diff --git a/src/backend/nodes/bitmapset.c b/src/backend/nodes/bitmapset.c
index c927b78..daec9e6 100644
--- a/src/backend/nodes/bitmapset.c
+++ b/src/backend/nodes/bitmapset.c
@@ -525,6 +525,61 @@ bms_singleton_member(const Bitmapset *a)
 }
 
 /*
+ * bms_get_singleton
+ *
+ * Returns True and sets singleton to the value of the singleton, if the
+ * bitmapset is a singleton, otherwise, if the bitmapset is NULL, empty or has
+ * multiple values, False is returned.
+ *
+ * This function can be useful if some processing only needs to take place
+ * when a Bitmapset is a singleton and that singleton value is required for
+ * that processing, for example, you could do:
+ *
+ * if (bms_membership(a) != BMS_SINGLETON)
+ *		return; // nothing to do
+ * singleton = bms_singleton_member(a);
+ *
+ * But it would be more efficiently processed by doing:
+ *
+ * if (!bms_get_singleton(a, &singleton))
+ *		return; // nothing to do
+ */
+bool
+bms_get_singleton(const Bitmapset *a, int *singleton)
+{
+	int			result = -1;
+	int			nwords;
+	int			wordnum;
+
+	if (a == NULL)
+		return false;
+	nwords = a->nwords;
+	for (wordnum = 0; wordnum < nwords; wordnum++)
+	{
+		bitmapword	w = a->words[wordnum];
+
+		if (w != 0)
+		{
+			if (result >= 0 || HAS_MULTIPLE_ONES(w))
+				return false;
+			result = wordnum * BITS_PER_BITMAPWORD;
+			while ((w & 255) == 0)
+			{
+				w >>= 8;
+				result += 8;
+			}
+			result += rightmost_one_pos[w & 255];
+		}
+	}
+	if (result < 0)
+		return false;
+
+	*singleton = result;
+	return true;
+}
+
+
+/*
  * bms_num_members - count members of set
  */
 int
diff --git a/src/backend/optimizer/path/equivclass.c b/src/backend/optimizer/path/equivclass.c
index 63dbc1b..0d7722b 100644
--- a/src/backend/optimizer/path/equivclass.c
+++ b/src/backend/optimizer/path/equivclass.c
@@ -937,9 +937,9 @@ generate_base_implied_equalities_no_const(PlannerInfo *root,
 		int			relid;
 
 		Assert(!cur_em->em_is_child);	/* no children yet */
-		if (bms_membership(cur_em->em_relids) != BMS_SINGLETON)
+		if (!bms_get_singleton(cur_em->em_relids, &relid))
 			continue;
-		relid = bms_singleton_member(cur_em->em_relids);
+
 		Assert(relid < root->simple_rel_array_size);
 
 		if (prev_ems[relid] != NULL)
diff --git a/src/backend/optimizer/plan/analyzejoins.c b/src/backend/optimizer/plan/analyzejoins.c
index b0a11d7..e906cd3 100644
--- a/src/backend/optimizer/plan/analyzejoins.c
+++ b/src/backend/optimizer/plan/analyzejoins.c
@@ -207,10 +207,9 @@ leftjoin_is_removable(PlannerInfo *root, SpecialJoinInfo *sjinfo)
 	 * going to be able to do anything with it.
 	 */
 	if (sjinfo->delay_upper_joins ||
-		bms_membership(sjinfo->min_righthand) != BMS_SINGLETON)
+		!bms_get_singleton(sjinfo->min_righthand, &innerrelid))
 		return false;
 
-	innerrelid = bms_singleton_member(sjinfo->min_righthand);
 	innerrel = find_base_rel(root, innerrelid);
 
 	if (innerrel->reloptkind != RELOPT_BASEREL)
@@ -489,10 +488,9 @@ semiorantijoin_is_removable(PlannerInfo *root, SpecialJoinInfo *sjinfo,
 	 * checking the right hand rel has any indexes.
 	 */
 	if (sjinfo->delay_upper_joins ||
-		bms_membership(sjinfo->min_lefthand) != BMS_SINGLETON)
+		!bms_get_singleton(sjinfo->min_lefthand, &outerrelid))
 		return false;
 
-	outerrelid = bms_singleton_member(sjinfo->min_lefthand);
 	outerrel = find_base_rel(root, outerrelid);
 
 	/*
@@ -504,10 +502,9 @@ semiorantijoin_is_removable(PlannerInfo *root, SpecialJoinInfo *sjinfo,
 		outerrel->fklist == NIL)
 		return false;
 
-	if (bms_membership(sjinfo->min_righthand) != BMS_SINGLETON)
+	if (!bms_get_singleton(sjinfo->min_righthand, &innerrelid))
 		return false;
 
-	innerrelid = bms_singleton_member(sjinfo->min_righthand);
 	innerrel = find_base_rel(root, innerrelid);
 
 	/*
diff --git a/src/backend/optimizer/util/placeholder.c b/src/backend/optimizer/util/placeholder.c
index 8d7c4fe..d9d1c6a 100644
--- a/src/backend/optimizer/util/placeholder.c
+++ b/src/backend/optimizer/util/placeholder.c
@@ -383,10 +383,10 @@ add_placeholders_to_base_rels(PlannerInfo *root)
 	{
 		PlaceHolderInfo *phinfo = (PlaceHolderInfo *) lfirst(lc);
 		Relids		eval_at = phinfo->ph_eval_at;
+		int			varno;
 
-		if (bms_membership(eval_at) == BMS_SINGLETON)
+		if (bms_get_singleton(eval_at, &varno))
 		{
-			int			varno = bms_singleton_member(eval_at);
 			RelOptInfo *rel = find_base_rel(root, varno);
 
 			/* add it to reltargetlist if needed above the rel scan level */
diff --git a/src/include/nodes/bitmapset.h b/src/include/nodes/bitmapset.h
index f770608..6db7270 100644
--- a/src/include/nodes/bitmapset.h
+++ b/src/include/nodes/bitmapset.h
@@ -72,6 +72,8 @@ extern bool bms_is_member(int x, const Bitmapset *a);
 extern bool bms_overlap(const Bitmapset *a, const Bitmapset *b);
 extern bool bms_nonempty_difference(const Bitmapset *a, const Bitmapset *b);
 extern int	bms_singleton_member(const Bitmapset *a);
+extern bool bms_get_singleton(const Bitmapset *a, int *singleton);
+
 extern int	bms_num_members(const Bitmapset *a);
 
 /* optimized tests when we don't need to know exact membership count: */