Add a percentage to each metric in the V8 timeline plot

tools/plot-timer-events.js

 // Copyright 2012 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
@@ skipping 482 matching lines @@
         " enhanced font 'Helvetica,10'");
   print("set yrange [0:" + (num_timer_event + 1) + "]");
   print("set xlabel \"execution time in ms\"");
   print("set xrange [" + xrange_start + ":" + xrange_end + "]");
   print("set style fill pattern 2 bo 1");
   print("set style rect fs solid 1 noborder");
   print("set style line 1 lt 1 lw 1 lc rgb \"#000000\"");
   print("set xtics out nomirror");
   print("unset key");
 
+  var percentages = {};
+  var total = 0;
+  for (var name in TimerEvents) {
+    var event = TimerEvents[name];
+    var ranges = MergeRanges(event.ranges);
+    var exclude_ranges = [new Range(-Infinity, xrange_start),
+                          new Range(xrange_end, Infinity)];
+    ranges = ExcludeRanges(ranges, exclude_ranges);
+    var sum = 0;
+    for (var i = 0; i < ranges.length; i++) {
+      sum += ranges[i].end - ranges[i].start;
+    }
+    percentages[name] = (sum / (xrange_end - xrange_start) * 100).toFixed(1);
+  }
+
   // Name Y-axis.
   var ytics = [];
   for (name in TimerEvents) {
     var index = TimerEvents[name].index;
-    ytics.push('"' + name + '"' + ' ' + index);
+    ytics.push('"' + name + ' (' + percentages[name] + '%%)" ' + index);
   }
   ytics.push('"code kind being executed"' + ' ' + (kY1Offset - 1));
   ytics.push('"top ' + kStackFrames + ' js stack frames"' + ' ' +
              (kY1Offset - 2));
   ytics.push('"pause times" 0');
   print("set ytics out nomirror (" + ytics.join(', ') + ")");
 
   // Plot timeline.
   for (var name in TimerEvents) {
     var event = TimerEvents[name];
@@ skipping 68 matching lines @@
   for (var i = 0; i < execution_pauses.length; i++) {
     var pause = execution_pauses[i];
     print(pause.end + " " + pause.duration());
   }
   print("e");
 }
 
 
 CollectData();
 GnuplotOutput();