psql.diff

diff --git a/src/include/utils/sortsupport.h b/src/include/utils/sortsupport.h
index 8c36cf8d82..e1d209cb66 100644
--- a/src/include/utils/sortsupport.h
+++ b/src/include/utils/sortsupport.h
@@ -193,15 +193,11 @@ typedef struct SortSupportData
 
 
 /*
- * Apply a sort comparator function and return a 3-way comparison result.
- * This takes care of handling reverse-sort and NULLs-ordering properly.
+ * The common isNull1 or isNull2 case for all the Apply.*Sort() below.
  */
-static inline int
-ApplySortComparator(Datum datum1, bool isNull1,
-					Datum datum2, bool isNull2,
-					SortSupport ssup)
+static inline void _SortComparatorNull(bool isNull1, bool isNull2, int *comparep)
 {
-	int			compare;
+	int compare;
 
 	if (isNull1)
 	{
@@ -219,6 +215,30 @@ ApplySortComparator(Datum datum1, bool isNull1,
 		else
 			compare = -1;		/* NOT_NULL "<" NULL */
 	}
+	else
+	{
+		abort(); // unreachable
+	}
+
+	*comparep = compare;
+}
+
+
+/*
+ * Apply a sort comparator function and return a 3-way comparison result.
+ * This takes care of handling reverse-sort and NULLs-ordering properly.
+ */
+static inline int
+ApplySortComparator(Datum datum1, bool isNull1,
+					Datum datum2, bool isNull2,
+					SortSupport ssup)
+{
+	int			compare;
+
+	if (isNull1 || isNull2)
+	{
+		_SortComparatorNull(isNull1, isNull2, &compare);
+    }
 	else
 	{
 		compare = ssup->comparator(datum1, datum2, ssup);
@@ -236,22 +256,10 @@ ApplyUnsignedSortComparator(Datum datum1, bool isNull1,
 {
 	int			compare;
 
-	if (isNull1)
-	{
-		if (isNull2)
-			compare = 0;		/* NULL "=" NULL */
-		else if (ssup->ssup_nulls_first)
-			compare = -1;		/* NULL "<" NOT_NULL */
-		else
-			compare = 1;		/* NULL ">" NOT_NULL */
-	}
-	else if (isNull2)
+	if (isNull1 || isNull2)
 	{
-		if (ssup->ssup_nulls_first)
-			compare = 1;		/* NOT_NULL ">" NULL */
-		else
-			compare = -1;		/* NOT_NULL "<" NULL */
-	}
+		_SortComparatorNull(isNull1, isNull2, &compare);
+    }
 	else
 	{
 		compare = datum1 < datum2 ? -1 : datum1 > datum2 ? 1 : 0;
@@ -305,22 +313,10 @@ ApplyInt32SortComparator(Datum datum1, bool isNull1,
 {
 	int			compare;
 
-	if (isNull1)
-	{
-		if (isNull2)
-			compare = 0;		/* NULL "=" NULL */
-		else if (ssup->ssup_nulls_first)
-			compare = -1;		/* NULL "<" NOT_NULL */
-		else
-			compare = 1;		/* NULL ">" NOT_NULL */
-	}
-	else if (isNull2)
+	if (isNull1 || isNull2)
 	{
-		if (ssup->ssup_nulls_first)
-			compare = 1;		/* NOT_NULL ">" NULL */
-		else
-			compare = -1;		/* NOT_NULL "<" NULL */
-	}
+		_SortComparatorNull(isNull1, isNull2, &compare);
+    }
 	else
 	{
 		compare = DatumGetInt32(datum1) < DatumGetInt32(datum2) ? -1 :
@@ -344,22 +340,10 @@ ApplySortAbbrevFullComparator(Datum datum1, bool isNull1,
 {
 	int			compare;
 
-	if (isNull1)
+	if (isNull1 || isNull2)
 	{
-		if (isNull2)
-			compare = 0;		/* NULL "=" NULL */
-		else if (ssup->ssup_nulls_first)
-			compare = -1;		/* NULL "<" NOT_NULL */
-		else
-			compare = 1;		/* NULL ">" NOT_NULL */
-	}
-	else if (isNull2)
-	{
-		if (ssup->ssup_nulls_first)
-			compare = 1;		/* NOT_NULL ">" NULL */
-		else
-			compare = -1;		/* NOT_NULL "<" NULL */
-	}
+		_SortComparatorNull(isNull1, isNull2, &compare);
+    }
 	else
 	{
 		compare = ssup->abbrev_full_comparator(datum1, datum2, ssup);