diff mbox series

Fix up 20181120-1.c testcase on big-endian (PR rtl-optimization/85925, take 2)

Message ID 20181121191244.GR11625@tucnak
State New
Headers show
Series Fix up 20181120-1.c testcase on big-endian (PR rtl-optimization/85925, take 2) | expand

Commit Message

Jakub Jelinek Nov. 21, 2018, 7:12 p.m. UTC 
Hi!

On Wed, Nov 21, 2018 at 12:07:51PM -0600, Segher Boessenkool wrote:
> > Admittedly, it might be better if the initializer was 0x1010101 or say
> > 0x4030201 because on big endian in particular 0x10101 has the top 15 bits
> > all zero and thus that is what is in u.f1, so if the bug can be reproduced
> > with the combine.c + rtlanal.c fix reverted with 0x4030201, it would be
> > better to use that value (in both spots).
> 
> Yeah good point.

I've now managed to test this with a cross to armv7hl (scped to an arm box)
with and without the rtlanal.c + combine.c change reverted and on
powerpc64-linux as example of big-endian, on armv7hl it still fails with
the changes reverted, otherwise it succeeds on both.  The test also needs
32-bit int target (previously just 17-bit or more, so I've added effective
target).

Ok for trunk and release branches?

2018-11-21  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/85925
	* gcc.c-torture/execute/20181120-1.c: Require effective target
	int32plus.
	(u): New variable.
	(main): Compare d against u.f1 rather than 0x101.  Use 0x4030201
	instead of 0x10101.



	Jakub

Comments

Segher Boessenkool Nov. 21, 2018, 8:37 p.m. UTC | #1 
On Wed, Nov 21, 2018 at 08:12:44PM +0100, Jakub Jelinek wrote:
> On Wed, Nov 21, 2018 at 12:07:51PM -0600, Segher Boessenkool wrote:
> > > Admittedly, it might be better if the initializer was 0x1010101 or say
> > > 0x4030201 because on big endian in particular 0x10101 has the top 15 bits
> > > all zero and thus that is what is in u.f1, so if the bug can be reproduced
> > > with the combine.c + rtlanal.c fix reverted with 0x4030201, it would be
> > > better to use that value (in both spots).
> > 
> > Yeah good point.
> 
> I've now managed to test this with a cross to armv7hl (scped to an arm box)
> with and without the rtlanal.c + combine.c change reverted and on
> powerpc64-linux as example of big-endian, on armv7hl it still fails with
> the changes reverted, otherwise it succeeds on both.  The test also needs
> 32-bit int target (previously just 17-bit or more, so I've added effective
> target).

It fixes the problem on powerpc64-linux {-m32,-m64}.  Thanks :-)


Segher
diff mbox series

Patch

--- gcc/testsuite/gcc.c-torture/execute/20181120-1.c.jj	2018-11-21 17:39:47.963671708 +0100
+++ gcc/testsuite/gcc.c-torture/execute/20181120-1.c	2018-11-21 20:07:45.804556443 +0100
@@ -1,4 +1,5 @@ 
 /* PR rtl-optimization/85925 */
+/* { dg-require-effective-target int32plus } */
 /* Testcase by <sudi@gcc.gnu.org> */
 
 int a, c, d;
@@ -9,17 +10,18 @@  union U1 {
   unsigned f0;
   unsigned f1 : 15;
 };
+volatile union U1 u = { 0x4030201 };
 
 int main (void)
 {
   for (c = 0; c <= 1; c++) {
-    union U1 f = {0x10101};
+    union U1 f = {0x4030201};
     if (c == 1)
       b;
     *e = f.f1;
   }
 
-  if (d != 0x101)
+  if (d != u.f1)
     __builtin_abort ();
 
   return 0;