[llvm] [CodeGen][Spill2Reg] Initial patch (PR #118832)

[via llvm-commits]

https://github.com/vporpo commented:

> There are some DFS on the CFG and do you have data about the impact to compilation speed?

It's been a while since I tested this pass, but as far as I remember it wasn't too bad. The traversals done in the code generation phase of the pass are not too frequent as they only happen when we need to spill to vector registers, which shouldn't be too often.

https://github.com/llvm/llvm-project/pull/118832