[llvm] [AMDGPU] Handle amdgpu.last.use metadata (PR #83816)

[Mirko Brkušanin via llvm-commits]

mbrkusanin wrote:

First commit is part of: https://github.com/llvm/llvm-project/pull/83814
Second and third commits are part of: https://github.com/llvm/llvm-project/pull/83815


https://github.com/llvm/llvm-project/pull/83816