Get rid of the separate EState for subplans, and just let them share the

parent query's EState.  Now that there's a single flat rangetable for both
the main plan and subplans, there's no need anymore for a separate EState,
and removing it allows cleaning up some crufty code in nodeSubplan.c and
nodeSubqueryscan.c.  Should be a tad faster too, although any difference
will probably be hard to measure.  This is the last bit of subsidiary
mop-up work from changing to a flat rangetable.

1 files changed, 7 insertions, 42 deletions

diff --git a/src/backend/executor/execUtils.c b/src/backend/executor/execUtils.c
index d188a38489d..493df3ef9ac 100644
--- a/src/backend/executor/execUtils.c
+++ b/src/backend/executor/execUtils.c
@@ -8,14 +8,13 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/executor/execUtils.c,v 1.146 2007/02/22 22:00:22 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/execUtils.c,v 1.147 2007/02/27 01:11:25 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
 /*
  * INTERFACE ROUTINES
  *		CreateExecutorState		Create/delete executor working state
- *		CreateSubExecutorState
  *		FreeExecutorState
  *		CreateExprContext
  *		CreateStandaloneExprContext
@@ -66,8 +65,6 @@ int			NIndexTupleInserted;
 int			NIndexTupleProcessed;
 
 
-static EState *InternalCreateExecutorState(MemoryContext qcontext,
-										   bool is_subquery);
 static void ShutdownExprContext(ExprContext *econtext);
 
 
@@ -152,7 +149,9 @@ DisplayTupleCount(FILE *statfp)
 EState *
 CreateExecutorState(void)
 {
+	EState	   *estate;
 	MemoryContext qcontext;
+	MemoryContext oldcontext;
 
 	/*
 	 * Create the per-query context for this Executor run.
@@ -163,37 +162,6 @@ CreateExecutorState(void)
 									 ALLOCSET_DEFAULT_INITSIZE,
 									 ALLOCSET_DEFAULT_MAXSIZE);
 
-	return InternalCreateExecutorState(qcontext, false);
-}
-
-/* ----------------
- *		CreateSubExecutorState
- *
- *		Create and initialize an EState node for a sub-query.
- *
- * Ideally, sub-queries probably shouldn't have their own EState at all,
- * but right now this is necessary because they have their own rangetables
- * and we access the rangetable via the EState.  It is critical that a
- * sub-query share the parent's es_query_cxt, else structures allocated by
- * the sub-query (especially its result tuple descriptor) may disappear
- * too soon during executor shutdown.
- * ----------------
- */
-EState *
-CreateSubExecutorState(EState *parent_estate)
-{
-	return InternalCreateExecutorState(parent_estate->es_query_cxt, true);
-}
-
-/*
- * Guts of CreateExecutorState/CreateSubExecutorState
- */
-static EState *
-InternalCreateExecutorState(MemoryContext qcontext, bool is_subquery)
-{
-	EState	   *estate;
-	MemoryContext oldcontext;
-
 	/*
 	 * Make the EState node within the per-query context.  This way, we don't
 	 * need a separate pfree() operation for it at shutdown.
@@ -232,14 +200,14 @@ InternalCreateExecutorState(MemoryContext qcontext, bool is_subquery)
 	estate->es_lastoid = InvalidOid;
 	estate->es_rowMarks = NIL;
 
-	estate->es_is_subquery = is_subquery;
-
 	estate->es_instrument = false;
 	estate->es_select_into = false;
 	estate->es_into_oids = false;
 
 	estate->es_exprcontexts = NIL;
 
+	estate->es_subplanstates = NIL;
+
 	estate->es_per_tuple_exprcontext = NULL;
 
 	estate->es_plannedstmt = NULL;
@@ -292,12 +260,9 @@ FreeExecutorState(EState *estate)
 
 	/*
 	 * Free the per-query memory context, thereby releasing all working
-	 * memory, including the EState node itself.  In a subquery, we don't
-	 * do this, leaving the memory cleanup to happen when the topmost query
-	 * is closed down.
+	 * memory, including the EState node itself.
 	 */
-	if (!estate->es_is_subquery)
-		MemoryContextDelete(estate->es_query_cxt);
+	MemoryContextDelete(estate->es_query_cxt);
 }
 
 /* ----------------