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dart / sdk.git / d20e6a536cf012b3a966293179154ef9e0e54934 / . / sdk / lib / _internal / compiler / implementation / js_backend / emitter.dart
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// Copyright (c) 2012, 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.
part of js_backend;
/**
* A function element that represents a closure call. The signature is copied
* from the given element.
*/
class ClosureInvocationElement extends FunctionElementX {
ClosureInvocationElement(SourceString name,
FunctionElement other)
: super.from(name, other, other.enclosingElement),
methodElement = other;
isInstanceMember() => true;
Element getOutermostEnclosingMemberOrTopLevel() => methodElement;
/**
* The [member] this invocation refers to.
*/
Element methodElement;
}
/**
* A convenient type alias for some functions that emit keyed values.
*/
typedef void DefineStubFunction(String invocationName, jsAst.Expression value);
/**
* A data structure for collecting fragments of a class definition.
*/
class ClassBuilder {
final List<jsAst.Property> properties = <jsAst.Property>[];
/// Set to true by user if class is indistinguishable from its superclass.
bool isTrivial = false;
// Has the same signature as [DefineStubFunction].
void addProperty(String name, jsAst.Expression value) {
properties.add(new jsAst.Property(js.string(name), value));
}
jsAst.Expression toObjectInitializer() {
return new jsAst.ObjectInitializer(properties);
}
}
/**
* Generates the code for all used classes in the program. Static fields (even
* in classes) are ignored, since they can be treated as non-class elements.
*
* The code for the containing (used) methods must exist in the [:universe:].
*/
class CodeEmitterTask extends CompilerTask {
bool needsInheritFunction = false;
bool needsDefineClass = false;
bool needsMixinSupport = false;
bool needsLazyInitializer = false;
final Namer namer;
ConstantEmitter constantEmitter;
NativeEmitter nativeEmitter;
CodeBuffer mainBuffer;
final CodeBuffer deferredLibraries = new CodeBuffer();
final CodeBuffer deferredConstants = new CodeBuffer();
/** Shorter access to [isolatePropertiesName]. Both here in the code, as
well as in the generated code. */
String isolateProperties;
String classesCollector;
final Set<ClassElement> neededClasses = new Set<ClassElement>();
final List<ClassElement> regularClasses = <ClassElement>[];
final List<ClassElement> deferredClasses = <ClassElement>[];
final List<ClassElement> nativeClasses = <ClassElement>[];
final List<Selector> trivialNsmHandlers = <Selector>[];
final Map<String, String> mangledFieldNames = <String, String>{};
// TODO(ngeoffray): remove this field.
Set<ClassElement> instantiatedClasses;
final List<jsAst.Expression> boundClosures = <jsAst.Expression>[];
JavaScriptBackend get backend => compiler.backend;
String get _ => compiler.enableMinification ? "" : " ";
String get n => compiler.enableMinification ? "" : "\n";
String get N => compiler.enableMinification ? "\n" : ";\n";
/**
* A cache of closures that are used to closurize instance methods.
* A closure is dynamically bound to the instance used when
* closurized.
*/
final Map<int, String> boundClosureCache;
/**
* A cache of closures that are used to closurize instance methods
* of interceptors. These closures are dynamically bound to the
* interceptor instance, and the actual receiver of the method.
*/
final Map<int, String> interceptorClosureCache;
/**
* Raw ClassElement symbols occuring in is-checks and type assertions. If the
* program contains parameterized checks `x is Set<int>` and
* `x is Set<String>` then the ClassElement `Set` will occur once in
* [checkedClasses].
*/
Set<ClassElement> checkedClasses;
/**
* Raw Typedef symbols occuring in is-checks and type assertions. If the
* program contains `x is F<int>` and `x is F<bool>` then the TypedefElement
* `F` will occur once in [checkedTypedefs].
*/
Set<TypedefElement> checkedTypedefs;
final bool generateSourceMap;
Iterable<ClassElement> cachedClassesUsingTypeVariableTests;
Iterable<ClassElement> get classesUsingTypeVariableTests {
if (cachedClassesUsingTypeVariableTests == null) {
cachedClassesUsingTypeVariableTests = compiler.codegenWorld.isChecks
.where((DartType t) => t is TypeVariableType)
.map((TypeVariableType v) => v.element.getEnclosingClass())
.toList();
}
return cachedClassesUsingTypeVariableTests;
}
CodeEmitterTask(Compiler compiler, Namer namer, this.generateSourceMap)
: mainBuffer = new CodeBuffer(),
this.namer = namer,
boundClosureCache = new Map<int, String>(),
interceptorClosureCache = new Map<int, String>(),
constantEmitter = new ConstantEmitter(compiler, namer),
super(compiler) {
nativeEmitter = new NativeEmitter(this);
}
void addComment(String comment, CodeBuffer buffer) {
buffer.write(jsAst.prettyPrint(js.comment(comment), compiler));
}
void computeRequiredTypeChecks() {
assert(checkedClasses == null && checkedTypedefs == null);
backend.rti.addImplicitChecks(compiler.codegenWorld,
classesUsingTypeVariableTests);
checkedClasses = new Set<ClassElement>();
checkedTypedefs = new Set<TypedefElement>();
compiler.codegenWorld.isChecks.forEach((DartType t) {
if (t is InterfaceType) {
checkedClasses.add(t.element);
} else if (t is TypedefType) {
checkedTypedefs.add(t.element);
}
});
}
ClassElement computeMixinClass(MixinApplicationElement mixinApplication) {
ClassElement mixin = mixinApplication.mixin;
while (mixin.isMixinApplication) {
mixinApplication = mixin;
mixin = mixinApplication.mixin;
}
return mixin;
}
jsAst.Expression constantReference(Constant value) {
return constantEmitter.reference(value);
}
jsAst.Expression constantInitializerExpression(Constant value) {
return constantEmitter.initializationExpression(value);
}
String get name => 'CodeEmitter';
String get currentGenerateAccessorName
=> '${namer.CURRENT_ISOLATE}.\$generateAccessor';
String get generateAccessorHolder
=> '$isolatePropertiesName.\$generateAccessor';
String get finishClassesProperty
=> r'$finishClasses';
String get finishClassesName
=> '${namer.isolateName}.$finishClassesProperty';
String get finishIsolateConstructorName
=> '${namer.isolateName}.\$finishIsolateConstructor';
String get isolatePropertiesName
=> '${namer.isolateName}.${namer.isolatePropertiesName}';
String get supportsProtoName
=> 'supportsProto';
String get lazyInitializerName
=> '${namer.isolateName}.\$lazy';
// Compact field specifications. The format of the field specification is
// <accessorName>:<fieldName><suffix> where the suffix and accessor name
// prefix are optional. The suffix directs the generation of getter and
// setter methods. Each of the getter and setter has two bits to determine
// the calling convention. Setter listed below, getter is similar.
//
// 00: no setter
// 01: function(value) { this.field = value; }
// 10: function(receiver, value) { receiver.field = value; }
// 11: function(receiver, value) { this.field = value; }
//
// The suffix encodes 4 bits using three ASCII ranges of non-identifier
// characters.
static const FIELD_CODE_CHARACTERS = r"<=>?@{|}~%&'()*";
static const NO_FIELD_CODE = 0;
static const FIRST_FIELD_CODE = 1;
static const RANGE1_FIRST = 0x3c; // <=>?@ encodes 1..5
static const RANGE1_LAST = 0x40;
static const RANGE2_FIRST = 0x7b; // {|}~ encodes 6..9
static const RANGE2_LAST = 0x7e;
static const RANGE3_FIRST = 0x25; // %&'()*+ encodes 10..16
static const RANGE3_LAST = 0x2b;
jsAst.FunctionDeclaration get generateAccessorFunction {
const RANGE1_SIZE = RANGE1_LAST - RANGE1_FIRST + 1;
const RANGE2_SIZE = RANGE2_LAST - RANGE2_FIRST + 1;
const RANGE1_ADJUST = - (FIRST_FIELD_CODE - RANGE1_FIRST);
const RANGE2_ADJUST = - (FIRST_FIELD_CODE + RANGE1_SIZE - RANGE2_FIRST);
const RANGE3_ADJUST =
- (FIRST_FIELD_CODE + RANGE1_SIZE + RANGE2_SIZE - RANGE3_FIRST);
String receiverParamName = compiler.enableMinification ? "r" : "receiver";
String valueParamName = compiler.enableMinification ? "v" : "value";
// function generateAccessor(field, prototype) {
jsAst.Fun fun = js.fun(['field', 'prototype'], [
js('var len = field.length'),
js('var code = field.charCodeAt(len - 1)'),
js('code = ((code >= $RANGE1_FIRST) && (code <= $RANGE1_LAST))'
' ? code - $RANGE1_ADJUST'
' : ((code >= $RANGE2_FIRST) && (code <= $RANGE2_LAST))'
' ? code - $RANGE2_ADJUST'
' : ((code >= $RANGE3_FIRST) && (code <= $RANGE3_LAST))'
' ? code - $RANGE3_ADJUST'
' : $NO_FIELD_CODE'),
// if (needsAccessor) {
js.if_('code', [
js('var getterCode = code & 3'),
js('var setterCode = code >> 2'),
js('var accessorName = field = field.substring(0, len - 1)'),
js('var divider = field.indexOf(":")'),
js.if_('divider > 0', [ // Colon never in first position.
js('accessorName = field.substring(0, divider)'),
js('field = field.substring(divider + 1)')
]),
// if (needsGetter) {
js.if_('getterCode', [
js('var args = (getterCode & 2) ? "$receiverParamName" : ""'),
js('var receiver = (getterCode & 1) ? "this" : "$receiverParamName"'),
js('var body = "return " + receiver + "." + field'),
js('prototype["${namer.getterPrefix}" + accessorName] = '
'new Function(args, body)')
]),
// if (needsSetter) {
js.if_('setterCode', [
js('var args = (setterCode & 2)'
' ? "$receiverParamName,${_}$valueParamName"'
' : "$valueParamName"'),
js('var receiver = (setterCode & 1) ? "this" : "$receiverParamName"'),
js('var body = receiver + "." + field + "$_=$_$valueParamName"'),
js('prototype["${namer.setterPrefix}" + accessorName] = '
'new Function(args, body)')
]),
]),
// return field;
js.return_('field')
]);
return new jsAst.FunctionDeclaration(
new jsAst.VariableDeclaration('generateAccessor'),
fun);
}
List get defineClassFunction {
// First the class name, then the field names in an array and the members
// (inside an Object literal).
// The caller can also pass in the constructor as a function if needed.
//
// Example:
// defineClass("A", ["x", "y"], {
// foo$1: function(y) {
// print(this.x + y);
// },
// bar$2: function(t, v) {
// this.x = t - v;
// },
// });
var defineClass = js.fun(['name', 'cls', 'fields', 'prototype'], [
js('var constructor'),
js.if_(js('typeof fields == "function"'), [
js('constructor = fields')
], /* else */ [
js('var str = "function " + cls + "("'),
js('var body = ""'),
js.for_('var i = 0', 'i < fields.length', 'i++', [
js.if_('i != 0', js('str += ", "')),
js('var field = generateAccessor(fields[i], prototype)'),
js('var parameter = "parameter_" + field'),
js('str += parameter'),
js('body += ("this." + field + " = " + parameter + ";\\n")')
]),
js('str += (") {" + body + "}\\nreturn " + cls)'),
js('constructor = new Function(str)()')
]),
js('constructor.prototype = prototype'),
js(r'constructor.builtin$cls = name'),
js.return_('constructor')
]);
// Declare a function called "generateAccessor". This is used in
// defineClassFunction (it's a local declaration in init()).
return [
generateAccessorFunction,
js('$generateAccessorHolder = generateAccessor'),
new jsAst.FunctionDeclaration(
new jsAst.VariableDeclaration('defineClass'), defineClass) ];
}
/** Needs defineClass to be defined. */
List buildProtoSupportCheck() {
// On Firefox and Webkit browsers we can manipulate the __proto__
// directly. Opera claims to have __proto__ support, but it is buggy.
// So we have to do more checks.
// Opera bug was filed as DSK-370158, and fixed as CORE-47615
// (http://my.opera.com/desktopteam/blog/2012/07/20/more-12-01-fixes).
// If the browser does not support __proto__ we need to instantiate an
// object with the correct (internal) prototype set up correctly, and then
// copy the members.
// TODO(8541): Remove this work around.
return [
js('var $supportsProtoName = false'),
js('var tmp = defineClass("c", "c", ["f<"], {}).prototype'),
js.if_(js('tmp.__proto__'), [
js('tmp.__proto__ = {}'),
js.if_(js(r'typeof tmp.get$f != "undefined"'),
js('$supportsProtoName = true'))
])
];
}
static const MAX_MINIFIED_LENGTH_FOR_DIFF_ENCODING = 4;
// If we need fewer than this many noSuchMethod handlers we can save space by
// just emitting them in JS, rather than emitting the JS needed to generate
// them at run time.
static const VERY_FEW_NO_SUCH_METHOD_HANDLERS = 10;
/**
* Adds (at runtime) the handlers to the Object class which catch calls to
* methods that the object does not have. The handlers create an invocation
* mirror object.
*
* The current version only gives you the minified name when minifying (when
* not minifying this method is not called).
*
* In order to generate the noSuchMethod handlers we only need the minified
* name of the method. We test the first character of the minified name to
* determine if it is a getter or a setter, and we use the arguments array at
* runtime to get the number of arguments and their values. If the method
* involves named arguments etc. then we don't handle it here, but emit the
* handler method directly on the Object class.
*
* The minified names are mostly 1-4 character names, which we emit in sorted
* order (primary key is length, secondary ordering is lexicographic). This
* gives an order like ... dD dI dX da ...
*
* Gzip is good with repeated text, but it can't diff-encode, so we do that
* for it. We encode the minified names in a comma-separated string, but all
* the 1-4 character names are encoded before the first comma as a series of
* base 26 numbers. The last digit of each number is lower case, the others
* are upper case, so 1 is "b" and 26 is "Ba".
*
* We think of the minified names as base 88 numbers using the ASCII
* characters from # to z. The base 26 numbers each encode the delta from
* the previous minified name to the next. So if there is a minified name
* called Df and the next is Dh, then they are 2971 and 2973 when thought of
* as base 88 numbers. The difference is 2, which is "c" in lower-case-
* terminated base 26.
*
* The reason we don't encode long minified names with this method is that
* decoding the base 88 numbers would overflow JavaScript's puny integers.
*
* There are some selectors that have a special calling convention (because
* they are called with the receiver as the first argument). They need a
* slightly different noSuchMethod handler, so we handle these first.
*/
void addTrivialNsmHandlers(List<jsAst.Node> statements) {
if (trivialNsmHandlers.length == 0) return;
// Sort by calling convention, JS name length and by JS name.
trivialNsmHandlers.sort((a, b) {
bool aIsIntercepted = backend.isInterceptedName(a.name);
bool bIsIntercepted = backend.isInterceptedName(b.name);
if (aIsIntercepted != bIsIntercepted) return aIsIntercepted ? -1 : 1;
String aName = namer.invocationMirrorInternalName(a);
String bName = namer.invocationMirrorInternalName(b);
if (aName.length != bName.length) return aName.length - bName.length;
return aName.compareTo(bName);
});
// Find out how many selectors there are with the special calling
// convention.
int firstNormalSelector = trivialNsmHandlers.length;
for (int i = 0; i < trivialNsmHandlers.length; i++) {
if (!backend.isInterceptedName(trivialNsmHandlers[i].name)) {
firstNormalSelector = i;
break;
}
}
// Get the short names (JS names, perhaps minified).
Iterable<String> shorts = trivialNsmHandlers.map((selector) =>
namer.invocationMirrorInternalName(selector));
final diffShorts = <String>[];
var diffEncoding = new StringBuffer();
// Treat string as a number in base 88 with digits in ASCII order from # to
// z. The short name sorting is based on length, and uses ASCII order for
// equal length strings so this means that names are ascending. The hash
// character, #, is never given as input, but we need it because it's the
// implicit leading zero (otherwise we could not code names with leading
// dollar signs).
int fromBase88(String x) {
int answer = 0;
for (int i = 0; i < x.length; i++) {
int c = x.codeUnitAt(i);
// No support for Unicode minified identifiers in JS.
assert(c >= $$ && c <= $z);
answer *= 88;
answer += c - $HASH;
}
return answer;
}
// Big endian encoding, A = 0, B = 1...
// A lower case letter terminates the number.
String toBase26(int x) {
int c = x;
var encodingChars = <int>[];
encodingChars.add($a + (c % 26));
while (true) {
c ~/= 26;
if (c == 0) break;
encodingChars.add($A + (c % 26));
}
return new String.fromCharCodes(encodingChars.reversed.toList());
}
bool minify = compiler.enableMinification;
bool useDiffEncoding = minify && shorts.length > 30;
int previous = 0;
int nameCounter = 0;
for (String short in shorts) {
// Emit period that resets the diff base to zero when we switch to normal
// calling convention (this avoids the need to code negative diffs).
if (useDiffEncoding && nameCounter == firstNormalSelector) {
diffEncoding.write(".");
previous = 0;
}
if (short.length <= MAX_MINIFIED_LENGTH_FOR_DIFF_ENCODING &&
useDiffEncoding) {
int base63 = fromBase88(short);
int diff = base63 - previous;
previous = base63;
String base26Diff = toBase26(diff);
diffEncoding.write(base26Diff);
} else {
if (useDiffEncoding || diffEncoding.length != 0) {
diffEncoding.write(",");
}
diffEncoding.write(short);
}
nameCounter++;
}
// Startup code that loops over the method names and puts handlers on the
// Object class to catch noSuchMethod invocations.
ClassElement objectClass = compiler.objectClass;
String createInvocationMirror = namer.getName(
compiler.createInvocationMirrorElement);
String noSuchMethodName = namer.publicInstanceMethodNameByArity(
Compiler.NO_SUCH_METHOD, Compiler.NO_SUCH_METHOD_ARG_COUNT);
var type = 0;
if (useDiffEncoding) {
statements.addAll([
js('var objectClassObject = '
' collectedClasses["${namer.getName(objectClass)}"],'
' shortNames = "$diffEncoding".split(","),'
' nameNumber = 0,'
' diffEncodedString = shortNames[0],'
' calculatedShortNames = [0, 1]'), // 0, 1 are args for splice.
js.for_('var i = 0', 'i < diffEncodedString.length', 'i++', [
js('var codes = [],'
' diff = 0,'
' digit = diffEncodedString.charCodeAt(i)'),
js.if_('digit == ${$PERIOD}', [
js('nameNumber = 0'),
js('digit = diffEncodedString.charCodeAt(++i)')
]),
js.while_('digit <= ${$Z}', [
js('diff *= 26'),
js('diff += (digit - ${$A})'),
js('digit = diffEncodedString.charCodeAt(++i)')
]),
js('diff *= 26'),
js('diff += (digit - ${$a})'),
js('nameNumber += diff'),
js.for_('var remaining = nameNumber',
'remaining > 0',
'remaining = (remaining / 88) | 0', [
js('codes.unshift(${$HASH} + remaining % 88)')
]),
js('calculatedShortNames.push('
' String.fromCharCode.apply(String, codes))')
]),
js('shortNames.splice.apply(shortNames, calculatedShortNames)')
]);
} else {
// No useDiffEncoding version.
Iterable<String> longs = trivialNsmHandlers.map((selector) =>
selector.invocationMirrorMemberName);
String longNamesConstant = minify ? "" :
',longNames = "${longs.join(",")}".split(",")';
statements.add(
js('var objectClassObject = '
' collectedClasses["${namer.getName(objectClass)}"],'
' shortNames = "$diffEncoding".split(",")'
' $longNamesConstant'));
}
String sliceOffset = '," + (j < $firstNormalSelector ? 1 : 0)';
if (firstNormalSelector == 0) sliceOffset = '"';
if (firstNormalSelector == shorts.length) sliceOffset = ', 1"';
String whatToPatch = nativeEmitter.handleNoSuchMethod ?
"Object.prototype" :
"objectClassObject";
statements.addAll([
js.for_('var j = 0', 'j < shortNames.length', 'j++', [
js('var type = 0'),
js('var short = shortNames[j]'),
js.if_('short[0] == "${namer.getterPrefix[0]}"', js('type = 1')),
js.if_('short[0] == "${namer.setterPrefix[0]}"', js('type = 2')),
js('$whatToPatch[short] = Function("'
'return this.$noSuchMethodName('
'this,'
'${namer.CURRENT_ISOLATE}.$createInvocationMirror(\'"'
' + ${minify ? "shortNames" : "longNames"}[j]'
' + "\',\'" + short + "\',"'
' + type'
' + ",Array.prototype.slice.call(arguments'
'$sliceOffset'
' + "),[]))")')
])
]);
}
jsAst.Fun get finishClassesFunction {
// Class descriptions are collected in a JS object.
// 'finishClasses' takes all collected descriptions and sets up
// the prototype.
// Once set up, the constructors prototype field satisfy:
// - it contains all (local) members.
// - its internal prototype (__proto__) points to the superclass'
// prototype field.
// - the prototype's constructor field points to the JavaScript
// constructor.
// For engines where we have access to the '__proto__' we can manipulate
// the object literal directly. For other engines we have to create a new
// object and copy over the members.
List<jsAst.Node> statements = [
js('var pendingClasses = {}'),
js('var hasOwnProperty = Object.prototype.hasOwnProperty'),
js.forIn('cls', 'collectedClasses', [
js.if_('hasOwnProperty.call(collectedClasses, cls)', [
js('var desc = collectedClasses[cls]'),
/* The 'fields' are either a constructor function or a
* string encoding fields, constructor and superclass. Get
* the superclass and the fields in the format
* '[name/]Super;field1,field2'
* from the null-string property on the descriptor.
* The 'name/' is optional and contains the name that should be used
* when printing the runtime type string. It is used, for example, to
* print the runtime type JSInt as 'int'.
*/
js('var classData = desc[""], supr, name = cls, fields = classData'),
optional(
compiler.mirrorsEnabled,
js.if_('typeof classData == "object" && '
'classData instanceof Array',
[js('classData = fields = classData[0]')])),
js.if_('typeof classData == "string"', [
js('var split = classData.split("/")'),
js.if_('split.length == 2', [
js('name = split[0]'),
js('fields = split[1]')
])
]),
js.if_('typeof fields == "string"', [
js('var s = fields.split(";")'),
js('fields = s[1] == "" ? [] : s[1].split(",")'),
js('supr = s[0]'),
], /* else */ [
js('supr = desc.super'),
js.if_(r'!!desc.$name', js(r'name = desc.$name'))
]),
optional(needsMixinSupport, js.if_('supr && supr.indexOf("+") > 0', [
js('s = supr.split("+")'),
js('supr = s[0]'),
js('var mixin = collectedClasses[s[1]]'),
js.forIn('d', 'mixin', [
js.if_('hasOwnProperty.call(mixin, d)'
'&& !hasOwnProperty.call(desc, d)',
js('desc[d] = mixin[d]'))
]),
])),
js('var constructor = defineClass(name, cls, fields, desc)'),
optional(compiler.mirrorsEnabled,
js('constructor["${namer.metadataField}"] = desc')),
js('isolateProperties[cls] = constructor'),
js.if_('supr', js('pendingClasses[cls] = supr'))
])
]),
js('var finishedClasses = {}'),
buildFinishClass(),
];
addTrivialNsmHandlers(statements);
statements.add(
js.forIn('cls', 'pendingClasses', js('finishClass(cls)'))
);
// function(collectedClasses,
// isolateProperties,
// existingIsolateProperties)
return js.fun(['collectedClasses', 'isolateProperties',
'existingIsolateProperties'], statements);
}
jsAst.Node optional(bool condition, jsAst.Node node) {
return condition ? node : new jsAst.EmptyStatement();
}
jsAst.FunctionDeclaration buildFinishClass() {
// function finishClass(cls) {
jsAst.Fun fun = js.fun(['cls'], [
// TODO(8540): Remove this work around.
/* Opera does not support 'getOwnPropertyNames'. Therefore we use
hasOwnProperty instead. */
js('var hasOwnProperty = Object.prototype.hasOwnProperty'),
// if (hasOwnProperty.call(finishedClasses, cls)) return;
js.if_('hasOwnProperty.call(finishedClasses, cls)',
js.return_()),
js('finishedClasses[cls] = true'),
js('var superclass = pendingClasses[cls]'),
// The superclass is only false (empty string) for Dart's Object class.
// The minifier together with noSuchMethod can put methods on the
// Object.prototype object, and they show through here, so we check that
// we have a string.
js.if_('!superclass || typeof superclass != "string"', js.return_()),
js('finishClass(superclass)'),
js('var constructor = isolateProperties[cls]'),
js('var superConstructor = isolateProperties[superclass]'),
js.if_(js('!superConstructor'),
js('superConstructor ='
'existingIsolateProperties[superclass]')),
js('var prototype = constructor.prototype'),
// if ($supportsProtoName) {
js.if_(supportsProtoName, [
js('prototype.__proto__ = superConstructor.prototype'),
js('prototype.constructor = constructor'),
], /* else */ [
// function tmp() {};
new jsAst.FunctionDeclaration(
new jsAst.VariableDeclaration('tmp'),
js.fun([], [])),
js('tmp.prototype = superConstructor.prototype'),
js('var newPrototype = new tmp()'),
js('constructor.prototype = newPrototype'),
js('newPrototype.constructor = constructor'),
// for (var member in prototype) {
js.forIn('member', 'prototype', [
/* Short version of: if (member == '') */
// if (!member) continue;
js.if_('!member', new jsAst.Continue(null)),
// if (hasOwnProperty.call(prototype, member)) {
js.if_('hasOwnProperty.call(prototype, member)', [
js('newPrototype[member] = prototype[member]')
])
])
])
]);
return new jsAst.FunctionDeclaration(
new jsAst.VariableDeclaration('finishClass'),
fun);
}
jsAst.Fun get finishIsolateConstructorFunction {
String isolate = namer.isolateName;
// We replace the old Isolate function with a new one that initializes
// all its field with the initial (and often final) value of all globals.
// This has two advantages:
// 1. the properties are in the object itself (thus avoiding to go through
// the prototype when looking up globals.
// 2. a new isolate goes through a (usually well optimized) constructor
// function of the form: "function() { this.x = ...; this.y = ...; }".
//
// Example: If [isolateProperties] is an object containing: x = 3 and
// A = function A() { /* constructor of class A. */ }, then we generate:
// str = "{
// var isolateProperties = Isolate.$isolateProperties;
// this.x = isolateProperties.x;
// this.A = isolateProperties.A;
// }";
// which is then dynamically evaluated:
// var newIsolate = new Function(str);
//
// We also copy over old values like the prototype, and the
// isolateProperties themselves.
List copyFinishClasses = [];
if (needsDefineClass) {
copyFinishClasses.add(
js('newIsolate.$finishClassesProperty = '
' oldIsolate.$finishClassesProperty'));
}
// function(oldIsolate) {
return js.fun('oldIsolate', [
js('var isolateProperties = oldIsolate.${namer.isolatePropertiesName}'),
js(r'isolateProperties.$currentScript ='
'typeof document == "object" ?'
'(document.currentScript ||'
'document.scripts[document.scripts.length - 1]) :'
'null'),
js('var isolatePrototype = oldIsolate.prototype'),
js('var str = "{\\n"'),
js('str += '
'"var properties = $isolate.${namer.isolatePropertiesName};\\n"'),
js('var hasOwnProperty = Object.prototype.hasOwnProperty'),
// for (var staticName in isolateProperties) {
js.forIn('staticName', 'isolateProperties', [
js.if_('hasOwnProperty.call(isolateProperties, staticName)', [
js('str += ("this." + staticName + "= properties." + staticName + '
'";\\n")')
])
]),
js('str += "}\\n"'),
js('var newIsolate = new Function(str)'),
js('newIsolate.prototype = isolatePrototype'),
js('isolatePrototype.constructor = newIsolate'),
js('newIsolate.${namer.isolatePropertiesName} = isolateProperties'),
// TODO(ahe): Only copy makeConstantList when it is used.
js('newIsolate.makeConstantList = oldIsolate.makeConstantList'),
]..addAll(copyFinishClasses)
..addAll([
// return newIsolate;
js.return_('newIsolate')
]));
}
jsAst.Fun get lazyInitializerFunction {
String isolate = namer.CURRENT_ISOLATE;
// function(prototype, staticName, fieldName, getterName, lazyValue) {
var parameters = <String>['prototype', 'staticName', 'fieldName',
'getterName', 'lazyValue'];
return js.fun(parameters, [
js('var getter = new Function("{ return $isolate." + fieldName + ";}")'),
]..addAll(addLazyInitializerLogic())
);
}
List addLazyInitializerLogic() {
String isolate = namer.CURRENT_ISOLATE;
String cyclicThrow = namer.isolateAccess(backend.getCyclicThrowHelper());
return [
js('var sentinelUndefined = {}'),
js('var sentinelInProgress = {}'),
js('prototype[fieldName] = sentinelUndefined'),
// prototype[getterName] = function()
js('prototype[getterName] = #', js.fun([], [
js('var result = $isolate[fieldName]'),
// try
js.try_([
js.if_('result === sentinelUndefined', [
js('$isolate[fieldName] = sentinelInProgress'),
// try
js.try_([
js('result = $isolate[fieldName] = lazyValue()'),
], finallyPart: [
// Use try-finally, not try-catch/throw as it destroys the
// stack trace.
// if (result === sentinelUndefined)
js.if_('result === sentinelUndefined', [
// if ($isolate[fieldName] === sentinelInProgress)
js.if_('$isolate[fieldName] === sentinelInProgress', [
js('$isolate[fieldName] = null'),
])
])
])
], /* else */ [
js.if_('result === sentinelInProgress',
js('$cyclicThrow(staticName)')
)
]),
// return result;
js.return_('result')
], finallyPart: [
js('$isolate[getterName] = getter')
])
]))
];
}
List buildDefineClassAndFinishClassFunctionsIfNecessary() {
if (!needsDefineClass) return [];
return defineClassFunction
..addAll(buildProtoSupportCheck())
..addAll([
js('$finishClassesName = #', finishClassesFunction)
]);
}
List buildLazyInitializerFunctionIfNecessary() {
if (!needsLazyInitializer) return [];
return [js('$lazyInitializerName = #', lazyInitializerFunction)];
}
List buildFinishIsolateConstructor() {
return [
js('$finishIsolateConstructorName = #', finishIsolateConstructorFunction)
];
}
void emitFinishIsolateConstructorInvocation(CodeBuffer buffer) {
String isolate = namer.isolateName;
buffer.write("$isolate = $finishIsolateConstructorName($isolate)$N");
}
/**
* Generate stubs to handle invocation of methods with optional
* arguments.
*
* A method like [: foo([x]) :] may be invoked by the following
* calls: [: foo(), foo(1), foo(x: 1) :]. See the sources of this
* function for detailed examples.
*/
void addParameterStub(FunctionElement member,
Selector selector,
DefineStubFunction defineStub,
Set<String> alreadyGenerated) {
FunctionSignature parameters = member.computeSignature(compiler);
int positionalArgumentCount = selector.positionalArgumentCount;
if (positionalArgumentCount == parameters.parameterCount) {
assert(selector.namedArgumentCount == 0);
return;
}
if (parameters.optionalParametersAreNamed
&& selector.namedArgumentCount == parameters.optionalParameterCount) {
// If the selector has the same number of named arguments as the element,
// we don't need to add a stub. The call site will hit the method
// directly.
return;
}
ConstantHandler handler = compiler.constantHandler;
List<SourceString> names = selector.getOrderedNamedArguments();
String invocationName = namer.invocationName(selector);
if (alreadyGenerated.contains(invocationName)) return;
alreadyGenerated.add(invocationName);
bool isInterceptedMethod = backend.isInterceptedMethod(member);
// If the method is intercepted, we need to also pass the actual receiver.
int extraArgumentCount = isInterceptedMethod ? 1 : 0;
// Use '$receiver' to avoid clashes with other parameter names. Using
// '$receiver' works because [:namer.safeName:] used for getting parameter
// names never returns a name beginning with a single '$'.
String receiverArgumentName = r'$receiver';
// The parameters that this stub takes.
List<jsAst.Parameter> parametersBuffer =
new List<jsAst.Parameter>(selector.argumentCount + extraArgumentCount);
// The arguments that will be passed to the real method.
List<jsAst.Expression> argumentsBuffer =
new List<jsAst.Expression>(
parameters.parameterCount + extraArgumentCount);
int count = 0;
if (isInterceptedMethod) {
count++;
parametersBuffer[0] = new jsAst.Parameter(receiverArgumentName);
argumentsBuffer[0] = js(receiverArgumentName);
}
int optionalParameterStart = positionalArgumentCount + extraArgumentCount;
// Includes extra receiver argument when using interceptor convention
int indexOfLastOptionalArgumentInParameters = optionalParameterStart - 1;
TreeElements elements =
compiler.enqueuer.resolution.getCachedElements(member);
parameters.orderedForEachParameter((Element element) {
String jsName = backend.namer.safeName(element.name.slowToString());
assert(jsName != receiverArgumentName);
if (count < optionalParameterStart) {
parametersBuffer[count] = new jsAst.Parameter(jsName);
argumentsBuffer[count] = js(jsName);
} else {
int index = names.indexOf(element.name);
if (index != -1) {
indexOfLastOptionalArgumentInParameters = count;
// The order of the named arguments is not the same as the
// one in the real method (which is in Dart source order).
argumentsBuffer[count] = js(jsName);
parametersBuffer[optionalParameterStart + index] =
new jsAst.Parameter(jsName);
// Note that [elements] may be null for a synthesized [member].
} else if (elements != null && elements.isParameterChecked(element)) {
argumentsBuffer[count] = constantReference(SentinelConstant.SENTINEL);
} else {
Constant value = handler.initialVariableValues[element];
if (value == null) {
argumentsBuffer[count] = constantReference(new NullConstant());
} else {
if (!value.isNull()) {
// If the value is the null constant, we should not pass it
// down to the native method.
indexOfLastOptionalArgumentInParameters = count;
}
argumentsBuffer[count] = constantReference(value);
}
}
}
count++;
});
List body;
if (member.hasFixedBackendName()) {
body = nativeEmitter.generateParameterStubStatements(
member, isInterceptedMethod, invocationName,
parametersBuffer, argumentsBuffer,
indexOfLastOptionalArgumentInParameters);
} else {
body = [js.return_(js('this')[namer.getName(member)](argumentsBuffer))];
}
jsAst.Fun function = js.fun(parametersBuffer, body);
defineStub(invocationName, function);
}
void addParameterStubs(FunctionElement member,
DefineStubFunction defineStub) {
// We fill the lists depending on the selector. For example,
// take method foo:
// foo(a, b, {c, d});
//
// We may have multiple ways of calling foo:
// (1) foo(1, 2);
// (2) foo(1, 2, c: 3);
// (3) foo(1, 2, d: 4);
// (4) foo(1, 2, c: 3, d: 4);
// (5) foo(1, 2, d: 4, c: 3);
//
// What we generate at the call sites are:
// (1) foo$2(1, 2);
// (2) foo$3$c(1, 2, 3);
// (3) foo$3$d(1, 2, 4);
// (4) foo$4$c$d(1, 2, 3, 4);
// (5) foo$4$c$d(1, 2, 3, 4);
//
// The stubs we generate are (expressed in Dart):
// (1) foo$2(a, b) => foo$4$c$d(a, b, null, null)
// (2) foo$3$c(a, b, c) => foo$4$c$d(a, b, c, null);
// (3) foo$3$d(a, b, d) => foo$4$c$d(a, b, null, d);
// (4) No stub generated, call is direct.
// (5) No stub generated, call is direct.
// Keep a cache of which stubs have already been generated, to
// avoid duplicates. Note that even if selectors are
// canonicalized, we would still need this cache: a typed selector
// on A and a typed selector on B could yield the same stub.
Set<String> generatedStubNames = new Set<String>();
if (compiler.enabledFunctionApply
&& member.name == namer.closureInvocationSelectorName) {
// If [Function.apply] is called, we pessimistically compile all
// possible stubs for this closure.
FunctionSignature signature = member.computeSignature(compiler);
Set<Selector> selectors = signature.optionalParametersAreNamed
? computeNamedSelectors(signature, member)
: computeOptionalSelectors(signature, member);
for (Selector selector in selectors) {
addParameterStub(member, selector, defineStub, generatedStubNames);
}
} else {
Set<Selector> selectors = compiler.codegenWorld.invokedNames[member.name];
if (selectors == null) return;
for (Selector selector in selectors) {
if (!selector.applies(member, compiler)) continue;
addParameterStub(member, selector, defineStub, generatedStubNames);
}
}
}
/**
* Compute the set of possible selectors in the presence of named
* parameters.
*/
Set<Selector> computeNamedSelectors(FunctionSignature signature,
FunctionElement element) {
Set<Selector> selectors = new Set<Selector>();
// Add the selector that does not have any optional argument.
selectors.add(new Selector(SelectorKind.CALL,
element.name,
element.getLibrary(),
signature.requiredParameterCount,
<SourceString>[]));
// For each optional parameter, we iterator over the set of
// already computed selectors and create new selectors with that
// parameter now being passed.
signature.forEachOptionalParameter((Element element) {
Set<Selector> newSet = new Set<Selector>();
selectors.forEach((Selector other) {
List<SourceString> namedArguments = [element.name];
namedArguments.addAll(other.namedArguments);
newSet.add(new Selector(other.kind,
other.name,
other.library,
other.argumentCount + 1,
namedArguments));
});
selectors.addAll(newSet);
});
return selectors;
}
/**
* Compute the set of possible selectors in the presence of optional
* non-named parameters.
*/
Set<Selector> computeOptionalSelectors(FunctionSignature signature,
FunctionElement element) {
Set<Selector> selectors = new Set<Selector>();
// Add the selector that does not have any optional argument.
selectors.add(new Selector(SelectorKind.CALL,
element.name,
element.getLibrary(),
signature.requiredParameterCount,
<SourceString>[]));
// For each optional parameter, we increment the number of passed
// argument.
for (int i = 1; i <= signature.optionalParameterCount; i++) {
selectors.add(new Selector(SelectorKind.CALL,
element.name,
element.getLibrary(),
signature.requiredParameterCount + i,
<SourceString>[]));
}
return selectors;
}
bool instanceFieldNeedsGetter(Element member) {
assert(member.isField());
if (fieldAccessNeverThrows(member)) return false;
return compiler.mirrorsEnabled
|| compiler.codegenWorld.hasInvokedGetter(member, compiler);
}
bool instanceFieldNeedsSetter(Element member) {
assert(member.isField());
if (fieldAccessNeverThrows(member)) return false;
return (!member.modifiers.isFinalOrConst())
&& (compiler.mirrorsEnabled
|| compiler.codegenWorld.hasInvokedSetter(member, compiler));
}
// We never access a field in a closure (a captured variable) without knowing
// that it is there. Therefore we don't need to use a getter (that will throw
// if the getter method is missing), but can always access the field directly.
static bool fieldAccessNeverThrows(Element element) {
return element is ClosureFieldElement;
}
String compiledFieldName(Element member) {
assert(member.isField());
return member.hasFixedBackendName()
? member.fixedBackendName()
: namer.getName(member);
}
/**
* Documentation wanted -- johnniwinther
*
* Invariant: [member] must be a declaration element.
*/
void addInstanceMember(Element member, ClassBuilder builder) {
assert(invariant(member, member.isDeclaration));
// TODO(floitsch): we don't need to deal with members of
// uninstantiated classes, that have been overwritten by subclasses.
if (member.isFunction()
|| member.isGenerativeConstructorBody()
|| member.isAccessor()) {
if (member.isAbstract(compiler)) return;
jsAst.Expression code = backend.generatedCode[member];
if (code == null) return;
String name = namer.getName(member);
builder.addProperty(name, code);
var metadata = buildMetadataFunction(member);
if (metadata != null) {
builder.addProperty('@$name', metadata);
}
String reflectionName = getReflectionName(member);
if (reflectionName != null) {
builder.addProperty('+$reflectionName', js('0'));
}
code = backend.generatedBailoutCode[member];
if (code != null) {
builder.addProperty(namer.getBailoutName(member), code);
}
FunctionElement function = member;
FunctionSignature parameters = function.computeSignature(compiler);
if (!parameters.optionalParameters.isEmpty) {
addParameterStubs(member, builder.addProperty);
}
} else if (!member.isField()) {
compiler.internalError('unexpected kind: "${member.kind}"',
element: member);
}
emitExtraAccessors(member, builder);
}
String getReflectionName(Element element) {
if (!compiler.mirrorsEnabled) return null;
String name = element.name.slowToString();
if (element.isGetter()) return name;
if (element.isSetter()) return '$name=';
if (element.isFunction()) {
FunctionElement function = element;
int requiredParameterCount = function.requiredParameterCount(compiler);
int optionalParameterCount = function.optionalParameterCount(compiler);
String suffix = '$name:$requiredParameterCount:$optionalParameterCount';
return (function.isConstructor()) ? 'new $suffix' : suffix;
}
if (element.isGenerativeConstructorBody()) {
return null;
}
throw compiler.internalErrorOnElement(
element, 'Do not know how to reflect on this');
}
/**
* Documentation wanted -- johnniwinther
*
* Invariant: [classElement] must be a declaration element.
*/
void emitInstanceMembers(ClassElement classElement,
ClassBuilder builder) {
assert(invariant(classElement, classElement.isDeclaration));
void visitMember(ClassElement enclosing, Element member) {
assert(invariant(classElement, member.isDeclaration));
if (member.isInstanceMember()) {
addInstanceMember(member, builder);
}
}
classElement.implementation.forEachMember(
visitMember,
includeBackendMembers: true);
if (identical(classElement, compiler.objectClass)
&& compiler.enabledNoSuchMethod) {
// Emit the noSuchMethod handlers on the Object prototype now,
// so that the code in the dynamicFunction helper can find
// them. Note that this helper is invoked before analyzing the
// full JS script.
if (!nativeEmitter.handleNoSuchMethod) {
emitNoSuchMethodHandlers(builder.addProperty);
}
}
}
void emitIsTests(ClassElement classElement, ClassBuilder builder) {
assert(invariant(classElement, classElement.isDeclaration));
void generateIsTest(Element other) {
if (other == compiler.objectClass && other != classElement) {
// Avoid emitting [:$isObject:] on all classes but [Object].
return;
}
other = backend.getImplementationClass(other);
builder.addProperty(namer.operatorIs(other), js('true'));
}
void generateSubstitution(Element other, {bool emitNull: false}) {
RuntimeTypes rti = backend.rti;
// TODO(karlklose): support typedefs with variables.
jsAst.Expression expression;
bool needsNativeCheck = nativeEmitter.requiresNativeIsCheck(other);
if (other.kind == ElementKind.CLASS) {
String substitution = rti.getSupertypeSubstitution(classElement, other,
alwaysGenerateFunction: true);
if (substitution != null) {
expression = new jsAst.LiteralExpression(substitution);
} else if (emitNull || needsNativeCheck) {
expression = new jsAst.LiteralNull();
}
}
if (expression != null) {
builder.addProperty(namer.substitutionName(other), expression);
}
}
generateIsTestsOn(classElement, generateIsTest, generateSubstitution);
}
void emitRuntimeTypeSupport(CodeBuffer buffer) {
RuntimeTypes rti = backend.rti;
TypeChecks typeChecks = rti.requiredChecks;
// Add checks to the constructors of instantiated classes.
for (ClassElement cls in typeChecks) {
String holder = namer.isolateAccess(backend.getImplementationClass(cls));
for (TypeCheck check in typeChecks[cls]) {
ClassElement cls = check.cls;
buffer.write('$holder.${namer.operatorIs(cls)}$_=${_}true$N');
Substitution substitution = check.substitution;
if (substitution != null) {
String body = substitution.getCode(rti, false);
buffer.write('$holder.${namer.substitutionName(cls)}$_=${_}$body$N');
}
};
}
}
/**
* Documentation wanted -- johnniwinther
*
* Invariant: [classElement] must be a declaration element.
*/
void visitClassFields(ClassElement classElement,
void addField(Element member,
String name,
String accessorName,
bool needsGetter,
bool needsSetter,
bool needsCheckedSetter)) {
assert(invariant(classElement, classElement.isDeclaration));
// If the class is never instantiated we still need to set it up for
// inheritance purposes, but we can simplify its JavaScript constructor.
bool isInstantiated =
compiler.codegenWorld.instantiatedClasses.contains(classElement);
void visitField(ClassElement enclosingClass, Element member) {
assert(invariant(classElement, member.isDeclaration));
LibraryElement library = member.getLibrary();
SourceString name = member.name;
bool isPrivate = name.isPrivate();
// Keep track of whether or not we're dealing with a field mixin
// into a native class.
bool isMixinNativeField =
classElement.isNative() && enclosingClass.isMixinApplication;
// See if we can dynamically create getters and setters.
// We can only generate getters and setters for [classElement] since
// the fields of super classes could be overwritten with getters or
// setters.
bool needsGetter = false;
bool needsSetter = false;
// We need to name shadowed fields differently, so they don't clash with
// the non-shadowed field.
bool isShadowed = false;
if (isMixinNativeField || identical(enclosingClass, classElement)) {
needsGetter = instanceFieldNeedsGetter(member);
needsSetter = instanceFieldNeedsSetter(member);
} else {
isShadowed = classElement.isShadowedByField(member);
}
if ((isInstantiated && !enclosingClass.isNative())
|| needsGetter
|| needsSetter) {
String accessorName = isShadowed
? namer.shadowedFieldName(member)
: namer.getName(member);
String fieldName = member.hasFixedBackendName()
? member.fixedBackendName()
: (isMixinNativeField ? member.name.slowToString() : accessorName);
bool needsCheckedSetter = false;
if (needsSetter) {
if (compiler.enableTypeAssertions
&& canGenerateCheckedSetter(member)) {
needsCheckedSetter = true;
needsSetter = false;
}
}
// Getters and setters with suffixes will be generated dynamically.
addField(member,
fieldName,
accessorName,
needsGetter,
needsSetter,
needsCheckedSetter);
}
}
// TODO(kasperl): We should make sure to only emit one version of
// overridden fields. Right now, we rely on the ordering so the
// fields pulled in from mixins are replaced with the fields from
// the class definition.
// If a class is not instantiated then we add the field just so we can
// generate the field getter/setter dynamically. Since this is only
// allowed on fields that are in [classElement] we don't need to visit
// superclasses for non-instantiated classes.
classElement.implementation.forEachInstanceField(
visitField,
includeSuperAndInjectedMembers: isInstantiated);
}
void generateGetter(Element member, String fieldName, String accessorName,
ClassBuilder builder) {
String getterName = namer.getterNameFromAccessorName(accessorName);
String receiver = backend.isInterceptorClass(member.getEnclosingClass())
? 'receiver' : 'this';
List<String> args = backend.isInterceptedMethod(member)
? ['receiver']
: [];
builder.addProperty(getterName,
js.fun(args, js.return_(js('$receiver.$fieldName'))));
}
void generateSetter(Element member, String fieldName, String accessorName,
ClassBuilder builder) {
String setterName = namer.setterNameFromAccessorName(accessorName);
String receiver = backend.isInterceptorClass(member.getEnclosingClass())
? 'receiver' : 'this';
List<String> args = backend.isInterceptedMethod(member)
? ['receiver', 'v']
: ['v'];
builder.addProperty(setterName,
js.fun(args, js('$receiver.$fieldName = v')));
}
bool canGenerateCheckedSetter(Element member) {
DartType type = member.computeType(compiler);
if (type.element.isTypeVariable()
|| type.element == compiler.dynamicClass
|| type.element == compiler.objectClass) {
// TODO(ngeoffray): Support type checks on type parameters.
return false;
}
return true;
}
void generateCheckedSetter(Element member,
String fieldName,
String accessorName,
ClassBuilder builder) {
assert(canGenerateCheckedSetter(member));
DartType type = member.computeType(compiler);
// TODO(ahe): Generate a dynamic type error here.
if (type.element.isErroneous()) return;
FunctionElement helperElement
= backend.getCheckedModeHelper(type, typeCast: false);
String helperName = namer.isolateAccess(helperElement);
List<jsAst.Expression> arguments = <jsAst.Expression>[js('v')];
if (helperElement.computeSignature(compiler).parameterCount != 1) {
arguments.add(js.string(namer.operatorIs(type.element)));
}
String setterName = namer.setterNameFromAccessorName(accessorName);
String receiver = backend.isInterceptorClass(member.getEnclosingClass())
? 'receiver' : 'this';
List<String> args = backend.isInterceptedMethod(member)
? ['receiver', 'v']
: ['v'];
builder.addProperty(setterName,
js.fun(args,
js('$receiver.$fieldName = #', js(helperName)(arguments))));
}
void emitClassConstructor(ClassElement classElement, ClassBuilder builder) {
/* Do nothing. */
}
void emitSuper(String superName, ClassBuilder builder) {
/* Do nothing. */
}
void emitRuntimeName(String runtimeName, ClassBuilder builder) {
/* Do nothing. */
}
void recordMangledField(Element member,
String accessorName,
String memberName) {
String previousName = mangledFieldNames.putIfAbsent(
'${namer.getterPrefix}$accessorName',
() => memberName);
assert(invariant(member, previousName == memberName,
message: '$previousName != ${memberName}'));
previousName = mangledFieldNames.putIfAbsent(
'${namer.setterPrefix}$accessorName',
() => '${memberName}=');
assert(invariant(member, previousName == '${memberName}=',
message: '$previousName != ${memberName}='));
}
/// Returns `true` if fields added.
bool emitClassFields(ClassElement classElement,
ClassBuilder builder,
String superName,
{ bool classIsNative: false }) {
assert(superName != null);
String separator = '';
String nativeName = namer.getPrimitiveInterceptorRuntimeName(classElement);
StringBuffer buffer = new StringBuffer();
if (nativeName != null) {
buffer.write('$nativeName/');
}
buffer.write('$superName;');
int bufferClassLength = buffer.length;
var fieldMetadata = [];
bool hasMetadata = false;
visitClassFields(classElement, (Element member,
String name,
String accessorName,
bool needsGetter,
bool needsSetter,
bool needsCheckedSetter) {
// Ignore needsCheckedSetter - that is handled below.
bool needsAccessor = (needsGetter || needsSetter);
// We need to output the fields for non-native classes so we can auto-
// generate the constructor. For native classes there are no
// constructors, so we don't need the fields unless we are generating
// accessors at runtime.
if (!classIsNative || needsAccessor) {
buffer.write(separator);
separator = ',';
if (compiler.mirrorsEnabled) {
var metadata = buildMetadataFunction(member);
if (metadata != null) {
hasMetadata = true;
} else {
metadata = new jsAst.LiteralNull();
}
fieldMetadata.add(metadata);
}
if (compiler.mirrorsEnabled) {
recordMangledField(member, accessorName, member.name.slowToString());
}
if (!needsAccessor) {
// Emit field for constructor generation.
assert(!classIsNative);
buffer.write(name);
} else {
// Emit (possibly renaming) field name so we can add accessors at
// runtime.
buffer.write(accessorName);
if (name != accessorName) {
buffer.write(':$name');
// Only the native classes can have renaming accessors.
assert(classIsNative);
}
int getterCode = 0;
if (needsGetter) {
// 01: function() { return this.field; }
// 10: function(receiver) { return receiver.field; }
// 11: function(receiver) { return this.field; }
getterCode += backend.fieldHasInterceptedGetter(member) ? 2 : 0;
getterCode += backend.isInterceptorClass(classElement) ? 0 : 1;
// TODO(sra): 'isInterceptorClass' might not be the correct test for
// methods forced to use the interceptor convention because the
// method's class was elsewhere mixed-in to an interceptor.
assert(getterCode != 0);
}
int setterCode = 0;
if (needsSetter) {
// 01: function(value) { this.field = value; }
// 10: function(receiver, value) { receiver.field = value; }
// 11: function(receiver, value) { this.field = value; }
setterCode += backend.fieldHasInterceptedSetter(member) ? 2 : 0;
setterCode += backend.isInterceptorClass(classElement) ? 0 : 1;
assert(setterCode != 0);
}
int code = getterCode + (setterCode << 2);
buffer.write(FIELD_CODE_CHARACTERS[code - FIRST_FIELD_CODE]);
}
}
});
bool fieldsAdded = buffer.length > bufferClassLength;
String compactClassData = buffer.toString();
jsAst.Expression classDataNode = js.string(compactClassData);
if (hasMetadata) {
fieldMetadata.insert(0, classDataNode);
classDataNode = new jsAst.ArrayInitializer.from(fieldMetadata);
}
builder.addProperty('', classDataNode);
return fieldsAdded;
}
void emitClassGettersSetters(ClassElement classElement,
ClassBuilder builder) {
visitClassFields(classElement, (Element member,
String name,
String accessorName,
bool needsGetter,
bool needsSetter,
bool needsCheckedSetter) {
compiler.withCurrentElement(member, () {
if (needsCheckedSetter) {
assert(!needsSetter);
generateCheckedSetter(member, name, accessorName, builder);
}
if (!getterAndSetterCanBeImplementedByFieldSpec) {
if (needsGetter) {
generateGetter(member, name, accessorName, builder);
}
if (needsSetter) {
generateSetter(member, name, accessorName, builder);
}
}
});
});
}
/**
* Documentation wanted -- johnniwinther
*
* Invariant: [classElement] must be a declaration element.
*/
void generateClass(ClassElement classElement, CodeBuffer buffer) {
assert(invariant(classElement, classElement.isDeclaration));
assert(invariant(classElement, !classElement.isNative()));
needsDefineClass = true;
String className = namer.getName(classElement);
ClassElement superclass = classElement.superclass;
String superName = "";
if (superclass != null) {
superName = namer.getName(superclass);
}
String runtimeName =
namer.getPrimitiveInterceptorRuntimeName(classElement);
if (classElement.isMixinApplication) {
String mixinName = namer.getName(computeMixinClass(classElement));
superName = '$superName+$mixinName';
needsMixinSupport = true;
}
ClassBuilder builder = new ClassBuilder();
emitClassConstructor(classElement, builder);
emitSuper(superName, builder);
emitRuntimeName(runtimeName, builder);
emitClassFields(classElement, builder, superName);
var metadata = buildMetadataFunction(classElement);
if (metadata != null) {
builder.addProperty("@", metadata);
}
emitClassGettersSetters(classElement, builder);
if (!classElement.isMixinApplication) {
emitInstanceMembers(classElement, builder);
}
emitIsTests(classElement, builder);
// TODO(ahe): This method (generateClass) should return a jsAst.Expression.
if (!buffer.isEmpty) {
buffer.write(',$n$n');
}
buffer.write('$className:$_');
buffer.write(jsAst.prettyPrint(builder.toObjectInitializer(), compiler));
}
bool get getterAndSetterCanBeImplementedByFieldSpec => true;
/// If this is true then we can generate the noSuchMethod handlers at startup
/// time, instead of them being emitted as part of the Object class.
bool get generateTrivialNsmHandlers => true;
int _selectorRank(Selector selector) {
int arity = selector.argumentCount * 3;
if (selector.isGetter()) return arity + 2;
if (selector.isSetter()) return arity + 1;
return arity;
}
int _compareSelectorNames(Selector selector1, Selector selector2) {
String name1 = selector1.name.toString();
String name2 = selector2.name.toString();
if (name1 != name2) return Comparable.compare(name1, name2);
return _selectorRank(selector1) - _selectorRank(selector2);
}
Iterable<Element> getTypedefChecksOn(DartType type) {
bool isSubtype(TypedefElement typedef) {
FunctionType typedefType =
typedef.computeType(compiler).unalias(compiler);
return compiler.types.isSubtype(type, typedefType);
}
return checkedTypedefs.where(isSubtype).toList()
..sort(Elements.compareByPosition);
}
/**
* Generate "is tests" for [cls]: itself, and the "is tests" for the
* classes it implements and type argument substitution functions for these
* tests. We don't need to add the "is tests" of the super class because
* they will be inherited at runtime, but we may need to generate the
* substitutions, because they may have changed.
*/
void generateIsTestsOn(ClassElement cls,
void emitIsTest(Element element),
void emitSubstitution(Element element, {emitNull})) {
if (checkedClasses.contains(cls)) {
emitIsTest(cls);
emitSubstitution(cls);
}
RuntimeTypes rti = backend.rti;
ClassElement superclass = cls.superclass;
bool haveSameTypeVariables(ClassElement a, ClassElement b) {
if (a.isClosure()) return true;
return a.typeVariables == b.typeVariables;
}
if (superclass != null && superclass != compiler.objectClass &&
!haveSameTypeVariables(cls, superclass)) {
// We cannot inherit the generated substitutions, because the type
// variable layout for this class is different. Instead we generate
// substitutions for all checks and make emitSubstitution a NOP for the
// rest of this function.
Set<ClassElement> emitted = new Set<ClassElement>();
// TODO(karlklose): move the computation of these checks to
// RuntimeTypeInformation.
if (backend.needsRti(cls)) {
emitSubstitution(superclass, emitNull: true);
emitted.add(superclass);
}
for (DartType supertype in cls.allSupertypes) {
ClassElement superclass = supertype.element;
if (classesUsingTypeVariableTests.contains(superclass)) {
emitSubstitution(superclass, emitNull: true);
emitted.add(superclass);
}
for (ClassElement check in checkedClasses) {
if (supertype.element == check && !emitted.contains(check)) {
// Generate substitution. If no substitution is necessary, emit
// [:null:] to overwrite a (possibly) existing substitution from the
// super classes.
emitSubstitution(check, emitNull: true);
emitted.add(check);
}
}
}
void emitNothing(_, {emitNull}) {};
emitSubstitution = emitNothing;
}
Set<Element> generated = new Set<Element>();
// A class that defines a [:call:] method implicitly implements
// [Function] and needs checks for all typedefs that are used in is-checks.
if (checkedClasses.contains(compiler.functionClass) ||
!checkedTypedefs.isEmpty) {
Element call = cls.lookupLocalMember(Compiler.CALL_OPERATOR_NAME);
if (call == null) {
// If [cls] is a closure, it has a synthetic call operator method.
call = cls.lookupBackendMember(Compiler.CALL_OPERATOR_NAME);
}
if (call != null && call.isFunction()) {
generateInterfacesIsTests(compiler.functionClass,
emitIsTest,
emitSubstitution,
generated);
getTypedefChecksOn(call.computeType(compiler)).forEach(emitIsTest);
}
}
for (DartType interfaceType in cls.interfaces) {
generateInterfacesIsTests(interfaceType.element, emitIsTest,
emitSubstitution, generated);
}
}
/**
* Generate "is tests" where [cls] is being implemented.
*/
void generateInterfacesIsTests(ClassElement cls,
void emitIsTest(ClassElement element),
void emitSubstitution(ClassElement element),
Set<Element> alreadyGenerated) {
void tryEmitTest(ClassElement check) {
if (!alreadyGenerated.contains(check) && checkedClasses.contains(check)) {
alreadyGenerated.add(check);
emitIsTest(check);
emitSubstitution(check);
}
};
tryEmitTest(cls);
for (DartType interfaceType in cls.interfaces) {
Element element = interfaceType.element;
tryEmitTest(element);
generateInterfacesIsTests(element, emitIsTest, emitSubstitution,
alreadyGenerated);
}
// We need to also emit "is checks" for the superclass and its supertypes.
ClassElement superclass = cls.superclass;
if (superclass != null) {
tryEmitTest(superclass);
generateInterfacesIsTests(superclass, emitIsTest, emitSubstitution,
alreadyGenerated);
}
}
/**
* Return a function that returns true if its argument is a class
* that needs to be emitted.
*/
Function computeClassFilter() {
Set<ClassElement> unneededClasses = new Set<ClassElement>();
// The [Bool] class is not marked as abstract, but has a factory
// constructor that always throws. We never need to emit it.
unneededClasses.add(compiler.boolClass);
// Go over specialized interceptors and then constants to know which
// interceptors are needed.
Set<ClassElement> needed = new Set<ClassElement>();
backend.specializedGetInterceptors.forEach(
(_, Iterable<ClassElement> elements) {
needed.addAll(elements);
}
);
// Add interceptors referenced by constants.
ConstantHandler handler = compiler.constantHandler;
List<Constant> constants = handler.getConstantsForEmission();
for (Constant constant in constants) {
if (constant is InterceptorConstant) {
InterceptorConstant inceptorConstant = constant;
needed.add(inceptorConstant.dispatchedType.element);
}
}
// Add unneeded interceptors to the [unneededClasses] set.
for (ClassElement interceptor in backend.interceptedClasses) {
if (!needed.contains(interceptor)
&& interceptor != compiler.objectClass) {
unneededClasses.add(interceptor);
}
}
return (ClassElement cls) => !unneededClasses.contains(cls);
}
void emitFinishClassesInvocationIfNecessary(CodeBuffer buffer) {
if (needsDefineClass) {
buffer.write('$finishClassesName($classesCollector,'
'$_$isolateProperties,'
'${_}null)$N');
// Reset the map.
buffer.write("$classesCollector$_=${_}null$N$n");
}
}
void emitStaticFunction(CodeBuffer buffer,
String name,
jsAst.Expression functionExpression) {
// TODO(ahe): This method (emitStaticFunction) should return a
// jsAst.Expression.
if (!buffer.isEmpty) {
buffer.write(',$n$n');
}
buffer.write('$name:$_');
buffer.write(jsAst.prettyPrint(functionExpression, compiler));
}
void emitStaticFunctions(CodeBuffer eagerBuffer) {
bool isStaticFunction(Element element) =>
!element.isInstanceMember() && !element.isField();
Iterable<Element> elements =
backend.generatedCode.keys.where(isStaticFunction);
Set<Element> pendingElementsWithBailouts =
backend.generatedBailoutCode.keys
.where(isStaticFunction)
.toSet();
for (Element element in Elements.sortedByPosition(elements)) {
CodeBuffer buffer = bufferForElement(element, eagerBuffer);
jsAst.Expression code = backend.generatedCode[element];
String name = namer.getName(element);
emitStaticFunction(buffer, name, code);
var metadata = buildMetadataFunction(element);
if (metadata != null) {
buffer.write(',$n$n"@$name":$_');
buffer.write(jsAst.prettyPrint(metadata, compiler));
}
jsAst.Expression bailoutCode = backend.generatedBailoutCode[element];
if (bailoutCode != null) {
pendingElementsWithBailouts.remove(element);
emitStaticFunction(buffer, namer.getBailoutName(element), bailoutCode);
}
}
if (!pendingElementsWithBailouts.isEmpty) {
addComment('pendingElementsWithBailouts', eagerBuffer);
}
// Is it possible the primary function was inlined but the bailout was not?
for (Element element in
Elements.sortedByPosition(pendingElementsWithBailouts)) {
CodeBuffer buffer = bufferForElement(element, eagerBuffer);
jsAst.Expression bailoutCode = backend.generatedBailoutCode[element];
emitStaticFunction(buffer, namer.getBailoutName(element), bailoutCode);
}
}
final Map<Element, Element> staticGetters = new Map<Element, Element>();
void emitStaticFunctionGetters(CodeBuffer eagerBuffer) {
for (FunctionElement element in
Elements.sortedByPosition(staticGetters.keys)) {
Element closure = staticGetters[element];
CodeBuffer buffer = isDeferred(element) ? deferredConstants : eagerBuffer;
String closureClass = namer.isolateAccess(closure);
String name = namer.getStaticClosureName(element);
String staticName = namer.getName(element);
String closureName = namer.getStaticClosureName(element);
jsAst.Node assignment = js('$isolateProperties.$name = '
'new $closureClass($isolateProperties.$staticName, "$closureName")');
buffer.write(jsAst.prettyPrint(assignment, compiler));
buffer.write('$N');
}
}
void emitStaticFunctionClosures() {
Set<FunctionElement> functionsNeedingGetter =
compiler.codegenWorld.staticFunctionsNeedingGetter;
for (FunctionElement element in
Elements.sortedByPosition(functionsNeedingGetter)) {
String staticName = namer.getName(element);
String superName = namer.getName(compiler.closureClass);
String name = 'Closure\$${element.name.slowToString()}';
assert(instantiatedClasses.contains(compiler.closureClass));
ClassElement closureClassElement = new ClosureClassElement(
null, new SourceString(name), compiler, element,
element.getCompilationUnit());
// Now add the methods on the closure class. The instance method does not
// have the correct name. Since [addParameterStubs] use the name to create
// its stubs we simply create a fake element with the correct name.
// Note: the callElement will not have any enclosingElement.
FunctionElement callElement =
new ClosureInvocationElement(namer.closureInvocationSelectorName,
element);
String invocationName = namer.instanceMethodName(callElement);
String mangledName = namer.getName(closureClassElement);
// Define the constructor with a name so that Object.toString can
// find the class name of the closure class.
ClassBuilder closureBuilder = new ClassBuilder();
// If a static function is used as a closure we need to add its name
// in case it is used in spawnFunction.
String methodName = namer.STATIC_CLOSURE_NAME_NAME;
emitClosureClassHeader(
mangledName, superName, <String>[invocationName, methodName],
closureBuilder);
addParameterStubs(callElement, closureBuilder.addProperty);
DartType type = element.computeType(compiler);
getTypedefChecksOn(type).forEach((Element typedef) {
String operator = namer.operatorIs(typedef);
closureBuilder.addProperty(operator, js('true'));
});
// TODO(ngeoffray): Cache common base classes for closures, bound
// closures, and static closures that have common type checks.
boundClosures.add(
js('$classesCollector.$mangledName = #',
closureBuilder.toObjectInitializer()));
staticGetters[element] = closureClassElement;
}
}
void emitClosureClassHeader(String mangledName,
String superName,
List<String> fieldNames,
ClassBuilder builder) {
builder.addProperty('',
js.string("$superName;${fieldNames.join(',')}"));
}
/**
* Documentation wanted -- johnniwinther
*
* Invariant: [member] must be a declaration element.
*/
void emitDynamicFunctionGetter(FunctionElement member,
DefineStubFunction defineStub) {
assert(invariant(member, member.isDeclaration));
assert(instantiatedClasses.contains(compiler.boundClosureClass));
// For every method that has the same name as a property-get we create a
// getter that returns a bound closure. Say we have a class 'A' with method
// 'foo' and somewhere in the code there is a dynamic property get of
// 'foo'. Then we generate the following code (in pseudo Dart/JavaScript):
//
// class A {
// foo(x, y, z) { ... } // Original function.
// get foo { return new BoundClosure499(this, "foo"); }
// }
// class BoundClosure499 extends BoundClosure {
// BoundClosure499(this.self, this.name);
// $call3(x, y, z) { return self[name](x, y, z); }
// }
// TODO(floitsch): share the closure classes with other classes
// if they share methods with the same signature. Currently we do this only
// if there are no optional parameters. Closures with optional parameters
// are more difficult to canonicalize because they would need to have the
// same default values.
bool hasOptionalParameters = member.optionalParameterCount(compiler) != 0;
int parameterCount = member.parameterCount(compiler);
Map<int, String> cache;
// Intercepted methods take an extra parameter, which is the
// receiver of the call.
bool inInterceptor = backend.isInterceptedMethod(member);
if (inInterceptor) {
cache = interceptorClosureCache;
} else {
cache = boundClosureCache;
}
List<String> fieldNames = <String>[];
compiler.boundClosureClass.forEachInstanceField((_, Element field) {
fieldNames.add(namer.getName(field));
});
Iterable<Element> typedefChecks =
getTypedefChecksOn(member.computeType(compiler));
bool hasTypedefChecks = !typedefChecks.isEmpty;
bool canBeShared = !hasOptionalParameters && !hasTypedefChecks;
String closureClass = canBeShared ? cache[parameterCount] : null;
if (closureClass == null) {
// Either the class was not cached yet, or there are optional parameters.
// Create a new closure class.
String name;
if (canBeShared) {
if (inInterceptor) {
name = 'BoundClosure\$i${parameterCount}';
} else {
name = 'BoundClosure\$${parameterCount}';
}
} else {
name = 'Bound_${member.name.slowToString()}'
'_${member.enclosingElement.name.slowToString()}';
}
ClassElement closureClassElement = new ClosureClassElement(
null, new SourceString(name), compiler, member,
member.getCompilationUnit());
String mangledName = namer.getName(closureClassElement);
String superName = namer.getName(closureClassElement.superclass);
// Define the constructor with a name so that Object.toString can
// find the class name of the closure class.
ClassBuilder boundClosureBuilder = new ClassBuilder();
emitClosureClassHeader(
mangledName, superName, fieldNames, boundClosureBuilder);
// Now add the methods on the closure class. The instance method does not
// have the correct name. Since [addParameterStubs] use the name to create
// its stubs we simply create a fake element with the correct name.
// Note: the callElement will not have any enclosingElement.
FunctionElement callElement =
new ClosureInvocationElement(namer.closureInvocationSelectorName,
member);
String invocationName = namer.instanceMethodName(callElement);
List<String> parameters = <String>[];
List<jsAst.Expression> arguments = <jsAst.Expression>[];
if (inInterceptor) {
arguments.add(js('this')[fieldNames[2]]);
}
for (int i = 0; i < parameterCount; i++) {
String name = 'p$i';
parameters.add(name);
arguments.add(js(name));
}
jsAst.Expression fun = js.fun(
parameters,
js.return_(
js('this')[fieldNames[0]][js('this')[fieldNames[1]]](arguments)));
boundClosureBuilder.addProperty(invocationName, fun);
addParameterStubs(callElement, boundClosureBuilder.addProperty);
typedefChecks.forEach((Element typedef) {
String operator = namer.operatorIs(typedef);
boundClosureBuilder.addProperty(operator, js('true'));
});
boundClosures.add(
js('$classesCollector.$mangledName = #',
boundClosureBuilder.toObjectInitializer()));
closureClass = namer.isolateAccess(closureClassElement);
// Cache it.
if (canBeShared) {
cache[parameterCount] = closureClass;
}
}
// And finally the getter.
String getterName = namer.getterName(member);
String targetName = namer.instanceMethodName(member);
List<String> parameters = <String>[];
List<jsAst.Expression> arguments = <jsAst.Expression>[];
arguments.add(js('this'));
arguments.add(js.string(targetName));
if (inInterceptor) {
String receiverArg = fieldNames[2];
parameters.add(receiverArg);
arguments.add(js(receiverArg));
} else {
// Put null in the intercepted receiver field.
arguments.add(new jsAst.LiteralNull());
}
jsAst.Expression getterFunction = js.fun(
parameters,
js.return_(js(closureClass).newWith(arguments)));
defineStub(getterName, getterFunction);
}
/**
* Documentation wanted -- johnniwinther
*
* Invariant: [member] must be a declaration element.
*/
void emitCallStubForGetter(Element member,
Set<Selector> selectors,
DefineStubFunction defineStub) {
assert(invariant(member, member.isDeclaration));
LibraryElement memberLibrary = member.getLibrary();
// If the method is intercepted, the stub gets the
// receiver explicitely and we need to pass it to the getter call.
bool isInterceptedMethod = backend.isInterceptedMethod(member);
const String receiverArgumentName = r'$receiver';
jsAst.Expression buildGetter() {
if (member.isGetter()) {
String getterName = namer.getterName(member);
return js('this')[getterName](
isInterceptedMethod
? <jsAst.Expression>[js(receiverArgumentName)]
: <jsAst.Expression>[]);
} else {
String fieldName = member.hasFixedBackendName()
? member.fixedBackendName()
: namer.instanceFieldName(member);
return js('this')[fieldName];
}
}
// Two selectors may match but differ only in type. To avoid generating
// identical stubs for each we track untyped selectors which already have
// stubs.
Set<Selector> generatedSelectors = new Set<Selector>();
for (Selector selector in selectors) {
if (selector.applies(member, compiler)) {
selector = selector.asUntyped;
if (generatedSelectors.contains(selector)) continue;
generatedSelectors.add(selector);
String invocationName = namer.invocationName(selector);
Selector callSelector = new Selector.callClosureFrom(selector);
String closureCallName = namer.invocationName(callSelector);
List<jsAst.Parameter> parameters = <jsAst.Parameter>[];
List<jsAst.Expression> arguments = <jsAst.Expression>[];
if (isInterceptedMethod) {
parameters.add(new jsAst.Parameter(receiverArgumentName));
}
for (int i = 0; i < selector.argumentCount; i++) {
String name = 'arg$i';
parameters.add(new jsAst.Parameter(name));
arguments.add(js(name));
}
jsAst.Fun function = js.fun(
parameters,
js.return_(buildGetter()[closureCallName](arguments)));
defineStub(invocationName, function);
}
}
}
void emitStaticNonFinalFieldInitializations(CodeBuffer buffer) {
ConstantHandler handler = compiler.constantHandler;
Iterable<VariableElement> staticNonFinalFields =
handler.getStaticNonFinalFieldsForEmission();
for (Element element in Elements.sortedByPosition(staticNonFinalFields)) {
// [:interceptedNames:] is handled in [emitInterceptedNames].
if (element == backend.interceptedNames) continue;
compiler.withCurrentElement(element, () {
Constant initialValue = handler.getInitialValueFor(element);
jsAst.Expression init =
js('$isolateProperties.${namer.getName(element)} = #',
constantEmitter.referenceInInitializationContext(initialValue));
buffer.write(jsAst.prettyPrint(init, compiler));
buffer.write('$N');
});
}
}
void emitLazilyInitializedStaticFields(CodeBuffer buffer) {
ConstantHandler handler = compiler.constantHandler;
List<VariableElement> lazyFields =
handler.getLazilyInitializedFieldsForEmission();
if (!lazyFields.isEmpty) {
needsLazyInitializer = true;
for (VariableElement element in Elements.sortedByPosition(lazyFields)) {
assert(backend.generatedBailoutCode[element] == null);
jsAst.Expression code = backend.generatedCode[element];
// The code is null if we ended up not needing the lazily
// initialized field after all because of constant folding
// before code generation.
if (code == null) continue;
// The code only computes the initial value. We build the lazy-check
// here:
// lazyInitializer(prototype, 'name', fieldName, getterName, initial);
// The name is used for error reporting. The 'initial' must be a
// closure that constructs the initial value.
List<jsAst.Expression> arguments = <jsAst.Expression>[];
arguments.add(js(isolateProperties));
arguments.add(js.string(element.name.slowToString()));
arguments.add(js.string(namer.getName(element)));
arguments.add(js.string(namer.getLazyInitializerName(element)));
arguments.add(code);
jsAst.Expression getter = buildLazyInitializedGetter(element);
if (getter != null) {
arguments.add(getter);
}
jsAst.Expression init = js(lazyInitializerName)(arguments);
buffer.write(jsAst.prettyPrint(init, compiler));
buffer.write("$N");
}
}
}
jsAst.Expression buildLazyInitializedGetter(VariableElement element) {
// Nothing to do, the 'lazy' function will create the getter.
return null;
}
void emitCompileTimeConstants(CodeBuffer eagerBuffer) {
ConstantHandler handler = compiler.constantHandler;
List<Constant> constants = handler.getConstantsForEmission();
bool addedMakeConstantList = false;
for (Constant constant in constants) {
// No need to emit functions. We already did that.
if (constant.isFunction()) continue;
// Numbers, strings and booleans are currently always inlined.
if (constant.isPrimitive()) continue;
String name = namer.constantName(constant);
// The name is null when the constant is already a JS constant.
// TODO(floitsch): every constant should be registered, so that we can
// share the ones that take up too much space (like some strings).
if (name == null) continue;
if (!addedMakeConstantList && constant.isList()) {
addedMakeConstantList = true;
emitMakeConstantList(eagerBuffer);
}
CodeBuffer buffer = bufferForConstant(constant, eagerBuffer);
jsAst.Expression init = js('$isolateProperties.$name = #',
constantInitializerExpression(constant));
buffer.write(jsAst.prettyPrint(init, compiler));
buffer.write('$N');
}
}
void emitMakeConstantList(CodeBuffer buffer) {
buffer.write(namer.isolateName);
buffer.write(r'''.makeConstantList = function(list) {
list.immutable$list = true;
list.fixed$length = true;
return list;
};
''');
}
/**
* Documentation wanted -- johnniwinther
*
* Invariant: [member] must be a declaration element.
*/
void emitExtraAccessors(Element member, ClassBuilder builder) {
assert(invariant(member, member.isDeclaration));
if (member.isGetter() || member.isField()) {
Set<Selector> selectors = compiler.codegenWorld.invokedNames[member.name];
if (selectors != null && !selectors.isEmpty) {
emitCallStubForGetter(member, selectors, builder.addProperty);
}
} else if (member.isFunction()) {
if (compiler.codegenWorld.hasInvokedGetter(member, compiler)) {
emitDynamicFunctionGetter(member, builder.addProperty);
}
}
}
// Identify the noSuchMethod handlers that are so simple that we can
// generate them programatically.
bool isTrivialNsmHandler(
int type, List argNames, Selector selector, String internalName) {
if (!generateTrivialNsmHandlers) return false;
// Check for interceptor calling convention.
if (backend.isInterceptedName(selector.name)) {
// We can handle the calling convention used by intercepted names in the
// diff encoding, but we don't use that for non-minified code.
if (!compiler.enableMinification) return false;
String shortName = namer.invocationMirrorInternalName(selector);
if (shortName.length > MAX_MINIFIED_LENGTH_FOR_DIFF_ENCODING) {
return false;
}
}
// Check for named arguments.
if (argNames.length != 0) return false;
// Check for unexpected name (this doesn't really happen).
if (internalName.startsWith(namer.getterPrefix[0])) return type == 1;
if (internalName.startsWith(namer.setterPrefix[0])) return type == 2;
return type == 0;
}
void emitNoSuchMethodHandlers(DefineStubFunction defineStub) {
// Do not generate no such method handlers if there is no class.
if (compiler.codegenWorld.instantiatedClasses.isEmpty) return;
String noSuchMethodName = namer.publicInstanceMethodNameByArity(
Compiler.NO_SUCH_METHOD, Compiler.NO_SUCH_METHOD_ARG_COUNT);
Element createInvocationMirrorElement =
compiler.findHelper(const SourceString("createInvocationMirror"));
String createInvocationMirrorName =
namer.getName(createInvocationMirrorElement);
// Keep track of the JavaScript names we've already added so we
// do not introduce duplicates (bad for code size).
Map<String, Selector> addedJsNames = new Map<String, Selector>();
void addNoSuchMethodHandlers(SourceString ignore, Set<Selector> selectors) {
// Cache the object class and type.
ClassElement objectClass = compiler.objectClass;
DartType objectType = objectClass.computeType(compiler);
for (Selector selector in selectors) {
// If the selector is typed, we check to see if that type may
// have a user-defined noSuchMethod implementation. If not, we
// skip the selector altogether.
TypeMask mask = selector.mask;
if (mask == null) {
mask = new TypeMask.subclass(compiler.objectClass.rawType);
}
// If the receiver is guaranteed to have a member that
// matches what we're looking for, there's no need to
// introduce a noSuchMethod handler. It will never be called.
//
// As an example, consider this class hierarchy:
//
// A <-- noSuchMethod
// / \
// C B <-- foo
//
// If we know we're calling foo on an object of type B we
// don't have to worry about the noSuchMethod method in A
// because objects of type B implement foo. On the other hand,
// if we end up calling foo on something of type C we have to
// add a handler for it.
// If the holders of all user-defined noSuchMethod
// implementations that might be applicable to the receiver
// type have a matching member for the current name and
// selector, we avoid introducing a noSuchMethod handler.
//
// As an example, consider this class hierarchy:
//
// A <-- foo
// / \
// noSuchMethod --> B C <-- bar
// | |
// C D <-- noSuchMethod
//
// When calling foo on an object of type A, we know that the
// implementations of noSuchMethod are in the classes B and D
// that also (indirectly) implement foo, so we do not need a
// handler for it.
//
// If we're calling bar on an object of type D, we don't need
// the handler either because all objects of type D implement
// bar through inheritance.
//
// If we're calling bar on an object of type A we do need the
// handler because we may have to call B.noSuchMethod since B
// does not implement bar.
if (mask.willHit(selector, compiler)) continue;
String jsName = namer.invocationMirrorInternalName(selector);
addedJsNames[jsName] = selector;
}
}
compiler.codegenWorld.invokedNames.forEach(addNoSuchMethodHandlers);
compiler.codegenWorld.invokedGetters.forEach(addNoSuchMethodHandlers);
compiler.codegenWorld.invokedSetters.forEach(addNoSuchMethodHandlers);
// Set flag used by generateMethod helper below. If we have very few
// handlers we use defineStub for them all, rather than try to generate them
// at runtime.
bool haveVeryFewNoSuchMemberHandlers =
(addedJsNames.length < VERY_FEW_NO_SUCH_METHOD_HANDLERS);
jsAst.Expression generateMethod(String jsName, Selector selector) {
// Values match JSInvocationMirror in js-helper library.
int type = selector.invocationMirrorKind;
List<jsAst.Parameter> parameters = <jsAst.Parameter>[];
CodeBuffer args = new CodeBuffer();
for (int i = 0; i < selector.argumentCount; i++) {
parameters.add(new jsAst.Parameter('\$$i'));
}
List<jsAst.Expression> argNames =
selector.getOrderedNamedArguments().map((SourceString name) =>
js.string(name.slowToString())).toList();
String methodName = selector.invocationMirrorMemberName;
String internalName = namer.invocationMirrorInternalName(selector);
if (!haveVeryFewNoSuchMemberHandlers &&
isTrivialNsmHandler(type, argNames, selector, internalName)) {
trivialNsmHandlers.add(selector);
return null;
}
String createInvocationMirror = namer.getName(
compiler.createInvocationMirrorElement);
assert(backend.isInterceptedName(Compiler.NO_SUCH_METHOD));
jsAst.Expression expression = js('this.$noSuchMethodName')(
[js('this'),
js(namer.CURRENT_ISOLATE)[createInvocationMirror]([
js.string(compiler.enableMinification ?
internalName : methodName),
js.string(internalName),
type,
new jsAst.ArrayInitializer.from(
parameters.map((param) => js(param.name)).toList()),
new jsAst.ArrayInitializer.from(argNames)])]);
parameters = backend.isInterceptedName(selector.name)
? ([new jsAst.Parameter('\$receiver')]..addAll(parameters))
: parameters;
return js.fun(parameters, js.return_(expression));
}
for (String jsName in addedJsNames.keys.toList()..sort()) {
Selector selector = addedJsNames[jsName];
jsAst.Expression method = generateMethod(jsName, selector);
if (method != null) defineStub(jsName, method);
}
}
String buildIsolateSetup(CodeBuffer buffer,
Element appMain,
Element isolateMain) {
String mainAccess = "${namer.isolateStaticClosureAccess(appMain)}";
String currentIsolate = "${namer.CURRENT_ISOLATE}";
// Since we pass the closurized version of the main method to
// the isolate method, we must make sure that it exists.
return "${namer.isolateAccess(isolateMain)}($mainAccess)";
}
String get nameOfDispatchPropertyInitializer => 'initializeDispatchProperty';
jsAst.Expression generateDispatchPropertyInitialization() {
String ref(Element element) {
return '${namer.CURRENT_ISOLATE}.${namer.getName(element)}';
}
return js(ref(backend.initializeDispatchPropertyMethod))([
js.fun(['a'], [ js('${ref(backend.getDispatchPropertyMethod)} = a')]),
js.string(generateDispatchPropertyName(0)),
js('${ref(backend.jsInterceptorClass)}.prototype')
]);
}
String generateDispatchPropertyName(int seed) {
// TODO(sra): MD5 of contributing source code or URIs?
return '___dart_dispatch_record_ZxYxX_${seed}_';
}
emitMain(CodeBuffer buffer) {
if (compiler.isMockCompilation) return;
Element main = compiler.mainApp.find(Compiler.MAIN);
String mainCall = null;
if (compiler.hasIsolateSupport()) {
Element isolateMain =
compiler.isolateHelperLibrary.find(Compiler.START_ROOT_ISOLATE);
mainCall = buildIsolateSetup(buffer, main, isolateMain);
} else {
mainCall = '${namer.isolateAccess(main)}()';
}
if (backend.needToInitializeDispatchProperty) {
buffer.write(
jsAst.prettyPrint(generateDispatchPropertyInitialization(),
compiler));
buffer.write(N);
}
addComment('BEGIN invoke [main].', buffer);
buffer.write("""
if (typeof document !== "undefined" && document.readyState !== "complete") {
document.addEventListener("readystatechange", function () {
if (document.readyState == "complete") {
if (typeof dartMainRunner === "function") {
dartMainRunner(function() { ${mainCall}; });
} else {
${mainCall};
}
}
}, false);
} else {
if (typeof dartMainRunner === "function") {
dartMainRunner(function() { ${mainCall}; });
} else {
${mainCall};
}
}
""");
addComment('END invoke [main].', buffer);
}
void emitGetInterceptorMethod(CodeBuffer buffer,
String key,
Iterable<ClassElement> classes) {
jsAst.Statement buildReturnInterceptor(ClassElement cls) {
return js.return_(js(namer.isolateAccess(cls))['prototype']);
}
/**
* Build a JavaScrit AST node for doing a type check on
* [cls]. [cls] must be an interceptor class.
*/
jsAst.Statement buildInterceptorCheck(ClassElement cls) {
jsAst.Expression condition;
assert(backend.isInterceptorClass(cls));
if (cls == backend.jsBoolClass) {
condition = js('(typeof receiver) == "boolean"');
} else if (cls == backend.jsIntClass ||
cls == backend.jsDoubleClass ||
cls == backend.jsNumberClass) {
throw 'internal error';
} else if (cls == backend.jsArrayClass ||
cls == backend.jsMutableArrayClass ||
cls == backend.jsFixedArrayClass ||
cls == backend.jsExtendableArrayClass) {
condition = js('receiver.constructor == Array');
} else if (cls == backend.jsStringClass) {
condition = js('(typeof receiver) == "string"');
} else if (cls == backend.jsNullClass) {
condition = js('receiver == null');
} else {
throw 'internal error';
}
return js.if_(condition, buildReturnInterceptor(cls));
}
bool hasArray = false;
bool hasBool = false;
bool hasDouble = false;
bool hasInt = false;
bool hasNull = false;
bool hasNumber = false;
bool hasString = false;
bool hasNative = false;
for (ClassElement cls in classes) {
if (cls == backend.jsArrayClass ||
cls == backend.jsMutableArrayClass ||
cls == backend.jsFixedArrayClass ||
cls == backend.jsExtendableArrayClass) hasArray = true;
else if (cls == backend.jsBoolClass) hasBool = true;
else if (cls == backend.jsDoubleClass) hasDouble = true;
else if (cls == backend.jsIntClass) hasInt = true;
else if (cls == backend.jsNullClass) hasNull = true;
else if (cls == backend.jsNumberClass) hasNumber = true;
else if (cls == backend.jsStringClass) hasString = true;
else {
// TODO(sra): The set of classes includes classes mixed-in to
// interceptor classes.
// assert(cls == compiler.objectClass || cls.isNative());
if (cls.isNative()) hasNative = true;
}
}
if (hasDouble) {
hasNumber = true;
}
if (hasInt) hasNumber = true;
if (classes == backend.interceptedClasses) {
// I.e. this is the general interceptor.
hasNative = compiler.enqueuer.codegen.nativeEnqueuer.hasNativeClasses();
}
jsAst.Block block = new jsAst.Block.empty();
if (hasNumber) {
jsAst.Statement whenNumber;
/// Note: there are two number classes in play: Dart's [num],
/// and JavaScript's Number (typeof receiver == 'number'). This
/// is the fallback used when we have determined that receiver
/// is a JavaScript Number.
jsAst.Return returnNumberClass = buildReturnInterceptor(
hasDouble ? backend.jsDoubleClass : backend.jsNumberClass);
if (hasInt) {
jsAst.Expression isInt = js('Math.floor(receiver) == receiver');
whenNumber = js.block([
js.if_(isInt, buildReturnInterceptor(backend.jsIntClass)),
returnNumberClass]);
} else {
whenNumber = returnNumberClass;
}
block.statements.add(
js.if_('(typeof receiver) == "number"',
whenNumber));
}
if (hasString) {
block.statements.add(buildInterceptorCheck(backend.jsStringClass));
}
if (hasNull) {
block.statements.add(buildInterceptorCheck(backend.jsNullClass));
} else {
// Returning "undefined" or "null" here will provoke a JavaScript
// TypeError which is later identified as a null-error by
// [unwrapException] in js_helper.dart.
block.statements.add(js.if_('receiver == null',
js.return_(js('receiver'))));
}
if (hasBool) {
block.statements.add(buildInterceptorCheck(backend.jsBoolClass));
}
// TODO(ahe): It might be faster to check for Array before
// function and bool.
if (hasArray) {
block.statements.add(buildInterceptorCheck(backend.jsArrayClass));
}
if (hasNative) {
block.statements.add(
js.if_(
js('(typeof receiver) != "object"'),
js.return_(js('receiver'))));
// if (receiver instanceof $.Object) return receiver;
// return $.getNativeInterceptor(receiver);
block.statements.add(
js.if_(js('receiver instanceof #',
js(namer.isolateAccess(compiler.objectClass))),
js.return_(js('receiver'))));
// TODO(sra): Fold this 'Object' check into the `getNativeInterceptor`
// check by patching `Object.prototype` with a special hook function.
// TODO(9556): This test is needed in plain non-browser code because
// 'holders' are not Dart classes.
block.statements.add(
js.if_(
js('Object.getPrototypeOf(receiver) === Object.prototype'),
buildReturnInterceptor(backend.jsInterceptorClass)));
block.statements.add(
js.return_(
js(namer.isolateAccess(backend.getNativeInterceptorMethod))(
['receiver'])));
} else {
ClassElement jsUnknown = backend.jsUnknownClass;
if (compiler.codegenWorld.instantiatedClasses.contains(jsUnknown)) {
block.statements.add(
js.if_(js('!(receiver instanceof #)',
js(namer.isolateAccess(compiler.objectClass))),
buildReturnInterceptor(jsUnknown)));
}
block.statements.add(js.return_(js('receiver')));
}
buffer.write(jsAst.prettyPrint(
js('$isolateProperties.$key = #', js.fun(['receiver'], block)),
compiler));
buffer.write(N);
}
/**
* Emit all versions of the [:getInterceptor:] method.
*/
void emitGetInterceptorMethods(CodeBuffer buffer) {
var specializedGetInterceptors = backend.specializedGetInterceptors;
for (String name in specializedGetInterceptors.keys.toList()..sort()) {
Iterable<ClassElement> classes = specializedGetInterceptors[name];
emitGetInterceptorMethod(buffer, name, classes);
}
}
/**
* Compute all the classes that must be emitted.
*/
void computeNeededClasses() {
instantiatedClasses =
compiler.codegenWorld.instantiatedClasses.where(computeClassFilter())
.toSet();
void addClassWithSuperclasses(ClassElement cls) {
neededClasses.add(cls);
for (ClassElement superclass = cls.superclass;
superclass != null;
superclass = superclass.superclass) {
neededClasses.add(superclass);
}
}
void addClassesWithSuperclasses(Iterable<ClassElement> classes) {
for (ClassElement cls in classes) {
addClassWithSuperclasses(cls);
}
}
// 1. We need to generate all classes that are instantiated.
addClassesWithSuperclasses(instantiatedClasses);
// 2. Add all classes used as mixins.
Set<ClassElement> mixinClasses = neededClasses
.where((ClassElement element) => element.isMixinApplication)
.map(computeMixinClass)
.toSet();
neededClasses.addAll(mixinClasses);
// 3a. Add classes that are referenced by type arguments or substitutions in
// argument checks.
// TODO(karlklose): merge this case with 3b when unifying argument and
// object checks.
RuntimeTypes rti = backend.rti;
backend.rti.getRequiredArgumentClasses(backend).forEach((ClassElement c) {
// Types that we represent with JS native types (like int and String) do
// not need a class definition as we use the interceptor classes instead.
if (!rti.isJsNative(c)) {
addClassWithSuperclasses(c);
}
});
// 3b. Add classes that are referenced by substitutions in object checks and
// their superclasses.
TypeChecks requiredChecks =
backend.rti.computeChecks(neededClasses, checkedClasses);
Set<ClassElement> classesUsedInSubstitutions =
rti.getClassesUsedInSubstitutions(backend, requiredChecks);
addClassesWithSuperclasses(classesUsedInSubstitutions);
// 4. Finally, sort the classes.
List<ClassElement> sortedClasses = Elements.sortedByPosition(neededClasses);
// If we need noSuchMethod support, we run through all needed
// classes to figure out if we need the support on any native
// class. If so, we let the native emitter deal with it.
if (compiler.enabledNoSuchMethod) {
SourceString noSuchMethodName = Compiler.NO_SUCH_METHOD;
Selector noSuchMethodSelector = compiler.noSuchMethodSelector;
for (ClassElement element in sortedClasses) {
if (!element.isNative()) continue;
Element member = element.lookupLocalMember(noSuchMethodName);
if (member == null) continue;
if (noSuchMethodSelector.applies(member, compiler)) {
nativeEmitter.handleNoSuchMethod = true;
break;
}
}
}
for (ClassElement element in sortedClasses) {
if (element.isNative()) {
// For now, native classes cannot be deferred.
nativeClasses.add(element);
} else if (isDeferred(element)) {
deferredClasses.add(element);
} else {
regularClasses.add(element);
}
}
}
// Optimize performance critical one shot interceptors.
jsAst.Statement tryOptimizeOneShotInterceptor(Selector selector,
Set<ClassElement> classes) {
jsAst.Expression isNumber(String variable) {
return js('typeof $variable == "number"');
}
jsAst.Expression isNotObject(String variable) {
return js('typeof $variable != "object"');
}
jsAst.Expression isInt(String variable) {
return isNumber(variable).binary('&&',
js('Math.floor($variable) == $variable'));
}
jsAst.Expression tripleShiftZero(jsAst.Expression receiver) {
return receiver.binary('>>>', js('0'));
}
if (selector.isOperator()) {
String name = selector.name.stringValue;
if (name == '==') {
// Unfolds to:
// [: if (receiver == null) return a0 == null;
// if (typeof receiver != 'object') {
// return a0 != null && receiver === a0;
// }
// :].
List<jsAst.Statement> body = <jsAst.Statement>[];
body.add(js.if_('receiver == null', js.return_(js('a0 == null'))));
body.add(js.if_(
isNotObject('receiver'),
js.return_(js('a0 != null && receiver === a0'))));
return new jsAst.Block(body);
}
if (!classes.contains(backend.jsIntClass)
&& !classes.contains(backend.jsNumberClass)
&& !classes.contains(backend.jsDoubleClass)) {
return null;
}
if (selector.argumentCount == 1) {
// The following operators do not map to a JavaScript
// operator.
if (name != '~/' && name != '<<' && name != '%' && name != '>>') {
jsAst.Expression result = js('receiver').binary(name, js('a0'));
if (name == '&' || name == '|' || name == '^') {
result = tripleShiftZero(result);
}
// Unfolds to:
// [: if (typeof receiver == "number" && typeof a0 == "number")
// return receiver op a0;
// :].
return js.if_(
isNumber('receiver').binary('&&', isNumber('a0')),
js.return_(result));
}
} else if (name == 'unary-') {
// operator~ does not map to a JavaScript operator.
// Unfolds to:
// [: if (typeof receiver == "number") return -receiver:].
return js.if_(isNumber('receiver'),
js.return_(js('-receiver')));
} else {
assert(name == '~');
return js.if_(isInt('receiver'),
js.return_(js('~receiver >>> 0')));
}
} else if (selector.isIndex() || selector.isIndexSet()) {
// For an index operation, this code generates:
//
// [: if (receiver.constructor == Array || typeof receiver == "string") {
// if (a0 >>> 0 === a0 && a0 < receiver.length) {
// return receiver[a0];
// }
// }
// :]
//
// For an index set operation, this code generates:
//
// [: if (receiver.constructor == Array && !receiver.immutable$list) {
// if (a0 >>> 0 === a0 && a0 < receiver.length) {
// return receiver[a0] = a1;
// }
// }
// :]
bool containsArray = classes.contains(backend.jsArrayClass);
bool containsString = classes.contains(backend.jsStringClass);
// The index set operator requires a check on its set value in
// checked mode, so we don't optimize the interceptor if the
// compiler has type assertions enabled.
if (selector.isIndexSet()
&& (compiler.enableTypeAssertions || !containsArray)) {
return null;
}
if (!containsArray && !containsString) {
return null;
}
jsAst.Expression isIntAndAboveZero = js('a0 >>> 0 === a0');
jsAst.Expression belowLength = js('a0 < receiver.length');
jsAst.Expression arrayCheck = js('receiver.constructor == Array');
if (selector.isIndex()) {
jsAst.Expression stringCheck = js('typeof receiver == "string"');
jsAst.Expression typeCheck;
if (containsArray) {
if (containsString) {
typeCheck = arrayCheck.binary('||', stringCheck);
} else {
typeCheck = arrayCheck;
}
} else {
assert(containsString);
typeCheck = stringCheck;
}
return js.if_(typeCheck,
js.if_(isIntAndAboveZero.binary('&&', belowLength),
js.return_(js('receiver[a0]'))));
} else {
jsAst.Expression isImmutableArray = arrayCheck.binary(
'&&', js(r'!receiver.immutable$list'));
return js.if_(isImmutableArray.binary(
'&&', isIntAndAboveZero.binary('&&', belowLength)),
js.return_(js('receiver[a0] = a1')));
}
}
return null;
}
void emitOneShotInterceptors(CodeBuffer buffer) {
List<String> names = backend.oneShotInterceptors.keys.toList();
names.sort();
for (String name in names) {
Selector selector = backend.oneShotInterceptors[name];
Set<ClassElement> classes =
backend.getInterceptedClassesOn(selector.name);
String getInterceptorName =
namer.getInterceptorName(backend.getInterceptorMethod, classes);
List<jsAst.Parameter> parameters = <jsAst.Parameter>[];
List<jsAst.Expression> arguments = <jsAst.Expression>[];
parameters.add(new jsAst.Parameter('receiver'));
arguments.add(js('receiver'));
if (selector.isSetter()) {
parameters.add(new jsAst.Parameter('value'));
arguments.add(js('value'));
} else {
for (int i = 0; i < selector.argumentCount; i++) {
String argName = 'a$i';
parameters.add(new jsAst.Parameter(argName));
arguments.add(js(argName));
}
}
List<jsAst.Statement> body = <jsAst.Statement>[];
jsAst.Statement optimizedPath =
tryOptimizeOneShotInterceptor(selector, classes);
if (optimizedPath != null) {
body.add(optimizedPath);
}
String invocationName = backend.namer.invocationName(selector);
body.add(js.return_(
js(isolateProperties)[getInterceptorName]('receiver')[invocationName](
arguments)));
jsAst.Expression assignment =
js('$isolateProperties.$name = #', js.fun(parameters, body));
buffer.write(jsAst.prettyPrint(assignment, compiler));
buffer.write(N);
}
}
/**
* If [JSInvocationMirror._invokeOn] has been compiled, emit all the
* possible selector names that are intercepted into the
* [interceptedNames] top-level variable. The implementation of
* [_invokeOn] will use it to determine whether it should call the
* method with an extra parameter.
*/
void emitInterceptedNames(CodeBuffer buffer) {
if (!compiler.enabledInvokeOn) return;
String name = backend.namer.getName(backend.interceptedNames);
int index = 0;
List<jsAst.ArrayElement> elements = backend.usedInterceptors.map(
(Selector selector) {
jsAst.Literal str = js.string(namer.invocationName(selector));
return new jsAst.ArrayElement(index++, str);
}).toList();
jsAst.ArrayInitializer array = new jsAst.ArrayInitializer(
backend.usedInterceptors.length,
elements);
jsAst.Expression assignment = js('$isolateProperties.$name = #', array);
buffer.write(jsAst.prettyPrint(assignment, compiler));
buffer.write(N);
}
void emitInitFunction(CodeBuffer buffer) {
jsAst.Fun fun = js.fun([], [
js('$isolateProperties = {}'),
]
..addAll(buildDefineClassAndFinishClassFunctionsIfNecessary())
..addAll(buildLazyInitializerFunctionIfNecessary())
..addAll(buildFinishIsolateConstructor())
);
jsAst.FunctionDeclaration decl = new jsAst.FunctionDeclaration(
new jsAst.VariableDeclaration('init'), fun);
buffer.write(jsAst.prettyPrint(decl, compiler).getText());
if (compiler.enableMinification) buffer.write('\n');
}
/// The metadata function returns the metadata associated with
/// [element] in generated code. The metadata needs to be wrapped
/// in a function as it refers to constants that may not have been
/// constructed yet. For example, a class is allowed to be
/// annotated with itself. The metadata function is used by
/// mirrors_patch to implement DeclarationMirror.metadata.
jsAst.Fun buildMetadataFunction(Element element) {
if (!compiler.mirrorsEnabled) return null;
var metadata = [];
Link link = element.metadata;
// TODO(ahe): Why is metadata sometimes null?
if (link != null) {
for (; !link.isEmpty; link = link.tail) {
metadata.add(constantReference(link.head.value));
}
}
if (metadata.isEmpty) return null;
return js.fun([], [js.return_(new jsAst.ArrayInitializer.from(metadata))]);
}
String assembleProgram() {
measure(() {
// Compute the required type checks to know which classes need a
// 'is$' method.
computeRequiredTypeChecks();
computeNeededClasses();
mainBuffer.add(buildGeneratedBy());
addComment(HOOKS_API_USAGE, mainBuffer);
mainBuffer.add('function ${namer.isolateName}()$_{}\n');
mainBuffer.add('init()$N$n');
// Shorten the code by using [namer.CURRENT_ISOLATE] as temporary.
isolateProperties = namer.CURRENT_ISOLATE;
mainBuffer.add(
'var $isolateProperties$_=$_$isolatePropertiesName$N');
if (!regularClasses.isEmpty ||
!deferredClasses.isEmpty ||
!nativeClasses.isEmpty ||
!compiler.codegenWorld.staticFunctionsNeedingGetter.isEmpty) {
// Shorten the code by using "$$" as temporary.
classesCollector = r"$$";
mainBuffer.add('var $classesCollector$_=$_{}$N$n');
}
// As a side-effect, emitting classes will produce "bound closures" in
// [boundClosures]. The bound closures are JS AST nodes that add
// properties to $$ [classesCollector]. The bound closures are not
// emitted until we have emitted all other classes (native or not).
// Might create boundClosures.
if (!regularClasses.isEmpty) {
for (ClassElement element in regularClasses) {
generateClass(element, bufferForElement(element, mainBuffer));
}
}
// Emit native classes on [nativeBuffer].
// Might create boundClosures.
final CodeBuffer nativeBuffer = new CodeBuffer();
if (!nativeClasses.isEmpty) {
addComment('Native classes', nativeBuffer);
addComment('Native classes', mainBuffer);
nativeEmitter.generateNativeClasses(nativeClasses, mainBuffer);
}
nativeEmitter.finishGenerateNativeClasses();
nativeEmitter.assembleCode(nativeBuffer);
// Might create boundClosures.
if (!deferredClasses.isEmpty) {
for (ClassElement element in deferredClasses) {
generateClass(element, bufferForElement(element, mainBuffer));
}
}
emitStaticFunctionClosures();
addComment('Bound closures', mainBuffer);
// Now that we have emitted all classes, we know all the bound
// closures that will be needed.
for (jsAst.Node node in boundClosures) {
// TODO(ahe): Some of these can be deferred.
mainBuffer.add(jsAst.prettyPrint(node, compiler));
mainBuffer.add("$N$n");
}
// After this assignment we will produce invalid JavaScript code if we use
// the classesCollector variable.
classesCollector = 'classesCollector should not be used from now on';
emitStaticFunctions(mainBuffer);
if (!libraryBuffers.isEmpty) {
var oldClassesCollector = classesCollector;
classesCollector = r"$$";
if (compiler.enableMinification) {
mainBuffer.write(';');
}
if (!mangledFieldNames.isEmpty) {
var keys = mangledFieldNames.keys.toList();
keys.sort();
var properties = [];
for (String key in keys) {
var value = js.string('${mangledFieldNames[key]}');
properties.add(new jsAst.Property(js.string(key), value));
}
var map = new jsAst.ObjectInitializer(properties);
mainBuffer.write(
jsAst.prettyPrint(
js('init.mangledNames = #', map).toStatement(), compiler));
if (compiler.enableMinification) {
mainBuffer.write(';');
}
}
mainBuffer
..write(getReflectionDataParser())
..write('([$n');
var sortedLibraries = Elements.sortedByPosition(libraryBuffers.keys);
for (LibraryElement library in sortedLibraries) {
List<CodeBuffer> buffers = libraryBuffers[library];
var buffer = buffers[0];
var uri = library.canonicalUri;
if (uri.scheme == 'file' && compiler.sourceMapUri != null) {
// TODO(ahe): It is a hack to use compiler.sourceMapUri
// here. It should be relative to the main JavaScript
// output file.
uri = relativize(
compiler.sourceMapUri, library.canonicalUri, false);
}
if (buffer != null) {
var metadata = buildMetadataFunction(library);
mainBuffer
..write('["${library.getLibraryOrScriptName()}",$_')
..write('"${uri}",$_')
..write(metadata == null
? "" : jsAst.prettyPrint(metadata, compiler))
..write(',$_')
..write('{$n')
..addBuffer(buffer)
..write('}],$n');
}
buffer = buffers[1];
if (buffer != null) {
deferredLibraries
..write('["${library.getLibraryOrScriptName()}",$_')
..write('"${uri}",$_')
..write('[],$_')
..write('{$n')
..addBuffer(buffer)
..write('}],$n');
}
libraryBuffers[library] = const [];
}
mainBuffer.write('])$N');
emitFinishClassesInvocationIfNecessary(mainBuffer);
classesCollector = oldClassesCollector;
}
emitStaticFunctionGetters(mainBuffer);
emitRuntimeTypeSupport(mainBuffer);
emitCompileTimeConstants(mainBuffer);
// Static field initializations require the classes and compile-time
// constants to be set up.
emitStaticNonFinalFieldInitializations(mainBuffer);
emitOneShotInterceptors(mainBuffer);
emitInterceptedNames(mainBuffer);
emitGetInterceptorMethods(mainBuffer);
emitLazilyInitializedStaticFields(mainBuffer);
mainBuffer.add(nativeBuffer);
isolateProperties = isolatePropertiesName;
// The following code should not use the short-hand for the
// initialStatics.
mainBuffer.add('var ${namer.CURRENT_ISOLATE}$_=${_}null$N');
emitFinishIsolateConstructorInvocation(mainBuffer);
mainBuffer.add('var ${namer.CURRENT_ISOLATE}$_='
'${_}new ${namer.isolateName}()$N');
emitMain(mainBuffer);
emitInitFunction(mainBuffer);
compiler.assembledCode = mainBuffer.getText();
outputSourceMap(mainBuffer, compiler.assembledCode, '');
emitDeferredCode();
});
return compiler.assembledCode;
}
final Map<LibraryElement, List<CodeBuffer>> libraryBuffers =
new Map<LibraryElement, List<CodeBuffer>>();
CodeBuffer bufferForElement(Element element, CodeBuffer eagerBuffer) {
LibraryElement library = element.getLibrary();
List<CodeBuffer> buffers = libraryBuffers.putIfAbsent(
library, () => <CodeBuffer>[null, null]);
bool deferred = isDeferred(element);
int index = deferred ? 1 : 0;
CodeBuffer buffer = buffers[index];
if (buffer == null) {
buffer = buffers[index] = new CodeBuffer();
}
return buffer;
}
/**
* Returns the appropriate buffer for [constant]. If [constant] is
* itself an instance of a deferred type (or built from constants
* that are instances of deferred types) attempting to use
* [constant] before the deferred type has been loaded will not
* work, and [constant] itself must be deferred.
*/
CodeBuffer bufferForConstant(Constant constant, CodeBuffer eagerBuffer) {
var queue = new Queue()..add(constant);
while (!queue.isEmpty) {
constant = queue.removeFirst();
if (isDeferred(constant.computeType(compiler).element)) {
return deferredConstants;
}
queue.addAll(constant.getDependencies());
}
return eagerBuffer;
}
void emitDeferredCode() {
if (deferredLibraries.isEmpty && deferredConstants.isEmpty) return;
var oldClassesCollector = classesCollector;
classesCollector = r"$$";
// It does not make sense to defer constants if there are no
// deferred elements.
assert(!deferredLibraries.isEmpty);
var buffer = new CodeBuffer()
..write(buildGeneratedBy())
..write('var old${namer.CURRENT_ISOLATE}$_='
'$_${namer.CURRENT_ISOLATE}$N'
// TODO(ahe): This defines a lot of properties on the
// Isolate.prototype object. We know this will turn it into a
// slow object in V8, so instead we should do something similar
// to Isolate.$finishIsolateConstructor.
'${namer.CURRENT_ISOLATE}$_='
'$_${namer.isolateName}.prototype$N$n'
// The classesCollector object ($$).
'$classesCollector$_=$_{};$n')
..write(getReflectionDataParser())
..write('([$n')
..addBuffer(deferredLibraries)
..write('])$N');
if (!deferredClasses.isEmpty) {
buffer.write(
'$finishClassesName($classesCollector,$_${namer.CURRENT_ISOLATE},'
'$_$isolatePropertiesName)$N');
}
buffer.write(
// Reset the classesCollector ($$).
'$classesCollector$_=${_}null$N$n'
'${namer.CURRENT_ISOLATE}$_=${_}old${namer.CURRENT_ISOLATE}$N');
classesCollector = oldClassesCollector;
if (!deferredConstants.isEmpty) {
buffer.addBuffer(deferredConstants);
}
String code = buffer.getText();
compiler.outputProvider('part', 'js')
..add(code)
..close();
outputSourceMap(buffer, compiler.assembledCode, 'part');
}
String buildGeneratedBy() {
var suffix = '';
if (compiler.hasBuildId) suffix = ' version: ${compiler.buildId}';
return '// Generated by dart2js, the Dart to JavaScript compiler$suffix.\n';
}
String buildSourceMap(CodeBuffer buffer, SourceFile compiledFile) {
SourceMapBuilder sourceMapBuilder =
new SourceMapBuilder(compiler.sourceMapUri);
buffer.forEachSourceLocation(sourceMapBuilder.addMapping);
return sourceMapBuilder.build(compiledFile);
}
void outputSourceMap(CodeBuffer buffer, String code, String name) {
if (!generateSourceMap) return;
SourceFile compiledFile = new SourceFile(null, compiler.assembledCode);
String sourceMap = buildSourceMap(mainBuffer, compiledFile);
compiler.outputProvider(name, 'js.map')
..add(sourceMap)
..close();
}
bool isDeferred(Element element) {
return compiler.deferredLoadTask.isDeferred(element);
}
// TODO(ahe): Remove this when deferred loading is fully implemented.
void warnNotImplemented(Element element, String message) {
compiler.reportMessage(compiler.spanFromSpannable(element),
MessageKind.GENERIC.error({'text': message}),
api.Diagnostic.WARNING);
}
// TODO(ahe): This code should be integrated in finishClasses.
String getReflectionDataParser() {
return '''
(function (reflectionData) {
if (!init.libraries) init.libraries = [];
if (!init.mangledNames) init.mangledNames = {};
var libraries = init.libraries;
var mangledNames = init.mangledNames;
var hasOwnProperty = Object.prototype.hasOwnProperty;
var length = reflectionData.length;
for (var i = 0; i < length; i++) {
var data = reflectionData[i];
var name = data[0];
var uri = data[1];
var metadata = data[2];
var descriptor = data[3];
var classes = [];
var functions = [];
for (var property in descriptor) {
if (!hasOwnProperty.call(descriptor, property)) continue;
var element = descriptor[property];
if (property.substring(0, 1) == "@") {
property = property.substring(1);
${namer.CURRENT_ISOLATE}[property]["${namer.metadataField}"] = element;
} else if (typeof element === "function") {
${namer.CURRENT_ISOLATE}[property] = element;
functions.push(property);
} else {
var newDesc = {};
var previousProp;
for (var prop in element) {
if (!hasOwnProperty.call(element, prop)) continue;
var firstChar = prop.substring(0, 1);
if (firstChar == "+") {
mangledNames[previousProp] = prop.substring(1);
} else if (firstChar == "@" && prop != "@") {
newDesc[prop.substring(1)]["${namer.metadataField}"] ='''
'''element[prop];
} else {
newDesc[previousProp = prop] = element[prop];
}
}
$classesCollector[property] = newDesc;
classes.push(property);
}
}
libraries.push([name, uri, classes, functions, metadata]);
}
})''';
}
}
const String GENERATED_BY = """
// Generated by dart2js, the Dart to JavaScript compiler.
""";
const String HOOKS_API_USAGE = """
// The code supports the following hooks:
// dartPrint(message) - if this function is defined it is called
// instead of the Dart [print] method.
// dartMainRunner(main) - if this function is defined, the Dart [main]
// method will not be invoked directly.
// Instead, a closure that will invoke [main] is
// passed to [dartMainRunner].
""";