mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-07-16 15:55:18 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 8

bpo-41756: Introduce PyGen_Send C API (GH-22196)

Browse source 
The new API allows to efficiently send values into native generators
and coroutines avoiding use of StopIteration exceptions to signal 
returns.

ceval loop now uses this method instead of the old "private"
_PyGen_Send C API. This translates to 1.6x increased performance
of 'await' calls in micro-benchmarks.

Aside from CPython core improvements, this new API will also allow 
Cython to generate more efficient code, benefiting high-performance
IO libraries like uvloop.
This commit is contained in:
Vladimir Matveev 2020-09-18 18:38:38 -07:00 • committed by GitHub
parent ec8a15b034
commit 2b05361bf7
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
7 changed files with 148 additions and 39 deletions
Download patch file Download diff file Expand all files Collapse all files

58
Python/ceval.c
View file

@ -2223,29 +2223,53 @@ main_loop:
case TARGET(YIELD_FROM): {
PyObject *v = POP();
PyObject *receiver = TOP();
int err;
if (PyGen_CheckExact(receiver) || PyCoro_CheckExact(receiver)) {
retval = _PyGen_Send((PyGenObject *)receiver, v);
int is_gen_or_coro = PyGen_CheckExact(receiver) || PyCoro_CheckExact(receiver);
int gen_status;
if (tstate->c_tracefunc == NULL && is_gen_or_coro) {
gen_status = PyGen_Send((PyGenObject *)receiver, v, &retval);
} else {
_Py_IDENTIFIER(send);
if (v == Py_None)
retval = Py_TYPE(receiver)->tp_iternext(receiver);
else
retval = _PyObject_CallMethodIdOneArg(receiver, &PyId_send, v);
if (is_gen_or_coro) {
retval = _PyGen_Send((PyGenObject *)receiver, v);
}
else {
_Py_IDENTIFIER(send);
if (v == Py_None) {
retval = Py_TYPE(receiver)->tp_iternext(receiver);
}
else {
retval = _PyObject_CallMethodIdOneArg(receiver, &PyId_send, v);
}
}
if (retval == NULL) {
if (tstate->c_tracefunc != NULL
&& _PyErr_ExceptionMatches(tstate, PyExc_StopIteration))
call_exc_trace(tstate->c_tracefunc, tstate->c_traceobj, tstate, f);
if (_PyGen_FetchStopIterationValue(&retval) == 0) {
gen_status = PYGEN_RETURN;
}
else {
gen_status = PYGEN_ERROR;
}
}
else {
gen_status = PYGEN_NEXT;
}
}
Py_DECREF(v);
if (retval == NULL) {
PyObject *val;
if (tstate->c_tracefunc != NULL
&& _PyErr_ExceptionMatches(tstate, PyExc_StopIteration))
call_exc_trace(tstate->c_tracefunc, tstate->c_traceobj, tstate, f);
err = _PyGen_FetchStopIterationValue(&val);
if (err < 0)
goto error;
if (gen_status == PYGEN_ERROR) {
assert (retval == NULL);
goto error;
}
if (gen_status == PYGEN_RETURN) {
assert (retval != NULL);
Py_DECREF(receiver);
SET_TOP(val);
SET_TOP(retval);
retval = NULL;
DISPATCH();
}
assert (gen_status == PYGEN_NEXT);
/* receiver remains on stack, retval is value to be yielded */
/* and repeat... */
assert(f->f_lasti >= (int)sizeof(_Py_CODEUNIT));