On 04/11/2024 20:34, Torbjorn SVENSSON wrote:
>
>
> On 2024-11-04 17:03, Richard Earnshaw (lists) wrote:
>> On 31/10/2024 18:26, Torbjörn SVENSSON wrote:
>>> Ok for trunk and releases/gcc-14?
>>>
>>> --
>>>
>>> Tests uses neon, so add effective-target arm_neon.
>>>
>>> gcc/testsuite/ChangeLog:
>>>
>>> * gcc.target/arm/pr68620.c: Use effective-target arm_neon.
>>> * gcc.target/arm/pr78041.c: Likewise.
>>>
>>> Signed-off-by: Torbjörn SVENSSON <torbjorn.svens...@foss.st.com>
>>> ---
>>> gcc/testsuite/gcc.target/arm/pr68620.c | 4 ++--
>>> gcc/testsuite/gcc.target/arm/pr78041.c | 3 ++-
>>> 2 files changed, 4 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/gcc/testsuite/gcc.target/arm/pr68620.c
>>> b/gcc/testsuite/gcc.target/arm/pr68620.c
>>> index 91878432b00..b4a44dab6ba 100644
>>> --- a/gcc/testsuite/gcc.target/arm/pr68620.c
>>> +++ b/gcc/testsuite/gcc.target/arm/pr68620.c
>>> @@ -1,8 +1,8 @@
>>> /* { dg-do compile } */
>>> /* { dg-skip-if "-mpure-code supports M-profile without Neon only" {
>>> *-*-* } { "-mpure-code" } } */
>>> -/* { dg-require-effective-target arm_fp_ok } */
>>> +/* { dg-require-effective-target arm_neon_ok } */
>>
>> This seems reasonable, but ...
>>
>>> /* { dg-options "-mfp16-format=ieee" } */
>>> -/* { dg-add-options arm_fp } */
>>> +/* { dg-add-options arm_neon } */
>>> #include "arm_neon.h"
>>>
>>
>> ... I don't think this is right. It looks like the point of this test is to
>> check that adding the #pragma to select a neon-based FPU enables a specific
>> intrinsic. That ought to work with the existing checks (at least, modulo
>> changing the effective-target at the start). But adding neon options on the
>> command line shouldn't be needed. What's the option combination that leads
>> to a failure?
>
> The arm_fp is not enough to ensure a valid architecture is in use.
>
> If I do not switch from arm_fp to arm_neon, I get the test executed like this
> for m85hard:
>
> .../bin/arm-none-eabi-gcc .../gcc/testsuite/gcc.target/arm/pr68620.c -mthumb
> -march=armv8.1-m.main+mve -mcpu=cortex-m55 -mfloat-abi=hard -mfpu=fpv5-d16
> -fdiagnostics-plain-output -mfp16-format=ieee -S -o pr68620.s
>
> Obvious, -mfp16-format=ieee is valid for Cortex-M85, but it's not the same
> thing as that it supports neon/nenon-fp16. The check for arm_neon passes as
> there are flags that could be added that override and makes the check pass,
> i.e.:
>
> .../bin/arm-none-eabi-gcc -mthumb -march=armv8.1-m.main+mve
> -mcpu=cortex-m55 -mfloat-abi=hard -mfpu=fpv5-d16 -fdiagnostics-plain-output
> -mfpu=neon -mfloat-abi=softfp -mcpu=unset -march=armv7-a
> -Wno-complain-wrong-lang -c -o arm_neon_ok16723.o arm_neon_ok16723.c
>
>
> Note: I get this when I am adding -mcpu=unset to the arm_neon_ok check. If I
> do not add the -mcpu=unset, the test is marked as unsupported due to a
> conflicting -march/-mcpu combination (this is what I'm trying to fix in the
> patchset that I will share in a few days, but without a dedicated fix, these
> tests will be listed as regressions).
>
>
> So, in order for the test to pass, a compatible architecture must be selected
> and if we are not going to use the arm_neon check, then what should we us to
> get as wide coverage as possible?
This is similar to the other neon tests I've just replied about: I'd just skip
this (pr68620) test on m-profile for now.
R.
>
> Kind regards,
> Torbjörn
