re PR tree-optimization/71423 (wrong code at -Os and above on x86_64-linux-gnu)

2016-06-07  Richard Biener  <rguenther@suse.de>

	PR middle-end/71423
	* match.pd ((X | ~Y) -> Y <= X): Properly invert the comparison
	for signed ops.

	* gcc.dg/torture/pr71423.c: New testcase.

From-SVN: r237166

gcc/ChangeLog

+2016-06-07  Richard Biener  <rguenther@suse.de>
+
+	PR middle-end/71423
+	* match.pd ((X | ~Y) -> Y <= X): Properly invert the comparison
+	for signed ops.
+
 2016-06-06  John David Anglin  <danglin@gcc.gnu.org>
 
 	* config/pa/pa.md (call): Generate indirect long calls to non-local

gcc/match.pd

@@ -900,12 +900,16 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
   (ne (bit_and:c (bit_not @0) @1) integer_zerop)
   (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
        && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
-   (lt @0 @1)))
+   (if (TYPE_UNSIGNED (TREE_TYPE (@1)))
+    (lt @0 @1)
+    (gt @0 @1))))
 (simplify
   (ne (bit_ior:c (bit_not @0) @1) integer_zerop)
   (if (INTEGRAL_TYPE_P (TREE_TYPE (@1))
        && TYPE_PRECISION (TREE_TYPE (@1)) == 1)
-   (le @0 @1)))
+   (if (TYPE_UNSIGNED (TREE_TYPE (@1)))
+    (le @0 @1)
+    (ge @0 @1))))
 
 /* ~~x -> x */
 (simplify

gcc/testsuite/ChangeLog

+2016-06-07  Richard Biener  <rguenther@suse.de>
+
+	PR middle-end/71423
+	* gcc.dg/torture/pr71423.c: New testcase.
+
 2016-06-07  Kugan Vivekanandarajah  <kuganv@linaro.org>
 
 	PR middle-end/71408

gcc/testsuite/gcc.dg/torture/pr71423.c

+/* { dg-do run } */
+
+struct S1
+{
+  int f1:1;
+};
+
+volatile struct S1 b = { 0 };
+
+int
+main ()
+{
+  char c = b.f1;
+  b.f1 = 1; 
+
+  if (b.f1 > -1 || c)
+    __builtin_abort (); 
+
+  return 0; 
+}