[llvm] [VectorCombine] Add special handling for truncating shuffles (PR #70013)

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git-clang-format --diff ba468d4dab4e528532b57144e564b2fc782035fe ae8360674dcfba05a5391bb9cf7be8a408fcf200 -- llvm/lib/Transforms/Vectorize/VectorCombine.cpp
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View the diff from clang-format here.
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diff --git a/llvm/lib/Transforms/Vectorize/VectorCombine.cpp b/llvm/lib/Transforms/Vectorize/VectorCombine.cpp
index 943ff52bf..0cfbd0f06 100644
--- a/llvm/lib/Transforms/Vectorize/VectorCombine.cpp
+++ b/llvm/lib/Transforms/Vectorize/VectorCombine.cpp
@@ -1484,13 +1484,15 @@ bool VectorCombine::foldShuffleFromReductions(Instruction &I) {
   // This requires special handling.
   bool IsTruncatingShuffle = VecType->getNumElements() < NumInputElts;
   bool UsesSecondVec =
-      any_of(ConcatMask, [&](int M) { return M >= (int) NumInputElts; });
+      any_of(ConcatMask, [&](int M) { return M >= (int)NumInputElts; });
   InstructionCost OldCost = TTI.getShuffleCost(
       UsesSecondVec ? TTI::SK_PermuteTwoSrc : TTI::SK_PermuteSingleSrc,
-      (UsesSecondVec && !IsTruncatingShuffle) ? VecType : ShuffleInputType, Shuffle->getShuffleMask());
+      (UsesSecondVec && !IsTruncatingShuffle) ? VecType : ShuffleInputType,
+      Shuffle->getShuffleMask());
   InstructionCost NewCost = TTI.getShuffleCost(
       UsesSecondVec ? TTI::SK_PermuteTwoSrc : TTI::SK_PermuteSingleSrc,
-      (UsesSecondVec && !IsTruncatingShuffle) ? VecType : ShuffleInputType, ConcatMask);
+      (UsesSecondVec && !IsTruncatingShuffle) ? VecType : ShuffleInputType,
+      ConcatMask);
 
   LLVM_DEBUG(dbgs() << "Found a reduction feeding from a shuffle: " << *Shuffle
                     << "\n");

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https://github.com/llvm/llvm-project/pull/70013