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Re: Question about movM insn restrictions



> > Use a define_expand for movM and have it expand into the appropriate
> > specific pattern(s).  Once it's expanded by name, you can use as few
> > or as many patterns as you like, as long as they're unambiguously
> > matchable.
> 
> No!  Absolutely not!
> 
> Each insn pattern is reloaded individually.  Therefore if you split
> the alternatives across different patterns, you prevent the register
> allocator from doing its job.  And can in fact result in reload aborts.

Gak, this sounds bad.  I don't recall seeing *that* documented.


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