1 files changed, 152 insertions, 0 deletions

diff --git a/Objects/methodobject.c b/Objects/methodobject.c
index 946357f24a..c2001f0169 100644
--- a/Objects/methodobject.c
+++ b/Objects/methodobject.c
@@ -97,6 +97,11 @@ PyCFunction_Call(PyObject *func, PyObject *args, PyObject *kwds)
     if (flags == (METH_VARARGS | METH_KEYWORDS)) {
         res = (*(PyCFunctionWithKeywords)meth)(self, args, kwds);
     }
+    else if (flags == METH_FASTCALL) {
+        PyObject **stack = &PyTuple_GET_ITEM(args, 0);
+        Py_ssize_t nargs = PyTuple_GET_SIZE(args);
+        res = _PyCFunction_FastCallDict(func, stack, nargs, kwds);
+    }
     else {
         if (kwds != NULL && PyDict_Size(kwds) != 0) {
             PyErr_Format(PyExc_TypeError, "%.200s() takes no keyword arguments",
@@ -145,6 +150,153 @@ PyCFunction_Call(PyObject *func, PyObject *args, PyObject *kwds)
     return _Py_CheckFunctionResult(func, res, NULL);
 }
 
+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);
+    PyObject *result;
+    int flags;
+
+    assert(PyCFunction_Check(func));
+    assert(func != NULL);
+    assert(nargs >= 0);
+    assert(nargs == 0 || args != NULL);
+    assert(kwargs == NULL || PyDict_Check(kwargs));
+
+    /* _PyCFunction_FastCallDict() must not be called with an exception set,
+       because it may clear it (directly or indirectly) and so the
+       caller loses its exception */
+    assert(!PyErr_Occurred());
+
+    flags = PyCFunction_GET_FLAGS(func) & ~(METH_CLASS | METH_STATIC | METH_COEXIST);
+
+    switch (flags)
+    {
+    case METH_NOARGS:
+        if (kwargs != NULL && PyDict_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_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)",
+                func->m_ml->ml_name, nargs);
+            return NULL;
+        }
+
+        result = (*meth) (self, args[0]);
+        break;
+
+    case METH_VARARGS:
+    case METH_VARARGS | METH_KEYWORDS:
+    {
+        /* Slow-path: create a temporary tuple */
+        PyObject *tuple;
+
+        if (!(flags & METH_KEYWORDS) && kwargs != NULL && PyDict_Size(kwargs) != 0) {
+            PyErr_Format(PyExc_TypeError,
+                         "%.200s() takes no keyword arguments",
+                         func->m_ml->ml_name);
+            return NULL;
+        }
+
+        tuple = _PyStack_AsTuple(args, nargs);
+        if (tuple == NULL) {
+            return NULL;
+        }
+
+        if (flags & METH_KEYWORDS) {
+            result = (*(PyCFunctionWithKeywords)meth) (self, tuple, kwargs);
+        }
+        else {
+            result = (*meth) (self, tuple);
+        }
+        Py_DECREF(tuple);
+        break;
+    }
+
+    case METH_FASTCALL:
+    {
+        PyObject **stack;
+        PyObject *kwnames;
+        _PyCFunctionFast fastmeth = (_PyCFunctionFast)meth;
+
+        stack = _PyStack_UnpackDict(args, nargs, kwargs, &kwnames, func_obj);
+        if (stack == NULL) {
+            return NULL;
+        }
+
+        result = (*fastmeth) (self, stack, nargs, kwnames);
+        if (stack != args) {
+            PyMem_Free(stack);
+        }
+        Py_XDECREF(kwnames);
+        break;
+    }
+
+    default:
+        PyErr_SetString(PyExc_SystemError,
+                        "Bad call flags in PyCFunction_Call. "
+                        "METH_OLDARGS is no longer supported!");
+        return NULL;
+    }
+
+    result = _Py_CheckFunctionResult(func_obj, result, NULL);
+
+    return result;
+}
+
+PyObject *
+_PyCFunction_FastCallKeywords(PyObject *func, PyObject **stack,
+                              Py_ssize_t nargs, PyObject *kwnames)
+{
+    PyObject *kwdict, *result;
+    Py_ssize_t nkwargs = (kwnames == NULL) ? 0 : PyTuple_GET_SIZE(kwnames);
+
+    assert(PyCFunction_Check(func));
+    assert(nargs >= 0);
+    assert(kwnames == NULL || PyTuple_CheckExact(kwnames));
+    assert((nargs == 0 && nkwargs == 0) || stack != 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) {
+            return NULL;
+        }
+    }
+    else {
+        kwdict = NULL;
+    }
+
+    result = _PyCFunction_FastCallDict(func, stack, nargs, kwdict);
+    Py_XDECREF(kwdict);
+    return result;
+}
+
 /* Methods (the standard built-in methods, that is) */
 
 static void