From f07d474398e49647ff8aebfec494b447d8fc623a Mon Sep 17 00:00:00 2001
From: Michael Paquier <michael@paquier.xyz>
Date: Tue, 1 Sep 2026 08:42:53 +0900
Subject: [PATCH v3] Use pg_neg_s{16,32,64}_overflow() for some overflow checks

Extracted from a larger patch by the same author; these ones have proved
to reduce the number of instructions generated overall for clang, gcc,
with and without the builtin versions.
---
 src/backend/utils/adt/cash.c    |  9 +++++----
 src/backend/utils/adt/int.c     | 11 +++++------
 src/backend/utils/adt/int8.c    | 12 ++++--------
 src/backend/utils/adt/numeric.c |  3 +--
 4 files changed, 15 insertions(+), 20 deletions(-)

diff --git a/src/backend/utils/adt/cash.c b/src/backend/utils/adt/cash.c
index 310b3bb3fca6..0820187b8e6a 100644
--- a/src/backend/utils/adt/cash.c
+++ b/src/backend/utils/adt/cash.c
@@ -156,6 +156,8 @@ cash_mul_int64(Cash c, int64 i)
 static inline Cash
 cash_div_int64(Cash c, int64 i)
 {
+	Cash		res;
+
 	if (unlikely(i == 0))
 		ereport(ERROR,
 				(errcode(ERRCODE_DIVISION_BY_ZERO),
@@ -169,11 +171,11 @@ cash_div_int64(Cash c, int64 i)
 	 */
 	if (i == -1)
 	{
-		if (unlikely(c == PG_INT64_MIN))
+		if (pg_neg_s64_overflow(c, &res))
 			ereport(ERROR,
 					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
 					 errmsg("money out of range")));
-		return -c;
+		return res;
 	}
 
 	/* No overflow is possible */
@@ -379,12 +381,11 @@ cash_in(PG_FUNCTION_ARGS)
 	 */
 	if (sgn > 0)
 	{
-		if (value == PG_INT64_MIN)
+		if (pg_neg_s64_overflow(value, &result))
 			ereturn(escontext, (Datum) 0,
 					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
 					 errmsg("value \"%s\" is out of range for type %s",
 							str, "money")));
-		result = -value;
 	}
 	else
 		result = value;
diff --git a/src/backend/utils/adt/int.c b/src/backend/utils/adt/int.c
index 01608d8ca424..68fecbfe2ed3 100644
--- a/src/backend/utils/adt/int.c
+++ b/src/backend/utils/adt/int.c
@@ -800,12 +800,13 @@ Datum
 int4um(PG_FUNCTION_ARGS)
 {
 	int32		arg = PG_GETARG_INT32(0);
+	int32		result;
 
-	if (unlikely(arg == PG_INT32_MIN))
+	if (pg_neg_s32_overflow(arg, &result))
 		ereport(ERROR,
 				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
 				 errmsg("integer out of range")));
-	PG_RETURN_INT32(-arg);
+	PG_RETURN_INT32(result);
 }
 
 Datum
@@ -882,11 +883,10 @@ int4div(PG_FUNCTION_ARGS)
 	 */
 	if (arg2 == -1)
 	{
-		if (unlikely(arg1 == PG_INT32_MIN))
+		if (pg_neg_s32_overflow(arg1, &result))
 			ereport(ERROR,
 					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
 					 errmsg("integer out of range")));
-		result = -arg1;
 		PG_RETURN_INT32(result);
 	}
 
@@ -1140,11 +1140,10 @@ int42div(PG_FUNCTION_ARGS)
 	 */
 	if (arg2 == -1)
 	{
-		if (unlikely(arg1 == PG_INT32_MIN))
+		if (pg_neg_s32_overflow(arg1, &result))
 			ereport(ERROR,
 					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
 					 errmsg("integer out of range")));
-		result = -arg1;
 		PG_RETURN_INT32(result);
 	}
 
diff --git a/src/backend/utils/adt/int8.c b/src/backend/utils/adt/int8.c
index 1f59d831600f..1a8bddd6bb11 100644
--- a/src/backend/utils/adt/int8.c
+++ b/src/backend/utils/adt/int8.c
@@ -449,11 +449,10 @@ int8um(PG_FUNCTION_ARGS)
 	int64		arg = PG_GETARG_INT64(0);
 	int64		result;
 
-	if (unlikely(arg == PG_INT64_MIN))
+	if (pg_neg_s64_overflow(arg, &result))
 		ereport(ERROR,
 				(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
 				 errmsg("bigint out of range")));
-	result = -arg;
 	PG_RETURN_INT64(result);
 }
 
@@ -531,11 +530,10 @@ int8div(PG_FUNCTION_ARGS)
 	 */
 	if (arg2 == -1)
 	{
-		if (unlikely(arg1 == PG_INT64_MIN))
+		if (pg_neg_s64_overflow(arg1, &result))
 			ereport(ERROR,
 					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
 					 errmsg("bigint out of range")));
-		result = -arg1;
 		PG_RETURN_INT64(result);
 	}
 
@@ -991,11 +989,10 @@ int84div(PG_FUNCTION_ARGS)
 	 */
 	if (arg2 == -1)
 	{
-		if (unlikely(arg1 == PG_INT64_MIN))
+		if (pg_neg_s64_overflow(arg1, &result))
 			ereport(ERROR,
 					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
 					 errmsg("bigint out of range")));
-		result = -arg1;
 		PG_RETURN_INT64(result);
 	}
 
@@ -1133,11 +1130,10 @@ int82div(PG_FUNCTION_ARGS)
 	 */
 	if (arg2 == -1)
 	{
-		if (unlikely(arg1 == PG_INT64_MIN))
+		if (pg_neg_s64_overflow(arg1, &result))
 			ereport(ERROR,
 					(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
 					 errmsg("bigint out of range")));
-		result = -arg1;
 		PG_RETURN_INT64(result);
 	}
 
diff --git a/src/backend/utils/adt/numeric.c b/src/backend/utils/adt/numeric.c
index 523cd3cd608e..37f24e33857f 100644
--- a/src/backend/utils/adt/numeric.c
+++ b/src/backend/utils/adt/numeric.c
@@ -7870,9 +7870,8 @@ numericvar_to_int64(const NumericVar *var, int64 *result)
 
 	if (!neg)
 	{
-		if (unlikely(val == PG_INT64_MIN))
+		if (unlikely(pg_neg_s64_overflow(val, &val)))
 			return false;
-		val = -val;
 	}
 	*result = val;
 
-- 
2.55.0