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Re: How to clean up i386 machine description?


> If I understand correctly it does by alternative, always tries to
> match and use the condition filed from insn pattern?
> So for example if I use "m,r" constraint and
> in condition I use GET_CODE(oeprands[x])!=MEM
> I will get "r" constraint?
> (just simple example :)

No, the idea is that you reject with the insn predicate combinations that
are not valid acording to the constraints, so that the passes before
reload can't recognize the invalid insns, and reload has less work.
reload itself is still constraint driven.


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