Merge "Cache the most-recently used timezone for mktime_tz and localtime_tz."

tests/Android.mk

@@ -32,6 +32,7 @@ benchmark_src_files = \
     benchmark_main.cpp \
     math_benchmark.cpp \
     string_benchmark.cpp \
+    time_benchmark.cpp \
 
 # Build benchmarks for the device (with bionic's .so). Run with:
 #   adb shell bionic-benchmarks

tests/time_benchmark.cpp

@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * 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 "benchmark.h"
+
+#include <time.h>
+
+#if defined(__BIONIC__)
+
+// Used by the horrible android.text.format.Time class, which is used by Calendar. http://b/8270865.
+extern "C" void localtime_tz(const time_t* const timep, struct tm* tmp, const char* tz);
+
+static void BM_time_localtime_tz(int iters) {
+  StartBenchmarkTiming();
+
+  time_t now(time(NULL));
+  tm broken_down_time;
+  for (int i = 0; i < iters; ++i) {
+    localtime_tz(&now, &broken_down_time, "Europe/Berlin");
+  }
+
+  StopBenchmarkTiming();
+}
+BENCHMARK(BM_time_localtime_tz);
+#endif