[PATCH] implement rint{,f,l}, floor{,f,l}. ceil{,f,l}, trunc{,f,l} and nearbyint{,f,l} as x87 built-in functions

Richard Henderson rth@redhat.com
Wed Aug 25 19:16:00 GMT 2004


On Wed, Aug 25, 2004 at 07:56:57AM -0600, Roger Sayle wrote:
> Ideally the OPTIMIZE_MODE_SWITCHING would be used to control
> the placement of the "fldcw" instructions that actually change
> the mode.

You cannot do this until you figure out how to get the x86 backend to
spill fp-stack registers in XFmode.  Otherwise the round+store operation
will be done with a non-standard rounding mode.

Of course, spilling in XFmode is a good idea for other reasons as well.


r~



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