[llvm-branch-commits] [llvm] [WIP][CodeGen][DebugInfo][RISCV] Support scalable offsets in CFI (PR #170607)

[Philip Reames via llvm-branch-commits]

https://github.com/preames commented:

I went looking for how we handle scalable offsets in the current vector frame setup and CSR handling, and found appendScalableVectorExpression and createDefCFAExpression in RISCVFrameLowering.cpp.  Looking at the diff, I just noticed that there's an NFC buried in here -- we're replacing that logic with the new CFA Op being defined.  

My overall question is Why?  Why is the existing scheme not adequate for the new purpose?

https://github.com/llvm/llvm-project/pull/170607