[FLOPS] add flops compute module

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

@@ -24,6 +24,8 @@
 import paddle.fluid.core as core
 import paddle.fluid.proto.profiler.profiler_pb2 as profiler_pb2
 
+from paddle.utils.flops import flops
+
 
 class TestProfiler(unittest.TestCase):
     @classmethod
@@ -221,6 +223,12 @@ def test_errors(self):
             self.assertTrue(global_profiler != prof)
 
 
+class TestFLOPSAPI(unittest.TestCase):
+    def test_flops(self):
+        self.assertTrue(flops('relu', ([12, 12],), output=4) == 144)
+        self.assertTrue(flops('dropout', ([12, 12],), **{'output': 4}) == 0)
+
+
 if __name__ == '__main__':
     paddle.enable_static()
     unittest.main()

python/paddle/utils/flops.py

@@ -0,0 +1,60 @@
+# Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
+#
+# 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
+#
+#     http://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.
+
+from numpy import prod
+
+_FLOPS_COMPUTE_FUNC_MAP = {}
+
+
+def flops(op_type: str, input_shapes: tuple, **attrs) -> int:
+    """
+    count flops for operation.
+
+    Args:
+        op_type (str): the type of operation.
+        input_shapes (tuple): the shapes of inputs.
+        attrs (dict): the attributes of the operation.
+
+    Returns:
+        the total flops of the operation.
+    """
+
+    if op_type not in _FLOPS_COMPUTE_FUNC_MAP:
+        return 0
+    else:
+        func = _FLOPS_COMPUTE_FUNC_MAP[op_type]
+        return func(input_shapes, **attrs)
+
+
+def register_flops(op_type):
+    """
+    register flops computation function for operation.
+    """
+
+    def register(func):
+        global _FLOPS_COMPUTE_FUNC_MAP
+        _FLOPS_COMPUTE_FUNC_MAP[op_type] = func
+        return func
+
+    return register
+
+
+@register_flops("dropout")
+def _dropout_flops(input_shapes, **attrs):
+    return 0
+
+
+@register_flops("relu")
+def _relu_flops(input_shapes, **attrs):
+    return prod(input_shapes[0])