LLVM API Documentation

Instructions.h

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//===-- llvm/Instructions.h - Instruction subclass definitions --*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file exposes the class definitions of all of the subclasses of the
// Instruction class.  This is meant to be an easy way to get access to all
// instruction subclasses.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_INSTRUCTIONS_H
#define LLVM_INSTRUCTIONS_H

#include <iterator>

#include "llvm/InstrTypes.h"
#include "llvm/DerivedTypes.h"
#include "llvm/ParameterAttributes.h"
#include "llvm/BasicBlock.h"
#include "llvm/ADT/SmallVector.h"

namespace llvm {

class ConstantInt;
class PointerType;
class VectorType;
class ConstantRange;
class APInt;

//===----------------------------------------------------------------------===//
//                             AllocationInst Class
//===----------------------------------------------------------------------===//

/// AllocationInst - This class is the common base class of MallocInst and
/// AllocaInst.
///
class AllocationInst : public UnaryInstruction {
protected:
  AllocationInst(const Type *Ty, Value *ArraySize, unsigned iTy, unsigned Align,
                 const std::string &Name = "", Instruction *InsertBefore = 0);
  AllocationInst(const Type *Ty, Value *ArraySize, unsigned iTy, unsigned Align,
                 const std::string &Name, BasicBlock *InsertAtEnd);
public:
  // Out of line virtual method, so the vtable, etc. has a home.
  virtual ~AllocationInst();

  /// isArrayAllocation - Return true if there is an allocation size parameter
  /// to the allocation instruction that is not 1.
  ///
  bool isArrayAllocation() const;

  /// getArraySize - Get the number of element allocated, for a simple
  /// allocation of a single element, this will return a constant 1 value.
  ///
  const Value *getArraySize() const { return getOperand(0); }
  Value *getArraySize() { return getOperand(0); }

  /// getType - Overload to return most specific pointer type
  ///
  const PointerType *getType() const {
    return reinterpret_cast<const PointerType*>(Instruction::getType());
  }

  /// getAllocatedType - Return the type that is being allocated by the
  /// instruction.
  ///
  const Type *getAllocatedType() const;

  /// getAlignment - Return the alignment of the memory that is being allocated
  /// by the instruction.
  ///
  unsigned getAlignment() const { return (1u << SubclassData) >> 1; }
  void setAlignment(unsigned Align);

  virtual Instruction *clone() const = 0;

  // Methods for support type inquiry through isa, cast, and dyn_cast:
  static inline bool classof(const AllocationInst *) { return true; }
  static inline bool classof(const Instruction *I) {
    return I->getOpcode() == Instruction::Alloca ||
           I->getOpcode() == Instruction::Malloc;
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};


//===----------------------------------------------------------------------===//
//                                MallocInst Class
//===----------------------------------------------------------------------===//

/// MallocInst - an instruction to allocated memory on the heap
///
class MallocInst : public AllocationInst {
  MallocInst(const MallocInst &MI);
public:
  explicit MallocInst(const Type *Ty, Value *ArraySize = 0,
                      const std::string &NameStr = "",
                      Instruction *InsertBefore = 0)
    : AllocationInst(Ty, ArraySize, Malloc, 0, NameStr, InsertBefore) {}
  MallocInst(const Type *Ty, Value *ArraySize, const std::string &NameStr,
             BasicBlock *InsertAtEnd)
    : AllocationInst(Ty, ArraySize, Malloc, 0, NameStr, InsertAtEnd) {}

  MallocInst(const Type *Ty, const std::string &NameStr,
             Instruction *InsertBefore = 0)
    : AllocationInst(Ty, 0, Malloc, 0, NameStr, InsertBefore) {}
  MallocInst(const Type *Ty, const std::string &NameStr, BasicBlock *InsertAtEnd)
    : AllocationInst(Ty, 0, Malloc, 0, NameStr, InsertAtEnd) {}

  MallocInst(const Type *Ty, Value *ArraySize, unsigned Align,
             const std::string &NameStr, BasicBlock *InsertAtEnd)
    : AllocationInst(Ty, ArraySize, Malloc, Align, NameStr, InsertAtEnd) {}
  MallocInst(const Type *Ty, Value *ArraySize, unsigned Align,
                      const std::string &NameStr = "",
                      Instruction *InsertBefore = 0)
    : AllocationInst(Ty, ArraySize, Malloc, Align, NameStr, InsertBefore) {}

  virtual MallocInst *clone() const;

  // Methods for support type inquiry through isa, cast, and dyn_cast:
  static inline bool classof(const MallocInst *) { return true; }
  static inline bool classof(const Instruction *I) {
    return (I->getOpcode() == Instruction::Malloc);
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};


//===----------------------------------------------------------------------===//
//                                AllocaInst Class
//===----------------------------------------------------------------------===//

/// AllocaInst - an instruction to allocate memory on the stack
///
class AllocaInst : public AllocationInst {
  AllocaInst(const AllocaInst &);
public:
  explicit AllocaInst(const Type *Ty, Value *ArraySize = 0,
                      const std::string &NameStr = "",
                      Instruction *InsertBefore = 0)
    : AllocationInst(Ty, ArraySize, Alloca, 0, NameStr, InsertBefore) {}
  AllocaInst(const Type *Ty, Value *ArraySize, const std::string &NameStr,
             BasicBlock *InsertAtEnd)
    : AllocationInst(Ty, ArraySize, Alloca, 0, NameStr, InsertAtEnd) {}

  AllocaInst(const Type *Ty, const std::string &NameStr,
             Instruction *InsertBefore = 0)
    : AllocationInst(Ty, 0, Alloca, 0, NameStr, InsertBefore) {}
  AllocaInst(const Type *Ty, const std::string &NameStr,
             BasicBlock *InsertAtEnd)
    : AllocationInst(Ty, 0, Alloca, 0, NameStr, InsertAtEnd) {}

  AllocaInst(const Type *Ty, Value *ArraySize, unsigned Align,
             const std::string &NameStr = "", Instruction *InsertBefore = 0)
    : AllocationInst(Ty, ArraySize, Alloca, Align, NameStr, InsertBefore) {}
  AllocaInst(const Type *Ty, Value *ArraySize, unsigned Align,
             const std::string &NameStr, BasicBlock *InsertAtEnd)
    : AllocationInst(Ty, ArraySize, Alloca, Align, NameStr, InsertAtEnd) {}

  virtual AllocaInst *clone() const;

  // Methods for support type inquiry through isa, cast, and dyn_cast:
  static inline bool classof(const AllocaInst *) { return true; }
  static inline bool classof(const Instruction *I) {
    return (I->getOpcode() == Instruction::Alloca);
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};


//===----------------------------------------------------------------------===//
//                                 FreeInst Class
//===----------------------------------------------------------------------===//

/// FreeInst - an instruction to deallocate memory
///
class FreeInst : public UnaryInstruction {
  void AssertOK();
public:
  explicit FreeInst(Value *Ptr, Instruction *InsertBefore = 0);
  FreeInst(Value *Ptr, BasicBlock *InsertAfter);

  virtual FreeInst *clone() const;
  
  // Accessor methods for consistency with other memory operations
  Value *getPointerOperand() { return getOperand(0); }
  const Value *getPointerOperand() const { return getOperand(0); }

  // Methods for support type inquiry through isa, cast, and dyn_cast:
  static inline bool classof(const FreeInst *) { return true; }
  static inline bool classof(const Instruction *I) {
    return (I->getOpcode() == Instruction::Free);
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};


//===----------------------------------------------------------------------===//
//                                LoadInst Class
//===----------------------------------------------------------------------===//

/// LoadInst - an instruction for reading from memory.  This uses the
/// SubclassData field in Value to store whether or not the load is volatile.
///
class LoadInst : public UnaryInstruction {

  LoadInst(const LoadInst &LI)
    : UnaryInstruction(LI.getType(), Load, LI.getOperand(0)) {
    setVolatile(LI.isVolatile());
    setAlignment(LI.getAlignment());

#ifndef NDEBUG
    AssertOK();
#endif
  }
  void AssertOK();
public:
  LoadInst(Value *Ptr, const std::string &NameStr, Instruction *InsertBefore);
  LoadInst(Value *Ptr, const std::string &NameStr, BasicBlock *InsertAtEnd);
  LoadInst(Value *Ptr, const std::string &NameStr, bool isVolatile = false, 
           Instruction *InsertBefore = 0);
  LoadInst(Value *Ptr, const std::string &NameStr, bool isVolatile,
           unsigned Align, Instruction *InsertBefore = 0);
  LoadInst(Value *Ptr, const std::string &NameStr, bool isVolatile,
           BasicBlock *InsertAtEnd);
  LoadInst(Value *Ptr, const std::string &NameStr, bool isVolatile,
           unsigned Align, BasicBlock *InsertAtEnd);

  LoadInst(Value *Ptr, const char *NameStr, Instruction *InsertBefore);
  LoadInst(Value *Ptr, const char *NameStr, BasicBlock *InsertAtEnd);
  explicit LoadInst(Value *Ptr, const char *NameStr = 0,
                    bool isVolatile = false,  Instruction *InsertBefore = 0);
  LoadInst(Value *Ptr, const char *NameStr, bool isVolatile,
           BasicBlock *InsertAtEnd);
  
  /// isVolatile - Return true if this is a load from a volatile memory
  /// location.
  ///
  bool isVolatile() const { return SubclassData & 1; }

  /// setVolatile - Specify whether this is a volatile load or not.
  ///
  void setVolatile(bool V) { 
    SubclassData = (SubclassData & ~1) | (V ? 1 : 0); 
  }

  virtual LoadInst *clone() const;

  /// getAlignment - Return the alignment of the access that is being performed
  ///
  unsigned getAlignment() const {
    return (1 << (SubclassData>>1)) >> 1;
  }
  
  void setAlignment(unsigned Align);

  Value *getPointerOperand() { return getOperand(0); }
  const Value *getPointerOperand() const { return getOperand(0); }
  static unsigned getPointerOperandIndex() { return 0U; }

  // Methods for support type inquiry through isa, cast, and dyn_cast:
  static inline bool classof(const LoadInst *) { return true; }
  static inline bool classof(const Instruction *I) {
    return I->getOpcode() == Instruction::Load;
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};


//===----------------------------------------------------------------------===//
//                                StoreInst Class
//===----------------------------------------------------------------------===//

/// StoreInst - an instruction for storing to memory
///
class StoreInst : public Instruction {
  void *operator new(size_t, unsigned);  // DO NOT IMPLEMENT
  
  StoreInst(const StoreInst &SI) : Instruction(SI.getType(), Store,
                                               &Op<0>(), 2) {
    Op<0>() = SI.Op<0>();
    Op<1>() = SI.Op<1>();
    setVolatile(SI.isVolatile());
    setAlignment(SI.getAlignment());
    
#ifndef NDEBUG
    AssertOK();
#endif
  }
  void AssertOK();
public:
  // allocate space for exactly two operands
  void *operator new(size_t s) {
    return User::operator new(s, 2);
  }
  StoreInst(Value *Val, Value *Ptr, Instruction *InsertBefore);
  StoreInst(Value *Val, Value *Ptr, BasicBlock *InsertAtEnd);
  StoreInst(Value *Val, Value *Ptr, bool isVolatile = false,
            Instruction *InsertBefore = 0);
  StoreInst(Value *Val, Value *Ptr, bool isVolatile,
            unsigned Align, Instruction *InsertBefore = 0);
  StoreInst(Value *Val, Value *Ptr, bool isVolatile, BasicBlock *InsertAtEnd);
  StoreInst(Value *Val, Value *Ptr, bool isVolatile,
            unsigned Align, BasicBlock *InsertAtEnd);


  /// isVolatile - Return true if this is a load from a volatile memory
  /// location.
  ///
  bool isVolatile() const { return SubclassData & 1; }

  /// setVolatile - Specify whether this is a volatile load or not.
  ///
  void setVolatile(bool V) { 
    SubclassData = (SubclassData & ~1) | (V ? 1 : 0); 
  }

  /// Transparently provide more efficient getOperand methods.
  DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);

  /// getAlignment - Return the alignment of the access that is being performed
  ///
  unsigned getAlignment() const {
    return (1 << (SubclassData>>1)) >> 1;
  }
  
  void setAlignment(unsigned Align);
  
  virtual StoreInst *clone() const;

  Value *getPointerOperand() { return getOperand(1); }
  const Value *getPointerOperand() const { return getOperand(1); }
  static unsigned getPointerOperandIndex() { return 1U; }

  // Methods for support type inquiry through isa, cast, and dyn_cast:
  static inline bool classof(const StoreInst *) { return true; }
  static inline bool classof(const Instruction *I) {
    return I->getOpcode() == Instruction::Store;
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};

template <>
struct OperandTraits<StoreInst> : FixedNumOperandTraits<2> {
};

DEFINE_TRANSPARENT_OPERAND_ACCESSORS(StoreInst, Value)

//===----------------------------------------------------------------------===//
//                             GetElementPtrInst Class
//===----------------------------------------------------------------------===//

// checkType - Simple wrapper function to give a better assertion failure
// message on bad indexes for a gep instruction.
//
static inline const Type *checkType(const Type *Ty) {
  assert(Ty && "Invalid GetElementPtrInst indices for type!");
  return Ty;
}

/// GetElementPtrInst - an instruction for type-safe pointer arithmetic to
/// access elements of arrays and structs
///
class GetElementPtrInst : public Instruction {
  GetElementPtrInst(const GetElementPtrInst &GEPI);
  void init(Value *Ptr, Value* const *Idx, unsigned NumIdx,
            const std::string &NameStr);
  void init(Value *Ptr, Value *Idx, const std::string &NameStr);

  template<typename InputIterator>
  void init(Value *Ptr, InputIterator IdxBegin, InputIterator IdxEnd,
            const std::string &NameStr,
            // This argument ensures that we have an iterator we can
            // do arithmetic on in constant time
            std::random_access_iterator_tag) {
    unsigned NumIdx = static_cast<unsigned>(std::distance(IdxBegin, IdxEnd));
    
    if (NumIdx > 0) {
      // This requires that the iterator points to contiguous memory.
      init(Ptr, &*IdxBegin, NumIdx, NameStr); // FIXME: for the general case
                                     // we have to build an array here
    }
    else {
      init(Ptr, 0, NumIdx, NameStr);
    }
  }

  /// getIndexedType - Returns the type of the element that would be loaded with
  /// a load instruction with the specified parameters.
  ///
  /// Null is returned if the indices are invalid for the specified
  /// pointer type.
  ///
  template<typename InputIterator>
  static const Type *getIndexedType(const Type *Ptr,
                                    InputIterator IdxBegin, 
                                    InputIterator IdxEnd,
                                    // This argument ensures that we
                                    // have an iterator we can do
                                    // arithmetic on in constant time
                                    std::random_access_iterator_tag) {
    unsigned NumIdx = static_cast<unsigned>(std::distance(IdxBegin, IdxEnd));

    if (NumIdx > 0)
      // This requires that the iterator points to contiguous memory.
      return getIndexedType(Ptr, (Value *const *)&*IdxBegin, NumIdx);
    else
      return getIndexedType(Ptr, (Value *const*)0, NumIdx);
  }

  /// Constructors - Create a getelementptr instruction with a base pointer an
  /// list of indices.  The first ctor can optionally insert before an existing
  /// instruction, the second appends the new instruction to the specified
  /// BasicBlock.
  template<typename InputIterator>
  inline GetElementPtrInst(Value *Ptr, InputIterator IdxBegin, 
                           InputIterator IdxEnd,
                           unsigned Values,
                           const std::string &NameStr,
                           Instruction *InsertBefore);
  template<typename InputIterator>
  inline GetElementPtrInst(Value *Ptr,
                           InputIterator IdxBegin, InputIterator IdxEnd,
                           unsigned Values,
                           const std::string &NameStr, BasicBlock *InsertAtEnd);

  /// Constructors - These two constructors are convenience methods because one
  /// and two index getelementptr instructions are so common.
  GetElementPtrInst(Value *Ptr, Value *Idx, const std::string &NameStr = "",
                    Instruction *InsertBefore = 0);
  GetElementPtrInst(Value *Ptr, Value *Idx,
                    const std::string &NameStr, BasicBlock *InsertAtEnd);
public:
  template<typename InputIterator>
  static GetElementPtrInst *Create(Value *Ptr, InputIterator IdxBegin, 
                                   InputIterator IdxEnd,
                                   const std::string &NameStr = "",
                                   Instruction *InsertBefore = 0) {
    typename std::iterator_traits<InputIterator>::difference_type Values = 
      1 + std::distance(IdxBegin, IdxEnd);
    return new(Values)
      GetElementPtrInst(Ptr, IdxBegin, IdxEnd, Values, NameStr, InsertBefore);
  }
  template<typename InputIterator>
  static GetElementPtrInst *Create(Value *Ptr,
                                   InputIterator IdxBegin, InputIterator IdxEnd,
                                   const std::string &NameStr,
                                   BasicBlock *InsertAtEnd) {
    typename std::iterator_traits<InputIterator>::difference_type Values = 
      1 + std::distance(IdxBegin, IdxEnd);
    return new(Values)
      GetElementPtrInst(Ptr, IdxBegin, IdxEnd, Values, NameStr, InsertAtEnd);
  }

  /// Constructors - These two creators are convenience methods because one
  /// index getelementptr instructions are so common.
  static GetElementPtrInst *Create(Value *Ptr, Value *Idx,
                                   const std::string &NameStr = "",
                                   Instruction *InsertBefore = 0) {
    return new(2) GetElementPtrInst(Ptr, Idx, NameStr, InsertBefore);
  }
  static GetElementPtrInst *Create(Value *Ptr, Value *Idx,
                                   const std::string &NameStr,
                                   BasicBlock *InsertAtEnd) {
    return new(2) GetElementPtrInst(Ptr, Idx, NameStr, InsertAtEnd);
  }

  virtual GetElementPtrInst *clone() const;

  /// Transparently provide more efficient getOperand methods.
  DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);

  // getType - Overload to return most specific pointer type...
  const PointerType *getType() const {
    return reinterpret_cast<const PointerType*>(Instruction::getType());
  }

  /// getIndexedType - Returns the type of the element that would be loaded with
  /// a load instruction with the specified parameters.
  ///
  /// Null is returned if the indices are invalid for the specified
  /// pointer type.
  ///
  template<typename InputIterator>
  static const Type *getIndexedType(const Type *Ptr,
                                    InputIterator IdxBegin,
                                    InputIterator IdxEnd) {
    return getIndexedType(Ptr, IdxBegin, IdxEnd,
                          typename std::iterator_traits<InputIterator>::
                          iterator_category());
  }  

  static const Type *getIndexedType(const Type *Ptr,
                                    Value* const *Idx, unsigned NumIdx);

  static const Type *getIndexedType(const Type *Ptr,
                                    uint64_t const *Idx, unsigned NumIdx);

  static const Type *getIndexedType(const Type *Ptr, Value *Idx);

  inline op_iterator       idx_begin()       { return op_begin()+1; }
  inline const_op_iterator idx_begin() const { return op_begin()+1; }
  inline op_iterator       idx_end()         { return op_end(); }
  inline const_op_iterator idx_end()   const { return op_end(); }

  Value *getPointerOperand() {
    return getOperand(0);
  }
  const Value *getPointerOperand() const {
    return getOperand(0);
  }
  static unsigned getPointerOperandIndex() {
    return 0U;                      // get index for modifying correct operand
  }

  unsigned getNumIndices() const {  // Note: always non-negative
    return getNumOperands() - 1;
  }

  bool hasIndices() const {
    return getNumOperands() > 1;
  }
  
  /// hasAllZeroIndices - Return true if all of the indices of this GEP are
  /// zeros.  If so, the result pointer and the first operand have the same
  /// value, just potentially different types.
  bool hasAllZeroIndices() const;
  
  /// hasAllConstantIndices - Return true if all of the indices of this GEP are
  /// constant integers.  If so, the result pointer and the first operand have
  /// a constant offset between them.
  bool hasAllConstantIndices() const;
  

  // Methods for support type inquiry through isa, cast, and dyn_cast:
  static inline bool classof(const GetElementPtrInst *) { return true; }
  static inline bool classof(const Instruction *I) {
    return (I->getOpcode() == Instruction::GetElementPtr);
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};

template <>
struct OperandTraits<GetElementPtrInst> : VariadicOperandTraits<1> {
};

template<typename InputIterator>
GetElementPtrInst::GetElementPtrInst(Value *Ptr,
                                     InputIterator IdxBegin, 
                                     InputIterator IdxEnd,
                                     unsigned Values,
                                     const std::string &NameStr,
                                     Instruction *InsertBefore)
  : Instruction(PointerType::get(checkType(
                                   getIndexedType(Ptr->getType(),
                                                  IdxBegin, IdxEnd)),
                                 cast<PointerType>(Ptr->getType())
                                   ->getAddressSpace()),
                GetElementPtr,
                OperandTraits<GetElementPtrInst>::op_end(this) - Values,
                Values, InsertBefore) {
  init(Ptr, IdxBegin, IdxEnd, NameStr,
       typename std::iterator_traits<InputIterator>::iterator_category());
}
template<typename InputIterator>
GetElementPtrInst::GetElementPtrInst(Value *Ptr,
                                     InputIterator IdxBegin,
                                     InputIterator IdxEnd,
                                     unsigned Values,
                                     const std::string &NameStr,
                                     BasicBlock *InsertAtEnd)
  : Instruction(PointerType::get(checkType(
                                   getIndexedType(Ptr->getType(),
                                                  IdxBegin, IdxEnd)),
                                 cast<PointerType>(Ptr->getType())
                                   ->getAddressSpace()),
                GetElementPtr,
                OperandTraits<GetElementPtrInst>::op_end(this) - Values,
                Values, InsertAtEnd) {
  init(Ptr, IdxBegin, IdxEnd, NameStr,
       typename std::iterator_traits<InputIterator>::iterator_category());
}


DEFINE_TRANSPARENT_OPERAND_ACCESSORS(GetElementPtrInst, Value)


//===----------------------------------------------------------------------===//
//                               ICmpInst Class
//===----------------------------------------------------------------------===//

/// This instruction compares its operands according to the predicate given
/// to the constructor. It only operates on integers or pointers. The operands
/// must be identical types.
/// @brief Represent an integer comparison operator.
class ICmpInst: public CmpInst {
public:
  /// @brief Constructor with insert-before-instruction semantics.
  ICmpInst(
    Predicate pred,  ///< The predicate to use for the comparison
    Value *LHS,      ///< The left-hand-side of the expression
    Value *RHS,      ///< The right-hand-side of the expression
    const std::string &NameStr = "",  ///< Name of the instruction
    Instruction *InsertBefore = 0  ///< Where to insert
  ) : CmpInst(Type::Int1Ty, Instruction::ICmp, pred, LHS, RHS, NameStr,
              InsertBefore) {
    assert(pred >= CmpInst::FIRST_ICMP_PREDICATE &&
           pred <= CmpInst::LAST_ICMP_PREDICATE &&
           "Invalid ICmp predicate value");
    assert(getOperand(0)->getType() == getOperand(1)->getType() &&
          "Both operands to ICmp instruction are not of the same type!");
    // Check that the operands are the right type
    assert((getOperand(0)->getType()->isInteger() || 
            isa<PointerType>(getOperand(0)->getType())) &&
           "Invalid operand types for ICmp instruction");
  }

  /// @brief Constructor with insert-at-block-end semantics.
  ICmpInst(
    Predicate pred, ///< The predicate to use for the comparison
    Value *LHS,     ///< The left-hand-side of the expression
    Value *RHS,     ///< The right-hand-side of the expression
    const std::string &NameStr,  ///< Name of the instruction
    BasicBlock *InsertAtEnd   ///< Block to insert into.
  ) : CmpInst(Type::Int1Ty, Instruction::ICmp, pred, LHS, RHS, NameStr,
              InsertAtEnd) {
    assert(pred >= CmpInst::FIRST_ICMP_PREDICATE &&
           pred <= CmpInst::LAST_ICMP_PREDICATE &&
           "Invalid ICmp predicate value");
    assert(getOperand(0)->getType() == getOperand(1)->getType() &&
          "Both operands to ICmp instruction are not of the same type!");
    // Check that the operands are the right type
    assert((getOperand(0)->getType()->isInteger() || 
            isa<PointerType>(getOperand(0)->getType())) &&
           "Invalid operand types for ICmp instruction");
  }

  /// For example, EQ->EQ, SLE->SLE, UGT->SGT, etc.
  /// @returns the predicate that would be the result if the operand were
  /// regarded as signed.
  /// @brief Return the signed version of the predicate
  Predicate getSignedPredicate() const {
    return getSignedPredicate(getPredicate());
  }

  /// This is a static version that you can use without an instruction.
  /// @brief Return the signed version of the predicate.
  static Predicate getSignedPredicate(Predicate pred);

  /// For example, EQ->EQ, SLE->ULE, UGT->UGT, etc.
  /// @returns the predicate that would be the result if the operand were
  /// regarded as unsigned.
  /// @brief Return the unsigned version of the predicate
  Predicate getUnsignedPredicate() const {
    return getUnsignedPredicate(getPredicate());
  }

  /// This is a static version that you can use without an instruction.
  /// @brief Return the unsigned version of the predicate.
  static Predicate getUnsignedPredicate(Predicate pred);

  /// isEquality - Return true if this predicate is either EQ or NE.  This also
  /// tests for commutativity.
  static bool isEquality(Predicate P) {
    return P == ICMP_EQ || P == ICMP_NE;
  }
  
  /// isEquality - Return true if this predicate is either EQ or NE.  This also
  /// tests for commutativity.
  bool isEquality() const {
    return isEquality(getPredicate());
  }

  /// @returns true if the predicate of this ICmpInst is commutative
  /// @brief Determine if this relation is commutative.
  bool isCommutative() const { return isEquality(); }

  /// isRelational - Return true if the predicate is relational (not EQ or NE). 
  ///
  bool isRelational() const {
    return !isEquality();
  }

  /// isRelational - Return true if the predicate is relational (not EQ or NE). 
  ///
  static bool isRelational(Predicate P) {
    return !isEquality(P);
  }
  
  /// @returns true if the predicate of this ICmpInst is signed, false otherwise
  /// @brief Determine if this instruction's predicate is signed.
  bool isSignedPredicate() const { return isSignedPredicate(getPredicate()); }

  /// @returns true if the predicate provided is signed, false otherwise
  /// @brief Determine if the predicate is signed.
  static bool isSignedPredicate(Predicate pred);

  /// @returns true if the specified compare predicate is
  /// true when both operands are equal...
  /// @brief Determine if the icmp is true when both operands are equal
  static bool isTrueWhenEqual(ICmpInst::Predicate pred) {
    return pred == ICmpInst::ICMP_EQ  || pred == ICmpInst::ICMP_UGE ||
           pred == ICmpInst::ICMP_SGE || pred == ICmpInst::ICMP_ULE ||
           pred == ICmpInst::ICMP_SLE;
  }

  /// @returns true if the specified compare instruction is
  /// true when both operands are equal...
  /// @brief Determine if the ICmpInst returns true when both operands are equal
  bool isTrueWhenEqual() {
    return isTrueWhenEqual(getPredicate());
  }

  /// Initialize a set of values that all satisfy the predicate with C. 
  /// @brief Make a ConstantRange for a relation with a constant value.
  static ConstantRange makeConstantRange(Predicate pred, const APInt &C);

  /// Exchange the two operands to this instruction in such a way that it does
  /// not modify the semantics of the instruction. The predicate value may be
  /// changed to retain the same result if the predicate is order dependent
  /// (e.g. ult). 
  /// @brief Swap operands and adjust predicate.
  void swapOperands() {
    SubclassData = getSwappedPredicate();
    Op<0>().swap(Op<1>());
  }

  virtual ICmpInst *clone() const;

  // Methods for support type inquiry through isa, cast, and dyn_cast:
  static inline bool classof(const ICmpInst *) { return true; }
  static inline bool classof(const Instruction *I) {
    return I->getOpcode() == Instruction::ICmp;
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};

//===----------------------------------------------------------------------===//
//                               FCmpInst Class
//===----------------------------------------------------------------------===//

/// This instruction compares its operands according to the predicate given
/// to the constructor. It only operates on floating point values or packed     
/// vectors of floating point values. The operands must be identical types.
/// @brief Represents a floating point comparison operator.
class FCmpInst: public CmpInst {
public:
  /// @brief Constructor with insert-before-instruction semantics.
  FCmpInst(
    Predicate pred,  ///< The predicate to use for the comparison
    Value *LHS,      ///< The left-hand-side of the expression
    Value *RHS,      ///< The right-hand-side of the expression
    const std::string &NameStr = "",  ///< Name of the instruction
    Instruction *InsertBefore = 0  ///< Where to insert
  ) : CmpInst(Type::Int1Ty, Instruction::FCmp, pred, LHS, RHS, NameStr,
              InsertBefore) {
    assert(pred <= FCmpInst::LAST_FCMP_PREDICATE &&
           "Invalid FCmp predicate value");
    assert(getOperand(0)->getType() == getOperand(1)->getType() &&
           "Both operands to FCmp instruction are not of the same type!");
    // Check that the operands are the right type
    assert(getOperand(0)->getType()->isFloatingPoint() &&
           "Invalid operand types for FCmp instruction");
  }

  /// @brief Constructor with insert-at-block-end semantics.
  FCmpInst(
    Predicate pred, ///< The predicate to use for the comparison
    Value *LHS,     ///< The left-hand-side of the expression
    Value *RHS,     ///< The right-hand-side of the expression
    const std::string &NameStr,  ///< Name of the instruction
    BasicBlock *InsertAtEnd   ///< Block to insert into.
  ) : CmpInst(Type::Int1Ty, Instruction::FCmp, pred, LHS, RHS, NameStr,
              InsertAtEnd) {
    assert(pred <= FCmpInst::LAST_FCMP_PREDICATE &&
           "Invalid FCmp predicate value");
    assert(getOperand(0)->getType() == getOperand(1)->getType() &&
           "Both operands to FCmp instruction are not of the same type!");
    // Check that the operands are the right type
    assert(getOperand(0)->getType()->isFloatingPoint() &&
           "Invalid operand types for FCmp instruction");
  }

  /// This also tests for commutativity. If isEquality() returns true then
  /// the predicate is also commutative. Only the equality predicates are
  /// commutative.
  /// @returns true if the predicate of this instruction is EQ or NE.
  /// @brief Determine if this is an equality predicate.
  bool isEquality() const {
    return SubclassData == FCMP_OEQ || SubclassData == FCMP_ONE ||
           SubclassData == FCMP_UEQ || SubclassData == FCMP_UNE;
  }
  bool isCommutative() const { return isEquality(); }

  /// @returns true if the predicate is relational (not EQ or NE). 
  /// @brief Determine if this a relational predicate.
  bool isRelational() const { return !isEquality(); }

  /// Exchange the two operands to this instruction in such a way that it does
  /// not modify the semantics of the instruction. The predicate value may be
  /// changed to retain the same result if the predicate is order dependent
  /// (e.g. ult). 
  /// @brief Swap operands and adjust predicate.
  void swapOperands() {
    SubclassData = getSwappedPredicate();
    Op<0>().swap(Op<1>());
  }

  virtual FCmpInst *clone() const;

  /// @brief Methods for support type inquiry through isa, cast, and dyn_cast:
  static inline bool classof(const FCmpInst *) { return true; }
  static inline bool classof(const Instruction *I) {
    return I->getOpcode() == Instruction::FCmp;
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};

//===----------------------------------------------------------------------===//
//                               VICmpInst Class
//===----------------------------------------------------------------------===//

/// This instruction compares its operands according to the predicate given
/// to the constructor. It only operates on vectors of integers.
/// The operands must be identical types.
/// @brief Represents a vector integer comparison operator.
class VICmpInst: public CmpInst {
public:
  /// @brief Constructor with insert-before-instruction semantics.
  VICmpInst(
    Predicate pred,  ///< The predicate to use for the comparison
    Value *LHS,      ///< The left-hand-side of the expression
    Value *RHS,      ///< The right-hand-side of the expression
    const std::string &NameStr = "",  ///< Name of the instruction
    Instruction *InsertBefore = 0  ///< Where to insert
  ) : CmpInst(LHS->getType(), Instruction::VICmp, pred, LHS, RHS, NameStr,
              InsertBefore) {
    assert(pred >= CmpInst::FIRST_ICMP_PREDICATE &&
           pred <= CmpInst::LAST_ICMP_PREDICATE &&
           "Invalid VICmp predicate value");
    assert(getOperand(0)->getType() == getOperand(1)->getType() &&
          "Both operands to VICmp instruction are not of the same type!");
  }

  /// @brief Constructor with insert-at-block-end semantics.
  VICmpInst(
    Predicate pred, ///< The predicate to use for the comparison
    Value *LHS,     ///< The left-hand-side of the expression
    Value *RHS,     ///< The right-hand-side of the expression
    const std::string &NameStr,  ///< Name of the instruction
    BasicBlock *InsertAtEnd   ///< Block to insert into.
  ) : CmpInst(LHS->getType(), Instruction::VICmp, pred, LHS, RHS, NameStr,
              InsertAtEnd) {
    assert(pred >= CmpInst::FIRST_ICMP_PREDICATE &&
           pred <= CmpInst::LAST_ICMP_PREDICATE &&
           "Invalid VICmp predicate value");
    assert(getOperand(0)->getType() == getOperand(1)->getType() &&
          "Both operands to VICmp instruction are not of the same type!");
  }
  
  /// @brief Return the predicate for this instruction.
  Predicate getPredicate() const { return Predicate(SubclassData); }

  virtual VICmpInst *clone() const;

  // Methods for support type inquiry through isa, cast, and dyn_cast:
  static inline bool classof(const VICmpInst *) { return true; }
  static inline bool classof(const Instruction *I) {
    return I->getOpcode() == Instruction::VICmp;
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};

//===----------------------------------------------------------------------===//
//                               VFCmpInst Class
//===----------------------------------------------------------------------===//

/// This instruction compares its operands according to the predicate given
/// to the constructor. It only operates on vectors of floating point values.
/// The operands must be identical types.
/// @brief Represents a vector floating point comparison operator.
class VFCmpInst: public CmpInst {
public:
  /// @brief Constructor with insert-before-instruction semantics.
  VFCmpInst(
    Predicate pred,  ///< The predicate to use for the comparison
    Value *LHS,      ///< The left-hand-side of the expression
    Value *RHS,      ///< The right-hand-side of the expression
    const std::string &NameStr = "",  ///< Name of the instruction
    Instruction *InsertBefore = 0  ///< Where to insert
  ) : CmpInst(VectorType::getInteger(cast<VectorType>(LHS->getType())),
              Instruction::VFCmp, pred, LHS, RHS, NameStr, InsertBefore) {
    assert(pred <= CmpInst::LAST_FCMP_PREDICATE &&
           "Invalid VFCmp predicate value");
    assert(getOperand(0)->getType() == getOperand(1)->getType() &&
           "Both operands to VFCmp instruction are not of the same type!");
  }

  /// @brief Constructor with insert-at-block-end semantics.
  VFCmpInst(
    Predicate pred, ///< The predicate to use for the comparison
    Value *LHS,     ///< The left-hand-side of the expression
    Value *RHS,     ///< The right-hand-side of the expression
    const std::string &NameStr,  ///< Name of the instruction
    BasicBlock *InsertAtEnd   ///< Block to insert into.
  ) : CmpInst(VectorType::getInteger(cast<VectorType>(LHS->getType())),
              Instruction::VFCmp, pred, LHS, RHS, NameStr, InsertAtEnd) {
    assert(pred <= CmpInst::LAST_FCMP_PREDICATE &&
           "Invalid VFCmp predicate value");
    assert(getOperand(0)->getType() == getOperand(1)->getType() &&
           "Both operands to VFCmp instruction are not of the same type!");
  }

  /// @brief Return the predicate for this instruction.
  Predicate getPredicate() const { return Predicate(SubclassData); }

  virtual VFCmpInst *clone() const;

  /// @brief Methods for support type inquiry through isa, cast, and dyn_cast:
  static inline bool classof(const VFCmpInst *) { return true; }
  static inline bool classof(const Instruction *I) {
    return I->getOpcode() == Instruction::VFCmp;
  }
  static inline bool classof(const Value *V) {
    return isa<Instruction>(V) && classof(cast<Instruction>(V));
  }
};

//===----------------------------------------------------------------------===//
//                                 CallInst Class
//===----------------------------------------------------------------------===//
/// CallInst - This class represents a function call, abstracting a target
/// machine's calling convention.  This class uses low bit of the SubClassData
/// field to indicate whether or not this is a tail call.  The rest of the bits
/// hold the calling convention of the call.
///

class CallInst : public Instruction {
  PAListPtr ParamAttrs; ///< parameter attributes for call
  CallInst(const CallInst &CI);
  void init(Value *Func, Value* const *Params, unsigned NumParams);
  void init(Value *Func, Value *Actual1, Value *Actual2);
  void init(Value *Func, Value *Actual);
  void init(Value *Func);

  template<typename InputIterator>
  void init(Value *Func, InputIterator ArgBegin, InputIterator ArgEnd,
            const std::string &NameStr,
            // This argument ensures that we have an iterator we can
            // do arithmetic on in constant time
            std::random_access_iterator_tag) {
    unsigned NumArgs = (unsigned)std::distance(ArgBegin, ArgEnd);
    
    // This requires that the iterator points to contiguous memory.
    init(Func, NumArgs ? &*ArgBegin : 0, NumArgs);
    setName(NameStr);
  }

  /// Construct a CallInst given a range of arguments.  InputIterator
  /// must be a random-access iterator pointing to contiguous storage
  /// (e.g. a std::vector<>::iterator).  Checks are made for
  /// random-accessness but not for contiguous storage as that would
  /// incur runtime overhead.
  /// @brief Construct a CallInst from a range of arguments
  template<typename InputIterator>
  CallInst(Value *Func, InputIterator ArgBegin, InputIterator ArgEnd,
           const std::string &NameStr, Instruction *InsertBefore);

  /// Construct a CallInst given a range of arguments.  InputIterator
  /// must be a random-access iterator pointing to contiguous storage
  /// (e.g. a std::vector<>::iterator).  Checks are made for
  /// random-accessness but not for contiguous storage as that would
  /// incur runtime overhead.
  /// @brief Construct a CallInst from a range of arguments
  template<typename InputIterator>
  inline CallInst(Value *Func, InputIterator ArgBegin, InputIterator ArgEnd,
                  const std::string &NameStr, BasicBlock *InsertAtEnd);

  CallInst(Value *F, Value *Actual, const std::string& NameStr,
           Instruction *InsertBefore);
  CallInst(Value *F, Value *Actual, const std::string& NameStr,
           BasicBlock *InsertAtEnd);
  explicit CallInst(Value *F, const std::string &NameStr,
                    Instruction *InsertBefore);
  CallInst(Value *F, const std::string &NameStr, BasicBlock *InsertAtEnd);
public:
  template<typename InputIterator>
  static CallInst *Create(Value *Func,
                          InputIterator ArgBegin, InputIterator ArgEnd,
                          const std::string &NameStr = "",
                          Instruction *InsertBefore = 0) {
    return new((unsigned)(ArgEnd - ArgBegin + 1))
      CallInst(Func, ArgBegin, ArgEnd, NameStr, InsertBefore);
  }
  template<typename InputIterator>
  static CallInst *Create(Value *Func,
                          InputIterator ArgBegin, InputIterator ArgEnd,
                          const std::string &NameStr, BasicBlock *InsertAtEnd) {
    return new((unsigned)(ArgEnd - ArgBegin + 1))
      CallInst(Func, ArgBegin, ArgEnd, NameStr, InsertAtEnd);
  }
  static CallInst *Create(Value *F, Value *Actual,
                          const std::string& NameStr = "",
                          Instruction *InsertBefore = 0) {
    return new(2) CallInst(F, Actual, NameStr, InsertBefore);
  }
  static CallInst *Create(Value *F, Value *Actual, const std::string& NameStr,
                          BasicBlock *InsertAtEnd) {
    return new(2) CallInst(F, Actual, NameStr, InsertAtEnd);
  }
  static CallInst *Create(Value *F, const std::string &NameStr = "",
                          Instruction *InsertBefore = 0) {
    return new(1) CallInst(F, NameStr, InsertBefore);
  }
  static CallInst *Create(Value *F, const std::string &NameStr,
                          BasicBlock *InsertAtEnd) {
    return new(1) CallInst(F, NameStr, InsertAtEnd);
  }

  ~CallInst();

  virtual CallInst *clone() const;

  /// Provide fast operand accessors
  DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
  
  bool isTailCall() const           { return SubclassData & 1; }
  void setTailCall(bool isTC = true) {
    SubclassData = (SubclassData & ~1) | unsigned(isTC);
  }

  /// getCallingConv/setCallingConv - Get or set the calling convention of this
  /// function call.
  unsigned getCallingConv() const { return SubclassData >> 1; }
  void setCallingConv(unsigned CC) {
    SubclassData = (SubclassData & 1) | (CC << 1);
  }

  /// getParamAttrs - Return the parameter attributes for this call.
  ///
  const PAListPtr &getParamAttrs() const { return ParamAttrs; }

  /// setParamAttrs - Sets the parameter attributes for this call.
  void setParamAttrs(const PAListPtr &Attrs) { ParamAttrs = Attrs; }
  
  /// addParamAttr - adds the attribute to the list of attributes.
  void addParamAttr(unsigned i, ParameterAttributes attr);

  /// removeParamAttr - removes the attribute from the list of attributes.
  void removeParamAttr(unsigned i, ParameterAttributes attr);

  /// @brief Determine whether the call or the callee has the given attribute.
  bool paramHasAttr(unsigned i, unsigned attr) const;

  /// @brief Extract the alignment for a call or parameter (0=unknown).
  unsigned getParamAlignment(unsigned i) const {
    return ParamAttrs.getParamAlignment(i);
  }

  /// @brief Deter