X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FInstruction.h;h=189c34a50218463ca70cf09e9cabc3c6a8df2e60;hb=edf8e48c216a10d1b867aba0308842116f83547b;hp=a5df1547405884e09f876fe853471bebb30a6dd7;hpb=631a19d89455e542295abb509493fc1581a10099;p=oota-llvm.git diff --git a/include/llvm/Instruction.h b/include/llvm/Instruction.h index a5df1547405..189c34a5021 100644 --- a/include/llvm/Instruction.h +++ b/include/llvm/Instruction.h @@ -2,8 +2,8 @@ // // The LLVM Compiler Infrastructure // -// This file was developed by the LLVM research group and is distributed under -// the University of Illinois Open Source License. See LICENSE.TXT for details. +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // @@ -16,76 +16,76 @@ #define LLVM_INSTRUCTION_H #include "llvm/User.h" +#include "llvm/ADT/ilist_node.h" namespace llvm { -struct AssemblyAnnotationWriter; -class BinaryOperator; +class LLVMContext; -template struct ilist_traits; -template class SymbolTableListTraits; +template + class SymbolTableListTraits; -class Instruction : public User { +class Instruction : public User, public ilist_node { void operator=(const Instruction &); // Do not implement Instruction(const Instruction &); // Do not implement BasicBlock *Parent; - Instruction *Prev, *Next; // Next and Prev links for our intrusive linked list - void setNext(Instruction *N) { Next = N; } - void setPrev(Instruction *N) { Prev = N; } - - friend class SymbolTableListTraits >; + friend class SymbolTableListTraits; void setParent(BasicBlock *P); - -private: - // FIXME: This is a dirty hack. Setcc instructions shouldn't encode the CC - // into the opcode field. When they don't, this will be unneeded. - void setOpcode(unsigned NewOpcode); - friend class BinaryOperator; protected: Instruction(const Type *Ty, unsigned iType, Use *Ops, unsigned NumOps, - const std::string &Name = "", Instruction *InsertBefore = 0); Instruction(const Type *Ty, unsigned iType, Use *Ops, unsigned NumOps, - const std::string &Name, BasicBlock *InsertAtEnd); + BasicBlock *InsertAtEnd); public: - - ~Instruction() { - assert(Parent == 0 && "Instruction still linked in the program!"); - } - - /// mayWriteToMemory - Return true if this instruction may modify memory. - /// - virtual bool mayWriteToMemory() const { return false; } - + // Out of line virtual method, so the vtable, etc has a home. + ~Instruction(); + /// clone() - Create a copy of 'this' instruction that is identical in all /// ways except the following: /// * The instruction has no parent /// * The instruction has no name /// - virtual Instruction *clone() const = 0; + virtual Instruction *clone(LLVMContext &Context) const = 0; /// isIdenticalTo - Return true if the specified instruction is exactly /// identical to the current one. This means that all operands match and any /// extra information (e.g. load is volatile) agree. - bool isIdenticalTo(Instruction *I) const; - - + bool isIdenticalTo(const Instruction *I) const; + + /// isIdenticalToWhenDefined - This is like isIdenticalTo, except that it + /// ignores the SubclassOptionalData flags, which specify conditions + /// under which the instruction's result is undefined. + bool isIdenticalToWhenDefined(const Instruction *I) const; + + /// This function determines if the specified instruction executes the same + /// operation as the current one. This means that the opcodes, type, operand + /// types and any other factors affecting the operation must be the same. This + /// is similar to isIdenticalTo except the operands themselves don't have to + /// be identical. + /// @returns true if the specified instruction is the same operation as + /// the current one. + /// @brief Determine if one instruction is the same operation as another. + bool isSameOperationAs(const Instruction *I) const; + + /// isUsedOutsideOfBlock - Return true if there are any uses of this + /// instruction in blocks other than the specified block. Note that PHI nodes + /// are considered to evaluate their operands in the corresponding predecessor + /// block. + bool isUsedOutsideOfBlock(const BasicBlock *BB) const; + + + /// use_back - Specialize the methods defined in Value, as we know that an + /// instruction can only be used by other instructions. + Instruction *use_back() { return cast(*use_begin());} + const Instruction *use_back() const { return cast(*use_begin());} + // Accessor methods... // inline const BasicBlock *getParent() const { return Parent; } inline BasicBlock *getParent() { return Parent; } - // getNext/Prev - Return the next or previous instruction in the list. The - // last node in the list is a terminator instruction. - Instruction *getNext() { return Next; } - const Instruction *getNext() const { return Next; } - Instruction *getPrev() { return Prev; } - const Instruction *getPrev() const { return Prev; } - /// removeFromParent - This method unlinks 'this' from the containing basic /// block, but does not delete it. /// @@ -96,6 +96,14 @@ public: /// void eraseFromParent(); + /// insertBefore - Insert an unlinked instructions into a basic block + /// immediately before the specified instruction. + void insertBefore(Instruction *InsertPos); + + /// insertAfter - Insert an unlinked instructions into a basic block + /// immediately after the specified instruction. + void insertAfter(Instruction *InsertPos); + /// moveBefore - Unlink this instruction from its current basic block and /// insert it into the basic block that MovePos lives in, right before /// MovePos. @@ -105,22 +113,44 @@ public: /// Subclass classification... getOpcode() returns a member of /// one of the enums that is coming soon (down below)... /// - unsigned getOpcode() const { return getValueType() - InstructionVal; } - const char *getOpcodeName() const { - return getOpcodeName(getOpcode()); - } + unsigned getOpcode() const { return getValueID() - InstructionVal; } + const char *getOpcodeName() const { return getOpcodeName(getOpcode()); } + bool isTerminator() const { return isTerminator(getOpcode()); } + bool isBinaryOp() const { return isBinaryOp(getOpcode()); } + bool isShift() { return isShift(getOpcode()); } + bool isCast() const { return isCast(getOpcode()); } + + + static const char* getOpcodeName(unsigned OpCode); static inline bool isTerminator(unsigned OpCode) { return OpCode >= TermOpsBegin && OpCode < TermOpsEnd; } - inline bool isTerminator() const { // Instance of TerminatorInst? - return isTerminator(getOpcode()); + static inline bool isBinaryOp(unsigned Opcode) { + return Opcode >= BinaryOpsBegin && Opcode < BinaryOpsEnd; + } + + /// @brief Determine if the Opcode is one of the shift instructions. + static inline bool isShift(unsigned Opcode) { + return Opcode >= Shl && Opcode <= AShr; } - inline bool isBinaryOp() const { - return getOpcode() >= BinaryOpsBegin && getOpcode() < BinaryOpsEnd; + /// isLogicalShift - Return true if this is a logical shift left or a logical + /// shift right. + inline bool isLogicalShift() const { + return getOpcode() == Shl || getOpcode() == LShr; + } + + /// isArithmeticShift - Return true if this is an arithmetic shift right. + inline bool isArithmeticShift() const { + return getOpcode() == AShr; + } + + /// @brief Determine if the OpCode is one of the CastInst instructions. + static inline bool isCast(unsigned OpCode) { + return OpCode >= CastOpsBegin && OpCode < CastOpsEnd; } /// isAssociative - Return true if the instruction is associative: @@ -143,26 +173,52 @@ public: bool isCommutative() const { return isCommutative(getOpcode()); } static bool isCommutative(unsigned op); - /// isRelational - Return true if the instruction is a Set* instruction: + /// mayWriteToMemory - Return true if this instruction may modify memory. + /// + bool mayWriteToMemory() const; + + /// mayReadFromMemory - Return true if this instruction may read memory. /// - bool isRelational() const { return isRelational(getOpcode()); } - static bool isRelational(unsigned op); + bool mayReadFromMemory() const; + /// mayThrow - Return true if this instruction may throw an exception. + /// + bool mayThrow() const; - /// isTrappingInstruction - Return true if the instruction may trap. + /// mayHaveSideEffects - Return true if the instruction may have side effects. /// - bool isTrapping() const { - return isTrapping(getOpcode()); + /// Note that this does not consider malloc and alloca to have side + /// effects because the newly allocated memory is completely invisible to + /// instructions which don't used the returned value. For cases where this + /// matters, isSafeToSpeculativelyExecute may be more appropriate. + bool mayHaveSideEffects() const { + return mayWriteToMemory() || mayThrow(); } - static bool isTrapping(unsigned op); - virtual void print(std::ostream &OS) const { print(OS, 0); } - void print(std::ostream &OS, AssemblyAnnotationWriter *AAW) const; + /// isSafeToSpeculativelyExecute - Return true if the instruction does not + /// have any effects besides calculating the result and does not have + /// undefined behavior. + /// + /// This method never returns true for an instruction that returns true for + /// mayHaveSideEffects; however, this method also does some other checks in + /// addition. It checks for undefined behavior, like dividing by zero or + /// loading from an invalid pointer (but not for undefined results, like a + /// shift with a shift amount larger than the width of the result). It checks + /// for malloc and alloca because speculatively executing them might cause a + /// memory leak. It also returns false for instructions related to control + /// flow, specifically terminators and PHI nodes. + /// + /// This method only looks at the instruction itself and its operands, so if + /// this method returns true, it is safe to move the instruction as long as + /// the correct dominance relationships for the operands and users hold. + /// However, this method can return true for instructions that read memory; + /// for such instructions, moving them may change the resulting value. + bool isSafeToSpeculativelyExecute() const; /// Methods for support type inquiry through isa, cast, and dyn_cast: static inline bool classof(const Instruction *) { return true; } static inline bool classof(const Value *V) { - return V->getValueType() >= Value::InstructionVal; + return V->getValueID() >= Value::InstructionVal; } //---------------------------------------------------------------------- @@ -189,6 +245,13 @@ public: #include "llvm/Instruction.def" }; + enum CastOps { +#define FIRST_CAST_INST(N) CastOpsBegin = N, +#define HANDLE_CAST_INST(N, OPC, CLASS) OPC = N, +#define LAST_CAST_INST(N) CastOpsEnd = N+1 +#include "llvm/Instruction.def" + }; + enum OtherOps { #define FIRST_OTHER_INST(N) OtherOpsBegin = N, #define HANDLE_OTHER_INST(N, OPC, CLASS) OPC = N, @@ -197,6 +260,18 @@ public: }; }; +// Instruction* is only 4-byte aligned. +template<> +class PointerLikeTypeTraits { + typedef Instruction* PT; +public: + static inline void *getAsVoidPointer(PT P) { return P; } + static inline PT getFromVoidPointer(void *P) { + return static_cast(P); + } + enum { NumLowBitsAvailable = 2 }; +}; + } // End llvm namespace #endif