WebKit/chromium/src/js/HeapProfilerPanel.js
changeset 0 4f2f89ce4247
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/WebKit/chromium/src/js/HeapProfilerPanel.js	Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,966 @@
+/*
+ * Copyright (C) 2010 Google Inc. 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 with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/**
+ * @fileoverview Heap profiler panel implementation.
+ */
+
+WebInspector.ProfilesPanel.prototype.addSnapshot = function(snapshot) {
+    snapshot.title = WebInspector.UIString("Snapshot %d", snapshot.number);
+    snapshot.typeId = WebInspector.HeapSnapshotProfileType.TypeId;
+
+    var snapshots = WebInspector.HeapSnapshotProfileType.snapshots;
+    snapshots.push(snapshot);
+
+    snapshot.listIndex = snapshots.length - 1;
+
+    if (WebInspector.CPUProfile)
+        this.addProfileHeader(WebInspector.HeapSnapshotProfileType.TypeId, snapshot);
+    else
+        this.addProfileHeader(snapshot);
+
+    this.dispatchEventToListeners("snapshot added");
+}
+
+
+WebInspector.HeapSnapshotView = function(parent, profile)
+{
+    WebInspector.View.call(this);
+
+    this.element.addStyleClass("heap-snapshot-view");
+
+    this.parent = parent;
+    this.parent.addEventListener("snapshot added", this._updateBaseOptions, this);
+
+    this.showCountAsPercent = false;
+    this.showSizeAsPercent = false;
+    this.showCountDeltaAsPercent = false;
+    this.showSizeDeltaAsPercent = false;
+
+    this.categories = {
+        code: new WebInspector.ResourceCategory("code", WebInspector.UIString("Code"), "rgb(255,121,0)"),
+        data: new WebInspector.ResourceCategory("data", WebInspector.UIString("Objects"), "rgb(47,102,236)")
+    };
+
+    var summaryContainer = document.createElement("div");
+    summaryContainer.id = "heap-snapshot-summary-container";
+
+    this.countsSummaryBar = new WebInspector.SummaryBar(this.categories);
+    this.countsSummaryBar.element.className = "heap-snapshot-summary";
+    this.countsSummaryBar.calculator = new WebInspector.HeapSummaryCountCalculator();
+    var countsLabel = document.createElement("div");
+    countsLabel.className = "heap-snapshot-summary-label";
+    countsLabel.textContent = WebInspector.UIString("Count");
+    this.countsSummaryBar.element.appendChild(countsLabel);
+    summaryContainer.appendChild(this.countsSummaryBar.element);
+
+    this.sizesSummaryBar = new WebInspector.SummaryBar(this.categories);
+    this.sizesSummaryBar.element.className = "heap-snapshot-summary";
+    this.sizesSummaryBar.calculator = new WebInspector.HeapSummarySizeCalculator();
+    var sizesLabel = document.createElement("label");
+    sizesLabel.className = "heap-snapshot-summary-label";
+    sizesLabel.textContent = WebInspector.UIString("Size");
+    this.sizesSummaryBar.element.appendChild(sizesLabel);
+    summaryContainer.appendChild(this.sizesSummaryBar.element);
+
+    this.element.appendChild(summaryContainer);
+
+    var columns = { "cons": { title: WebInspector.UIString("Constructor"), disclosure: true, sortable: true },
+                    "count": { title: WebInspector.UIString("Count"), width: "54px", sortable: true },
+                    "size": { title: WebInspector.UIString("Size"), width: "72px", sort: "descending", sortable: true },
+                    "countDelta": { title: WebInspector.UIString("\xb1 Count"), width: "72px", sortable: true },
+                    "sizeDelta": { title: WebInspector.UIString("\xb1 Size"), width: "72px", sortable: true } };
+
+    this.dataGrid = new WebInspector.DataGrid(columns);
+    this.dataGrid.addEventListener("sorting changed", this._sortData, this);
+    this.dataGrid.element.addEventListener("mousedown", this._mouseDownInDataGrid.bind(this), true);
+    this.element.appendChild(this.dataGrid.element);
+
+    this.profile = profile;
+
+    this.baseSelectElement = document.createElement("select");
+    this.baseSelectElement.className = "status-bar-item";
+    this.baseSelectElement.addEventListener("change", this._changeBase.bind(this), false);
+    this._updateBaseOptions();
+    if (this.profile.listIndex > 0)
+        this.baseSelectElement.selectedIndex = this.profile.listIndex - 1;
+    else
+        this.baseSelectElement.selectedIndex = this.profile.listIndex;
+    this._resetDataGridList();
+
+    this.percentButton = new WebInspector.StatusBarButton("", "percent-time-status-bar-item status-bar-item");
+    this.percentButton.addEventListener("click", this._percentClicked.bind(this), false);
+
+    this.refresh();
+
+    this._updatePercentButton();
+};
+
+WebInspector.HeapSnapshotView.prototype = {
+
+    get statusBarItems()
+    {
+        return [this.baseSelectElement, this.percentButton.element];
+    },
+
+    get profile()
+    {
+        return this._profile;
+    },
+
+    set profile(profile)
+    {
+        this._profile = profile;
+    },
+
+    show: function(parentElement)
+    {
+        WebInspector.View.prototype.show.call(this, parentElement);
+        this.dataGrid.updateWidths();
+    },
+
+    hide: function()
+    {
+        WebInspector.View.prototype.hide.call(this);
+        this._currentSearchResultIndex = -1;
+    },
+
+    resize: function()
+    {
+        if (this.dataGrid)
+            this.dataGrid.updateWidths();
+    },
+
+    refresh: function()
+    {
+        this.dataGrid.removeChildren();
+
+        var children = this.snapshotDataGridList.children;
+        var count = children.length;
+        for (var index = 0; index < count; ++index)
+            this.dataGrid.appendChild(children[index]);
+
+        this._updateSummaryGraph();
+    },
+
+    refreshShowAsPercents: function()
+    {
+        this._updatePercentButton();
+        this.refreshVisibleData();
+    },
+
+    _deleteSearchMatchedFlags: function(node)
+    {
+        delete node._searchMatchedConsColumn;
+        delete node._searchMatchedCountColumn;
+        delete node._searchMatchedSizeColumn;
+        delete node._searchMatchedCountDeltaColumn;
+        delete node._searchMatchedSizeDeltaColumn;
+    },
+
+    searchCanceled: function()
+    {
+        if (this._searchResults) {
+            for (var i = 0; i < this._searchResults.length; ++i) {
+                var profileNode = this._searchResults[i].profileNode;
+                this._deleteSearchMatchedFlags(profileNode);
+                profileNode.refresh();
+            }
+        }
+
+        delete this._searchFinishedCallback;
+        this._currentSearchResultIndex = -1;
+        this._searchResults = [];
+    },
+
+    performSearch: function(query, finishedCallback)
+    {
+        // Call searchCanceled since it will reset everything we need before doing a new search.
+        this.searchCanceled();
+
+        query = query.trim();
+
+        if (!query.length)
+            return;
+
+        this._searchFinishedCallback = finishedCallback;
+
+        var helper = WebInspector.HeapSnapshotView.SearchHelper;
+
+        var operationAndNumber = helper.parseOperationAndNumber(query);
+        var operation = operationAndNumber[0];
+        var queryNumber = operationAndNumber[1];
+
+        var percentUnits = helper.percents.test(query);
+        var megaBytesUnits = helper.megaBytes.test(query);
+        var kiloBytesUnits = helper.kiloBytes.test(query);
+        var bytesUnits = helper.bytes.test(query);
+
+        var queryNumberBytes = (megaBytesUnits ? (queryNumber * 1024 * 1024) : (kiloBytesUnits ? (queryNumber * 1024) : queryNumber));
+
+        function matchesQuery(heapSnapshotDataGridNode)
+        {
+            WebInspector.HeapSnapshotView.prototype._deleteSearchMatchedFlags(heapSnapshotDataGridNode);
+
+            if (percentUnits) {
+                heapSnapshotDataGridNode._searchMatchedCountColumn = operation(heapSnapshotDataGridNode.countPercent, queryNumber);
+                heapSnapshotDataGridNode._searchMatchedSizeColumn = operation(heapSnapshotDataGridNode.sizePercent, queryNumber);
+                heapSnapshotDataGridNode._searchMatchedCountDeltaColumn = operation(heapSnapshotDataGridNode.countDeltaPercent, queryNumber);
+                heapSnapshotDataGridNode._searchMatchedSizeDeltaColumn = operation(heapSnapshotDataGridNode.sizeDeltaPercent, queryNumber);
+            } else if (megaBytesUnits || kiloBytesUnits || bytesUnits) {
+                heapSnapshotDataGridNode._searchMatchedSizeColumn = operation(heapSnapshotDataGridNode.size, queryNumberBytes);
+                heapSnapshotDataGridNode._searchMatchedSizeDeltaColumn = operation(heapSnapshotDataGridNode.sizeDelta, queryNumberBytes);
+            } else {
+                heapSnapshotDataGridNode._searchMatchedCountColumn = operation(heapSnapshotDataGridNode.count, queryNumber);
+                heapSnapshotDataGridNode._searchMatchedCountDeltaColumn = operation(heapSnapshotDataGridNode.countDelta, queryNumber);
+            }
+
+            if (heapSnapshotDataGridNode.constructorName.hasSubstring(query, true))
+                heapSnapshotDataGridNode._searchMatchedConsColumn = true;
+
+            if (heapSnapshotDataGridNode._searchMatchedConsColumn ||
+                heapSnapshotDataGridNode._searchMatchedCountColumn ||
+                heapSnapshotDataGridNode._searchMatchedSizeColumn ||
+                heapSnapshotDataGridNode._searchMatchedCountDeltaColumn ||
+                heapSnapshotDataGridNode._searchMatchedSizeDeltaColumn) {
+                heapSnapshotDataGridNode.refresh();
+                return true;
+            }
+
+            return false;
+        }
+
+        var current = this.snapshotDataGridList.children[0];
+        var depth = 0;
+        var info = {};
+
+        // The second and subsequent levels of heap snapshot nodes represent retainers,
+        // so recursive expansion will be infinite, since a graph is being traversed.
+        // So default to a recursion cap of 2 levels.
+        var maxDepth = 2;
+
+        while (current) {
+            if (matchesQuery(current))
+                this._searchResults.push({ profileNode: current });
+            current = current.traverseNextNode(false, null, (depth >= maxDepth), info);
+            depth += info.depthChange;
+        }
+
+        finishedCallback(this, this._searchResults.length);
+    },
+
+    jumpToFirstSearchResult: WebInspector.CPUProfileView.prototype.jumpToFirstSearchResult,
+    jumpToLastSearchResult: WebInspector.CPUProfileView.prototype.jumpToLastSearchResult,
+    jumpToNextSearchResult: WebInspector.CPUProfileView.prototype.jumpToNextSearchResult,
+    jumpToPreviousSearchResult: WebInspector.CPUProfileView.prototype.jumpToPreviousSearchResult,
+    showingFirstSearchResult: WebInspector.CPUProfileView.prototype.showingFirstSearchResult,
+    showingLastSearchResult: WebInspector.CPUProfileView.prototype.showingLastSearchResult,
+    _jumpToSearchResult: WebInspector.CPUProfileView.prototype._jumpToSearchResult,
+
+    refreshVisibleData: function()
+    {
+        var child = this.dataGrid.children[0];
+        while (child) {
+            child.refresh();
+            child = child.traverseNextNode(false, null, true);
+        }
+        this._updateSummaryGraph();
+    },
+
+    _changeBase: function() {
+        if (this.baseSnapshot === WebInspector.HeapSnapshotProfileType.snapshots[this.baseSelectElement.selectedIndex])
+            return;
+
+        this._resetDataGridList();
+        this.refresh();
+
+        if (!this.currentQuery || !this._searchFinishedCallback || !this._searchResults)
+            return;
+
+        // The current search needs to be performed again. First negate out previous match
+        // count by calling the search finished callback with a negative number of matches.
+        // Then perform the search again with the same query and callback.
+        this._searchFinishedCallback(this, -this._searchResults.length);
+        this.performSearch(this.currentQuery, this._searchFinishedCallback);
+    },
+
+    _createSnapshotDataGridList: function()
+    {
+        if (this._snapshotDataGridList)
+          delete this._snapshotDataGridList;
+
+        this._snapshotDataGridList = new WebInspector.HeapSnapshotDataGridList(this, this.baseSnapshot.entries, this.profile.entries);
+        return this._snapshotDataGridList;
+    },
+
+    _mouseDownInDataGrid: function(event)
+    {
+        if (event.detail < 2)
+            return;
+
+        var cell = event.target.enclosingNodeOrSelfWithNodeName("td");
+        if (!cell || (!cell.hasStyleClass("count-column") && !cell.hasStyleClass("size-column") && !cell.hasStyleClass("countDelta-column") && !cell.hasStyleClass("sizeDelta-column")))
+            return;
+
+        if (cell.hasStyleClass("count-column"))
+            this.showCountAsPercent = !this.showCountAsPercent;
+        else if (cell.hasStyleClass("size-column"))
+            this.showSizeAsPercent = !this.showSizeAsPercent;
+        else if (cell.hasStyleClass("countDelta-column"))
+            this.showCountDeltaAsPercent = !this.showCountDeltaAsPercent;
+        else if (cell.hasStyleClass("sizeDelta-column"))
+            this.showSizeDeltaAsPercent = !this.showSizeDeltaAsPercent;
+
+        this.refreshShowAsPercents();
+
+        event.preventDefault();
+        event.stopPropagation();
+    },
+
+    get _isShowingAsPercent()
+    {
+        return this.showCountAsPercent && this.showSizeAsPercent && this.showCountDeltaAsPercent && this.showSizeDeltaAsPercent;
+    },
+
+    _percentClicked: function(event)
+    {
+        var currentState = this._isShowingAsPercent;
+        this.showCountAsPercent = !currentState;
+        this.showSizeAsPercent = !currentState;
+        this.showCountDeltaAsPercent = !currentState;
+        this.showSizeDeltaAsPercent = !currentState;
+        this.refreshShowAsPercents();
+    },
+
+    _resetDataGridList: function()
+    {
+        this.baseSnapshot = WebInspector.HeapSnapshotProfileType.snapshots[this.baseSelectElement.selectedIndex];
+        var lastComparator = WebInspector.HeapSnapshotDataGridList.propertyComparator("size", false);
+        if (this.snapshotDataGridList)
+            lastComparator = this.snapshotDataGridList.lastComparator;
+        this.snapshotDataGridList = this._createSnapshotDataGridList();
+        this.snapshotDataGridList.sort(lastComparator, true);
+    },
+
+    _sortData: function()
+    {
+        var sortAscending = this.dataGrid.sortOrder === "ascending";
+        var sortColumnIdentifier = this.dataGrid.sortColumnIdentifier;
+        var sortProperty = {
+                "cons": ["constructorName", null],
+                "count": ["count", null],
+                "size": ["size", "count"],
+                "countDelta": this.showCountDeltaAsPercent ? ["countDeltaPercent", null] : ["countDelta", null],
+                "sizeDelta": this.showSizeDeltaAsPercent ? ["sizeDeltaPercent", "countDeltaPercent"] : ["sizeDelta", "sizeDeltaPercent"]
+        }[sortColumnIdentifier];
+
+        this.snapshotDataGridList.sort(WebInspector.HeapSnapshotDataGridList.propertyComparator(sortProperty[0], sortProperty[1], sortAscending));
+
+        this.refresh();
+    },
+
+    _updateBaseOptions: function()
+    {
+        var list = WebInspector.HeapSnapshotProfileType.snapshots;
+        // We're assuming that snapshots can only be added.
+        if (this.baseSelectElement.length === list.length)
+            return;
+
+        for (var i = this.baseSelectElement.length, n = list.length; i < n; ++i) {
+            var baseOption = document.createElement("option");
+            baseOption.label = WebInspector.UIString("Compared to %s", list[i].title);
+            this.baseSelectElement.appendChild(baseOption);
+        }
+    },
+
+    _updatePercentButton: function()
+    {
+        if (this._isShowingAsPercent) {
+            this.percentButton.title = WebInspector.UIString("Show absolute counts and sizes.");
+            this.percentButton.toggled = true;
+        } else {
+            this.percentButton.title = WebInspector.UIString("Show counts and sizes as percentages.");
+            this.percentButton.toggled = false;
+        }
+    },
+
+    _updateSummaryGraph: function()
+    {
+        this.countsSummaryBar.calculator.showAsPercent = this._isShowingAsPercent;
+        this.countsSummaryBar.update(this.profile.lowlevels);
+
+        this.sizesSummaryBar.calculator.showAsPercent = this._isShowingAsPercent;
+        this.sizesSummaryBar.update(this.profile.lowlevels);
+    }
+};
+
+WebInspector.HeapSnapshotView.prototype.__proto__ = WebInspector.View.prototype;
+
+WebInspector.HeapSnapshotView.SearchHelper = {
+    // In comparators, we assume that a value from a node is passed as the first parameter.
+    operations: { LESS: function (a, b) { return a !== null && a < b; },
+                  LESS_OR_EQUAL: function (a, b) { return a !== null && a <= b; },
+                  EQUAL: function (a, b) { return a !== null && a === b; },
+                  GREATER_OR_EQUAL: function (a, b) { return a !== null && a >= b; },
+                  GREATER: function (a, b) { return a !== null && a > b; } },
+
+    operationParsers: { LESS: /^<(\d+)/,
+                        LESS_OR_EQUAL: /^<=(\d+)/,
+                        GREATER_OR_EQUAL: /^>=(\d+)/,
+                        GREATER: /^>(\d+)/ },
+
+    parseOperationAndNumber: function(query)
+    {
+        var operations = WebInspector.HeapSnapshotView.SearchHelper.operations;
+        var parsers = WebInspector.HeapSnapshotView.SearchHelper.operationParsers;
+        for (var operation in parsers) {
+            var match = query.match(parsers[operation]);
+            if (match !== null)
+                return [operations[operation], parseFloat(match[1])];
+        }
+        return [operations.EQUAL, parseFloat(query)];
+    },
+
+    percents: /%$/,
+
+    megaBytes: /MB$/i,
+
+    kiloBytes: /KB$/i,
+
+    bytes: /B$/i
+}
+
+WebInspector.HeapSummaryCalculator = function(lowLevelField)
+{
+    this.total = 1;
+    this.lowLevelField = lowLevelField;
+}
+
+WebInspector.HeapSummaryCalculator.prototype = {
+    computeSummaryValues: function(lowLevels)
+    {
+        var highLevels = {data: 0, code: 0};
+        this.total = 0;
+        for (var item in lowLevels) {
+            var highItem = this._highFromLow(item);
+            if (highItem) {
+                var value = lowLevels[item][this.lowLevelField];
+                highLevels[highItem] += value;
+                this.total += value;
+            }
+        }
+        var result = {categoryValues: highLevels};
+        if (!this.showAsPercent)
+            result.total = this.total;
+        return result;
+    },
+
+    formatValue: function(value)
+    {
+        if (this.showAsPercent)
+            return WebInspector.UIString("%.2f%%", value / this.total * 100.0);
+        else
+            return this._valueToString(value);
+    },
+
+    get showAsPercent()
+    {
+        return this._showAsPercent;
+    },
+
+    set showAsPercent(x)
+    {
+        this._showAsPercent = x;
+    }
+}
+
+WebInspector.HeapSummaryCountCalculator = function()
+{
+    WebInspector.HeapSummaryCalculator.call(this, "count");
+}
+
+WebInspector.HeapSummaryCountCalculator.prototype = {
+    _highFromLow: function(type) {
+        if (type === "CODE_TYPE" || type === "SHARED_FUNCTION_INFO_TYPE" || type === "SCRIPT_TYPE") return "code";
+        if (type === "STRING_TYPE" || type === "HEAP_NUMBER_TYPE" || type.match(/^JS_/)) return "data";
+        return null;
+    },
+
+    _valueToString: function(value) {
+        return value.toString();
+    }
+}
+
+WebInspector.HeapSummaryCountCalculator.prototype.__proto__ = WebInspector.HeapSummaryCalculator.prototype;
+
+WebInspector.HeapSummarySizeCalculator = function()
+{
+    WebInspector.HeapSummaryCalculator.call(this, "size");
+}
+
+WebInspector.HeapSummarySizeCalculator.prototype = {
+    _highFromLow: function(type) {
+        if (type === "CODE_TYPE" || type === "SHARED_FUNCTION_INFO_TYPE" || type === "SCRIPT_TYPE") return "code";
+        if (type === "STRING_TYPE" || type === "HEAP_NUMBER_TYPE" || type.match(/^JS_/) || type.match(/_ARRAY_TYPE$/)) return "data";
+        return null;
+    },
+
+    _valueToString: Number.bytesToString
+}
+
+WebInspector.HeapSummarySizeCalculator.prototype.__proto__ = WebInspector.HeapSummaryCalculator.prototype;
+
+WebInspector.HeapSnapshotSidebarTreeElement = function(snapshot)
+{
+    this.profile = snapshot;
+
+    WebInspector.SidebarTreeElement.call(this, "heap-snapshot-sidebar-tree-item", "", "", snapshot, false);
+
+    this.refreshTitles();
+};
+
+WebInspector.HeapSnapshotSidebarTreeElement.prototype = {
+    get mainTitle()
+    {
+        if (this._mainTitle)
+            return this._mainTitle;
+        return this.profile.title;
+    },
+
+    set mainTitle(x)
+    {
+        this._mainTitle = x;
+        this.refreshTitles();
+    }
+};
+
+WebInspector.HeapSnapshotSidebarTreeElement.prototype.__proto__ = WebInspector.ProfileSidebarTreeElement.prototype;
+
+WebInspector.HeapSnapshotDataGridNodeWithRetainers = function(owningTree)
+{
+    this.tree = owningTree;
+
+    WebInspector.DataGridNode.call(this, null, this._hasRetainers);
+
+    this.addEventListener("populate", this._populate, this);
+};
+
+WebInspector.HeapSnapshotDataGridNodeWithRetainers.prototype = {
+    isEmptySet: function(set)
+    {
+        for (var x in set)
+            return false;
+        return true;
+    },
+
+    get _hasRetainers()
+    {
+        return !this.isEmptySet(this.retainers);
+    },
+
+    get _parent()
+    {
+        // For top-level nodes, return owning tree as a parent, not data grid.
+        return this.parent !== this.dataGrid ? this.parent : this.tree;
+    },
+
+    _populate: function(event)
+    {
+        var self = this;
+        this.produceDiff(this.baseRetainers, this.retainers, function(baseItem, snapshotItem) {
+            self.appendChild(new WebInspector.HeapSnapshotDataGridRetainerNode(self.snapshotView, baseItem, snapshotItem, self.tree));
+        });
+
+        if (this._parent) {
+            var currentComparator = this._parent.lastComparator;
+            if (currentComparator)
+                this.sort(currentComparator, true);
+        }
+
+        this.removeEventListener("populate", this._populate, this);
+    },
+
+    produceDiff: function(baseEntries, currentEntries, callback)
+    {
+        for (var item in currentEntries)
+            callback(baseEntries[item], currentEntries[item]);
+
+        for (item in baseEntries) {
+            if (!(item in currentEntries))
+                callback(baseEntries[item], null);
+        }
+    },
+
+    sort: function(comparator, force) {
+        if (!force && this.lastComparator === comparator)
+            return;
+
+        this.children.sort(comparator);
+        var childCount = this.children.length;
+        for (var childIndex = 0; childIndex < childCount; ++childIndex)
+            this.children[childIndex]._recalculateSiblings(childIndex);
+        for (var i = 0; i < this.children.length; ++i) {
+            var child = this.children[i];
+            if (!force && (!child.expanded || child.lastComparator === comparator))
+                continue;
+            child.sort(comparator, force);
+        }
+        this.lastComparator = comparator;
+    },
+
+    signForDelta: function(delta) {
+        if (delta === 0)
+            return "";
+        if (delta > 0)
+            return "+";
+        else
+            // Math minus sign, same width as plus.
+            return "\u2212";
+    },
+
+    showDeltaAsPercent: function(value) {
+        if (value === Number.POSITIVE_INFINITY)
+            return WebInspector.UIString("new");
+        else if (value === Number.NEGATIVE_INFINITY)
+            return WebInspector.UIString("deleted");
+        if (value > 1000.0)
+            return WebInspector.UIString("%s >1000%%", this.signForDelta(value));
+        return WebInspector.UIString("%s%.2f%%", this.signForDelta(value), Math.abs(value));
+    },
+
+    getTotalCount: function() {
+        if (!this._count) {
+            this._count = 0;
+            for (var i = 0, n = this.children.length; i < n; ++i)
+                this._count += this.children[i].count;
+        }
+        return this._count;
+    },
+
+    getTotalSize: function() {
+        if (!this._size) {
+            this._size = 0;
+            for (var i = 0, n = this.children.length; i < n; ++i)
+                this._size += this.children[i].size;
+        }
+        return this._size;
+    },
+
+    get countPercent()
+    {
+        return this.count / this._parent.getTotalCount() * 100.0;
+    },
+
+    get sizePercent()
+    {
+        return this.size / this._parent.getTotalSize() * 100.0;
+    },
+
+    get countDeltaPercent()
+    {
+        if (this.baseCount > 0) {
+            if (this.count > 0)
+                return this.countDelta / this.baseCount * 100.0;
+            else
+                return Number.NEGATIVE_INFINITY;
+        } else
+            return Number.POSITIVE_INFINITY;
+    },
+
+    get sizeDeltaPercent()
+    {
+        if (this.baseSize > 0) {
+            if (this.size > 0)
+                return this.sizeDelta / this.baseSize * 100.0;
+            else
+                return Number.NEGATIVE_INFINITY;
+        } else
+            return Number.POSITIVE_INFINITY;
+    },
+
+    get data()
+    {
+        var data = {};
+
+        data["cons"] = this.constructorName;
+
+        if (this.snapshotView.showCountAsPercent)
+            data["count"] = WebInspector.UIString("%.2f%%", this.countPercent);
+        else
+            data["count"] = this.count;
+
+        if (this.size !== null) {
+            if (this.snapshotView.showSizeAsPercent)
+                data["size"] = WebInspector.UIString("%.2f%%", this.sizePercent);
+            else
+                data["size"] = Number.bytesToString(this.size);
+        } else
+            data["size"] = "";
+
+        if (this.snapshotView.showCountDeltaAsPercent)
+            data["countDelta"] = this.showDeltaAsPercent(this.countDeltaPercent);
+        else
+            data["countDelta"] = WebInspector.UIString("%s%d", this.signForDelta(this.countDelta), Math.abs(this.countDelta));
+
+        if (this.sizeDelta !== null) {
+            if (this.snapshotView.showSizeDeltaAsPercent)
+                data["sizeDelta"] = this.showDeltaAsPercent(this.sizeDeltaPercent);
+            else
+                data["sizeDelta"] = WebInspector.UIString("%s%s", this.signForDelta(this.sizeDelta), Number.bytesToString(Math.abs(this.sizeDelta)));
+        } else
+            data["sizeDelta"] = "";
+
+        return data;
+    },
+
+    createCell: function(columnIdentifier)
+    {
+        var cell = WebInspector.DataGridNode.prototype.createCell.call(this, columnIdentifier);
+
+        if ((columnIdentifier === "cons" && this._searchMatchedConsColumn) ||
+            (columnIdentifier === "count" && this._searchMatchedCountColumn) ||
+            (columnIdentifier === "size" && this._searchMatchedSizeColumn) ||
+            (columnIdentifier === "countDelta" && this._searchMatchedCountDeltaColumn) ||
+            (columnIdentifier === "sizeDelta" && this._searchMatchedSizeDeltaColumn))
+            cell.addStyleClass("highlight");
+
+        return cell;
+    }
+};
+
+WebInspector.HeapSnapshotDataGridNodeWithRetainers.prototype.__proto__ = WebInspector.DataGridNode.prototype;
+
+WebInspector.HeapSnapshotDataGridNode = function(snapshotView, baseEntry, snapshotEntry, owningTree)
+{
+    this.snapshotView = snapshotView;
+
+    if (!snapshotEntry)
+        snapshotEntry = { cons: baseEntry.cons, count: 0, size: 0, retainers: {} };
+    this.constructorName = snapshotEntry.cons;
+    this.count = snapshotEntry.count;
+    this.size = snapshotEntry.size;
+    this.retainers = snapshotEntry.retainers;
+
+    if (!baseEntry)
+        baseEntry = { count: 0, size: 0, retainers: {} };
+    this.baseCount = baseEntry.count;
+    this.countDelta = this.count - this.baseCount;
+    this.baseSize = baseEntry.size;
+    this.sizeDelta = this.size - this.baseSize;
+    this.baseRetainers = baseEntry.retainers;
+
+    WebInspector.HeapSnapshotDataGridNodeWithRetainers.call(this, owningTree);
+};
+
+WebInspector.HeapSnapshotDataGridNode.prototype.__proto__ = WebInspector.HeapSnapshotDataGridNodeWithRetainers.prototype;
+
+WebInspector.HeapSnapshotDataGridList = function(snapshotView, baseEntries, snapshotEntries)
+{
+    this.tree = this;
+    this.snapshotView = snapshotView;
+    this.children = [];
+    this.lastComparator = null;
+    this.populateChildren(baseEntries, snapshotEntries);
+};
+
+WebInspector.HeapSnapshotDataGridList.prototype = {
+    appendChild: function(child)
+    {
+        this.insertChild(child, this.children.length);
+    },
+
+    insertChild: function(child, index)
+    {
+        this.children.splice(index, 0, child);
+    },
+
+    removeChildren: function()
+    {
+        this.children = [];
+    },
+
+    populateChildren: function(baseEntries, snapshotEntries)
+    {
+        var self = this;
+        this.produceDiff(baseEntries, snapshotEntries, function(baseItem, snapshotItem) {
+            self.appendChild(new WebInspector.HeapSnapshotDataGridNode(self.snapshotView, baseItem, snapshotItem, self));
+        });
+    },
+
+    produceDiff: WebInspector.HeapSnapshotDataGridNodeWithRetainers.prototype.produceDiff,
+    sort: WebInspector.HeapSnapshotDataGridNodeWithRetainers.prototype.sort,
+    getTotalCount: WebInspector.HeapSnapshotDataGridNodeWithRetainers.prototype.getTotalCount,
+    getTotalSize: WebInspector.HeapSnapshotDataGridNodeWithRetainers.prototype.getTotalSize
+};
+
+WebInspector.HeapSnapshotDataGridList.propertyComparators = [{}, {}];
+
+WebInspector.HeapSnapshotDataGridList.propertyComparator = function(property, property2, isAscending)
+{
+    var propertyHash = property + "#" + property2;
+    var comparator = this.propertyComparators[(isAscending ? 1 : 0)][propertyHash];
+    if (!comparator) {
+        comparator = function(lhs, rhs) {
+            var l = lhs[property], r = rhs[property];
+            if ((l === null || r === null) && property2 !== null)
+                l = lhs[property2], r = rhs[property2];
+            var result = l < r ? -1 : (l > r ? 1 : 0);
+            return isAscending ? result : -result;
+        };
+        this.propertyComparators[(isAscending ? 1 : 0)][propertyHash] = comparator;
+    }
+    return comparator;
+};
+
+WebInspector.HeapSnapshotDataGridRetainerNode = function(snapshotView, baseEntry, snapshotEntry, owningTree)
+{
+    this.snapshotView = snapshotView;
+
+    if (!snapshotEntry)
+        snapshotEntry = { cons: baseEntry.cons, count: 0, clusters: {} };
+    this.constructorName = snapshotEntry.cons;
+    this.count = snapshotEntry.count;
+    this.retainers = this._calculateRetainers(this.snapshotView.profile, snapshotEntry.clusters);
+
+    if (!baseEntry)
+        baseEntry = { count: 0, clusters: {} };
+    this.baseCount = baseEntry.count;
+    this.countDelta = this.count - this.baseCount;
+    this.baseRetainers = this._calculateRetainers(this.snapshotView.baseSnapshot, baseEntry.clusters);
+
+    this.size = null;
+    this.sizeDelta = null;
+
+    WebInspector.HeapSnapshotDataGridNodeWithRetainers.call(this, owningTree);
+}
+
+WebInspector.HeapSnapshotDataGridRetainerNode.prototype = {
+    get sizePercent()
+    {
+        return null;
+    },
+
+    get sizeDeltaPercent()
+    {
+        return null;
+    },
+
+    _calculateRetainers: function(snapshot, clusters) {
+        var retainers = {};
+        if (this.isEmptySet(clusters)) {
+            if (this.constructorName in snapshot.entries)
+                return snapshot.entries[this.constructorName].retainers;
+        } else {
+            // In case when an entry is retained by clusters, we need to gather up the list
+            // of retainers by merging retainers of every cluster.
+            // E.g. having such a tree:
+            //   A
+            //     Object:1  10
+            //       X       3
+            //       Y       4
+            //     Object:2  5
+            //       X       6
+            //
+            // will result in a following retainers list: X 9, Y 4.
+            for (var clusterName in clusters) {
+                if (clusterName in snapshot.clusters) {
+                    var clusterRetainers = snapshot.clusters[clusterName].retainers;
+                    for (var clusterRetainer in clusterRetainers) {
+                        var clusterRetainerEntry = clusterRetainers[clusterRetainer];
+                        if (!(clusterRetainer in retainers))
+                            retainers[clusterRetainer] = { cons: clusterRetainerEntry.cons, count: 0, clusters: {} };
+                        retainers[clusterRetainer].count += clusterRetainerEntry.count;
+                        for (var clusterRetainerCluster in clusterRetainerEntry.clusters)
+                            retainers[clusterRetainer].clusters[clusterRetainerCluster] = true;
+                    }
+                }
+            }
+        }
+        return retainers;
+    }
+};
+
+WebInspector.HeapSnapshotDataGridRetainerNode.prototype.__proto__ = WebInspector.HeapSnapshotDataGridNodeWithRetainers.prototype;
+
+
+WebInspector.HeapSnapshotProfileType = function()
+{
+    WebInspector.ProfileType.call(this, WebInspector.HeapSnapshotProfileType.TypeId, WebInspector.UIString("HEAP SNAPSHOTS"));
+}
+
+WebInspector.HeapSnapshotProfileType.TypeId = "HEAP";
+
+WebInspector.HeapSnapshotProfileType.snapshots = [];
+
+WebInspector.HeapSnapshotProfileType.prototype = {
+    get buttonTooltip()
+    {
+        return WebInspector.UIString("Take heap snapshot.");
+    },
+
+    get buttonStyle()
+    {
+        return "heap-snapshot-status-bar-item status-bar-item";
+    },
+
+    buttonClicked: function()
+    {
+        devtools.tools.getProfilerAgent().startProfiling(devtools.ProfilerAgent.ProfilerModules.PROFILER_MODULE_HEAP_SNAPSHOT);
+    },
+
+    get welcomeMessage()
+    {
+        return WebInspector.UIString("Get a heap snapshot by pressing the %s button on the status bar.");
+    },
+
+    createSidebarTreeElementForProfile: function(profile)
+    {
+        var element = new WebInspector.HeapSnapshotSidebarTreeElement(profile);
+        element.small = false;
+        return element;
+    },
+
+    createView: function(profile)
+    {
+        return new WebInspector.HeapSnapshotView(WebInspector.panels.profiles, profile);
+    }
+}
+
+WebInspector.HeapSnapshotProfileType.prototype.__proto__ = WebInspector.ProfileType.prototype;
+
+
+(function() {
+    var originalCreatePanels = WebInspector._createPanels;
+    WebInspector._createPanels = function() {
+        originalCreatePanels.apply(this, arguments);
+        if (WebInspector.panels.profiles)
+            WebInspector.panels.profiles.registerProfileType(new WebInspector.HeapSnapshotProfileType());
+    }
+})();