[PATCH] D99541: GlobalISel: Check for powers of 2 for inverse funnel shift lowering

[Jay Foad via Phabricator via llvm-commits]

foad added inline comments.


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Comment at: llvm/lib/CodeGen/GlobalISel/LegalizerHelper.cpp:5354
+  if (LI.getAction({RevOpcode, {Ty, ShTy}}).Action == Lower) {
+    // This only works for powers of 2, fallback to shifts if it fails.
+    LegalizerHelper::LegalizeResult Result = lowerFunnelShiftAsShifts(MI);
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No, it's the "WithInverse" lowering that might fail.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D99541/new/

https://reviews.llvm.org/D99541