d20a1b87f6
According to https://llvm.org/docs/HowToUpdateDebugInfo.html#when-to-preserve-an-instruction-location, when moving (and in our case cloning) within the same BB, the debug location is preserved. But when moving / cloning to a different BB, we preserve the debug location only if the destination BB contains the same location. Currently we preserve the debug loc unconditionally in all cases. This CL correctly handles the debug locs in DebugValueManager. Reviewed By: dschuff Differential Revision: https://reviews.llvm.org/D148115