[PATCH] D99283: [GlobalISel] Combine and (lshr x, cst), mask -> ubfx x, cst, width

[Jessica Paquette via Phabricator via llvm-commits]

paquette updated this revision to Diff 346771.
paquette added a comment.

- Fix UB by doing all the computations on unsigned ints (which is what SDAG does anyway)
- Simplify the logic a little bit more
- Add boundary testcases which use signed + unsigned max integer values

(Maybe there should be a `m_UICst(...)` matcher or something...?)


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D99283/new/

https://reviews.llvm.org/D99283

Files:
  llvm/lib/Target/AArch64/AArch64Combine.td
  llvm/lib/Target/AArch64/GISel/AArch64PostLegalizerCombiner.cpp
  llvm/test/CodeGen/AArch64/GlobalISel/form-bitfield-extract-from-and.mir

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