1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include "base/memory/aligned_memory.h"
6
7#include "base/logging.h"
8
9#if defined(OS_ANDROID)
10#include <malloc.h>
11#endif
12
13namespace base {
14
15void* AlignedAlloc(size_t size, size_t alignment) {
16  DCHECK_GT(size, 0U);
17  DCHECK_EQ(alignment & (alignment - 1), 0U);
18  DCHECK_EQ(alignment % sizeof(void*), 0U);
19  void* ptr = NULL;
20#if defined(COMPILER_MSVC)
21  ptr = _aligned_malloc(size, alignment);
22// Android technically supports posix_memalign(), but does not expose it in
23// the current version of the library headers used by Chrome.  Luckily,
24// memalign() on Android returns pointers which can safely be used with
25// free(), so we can use it instead.  Issue filed to document this:
26// http://code.google.com/p/android/issues/detail?id=35391
27#elif defined(OS_ANDROID)
28  ptr = memalign(alignment, size);
29#else
30  if (posix_memalign(&ptr, alignment, size))
31    ptr = NULL;
32#endif
33  // Since aligned allocations may fail for non-memory related reasons, force a
34  // crash if we encounter a failed allocation; maintaining consistent behavior
35  // with a normal allocation failure in Chrome.
36  if (!ptr) {
37    DLOG(ERROR) << "If you crashed here, your aligned allocation is incorrect: "
38                << "size=" << size << ", alignment=" << alignment;
39    CHECK(false);
40  }
41  // Sanity check alignment just to be safe.
42  DCHECK_EQ(reinterpret_cast<uintptr_t>(ptr) & (alignment - 1), 0U);
43  return ptr;
44}
45
46}  // namespace base
47