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On Thursday 06 July 2006 22:02, Curtis Napier wrote: |
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> Every developer who has ever commented on one of these threads has |
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> always agreed with that. Put it in USE not CLFAGS. |
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Well it's not totally right. |
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Putting them in CFLAGS, when using -march, is redundant, pure and simple. |
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-march=athlon64 -msse -msse2 -mmmx -m3dnow -m3dnowex |
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would be equivalent of |
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-march=athlon64 |
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If you have a new Athlon64 that supports SSE3, using |
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-march=athlon64 -msse3 |
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is not only legit, but also (in my opinion at least) suggested. GCC can |
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improve heavily if it knows what it has to do. |
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The problem is that people think that using |
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-march=pentium3 -mmmx |
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will bring them more acceleration, while this isn't true. |
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So I would suggest anybody wanting to comment on these issue to know the |
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difference of using mmx in useflag and -mmmx in CFLAGS at the moment. |
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And then evaluate the change in behaviour. |
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Note: -march=i586 -mmmx for Pentium (classic) MMX is a good idea most of the |
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times, as it's not an i686 but at the same time it has MMX support. |
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-- |
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Diego "Flameeyes" Pettenò - http://farragut.flameeyes.is-a-geek.org/ |
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Gentoo/Alt lead, Gentoo/FreeBSD, Video, AMD64, Sound, PAM, KDE |
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