Add libcsse report.

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Warren Block 2014-10-09 01:44:20 +00:00
parent e1dd841bbb
commit b133015787
Notes: svn2git 2020-12-08 03:00:23 +00:00
svn path=/head/; revision=45753

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@ -1019,4 +1019,47 @@
commit bits were taken in for safe keeping.</p>
</body>
</project>
<project cat='bin'>
<title>SSE variants of libc routines for amd64</title>
<contact>
<person>
<name>
<given>John</given>
<common>Baldwin</common>
</name>
<email>jhb@FreeBSD.org</email>
</person>
</contact>
<links>
<url href="http://trac.baldwin.cx:8080/freebsd/wiki/LibCSSE" />
</links>
<body>
<p>I have written SSE/AVX-optimized versions of a few libc
routines for amd64. So far the list includes <tt>memcpy</tt>,
<tt>memset</tt>, and <tt>strlen</tt>. For each routine I have
written a simple regression test as well as performed some
simple microbenchmarks on various AMD and Intel CPUs.</p>
<p>The simplest routine is <tt>strlen</tt> which appears to be a
general win in microbenchmarks. <tt>memcpy</tt> and
<tt>memset</tt> have proven trickier as different variants can
behave quite differently on different CPUs.</p>
<p>At present, I do not yet have a patch relative to libc. Once
I do, this will be suitable for more testing. I'd like to see
some real-world benchmarks that show measurable improvement
before pushing any of this up into the tree.</p>
</body>
<help>
<task>
<p>Create a branch that holds a modified libc and is suitable
for testing</p>
</task>
</help>
</project>
</report>