--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/pr89795.c	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,25 @@
+/* PR rtl-optimization/89795 */
+/* { dg-do run } */
+/* { dg-options "-O2 -fno-dce -fno-forward-propagate -fno-sched-pressure" } */
+
+unsigned char a;
+unsigned b, c, d;
+
+int
+main ()
+{
+#if __CHAR_BIT__ == 8
+  unsigned x;
+  int e, f;
+  unsigned char g;
+  e = __builtin_bswap32 (a);
+  f = __builtin_ffs (~(unsigned short) e);
+  a = __builtin_mul_overflow ((unsigned char) 0xf7, f, &g);
+  a |= __builtin_sub_overflow_p (c, 0, (unsigned char) 0);
+  d = g + b;
+  x = d;
+  if (x != 0xf7)
+    __builtin_abort ();
+#endif
+  return 0;
+}