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Hm. Clear, brief, instructive. Smells a lot like a mini-HOWTO. |
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On 9/3/05, waltdnes@××××××××.org <waltdnes@××××××××.org> wrote: |
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|
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> There are CPU flags and there are USE flags. Some of them have the |
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> same names, and that may confuse you. It works like this... |
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> 1) Get a listing of your cpu's flags in /proc/cpuinfo |
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> 2) Check against the list of supported flags in gcc for you cpu, and |
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> add them to CFLAGS |
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> 3) Check http://www.gentoo.org/dyn/use-index.xml for a list of valid |
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> USE flags, and include any that show up in /proc/cpuinfo |
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> 4) Repeat step 3) with /usr/portage/profiles/use.local.desc for any |
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> programs you're emerging. There doesn't seem to be anything |
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> special on your pentium4, but my AMD64 not only has mmx and 3dnow, |
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> it also has mmxext and 3dnowext. mplayer can take advantage of |
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> them. I include them in the /etc/portage/package.use entry for |
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> media-video/mplayer. |
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> |
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> I'll assume that you're using gcc 3.3.5. In that case, the place to |
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> look for CPU flag options is... |
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> |
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> http://gcc.gnu.org/onlinedocs/gcc-3.3.5/gcc/i386-and-x86_002d64-Options.html#i386-and-x86_002d64-Options |
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> |
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> That list shows pentium4, mmx, sse, and sse2. Also, if you have *ANY* |
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> version of sse available, you can improve performance by running floating |
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> point math via sse, rather than 387 instructions. I recommend... |
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> |
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> CFLAGS="-O2 -pipe -fomit-frame-pointer -march=pentium4 -mmmx -msse -msse2 -mfpmath=sse" |
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> |
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> http://www.gentoo.org/dyn/use-index.xml shows mmx and sse as valid USE |
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> flags, so you can include them in USE. |
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> |
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> -- |
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> Walter Dnes <waltdnes@××××××××.org> |
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> My musings on technology and security at http://tech_sec.blog.ca |
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> -- |
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> gentoo-user@g.o mailing list |
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> |
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> |
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|
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-- |
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