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Re: [tree-ssa] Copy prop into virtual operands

On Tue, 2003-07-29 at 11:07, Diego Novillo wrote:
> On Tue, 2003-07-29 at 10:56, law@redhat.com wrote:
> > This patch implements copy propagation into virtual operands.  Copy
> > propagation into virtual operands allows us to detect a number of
> > redundant loads that we were missing.
> > 
> Excellent!
> 
> > The only "tricky" parts of this patch are:
> > 
> >   1. We only propagate SSA_NAMEs in the VUSES/VDEFs.  Propagating a constant
> >      into a virtual operand seems extremely wrong to me.
> > 
> Right.  But I don't see how we would get into this situation.  After
> all, we only do constant propagation on real operands.
> 
How do you know what a real operand is now?  you don't have a flag any
more...

Andrew
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