Undeprecate tensorflow::StringPiece and move it under core/platform

PiperOrigin-RevId: 262283279

tensorflow/core/BUILD

@@ -670,6 +670,7 @@ cc_library(
         "//tensorflow/core/platform:macros.h",
         "//tensorflow/core/platform:platform.h",
         "//tensorflow/core/platform:protobuf.h",
+        "//tensorflow/core/platform:stringpiece.h",
         "//tensorflow/core/platform:tstring.h",
         "//tensorflow/core/platform:types.h",
         "//tensorflow/core/platform:windows/cpu_info.h",
@@ -679,11 +680,12 @@ cc_library(
         ":platform_base",
         "@com_google_absl//absl/strings",
         "@double_conversion//:double-conversion",
-        "//tensorflow/core/platform:macros",
-        "//tensorflow/core/platform:logging",
-        "//tensorflow/core/platform:platform",
-        "//tensorflow/core/platform:types",
         "//tensorflow/core/platform:cpu_info",
+        "//tensorflow/core/platform:logging",
+        "//tensorflow/core/platform:macros",
+        "//tensorflow/core/platform:platform",
+        "//tensorflow/core/platform:stringpiece",
+        "//tensorflow/core/platform:types",
     ],
 )
 
@@ -765,6 +767,7 @@ cc_library(
     visibility = ["//visibility:public"],
     deps = [
         ":lib_internal",
+        "//tensorflow/core/platform:stringpiece",
         "@com_google_absl//absl/container:inlined_vector",
         "@com_google_absl//absl/strings",
         "@com_google_absl//absl/types:optional",
@@ -810,16 +813,13 @@ cc_library(
     ],
 )
 
-# Libraries that will eventually be moved into lib/core
-# Note that stringpiece_test can't be place here yet, because we are
-# required to use tf_cc_test, and that rule will change / into _
+# DEPRECATED: use platform:stringpiece instead.
 cc_library(
     name = "core_stringpiece",
     hdrs = ["lib/core/stringpiece.h"],
     copts = tf_copts(),
     deps = [
-        ":platform_base",
-        "@com_google_absl//absl/strings",
+        "//tensorflow/core/platform:stringpiece",
     ],
 )
 
@@ -2627,12 +2627,15 @@ cc_library(
         "//tensorflow/core/platform:macros.h",
         "//tensorflow/core/platform:mem.h",
         "//tensorflow/core/platform:platform.h",
+        "//tensorflow/core/platform:stringpiece.h",
         "//tensorflow/core/platform:tstring.h",
         "//tensorflow/core/platform:types.h",
     ],
     copts = tf_copts(),
     linkopts = ["-ldl"],
     deps = [
+        ":core_stringpiece",
+        "//tensorflow/core/platform:stringpiece",
         "//tensorflow/core/platform/default/build_config:jpeg",
         "//tensorflow/core/platform/default/build_config:logging",
         "@com_google_absl//absl/base:core_headers",
@@ -3755,7 +3758,6 @@ tf_cc_tests(
         "lib/core/notification_test.cc",
         "lib/core/refcount_test.cc",
         "lib/core/status_test.cc",
-        "lib/core/stringpiece_test.cc",
         "lib/core/threadpool_test.cc",
         "lib/gtl/cleanup_test.cc",
         "lib/gtl/compactptrset_test.cc",
@@ -3805,6 +3807,7 @@ tf_cc_tests(
         "//tensorflow/core/platform:port_test.cc",
         "//tensorflow/core/platform:profile_utils/cpu_utils_test.cc",
         "//tensorflow/core/platform:stacktrace_handler_test.cc",
+        "//tensorflow/core/platform:stringpiece_test.cc",
         "//tensorflow/core/platform:subprocess_test.cc",
         "//tensorflow/core/platform:vmodule_benchmark_test.cc",
     ],
@@ -3816,6 +3819,7 @@ tf_cc_tests(
         ":protos_all_cc",
         ":test",
         ":test_main",
+        "//tensorflow/core/platform:stringpiece",
         "//third_party/eigen3",
         "@com_google_absl//absl/strings",
         "@com_google_absl//absl/synchronization",

tensorflow/core/lib/core/stringpiece.h

@@ -26,13 +26,6 @@ limitations under the License.
 #ifndef TENSORFLOW_CORE_LIB_CORE_STRINGPIECE_H_
 #define TENSORFLOW_CORE_LIB_CORE_STRINGPIECE_H_
 
-#include "absl/strings/string_view.h"
-
-namespace tensorflow {
-
-// Deprecated: please use absl::string_view directly.
-using StringPiece = absl::string_view;
-
-}  // namespace tensorflow
+#include "tensorflow/core/platform/stringpiece.h"
 
 #endif  // TENSORFLOW_CORE_LIB_CORE_STRINGPIECE_H_

tensorflow/core/platform/BUILD

@@ -160,6 +160,14 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "stringpiece",
+    hdrs = ["stringpiece.h"],
+    deps = [
+        "@com_google_absl//absl/strings",
+    ],
+)
+
 cc_library(
     name = "tstring",
     hdrs = ["tstring.h"],

tensorflow/core/platform/stringpiece.h

@@ -0,0 +1,37 @@
+/* Copyright 2015 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.
+==============================================================================*/
+
+// StringPiece is a simple structure containing a pointer into some external
+// storage and a size.  The user of a StringPiece must ensure that the slice
+// is not used after the corresponding external storage has been
+// deallocated.
+//
+// Multiple threads can invoke const methods on a StringPiece without
+// external synchronization, but if any of the threads may call a
+// non-const method, all threads accessing the same StringPiece must use
+// external synchronization.
+
+#ifndef TENSORFLOW_CORE_PLATFORM_STRINGPIECE_H_
+#define TENSORFLOW_CORE_PLATFORM_STRINGPIECE_H_
+
+#include "absl/strings/string_view.h"
+
+namespace tensorflow {
+
+using StringPiece = absl::string_view;
+
+}  // namespace tensorflow
+
+#endif  // TENSORFLOW_CORE_PLATFORM_STRINGPIECE_H_

tensorflow/core/platform/stringpiece_test.cc

@@ -13,9 +13,10 @@ See the License for the specific language governing permissions and
 limitations under the License.
 ==============================================================================*/
 
-#include "tensorflow/core/lib/core/stringpiece.h"
+#include "tensorflow/core/platform/stringpiece.h"
 
 #include <unordered_map>
+
 #include "tensorflow/core/platform/test.h"
 
 namespace tensorflow {