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Re: Questions about i386 redundant test and comparison removal



  In message <199806081451.KAA09834@jwlab.FEITH.COM>you write:
  > In this situation regx is a SET_DEST.  If I'm not tracking SET_DESTs
  > then why would the compiler ever think that (set (cc0) (regx)) is
  > redundant?  I'm not saying that we shouldn't track SET_DESTs, I'm just
  > trying to make sure I understand what's going on. :-)
I think we're just talking past each other.  Sorry for being
dense.

Yes, if you don't track SET_DESTs, then you can't remove a redundant
"tst" instruction.

jeff


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