On Fri, Aug 21, 2026 at 2:34 AM Dipesh Sharma <[email protected]> wrote:
>
> Hi,
>
> This patch fixes the AVX512BMM cpuid check for zen6. The AVX512BMM is
> present in the extended features instead of the standard leaf.
Where is AVX512BMM spec? It should also be supported by
glibc.
> bootstraped and regtested on x86_64-linux-gnu. Ok for trunk ?
>
> gcc/ChangeLog:
>
> * common/config/i386/cpuinfo.h (get_available_features): Detect
> AVXBMM from extended features instead of standard leaf.
> ---
> gcc/common/config/i386/cpuinfo.h | 12 ++----------
> 1 file changed, 2 insertions(+), 10 deletions(-)
>
> diff --git a/gcc/common/config/i386/cpuinfo.h
> b/gcc/common/config/i386/cpuinfo.h
> index fef8f90f94c..153ab194864 100644
> --- a/gcc/common/config/i386/cpuinfo.h
> +++ b/gcc/common/config/i386/cpuinfo.h
> @@ -1110,16 +1110,6 @@ get_available_features (struct __processor_model
> *cpu_model,
> }
> }
>
> - /* Get Advanced Features at level 0x21 (eax = 0x21). */
> - if (max_cpuid_level >= 0x21)
> - {
> - __cpuid (0x21, eax, ebx, ecx, edx);
> - if (eax & bit_AVX512BMM)
> - {
> - set_feature (FEATURE_AVX512BMM);
> - }
> - }
> -
> /* Get Advanced Features at level 0x24 (eax = 0x24, ecx = 0). */
> if (avx10_set && max_cpuid_level >= 0x24)
> {
> @@ -1205,6 +1195,8 @@ get_available_features (struct __processor_model
> *cpu_model,
> {
> set_feature (FEATURE_PREFETCHI);
> }
> + if (eax & bit_AVX512BMM)
> + set_feature (FEATURE_AVX512BMM);
> }
>
> #undef set_feature
> --
> 2.34.1
>
--
H.J.
