diff -r 62438d1b11c7 Objects/longobject.c
--- a/Objects/longobject.c	Fri May 02 23:26:03 2014 +0200
+++ b/Objects/longobject.c	Fri May 02 23:50:54 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_lshift(PyObject *v, PyObject *w);
+
 static PyObject *
 get_small_int(sdigit ival)
 {
@@ -3855,6 +3858,21 @@ long_pow(PyObject *v, PyObject *w, PyObj
         }
     }
 
+    if (c == NULL && Py_SIZE(a) == 1 && a->ob_digit[0] == 2) {
+        PyObject *one, *pow2;
+        one = PyLong_FromLong(1L);
+        if (one == NULL) {
+            Py_DECREF(a);
+            Py_DECREF(b);
+            return NULL;
+        }
+        pow2 = long_lshift(one, w);
+        Py_DECREF(a);
+        Py_DECREF(b);
+        Py_DECREF(one);
+        return pow2;
+    }
+
     if (c) {
         /* if modulus == 0:
                raise ValueError() */
@@ -4118,6 +4136,12 @@ long_lshift(PyObject *v, PyObject *w)
         PyErr_SetString(PyExc_ValueError, "negative shift count");
         return NULL;
     }
+    if (shiftby == 0) {
+        /* x << 0 = x */
+        Py_INCREF(v);
+        return v;
+    }
+
     /* wordshift, remshift = divmod(shiftby, PyLong_SHIFT) */
     wordshift = shiftby / PyLong_SHIFT;
     remshift  = shiftby - wordshift * PyLong_SHIFT;