aboutsummaryrefslogtreecommitdiffstats
path: root/common/almalloc.cpp
blob: 71953d8bf51fead0627dc92bd25d2f0df6422e5f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61

#include "config.h"

#include "almalloc.h"

#include <cassert>
#include <cstddef>
#include <cstdlib>
#include <cstring>
#include <memory>
#ifdef HAVE_MALLOC_H
#include <malloc.h>
#endif


gsl::owner<void*> al_malloc(size_t alignment, size_t size)
{
    assert((alignment & (alignment-1)) == 0);
    alignment = std::max(alignment, alignof(std::max_align_t));

#if defined(HAVE_POSIX_MEMALIGN)
    gsl::owner<void*> ret{};
    if(posix_memalign(&ret, alignment, size) == 0)
        return ret;
    return nullptr;
#elif defined(HAVE__ALIGNED_MALLOC)
    return _aligned_malloc(size, alignment);
#else
    size_t total_size{size + alignment-1 + sizeof(void*)};
    void *base{std::malloc(total_size)};
    if(base != nullptr)
    {
        void *aligned_ptr{static_cast<char*>(base) + sizeof(void*)};
        total_size -= sizeof(void*);

        std::align(alignment, size, aligned_ptr, total_size);
        *(static_cast<void**>(aligned_ptr)-1) = base;
        base = aligned_ptr;
    }
    return base;
#endif
}

gsl::owner<void*> al_calloc(size_t alignment, size_t size)
{
    gsl::owner<void*> ret{al_malloc(alignment, size)};
    if(ret) std::memset(ret, 0, size);
    return ret;
}

void al_free(gsl::owner<void*> ptr) noexcept
{
#if defined(HAVE_POSIX_MEMALIGN)
    std::free(ptr);
#elif defined(HAVE__ALIGNED_MALLOC)
    _aligned_free(ptr);
#else
    if(ptr != nullptr)
        std::free(*(static_cast<gsl::owner<void*>*>(ptr) - 1));
#endif
}