[PATCH] Consider the frame base isn't moving in calculateDbgValueHistory.

[David Blaikie]

>>! In D5366#6, @friss wrote:
> Oh, and while I'm at it, we could throw a real data-flow liveness analysis in there to improve the situation even more (and stop truncating the liveness of every variable at the end of each BB). But this would be a bit more costly.

Yeah, this would be nice to have (as Eric said - just a matter of someone finding the care/time to do it). I'd assume it would possibly be powered by the register allocator rather than trying to recompute the liveness from scratch, but I don't know for sure. We've bandied about the idea now & then for a while now.

http://reviews.llvm.org/D5366