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Instruction.h

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00001 //===-- llvm/Instruction.h - Instruction class definition -------*- C++ -*-===//
00002 // 
00003 //                     The LLVM Compiler Infrastructure
00004 //
00005 // This file was developed by the LLVM research group and is distributed under
00006 // the University of Illinois Open Source License. See LICENSE.TXT for details.
00007 // 
00008 //===----------------------------------------------------------------------===//
00009 //
00010 // This file contains the declaration of the Instruction class, which is the
00011 // base class for all of the LLVM instructions.
00012 //
00013 //===----------------------------------------------------------------------===//
00014 
00015 #ifndef LLVM_INSTRUCTION_H
00016 #define LLVM_INSTRUCTION_H
00017 
00018 #include "llvm/User.h"
00019 
00020 namespace llvm {
00021 
00022 struct AssemblyAnnotationWriter;
00023 class BinaryOperator;
00024 
00025 template<typename SC> struct ilist_traits;
00026 template<typename ValueSubClass, typename ItemParentClass, typename SymTabClass,
00027          typename SubClass> class SymbolTableListTraits;
00028 
00029 class Instruction : public User {
00030   BasicBlock *Parent;
00031   Instruction *Prev, *Next; // Next and Prev links for our intrusive linked list
00032 
00033   void setNext(Instruction *N) { Next = N; }
00034   void setPrev(Instruction *N) { Prev = N; }
00035 
00036   friend class SymbolTableListTraits<Instruction, BasicBlock, Function,
00037                                      ilist_traits<Instruction> >;
00038   void setParent(BasicBlock *P);
00039   void init();
00040 
00041 private:
00042   // FIXME: This is a dirty hack.  Setcc instructions shouldn't encode the CC
00043   // into the opcode field.  When they don't, this will be unneeded.
00044   void setOpcode(unsigned NewOpcode);
00045   friend class BinaryOperator;
00046 protected:
00047   Instruction(const Type *Ty, unsigned iType, const std::string &Name = "",
00048               Instruction *InsertBefore = 0);
00049   Instruction(const Type *Ty, unsigned iType, const std::string &Name,
00050               BasicBlock *InsertAtEnd);
00051 public:
00052 
00053   ~Instruction() {
00054     assert(Parent == 0 && "Instruction still linked in the program!");
00055   }
00056 
00057   // Specialize setName to handle symbol table majik...
00058   virtual void setName(const std::string &name, SymbolTable *ST = 0);
00059   
00060   /// mayWriteToMemory - Return true if this instruction may modify memory.
00061   ///
00062   virtual bool mayWriteToMemory() const { return false; }
00063 
00064   /// clone() - Create a copy of 'this' instruction that is identical in all
00065   /// ways except the following:
00066   ///   * The instruction has no parent
00067   ///   * The instruction has no name
00068   ///
00069   virtual Instruction *clone() const = 0;
00070 
00071   /// isIdenticalTo - Return true if the specified instruction is exactly
00072   /// identical to the current one.  This means that all operands match and any
00073   /// extra information (e.g. load is volatile) agree.
00074   bool isIdenticalTo(Instruction *I) const;
00075 
00076   
00077   // Accessor methods...
00078   //
00079   inline const BasicBlock *getParent() const { return Parent; }
00080   inline       BasicBlock *getParent()       { return Parent; }
00081 
00082   // getNext/Prev - Return the next or previous instruction in the list.  The
00083   // last node in the list is a terminator instruction.
00084         Instruction *getNext()       { return Next; }
00085   const Instruction *getNext() const { return Next; }
00086         Instruction *getPrev()       { return Prev; }
00087   const Instruction *getPrev() const { return Prev; }
00088 
00089   /// removeFromParent - This method unlinks 'this' from the containing basic
00090   /// block, but does not delete it.
00091   ///
00092   void removeFromParent();
00093 
00094   /// eraseFromParent - This method unlinks 'this' from the containing basic
00095   /// block and deletes it.
00096   ///
00097   void eraseFromParent();
00098 
00099   // ---------------------------------------------------------------------------
00100   /// Subclass classification... getOpcode() returns a member of 
00101   /// one of the enums that is coming soon (down below)...
00102   ///
00103   unsigned getOpcode() const { return getValueType() - InstructionVal; }
00104   virtual const char *getOpcodeName() const {
00105     return getOpcodeName(getOpcode());
00106   }
00107   static const char* getOpcodeName(unsigned OpCode);
00108 
00109   static inline bool isTerminator(unsigned OpCode) {
00110     return OpCode >= TermOpsBegin && OpCode < TermOpsEnd;
00111   }
00112 
00113   inline bool isTerminator() const {   // Instance of TerminatorInst?
00114     return isTerminator(getOpcode());
00115   }
00116 
00117   inline bool isBinaryOp() const {
00118     return getOpcode() >= BinaryOpsBegin && getOpcode() < BinaryOpsEnd;
00119   }
00120 
00121   /// isAssociative - Return true if the instruction is associative:
00122   ///
00123   ///   Associative operators satisfy:  x op (y op z) === (x op y) op z
00124   ///
00125   /// In LLVM, the Add, Mul, And, Or, and Xor operators are associative, when
00126   /// not applied to floating point types.
00127   ///
00128   bool isAssociative() const { return isAssociative(getOpcode(), getType()); }
00129   static bool isAssociative(unsigned op, const Type *Ty);
00130 
00131   /// isCommutative - Return true if the instruction is commutative:
00132   ///
00133   ///   Commutative operators satisfy: (x op y) === (y op x)
00134   ///
00135   /// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
00136   /// applied to any type.
00137   ///
00138   bool isCommutative() const { return isCommutative(getOpcode()); }
00139   static bool isCommutative(unsigned op);
00140 
00141   /// isRelational - Return true if the instruction is a Set* instruction:
00142   ///
00143   bool isRelational() const { return isRelational(getOpcode()); }
00144   static bool isRelational(unsigned op);
00145 
00146 
00147   /// isTrappingInstruction - Return true if the instruction may trap.
00148   ///
00149   bool isTrapping() const {
00150     return isTrapping(getOpcode()); 
00151   }
00152   static bool isTrapping(unsigned op);
00153   
00154   virtual void print(std::ostream &OS) const { print(OS, 0); }
00155   void print(std::ostream &OS, AssemblyAnnotationWriter *AAW) const;
00156 
00157   /// Methods for support type inquiry through isa, cast, and dyn_cast:
00158   static inline bool classof(const Instruction *I) { return true; }
00159   static inline bool classof(const Value *V) {
00160     return V->getValueType() >= Value::InstructionVal;
00161   }
00162   
00163   //----------------------------------------------------------------------
00164   // Exported enumerations...
00165   //
00166   enum TermOps {       // These terminate basic blocks
00167 #define  FIRST_TERM_INST(N)             TermOpsBegin = N,
00168 #define HANDLE_TERM_INST(N, OPC, CLASS) OPC = N,
00169 #define   LAST_TERM_INST(N)             TermOpsEnd = N+1,
00170 #include "llvm/Instruction.def"
00171   };
00172 
00173   enum BinaryOps {
00174 #define  FIRST_BINARY_INST(N)             BinaryOpsBegin = N,
00175 #define HANDLE_BINARY_INST(N, OPC, CLASS) OPC = N,
00176 #define   LAST_BINARY_INST(N)             BinaryOpsEnd = N+1,
00177 #include "llvm/Instruction.def"
00178   };
00179 
00180   enum MemoryOps {
00181 #define  FIRST_MEMORY_INST(N)             MemoryOpsBegin = N,
00182 #define HANDLE_MEMORY_INST(N, OPC, CLASS) OPC = N,
00183 #define   LAST_MEMORY_INST(N)             MemoryOpsEnd = N+1,
00184 #include "llvm/Instruction.def"
00185   };
00186 
00187   enum OtherOps {
00188 #define  FIRST_OTHER_INST(N)             OtherOpsBegin = N,
00189 #define HANDLE_OTHER_INST(N, OPC, CLASS) OPC = N,
00190 #define   LAST_OTHER_INST(N)             OtherOpsEnd = N+1,
00191 #include "llvm/Instruction.def"
00192   };
00193 };
00194 
00195 } // End llvm namespace
00196 
00197 #endif