Optimize _PyCFunction_FastCallKeywords()

Issue #29259: Write fast path in _PyCFunction_FastCallKeywords() for
METH_FASTCALL, avoid the creation of a temporary dictionary for keyword
arguments.

Cleanup also _PyCFunction_FastCallDict():

* Don't dereference func before checking that it's not NULL
* Move code to raise the "no keyword argument" exception into a new
  no_keyword_error label.

Update python-gdb.py for the change.
This commit is contained in:
Victor Stinner 2017-01-16 17:18:53 +01:00
parent 15f94596b6
commit 7fc252adfb
2 changed files with 134 additions and 38 deletions

View File

@ -89,7 +89,7 @@ PyCFunction_Call(PyObject *func, PyObject *args, PyObject *kwds)
assert(kwds == NULL || PyDict_Check(kwds));
/* PyCFunction_Call() must not be called with an exception set,
because it may clear it (directly or indirectly) and so the
because it can clear it (directly or indirectly) and so the
caller loses its exception */
assert(!PyErr_Occurred());
@ -155,14 +155,14 @@ PyObject *
_PyCFunction_FastCallDict(PyObject *func_obj, PyObject **args, Py_ssize_t nargs,
PyObject *kwargs)
{
PyCFunctionObject *func = (PyCFunctionObject*)func_obj;
PyCFunction meth = PyCFunction_GET_FUNCTION(func);
PyObject *self = PyCFunction_GET_SELF(func);
PyCFunctionObject *func;
PyCFunction meth;
PyObject *self;
PyObject *result;
int flags;
assert(PyCFunction_Check(func));
assert(func != NULL);
assert(func_obj != NULL);
assert(PyCFunction_Check(func_obj));
assert(nargs >= 0);
assert(nargs == 0 || args != NULL);
assert(kwargs == NULL || PyDict_Check(kwargs));
@ -172,34 +172,28 @@ _PyCFunction_FastCallDict(PyObject *func_obj, PyObject **args, Py_ssize_t nargs,
caller loses its exception */
assert(!PyErr_Occurred());
func = (PyCFunctionObject*)func_obj;
meth = PyCFunction_GET_FUNCTION(func);
self = PyCFunction_GET_SELF(func);
flags = PyCFunction_GET_FLAGS(func) & ~(METH_CLASS | METH_STATIC | METH_COEXIST);
switch (flags)
{
case METH_NOARGS:
if (nargs != 0) {
goto no_keyword_error;
}
if (kwargs != NULL && PyDict_GET_SIZE(kwargs) != 0) {
PyErr_Format(PyExc_TypeError, "%.200s() takes no keyword arguments",
func->m_ml->ml_name);
return NULL;
}
if (nargs != 0) {
PyErr_Format(PyExc_TypeError,
"%.200s() takes no arguments (%zd given)",
func->m_ml->ml_name, nargs);
return NULL;
}
result = (*meth) (self, NULL);
break;
case METH_O:
if (kwargs != NULL && PyDict_GET_SIZE(kwargs) != 0) {
PyErr_Format(PyExc_TypeError, "%.200s() takes no keyword arguments",
func->m_ml->ml_name);
return NULL;
}
if (nargs != 1) {
PyErr_Format(PyExc_TypeError,
"%.200s() takes exactly one argument (%zd given)",
@ -207,20 +201,22 @@ _PyCFunction_FastCallDict(PyObject *func_obj, PyObject **args, Py_ssize_t nargs,
return NULL;
}
if (kwargs != NULL && PyDict_GET_SIZE(kwargs) != 0) {
goto no_keyword_error;
}
result = (*meth) (self, args[0]);
break;
case METH_VARARGS:
case METH_VARARGS | METH_KEYWORDS:
{
/* Slow-path: create a temporary tuple */
/* Slow-path: create a temporary tuple for positional arguments */
PyObject *tuple;
if (!(flags & METH_KEYWORDS) && kwargs != NULL && PyDict_GET_SIZE(kwargs) != 0) {
PyErr_Format(PyExc_TypeError,
"%.200s() takes no keyword arguments",
func->m_ml->ml_name);
return NULL;
if (!(flags & METH_KEYWORDS)
&& kwargs != NULL && PyDict_GET_SIZE(kwargs) != 0) {
goto no_keyword_error;
}
tuple = _PyStack_AsTuple(args, nargs);
@ -267,35 +263,134 @@ _PyCFunction_FastCallDict(PyObject *func_obj, PyObject **args, Py_ssize_t nargs,
result = _Py_CheckFunctionResult(func_obj, result, NULL);
return result;
no_keyword_error:
PyErr_Format(PyExc_TypeError,
"%.200s() takes no arguments (%zd given)",
func->m_ml->ml_name, nargs);
return NULL;
}
PyObject *
_PyCFunction_FastCallKeywords(PyObject *func, PyObject **stack,
_PyCFunction_FastCallKeywords(PyObject *func_obj, PyObject **args,
Py_ssize_t nargs, PyObject *kwnames)
{
PyObject *kwdict, *result;
PyCFunctionObject *func;
PyCFunction meth;
PyObject *self, *result;
Py_ssize_t nkwargs = (kwnames == NULL) ? 0 : PyTuple_GET_SIZE(kwnames);
int flags;
assert(PyCFunction_Check(func));
assert(func_obj != NULL);
assert(PyCFunction_Check(func_obj));
assert(nargs >= 0);
assert(kwnames == NULL || PyTuple_CheckExact(kwnames));
assert((nargs == 0 && nkwargs == 0) || stack != NULL);
assert((nargs == 0 && nkwargs == 0) || args != NULL);
/* kwnames must only contains str strings, no subclass, and all keys must
be unique */
if (nkwargs > 0) {
kwdict = _PyStack_AsDict(stack + nargs, kwnames);
if (kwdict == NULL) {
/* _PyCFunction_FastCallKeywords() must not be called with an exception
set, because it can clear it (directly or indirectly) and so the caller
loses its exception */
assert(!PyErr_Occurred());
func = (PyCFunctionObject*)func_obj;
meth = PyCFunction_GET_FUNCTION(func);
self = PyCFunction_GET_SELF(func);
flags = PyCFunction_GET_FLAGS(func) & ~(METH_CLASS | METH_STATIC | METH_COEXIST);
switch (flags)
{
case METH_NOARGS:
if (nargs != 0) {
PyErr_Format(PyExc_TypeError,
"%.200s() takes no arguments (%zd given)",
func->m_ml->ml_name, nargs);
return NULL;
}
}
else {
kwdict = NULL;
if (nkwargs) {
goto no_keyword_error;
}
result = (*meth) (self, NULL);
break;
case METH_O:
if (nargs != 1) {
PyErr_Format(PyExc_TypeError,
"%.200s() takes exactly one argument (%zd given)",
func->m_ml->ml_name, nargs);
return NULL;
}
if (nkwargs) {
goto no_keyword_error;
}
result = (*meth) (self, args[0]);
break;
case METH_FASTCALL:
/* Fast-path: avoid temporary dict to pass keyword arguments */
result = ((_PyCFunctionFast)meth) (self, args, nargs, kwnames);
break;
case METH_VARARGS:
case METH_VARARGS | METH_KEYWORDS:
{
/* Slow-path: create a temporary tuple for positional arguments
and a temporary dict for keyword arguments */
PyObject *argtuple;
if (!(flags & METH_KEYWORDS) && nkwargs) {
goto no_keyword_error;
}
argtuple = _PyStack_AsTuple(args, nargs);
if (argtuple == NULL) {
return NULL;
}
if (flags & METH_KEYWORDS) {
PyObject *kwdict;
if (nkwargs > 0) {
kwdict = _PyStack_AsDict(args + nargs, kwnames);
if (kwdict == NULL) {
Py_DECREF(argtuple);
return NULL;
}
}
else {
kwdict = NULL;
}
result = (*(PyCFunctionWithKeywords)meth) (self, argtuple, kwdict);
Py_XDECREF(kwdict);
}
else {
result = (*meth) (self, argtuple);
}
Py_DECREF(argtuple);
break;
}
result = _PyCFunction_FastCallDict(func, stack, nargs, kwdict);
Py_XDECREF(kwdict);
default:
PyErr_SetString(PyExc_SystemError,
"Bad call flags in _PyCFunction_FastCallKeywords. "
"METH_OLDARGS is no longer supported!");
return NULL;
}
result = _Py_CheckFunctionResult(func_obj, result, NULL);
return result;
no_keyword_error:
PyErr_Format(PyExc_TypeError,
"%.200s() takes no keyword arguments",
func->m_ml->ml_name);
return NULL;
}
/* Methods (the standard built-in methods, that is) */

View File

@ -1518,7 +1518,8 @@ class Frame(object):
except RuntimeError:
return 'PyCFunction invocation (unable to read "func")'
elif caller == '_PyCFunction_FastCallDict':
elif caller in {'_PyCFunction_FastCallDict',
'_PyCFunction_FastCallKeywords'}:
try:
func = older._gdbframe.read_var('func_obj')
return str(func)