1 files changed, 132 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/builtin-arith-overflow-1.c b/gcc/testsuite/gcc.dg/builtin-arith-overflow-1.c
new file mode 100644
index 0000000..b9c1517
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/builtin-arith-overflow-1.c
@@ -0,0 +1,132 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -fdump-tree-optimized -g" } */
+
+/* SUB_OVERFLOW should be folded into unsigned subtraction,
+   because ovf is never used.  */
+__attribute__((noinline, noclone)) int
+fn1 (int x, unsigned int y)
+{
+  int res;
+  int ovf = __builtin_sub_overflow (x, y, &res);
+  int res2 = res;
+  int res3 = res2 - 2;
+  (void) ovf;
+  return res;
+}
+
+/* MUL_OVERFLOW should be folded into unsigned multiplication,
+   because ovf is never used.  */
+__attribute__((noinline, noclone)) int
+fn2 (char x, long int y)
+{
+  short int res;
+  int ovf = __builtin_mul_overflow (x, y, &res);
+  int res2 = res;
+  int res3 = res2 - 2;
+  (void) ovf;
+  return res;
+}
+
+#if __SIZEOF_INT__ > __SIZEOF_SHORT__ && __SIZEOF_INT__ > 1
+/* ADD_OVERFLOW should be folded into unsigned addition,
+   because it never overflows.  */
+__attribute__((noinline, noclone)) int
+fn3 (char x, unsigned short y, int *ovf)
+{
+  int res;
+  *ovf = __builtin_add_overflow (x, y, &res);
+  return res;
+}
+#endif
+
+/* MUL_OVERFLOW should be folded into unsigned multiplication,
+   because it never overflows.  */
+__attribute__((noinline, noclone)) long int
+fn4 (long int x, long int y, int *ovf)
+{
+  long int res;
+  x &= 65535;
+  y = (y & 65535) - 32768;
+  *ovf = __builtin_mul_overflow (x, y, &res);
+  return res;
+}
+
+#if __SIZEOF_INT__ > 1
+/* MUL_OVERFLOW should be folded into unsigned multiplication,
+   because it always overflows.  */
+__attribute__((noinline, noclone)) signed char
+fn5 (long int x, long int y, int *ovf)
+{
+  signed char res;
+  x = (x & 63) + (__SCHAR_MAX__ / 4);
+  y = (y & 3) + 5;
+  *ovf = __builtin_mul_overflow (x, y, &res);
+  return res;
+}
+#endif
+
+/* ADD_OVERFLOW should be folded into unsigned additrion,
+   because it never overflows.  */
+__attribute__((noinline, noclone)) unsigned char
+fn6 (unsigned char x, unsigned char y, int *ovf)
+{
+  unsigned char res;
+  x = (x & 63) + ((unsigned char) ~0 - 66);
+  y = (y & 3);
+  *ovf = __builtin_add_overflow (x, y, &res);
+  return res;
+}
+
+/* ADD_OVERFLOW should be folded into unsigned additrion,
+   because it always overflows.  */
+__attribute__((noinline, noclone)) unsigned char
+fn7 (unsigned char x, unsigned char y, int *ovf)
+{
+  unsigned char res;
+  x = (x & 15) + ((unsigned char) ~0 - 15);
+  y = (y & 3) + 16;
+  *ovf = __builtin_add_overflow (x, y, &res);
+  return res;
+}
+
+int
+main ()
+{
+  int ovf;
+  if (fn1 (-10, __INT_MAX__) != (int) (-10U - __INT_MAX__)
+      || fn2 (0, 0) != 0
+      || fn2 (32, 16383) != (short int) 524256ULL)
+    __builtin_abort ();
+#if __SIZEOF_INT__ > __SIZEOF_SHORT__ && __SIZEOF_INT__ > 1
+  if (fn3 (__SCHAR_MAX__, (unsigned short) ~0, &ovf) != (int) (__SCHAR_MAX__ + (unsigned short) ~0)
+      || ovf
+      || fn3 (-__SCHAR_MAX__ - 1, 0, &ovf) != (int) (-__SCHAR_MAX__ - 1)
+      || ovf)
+    __builtin_abort ();
+#endif
+  if (fn4 (65535, 0, &ovf) != 65535L * -32768 || ovf)
+    __builtin_abort ();
+#if __SIZEOF_INT__ > 1
+  if (fn5 (0, 0, &ovf) != (signed char) (__SCHAR_MAX__ / 4 * 5)
+      || !ovf
+      || fn5 (63, 3, &ovf) != (signed char) ((__SCHAR_MAX__ / 4 + 63) * 8)
+      || !ovf)
+    __builtin_abort ();
+#endif
+  if (fn6 (0, 0, &ovf) != (unsigned char) ~0 - 66
+      || ovf
+      || fn6 (63, 3, &ovf) != (unsigned char) ~0
+      || ovf)
+    __builtin_abort ();
+  if (fn7 (0, 0, &ovf) != 0
+      || !ovf
+      || fn7 (63, 3, &ovf) != 18
+      || !ovf)
+    __builtin_abort ();
+  return 0;
+}
+
+/* { dg-final { scan-tree-dump-not "ADD_OVERFLOW" "optimized" } } */
+/* { dg-final { scan-tree-dump-not "SUB_OVERFLOW" "optimized" } } */
+/* { dg-final { scan-tree-dump-not "MUL_OVERFLOW" "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */