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Re: Problems with FP compares / mixed SSE and I387 code
Jakub Jelinek wrote:
On Fri, Jan 07, 2005 at 10:34:48AM +0100, Uros Bizjak wrote:I was trying to say that all allocated SFmode (and DFmode for SSE2)
registers should be SSE registers. Only one move from SSE to x87 for
final return value would be needed in this case.
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 .
Regarding these reports, I would suggest this solution:
- with TARGET_SSE_MATH, _all_ SFmode values should be processed in SSE
- 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.