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Re: Problems with FP compares / mixed SSE and I387 code


On Fri, Jan 07, 2005 at 10:34:48AM +0100, Uros Bizjak wrote:
> Some progress was achieved by separating SSE and x87 floating point 
> operators by TARGET_SSE_MATH, and it was again shown that a small 
> (ehm...) oversight in i386.md produced another big performance problem [3].
> 
> Regarding these reports, I would suggest this solution:
> - with TARGET_SSE_MATH, _all_ SFmode values should be processed in SSE 
> registers.
> - with TARGET_SSE_MATH && TARGET_SSE2, _all_ SFmode and DFmode values 
> should be processed in SSE registers.

Well, if you have __asm with "f", "t" or "u" constraints, you should still
put SFmode resp. DFmode values into the stacked registers.

	Jakub


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