Speedup the inner loops for dropwhile(), islice(), ifilter(), and

ifilterfalse().

diff --git a/Modules/itertoolsmodule.c b/Modules/itertoolsmodule.c
index 517975b3675dc2729f9c50557eb6d3be25acbc52..3ad26d5b2cf74c9f1afdeba35e3ae247a8b6d9c8 100644 (file)
--- a/Modules/itertoolsmodule.c
+++ b/Modules/itertoolsmodule.c
@@ -835,10 +835,12 @@ dropwhile_next(dropwhileobject *lz)
        PyObject *item, *good;
        PyObject *it = lz->it;
        long ok;
+       PyObject *(*iternext)(PyObject *);
 
+       assert(PyIter_Check(it));
+       iternext = *it->ob_type->tp_iternext;
        for (;;) {
-               assert(PyIter_Check(it));
-               item = (*it->ob_type->tp_iternext)(it);
+               item = iternext(it);
                if (item == NULL)
                        return NULL;
                if (lz->start == 1)
@@ -1170,10 +1172,12 @@ islice_next(isliceobject *lz)
        PyObject *item;
        PyObject *it = lz->it;
        long oldnext;
+       PyObject *(*iternext)(PyObject *);
 
+       assert(PyIter_Check(it));
+       iternext = *it->ob_type->tp_iternext;
        while (lz->cnt < lz->next) {
-               assert(PyIter_Check(it));
-               item = (*it->ob_type->tp_iternext)(it);
+               item = iternext(it);
                if (item == NULL)
                        return NULL;
                Py_DECREF(item);
@@ -1182,7 +1186,7 @@ islice_next(isliceobject *lz)
        if (lz->stop != -1 && lz->cnt >= lz->stop)
                return NULL;
        assert(PyIter_Check(it));
-       item = (*it->ob_type->tp_iternext)(it);
+       item = iternext(it);
        if (item == NULL)
                return NULL;
        lz->cnt++;
@@ -1783,10 +1787,12 @@ ifilter_next(ifilterobject *lz)
        PyObject *item;
        PyObject *it = lz->it;
        long ok;
+       PyObject *(*iternext)(PyObject *);
 
+       assert(PyIter_Check(it));
+       iternext = *it->ob_type->tp_iternext;
        for (;;) {
-               assert(PyIter_Check(it));
-               item = (*it->ob_type->tp_iternext)(it);
+               item = iternext(it);
                if (item == NULL)
                        return NULL;
 
@@ -1932,10 +1938,12 @@ ifilterfalse_next(ifilterfalseobject *lz)
        PyObject *item;
        PyObject *it = lz->it;
        long ok;
+       PyObject *(*iternext)(PyObject *);
 
+       assert(PyIter_Check(it));
+       iternext = *it->ob_type->tp_iternext;
        for (;;) {
-               assert(PyIter_Check(it));
-               item = (*it->ob_type->tp_iternext)(it);
+               item = iternext(it);
                if (item == NULL)
                        return NULL;