[PATCH] D107330: [GlobalISel] Combine shr(shl x, c1), c2 to G_SBFX/G_UBFX

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


================
Comment at: llvm/lib/CodeGen/GlobalISel/CombinerHelper.cpp:4161
+  // Make sure that the shift sizes can fit a bitfield extract. Also we don't
+  // want to run this if ShlAmt == ShrAmt to let the G_SEXT_INREG combine handle
+  // this case.
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This will also skip the unsigned n==k case, which you probably do want to turn into ubfx?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D107330/new/

https://reviews.llvm.org/D107330