Corrected order='K' support in astype

Array API tests pointed out an error in implementation of order='K'
in dpctl.tensor.astype. Moved _empty_like_orderK and fried from
_type_utils to _copy_utils and used it to implement astype.

Modified import statement in _elementwise_common where _empty_like*
are used.

Author: oleksandr-pavlyk

dpctl/tensor/_copy_utils.py

@@ -13,6 +13,7 @@
 #  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
+import builtins
 import operator
 
 import numpy as np
@@ -361,6 +362,96 @@ def copy(usm_ary, order="K"):
     return R
 
 
+def _empty_like_orderK(X, dt, usm_type=None, dev=None):
+    """Returns empty array like `x`, using order='K'
+
+    For an array `x` that was obtained by permutation of a contiguous
+    array the returned array will have the same shape and the same
+    strides as `x`.
+    """
+    if not isinstance(X, dpt.usm_ndarray):
+        raise TypeError(f"Expected usm_ndarray, got {type(X)}")
+    if usm_type is None:
+        usm_type = X.usm_type
+    if dev is None:
+        dev = X.device
+    fl = X.flags
+    if fl["C"] or X.size <= 1:
+        return dpt.empty_like(
+            X, dtype=dt, usm_type=usm_type, device=dev, order="C"
+        )
+    elif fl["F"]:
+        return dpt.empty_like(
+            X, dtype=dt, usm_type=usm_type, device=dev, order="F"
+        )
+    st = list(X.strides)
+    perm = sorted(
+        range(X.ndim), key=lambda d: builtins.abs(st[d]), reverse=True
+    )
+    inv_perm = sorted(range(X.ndim), key=lambda i: perm[i])
+    st_sorted = [st[i] for i in perm]
+    sh = X.shape
+    sh_sorted = tuple(sh[i] for i in perm)
+    R = dpt.empty(sh_sorted, dtype=dt, usm_type=usm_type, device=dev, order="C")
+    if min(st_sorted) < 0:
+        sl = tuple(
+            slice(None, None, -1)
+            if st_sorted[i] < 0
+            else slice(None, None, None)
+            for i in range(X.ndim)
+        )
+        R = R[sl]
+    return dpt.permute_dims(R, inv_perm)
+
+
+def _empty_like_pair_orderK(X1, X2, dt, res_shape, usm_type, dev):
+    if not isinstance(X1, dpt.usm_ndarray):
+        raise TypeError(f"Expected usm_ndarray, got {type(X1)}")
+    if not isinstance(X2, dpt.usm_ndarray):
+        raise TypeError(f"Expected usm_ndarray, got {type(X2)}")
+    nd1 = X1.ndim
+    nd2 = X2.ndim
+    if nd1 > nd2 and X1.shape == res_shape:
+        return _empty_like_orderK(X1, dt, usm_type, dev)
+    elif nd1 < nd2 and X2.shape == res_shape:
+        return _empty_like_orderK(X2, dt, usm_type, dev)
+    fl1 = X1.flags
+    fl2 = X2.flags
+    if fl1["C"] or fl2["C"]:
+        return dpt.empty(
+            res_shape, dtype=dt, usm_type=usm_type, device=dev, order="C"
+        )
+    if fl1["F"] and fl2["F"]:
+        return dpt.empty(
+            res_shape, dtype=dt, usm_type=usm_type, device=dev, order="F"
+        )
+    st1 = list(X1.strides)
+    st2 = list(X2.strides)
+    max_ndim = max(nd1, nd2)
+    st1 += [0] * (max_ndim - len(st1))
+    st2 += [0] * (max_ndim - len(st2))
+    perm = sorted(
+        range(max_ndim),
+        key=lambda d: (builtins.abs(st1[d]), builtins.abs(st2[d])),
+        reverse=True,
+    )
+    inv_perm = sorted(range(max_ndim), key=lambda i: perm[i])
+    st1_sorted = [st1[i] for i in perm]
+    st2_sorted = [st2[i] for i in perm]
+    sh = res_shape
+    sh_sorted = tuple(sh[i] for i in perm)
+    R = dpt.empty(sh_sorted, dtype=dt, usm_type=usm_type, device=dev, order="C")
+    if max(min(st1_sorted), min(st2_sorted)) < 0:
+        sl = tuple(
+            slice(None, None, -1)
+            if (st1_sorted[i] < 0 and st2_sorted[i] < 0)
+            else slice(None, None, None)
+            for i in range(nd1)
+        )
+        R = R[sl]
+    return dpt.permute_dims(R, inv_perm)
+
+
 def astype(usm_ary, newdtype, order="K", casting="unsafe", copy=True):
     """ astype(array, new_dtype, order="K", casting="unsafe", \
             copy=True)
@@ -432,26 +523,15 @@ def astype(usm_ary, newdtype, order="K", casting="unsafe", copy=True):
             "Unrecognized value of the order keyword. "
             "Recognized values are 'A', 'C', 'F', or 'K'"
         )
-    R = dpt.usm_ndarray(
-        usm_ary.shape,
-        dtype=target_dtype,
-        buffer=usm_ary.usm_type,
-        order=copy_order,
-        buffer_ctor_kwargs={"queue": usm_ary.sycl_queue},
-    )
-    if order == "K" and (not c_contig and not f_contig):
-        original_strides = usm_ary.strides
-        ind = sorted(
-            range(usm_ary.ndim),
-            key=lambda i: abs(original_strides[i]),
-            reverse=True,
-        )
-        new_strides = tuple(R.strides[ind[i]] for i in ind)
+    if order == "K":
+        R = _empty_like_orderK(usm_ary, target_dtype)
+    else:
         R = dpt.usm_ndarray(
             usm_ary.shape,
             dtype=target_dtype,
-            buffer=R.usm_data,
-            strides=new_strides,
+            buffer=usm_ary.usm_type,
+            order=copy_order,
+            buffer_ctor_kwargs={"queue": usm_ary.sycl_queue},
         )
     _copy_from_usm_ndarray_to_usm_ndarray(R, usm_ary)
     return R

dpctl/tensor/_elementwise_common.py

@@ -26,10 +26,9 @@
 from dpctl.tensor._usmarray import _is_object_with_buffer_protocol as _is_buffer
 from dpctl.utils import ExecutionPlacementError
 
+from ._copy_utils import _empty_like_orderK, _empty_like_pair_orderK
 from ._type_utils import (
     _acceptance_fn_default,
-    _empty_like_orderK,
-    _empty_like_pair_orderK,
     _find_buf_dtype,
     _find_buf_dtype2,
     _find_inplace_dtype,

dpctl/tensor/_type_utils.py

@@ -14,8 +14,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-import builtins
-
 import dpctl.tensor as dpt
 import dpctl.tensor._tensor_impl as ti
 
@@ -116,96 +114,6 @@ def _can_cast(from_: dpt.dtype, to_: dpt.dtype, _fp16: bool, _fp64: bool):
     return can_cast_v
 
 
-def _empty_like_orderK(X, dt, usm_type=None, dev=None):
-    """Returns empty array like `x`, using order='K'
-
-    For an array `x` that was obtained by permutation of a contiguous
-    array the returned array will have the same shape and the same
-    strides as `x`.
-    """
-    if not isinstance(X, dpt.usm_ndarray):
-        raise TypeError(f"Expected usm_ndarray, got {type(X)}")
-    if usm_type is None:
-        usm_type = X.usm_type
-    if dev is None:
-        dev = X.device
-    fl = X.flags
-    if fl["C"] or X.size <= 1:
-        return dpt.empty_like(
-            X, dtype=dt, usm_type=usm_type, device=dev, order="C"
-        )
-    elif fl["F"]:
-        return dpt.empty_like(
-            X, dtype=dt, usm_type=usm_type, device=dev, order="F"
-        )
-    st = list(X.strides)
-    perm = sorted(
-        range(X.ndim), key=lambda d: builtins.abs(st[d]), reverse=True
-    )
-    inv_perm = sorted(range(X.ndim), key=lambda i: perm[i])
-    st_sorted = [st[i] for i in perm]
-    sh = X.shape
-    sh_sorted = tuple(sh[i] for i in perm)
-    R = dpt.empty(sh_sorted, dtype=dt, usm_type=usm_type, device=dev, order="C")
-    if min(st_sorted) < 0:
-        sl = tuple(
-            slice(None, None, -1)
-            if st_sorted[i] < 0
-            else slice(None, None, None)
-            for i in range(X.ndim)
-        )
-        R = R[sl]
-    return dpt.permute_dims(R, inv_perm)
-
-
-def _empty_like_pair_orderK(X1, X2, dt, res_shape, usm_type, dev):
-    if not isinstance(X1, dpt.usm_ndarray):
-        raise TypeError(f"Expected usm_ndarray, got {type(X1)}")
-    if not isinstance(X2, dpt.usm_ndarray):
-        raise TypeError(f"Expected usm_ndarray, got {type(X2)}")
-    nd1 = X1.ndim
-    nd2 = X2.ndim
-    if nd1 > nd2 and X1.shape == res_shape:
-        return _empty_like_orderK(X1, dt, usm_type, dev)
-    elif nd1 < nd2 and X2.shape == res_shape:
-        return _empty_like_orderK(X2, dt, usm_type, dev)
-    fl1 = X1.flags
-    fl2 = X2.flags
-    if fl1["C"] or fl2["C"]:
-        return dpt.empty(
-            res_shape, dtype=dt, usm_type=usm_type, device=dev, order="C"
-        )
-    if fl1["F"] and fl2["F"]:
-        return dpt.empty(
-            res_shape, dtype=dt, usm_type=usm_type, device=dev, order="F"
-        )
-    st1 = list(X1.strides)
-    st2 = list(X2.strides)
-    max_ndim = max(nd1, nd2)
-    st1 += [0] * (max_ndim - len(st1))
-    st2 += [0] * (max_ndim - len(st2))
-    perm = sorted(
-        range(max_ndim),
-        key=lambda d: (builtins.abs(st1[d]), builtins.abs(st2[d])),
-        reverse=True,
-    )
-    inv_perm = sorted(range(max_ndim), key=lambda i: perm[i])
-    st1_sorted = [st1[i] for i in perm]
-    st2_sorted = [st2[i] for i in perm]
-    sh = res_shape
-    sh_sorted = tuple(sh[i] for i in perm)
-    R = dpt.empty(sh_sorted, dtype=dt, usm_type=usm_type, device=dev, order="C")
-    if max(min(st1_sorted), min(st2_sorted)) < 0:
-        sl = tuple(
-            slice(None, None, -1)
-            if (st1_sorted[i] < 0 and st2_sorted[i] < 0)
-            else slice(None, None, None)
-            for i in range(nd1)
-        )
-        R = R[sl]
-    return dpt.permute_dims(R, inv_perm)
-
-
 def _to_device_supported_dtype(dt, dev):
     has_fp16 = dev.has_aspect_fp16
     has_fp64 = dev.has_aspect_fp64
@@ -339,8 +247,6 @@ def _find_inplace_dtype(lhs_dtype, rhs_dtype, query_fn, sycl_dev):
     "_find_buf_dtype",
     "_find_buf_dtype2",
     "_find_inplace_dtype",
-    "_empty_like_orderK",
-    "_empty_like_pair_orderK",
     "_to_device_supported_dtype",
     "_acceptance_fn_default",
     "_acceptance_fn_divide",

dpctl/tests/elementwise/test_type_utils.py

@@ -18,6 +18,7 @@
 
 import dpctl
 import dpctl.tensor as dpt
+import dpctl.tensor._copy_utils as cu
 import dpctl.tensor._type_utils as tu
 
 from .utils import _all_dtypes, _map_to_device_dtype
@@ -73,15 +74,15 @@ def test_type_utils_empty_like_orderK():
         a = dpt.empty((10, 10), dtype=dpt.int32, order="F")
     except dpctl.SyclDeviceCreationError:
         pytest.skip("No SYCL devices available")
-    X = tu._empty_like_orderK(a, dpt.int32, a.usm_type, a.device)
+    X = cu._empty_like_orderK(a, dpt.int32, a.usm_type, a.device)
     assert X.flags["F"]
 
 
 def test_type_utils_empty_like_orderK_invalid_args():
     with pytest.raises(TypeError):
-        tu._empty_like_orderK([1, 2, 3], dpt.int32, "device", None)
+        cu._empty_like_orderK([1, 2, 3], dpt.int32, "device", None)
     with pytest.raises(TypeError):
-        tu._empty_like_pair_orderK(
+        cu._empty_like_pair_orderK(
             [1, 2, 3],
             (
                 1,
@@ -98,7 +99,7 @@ def test_type_utils_empty_like_orderK_invalid_args():
     except dpctl.SyclDeviceCreationError:
         pytest.skip("No SYCL devices available")
     with pytest.raises(TypeError):
-        tu._empty_like_pair_orderK(
+        cu._empty_like_pair_orderK(
             a,
             (
                 1,