comparison mercurial/parsers.c @ 16786:2631cd5dd244

revlog: switch to a C version of headrevs

The C implementation is more than 100 times faster than the Python
version (which is still available as a fallback).

In a repo with 330,000 revs and a stale .hg/cache/tags file, this
patch improves the performance of "hg tip" from 2.2 to 1.6 seconds.

16785:1dc08dc63c09

bail:
	Py_XDECREF(obj);
	return NULL;
}

static inline int nt_level(const char *node, Py_ssize_t level)
{
	int v = node[level>>1];
	if (!(level & 1))
		v >>= 4;

static PyMethodDef index_methods[] = {
	{"clearcaches", (PyCFunction)index_clearcaches, METH_NOARGS,
	 "clear the index caches"},
	{"get", (PyCFunction)index_m_get, METH_VARARGS,
	 "get an index entry"},
	{"insert", (PyCFunction)index_insert, METH_VARARGS,
	 "insert an index entry"},
	{"partialmatch", (PyCFunction)index_partialmatch, METH_VARARGS,
	 "match a potentially ambiguous node ID"},
	{"stats", (PyCFunction)index_stats, METH_NOARGS,

16786:2631cd5dd244

bail:
	Py_XDECREF(obj);
	return NULL;
}

static PyObject *index_headrevs(indexObject *self)
{
	Py_ssize_t i, len, addlen;
	char *nothead = NULL;
	PyObject *heads;

	len = index_length(self) - 1;
	heads = PyList_New(0);
	if (heads == NULL)
		goto bail;
	if (len == 0) {
		PyObject *nullid = PyInt_FromLong(-1);
		if (nullid == NULL || PyList_Append(heads, nullid) == -1) {
			Py_XDECREF(nullid);
			goto bail;
		}
		goto done;
	}

	nothead = calloc(len, 1);
	if (nothead == NULL)
		goto bail;

	for (i = 0; i < self->raw_length; i++) {
		const char *data = index_deref(self, i);
		int parent_1 = getbe32(data + 24);
		int parent_2 = getbe32(data + 28);
		if (parent_1 >= 0)
			nothead[parent_1] = 1;
		if (parent_2 >= 0)
			nothead[parent_2] = 1;
	}

	addlen = self->added ? PyList_GET_SIZE(self->added) : 0;

	for (i = 0; i < addlen; i++) {
		PyObject *rev = PyList_GET_ITEM(self->added, i);
		PyObject *p1 = PyTuple_GET_ITEM(rev, 5);
		PyObject *p2 = PyTuple_GET_ITEM(rev, 6);
		long parent_1, parent_2;

		if (!PyInt_Check(p1) || !PyInt_Check(p2)) {
			PyErr_SetString(PyExc_TypeError,
					"revlog parents are invalid");
			goto bail;
		}
		parent_1 = PyInt_AS_LONG(p1);
		parent_2 = PyInt_AS_LONG(p2);
		if (parent_1 >= 0)
			nothead[parent_1] = 1;
		if (parent_2 >= 0)
			nothead[parent_2] = 1;
	}

	for (i = 0; i < len; i++) {
		PyObject *head;

		if (nothead[i])
			continue;
		head = PyInt_FromLong(i);
		if (head == NULL || PyList_Append(heads, head) == -1) {
			Py_XDECREF(head);
			goto bail;
		}
	}

done:
	free(nothead);
	return heads;
bail:
	Py_XDECREF(heads);
	free(nothead);
	return NULL;
}

static inline int nt_level(const char *node, Py_ssize_t level)
{
	int v = node[level>>1];
	if (!(level & 1))
		v >>= 4;

static PyMethodDef index_methods[] = {
	{"clearcaches", (PyCFunction)index_clearcaches, METH_NOARGS,
	 "clear the index caches"},
	{"get", (PyCFunction)index_m_get, METH_VARARGS,
	 "get an index entry"},
	{"headrevs", (PyCFunction)index_headrevs, METH_NOARGS,
	 "get head revisions"},
	{"insert", (PyCFunction)index_insert, METH_VARARGS,
	 "insert an index entry"},
	{"partialmatch", (PyCFunction)index_partialmatch, METH_VARARGS,
	 "match a potentially ambiguous node ID"},
	{"stats", (PyCFunction)index_stats, METH_NOARGS,