sdk/lib/_internal/compiler/implementation/dump_info.dart - sdk.git - Git at Google

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 library dump_info;

 import 'elements/elements.dart';
 import 'elements/visitor.dart';
 import 'dart:convert' show HtmlEscape;
 import 'dart2jslib.dart' show
     Compiler,
     CompilerTask,
     CodeBuffer;
 import 'dart_types.dart' show DartType;
 import 'types/types.dart' show TypeMask;

 // TODO (sigurdm): A search function.
 // TODO (sigurdm): Output size of classes.
 // TODO (sigurdm): Print that we dumped the HTML-file.
 // TODO (sigurdm): Include why a given element was included in the output.
 // TODO (sigurdm): Include how much output grew because of mirror support.
 // TODO (sigurdm): Write each function with parameter names.
 // TODO (sigurdm): Write how much space the boilerplate takes.
 // TODO (sigurdm): Include javascript names of entities in the output.

 class CodeSizeCounter {
   final Map<Element, int> generatedSize = new Map<Element, int>();

   int getGeneratedSizeOf(Element element) {
     int result = generatedSize[element];
     return result == null ? 0 : result;
   }

   void countCode(Element element, int added) {
     int before = generatedSize.putIfAbsent(element, () => 0);
     generatedSize[element] = before + added;
   }
 }

 tag(String element) {
   return (String content, {String cls}) {
     String classString = cls == null ? '' : ' class="$cls"';
     return '<$element$classString>$content</$element>';
   };
 }

 var div = tag('div');
 var span = tag('span');
 var code = tag('code');
 var h2 = tag('h2');

 var esc = const HtmlEscape().convert;

 String sizeDescription(int size, ProgramInfo programInfo) {
   return size == null
       ? ''
       : span('${size} bytes '
         '(${size * 100 ~/ programInfo.size}%)', cls: "size");
 }

 /// An [InfoNode] holds information about a part the program.
 abstract class InfoNode {
   String get name;

   int get size;

   void emitHtml(ProgramInfo programInfo, StringSink buffer);
 }

 /// An [ElementNode] holds information about an [Element]
 class ElementInfoNode implements InfoNode {
   /// The name of the represented [Element].
   final String name;

   /// The kind of the [Element] represented.  This is presented to the
   /// user, so it might be more specific than [element.kind].
   final String kind;

   /// The static type of the represented [Element].
   /// [null] if this kind of element has no type.
   final String type;

   /// Any extra information to display about the represented [Element].
   final String extra;

   /// A textual description of the modifiers (such as "static", "abstract") of
   /// the represented [Element].
   final String modifiers;

   /// Describes how many bytes the code for the represented [Element] takes up
   /// in the output.
   final int size;

   /// Subnodes containing more detailed information about the represented
   /// [Element], and its members.
   List<InfoNode> contents;

   ElementInfoNode({this.name: "",
       this.kind: "",
       this.type,
       this.modifiers: "",
       this.size,
       this.contents,
       this.extra: ""});

   void emitHtml(ProgramInfo programInfo, StringSink buffer) {
     String kindString = span(esc(kind), cls: 'kind');
     String modifiersString = span(esc(modifiers), cls: "modifiers");

     String nameString = span(esc(name), cls: 'name');
     String typeString = type == null
         ? ''
         : span('/* ' + esc(type) + ' */', cls: 'type');
     String extraString = span(esc(extra), cls: 'type');
     String describe = [
         kindString,
         typeString,
         modifiersString,
         nameString,
         sizeDescription(size, programInfo),
         extraString].join(' ');

     if (contents != null) {
       buffer.write(div("+$describe", cls: "container"));
       buffer.write('<div class="contained">');
       if (contents.isEmpty) {
         buffer.writeln("No members");
       }
       for (InfoNode subElementDescription in contents) {
         subElementDescription.emitHtml(programInfo, buffer);
       }
       buffer.write("</div>");
     } else {
       buffer.writeln(describe);
     }
   }
 }

 /// A [CodeInfoNode] holds information about a piece of code.
 class CodeInfoNode implements InfoNode {
   /// A short description of the code.
   final String description;

   final String generatedCode;

   get size => generatedCode.length;

   get name => "";

   CodeInfoNode({this.description: "", this.generatedCode});

   void emitHtml(ProgramInfo programInfo, StringBuffer buffer) {
     buffer.write(div(description + ' ' +
                      sizeDescription(generatedCode.length, programInfo),
                      cls: 'kind') +
         code(esc(generatedCode)));
   }
 }

 /// Instances represent information inferred about the program such as
 /// inferred type information or inferred side effects.
 class InferredInfoNode implements InfoNode {
   /// Text describing the represented information.
   final String description;

   /// The name of the entity this information is inferred about (for example the
   /// name of a parameter).
   final String name;

   /// The inferred type/side effect.
   final String type;

   get size => 0;

   InferredInfoNode({this.name: "", this.description, this.type});

   void emitHtml(ProgramInfo programInfo, StringSink buffer) {
     buffer.write(div('${span("Inferred " + description, cls: "kind")} '
                      '${span(esc(name),
                      cls: "name")} '
         '${span(esc(type), cls: 'type')} '));
   }
 }

 /// Instances represent information about a program.
 class ProgramInfo {
   /// A list of all the libraries in the program to show information about.
   final List<InfoNode> libraries;

   /// The size of the whole program in bytes.
   final int size;

   /// The time the compilation took place.
   final DateTime compilationMoment;

   /// The time the compilation took to complete.
   final Duration compilationDuration;

   /// The version of dart2js used to compile the program.
   final String dart2jsVersion;

   ProgramInfo({this.libraries,
                this.size,
                this.compilationMoment,
                this.compilationDuration,
                this.dart2jsVersion});
 }

 class InfoDumpVisitor extends ElementVisitor<InfoNode> {
   final Compiler compiler;

   /// Contains the elements visited on the path from the library to here.
   List<Element> stack = new List<Element>();

   Element get currentElement => stack.last;

   InfoDumpVisitor(Compiler this.compiler);

   InfoNode visitElement(Element element) {
     compiler.internalError("This element of kind ${element.kind} "
         "does not support --dump-info",
         token: element.position());
   }

   InfoNode visitLibraryElement(LibraryElement element) {
     List<InfoNode> contents = new List<InfoNode>();
     int size = compiler.dumpInfoTask.codeSizeCounter
         .getGeneratedSizeOf(element);
     if (size == 0) return null;
     stack.add(element);
     element.forEachLocalMember((Element member) {
       InfoNode info = member.accept(this);
       if (info != null) {
         contents.add(info);
       }
     });
     stack.removeLast();
     String nameString = element.getLibraryName() == ""
         ? "<unnamed>"
         : element.getLibraryName();
     contents.sort((InfoNode e1, InfoNode e2) {
       return e1.name.compareTo(e2.name);
     });
     return new ElementInfoNode(
         extra: "${element.canonicalUri}",
         kind: "library",
         name: nameString,
         size: size,
         modifiers: "",
         contents: contents);
   }

   InfoNode visitTypedefElement(TypedefElement element) {
     return element.alias == null
         ? null
         : new ElementInfoNode(
             type: element.alias.toString(),
             kind: "typedef",
             name: element.name);
   }

   InfoNode visitFieldElement(FieldElement element) {
     CodeBuffer emittedCode = compiler.backend.codeOf(element);
     int size = 0;
     DartType type = element.computeType(compiler);
     TypeMask inferredType = compiler.typesTask
         .getGuaranteedTypeOfElement(element);
     // If a field has an empty inferred type it is never used.
     if ((inferredType == null || inferredType.isEmpty) && emittedCode == null) {
       return null;
     }
     List<InfoNode> contents = new List<InfoNode>();
     if (emittedCode != null) {
       contents.add(new CodeInfoNode(
           description: "Generated initializer",
           generatedCode: emittedCode.getText()));
       size = emittedCode.length;
     }
     if (inferredType != null) {
       contents.add(new InferredInfoNode(
           description: "type",
           type: inferredType.toString()));
       stack.add(element);
     }
     for (Element closure in element.nestedClosures) {
       InfoNode info = closure.accept(this);
       if (info != null) {
         contents.add(info);
         size += info.size;
       }
     }
     stack.removeLast();

     return new ElementInfoNode(
         kind: "field",
         type: "$type",
         name: element.name,
         size: size,
         modifiers: "${element.modifiers}",
         contents: contents);
   }

   InfoNode visitClassElement(ClassElement element) {
     // If the element is not resolved it is not used in the program, and we omit
     // it from the output.
     if (!element.isResolved) return null;
     String modifiersString = "${element.modifiers}";
     String supersString = element.allSupertypes == null ? "" :
         "implements ${element.allSupertypes}";
     List contents = [];
     stack.add(element);
     element.forEachLocalMember((Element member) {
       InfoNode info = member.accept(this);
       if (info != null) {
         contents.add(info);
       }
     });
     stack.removeLast();
     if (contents.isEmpty) {
       // TODO (sigurdm): Only return here if the class is never used in type
       // checks.
       return null;
     }
     contents.sort((InfoNode n1, InfoNode n2) {
       return n1.name.compareTo(n2.name);
     });
     return new ElementInfoNode(
         kind: "class",
         name: element.name,
         extra: supersString,
         modifiers: modifiersString,
         contents: contents);
   }

   InfoNode visitFunctionElement(FunctionElement element) {
     CodeBuffer emittedCode = compiler.backend.codeOf(element);
     int size = 0;
     String nameString = element.name;
     String modifiersString = "${element.modifiers}";
     String kindString = "function";
     if (currentElement.isClass()) {
       kindString = "method";
     } else if (currentElement.isField() ||
                currentElement.isFunction() ||
                currentElement.isConstructor()) {
       kindString = "closure";
       nameString = "<unnamed>";
     }
     if (element.isConstructor()) {
       nameString = element.name == ""
           ? "${element.enclosingElement.name}"
           : "${element.enclosingElement.name}.${element.name}";
       kindString = "constructor";
     }
     List contents = [];
     if (emittedCode != null) {
       FunctionSignature signature = element.computeSignature(compiler);
       signature.forEachParameter((parameter) {
         contents.add(new InferredInfoNode(
             description: "parameter",
             name: parameter.name,
             type: compiler.typesTask
               .getGuaranteedTypeOfElement(parameter).toString()));
       });
       contents.add(new InferredInfoNode(
           description: "return type",
           type: compiler.typesTask
             .getGuaranteedReturnTypeOfElement(element).toString()));
       contents.add(new InferredInfoNode(
         description: "side effects",
         type: compiler.world
             .getSideEffectsOfElement(element).toString()));
       contents.add(new CodeInfoNode(
           description: "Generated code",
           generatedCode: emittedCode.getText()));
       size += emittedCode.length;
     }
     stack.add(element);
     for (Element closure in element.nestedClosures) {
       InfoNode info = closure.accept(this);
       if (info != null) {
         contents.add(info);
         size += info.size;
       }
     }
     stack.removeLast();
     if (size == 0) {
       return null;
     }
     return new ElementInfoNode(
         type: element.type.toString(),
         kind: kindString,
         name: nameString,
         size: size,
         modifiers: modifiersString,
         contents: contents);
   }
 }

 class DumpInfoTask extends CompilerTask {
   DumpInfoTask(Compiler compiler)
       : infoDumpVisitor = new InfoDumpVisitor(compiler),
         super(compiler);

   String name = "Dump Info";

   final CodeSizeCounter codeSizeCounter = new CodeSizeCounter();

   final InfoDumpVisitor infoDumpVisitor;

   void dumpInfo() {
     measure(() {
       ProgramInfo info = collectDumpInfo();
       StringBuffer buffer = new StringBuffer();
       dumpInfoHtml(info, buffer);
       compiler.outputProvider('', 'info.html')
         ..add(buffer.toString())
         ..close();
     });
   }

   ProgramInfo collectDumpInfo() {
     List<LibraryElement> sortedLibraries = compiler.libraries.values.toList();
     sortedLibraries.sort((LibraryElement l1, LibraryElement l2) {
       if (l1.isPlatformLibrary && !l2.isPlatformLibrary) {
         return 1;
       } else if (!l1.isPlatformLibrary && l2.isPlatformLibrary) {
         return -1;
       }
       return l1.getLibraryName().compareTo(l2.getLibraryName());
     });

     List<InfoNode> libraryInfos = new List<InfoNode>();
     libraryInfos.addAll(sortedLibraries
         .map((library) => infoDumpVisitor.visit(library))
         .where((info) => info != null));

     return new ProgramInfo(
         compilationDuration: compiler.totalCompileTime.elapsed,
         // TODO (sigurdm): Also count the size of deferred code
         size: compiler.assembledCode.length,
         libraries: libraryInfos,
         compilationMoment: new DateTime.now(),
         dart2jsVersion: compiler.hasBuildId ? compiler.buildId : null);
   }

   void dumpInfoHtml(ProgramInfo info, StringSink buffer) {
     int totalSize = info.size;

     buffer.writeln("""
 <html>
   <head>
     <title>Dart2JS compilation information</title>
        <style>
          code {margin-left: 20px; display: block;}
          div.contained {margin-left: 20px;}
          div {margin-top:0px;
          margin-bottom: 0px;
          white-space: pre; /*border: 1px solid;*/}
          span.kind {}
          span.modifiers {font-weight:bold;}
          span.name {font-weight:bold; font-family: monospace;}
          span.type {font-family: monospace; color:blue;}
        </style>
      </head>
      <body>
        <h1>Dart2js compilation information</h1>""");
     buffer.writeln(h2('Compilation took place: '
                       '${info.compilationMoment}'));
     buffer.writeln(h2('Compilation took: '
                       '${info.compilationDuration.inSeconds} seconds'));
     buffer.writeln(h2('Output size: ${info.size} bytes'));
     if (info.dart2jsVersion != null) {
       buffer.writeln(h2('Dart2js version: ${info.dart2jsVersion}'));
     }

     info.libraries.forEach((InfoNode node) {
       node.emitHtml(info, buffer);
     });


     // TODO (sigurdm): This script should be written in dart
     buffer.writeln(r"""
     <script type="text/javascript">
       function toggler(element) {
         return function(e) {
           element.hidden = !element.hidden;
         };
       }
       var containers = document.getElementsByClassName('container');
       for (var i = 0; i < containers.length; i++) {
         var container = containers[i];
         container.addEventListener('click',
           toggler(container.nextElementSibling), false);
        container.nextElementSibling.hidden = true;
       };
     </script>
   </body>
 </html>""");
   }
 }
	// Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	library dump_info;

	import 'elements/elements.dart';
	import 'elements/visitor.dart';
	import 'dart:convert' show HtmlEscape;
	import 'dart2jslib.dart' show
	Compiler,
	CompilerTask,
	CodeBuffer;
	import 'dart_types.dart' show DartType;
	import 'types/types.dart' show TypeMask;

	// TODO (sigurdm): A search function.
	// TODO (sigurdm): Output size of classes.
	// TODO (sigurdm): Print that we dumped the HTML-file.
	// TODO (sigurdm): Include why a given element was included in the output.
	// TODO (sigurdm): Include how much output grew because of mirror support.
	// TODO (sigurdm): Write each function with parameter names.
	// TODO (sigurdm): Write how much space the boilerplate takes.
	// TODO (sigurdm): Include javascript names of entities in the output.

	class CodeSizeCounter {
	final Map<Element, int> generatedSize = new Map<Element, int>();

	int getGeneratedSizeOf(Element element) {
	int result = generatedSize[element];
	return result == null ? 0 : result;
	}

	void countCode(Element element, int added) {
	int before = generatedSize.putIfAbsent(element, () => 0);
	generatedSize[element] = before + added;
	}
	}

	tag(String element) {
	return (String content, {String cls}) {
	String classString = cls == null ? '' : ' class="$cls"';
	return '<$element$classString>$content</$element>';
	};
	}

	var div = tag('div');
	var span = tag('span');
	var code = tag('code');
	var h2 = tag('h2');

	var esc = const HtmlEscape().convert;

	String sizeDescription(int size, ProgramInfo programInfo) {
	return size == null
	? ''
	: span('${size} bytes '
	'(${size * 100 ~/ programInfo.size}%)', cls: "size");
	}

	/// An [InfoNode] holds information about a part the program.
	abstract class InfoNode {
	String get name;

	int get size;

	void emitHtml(ProgramInfo programInfo, StringSink buffer);
	}

	/// An [ElementNode] holds information about an [Element]
	class ElementInfoNode implements InfoNode {
	/// The name of the represented [Element].
	final String name;

	/// The kind of the [Element] represented. This is presented to the
	/// user, so it might be more specific than [element.kind].
	final String kind;

	/// The static type of the represented [Element].
	/// [null] if this kind of element has no type.
	final String type;

	/// Any extra information to display about the represented [Element].
	final String extra;

	/// A textual description of the modifiers (such as "static", "abstract") of
	/// the represented [Element].
	final String modifiers;

	/// Describes how many bytes the code for the represented [Element] takes up
	/// in the output.
	final int size;

	/// Subnodes containing more detailed information about the represented
	/// [Element], and its members.
	List<InfoNode> contents;

	ElementInfoNode({this.name: "",
	this.kind: "",
	this.type,
	this.modifiers: "",
	this.size,
	this.contents,
	this.extra: ""});

	void emitHtml(ProgramInfo programInfo, StringSink buffer) {
	String kindString = span(esc(kind), cls: 'kind');
	String modifiersString = span(esc(modifiers), cls: "modifiers");

	String nameString = span(esc(name), cls: 'name');
	String typeString = type == null
	? ''
	: span('/* ' + esc(type) + ' */', cls: 'type');
	String extraString = span(esc(extra), cls: 'type');
	String describe = [
	kindString,
	typeString,
	modifiersString,
	nameString,
	sizeDescription(size, programInfo),
	extraString].join(' ');

	if (contents != null) {
	buffer.write(div("+$describe", cls: "container"));
	buffer.write('<div class="contained">');
	if (contents.isEmpty) {
	buffer.writeln("No members");
	}
	for (InfoNode subElementDescription in contents) {
	subElementDescription.emitHtml(programInfo, buffer);
	}
	buffer.write("</div>");
	} else {
	buffer.writeln(describe);
	}
	}
	}

	/// A [CodeInfoNode] holds information about a piece of code.
	class CodeInfoNode implements InfoNode {
	/// A short description of the code.
	final String description;

	final String generatedCode;

	get size => generatedCode.length;

	get name => "";

	CodeInfoNode({this.description: "", this.generatedCode});

	void emitHtml(ProgramInfo programInfo, StringBuffer buffer) {
	buffer.write(div(description + ' ' +
	sizeDescription(generatedCode.length, programInfo),
	cls: 'kind') +
	code(esc(generatedCode)));
	}
	}

	/// Instances represent information inferred about the program such as
	/// inferred type information or inferred side effects.
	class InferredInfoNode implements InfoNode {
	/// Text describing the represented information.
	final String description;

	/// The name of the entity this information is inferred about (for example the
	/// name of a parameter).
	final String name;

	/// The inferred type/side effect.
	final String type;

	get size => 0;

	InferredInfoNode({this.name: "", this.description, this.type});

	void emitHtml(ProgramInfo programInfo, StringSink buffer) {
	buffer.write(div('${span("Inferred " + description, cls: "kind")} '
	'${span(esc(name),
	cls: "name")} '
	'${span(esc(type), cls: 'type')} '));
	}
	}

	/// Instances represent information about a program.
	class ProgramInfo {
	/// A list of all the libraries in the program to show information about.
	final List<InfoNode> libraries;

	/// The size of the whole program in bytes.
	final int size;

	/// The time the compilation took place.
	final DateTime compilationMoment;

	/// The time the compilation took to complete.
	final Duration compilationDuration;

	/// The version of dart2js used to compile the program.
	final String dart2jsVersion;

	ProgramInfo({this.libraries,
	this.size,
	this.compilationMoment,
	this.compilationDuration,
	this.dart2jsVersion});
	}

	class InfoDumpVisitor extends ElementVisitor<InfoNode> {
	final Compiler compiler;

	/// Contains the elements visited on the path from the library to here.
	List<Element> stack = new List<Element>();

	Element get currentElement => stack.last;

	InfoDumpVisitor(Compiler this.compiler);

	InfoNode visitElement(Element element) {
	compiler.internalError("This element of kind ${element.kind} "
	"does not support --dump-info",
	token: element.position());
	}

	InfoNode visitLibraryElement(LibraryElement element) {
	List<InfoNode> contents = new List<InfoNode>();
	int size = compiler.dumpInfoTask.codeSizeCounter
	.getGeneratedSizeOf(element);
	if (size == 0) return null;
	stack.add(element);
	element.forEachLocalMember((Element member) {
	InfoNode info = member.accept(this);
	if (info != null) {
	contents.add(info);
	}
	});
	stack.removeLast();
	String nameString = element.getLibraryName() == ""
	? "<unnamed>"
	: element.getLibraryName();
	contents.sort((InfoNode e1, InfoNode e2) {
	return e1.name.compareTo(e2.name);
	});
	return new ElementInfoNode(
	extra: "${element.canonicalUri}",
	kind: "library",
	name: nameString,
	size: size,
	modifiers: "",
	contents: contents);
	}

	InfoNode visitTypedefElement(TypedefElement element) {
	return element.alias == null
	? null
	: new ElementInfoNode(
	type: element.alias.toString(),
	kind: "typedef",
	name: element.name);
	}

	InfoNode visitFieldElement(FieldElement element) {
	CodeBuffer emittedCode = compiler.backend.codeOf(element);
	int size = 0;
	DartType type = element.computeType(compiler);
	TypeMask inferredType = compiler.typesTask
	.getGuaranteedTypeOfElement(element);
	// If a field has an empty inferred type it is never used.
	if ((inferredType == null \|\| inferredType.isEmpty) && emittedCode == null) {
	return null;
	}
	List<InfoNode> contents = new List<InfoNode>();
	if (emittedCode != null) {
	contents.add(new CodeInfoNode(
	description: "Generated initializer",
	generatedCode: emittedCode.getText()));
	size = emittedCode.length;
	}
	if (inferredType != null) {
	contents.add(new InferredInfoNode(
	description: "type",
	type: inferredType.toString()));
	stack.add(element);
	}
	for (Element closure in element.nestedClosures) {
	InfoNode info = closure.accept(this);
	if (info != null) {
	contents.add(info);
	size += info.size;
	}
	}
	stack.removeLast();

	return new ElementInfoNode(
	kind: "field",
	type: "$type",
	name: element.name,
	size: size,
	modifiers: "${element.modifiers}",
	contents: contents);
	}

	InfoNode visitClassElement(ClassElement element) {
	// If the element is not resolved it is not used in the program, and we omit
	// it from the output.
	if (!element.isResolved) return null;
	String modifiersString = "${element.modifiers}";
	String supersString = element.allSupertypes == null ? "" :
	"implements ${element.allSupertypes}";
	List contents = [];
	stack.add(element);
	element.forEachLocalMember((Element member) {
	InfoNode info = member.accept(this);
	if (info != null) {
	contents.add(info);
	}
	});
	stack.removeLast();
	if (contents.isEmpty) {
	// TODO (sigurdm): Only return here if the class is never used in type
	// checks.
	return null;
	}
	contents.sort((InfoNode n1, InfoNode n2) {
	return n1.name.compareTo(n2.name);
	});
	return new ElementInfoNode(
	kind: "class",
	name: element.name,
	extra: supersString,
	modifiers: modifiersString,
	contents: contents);
	}

	InfoNode visitFunctionElement(FunctionElement element) {
	CodeBuffer emittedCode = compiler.backend.codeOf(element);
	int size = 0;
	String nameString = element.name;
	String modifiersString = "${element.modifiers}";
	String kindString = "function";
	if (currentElement.isClass()) {
	kindString = "method";
	} else if (currentElement.isField() \|\|
	currentElement.isFunction() \|\|
	currentElement.isConstructor()) {
	kindString = "closure";
	nameString = "<unnamed>";
	}
	if (element.isConstructor()) {
	nameString = element.name == ""
	? "${element.enclosingElement.name}"
	: "${element.enclosingElement.name}.${element.name}";
	kindString = "constructor";
	}
	List contents = [];
	if (emittedCode != null) {
	FunctionSignature signature = element.computeSignature(compiler);
	signature.forEachParameter((parameter) {
	contents.add(new InferredInfoNode(
	description: "parameter",
	name: parameter.name,
	type: compiler.typesTask
	.getGuaranteedTypeOfElement(parameter).toString()));
	});
	contents.add(new InferredInfoNode(
	description: "return type",
	type: compiler.typesTask
	.getGuaranteedReturnTypeOfElement(element).toString()));
	contents.add(new InferredInfoNode(
	description: "side effects",
	type: compiler.world
	.getSideEffectsOfElement(element).toString()));
	contents.add(new CodeInfoNode(
	description: "Generated code",
	generatedCode: emittedCode.getText()));
	size += emittedCode.length;
	}
	stack.add(element);
	for (Element closure in element.nestedClosures) {
	InfoNode info = closure.accept(this);
	if (info != null) {
	contents.add(info);
	size += info.size;
	}
	}
	stack.removeLast();
	if (size == 0) {
	return null;
	}
	return new ElementInfoNode(
	type: element.type.toString(),
	kind: kindString,
	name: nameString,
	size: size,
	modifiers: modifiersString,
	contents: contents);
	}
	}

	class DumpInfoTask extends CompilerTask {
	DumpInfoTask(Compiler compiler)
	: infoDumpVisitor = new InfoDumpVisitor(compiler),
	super(compiler);

	String name = "Dump Info";

	final CodeSizeCounter codeSizeCounter = new CodeSizeCounter();

	final InfoDumpVisitor infoDumpVisitor;

	void dumpInfo() {
	measure(() {
	ProgramInfo info = collectDumpInfo();
	StringBuffer buffer = new StringBuffer();
	dumpInfoHtml(info, buffer);
	compiler.outputProvider('', 'info.html')
	..add(buffer.toString())
	..close();
	});
	}

	ProgramInfo collectDumpInfo() {
	List<LibraryElement> sortedLibraries = compiler.libraries.values.toList();
	sortedLibraries.sort((LibraryElement l1, LibraryElement l2) {
	if (l1.isPlatformLibrary && !l2.isPlatformLibrary) {
	return 1;
	} else if (!l1.isPlatformLibrary && l2.isPlatformLibrary) {
	return -1;
	}
	return l1.getLibraryName().compareTo(l2.getLibraryName());
	});

	List<InfoNode> libraryInfos = new List<InfoNode>();
	libraryInfos.addAll(sortedLibraries
	.map((library) => infoDumpVisitor.visit(library))
	.where((info) => info != null));

	return new ProgramInfo(
	compilationDuration: compiler.totalCompileTime.elapsed,
	// TODO (sigurdm): Also count the size of deferred code
	size: compiler.assembledCode.length,
	libraries: libraryInfos,
	compilationMoment: new DateTime.now(),
	dart2jsVersion: compiler.hasBuildId ? compiler.buildId : null);
	}

	void dumpInfoHtml(ProgramInfo info, StringSink buffer) {
	int totalSize = info.size;

	buffer.writeln("""
	<html>
	<head>
	<title>Dart2JS compilation information</title>
	<style>
	code {margin-left: 20px; display: block;}
	div.contained {margin-left: 20px;}
	div {margin-top:0px;
	margin-bottom: 0px;
	white-space: pre; /border: 1px solid;/}
	span.kind {}
	span.modifiers {font-weight:bold;}
	span.name {font-weight:bold; font-family: monospace;}
	span.type {font-family: monospace; color:blue;}
	</style>
	</head>
	<body>
	<h1>Dart2js compilation information</h1>""");
	buffer.writeln(h2('Compilation took place: '
	'${info.compilationMoment}'));
	buffer.writeln(h2('Compilation took: '
	'${info.compilationDuration.inSeconds} seconds'));
	buffer.writeln(h2('Output size: ${info.size} bytes'));
	if (info.dart2jsVersion != null) {
	buffer.writeln(h2('Dart2js version: ${info.dart2jsVersion}'));
	}

	info.libraries.forEach((InfoNode node) {
	node.emitHtml(info, buffer);
	});


	// TODO (sigurdm): This script should be written in dart
	buffer.writeln(r"""
	<script type="text/javascript">
	function toggler(element) {
	return function(e) {
	element.hidden = !element.hidden;
	};
	}
	var containers = document.getElementsByClassName('container');
	for (var i = 0; i < containers.length; i++) {
	var container = containers[i];
	container.addEventListener('click',
	toggler(container.nextElementSibling), false);
	container.nextElementSibling.hidden = true;
	};
	</script>
	</body>
	</html>""");
	}
	}