[EXTAPI] refactor weight compression to be used by an external consumer

*lint
*added unit tests
*added typecheck
*added docstring for the api
Change-Id: Ibd4bc40d4381ac40ad2ea3d500b26c4ec565ab07
Signed-off-by: Manupa Karunaratne <manupa.karunaratne@arm.com>

1 files changed, 73 insertions, 0 deletions

diff --git a/ethosu/vela/test/extapi/test_extapi_encode_weights.py b/ethosu/vela/test/extapi/test_extapi_encode_weights.py
new file mode 100644
index 00000000..47ca02b8
--- /dev/null
+++ b/ethosu/vela/test/extapi/test_extapi_encode_weights.py
@@ -0,0 +1,73 @@
+# Copyright (C) 2020 Arm Limited or its affiliates. All rights reserved.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the License); you may
+# not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an AS IS BASIS, 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.
+# Description:
+# Contains unit tests for encode_weights API for an external consumer
+import numpy as np
+import pytest
+
+from ethosu.vela import weight_compressor
+from ethosu.vela.architecture_features import Accelerator
+
+
+@pytest.mark.parametrize(
+    "arch",
+    [
+        Accelerator.Ethos_U55_32,
+        Accelerator.Ethos_U55_64,
+        Accelerator.Ethos_U55_128,
+        Accelerator.Ethos_U55_256,
+        Accelerator.Yoda_256,
+        Accelerator.Yoda_512,
+    ],
+)
+@pytest.mark.parametrize("dilation_x", [1, 2])
+@pytest.mark.parametrize("dilation_y", [1, 2])
+@pytest.mark.parametrize("ifm_bitdepth", [8, 16])
+@pytest.mark.parametrize("depth_control", [1, 2, 3])
+@pytest.mark.parametrize("weights_shape_and_block_depth", [((16, 16, 16, 16), 8), ((3, 3, 25, 16), 8)])
+def test_encode_weights(
+    arch, weights_shape_and_block_depth, dilation_x, dilation_y, ifm_bitdepth, depth_control,
+):
+    """
+    This unit test checks the interface of the API function but not the functionality.
+    Functional correctness is tested at a system level.
+    """
+
+    weights_shape = weights_shape_and_block_depth[0]
+    ofm_block_depth = weights_shape_and_block_depth[1]
+    val_max = np.iinfo(np.uint8).max
+    weights_hwio = np.random.randint(val_max, size=weights_shape, dtype=np.uint8)
+    weights_ohwi = np.transpose(weights_hwio, (3, 0, 1, 2))
+    is_depthwise = True if depth_control == 2 else False
+    is_partkernel = True if depth_control == 3 else False
+    dilation_xy = (dilation_x, dilation_y)
+
+    encoded_stream = weight_compressor.encode_weights(
+        accelerator=arch,
+        weights_volume=weights_ohwi,
+        dilation_xy=dilation_xy,
+        ifm_bitdepth=ifm_bitdepth,
+        ofm_block_depth=ofm_block_depth,
+        is_depthwise=is_depthwise,
+        is_partkernel=is_partkernel,
+    )
+    assert type(encoded_stream) == bytearray
+
+
+if __name__ == "__main__":
+    # two test candidates for debugging purposes
+    test_encode_weights(Accelerator.Ethos_U55_256, ((3, 3, 25, 16), 8), 1, 1, 8, 0)
+    test_encode_weights(Accelerator.Ethos_U55_256, ((16, 16, 16, 16), 8), 1, 1, 8, 0)