Restore the data block size to 62.
The former block size traded away good fit within cache lines in
order to gain faster division in deque_item(). However, compilers
are getting smarter and can now replace the slow division operation
with a fast integer multiply and right shift. Accordingly, it makes
sense to go back to a size that lets blocks neatly fill entire
cache-lines.
GCC-4.8 and CLANG 4.0 both compute "x // 62" with something
roughly equivalent to "x * 9520900167075897609 >> 69".
diff --git a/Lib/test/test_deque.py b/Lib/test/test_deque.py
index 98b203e..595a0c4 100644
--- a/Lib/test/test_deque.py
+++ b/Lib/test/test_deque.py
@@ -522,7 +522,7 @@
@test_support.cpython_only
def test_sizeof(self):
- BLOCKLEN = 64
+ BLOCKLEN = 62
basesize = test_support.calcobjsize('2P4PlP')
blocksize = struct.calcsize('2P%dP' % BLOCKLEN)
self.assertEqual(object.__sizeof__(deque()), basesize)