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From: David Chisnall <theraven@FreeBSD.org>
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To: Roman Divacky <rdivacky@FreeBSD.org>
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Subject: Re: Compiler performance tests on FreeBSD 10.0-CURRENT
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On 6 Sep 2012, at 09:43, Roman Divacky wrote:

> Was this compiled as amd64 or i386? Also, can you send me the test =
case?
> So that we can explore the difference. The working theory now is SSE =
vs FPU
> mathematics, but it would be nice to see the testcase.

There may also be a difference in whether -ffast-math is the default on =
each compiler.  On x86, this will replace a number of libm calls with =
(much faster, but less accurate) SSE or x87 instructions.  If this is =
enabled by default with clang and not with gcc, it would account for the =
difference. =20

David=