Remove useless ps_OuterTupleSlot field from PlanState. I suppose this was

used long ago, but in the current code the ecxt_outertuple field of
ExprContext is doing all the work.  Spotted by Ran Tang.

src/backend/executor/nodeHashjoin.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/executor/nodeHashjoin.c,v 1.95 2008/08/15 19:20:42 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/nodeHashjoin.c,v 1.96 2008/10/23 14:34:34 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -193,7 +193,6 @@ ExecHashJoin(HashJoinState *node)
 				return NULL;
 			}
 
-			node->js.ps.ps_OuterTupleSlot = outerTupleSlot;
 			econtext->ecxt_outertuple = outerTupleSlot;
 			node->hj_NeedNewOuter = false;
 			node->hj_MatchedOuter = false;
@@ -482,7 +481,6 @@ ExecInitHashJoin(HashJoin *node, EState *estate, int eflags)
 	/* child Hash node needs to evaluate inner hash keys, too */
 	((HashState *) innerPlanState(hjstate))->hashkeys = rclauses;
 
-	hjstate->js.ps.ps_OuterTupleSlot = NULL;
 	hjstate->js.ps.ps_TupFromTlist = false;
 	hjstate->hj_NeedNewOuter = true;
 	hjstate->hj_MatchedOuter = false;
@@ -884,7 +882,6 @@ ExecReScanHashJoin(HashJoinState *node, ExprContext *exprCtxt)
 	node->hj_CurBucketNo = 0;
 	node->hj_CurTuple = NULL;
 
-	node->js.ps.ps_OuterTupleSlot = NULL;
 	node->js.ps.ps_TupFromTlist = false;
 	node->hj_NeedNewOuter = true;
 	node->hj_MatchedOuter = false;

src/backend/executor/nodeNestloop.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/executor/nodeNestloop.c,v 1.48 2008/08/15 19:20:42 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/nodeNestloop.c,v 1.49 2008/10/23 14:34:34 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -78,12 +78,6 @@ ExecNestLoop(NestLoopState *node)
 	innerPlan = innerPlanState(node);
 	econtext = node->js.ps.ps_ExprContext;
 
-	/*
-	 * get the current outer tuple
-	 */
-	outerTupleSlot = node->js.ps.ps_OuterTupleSlot;
-	econtext->ecxt_outertuple = outerTupleSlot;
-
 	/*
 	 * Check to see if we're still projecting out tuples from a previous join
 	 * tuple (because there is a function-returning-set in the projection
@@ -135,7 +129,6 @@ ExecNestLoop(NestLoopState *node)
 			}
 
 			ENL1_printf("saving new outer tuple information");
-			node->js.ps.ps_OuterTupleSlot = outerTupleSlot;
 			econtext->ecxt_outertuple = outerTupleSlot;
 			node->nl_NeedNewOuter = false;
 			node->nl_MatchedOuter = false;
@@ -357,7 +350,6 @@ ExecInitNestLoop(NestLoop *node, EState *estate, int eflags)
 	/*
 	 * finally, wipe the current outer tuple clean.
 	 */
-	nlstate->js.ps.ps_OuterTupleSlot = NULL;
 	nlstate->js.ps.ps_TupFromTlist = false;
 	nlstate->nl_NeedNewOuter = true;
 	nlstate->nl_MatchedOuter = false;
@@ -426,8 +418,6 @@ ExecReScanNestLoop(NestLoopState *node, ExprContext *exprCtxt)
 	if (outerPlan->chgParam == NULL)
 		ExecReScan(outerPlan, exprCtxt);
 
-	/* let outerPlan to free its result tuple ... */
-	node->js.ps.ps_OuterTupleSlot = NULL;
 	node->js.ps.ps_TupFromTlist = false;
 	node->nl_NeedNewOuter = true;
 	node->nl_MatchedOuter = false;

src/include/nodes/execnodes.h

@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2008, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $PostgreSQL: pgsql/src/include/nodes/execnodes.h,v 1.190 2008/10/07 19:27:04 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/nodes/execnodes.h,v 1.191 2008/10/23 14:34:34 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -868,7 +868,7 @@ typedef struct PlanState
 
 	Plan	   *plan;			/* associated Plan node */
 
-	EState	   *state;			/* at execution time, state's of individual
+	EState	   *state;			/* at execution time, states of individual
 								 * nodes point to one EState for the whole
 								 * top-level plan */
 
@@ -896,12 +896,11 @@ typedef struct PlanState
 	/*
 	 * Other run-time state needed by most if not all node types.
 	 */
-	TupleTableSlot *ps_OuterTupleSlot;	/* slot for current "outer" tuple */
 	TupleTableSlot *ps_ResultTupleSlot; /* slot for my result tuples */
 	ExprContext *ps_ExprContext;	/* node's expression-evaluation context */
 	ProjectionInfo *ps_ProjInfo;	/* info for doing tuple projection */
-	bool		ps_TupFromTlist;/* state flag for processing set-valued
-								 * functions in targetlist */
+	bool		ps_TupFromTlist;	/* state flag for processing set-valued
+									 * functions in targetlist */
 } PlanState;
 
 /* ----------------