Function TFE_Py_FastPathExecute_C

tensorflow/python/eager/pywrap_tfe_src.cc:2898–3231

}  // namespace

PyObject* TFE_Py_FastPathExecute_C(PyObject*, PyObject* args) {
  Py_ssize_t args_size = PyTuple_GET_SIZE(args);
  if (args_size < kFastPathExecuteInputStartIndex) {
    PyErr_SetString(
        PyExc_ValueError,
        Printf("There must be at least %d items in the input tuple.",
               kFastPathExecuteInputStartIndex)
            .c_str());
    return nullptr;
  }

  FastPathOpExecInfo op_exec_info;

  op_exec_info.ctx = reinterpret_cast<TFE_Context*>(
      PyCapsule_GetPointer(PyTuple_GET_ITEM(args, 0), nullptr));
  op_exec_info.args = args;

  if (op_exec_info.ctx == nullptr) {
    // The context hasn't been initialized. It will be in the slow path.
    RaiseFallbackException(
        "This function does not handle the case of the path where "
        "all inputs are not already EagerTensors.");
    return nullptr;
  }

  op_exec_info.device_name = GetDeviceName(PyTuple_GET_ITEM(args, 1));
  op_exec_info.op_name = PyTuple_GET_ITEM(args, 2);
  op_exec_info.op_def = GetOpDef(op_exec_info.op_name);
  if (op_exec_info.op_def == nullptr) return nullptr;
  op_exec_info.name = PyTuple_GET_ITEM(args, 3);
  op_exec_info.callbacks = PyTuple_GET_ITEM(args, 4);

  const tensorflow::OpDef* op_def = op_exec_info.op_def;

  // TODO(nareshmodi): Add a benchmark for the fast-path with gradient callbacks
  // (similar to benchmark_tf_gradient_function_*). Also consider using an
  // InlinedVector for flattened_attrs and flattened_inputs if the benchmarks
  // point out problems with heap allocs.
  op_exec_info.run_gradient_callback = !*ThreadTapeIsStopped() && HasTape();
  op_exec_info.run_post_exec_callbacks =
      op_exec_info.callbacks != Py_None &&
      PyList_Size(op_exec_info.callbacks) > 0;
  op_exec_info.run_callbacks = op_exec_info.run_gradient_callback ||
                               op_exec_info.run_post_exec_callbacks;

  if (args_size < kFastPathExecuteInputStartIndex + op_def->input_arg_size()) {
    PyErr_SetString(
        PyExc_ValueError,
        Printf("Tuple size smaller than intended. Expected to be at least %d, "
               "was %ld",
               kFastPathExecuteInputStartIndex + op_def->input_arg_size(),
               args_size)
            .c_str());
    return nullptr;
  }

  if (!CheckInputsOk(args, kFastPathExecuteInputStartIndex, *op_def)) {
    RaiseFallbackException(