On Fri, Dec 6, 2013 at 9:42 AM, Richard Sandiford <rdsandif...@googlemail.com> wrote: > Eric Botcazou <ebotca...@adacore.com> writes: >>> Well, I think making the simplify-rtx code conditional on the target >>> would be the wrong way to go. If we really can't live with it being >>> unconditional then I think we should revert it. But like I say I think >>> it would be better to make combine recognise the redundancy even with >>> the new form. (Or as I say, longer term, not to rely on combine to >>> eliminate redundant extensions.) But I don't have time to do that myself... >> >> It helps x86 so we won't revert it. My fear is that we'll need to add code >> in >> other places to RISCify back the result of this "simplification". > > Sorry, realised I didn't respond to this yesterday. I wasn't suggesting > we just revert and walk away. ISTR the original suggestion was to patch > combine instead of simplify-rtx.c, so we could back to that.
I think that looks most sensible. Richard. > Thanks, > Richard
