[LLVMdev] Coalescing and VNInfo

[David Greene]

On Tuesday 25 September 2007 10:49, David Greene wrote:
> I've hit a bug in a refactored version of coalescing and I'm trying to
> understand what is going on.  In particular, I'm curious about this
> line in SimpleRegisterCoalescing.cpp:
>
> 00710       LHSValsDefinedFromRHS[VNI] =
> RHS.getLiveRangeContaining(VNI->def-1)->valno;
>
> Why VNI->def-1?  The bug I'm seeing is that RHS returns a NULL
> LiveRange because it doesn't contain VNI->def-1:
>
> %reg1093,0 = [5750,5754:2)[5754,5782:1)[5782,5858:0)[5868,5870:0)
> 0 at 5782-(5858 5870) 1 at 5754-(5778) 2 at 5750

I should aff that VNI->def is 5750 which is in the interval.

                                                          -Dave