[clang] [lld] [llvm] [ThinLTO] Reduce the number of renaming due to promotions (PR #178587)

[Teresa Johnson via cfe-commits]

teresajohnson wrote:

> One request: please avoid force pushing changes when possible. It makes it impossible to use github's support for comparing to my last review or other old commits. See https://llvm.org/docs/GitHub.html#rebasing-pull-requests-and-force-pushes.

Gentle reminder to avoid force pushing while review in progress.

https://github.com/llvm/llvm-project/pull/178587