database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-13 07:41:39 +03:00
Code Activity

Replace the switching function ExecEvalExpr() with a macro that jumps

Browse Source 
directly to the appropriate per-node execution function, using a function
pointer stored by ExecInitExpr.  This speeds things up by eliminating one
level of function call.  The function-pointer technique also enables further
small improvements such as only making one-time tests once (and then
changing the function pointer).  Overall this seems to gain about 10%
on evaluation of simple expressions, which isn't earthshaking but seems
a worthwhile gain for a relatively small hack.  Per recent discussion
on pghackers.
This commit is contained in:
Tom Lane
2004-03-17 01:02:24 +00:00
parent 2c7e473434
commit c1352052ef
7 changed files with 419 additions and 309 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
src/backend/executor/nodeSubplan.c
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/executor/nodeSubplan.c,v 1.60 2004/01/14 23:01:54 tgl Exp $
* $PostgreSQL: pgsql/src/backend/executor/nodeSubplan.c,v 1.61 2004/03/17 01:02:23 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -47,10 +47,16 @@ static bool tupleAllNulls(HeapTuple tuple);
Datum
ExecSubPlan(SubPlanState *node,
ExprContext *econtext,
bool *isNull)
bool *isNull,
ExprDoneCond *isDone)
{
SubPlan *subplan = (SubPlan *) node->xprstate.expr;
/* Set default values for result flags: non-null, not a set result */
*isNull = false;
if (isDone)
*isDone = ExprSingleResult;
if (subplan->setParam != NIL)
elog(ERROR, "cannot set parent params from subquery");
@ -819,6 +825,7 @@ ExecInitSubPlan(SubPlanState *node, EState *estate)
expr);
tlestate = makeNode(GenericExprState);
tlestate->xprstate.expr = (Expr *) tle;
tlestate->xprstate.evalfunc = NULL;
tlestate->arg = exstate;
lefttlist = lappend(lefttlist, tlestate);
leftptlist = lappend(leftptlist, tle);
@ -834,6 +841,7 @@ ExecInitSubPlan(SubPlanState *node, EState *estate)
expr);
tlestate = makeNode(GenericExprState);
tlestate->xprstate.expr = (Expr *) tle;
tlestate->xprstate.evalfunc = NULL;
tlestate->arg = exstate;
righttlist = lappend(righttlist, tlestate);
rightptlist = lappend(rightptlist, tle);