diff --git a/src/backend/optimizer/plan/createplan.c b/src/backend/optimizer/plan/createplan.c
index 8baf36ba4b7..81e16e87d62 100644
--- a/src/backend/optimizer/plan/createplan.c
+++ b/src/backend/optimizer/plan/createplan.c
@@ -4344,6 +4344,7 @@ create_nestloop_plan(PlannerInfo *root,
 	NestLoop   *join_plan;
 	Plan	   *outer_plan;
 	Plan	   *inner_plan;
+	Relids		outerrelids;
 	List	   *tlist = build_path_tlist(root, &best_path->jpath.path);
 	List	   *joinrestrictclauses = best_path->jpath.joinrestrictinfo;
 	List	   *joinclauses;
@@ -4374,8 +4375,8 @@ create_nestloop_plan(PlannerInfo *root,
 	outer_plan = create_plan_recurse(root, best_path->jpath.outerjoinpath, 0);
 
 	/* For a nestloop, include outer relids in curOuterRels for inner side */
-	root->curOuterRels = bms_union(root->curOuterRels,
-								   best_path->jpath.outerjoinpath->parent->relids);
+	outerrelids = best_path->jpath.outerjoinpath->parent->relids;
+	root->curOuterRels = bms_union(root->curOuterRels, outerrelids);
 
 	inner_plan = create_plan_recurse(root, best_path->jpath.innerjoinpath, 0);
 
@@ -4415,7 +4416,8 @@ create_nestloop_plan(PlannerInfo *root,
 	 * node, and remove them from root->curOuterParams.
 	 */
 	nestParams = identify_current_nestloop_params(root,
-												  best_path->jpath.outerjoinpath);
+												  outerrelids,
+												  PATH_REQ_OUTER((Path *) best_path));
 
 	/*
 	 * While nestloop parameters that are Vars had better be available from
@@ -4423,6 +4425,10 @@ create_nestloop_plan(PlannerInfo *root,
 	 * that are PHVs won't be.  In such cases we must add them to the
 	 * outer_plan's tlist, since the executor's NestLoopParam machinery
 	 * requires the params to be simple outer-Var references to that tlist.
+	 * (This is cheating a little bit, because the outer path's required-outer
+	 * relids might not be enough to allow evaluating such a PHV.  But in
+	 * practice, if we could have evaluated the PHV at the nestloop node, we
+	 * can do so in the outer plan too.)
 	 */
 	outer_tlist = outer_plan->targetlist;
 	outer_parallel_safe = outer_plan->parallel_safe;
diff --git a/src/backend/optimizer/util/paramassign.c b/src/backend/optimizer/util/paramassign.c
index 9836abf9479..5403ae89eab 100644
--- a/src/backend/optimizer/util/paramassign.c
+++ b/src/backend/optimizer/util/paramassign.c
@@ -599,9 +599,10 @@ process_subquery_nestloop_params(PlannerInfo *root, List *subplan_params)
 }
 
 /*
- * Identify any NestLoopParams that should be supplied by a NestLoop plan
- * node with the specified lefthand input path.  Remove them from the active
- * root->curOuterParams list and return them as the result list.
+ * Identify any NestLoopParams that should be supplied by a NestLoop
+ * plan node with the specified lefthand rels and required-outer rels.
+ * Remove them from the active root->curOuterParams list and return
+ * them as the result list.
  *
  * XXX Here we also hack up the returned Vars and PHVs so that they do not
  * contain nullingrel sets exceeding what is available from the outer side.
@@ -626,11 +627,11 @@ process_subquery_nestloop_params(PlannerInfo *root, List *subplan_params)
  * subquery, which'd be unduly expensive.
  */
 List *
-identify_current_nestloop_params(PlannerInfo *root, Path *leftpath)
+identify_current_nestloop_params(PlannerInfo *root,
+								 Relids leftrelids,
+								 Relids outerrelids)
 {
 	List	   *result;
-	Relids		leftrelids = leftpath->parent->relids;
-	Relids		outerrelids = PATH_REQ_OUTER(leftpath);
 	Relids		allleftrelids;
 	ListCell   *cell;
 
diff --git a/src/include/optimizer/paramassign.h b/src/include/optimizer/paramassign.h
index d30d20de299..bbf7214289b 100644
--- a/src/include/optimizer/paramassign.h
+++ b/src/include/optimizer/paramassign.h
@@ -30,7 +30,8 @@ extern Param *replace_nestloop_param_placeholdervar(PlannerInfo *root,
 extern void process_subquery_nestloop_params(PlannerInfo *root,
 											 List *subplan_params);
 extern List *identify_current_nestloop_params(PlannerInfo *root,
-											  Path *leftpath);
+											  Relids leftrelids,
+											  Relids outerrelids);
 extern Param *generate_new_exec_param(PlannerInfo *root, Oid paramtype,
 									  int32 paramtypmod, Oid paramcollation);
 extern int	assign_special_exec_param(PlannerInfo *root);