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Re: Use-and-clobber insns and some ancient combine.c code


    Your change added a *second* test, for substitution of

      (set (reg Y)  (...(some use of reg X)...))
    into
      (parallel [ ...(some use of reg Y)...  (clobber (reg X)) ...])

    It this *this* check I don't understand.

I think it's indeed the earlyclobber issue: you can't be sure that the
clobber will happen before X is read.


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