LLVM  13.0.0git
SLPVectorizer.h
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1 //===- SLPVectorizer.h ------------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 // This pass implements the Bottom Up SLP vectorizer. It detects consecutive
9 // stores that can be put together into vector-stores. Next, it attempts to
10 // construct vectorizable tree using the use-def chains. If a profitable tree
11 // was found, the SLP vectorizer performs vectorization on the tree.
12 //
13 // The pass is inspired by the work described in the paper:
14 // "Loop-Aware SLP in GCC" by Ira Rosen, Dorit Nuzman, Ayal Zaks.
15 //
16 //===----------------------------------------------------------------------===//
17 
18 #ifndef LLVM_TRANSFORMS_VECTORIZE_SLPVECTORIZER_H
19 #define LLVM_TRANSFORMS_VECTORIZE_SLPVECTORIZER_H
20 
21 #include "llvm/ADT/ArrayRef.h"
22 #include "llvm/ADT/MapVector.h"
23 #include "llvm/ADT/None.h"
24 #include "llvm/ADT/SmallVector.h"
25 #include "llvm/IR/PassManager.h"
26 
27 namespace llvm {
28 
29 class AAResults;
30 class AssumptionCache;
31 class BasicBlock;
32 class CmpInst;
33 class DataLayout;
34 class DemandedBits;
35 class DominatorTree;
36 class Function;
37 class GetElementPtrInst;
38 class InsertElementInst;
39 class InsertValueInst;
40 class Instruction;
41 class LoopInfo;
42 class OptimizationRemarkEmitter;
43 class PHINode;
44 class ScalarEvolution;
45 class StoreInst;
46 class TargetLibraryInfo;
47 class TargetTransformInfo;
48 class Value;
49 
50 /// A private "module" namespace for types and utilities used by this pass.
51 /// These are implementation details and should not be used by clients.
52 namespace slpvectorizer {
53 
54 class BoUpSLP;
55 
56 } // end namespace slpvectorizer
57 
58 struct SLPVectorizerPass : public PassInfoMixin<SLPVectorizerPass> {
63 
64  ScalarEvolution *SE = nullptr;
66  TargetLibraryInfo *TLI = nullptr;
67  AAResults *AA = nullptr;
68  LoopInfo *LI = nullptr;
69  DominatorTree *DT = nullptr;
70  AssumptionCache *AC = nullptr;
71  DemandedBits *DB = nullptr;
72  const DataLayout *DL = nullptr;
73 
74 public:
76 
77  // Glue for old PM.
79  TargetLibraryInfo *TLI_, AAResults *AA_, LoopInfo *LI_,
82 
83 private:
84  /// Collect store and getelementptr instructions and organize them
85  /// according to the underlying object of their pointer operands. We sort the
86  /// instructions by their underlying objects to reduce the cost of
87  /// consecutive access queries.
88  ///
89  /// TODO: We can further reduce this cost if we flush the chain creation
90  /// every time we run into a memory barrier.
91  void collectSeedInstructions(BasicBlock *BB);
92 
93  /// Try to vectorize a chain that starts at two arithmetic instrs.
94  bool tryToVectorizePair(Value *A, Value *B, slpvectorizer::BoUpSLP &R);
95 
96  /// Try to vectorize a list of operands.
97  /// When \p InsertUses is provided and its entries are non-zero
98  /// then users of \p VL are known to be InsertElement instructions
99  /// each associated with same VL entry index. Their cost is then
100  /// used to adjust cost of the vectorization assuming instcombine pass
101  /// then optimizes ExtractElement-InsertElement sequence.
102  /// \returns true if a value was vectorized.
103  bool tryToVectorizeList(ArrayRef<Value *> VL, slpvectorizer::BoUpSLP &R,
104  bool AllowReorder = false,
105  ArrayRef<Value *> InsertUses = None);
106 
107  /// Try to vectorize a chain that may start at the operands of \p I.
108  bool tryToVectorize(Instruction *I, slpvectorizer::BoUpSLP &R);
109 
110  /// Vectorize the store instructions collected in Stores.
111  bool vectorizeStoreChains(slpvectorizer::BoUpSLP &R);
112 
113  /// Vectorize the index computations of the getelementptr instructions
114  /// collected in GEPs.
115  bool vectorizeGEPIndices(BasicBlock *BB, slpvectorizer::BoUpSLP &R);
116 
117  /// Try to find horizontal reduction or otherwise vectorize a chain of binary
118  /// operators.
119  bool vectorizeRootInstruction(PHINode *P, Value *V, BasicBlock *BB,
122 
123  /// Try to vectorize trees that start at insertvalue instructions.
124  bool vectorizeInsertValueInst(InsertValueInst *IVI, BasicBlock *BB,
126 
127  /// Try to vectorize trees that start at insertelement instructions.
128  bool vectorizeInsertElementInst(InsertElementInst *IEI, BasicBlock *BB,
130 
131  /// Tries to vectorize constructs started from CmpInst, InsertValueInst or
132  /// InsertElementInst instructions.
133  bool vectorizeSimpleInstructions(SmallVectorImpl<Instruction *> &Instructions,
135  bool AtTerminator);
136 
137  /// Scan the basic block and look for patterns that are likely to start
138  /// a vectorization chain.
139  bool vectorizeChainsInBlock(BasicBlock *BB, slpvectorizer::BoUpSLP &R);
140 
141  bool vectorizeStoreChain(ArrayRef<Value *> Chain, slpvectorizer::BoUpSLP &R,
142  unsigned Idx);
143 
144  bool vectorizeStores(ArrayRef<StoreInst *> Stores, slpvectorizer::BoUpSLP &R);
145 
146  /// The store instructions in a basic block organized by base pointer.
147  StoreListMap Stores;
148 
149  /// The getelementptr instructions in a basic block organized by base pointer.
150  GEPListMap GEPs;
151 };
152 
153 } // end namespace llvm
154 
155 #endif // LLVM_TRANSFORMS_VECTORIZE_SLPVECTORIZER_H
llvm::PreservedAnalyses
A set of analyses that are preserved following a run of a transformation pass.
Definition: PassManager.h:155
llvm::SLPVectorizerPass::AC
AssumptionCache * AC
Definition: SLPVectorizer.h:70
llvm
Definition: AllocatorList.h:23
llvm::DataLayout
A parsed version of the target data layout string in and methods for querying it.
Definition: DataLayout.h:112
llvm::PassInfoMixin
A CRTP mix-in to automatically provide informational APIs needed for passes.
Definition: PassManager.h:374
llvm::Function
Definition: Function.h:61
P
This currently compiles esp xmm0 movsd esp eax eax esp ret We should use not the dag combiner This is because dagcombine2 needs to be able to see through the X86ISD::Wrapper which DAGCombine can t really do The code for turning x load into a single vector load is target independent and should be moved to the dag combiner The code for turning x load into a vector load can only handle a direct load from a global or a direct load from the stack It should be generalized to handle any load from P
Definition: README-SSE.txt:411
llvm::SmallVector
This is a 'vector' (really, a variable-sized array), optimized for the case when the array is small.
Definition: SmallVector.h:1168
llvm::TargetTransformInfo
This pass provides access to the codegen interfaces that are needed for IR-level transformations.
Definition: TargetTransformInfo.h:167
MapVector.h
llvm::ScalarEvolution
The main scalar evolution driver.
Definition: ScalarEvolution.h:443
llvm::DominatorTree
Concrete subclass of DominatorTreeBase that is used to compute a normal dominator tree.
Definition: Dominators.h:151
Instructions
Code Generation Notes for reduce the size of the ISel and reduce repetition in the implementation In a small number of this can cause even when no optimisation has taken place Instructions
Definition: MSA.txt:11
llvm::MapVector< Value *, StoreList >
llvm::SLPVectorizerPass
Definition: SLPVectorizer.h:58
F
#define F(x, y, z)
Definition: MD5.cpp:56
llvm::BasicBlock
LLVM Basic Block Representation.
Definition: BasicBlock.h:58
llvm::SLPVectorizerPass::runImpl
bool runImpl(Function &F, ScalarEvolution *SE_, TargetTransformInfo *TTI_, TargetLibraryInfo *TLI_, AAResults *AA_, LoopInfo *LI_, DominatorTree *DT_, AssumptionCache *AC_, DemandedBits *DB_, OptimizationRemarkEmitter *ORE_)
Definition: SLPVectorizer.cpp:6207
llvm::AAResults
Definition: AliasAnalysis.h:456
llvm::SLPVectorizerPass::DL
const DataLayout * DL
Definition: SLPVectorizer.h:72
llvm::InsertElementInst
This instruction inserts a single (scalar) element into a VectorType value.
Definition: Instructions.h:1914
B
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
llvm::Instruction
Definition: Instruction.h:45
llvm::None
const NoneType None
Definition: None.h:23
llvm::SLPVectorizerPass::AA
AAResults * AA
Definition: SLPVectorizer.h:67
llvm::DemandedBits
Definition: DemandedBits.h:40
I
#define I(x, y, z)
Definition: MD5.cpp:59
ArrayRef.h
llvm::SLPVectorizerPass::LI
LoopInfo * LI
Definition: SLPVectorizer.h:68
llvm::SLPVectorizerPass::TLI
TargetLibraryInfo * TLI
Definition: SLPVectorizer.h:66
llvm::ISD::BasicBlock
@ BasicBlock
Various leaf nodes.
Definition: ISDOpcodes.h:64
llvm::ArrayRef
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: APInt.h:32
llvm::LoopInfo
Definition: LoopInfo.h:1080
None.h
llvm::OptimizationRemarkEmitter
The optimization diagnostic interface.
Definition: OptimizationRemarkEmitter.h:33
llvm::SLPVectorizerPass::run
PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM)
Definition: SLPVectorizer.cpp:6185
llvm::AssumptionCache
A cache of @llvm.assume calls within a function.
Definition: AssumptionCache.h:41
llvm::SLPVectorizerPass::DB
DemandedBits * DB
Definition: SLPVectorizer.h:71
llvm::slpvectorizer::BoUpSLP
Bottom Up SLP Vectorizer.
Definition: SLPVectorizer.cpp:548
llvm::SLPVectorizerPass::SE
ScalarEvolution * SE
Definition: SLPVectorizer.h:64
llvm::TargetStackID::Value
Value
Definition: TargetFrameLowering.h:27
PassManager.h
llvm::TargetLibraryInfo
Provides information about what library functions are available for the current target.
Definition: TargetLibraryInfo.h:207
SmallVector.h
llvm::PHINode
Definition: Instructions.h:2572
llvm::SmallVectorImpl< Instruction * >
llvm::AnalysisManager
A container for analyses that lazily runs them and caches their results.
Definition: InstructionSimplify.h:44
BB
Common register allocation spilling lr str ldr sxth r3 ldr mla r4 can lr mov lr str ldr sxth r3 mla r4 and then merge mul and lr str ldr sxth r3 mla r4 It also increase the likelihood the store may become dead bb27 Successors according to LLVM BB
Definition: README.txt:39
llvm::InsertValueInst
This instruction inserts a struct field of array element value into an aggregate value.
Definition: Instructions.h:2429
llvm::SLPVectorizerPass::DT
DominatorTree * DT
Definition: SLPVectorizer.h:69
llvm::Value
LLVM Value Representation.
Definition: Value.h:75
llvm::codeview::PublicSymFlags::Function
@ Function