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Re: birthpoints in rtl.


> Diego,
> 
> I am leaning to just adding noop moves at the birthpoints (dominance
> frontiers) as real noop move insns in the streams in the passes that use
> ud or du chains.   The back end is tolerant of noop moves and without

Hi,
while I am with Diego that would preffer PHI nodes on side especially in
FUD chain where rest of your SSA is on side too.  But if we go with the
extra instruction scheme, I think you are much better to use RTL USE
instruction.  The moves are generated by target machinery and can do
funny things, like clobbering flags or whatever.  USEs are transparent
this way.

Honza


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