[CI] Solve occasional CI issue when pad value is all 0 (#3801)

python/tvm/relay/frontend/coreml.py

@@ -74,6 +74,7 @@ def _ConvolutionLayerParams(op, inexpr, etab):
             pad_l = valid.paddingAmounts.borderAmounts[1].startEdgeSize
             pad_b = valid.paddingAmounts.borderAmounts[0].endEdgeSize
             pad_r = valid.paddingAmounts.borderAmounts[1].endEdgeSize
+            if not all(v == 0 for v in (pad_t, pad_l, pad_b, pad_r)):
                 inexpr = _op.nn.pad(data=inexpr, pad_width=((0, 0),
                                                             (0, 0),
                                                             (pad_t, pad_b),
@@ -208,6 +209,7 @@ def _PoolingLayerParams(op, inexpr, etab):
                 pad_l = valid.paddingAmounts.borderAmounts[1].startEdgeSize
                 pad_b = valid.paddingAmounts.borderAmounts[0].endEdgeSize
                 pad_r = valid.paddingAmounts.borderAmounts[1].endEdgeSize
+                if not all(v == 0 for v in (pad_t, pad_l, pad_b, pad_r)):
                     params['padding'] = [pad_t, pad_l, pad_b, pad_r]
         elif op.WhichOneof('PoolingPaddingType') == 'includeLastPixel':
             # I don't know if this is correct

tests/python/frontend/coreml/model_zoo/__init__.py

@@ -20,5 +20,7 @@ def get_cat_image():
     dst = 'cat.png'
     real_dst = download_testdata(url, dst, module='data')
     img = Image.open(real_dst).resize((224, 224))
-    img = np.transpose(img, (2, 0, 1))[np.newaxis, :]
+    # CoreML's standard model image format is BGR
+    img_bgr = np.array(img)[:, :, ::-1]
+    img = np.transpose(img_bgr, (2, 0, 1))[np.newaxis, :]
     return np.asarray(img)
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