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Re: [PATCH 18/n, 386]: Fix PR85694, Generation of vectorized AVG (Average) instruction


On Tue, Jul 3, 2018 at 7:38 PM, Uros Bizjak <ubizjak@gmail.com> wrote:
> Hello!
>
> Attached patch implements unsigned HImode and QImode vector average
> instructions. This is all x86 has to offer...

FYI, I have tried the effectiveness of patched gcc with SPEC CPU2006
464.h264 (actually, jm19.0.zip source from [1]). Results with
CFLAGS="-Ofast -mavx2" show that:

$ objdump -d ldecod.exe | grep pavg | wc -l
6
$ objdump -d lencod.exe | grep pavg | wc -l
24

while without your patch, there were no instances of pavg found.

Quite impressive effect!

BTW: I didn't check the runtime, I'll wait for gcc SPEC tester [2] to
pick up the patch.

Uros.

[1] http://iphome.hhi.de/suehring/tml/download/
[2] https://vmakarov.fedorapeople.org/spec/index.html


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