Divisions-by-two for a positive Py_ssize_t compile more cleanly with >>1 than /2.
diff --git a/Modules/_collectionsmodule.c b/Modules/_collectionsmodule.c
index c1fd8b9..47db46f 100644
--- a/Modules/_collectionsmodule.c
+++ b/Modules/_collectionsmodule.c
@@ -788,7 +788,7 @@
block *rightblock = deque->rightblock;
Py_ssize_t leftindex = deque->leftindex;
Py_ssize_t rightindex = deque->rightindex;
- Py_ssize_t n = Py_SIZE(deque) / 2;
+ Py_ssize_t n = Py_SIZE(deque) >> 1;
Py_ssize_t i;
PyObject *tmp;
diff --git a/Modules/_heapqmodule.c b/Modules/_heapqmodule.c
index c343862..28604af 100644
--- a/Modules/_heapqmodule.c
+++ b/Modules/_heapqmodule.c
@@ -66,7 +66,7 @@
/* Bubble up the smaller child until hitting a leaf. */
arr = _PyList_ITEMS(heap);
- limit = endpos / 2; /* smallest pos that has no child */
+ limit = endpos >> 1; /* smallest pos that has no child */
while (pos < limit) {
/* Set childpos to index of smaller child. */
childpos = 2*pos + 1; /* leftmost child position */
@@ -347,7 +347,7 @@
n is odd = 2*j+1, this is (2*j+1-1)/2 = j so j-1 is the largest,
and that's again n//2-1.
*/
- for (i = n/2 - 1 ; i >= 0 ; i--)
+ for (i = (n >> 1) - 1 ; i >= 0 ; i--)
if (siftup_func((PyListObject *)heap, i))
return NULL;
Py_RETURN_NONE;
@@ -420,7 +420,7 @@
/* Bubble up the smaller child until hitting a leaf. */
arr = _PyList_ITEMS(heap);
- limit = endpos / 2; /* smallest pos that has no child */
+ limit = endpos >> 1; /* smallest pos that has no child */
while (pos < limit) {
/* Set childpos to index of smaller child. */
childpos = 2*pos + 1; /* leftmost child position */