X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FInstrTypes.h;h=1ee2a4b33180ab63001cb34d46c4d935e2f7417c;hb=7886ae9e3ca7ec20eceb213523a6788d368cfc73;hp=8d1b5f1230dce8e8353c67a28e36c7d90f28a951;hpb=dc1e020444942b1dc721a84b21f5d634689762a5;p=oota-llvm.git

diff --git a/include/llvm/InstrTypes.h b/include/llvm/InstrTypes.h
index 8d1b5f1230d..1ee2a4b3318 100644
--- a/include/llvm/InstrTypes.h
+++ b/include/llvm/InstrTypes.h
@@ -1,7 +1,14 @@
-//===-- llvm/InstrTypes.h - Important Instruction subclasses -----*- C++ -*--=//
+//===-- llvm/InstrTypes.h - Important Instruction subclasses ----*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
 //
 // This file defines various meta classes of instructions that exist in the VM
-// representation.  Specific concrete subclasses of these may be found in the 
+// representation.  Specific concrete subclasses of these may be found in the
 // i*.h files...
 //
 //===----------------------------------------------------------------------===//
@@ -10,42 +17,65 @@
 #define LLVM_INSTRUCTION_TYPES_H
 
 #include "llvm/Instruction.h"
+#include "llvm/OperandTraits.h"
+#include "llvm/DerivedTypes.h"
+
+namespace llvm {
+
+class LLVMContext;
 
 //===----------------------------------------------------------------------===//
 //                            TerminatorInst Class
 //===----------------------------------------------------------------------===//
 
-// TerminatorInst - Subclasses of this class are all able to terminate a basic 
-// block.  Thus, these are all the flow control type of operations.
-//
+/// TerminatorInst - Subclasses of this class are all able to terminate a basic
+/// block.  Thus, these are all the flow control type of operations.
+///
 class TerminatorInst : public Instruction {
 protected:
-  TerminatorInst(Instruction::TermOps iType);
   TerminatorInst(const Type *Ty, Instruction::TermOps iType,
-                 const std::string &Name = "");
+                 Use *Ops, unsigned NumOps,
+                 Instruction *InsertBefore = 0)
+    : Instruction(Ty, iType, Ops, NumOps, InsertBefore) {}
+
+  TerminatorInst(const Type *Ty, Instruction::TermOps iType,
+                 Use *Ops, unsigned NumOps, BasicBlock *InsertAtEnd)
+    : Instruction(Ty, iType, Ops, NumOps, InsertAtEnd) {}
+
+  // Out of line virtual method, so the vtable, etc has a home.
+  ~TerminatorInst();
+
+  /// Virtual methods - Terminators should overload these and provide inline
+  /// overrides of non-V methods.
+  virtual BasicBlock *getSuccessorV(unsigned idx) const = 0;
+  virtual unsigned getNumSuccessorsV() const = 0;
+  virtual void setSuccessorV(unsigned idx, BasicBlock *B) = 0;
 public:
 
-  // Terminators must implement the methods required by Instruction...
-  virtual Instruction *clone() const = 0;
+  virtual Instruction *clone(LLVMContext &Context) const = 0;
 
-  // Additionally, they must provide a method to get at the successors of this
-  // terminator instruction.  'idx' may not be >= the number of successors
-  // returned by getNumSuccessors()!
-  //
-  virtual const BasicBlock *getSuccessor(unsigned idx) const = 0;
-  virtual unsigned getNumSuccessors() const = 0;
-  
-  // Set a successor at a given index
-  virtual void setSuccessor(unsigned idx, BasicBlock *B) = 0;
+  /// getNumSuccessors - Return the number of successors that this terminator
+  /// has.
+  unsigned getNumSuccessors() const {
+    return getNumSuccessorsV();
+  }
 
-  inline BasicBlock *getSuccessor(unsigned idx) {
-    return (BasicBlock*)((const TerminatorInst *)this)->getSuccessor(idx);
+  /// getSuccessor - Return the specified successor.
+  ///
+  BasicBlock *getSuccessor(unsigned idx) const {
+    return getSuccessorV(idx);
+  }
+
+  /// setSuccessor - Update the specified successor to point at the provided
+  /// block.
+  void setSuccessor(unsigned idx, BasicBlock *B) {
+    setSuccessorV(idx, B);
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const TerminatorInst *) { return true; }
   static inline bool classof(const Instruction *I) {
-    return I->getOpcode() >= FirstTermOp && I->getOpcode() < NumTermOps; 
+    return I->isTerminator();
   }
   static inline bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
@@ -54,93 +84,601 @@ public:
 
 
 //===----------------------------------------------------------------------===//
-//                            UnaryOperator Class
+//                          UnaryInstruction Class
 //===----------------------------------------------------------------------===//
 
-class UnaryOperator : public Instruction {
+class UnaryInstruction : public Instruction {
+  void *operator new(size_t, unsigned);      // Do not implement
+  UnaryInstruction(const UnaryInstruction&); // Do not implement
+
 protected:
-  UnaryOperator(Value *S, UnaryOps iType, const std::string &Name = "")
-      : Instruction(S->getType(), iType, Name) {
-    Operands.reserve(1);
-    Operands.push_back(Use(S, this));
+  UnaryInstruction(const Type *Ty, unsigned iType, Value *V,
+                   Instruction *IB = 0)
+    : Instruction(Ty, iType, &Op<0>(), 1, IB) {
+    Op<0>() = V;
+  }
+  UnaryInstruction(const Type *Ty, unsigned iType, Value *V, BasicBlock *IAE)
+    : Instruction(Ty, iType, &Op<0>(), 1, IAE) {
+    Op<0>() = V;
   }
 public:
-
-  // create() - Construct a unary instruction, given the opcode
-  // and its operand.
-  //
-  static UnaryOperator *create(UnaryOps Op, Value *Source,
-                               const std::string &Name = "");
-
-  inline UnaryOps getOpcode() const { 
-    return (UnaryOps)Instruction::getOpcode();
+  // allocate space for exactly one operand
+  void *operator new(size_t s) {
+    return User::operator new(s, 1);
   }
 
-  virtual Instruction *clone() const { 
-    return create(getOpcode(), Operands[0]);
-  }
+  // Out of line virtual method, so the vtable, etc has a home.
+  ~UnaryInstruction();
+
+  /// Transparently provide more efficient getOperand methods.
+  DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
-  static inline bool classof(const UnaryOperator *) { return true; }
+  static inline bool classof(const UnaryInstruction *) { return true; }
   static inline bool classof(const Instruction *I) {
-    return I->getOpcode() >= FirstUnaryOp && I->getOpcode() < NumUnaryOps; 
+    return I->getOpcode() == Instruction::Malloc ||
+           I->getOpcode() == Instruction::Alloca ||
+           I->getOpcode() == Instruction::Free ||
+           I->getOpcode() == Instruction::Load ||
+           I->getOpcode() == Instruction::VAArg ||
+           I->getOpcode() == Instruction::ExtractValue ||
+           (I->getOpcode() >= CastOpsBegin && I->getOpcode() < CastOpsEnd);
   }
   static inline bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
+template <>
+struct OperandTraits<UnaryInstruction> : FixedNumOperandTraits<1> {
+};
 
+DEFINE_TRANSPARENT_OPERAND_ACCESSORS(UnaryInstruction, Value)
 
 //===----------------------------------------------------------------------===//
 //                           BinaryOperator Class
 //===----------------------------------------------------------------------===//
 
 class BinaryOperator : public Instruction {
+  void *operator new(size_t, unsigned); // Do not implement
 protected:
-  BinaryOperator(BinaryOps iType, Value *S1, Value *S2, 
-                 const std::string &Name = "") 
-    : Instruction(S1->getType(), iType, Name) {
-    Operands.reserve(2);
-    Operands.push_back(Use(S1, this));
-    Operands.push_back(Use(S2, this));
-    assert(Operands[0] && Operands[1] && 
-	   Operands[0]->getType() == Operands[1]->getType());
+  void init(BinaryOps iType);
+  BinaryOperator(BinaryOps iType, Value *S1, Value *S2, const Type *Ty,
+                 const std::string &Name, Instruction *InsertBefore);
+  BinaryOperator(BinaryOps iType, Value *S1, Value *S2, const Type *Ty,
+                 const std::string &Name, BasicBlock *InsertAtEnd);
+public:
+  // allocate space for exactly two operands
+  void *operator new(size_t s) {
+    return User::operator new(s, 2);
   }
 
-public:
+  /// Transparently provide more efficient getOperand methods.
+  DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
+
+  /// Create() - Construct a binary instruction, given the opcode and the two
+  /// operands.  Optionally (if InstBefore is specified) insert the instruction
+  /// into a BasicBlock right before the specified instruction.  The specified
+  /// Instruction is allowed to be a dereferenced end iterator.
+  ///
+  static BinaryOperator *Create(BinaryOps Op, Value *S1, Value *S2,
+                                const std::string &Name = "",
+                                Instruction *InsertBefore = 0);
 
-  // create() - Construct a binary instruction, given the opcode
-  // and the two operands.
-  //
-  static BinaryOperator *create(BinaryOps Op, Value *S1, Value *S2,
-				const std::string &Name = "");
+  /// Create() - Construct a binary instruction, given the opcode and the two
+  /// operands.  Also automatically insert this instruction to the end of the
+  /// BasicBlock specified.
+  ///
+  static BinaryOperator *Create(BinaryOps Op, Value *S1, Value *S2,
+                                const std::string &Name,
+                                BasicBlock *InsertAtEnd);
 
-  inline BinaryOps getOpcode() const { 
-    return (BinaryOps)Instruction::getOpcode();
+  /// Create* - These methods just forward to Create, and are useful when you
+  /// statically know what type of instruction you're going to create.  These
+  /// helpers just save some typing.
+#define HANDLE_BINARY_INST(N, OPC, CLASS) \
+  static BinaryOperator *Create##OPC(Value *V1, Value *V2, \
+                                     const std::string &Name = "") {\
+    return Create(Instruction::OPC, V1, V2, Name);\
+  }
+#include "llvm/Instruction.def"
+#define HANDLE_BINARY_INST(N, OPC, CLASS) \
+  static BinaryOperator *Create##OPC(Value *V1, Value *V2, \
+                                     const std::string &Name, BasicBlock *BB) {\
+    return Create(Instruction::OPC, V1, V2, Name, BB);\
+  }
+#include "llvm/Instruction.def"
+#define HANDLE_BINARY_INST(N, OPC, CLASS) \
+  static BinaryOperator *Create##OPC(Value *V1, Value *V2, \
+                                     const std::string &Name, Instruction *I) {\
+    return Create(Instruction::OPC, V1, V2, Name, I);\
   }
+#include "llvm/Instruction.def"
+
+
+  /// Helper functions to construct and inspect unary operations (NEG and NOT)
+  /// via binary operators SUB and XOR:
+  ///
+  /// CreateNeg, CreateNot - Create the NEG and NOT
+  ///     instructions out of SUB and XOR instructions.
+  ///
+  static BinaryOperator *CreateNeg(LLVMContext &Context,
+                                   Value *Op, const std::string &Name = "",
+                                   Instruction *InsertBefore = 0);
+  static BinaryOperator *CreateNeg(LLVMContext &Context,
+                                   Value *Op, const std::string &Name,
+                                   BasicBlock *InsertAtEnd);
+  static BinaryOperator *CreateFNeg(LLVMContext &Context, 
+                                    Value *Op, const std::string &Name = "",
+                                    Instruction *InsertBefore = 0);
+  static BinaryOperator *CreateFNeg(LLVMContext &Context,
+                                    Value *Op, const std::string &Name,
+                                    BasicBlock *InsertAtEnd);
+  static BinaryOperator *CreateNot(LLVMContext &Context,
+                                   Value *Op, const std::string &Name = "",
+                                   Instruction *InsertBefore = 0);
+  static BinaryOperator *CreateNot(LLVMContext &Context,
+                                   Value *Op, const std::string &Name,
+                                   BasicBlock *InsertAtEnd);
+
+  /// isNeg, isFNeg, isNot - Check if the given Value is a
+  /// NEG, FNeg, or NOT instruction.
+  ///
+  static bool isNeg(const Value *V);
+  static bool isFNeg(const Value *V);
+  static bool isNot(const Value *V);
 
-  virtual Instruction *clone() const {
-    return create(getOpcode(), Operands[0], Operands[1]);
+  /// getNegArgument, getNotArgument - Helper functions to extract the
+  ///     unary argument of a NEG, FNEG or NOT operation implemented via
+  ///     Sub, FSub, or Xor.
+  ///
+  static const Value *getNegArgument(const Value *BinOp);
+  static       Value *getNegArgument(      Value *BinOp);
+  static const Value *getFNegArgument(const Value *BinOp);
+  static       Value *getFNegArgument(      Value *BinOp);
+  static const Value *getNotArgument(const Value *BinOp);
+  static       Value *getNotArgument(      Value *BinOp);
+
+  BinaryOps getOpcode() const {
+    return static_cast<BinaryOps>(Instruction::getOpcode());
   }
 
-  // swapOperands - Exchange the two operands to this instruction.
-  // This instruction is safe to use on any binary instruction and
-  // does not modify the semantics of the instruction.  If the
-  // instruction is order dependant (SetLT f.e.) the opcode is
-  // changed.  If the instruction cannot be reversed (ie, it's a Div),
-  // then return true.
-  //
+  virtual BinaryOperator *clone(LLVMContext &Context) const;
+
+  /// swapOperands - Exchange the two operands to this instruction.
+  /// This instruction is safe to use on any binary instruction and
+  /// does not modify the semantics of the instruction.  If the instruction
+  /// cannot be reversed (ie, it's a Div), then return true.
+  ///
   bool swapOperands();
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const BinaryOperator *) { return true; }
   static inline bool classof(const Instruction *I) {
-    return I->getOpcode() >= FirstBinaryOp && I->getOpcode() < NumBinaryOps; 
+    return I->isBinaryOp();
   }
   static inline bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
+template <>
+struct OperandTraits<BinaryOperator> : FixedNumOperandTraits<2> {
+};
+
+DEFINE_TRANSPARENT_OPERAND_ACCESSORS(BinaryOperator, Value)
+
+//===----------------------------------------------------------------------===//
+//                               CastInst Class
+//===----------------------------------------------------------------------===//
+
+/// CastInst - This is the base class for all instructions that perform data
+/// casts. It is simply provided so that instruction category testing
+/// can be performed with code like:
+///
+/// if (isa<CastInst>(Instr)) { ... }
+/// @brief Base class of casting instructions.
+class CastInst : public UnaryInstruction {
+  /// @brief Copy constructor
+  CastInst(const CastInst &CI)
+    : UnaryInstruction(CI.getType(), CI.getOpcode(), CI.getOperand(0)) {
+  }
+  /// @brief Do not allow default construction
+  CastInst();
+protected:
+  /// @brief Constructor with insert-before-instruction semantics for subclasses
+  CastInst(const Type *Ty, unsigned iType, Value *S,
+           const std::string &NameStr = "", Instruction *InsertBefore = 0)
+    : UnaryInstruction(Ty, iType, S, InsertBefore) {
+    setName(NameStr);
+  }
+  /// @brief Constructor with insert-at-end-of-block semantics for subclasses
+  CastInst(const Type *Ty, unsigned iType, Value *S,
+           const std::string &NameStr, BasicBlock *InsertAtEnd)
+    : UnaryInstruction(Ty, iType, S, InsertAtEnd) {
+    setName(NameStr);
+  }
+public:
+  /// Provides a way to construct any of the CastInst subclasses using an
+  /// opcode instead of the subclass's constructor. The opcode must be in the
+  /// CastOps category (Instruction::isCast(opcode) returns true). This
+  /// constructor has insert-before-instruction semantics to automatically
+  /// insert the new CastInst before InsertBefore (if it is non-null).
+  /// @brief Construct any of the CastInst subclasses
+  static CastInst *Create(
+    Instruction::CastOps,    ///< The opcode of the cast instruction
+    Value *S,                ///< The value to be casted (operand 0)
+    const Type *Ty,          ///< The type to which cast should be made
+    const std::string &Name = "", ///< Name for the instruction
+    Instruction *InsertBefore = 0 ///< Place to insert the instruction
+  );
+  /// Provides a way to construct any of the CastInst subclasses using an
+  /// opcode instead of the subclass's constructor. The opcode must be in the
+  /// CastOps category. This constructor has insert-at-end-of-block semantics
+  /// to automatically insert the new CastInst at the end of InsertAtEnd (if
+  /// its non-null).
+  /// @brief Construct any of the CastInst subclasses
+  static CastInst *Create(
+    Instruction::CastOps,    ///< The opcode for the cast instruction
+    Value *S,                ///< The value to be casted (operand 0)
+    const Type *Ty,          ///< The type to which operand is casted
+    const std::string &Name, ///< The name for the instruction
+    BasicBlock *InsertAtEnd  ///< The block to insert the instruction into
+  );
+
+  /// @brief Create a ZExt or BitCast cast instruction
+  static CastInst *CreateZExtOrBitCast(
+    Value *S,                ///< The value to be casted (operand 0)
+    const Type *Ty,          ///< The type to which cast should be made
+    const std::string &Name = "", ///< Name for the instruction
+    Instruction *InsertBefore = 0 ///< Place to insert the instruction
+  );
+
+  /// @brief Create a ZExt or BitCast cast instruction
+  static CastInst *CreateZExtOrBitCast(
+    Value *S,                ///< The value to be casted (operand 0)
+    const Type *Ty,          ///< The type to which operand is casted
+    const std::string &Name, ///< The name for the instruction
+    BasicBlock *InsertAtEnd  ///< The block to insert the instruction into
+  );
+
+  /// @brief Create a SExt or BitCast cast instruction
+  static CastInst *CreateSExtOrBitCast(
+    Value *S,                ///< The value to be casted (operand 0)
+    const Type *Ty,          ///< The type to which cast should be made
+    const std::string &Name = "", ///< Name for the instruction
+    Instruction *InsertBefore = 0 ///< Place to insert the instruction
+  );
+
+  /// @brief Create a SExt or BitCast cast instruction
+  static CastInst *CreateSExtOrBitCast(
+    Value *S,                ///< The value to be casted (operand 0)
+    const Type *Ty,          ///< The type to which operand is casted
+    const std::string &Name, ///< The name for the instruction
+    BasicBlock *InsertAtEnd  ///< The block to insert the instruction into
+  );
+
+  /// @brief Create a BitCast or a PtrToInt cast instruction
+  static CastInst *CreatePointerCast(
+    Value *S,                ///< The pointer value to be casted (operand 0)
+    const Type *Ty,          ///< The type to which operand is casted
+    const std::string &Name, ///< The name for the instruction
+    BasicBlock *InsertAtEnd  ///< The block to insert the instruction into
+  );
+
+  /// @brief Create a BitCast or a PtrToInt cast instruction
+  static CastInst *CreatePointerCast(
+    Value *S,                ///< The pointer value to be casted (operand 0)
+    const Type *Ty,          ///< The type to which cast should be made
+    const std::string &Name = "", ///< Name for the instruction
+    Instruction *InsertBefore = 0 ///< Place to insert the instruction
+  );
+
+  /// @brief Create a ZExt, BitCast, or Trunc for int -> int casts.
+  static CastInst *CreateIntegerCast(
+    Value *S,                ///< The pointer value to be casted (operand 0)
+    const Type *Ty,          ///< The type to which cast should be made
+    bool isSigned,           ///< Whether to regard S as signed or not
+    const std::string &Name = "", ///< Name for the instruction
+    Instruction *InsertBefore = 0 ///< Place to insert the instruction
+  );
+
+  /// @brief Create a ZExt, BitCast, or Trunc for int -> int casts.
+  static CastInst *CreateIntegerCast(
+    Value *S,                ///< The integer value to be casted (operand 0)
+    const Type *Ty,          ///< The integer type to which operand is casted
+    bool isSigned,           ///< Whether to regard S as signed or not
+    const std::string &Name, ///< The name for the instruction
+    BasicBlock *InsertAtEnd  ///< The block to insert the instruction into
+  );
+
+  /// @brief Create an FPExt, BitCast, or FPTrunc for fp -> fp casts
+  static CastInst *CreateFPCast(
+    Value *S,                ///< The floating point value to be casted
+    const Type *Ty,          ///< The floating point type to cast to
+    const std::string &Name = "", ///< Name for the instruction
+    Instruction *InsertBefore = 0 ///< Place to insert the instruction
+  );
+
+  /// @brief Create an FPExt, BitCast, or FPTrunc for fp -> fp casts
+  static CastInst *CreateFPCast(
+    Value *S,                ///< The floating point value to be casted
+    const Type *Ty,          ///< The floating point type to cast to
+    const std::string &Name, ///< The name for the instruction
+    BasicBlock *InsertAtEnd  ///< The block to insert the instruction into
+  );
+
+  /// @brief Create a Trunc or BitCast cast instruction
+  static CastInst *CreateTruncOrBitCast(
+    Value *S,                ///< The value to be casted (operand 0)
+    const Type *Ty,          ///< The type to which cast should be made
+    const std::string &Name = "", ///< Name for the instruction
+    Instruction *InsertBefore = 0 ///< Place to insert the instruction
+  );
+
+  /// @brief Create a Trunc or BitCast cast instruction
+  static CastInst *CreateTruncOrBitCast(
+    Value *S,                ///< The value to be casted (operand 0)
+    const Type *Ty,          ///< The type to which operand is casted
+    const std::string &Name, ///< The name for the instruction
+    BasicBlock *InsertAtEnd  ///< The block to insert the instruction into
+  );
+
+  /// @brief Check whether it is valid to call getCastOpcode for these types.
+  static bool isCastable(
+    const Type *SrcTy, ///< The Type from which the value should be cast.
+    const Type *DestTy ///< The Type to which the value should be cast.
+  );
+
+  /// Returns the opcode necessary to cast Val into Ty using usual casting
+  /// rules.
+  /// @brief Infer the opcode for cast operand and type
+  static Instruction::CastOps getCastOpcode(
+    const Value *Val, ///< The value to cast
+    bool SrcIsSigned, ///< Whether to treat the source as signed
+    const Type *Ty,   ///< The Type to which the value should be casted
+    bool DstIsSigned  ///< Whether to treate the dest. as signed
+  );
+
+  /// There are several places where we need to know if a cast instruction
+  /// only deals with integer source and destination types. To simplify that
+  /// logic, this method is provided.
+  /// @returns true iff the cast has only integral typed operand and dest type.
+  /// @brief Determine if this is an integer-only cast.
+  bool isIntegerCast() const;
+
+  /// A lossless cast is one that does not alter the basic value. It implies
+  /// a no-op cast but is more stringent, preventing things like int->float,
+  /// long->double, int->ptr, or vector->anything.
+  /// @returns true iff the cast is lossless.
+  /// @brief Determine if this is a lossless cast.
+  bool isLosslessCast() const;
+
+  /// A no-op cast is one that can be effected without changing any bits.
+  /// It implies that the source and destination types are the same size. The
+  /// IntPtrTy argument is used to make accurate determinations for casts
+  /// involving Integer and Pointer types. They are no-op casts if the integer
+  /// is the same size as the pointer. However, pointer size varies with
+  /// platform. Generally, the result of TargetData::getIntPtrType() should be
+  /// passed in. If that's not available, use Type::Int64Ty, which will make
+  /// the isNoopCast call conservative.
+  /// @brief Determine if this cast is a no-op cast.
+  bool isNoopCast(
+    const Type *IntPtrTy ///< Integer type corresponding to pointer
+  ) const;
+
+  /// Determine how a pair of casts can be eliminated, if they can be at all.
+  /// This is a helper function for both CastInst and ConstantExpr.
+  /// @returns 0 if the CastInst pair can't be eliminated
+  /// @returns Instruction::CastOps value for a cast that can replace
+  /// the pair, casting SrcTy to DstTy.
+  /// @brief Determine if a cast pair is eliminable
+  static unsigned isEliminableCastPair(
+    Instruction::CastOps firstOpcode,  ///< Opcode of first cast
+    Instruction::CastOps secondOpcode, ///< Opcode of second cast
+    const Type *SrcTy, ///< SrcTy of 1st cast
+    const Type *MidTy, ///< DstTy of 1st cast & SrcTy of 2nd cast
+    const Type *DstTy, ///< DstTy of 2nd cast
+    const Type *IntPtrTy ///< Integer type corresponding to Ptr types
+  );
+
+  /// @brief Return the opcode of this CastInst
+  Instruction::CastOps getOpcode() const {
+    return Instruction::CastOps(Instruction::getOpcode());
+  }
+
+  /// @brief Return the source type, as a convenience
+  const Type* getSrcTy() const { return getOperand(0)->getType(); }
+  /// @brief Return the destination type, as a convenience
+  const Type* getDestTy() const { return getType(); }
+
+  /// This method can be used to determine if a cast from S to DstTy using
+  /// Opcode op is valid or not.
+  /// @returns true iff the proposed cast is valid.
+  /// @brief Determine if a cast is valid without creating one.
+  static bool castIsValid(Instruction::CastOps op, Value *S, const Type *DstTy);
+
+  /// @brief Methods for support type inquiry through isa, cast, and dyn_cast:
+  static inline bool classof(const CastInst *) { return true; }
+  static inline bool classof(const Instruction *I) {
+    return I->isCast();
+  }
+  static inline bool classof(const Value *V) {
+    return isa<Instruction>(V) && classof(cast<Instruction>(V));
+  }
+};
+
+//===----------------------------------------------------------------------===//
+//                               CmpInst Class
+//===----------------------------------------------------------------------===//
+
+/// This class is the base class for the comparison instructions.
+/// @brief Abstract base class of comparison instructions.
+// FIXME: why not derive from BinaryOperator?
+class CmpInst: public Instruction {
+  void *operator new(size_t, unsigned);  // DO NOT IMPLEMENT
+  CmpInst(); // do not implement
+protected:
+  CmpInst(const Type *ty, Instruction::OtherOps op, unsigned short pred,
+          Value *LHS, Value *RHS, const std::string &Name = "",
+          Instruction *InsertBefore = 0);
+
+  CmpInst(const Type *ty, Instruction::OtherOps op, unsigned short pred,
+          Value *LHS, Value *RHS, const std::string &Name,
+          BasicBlock *InsertAtEnd);
+
+public:
+  /// This enumeration lists the possible predicates for CmpInst subclasses.
+  /// Values in the range 0-31 are reserved for FCmpInst, while values in the
+  /// range 32-64 are reserved for ICmpInst. This is necessary to ensure the
+  /// predicate values are not overlapping between the classes.
+  enum Predicate {
+    // Opcode             U L G E    Intuitive operation
+    FCMP_FALSE =  0,  /// 0 0 0 0    Always false (always folded)
+    FCMP_OEQ   =  1,  /// 0 0 0 1    True if ordered and equal
+    FCMP_OGT   =  2,  /// 0 0 1 0    True if ordered and greater than
+    FCMP_OGE   =  3,  /// 0 0 1 1    True if ordered and greater than or equal
+    FCMP_OLT   =  4,  /// 0 1 0 0    True if ordered and less than
+    FCMP_OLE   =  5,  /// 0 1 0 1    True if ordered and less than or equal
+    FCMP_ONE   =  6,  /// 0 1 1 0    True if ordered and operands are unequal
+    FCMP_ORD   =  7,  /// 0 1 1 1    True if ordered (no nans)
+    FCMP_UNO   =  8,  /// 1 0 0 0    True if unordered: isnan(X) | isnan(Y)
+    FCMP_UEQ   =  9,  /// 1 0 0 1    True if unordered or equal
+    FCMP_UGT   = 10,  /// 1 0 1 0    True if unordered or greater than
+    FCMP_UGE   = 11,  /// 1 0 1 1    True if unordered, greater than, or equal
+    FCMP_ULT   = 12,  /// 1 1 0 0    True if unordered or less than
+    FCMP_ULE   = 13,  /// 1 1 0 1    True if unordered, less than, or equal
+    FCMP_UNE   = 14,  /// 1 1 1 0    True if unordered or not equal
+    FCMP_TRUE  = 15,  /// 1 1 1 1    Always true (always folded)
+    FIRST_FCMP_PREDICATE = FCMP_FALSE,
+    LAST_FCMP_PREDICATE = FCMP_TRUE,
+    BAD_FCMP_PREDICATE = FCMP_TRUE + 1,
+    ICMP_EQ    = 32,  /// equal
+    ICMP_NE    = 33,  /// not equal
+    ICMP_UGT   = 34,  /// unsigned greater than
+    ICMP_UGE   = 35,  /// unsigned greater or equal
+    ICMP_ULT   = 36,  /// unsigned less than
+    ICMP_ULE   = 37,  /// unsigned less or equal
+    ICMP_SGT   = 38,  /// signed greater than
+    ICMP_SGE   = 39,  /// signed greater or equal
+    ICMP_SLT   = 40,  /// signed less than
+    ICMP_SLE   = 41,  /// signed less or equal
+    FIRST_ICMP_PREDICATE = ICMP_EQ,
+    LAST_ICMP_PREDICATE = ICMP_SLE,
+    BAD_ICMP_PREDICATE = ICMP_SLE + 1
+  };
+
+  // allocate space for exactly two operands
+  void *operator new(size_t s) {
+    return User::operator new(s, 2);
+  }
+  /// Construct a compare instruction, given the opcode, the predicate and
+  /// the two operands.  Optionally (if InstBefore is specified) insert the
+  /// instruction into a BasicBlock right before the specified instruction.
+  /// The specified Instruction is allowed to be a dereferenced end iterator.
+  /// @brief Create a CmpInst
+  static CmpInst *Create(LLVMContext &Context, OtherOps Op,
+                         unsigned short predicate, Value *S1,
+                         Value *S2, const std::string &Name = "",
+                         Instruction *InsertBefore = 0);
+
+  /// Construct a compare instruction, given the opcode, the predicate and the
+  /// two operands.  Also automatically insert this instruction to the end of
+  /// the BasicBlock specified.
+  /// @brief Create a CmpInst
+  static CmpInst *Create(OtherOps Op, unsigned short predicate, Value *S1,
+                         Value *S2, const std::string &Name,
+                         BasicBlock *InsertAtEnd);
+
+  /// @brief Get the opcode casted to the right type
+  OtherOps getOpcode() const {
+    return static_cast<OtherOps>(Instruction::getOpcode());
+  }
+
+  /// @brief Return the predicate for this instruction.
+  Predicate getPredicate() const { return Predicate(SubclassData); }
+
+  /// @brief Set the predicate for this instruction to the specified value.
+  void setPredicate(Predicate P) { SubclassData = P; }
+
+  /// For example, EQ -> NE, UGT -> ULE, SLT -> SGE,
+  ///              OEQ -> UNE, UGT -> OLE, OLT -> UGE, etc.
+  /// @returns the inverse predicate for the instruction's current predicate.
+  /// @brief Return the inverse of the instruction's predicate.
+  Predicate getInversePredicate() const {
+    return getInversePredicate(getPredicate());
+  }
+
+  /// For example, EQ -> NE, UGT -> ULE, SLT -> SGE,
+  ///              OEQ -> UNE, UGT -> OLE, OLT -> UGE, etc.
+  /// @returns the inverse predicate for predicate provided in \p pred.
+  /// @brief Return the inverse of a given predicate
+  static Predicate getInversePredicate(Predicate pred);
+
+  /// For example, EQ->EQ, SLE->SGE, ULT->UGT,
+  ///              OEQ->OEQ, ULE->UGE, OLT->OGT, etc.
+  /// @returns the predicate that would be the result of exchanging the two
+  /// operands of the CmpInst instruction without changing the result
+  /// produced.
+  /// @brief Return the predicate as if the operands were swapped
+  Predicate getSwappedPredicate() const {
+    return getSwappedPredicate(getPredicate());
+  }
+
+  /// This is a static version that you can use without an instruction
+  /// available.
+  /// @brief Return the predicate as if the operands were swapped.
+  static Predicate getSwappedPredicate(Predicate pred);
+
+  /// @brief Provide more efficient getOperand methods.
+  DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
+
+  /// This is just a convenience that dispatches to the subclasses.
+  /// @brief Swap the operands and adjust predicate accordingly to retain
+  /// the same comparison.
+  void swapOperands();
+
+  /// This is just a convenience that dispatches to the subclasses.
+  /// @brief Determine if this CmpInst is commutative.
+  bool isCommutative();
+
+  /// This is just a convenience that dispatches to the subclasses.
+  /// @brief Determine if this is an equals/not equals predicate.
+  bool isEquality();
+
+  /// @returns true if the predicate is unsigned, false otherwise.
+  /// @brief Determine if the predicate is an unsigned operation.
+  static bool isUnsigned(unsigned short predicate);
+
+  /// @returns true if the predicate is signed, false otherwise.
+  /// @brief Determine if the predicate is an signed operation.
+  static bool isSigned(unsigned short predicate);
+
+  /// @brief Determine if the predicate is an ordered operation.
+  static bool isOrdered(unsigned short predicate);
+
+  /// @brief Determine if the predicate is an unordered operation.
+  static bool isUnordered(unsigned short predicate);
+
+  /// @brief Methods for support type inquiry through isa, cast, and dyn_cast:
+  static inline bool classof(const CmpInst *) { return true; }
+  static inline bool classof(const Instruction *I) {
+    return I->getOpcode() == Instruction::ICmp ||
+           I->getOpcode() == Instruction::FCmp;
+  }
+  static inline bool classof(const Value *V) {
+    return isa<Instruction>(V) && classof(cast<Instruction>(V));
+  }
+};
+
+
+// FIXME: these are redundant if CmpInst < BinaryOperator
+template <>
+struct OperandTraits<CmpInst> : FixedNumOperandTraits<2> {
+};
+
+DEFINE_TRANSPARENT_OPERAND_ACCESSORS(CmpInst, Value)
+
+} // End llvm namespace
+
 #endif