[PATCH] D76500: GlobalISel: Lower funnel shifts

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added inline comments.
Herald added a project: LLVM.


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Comment at: llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp:4190
+
+  Register InvShAmt = MIRBuilder.buildSub(ShTy, BitWidthC, ShAmt).getReg(0);
+  auto ShX = MIRBuilder.buildShl(Ty, X, IsFSHL ? ShAmt : InvShAmt);
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@arsenm In D80489 for SelectionDAG we changed the pow2 InvShAmt case to ~ShAmt & Mask to help targets that can only use the bottom bits of the shift amount.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D76500/new/

https://reviews.llvm.org/D76500