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

["Kewen.Lin" <linkw@linux.ibm.com>]

Hi,

on 2024/4/22 18:00, Alexandre Oliva wrote:
> 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.  */

OK, though the proposed comment is slightly different from what's in
the related commit r8-6445-g86145a19abf39f. :)  Thanks!

BR,
Kewen

>  /* { dg-add-options ieee } */
>  /* { dg-require-effective-target fenv_exceptions } */
>  /* { dg-skip-if "fenv" { powerpc-ibm-aix* } } */
> 
>