[Mesa-dev] [PATCH] llvmpipe: Optimize new fs state setup

[Adam Jackson]

On Thu, 2011-06-30 at 03:36 +0200, Roland Scheidegger wrote:
> Ok in fact there's a gcc bug about memcmp:
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43052
> In short gcc's memcmp builtin is totally lame and loses to glibc's
> memcmp (including call overhead, no knowledge about alignment etc.) even
> when comparing only very few bytes (and loses BIG time for lots of bytes
> to compare). Oops. Well at least if the strings are the same (I'd guess
> if the first byte is different it's hard to beat the gcc builtin...).
> So this is really a gcc bug. The bug is quite old though with no fix in
> sight apparently so might need to think about some workaround (but just
> not doing the comparison doesn't look like the right idea, since
> apparently it would be faster with the comparison if gcc's memcmp got
> fixed).

How do things fare if you build with -fno-builtin-memcmp?

- ajax
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