Revert "Move PartitionPruneInfo out of plan nodes into PlannedStmt"

This reverts commit ec38694894 and its fixup 589bb81649.

This change was intended to support query planning avoiding acquisition
of locks on partitions that were going to be pruned; however, the
overall project took a different direction at [1] and this bit is no
longer needed.  Put things back the way they were as agreed in [2], to
avoid unnecessary complexity.

Discussion: [1] https://postgr.es/m/4191508.1674157166@sss.pgh.pa.us
Discussion: [2] https://postgr.es/m/20230502175409.kcoirxczpdha26wt@alvherre.pgsql

src/backend/executor/execMain.c

@@ -824,7 +824,6 @@ InitPlan(QueryDesc *queryDesc, int eflags)
 	ExecInitRangeTable(estate, rangeTable, plannedstmt->permInfos);
 
 	estate->es_plannedstmt = plannedstmt;
-	estate->es_part_prune_infos = plannedstmt->partPruneInfos;
 
 	/*
 	 * Next, build the ExecRowMark array from the PlanRowMark(s), if any.

src/backend/executor/execParallel.c

@@ -183,7 +183,6 @@ ExecSerializePlan(Plan *plan, EState *estate)
 	pstmt->dependsOnRole = false;
 	pstmt->parallelModeNeeded = false;
 	pstmt->planTree = plan;
-	pstmt->partPruneInfos = estate->es_part_prune_infos;
 	pstmt->rtable = estate->es_range_table;
 	pstmt->permInfos = estate->es_rteperminfos;
 	pstmt->resultRelations = NIL;

src/backend/executor/execPartition.c

@@ -1778,9 +1778,6 @@ adjust_partition_colnos_using_map(List *colnos, AttrMap *attrMap)
  *		Initialize data structure needed for run-time partition pruning and
  *		do initial pruning if needed
  *
- * 'root_parent_relids' identifies the relation to which both the parent plan
- * and the PartitionPruneInfo given by 'part_prune_index' belong.
- *
  * On return, *initially_valid_subplans is assigned the set of indexes of
  * child subplans that must be initialized along with the parent plan node.
  * Initial pruning is performed here if needed and in that case only the
@@ -1793,24 +1790,11 @@ adjust_partition_colnos_using_map(List *colnos, AttrMap *attrMap)
 PartitionPruneState *
 ExecInitPartitionPruning(PlanState *planstate,
 						 int n_total_subplans,
-						 int part_prune_index,
-						 Bitmapset *root_parent_relids,
+						 PartitionPruneInfo *pruneinfo,
 						 Bitmapset **initially_valid_subplans)
 {
 	PartitionPruneState *prunestate;
 	EState	   *estate = planstate->state;
-	PartitionPruneInfo *pruneinfo;
-
-	/* Obtain the pruneinfo we need, and make sure it's the right one */
-	pruneinfo = list_nth(estate->es_part_prune_infos, part_prune_index);
-	if (!bms_equal(root_parent_relids, pruneinfo->root_parent_relids))
-		ereport(ERROR,
-				errcode(ERRCODE_INTERNAL_ERROR),
-				errmsg_internal("mismatching PartitionPruneInfo found at part_prune_index %d",
-								part_prune_index),
-				errdetail_internal("plan node relids %s, pruneinfo relids %s",
-								   bmsToString(root_parent_relids),
-								   bmsToString(pruneinfo->root_parent_relids)));
 
 	/* We may need an expression context to evaluate partition exprs */
 	ExecAssignExprContext(estate, planstate);

src/backend/executor/execUtils.c

@@ -123,7 +123,6 @@ CreateExecutorState(void)
 	estate->es_rowmarks = NULL;
 	estate->es_rteperminfos = NIL;
 	estate->es_plannedstmt = NULL;
-	estate->es_part_prune_infos = NIL;
 
 	estate->es_junkFilter = NULL;
 

src/backend/executor/nodeAppend.c

@@ -134,7 +134,7 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
 	appendstate->as_begun = false;
 
 	/* If run-time partition pruning is enabled, then set that up now */
-	if (node->part_prune_index >= 0)
+	if (node->part_prune_info != NULL)
 	{
 		PartitionPruneState *prunestate;
 
@@ -145,8 +145,7 @@ ExecInitAppend(Append *node, EState *estate, int eflags)
 		 */
 		prunestate = ExecInitPartitionPruning(&appendstate->ps,
 											  list_length(node->appendplans),
-											  node->part_prune_index,
-											  node->apprelids,
+											  node->part_prune_info,
 											  &validsubplans);
 		appendstate->as_prune_state = prunestate;
 		nplans = bms_num_members(validsubplans);

src/backend/executor/nodeMergeAppend.c

@@ -82,7 +82,7 @@ ExecInitMergeAppend(MergeAppend *node, EState *estate, int eflags)
 	mergestate->ps.ExecProcNode = ExecMergeAppend;
 
 	/* If run-time partition pruning is enabled, then set that up now */
-	if (node->part_prune_index >= 0)
+	if (node->part_prune_info != NULL)
 	{
 		PartitionPruneState *prunestate;
 
@@ -93,8 +93,7 @@ ExecInitMergeAppend(MergeAppend *node, EState *estate, int eflags)
 		 */
 		prunestate = ExecInitPartitionPruning(&mergestate->ps,
 											  list_length(node->mergeplans),
-											  node->part_prune_index,
-											  node->apprelids,
+											  node->part_prune_info,
 											  &validsubplans);
 		mergestate->ms_prune_state = prunestate;
 		nplans = bms_num_members(validsubplans);