Remove obsolete v8_benchmark. It was replaced with Octane on the perf bots.

chrome/test/data/v8_benchmark/splay.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
-//       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.
-
-// This benchmark is based on a JavaScript log processing module used
-// by the V8 profiler to generate execution time profiles for runs of
-// JavaScript applications, and it effectively measures how fast the
-// JavaScript engine is at allocating nodes and reclaiming the memory
-// used for old nodes. Because of the way splay trees work, the engine
-// also has to deal with a lot of changes to the large tree object
-// graph.
-
-var Splay = new BenchmarkSuite('Splay', 81491, [
-  new Benchmark("Splay", SplayRun, SplaySetup, SplayTearDown)
-]);
-
-
-// Configuration.
-var kSplayTreeSize = 8000;
-var kSplayTreeModifications = 80;
-var kSplayTreePayloadDepth = 5;
-
-var splayTree = null;
-
-
-function GeneratePayloadTree(depth, tag) {
-  if (depth == 0) {
-    return {
-      array  : [ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 ],
-      string : 'String for key ' + tag + ' in leaf node'
-    };
-  } else {
-    return {
-      left:  GeneratePayloadTree(depth - 1, tag),
-      right: GeneratePayloadTree(depth - 1, tag)
-    };
-  }
-}
-
-
-function GenerateKey() {
-  // The benchmark framework guarantees that Math.random is
-  // deterministic; see base.js.
-  return Math.random();
-}
-
-
-function InsertNewNode() {
-  // Insert new node with a unique key.
-  var key;
-  do {
-    key = GenerateKey();
-  } while (splayTree.find(key) != null);
-  var payload = GeneratePayloadTree(kSplayTreePayloadDepth, String(key));
-  splayTree.insert(key, payload);
-  return key;
-}
-
-
-
-function SplaySetup() {
-  splayTree = new SplayTree();
-  for (var i = 0; i < kSplayTreeSize; i++) InsertNewNode();
-}
-
-
-function SplayTearDown() {
-  // Allow the garbage collector to reclaim the memory
-  // used by the splay tree no matter how we exit the
-  // tear down function.
-  var keys = splayTree.exportKeys();
-  splayTree = null;
-
-  // Verify that the splay tree has the right size.
-  var length = keys.length;
-  if (length != kSplayTreeSize) {
-    throw new Error("Splay tree has wrong size");
-  }
-
-  // Verify that the splay tree has sorted, unique keys.
-  for (var i = 0; i < length - 1; i++) {
-    if (keys[i] >= keys[i + 1]) {
-      throw new Error("Splay tree not sorted");
-    }
-  }
-}
-
-
-function SplayRun() {
-  // Replace a few nodes in the splay tree.
-  for (var i = 0; i < kSplayTreeModifications; i++) {
-    var key = InsertNewNode();
-    var greatest = splayTree.findGreatestLessThan(key);
-    if (greatest == null) splayTree.remove(key);
-    else splayTree.remove(greatest.key);
-  }
-}
-
-
-/**
- * Constructs a Splay tree.  A splay tree is a self-balancing binary
- * search tree with the additional property that recently accessed
- * elements are quick to access again. It performs basic operations
- * such as insertion, look-up and removal in O(log(n)) amortized time.
- *
- * @constructor
- */
-function SplayTree() {
-};
-
-
-/**
- * Pointer to the root node of the tree.
- *
- * @type {SplayTree.Node}
- * @private
- */
-SplayTree.prototype.root_ = null;
-
-
-/**
- * @return {boolean} Whether the tree is empty.
- */
-SplayTree.prototype.isEmpty = function() {
-  return !this.root_;
-};
-
-
-/**
- * Inserts a node into the tree with the specified key and value if
- * the tree does not already contain a node with the specified key. If
- * the value is inserted, it becomes the root of the tree.
- *
- * @param {number} key Key to insert into the tree.
- * @param {*} value Value to insert into the tree.
- */
-SplayTree.prototype.insert = function(key, value) {
-  if (this.isEmpty()) {
-    this.root_ = new SplayTree.Node(key, value);
-    return;
-  }
-  // Splay on the key to move the last node on the search path for
-  // the key to the root of the tree.
-  this.splay_(key);
-  if (this.root_.key == key) {
-    return;
-  }
-  var node = new SplayTree.Node(key, value);
-  if (key > this.root_.key) {
-    node.left = this.root_;
-    node.right = this.root_.right;
-    this.root_.right = null;
-  } else {
-    node.right = this.root_;
-    node.left = this.root_.left;
-    this.root_.left = null;
-  }
-  this.root_ = node;
-};
-
-
-/**
- * Removes a node with the specified key from the tree if the tree
- * contains a node with this key. The removed node is returned. If the
- * key is not found, an exception is thrown.
- *
- * @param {number} key Key to find and remove from the tree.
- * @return {SplayTree.Node} The removed node.
- */
-SplayTree.prototype.remove = function(key) {
-  if (this.isEmpty()) {
-    throw Error('Key not found: ' + key);
-  }
-  this.splay_(key);
-  if (this.root_.key != key) {
-    throw Error('Key not found: ' + key);
-  }
-  var removed = this.root_;
-  if (!this.root_.left) {
-    this.root_ = this.root_.right;
-  } else {
-    var right = this.root_.right;
-    this.root_ = this.root_.left;
-    // Splay to make sure that the new root has an empty right child.
-    this.splay_(key);
-    // Insert the original right child as the right child of the new
-    // root.
-    this.root_.right = right;
-  }
-  return removed;
-};
-
-
-/**
- * Returns the node having the specified key or null if the tree doesn't contain
- * a node with the specified key.
- *
- * @param {number} key Key to find in the tree.
- * @return {SplayTree.Node} Node having the specified key.
- */
-SplayTree.prototype.find = function(key) {
-  if (this.isEmpty()) {
-    return null;
-  }
-  this.splay_(key);
-  return this.root_.key == key ? this.root_ : null;
-};
-
-
-/**
- * @return {SplayTree.Node} Node having the maximum key value.
- */
-SplayTree.prototype.findMax = function(opt_startNode) {
-  if (this.isEmpty()) {
-    return null;
-  }
-  var current = opt_startNode || this.root_;
-  while (current.right) {
-    current = current.right;
-  }
-  return current;
-};
-
-
-/**
- * @return {SplayTree.Node} Node having the maximum key value that
- *     is less than the specified key value.
- */
-SplayTree.prototype.findGreatestLessThan = function(key) {
-  if (this.isEmpty()) {
-    return null;
-  }
-  // Splay on the key to move the node with the given key or the last
-  // node on the search path to the top of the tree.
-  this.splay_(key);
-  // Now the result is either the root node or the greatest node in
-  // the left subtree.
-  if (this.root_.key < key) {
-    return this.root_;
-  } else if (this.root_.left) {
-    return this.findMax(this.root_.left);
-  } else {
-    return null;
-  }
-};
-
-
-/**
- * @return {Array<*>} An array containing all the keys of tree's nodes.
- */
-SplayTree.prototype.exportKeys = function() {
-  var result = [];
-  if (!this.isEmpty()) {
-    this.root_.traverse_(function(node) { result.push(node.key); });
-  }
-  return result;
-};
-
-
-/**
- * Perform the splay operation for the given key. Moves the node with
- * the given key to the top of the tree.  If no node has the given
- * key, the last node on the search path is moved to the top of the
- * tree. This is the simplified top-down splaying algorithm from:
- * "Self-adjusting Binary Search Trees" by Sleator and Tarjan
- *
- * @param {number} key Key to splay the tree on.
- * @private
- */
-SplayTree.prototype.splay_ = function(key) {
-  if (this.isEmpty()) {
-    return;
-  }
-  // Create a dummy node.  The use of the dummy node is a bit
-  // counter-intuitive: The right child of the dummy node will hold
-  // the L tree of the algorithm.  The left child of the dummy node
-  // will hold the R tree of the algorithm.  Using a dummy node, left
-  // and right will always be nodes and we avoid special cases.
-  var dummy, left, right;
-  dummy = left = right = new SplayTree.Node(null, null);
-  var current = this.root_;
-  while (true) {
-    if (key < current.key) {
-      if (!current.left) {
-        break;
-      }
-      if (key < current.left.key) {
-        // Rotate right.
-        var tmp = current.left;
-        current.left = tmp.right;
-        tmp.right = current;
-        current = tmp;
-        if (!current.left) {
-          break;
-        }
-      }
-      // Link right.
-      right.left = current;
-      right = current;
-      current = current.left;
-    } else if (key > current.key) {
-      if (!current.right) {
-        break;
-      }
-      if (key > current.right.key) {
-        // Rotate left.
-        var tmp = current.right;
-        current.right = tmp.left;
-        tmp.left = current;
-        current = tmp;
-        if (!current.right) {
-          break;
-        }
-      }
-      // Link left.
-      left.right = current;
-      left = current;
-      current = current.right;
-    } else {
-      break;
-    }
-  }
-  // Assemble.
-  left.right = current.left;
-  right.left = current.right;
-  current.left = dummy.right;
-  current.right = dummy.left;
-  this.root_ = current;
-};
-
-
-/**
- * Constructs a Splay tree node.
- *
- * @param {number} key Key.
- * @param {*} value Value.
- */
-SplayTree.Node = function(key, value) {
-  this.key = key;
-  this.value = value;
-};
-
-
-/**
- * @type {SplayTree.Node}
- */
-SplayTree.Node.prototype.left = null;
-
-
-/**
- * @type {SplayTree.Node}
- */
-SplayTree.Node.prototype.right = null;
-
-
-/**
- * Performs an ordered traversal of the subtree starting at
- * this SplayTree.Node.
- *
- * @param {function(SplayTree.Node)} f Visitor function.
- * @private
- */
-SplayTree.Node.prototype.traverse_ = function(f) {
-  var current = this;
-  while (current) {
-    var left = current.left;
-    if (left) left.traverse_(f);
-    f(current);
-    current = current.right;
-  }
-};