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MAINT: Simplify reference counting in the np.array() internal code
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@seberg @ngoldbaum
seberg authored and ngoldbaum committed Mar 20, 2023
1 parent 4ecdd83 commit c45a101
Showing 1 changed file with 35 additions and 54 deletions.
89 changes: 35 additions & 54 deletions numpy/core/src/multiarray/multiarraymodule.c
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Expand Up @@ -1635,77 +1635,63 @@ _prepend_ones(PyArrayObject *arr, int nd, int ndmin, NPY_ORDER order)
((order) == NPY_CORDER && PyArray_IS_C_CONTIGUOUS(op)) || \
((order) == NPY_FORTRANORDER && PyArray_IS_F_CONTIGUOUS(op)))

/*
* NOTE: in_descr is passed as a reference to a pointer because there is a
* code path where the pointer can be changed via Py_XSETREF and we need to
* make sure the mutated pointer is available for the caller.
*/

static inline PyObject *
_array_fromobject_generic(
PyObject *op, PyArray_Descr **in_descr, PyArray_DTypeMeta *in_DType,
PyObject *op, PyArray_Descr *in_descr, PyArray_DTypeMeta *in_DType,
_PyArray_CopyMode copy, NPY_ORDER order, npy_bool subok, int ndmin)
{
PyArrayObject *oparr = NULL, *ret = NULL;
PyArray_Descr *oldtype = NULL;
int nd, flags = 0;

/* Hold on to `in_descr` as `dtype`, since we may also set it below. */
Py_XINCREF(in_descr);
PyArray_Descr *dtype = in_descr;

if (ndmin > NPY_MAXDIMS) {
PyErr_Format(PyExc_ValueError,
"ndmin bigger than allowable number of dimensions "
"NPY_MAXDIMS (=%d)", NPY_MAXDIMS);
return NULL;
goto finish;
}
/* fast exit if simple call */
if (PyArray_CheckExact(op) || (subok && PyArray_Check(op))) {
oparr = (PyArrayObject *)op;
PyArray_Descr* dtype = NULL;
/*
* Skip AdaptDescriptorToArray if the supplied dtype class does not
* match the dtype of the input array or if we have to determine the
* descriptor because only the DType was given. This means we avoid
* inspecting array values twice if someone does, e.g.:
*
* >>> arr = np.array(["asdf", "fdsa"], dtype=object)
* >>> np.array(arr, dtype="U")
*/
if ((NPY_DTYPE(PyArray_DESCR(oparr)) == in_DType) ||
((*in_descr == NULL) && (in_DType != NULL))) {
dtype = PyArray_AdaptDescriptorToArray(
oparr, in_DType, *in_descr);
if (dtype == NULL) {
return NULL;
}
Py_INCREF(dtype);
Py_XSETREF(*in_descr, dtype);
}
else {
if ((*in_descr == NULL) && (in_DType == NULL)) {
dtype = PyArray_DESCR(oparr);
}
else {
dtype = *in_descr;
}
Py_INCREF(dtype);
}
if ((*in_descr == NULL) && (in_DType == NULL)) {

if (dtype == NULL && in_DType == NULL) {
/*
* User did not ask for a specific dtype instance or class. So
* we can return either self or a copy.
*/
if (copy != NPY_COPY_ALWAYS && STRIDING_OK(oparr, order)) {
ret = oparr;
Py_INCREF(ret);
Py_DECREF(dtype);
goto finish;
}
else {
if (copy == NPY_COPY_NEVER) {
PyErr_SetString(PyExc_ValueError,
"Unable to avoid copy while creating a new array.");
return NULL;
goto finish;
}
ret = (PyArrayObject *)PyArray_NewCopy(oparr, order);
Py_DECREF(dtype);
goto finish;
}
}
else if (dtype == NULL) {
/*
* If the user passed a DType class but not a dtype instance,
* we must use `PyArray_AdaptDescriptorToArray` to find the
* correct dtype instance.
* Even if the fast-path doesn't work we will use this.
*/
dtype = PyArray_AdaptDescriptorToArray(oparr, in_DType, NULL);
if (dtype == NULL) {
goto finish;
}
}

/* One more chance for faster exit if user specified the dtype. */
oldtype = PyArray_DESCR(oparr);
if (PyArray_EquivTypes(oldtype, dtype)) {
Expand All @@ -1731,31 +1717,24 @@ _array_fromobject_generic(
op
);
}
Py_DECREF(dtype);
goto finish;
}
else {
if (copy == NPY_COPY_NEVER) {
PyErr_SetString(PyExc_ValueError,
"Unable to avoid copy while creating a new array.");
Py_DECREF(dtype);
return NULL;
goto finish;
}
ret = (PyArrayObject *)PyArray_NewCopy(oparr, order);
if (oldtype == dtype || ret == NULL) {
Py_DECREF(dtype);
goto finish;
}
Py_INCREF(oldtype);
Py_DECREF(PyArray_DESCR(ret));
Py_DECREF(dtype);
((PyArrayObject_fields *)ret)->descr = oldtype;
goto finish;
}
}
else {
Py_DECREF(dtype);
}
}

if (copy == NPY_COPY_ALWAYS) {
Expand All @@ -1780,9 +1759,11 @@ _array_fromobject_generic(
flags |= NPY_ARRAY_FORCECAST;

ret = (PyArrayObject *)PyArray_CheckFromAny_int(
op, *in_descr, in_DType, 0, 0, flags, NULL);
op, dtype, in_DType, 0, 0, flags, NULL);

finish:
Py_XDECREF(dtype);

if (ret == NULL) {
return NULL;
}
Expand Down Expand Up @@ -1844,7 +1825,7 @@ array_array(PyObject *NPY_UNUSED(ignored),
}

PyObject *res = _array_fromobject_generic(
op, &dt_info.descr, dt_info.dtype, copy, order, subok, ndmin);
op, dt_info.descr, dt_info.dtype, copy, order, subok, ndmin);
Py_XDECREF(dt_info.descr);
Py_XDECREF(dt_info.dtype);
return res;
Expand Down Expand Up @@ -1886,7 +1867,7 @@ array_asarray(PyObject *NPY_UNUSED(ignored),
}

PyObject *res = _array_fromobject_generic(
op, &dt_info.descr, dt_info.dtype, NPY_FALSE, order, NPY_FALSE, 0);
op, dt_info.descr, dt_info.dtype, NPY_FALSE, order, NPY_FALSE, 0);
Py_XDECREF(dt_info.descr);
Py_XDECREF(dt_info.dtype);
return res;
Expand Down Expand Up @@ -1928,7 +1909,7 @@ array_asanyarray(PyObject *NPY_UNUSED(ignored),
}

PyObject *res = _array_fromobject_generic(
op, &dt_info.descr, dt_info.dtype, NPY_FALSE, order, NPY_TRUE, 0);
op, dt_info.descr, dt_info.dtype, NPY_FALSE, order, NPY_TRUE, 0);
Py_XDECREF(dt_info.descr);
Py_XDECREF(dt_info.dtype);
return res;
Expand Down Expand Up @@ -1969,7 +1950,7 @@ array_ascontiguousarray(PyObject *NPY_UNUSED(ignored),
}

PyObject *res = _array_fromobject_generic(
op, &dt_info.descr, dt_info.dtype, NPY_FALSE, NPY_CORDER, NPY_FALSE,
op, dt_info.descr, dt_info.dtype, NPY_FALSE, NPY_CORDER, NPY_FALSE,
1);
Py_XDECREF(dt_info.descr);
Py_XDECREF(dt_info.dtype);
Expand Down Expand Up @@ -2011,7 +1992,7 @@ array_asfortranarray(PyObject *NPY_UNUSED(ignored),
}

PyObject *res = _array_fromobject_generic(
op, &dt_info.descr, dt_info.dtype, NPY_FALSE, NPY_FORTRANORDER,
op, dt_info.descr, dt_info.dtype, NPY_FALSE, NPY_FORTRANORDER,
NPY_FALSE, 1);
Py_XDECREF(dt_info.descr);
Py_XDECREF(dt_info.dtype);
Expand Down

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