ART: Add three Timer functions

Add support for GetAvailableProcessors, GetTimerInfo and GetTime.
Add tests.

Bug: 31455788
Test: m test-art-host-run-test-926-timers
Change-Id: I9629654349787e27dee686284567b5de70e138f2
diff --git a/test/927-timers/timers.cc b/test/927-timers/timers.cc
new file mode 100644
index 0000000..58d5c27
--- /dev/null
+++ b/test/927-timers/timers.cc
@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2017 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 <inttypes.h>
+
+#include "android-base/stringprintf.h"
+#include "base/logging.h"
+#include "base/macros.h"
+#include "jni.h"
+#include "openjdkjvmti/jvmti.h"
+
+#include "ti-agent/common_helper.h"
+#include "ti-agent/common_load.h"
+
+namespace art {
+namespace Test926Timers {
+
+extern "C" JNIEXPORT jint JNICALL Java_Main_getAvailableProcessors(
+    JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED) {
+  jint count;
+  jvmtiError result = jvmti_env->GetAvailableProcessors(&count);
+  if (JvmtiErrorToException(env, result)) {
+    return -1;
+  }
+  return count;
+}
+
+extern "C" JNIEXPORT jlong JNICALL Java_Main_getTime(
+    JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED) {
+  jlong time;
+  jvmtiError result = jvmti_env->GetTime(&time);
+  if (JvmtiErrorToException(env, result)) {
+    return -1;
+  }
+  return time;
+}
+
+extern "C" JNIEXPORT jobjectArray JNICALL Java_Main_getTimerInfo(
+    JNIEnv* env, jclass Main_klass ATTRIBUTE_UNUSED) {
+  jvmtiTimerInfo info;
+  jvmtiError result = jvmti_env->GetTimerInfo(&info);
+  if (JvmtiErrorToException(env, result)) {
+    return nullptr;
+  }
+
+  auto callback = [&](jint index) -> jobject {
+    switch (index) {
+      // Max value.
+      case 0:
+        return env->NewStringUTF(android::base::StringPrintf("%" PRId64, info.max_value).c_str());
+
+      // Skip forward.
+      case 1:
+        return env->NewStringUTF(info.may_skip_forward == JNI_TRUE ? "true" : "false");
+      // Skip backward.
+      case 2:
+        return env->NewStringUTF(info.may_skip_forward == JNI_TRUE ? "true" : "false");
+
+      // The kind.
+      case 3:
+        return env->NewStringUTF(
+            android::base::StringPrintf("%d", static_cast<jint>(info.kind)).c_str());
+    }
+    LOG(FATAL) << "Should not reach here";
+    UNREACHABLE();
+  };
+  return CreateObjectArray(env, 4, "java/lang/Object", callback);
+}
+
+}  // namespace Test926Timers
+}  // namespace art