Re: [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
2021-11-25T06:48:03Z

On Wed, Nov 24, 2021 at 10:32 PM Eric Dumazet <edumazet@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