GCC Code Coverage Report
Directory: . Exec Total Coverage
File: src/prop/minisat/mtl/Alloc.h Lines: 45 47 95.7 %
Date: 2021-11-08 Branches: 21 108 19.4 %

Line Exec Source
1
/*****************************************************************************************[Alloc.h]
2
Copyright (c) 2008-2010, Niklas Sorensson
3
4
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
5
associated documentation files (the "Software"), to deal in the Software without restriction,
6
including without limitation the rights to use, copy, modify, merge, publish, distribute,
7
sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
8
furnished to do so, subject to the following conditions:
9
10
The above copyright notice and this permission notice shall be included in all copies or
11
substantial portions of the Software.
12
13
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
14
NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
15
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
16
DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
17
OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
18
**************************************************************************************************/
19
20
21
#ifndef Minisat_Alloc_h
22
#define Minisat_Alloc_h
23
24
#include "base/check.h"
25
#include "prop/minisat/mtl/Vec.h"
26
#include "prop/minisat/mtl/XAlloc.h"
27
28
namespace cvc5 {
29
namespace Minisat {
30
31
//=================================================================================================
32
// Simple Region-based memory allocator:
33
34
template<class T>
35
class RegionAllocator
36
{
37
    T*        memory;
38
    uint32_t  sz;
39
    uint32_t  cap;
40
    uint32_t  wasted_;
41
42
    void capacity(uint32_t min_cap);
43
44
 public:
45
    // TODO: make this a class for better type-checking?
46
    typedef uint32_t Ref;
47
    enum { Ref_Undef = UINT32_MAX };
48
    enum { Unit_Size = sizeof(uint32_t) };
49
50
18402
    explicit RegionAllocator(uint32_t start_cap = 1024*1024) : memory(NULL), sz(0), cap(0), wasted_(0){ capacity(start_cap); }
51
18397
    ~RegionAllocator()
52
    {
53
18397
        if (memory != NULL)
54
15335
            ::free(memory);
55
18397
    }
56
57
58
171097
    uint32_t size      () const      { return sz; }
59
82162
    uint32_t wasted    () const      { return wasted_; }
60
61
    Ref      alloc     (int size);
62
711708
    void     free      (int size)    { wasted_ += size; }
63
64
    // Deref, Load Effective Address (LEA), Inverse of LEA (AEL):
65
656072020
    T& operator[](Ref r)
66
    {
67
656072020
      Assert(r >= 0 && r < sz);
68
656072020
      return memory[r];
69
    }
70
14967526
    const T& operator[](Ref r) const
71
    {
72
14967526
      Assert(r >= 0 && r < sz);
73
14967526
      return memory[r];
74
    }
75
76
5806604
    T* lea(Ref r)
77
    {
78
5806604
      Assert(r >= 0 && r < sz);
79
5806604
      return &memory[r];
80
    }
81
94431
    const T* lea(Ref r) const
82
    {
83
94431
      Assert(r >= 0 && r < sz);
84
94431
      return &memory[r];
85
    }
86
    Ref ael(const T* t)
87
    {
88
      Assert((void*)t >= (void*)&memory[0]
89
             && (void*)t < (void*)&memory[sz - 1]);
90
      return (Ref)(t - &memory[0]);
91
    }
92
93
3060
    void     moveTo(RegionAllocator& to) {
94
3060
        if (to.memory != NULL) ::free(to.memory);
95
3060
        to.memory = memory;
96
3060
        to.sz = sz;
97
3060
        to.cap = cap;
98
3060
        to.wasted_ = wasted_;
99
100
3060
        memory = NULL;
101
3060
        sz = cap = wasted_ = 0;
102
3060
    }
103
104
105
};
106
107
template<class T>
108
5825006
void RegionAllocator<T>::capacity(uint32_t min_cap)
109
{
110
5825006
    if (cap >= min_cap) return;
111
112
21711
    uint32_t prev_cap = cap;
113
931419
    while (cap < min_cap){
114
        // NOTE: Multiply by a factor (13/8) without causing overflow, then add 2 and make the
115
        // result even by clearing the least significant bit. The resulting sequence of capacities
116
        // is carefully chosen to hit a maximum capacity that is close to the '2^32-1' limit when
117
        // using 'uint32_t' as indices so that as much as possible of this space can be used.
118
454854
        uint32_t delta = ((cap >> 1) + (cap >> 3) + 2) & ~1;
119
454854
        cap += delta;
120
121
454854
        if (cap <= prev_cap)
122
            throw OutOfMemoryException();
123
    }
124
    // printf(" .. (%p) cap = %u\n", this, cap);
125
126
21711
    Assert(cap > 0);
127
21711
    memory = (T*)xrealloc(memory, sizeof(T)*cap);
128
}
129
130
131
template<class T>
132
typename RegionAllocator<T>::Ref
133
5806604
RegionAllocator<T>::alloc(int size)
134
{
135
    // printf("ALLOC called (this = %p, size = %d)\n", this, size); fflush(stdout);
136
5806604
    Assert(size > 0);
137
5806604
    capacity(sz + size);
138
139
5806604
    uint32_t prev_sz = sz;
140
5806604
    sz += size;
141
142
    // Handle overflow:
143
5806604
    if (sz < prev_sz)
144
        throw OutOfMemoryException();
145
146
5806604
    return prev_sz;
147
}
148
149
150
//=================================================================================================
151
}
152
}  // namespace cvc5
153
154
#endif