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#include "build/build_config.h"
9
10#if defined(OS_ANDROID)
11#include <malloc.h>
12#endif
13
14namespace base {
15
16void* AlignedAlloc(size_t size, size_t alignment) {
17  DCHECK_GT(size, 0U);
18  DCHECK_EQ(alignment & (alignment - 1), 0U);
19  DCHECK_EQ(alignment % sizeof(void*), 0U);
20  void* ptr = NULL;
21#if defined(COMPILER_MSVC)
22  ptr = _aligned_malloc(size, alignment);
23// Android technically supports posix_memalign(), but does not expose it in
24// the current version of the library headers used by Chrome.  Luckily,
25// memalign() on Android returns pointers which can safely be used with
26// free(), so we can use it instead.  Issue filed to document this:
27// http://code.google.com/p/android/issues/detail?id=35391
28#elif defined(OS_ANDROID)
29  ptr = memalign(alignment, size);
30#else
31  if (posix_memalign(&ptr, alignment, size))
32    ptr = NULL;
33#endif
34  // Since aligned allocations may fail for non-memory related reasons, force a
35  // crash if we encounter a failed allocation; maintaining consistent behavior
36  // with a normal allocation failure in Chrome.
37  if (!ptr) {
38    DLOG(ERROR) << "If you crashed here, your aligned allocation is incorrect: "
39                << "size=" << size << ", alignment=" << alignment;
40    CHECK(false);
41  }
42  // Sanity check alignment just to be safe.
43  DCHECK_EQ(reinterpret_cast<uintptr_t>(ptr) & (alignment - 1), 0U);
44  return ptr;
45}
46
47}  // namespace base
48