//===-- llvm/OperandTraits.h - OperandTraits class definition ---*- C++ -*-===//
 
//
 
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 
// See https://llvm.org/LICENSE.txt for license information.
 
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 
//
 
//===----------------------------------------------------------------------===//
 
//
 
// This file defines the traits classes that are handy for enforcing the correct
 
// layout of various User subclasses. It also provides the means for accessing
 
// the operands in the most efficient manner.
 
//
 
 
 
#ifndef LLVM_IR_OPERANDTRAITS_H
 
#define LLVM_IR_OPERANDTRAITS_H
 
 
 
#include "llvm/IR/User.h"
 
 
 
namespace llvm {
 
 
 
//===----------------------------------------------------------------------===//
 
//                          FixedNumOperand Trait Class
 
//===----------------------------------------------------------------------===//
 
 
 
/// FixedNumOperandTraits - determine the allocation regime of the Use array
 
/// when it is a prefix to the User object, and the number of Use objects is
 
/// known at compile time.
 
 
 
template <typename SubClass, unsigned ARITY>
 
struct FixedNumOperandTraits {
 
  static Use *op_begin(SubClass* U) {
 
    static_assert(
 
        !std::is_polymorphic<SubClass>::value,
 
        "adding virtual methods to subclasses of User breaks use lists");
 
    return reinterpret_cast<Use*>(U) - ARITY;
 
  }
 
  static Use *op_end(SubClass* U) {
 
    return reinterpret_cast<Use*>(U);
 
  }
 
  static unsigned operands(const User*) {
 
    return ARITY;
 
  }
 
};
 
 
 
//===----------------------------------------------------------------------===//
 
//                          OptionalOperand Trait Class
 
//===----------------------------------------------------------------------===//
 
 
 
/// OptionalOperandTraits - when the number of operands may change at runtime.
 
/// Naturally it may only decrease, because the allocations may not change.
 
 
 
template <typename SubClass, unsigned ARITY = 1>
 
struct OptionalOperandTraits : public FixedNumOperandTraits<SubClass, ARITY> {
 
  static unsigned operands(const User *U) {
 
    return U->getNumOperands();
 
  }
 
};
 
 
 
//===----------------------------------------------------------------------===//
 
//                          VariadicOperand Trait Class
 
//===----------------------------------------------------------------------===//
 
 
 
/// VariadicOperandTraits - determine the allocation regime of the Use array
 
/// when it is a prefix to the User object, and the number of Use objects is
 
/// only known at allocation time.
 
 
 
template <typename SubClass, unsigned MINARITY = 0>
 
struct VariadicOperandTraits {
 
  static Use *op_begin(SubClass* U) {
 
    static_assert(
 
        !std::is_polymorphic<SubClass>::value,
 
        "adding virtual methods to subclasses of User breaks use lists");
 
    return reinterpret_cast<Use*>(U) - static_cast<User*>(U)->getNumOperands();
 
  }
 
  static Use *op_end(SubClass* U) {
 
    return reinterpret_cast<Use*>(U);
 
  }
 
  static unsigned operands(const User *U) {
 
    return U->getNumOperands();
 
  }
 
};
 
 
 
//===----------------------------------------------------------------------===//
 
//                          HungoffOperand Trait Class
 
//===----------------------------------------------------------------------===//
 
 
 
/// HungoffOperandTraits - determine the allocation regime of the Use array
 
/// when it is not a prefix to the User object, but allocated at an unrelated
 
/// heap address.
 
///
 
/// This is the traits class that is needed when the Use array must be
 
/// resizable.
 
 
 
template <unsigned MINARITY = 1>
 
struct HungoffOperandTraits {
 
  static Use *op_begin(User* U) {
 
    return U->getOperandList();
 
  }
 
  static Use *op_end(User* U) {
 
    return U->getOperandList() + U->getNumOperands();
 
  }
 
  static unsigned operands(const User *U) {
 
    return U->getNumOperands();
 
  }
 
};
 
 
 
/// Macro for generating in-class operand accessor declarations.
 
/// It should only be called in the public section of the interface.
 
///
 
#define DECLARE_TRANSPARENT_OPERAND_ACCESSORS(VALUECLASS) \
 
  public: \
 
  inline VALUECLASS *getOperand(unsigned) const; \
 
  inline void setOperand(unsigned, VALUECLASS*); \
 
  inline op_iterator op_begin(); \
 
  inline const_op_iterator op_begin() const; \
 
  inline op_iterator op_end(); \
 
  inline const_op_iterator op_end() const; \
 
  protected: \
 
  template <int> inline Use &Op(); \
 
  template <int> inline const Use &Op() const; \
 
  public: \
 
  inline unsigned getNumOperands() const
 
 
 
/// Macro for generating out-of-class operand accessor definitions
 
#define DEFINE_TRANSPARENT_OPERAND_ACCESSORS(CLASS, VALUECLASS) \
 
CLASS::op_iterator CLASS::op_begin() { \
 
  return OperandTraits<CLASS>::op_begin(this); \
 
} \
 
CLASS::const_op_iterator CLASS::op_begin() const { \
 
  return OperandTraits<CLASS>::op_begin(const_cast<CLASS*>(this)); \
 
} \
 
CLASS::op_iterator CLASS::op_end() { \
 
  return OperandTraits<CLASS>::op_end(this); \
 
} \
 
CLASS::const_op_iterator CLASS::op_end() const { \
 
  return OperandTraits<CLASS>::op_end(const_cast<CLASS*>(this)); \
 
} \
 
VALUECLASS *CLASS::getOperand(unsigned i_nocapture) const { \
 
  assert(i_nocapture < OperandTraits<CLASS>::operands(this) \
 
         && "getOperand() out of range!"); \
 
  return cast_or_null<VALUECLASS>( \
 
    OperandTraits<CLASS>::op_begin(const_cast<CLASS*>(this))[i_nocapture].get()); \
 
} \
 
void CLASS::setOperand(unsigned i_nocapture, VALUECLASS *Val_nocapture) { \
 
  assert(i_nocapture < OperandTraits<CLASS>::operands(this) \
 
         && "setOperand() out of range!"); \
 
  OperandTraits<CLASS>::op_begin(this)[i_nocapture] = Val_nocapture; \
 
} \
 
unsigned CLASS::getNumOperands() const { \
 
  return OperandTraits<CLASS>::operands(this); \
 
} \
 
template <int Idx_nocapture> Use &CLASS::Op() { \
 
  return this->OpFrom<Idx_nocapture>(this); \
 
} \
 
template <int Idx_nocapture> const Use &CLASS::Op() const { \
 
  return this->OpFrom<Idx_nocapture>(this); \
 
}
 
 
 
 
 
} // End llvm namespace
 
 
 
#endif