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Re: [PATCH][RFC][x86] Fix PR91154, add SImode smax, allow SImode add in SSE regs


On Sun, Aug 04, 2019 at 07:11:01PM +0200, Uros Bizjak wrote:
> Yes, the approach looks OK to me. It makes chain building mode
> agnostic, and the chain building can be used for
> a) DImode x86_32 (as is now), but maybe 64bit minmax operation can be added.
> b) SImode x86_32 and x86_64 (this will be mainly used for SImode
> minmax and surrounding SImode operations)
> c) DImode x86_64 (also, mainly used for DImode minmax and surrounding
> DImode operations)
> 
> > Still need help with the actual patterns for minmax and how the splitters
> > should look like.
> 
> Please look at the attached patch. Maybe we can add memory_operand as
> operand 1 and operand 2 predicate, but let's keep things simple for
> now.

Shouldn't it be used also for p{min,max}ud rather than just p{min,max}sd?
What about p{min,max}{s,u}{b,w,q}?  Some of those are already in SSE.

If the conversion of the chain fails, couldn't the STV pass split those
SImode etc. min/max patterns into code with branches, rather than turn it
into cmovs?

	Jakub


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