Re: [PATCH] math: x86: Use prefix for FP_INIT_ROUNDMODE

["H.J. Lu" <hjl.tools@gmail.com>]

On Thu, Sep 1, 2022 at 6:03 AM Adhemerval Zanella via Libc-alpha
<libc-alpha@sourceware.org> wrote:
>
> Not all compilers support the inline asm prefix '%v' to emit the avx
> instruction if AVX is enable.  Use a prefix instead.
>
> Checked on x86_64-linux-gnu and i686-linux-gnu.
> ---
>  sysdeps/x86/fpu/sfp-machine.h | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/sysdeps/x86/fpu/sfp-machine.h b/sysdeps/x86/fpu/sfp-machine.h
> index 5892f4f5fe..006eebe257 100644
> --- a/sysdeps/x86/fpu/sfp-machine.h
> +++ b/sysdeps/x86/fpu/sfp-machine.h
> @@ -39,9 +39,15 @@ typedef unsigned int UTItype __attribute__ ((mode (TI)));
>
>  # define FP_RND_MASK           0x6000
>
> +# ifdef __AVX__
> +#  define AVX_INSN_PREFIX      "v"
> +# else
> +#  define AVX_INSN_PREFIX      ""
> +# endif
> +
>  # define FP_INIT_ROUNDMODE                                     \
>    do {                                                         \
> -    __asm__ __volatile__ ("%vstmxcsr\t%0" : "=m" (_fcw));      \
> +    __asm__ __volatile__ (AVX_INSN_PREFIX "stmxcsr\t%0" : "=m" (_fcw)); \
>    } while (0)
>  #else
>  # define _FP_W_TYPE_SIZE       32
> --
> 2.34.1
>

LGTM.

Thanks.

-- 
H.J.