movstrictqi/movstricthi fix for h8300

Mark Mitchell
Tue Sep 12 07:19:00 GMT 2000

>>>>> "Bernd" == Bernd Schmidt <> writes:

    Bernd> I think it would be cleaner to represent a movstrict
    Bernd> pattern as something like

    Bernd>   (set (reg X) (ior (and X 0xFF....00) (zero_extend Y)))

    Bernd> This might even help the combiner, who knows.

    Bernd> Thoughts?

I couldn't agree more, both with the overall sentiment you express,
and also with this particular case.  If you can figure out how to get
rid of this, go for it.  If that causes slightly worse code
generation, so be it: the win will still be worth it in the long run.
It should be relatively simple to show the insn recognizers how to
take the pattern you show above and do the right thing.

Mark Mitchell         
CodeSourcery, LLC     

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