LLVM  4.0.0
ilist_iterator.h
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1 //===- llvm/ADT/ilist_iterator.h - Intrusive List Iterator -------*- 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 #ifndef LLVM_ADT_ILIST_ITERATOR_H
11 #define LLVM_ADT_ILIST_ITERATOR_H
12 
13 #include "llvm/ADT/ilist_node.h"
14 #include <cassert>
15 #include <cstddef>
16 #include <iterator>
17 #include <type_traits>
18 
19 namespace llvm {
20 
21 namespace ilist_detail {
22 
23 /// Find const-correct node types.
24 template <class OptionsT, bool IsConst> struct IteratorTraits;
25 template <class OptionsT> struct IteratorTraits<OptionsT, false> {
26  typedef typename OptionsT::value_type value_type;
27  typedef typename OptionsT::pointer pointer;
28  typedef typename OptionsT::reference reference;
31 };
32 template <class OptionsT> struct IteratorTraits<OptionsT, true> {
33  typedef const typename OptionsT::value_type value_type;
34  typedef typename OptionsT::const_pointer pointer;
35  typedef typename OptionsT::const_reference reference;
38 };
39 
40 template <bool IsReverse> struct IteratorHelper;
43  template <class T> static void increment(T *&I) { I = Access::getNext(*I); }
44  template <class T> static void decrement(T *&I) { I = Access::getPrev(*I); }
45 };
48  template <class T> static void increment(T *&I) { I = Access::getPrev(*I); }
49  template <class T> static void decrement(T *&I) { I = Access::getNext(*I); }
50 };
51 
52 } // end namespace ilist_detail
53 
54 /// Iterator for intrusive lists based on ilist_node.
55 template <class OptionsT, bool IsReverse, bool IsConst>
60 
63 
64 public:
65  typedef typename Traits::value_type value_type;
66  typedef typename Traits::pointer pointer;
67  typedef typename Traits::reference reference;
68  typedef ptrdiff_t difference_type;
69  typedef std::bidirectional_iterator_tag iterator_category;
70 
71  typedef typename OptionsT::const_pointer const_pointer;
72  typedef typename OptionsT::const_reference const_reference;
73 
74 private:
75  typedef typename Traits::node_pointer node_pointer;
76  typedef typename Traits::node_reference node_reference;
77 
78  node_pointer NodePtr;
79 
80 public:
81  /// Create from an ilist_node.
82  explicit ilist_iterator(node_reference N) : NodePtr(&N) {}
83 
84  explicit ilist_iterator(pointer NP) : NodePtr(Access::getNodePtr(NP)) {}
85  explicit ilist_iterator(reference NR) : NodePtr(Access::getNodePtr(&NR)) {}
86  ilist_iterator() : NodePtr(nullptr) {}
87 
88  // This is templated so that we can allow constructing a const iterator from
89  // a nonconst iterator...
90  template <bool RHSIsConst>
93  typename std::enable_if<IsConst || !RHSIsConst, void *>::type = nullptr)
94  : NodePtr(RHS.NodePtr) {}
95 
96  // This is templated so that we can allow assigning to a const iterator from
97  // a nonconst iterator...
98  template <bool RHSIsConst>
99  typename std::enable_if<IsConst || !RHSIsConst, ilist_iterator &>::type
101  NodePtr = RHS.NodePtr;
102  return *this;
103  }
104 
105  /// Explicit conversion between forward/reverse iterators.
106  ///
107  /// Translate between forward and reverse iterators without changing range
108  /// boundaries. The resulting iterator will dereference (and have a handle)
109  /// to the previous node, which is somewhat unexpected; but converting the
110  /// two endpoints in a range will give the same range in reverse.
111  ///
112  /// This matches std::reverse_iterator conversions.
113  explicit ilist_iterator(
115  : ilist_iterator(++RHS.getReverse()) {}
116 
117  /// Get a reverse iterator to the same node.
118  ///
119  /// Gives a reverse iterator that will dereference (and have a handle) to the
120  /// same node. Converting the endpoint iterators in a range will give a
121  /// different range; for range operations, use the explicit conversions.
123  if (NodePtr)
126  }
127 
128  /// Const-cast.
130  if (NodePtr)
132  const_cast<typename ilist_iterator<OptionsT, IsReverse,
133  false>::node_reference>(*NodePtr));
135  }
136 
137  // Accessors...
139  assert(!NodePtr->isKnownSentinel());
140  return *Access::getValuePtr(NodePtr);
141  }
142  pointer operator->() const { return &operator*(); }
143 
144  // Comparison operators
145  friend bool operator==(const ilist_iterator &LHS, const ilist_iterator &RHS) {
146  return LHS.NodePtr == RHS.NodePtr;
147  }
148  friend bool operator!=(const ilist_iterator &LHS, const ilist_iterator &RHS) {
149  return LHS.NodePtr != RHS.NodePtr;
150  }
151 
152  // Increment and decrement operators...
154  NodePtr = IsReverse ? NodePtr->getNext() : NodePtr->getPrev();
155  return *this;
156  }
158  NodePtr = IsReverse ? NodePtr->getPrev() : NodePtr->getNext();
159  return *this;
160  }
162  ilist_iterator tmp = *this;
163  --*this;
164  return tmp;
165  }
167  ilist_iterator tmp = *this;
168  ++*this;
169  return tmp;
170  }
171 
172  /// Get the underlying ilist_node.
173  node_pointer getNodePtr() const { return static_cast<node_pointer>(NodePtr); }
174 
175  /// Check for end. Only valid if ilist_sentinel_tracking<true>.
176  bool isEnd() const { return NodePtr ? NodePtr->isSentinel() : false; }
177 };
178 
179 template <typename From> struct simplify_type;
180 
181 /// Allow ilist_iterators to convert into pointers to a node automatically when
182 /// used by the dyn_cast, cast, isa mechanisms...
183 ///
184 /// FIXME: remove this, since there is no implicit conversion to NodeTy.
185 template <class OptionsT, bool IsConst>
186 struct simplify_type<ilist_iterator<OptionsT, false, IsConst>> {
188  typedef typename iterator::pointer SimpleType;
189 
190  static SimpleType getSimplifiedValue(const iterator &Node) { return &*Node; }
191 };
192 template <class OptionsT, bool IsConst>
193 struct simplify_type<const ilist_iterator<OptionsT, false, IsConst>>
194  : simplify_type<ilist_iterator<OptionsT, false, IsConst>> {};
195 
196 } // end namespace llvm
197 
198 #endif // LLVM_ADT_ILIST_ITERATOR_H
Traits::pointer pointer
ilist_iterator(const ilist_iterator< OptionsT, IsReverse, RHSIsConst > &RHS, typename std::enable_if< IsConst||!RHSIsConst, void * >::type=nullptr)
ilist_iterator(node_reference N)
Create from an ilist_node.
node_pointer getNodePtr() const
Get the underlying ilist_node.
ilist_iterator< OptionsT,!IsReverse, IsConst > getReverse() const
Get a reverse iterator to the same node.
bool isEnd() const
Check for end. Only valid if ilist_sentinel_tracking<true>.
static pointer getValuePtr(node_type *N)
Definition: ilist_node.h:213
ilist_iterator< OptionsT, IsReverse, false > getNonConst() const
Const-cast.
Implementation for an ilist node.
Definition: ilist_node.h:41
const ilist_node_impl< OptionsT > * node_pointer
pointer operator->() const
ilist_iterator(reference NR)
Function Alias Analysis false
friend bool operator==(const ilist_iterator &LHS, const ilist_iterator &RHS)
std::enable_if< IsConst||!RHSIsConst, ilist_iterator & >::type operator=(const ilist_iterator< OptionsT, IsReverse, RHSIsConst > &RHS)
OptionsT::const_pointer const_pointer
static SimpleType getSimplifiedValue(const iterator &Node)
const ilist_node_impl< OptionsT > & node_reference
ilist_iterator operator++(int)
ilist_iterator(pointer NP)
Find const-correct node types.
An access class for ilist_node private API.
Definition: ilist_node.h:160
reference operator*() const
Iterator for intrusive lists based on ilist_node.
OptionsT::const_reference const_reference
Traits::value_type value_type
friend bool operator!=(const ilist_iterator &LHS, const ilist_iterator &RHS)
ilist_iterator & operator++()
Basic Alias true
ilist_iterator(const ilist_iterator< OptionsT,!IsReverse, IsConst > &RHS)
Explicit conversion between forward/reverse iterators.
ilist_iterator operator--(int)
ilist_iterator & operator--()
Traits::reference reference
std::bidirectional_iterator_tag iterator_category
#define I(x, y, z)
Definition: MD5.cpp:54
#define N
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
aarch64 promote const