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Re: RTL sharing tester (for testing)

Richard Sandiford wrote: 
If every register in [regno_first, regno_last] was unused, flow would
add a REG_UNUSED note for the REG created above.  If only some of those
registers were unused, flow would add notes for the individual unused
registers.  As I said on IRC yesterday, I'm not convinced the first
behaviour was a good idea.  That REG might well be invalid (otherwise
why have a SUBREG in the first place?) and it's better not to have
invalid registers floating around.

I agree with everything in your analysis, except possibly this. If the SUBREG is valid, then I see no way how the REG could be invalid. Since flow used to do this, I prefer we keep the same behaviour.


Bernd
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