-//===-- llvm/User.h - User class definition ----------------------*- C++ -*--=//
+//===-- llvm/User.h - User 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 class defines the interface that one who 'use's a Value must implement.
// Each instance of the Value class keeps track of what User's have handles
#include "llvm/Value.h"
+namespace llvm {
+
+/// OperandTraits - Compile-time customization of
+/// operand-related allocators and accessors
+/// for use of the User class
+template <class>
+struct OperandTraits;
+
+class User;
+
+/// OperandTraits<User> - specialization to User
+template <>
+struct OperandTraits<User> {
+ static inline Use *op_begin(User*);
+ static inline Use *op_end(User*);
+ static inline unsigned operands(const User*);
+ template <class U>
+ struct Layout {
+ typedef U overlay;
+ };
+ static inline void *allocate(unsigned);
+};
+
class User : public Value {
User(const User &); // Do not implement
+ void *operator new(size_t); // Do not implement
+ template <unsigned>
+ friend struct HungoffOperandTraits;
protected:
- vector<Use> Operands;
-public:
- User(const Type *Ty, ValueTy vty, const string &name = "");
- virtual ~User() { dropAllReferences(); }
+ /// OperandList - This is a pointer to the array of Users for this operand.
+ /// For nodes of fixed arity (e.g. a binary operator) this array will live
+ /// prefixed to the derived class. For nodes of resizable variable arity
+ /// (e.g. PHINodes, SwitchInst etc.), this memory will be dynamically
+ /// allocated and should be destroyed by the classes'
+ /// virtual dtor.
+ Use *OperandList;
+
+ /// NumOperands - The number of values used by this User.
+ ///
+ unsigned NumOperands;
- inline Value *getOperand(unsigned i) {
- assert(i < Operands.size() && "getOperand() out of range!");
- return Operands[i];
+ void *operator new(size_t s, unsigned Us);
+ User(const Type *ty, unsigned vty, Use *OpList, unsigned NumOps)
+ : Value(ty, vty), OperandList(OpList), NumOperands(NumOps) {}
+ Use *allocHungoffUses(unsigned) const;
+ void dropHungoffUses(Use *U) {
+ if (OperandList == U) {
+ OperandList = 0;
+ NumOperands = 0;
+ }
+ Use::zap(U, U->getImpliedUser(), true);
+ }
+public:
+ ~User() {
+ Use::zap(OperandList, OperandList + NumOperands);
}
- inline const Value *getOperand(unsigned i) const {
- assert(i < Operands.size() && "getOperand() const out of range!");
- return Operands[i];
+ /// operator delete - free memory allocated for User and Use objects
+ void operator delete(void *Usr);
+ /// placement delete - required by std, but never called.
+ void operator delete(void*, unsigned) {
+ assert(0 && "Constructor throws?");
}
- inline void setOperand(unsigned i, Value *Val) {
- assert(i < Operands.size() && "setOperand() out of range!");
- Operands[i] = Val;
+ template <unsigned Idx> Use &Op() {
+ return OperandTraits<User>::op_begin(this)[Idx];
}
- inline unsigned getNumOperands() const { return Operands.size(); }
+ template <unsigned Idx> const Use &Op() const {
+ return OperandTraits<User>::op_begin(const_cast<User*>(this))[Idx];
+ }
+ Value *getOperand(unsigned i) const {
+ assert(i < NumOperands && "getOperand() out of range!");
+ return OperandList[i];
+ }
+ void setOperand(unsigned i, Value *Val) {
+ assert(i < NumOperands && "setOperand() out of range!");
+ OperandList[i] = Val;
+ }
+ unsigned getNumOperands() const { return NumOperands; }
// ---------------------------------------------------------------------------
// Operand Iterator interface...
//
- typedef vector<Use>::iterator op_iterator;
- typedef vector<Use>::const_iterator op_const_iterator;
+ typedef Use* op_iterator;
+ typedef const Use* const_op_iterator;
- inline op_iterator op_begin() { return Operands.begin(); }
- inline op_const_iterator op_begin() const { return Operands.begin(); }
- inline op_iterator op_end() { return Operands.end(); }
- inline op_const_iterator op_end() const { return Operands.end(); }
+ inline op_iterator op_begin() { return OperandList; }
+ inline const_op_iterator op_begin() const { return OperandList; }
+ inline op_iterator op_end() { return OperandList+NumOperands; }
+ inline const_op_iterator op_end() const { return OperandList+NumOperands; }
// dropAllReferences() - This function is in charge of "letting go" of all
// objects that this User refers to. This allows one to
// 'delete' a whole class at a time, even though there may be circular
- // references... first all references are dropped, and all use counts go to
- // zero. Then everything is delete'd for real. Note that no operations are
- // valid on an object that has "dropped all references", except operator
+ // references... First all references are dropped, and all use counts go to
+ // zero. Then everything is deleted for real. Note that no operations are
+ // valid on an object that has "dropped all references", except operator
// delete.
//
- inline void dropAllReferences() {
- Operands.clear();
+ void dropAllReferences() {
+ for (op_iterator i = op_begin(), e = op_end(); i != e; ++i)
+ i->set(0);
}
- // replaceUsesOfWith - Replaces all references to the "From" definition with
- // references to the "To" definition. (defined in Value.cpp)
- //
+ /// replaceUsesOfWith - Replaces all references to the "From" definition with
+ /// references to the "To" definition.
+ ///
void replaceUsesOfWith(Value *From, Value *To);
- // addOperand - This is a special purpose API that should not be used in most
- // cases. It adds an empty (null) operand to the instruction specified. This
- // is currently used by the back end as part of the "lowering" process... most
- // optimizations will not handle instructions that are not in their normal
- // form, so this method should be used with care.
- //
- void addOperand() {
- Operands.push_back(Use(0, this));
+ // Methods for support type inquiry through isa, cast, and dyn_cast:
+ static inline bool classof(const User *) { return true; }
+ static inline bool classof(const Value *V) {
+ return isa<Instruction>(V) || isa<Constant>(V);
}
};
+inline Use *OperandTraits<User>::op_begin(User *U) {
+ return U->op_begin();
+}
+
+inline Use *OperandTraits<User>::op_end(User *U) {
+ return U->op_end();
+}
+
+inline unsigned OperandTraits<User>::operands(const User *U) {
+ return U->getNumOperands();
+}
+
+template<> struct simplify_type<User::op_iterator> {
+ typedef Value* SimpleType;
+
+ static SimpleType getSimplifiedValue(const User::op_iterator &Val) {
+ return static_cast<SimpleType>(Val->get());
+ }
+};
+
+template<> struct simplify_type<const User::op_iterator>
+ : public simplify_type<User::op_iterator> {};
+
+template<> struct simplify_type<User::const_op_iterator> {
+ typedef Value* SimpleType;
+
+ static SimpleType getSimplifiedValue(const User::const_op_iterator &Val) {
+ return static_cast<SimpleType>(Val->get());
+ }
+};
+
+template<> struct simplify_type<const User::const_op_iterator>
+ : public simplify_type<User::const_op_iterator> {};
+
+
+// value_use_iterator::getOperandNo - Requires the definition of the User class.
+template<typename UserTy>
+unsigned value_use_iterator<UserTy>::getOperandNo() const {
+ return U - U->getUser()->op_begin();
+}
+
+} // End llvm namespace
+
#endif