[PATCH] Don't write beyond destination in __mempcpy_avx512_no_vzeroupper (bug 23196)

[Florian Weimer]

On 05/22/2018 03:21 PM, Andreas Schwab wrote:
> On Mai 22 2018, Florian Weimer <fweimer@redhat.com> wrote:
> 
>> It has to do with copy sizes and relation to the cache size.  I had to
>> adjust your reproducer to make it fail on KNL, basically increasing the
>> copy size by a factor of 10.
> 
> What is the architectural maximum cache size?

My test machine had an L2 cache size of 1 MiB.  I think the cut-over 
happens at half of that (at least for our backported version), which is why

#define N 976999

in your reproducer word for me (along with -O0 -fno-builtin).
Thanks,
Florian