679 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			679 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===--- Scalarizer.cpp - Scalarize vector operations ---------------------===//
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is distributed under the University of Illinois Open Source
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| // License. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| //
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| // This pass converts vector operations into scalar operations, in order
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| // to expose optimization opportunities on the individual scalar operations.
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| // It is mainly intended for targets that do not have vector units, but it
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| // may also be useful for revectorizing code to different vector widths.
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #include "llvm/ADT/STLExtras.h"
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| #include "llvm/IR/IRBuilder.h"
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| #include "llvm/IR/InstVisitor.h"
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| #include "llvm/Pass.h"
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| #include "llvm/Support/CommandLine.h"
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| #include "llvm/Transforms/Scalar.h"
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| #include "llvm/Transforms/Utils/BasicBlockUtils.h"
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| 
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| using namespace llvm;
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| 
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| #define DEBUG_TYPE "scalarizer"
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| 
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| namespace {
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| // Used to store the scattered form of a vector.
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| typedef SmallVector<Value *, 8> ValueVector;
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| 
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| // Used to map a vector Value to its scattered form.  We use std::map
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| // because we want iterators to persist across insertion and because the
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| // values are relatively large.
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| typedef std::map<Value *, ValueVector> ScatterMap;
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| 
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| // Lists Instructions that have been replaced with scalar implementations,
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| // along with a pointer to their scattered forms.
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| typedef SmallVector<std::pair<Instruction *, ValueVector *>, 16> GatherList;
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| 
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| // Provides a very limited vector-like interface for lazily accessing one
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| // component of a scattered vector or vector pointer.
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| class Scatterer {
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| public:
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|   Scatterer() {}
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| 
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|   // Scatter V into Size components.  If new instructions are needed,
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|   // insert them before BBI in BB.  If Cache is nonnull, use it to cache
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|   // the results.
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|   Scatterer(BasicBlock *bb, BasicBlock::iterator bbi, Value *v,
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|             ValueVector *cachePtr = nullptr);
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| 
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|   // Return component I, creating a new Value for it if necessary.
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|   Value *operator[](unsigned I);
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| 
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|   // Return the number of components.
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|   unsigned size() const { return Size; }
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| 
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| private:
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|   BasicBlock *BB;
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|   BasicBlock::iterator BBI;
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|   Value *V;
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|   ValueVector *CachePtr;
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|   PointerType *PtrTy;
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|   ValueVector Tmp;
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|   unsigned Size;
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| };
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| 
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| // FCmpSpliiter(FCI)(Builder, X, Y, Name) uses Builder to create an FCmp
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| // called Name that compares X and Y in the same way as FCI.
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| struct FCmpSplitter {
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|   FCmpSplitter(FCmpInst &fci) : FCI(fci) {}
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|   Value *operator()(IRBuilder<> &Builder, Value *Op0, Value *Op1,
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|                     const Twine &Name) const {
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|     return Builder.CreateFCmp(FCI.getPredicate(), Op0, Op1, Name);
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|   }
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|   FCmpInst &FCI;
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| };
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| 
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| // ICmpSpliiter(ICI)(Builder, X, Y, Name) uses Builder to create an ICmp
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| // called Name that compares X and Y in the same way as ICI.
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| struct ICmpSplitter {
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|   ICmpSplitter(ICmpInst &ici) : ICI(ici) {}
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|   Value *operator()(IRBuilder<> &Builder, Value *Op0, Value *Op1,
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|                     const Twine &Name) const {
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|     return Builder.CreateICmp(ICI.getPredicate(), Op0, Op1, Name);
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|   }
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|   ICmpInst &ICI;
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| };
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| 
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| // BinarySpliiter(BO)(Builder, X, Y, Name) uses Builder to create
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| // a binary operator like BO called Name with operands X and Y.
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| struct BinarySplitter {
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|   BinarySplitter(BinaryOperator &bo) : BO(bo) {}
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|   Value *operator()(IRBuilder<> &Builder, Value *Op0, Value *Op1,
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|                     const Twine &Name) const {
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|     return Builder.CreateBinOp(BO.getOpcode(), Op0, Op1, Name);
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|   }
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|   BinaryOperator &BO;
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| };
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| 
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| // Information about a load or store that we're scalarizing.
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| struct VectorLayout {
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|   VectorLayout() : VecTy(nullptr), ElemTy(nullptr), VecAlign(0), ElemSize(0) {}
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| 
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|   // Return the alignment of element I.
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|   uint64_t getElemAlign(unsigned I) {
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|     return MinAlign(VecAlign, I * ElemSize);
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|   }
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| 
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|   // The type of the vector.
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|   VectorType *VecTy;
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| 
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|   // The type of each element.
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|   Type *ElemTy;
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| 
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|   // The alignment of the vector.
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|   uint64_t VecAlign;
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| 
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|   // The size of each element.
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|   uint64_t ElemSize;
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| };
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| 
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| class Scalarizer : public FunctionPass,
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|                    public InstVisitor<Scalarizer, bool> {
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| public:
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|   static char ID;
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| 
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|   Scalarizer() :
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|     FunctionPass(ID) {
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|     initializeScalarizerPass(*PassRegistry::getPassRegistry());
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|   }
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| 
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|   bool doInitialization(Module &M) override;
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|   bool runOnFunction(Function &F) override;
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| 
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|   // InstVisitor methods.  They return true if the instruction was scalarized,
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|   // false if nothing changed.
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|   bool visitInstruction(Instruction &) { return false; }
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|   bool visitSelectInst(SelectInst &SI);
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|   bool visitICmpInst(ICmpInst &);
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|   bool visitFCmpInst(FCmpInst &);
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|   bool visitBinaryOperator(BinaryOperator &);
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|   bool visitGetElementPtrInst(GetElementPtrInst &);
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|   bool visitCastInst(CastInst &);
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|   bool visitBitCastInst(BitCastInst &);
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|   bool visitShuffleVectorInst(ShuffleVectorInst &);
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|   bool visitPHINode(PHINode &);
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|   bool visitLoadInst(LoadInst &);
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|   bool visitStoreInst(StoreInst &);
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| 
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|   static void registerOptions() {
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|     // This is disabled by default because having separate loads and stores
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|     // makes it more likely that the -combiner-alias-analysis limits will be
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|     // reached.
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|     OptionRegistry::registerOption<bool, Scalarizer,
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|                                  &Scalarizer::ScalarizeLoadStore>(
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|         "scalarize-load-store",
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|         "Allow the scalarizer pass to scalarize loads and store", false);
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|   }
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| 
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| private:
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|   Scatterer scatter(Instruction *, Value *);
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|   void gather(Instruction *, const ValueVector &);
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|   bool canTransferMetadata(unsigned Kind);
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|   void transferMetadata(Instruction *, const ValueVector &);
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|   bool getVectorLayout(Type *, unsigned, VectorLayout &, const DataLayout &);
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|   bool finish();
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| 
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|   template<typename T> bool splitBinary(Instruction &, const T &);
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| 
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|   ScatterMap Scattered;
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|   GatherList Gathered;
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|   unsigned ParallelLoopAccessMDKind;
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|   bool ScalarizeLoadStore;
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| };
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| 
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| char Scalarizer::ID = 0;
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| } // end anonymous namespace
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| 
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| INITIALIZE_PASS_WITH_OPTIONS(Scalarizer, "scalarizer",
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|                              "Scalarize vector operations", false, false)
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| 
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| Scatterer::Scatterer(BasicBlock *bb, BasicBlock::iterator bbi, Value *v,
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|                      ValueVector *cachePtr)
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|   : BB(bb), BBI(bbi), V(v), CachePtr(cachePtr) {
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|   Type *Ty = V->getType();
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|   PtrTy = dyn_cast<PointerType>(Ty);
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|   if (PtrTy)
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|     Ty = PtrTy->getElementType();
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|   Size = Ty->getVectorNumElements();
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|   if (!CachePtr)
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|     Tmp.resize(Size, nullptr);
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|   else if (CachePtr->empty())
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|     CachePtr->resize(Size, nullptr);
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|   else
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|     assert(Size == CachePtr->size() && "Inconsistent vector sizes");
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| }
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| 
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| // Return component I, creating a new Value for it if necessary.
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| Value *Scatterer::operator[](unsigned I) {
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|   ValueVector &CV = (CachePtr ? *CachePtr : Tmp);
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|   // Try to reuse a previous value.
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|   if (CV[I])
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|     return CV[I];
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|   IRBuilder<> Builder(BB, BBI);
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|   if (PtrTy) {
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|     if (!CV[0]) {
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|       Type *Ty =
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|         PointerType::get(PtrTy->getElementType()->getVectorElementType(),
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|                          PtrTy->getAddressSpace());
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|       CV[0] = Builder.CreateBitCast(V, Ty, V->getName() + ".i0");
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|     }
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|     if (I != 0)
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|       CV[I] = Builder.CreateConstGEP1_32(nullptr, CV[0], I,
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|                                          V->getName() + ".i" + Twine(I));
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|   } else {
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|     // Search through a chain of InsertElementInsts looking for element I.
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|     // Record other elements in the cache.  The new V is still suitable
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|     // for all uncached indices.
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|     for (;;) {
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|       InsertElementInst *Insert = dyn_cast<InsertElementInst>(V);
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|       if (!Insert)
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|         break;
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|       ConstantInt *Idx = dyn_cast<ConstantInt>(Insert->getOperand(2));
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|       if (!Idx)
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|         break;
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|       unsigned J = Idx->getZExtValue();
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|       V = Insert->getOperand(0);
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|       if (I == J) {
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|         CV[J] = Insert->getOperand(1);
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|         return CV[J];
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|       } else if (!CV[J]) {
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|         // Only cache the first entry we find for each index we're not actively
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|         // searching for. This prevents us from going too far up the chain and
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|         // caching incorrect entries.
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|         CV[J] = Insert->getOperand(1);
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|       }
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|     }
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|     CV[I] = Builder.CreateExtractElement(V, Builder.getInt32(I),
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|                                          V->getName() + ".i" + Twine(I));
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|   }
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|   return CV[I];
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| }
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| 
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| bool Scalarizer::doInitialization(Module &M) {
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|   ParallelLoopAccessMDKind =
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|       M.getContext().getMDKindID("llvm.mem.parallel_loop_access");
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|   ScalarizeLoadStore =
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|       M.getContext().getOption<bool, Scalarizer, &Scalarizer::ScalarizeLoadStore>();
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|   return false;
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| }
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| 
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| bool Scalarizer::runOnFunction(Function &F) {
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|   assert(Gathered.empty() && Scattered.empty());
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|   for (BasicBlock &BB : F) {
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|     for (BasicBlock::iterator II = BB.begin(), IE = BB.end(); II != IE;) {
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|       Instruction *I = &*II;
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|       bool Done = visit(I);
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|       ++II;
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|       if (Done && I->getType()->isVoidTy())
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|         I->eraseFromParent();
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|     }
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|   }
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|   return finish();
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| }
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| 
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| // Return a scattered form of V that can be accessed by Point.  V must be a
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| // vector or a pointer to a vector.
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| Scatterer Scalarizer::scatter(Instruction *Point, Value *V) {
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|   if (Argument *VArg = dyn_cast<Argument>(V)) {
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|     // Put the scattered form of arguments in the entry block,
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|     // so that it can be used everywhere.
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|     Function *F = VArg->getParent();
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|     BasicBlock *BB = &F->getEntryBlock();
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|     return Scatterer(BB, BB->begin(), V, &Scattered[V]);
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|   }
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|   if (Instruction *VOp = dyn_cast<Instruction>(V)) {
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|     // Put the scattered form of an instruction directly after the
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|     // instruction.
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|     BasicBlock *BB = VOp->getParent();
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|     return Scatterer(BB, std::next(BasicBlock::iterator(VOp)),
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|                      V, &Scattered[V]);
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|   }
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|   // In the fallback case, just put the scattered before Point and
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|   // keep the result local to Point.
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|   return Scatterer(Point->getParent(), Point->getIterator(), V);
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| }
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| 
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| // Replace Op with the gathered form of the components in CV.  Defer the
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| // deletion of Op and creation of the gathered form to the end of the pass,
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| // so that we can avoid creating the gathered form if all uses of Op are
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| // replaced with uses of CV.
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| void Scalarizer::gather(Instruction *Op, const ValueVector &CV) {
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|   // Since we're not deleting Op yet, stub out its operands, so that it
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|   // doesn't make anything live unnecessarily.
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|   for (unsigned I = 0, E = Op->getNumOperands(); I != E; ++I)
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|     Op->setOperand(I, UndefValue::get(Op->getOperand(I)->getType()));
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| 
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|   transferMetadata(Op, CV);
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| 
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|   // If we already have a scattered form of Op (created from ExtractElements
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|   // of Op itself), replace them with the new form.
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|   ValueVector &SV = Scattered[Op];
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|   if (!SV.empty()) {
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|     for (unsigned I = 0, E = SV.size(); I != E; ++I) {
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|       Instruction *Old = cast<Instruction>(SV[I]);
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|       CV[I]->takeName(Old);
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|       Old->replaceAllUsesWith(CV[I]);
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|       Old->eraseFromParent();
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|     }
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|   }
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|   SV = CV;
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|   Gathered.push_back(GatherList::value_type(Op, &SV));
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| }
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| 
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| // Return true if it is safe to transfer the given metadata tag from
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| // vector to scalar instructions.
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| bool Scalarizer::canTransferMetadata(unsigned Tag) {
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|   return (Tag == LLVMContext::MD_tbaa
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|           || Tag == LLVMContext::MD_fpmath
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|           || Tag == LLVMContext::MD_tbaa_struct
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|           || Tag == LLVMContext::MD_invariant_load
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|           || Tag == LLVMContext::MD_alias_scope
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|           || Tag == LLVMContext::MD_noalias
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|           || Tag == ParallelLoopAccessMDKind);
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| }
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| 
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| // Transfer metadata from Op to the instructions in CV if it is known
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| // to be safe to do so.
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| void Scalarizer::transferMetadata(Instruction *Op, const ValueVector &CV) {
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|   SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
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|   Op->getAllMetadataOtherThanDebugLoc(MDs);
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|   for (unsigned I = 0, E = CV.size(); I != E; ++I) {
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|     if (Instruction *New = dyn_cast<Instruction>(CV[I])) {
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|       for (SmallVectorImpl<std::pair<unsigned, MDNode *>>::iterator
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|                MI = MDs.begin(),
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|                ME = MDs.end();
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|            MI != ME; ++MI)
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|         if (canTransferMetadata(MI->first))
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|           New->setMetadata(MI->first, MI->second);
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|       New->setDebugLoc(Op->getDebugLoc());
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|     }
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|   }
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| }
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| 
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| // Try to fill in Layout from Ty, returning true on success.  Alignment is
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| // the alignment of the vector, or 0 if the ABI default should be used.
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| bool Scalarizer::getVectorLayout(Type *Ty, unsigned Alignment,
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|                                  VectorLayout &Layout, const DataLayout &DL) {
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|   // Make sure we're dealing with a vector.
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|   Layout.VecTy = dyn_cast<VectorType>(Ty);
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|   if (!Layout.VecTy)
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|     return false;
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| 
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|   // Check that we're dealing with full-byte elements.
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|   Layout.ElemTy = Layout.VecTy->getElementType();
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|   if (DL.getTypeSizeInBits(Layout.ElemTy) !=
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|       DL.getTypeStoreSizeInBits(Layout.ElemTy))
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|     return false;
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| 
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|   if (Alignment)
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|     Layout.VecAlign = Alignment;
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|   else
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|     Layout.VecAlign = DL.getABITypeAlignment(Layout.VecTy);
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|   Layout.ElemSize = DL.getTypeStoreSize(Layout.ElemTy);
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|   return true;
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| }
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| 
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| // Scalarize two-operand instruction I, using Split(Builder, X, Y, Name)
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| // to create an instruction like I with operands X and Y and name Name.
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| template<typename Splitter>
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| bool Scalarizer::splitBinary(Instruction &I, const Splitter &Split) {
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|   VectorType *VT = dyn_cast<VectorType>(I.getType());
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|   if (!VT)
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|     return false;
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| 
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|   unsigned NumElems = VT->getNumElements();
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|   IRBuilder<> Builder(&I);
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|   Scatterer Op0 = scatter(&I, I.getOperand(0));
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|   Scatterer Op1 = scatter(&I, I.getOperand(1));
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|   assert(Op0.size() == NumElems && "Mismatched binary operation");
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|   assert(Op1.size() == NumElems && "Mismatched binary operation");
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|   ValueVector Res;
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|   Res.resize(NumElems);
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|   for (unsigned Elem = 0; Elem < NumElems; ++Elem)
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|     Res[Elem] = Split(Builder, Op0[Elem], Op1[Elem],
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|                       I.getName() + ".i" + Twine(Elem));
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|   gather(&I, Res);
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|   return true;
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| }
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| 
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| bool Scalarizer::visitSelectInst(SelectInst &SI) {
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|   VectorType *VT = dyn_cast<VectorType>(SI.getType());
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|   if (!VT)
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|     return false;
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| 
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|   unsigned NumElems = VT->getNumElements();
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|   IRBuilder<> Builder(&SI);
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|   Scatterer Op1 = scatter(&SI, SI.getOperand(1));
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|   Scatterer Op2 = scatter(&SI, SI.getOperand(2));
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|   assert(Op1.size() == NumElems && "Mismatched select");
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|   assert(Op2.size() == NumElems && "Mismatched select");
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|   ValueVector Res;
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|   Res.resize(NumElems);
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| 
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|   if (SI.getOperand(0)->getType()->isVectorTy()) {
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|     Scatterer Op0 = scatter(&SI, SI.getOperand(0));
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|     assert(Op0.size() == NumElems && "Mismatched select");
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|     for (unsigned I = 0; I < NumElems; ++I)
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|       Res[I] = Builder.CreateSelect(Op0[I], Op1[I], Op2[I],
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|                                     SI.getName() + ".i" + Twine(I));
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|   } else {
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|     Value *Op0 = SI.getOperand(0);
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|     for (unsigned I = 0; I < NumElems; ++I)
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|       Res[I] = Builder.CreateSelect(Op0, Op1[I], Op2[I],
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|                                     SI.getName() + ".i" + Twine(I));
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|   }
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|   gather(&SI, Res);
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|   return true;
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| }
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| 
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| bool Scalarizer::visitICmpInst(ICmpInst &ICI) {
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|   return splitBinary(ICI, ICmpSplitter(ICI));
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| }
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| 
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| bool Scalarizer::visitFCmpInst(FCmpInst &FCI) {
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|   return splitBinary(FCI, FCmpSplitter(FCI));
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| }
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| 
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| bool Scalarizer::visitBinaryOperator(BinaryOperator &BO) {
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|   return splitBinary(BO, BinarySplitter(BO));
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| }
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| 
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| bool Scalarizer::visitGetElementPtrInst(GetElementPtrInst &GEPI) {
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|   VectorType *VT = dyn_cast<VectorType>(GEPI.getType());
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|   if (!VT)
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|     return false;
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| 
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|   IRBuilder<> Builder(&GEPI);
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|   unsigned NumElems = VT->getNumElements();
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|   unsigned NumIndices = GEPI.getNumIndices();
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| 
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|   Scatterer Base = scatter(&GEPI, GEPI.getOperand(0));
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| 
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|   SmallVector<Scatterer, 8> Ops;
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|   Ops.resize(NumIndices);
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|   for (unsigned I = 0; I < NumIndices; ++I)
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|     Ops[I] = scatter(&GEPI, GEPI.getOperand(I + 1));
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| 
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|   ValueVector Res;
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|   Res.resize(NumElems);
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|   for (unsigned I = 0; I < NumElems; ++I) {
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|     SmallVector<Value *, 8> Indices;
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|     Indices.resize(NumIndices);
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|     for (unsigned J = 0; J < NumIndices; ++J)
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|       Indices[J] = Ops[J][I];
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|     Res[I] = Builder.CreateGEP(GEPI.getSourceElementType(), Base[I], Indices,
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|                                GEPI.getName() + ".i" + Twine(I));
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|     if (GEPI.isInBounds())
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|       if (GetElementPtrInst *NewGEPI = dyn_cast<GetElementPtrInst>(Res[I]))
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|         NewGEPI->setIsInBounds();
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|   }
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|   gather(&GEPI, Res);
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|   return true;
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| }
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| 
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| bool Scalarizer::visitCastInst(CastInst &CI) {
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|   VectorType *VT = dyn_cast<VectorType>(CI.getDestTy());
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|   if (!VT)
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|     return false;
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| 
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|   unsigned NumElems = VT->getNumElements();
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|   IRBuilder<> Builder(&CI);
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|   Scatterer Op0 = scatter(&CI, CI.getOperand(0));
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|   assert(Op0.size() == NumElems && "Mismatched cast");
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|   ValueVector Res;
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|   Res.resize(NumElems);
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|   for (unsigned I = 0; I < NumElems; ++I)
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|     Res[I] = Builder.CreateCast(CI.getOpcode(), Op0[I], VT->getElementType(),
 | |
|                                 CI.getName() + ".i" + Twine(I));
 | |
|   gather(&CI, Res);
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| bool Scalarizer::visitBitCastInst(BitCastInst &BCI) {
 | |
|   VectorType *DstVT = dyn_cast<VectorType>(BCI.getDestTy());
 | |
|   VectorType *SrcVT = dyn_cast<VectorType>(BCI.getSrcTy());
 | |
|   if (!DstVT || !SrcVT)
 | |
|     return false;
 | |
| 
 | |
|   unsigned DstNumElems = DstVT->getNumElements();
 | |
|   unsigned SrcNumElems = SrcVT->getNumElements();
 | |
|   IRBuilder<> Builder(&BCI);
 | |
|   Scatterer Op0 = scatter(&BCI, BCI.getOperand(0));
 | |
|   ValueVector Res;
 | |
|   Res.resize(DstNumElems);
 | |
| 
 | |
|   if (DstNumElems == SrcNumElems) {
 | |
|     for (unsigned I = 0; I < DstNumElems; ++I)
 | |
|       Res[I] = Builder.CreateBitCast(Op0[I], DstVT->getElementType(),
 | |
|                                      BCI.getName() + ".i" + Twine(I));
 | |
|   } else if (DstNumElems > SrcNumElems) {
 | |
|     // <M x t1> -> <N*M x t2>.  Convert each t1 to <N x t2> and copy the
 | |
|     // individual elements to the destination.
 | |
|     unsigned FanOut = DstNumElems / SrcNumElems;
 | |
|     Type *MidTy = VectorType::get(DstVT->getElementType(), FanOut);
 | |
|     unsigned ResI = 0;
 | |
|     for (unsigned Op0I = 0; Op0I < SrcNumElems; ++Op0I) {
 | |
|       Value *V = Op0[Op0I];
 | |
|       Instruction *VI;
 | |
|       // Look through any existing bitcasts before converting to <N x t2>.
 | |
|       // In the best case, the resulting conversion might be a no-op.
 | |
|       while ((VI = dyn_cast<Instruction>(V)) &&
 | |
|              VI->getOpcode() == Instruction::BitCast)
 | |
|         V = VI->getOperand(0);
 | |
|       V = Builder.CreateBitCast(V, MidTy, V->getName() + ".cast");
 | |
|       Scatterer Mid = scatter(&BCI, V);
 | |
|       for (unsigned MidI = 0; MidI < FanOut; ++MidI)
 | |
|         Res[ResI++] = Mid[MidI];
 | |
|     }
 | |
|   } else {
 | |
|     // <N*M x t1> -> <M x t2>.  Convert each group of <N x t1> into a t2.
 | |
|     unsigned FanIn = SrcNumElems / DstNumElems;
 | |
|     Type *MidTy = VectorType::get(SrcVT->getElementType(), FanIn);
 | |
|     unsigned Op0I = 0;
 | |
|     for (unsigned ResI = 0; ResI < DstNumElems; ++ResI) {
 | |
|       Value *V = UndefValue::get(MidTy);
 | |
|       for (unsigned MidI = 0; MidI < FanIn; ++MidI)
 | |
|         V = Builder.CreateInsertElement(V, Op0[Op0I++], Builder.getInt32(MidI),
 | |
|                                         BCI.getName() + ".i" + Twine(ResI)
 | |
|                                         + ".upto" + Twine(MidI));
 | |
|       Res[ResI] = Builder.CreateBitCast(V, DstVT->getElementType(),
 | |
|                                         BCI.getName() + ".i" + Twine(ResI));
 | |
|     }
 | |
|   }
 | |
|   gather(&BCI, Res);
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| bool Scalarizer::visitShuffleVectorInst(ShuffleVectorInst &SVI) {
 | |
|   VectorType *VT = dyn_cast<VectorType>(SVI.getType());
 | |
|   if (!VT)
 | |
|     return false;
 | |
| 
 | |
|   unsigned NumElems = VT->getNumElements();
 | |
|   Scatterer Op0 = scatter(&SVI, SVI.getOperand(0));
 | |
|   Scatterer Op1 = scatter(&SVI, SVI.getOperand(1));
 | |
|   ValueVector Res;
 | |
|   Res.resize(NumElems);
 | |
| 
 | |
|   for (unsigned I = 0; I < NumElems; ++I) {
 | |
|     int Selector = SVI.getMaskValue(I);
 | |
|     if (Selector < 0)
 | |
|       Res[I] = UndefValue::get(VT->getElementType());
 | |
|     else if (unsigned(Selector) < Op0.size())
 | |
|       Res[I] = Op0[Selector];
 | |
|     else
 | |
|       Res[I] = Op1[Selector - Op0.size()];
 | |
|   }
 | |
|   gather(&SVI, Res);
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| bool Scalarizer::visitPHINode(PHINode &PHI) {
 | |
|   VectorType *VT = dyn_cast<VectorType>(PHI.getType());
 | |
|   if (!VT)
 | |
|     return false;
 | |
| 
 | |
|   unsigned NumElems = VT->getNumElements();
 | |
|   IRBuilder<> Builder(&PHI);
 | |
|   ValueVector Res;
 | |
|   Res.resize(NumElems);
 | |
| 
 | |
|   unsigned NumOps = PHI.getNumOperands();
 | |
|   for (unsigned I = 0; I < NumElems; ++I)
 | |
|     Res[I] = Builder.CreatePHI(VT->getElementType(), NumOps,
 | |
|                                PHI.getName() + ".i" + Twine(I));
 | |
| 
 | |
|   for (unsigned I = 0; I < NumOps; ++I) {
 | |
|     Scatterer Op = scatter(&PHI, PHI.getIncomingValue(I));
 | |
|     BasicBlock *IncomingBlock = PHI.getIncomingBlock(I);
 | |
|     for (unsigned J = 0; J < NumElems; ++J)
 | |
|       cast<PHINode>(Res[J])->addIncoming(Op[J], IncomingBlock);
 | |
|   }
 | |
|   gather(&PHI, Res);
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| bool Scalarizer::visitLoadInst(LoadInst &LI) {
 | |
|   if (!ScalarizeLoadStore)
 | |
|     return false;
 | |
|   if (!LI.isSimple())
 | |
|     return false;
 | |
| 
 | |
|   VectorLayout Layout;
 | |
|   if (!getVectorLayout(LI.getType(), LI.getAlignment(), Layout,
 | |
|                        LI.getModule()->getDataLayout()))
 | |
|     return false;
 | |
| 
 | |
|   unsigned NumElems = Layout.VecTy->getNumElements();
 | |
|   IRBuilder<> Builder(&LI);
 | |
|   Scatterer Ptr = scatter(&LI, LI.getPointerOperand());
 | |
|   ValueVector Res;
 | |
|   Res.resize(NumElems);
 | |
| 
 | |
|   for (unsigned I = 0; I < NumElems; ++I)
 | |
|     Res[I] = Builder.CreateAlignedLoad(Ptr[I], Layout.getElemAlign(I),
 | |
|                                        LI.getName() + ".i" + Twine(I));
 | |
|   gather(&LI, Res);
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| bool Scalarizer::visitStoreInst(StoreInst &SI) {
 | |
|   if (!ScalarizeLoadStore)
 | |
|     return false;
 | |
|   if (!SI.isSimple())
 | |
|     return false;
 | |
| 
 | |
|   VectorLayout Layout;
 | |
|   Value *FullValue = SI.getValueOperand();
 | |
|   if (!getVectorLayout(FullValue->getType(), SI.getAlignment(), Layout,
 | |
|                        SI.getModule()->getDataLayout()))
 | |
|     return false;
 | |
| 
 | |
|   unsigned NumElems = Layout.VecTy->getNumElements();
 | |
|   IRBuilder<> Builder(&SI);
 | |
|   Scatterer Ptr = scatter(&SI, SI.getPointerOperand());
 | |
|   Scatterer Val = scatter(&SI, FullValue);
 | |
| 
 | |
|   ValueVector Stores;
 | |
|   Stores.resize(NumElems);
 | |
|   for (unsigned I = 0; I < NumElems; ++I) {
 | |
|     unsigned Align = Layout.getElemAlign(I);
 | |
|     Stores[I] = Builder.CreateAlignedStore(Val[I], Ptr[I], Align);
 | |
|   }
 | |
|   transferMetadata(&SI, Stores);
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| // Delete the instructions that we scalarized.  If a full vector result
 | |
| // is still needed, recreate it using InsertElements.
 | |
| bool Scalarizer::finish() {
 | |
|   // The presence of data in Gathered or Scattered indicates changes
 | |
|   // made to the Function.
 | |
|   if (Gathered.empty() && Scattered.empty())
 | |
|     return false;
 | |
|   for (GatherList::iterator GMI = Gathered.begin(), GME = Gathered.end();
 | |
|        GMI != GME; ++GMI) {
 | |
|     Instruction *Op = GMI->first;
 | |
|     ValueVector &CV = *GMI->second;
 | |
|     if (!Op->use_empty()) {
 | |
|       // The value is still needed, so recreate it using a series of
 | |
|       // InsertElements.
 | |
|       Type *Ty = Op->getType();
 | |
|       Value *Res = UndefValue::get(Ty);
 | |
|       BasicBlock *BB = Op->getParent();
 | |
|       unsigned Count = Ty->getVectorNumElements();
 | |
|       IRBuilder<> Builder(Op);
 | |
|       if (isa<PHINode>(Op))
 | |
|         Builder.SetInsertPoint(BB, BB->getFirstInsertionPt());
 | |
|       for (unsigned I = 0; I < Count; ++I)
 | |
|         Res = Builder.CreateInsertElement(Res, CV[I], Builder.getInt32(I),
 | |
|                                           Op->getName() + ".upto" + Twine(I));
 | |
|       Res->takeName(Op);
 | |
|       Op->replaceAllUsesWith(Res);
 | |
|     }
 | |
|     Op->eraseFromParent();
 | |
|   }
 | |
|   Gathered.clear();
 | |
|   Scattered.clear();
 | |
|   return true;
 | |
| }
 | |
| 
 | |
| FunctionPass *llvm::createScalarizerPass() {
 | |
|   return new Scalarizer();
 | |
| }
 |