PROFILE_MAIN_LOOP option

2 files changed, 20 insertions, 0 deletions

diff --git a/src/library_browser.js b/src/library_browser.js
index f285a6d2..d0fdeef0 100644
--- a/src/library_browser.js
+++ b/src/library_browser.js
@@ -10,6 +10,10 @@ mergeInto(LibraryManager.library, {
   $Browser: {
     mainLoop: {
       scheduler: null,
+#if PROFILE_MAIN_LOOP
+      meanTime: 0,
+      lastReport: 0,
+#endif
       shouldPause: false,
       paused: false,
       queue: [],
@@ -394,7 +398,21 @@ mergeInto(LibraryManager.library, {
         Browser.mainLoop.shouldPause = false;
         return;
       }
+
+#if PROFILE_MAIN_LOOP
+      var start = performance.now();
+#endif
       jsFunc();
+#if PROFILE_MAIN_LOOP
+      var now = performance.now();
+      var time = now - start;
+      Browser.mainLoop.meanTime = (Browser.mainLoop.meanTime*9 + time)/10;
+      if (now - Browser.mainLoop.lastReport > 1000) {
+        console.log('main loop time: ' + Browser.mainLoop.meanTime);
+        Browser.mainLoop.lastReport = now;
+      }
+#endif
+
       if (Browser.mainLoop.shouldPause) {
         // catch pauses from the main loop itself
         Browser.mainLoop.paused = true;
diff --git a/src/settings.js b/src/settings.js
index 09b17c83..75b30003 100644
--- a/src/settings.js
+++ b/src/settings.js
@@ -115,6 +115,8 @@ var LIBRARY_DEBUG = 0; // Print out when we enter a library call (library*.js).
 var GL_DEBUG = 0; // Print out all calls into WebGL. As with LIBRARY_DEBUG, you can set a runtime
                   // option, in this case GL.debug.
 
+var PROFILE_MAIN_LOOP = 0; // Profile the function called in set_main_loop
+
 var DISABLE_EXCEPTION_CATCHING = 0; // Disables generating code to actually catch exceptions. If the code you
                                     // are compiling does not actually rely on catching exceptions (but the
                                     // compiler generates code for it, maybe because of stdlibc++ stuff),