tsan_vector.h revision 2d1fdb26e458c4ddc04155c1d421bced3ba90cd0 
1//===-- tsan_vector.h -------------------------------------------*- 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 is a part of ThreadSanitizer (TSan), a race detector.
11//
12//===----------------------------------------------------------------------===//
13
14// Low-fat STL-like vector container.
15
16#ifndef TSAN_VECTOR_H
17#define TSAN_VECTOR_H
18
19#include "tsan_defs.h"
20#include "tsan_mman.h"
21
22namespace __tsan {
23
24template<typename T>
25class Vector {
26 public:
27  explicit Vector(MBlockType typ)
28      : typ_(typ)
29      , begin_()
30      , end_()
31      , last_() {
32  }
33
34  ~Vector() {
35    if (begin_)
36      internal_free(begin_);
37  }
38
39  void Reset() {
40    if (begin_)
41      internal_free(begin_);
42    begin_ = 0;
43    end_ = 0;
44    last_ = 0;
45  }
46
47  uptr Size() const {
48    return end_ - begin_;
49  }
50
51  T &operator[](uptr i) {
52    DCHECK_LT(i, end_ - begin_);
53    return begin_[i];
54  }
55
56  const T &operator[](uptr i) const {
57    DCHECK_LT(i, end_ - begin_);
58    return begin_[i];
59  }
60
61  T *PushBack() {
62    EnsureSize(Size() + 1);
63    T *p = &end_[-1];
64    internal_memset(p, 0, sizeof(*p));
65    return p;
66  }
67
68  T *PushBack(const T& v) {
69    EnsureSize(Size() + 1);
70    T *p = &end_[-1];
71    internal_memcpy(p, &v, sizeof(*p));
72    return p;
73  }
74
75  void PopBack() {
76    DCHECK_GT(end_, begin_);
77    end_--;
78  }
79
80  void Resize(uptr size) {
81    uptr old_size = Size();
82    EnsureSize(size);
83    if (old_size < size) {
84      for (uptr i = old_size; i < size; i++)
85        internal_memset(&begin_[i], 0, sizeof(begin_[i]));
86    }
87  }
88
89 private:
90  const MBlockType typ_;
91  T *begin_;
92  T *end_;
93  T *last_;
94
95  void EnsureSize(uptr size) {
96    if (size <= Size())
97      return;
98    if (size <= (uptr)(last_ - begin_)) {
99      end_ = begin_ + size;
100      return;
101    }
102    uptr cap0 = last_ - begin_;
103    uptr cap = 2 * cap0;
104    if (cap == 0)
105      cap = 16;
106    if (cap < size)
107      cap = size;
108    T *p = (T*)internal_alloc(typ_, cap * sizeof(T));
109    if (cap0) {
110      internal_memcpy(p, begin_, cap0 * sizeof(T));
111      internal_free(begin_);
112    }
113    begin_ = p;
114    end_ = begin_ + size;
115    last_ = begin_ + cap;
116  }
117
118  Vector(const Vector&);
119  void operator=(const Vector&);
120};
121}  // namespace __tsan
122
123#endif  // #ifndef TSAN_VECTOR_H
124