[LLVMdev] Problem with isMoveInstr

Chris Lattner sabre at nondot.org
Thu Jul 1 19:46:03 PDT 2004

On Thu, 1 Jul 2004, Alkis Evlogimenos wrote:
> > I've worked this around by making isMoveInstr return false when either of
> > operands is physical register, but looks like this defeats the purpose of
> > isMoveInstr. What kind of information I can further provide to help diagnose
> > the problem?
> Make sure gr7 is defined somewhere in the basic block the move belongs
> to. If you still see the crash it would be nice to see the interval for
> gr7 and the debug output of regalloc using -debug-only=regalloc.

One other important point: physical registers are only allowed to be live
inside of a basic block before register allocation occurs.  If you have a
value that lives across an MBB, it has to be a virtual register.



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