/*
* check if in "alhs @op@ orhs" that alhs is a temporary (refcnt == 1) so we
* can do in-place operations instead of creating a new temporary
* "cannot" is set to true if it cannot be done even with swapped arguments
*/
static int
can_elide_temp(PyArrayObject * alhs, PyObject * orhs, int * cannot)
{
/*
* to be a candidate the array needs to have reference count 1, be an exact
* array of a basic type, own its data and size larger than threshold
*/
if (Py_REFCNT(alhs) != 1 || !PyArray_CheckExact(alhs) ||
!PyArray_ISNUMBER(alhs) ||
!PyArray_CHKFLAGS(alhs, NPY_ARRAY_OWNDATA) ||
!PyArray_ISWRITEABLE(alhs) ||
PyArray_CHKFLAGS(alhs, NPY_ARRAY_UPDATEIFCOPY) ||
PyArray_CHKFLAGS(alhs, NPY_ARRAY_WRITEBACKIFCOPY) ||
PyArray_NBYTES(alhs) < NPY_MIN_ELIDE_BYTES) {
return 0;
}
if (PyArray_CheckExact(orhs) ||
PyArray_CheckAnyScalar(orhs)) {
PyArrayObject * arhs;
/* create array from right hand side */
Py_INCREF(orhs);
arhs = (PyArrayObject *)PyArray_EnsureArray(orhs);
if (arhs == NULL) {
return 0;
}
/*
* if rhs is not a scalar dimensions must match
* TODO: one could allow broadcasting on equal types
*/
if (!(PyArray_NDIM(arhs) == 0 ||
(PyArray_NDIM(arhs) == PyArray_NDIM(alhs) &&
PyArray_CompareLists(PyArray_DIMS(alhs), PyArray_DIMS(arhs),
PyArray_NDIM(arhs))))) {
Py_DECREF(arhs);
return 0;
}
/* must be safe to cast (checks values for scalar in rhs) */
if (PyArray_CanCastArrayTo(arhs, PyArray_DESCR(alhs),
NPY_SAFE_CASTING)) {
Py_DECREF(arhs);
return check_callers(cannot);
}
Py_DECREF(arhs);
}
return 0;
}
/* try elide unary temporary */
NPY_NO_EXPORT int
can_elide_temp_unary(PyArrayObject * m1)
{
int cannot;
if (Py_REFCNT(m1) != 1 || !PyArray_CheckExact(m1) ||
PyArray_DESCR(m1)->type_num == NPY_VOID ||
!(PyArray_FLAGS(m1) & NPY_ARRAY_OWNDATA) ||
PyArray_NBYTES(m1) < NPY_MIN_ELIDE_BYTES) {
return 0;
}
if (check_callers(&cannot)) {
#if NPY_ELIDE_DEBUG != 0
puts("elided temporary in unary op");
#endif
return 1;
}
else {
return 0;
}
}
/* try elide unary temporary */
NPY_NO_EXPORT int
can_elide_temp_unary(PyArrayObject * m1)
{
int cannot;
if (Py_REFCNT(m1) != 1 || !PyArray_CheckExact(m1) ||
!PyArray_ISNUMBER(m1) ||
!PyArray_CHKFLAGS(m1, NPY_ARRAY_OWNDATA) ||
!PyArray_ISWRITEABLE(m1) ||
PyArray_CHKFLAGS(m1, NPY_ARRAY_UPDATEIFCOPY) ||
PyArray_NBYTES(m1) < NPY_MIN_ELIDE_BYTES) {
return 0;
}
if (check_callers(&cannot)) {
#if NPY_ELIDE_DEBUG != 0
puts("elided temporary in unary op");
#endif
return 1;
}
else {
return 0;
}
}
