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From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Thu, 21 Oct 2021 16:10:35 -0700
Message-ID: <CAMe9rOoGVvUmS09uKzKyoEad031f-iL1qG96sRWZDW_y42gS2g@mail.gmail.com>
Subject: Re: [PATCH v8 2/3] String: Add hidden defs for __memcmpeq() to enable
 internal usage
To: Joseph Myers <joseph@codesourcery.com>
Cc: Noah Goldstein <goldstein.w.n@gmail.com>,
 GNU C Library <libc-alpha@sourceware.org>
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On Thu, Oct 21, 2021 at 4:08 PM Joseph Myers <joseph@codesourcery.com> wrote:
>
> On Thu, 21 Oct 2021, H.J. Lu via Libc-alpha wrote:
>
> > There are many memcmp calls in ld.so.   I think most, if not all, of them
> > can be changed to __memcmpeq.   Can you make another patch to do
> > that?
>
> Rather than doing that micro-optimization in the glibc sources, I think
> it's better to add the relevant feature to GCC and let glibc get optimized
> when built with a new-enough compiler.
>

Why not? We don't know when __memcmpeq will be supported by GCC
used by glibc developers.   If we don't even use it in glibc, why bother?


--
H.J.