--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/gcc.dg/pr88784-10.c	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,32 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+#include <limits.h>
+
+_Bool or1(unsigned x, unsigned y)
+{
+  /* x <= y || x != 0 --> true */
+  return x <= y || x != 0;
+}
+
+_Bool or2(unsigned x, unsigned y)
+{
+  /* x >= y || x != UINT_MAX --> true */
+  return x >= y || x != UINT_MAX;
+}
+
+_Bool or3(signed x, signed y)
+{
+  /* x <= y || x != INT_MIN --> true */
+  return x <= y || x != INT_MIN;
+}
+
+_Bool or4(signed x, signed y)
+{
+  /* x >= y || x != INT_MAX --> true */
+  return x >= y || x != INT_MAX;
+}
+
+/* { dg-final { scan-tree-dump-not " != " "optimized" } } */
+/* { dg-final { scan-tree-dump-not " <= " "optimized" } } */
+/* { dg-final { scan-tree-dump-not " >= " "optimized" } } */