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Re: [PATCH] Add i386 torture harness

On Wed, 25 Oct 2006, Uros Bizjak wrote:

> Richard Guenther wrote:
> +        { -O0 -msse -mno-sse2 -mfpmath=sse,387 } \
> +        { -O0 -msse -msse2 -mfpmath=sse,387 } \
> Is there a reason to use -mfpmath=sse,387 instead of plain
> -mfpmath=387? -mfpmath=sse,387 is considered deprecated, as the
> register allocator can't make a clear decision when FP pseudo should
> go into SSE and when into x87 register set. This usually results in
> register moves between both register sets.

Well, as long as it is a valid combination (like if you have a
processor without SSE2 but only SSE and still want to use SSE math
for floats) we should make sure we don't ICE during expansion.  Which
is the point of this torture - detect ICEs for all those weird
combinations.  But you are right that for at least x86_64 an extra
combination with -mfpmath=387 could be useful ;)

So I added

       { -O0 -mfpmath=387 } \
       { -O0 -mfpmath=387 -ffast-math } \
       { -O2 -mfpmath=387 } \
       { -O2 -mfpmath=387 -ffast-math } \

(is there a way to generate the combinations automatically with tcl?)


Richard Guenther <>
Novell / SUSE Labs

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