diff -r 62438d1b11c7 Objects/longobject.c
--- a/Objects/longobject.c	Fri May 02 23:26:03 2014 +0200
+++ b/Objects/longobject.c	Sat May 03 14:40:57 2014 +0200
@@ -34,6 +34,9 @@ static PyLongObject small_ints[NSMALLNEG
 Py_ssize_t quick_int_allocs, quick_neg_int_allocs;
 #endif
 
+/* Forward declaration */
+static PyObject* long_pow2(Py_ssize_t pow2);
+
 static PyObject *
 get_small_int(sdigit ival)
 {
@@ -3855,6 +3858,16 @@ long_pow(PyObject *v, PyObject *w, PyObj
         }
     }
 
+    if (c == NULL && Py_SIZE(a) == 1 && a->ob_digit[0] == 2) {
+        Py_ssize_t shiftby = PyLong_AsSsize_t((PyObject *)b);
+        if (!(shiftby == -1L && PyErr_Occurred())) {
+            Py_DECREF(a);
+            Py_DECREF(b);
+            return long_pow2(shiftby);
+        } else
+            PyErr_Clear();
+    }
+
     if (c) {
         /* if modulus == 0:
                raise ValueError() */
@@ -4099,6 +4112,31 @@ long_rshift(PyLongObject *a, PyLongObjec
 
 }
 
+/* Compute 2 ** k for k >= 0 */
+static PyObject *
+long_pow2(Py_ssize_t k)
+{
+    PyLongObject *z;
+    Py_ssize_t n, r;
+
+    assert(k >= 0);
+    if (k <= 30) {
+        int pow2 = 1 << (int)k;
+        return PyLong_FromLong(pow2);
+    }
+
+    n = k / PyLong_SHIFT;
+    r = k % PyLong_SHIFT;
+
+    z = _PyLong_New(1 + n);
+    if (z == NULL)
+        return NULL;
+    if (n)
+        memset(z->ob_digit, 0, n * sizeof(z->ob_digit[0]));
+    z->ob_digit[n] = (digit)1 << r;
+    return (PyObject *)z;
+}
+
 static PyObject *
 long_lshift(PyObject *v, PyObject *w)
 {