1 //===-- llvm/CodeGen/PseudoSourceValue.h ------------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the declaration of the PseudoSourceValue class.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CODEGEN_PSEUDOSOURCEVALUE_H
15 #define LLVM_CODEGEN_PSEUDOSOURCEVALUE_H
17 #include "llvm/IR/Value.h"
20 class MachineFrameInfo;
21 class MachineMemOperand;
24 /// PseudoSourceValue - Special value supplied for machine level alias
25 /// analysis. It indicates that a memory access references the functions
26 /// stack frame (e.g., a spill slot), below the stack frame (e.g., argument
27 /// space), or constant pool.
28 class PseudoSourceValue {
30 friend raw_ostream &llvm::operator<<(raw_ostream &OS,
31 const MachineMemOperand &MMO);
33 /// printCustom - Implement printing for PseudoSourceValue. This is called
34 /// from Value::print or Value's operator<<.
36 virtual void printCustom(raw_ostream &O) const;
39 /// isFixed - Whether this is a FixedStackPseudoSourceValue.
42 explicit PseudoSourceValue(bool isFixed = false);
44 virtual ~PseudoSourceValue();
46 /// isConstant - Test whether the memory pointed to by this
47 /// PseudoSourceValue has a constant value.
49 virtual bool isConstant(const MachineFrameInfo *) const;
51 /// isAliased - Test whether the memory pointed to by this
52 /// PseudoSourceValue may also be pointed to by an LLVM IR Value.
53 virtual bool isAliased(const MachineFrameInfo *) const;
55 /// mayAlias - Return true if the memory pointed to by this
56 /// PseudoSourceValue can ever alias an LLVM IR Value.
57 virtual bool mayAlias(const MachineFrameInfo *) const;
59 /// A pseudo source value referencing a fixed stack frame entry,
60 /// e.g., a spill slot.
61 static const PseudoSourceValue *getFixedStack(int FI);
63 /// A pseudo source value referencing the area below the stack frame of
64 /// a function, e.g., the argument space.
65 static const PseudoSourceValue *getStack();
67 /// A pseudo source value referencing the global offset table
68 /// (or something the like).
69 static const PseudoSourceValue *getGOT();
71 /// A pseudo source value referencing the constant pool. Since constant
72 /// pools are constant, this doesn't need to identify a specific constant
74 static const PseudoSourceValue *getConstantPool();
76 /// A pseudo source value referencing a jump table. Since jump tables are
77 /// constant, this doesn't need to identify a specific jump table.
78 static const PseudoSourceValue *getJumpTable();
81 /// FixedStackPseudoSourceValue - A specialized PseudoSourceValue
82 /// for holding FixedStack values, which must include a frame
84 class FixedStackPseudoSourceValue : public PseudoSourceValue {
87 explicit FixedStackPseudoSourceValue(int fi) :
88 PseudoSourceValue(true), FI(fi) {}
90 /// classof - Methods for support type inquiry through isa, cast, and
93 static inline bool classof(const PseudoSourceValue *V) {
94 return V->isFixed == true;
97 bool isConstant(const MachineFrameInfo *MFI) const override;
99 bool isAliased(const MachineFrameInfo *MFI) const override;
101 bool mayAlias(const MachineFrameInfo *) const override;
103 void printCustom(raw_ostream &OS) const override;
105 int getFrameIndex() const { return FI; }
107 } // End llvm namespace