Don't keep data about JS code that is never executed, optimize static symbols loading

tools/codemap.js

 // Copyright 2009 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 25 matching lines @@
  *
  * @constructor
  */
 devtools.profiler.CodeMap = function() {
   /**
    * Dynamic code entries. Used for JIT compiled code.
    */
   this.dynamics_ = new goog.structs.SplayTree();
 
   /**
-   * Deleted code entries. Used for code collected by the GC.
+   * Name generator for entries having duplicate names.
    */
-  this.deleted_ = [];
-
   this.dynamicsNameGen_ = new devtools.profiler.CodeMap.NameGenerator();
 
   /**
    * Static code entries. Used for libraries code.
    */
   this.statics_ = new goog.structs.SplayTree();
 
   /**
    * Map of memory pages occupied with static code.
    */
@@ skipping 14 matching lines @@
     1 << devtools.profiler.CodeMap.PAGE_ALIGNMENT;
 
 
 /**
  * Adds a dynamic (i.e. moveable and discardable) code entry.
  *
  * @param {number} start The starting address.
  * @param {devtools.profiler.CodeMap.CodeEntry} codeEntry Code entry object.
  */
 devtools.profiler.CodeMap.prototype.addCode = function(start, codeEntry) {
-  var entryName = this.dynamicsNameGen_.getName(codeEntry.name);
-  codeEntry.name = entryName;
   this.dynamics_.insert(start, codeEntry);
 };
 
 
 /**
  * Moves a dynamic code entry. Throws an exception if there is no dynamic
  * code entry with the specified starting address.
  *
  * @param {number} from The starting address of the entry being moved.
  * @param {number} to The destination address.
  */
 devtools.profiler.CodeMap.prototype.moveCode = function(from, to) {
   var removedNode = this.dynamics_.remove(from);
   this.dynamics_.insert(to, removedNode.value);
 };
 
 
 /**
  * Discards a dynamic code entry. Throws an exception if there is no dynamic
- * code entry with the specified starting address. The entry will still be
- * returned from the 'getAllDynamicEntries' method.
+ * code entry with the specified starting address.
  *
  * @param {number} start The starting address of the entry being deleted.
  */
 devtools.profiler.CodeMap.prototype.deleteCode = function(start) {
   var removedNode = this.dynamics_.remove(start);
-  this.deleted_.push(removedNode.value);
 };
 
 
 /**
  * Adds a static code entry.
  *
  * @param {number} start The starting address.
  * @param {devtools.profiler.CodeMap.CodeEntry} codeEntry Code entry object.
  */
 devtools.profiler.CodeMap.prototype.addStaticCode = function(
@@ skipping 38 matching lines @@
  * @param {number} addr Address.
  */
 devtools.profiler.CodeMap.prototype.findEntry = function(addr) {
   var pageAddr = addr >> devtools.profiler.CodeMap.PAGE_ALIGNMENT;
   if (pageAddr in this.pages_) {
     return this.findInTree_(this.statics_, addr);
   }
   var min = this.dynamics_.findMin();
   var max = this.dynamics_.findMax();
   if (max != null && addr < (max.key + max.value.size) && addr >= min.key) {
-    return this.findInTree_(this.dynamics_, addr);
+    var dynaEntry = this.findInTree_(this.dynamics_, addr);
+    if (dynaEntry == null) return null;
+    // Dedupe entry name.
+    if (!dynaEntry.nameUpdated_) {

[Søren Thygesen Gjesse, 2009/05/08 09:54:48]

Is it alright to access 'private' members using other than this? As CodeEntry in
inside CodeMap it is probably fine.

[Mikhail Naganov, 2009/05/08 11:25:40]

I think so.

+      dynaEntry.name = this.dynamicsNameGen_.getName(dynaEntry.name);
+      dynaEntry.nameUpdated_ = true;
+    }
+    return dynaEntry;
   }
   return null;
 };
 
 
 /**
  * Returns an array of all dynamic code entries, including deleted ones.
  */
 devtools.profiler.CodeMap.prototype.getAllDynamicEntries = function() {
-  var dynamicEntries = this.dynamics_.exportValues();
-  return dynamicEntries.concat(this.deleted_);
+  return this.dynamics_.exportValues();
 };
 
 
 /**
  * Returns an array of all static code entries.
  */
 devtools.profiler.CodeMap.prototype.getAllStaticEntries = function() {
   return this.statics_.exportValues();
 };
 
 
 /**
  * Creates a code entry object.
  *
  * @param {number} size Code entry size in bytes.
  * @param {string} opt_name Code entry name.
  * @constructor
  */
 devtools.profiler.CodeMap.CodeEntry = function(size, opt_name) {
   this.size = size;
   this.name = opt_name || '';
+  this.nameUpdated_ = false;
 };
 
 
 devtools.profiler.CodeMap.CodeEntry.prototype.getName = function() {
   return this.name;
 };
 
 
 devtools.profiler.CodeMap.CodeEntry.prototype.toString = function() {
   return this.name + ': ' + this.size.toString(16);
 };
 
 
 devtools.profiler.CodeMap.NameGenerator = function() {
   this.knownNames_ = [];
 };
 
 
 devtools.profiler.CodeMap.NameGenerator.prototype.getName = function(name) {
   if (!(name in this.knownNames_)) {
     this.knownNames_[name] = 0;
     return name;
   }
   var count = ++this.knownNames_[name];
   return name + ' {' + count + '}';
 };