Remove stray references to lefttree/righttree in the executor.

The general convention in the executor is to refer to child plans
and planstates via the outerPlan[State] and innerPlan[State]
macros, but a few places didn't do it like that.  For consistency
and readability, convert all the stragglers to use the macros.
(See also commit 40f42d2a3, which did some similar cleanup a few
years ago, but missed these cases.)

Richard Guo

Discussion: https://postgr.es/m/CAMbWs4-vYhh1xsa_veah4PUed2Xq=Ed_YH3=Mqt5A3Y=EgfCEg@mail.gmail.com

src/backend/executor/execAmi.c

@@ -117,11 +117,11 @@ ExecReScan(PlanState *node)
 			if (splan->plan->extParam != NULL)
 				UpdateChangedParamSet(splan, node->chgParam);
 		}
-		/* Well. Now set chgParam for left/right trees. */
-		if (node->lefttree != NULL)
-			UpdateChangedParamSet(node->lefttree, node->chgParam);
-		if (node->righttree != NULL)
-			UpdateChangedParamSet(node->righttree, node->chgParam);
+		/* Well. Now set chgParam for child trees. */
+		if (outerPlanState(node) != NULL)
+			UpdateChangedParamSet(outerPlanState(node), node->chgParam);
+		if (innerPlanState(node) != NULL)
+			UpdateChangedParamSet(innerPlanState(node), node->chgParam);
 	}
 
 	/* Call expression callbacks */

src/backend/executor/execCurrent.c

@@ -396,7 +396,7 @@ search_plan_tree(PlanState *node, Oid table_oid,
 			 */
 		case T_ResultState:
 		case T_LimitState:
-			result = search_plan_tree(node->lefttree,
+			result = search_plan_tree(outerPlanState(node),
 									  table_oid,
 									  pending_rescan);
 			break;

src/backend/executor/nodeAgg.c

@@ -3388,7 +3388,7 @@ ExecInitAgg(Agg *node, EState *estate, int eflags)
 		if (phaseidx > 0)
 		{
 			aggnode = list_nth_node(Agg, node->chain, phaseidx - 1);
-			sortnode = castNode(Sort, aggnode->plan.lefttree);
+			sortnode = castNode(Sort, outerPlan(aggnode));
 		}
 		else
 		{

src/backend/executor/nodeGather.c

@@ -168,13 +168,13 @@ ExecGather(PlanState *pstate)
 
 			/* Initialize, or re-initialize, shared state needed by workers. */
 			if (!node->pei)
-				node->pei = ExecInitParallelPlan(node->ps.lefttree,
+				node->pei = ExecInitParallelPlan(outerPlanState(node),
 												 estate,
 												 gather->initParam,
 												 gather->num_workers,
 												 node->tuples_needed);
 			else
-				ExecParallelReinitialize(node->ps.lefttree,
+				ExecParallelReinitialize(outerPlanState(node),
 										 node->pei,
 										 gather->initParam);
 

src/backend/executor/nodeGatherMerge.c

@@ -212,13 +212,13 @@ ExecGatherMerge(PlanState *pstate)
 
 			/* Initialize, or re-initialize, shared state needed by workers. */
 			if (!node->pei)
-				node->pei = ExecInitParallelPlan(node->ps.lefttree,
+				node->pei = ExecInitParallelPlan(outerPlanState(node),
 												 estate,
 												 gm->initParam,
 												 gm->num_workers,
 												 node->tuples_needed);
 			else
-				ExecParallelReinitialize(node->ps.lefttree,
+				ExecParallelReinitialize(outerPlanState(node),
 										 node->pei,
 										 gm->initParam);
 

src/backend/executor/nodeHash.c

@@ -2212,12 +2212,14 @@ ExecHashTableResetMatchFlags(HashJoinTable hashtable)
 void
 ExecReScanHash(HashState *node)
 {
+	PlanState  *outerPlan = outerPlanState(node);
+
 	/*
 	 * if chgParam of subnode is not null then plan will be re-scanned by
 	 * first ExecProcNode.
 	 */
-	if (node->ps.lefttree->chgParam == NULL)
-		ExecReScan(node->ps.lefttree);
+	if (outerPlan->chgParam == NULL)
+		ExecReScan(outerPlan);
 }
 
 

src/backend/executor/nodeHashjoin.c

@@ -1290,6 +1290,9 @@ ExecHashJoinGetSavedTuple(HashJoinState *hjstate,
 void
 ExecReScanHashJoin(HashJoinState *node)
 {
+	PlanState  *outerPlan = outerPlanState(node);
+	PlanState  *innerPlan = innerPlanState(node);
+
 	/*
 	 * In a multi-batch join, we currently have to do rescans the hard way,
 	 * primarily because batch temp files may have already been released. But
@@ -1300,7 +1303,7 @@ ExecReScanHashJoin(HashJoinState *node)
 	if (node->hj_HashTable != NULL)
 	{
 		if (node->hj_HashTable->nbatch == 1 &&
-			node->js.ps.righttree->chgParam == NULL)
+			innerPlan->chgParam == NULL)
 		{
 			/*
 			 * Okay to reuse the hash table; needn't rescan inner, either.
@@ -1328,7 +1331,7 @@ ExecReScanHashJoin(HashJoinState *node)
 		else
 		{
 			/* must destroy and rebuild hash table */
-			HashState  *hashNode = castNode(HashState, innerPlanState(node));
+			HashState  *hashNode = castNode(HashState, innerPlan);
 
 			Assert(hashNode->hashtable == node->hj_HashTable);
 			/* accumulate stats from old hash table, if wanted */
@@ -1350,8 +1353,8 @@ ExecReScanHashJoin(HashJoinState *node)
 			 * if chgParam of subnode is not null then plan will be re-scanned
 			 * by first ExecProcNode.
 			 */
-			if (node->js.ps.righttree->chgParam == NULL)
-				ExecReScan(node->js.ps.righttree);
+			if (innerPlan->chgParam == NULL)
+				ExecReScan(innerPlan);
 		}
 	}
 
@@ -1368,8 +1371,8 @@ ExecReScanHashJoin(HashJoinState *node)
 	 * if chgParam of subnode is not null then plan will be re-scanned by
 	 * first ExecProcNode.
 	 */
-	if (node->js.ps.lefttree->chgParam == NULL)
-		ExecReScan(node->js.ps.lefttree);
+	if (outerPlan->chgParam == NULL)
+		ExecReScan(outerPlan);
 }
 
 void

src/backend/executor/nodeLimit.c

@@ -542,6 +542,8 @@ ExecEndLimit(LimitState *node)
 void
 ExecReScanLimit(LimitState *node)
 {
+	PlanState  *outerPlan = outerPlanState(node);
+
 	/*
 	 * Recompute limit/offset in case parameters changed, and reset the state
 	 * machine.  We must do this before rescanning our child node, in case
@@ -553,6 +555,6 @@ ExecReScanLimit(LimitState *node)
 	 * if chgParam of subnode is not null then plan will be re-scanned by
 	 * first ExecProcNode.
 	 */
-	if (node->ps.lefttree->chgParam == NULL)
-		ExecReScan(node->ps.lefttree);
+	if (outerPlan->chgParam == NULL)
+		ExecReScan(outerPlan);
 }

src/backend/executor/nodeLockRows.c

@@ -394,10 +394,12 @@ ExecEndLockRows(LockRowsState *node)
 void
 ExecReScanLockRows(LockRowsState *node)
 {
+	PlanState  *outerPlan = outerPlanState(node);
+
 	/*
 	 * if chgParam of subnode is not null then plan will be re-scanned by
 	 * first ExecProcNode.
 	 */
-	if (node->ps.lefttree->chgParam == NULL)
-		ExecReScan(node->ps.lefttree);
+	if (outerPlan->chgParam == NULL)
+		ExecReScan(outerPlan);
 }

src/backend/executor/nodeMergejoin.c

@@ -1658,6 +1658,9 @@ ExecEndMergeJoin(MergeJoinState *node)
 void
 ExecReScanMergeJoin(MergeJoinState *node)
 {
+	PlanState  *outerPlan = outerPlanState(node);
+	PlanState  *innerPlan = innerPlanState(node);
+
 	ExecClearTuple(node->mj_MarkedTupleSlot);
 
 	node->mj_JoinState = EXEC_MJ_INITIALIZE_OUTER;
@@ -1670,8 +1673,8 @@ ExecReScanMergeJoin(MergeJoinState *node)
 	 * if chgParam of subnodes is not null then plans will be re-scanned by
 	 * first ExecProcNode.
 	 */
-	if (node->js.ps.lefttree->chgParam == NULL)
-		ExecReScan(node->js.ps.lefttree);
-	if (node->js.ps.righttree->chgParam == NULL)
-		ExecReScan(node->js.ps.righttree);
+	if (outerPlan->chgParam == NULL)
+		ExecReScan(outerPlan);
+	if (innerPlan->chgParam == NULL)
+		ExecReScan(innerPlan);
 }

src/backend/executor/nodeProjectSet.c

@@ -339,6 +339,8 @@ ExecEndProjectSet(ProjectSetState *node)
 void
 ExecReScanProjectSet(ProjectSetState *node)
 {
+	PlanState  *outerPlan = outerPlanState(node);
+
 	/* Forget any incompletely-evaluated SRFs */
 	node->pending_srf_tuples = false;
 
@@ -346,6 +348,6 @@ ExecReScanProjectSet(ProjectSetState *node)
 	 * If chgParam of subnode is not null then plan will be re-scanned by
 	 * first ExecProcNode.
 	 */
-	if (node->ps.lefttree->chgParam == NULL)
-		ExecReScan(node->ps.lefttree);
+	if (outerPlan->chgParam == NULL)
+		ExecReScan(outerPlan);
 }

src/backend/executor/nodeResult.c

@@ -259,6 +259,8 @@ ExecEndResult(ResultState *node)
 void
 ExecReScanResult(ResultState *node)
 {
+	PlanState  *outerPlan = outerPlanState(node);
+
 	node->rs_done = false;
 	node->rs_checkqual = (node->resconstantqual != NULL);
 
@@ -266,7 +268,6 @@ ExecReScanResult(ResultState *node)
 	 * If chgParam of subnode is not null then plan will be re-scanned by
 	 * first ExecProcNode.
 	 */
-	if (node->ps.lefttree &&
-		node->ps.lefttree->chgParam == NULL)
-		ExecReScan(node->ps.lefttree);
+	if (outerPlan && outerPlan->chgParam == NULL)
+		ExecReScan(outerPlan);
 }

src/backend/executor/nodeSetOp.c

@@ -597,6 +597,8 @@ ExecEndSetOp(SetOpState *node)
 void
 ExecReScanSetOp(SetOpState *node)
 {
+	PlanState  *outerPlan = outerPlanState(node);
+
 	ExecClearTuple(node->ps.ps_ResultTupleSlot);
 	node->setop_done = false;
 	node->numOutput = 0;
@@ -617,7 +619,7 @@ ExecReScanSetOp(SetOpState *node)
 		 * parameter changes, then we can just rescan the existing hash table;
 		 * no need to build it again.
 		 */
-		if (node->ps.lefttree->chgParam == NULL)
+		if (outerPlan->chgParam == NULL)
 		{
 			ResetTupleHashIterator(node->hashtable, &node->hashiter);
 			return;
@@ -646,6 +648,6 @@ ExecReScanSetOp(SetOpState *node)
 	 * if chgParam of subnode is not null then plan will be re-scanned by
 	 * first ExecProcNode.
 	 */
-	if (node->ps.lefttree->chgParam == NULL)
-		ExecReScan(node->ps.lefttree);
+	if (outerPlan->chgParam == NULL)
+		ExecReScan(outerPlan);
 }

src/backend/executor/nodeUnique.c

@@ -180,6 +180,8 @@ ExecEndUnique(UniqueState *node)
 void
 ExecReScanUnique(UniqueState *node)
 {
+	PlanState  *outerPlan = outerPlanState(node);
+
 	/* must clear result tuple so first input tuple is returned */
 	ExecClearTuple(node->ps.ps_ResultTupleSlot);
 
@@ -187,6 +189,6 @@ ExecReScanUnique(UniqueState *node)
 	 * if chgParam of subnode is not null then plan will be re-scanned by
 	 * first ExecProcNode.
 	 */
-	if (node->ps.lefttree->chgParam == NULL)
-		ExecReScan(node->ps.lefttree);
+	if (outerPlan->chgParam == NULL)
+		ExecReScan(outerPlan);
 }