Re: [PATCH 14/19] <sys/platform/x86.h>: Add AVX-IFMA support

[Noah Goldstein <goldstein.w.n@gmail.com>]

On Wed, Apr 5, 2023 at 11:27 AM H.J. Lu via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>
> Add AVX-IFMA support to <sys/platform/x86.h>.
> ---
>  manual/platform.texi               | 3 +++
>  sysdeps/x86/bits/platform/x86.h    | 1 +
>  sysdeps/x86/cpu-features.c         | 2 ++
>  sysdeps/x86/include/cpu-features.h | 3 +++
>  sysdeps/x86/tst-get-cpu-features.c | 2 ++
>  5 files changed, 11 insertions(+)
>
> diff --git a/manual/platform.texi b/manual/platform.texi
> index 7d4aa3d339..af75e5c413 100644
> --- a/manual/platform.texi
> +++ b/manual/platform.texi
> @@ -219,6 +219,9 @@ Leaf (EAX = 23H).
>  @item
>  @code{AVX2} -- The AVX2 instruction extensions.
>
> +@item
> +@code{AVX_IFMA} -- The AVX-IFMA instruction extensions.
> +
>  @item
>  @code{AVX_VNNI} -- The AVX-VNNI instruction extensions.
>
> diff --git a/sysdeps/x86/bits/platform/x86.h b/sysdeps/x86/bits/platform/x86.h
> index 2776c69b16..abc0116607 100644
> --- a/sysdeps/x86/bits/platform/x86.h
> +++ b/sysdeps/x86/bits/platform/x86.h
> @@ -300,6 +300,7 @@ enum
>    x86_cpu_WRMSRNS              = x86_cpu_index_7_ecx_1_eax + 19,
>    x86_cpu_AMX_FP16             = x86_cpu_index_7_ecx_1_eax + 21,
>    x86_cpu_HRESET               = x86_cpu_index_7_ecx_1_eax + 22,
> +  x86_cpu_AVX_IFMA             = x86_cpu_index_7_ecx_1_eax + 23,
>    x86_cpu_LAM                  = x86_cpu_index_7_ecx_1_eax + 26,
>
>    x86_cpu_index_19_ebx
> diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
> index 6c1b5efc5f..06fae443a8 100644
> --- a/sysdeps/x86/cpu-features.c
> +++ b/sysdeps/x86/cpu-features.c
> @@ -139,6 +139,8 @@ update_active (struct cpu_features *cpu_features)
>                   cpu_features->preferred[index_arch_AVX_Fast_Unaligned_Load]
>                     |= bit_arch_AVX_Fast_Unaligned_Load;
>                 }
> +             /* Determine if AVX-IFMA is usable.  */
> +             CPU_FEATURE_SET_ACTIVE (cpu_features, AVX_IFMA);
>               /* Determine if AVX-VNNI is usable.  */
>               CPU_FEATURE_SET_ACTIVE (cpu_features, AVX_VNNI);
>               /* Determine if FMA is usable.  */
> diff --git a/sysdeps/x86/include/cpu-features.h b/sysdeps/x86/include/cpu-features.h
> index 07c841c1d4..1f4b6831f9 100644
> --- a/sysdeps/x86/include/cpu-features.h
> +++ b/sysdeps/x86/include/cpu-features.h
> @@ -311,6 +311,7 @@ enum
>  #define bit_cpu_FSRCS          (1u << 12)
>  #define bit_cpu_AMX_FP16       (1u << 21)
>  #define bit_cpu_HRESET         (1u << 22)
> +#define bit_cpu_AVX_IFMA       (1u << 23)
>  #define bit_cpu_LAM            (1u << 26)
>
>  /* CPUID_INDEX_19.  */
> @@ -549,6 +550,7 @@ enum
>  #define index_cpu_FSRCS                CPUID_INDEX_7_ECX_1
>  #define index_cpu_AMX_FP16     CPUID_INDEX_7_ECX_1
>  #define index_cpu_HRESET       CPUID_INDEX_7_ECX_1
> +#define index_cpu_AVX_IFMA     CPUID_INDEX_7_ECX_1
>  #define index_cpu_LAM          CPUID_INDEX_7_ECX_1
>
>  /* CPUID_INDEX_19.  */
> @@ -787,6 +789,7 @@ enum
>  #define reg_FSRCS              eax
>  #define reg_AMX_FP16           eax
>  #define reg_HRESET             eax
> +#define reg_AVX_IFMA           eax
>  #define reg_LAM                        eax
>
>  /* CPUID_INDEX_19.  */
> diff --git a/sysdeps/x86/tst-get-cpu-features.c b/sysdeps/x86/tst-get-cpu-features.c
> index c0f222cb77..3a2d4671ec 100644
> --- a/sysdeps/x86/tst-get-cpu-features.c
> +++ b/sysdeps/x86/tst-get-cpu-features.c
> @@ -212,6 +212,7 @@ do_test (void)
>    CHECK_CPU_FEATURE_PRESENT (WRMSRNS);
>    CHECK_CPU_FEATURE_PRESENT (AMX_FP16);
>    CHECK_CPU_FEATURE_PRESENT (HRESET);
> +  CHECK_CPU_FEATURE_PRESENT (AVX_IFMA);
>    CHECK_CPU_FEATURE_PRESENT (LAM);
>    CHECK_CPU_FEATURE_PRESENT (AESKLE);
>    CHECK_CPU_FEATURE_PRESENT (WIDE_KL);
> @@ -379,6 +380,7 @@ do_test (void)
>    CHECK_CPU_FEATURE_ACTIVE (FSRS);
>    CHECK_CPU_FEATURE_ACTIVE (FSRCS);
>    CHECK_CPU_FEATURE_ACTIVE (AMX_FP16);
> +  CHECK_CPU_FEATURE_ACTIVE (AVX_IFMA);
>    CHECK_CPU_FEATURE_ACTIVE (AESKLE);
>    CHECK_CPU_FEATURE_ACTIVE (WIDE_KL);
>    CHECK_CPU_FEATURE_ACTIVE (PTWRITE);
> --
> 2.39.2
>

LGTM
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>