[Python-checkins] python/dist/src/Objects listobject.c,2.200,2.201

[rhettinger at users.sourceforge.net]

Update of /cvsroot/python/python/dist/src/Objects
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv16419

Modified Files:
	listobject.c 
Log Message:
* Specialize ins1() into app1() for appends.  Saves several unnecessary
  steps and further improves the speed of list append.

* Add guards to the list iterator length method to handle corner cases.
 


Index: listobject.c
===================================================================
RCS file: /cvsroot/python/python/dist/src/Objects/listobject.c,v
retrieving revision 2.200
retrieving revision 2.201
diff -C2 -d -r2.200 -r2.201
*** listobject.c	20 Mar 2004 22:19:23 -0000	2.200
--- listobject.c	12 Apr 2004 13:05:09 -0000	2.201
***************
*** 181,184 ****
--- 181,204 ----
  }
  
+ static int
+ app1(PyListObject *self, PyObject *v)
+ {
+ 	int n = PyList_GET_SIZE(self);
+ 
+ 	assert (v != NULL);
+ 	if (n == INT_MAX) {
+ 		PyErr_SetString(PyExc_OverflowError,
+ 			"cannot add more objects to list");
+ 		return -1;
+ 	}
+ 
+ 	if (list_resize(self, n+1) == -1)
+ 		return -1;
+ 
+ 	Py_INCREF(v);
+ 	PyList_SET_ITEM(self, n, v);
+ 	return 0;
+ }
+ 
  int
  PyList_Append(PyObject *op, PyObject *newitem)
***************
*** 188,193 ****
  		return -1;
  	}
! 	return ins1((PyListObject *)op,
! 		(int) ((PyListObject *)op)->ob_size, newitem);
  }
  
--- 208,216 ----
  		return -1;
  	}
! 	if (newitem == NULL) {
! 		PyErr_BadInternalCall();
! 		return -1;
! 	}
! 	return app1((PyListObject *)op, newitem);
  }
  
***************
*** 727,731 ****
  			PyList_SET_ITEM(self, i, item); /* steals ref */
  		else {
! 			int status = ins1(self, self->ob_size, item);
  			Py_DECREF(item);  /* append creates a new ref */
  			if (status < 0)
--- 750,754 ----
  			PyList_SET_ITEM(self, i, item); /* steals ref */
  		else {
! 			int status = app1(self, item);
  			Py_DECREF(item);  /* append creates a new ref */
  			if (status < 0)
***************
*** 2685,2690 ****
  listiter_len(listiterobject *it)
  {
! 	if (it->it_seq)
! 		return PyList_GET_SIZE(it->it_seq) - it->it_index;
  	return 0;
  }
--- 2708,2717 ----
  listiter_len(listiterobject *it)
  {
! 	int len;
! 	if (it->it_seq) {
! 		len = PyList_GET_SIZE(it->it_seq) - it->it_index;
! 		if (len >= 0)
! 			return len;
! 	}
  	return 0;
  }
***************
*** 2800,2804 ****
  listreviter_len(listreviterobject *it)
  {
! 	return it->it_index + 1;
  }
  
--- 2827,2834 ----
  listreviter_len(listreviterobject *it)
  {
! 	int len = it->it_index + 1;
! 	if (it->it_seq == NULL || PyList_GET_SIZE(it->it_seq) < len)
! 		return 0;
! 	return len;
  }