Elementwise sign operation (#201)

* Elementwise sign operation

* Formatting

src/ngraph/ngraph.hpp

@@ -84,6 +84,7 @@
 #include "ngraph/ops/remainder.hpp"
 #include "ngraph/ops/reshape.hpp"
 #include "ngraph/ops/select.hpp"
+#include "ngraph/ops/sign.hpp"
 #include "ngraph/ops/sin.hpp"
 #include "ngraph/ops/sinh.hpp"
 #include "ngraph/ops/slice.hpp"

src/ngraph/ops/sign.hpp

+// ----------------------------------------------------------------------------
+// Copyright 2017 Nervana Systems Inc.
+// 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
+// ----------------------------------------------------------------------------
+
+#pragma once
+
+#include "ngraph/ops/op.hpp"
+
+namespace ngraph
+{
+    namespace op
+    {
+        class Sign : public UnaryElementwiseArithmetic
+        {
+        public:
+            Sign(const std::shared_ptr<Node>& arg)
+                : UnaryElementwiseArithmetic(arg)
+            {
+            }
+
+            virtual std::string description() const override { return "Sign"; }
+        };
+    }
+}

src/ngraph/runtime/ngvm/eigen/sign.hpp

+// ----------------------------------------------------------------------------
+// Copyright 2017 Nervana Systems Inc.
+// 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
+// ----------------------------------------------------------------------------
+
+#pragma once
+
+#include "ngraph/runtime/ngvm/call_frame.hpp"
+#include "ngraph/runtime/ngvm/eigen/utils.hpp"
+#include "ngraph/runtime/ngvm/instruction.hpp"
+#include "ngraph/runtime/tensor_view.hpp"
+
+namespace ngraph
+{
+    namespace runtime
+    {
+        namespace ngvm
+        {
+            namespace eigen
+            {
+                template <typename ET>
+                class SignInstruction : public Instruction
+                {
+                public:
+                    SignInstruction(TensorViewInfo arg, TensorViewInfo out)
+                        : m_arg(arg)
+                        , m_out(out)
+                    {
+                    }
+
+                    virtual void execute(CallFrame& call_frame) const override
+                    {
+                        EigenArray1d<ET, fmt::V>(call_frame, m_out) =
+                            EigenArray1d<ET, fmt::V>(call_frame, m_arg).sign();
+                    }
+
+                protected:
+                    TensorViewInfo m_arg;
+                    TensorViewInfo m_out;
+                };
+            }
+        }
+    }
+}

src/ngraph/runtime/ngvm/external_function.cpp

@@ -52,6 +52,7 @@
 #include "ngraph/ops/reduce.hpp"
 #include "ngraph/ops/reshape.hpp"
 #include "ngraph/ops/select.hpp"
+#include "ngraph/ops/sign.hpp"
 #include "ngraph/ops/sin.hpp"
 #include "ngraph/ops/sinh.hpp"
 #include "ngraph/ops/slice.hpp"
@@ -103,6 +104,7 @@
 #include "ngraph/runtime/ngvm/eigen/return.hpp"
 #include "ngraph/runtime/ngvm/eigen/scalar_tensor_product.hpp"
 #include "ngraph/runtime/ngvm/eigen/select.hpp"
+#include "ngraph/runtime/ngvm/eigen/sign.hpp"
 #include "ngraph/runtime/ngvm/eigen/sin.hpp"
 #include "ngraph/runtime/ngvm/eigen/sinh.hpp"
 #include "ngraph/runtime/ngvm/eigen/subtract.hpp"
@@ -353,6 +355,7 @@ ExternalFunction::OpMap& ExternalFunction::get_op_map()
         REGISTER_NUMERIC_UNOP(op::Exp, eigen::ExpInstruction);
         REGISTER_NUMERIC_UNOP(op::Log, eigen::LogInstruction);
         REGISTER_NUMERIC_UNOP(op::Negative, eigen::NegateInstruction);
+        REGISTER_NUMERIC_UNOP(op::Sign, eigen::SignInstruction);
         REGISTER_NUMERIC_UNOP(op::Sin, eigen::SinInstruction);
         REGISTER_NUMERIC_UNOP(op::Sinh, eigen::SinhInstruction);
         REGISTER_NUMERIC_UNOP(op::Tan, eigen::TanInstruction);

test/execute.cpp

@@ -2478,3 +2478,24 @@ TEST(execute, sum_matrix_to_scalar_zero_by_zero)
     // input tensors, so let's do this too.
     ASSERT_EQ((vector<float>{}), a->get_vector());
 }
+
+TEST(execute, sign)
+{
+    auto shape = Shape{2, 3};
+    auto A = make_shared<op::Parameter>(element::Float32::element_type(), shape);
+    auto result_type = make_shared<TensorViewType>(element::Float32::element_type(), shape);
+    auto f = make_shared<Function>(make_shared<op::Sign>(A), result_type, op::Parameters{A});
+
+    auto manager = runtime::Manager::get("NGVM");
+    auto external = manager->compile(f);
+    auto backend = manager->allocate_backend();
+    auto cf = backend->make_call_frame(external);
+
+    // Create some tensors for input/output
+    auto a = backend->make_parameterized_tensor_view<element::Float32>(shape);
+    *a = vector<float>{1, -2, 0, -4.8f, 4.8f, -0.0};
+    auto result = backend->make_parameterized_tensor_view<element::Float32>(shape);
+
+    (*cf)({a}, {result});
+    ASSERT_EQ((vector<float>{1, -1, 0, -1, 1, 0}), result->get_vector());
+}