Re: [PATCH] math: x86: Remove extra '%' on FP_INIT_ROUNDMODE inline asm

[Adhemerval Zanella Netto <adhemerval.zanella@linaro.org>]

On 31/08/22 16:33, H.J. Lu wrote:
> On Wed, Aug 31, 2022 at 11:16 AM Adhemerval Zanella via Libc-alpha
> <libc-alpha@sourceware.org> wrote:
>>
>> Checked on x86_64-linux-gnu.
>> ---
>>  sysdeps/x86/fpu/sfp-machine.h | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/sysdeps/x86/fpu/sfp-machine.h b/sysdeps/x86/fpu/sfp-machine.h
>> index 5892f4f5fe..1cacdb4ebd 100644
>> --- a/sysdeps/x86/fpu/sfp-machine.h
>> +++ b/sysdeps/x86/fpu/sfp-machine.h
>> @@ -41,7 +41,7 @@ typedef unsigned int UTItype __attribute__ ((mode (TI)));
>>
>>  # define FP_INIT_ROUNDMODE                                     \
>>    do {                                                         \
>> -    __asm__ __volatile__ ("%vstmxcsr\t%0" : "=m" (_fcw));      \
>> +    __asm__ __volatile__ ("vstmxcsr\t%0" : "=m" (_fcw));       \
>>    } while (0)
>>  #else
>>  # define _FP_W_TYPE_SIZE       32
>> --
>> 2.34.1
>>
> 
> The intention was to generate stmxcsr with SSE and vstmxcsr with
> AVX.  I think we should define a special prefix, like AVX_INSN_PREFIX,
> which is 'v' if __AVX__ is defined and empty if __AVX__ isn't defined.
> 

Right, I was not aware of it.  Is is documented on gcc inline assembly
manual somewhere (I could not find it)? In any case I will follow your
suggestion.