[tip:x86/core 1/1] arch/x86/um/../lib/csum-partial_64.c:98:12: error: implicit declaration of function 'load_unaligned_zeropad'

Eric Dumazet edumazet at google.com
Wed Nov 24 22:45:47 PST 2021


On Wed, Nov 24, 2021 at 10:32 PM Eric Dumazet <edumazet at google.com> wrote:

> -       }
> +       if (unlikely(odd))
> +               result = ror32(result, 8);
>         return (__force __wsum)result;

Oh well, gcc at least removes the conditional and generates a ror and a cmov

        mov    %edx,%eax
        ror    $0x8,%eax
        test   %r8,%r8
        cmove  %edx,%eax
        ret

clang keeps the cond jmp
         test   $0x1,%dil
         je     93
         rol    $0x18,%eax
93:    ret



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