Implement nativePerformanceNow to improve Profiler API results

Libraries/polyfills/performance.js

@@ -0,0 +1,24 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ * @flow strict
+ * @polyfill
+ */
+
+if (!global.performance) {
+  global.performance = {};
+}
+
+/**
+ * Returns a double, measured in milliseconds.
+ * https://developer.mozilla.org/en-US/docs/Web/API/Performance/now
+ */
+if (typeof global.performance !== 'function') {
+  global.performance.now = function() {
+    return global.nativePerformanceNow();
+  };
+}

React/CxxBridge/JSCExecutorFactory.mm

@@ -25,6 +25,13 @@
         [NSString stringWithUTF8String:message.c_str()]);
     };
     react::bindNativeLogger(runtime, iosLoggingBinder);
+
+    react::PerformanceNow iosPerformanceNowBinder =[]() {
+        // CACurrentMediaTime() returns the current absolute time, in seconds
+        return CACurrentMediaTime() * 1000;
+    };
+    react::bindNativePerformanceNow(runtime, iosPerformanceNowBinder);
+
     // Wrap over the original runtimeInstaller
     if (runtimeInstaller) {
       runtimeInstaller(runtime);

ReactAndroid/src/main/java/com/facebook/hermes/reactexecutor/OnLoad.cpp

@@ -14,6 +14,7 @@
 #include <react/jni/JReactMarker.h>
 #include <react/jni/JSLogging.h>
 #include <react/jni/JavaScriptExecutorHolder.h>
+#include <react/jni/NativeTime.h>
 
 #include <memory>
 
@@ -47,6 +48,11 @@ static void installBindings(jsi::Runtime &runtime) {
       static_cast<void (*)(const std::string &, unsigned int)>(
           &reactAndroidLoggingHook);
   react::bindNativeLogger(runtime, androidLogger);
+
+  react::PerformanceNow androidNativePerformanceNow =
+       static_cast<double (*)()>(
+          &reactAndroidNativePerformanceNowHook);
+  react::bindNativePerformanceNow(runtime, androidNativePerformanceNow);
 }
 
 class HermesExecutorHolder

ReactAndroid/src/main/java/com/facebook/react/jscexecutor/OnLoad.cpp

@@ -12,6 +12,7 @@
 #include <react/jni/JSLogging.h>
 #include <react/jni/JavaScriptExecutorHolder.h>
 #include <react/jni/ReadableNativeMap.h>
+#include <react/jni/NativeTime.h>
 
 #include <memory>
 
@@ -30,6 +31,11 @@ class JSCExecutorFactory : public JSExecutorFactory {
           static_cast<void (*)(const std::string &, unsigned int)>(
               &reactAndroidLoggingHook);
       react::bindNativeLogger(runtime, androidLogger);
+
+      react::PerformanceNow androidNativePerformanceNow =
+          static_cast<double (*)()>(
+              &reactAndroidNativePerformanceNowHook);
+      react::bindNativePerformanceNow(runtime, androidNativePerformanceNow);
     };
     return std::make_unique<JSIExecutor>(
         jsc::makeJSCRuntime(),

ReactAndroid/src/main/jni/react/jni/NativeTime.cpp

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include <time.h>
+#include "NativeTime.h"
+
+namespace facebook {
+namespace react {
+
+double reactAndroidNativePerformanceNowHook() {
+  struct timespec now;
+  clock_gettime(CLOCK_MONOTONIC, &now);
+
+  return (now.tv_sec * 1000000000LL + now.tv_nsec) / 1000000.0;
+}
+
+} // namespace react
+} // namespace facebook

ReactAndroid/src/main/jni/react/jni/NativeTime.h

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+namespace facebook {
+namespace react {
+
+double reactAndroidNativePerformanceNowHook();
+
+} // namespace react
+} // namespace facebook

ReactCommon/jsiexecutor/jsireact/JSIExecutor.cpp

@@ -417,5 +417,22 @@ void bindNativeLogger(Runtime &runtime, Logger logger) {
           }));
 }
 
+void bindNativePerformanceNow(Runtime &runtime, PerformanceNow performanceNow) {
+  runtime.global().setProperty(
+        runtime,
+        "nativePerformanceNow",
+        Function::createFromHostFunction(
+            runtime,
+            PropNameID::forAscii(runtime, "nativePerformanceNow"),
+            0,
+            [performanceNow = std::move(performanceNow)](
+                jsi::Runtime &runtime,
+                const jsi::Value &,
+                const jsi::Value *args,
+                size_t count) {
+                return Value(performanceNow());
+            }));
+}
+
 } // namespace react
 } // namespace facebook

ReactCommon/jsiexecutor/jsireact/JSIExecutor.h

@@ -135,5 +135,8 @@ class JSIExecutor : public JSExecutor {
 using Logger =
     std::function<void(const std::string &message, unsigned int logLevel)>;
 void bindNativeLogger(jsi::Runtime &runtime, Logger logger);
+
+using PerformanceNow = std::function<double()>;
+void bindNativePerformanceNow(jsi::Runtime &runtime, PerformanceNow performanceNow);
 } // namespace react
 } // namespace facebook

rn-get-polyfills.js

@@ -13,4 +13,5 @@ module.exports = () => [
   require.resolve('./Libraries/polyfills/console.js'),
   require.resolve('./Libraries/polyfills/error-guard.js'),
   require.resolve('./Libraries/polyfills/Object.es7.js'),
+  require.resolve('./Libraries/polyfills/performance.js'),
 ];