[LLVMdev] A question about instruction operands.

[sanjiv gupta]

On Tue, 2008-09-23 at 13:33 +0100, Richard Osborne wrote:
> sanjiv gupta wrote:
> > I have a question:
> > In the pattern below from X86
> >
> > def INC8r  : I<0xFE, MRM0r, (outs GR8 :$dst), (ins GR8 :$src),
> > 			"inc{b}\tdst",
> > 		  [(set GR8:$dst, (add GR8:$src, 1))]>;
> >
> > Since we are emitting only "inc $dst",
> > What makes sure that the $src and $dst are same register?
> >
> > - Sanjiv
> It's enclosed inside :
> 
> let isTwoAddress = 1 in {
> ...
> }
> 
> (you'll need to scroll up a fair amount to find this).
> 
That means, it gets converted to
dst = src;
dst = dst + 1;

Right ?

- Sanjiv

> Richard
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