Add test for export of QuantReLu

tests/brevitas/test_brevitas_relu_act_export.py

+import onnx  # noqa
+import numpy as np
+import torch
+import brevitas.onnx as bo
+from brevitas.nn import QuantReLU
+from brevitas.core.quant import QuantType
+from brevitas.core.restrict_val import RestrictValueType
+from brevitas.core.scaling import ScalingImplType
+import pytest
+from finn.core.modelwrapper import ModelWrapper
+import finn.core.onnx_exec as oxe
+from finn.transformation.infer_shapes import InferShapes
+
+export_onnx_path = "test_act.onnx"
+
+
+@pytest.mark.parametrize("abits", [1, 2, 4, 8])
+@pytest.mark.parametrize("max_val", [1.0, 1.5, 1 - 2 ** (-7)])
+@pytest.mark.parametrize(
+    "scaling_impl_type", [ScalingImplType.CONST, ScalingImplType.PARAMETER]
+)
+def test_brevitas_relu_act_export(abits, max_val, scaling_impl_type):
+    min_val = -1.0
+    ishape = (1, 15)
+    b_act = QuantReLU(
+        bit_width=abits,
+        max_val=max_val,
+        scaling_impl_type=scaling_impl_type,
+        restrict_scaling_type=RestrictValueType.LOG_FP,
+        quant_type=QuantType.INT,
+    )
+    if scaling_impl_type == ScalingImplType.PARAMETER:
+        checkpoint = {
+            "act_quant_proxy.fused_activation_quant_proxy.tensor_quant.\
+scaling_impl.learned_value": torch.tensor(
+                0.49
+            ).type(
+                torch.FloatTensor
+            )
+        }
+        b_act.load_state_dict(checkpoint)
+
+    bo.export_finn_onnx(b_act, ishape, export_onnx_path)
+    model = ModelWrapper(export_onnx_path)
+    model = model.transform(InferShapes())
+    inp_tensor = np.random.uniform(low=min_val, high=max_val, size=ishape).astype(
+        np.float32
+    )
+    idict = {model.graph.input[0].name: inp_tensor}
+    odict = oxe.execute_onnx(model, idict, True)
+    produced = odict[model.graph.output[0].name]
+    inp_tensor = torch.from_numpy(inp_tensor).float()
+    b_act.eval()
+    expected = b_act.forward(inp_tensor).detach().numpy()
+    if not np.isclose(produced, expected, atol=1e-3).all():
+        print(abits, max_val, scaling_impl_type)
+        print("scale: ", b_act.quant_act_scale().type(torch.FloatTensor).detach())
+        if abits < 5:
+            print(
+                "thres:",
+                ", ".join(["{:8.4f}".format(x) for x in b_act.export_thres[0]]),
+            )
+        print("input:", ", ".join(["{:8.4f}".format(x) for x in inp_tensor[0]]))
+        print("prod :", ", ".join(["{:8.4f}".format(x) for x in produced[0]]))
+        print("expec:", ", ".join(["{:8.4f}".format(x) for x in expected[0]]))
+
+    assert np.isclose(produced, expected, atol=1e-3).all()