Function ufunc_generic_fastcall

numpy/core/src/umath/ufunc_object.c:4706–5047

* Main ufunc call implementation. * * This implementation makes use of the "fastcall" way of passing keyword * arguments and is called directly from `ufunc_generic_vectorcall` when * Python has `tp_vectorcall` (Python 3.8+). * If `tp_vectorcall` is not available, the dictionary `kwargs` are unpacked in * `ufunc_generic_call` with fairly little overhead. */

 * `ufunc_generic_call` with fairly little overhead.
 */
static PyObject *
ufunc_generic_fastcall(PyUFuncObject *ufunc,
        PyObject *const *args, Py_ssize_t len_args, PyObject *kwnames,
        npy_bool outer)
{
    int errval;
    int nin = ufunc->nin, nout = ufunc->nout, nop = ufunc->nargs;

    /* All following variables are cleared in the `fail` error path */
    ufunc_full_args full_args;
    PyArrayObject *wheremask = NULL;

    PyArray_DTypeMeta *signature[NPY_MAXARGS];
    PyArrayObject *operands[NPY_MAXARGS];
    PyArray_DTypeMeta *operand_DTypes[NPY_MAXARGS];
    PyArray_Descr *operation_descrs[NPY_MAXARGS];
    PyObject *output_array_prepare[NPY_MAXARGS];
    /* Initialize all arrays (we usually only need a small part) */
    memset(signature, 0, nop * sizeof(*signature));
    memset(operands, 0, nop * sizeof(*operands));
    memset(operand_DTypes, 0, nop * sizeof(*operation_descrs));
    memset(operation_descrs, 0, nop * sizeof(*operation_descrs));
    memset(output_array_prepare, 0, nout * sizeof(*output_array_prepare));

    /*
     * Note that the input (and possibly output) arguments are passed in as
     * positional arguments. We extract these first and check for `out`
     * passed by keyword later.
     * Outputs and inputs are stored in `full_args.in` and `full_args.out`
     * as tuples (or NULL when no outputs are passed).
     */

    /* Check number of arguments */
    if (NPY_UNLIKELY((len_args < nin) || (len_args > nop))) {
        PyErr_Format(PyExc_TypeError,
                "%s() takes from %d to %d positional arguments but "
                "%zd were given",
                ufunc_get_name_cstr(ufunc) , nin, nop, len_args);
        return NULL;
    }

    /* Fetch input arguments. */
    full_args.in = PyArray_TupleFromItems(ufunc->nin, args, 0);
    if (full_args.in == NULL) {
        return NULL;
    }

    /*
     * If there are more arguments, they define the out args. Otherwise
     * full_args.out is NULL for now, and the `out` kwarg may still be passed.
     */
    npy_bool out_is_passed_by_position = len_args > nin;
    if (out_is_passed_by_position) {
        npy_bool all_none = NPY_TRUE;

        full_args.out = PyTuple_New(nout);
        if (full_args.out == NULL) {
            goto fail;