NULL;
/*
* If the input tuple came from a subquery, it might contain "resjunk"
* columns (such as GROUP BY or ORDER BY columns), which we don't want to
* keep in the whole-row result. We can get rid of such columns by
* passing the tuple through a JunkFilter --- but to make one, we have to
* lay our hands on the subquery's targetlist. Fortunately, there are not
* very many cases where this can happen, and we can identify all of them
* by examining our parent PlanState. We assume this is not an issue in
* standalone expressions that don't have parent plans. (Whole-row Vars
* can occur in such expressions, but they will always be referencing
* table rows.)
*/
if (parent)
{
PlanState *subplan = NULL;
switch (nodeTag(parent))
{
case T_SubqueryScanState:
subplan = ((SubqueryScanState *) parent)->subplan;
break;
case T_CteScanState:
subplan = ((CteScanState *) parent)->cteplanstate;
break;
default:
break;
}
if (subplan)
{
bool junk_filter_needed = false;
ListCell *tlist;
/* Detect whether subplan tlist actually has any junk columns */
foreach(tlist, subplan->plan->targetlist)
{
TargetEntry *tle = (TargetEntry *) lfirst(tlist);
if (tle->resjunk)
{
junk_filter_needed = true;
break;
}
}
/* If so, build the junkfilter now */
if (junk_filter_needed)
{
scratch->d.wholerow.junkFilter =
ExecInitJunkFilter(subplan->plan->targetlist,
ExecInitExtraTupleSlot(parent->state, NULL,
&TTSOpsVirtual));
}
}
}
}
/*
* Prepare evaluation of a SubscriptingRef expression.
*/
static void
ExecInitSubscriptingRef(ExprEvalStep *scratch, SubscriptingRef *sbsref,
ExprState *state, Datum *resv, bool *resnull)
{
bool isAssignment = (sbsref->refassgnexpr != NULL);
int nupper = list_length(sbsref->refupperindexpr);
int nlower = list_length(sbsref->reflowerindexpr);
const SubscriptRoutines *sbsroutines;
SubscriptingRefState *sbsrefstate;
SubscriptExecSteps methods;
char *ptr;
List *adjust_jumps = NIL;
ListCell *lc;
int i;
/* Look up the subscripting support methods */
sbsroutines = getSubscriptingRoutines(sbsref->refcontainertype, NULL);
if (!sbsroutines)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("cannot subscript type %s because it does not support subscripting",
format_type_be(sbsref->refcontainertype)),
state->parent ?
executor_errposition(state->parent->state,
exprLocation((Node *) sbsref)) : 0));
/* Allocate sbsrefstate, with enough space for per-subscript arrays too */
sbsrefstate = palloc0(MAXALIGN(sizeof(SubscriptingRefState)) +
(nupper + nlower) * (sizeof(Datum) +
2 * sizeof(bool)));
/* Fill constant fields of SubscriptingRefState */
sbsrefstate->isassignment = isAssignment;
sbsrefstate->numupper = nupper;
sbsrefstate->numlower = nlower;
/* Set up per-subscript arrays */
ptr = ((char *) sbsrefstate) + MAXALIGN(sizeof(SubscriptingRefState));
sbsrefstate->upperindex = (Datum *) ptr;
ptr += nupper * sizeof(Datum);
sbsrefstate->lowerindex = (Datum *) ptr;
ptr += nlower * sizeof(Datum);
sbsrefstate->upperprovided = (bool *) ptr;
ptr += nupper * sizeof(bool);
sbsrefstate->lowerprovided = (bool *) ptr;
ptr += nlower * sizeof(bool);
sbsrefstate->upperindexnull = (bool *) ptr;
ptr += nupper * sizeof(bool);
sbsrefstate->lowerindexnull = (bool *) ptr;
/* ptr += nlower * sizeof(bool); */
/*
* Let the container-type-specific code have a chance. It must fill the
* "methods" struct with function pointers for us to possibly use in
* execution steps below; and it can optionally set up some data pointed
* to by the workspace field.
*/
memset(&methods, 0, sizeof(methods));
sbsroutines->exec_setup(sbsref, sbsrefstate, &methods);
/*
* Evaluate array input. It's safe to do so into resv/resnull, because we
* won't use that as target for any of the other subexpressions, and it'll
* be overwritten by the final EEOP_SBSREF_FETCH/ASSIGN step, which is
* pushed last.
*/
ExecInitExprRec(sbsref->refexpr, state, resv, resnull);
/*
* If refexpr yields NULL, and the operation should be strict, then result
* is NULL. We can implement this with just JUMP_IF_NULL, since we
* evaluated the array into the desired target location.
*/
if (!isAssignment && sbsroutines->fetch_strict)
{
scratch->opcode = EEOP_JUMP_IF_NULL;
scratch->d.jump.jumpdone = -1; /* adjust later */
ExprEvalPushStep(state, scratch);
adjust_jumps = lappend_int(adjust_jumps,
state->steps_len - 1);
}
/* Evaluate upper subscripts */
i = 0;
foreach(lc, sbsref->refupperindexpr)
{
Expr *e = (Expr *) lfirst(lc);
/* When slicing, individual subscript bounds can be omitted */
if (!e)
{
sbsrefstate->upperprovided[i] = false;
sbsrefstate->upperindexnull[i] = true;
}
else
{
sbsrefstate->upperprovided[i] = true;
/* Each subscript is evaluated into appropriate array entry */
ExecInitExprRec(e, state,
&sbsrefstate->upperindex[i],
&sbsrefstate->upperindexnull[i]);
}
i++;
}
/* Evaluate lower subscripts similarly */
i = 0;
foreach(lc, sbsref->reflowerindexpr)
{
Expr *e = (Expr *) lfirst(lc);
/* When slicing, individual subscript bounds can be omitted */
if (!e)
{
sbsrefstate->lowerprovided[i] = false;
sbsrefstate->lowerindexnull[i] = true;
}
else
{
sbsrefstate->lowerprovided[i] = true;
/* Each subscript is evaluated into appropriate array entry */
ExecInitExprRec(e, state,
&sbsrefstate->lowerindex[i],
&sbsrefstate->lowerindexnull[i]);
}
i++;
}
/* SBSREF_SUBSCRIPTS checks and converts all the subscripts at once */
if (methods.sbs_check_subscripts)
{
scratch->opcode = EEOP_SBSREF_SUBSCRIPTS;
scratch->d.sbsref_subscript.subscriptfunc = methods.sbs_check_subscripts;
scratch->d.sbsref_subscript.state = sbsrefstate;
scratch->d.sbsref_subscript.jumpdone = -1; /* adjust later */
ExprEvalPushStep(state, scratch);
adjust_jumps = lappend_int(adjust_jumps,
state->steps_len - 1);
}
if (isAssignment)
{
Datum *save_innermost_caseval;
bool *save_innermost_casenull;
/* Check for unimplemented methods */
if (!methods.sbs_assign)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("type %s does not support subscripted assignment",
format_type_be(sbsref->refcontainertype))));
/*
* We might have a nested-assignment situation, in which the
* refassgnexpr is itself a FieldStore or SubscriptingRef that needs
* to obtain and modify the previous value of the array element or
* slice being replaced. If so, we have to extract that value from
* the array and pass it down via the CaseTestExpr mechanism. It's
* safe to reuse the CASE mechanism because there cannot be a CASE
* between here and where the value would be needed, and an array
* assignment can't be within a CASE either. (So saving and restoring
* innermost_caseval is just paranoia, but let's do it anyway.)
*
* Since fetching the old element might be a nontrivial expense, do it
* only if the argument actually needs it.
*/
if (isAssignmentIndirectionExpr(sbsref->refassgnexpr))
{
if (!methods.sbs_fetch_old)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("type %s does not support subscripted assignment",
format_type_be(sbsref->refcontainertype))));
scratch->opcode = EEOP_SBSREF_OLD;
scratch->d.sbsref.subscriptfunc = methods.sbs_fetch_old;
scratch->d.sbsref.state = sbsrefstate;
ExprEvalPushStep(state, scratch);
}
/* SBSREF_OLD puts extracted value into prevvalue/prevnull */
save_innermost_caseval = state->innermost_caseval;
save_innermost_casenull = state->innermost_casenull;
state->innermost_caseval = &sbsrefstate->prevvalue;
state->innermost_casenull = &sbsrefstate->prevnull;
/* evaluate replacement value into replacevalue/replacenull */
ExecInitExprRec(sbsref->refassgnexpr, state,
&sbsrefstate->replacevalue, &sbsrefstate->replacenull);
state->innermost_caseval = save_innermost_caseval;
state->innermost_casenull = save_innermost_casenull;
/* and perform the assignment */
scratch->opcode = EEOP_SBSREF_ASSIGN;
scratch->d.sbsref.subscriptfunc = methods.sbs_assign;
scratch->d.sbsref.state = sbsrefstate;
ExprEvalPushStep(state, scratch);
}
else
{
/* array fetch is much simpler */
scratch->opcode = EEOP_SBSREF_FETCH;
scratch->d.sbsref.subscriptfunc = methods.sbs_fetch;
scratch->d.sbsref.state = sbsrefstate;
ExprEvalPushStep(state, scratch);
}
/* adjust jump targets */
foreach(lc, adjust_jumps)
{
ExprEvalStep *as = &state->steps[lfirst_int(lc)];
if (as->opcode == EEOP_SBSREF_SUBSCRIPTS)
{
Assert(as->d.sbsref_subscript.jumpdone == -1);
as->d.sbsref_subscript.jumpdone = state->steps_len;
}
else
{
Assert(as->opcode == EEOP_JUMP_IF_NULL);
Assert(as->d.jump.jumpdone == -1);
as->d.jump.jumpdone = state->steps_len;
}
}
}
/*
* Helper for preparing SubscriptingRef expressions for evaluation: is expr
* a nested FieldStore or SubscriptingRef that needs the old element value
* passed down?
*
* (We could use this in FieldStore too, but in that case passing the old
* value is so cheap there's no need.)
*
* Note: it might seem that this needs to recurse, but in most cases it does
* not; the CaseTestExpr, if any, will be directly the arg or refexpr of the
* top-level node. Nested-assignment situations give rise to expression
* trees in which each level of assignment has its own CaseTestExpr, and the
* recursive structure appears within the newvals or refassgnexpr field.
* There is an exception, though: if the array is an array-of-domain, we will
* have a CoerceToDomain as the refassgnexpr, and we need to be able to look
* through that.
*/
static bool
isAssignmentIndirectionExpr(Expr *expr)
{
if (expr == NULL)
return false; /* just paranoia */
if (IsA(expr, FieldStore))
{
FieldStore *fstore = (FieldStore *) expr;
if (fstore->arg && IsA(fstore->arg, CaseTestExpr))
return true;
}
else if (IsA(expr, SubscriptingRef))
{
SubscriptingRef *sbsRef = (SubscriptingRef *) expr;
if (sbsRef->refexpr && IsA(sbsRef->refexpr, CaseTestExpr))
return true;
}
else if (IsA(expr, CoerceToDomain))
{
CoerceToDomain *cd = (CoerceToDomain *) expr;
return isAssignmentIndirectionExpr(cd->arg);
}
return false;
}
/*
* Prepare evaluation of a CoerceToDomain expression.
*/
static void
ExecInitCoerceToDomain(ExprEvalStep *scratch, CoerceToDomain *ctest,
ExprState *state, Datum *resv, bool *resnull)
{
DomainConstraintRef *constraint_ref;
Datum *domainval = NULL;
bool *domainnull = NULL;
ListCell *l;
scratch->d.domaincheck.resulttype = ctest->resulttype;
/* we'll allocate workspace only if needed */
scratch->d.domaincheck.checkvalue = NULL;
scratch->d.domaincheck.checknull = NULL;
/*
* Evaluate argument - it's fine to directly store it into resv/resnull,
* if there's constraint failures there'll be errors, otherwise it's what
* needs to be returned.
*/
ExecInitExprRec(ctest->arg, state, resv, resnull);
/*
* Note: if the argument is of varlena type, it could be a R/W expanded
* object. We want to return the R/W pointer as the final result, but we
* have to pass a R/O pointer as the value to be tested by any functions
* in check expressions. We don't bother to emit a MAKE_READONLY step
* unless there's actually at least one check expression, though. Until
* we've tested that, domainval/domainnull are NULL.
*/
/*
* Collect the constraints associated with the domain.
*
* Note: before PG v10 we'd recheck the set of constraints during each
* evaluation of the expression. Now we bake them into the ExprState
* during executor initialization. That means we don't need typcache.c to
* provide compiled exprs.
*/
constraint_ref = (DomainConstraintRef *)
palloc(sizeof(DomainConstraintRef));
InitDomainConstraintRef(ctest->resulttype,
constraint_ref,
CurrentMemoryContext,
false);
/*
* Compile code to check each domain constraint. NOTNULL constraints can
* just be applied on the resv/resnull value, but for CHECK constraints we
* need more pushups.
*/
foreach(l, constraint_ref->constraints)
{
DomainConstraintState *con = (DomainConstraintState *) lfirst(l);
Datum *save_innermost_domainval;
bool *save_innermost_domainnull;
scratch->d.domaincheck.constraintname = con->name;
switch (con->constrainttype)
{
case DOM_CONSTRAINT_NOTNULL:
scratch->opcode = EEOP_DOMAIN_NOTNULL;
ExprEvalPushStep(state, scratch);
break;
case DOM_CONSTRAINT_CHECK:
/* Allocate workspace for CHECK output if we didn't yet */
if (scratch->d.domaincheck.checkvalue == NULL)
{
scratch->d.domaincheck.checkvalue =
(Datum *) palloc(sizeof(Datum));
scratch->d.domaincheck.checknull =
(bool *) palloc(sizeof(bool));
}
/*
* If first time through, determine where CoerceToDomainValue
* nodes should read from.
*/
if (domainval == NULL)
{
/*
* Since value might be read multiple times, force to R/O
* - but only if it could be an expanded datum.
*/
if (get_typlen(ctest->resulttype) == -1)
{
ExprEvalStep scratch2 = {0};
/* Yes, so make output workspace for MAKE_READONLY */
domainval = (Datum *) palloc(sizeof(Datum));
domainnull = (bool *) palloc(sizeof(bool));
/* Emit MAKE_READONLY */
scratch2.opcode = EEOP_MAKE_READONLY;
scratch2.resvalue = domainval;
scratch2.resnull = domainnull;
scratch2.d.make_readonly.value = resv;
scratch2.d.make_readonly.isnull = resnull;
ExprEvalPushStep(state, &scratch2);
}
else
{
/* No, so it's fine to read from resv/resnull */
domainval = resv;
domainnull = resnull;
}
}
/*
* Set up value to be returned by CoerceToDomainValue nodes.
* We must save and restore innermost_domainval/null fields,
* in case this node is itself within a check expression for
* another domain.
*/
save_innermost_domainval = state->innermost_domainval;
save_innermost_domainnull = state->innermost_domainnull;
state->innermost_domainval = domainval;
state->innermost_domainnull = domainnull;
/* evaluate check expression value */
ExecInitExprRec(con->check_expr, state,
scratch->d.domaincheck.checkvalue,
scratch->d.domaincheck.checknull);
state->innermost_domainval = save_innermost_domainval;
state->innermost_domainnull = save_innermost_domainnull;
/* now test result */
scratch->opcode = EEOP_DOMAIN_CHECK;
ExprEvalPushStep(state, scratch);
break;
default:
elog(ERROR, "unrecognized constraint type: %d",
(int) con->constrainttype);
break;
}
}
}
/*
* Build transition/combine function invocations for all aggregate transition
* / combination function invocations in a grouping sets phase. This has to
* invoke all sort based transitions in a phase (if doSort is true), all hash
* based transitions (if doHash is true), or both (both true).
*
* The resulting expression will, for each set of transition values, first
* check for filters, evaluate aggregate input, check that that input is not
* NULL for a strict transition function, and then finally invoke the
* transition for each of the concurrently computed grouping sets.
*
* If nullcheck is true, the generated code will check for a NULL pointer to
* the array of AggStatePerGroup, and skip evaluation if so.
*/
ExprState *
ExecBuildAggTrans(AggState *aggstate, AggStatePerPhase phase,
bool doSort, bool doHash, bool nullcheck)
{
ExprState *state = makeNode(ExprState);
PlanState *parent = &aggstate->ss.ps;
ExprEvalStep scratch = {0};
bool isCombine = DO_AGGSPLIT_COMBINE(aggstate->aggsplit);
LastAttnumInfo deform = {0, 0, 0};
state->expr = (Expr *) aggstate;
state->parent = parent;
scratch.resvalue = &state->resvalue;
scratch.resnull = &state->resnull;
/*
* First figure out which slots, and how many columns from each, we're
* going to need.
*/
for (int transno = 0; transno < aggstate->numtrans; transno++)
{
AggStatePerTrans pertrans = &aggstate->pertrans[transno];
get_last_attnums_walker((Node *) pertrans->aggref->aggdirectargs,
&deform);
get_last_attnums_walker((Node *) pertrans->aggref->args,
&deform);
get_last_attnums_walker((Node *) pertrans->aggref->aggorder,
&deform);
get_last_attnums_walker((Node *) pertrans->aggref->aggdistinct,
&deform);
get_last_attnums_walker((Node *) pertrans->aggref->aggfilter,
&deform);
}
ExecPushExprSlots(state, &deform);
/*
* Emit instructions for each transition value / grouping set combination.
*/
for (int transno = 0; transno < aggstate->numtrans; transno++)
{
AggStatePerTrans pertrans = &aggstate->pertrans[transno];
FunctionCallInfo trans_fcinfo = pertrans->transfn_fcinfo;
List *adjust_bailout = NIL;
NullableDatum *strictargs = NULL;
bool *strictnulls = NULL;
int argno;
ListCell *bail;
/*
* If filter present, emit. Do so before evaluating the input, to
* avoid potentially unneeded computations, or even worse, unintended
* side-effects. When combining, all the necessary filtering has
* already been done.
*/
if (pertrans->aggref->aggfilter && !isCombine)
{
/* evaluate filter expression */
ExecInitExprRec(pertrans->aggref->aggfilter, state,
&state->resvalue, &state->resnull);
/* and jump out if false */
scratch.opcode = EEOP_JUMP_IF_NOT_TRUE;
scratch.d.jump.jumpdone = -1; /* adjust later */
ExprEvalPushStep(state, &scratch);
adjust_bailout = lappend_int(adjust_bailout,
state->steps_len - 1);
}
/*
* Evaluate arguments to aggregate/combine function.
*/
argno = 0;
if (isCombine)
{
/*
* Combining two aggregate transition values. Instead of directly
* coming from a tuple the input is a, potentially deserialized,
* transition value.
*/
TargetEntry *source_tle;
Assert(pertrans->numSortCols == 0);
Assert(list_length(pertrans->aggref->args) == 1);
strictargs = trans_fcinfo->args + 1;
source_tle = (TargetEntry *) linitial(pertrans->aggref->args);
/*
* deserialfn_oid will be set if we must deserialize the input
* state before calling the combine function.
*/
if (!OidIsValid(pertrans->deserialfn_oid))
{
/*
* Start from 1, since the 0th arg will be the transition
* value
*/
ExecInitExprRec(source_tle->expr, state,
&trans_fcinfo->args[argno + 1].value,
&trans_fcinfo->args[argno + 1].isnull);
}
else
{
FunctionCallInfo ds_fcinfo = pertrans->deserialfn_fcinfo;
/* evaluate argument */
ExecInitExprRec(source_tle->expr, state,
&ds_fcinfo->args[0].value,
&ds_fcinfo->args[0].isnull);
/* Dummy second argument for type-safety reasons */
ds_fcinfo->args[1].value = PointerGetDatum(NULL);
ds_fcinfo->args[1].isnull = false;
/*
* Don't call a strict deserialization function with NULL
* input
*/
if (pertrans->deserialfn.fn_strict)
scratch.opcode = EEOP_AGG_STRICT_DESERIALIZE;
else
scratch.opcode = EEOP_AGG_DESERIALIZE;
scratch.d.agg_deserialize.fcinfo_data = ds_fcinfo;
scratch.d.agg_deserialize.jumpnull = -1; /* adjust later */
scratch.resvalue = &trans_fcinfo->args[argno + 1].value;
scratch.resnull = &trans_fcinfo->args[argno + 1].isnull;
ExprEvalPushStep(state, &scratch);
/* don't add an adjustment unless the function is strict */
if (pertrans->deserialfn.fn_strict)
adjust_bailout = lappend_int(adjust_bailout,
state->steps_len - 1);
/* restore normal settings of scratch fields */
scratch.resvalue = &state->resvalue;
scratch.resnull = &state->resnull;
}
argno++;
}
else if (pertrans->numSortCols == 0)
{
ListCell *arg;
/*
* Normal transition function without ORDER BY / DISTINCT.
*/
strictargs = trans_fcinfo->args + 1;
foreach(arg, pertrans->aggref->args)
{
TargetEntry *source_tle = (TargetEntry *) lfirst(arg);
/*
* Start from 1, since the 0th arg will be the transition
* value
*/
ExecInitExprRec(source_tle->expr, state,
&trans_fcinfo->args[argno + 1].value,
&trans_fcinfo->args[argno + 1].isnull);
argno++;
}
}
else if (pertrans->numInputs == 1)
{
/*
* DISTINCT and/or ORDER BY case, with a single column sorted on.
*/
TargetEntry *source_tle =
(TargetEntry *) linitial(pertrans->aggref->args);
Assert(list_length(pertrans->aggref->args) == 1);
ExecInitExprRec(source_tle->expr, state,
&state->resvalue,
&state->resnull);
strictnulls = &state->resnull;
argno++;
}
else
{
/*
* DISTINCT and/or ORDER BY case, with multiple columns sorted on.
*/
Datum *values = pertrans->sortslot->tts_values;
bool *nulls = pertrans->sortslot->tts_isnull;
ListCell *arg;
strictnulls = nulls;
foreach(arg, pertrans->aggref->args)
{
TargetEntry *source_tle = (TargetEntry *) lfirst(arg);
ExecInitExprRec(source_tle->expr, state,
&values[argno], &nulls[argno]);
argno++;
}
}
Assert(pertrans->numInputs == argno);
/*
* For a strict transfn, nothing happens when there's a NULL input; we
* just keep the prior transValue. This is true for both plain and
* sorted/distinct aggregates.
*/
if (trans_fcinfo->flinfo->fn_strict && pertrans->numTransInputs > 0)
{
if (strictnulls)
scratch.opcode = EEOP_AGG_STRICT_INPUT_CHECK_NULLS;
else
scratch.opcode = EEOP_AGG_STRICT_INPUT_CHECK_ARGS;
scratch.d.agg_strict_input_check.nulls = strictnulls;
scratch.d.agg_strict_input_check.args = strictargs;
scratch.d.agg_strict_input_check.jumpnull = -1; /* adjust later */
scratch.d.agg_strict_input_check.nargs = pertrans->numTransInputs;
ExprEvalPushStep(state, &scratch);
adjust_bailout = lappend_int(adjust_bailout,
state->steps_len - 1);
}
/*
* Call transition function (once for each concurrently evaluated
* grouping set). Do so for both sort and hash based computations, as
* applicable.
*/
if (doSort)
{
int processGroupingSets = Max(phase->numsets, 1);
int setoff = 0;
for (int setno = 0; setno < processGroupingSets; setno++)
{
ExecBuildAggTransCall(state, aggstate, &scratch, trans_fcinfo,
pertrans, transno, setno, setoff, false,
nullcheck);
setoff++;
}
}
if (doHash)
{
int numHashes = aggstate->num_hashes;
int setoff;
/* in MIXED mode, there'll be preceding transition values */
if (aggstate->aggstrategy != AGG_HASHED)
setoff = aggstate->maxsets;
else
setoff = 0;
for (int setno = 0; setno < numHashes; setno++)
{
ExecBuildAggTransCall(state, aggstate, &scratch, trans_fcinfo,
pertrans, transno, setno, setoff, true,
nullcheck);
setoff++;
}
}
/* adjust early bail out jump target(s) */
foreach(bail, adjust_bailout)
{
ExprEvalStep *as = &state->steps[lfirst_int(bail)];
if (as->opcode == EEOP_JUMP_IF_NOT_TRUE)
{
Assert(as->d.jump.jumpdone == -1);
as->d.jump.jumpdone = state->steps_len;
}
else if (as->opcode == EEOP_AGG_STRICT_INPUT_CHECK_ARGS ||
as->opcode == EEOP_AGG_STRICT_INPUT_CHECK_NULLS)
{
Assert(as->d.agg_strict_input_check.jumpnull == -1);
as->d.agg_strict_input_check.jumpnull = state->steps_len;
}
else if (as->opcode == EEOP_AGG_STRICT_DESERIALIZE)
{
Assert(as->d.agg_deserialize.jumpnull == -1);
as->d.agg_deserialize.jumpnull = state->steps_len;
}
else
Assert(false);
}
}
scratch.resvalue = NULL;
scratch.resnull = NULL;
scratch.opcode = EEOP_DONE;
ExprEvalPushStep(state, &scratch);
ExecReadyExpr(state);
return state;
}
/*
* Build transition/combine function invocation for a single transition
* value. This is separated from ExecBuildAggTrans() because there are
* multiple callsites (hash and sort in some grouping set cases).
*/
static void
ExecBuildAggTransCall(ExprState *state, AggState *aggstate,
ExprEvalStep *scratch,
FunctionCallInfo fcinfo, AggStatePerTrans pertrans,
int transno, int setno, int setoff, bool ishash,
bool nullcheck)
{
ExprContext *aggcontext;
int adjust_jumpnull = -1;
if (ishash)
aggcontext = aggstate->hashcontext;
else
aggcontext = aggstate->aggcontexts[setno];
/* add check for NULL pointer? */
if (nullcheck)
{
scratch->opcode = EEOP_AGG_PLAIN_PERGROUP_NULLCHECK;
scratch->d.agg_plain_pergroup_nullcheck.setoff = setoff;
/* adjust later */
scratch->d.agg_plain_pergroup_nullcheck.jumpnull = -1;
ExprEvalPushStep(state, scratch);
adjust_jumpnull = state->steps_len - 1;
}
/*
* Determine appropriate transition implementation.
*
* For non-ordered aggregates:
*
* If the initial value for the transition state doesn't exist in the
* pg_aggregate table then we will let the first non-NULL value returned
* from the outer procNode become the initial value. (This is useful for
* aggregates like max() and min().) The noTransValue flag signals that we
* need to do so. If true, generate a
* EEOP_AGG_INIT_STRICT_PLAIN_TRANS{,_BYVAL} step. This step also needs to
* do the work described next:
*
* If the function is strict, but does have an initial value, choose
* EEOP_AGG_STRICT_PLAIN_TRANS{,_BYVAL}, which skips the transition
* function if the transition value has become NULL (because a previous
* transition function returned NULL). This step also needs to do the work
* described next:
*
* Otherwise we call EEOP_AGG_PLAIN_TRANS{,_BYVAL}, which does not have to
* perform either of the above checks.
*
* Having steps with overlapping responsibilities is not nice, but
* aggregations are very performance sensitive, making this worthwhile.
*
* For ordered aggregates:
*
* Only need to choose between the faster path for a single ordered
* column, and the one between multiple columns. Checking strictness etc
* is done when finalizing the aggregate. See
* process_ordered_aggregate_{single, multi} and
* advance_transition_function.
*/
if (pertrans->numSortCols == 0)
{
if (pertrans->transtypeByVal)
{
if (fcinfo->flinfo->fn_strict &&
pertrans->initValueIsNull)
scratch->opcode = EEOP_AGG_PLAIN_TRANS_INIT_STRICT_BYVAL;
else if (fcinfo->flinfo->fn_strict)
scratch->opcode = EEOP_AGG_PLAIN_TRANS_STRICT_BYVAL;
else
scratch->opcode = EEOP_AGG_PLAIN_TRANS_BYVAL;
}
else
{
if (fcinfo->flinfo->fn_strict &&
pertrans->initValueIsNull)
scratch->opcode = EEOP_AGG_PLAIN_TRANS_INIT_STRICT_BYREF;
else if (fcinfo->flinfo->fn_strict)
scratch->opcode = EEOP_AGG_PLAIN_TRANS_STRICT_BYREF;
else
scratch->opcode = EEOP_AGG_PLAIN_TRANS_BYREF;
}
}
else if (pertrans->numInputs == 1)
scratch->opcode = EEOP_AGG_ORDERED_TRANS_DATUM;
else
scratch->opcode = EEOP_AGG_ORDERED_TRANS_TUPLE;
scratch->d.agg_trans.pertrans = pertrans;
scratch->d.agg_trans.setno = setno;
scratch->d.agg_trans.setoff = setoff;
scratch->d.agg_trans.transno = transno;
scratch->d.agg_trans.aggcontext = aggcontext;
ExprEvalPushStep(state, scratch);
/* fix up jumpnull */
if (adjust_jumpnull != -1)
{
ExprEvalStep *as = &state->steps[adjust_jumpnull];
Assert(as->opcode == EEOP_AGG_PLAIN_PERGROUP_NULLCHECK);
Assert(as->d.agg_plain_pergroup_nullcheck.jumpnull == -1);
as->d.agg_plain_pergroup_nullcheck.jumpnull = state->steps_len;
}
}
/*
* Build equality expression that can be evaluated using ExecQual(), returning
* true if the expression context's inner/outer tuple are NOT DISTINCT. I.e
* two nulls match, a null and a not-null don't match.
*
* desc: tuple descriptor of the to-be-compared tuples
* numCols: the number of attributes to be examined
* keyColIdx: array of attribute column numbers
* eqFunctions: array of function oids of the equality functions to use
* parent: parent executor node
*/
ExprState *
ExecBuildGroupingEqual(TupleDesc ldesc, TupleDesc rdesc,
const TupleTableSlotOps *lops, const TupleTableSlotOps *rops,
int numCols,
const AttrNumber *keyColIdx,
const Oid *eqfunctions,
const Oid *collations,
PlanState *parent)
{
ExprState *state = makeNode(ExprState);
ExprEvalStep scratch = {0};
int maxatt = -1;
List *adjust_jumps = NIL;
ListCell *lc;
/*
* When no columns are actually compared, the result's always true. See
* special case in ExecQual().
*/
if (numCols == 0)
return NULL;
state->expr = NULL;
state->flags = EEO_FLAG_IS_QUAL;
state->parent = parent;
scratch.resvalue = &state->resvalue;
scratch.resnull = &state->resnull;
/* compute max needed attribute */
for (int natt = 0; natt < numCols; natt++)
{
int attno = keyColIdx[natt];
if (attno > maxatt)
maxatt = attno;
}
Assert(maxatt >= 0);
/* push deform steps */
scratch.opcode = EEOP_INNER_FETCHSOME;
scratch.d.fetch.last_var = maxatt;
scratch.d.fetch.fixed = false;
scratch.d.fetch.known_desc = ldesc;
scratch.d.fetch.kind = lops;
if (ExecComputeSlotInfo(state, &scratch))
ExprEvalPushStep(state, &scratch);
scratch.opcode = EEOP_OUTER_FETCHSOME;
scratch.d.fetch.last_var = maxatt;
scratch.d.fetch.fixed = false;
scratch.d.fetch.known_desc = rdesc;
scratch.d.fetch.kind = rops;
if (ExecComputeSlotInfo(state, &scratch))
ExprEvalPushStep(state, &scratch);
/*
* Start comparing at the last field (least significant sort key). That's
* the most likely to be different if we are dealing with sorted input.
*/
for (int natt = numCols; --natt >= 0;)
{
int attno = keyColIdx[natt];
Form_pg_attribute latt = TupleDescAttr(ldesc, attno - 1);
Form_pg_attribute ratt = TupleDescAttr(rdesc, attno - 1);
Oid foid = eqfunctions[natt];
Oid collid = collations[natt];
FmgrInfo *finfo;
FunctionCallInfo fcinfo;
AclResult aclresult;
/* Check permission to call function */
aclresult = pg_proc_aclcheck(foid, GetUserId(), ACL_EXECUTE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, OBJECT_FUNCTION, get_func_name(foid));
InvokeFunctionExecuteHook(foid);
/* Set up the primary fmgr lookup information */
finfo = palloc0(sizeof(FmgrInfo));
fcinfo = palloc0(SizeForFunctionCallInfo(2));
fmgr_info(foid, finfo);
fmgr_info_set_expr(NULL, finfo);
InitFunctionCallInfoData(*fcinfo, finfo, 2,
collid, NULL, NULL);
/* left arg */
scratch.opcode = EEOP_INNER_VAR;
scratch.d.var.attnum = attno - 1;
scratch.d.var.vartype = latt->atttypid;
scratch.resvalue = &fcinfo->args[0].value;
scratch.resnull = &fcinfo->args[0].isnull;
ExprEvalPushStep(state, &scratch);
/* right arg */
scratch.opcode = EEOP_OUTER_VAR;
scratch.d.var.attnum = attno - 1;
scratch.d.var.vartype = ratt->atttypid;
scratch.resvalue = &fcinfo->args[1].value;
scratch.resnull = &fcinfo->args[1].isnull;
ExprEvalPushStep(state, &scratch);
/* evaluate distinctness */
scratch.opcode = EEOP_NOT_DISTINCT;
scratch.d.func.finfo = finfo;
scratch.d.func.fcinfo_data = fcinfo;
scratch.d.func.fn_addr = finfo->fn_addr;
scratch.d.func.nargs = 2;
scratch.resvalue = &state->resvalue;
scratch.resnull = &state->resnull;
ExprEvalPushStep(state, &scratch);
/* then emit EEOP_QUAL to detect if result is false (or null) */
scratch.opcode = EEOP_QUAL;
scratch.d.qualexpr.jumpdone = -1;
scratch.resvalue = &state->resvalue;
scratch.resnull = &state->resnull;
ExprEvalPushStep(state, &scratch);
adjust_jumps = lappend_int(adjust_jumps,
state->steps_len - 1);
}
/* adjust jump targets */
foreach(lc, adjust_jumps)
{
ExprEvalStep *as = &state->steps[lfirst_int(lc)];
Assert(as->opcode == EEOP_QUAL);
Assert(as->d.qualexpr.jumpdone == -1);
as->d.qualexpr.jumpdone = state->steps_len;
}
scratch.resvalue = NULL;
scratch.resnull = NULL;
scratch.opcode = EEOP_DONE;
ExprEvalPushStep(state, &scratch);
ExecReadyExpr(state);
return state;
}
/*
* Build equality expression that can be evaluated using ExecQual(), returning
* true if the expression context's inner/outer tuples are equal. Datums in
* the inner/outer slots are assumed to be in the same order and quantity as
* the 'eqfunctions' parameter. NULLs are treated as equal.
*
* desc: tuple descriptor of the to-be-compared tuples
* lops: the slot ops for the inner tuple slots
* rops: the slot ops for the outer tuple slots
* eqFunctions: array of function oids of the equality functions to use
* this must be the same length as the 'param_exprs' list.
* collations: collation Oids to use for equality comparison. Must be the
* same length as the 'param_exprs' list.
* parent: parent executor node
*/
ExprState *
ExecBuildParamSetEqual(TupleDesc desc,
const TupleTableSlotOps *lops,
const TupleTableSlotOps *rops,
const Oid *eqfunctions,
const Oid *collations,
const List *param_exprs,
PlanState *parent)
{
ExprState *state = makeNode(ExprState);
ExprEvalStep scratch = {0};
int maxatt = list_length(param_exprs);
List *adjust_jumps = NIL;
ListCell *lc;
state->expr = NULL;
state->flags = EEO_FLAG_IS_QUAL;
state->parent = parent;
scratch.resvalue = &state->resvalue;
scratch.resnull = &state->resnull;
/* push deform steps */
scratch.opcode = EEOP_INNER_FETCHSOME;
scratch.d.fetch.last_var = maxatt;
scratch.d.fetch.fixed = false;
scratch.d.fetch.known_desc = desc;
scratch.d.fetch.kind = lops;
if (ExecComputeSlotInfo(state, &scratch))
ExprEvalPushStep(state, &scratch);
scratch.opcode = EEOP_OUTER_FETCHSOME;
scratch.d.fetch.last_var = maxatt;
scratch.d.fetch.fixed = false;
scratch.d.fetch.known_desc = desc;
scratch.d.fetch.kind = rops;
if (ExecComputeSlotInfo(state, &scratch))
ExprEvalPushStep(state, &scratch);
for (int attno = 0; attno < maxatt; attno++)
{
Form_pg_attribute att = TupleDescAttr(desc, attno);
Oid foid = eqfunctions[attno];
Oid collid = collations[attno];
FmgrInfo *finfo;
FunctionCallInfo fcinfo;
AclResult aclresult;
/* Check permission to call function */
aclresult = pg_proc_aclcheck(foid, GetUserId(), ACL_EXECUTE);
if (aclresult != ACLCHECK_OK)
aclcheck_error(aclresult, OBJECT_FUNCTION, get_func_name(foid));
InvokeFunctionExecuteHook(foid);
/* Set up the primary fmgr lookup information */
finfo = palloc0(sizeof(FmgrInfo));
fcinfo = palloc0(SizeForFunctionCallInfo(2));
fmgr_info(foid, finfo);
fmgr_info_set_expr(NULL, finfo);
InitFunctionCallInfoData(*fcinfo, finfo, 2,
collid, NULL, NULL);
/* left arg */
scratch.opcode = EEOP_INNER_VAR;
scratch.d.var.attnum = attno;
scratch.d.var.vartype = att->atttypid;
scratch.resvalue = &fcinfo->args[0].value;
scratch.resnull = &fcinfo->args[0].isnull;
ExprEvalPushStep(state, &scratch);
/* right arg */
scratch.opcode = EEOP_OUTER_VAR;
scratch.d.var.attnum = attno;
scratch.d.var.vartype = att->atttypid;
scratch.resvalue = &fcinfo->args[1].value;
scratch.resnull = &fcinfo->args[1].isnull;
ExprEvalPushStep(state, &scratch);
/* evaluate distinctness */
scratch.opcode = EEOP_NOT_DISTINCT;
scratch.d.func.finfo = finfo;
scratch.d.func.fcinfo_data = fcinfo;
scratch.d.func.fn_addr = finfo->fn_addr;
scratch.d.func.nargs = 2;
scratch.resvalue = &state->resvalue;
scratch.resnull = &state->resnull;
ExprEvalPushStep(state, &scratch);
/* then emit EEOP_QUAL to detect if result is false (or null) */
scratch.opcode = EEOP_QUAL;
scratch.d.qualexpr.jumpdone = -1;
scratch.resvalue = &state->resvalue;
scratch.resnull = &state->resnull;
ExprEvalPushStep(state, &scratch);
adjust_jumps = lappend_int(adjust_jumps,
state->steps_len - 1);
}
/* adjust jump targets */
foreach(lc, adjust_jumps)
{
ExprEvalStep *as = &state->steps[lfirst_int(lc)];
Assert(as->opcode == EEOP_QUAL);
Assert(as->d.qualexpr.jumpdone == -1);
as->d.qualexpr.jumpdone = state->steps_len;
}
scratch.resvalue = NULL;
scratch.resnull = NULL;
scratch.opcode = EEOP_DONE;
ExprEvalPushStep(state, &scratch);
ExecReadyExpr(state);
return state;
}
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