[FFmpeg-devel] [PATCH v3] libavutil/ppc: Make use of getauxval() and elf_aux_info() on ppc

[Brad Smith]

ping.

On 2024-09-15 1:40 a.m., Brad Smith wrote:
> libavutil/ppc: Make use of getauxval() and elf_aux_info() on ppc
>
> Modern Linux has getauxval() and FreeBSD/OpenBSD ppc have elf_aux_info().
>
> Signed-off-by: Brad Smith <brad at comstyle.com>
> ---
> v2: adjust to build with older glibc.
> v3: freebsd/ppc requires machine/cpu.h header for feature flags.
>
>   libavutil/ppc/cpu.c | 25 +++++++++++++++++++++++++
>   1 file changed, 25 insertions(+)
>
> diff --git a/libavutil/ppc/cpu.c b/libavutil/ppc/cpu.c
> index 2b13cda662..9381272175 100644
> --- a/libavutil/ppc/cpu.c
> +++ b/libavutil/ppc/cpu.c
> @@ -20,6 +20,11 @@
>   
>   #ifdef __APPLE__
>   #include <sys/sysctl.h>
> +#elif HAVE_GETAUXVAL || HAVE_ELF_AUX_INFO
> +#ifdef __FreeBSD__
> +#include <machine/cpu.h>
> +#endif
> +#include <sys/auxv.h>
>   #elif defined(__linux__)
>   #include <asm/cputable.h>
>   #include <linux/auxvec.h>
> @@ -56,6 +61,26 @@ int ff_get_cpu_flags_ppc(void)
>       if (result == VECTORTYPE_ALTIVEC)
>           return AV_CPU_FLAG_ALTIVEC;
>       return 0;
> +#elif HAVE_GETAUXVAL || HAVE_ELF_AUX_INFO
> +    int flags = 0;
> +
> +    unsigned long hwcap = ff_getauxval(AT_HWCAP);
> +#ifdef PPC_FEATURE2_ARCH_2_07
> +    unsigned long hwcap2 = ff_getauxval(AT_HWCAP2);
> +#endif
> +
> +    if (hwcap & PPC_FEATURE_HAS_ALTIVEC)
> +       flags |= AV_CPU_FLAG_ALTIVEC;
> +#ifdef PPC_FEATURE_HAS_VSX
> +    if (hwcap & PPC_FEATURE_HAS_VSX)
> +       flags |= AV_CPU_FLAG_VSX;
> +#endif
> +#ifdef PPC_FEATURE2_ARCH_2_07
> +    if (hwcap2 & PPC_FEATURE2_ARCH_2_07)
> +       flags |= AV_CPU_FLAG_POWER8;
> +#endif
> +
> +    return flags;
>   #elif defined(__APPLE__) || defined(__NetBSD__) || defined(__OpenBSD__)
>   #if defined(__NetBSD__) || defined(__OpenBSD__)
>       int sels[2] = {CTL_MACHDEP, CPU_ALTIVEC};