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Re: Question about movM insn restrictions
On Fri, May 10, 2002 at 01:27:18PM -0400, DJ Delorie wrote:
> 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
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.