Add global setting control TF32 execution

tensorflow/core/platform/BUILD

@@ -938,6 +938,13 @@ cc_library(
     alwayslink = 1,
 )
 
+cc_library(
+    name = "tf32_utils",
+    srcs = ["tf32_utils.cc"],
+    hdrs = ["tf32_utils.h"],
+    copts = tf_copts(),
+)
+
 tf_cc_tests(
     name = "low_level_library_tests",
     size = "small",

tensorflow/core/platform/tf32_utils.cc

@@ -0,0 +1,27 @@
+/* Copyright 2020 The TensorFlow 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.
+==============================================================================*/
+
+#include "tensorflow/core/platform/tf32_utils.h"
+
+namespace tensorflow {
+
+// TODO(nluehr): enable tf32 execution by default after TF32 Ampere testing.
+static bool tf32_enabled = false;
+
+void allow_tf32_execution(bool allow) { tf32_enabled = allow; }
+
+bool tf32_execution_allowed() { return tf32_enabled; }
+
+}  // namespace tensorflow

tensorflow/core/platform/tf32_utils.h

@@ -0,0 +1,27 @@
+/* Copyright 2020 The TensorFlow 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.
+==============================================================================*/
+
+#ifndef TENSORFLOW_CORE_PLATFORM_TF32_UTILS_H_
+#define TENSORFLOW_CORE_PLATFORM_TF32_UTILS_H_
+
+namespace tensorflow {
+
+void allow_tf32_execution(bool allow);
+
+bool tf32_execution_allowed();
+
+}  // namespace tensorflow
+
+#endif  // TENSORFLOW_CORE_PLATFORM_TF32_UTILS_H_