[PATCH] x86-64: memcmp-avx2-movbe.S needs saturating subtraction [BZ #21662]

[Richard Henderson]

On 06/23/2017 06:51 AM, Florian Weimer wrote:
> +	shll	$8, %eax
> +	shll	$8, %ecx
>   	bswap	%eax
>   	bswap	%ecx
> +	movzbl	-1(%rdi, %rdx), %edi
> +	movzbl	-1(%rsi, %rdx), %esi
> +	orl	%edi, %eax
> +	orl	%esi, %ecx

Do you really need to re-load and merge the final byte?
It would appear you could leave the low byte zero.


r~