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

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

On Fri, Jun 23, 2017 at 8:12 AM, Florian Weimer <fweimer@redhat.com> wrote:
> On 06/23/2017 05:08 PM, H.J. Lu wrote:
>> On Fri, Jun 23, 2017 at 6:51 AM, Florian Weimer <fweimer@redhat.com> wrote:
>>> I think this revised patch is an improvement because it avoids adding a
>>> branch.
>>>
>>> Thanks,
>>> Florian
>>
>> The memcmp-avx2-movbe.S part is OK.
>
> Thanks, I will commit it shortly.
>
>> For
>>
>> (check_result, do_random_tests): Write error messages to standard
>> output.
>>
>> any particular reason to replace error with printf?
>
> The error function writes to standard error, so the test harness does
> not capture it output in the .out file.

All string tests are like this.  We still got

FAIL: string/test-memcmp

[hjl@gnu-6 build-x86_64-linux]$ string/test-memcmp
string/test-memcmp: Wrong result in function __memcmp_avx2_movbe 1488148660 -168
string/test-memcmp: Wrong result in function __memcmp_avx2_movbe 1488237565 -168
string/test-memcmp: Wrong result in function __memcmp_avx2_movbe -1275218947 180
string/test-memcmp: Wrong result in function __memcmp_avx2_movbe -1275265792 180
                        simple_memcmp __memcmp_avx2_movbe
__memcmp_sse4_1__memcmp_ssse3 __memcmp_sse2
[hjl@gnu-6 build-x86_64-linux]$

If we want to change this,  it should be in a separate patch.

Thanks.

-- 
H.J.