On 12/3/2010 1:44 PM, Gary DiPillo wrote:
Inelegant, but how about (worst case):
LAY Rx,Target
LAY Ry,Source
MVC 0(L'Source,Rx),0(Ry)
Worst case indeed. The AGI on a code fragment like this is terrible (though I
suspect LAY has the same pipeline bypass that LA has). I suppose the compiler
would attempt to insert additional unrelated instructions after the LAYs and
before the MVC to avoid the AGI. But, even then, LAYs do not run for free. Ugh.
--
Edward E Jaffe
Phoenix Software International, Inc
831 Parkview Drive North
El Segundo, CA 90245
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[email protected]
http://www.phoenixsoftware.com/
