Revert "Temporarily disable performance.now() in the d8 shell."

This reverts commit r18529.

R=hpayer@chromium.org

Review URL: https://codereview.chromium.org/133523003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18531 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/d8.cc

@@ -159,6 +159,7 @@ i::OS::MemoryMappedFile* Shell::counters_file_ = NULL;
 CounterCollection Shell::local_counters_;
 CounterCollection* Shell::counters_ = &local_counters_;
 i::Mutex Shell::context_mutex_;
+const i::TimeTicks Shell::kInitialTicks = i::TimeTicks::HighResolutionNow();
 Persistent<Context> Shell::utility_context_;
 #endif  // V8_SHARED
 
@@ -287,6 +288,15 @@ int PerIsolateData::RealmFind(Handle<Context> context) {
 }
 
 
+#ifndef V8_SHARED
+// performance.now() returns a time stamp as double, measured in milliseconds.
+void Shell::PerformanceNow(const v8::FunctionCallbackInfo<v8::Value>& args) {
+  i::TimeDelta delta = i::TimeTicks::HighResolutionNow() - kInitialTicks;
+  args.GetReturnValue().Set(delta.InMillisecondsF());
+}
+#endif  // V8_SHARED
+
+
 // Realm.current() returns the index of the currently active realm.
 void Shell::RealmCurrent(const v8::FunctionCallbackInfo<v8::Value>& args) {
   Isolate* isolate = args.GetIsolate();
@@ -886,6 +896,14 @@ Handle<ObjectTemplate> Shell::CreateGlobalTemplate(Isolate* isolate) {
                               RealmSharedGet, RealmSharedSet);
   global_template->Set(String::NewFromUtf8(isolate, "Realm"), realm_template);
 
+#ifndef V8_SHARED
+  Handle<ObjectTemplate> performance_template = ObjectTemplate::New(isolate);
+  performance_template->Set(String::NewFromUtf8(isolate, "now"),
+                            FunctionTemplate::New(isolate, PerformanceNow));
+  global_template->Set(String::NewFromUtf8(isolate, "performance"),
+                       performance_template);
+#endif  // V8_SHARED
+
 #if !defined(V8_SHARED) && !defined(_WIN32) && !defined(_WIN64)
   Handle<ObjectTemplate> os_templ = ObjectTemplate::New(isolate);
   AddOSMethods(isolate, os_templ);

src/d8.h

@@ -300,6 +300,8 @@ class Shell : public i::AllStatic {
                                                 Handle<String> command);
   static void DispatchDebugMessages();
 #endif  // ENABLE_DEBUGGER_SUPPORT
+
+  static void PerformanceNow(const v8::FunctionCallbackInfo<v8::Value>& args);
 #endif  // V8_SHARED
 
   static void RealmCurrent(const v8::FunctionCallbackInfo<v8::Value>& args);
@@ -392,6 +394,7 @@ class Shell : public i::AllStatic {
   static CounterCollection* counters_;
   static i::OS::MemoryMappedFile* counters_file_;
   static i::Mutex context_mutex_;
+  static const i::TimeTicks kInitialTicks;
 
   static Counter* GetCounter(const char* name, bool is_histogram);
   static void InstallUtilityScript(Isolate* isolate);

test/mjsunit/d8-performance-now.js

@@ -0,0 +1,62 @@
+// Copyright 2013 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --allow-natives-syntax
+
+// Test the performance.now() function of d8.  This test only makes sense with
+// d8.
+
+// Don't run this test in gc stress mode. Time differences may be long
+// due to garbage collections.
+%SetFlags("--gc-interval=-1");
+%SetFlags("--nostress-compaction");
+
+if (this.performance && performance.now) {
+  (function run() {
+    var start_test = performance.now();
+    // Let the retry run for maximum 100ms to reduce flakiness.
+    for (var start = performance.now();
+        start - start_test < 100;
+        start = performance.now()) {
+      var end = performance.now();
+      assertTrue(start >= start_test);
+      assertTrue(end >= start);
+      while (end - start == 0) {
+        var next = performance.now();
+        assertTrue(next >= end);
+        end = next;
+      }
+      if (end - start <= 1) {
+        // Found (sub-)millisecond granularity.
+        return;
+      } else {
+        print("Timer difference too big: " + (end - start) + "ms");
+      }
+    }
+    assertTrue(false);
+  })()
+}

test/mjsunit/mjsunit.status

@@ -63,6 +63,11 @@
   # Only regexp stuff tested, no need for extensive Crankshaft tests.
   'regexp-global': [PASS, NO_VARIANTS],
 
+  ##############################################################################
+  # No need to waste time for this test.
+  'd8-performance-now': [PASS, NO_VARIANTS],
+
+  ##############################################################################
   # These use a built-in that's only present in debug mode. They take
   # too long to run in debug mode on ARM and MIPS.
   'fuzz-natives-part*': [PASS, ['mode == release or arch == arm or arch == android_arm or arch == mipsel', SKIP]],