Simplify ParamListInfo data structure to support only numbered parameters,

not named ones, and replace linear searches of the list with array indexing.
The named-parameter support has been dead code for many years anyway,
and recent profiling suggests that the searching was costing a noticeable
amount of performance for complex queries.

1 files changed, 14 insertions, 14 deletions

diff --git a/src/backend/commands/prepare.c b/src/backend/commands/prepare.c
index c0fbbabdba..0892ab9fbb 100644
--- a/src/backend/commands/prepare.c
+++ b/src/backend/commands/prepare.c
@@ -10,7 +10,7 @@
  * Copyright (c) 2002-2006, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/commands/prepare.c,v 1.49 2006/03/05 15:58:24 momjian Exp $
+ *	  $PostgreSQL: pgsql/src/backend/commands/prepare.c,v 1.50 2006/04/22 01:25:58 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -247,30 +247,30 @@ EvaluateParams(EState *estate, List *params, List *argtypes)
 	if (list_length(params) != nargs)
 		elog(ERROR, "wrong number of arguments");
 
+	if (nargs == 0)
+		return NULL;
+
 	exprstates = (List *) ExecPrepareExpr((Expr *) params, estate);
 
-	paramLI = (ParamListInfo)
-		palloc0((nargs + 1) * sizeof(ParamListInfoData));
+	/* sizeof(ParamListInfoData) includes the first array element */
+	paramLI = (ParamListInfo) palloc(sizeof(ParamListInfoData) +
+									 (nargs - 1) * sizeof(ParamExternData));
+	paramLI->numParams = nargs;
 
 	forboth(le, exprstates, la, argtypes)
 	{
 		ExprState  *n = lfirst(le);
-		bool		isNull;
+		ParamExternData *prm = &paramLI->params[i];
 
-		paramLI[i].value = ExecEvalExprSwitchContext(n,
-											  GetPerTupleExprContext(estate),
-													 &isNull,
-													 NULL);
-		paramLI[i].kind = PARAM_NUM;
-		paramLI[i].id = i + 1;
-		paramLI[i].ptype = lfirst_oid(la);
-		paramLI[i].isnull = isNull;
+		prm->ptype = lfirst_oid(la);
+		prm->value = ExecEvalExprSwitchContext(n,
+											   GetPerTupleExprContext(estate),
+											   &prm->isnull,
+											   NULL);
 
 		i++;
 	}
 
-	paramLI[i].kind = PARAM_INVALID;
-
 	return paramLI;
 }