LLVM  10.0.0svn
PseudoSourceValue.h
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1 //===-- llvm/CodeGen/PseudoSourceValue.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 //
9 // This file contains the declaration of the PseudoSourceValue class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CODEGEN_PSEUDOSOURCEVALUE_H
14 #define LLVM_CODEGEN_PSEUDOSOURCEVALUE_H
15 
16 #include "llvm/ADT/StringMap.h"
17 #include "llvm/IR/GlobalValue.h"
18 #include "llvm/IR/ValueMap.h"
19 #include <map>
20 
21 namespace llvm {
22 
23 class MachineFrameInfo;
24 class MachineMemOperand;
25 class raw_ostream;
26 class TargetInstrInfo;
27 
28 raw_ostream &operator<<(raw_ostream &OS, const MachineMemOperand &MMO);
29 class PseudoSourceValue;
30 raw_ostream &operator<<(raw_ostream &OS, const PseudoSourceValue* PSV);
31 
32 /// Special value supplied for machine level alias analysis. It indicates that
33 /// a memory access references the functions stack frame (e.g., a spill slot),
34 /// below the stack frame (e.g., argument space), or constant pool.
36 public:
37  enum PSVKind : unsigned {
39  GOT,
46  };
47 
48 private:
49  unsigned Kind;
50  unsigned AddressSpace;
52  const PseudoSourceValue* PSV);
53 
54  friend class MachineMemOperand; // For printCustom().
55 
56  /// Implement printing for PseudoSourceValue. This is called from
57  /// Value::print or Value's operator<<.
58  virtual void printCustom(raw_ostream &O) const;
59 
60 public:
61  explicit PseudoSourceValue(unsigned Kind, const TargetInstrInfo &TII);
62 
63  virtual ~PseudoSourceValue();
64 
65  unsigned kind() const { return Kind; }
66 
67  bool isStack() const { return Kind == Stack; }
68  bool isGOT() const { return Kind == GOT; }
69  bool isConstantPool() const { return Kind == ConstantPool; }
70  bool isJumpTable() const { return Kind == JumpTable; }
71 
72  unsigned getAddressSpace() const { return AddressSpace; }
73 
74  unsigned getTargetCustom() const {
75  return (Kind >= TargetCustom) ? ((Kind+1) - TargetCustom) : 0;
76  }
77 
78  /// Test whether the memory pointed to by this PseudoSourceValue has a
79  /// constant value.
80  virtual bool isConstant(const MachineFrameInfo *) const;
81 
82  /// Test whether the memory pointed to by this PseudoSourceValue may also be
83  /// pointed to by an LLVM IR Value.
84  virtual bool isAliased(const MachineFrameInfo *) const;
85 
86  /// Return true if the memory pointed to by this PseudoSourceValue can ever
87  /// alias an LLVM IR Value.
88  virtual bool mayAlias(const MachineFrameInfo *) const;
89 };
90 
91 /// A specialized PseudoSourceValue for holding FixedStack values, which must
92 /// include a frame index.
94  const int FI;
95 
96 public:
98  : PseudoSourceValue(FixedStack, TII), FI(FI) {}
99 
100  static bool classof(const PseudoSourceValue *V) {
101  return V->kind() == FixedStack;
102  }
103 
104  bool isConstant(const MachineFrameInfo *MFI) const override;
105 
106  bool isAliased(const MachineFrameInfo *MFI) const override;
107 
108  bool mayAlias(const MachineFrameInfo *) const override;
109 
110  void printCustom(raw_ostream &OS) const override;
111 
112  int getFrameIndex() const { return FI; }
113 };
114 
116 protected:
117  CallEntryPseudoSourceValue(unsigned Kind, const TargetInstrInfo &TII);
118 
119 public:
120  bool isConstant(const MachineFrameInfo *) const override;
121  bool isAliased(const MachineFrameInfo *) const override;
122  bool mayAlias(const MachineFrameInfo *) const override;
123 };
124 
125 /// A specialized pseudo source value for holding GlobalValue values.
127  const GlobalValue *GV;
128 
129 public:
131  const TargetInstrInfo &TII);
132 
133  static bool classof(const PseudoSourceValue *V) {
134  return V->kind() == GlobalValueCallEntry;
135  }
136 
137  const GlobalValue *getValue() const { return GV; }
138 };
139 
140 /// A specialized pseudo source value for holding external symbol values.
142  const char *ES;
143 
144 public:
145  ExternalSymbolPseudoSourceValue(const char *ES, const TargetInstrInfo &TII);
146 
147  static bool classof(const PseudoSourceValue *V) {
148  return V->kind() == ExternalSymbolCallEntry;
149  }
150 
151  const char *getSymbol() const { return ES; }
152 };
153 
154 /// Manages creation of pseudo source values.
156  const TargetInstrInfo &TII;
157  const PseudoSourceValue StackPSV, GOTPSV, JumpTablePSV, ConstantPoolPSV;
158  std::map<int, std::unique_ptr<FixedStackPseudoSourceValue>> FSValues;
160  ExternalCallEntries;
161  ValueMap<const GlobalValue *,
162  std::unique_ptr<const GlobalValuePseudoSourceValue>>
163  GlobalCallEntries;
164 
165 public:
167 
168  /// Return a pseudo source value referencing the area below the stack frame of
169  /// a function, e.g., the argument space.
170  const PseudoSourceValue *getStack();
171 
172  /// Return a pseudo source value referencing the global offset table
173  /// (or something the like).
174  const PseudoSourceValue *getGOT();
175 
176  /// Return a pseudo source value referencing the constant pool. Since constant
177  /// pools are constant, this doesn't need to identify a specific constant
178  /// pool entry.
179  const PseudoSourceValue *getConstantPool();
180 
181  /// Return a pseudo source value referencing a jump table. Since jump tables
182  /// are constant, this doesn't need to identify a specific jump table.
183  const PseudoSourceValue *getJumpTable();
184 
185  /// Return a pseudo source value referencing a fixed stack frame entry,
186  /// e.g., a spill slot.
187  const PseudoSourceValue *getFixedStack(int FI);
188 
189  const PseudoSourceValue *getGlobalValueCallEntry(const GlobalValue *GV);
190 
191  const PseudoSourceValue *getExternalSymbolCallEntry(const char *ES);
192 };
193 
194 } // end namespace llvm
195 
196 #endif
This class represents lattice values for constants.
Definition: AllocatorList.h:23
virtual bool mayAlias(const MachineFrameInfo *) const
Return true if the memory pointed to by this PseudoSourceValue can ever alias an LLVM IR Value...
virtual bool isAliased(const MachineFrameInfo *) const
Test whether the memory pointed to by this PseudoSourceValue may also be pointed to by an LLVM IR Val...
virtual bool isConstant(const MachineFrameInfo *) const
Test whether the memory pointed to by this PseudoSourceValue has a constant value.
A description of a memory reference used in the backend.
const HexagonInstrInfo * TII
The MachineFrameInfo class represents an abstract stack frame until prolog/epilog code is inserted...
unsigned getTargetCustom() const
TargetInstrInfo - Interface to description of machine instruction set.
unsigned getAddressSpace() const
static bool classof(const PseudoSourceValue *V)
FixedStackPseudoSourceValue(int FI, const TargetInstrInfo &TII)
See the file comment.
Definition: ValueMap.h:85
AddressSpace
Definition: NVPTXBaseInfo.h:21
StringMap - This is an unconventional map that is specialized for handling keys that are "strings"...
Definition: StringMap.h:219
A specialized pseudo source value for holding external symbol values.
Special value supplied for machine level alias analysis.
A specialized pseudo source value for holding GlobalValue values.
static bool classof(const PseudoSourceValue *V)
const GlobalValue * getValue() const
static bool classof(const PseudoSourceValue *V)
PseudoSourceValue(unsigned Kind, const TargetInstrInfo &TII)
raw_ostream & operator<<(raw_ostream &OS, const APInt &I)
Definition: APInt.h:2047
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:45
Manages creation of pseudo source values.
A specialized PseudoSourceValue for holding FixedStack values, which must include a frame index...
AddressSpace
An integer that identifies all of the supported AVR address spaces.
Definition: AVR.h:40