llvm-mirror/include/llvm/Instruction.h
Owen Anderson 79605db969 Add an insertBefore method for attaching previously unattached instructions,
such as those created by clone(), to a basic block.

llvm-svn: 52424
2008-06-17 18:29:27 +00:00

246 lines
8.8 KiB
C++

//===-- llvm/Instruction.h - Instruction class definition -------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the declaration of the Instruction class, which is the
// base class for all of the LLVM instructions.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_INSTRUCTION_H
#define LLVM_INSTRUCTION_H
#include "llvm/User.h"
namespace llvm {
struct AssemblyAnnotationWriter;
template<typename ValueSubClass, typename ItemParentClass>
class SymbolTableListTraits;
class Instruction : public User {
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<Instruction, BasicBlock>;
void setParent(BasicBlock *P);
protected:
Instruction(const Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
Instruction *InsertBefore = 0);
Instruction(const Type *Ty, unsigned iType, Use *Ops, unsigned NumOps,
BasicBlock *InsertAtEnd);
public:
// Out of line virtual method, so the vtable, etc has a home.
~Instruction();
/// mayWriteToMemory - Return true if this instruction may modify memory.
///
bool mayWriteToMemory() const;
/// mayReadFromMemory - Return true if this instruction may read memory.
///
bool mayReadFromMemory() const;
/// 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;
/// 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;
/// 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(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<Instruction>(*use_begin());}
const Instruction *use_back() const { return cast<Instruction>(*use_begin());}
// Accessor methods...
//
inline const BasicBlock *getParent() const { return Parent; }
inline BasicBlock *getParent() { return Parent; }
/// removeFromParent - This method unlinks 'this' from the containing basic
/// block, but does not delete it.
///
void removeFromParent();
/// eraseFromParent - This method unlinks 'this' from the containing basic
/// block and deletes it.
///
void eraseFromParent();
/// insertBefore - Insert an unlinked instructions into a basic block
/// immediately before the specified instruction.
void insertBefore(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.
void moveBefore(Instruction *MovePos);
// ---------------------------------------------------------------------------
/// Subclass classification... getOpcode() returns a member of
/// one of the enums that is coming soon (down below)...
///
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;
}
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;
}
/// isLogicalShift - Return true if this is a logical shift left or a logical
/// shift right.
inline bool isLogicalShift() const {
return getOpcode() == Shl || getOpcode() == LShr;
}
/// isLogicalShift - Return true if this is a logical shift left or a logical
/// 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:
///
/// Associative operators satisfy: x op (y op z) === (x op y) op z
///
/// In LLVM, the Add, Mul, And, Or, and Xor operators are associative, when
/// not applied to floating point types.
///
bool isAssociative() const { return isAssociative(getOpcode(), getType()); }
static bool isAssociative(unsigned op, const Type *Ty);
/// isCommutative - Return true if the instruction is commutative:
///
/// Commutative operators satisfy: (x op y) === (y op x)
///
/// In LLVM, these are the associative operators, plus SetEQ and SetNE, when
/// applied to any type.
///
bool isCommutative() const { return isCommutative(getOpcode()); }
static bool isCommutative(unsigned op);
/// isTrappingInstruction - Return true if the instruction may trap.
///
bool isTrapping() const {
return isTrapping(getOpcode());
}
static bool isTrapping(unsigned op);
virtual void print(std::ostream &OS) const { print(OS, 0); }
void print(std::ostream *OS) const { if (OS) print(*OS); }
void print(std::ostream &OS, AssemblyAnnotationWriter *AAW) 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->getValueID() >= Value::InstructionVal;
}
//----------------------------------------------------------------------
// Exported enumerations...
//
enum TermOps { // These terminate basic blocks
#define FIRST_TERM_INST(N) TermOpsBegin = N,
#define HANDLE_TERM_INST(N, OPC, CLASS) OPC = N,
#define LAST_TERM_INST(N) TermOpsEnd = N+1
#include "llvm/Instruction.def"
};
enum BinaryOps {
#define FIRST_BINARY_INST(N) BinaryOpsBegin = N,
#define HANDLE_BINARY_INST(N, OPC, CLASS) OPC = N,
#define LAST_BINARY_INST(N) BinaryOpsEnd = N+1
#include "llvm/Instruction.def"
};
enum MemoryOps {
#define FIRST_MEMORY_INST(N) MemoryOpsBegin = N,
#define HANDLE_MEMORY_INST(N, OPC, CLASS) OPC = N,
#define LAST_MEMORY_INST(N) MemoryOpsEnd = N+1
#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,
#define LAST_OTHER_INST(N) OtherOpsEnd = N+1
#include "llvm/Instruction.def"
};
private:
// 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; }
};
} // End llvm namespace
#endif