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Re: [patches] Re: SSE min/max instruction support


On Sat, Feb 24, 2001 at 11:40:44PM +0100, Jan Hubicka wrote:
> Note that the definition if min/max for floats is pretty touchy.
> SSE defines that for two zeros, always second zero is returned
> and for unordered too, so it corresponds to the <
> other may define <= equivalent or some other changes.

Investigating, it seems that we only ever create smin/smax
for floats if fast_math.

> Perhaps keeping if_then_else is better way and update the
> ia64/rs6000 respectivly.

I guess that is probably best.

I think you do want to go ahead and have the "minsf3" etc expanders
though, so that the middle-end can go ahead and create the patterns
directly when it needs to.

It would also be good to teach ifcvt how to use the min/max
expanders.  A couple of targets have special code sequences
or explicit min/max insns.


r~


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