On Tue, Aug 25, 2026 at 10:38 AM Dipesh Sharma <[email protected]> wrote:
>
> Hi Maintainers,
>
> Bootstrapped and tested on x86_64-linux, Ok to backport to GCC 16.x branch ??
>
> Regards,
> Dipesh
>
> - Moved bit_AVX512BMM to extended features section.
> - Added test for __builtin_cpu_supports ("avx512bmm") compile and runtime
> tests.
>
> gcc/ChangeLog:
>
> * common/config/i386/cpuinfo.h (get_available_features): Detect
> AVX512BMM from
> extended features instead of standard leaf.
> * config/i386/cpuid.h (bit_AVX512BMM): Move to extended features
> section.
>
> gcc/testsuite/ChangeLog:
>
> * gcc.target/i386/avx512bmm-check-1.c: New test.
> * gcc.target/i386/avx512bmm-check-2.c: New test.
> * gcc.target/i386/avx512bmm-check-3.c: New test.
OK.
Thanks,
Uros.
>
> (cherry picked from commit 33053605189f2b903b1a0d730a1feec166e89735)
> ---
> gcc/common/config/i386/cpuinfo.h | 16 +++------------
> gcc/config/i386/cpuid.h | 4 +---
> .../gcc.target/i386/avx512bmm-check-1.c | 6 ++++++
> .../gcc.target/i386/avx512bmm-check-2.c | 20 +++++++++++++++++++
> .../gcc.target/i386/avx512bmm-check-3.c | 6 ++++++
> 5 files changed, 36 insertions(+), 16 deletions(-)
> create mode 100644 gcc/testsuite/gcc.target/i386/avx512bmm-check-1.c
> create mode 100644 gcc/testsuite/gcc.target/i386/avx512bmm-check-2.c
> create mode 100644 gcc/testsuite/gcc.target/i386/avx512bmm-check-3.c
>
> diff --git a/gcc/common/config/i386/cpuinfo.h
> b/gcc/common/config/i386/cpuinfo.h
> index f59090c8cde..e07d01991ca 100644
> --- a/gcc/common/config/i386/cpuinfo.h
> +++ b/gcc/common/config/i386/cpuinfo.h
> @@ -1112,16 +1112,6 @@ 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)
> {
> @@ -1196,9 +1186,9 @@ get_available_features (struct __processor_model
> *cpu_model,
> {
> __cpuid (0x80000021, eax, ebx, ecx, edx);
> if (eax & bit_AMD_PREFETCHI)
> - {
> - set_feature (FEATURE_PREFETCHI);
> - }
> + set_feature (FEATURE_PREFETCHI);
> + if (eax & bit_AVX512BMM)
> + set_feature (FEATURE_AVX512BMM);
> }
>
> #undef set_feature
> diff --git a/gcc/config/i386/cpuid.h b/gcc/config/i386/cpuid.h
> index c48556afa6e..0b5e6cc99a0 100644
> --- a/gcc/config/i386/cpuid.h
> +++ b/gcc/config/i386/cpuid.h
> @@ -75,6 +75,7 @@
> /* Extended Features (%eax == 0x80000021) */
> /* %eax */
> #define bit_AMD_PREFETCHI (1 << 20)
> +#define bit_AVX512BMM (1 << 23)
>
> /* Extended Features Leaf (%eax == 7, %ecx == 0) */
> /* %ebx */
> @@ -167,9 +168,6 @@
> #define bit_AESKLE ( 1<<0 )
> #define bit_WIDEKL ( 1<<2 )
>
> -/* Sub leaf (%eax == 0x21) */
> -#define bit_AVX512BMM ( 1<<23 )
> -
> /* AMX sub leaf (%eax == 0x1e, %ecx == 1) */
> /* %eax */
> #define bit_AMX_FP8 (1 << 4)
> diff --git a/gcc/testsuite/gcc.target/i386/avx512bmm-check-1.c
> b/gcc/testsuite/gcc.target/i386/avx512bmm-check-1.c
> new file mode 100644
> index 00000000000..176b06eb09a
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/i386/avx512bmm-check-1.c
> @@ -0,0 +1,6 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -march=znver6" } */
> +
> +#ifndef __AVX512BMM__
> +# error AVX512BMM should be enabled for target znver6.
> +#endif
> diff --git a/gcc/testsuite/gcc.target/i386/avx512bmm-check-2.c
> b/gcc/testsuite/gcc.target/i386/avx512bmm-check-2.c
> new file mode 100644
> index 00000000000..956ae2d2acb
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/i386/avx512bmm-check-2.c
> @@ -0,0 +1,20 @@
> +/* { dg-do run } */
> +/* { dg-options "-O2 -march=native" } */
> +
> +int
> +main ()
> +{
> + if (__builtin_cpu_supports ("avx512bmm"))
> + {
> +#ifndef __AVX512BMM__
> + __builtin_abort ();
> +#endif
> + }
> + else
> + {
> +#ifdef __AVX512BMM__
> + __builtin_abort ();
> +#endif
> + }
> + return 0;
> +}
> diff --git a/gcc/testsuite/gcc.target/i386/avx512bmm-check-3.c
> b/gcc/testsuite/gcc.target/i386/avx512bmm-check-3.c
> new file mode 100644
> index 00000000000..25ffeb8c87b
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/i386/avx512bmm-check-3.c
> @@ -0,0 +1,6 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -march=native -mno-avx512bmm" } */
> +
> +#if defined(__ZNVER6__) && defined(__AVX512BMM__)
> +# error AVX512BMM should be disabled for native detection of target znver6
> with -mno-avx512bmm.
> +#endif
> --
> 2.34.1
>
