Add test case for PR 110405

PR was fixed bu one of the other patches.

	* gcc.dg/pr110405.c: New.

gcc/testsuite/gcc.dg/pr110405.c

@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+void foo (unsigned long);
+void
+f (unsigned long i)
+{
+  if ((i & 7) == 6)
+    if(i & 1)
+      foo (0);
+}
+
+/* { dg-final { scan-tree-dump-not "foo"  "optimized" } } */
+