[PATCH] D47980: [InstCombine] Fold (x << y) >> y -> x & (-1 >> y)

[Roman Lebedev via Phabricator via llvm-commits]

lebedev.ri added subscribers: craig.topper, spatel.
lebedev.ri added a comment.

Thanks!
Do note that there does not seem to be any folds for when the offset is not 0.
E.g. (x >> start)  & (-1 >> (width - y)) might be foldable to (UBFE
$x, $start, $width)


Repository:
  rL LLVM

https://reviews.llvm.org/D47980