Add more safe points in compiler

runtime/tools/verbose_gc_to_bmu.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 // NOTE: See also wrapper script sdk/runtime/tools/bmu_benchmark_gallery.sh
 //
 // Tool to compute bounded mutator utilization (BMU) from a --verbose_gc log.
 // Outputs CSV suitable for, e.g., gnuplot:
 //
 // dart --verbose_gc foo.dart 2> foo.gclog
@@ skipping 60 matching lines @@
 
   final Interval<int> _run = new Interval<int>(0, 0);
   final List<Interval<int>> _pauses = [];
 }
 
 // Returns a GC pause as an interval in microseconds since program start, or
 // the interval [0, 0) on parse error.
 Interval<int> parseVerboseGCLine(String line) {
   var fields = line.split(',');
   // Update this (and indices below, if needed) when logging format changes.
-  if (fields.length != 25) {
-    assert(line.startsWith('[    GC    |  space  | count | start | gc time') ||
-        line.startsWith('[ (isolate)| (reason)|       |  (s)  |   (ms) '));
+  if (fields.length < 10) {
+    // Ignore the lines that just specify column names, separated by '|'.
+    // We assume these have very few commas in them, so that fields.length
+    // is < 10.
+    assert(line.contains("|"));
     return new Interval<int>(0, 0);
   }
   var begin = (1e6 * double.parse(fields[2])).floor();
   var duration = (1000 * double.parse(fields[3])).floor();
   var end = begin + duration;
   return new Interval<int>(begin, end);
 }
 
 void main() {
   Timeline t = new Timeline();
   for (String line = stdin.readLineSync();
       line != null;
       line = stdin.readLineSync()) {
     t.addPause(parseVerboseGCLine(line));
   }
   print('# window_size_ms, bounded_mutator_utilization');
   var minimumSeen = 1.0;
   for (int w = t._run.length;
       w > 1000 * MINIMUM_WINDOW_SIZE_MS;
       w = (w * WINDOW_STEP_FACTOR).floor()) {
     minimumSeen = min(minimumSeen, t.minUtilization(w));
     print('${w / 1000}, $minimumSeen');
   }
 }