1 //===-- llvm/Instruction.h - Instruction class definition -------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the declaration of the Instruction class, which is the
11 // base class for all of the LLVM instructions.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_INSTRUCTION_H
16 #define LLVM_INSTRUCTION_H
18 #include "llvm/User.h"
22 struct AssemblyAnnotationWriter;
25 template<typename SC> struct ilist_traits;
26 template<typename ValueSubClass, typename ItemParentClass, typename SymTabClass,
27 typename SubClass> class SymbolTableListTraits;
29 class Instruction : public User {
30 void operator=(const Instruction &); // Do not implement
31 Instruction(const Instruction &); // Do not implement
34 Instruction *Prev, *Next; // Next and Prev links for our intrusive linked list
36 void setNext(Instruction *N) { Next = N; }
37 void setPrev(Instruction *N) { Prev = N; }
39 friend class SymbolTableListTraits<Instruction, BasicBlock, Function,
40 ilist_traits<Instruction> >;
41 void setParent(BasicBlock *P);
43 Instruction(const Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
44 const std::string &Name = "",
45 Instruction *InsertBefore = 0);
46 Instruction(const Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
47 const std::string &Name, BasicBlock *InsertAtEnd);
49 // Out of line virtual method, so the vtable, etc has a home.
52 /// mayWriteToMemory - Return true if this instruction may modify memory.
54 virtual bool mayWriteToMemory() const { return false; }
56 /// clone() - Create a copy of 'this' instruction that is identical in all
57 /// ways except the following:
58 /// * The instruction has no parent
59 /// * The instruction has no name
61 virtual Instruction *clone() const = 0;
63 /// isIdenticalTo - Return true if the specified instruction is exactly
64 /// identical to the current one. This means that all operands match and any
65 /// extra information (e.g. load is volatile) agree.
66 bool isIdenticalTo(Instruction *I) const;
68 /// This function determines if the specified instruction executes the same
69 /// operation as the current one. This means that the opcodes, type, operand
70 /// types and any other factors affecting the operation must be the same. This
71 /// is similar to isIdenticalTo except the operands themselves don't have to
73 /// @returns true if the specified instruction is the same operation as
75 /// @brief Determine if one instruction is the same operation as another.
76 bool isSameOperationAs(Instruction *I) const;
78 /// use_back - Specialize the methods defined in Value, as we know that an
79 /// instruction can only be used by other instructions.
80 Instruction *use_back() { return cast<Instruction>(*use_begin());}
81 const Instruction *use_back() const { return cast<Instruction>(*use_begin());}
83 // Accessor methods...
85 inline const BasicBlock *getParent() const { return Parent; }
86 inline BasicBlock *getParent() { return Parent; }
88 // getNext/Prev - Return the next or previous instruction in the list. The
89 // last node in the list is a terminator instruction.
90 Instruction *getNext() { return Next; }
91 const Instruction *getNext() const { return Next; }
92 Instruction *getPrev() { return Prev; }
93 const Instruction *getPrev() const { return Prev; }
95 /// removeFromParent - This method unlinks 'this' from the containing basic
96 /// block, but does not delete it.
98 void removeFromParent();
100 /// eraseFromParent - This method unlinks 'this' from the containing basic
101 /// block and deletes it.
103 void eraseFromParent();
105 /// moveBefore - Unlink this instruction from its current basic block and
106 /// insert it into the basic block that MovePos lives in, right before
108 void moveBefore(Instruction *MovePos);
110 // ---------------------------------------------------------------------------
111 /// Subclass classification... getOpcode() returns a member of
112 /// one of the enums that is coming soon (down below)...
114 unsigned getOpcode() const { return getValueType() - InstructionVal; }
115 const char *getOpcodeName() const {
116 return getOpcodeName(getOpcode());
118 static const char* getOpcodeName(unsigned OpCode);
120 static inline bool isTerminator(unsigned OpCode) {
121 return OpCode >= TermOpsBegin && OpCode < TermOpsEnd;
124 inline bool isTerminator() const { // Instance of TerminatorInst?
125 return isTerminator(getOpcode());
128 inline bool isBinaryOp() const {
129 return getOpcode() >= BinaryOpsBegin && getOpcode() < BinaryOpsEnd;
132 /// @brief Determine if the Opcode is one of the shift instructions.
133 static inline bool isShift(unsigned Opcode) {
134 return Opcode >= Shl && Opcode <= AShr;
137 /// @brief Determine if the instruction's opcode is one of the shift
139 inline bool isShift() { return isShift(getOpcode()); }
141 /// isLogicalShift - Return true if this is a logical shift left or a logical
143 inline bool isLogicalShift() {
144 return getOpcode() == Shl || getOpcode() == LShr;
147 /// isLogicalShift - Return true if this is a logical shift left or a logical
149 inline bool isArithmeticShift() {
150 return getOpcode() == AShr;
153 /// @brief Determine if the OpCode is one of the CastInst instructions.
154 static inline bool isCast(unsigned OpCode) {
155 return OpCode >= CastOpsBegin && OpCode < CastOpsEnd;
158 /// @brief Determine if this is one of the CastInst instructions.
159 inline bool isCast() const {
160 return isCast(getOpcode());
163 /// isAssociative - Return true if the instruction is associative:
165 /// Associative operators satisfy: x op (y op z) === (x op y) op z
167 /// In LLVM, the Add, Mul, And, Or, and Xor operators are associative, when
168 /// not applied to floating point types.
170 bool isAssociative() const { return isAssociative(getOpcode(), getType()); }
171 static bool isAssociative(unsigned op, const Type *Ty);
173 /// isCommutative - Return true if the instruction is commutative:
175 /// Commutative operators satisfy: (x op y) === (y op x)
177 /// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
178 /// applied to any type.
180 bool isCommutative() const { return isCommutative(getOpcode()); }
181 static bool isCommutative(unsigned op);
183 /// isTrappingInstruction - Return true if the instruction may trap.
185 bool isTrapping() const {
186 return isTrapping(getOpcode());
188 static bool isTrapping(unsigned op);
190 virtual void print(std::ostream &OS) const { print(OS, 0); }
191 void print(std::ostream *OS) const { if (OS) print(*OS); }
192 void print(std::ostream &OS, AssemblyAnnotationWriter *AAW) const;
194 /// Methods for support type inquiry through isa, cast, and dyn_cast:
195 static inline bool classof(const Instruction *) { return true; }
196 static inline bool classof(const Value *V) {
197 return V->getValueType() >= Value::InstructionVal;
200 //----------------------------------------------------------------------
201 // Exported enumerations...
203 enum TermOps { // These terminate basic blocks
204 #define FIRST_TERM_INST(N) TermOpsBegin = N,
205 #define HANDLE_TERM_INST(N, OPC, CLASS) OPC = N,
206 #define LAST_TERM_INST(N) TermOpsEnd = N+1
207 #include "llvm/Instruction.def"
211 #define FIRST_BINARY_INST(N) BinaryOpsBegin = N,
212 #define HANDLE_BINARY_INST(N, OPC, CLASS) OPC = N,
213 #define LAST_BINARY_INST(N) BinaryOpsEnd = N+1
214 #include "llvm/Instruction.def"
218 #define FIRST_MEMORY_INST(N) MemoryOpsBegin = N,
219 #define HANDLE_MEMORY_INST(N, OPC, CLASS) OPC = N,
220 #define LAST_MEMORY_INST(N) MemoryOpsEnd = N+1
221 #include "llvm/Instruction.def"
225 #define FIRST_CAST_INST(N) CastOpsBegin = N,
226 #define HANDLE_CAST_INST(N, OPC, CLASS) OPC = N,
227 #define LAST_CAST_INST(N) CastOpsEnd = N+1
228 #include "llvm/Instruction.def"
232 #define FIRST_OTHER_INST(N) OtherOpsBegin = N,
233 #define HANDLE_OTHER_INST(N, OPC, CLASS) OPC = N,
234 #define LAST_OTHER_INST(N) OtherOpsEnd = N+1
235 #include "llvm/Instruction.def"
239 } // End llvm namespace