fix elementwise_add_ and elementwise_sub_ broadcast problem

Author: pangyoki

python/paddle/fluid/tests/unittests/test_elementwise_add_op.py

@@ -449,6 +449,32 @@ def _executed_api(self):
         self.add = paddle.add_
 
 
+class TestAddInplaceBroadcast(unittest.TestCase):
+    def test_broadcast_success(self):
+        paddle.disable_static()
+        x_numpy = np.random.rand(2, 3, 4).astype('float')
+        y_numpy = np.random.rand(3, 4).astype('float')
+
+        x = paddle.to_tensor(x_numpy)
+        y = paddle.to_tensor(y_numpy)
+
+        inplace_result = paddle.add_(x, y)
+        numpy_result = x_numpy + y_numpy
+        self.assertEqual((inplace_result.numpy() == numpy_result).all(), True)
+        paddle.enable_static()
+
+    def test_broadcast_errors(self):
+        paddle.disable_static()
+        x = paddle.rand([3, 4])
+        y = paddle.rand([2, 3, 4])
+
+        def broadcast_shape_error():
+            paddle.add_(x, y)
+
+        self.assertRaises(ValueError, broadcast_shape_error)
+        paddle.enable_static()
+
+
 class TestComplexElementwiseAddOp(OpTest):
     def setUp(self):
         self.op_type = "elementwise_add"

python/paddle/fluid/tests/unittests/test_elementwise_sub_op.py

@@ -289,6 +289,32 @@ def _executed_api(self):
         self.subtract = paddle.subtract_
 
 
+class TestSubtractInplaceBroadcast(unittest.TestCase):
+    def test_broadcast_success(self):
+        paddle.disable_static()
+        x_numpy = np.random.rand(2, 3, 4).astype('float')
+        y_numpy = np.random.rand(3, 4).astype('float')
+
+        x = paddle.to_tensor(x_numpy)
+        y = paddle.to_tensor(y_numpy)
+
+        inplace_result = paddle.subtract_(x, y)
+        numpy_result = x_numpy - y_numpy
+        self.assertEqual((inplace_result.numpy() == numpy_result).all(), True)
+        paddle.enable_static()
+
+    def test_broadcast_errors(self):
+        paddle.disable_static()
+        x = paddle.rand([3, 4])
+        y = paddle.rand([2, 3, 4])
+
+        def broadcast_shape_error():
+            paddle.subtract_(x, y)
+
+        self.assertRaises(ValueError, broadcast_shape_error)
+        paddle.enable_static()
+
+
 if __name__ == '__main__':
     paddle.enable_static()
     unittest.main()

python/paddle/tensor/math.py

@@ -321,8 +321,12 @@ def add_(x, y, name=None):
     if in_dygraph_mode():
         op_type = 'elementwise_add_'
         axis = -1
-        return _elementwise_op_in_dygraph(
+        inplace_shape = x.shape
+        out = _elementwise_op_in_dygraph(
             x, y, axis=axis, op_name=op_type)
+        if inplace_shape != out.shape:
+            raise ValueError("The shape of broadcast output {} is different from that of inplace tensor {} in the Inplace operation.".format(out.shape, inplace_shape))
+        return out
     _print_warning_in_static_mode("elementwise_add")
     return _elementwise_op(LayerHelper('elementwise_add', **locals()))
 
@@ -396,8 +400,12 @@ def subtract_(x, y, name=None):
     if in_dygraph_mode():
         axis = -1
         act = None
-        return _elementwise_op_in_dygraph(
+        inplace_shape = x.shape
+        out = _elementwise_op_in_dygraph(
             x, y, axis=axis, act=act, op_name='elementwise_sub_')
+        if inplace_shape != out.shape:
+            raise ValueError("The shape of broadcast output {} is different from that of inplace tensor {} in the Inplace operation.".format(out.shape, inplace_shape))
+        return out
     _print_warning_in_static_mode("elementwise_sub")
     return _elementwise_op(LayerHelper('elementwise_sub', **locals()))
 

tools/wlist.json

@@ -78,10 +78,6 @@
             "name":"clip_",
             "annotation":"Inplace APIs don't need sample code. There is a special document introducing Inplace strategy"
         },
-        {
-            "name":"log_",
-            "annotation":"Inplace APIs don't need sample code. There is a special document introducing Inplace strategy"
-        },
         {
             "name":"scale_",
             "annotation":"Inplace APIs don't need sample code. There is a special document introducing Inplace strategy"