LLVM  14.0.0git
LazyValueInfo.h
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1 //===- LazyValueInfo.h - Value constraint analysis --------------*- 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 //
9 // This file defines the interface for lazy computation of value constraint
10 // information.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_ANALYSIS_LAZYVALUEINFO_H
15 #define LLVM_ANALYSIS_LAZYVALUEINFO_H
16 
17 #include "llvm/IR/PassManager.h"
18 #include "llvm/Pass.h"
19 
20 namespace llvm {
21  class AssumptionCache;
22  class Constant;
23  class ConstantRange;
24  class DataLayout;
25  class DominatorTree;
26  class Instruction;
27  class TargetLibraryInfo;
28  class Value;
29 
30 /// This pass computes, caches, and vends lazy value constraint information.
33  AssumptionCache *AC = nullptr;
34  const DataLayout *DL = nullptr;
35  class TargetLibraryInfo *TLI = nullptr;
36  void *PImpl = nullptr;
37  LazyValueInfo(const LazyValueInfo&) = delete;
38  void operator=(const LazyValueInfo&) = delete;
39 public:
43  TargetLibraryInfo *TLI_)
44  : AC(AC_), DL(DL_), TLI(TLI_) {}
46  : AC(Arg.AC), DL(Arg.DL), TLI(Arg.TLI), PImpl(Arg.PImpl) {
47  Arg.PImpl = nullptr;
48  }
50  releaseMemory();
51  AC = Arg.AC;
52  DL = Arg.DL;
53  TLI = Arg.TLI;
54  PImpl = Arg.PImpl;
55  Arg.PImpl = nullptr;
56  return *this;
57  }
58 
59  /// This is used to return true/false/dunno results.
60  enum Tristate {
61  Unknown = -1, False = 0, True = 1
62  };
63 
64  // Public query interface.
65 
66  /// Determine whether the specified value comparison with a constant is known
67  /// to be true or false on the specified CFG edge.
68  /// Pred is a CmpInst predicate.
69  Tristate getPredicateOnEdge(unsigned Pred, Value *V, Constant *C,
70  BasicBlock *FromBB, BasicBlock *ToBB,
71  Instruction *CxtI = nullptr);
72 
73  /// Determine whether the specified value comparison with a constant is known
74  /// to be true or false at the specified instruction.
75  /// \p Pred is a CmpInst predicate. If \p UseBlockValue is true, the block
76  /// value is also taken into account.
77  Tristate getPredicateAt(unsigned Pred, Value *V, Constant *C,
78  Instruction *CxtI, bool UseBlockValue);
79 
80  /// Determine whether the specified value comparison is known to be true
81  /// or false at the specified instruction. While this takes two Value's,
82  /// it still requires that one of them is a constant.
83  /// \p Pred is a CmpInst predicate.
84  /// If \p UseBlockValue is true, the block value is also taken into account.
85  Tristate getPredicateAt(unsigned Pred, Value *LHS, Value *RHS,
86  Instruction *CxtI, bool UseBlockValue);
87 
88  /// Determine whether the specified value is known to be a constant at the
89  /// specified instruction. Return null if not.
91 
92  /// Return the ConstantRange constraint that is known to hold for the
93  /// specified value at the specified instruction. This may only be called
94  /// on integer-typed Values.
96  bool UndefAllowed = true);
97 
98  /// Determine whether the specified value is known to be a
99  /// constant on the specified edge. Return null if not.
101  Instruction *CxtI = nullptr);
102 
103  /// Return the ConstantRage constraint that is known to hold for the
104  /// specified value on the specified edge. This may be only be called
105  /// on integer-typed Values.
107  BasicBlock *ToBB,
108  Instruction *CxtI = nullptr);
109 
110  /// Inform the analysis cache that we have threaded an edge from
111  /// PredBB to OldSucc to be from PredBB to NewSucc instead.
112  void threadEdge(BasicBlock *PredBB, BasicBlock *OldSucc, BasicBlock *NewSucc);
113 
114  /// Inform the analysis cache that we have erased a block.
115  void eraseBlock(BasicBlock *BB);
116 
117  /// Print the \LazyValueInfo Analysis.
118  /// We pass in the DTree that is required for identifying which basic blocks
119  /// we can solve/print for, in the LVIPrinter.
120  void printLVI(Function &F, DominatorTree &DTree, raw_ostream &OS);
121 
122  // For old PM pass. Delete once LazyValueInfoWrapperPass is gone.
123  void releaseMemory();
124 
125  /// Handle invalidation events in the new pass manager.
126  bool invalidate(Function &F, const PreservedAnalyses &PA,
128 };
129 
130 /// Analysis to compute lazy value information.
131 class LazyValueAnalysis : public AnalysisInfoMixin<LazyValueAnalysis> {
132 public:
135 
136 private:
137  static AnalysisKey Key;
139 };
140 
141 /// Wrapper around LazyValueInfo.
144  void operator=(const LazyValueInfoWrapperPass&) = delete;
145 public:
146  static char ID;
149  assert(!Info.PImpl && "releaseMemory not called");
150  }
151 
153 
154  void getAnalysisUsage(AnalysisUsage &AU) const override;
155  void releaseMemory() override;
156  bool runOnFunction(Function &F) override;
157 private:
158  LazyValueInfo Info;
159 };
160 
161 } // end namespace llvm
162 
163 #endif
164 
llvm::LazyValueInfo::getConstantOnEdge
Constant * getConstantOnEdge(Value *V, BasicBlock *FromBB, BasicBlock *ToBB, Instruction *CxtI=nullptr)
Determine whether the specified value is known to be a constant on the specified edge.
Definition: LazyValueInfo.cpp:1622
llvm::PreservedAnalyses
A set of analyses that are preserved following a run of a transformation pass.
Definition: PassManager.h:155
llvm::LazyValueInfo::~LazyValueInfo
~LazyValueInfo()
Definition: LazyValueInfo.cpp:1538
llvm
---------------------— PointerInfo ------------------------------------—
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::LazyValueInfo::getPredicateOnEdge
Tristate getPredicateOnEdge(unsigned Pred, Value *V, Constant *C, BasicBlock *FromBB, BasicBlock *ToBB, Instruction *CxtI=nullptr)
Determine whether the specified value comparison with a constant is known to be true or false on the ...
Definition: LazyValueInfo.cpp:1727
llvm::Function
Definition: Function.h:61
Pass.h
llvm::LazyValueAnalysis
Analysis to compute lazy value information.
Definition: LazyValueInfo.h:131
llvm::LazyValueInfo::getConstantRangeOnEdge
ConstantRange getConstantRangeOnEdge(Value *V, BasicBlock *FromBB, BasicBlock *ToBB, Instruction *CxtI=nullptr)
Return the ConstantRage constraint that is known to hold for the specified value on the specified edg...
Definition: LazyValueInfo.cpp:1639
llvm::DominatorTree
Concrete subclass of DominatorTreeBase that is used to compute a normal dominator tree.
Definition: Dominators.h:151
FAM
FunctionAnalysisManager FAM
Definition: PassBuilderBindings.cpp:59
llvm::LazyValueInfo::getConstant
Constant * getConstant(Value *V, Instruction *CxtI)
Determine whether the specified value is known to be a constant at the specified instruction.
Definition: LazyValueInfo.cpp:1583
F
#define F(x, y, z)
Definition: MD5.cpp:56
llvm::LazyValueAnalysis::run
Result run(Function &F, FunctionAnalysisManager &FAM)
Definition: LazyValueInfo.cpp:1561
llvm::BasicBlock
LLVM Basic Block Representation.
Definition: BasicBlock.h:58
Arg
amdgpu Simplify well known AMD library false FunctionCallee Value * Arg
Definition: AMDGPULibCalls.cpp:206
llvm::LazyValueInfoWrapperPass::~LazyValueInfoWrapperPass
~LazyValueInfoWrapperPass() override
Definition: LazyValueInfo.h:148
llvm::ISD::Constant
@ Constant
Definition: ISDOpcodes.h:76
llvm::LazyValueInfo::Unknown
@ Unknown
Definition: LazyValueInfo.h:61
C
(vector float) vec_cmpeq(*A, *B) C
Definition: README_ALTIVEC.txt:86
llvm::LazyValueInfoWrapperPass::ID
static char ID
Definition: LazyValueInfo.h:146
llvm::AnalysisUsage
Represent the analysis usage information of a pass.
Definition: PassAnalysisSupport.h:47
llvm::LazyValueInfo::LazyValueInfo
LazyValueInfo(LazyValueInfo &&Arg)
Definition: LazyValueInfo.h:45
llvm::LazyValueInfo::True
@ True
Definition: LazyValueInfo.h:61
llvm::Instruction
Definition: Instruction.h:45
llvm::LazyValueInfo::printLVI
void printLVI(Function &F, DominatorTree &DTree, raw_ostream &OS)
Print the \LazyValueInfo Analysis.
Definition: LazyValueInfo.cpp:1875
llvm::raw_ostream
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:53
llvm::LazyValueInfoWrapperPass::getAnalysisUsage
void getAnalysisUsage(AnalysisUsage &AU) const override
getAnalysisUsage - This function should be overriden by passes that need analysis information to do t...
Definition: LazyValueInfo.cpp:1530
llvm::AnalysisManager::Invalidator
API to communicate dependencies between analyses during invalidation.
Definition: PassManager.h:656
llvm::LazyValueInfoWrapperPass::runOnFunction
bool runOnFunction(Function &F) override
runOnFunction - Virtual method overriden by subclasses to do the per-function processing of the pass.
Definition: LazyValueInfo.cpp:1519
llvm::LazyValueInfo::invalidate
bool invalidate(Function &F, const PreservedAnalyses &PA, FunctionAnalysisManager::Invalidator &Inv)
Handle invalidation events in the new pass manager.
Definition: LazyValueInfo.cpp:1548
llvm::Constant
This is an important base class in LLVM.
Definition: Constant.h:41
llvm::LazyValueInfo::getConstantRange
ConstantRange getConstantRange(Value *V, Instruction *CxtI, bool UndefAllowed=true)
Return the ConstantRange constraint that is known to hold for the specified value at the specified in...
Definition: LazyValueInfo.cpp:1602
llvm::LazyValueInfoWrapperPass
Wrapper around LazyValueInfo.
Definition: LazyValueInfo.h:142
llvm::AnalysisKey
A special type used by analysis passes to provide an address that identifies that particular analysis...
Definition: PassManager.h:72
assert
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
llvm::LazyValueInfo
This pass computes, caches, and vends lazy value constraint information.
Definition: LazyValueInfo.h:31
llvm::AnalysisInfoMixin
A CRTP mix-in that provides informational APIs needed for analysis passes.
Definition: PassManager.h:391
llvm::LazyValueInfo::releaseMemory
void releaseMemory()
Definition: LazyValueInfo.cpp:1540
llvm::AssumptionCache
A cache of @llvm.assume calls within a function.
Definition: AssumptionCache.h:41
llvm::LazyValueInfo::operator=
LazyValueInfo & operator=(LazyValueInfo &&Arg)
Definition: LazyValueInfo.h:49
llvm::LazyValueInfoWrapperPass::LazyValueInfoWrapperPass
LazyValueInfoWrapperPass()
Definition: LazyValueInfo.cpp:52
llvm::LazyValueAnalysis::Result
LazyValueInfo Result
Definition: LazyValueInfo.h:133
llvm::LazyValueInfo::LazyValueInfo
LazyValueInfo()
Definition: LazyValueInfo.h:41
DL
MachineBasicBlock MachineBasicBlock::iterator DebugLoc DL
Definition: AArch64SLSHardening.cpp:76
llvm::LazyValueInfoWrapperPass::releaseMemory
void releaseMemory() override
releaseMemory() - This member can be implemented by a pass if it wants to be able to release its memo...
Definition: LazyValueInfo.cpp:1559
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:219
llvm::LazyValueInfoWrapperPass::getLVI
LazyValueInfo & getLVI()
Definition: LazyValueInfo.cpp:1536
llvm::ConstantRange
This class represents a range of values.
Definition: ConstantRange.h:47
llvm::LazyValueInfo::LazyValueInfo
LazyValueInfo(AssumptionCache *AC_, const DataLayout *DL_, TargetLibraryInfo *TLI_)
Definition: LazyValueInfo.h:42
llvm::LazyValueInfo::Tristate
Tristate
This is used to return true/false/dunno results.
Definition: LazyValueInfo.h:60
llvm::AnalysisManager
A container for analyses that lazily runs them and caches their results.
Definition: InstructionSimplify.h:44
llvm::FunctionPass
FunctionPass class - This class is used to implement most global optimizations.
Definition: Pass.h:298
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::LazyValueInfo::False
@ False
Definition: LazyValueInfo.h:61
llvm::LazyValueInfo::eraseBlock
void eraseBlock(BasicBlock *BB)
Inform the analysis cache that we have erased a block.
Definition: LazyValueInfo.cpp:1868
llvm::LazyValueInfo::getPredicateAt
Tristate getPredicateAt(unsigned Pred, Value *V, Constant *C, Instruction *CxtI, bool UseBlockValue)
Determine whether the specified value comparison with a constant is known to be true or false at the ...
Definition: LazyValueInfo.cpp:1738
llvm::Value
LLVM Value Representation.
Definition: Value.h:75
llvm::LazyValueInfo::threadEdge
void threadEdge(BasicBlock *PredBB, BasicBlock *OldSucc, BasicBlock *NewSucc)
Inform the analysis cache that we have threaded an edge from PredBB to OldSucc to be from PredBB to N...
Definition: LazyValueInfo.cpp:1860