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Re: Combine performance regression (was: Fix PR target/18701)


On Thu, Jan 20, 2005 at 06:36:03PM +0100, Ulrich Weigand wrote:
> (insn 226 225 227 5 (parallel [
>             (set (subreg:SI (reg:HI 78) 0)
>                 (and:SI (subreg:SI (reg:QI 79) 0)
>                     (const_int 255 [0xff])))
>             (clobber (reg:CC 33 %cc))

Alternately, the bug is the s390 port exposing the AND as the method
of zero extend too early.  You'll note that other targets such as Alpha,
powerpc, and sparc (which also have to do this via AND) do not expose
this detail ever.


r~


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