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//===- SLPVectorizer.h ------------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// This pass implements the Bottom Up SLP vectorizer. It detects consecutive
// stores that can be put together into vector-stores. Next, it attempts to
// construct vectorizable tree using the use-def chains. If a profitable tree
// was found, the SLP vectorizer performs vectorization on the tree.
//
// The pass is inspired by the work described in the paper:
// "Loop-Aware SLP in GCC" by Ira Rosen, Dorit Nuzman, Ayal Zaks.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TRANSFORMS_VECTORIZE_SLPVECTORIZER_H
#define LLVM_TRANSFORMS_VECTORIZE_SLPVECTORIZER_H
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/None.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/IR/PassManager.h"
#include "llvm/IR/ValueHandle.h"
namespace llvm {
class AssumptionCache;
class BasicBlock;
class CmpInst;
class DataLayout;
class DemandedBits;
class DominatorTree;
class Function;
class InsertElementInst;
class InsertValueInst;
class Instruction;
class LoopInfo;
class OptimizationRemarkEmitter;
class PHINode;
class ScalarEvolution;
class StoreInst;
class TargetLibraryInfo;
class TargetTransformInfo;
class Value;
/// A private "module" namespace for types and utilities used by this pass.
/// These are implementation details and should not be used by clients.
namespace slpvectorizer {
class BoUpSLP;
} // end namespace slpvectorizer
extern cl::opt<bool> RunSLPVectorization;
struct SLPVectorizerPass : public PassInfoMixin<SLPVectorizerPass> {
using StoreList = SmallVector<StoreInst *, 8>;
using StoreListMap = MapVector<Value *, StoreList>;
using WeakTrackingVHList = SmallVector<WeakTrackingVH, 8>;
using WeakTrackingVHListMap = MapVector<Value *, WeakTrackingVHList>;
ScalarEvolution *SE = nullptr;
TargetTransformInfo *TTI = nullptr;
TargetLibraryInfo *TLI = nullptr;
AliasAnalysis *AA = nullptr;
LoopInfo *LI = nullptr;
DominatorTree *DT = nullptr;
AssumptionCache *AC = nullptr;
DemandedBits *DB = nullptr;
const DataLayout *DL = nullptr;
public:
PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
// Glue for old PM.
bool runImpl(Function &F, ScalarEvolution *SE_, TargetTransformInfo *TTI_,
TargetLibraryInfo *TLI_, AliasAnalysis *AA_, LoopInfo *LI_,
DominatorTree *DT_, AssumptionCache *AC_, DemandedBits *DB_,
OptimizationRemarkEmitter *ORE_);
private:
/// Collect store and getelementptr instructions and organize them
/// according to the underlying object of their pointer operands. We sort the
/// instructions by their underlying objects to reduce the cost of
/// consecutive access queries.
///
/// TODO: We can further reduce this cost if we flush the chain creation
/// every time we run into a memory barrier.
void collectSeedInstructions(BasicBlock *BB);
/// Try to vectorize a chain that starts at two arithmetic instrs.
bool tryToVectorizePair(Value *A, Value *B, slpvectorizer::BoUpSLP &R);
/// Try to vectorize a list of operands.
/// \param UserCost Cost of the user operations of \p VL if they may affect
/// the cost of the vectorization.
/// \returns true if a value was vectorized.
bool tryToVectorizeList(ArrayRef<Value *> VL, slpvectorizer::BoUpSLP &R,
int UserCost = 0, bool AllowReorder = false);
/// Try to vectorize a chain that may start at the operands of \p I.
bool tryToVectorize(Instruction *I, slpvectorizer::BoUpSLP &R);
/// Vectorize the store instructions collected in Stores.
bool vectorizeStoreChains(slpvectorizer::BoUpSLP &R);
/// Vectorize the index computations of the getelementptr instructions
/// collected in GEPs.
bool vectorizeGEPIndices(BasicBlock *BB, slpvectorizer::BoUpSLP &R);
/// Try to find horizontal reduction or otherwise vectorize a chain of binary
/// operators.
bool vectorizeRootInstruction(PHINode *P, Value *V, BasicBlock *BB,
slpvectorizer::BoUpSLP &R,
TargetTransformInfo *TTI);
/// Try to vectorize trees that start at insertvalue instructions.
bool vectorizeInsertValueInst(InsertValueInst *IVI, BasicBlock *BB,
slpvectorizer::BoUpSLP &R);
/// Try to vectorize trees that start at insertelement instructions.
bool vectorizeInsertElementInst(InsertElementInst *IEI, BasicBlock *BB,
slpvectorizer::BoUpSLP &R);
/// Try to vectorize trees that start at compare instructions.
bool vectorizeCmpInst(CmpInst *CI, BasicBlock *BB, slpvectorizer::BoUpSLP &R);
/// Tries to vectorize constructs started from CmpInst, InsertValueInst or
/// InsertElementInst instructions.
bool vectorizeSimpleInstructions(SmallVectorImpl<WeakVH> &Instructions,
BasicBlock *BB, slpvectorizer::BoUpSLP &R);
/// Scan the basic block and look for patterns that are likely to start
/// a vectorization chain.
bool vectorizeChainsInBlock(BasicBlock *BB, slpvectorizer::BoUpSLP &R);
bool vectorizeStoreChain(ArrayRef<Value *> Chain, slpvectorizer::BoUpSLP &R,
unsigned VecRegSize);
bool vectorizeStores(ArrayRef<StoreInst *> Stores, slpvectorizer::BoUpSLP &R);
/// The store instructions in a basic block organized by base pointer.
StoreListMap Stores;
/// The getelementptr instructions in a basic block organized by base pointer.
WeakTrackingVHListMap GEPs;
};
} // end namespace llvm
#endif // LLVM_TRANSFORMS_VECTORIZE_SLPVECTORIZER_H