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(T v = T()) {
62    EnsureSize(Size() + 1);
63    end_[-1] = v;
64    return &end_[-1];
65  }
66
67  void Resize(uptr size) {
68    uptr old_size = Size();
69    EnsureSize(size);
70    if (old_size < size) {
71      for (uptr i = old_size; i < size; i++)
72        begin_[i] = T();
73    }
74  }
75
76 private:
77  const MBlockType typ_;
78  T *begin_;
79  T *end_;
80  T *last_;
81
82  void EnsureSize(uptr size) {
83    if (size <= Size())
84      return;
85    if (size <= (uptr)(last_ - begin_)) {
86      end_ = begin_ + size;
87      return;
88    }
89    uptr cap0 = last_ - begin_;
90    uptr cap = 2 * cap0;
91    if (cap == 0)
92      cap = 16;
93    if (cap < size)
94      cap = size;
95    T *p = (T*)internal_alloc(typ_, cap * sizeof(T));
96    if (cap0) {
97      internal_memcpy(p, begin_, cap0 * sizeof(T));
98      internal_free(begin_);
99    }
100    begin_ = p;
101    end_ = begin_ + size;
102    last_ = begin_ + cap;
103  }
104
105  Vector(const Vector&);
106  void operator=(const Vector&);
107};
108}
109
110#endif  // #ifndef TSAN_VECTOR_H
111