Attachment 37956 Details for Bug 70222 – gcc6-pr70222.patch

gcc6-pr70222.patch

gcc6-pr70222.patch (text/plain), 1.67 KB, created by Jakub Jelinek on 2016-03-14 13:06:59 UTC

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Creator: Jakub Jelinek

Created: 2016-03-14 13:06:59 UTC

Size: 1.67 KB

patch

obsolete

>2016-03-14  Jakub Jelinek  <jakub@redhat.com>
>
>	PR rtl-optimization/70222
>	* combine.c (simplify_shift_const_1): Force simplify_and_const_int
>	for LSHIFTRT if result_mode != mode && count == 0.
>
>	* gcc.c-torture/execute/pr70222.c: New test.
>
>--- gcc/combine.c.jj	2016-02-11 23:52:57.000000000 +0100
>+++ gcc/combine.c	2016-03-14 14:00:24.576657458 +0100
>@@ -10835,8 +10835,12 @@ simplify_shift_const_1 (enum rtx_code co
>     x = simplify_gen_binary (code, shift_mode, varop, GEN_INT (count));
> 
>   /* If we were doing an LSHIFTRT in a wider mode than it was originally,
>-     turn off all the bits that the shift would have turned off.  */
>-  if (orig_code == LSHIFTRT && result_mode != shift_mode)
>+     turn off all the bits that the shift would have turned off.
>+     Similarly do this if if we've optimized varop so that we don't perform
>+     any shift.  */
>+  if (orig_code == LSHIFTRT
>+      && (result_mode != shift_mode
>+	  || (result_mode != mode && count == 0)))
>     x = simplify_and_const_int (NULL_RTX, shift_mode, x,
> 				GET_MODE_MASK (result_mode) >> orig_count);
> 
>--- gcc/testsuite/gcc.c-torture/execute/pr70222.c.jj	2016-03-14 14:03:27.998140364 +0100
>+++ gcc/testsuite/gcc.c-torture/execute/pr70222.c	2016-03-14 14:03:12.000000000 +0100
>@@ -0,0 +1,30 @@
>+/* PR rtl-optimization/70222 */
>+
>+int a = 1;
>+unsigned int b = 2;
>+int c = 0;
>+int d = 0;
>+
>+void
>+foo ()
>+{
>+  int e = ((-(c >= c)) < b) > ((int) (-1ULL >> ((a / a) * 15)));
>+  d = -e;
>+}
>+
>+__attribute__((noinline, noclone)) void
>+bar (int x)
>+{
>+  if (x != -1)
>+    __builtin_abort ();
>+}
>+
>+int
>+main ()
>+{
>+#if __CHAR_BIT__ == 8 && __SIZEOF_INT__ == 4 && __SIZEOF_LONG_LONG__ == 8
>+  foo ();
>+  bar (d);
>+#endif
>+  return 0;
>+}

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