[InstCombine] Make MatchBSwap also match bit reversals

MatchBSwap has most of the functionality to match bit reversals already. If we switch it from looking at bytes to individual bits and remove a few early exits, we can extend the main recursive function to match any sequence of ORs, ANDs and shifts that assemble a value from different parts of another, base value. Once we have this bit->bit mapping, we can very simply detect if it is appropriate for a bswap or bitreverse.

llvm-svn: 255334

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineInternal.h b/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
index 1bb3ad6c534..534f6700815 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
+++ b/llvm/lib/Transforms/InstCombine/InstCombineInternal.h
@@ -556,7 +556,7 @@ private:
   Value *InsertRangeTest(Value *V, Constant *Lo, Constant *Hi, bool isSigned,
                          bool Inside);
   Instruction *PromoteCastOfAllocation(BitCastInst &CI, AllocaInst &AI);
-  Instruction *MatchBSwap(BinaryOperator &I);
+  Instruction *MatchBSwapOrBitReverse(BinaryOperator &I);
   bool SimplifyStoreAtEndOfBlock(StoreInst &SI);
   Instruction *SimplifyMemTransfer(MemIntrinsic *MI);
   Instruction *SimplifyMemSet(MemSetInst *MI);