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			905 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			905 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| //@ skip if $memoryLimited
 | |
| //@ skip if $architecture == "x86"
 | |
| //@ runNoisyTestDefault
 | |
| //@ runNoisyTestNoCJIT
 | |
| 
 | |
| // Copyright 2013 the V8 project authors. All rights reserved.
 | |
| // Copyright (C) 2015 Apple 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.
 | |
| 
 | |
| 
 | |
| // Performance.now is used in latency benchmarks, the fallback is Date.now.
 | |
| var performance = performance || {};
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| performance.now = (function() {
 | |
|   return performance.now       ||
 | |
|          performance.mozNow    ||
 | |
|          performance.msNow     ||
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|          performance.oNow      ||
 | |
|          performance.webkitNow ||
 | |
|          Date.now;
 | |
| })();
 | |
| 
 | |
| // Simple framework for running the benchmark suites and
 | |
| // computing a score based on the timing measurements.
 | |
| 
 | |
| 
 | |
| // A benchmark has a name (string) and a function that will be run to
 | |
| // do the performance measurement. The optional setup and tearDown
 | |
| // arguments are functions that will be invoked before and after
 | |
| // running the benchmark, but the running time of these functions will
 | |
| // not be accounted for in the benchmark score.
 | |
| function Benchmark(name, doWarmup, doDeterministic, run, setup, tearDown, latencyResult, minIterations) {
 | |
|   this.name = name;
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|   this.doWarmup = doWarmup;
 | |
|   this.doDeterministic = doDeterministic;
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|   this.run = run;
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|   this.Setup = setup ? setup : function() { };
 | |
|   this.TearDown = tearDown ? tearDown : function() { };
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|   this.latencyResult = latencyResult ? latencyResult : null; 
 | |
|   this.minIterations = minIterations ? minIterations : 32;
 | |
| }
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| 
 | |
| 
 | |
| // Benchmark results hold the benchmark and the measured time used to
 | |
| // run the benchmark. The benchmark score is computed later once a
 | |
| // full benchmark suite has run to completion. If latency is set to 0
 | |
| // then there is no latency score for this benchmark.
 | |
| function BenchmarkResult(benchmark, time, latency) {
 | |
|   this.benchmark = benchmark;
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|   this.time = time;
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|   this.latency = latency;
 | |
| }
 | |
| 
 | |
| 
 | |
| // Automatically convert results to numbers. Used by the geometric
 | |
| // mean computation.
 | |
| BenchmarkResult.prototype.valueOf = function() {
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|   return this.time;
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| }
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| 
 | |
| 
 | |
| // Suites of benchmarks consist of a name and the set of benchmarks in
 | |
| // addition to the reference timing that the final score will be based
 | |
| // on. This way, all scores are relative to a reference run and higher
 | |
| // scores implies better performance.
 | |
| function BenchmarkSuite(name, reference, benchmarks) {
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|   this.name = name;
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|   this.reference = reference;
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|   this.benchmarks = benchmarks;
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|   BenchmarkSuite.suites.push(this);
 | |
| }
 | |
| 
 | |
| 
 | |
| // Keep track of all declared benchmark suites.
 | |
| BenchmarkSuite.suites = [];
 | |
| 
 | |
| // Scores are not comparable across versions. Bump the version if
 | |
| // you're making changes that will affect that scores, e.g. if you add
 | |
| // a new benchmark or change an existing one.
 | |
| BenchmarkSuite.version = '9';
 | |
| 
 | |
| // Override the alert function to throw an exception instead.
 | |
| alert = function(s) {
 | |
|   throw "Alert called with argument: " + s;
 | |
| };
 | |
| 
 | |
| 
 | |
| // To make the benchmark results predictable, we replace Math.random
 | |
| // with a 100% deterministic alternative.
 | |
| BenchmarkSuite.ResetRNG = function() {
 | |
|   Math.random = (function() {
 | |
|     var seed = 49734321;
 | |
|     return function() {
 | |
|       // Robert Jenkins' 32 bit integer hash function.
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|       seed = ((seed + 0x7ed55d16) + (seed << 12))  & 0xffffffff;
 | |
|       seed = ((seed ^ 0xc761c23c) ^ (seed >>> 19)) & 0xffffffff;
 | |
|       seed = ((seed + 0x165667b1) + (seed << 5))   & 0xffffffff;
 | |
|       seed = ((seed + 0xd3a2646c) ^ (seed << 9))   & 0xffffffff;
 | |
|       seed = ((seed + 0xfd7046c5) + (seed << 3))   & 0xffffffff;
 | |
|       seed = ((seed ^ 0xb55a4f09) ^ (seed >>> 16)) & 0xffffffff;
 | |
|       return (seed & 0xfffffff) / 0x10000000;
 | |
|     };
 | |
|   })();
 | |
| }
 | |
| 
 | |
| 
 | |
| // Runs all registered benchmark suites and optionally yields between
 | |
| // each individual benchmark to avoid running for too long in the
 | |
| // context of browsers. Once done, the final score is reported to the
 | |
| // runner.
 | |
| BenchmarkSuite.RunSuites = function(runner) {
 | |
|   var continuation = null;
 | |
|   var suites = BenchmarkSuite.suites;
 | |
|   var length = suites.length;
 | |
|   BenchmarkSuite.scores = [];
 | |
|   var index = 0;
 | |
|   function RunStep() {
 | |
|     while (continuation || index < length) {
 | |
|       if (continuation) {
 | |
|         continuation = continuation();
 | |
|       } else {
 | |
|         var suite = suites[index++];
 | |
|         if (runner.NotifyStart) runner.NotifyStart(suite.name);
 | |
|         continuation = suite.RunStep(runner);
 | |
|       }
 | |
|       if (continuation && typeof window != 'undefined' && window.setTimeout) {
 | |
|         window.setTimeout(RunStep, 25);
 | |
|         return;
 | |
|       }
 | |
|     }
 | |
| 
 | |
|     // show final result
 | |
|     if (runner.NotifyScore) {
 | |
|       var score = BenchmarkSuite.GeometricMean(BenchmarkSuite.scores);
 | |
|       var formatted = BenchmarkSuite.FormatScore(100 * score);
 | |
|       runner.NotifyScore(formatted);
 | |
|     }
 | |
|   }
 | |
|   RunStep();
 | |
| }
 | |
| 
 | |
| 
 | |
| // Counts the total number of registered benchmarks. Useful for
 | |
| // showing progress as a percentage.
 | |
| BenchmarkSuite.CountBenchmarks = function() {
 | |
|   var result = 0;
 | |
|   var suites = BenchmarkSuite.suites;
 | |
|   for (var i = 0; i < suites.length; i++) {
 | |
|     result += suites[i].benchmarks.length;
 | |
|   }
 | |
|   return result;
 | |
| }
 | |
| 
 | |
| 
 | |
| // Computes the geometric mean of a set of numbers.
 | |
| BenchmarkSuite.GeometricMean = function(numbers) {
 | |
|   var log = 0;
 | |
|   for (var i = 0; i < numbers.length; i++) {
 | |
|     log += Math.log(numbers[i]);
 | |
|   }
 | |
|   return Math.pow(Math.E, log / numbers.length);
 | |
| }
 | |
| 
 | |
| 
 | |
| // Computes the geometric mean of a set of throughput time measurements.
 | |
| BenchmarkSuite.GeometricMeanTime = function(measurements) {
 | |
|   var log = 0;
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|   for (var i = 0; i < measurements.length; i++) {
 | |
|     log += Math.log(measurements[i].time);
 | |
|   }
 | |
|   return Math.pow(Math.E, log / measurements.length);
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| }
 | |
| 
 | |
| 
 | |
| // Computes the average of the worst samples. For example, if percentile is 99, this will report the
 | |
| // average of the worst 1% of the samples.
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| BenchmarkSuite.AverageAbovePercentile = function(numbers, percentile) {
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|   // Don't change the original array.
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|   numbers = numbers.slice();
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|   
 | |
|   // Sort in ascending order.
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|   numbers.sort(function(a, b) { return a - b; });
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|   
 | |
|   // Now the elements we want are at the end. Keep removing them until the array size shrinks too much.
 | |
|   // Examples assuming percentile = 99:
 | |
|   //
 | |
|   // - numbers.length starts at 100: we will remove just the worst entry and then not remove anymore,
 | |
|   //   since then numbers.length / originalLength = 0.99.
 | |
|   //
 | |
|   // - numbers.length starts at 1000: we will remove the ten worst.
 | |
|   //
 | |
|   // - numbers.length starts at 10: we will remove just the worst.
 | |
|   var numbersWeWant = [];
 | |
|   var originalLength = numbers.length;
 | |
|   while (numbers.length / originalLength > percentile / 100)
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|     numbersWeWant.push(numbers.pop());
 | |
|   
 | |
|   var sum = 0;
 | |
|   for (var i = 0; i < numbersWeWant.length; ++i)
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|     sum += numbersWeWant[i];
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|   
 | |
|   var result = sum / numbersWeWant.length;
 | |
|   
 | |
|   // Do a sanity check.
 | |
|   if (numbers.length && result < numbers[numbers.length - 1]) {
 | |
|     throw "Sanity check fail: the worst case result is " + result +
 | |
|       " but we didn't take into account " + numbers;
 | |
|   }
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|   
 | |
|   return result;
 | |
| }
 | |
| 
 | |
| 
 | |
| // Computes the geometric mean of a set of latency measurements.
 | |
| BenchmarkSuite.GeometricMeanLatency = function(measurements) {
 | |
|   var log = 0;
 | |
|   var hasLatencyResult = false;
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|   for (var i = 0; i < measurements.length; i++) {
 | |
|     if (measurements[i].latency != 0) {
 | |
|       log += Math.log(measurements[i].latency);
 | |
|       hasLatencyResult = true;
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|     }
 | |
|   }
 | |
|   if (hasLatencyResult) {
 | |
|     return Math.pow(Math.E, log / measurements.length);
 | |
|   } else {
 | |
|     return 0;
 | |
|   }
 | |
| }
 | |
| 
 | |
| 
 | |
| // Converts a score value to a string with at least three significant
 | |
| // digits.
 | |
| BenchmarkSuite.FormatScore = function(value) {
 | |
|   if (value > 100) {
 | |
|     return value.toFixed(0);
 | |
|   } else {
 | |
|     return value.toPrecision(3);
 | |
|   }
 | |
| }
 | |
| 
 | |
| // Notifies the runner that we're done running a single benchmark in
 | |
| // the benchmark suite. This can be useful to report progress.
 | |
| BenchmarkSuite.prototype.NotifyStep = function(result) {
 | |
|   this.results.push(result);
 | |
|   if (this.runner.NotifyStep) this.runner.NotifyStep(result.benchmark.name);
 | |
| }
 | |
| 
 | |
| 
 | |
| // Notifies the runner that we're done with running a suite and that
 | |
| // we have a result which can be reported to the user if needed.
 | |
| BenchmarkSuite.prototype.NotifyResult = function() {
 | |
|   var mean = BenchmarkSuite.GeometricMeanTime(this.results);
 | |
|   var score = this.reference[0] / mean;
 | |
|   BenchmarkSuite.scores.push(score);
 | |
|   if (this.runner.NotifyResult) {
 | |
|     var formatted = BenchmarkSuite.FormatScore(100 * score);
 | |
|     this.runner.NotifyResult(this.name, formatted);
 | |
|   }
 | |
|   if (this.reference.length == 2) {
 | |
|     var meanLatency = BenchmarkSuite.GeometricMeanLatency(this.results);
 | |
|     if (meanLatency != 0) {
 | |
|       var scoreLatency = this.reference[1] / meanLatency;
 | |
|       BenchmarkSuite.scores.push(scoreLatency);
 | |
|       if (this.runner.NotifyResult) {
 | |
|         var formattedLatency = BenchmarkSuite.FormatScore(100 * scoreLatency)
 | |
|         this.runner.NotifyResult(this.name + "Latency", formattedLatency);
 | |
|       }
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| 
 | |
| // Notifies the runner that running a benchmark resulted in an error.
 | |
| BenchmarkSuite.prototype.NotifyError = function(error) {
 | |
|   if (this.runner.NotifyError) {
 | |
|     this.runner.NotifyError(this.name, error);
 | |
|   }
 | |
|   if (this.runner.NotifyStep) {
 | |
|     this.runner.NotifyStep(this.name);
 | |
|   }
 | |
| }
 | |
| 
 | |
| 
 | |
| // Runs a single benchmark for at least a second and computes the
 | |
| // average time it takes to run a single iteration.
 | |
| BenchmarkSuite.prototype.RunSingleBenchmark = function(benchmark, data) {
 | |
|   function Measure(data) {
 | |
|     var elapsed = 0;
 | |
|     var start = new Date();
 | |
|   
 | |
|   // Run either for 1 second or for the number of iterations specified
 | |
|   // by minIterations, depending on the config flag doDeterministic.
 | |
|     for (var i = 0; (benchmark.doDeterministic ? 
 | |
|       i<benchmark.minIterations : elapsed < 1000); i++) {
 | |
|       benchmark.run();
 | |
|       elapsed = new Date() - start;
 | |
|     }
 | |
|     if (data != null) {
 | |
|       data.runs += i;
 | |
|       data.elapsed += elapsed;
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   // Sets up data in order to skip or not the warmup phase.
 | |
|   if (!benchmark.doWarmup && data == null) {
 | |
|     data = { runs: 0, elapsed: 0 };
 | |
|   }
 | |
| 
 | |
|   if (data == null) {
 | |
|     Measure(null);
 | |
|     return { runs: 0, elapsed: 0 };
 | |
|   } else {
 | |
|     Measure(data);
 | |
|     // If we've run too few iterations, we continue for another second.
 | |
|     if (data.runs < benchmark.minIterations) return data;
 | |
|     var usec = (data.elapsed * 1000) / data.runs;
 | |
|     var latencySamples = (benchmark.latencyResult != null) ? benchmark.latencyResult() : [0];
 | |
|     var percentile = 99.5;
 | |
|     var latency = BenchmarkSuite.AverageAbovePercentile(latencySamples, percentile) * 1000;
 | |
|     this.NotifyStep(new BenchmarkResult(benchmark, usec, latency));
 | |
|     return null;
 | |
|   }
 | |
| }
 | |
| 
 | |
| 
 | |
| // This function starts running a suite, but stops between each
 | |
| // individual benchmark in the suite and returns a continuation
 | |
| // function which can be invoked to run the next benchmark. Once the
 | |
| // last benchmark has been executed, null is returned.
 | |
| BenchmarkSuite.prototype.RunStep = function(runner) {
 | |
|   BenchmarkSuite.ResetRNG();
 | |
|   this.results = [];
 | |
|   this.runner = runner;
 | |
|   var length = this.benchmarks.length;
 | |
|   var index = 0;
 | |
|   var suite = this;
 | |
|   var data;
 | |
| 
 | |
|   // Run the setup, the actual benchmark, and the tear down in three
 | |
|   // separate steps to allow the framework to yield between any of the
 | |
|   // steps.
 | |
| 
 | |
|   function RunNextSetup() {
 | |
|     if (index < length) {
 | |
|       try {
 | |
|         suite.benchmarks[index].Setup();
 | |
|       } catch (e) {
 | |
|         suite.NotifyError(e);
 | |
|         return null;
 | |
|       }
 | |
|       return RunNextBenchmark;
 | |
|     }
 | |
|     suite.NotifyResult();
 | |
|     return null;
 | |
|   }
 | |
| 
 | |
|   function RunNextBenchmark() {
 | |
|     try {
 | |
|       data = suite.RunSingleBenchmark(suite.benchmarks[index], data);
 | |
|     } catch (e) {
 | |
|       suite.NotifyError(e);
 | |
|       return null;
 | |
|     }
 | |
|     // If data is null, we're done with this benchmark.
 | |
|     return (data == null) ? RunNextTearDown : RunNextBenchmark();
 | |
|   }
 | |
| 
 | |
|   function RunNextTearDown() {
 | |
|     try {
 | |
|       suite.benchmarks[index++].TearDown();
 | |
|     } catch (e) {
 | |
|       suite.NotifyError(e);
 | |
|       return null;
 | |
|     }
 | |
|     return RunNextSetup;
 | |
|   }
 | |
| 
 | |
|   // Start out running the setup.
 | |
|   return RunNextSetup();
 | |
| }
 | |
| // Copyright 2009 the V8 project authors. All rights reserved.
 | |
| // Copyright (C) 2015 Apple 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.
 | |
| 
 | |
| // 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, 2739514], [
 | |
|   new Benchmark("Splay", true, false, 
 | |
|     SplayRun, SplaySetup, SplayTearDown, SplayLatency)
 | |
| ]);
 | |
| 
 | |
| 
 | |
| // Configuration.
 | |
| var kSplayTreeSize = 8000;
 | |
| var kSplayTreeModifications = 80;
 | |
| var kSplayTreePayloadDepth = 5;
 | |
| 
 | |
| var splayTree = null;
 | |
| var splaySampleTimeStart = 0.0;
 | |
| 
 | |
| 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();
 | |
| }
 | |
| 
 | |
| var splaySamples = [];
 | |
| 
 | |
| function SplayLatency() {
 | |
|   return splaySamples;
 | |
| }
 | |
| 
 | |
| function SplayUpdateStats(time) {
 | |
|   var pause = time - splaySampleTimeStart;
 | |
|   splaySampleTimeStart = time;
 | |
|   splaySamples.push(pause);
 | |
| }
 | |
| 
 | |
| 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() {
 | |
|   // Check if the platform has the performance.now high resolution timer.
 | |
|   // If not, throw exception and quit.
 | |
|   if (!performance.now) {
 | |
|     throw "PerformanceNowUnsupported";
 | |
|   }
 | |
| 
 | |
|   splayTree = new SplayTree();
 | |
|   splaySampleTimeStart = performance.now()
 | |
|   for (var i = 0; i < kSplayTreeSize; i++) {
 | |
|     InsertNewNode();
 | |
|     if ((i+1) % 20 == 19) {
 | |
|       SplayUpdateStats(performance.now());
 | |
|     }
 | |
|   }
 | |
| }
 | |
| 
 | |
| 
 | |
| 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;
 | |
| 
 | |
|   splaySamples = [];
 | |
| 
 | |
|   // 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);
 | |
|   }
 | |
|   SplayUpdateStats(performance.now());
 | |
| }
 | |
| 
 | |
| 
 | |
| /**
 | |
|  * 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;
 | |
|   }
 | |
| };
 | |
| function jscSetUp() {
 | |
|     SplaySetup();
 | |
| }
 | |
| 
 | |
| function jscTearDown() {
 | |
|     SplayTearDown();
 | |
| }
 | |
| 
 | |
| function jscRun() {
 | |
|     SplayRun();
 | |
| }
 | |
| 
 | |
| jscSetUp();
 | |
| var __before = preciseTime();
 | |
| var times = [];
 | |
| for (var i = 0; i < 2000; ++i) {
 | |
|     var _before = preciseTime();
 | |
|     jscRun();
 | |
|     var _after = preciseTime();
 | |
|     times.push(_after - _before);
 | |
|     flashHeapAccess(1);
 | |
| }
 | |
| var __after = preciseTime();
 | |
| jscTearDown();
 | |
| 
 | |
| function averageAbovePercentile(numbers, percentile) {
 | |
|     // Don't change the original array.
 | |
|     numbers = numbers.slice();
 | |
|     
 | |
|     // Sort in ascending order.
 | |
|     numbers.sort(function(a, b) { return a - b; });
 | |
|     
 | |
|     // Now the elements we want are at the end. Keep removing them until the array size shrinks too much.
 | |
|     // Examples assuming percentile = 99:
 | |
|     //
 | |
|     // - numbers.length starts at 100: we will remove just the worst entry and then not remove anymore,
 | |
|     //   since then numbers.length / originalLength = 0.99.
 | |
|     //
 | |
|     // - numbers.length starts at 1000: we will remove the ten worst.
 | |
|     //
 | |
|     // - numbers.length starts at 10: we will remove just the worst.
 | |
|     var numbersWeWant = [];
 | |
|     var originalLength = numbers.length;
 | |
|     while (numbers.length / originalLength > percentile / 100)
 | |
|         numbersWeWant.push(numbers.pop());
 | |
|     
 | |
|     var sum = 0;
 | |
|     for (var i = 0; i < numbersWeWant.length; ++i)
 | |
|         sum += numbersWeWant[i];
 | |
|     
 | |
|     var result = sum / numbersWeWant.length;
 | |
|     
 | |
|     // Do a sanity check.
 | |
|     if (numbers.length && result < numbers[numbers.length - 1]) {
 | |
|         throw "Sanity check fail: the worst case result is " + result +
 | |
|             " but we didn't take into account " + numbers;
 | |
|     }
 | |
|     
 | |
|     return result;
 | |
| }
 | |
| 
 | |
| print("That took " + (__after - __before) * 1000 + " ms.");
 | |
| 
 | |
| function printPercentile(percentile)
 | |
| {
 | |
|     print("Above " + percentile + "%: " + averageAbovePercentile(times, percentile) * 1000 + " ms.");
 | |
| }
 | |
| 
 | |
| printPercentile(99.9);
 | |
| printPercentile(99.5);
 | |
| printPercentile(99);
 | |
| printPercentile(97.5);
 | |
| printPercentile(95);
 | |
| printPercentile(90);
 | |
| printPercentile(75);
 | |
| printPercentile(50);
 | |
| printPercentile(0);
 | |
| 
 | |
| gc();
 |