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Re: [PATCH 18/n, 386]: Fix PR85694, Generation of vectorized AVG (Average) instruction
- From: Uros Bizjak <ubizjak at gmail dot com>
- To: "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>
- Cc: Richard Sandiford <richard dot sandiford at arm dot com>
- Date: Wed, 4 Jul 2018 10:26:12 +0200
- Subject: Re: [PATCH 18/n, 386]: Fix PR85694, Generation of vectorized AVG (Average) instruction
- References: <CAFULd4bTNaU5KZi1VC3kc94tM69XyR=nxZJoq0dPUyWz+r81FQ@mail.gmail.com>
On Tue, Jul 3, 2018 at 7:38 PM, Uros Bizjak <email@example.com> wrote:
> 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 ). Results with
CFLAGS="-Ofast -mavx2" show that:
$ objdump -d ldecod.exe | grep pavg | wc -l
$ objdump -d lencod.exe | grep pavg | wc -l
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  to
pick up the patch.