public inbox for libc-alpha@sourceware.org
 help / color / mirror / Atom feed
From: "H.J. Lu" <hjl.tools@gmail.com>
To: GNU C Library <libc-alpha@sourceware.org>
Subject: Re: [PATCH] x86-64: Optimize memrchr with AVX2
Date: Fri, 09 Jun 2017 11:34:00 -0000	[thread overview]
Message-ID: <CAMe9rOqECom9zD_yLhOp4ug0-8jXpitL_VdyQTvwy94j2Rhdug@mail.gmail.com> (raw)
In-Reply-To: <CAMe9rOoioz=Yxb4Hr-HBpGwgYEMkLqpCsXJ1Tbj3dC7vf1MN=A@mail.gmail.com>

On Fri, Jun 2, 2017 at 12:50 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Thu, Jun 1, 2017 at 11:13 AM, H.J. Lu <hongjiu.lu@intel.com> wrote:
>> Optimize memrchr with AVX2 to search 32 bytes with a single vector
>> compare instruction.  It is as fast as SSE2 memrchr for small data
>> sizes and up to 1X faster for large data sizes on Haswell.  Select
>> AVX2 memrchr on AVX2 machines where vzeroupper is preferred and AVX
>> unaligned load is fast.
>>
>> Any comments?
>>
>> H.J.
>> --
>>         * sysdeps/x86_64/multiarch/Makefile (sysdep_routines): Add
>>         memrchr-avx2.
>>         * sysdeps/x86_64/multiarch/ifunc-impl-list.c
>>         (__libc_ifunc_impl_list): Add tests for __memrchr_avx2 and
>>         __memrchr_sse2.
>>         * sysdeps/x86_64/multiarch/memrchr-avx2.S: New file.
>>         * sysdeps/x86_64/multiarch/memrchr.S: Likewise.
>
> Updated patch with IFUNC selector in C.
>

I will check it in.


-- 
H.J.

      reply	other threads:[~2017-06-09 11:34 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-06-01 18:13 H.J. Lu
2017-06-02 19:51 ` H.J. Lu
2017-06-09 11:34   ` H.J. Lu [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CAMe9rOqECom9zD_yLhOp4ug0-8jXpitL_VdyQTvwy94j2Rhdug@mail.gmail.com \
    --to=hjl.tools@gmail.com \
    --cc=libc-alpha@sourceware.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).