On 20-02-15 10:42, Jakub Jelinek wrote:
On Fri, Feb 20, 2015 at 10:25:54AM +0100, Tom de Vries wrote:
this patch reverses the abort logic in pr30957-1.c, such that it aborts on
failure rather than on success.
That sounds really weird. From the description it looks like it is a known bug
that we don't return -0.0.
If 0.0 is the right return value instead, I'd the test should be written as
if (__builtin_copysignf (1.0, foo (0.0 / -5.0, 10)) != 1.0)
abort ();
to make it clear you are expecting positive 0.
Updated patch accordingly. OK for stage1?
Thanks,
- Tom
2015-02-20 Tom de Vries <t...@codesourcery.com>
* gcc.dg/pr30957-1.c: Make pr30957-1.c pass rather xfail.
---
gcc/testsuite/gcc.dg/pr30957-1.c | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)
diff --git a/gcc/testsuite/gcc.dg/pr30957-1.c b/gcc/testsuite/gcc.dg/pr30957-1.c
index 65b98fa..0ed150d 100644
--- a/gcc/testsuite/gcc.dg/pr30957-1.c
+++ b/gcc/testsuite/gcc.dg/pr30957-1.c
@@ -1,10 +1,6 @@
-/* { dg-do run { xfail *-*-* } } */
-/* We don't (and don't want to) perform this optimisation on soft-float
- targets, where each addition is a library call. This test requires
- -fassociative-math for enabling the variable-expansion as well as
- -fsigned-zeros for honoring the sign of zero; but
- they can not co-exist; also under -funsafe-math-optimizations, so we
- expect it to fail. */
+/* { dg-do run } */
+/* We don't (and don't want to) perform this optimisation on soft-float targets,
+ where each addition is a library call. /
/* { dg-require-effective-target hard_float } */
/* { dg-options "-O2 -funroll-loops -funsafe-math-optimizations -fvariable-expansion-in-unroller -fdump-rtl-loop2_unroll" } */
@@ -26,12 +22,14 @@ foo (float d, int n)
int
main ()
{
- if (__builtin_copysignf (1.0, foo (0.0 / -5.0, 10)) != -1.0)
+ /* When compiling standard compliant we expect foo to return -0.0. But the
+ variable expansion during unrolling optimization (for this testcase enabled
+ by -funsafe-math-optimization) instantiates copy(s) of the accumulator
+ which it initializes with +0.0. Hence we expect that foo returns +0.0. */
+ if (__builtin_copysignf (1.0, foo (0.0 / -5.0, 10)) != 1.0)
abort ();
exit (0);
}
/* { dg-final { scan-rtl-dump "Expanding Accumulator" "loop2_unroll" } } */
/* { dg-final { cleanup-rtl-dump "loop*" } } */
-
-
--
1.9.1
