GH-117224: Move the body of a few large-ish micro-ops into helper functions (GH-122601)

Python/ceval.c

@@ -720,6 +720,7 @@ _PyObjectArray_Free(PyObject **array, PyObject **scratch)
     }
 }
 
+
 /* _PyEval_EvalFrameDefault() is a *big* function,
  * so consume 3 units of C stack */
 #define PY_EVAL_C_STACK_UNITS 2
@@ -3031,3 +3032,137 @@ void Py_LeaveRecursiveCall(void)
 {
     _Py_LeaveRecursiveCall();
 }
+
+PyObject *
+_PyEval_GetANext(PyObject *aiter)
+{
+    unaryfunc getter = NULL;
+    PyObject *next_iter = NULL;
+    PyTypeObject *type = Py_TYPE(aiter);
+    if (PyAsyncGen_CheckExact(aiter)) {
+        return type->tp_as_async->am_anext(aiter);
+    }
+    if (type->tp_as_async != NULL){
+        getter = type->tp_as_async->am_anext;
+    }
+
+    if (getter != NULL) {
+        next_iter = (*getter)(aiter);
+        if (next_iter == NULL) {
+            return NULL;
+        }
+    }
+    else {
+        PyErr_Format(PyExc_TypeError,
+                        "'async for' requires an iterator with "
+                        "__anext__ method, got %.100s",
+                        type->tp_name);
+        return NULL;
+    }
+
+    PyObject *awaitable = _PyCoro_GetAwaitableIter(next_iter);
+    if (awaitable == NULL) {
+        _PyErr_FormatFromCause(
+            PyExc_TypeError,
+            "'async for' received an invalid object "
+            "from __anext__: %.100s",
+            Py_TYPE(next_iter)->tp_name);
+    }
+    Py_DECREF(next_iter);
+    return awaitable;
+}
+
+PyObject *
+_PyEval_LoadGlobal(PyObject *globals, PyObject *builtins, PyObject *name)
+{
+    PyObject *res;
+    if (PyDict_CheckExact(globals) && PyDict_CheckExact(builtins)) {
+        res = _PyDict_LoadGlobal((PyDictObject *)globals,
+                                    (PyDictObject *)builtins,
+                                    name);
+        if (res == NULL && !PyErr_Occurred()) {
+            /* _PyDict_LoadGlobal() returns NULL without raising
+                * an exception if the key doesn't exist */
+            _PyEval_FormatExcCheckArg(PyThreadState_GET(), PyExc_NameError,
+                                        NAME_ERROR_MSG, name);
+        }
+    }
+    else {
+        /* Slow-path if globals or builtins is not a dict */
+        /* namespace 1: globals */
+        if (PyMapping_GetOptionalItem(globals, name, &res) < 0) {
+            return NULL;
+        }
+        if (res == NULL) {
+            /* namespace 2: builtins */
+            if (PyMapping_GetOptionalItem(builtins, name, &res) < 0) {
+                return NULL;
+            }
+            if (res == NULL) {
+                _PyEval_FormatExcCheckArg(
+                            PyThreadState_GET(), PyExc_NameError,
+                            NAME_ERROR_MSG, name);
+            }
+        }
+    }
+    return res;
+}
+
+PyObject *
+_PyEval_GetAwaitable(PyObject *iterable, int oparg)
+{
+    PyObject *iter = _PyCoro_GetAwaitableIter(iterable);
+
+    if (iter == NULL) {
+        _PyEval_FormatAwaitableError(PyThreadState_GET(),
+            Py_TYPE(iterable), oparg);
+    }
+    else if (PyCoro_CheckExact(iter)) {
+        PyObject *yf = _PyGen_yf((PyGenObject*)iter);
+        if (yf != NULL) {
+            /* `iter` is a coroutine object that is being
+                awaited, `yf` is a pointer to the current awaitable
+                being awaited on. */
+            Py_DECREF(yf);
+            Py_CLEAR(iter);
+            _PyErr_SetString(PyThreadState_GET(), PyExc_RuntimeError,
+                                "coroutine is being awaited already");
+        }
+    }
+    return iter;
+}
+
+PyObject *
+_PyEval_LoadName(PyThreadState *tstate, _PyInterpreterFrame *frame, PyObject *name)
+{
+
+    PyObject *value;
+    if (frame->f_locals == NULL) {
+        _PyErr_SetString(tstate, PyExc_SystemError,
+                            "no locals found");
+        return NULL;
+    }
+    if (PyMapping_GetOptionalItem(frame->f_locals, name, &value) < 0) {
+        return NULL;
+    }
+    if (value != NULL) {
+        return value;
+    }
+    if (PyDict_GetItemRef(frame->f_globals, name, &value) < 0) {
+        return NULL;
+    }
+    if (value != NULL) {
+        return value;
+    }
+    if (PyMapping_GetOptionalItem(frame->f_builtins, name, &value) < 0) {
+        return NULL;
+    }
+    if (value == NULL) {
+        _PyEval_FormatExcCheckArg(
+                    tstate, PyExc_NameError,
+                    NAME_ERROR_MSG, name);
+    }
+    return value;
+}
+
+