[PATCH v2] xfail fetestexcept test - ppc always uses fcmpu

[Alexandre Oliva <oliva@adacore.com>]

On Mar 10, 2021, Joseph Myers <joseph@codesourcery.com> wrote:

> On Wed, 10 Mar 2021, Alexandre Oliva wrote:
>> operand exception for quiet NaN.  I couldn't find any evidence that
>> the rs6000 backend ever outputs fcmpo.  Therefore, I'm adding the same
>> execution xfail marker to this test.

> In my view, such an XFAIL (for a GCC bug as opposed to an environmental 
> issue) should have a comment pointing to a corresponding open bug in GCC 
> Bugzilla.  In this case, that's bug 58684.

Thanks for the suggestion, yeah, that makes sense.  Fixed in v2 below.
https://gcc.gnu.org/pipermail/gcc-patches/2021-March/566523.html
Ping?-ish


gcc.dg/torture/pr91323.c tests that a compare with NaNf doesn't set an
exception using builtin compare intrinsics, and that it does when
using regular compare operators.

That doesn't seem to be expected to work on powerpc targets.  It fails
on GNU/Linux, it's marked to be skipped on AIX, and a similar test,
gcc.dg/torture/pr93133.c, has the execution test xfailed for all of
powerpc*-*-*.

In this test, the functions that use intrinsics for the compare end up
with the same code as the one that uses compare operators, using
fcmpu, a floating compare that, unlike fcmpo, does not set the invalid
operand exception for quiet NaN.  I couldn't find any evidence that
the rs6000 backend ever outputs fcmpo.  Therefore, I'm adding the same
execution xfail marker to this test.

Regstrapped on x86_64-linux-gnu and ppc64el-linux-gnu.  Also tested with
gcc-13 on ppc64-vx7r2 and ppc-vx7r2.  Ok to install?


for  gcc/testsuite/ChangeLog

	PR target/58684
	* gcc.dg/torture/pr91323.c: Expect execution fail on
	powerpc*-*-*.
---
 gcc/testsuite/gcc.dg/torture/pr91323.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gcc/testsuite/gcc.dg/torture/pr91323.c b/gcc/testsuite/gcc.dg/torture/pr91323.c
index 1411fcaa3966c..f188faa3ccf47 100644
--- a/gcc/testsuite/gcc.dg/torture/pr91323.c
+++ b/gcc/testsuite/gcc.dg/torture/pr91323.c
@@ -1,4 +1,5 @@
-/* { dg-do run } */
+/* { dg-do run { xfail powerpc*-*-* } } */
+/* The ppc xfail is because of PR target/58684.  */
 /* { dg-add-options ieee } */
 /* { dg-require-effective-target fenv_exceptions } */
 /* { dg-skip-if "fenv" { powerpc-ibm-aix* } } */


-- 
Alexandre Oliva, happy hacker            https://FSFLA.org/blogs/lxo/
   Free Software Activist                   GNU Toolchain Engineer
More tolerance and less prejudice are key for inclusion and diversity
Excluding neuro-others for not behaving ""normal"" is *not* inclusive