1//===-- llvm/OperandTraits.h - OperandTraits class definition ---*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines the traits classes that are handy for enforcing the correct
11// layout of various User subclasses. It also provides the means for accessing
12// the operands in the most efficient manner.
13//
14
15#ifndef LLVM_IR_OPERANDTRAITS_H
16#define LLVM_IR_OPERANDTRAITS_H
17
18#include "llvm/IR/User.h"
19
20namespace llvm {
21
22//===----------------------------------------------------------------------===//
23//                          FixedNumOperand Trait Class
24//===----------------------------------------------------------------------===//
25
26/// FixedNumOperandTraits - determine the allocation regime of the Use array
27/// when it is a prefix to the User object, and the number of Use objects is
28/// known at compile time.
29
30template <typename SubClass, unsigned ARITY>
31struct FixedNumOperandTraits {
32  static Use *op_begin(SubClass* U) {
33    return reinterpret_cast<Use*>(U) - ARITY;
34  }
35  static Use *op_end(SubClass* U) {
36    return reinterpret_cast<Use*>(U);
37  }
38  static unsigned operands(const User*) {
39    return ARITY;
40  }
41};
42
43//===----------------------------------------------------------------------===//
44//                          OptionalOperand Trait Class
45//===----------------------------------------------------------------------===//
46
47/// OptionalOperandTraits - when the number of operands may change at runtime.
48/// Naturally it may only decrease, because the allocations may not change.
49
50template <typename SubClass, unsigned ARITY = 1>
51struct OptionalOperandTraits : public FixedNumOperandTraits<SubClass, ARITY> {
52  static unsigned operands(const User *U) {
53    return U->getNumOperands();
54  }
55};
56
57//===----------------------------------------------------------------------===//
58//                          VariadicOperand Trait Class
59//===----------------------------------------------------------------------===//
60
61/// VariadicOperandTraits - determine the allocation regime of the Use array
62/// when it is a prefix to the User object, and the number of Use objects is
63/// only known at allocation time.
64
65template <typename SubClass, unsigned MINARITY = 0>
66struct VariadicOperandTraits {
67  static Use *op_begin(SubClass* U) {
68    return reinterpret_cast<Use*>(U) - static_cast<User*>(U)->getNumOperands();
69  }
70  static Use *op_end(SubClass* U) {
71    return reinterpret_cast<Use*>(U);
72  }
73  static unsigned operands(const User *U) {
74    return U->getNumOperands();
75  }
76};
77
78//===----------------------------------------------------------------------===//
79//                          HungoffOperand Trait Class
80//===----------------------------------------------------------------------===//
81
82/// HungoffOperandTraits - determine the allocation regime of the Use array
83/// when it is not a prefix to the User object, but allocated at an unrelated
84/// heap address.
85/// Assumes that the User subclass that is determined by this traits class
86/// has an OperandList member of type User::op_iterator. [Note: this is now
87/// trivially satisfied, because User has that member for historic reasons.]
88///
89/// This is the traits class that is needed when the Use array must be
90/// resizable.
91
92template <unsigned MINARITY = 1>
93struct HungoffOperandTraits {
94  static Use *op_begin(User* U) {
95    return U->OperandList;
96  }
97  static Use *op_end(User* U) {
98    return U->OperandList + U->getNumOperands();
99  }
100  static unsigned operands(const User *U) {
101    return U->getNumOperands();
102  }
103};
104
105/// Macro for generating in-class operand accessor declarations.
106/// It should only be called in the public section of the interface.
107///
108#define DECLARE_TRANSPARENT_OPERAND_ACCESSORS(VALUECLASS) \
109  public: \
110  inline VALUECLASS *getOperand(unsigned) const; \
111  inline void setOperand(unsigned, VALUECLASS*); \
112  inline op_iterator op_begin(); \
113  inline const_op_iterator op_begin() const; \
114  inline op_iterator op_end(); \
115  inline const_op_iterator op_end() const; \
116  protected: \
117  template <int> inline Use &Op(); \
118  template <int> inline const Use &Op() const; \
119  public: \
120  inline unsigned getNumOperands() const
121
122/// Macro for generating out-of-class operand accessor definitions
123#define DEFINE_TRANSPARENT_OPERAND_ACCESSORS(CLASS, VALUECLASS) \
124CLASS::op_iterator CLASS::op_begin() { \
125  return OperandTraits<CLASS>::op_begin(this); \
126} \
127CLASS::const_op_iterator CLASS::op_begin() const { \
128  return OperandTraits<CLASS>::op_begin(const_cast<CLASS*>(this)); \
129} \
130CLASS::op_iterator CLASS::op_end() { \
131  return OperandTraits<CLASS>::op_end(this); \
132} \
133CLASS::const_op_iterator CLASS::op_end() const { \
134  return OperandTraits<CLASS>::op_end(const_cast<CLASS*>(this)); \
135} \
136VALUECLASS *CLASS::getOperand(unsigned i_nocapture) const { \
137  assert(i_nocapture < OperandTraits<CLASS>::operands(this) \
138         && "getOperand() out of range!"); \
139  return cast_or_null<VALUECLASS>( \
140    OperandTraits<CLASS>::op_begin(const_cast<CLASS*>(this))[i_nocapture].get()); \
141} \
142void CLASS::setOperand(unsigned i_nocapture, VALUECLASS *Val_nocapture) { \
143  assert(i_nocapture < OperandTraits<CLASS>::operands(this) \
144         && "setOperand() out of range!"); \
145  OperandTraits<CLASS>::op_begin(this)[i_nocapture] = Val_nocapture; \
146} \
147unsigned CLASS::getNumOperands() const { \
148  return OperandTraits<CLASS>::operands(this); \
149} \
150template <int Idx_nocapture> Use &CLASS::Op() { \
151  return this->OpFrom<Idx_nocapture>(this); \
152} \
153template <int Idx_nocapture> const Use &CLASS::Op() const { \
154  return this->OpFrom<Idx_nocapture>(this); \
155}
156
157
158} // End llvm namespace
159
160#endif
161