[PATCH] D36596: [InstCombine] Don't convert all dbg.declares to dbg.values

[Adrian Prantl via Phabricator via llvm-commits]

aprantl added a comment.

>   It can also be problematic if stack coloring arranges to reuse the stack memory for other data.

If lifetime intrinsics survive into MIR, then we could teach DebugValueHistoryCalculator about them. Otherwise we could have the stack coloring pass lower dbg.declares describing allocas with lifetime intrinsics into a `dbg.value(%alloca, ...)` at the beginning and a `dbg.value(null, ...)` at the end of the live range.


https://reviews.llvm.org/D36596