[LLVMdev] Live Intervals Question

Evan Cheng evan.cheng at apple.com
Tue Jun 26 22:00:27 PDT 2007


On Jun 26, 2007, at 7:08 PM, Evan Cheng wrote:

>
> CALL %RAX<imp-def>, %EAX<imp-def>...
> reg1026 = MOV32rr %EAX<kill>
> %EAX = MOV32rr %reg1027<kill>, %RAX<imp-use,kill>,%RAX<imp-def>
>
> Ok, live variables is being overly conservative here. Nothing between
> CALL and the second MOV32rr read RAX so there is no reason to extend
> the live range beyond the first move. Bugzilla please. :-)

What was I smoking? :-) RAX isn't modified by the first MOV32rr. It's  
then r/m/w by the second MOV32rr. So it's perfectly correct for its  
live range to start at CALL and extend past both MOV32rr's. No  
bugzilla please. :-)

Evan



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