[PATCH] D94949: [AArch64][RegAllocFast] Add findSpillBefore to TargetRegisterInfo

[Tomas Matheson via Phabricator via llvm-commits]

tmatheson added a comment.

@lenary sorry for the delay in responding to comments.

> I think the most important question to be answered about the approach is whether the backends use bundles anywhere else - if it does, this is probably too brittle and pseudo-instructions is a better approach, even though it adds duplication of loop insertion.

This is only applied to the AArch64 and ARM backends. The other uses of bundles in these backends (or in common passes used by these backends) that I'm aware of are:

- MVEVPTBlockPass
- Thumb2ITBlockPass
- ARMExpandPseudoInsts
- AArch64ExpandPseudoInsts

These are all added after register allocation, so unbundling before register allocation should not affect them.

There are other uses of bundles to prevent insertion of instructions (D79792 <https://reviews.llvm.org/D79792>) and to prevent reordering (D91048 <https://reviews.llvm.org/D91048>).


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D94949/new/

https://reviews.llvm.org/D94949