[MPlayer-dev-eng] [PATCH] Set HAVE_FAST_CLZ according to CPU type

Zuxy Meng zuxy.meng at gmail.com
Mon Jan 18 08:00:25 CET 2010


Hi,

The attached patch adds support for detecting fast CLZ.

_fast_clz is set to "yes" for alpha, avr32, mips and ppc. For ARM,
it's set only when armv5te is present. For x86, it's set for K10, all
Family 6 Intel CPUs and Willamette and Northwood P4s. Overall the
patch is in sync with ffmpeg.

Two notes however:
1) x86/x86-64 runtime detection sets _fast_clz to "yes" because I
assume that CPUs with a fast bsr/lzcnt have already enjoyed a larger
market share than those w/o one, and it's the way of the future.
2) Intel Atom isn't properly detected in this patch and will be addressed later.

-- 
Zuxy
Beauty is truth,
While truth is beauty.
PGP KeyID: E8555ED6
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