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Re: PATCH: [BZ #12191] 32bit memset-sse2.S fails with uneven cache size


On Thu, Nov 4, 2010 at 5:51 PM, Ulrich Drepper <drepper@gmail.com> wrote:
> On Wed, Nov 3, 2010 at 19:39, H.J. Lu <hongjiu.lu@intel.com> wrote:
>> 32bit memset-sse2.S assumes cache size is multiple of 128 bytes.
>
> Is this only a problem with then 32-bit memset? ?The code also changes
> the behavior for the 64-bit code.
>
> And what about memcpy? ?Is that code also affected? ?Or should that
> code use the raw number now? ?It can be larger.
>

SSE memory functions work on multiple of 16byte chunks. Cache size
of 1258291 byte isn't a useful threshold. .Round cache size to 256byte
shouldn't change behavior on most of processors since their cache sizes
are multiple of 256bytes. I don't expect any SSE memory functions will use
raw values. I added them just in case someone finds them useful.

-- 
H.J.


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