Assembly string functions in i386 libc

Matthew Dillon dillon at apollo.backplane.com
Wed Jul 11 23:51:23 UTC 2007


:Since strlen() is used in every program directly or indirectly through
:libc, I thought it was beneficial to make it faster.  In the case of
:i386, the C version used by all the other architectures, except for ARM,
:is much faster that the assembly version.  This is without any
:optimization on its part.
:
:I need to test out grep (FreeGrep) to see how it behaves when calling
:regexec() (may use strlen() in certain cases) many times (i.e., grep -R
:on the source tree) using both versions.
:
:Sean
:-- 
:scf at FreeBSD.org

    Yes, but there's a difference between using strlen() a couple of 
    times in the program and using it in a core processing loop or
    other high-performance element of the program.  And even if it is
    used in such places it isn't going to be used so often that the
    program would actually benefit from the few nanoseconds of improvement
    you might get from it.  The chances of that are nearly zero. 

						-Matt


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