Revert "Move dart2js from sdk/lib/_internal/compiler to pkg/compiler"

pkg/compiler/lib/src/cps_ir/cps_ir_builder_visitor.dart

Index: pkg/compiler/lib/src/cps_ir/cps_ir_builder_visitor.dart
diff --git a/pkg/compiler/lib/src/cps_ir/cps_ir_builder_visitor.dart b/pkg/compiler/lib/src/cps_ir/cps_ir_builder_visitor.dart
deleted file mode 100644
index 162c38a7181493ed8f5709e4434af262a4bba4b7..0000000000000000000000000000000000000000
--- a/pkg/compiler/lib/src/cps_ir/cps_ir_builder_visitor.dart
+++ /dev/null
@@ -1,885 +0,0 @@
-// Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-part of dart2js.ir_builder;
-
-/**
- * This task iterates through all resolved elements and builds [ir.Node]s. The
- * nodes are stored in the [nodes] map and accessible through [hasIr] and
- * [getIr].
- *
- * The functionality of the IrNodes is added gradually, therefore elements might
- * have an IR or not, depending on the language features that are used. For
- * elements that do have an IR, the tree [ast.Node]s and the [Token]s are not
- * used in the rest of the compilation. This is ensured by setting the element's
- * cached tree to `null` and also breaking the token stream to crash future
- * attempts to parse.
- *
- * The type inferrer works on either IR nodes or tree nodes. The IR nodes are
- * then translated into the SSA form for optimizations and code generation.
- * Long-term, once the IR supports the full language, the backend can be
- * re-implemented to work directly on the IR.
- */
-class IrBuilderTask extends CompilerTask {
-  final Map<Element, ir.FunctionDefinition> nodes =
-      <Element, ir.FunctionDefinition>{};
-
-  IrBuilderTask(Compiler compiler) : super(compiler);
-
-  String get name => 'IR builder';
-
-  bool hasIr(Element element) => nodes.containsKey(element.implementation);
-
-  ir.FunctionDefinition getIr(Element element) => nodes[element.implementation];
-
-  void buildNodes({bool useNewBackend: false}) {
-    if (!irEnabled(useNewBackend: useNewBackend)) return;
-    measure(() {
-      Set<Element> resolved = compiler.enqueuer.resolution.resolvedElements;
-      resolved.forEach((AstElement element) {
-        if (canBuild(element)) {
-          TreeElements elementsMapping = element.resolvedAst.elements;
-          element = element.implementation;
-          compiler.withCurrentElement(element, () {
-            SourceFile sourceFile = elementSourceFile(element);
-            IrBuilderVisitor builder =
-                new IrBuilderVisitor(elementsMapping, compiler, sourceFile);
-            ir.FunctionDefinition function;
-            function = builder.buildFunction(element);
-
-            if (function != null) {
-              nodes[element] = function;
-              compiler.tracer.traceCompilation(element.name, null);
-              compiler.tracer.traceGraph("IR Builder", function);
-            }
-          });
-        }
-      });
-    });
-  }
-
-  bool irEnabled({bool useNewBackend: false}) {
-    // TODO(sigurdm,kmillikin): Support checked-mode checks.
-    return (useNewBackend || const bool.fromEnvironment('USE_NEW_BACKEND')) &&
-        compiler.backend is DartBackend &&
-        !compiler.enableTypeAssertions &&
-        !compiler.enableConcreteTypeInference;
-  }
-
-  bool canBuild(Element element) {
-    FunctionElement function = element.asFunctionElement();
-    // TODO(kmillikin,sigurdm): support lazy field initializers.
-    if (function == null) return false;
-
-    if (!compiler.backend.shouldOutput(function)) return false;
-
-    assert(invariant(element, !function.isNative));
-
-    // TODO(kmillikin,sigurdm): Support constructors.
-    if (function is ConstructorElement) return false;
-
-    return true;
-  }
-
-  bool get inCheckedMode {
-    bool result = false;
-    assert((result = true));
-    return result;
-  }
-
-  SourceFile elementSourceFile(Element element) {
-    if (element is FunctionElement) {
-      FunctionElement functionElement = element;
-      if (functionElement.patch != null) element = functionElement.patch;
-    }
-    return element.compilationUnit.script.file;
-  }
-}
-
-class _GetterElements {
-  ir.Primitive result;
-  ir.Primitive index;
-  ir.Primitive receiver;
-
-  _GetterElements({this.result, this.index, this.receiver}) ;
-}
-
-/**
- * A tree visitor that builds [IrNodes]. The visit methods add statements using
- * to the [builder] and return the last added statement for trees that represent
- * an expression.
- */
-class IrBuilderVisitor extends ResolvedVisitor<ir.Primitive>
-    with IrBuilderMixin<ast.Node> {
-  final Compiler compiler;
-  final SourceFile sourceFile;
-
-  // In SSA terms, join-point continuation parameters are the phis and the
-  // continuation invocation arguments are the corresponding phi inputs.  To
-  // support name introduction and renaming for source level variables, we use
-  // nested (delimited) visitors for constructing subparts of the IR that will
-  // need renaming.  Each source variable is assigned an index.
-  //
-  // Each nested visitor maintains a list of free variable uses in the body.
-  // These are implemented as a list of parameters, each with their own use
-  // list of references.  When the delimited subexpression is plugged into the
-  // surrounding context, the free occurrences can be captured or become free
-  // occurrences in the next outer delimited subexpression.
-  //
-  // Each nested visitor maintains a list that maps indexes of variables
-  // assigned in the delimited subexpression to their reaching definition ---
-  // that is, the definition in effect at the hole in 'current'.  These are
-  // used to determine if a join-point continuation needs to be passed
-  // arguments, and what the arguments are.
-
-  /// Construct a top-level visitor.
-  IrBuilderVisitor(TreeElements elements, this.compiler, this.sourceFile)
-      : super(elements);
-
-  /**
-   * Builds the [ir.FunctionDefinition] for a function element. In case the
-   * function uses features that cannot be expressed in the IR, this function
-   * returns `null`.
-   */
-  ir.FunctionDefinition buildFunction(FunctionElement functionElement) {
-    return nullIfGiveup(() => buildFunctionInternal(functionElement));
-  }
-
-  ir.FunctionDefinition buildFunctionInternal(FunctionElement element) {
-    assert(invariant(element, element.isImplementation));
-    ast.FunctionExpression function = element.node;
-    assert(function != null);
-    assert(!function.modifiers.isExternal);
-    assert(elements[function] != null);
-
-    DetectClosureVariables closureLocals = new DetectClosureVariables(elements);
-    closureLocals.visit(function);
-
-    return withBuilder(
-        new IrBuilder(compiler.backend.constantSystem,
-                      element, closureLocals.usedFromClosure),
-        () {
-      FunctionSignature signature = element.functionSignature;
-      signature.orderedForEachParameter((ParameterElement parameterElement) {
-        irBuilder.createParameter(parameterElement);
-      });
-
-      List<ConstantExpression> defaults = new List<ConstantExpression>();
-      signature.orderedOptionalParameters.forEach((ParameterElement element) {
-        defaults.add(getConstantForVariable(element));
-      });
-
-      visit(function.body);
-      return irBuilder.buildFunctionDefinition(element, defaults);
-    });
-  }
-
-  ir.Primitive visit(ast.Node node) => node.accept(this);
-
-  // ==== Statements ====
-  visitBlock(ast.Block node) {
-    irBuilder.buildBlock(node.statements.nodes, build);
-  }
-
-  ir.Primitive visitBreakStatement(ast.BreakStatement node) {
-    if (!irBuilder.buildBreak(elements.getTargetOf(node))) {
-      compiler.internalError(node, "'break' target not found");
-    }
-    return null;
-  }
-
-  ir.Primitive visitContinueStatement(ast.ContinueStatement node) {
-    if (!irBuilder.buildContinue(elements.getTargetOf(node))) {
-      compiler.internalError(node, "'continue' target not found");
-    }
-    return null;
-  }
-
-  // Build(EmptyStatement, C) = C
-  ir.Primitive visitEmptyStatement(ast.EmptyStatement node) {
-    assert(irBuilder.isOpen);
-    return null;
-  }
-
-  // Build(ExpressionStatement(e), C) = C'
-  //   where (C', _) = Build(e, C)
-  ir.Primitive visitExpressionStatement(ast.ExpressionStatement node) {
-    assert(irBuilder.isOpen);
-    visit(node.expression);
-    return null;
-  }
-
-  visitFor(ast.For node) {
-    // TODO(kmillikin,sigurdm): Handle closure variables declared in a for-loop.
-    if (node.initializer is ast.VariableDefinitions) {
-      ast.VariableDefinitions definitions = node.initializer;
-      for (ast.Node definition in definitions.definitions.nodes) {
-        Element element = elements[definition];
-        if (irBuilder.isClosureVariable(element)) {
-          return giveup(definition, 'Closure variable in for loop initializer');
-        }
-      }
-    }
-
-    JumpTarget target = elements.getTargetDefinition(node);
-    irBuilder.buildFor(
-        buildInitializer: subbuild(node.initializer),
-        buildCondition: subbuild(node.condition),
-        buildBody: subbuild(node.body),
-        buildUpdate: subbuildSequence(node.update),
-        target: target);
-  }
-
-  visitIf(ast.If node) {
-    irBuilder.buildIf(
-        build(node.condition),
-        subbuild(node.thenPart),
-        subbuild(node.elsePart));
-  }
-
-  ir.Primitive visitLabeledStatement(ast.LabeledStatement node) {
-    ast.Statement body = node.statement;
-    return body is ast.Loop
-        ? visit(body)
-        : giveup(node, 'labeled statement');
-  }
-
-  visitWhile(ast.While node) {
-    irBuilder.buildWhile(
-        buildCondition: subbuild(node.condition),
-        buildBody: subbuild(node.body),
-        target: elements.getTargetDefinition(node));
-  }
-
-  visitForIn(ast.ForIn node) {
-    // [node.declaredIdentifier] can be either an [ast.VariableDefinitions]
-    // (defining a new local variable) or a send designating some existing
-    // variable.
-    ast.Node identifier = node.declaredIdentifier;
-    ast.VariableDefinitions variableDeclaration =
-        identifier.asVariableDefinitions();
-    Element variableElement = elements.getForInVariable(node);
-    Selector selector = elements.getSelector(identifier);
-
-    irBuilder.buildForIn(
-        buildExpression: subbuild(node.expression),
-        buildVariableDeclaration: subbuild(variableDeclaration),
-        variableElement: variableElement,
-        variableSelector: selector,
-        buildBody: subbuild(node.body),
-        target: elements.getTargetDefinition(node));
-  }
-
-  ir.Primitive visitVariableDefinitions(ast.VariableDefinitions node) {
-    assert(irBuilder.isOpen);
-    if (node.modifiers.isConst) {
-      for (ast.SendSet definition in node.definitions.nodes) {
-        assert(!definition.arguments.isEmpty);
-        assert(definition.arguments.tail.isEmpty);
-        VariableElement element = elements[definition];
-        ConstantExpression value = getConstantForVariable(element);
-        irBuilder.declareLocalConstant(element, value);
-      }
-    } else {
-      for (ast.Node definition in node.definitions.nodes) {
-        Element element = elements[definition];
-        ir.Primitive initialValue;
-        // Definitions are either SendSets if there is an initializer, or
-        // Identifiers if there is no initializer.
-        if (definition is ast.SendSet) {
-          assert(!definition.arguments.isEmpty);
-          assert(definition.arguments.tail.isEmpty);
-          initialValue = visit(definition.arguments.head);
-        } else {
-          assert(definition is ast.Identifier);
-        }
-        irBuilder.declareLocalVariable(element, initialValue: initialValue);
-      }
-    }
-    return null;
-  }
-
-  // Build(Return(e), C) = C'[InvokeContinuation(return, x)]
-  //   where (C', x) = Build(e, C)
-  //
-  // Return without a subexpression is translated as if it were return null.
-  ir.Primitive visitReturn(ast.Return node) {
-    assert(irBuilder.isOpen);
-    assert(invariant(node, node.beginToken.value != 'native'));
-    irBuilder.buildReturn(build(node.expression));
-    return null;
-  }
-
-  // ==== Expressions ====
-  ir.Primitive visitConditional(ast.Conditional node) {
-    return irBuilder.buildConditional(
-        build(node.condition),
-        subbuild(node.thenExpression),
-        subbuild(node.elseExpression));
-  }
-
-  // For all simple literals:
-  // Build(Literal(c), C) = C[let val x = Constant(c) in [], x]
-  ir.Primitive visitLiteralBool(ast.LiteralBool node) {
-    assert(irBuilder.isOpen);
-    return translateConstant(node);
-  }
-
-  ir.Primitive visitLiteralDouble(ast.LiteralDouble node) {
-    assert(irBuilder.isOpen);
-    return translateConstant(node);
-  }
-
-  ir.Primitive visitLiteralInt(ast.LiteralInt node) {
-    assert(irBuilder.isOpen);
-    return translateConstant(node);
-  }
-
-  ir.Primitive visitLiteralNull(ast.LiteralNull node) {
-    assert(irBuilder.isOpen);
-    return translateConstant(node);
-  }
-
-  ir.Primitive visitLiteralString(ast.LiteralString node) {
-    assert(irBuilder.isOpen);
-    return translateConstant(node);
-  }
-
-  ConstantExpression getConstantForNode(ast.Node node) {
-    ConstantExpression constant =
-        compiler.backend.constantCompilerTask.compileNode(node, elements);
-    assert(invariant(node, constant != null,
-        message: 'No constant computed for $node'));
-    return constant;
-  }
-
-  ConstantExpression getConstantForVariable(VariableElement element) {
-    ConstantExpression constant =
-        compiler.backend.constants.getConstantForVariable(element);
-    assert(invariant(element, constant != null,
-            message: 'No constant computed for $element'));
-    return constant;
-  }
-
-  ir.Primitive visitLiteralList(ast.LiteralList node) {
-    if (node.isConst) {
-      return translateConstant(node);
-    }
-    List<ir.Primitive> values = node.elements.nodes.mapToList(visit);
-    InterfaceType type = elements.getType(node);
-    return irBuilder.buildListLiteral(type, values);
-  }
-
-  ir.Primitive visitLiteralMap(ast.LiteralMap node) {
-    if (node.isConst) {
-      return translateConstant(node);
-    }
-    InterfaceType type = elements.getType(node);
-    return irBuilder.buildMapLiteral(
-        type,
-        node.entries.nodes.map((e) => e.key),
-        node.entries.nodes.map((e) => e.value),
-        build);
-  }
-
-  ir.Primitive visitLiteralSymbol(ast.LiteralSymbol node) {
-    assert(irBuilder.isOpen);
-    return translateConstant(node);
-  }
-
-  ir.Primitive visitIdentifier(ast.Identifier node) {
-    // "this" is the only identifier that should be met by the visitor.
-    assert(node.isThis());
-    return irBuilder.buildThis();
-  }
-
-  ir.Primitive visitParenthesizedExpression(
-      ast.ParenthesizedExpression node) {
-    assert(irBuilder.isOpen);
-    return visit(node.expression);
-  }
-
-  // Stores the result of visiting a CascadeReceiver, so we can return it from
-  // its enclosing Cascade.
-  ir.Primitive _currentCascadeReceiver;
-
-  ir.Primitive visitCascadeReceiver(ast.CascadeReceiver node) {
-    assert(irBuilder.isOpen);
-    return _currentCascadeReceiver = visit(node.expression);
-  }
-
-  ir.Primitive visitCascade(ast.Cascade node) {
-    assert(irBuilder.isOpen);
-    var oldCascadeReceiver = _currentCascadeReceiver;
-    // Throw away the result of visiting the expression.
-    // Instead we return the result of visiting the CascadeReceiver.
-    this.visit(node.expression);
-    ir.Primitive receiver = _currentCascadeReceiver;
-    _currentCascadeReceiver = oldCascadeReceiver;
-    return receiver;
-  }
-
-  // ==== Sends ====
-  ir.Primitive visitAssert(ast.Send node) {
-    assert(irBuilder.isOpen);
-    return giveup(node, 'Assert');
-  }
-
-  ir.Primitive visitNamedArgument(ast.NamedArgument node) {
-    assert(irBuilder.isOpen);
-    return visit(node.expression);
-  }
-
-  ir.Primitive translateClosureCall(ir.Primitive receiver,
-                                    Selector closureSelector,
-                                    ast.NodeList arguments) {
-    Selector namedCallSelector = new Selector(closureSelector.kind,
-                     "call",
-                     closureSelector.library,
-                     closureSelector.argumentCount,
-                     closureSelector.namedArguments);
-    List<ir.Primitive> args = arguments.nodes.mapToList(visit, growable:false);
-    return irBuilder.buildDynamicInvocation(receiver, namedCallSelector, args);
-  }
-
-  ir.Primitive visitClosureSend(ast.Send node) {
-    assert(irBuilder.isOpen);
-    Element element = elements[node];
-    ir.Primitive closureTarget;
-    if (element == null) {
-      closureTarget = visit(node.selector);
-    } else if (irBuilder.isClosureVariable(element)) {
-      LocalElement local = element;
-      closureTarget = new ir.GetClosureVariable(local);
-      irBuilder.add(new ir.LetPrim(closureTarget));
-    } else {
-      assert(Elements.isLocal(element));
-      closureTarget = irBuilder.environment.lookup(element);
-    }
-    Selector closureSelector = elements.getSelector(node);
-    return translateClosureCall(closureTarget, closureSelector,
-        node.argumentsNode);
-  }
-
-  /// If [node] is null, returns this.
-  /// If [node] is super, returns null (for special handling)
-  /// Otherwise visits [node] and returns the result.
-  ir.Primitive visitReceiver(ast.Expression node) {
-    if (node == null) return irBuilder.buildThis();
-    if (node.isSuper()) return null;
-    return visit(node);
-  }
-
-  /// Returns `true` if [node] is a super call.
-  // TODO(johnniwinther): Remove the need for this.
-  bool isSuperCall(ast.Send node) {
-    return node != null && node.receiver != null && node.receiver.isSuper();
-  }
-
-  ir.Primitive visitDynamicSend(ast.Send node) {
-    assert(irBuilder.isOpen);
-    Selector selector = elements.getSelector(node);
-    ir.Primitive receiver = visitReceiver(node.receiver);
-    List<ir.Primitive> arguments = new List<ir.Primitive>();
-    for (ast.Node n in node.arguments) {
-      arguments.add(visit(n));
-    }
-    return irBuilder.buildDynamicInvocation(receiver, selector, arguments);
-  }
-
-  _GetterElements translateGetter(ast.Send node, Selector selector) {
-    Element element = elements[node];
-    ir.Primitive result;
-    ir.Primitive receiver;
-    ir.Primitive index;
-
-    if (element != null && element.isConst) {
-      // Reference to constant local, top-level or static field
-      result = translateConstant(node);
-    } else if (Elements.isLocal(element)) {
-      // Reference to local variable
-      result = irBuilder.buildLocalGet(element);
-    } else if (element == null ||
-               Elements.isInstanceField(element) ||
-               Elements.isInstanceMethod(element) ||
-               selector.isIndex ||
-               // TODO(johnniwinther): clean up semantics of resolution.
-               node.isSuperCall) {
-      // Dynamic dispatch to a getter. Sometimes resolution will suggest a
-      // target element, but in these cases we must still emit a dynamic
-      // dispatch. The target element may be an instance method in case we are
-      // converting a method to a function object.
-
-      receiver = visitReceiver(node.receiver);
-      List<ir.Primitive> arguments = new List<ir.Primitive>();
-      if (selector.isIndex) {
-        index = visit(node.arguments.head);
-        arguments.add(index);
-      }
-
-      assert(selector.kind == SelectorKind.GETTER ||
-             selector.kind == SelectorKind.INDEX);
-      if (isSuperCall(node)) {
-        result = irBuilder.buildSuperInvocation(selector, arguments);
-      } else {
-        result =
-            irBuilder.buildDynamicInvocation(receiver, selector, arguments);
-      }
-    } else if (element.isField || element.isGetter || element.isErroneous ||
-               element.isSetter) {
-      // TODO(johnniwinther): Change handling of setter selectors.
-      // Access to a static field or getter (non-static case handled above).
-      // Even if there is only a setter, we compile as if it was a getter,
-      // so the vm can fail at runtime.
-      assert(selector.kind == SelectorKind.GETTER ||
-             selector.kind == SelectorKind.SETTER);
-      result = irBuilder.buildStaticGet(element, selector);
-    } else if (Elements.isStaticOrTopLevelFunction(element)) {
-      // Convert a top-level or static function to a function object.
-      result = translateConstant(node);
-    } else {
-      throw "Unexpected SendSet getter: $node, $element";
-    }
-    return new _GetterElements(
-        result: result,index: index, receiver: receiver);
-  }
-
-  ir.Primitive visitGetterSend(ast.Send node) {
-    assert(irBuilder.isOpen);
-    return translateGetter(node, elements.getSelector(node)).result;
-
-  }
-
-  ir.Primitive translateLogicalOperator(ast.Operator op,
-                                        ast.Expression left,
-                                        ast.Expression right) {
-    ir.Primitive leftValue = visit(left);
-
-    ir.Primitive buildRightValue(IrBuilder rightBuilder) {
-      return withBuilder(rightBuilder, () => visit(right));
-    }
-
-    return irBuilder.buildLogicalOperator(
-        leftValue, buildRightValue, isLazyOr: op.source == '||');
-  }
-
-  ir.Primitive visitOperatorSend(ast.Send node) {
-    assert(irBuilder.isOpen);
-    ast.Operator op = node.selector;
-    if (isUserDefinableOperator(op.source)) {
-      return visitDynamicSend(node);
-    }
-    if (op.source == '&&' || op.source == '||') {
-      assert(node.receiver != null);
-      assert(!node.arguments.isEmpty);
-      assert(node.arguments.tail.isEmpty);
-      return translateLogicalOperator(op, node.receiver, node.arguments.head);
-    }
-    if (op.source == "!") {
-      assert(node.receiver != null);
-      assert(node.arguments.isEmpty);
-      return irBuilder.buildNegation(visit(node.receiver));
-    }
-    if (op.source == "!=") {
-      assert(node.receiver != null);
-      assert(!node.arguments.isEmpty);
-      assert(node.arguments.tail.isEmpty);
-      return irBuilder.buildNegation(visitDynamicSend(node));
-    }
-    assert(invariant(node, op.source == "is" || op.source == "as",
-           message: "unexpected operator $op"));
-    DartType type = elements.getType(node.typeAnnotationFromIsCheckOrCast);
-    ir.Primitive receiver = visit(node.receiver);
-    return irBuilder.buildTypeOperator(
-        receiver, type,
-        isTypeTest: op.source == "is",
-        isNotCheck: node.isIsNotCheck);
-  }
-
-  // Build(StaticSend(f, arguments), C) = C[C'[InvokeStatic(f, xs)]]
-  //   where (C', xs) = arguments.fold(Build, C)
-  ir.Primitive visitStaticSend(ast.Send node) {
-    assert(irBuilder.isOpen);
-    Element element = elements[node];
-    assert(!element.isConstructor);
-    // TODO(lry): support foreign functions.
-    if (element.isForeign(compiler.backend)) {
-      return giveup(node, 'StaticSend: foreign');
-    }
-
-    Selector selector = elements.getSelector(node);
-
-    // TODO(lry): support default arguments, need support for locals.
-    List<ir.Definition> arguments = node.arguments.mapToList(visit,
-                                                             growable:false);
-    return irBuilder.buildStaticInvocation(element, selector, arguments);
-  }
-
-  ir.Primitive visitSuperSend(ast.Send node) {
-    assert(irBuilder.isOpen);
-    if (node.isPropertyAccess) {
-      return visitGetterSend(node);
-    } else {
-      Selector selector = elements.getSelector(node);
-      List<ir.Primitive> arguments = new List<ir.Primitive>();
-      for (ast.Node n in node.arguments) {
-        arguments.add(visit(n));
-      }
-      return irBuilder.buildSuperInvocation(selector, arguments);
-    }
-  }
-
-  visitTypePrefixSend(ast.Send node) {
-    compiler.internalError(node, "visitTypePrefixSend should not be called.");
-  }
-
-  ir.Primitive visitTypeLiteralSend(ast.Send node) {
-    assert(irBuilder.isOpen);
-    // If the user is trying to invoke the type literal or variable,
-    // it must be treated as a function call.
-    if (node.argumentsNode != null) {
-      // TODO(sigurdm): Handle this to match proposed semantics of issue #19725.
-      return giveup(node, 'Type literal invoked as function');
-    }
-
-    DartType type = elements.getTypeLiteralType(node);
-    if (type is TypeVariableType) {
-      ir.Primitive prim = new ir.ReifyTypeVar(type.element);
-      irBuilder.add(new ir.LetPrim(prim));
-      return prim;
-    } else {
-      return translateConstant(node);
-    }
-  }
-
-  ir.Primitive visitSendSet(ast.SendSet node) {
-    assert(irBuilder.isOpen);
-    Element element = elements[node];
-    ast.Operator op = node.assignmentOperator;
-    // For complex operators, this is the result of getting (before assigning)
-    ir.Primitive originalValue;
-    // For []+= style operators, this saves the index.
-    ir.Primitive index;
-    ir.Primitive receiver;
-    // This is what gets assigned.
-    ir.Primitive valueToStore;
-    Selector selector = elements.getSelector(node);
-    Selector operatorSelector =
-        elements.getOperatorSelectorInComplexSendSet(node);
-    Selector getterSelector =
-        elements.getGetterSelectorInComplexSendSet(node);
-    assert(
-        // Indexing send-sets have an argument for the index.
-        (selector.isIndexSet ? 1 : 0) +
-        // Non-increment send-sets have one more argument.
-        (ast.Operator.INCREMENT_OPERATORS.contains(op.source) ? 0 : 1)
-            == node.argumentCount());
-
-    ast.Node getAssignArgument() {
-      assert(invariant(node, !node.arguments.isEmpty,
-                       message: "argument expected"));
-      return selector.isIndexSet
-          ? node.arguments.tail.head
-          : node.arguments.head;
-    }
-
-    // Get the value into valueToStore
-    if (op.source == "=") {
-      if (selector.isIndexSet) {
-        receiver = visitReceiver(node.receiver);
-        index = visit(node.arguments.head);
-      } else if (element == null || Elements.isInstanceField(element)) {
-        receiver = visitReceiver(node.receiver);
-      }
-      valueToStore = visit(getAssignArgument());
-    } else {
-      // Get the original value into getter
-      assert(ast.Operator.COMPLEX_OPERATORS.contains(op.source));
-
-      _GetterElements getterResult = translateGetter(node, getterSelector);
-      index = getterResult.index;
-      receiver = getterResult.receiver;
-      originalValue = getterResult.result;
-
-      // Do the modification of the value in getter.
-      ir.Primitive arg;
-      if (ast.Operator.INCREMENT_OPERATORS.contains(op.source)) {
-        arg = irBuilder.buildIntegerLiteral(1);
-      } else {
-        arg = visit(getAssignArgument());
-      }
-      valueToStore = new ir.Parameter(null);
-      ir.Continuation k = new ir.Continuation([valueToStore]);
-      ir.Expression invoke =
-          new ir.InvokeMethod(originalValue, operatorSelector, k, [arg]);
-      irBuilder.add(new ir.LetCont(k, invoke));
-    }
-
-    if (Elements.isLocal(element)) {
-      irBuilder.buildLocalSet(element, valueToStore);
-    } else if ((!node.isSuperCall && Elements.isErroneousElement(element)) ||
-                Elements.isStaticOrTopLevel(element)) {
-      irBuilder.buildStaticSet(
-          element, elements.getSelector(node), valueToStore);
-    } else {
-      // Setter or index-setter invocation
-      Selector selector = elements.getSelector(node);
-      assert(selector.kind == SelectorKind.SETTER ||
-          selector.kind == SelectorKind.INDEX);
-      if (selector.isIndexSet) {
-        if (isSuperCall(node)) {
-          irBuilder.buildSuperIndexSet(index, valueToStore);
-        } else {
-          irBuilder.buildDynamicIndexSet(receiver, index, valueToStore);
-        }
-      } else {
-        if (isSuperCall(node)) {
-          irBuilder.buildSuperSet(selector, valueToStore);
-        } else {
-          irBuilder.buildDynamicSet(receiver, selector, valueToStore);
-        }
-      }
-    }
-
-    if (node.isPostfix) {
-      assert(originalValue != null);
-      return originalValue;
-    } else {
-      return valueToStore;
-    }
-  }
-
-  ir.Primitive visitNewExpression(ast.NewExpression node) {
-    if (node.isConst) {
-      return translateConstant(node);
-    }
-    FunctionElement element = elements[node.send];
-    Selector selector = elements.getSelector(node.send);
-    DartType type = elements.getType(node);
-    ast.Node selectorNode = node.send.selector;
-    List<ir.Definition> arguments =
-        node.send.arguments.mapToList(visit, growable:false);
-    return irBuilder.buildConstructorInvocation(
-        element, selector, type, arguments);
-  }
-
-  ir.Primitive visitStringJuxtaposition(ast.StringJuxtaposition node) {
-    assert(irBuilder.isOpen);
-    ir.Primitive first = visit(node.first);
-    ir.Primitive second = visit(node.second);
-    return irBuilder.buildStringConcatenation([first, second]);
-  }
-
-  ir.Primitive visitStringInterpolation(ast.StringInterpolation node) {
-    assert(irBuilder.isOpen);
-    List<ir.Primitive> arguments = [];
-    arguments.add(visitLiteralString(node.string));
-    var it = node.parts.iterator;
-    while (it.moveNext()) {
-      ast.StringInterpolationPart part = it.current;
-      arguments.add(visit(part.expression));
-      arguments.add(visitLiteralString(part.string));
-    }
-    return irBuilder.buildStringConcatenation(arguments);
-  }
-
-  ir.Primitive translateConstant(ast.Node node, [ConstantExpression constant]) {
-    assert(irBuilder.isOpen);
-    if (constant == null) {
-      constant = getConstantForNode(node);
-    }
-    return irBuilder.buildConstantLiteral(constant);
-  }
-
-  ir.FunctionDefinition makeSubFunction(ast.FunctionExpression node) {
-    // TODO(johnniwinther): Share the visitor.
-    return new IrBuilderVisitor(elements, compiler, sourceFile)
-           .buildFunctionInternal(elements[node]);
-  }
-
-  ir.Primitive visitFunctionExpression(ast.FunctionExpression node) {
-    FunctionElement element = elements[node];
-    ir.FunctionDefinition inner = makeSubFunction(node);
-    ir.CreateFunction prim = new ir.CreateFunction(inner);
-    irBuilder.add(new ir.LetPrim(prim));
-    return prim;
-  }
-
-  ir.Primitive visitFunctionDeclaration(ast.FunctionDeclaration node) {
-    LocalFunctionElement element = elements[node.function];
-    ir.FunctionDefinition inner = makeSubFunction(node.function);
-    if (irBuilder.isClosureVariable(element)) {
-      irBuilder.add(new ir.DeclareFunction(element, inner));
-    } else {
-      ir.CreateFunction prim = new ir.CreateFunction(inner);
-      irBuilder.add(new ir.LetPrim(prim));
-      irBuilder.environment.extend(element, prim);
-      prim.useElementAsHint(element);
-    }
-    return null;
-  }
-
-  static final String ABORT_IRNODE_BUILDER = "IrNode builder aborted";
-
-  dynamic giveup(ast.Node node, [String reason]) {
-    throw ABORT_IRNODE_BUILDER;
-  }
-
-  ir.FunctionDefinition nullIfGiveup(ir.FunctionDefinition action()) {
-    try {
-      return action();
-    } catch(e, tr) {
-      if (e == ABORT_IRNODE_BUILDER) {
-        return null;
-      }
-      rethrow;
-    }
-  }
-
-  void internalError(String reason, {ast.Node node}) {
-    giveup(node);
-  }
-}
-
-/// Classifies local variables and local functions as 'closure variables'.
-/// A closure variable is one that is accessed from an inner function nested
-/// one or more levels inside the one that declares it.
-class DetectClosureVariables extends ast.Visitor {
-  final TreeElements elements;
-  DetectClosureVariables(this.elements);
-
-  FunctionElement currentFunction;
-  Set<Local> usedFromClosure = new Set<Local>();
-  Set<FunctionElement> recursiveFunctions = new Set<FunctionElement>();
-
-  bool isClosureVariable(Entity entity) => usedFromClosure.contains(entity);
-
-  void markAsClosureVariable(Local local) {
-    usedFromClosure.add(local);
-  }
-
-  visit(ast.Node node) => node.accept(this);
-
-  visitNode(ast.Node node) {
-    node.visitChildren(this);
-  }
-
-  visitSend(ast.Send node) {
-    Element element = elements[node];
-    if (Elements.isLocal(element) &&
-        !element.isConst &&
-        element.enclosingElement != currentFunction) {
-      LocalElement local = element;
-      markAsClosureVariable(local);
-    }
-    node.visitChildren(this);
-  }
-
-  visitFunctionExpression(ast.FunctionExpression node) {
-    FunctionElement oldFunction = currentFunction;
-    currentFunction = elements[node];
-    visit(node.body);
-    currentFunction = oldFunction;
-  }
-}