Re: [PING 6][PATCH v3] rs6000/p8swap: Fix incorrect lane extraction by vec_extract() [PR106770]

On 8/18/26 7:02 AM, Surya Kumari Jangala wrote:
> On 20/05/26 11:53 AM, Michael Meissner wrote:
>> Note, the tests are rather tricky, and I believe they will not work
>> correctly if you configure the compiler to default to power9, power10,
>> or power11 code.
>>
>> The test has the guard condition:
>>
>> /* { dg-require-effective-target powerpc_p8vector_ok } */
>> /* { dg-options "-mdejagnu-cpu=power8 -O2 " } */
>>
>> What -mdejagnu-cpu=power8 does is tell the test compiler to use
>> -mcpu=power8 if the default target is not at the power8 level.  If you
>> configure the compiler to default to power9, power10, or power11, using
>> -mdejagnu-cpu=power8 will not change the default.
> 
> I built a compiler with --with-cpu=power10. And with this compiler if I
> run a test that specifies -mdejagnu-cpu=power8, this option is honoured and power8
> assembly is generated.
> Am I missing something?

You are not missing anything and what you describe is the designed behavior.
If you use -mdejagnu-cpu=XXX regardless of the default, you will get code emitted
for cpu XXX.

Peter