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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2004-03-17 01:02:24 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2004-03-17 01:02:24 +0000 |
| commit | c1352052ef1d4eeb2eb1d822a207ddc2d106cb13 (patch) | |
| tree | cc396212df36959c1220a953a009636477c615b2 /src/backend/executor/nodeMergejoin.c | |
| parent | 2c7e47343449e2a4f7694d04a5a4284d89246699 (diff) | |
| download | postgresql-c1352052ef1d4eeb2eb1d822a207ddc2d106cb13.tar.gz postgresql-c1352052ef1d4eeb2eb1d822a207ddc2d106cb13.zip | |
Replace the switching function ExecEvalExpr() with a macro that jumps
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.
Diffstat (limited to 'src/backend/executor/nodeMergejoin.c')
| -rw-r--r-- | src/backend/executor/nodeMergejoin.c | 14 |
1 files changed, 5 insertions, 9 deletions
diff --git a/src/backend/executor/nodeMergejoin.c b/src/backend/executor/nodeMergejoin.c index 3bf929b4278..9c44102611a 100644 --- a/src/backend/executor/nodeMergejoin.c +++ b/src/backend/executor/nodeMergejoin.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/executor/nodeMergejoin.c,v 1.63 2003/11/29 19:51:48 pgsql Exp $ + * $PostgreSQL: pgsql/src/backend/executor/nodeMergejoin.c,v 1.64 2004/03/17 01:02:23 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -191,6 +191,8 @@ MergeCompare(List *eqQual, List *compareQual, ExprContext *econtext) eqclause = eqQual; foreach(clause, compareQual) { + ExprState *clauseexpr = (ExprState *) lfirst(clause); + ExprState *eqclauseexpr = (ExprState *) lfirst(eqclause); Datum const_value; bool isNull; @@ -200,10 +202,7 @@ MergeCompare(List *eqQual, List *compareQual, ExprContext *econtext) * * A NULL result is considered false. */ - const_value = ExecEvalExpr((ExprState *) lfirst(clause), - econtext, - &isNull, - NULL); + const_value = ExecEvalExpr(clauseexpr, econtext, &isNull, NULL); if (DatumGetBool(const_value) && !isNull) { @@ -217,10 +216,7 @@ MergeCompare(List *eqQual, List *compareQual, ExprContext *econtext) * key1 = key2 so we move on to the next pair of keys. *----------- */ - const_value = ExecEvalExpr((ExprState *) lfirst(eqclause), - econtext, - &isNull, - NULL); + const_value = ExecEvalExpr(eqclauseexpr, econtext, &isNull, NULL); if (!DatumGetBool(const_value) || isNull) break; /* return false */ |