[clang] [llvm] [RegisterCoalescer] Improve register allocation for return values by limiting rematerialization (PR #163047)

[Quentin Colombet via llvm-commits]

https://github.com/qcolombet requested changes to this pull request.

I don't feel this is the right way to fix this problem.
This looks like too specific and not really a coalescing problem.

https://github.com/llvm/llvm-project/pull/163047