Add constant folding for v1 reduce ops. (#3791)

* Add constant folding for v1 reduce ops.

* Add reference/mean.hpp.

* Remove extra semicolon.

* Address PR feedback.

src/ngraph/ngraph.hpp

@@ -181,6 +181,7 @@ namespace ngraph
 #include "ngraph/op/quantized_convolution.hpp"
 #include "ngraph/op/quantized_dot.hpp"
 #include "ngraph/op/recv.hpp"
+#include "ngraph/op/reduce_mean.hpp"
 #include "ngraph/op/reduce_prod.hpp"
 #include "ngraph/op/reduce_sum.hpp"
 #include "ngraph/op/relu.hpp"

src/ngraph/pass/constant_folding_arithmetic_reduction.cpp

@@ -19,8 +19,12 @@
 #include "ngraph/op/max.hpp"
 #include "ngraph/op/min.hpp"
 #include "ngraph/op/product.hpp"
+#include "ngraph/op/reduce_mean.hpp"
+#include "ngraph/op/reduce_prod.hpp"
+#include "ngraph/op/reduce_sum.hpp"
 #include "ngraph/op/sum.hpp"
 #include "ngraph/runtime/reference/max.hpp"
+#include "ngraph/runtime/reference/mean.hpp"
 #include "ngraph/runtime/reference/min.hpp"
 #include "ngraph/runtime/reference/product.hpp"
 #include "ngraph/runtime/reference/sum.hpp"
@@ -43,6 +47,24 @@ static shared_ptr<op::Constant>
                                    reduction_node->get_shape(),
                                    max->get_reduction_axes());
     }
+    else if (auto reduce_max = as_type_ptr<op::v1::ReduceMax>(reduction_node))
+    {
+        auto reduction_axes = reduce_max->get_reduction_axes();
+        auto input_shape = reduce_max->get_input_shape(0);
+        Shape shape_no_keep_dims;
+        for (size_t i = 0; i < input_shape.size(); i++)
+        {
+            if (reduction_axes.count(i) == 0)
+            {
+                shape_no_keep_dims.push_back(input_shape[i]);
+            }
+        }
+        runtime::reference::max<T>(constant->get_vector<T>().data(),
+                                   out_vec.data(),
+                                   constant->get_output_shape(0),
+                                   shape_no_keep_dims,
+                                   reduce_max->get_reduction_axes());
+    }
     else if (auto min = as_type_ptr<op::Min>(reduction_node))
     {
         runtime::reference::min<T>(constant->get_vector<T>().data(),
@@ -51,6 +73,24 @@ static shared_ptr<op::Constant>
                                    reduction_node->get_shape(),
                                    min->get_reduction_axes());
     }
+    else if (auto reduce_min = as_type_ptr<op::v1::ReduceMin>(reduction_node))
+    {
+        auto reduction_axes = reduce_min->get_reduction_axes();
+        auto input_shape = reduce_min->get_input_shape(0);
+        Shape shape_no_keep_dims;
+        for (size_t i = 0; i < input_shape.size(); i++)
+        {
+            if (reduction_axes.count(i) == 0)
+            {
+                shape_no_keep_dims.push_back(input_shape[i]);
+            }
+        }
+        runtime::reference::min<T>(constant->get_vector<T>().data(),
+                                   out_vec.data(),
+                                   constant->get_output_shape(0),
+                                   shape_no_keep_dims,
+                                   reduce_min->get_reduction_axes());
+    }
     else if (auto prod = as_type_ptr<op::Product>(reduction_node))
     {
         runtime::reference::product<T>(constant->get_vector<T>().data(),
@@ -59,6 +99,24 @@ static shared_ptr<op::Constant>
                                        reduction_node->get_shape(),
                                        prod->get_reduction_axes());
     }
+    else if (auto reduce_prod = as_type_ptr<op::v1::ReduceProd>(reduction_node))
+    {
+        auto reduction_axes = reduce_prod->get_reduction_axes();
+        auto input_shape = reduce_prod->get_input_shape(0);
+        Shape shape_no_keep_dims;
+        for (size_t i = 0; i < input_shape.size(); i++)
+        {
+            if (reduction_axes.count(i) == 0)
+            {
+                shape_no_keep_dims.push_back(input_shape[i]);
+            }
+        }
+        runtime::reference::product<T>(constant->get_vector<T>().data(),
+                                       out_vec.data(),
+                                       constant->get_output_shape(0),
+                                       shape_no_keep_dims,
+                                       reduce_prod->get_reduction_axes());
+    }
     else if (auto sum = as_type_ptr<op::Sum>(reduction_node))
     {
         runtime::reference::sum<T>(constant->get_vector<T>().data(),
@@ -67,6 +125,42 @@ static shared_ptr<op::Constant>
                                    reduction_node->get_shape(),
                                    sum->get_reduction_axes());
     }
+    else if (auto reduce_sum = as_type_ptr<op::v1::ReduceSum>(reduction_node))
+    {
+        auto reduction_axes = reduce_sum->get_reduction_axes();
+        auto input_shape = reduce_sum->get_input_shape(0);
+        Shape shape_no_keep_dims;
+        for (size_t i = 0; i < input_shape.size(); i++)
+        {
+            if (reduction_axes.count(i) == 0)
+            {
+                shape_no_keep_dims.push_back(input_shape[i]);
+            }
+        }
+        runtime::reference::sum<T>(constant->get_vector<T>().data(),
+                                   out_vec.data(),
+                                   constant->get_output_shape(0),
+                                   shape_no_keep_dims,
+                                   reduce_sum->get_reduction_axes());
+    }
+    else if (auto reduce_mean = as_type_ptr<op::v1::ReduceMean>(reduction_node))
+    {
+        auto reduction_axes = reduce_mean->get_reduction_axes();
+        auto input_shape = reduce_mean->get_input_shape(0);
+        Shape shape_no_keep_dims;
+        for (size_t i = 0; i < input_shape.size(); i++)
+        {
+            if (reduction_axes.count(i) == 0)
+            {
+                shape_no_keep_dims.push_back(input_shape[i]);
+            }
+        }
+        runtime::reference::mean<T>(constant->get_vector<T>().data(),
+                                    out_vec.data(),
+                                    constant->get_output_shape(0),
+                                    shape_no_keep_dims,
+                                    reduce_mean->get_reduction_axes());
+    }
     else
     {
         NGRAPH_CHECK(false,
@@ -134,7 +228,12 @@ void pass::ConstantFolding::construct_constant_arithmetic_reduction()
         make_shared<pattern::op::Label>(element::i64, Shape{2}, pattern::has_class<op::Constant>());
     auto is_supported_reduction = [](std::shared_ptr<Node> n) {
         return (pattern::has_class<op::Max>()(n) || pattern::has_class<op::Min>()(n) ||
-                pattern::has_class<op::Product>()(n) || pattern::has_class<op::Sum>()(n));
+                pattern::has_class<op::Product>()(n) || pattern::has_class<op::Sum>()(n) ||
+                pattern::has_class<op::v1::ReduceMax>()(n) ||
+                pattern::has_class<op::v1::ReduceMin>()(n) ||
+                pattern::has_class<op::v1::ReduceProd>()(n) ||
+                pattern::has_class<op::v1::ReduceSum>()(n) ||
+                pattern::has_class<op::v1::ReduceMean>()(n));
     };
     auto reduction =
         std::make_shared<pattern::op::Any>(element::i32,

src/ngraph/runtime/reference/mean.hpp

+//*****************************************************************************
+// Copyright 2017-2019 Intel Corporation
+//
+// 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.
+//*****************************************************************************
+
+#pragma once
+
+#include <cmath>
+
+#include "ngraph/coordinate_transform.hpp"
+#include "ngraph/runtime/reference/sum.hpp"
+#include "ngraph/shape_util.hpp"
+#include "ngraph/type/bfloat16.hpp"
+#include "ngraph/type/float16.hpp"
+
+namespace ngraph
+{
+    namespace runtime
+    {
+        namespace reference
+        {
+            template <typename T>
+            void mean(const T* arg,
+                      T* out,
+                      const Shape& in_shape,
+                      const Shape& out_shape,
+                      const AxisSet& reduction_axes)
+            {
+                CoordinateTransform output_transform(out_shape);
+                std::vector<T> cs(shape_size(out_shape));
+
+                for (const Coordinate& output_coord : output_transform)
+                {
+                    out[output_transform.index(output_coord)] = 0;
+                    cs[output_transform.index(output_coord)] = 0;
+                }
+
+                CoordinateTransform input_transform(in_shape);
+                std::map<size_t, int> index_to_count_map;
+
+                for (const Coordinate& input_coord : input_transform)
+                {
+                    Coordinate output_coord = reduce(input_coord, reduction_axes);
+
+                    T x = arg[input_transform.index(input_coord)];
+                    T& z = out[output_transform.index(output_coord)];
+                    auto index = output_transform.index(output_coord);
+                    if (index_to_count_map.find(index) == index_to_count_map.end())
+                    {
+                        index_to_count_map[index] = 1;
+                    }
+                    else
+                    {
+                        index_to_count_map[index]++;
+                    }
+
+                    if (is_finite(x) && is_finite(z))
+                    {
+                        T& c = cs[output_transform.index(output_coord)];
+                        T t = z + (x - c);
+                        c = (t - z) - (x - c);
+                        z = t;
+                    }
+                    else
+                    {
+                        z = z + x;
+                    }
+                }
+
+                for (const Coordinate& output_coord : output_transform)
+                {
+                    auto count = index_to_count_map[output_transform.index(output_coord)];
+                    out[output_transform.index(output_coord)] =
+                        out[output_transform.index(output_coord)] / count;
+                }
+            }
+        }
+    }
+}