[PATCH] D110488: [InstCombine] Canonicalize ((X & -X) - 1) --> (~X & (X - 1)) (PR51784)

[Sanjay Patel via Phabricator via llvm-commits]

spatel added inline comments.


================
Comment at: llvm/test/Transforms/InstCombine/add-mask-neg.ll:29
   %neg = sub i32 0, %X
   %mask = and i32 %X, %neg
   %dec = add i32 %mask, -1
----------------
This test gets canonicalized by complexity, so it's not testing the pattern that was intended. Needs another instruction to thwart that transform.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D110488/new/

https://reviews.llvm.org/D110488