From a935731bd3e01fcd753b1224b70ed9c8b4c2eb49 Mon Sep 17 00:00:00 2001
From: Sherlock <baihan.huang@gmail.com>
Date: Wed, 2 Sep 2020 15:54:17 -0700
Subject: [PATCH] Neg Gradient (#5022)

Co-authored-by: Sherlock Huang <bahuang@OrtTrainingDev3.af05slrtruoetgaxwwjv5nsq5e.px.internal.cloudapp.net>
---
 orttraining/orttraining/core/graph/gradient_builder.cc       | 5 +++++
 orttraining/orttraining/core/graph/gradient_builder.h        | 1 +
 .../orttraining/core/graph/gradient_builder_registry.cc      | 1 +
 orttraining/orttraining/test/gradient/gradient_ops_test.cc   | 4 ++++
 4 files changed, 11 insertions(+)

diff --git a/orttraining/orttraining/core/graph/gradient_builder.cc b/orttraining/orttraining/core/graph/gradient_builder.cc
index 2440299ede..ba26ccc8af 100644
--- a/orttraining/orttraining/core/graph/gradient_builder.cc
+++ b/orttraining/orttraining/core/graph/gradient_builder.cc
@@ -1028,6 +1028,11 @@ IMPLEMENT_GRADIENT_BUILDER(GetDivGradient) {
   }
 }
 
+IMPLEMENT_GRADIENT_BUILDER(GetNegGradient) {
+  return std::vector<NodeDef>{
+      NodeDef("Neg", {GO(0)}, {GI(0)})};
+}
+
 IMPLEMENT_GRADIENT_BUILDER(GetReduceMeanGradient) {
   std::vector<NodeDef> result;
   auto attributes = SrcNodeAttributes();
diff --git a/orttraining/orttraining/core/graph/gradient_builder.h b/orttraining/orttraining/core/graph/gradient_builder.h
index 340cf8e5e8..02282a643f 100644
--- a/orttraining/orttraining/core/graph/gradient_builder.h
+++ b/orttraining/orttraining/core/graph/gradient_builder.h
@@ -24,6 +24,7 @@ DECLARE_GRADIENT_BUILDER(GetReluGradient)
 DECLARE_GRADIENT_BUILDER(GetAddSubGradient)
 DECLARE_GRADIENT_BUILDER(GetMulGradient)
 DECLARE_GRADIENT_BUILDER(GetDivGradient)
+DECLARE_GRADIENT_BUILDER(GetNegGradient)
 DECLARE_GRADIENT_BUILDER(GetReduceMeanGradient)
 DECLARE_GRADIENT_BUILDER(GetReduceSumGradient)
 DECLARE_GRADIENT_BUILDER(GetReduceLogSumExpGradient)
diff --git a/orttraining/orttraining/core/graph/gradient_builder_registry.cc b/orttraining/orttraining/core/graph/gradient_builder_registry.cc
index 6cd85c13d2..11ef5ec6b8 100644
--- a/orttraining/orttraining/core/graph/gradient_builder_registry.cc
+++ b/orttraining/orttraining/core/graph/gradient_builder_registry.cc
@@ -60,6 +60,7 @@ void GradientBuilderRegistry::RegisterGradientBuilders() {
   REGISTER_GRADIENT_BUILDER("Sub", GetAddSubGradient);
   REGISTER_GRADIENT_BUILDER("Mul", GetMulGradient);
   REGISTER_GRADIENT_BUILDER("Div", GetDivGradient);
+  REGISTER_GRADIENT_BUILDER("Neg", GetNegGradient);
   REGISTER_GRADIENT_BUILDER("Concat", GetConcatGradient);
   REGISTER_GRADIENT_BUILDER("ConcatTraining", GetConcatTrainingGradient);
   REGISTER_GRADIENT_BUILDER("Reshape", GetReshapeGradient);
diff --git a/orttraining/orttraining/test/gradient/gradient_ops_test.cc b/orttraining/orttraining/test/gradient/gradient_ops_test.cc
index c1c84ae41f..8e12312071 100644
--- a/orttraining/orttraining/test/gradient/gradient_ops_test.cc
+++ b/orttraining/orttraining/test/gradient/gradient_ops_test.cc
@@ -395,6 +395,10 @@ TEST(GradientCheckerTest, SinGrad) {
   UnaryOpGradientTest("Sin");
 }
 
+TEST(GradientCheckerTest, NegGrad) {
+  UnaryOpGradientTest("Neg");
+}
+
 TEST(GradientCheckerTest, LogGrad) {
   TensorShape shape({2,5,6});