[tick processor] Introduce --pairwise-timed-range processing mode

tools/logreader.js

 // Copyright 2011 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 18 matching lines @@
  * @fileoverview Log Reader is used to process log file produced by V8.
  */
 
 
 /**
  * Base class for processing log files.
  *
  * @param {Array.<Object>} dispatchTable A table used for parsing and processing
  *     log records.
  * @param {boolean} timedRange Ignore ticks outside timed range.
+ * @param {boolean} pairwiseTimedRange Ignore ticks outside pairs of timer
+ *     markers.
  * @constructor
  */
-function LogReader(dispatchTable, timedRange) {
+function LogReader(dispatchTable, timedRange, pairwiseTimedRange) {
   /**
    * @type {Array.<Object>}
    */
   this.dispatchTable_ = dispatchTable;
 
   /**
    * @type {boolean}
    */
   this.timedRange_ = timedRange;
 
   /**
+   * @type {boolean}
+   */
+  this.pairwiseTimedRange_ = pairwiseTimedRange;
+  if (pairwiseTimedRange) {
+    this.timedRange_ = true;
+  }
+
+  /**
    * Current line.
    * @type {number}
    */
   this.lineNum_ = 0;
 
   /**
    * CSV lines parser.
    * @type {CsvParser}
    */
   this.csvParser_ = new CsvParser();
@@ skipping 39 matching lines @@
  */
 LogReader.prototype.processLogLine = function(line) {
   if (!this.timedRange_) {
     this.processLog_([line]);
     return;
   }
   if (line.startsWith("current-time")) {
     if (this.hasSeenTimerMarker_) {
       this.processLog_(this.logLinesSinceLastTimerMarker_);
       this.logLinesSinceLastTimerMarker_ = [];
+      // In pairwise mode, a "current-time" line ends the timed range.
+      if (this.pairwiseTimedRange_) {
+        this.hasSeenTimerMarker_ = false;
+      }
     } else {
       this.hasSeenTimerMarker_ = true;
     }
   } else {
     if (this.hasSeenTimerMarker_) {
       this.logLinesSinceLastTimerMarker_.push(line);
     } else if (!line.startsWith("tick")) {
       this.processLog_([line]);
     }
   }
@@ skipping 90 matching lines @@
       continue;
     }
     try {
       var fields = this.csvParser_.parseLine(line);
       this.dispatchLogRow_(fields);
     } catch (e) {
       this.printError('line ' + (this.lineNum_ + 1) + ': ' + (e.message || e));
     }
   }
 };