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From: Denys Vlasenko <vda.linux@googlemail.com>
Newsgroups: gmane.linux.lib.musl.general
Subject: Re: [PATCH 1/2] x86_64/memset: simple optimizations
Date: Tue, 10 Feb 2015 22:08:29 +0100
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On Tue, Feb 10, 2015 at 9:50 PM, Rich Felker <dalias@libc.org> wrote:
> On Tue, Feb 10, 2015 at 06:30:56PM +0100, Denys Vlasenko wrote:
>> "and $0xff,%esi" is a six-byte insn (81 e6 ff 00 00 00), can use
>> 4-byte "movzbl %sil,%esi" (40 0f b6 f6) instead.
>> [...]
>
> Do you want to go ahead with these patches as-is, or consider some of
> the other ideas we discussed off-list like avoiding the 64-bit imul
> entirely in the small-n case? If you think that's easy as another
> incremental change I'll go ahead with these

I think you can apply these patches without waiting
for potential future improvements.