Index: base/memory/aligned_memory.cc |
diff --git a/base/memory/aligned_memory.cc b/base/memory/aligned_memory.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..f88495f06468bcd9a6730199e6beb35f06346f3d |
--- /dev/null |
+++ b/base/memory/aligned_memory.cc |
@@ -0,0 +1,42 @@ |
+// Copyright (c) 2012 The Chromium Authors. All rights reserved. |
+// Use of this source code is governed by a BSD-style license that can be |
+// found in the LICENSE file. |
+ |
+#include "base/memory/aligned_memory.h" |
+ |
+#if defined(OS_ANDROID) || defined(OS_NACL) |
willchan no longer on Chromium
2012/07/23 18:48:45
As per Chromium style guide, please move platform
DaleCurtis
2012/07/23 19:04:27
Done.
|
+#include <malloc.h> |
+#endif |
+ |
+#include "base/logging.h" |
+ |
+namespace base { |
+ |
+void* AlignedAlloc(size_t size, size_t alignment) { |
+ DCHECK_GT(size, 0U); |
+ DCHECK_EQ(alignment & (alignment - 1), 0U); |
+ DCHECK_EQ(alignment % sizeof(void*), 0U); |
+ void* ptr = NULL; |
+#if defined(COMPILER_MSVC) |
+ ptr = _aligned_malloc(size, alignment); |
+// Both Android and NaCl technically support posix_memalign(), but do not expose |
+// it in the current version of the library headers used by Chrome. Luckily, |
+// memalign() on both platforms returns pointers which can safely be used with |
Jeffrey Yasskin
2012/07/23 18:34:40
I've seen too many incorrect claims of this form t
DaleCurtis
2012/07/23 19:04:27
The absolute worst case here is free() silently ac
willchan no longer on Chromium
2012/07/23 19:15:44
AIUI, passing non-malloc'd addresses to free() is
DaleCurtis
2012/07/23 19:32:21
We have confirmation from NaCl and Android that th
|
+// free(), so we can use it instead. |
+#elif defined(OS_ANDROID) || defined(OS_NACL) |
+ ptr = memalign(alignment, size); |
+#else |
+ if (posix_memalign(&ptr, alignment, size)) |
+ ptr = NULL; |
+#endif |
+ // Since aligned allocations may fail for non-memory related reasons, force a |
+ // crash if we encounter a failed allocation; maintaining consistent behavior |
+ // with a normal allocation failure in Chrome. |
+ CHECK(ptr) << "If you crashed here, your aligned allocation is incorrect: " |
willchan no longer on Chromium
2012/07/23 18:48:45
I know Jeffrey asked for more info here, but in or
DaleCurtis
2012/07/23 19:04:27
Done.
|
+ << "size=" << size << ", alignment=" << alignment; |
+ // Sanity check alignment just to be safe. |
+ DCHECK_EQ(reinterpret_cast<uintptr_t>(ptr) & (alignment - 1), 0U); |
+ return ptr; |
+} |
+ |
+} // namespace base |