Rewrite SamplingCircularQueue

src/allocation.h

Index: src/allocation.h
diff --git a/src/allocation.h b/src/allocation.h
index 45bde4c4cb07068a05e301d2124990637d82609d..62a336f8990719be10a2eeda09a65474def6480e 100644
--- a/src/allocation.h
+++ b/src/allocation.h
@@ -30,6 +30,21 @@
 
 #include "globals.h"
 
+/* Round up n to be a multiple of sz, where sz is a power of 2. */
+#define ROUND_UP(n, sz) (((n) + ((sz) - 1)) & ~((sz) - 1))
+
+// Specify memory alignment for structs, classes, etc.

[Benedikt Meurer, 2013/08/14 11:38:09]

Please move the ALIGN_AT definition to globals.h, near OFFSET_OF maybe.

[yurys, 2013/08/14 13:19:01]

Done.

+// Use like:
+//   class ALIGN_AT(16) MyClass { ... }
+//   ALIGN_AT(16) int array[4];
+#if defined(_MSC_VER)
+#define ALIGN_AT(byte_alignment) __declspec(align(byte_alignment))
+#elif defined(__GNUC__) || defined(__APPLE__)

[Benedikt Meurer, 2013/08/14 11:38:09]

Why __APPLE__ here? This is actually a compiler thing and therefore unrelated to
the operating system (and there's only GCC and clang on OS X anyway, which both
define __GNUC__).

[yurys, 2013/08/14 13:19:01]

Done. Removed __APPLE__.

+#define ALIGN_AT(byte_alignment) __attribute__((aligned(byte_alignment)))
+#else
+#error "ALIGN_AT is not supported for your compiler"

[Benedikt Meurer, 2013/08/14 11:38:09]

Since the alignment is an optimization, I think it's fine to just #define
ALIGN_AT(x) in this case.

[yurys, 2013/08/14 13:19:01]

Done.

+#endif
+
 namespace v8 {
 namespace internal {