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Re: [PATCH] fast Copysign for PPC, -flag_unsafe_math_optimizations only


On Sun, Jan 30, 2005 at 07:12:40PM -0500, Andrew Pinski wrote:
> With this patch copysign is expanded to:
>         fabs f0,f1
>         fnabs f1,f1
>         fsel f1,f2,f0,f1
> 
> Which is faster and smaller than storing and doing
> bitfield operations on the sign bit.

I would be surprised if this ever gets used, but the proper
test is HONOR_SIGNED_ZEROS, not flag_unsafe_math_optimizations.


r~


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