Handle for-loop with simple break in compile_from_dill_test

R=sigmund@google.com

Review-Url: https://codereview.chromium.org/2950303002 .

pkg/compiler/lib/src/elements/jumps.dart

@@ -12,7 +12,8 @@ abstract class LabelDefinition<T> extends Entity {
   String get labelName;
   JumpTarget<T> get target;
 
-  bool get isTarget;
+  bool get isTarget => isBreakTarget || isContinueTarget;
+
   bool get isBreakTarget;
   bool get isContinueTarget;
 }
@@ -20,11 +21,14 @@ abstract class LabelDefinition<T> extends Entity {
 /// A jump target is the reference point of a statement or switch-case,
 /// either by label or as the default target of a break or continue.
 abstract class JumpTarget<T> extends Local {
+  String get name => 'target';
+
+  bool get isTarget => isBreakTarget || isContinueTarget;
+
   T get statement;
   int get nestingLevel;
   List<LabelDefinition<T>> get labels;
 
-  bool get isTarget;
   bool get isBreakTarget;
   bool get isContinueTarget;
   bool get isSwitch;

pkg/compiler/lib/src/elements/modelx.dart

@@ -3337,7 +3337,7 @@ class UnnamedMixinApplicationElementX extends MixinApplicationElementX {
   bool get isAbstract => true;
 }
 
-class LabelDefinitionX implements LabelDefinition<Node> {
+class LabelDefinitionX extends LabelDefinition<Node> {
   final Label label;
   final String labelName;
   final JumpTargetX target;
@@ -3362,12 +3362,10 @@ class LabelDefinitionX implements LabelDefinition<Node> {
     target.isContinueTarget = true;
   }
 
-  bool get isTarget => isBreakTarget || isContinueTarget;
-
   String toString() => 'Label:${name}';
 }
 
-class JumpTargetX implements JumpTarget<Node> {
+class JumpTargetX extends JumpTarget<Node> {
   final ExecutableElement executableContext;
   final Node statement;
   final int nestingLevel;
@@ -3382,10 +3380,6 @@ class JumpTargetX implements JumpTarget<Node> {
   @override
   MemberElement get memberContext => executableContext.memberContext;
 
-  String get name => "target";
-
-  bool get isTarget => isBreakTarget || isContinueTarget;
-
   LabelDefinition<Node> addLabel(Label label, String labelName,
       {bool isBreakTarget: false}) {
     LabelDefinitionX result = new LabelDefinitionX(label, labelName, this);

pkg/compiler/lib/src/kernel/kernel_backend_strategy.dart

@@ -8,6 +8,7 @@ import 'package:kernel/ast.dart' as ir;
 
 import '../backend_strategy.dart';
 import '../closure.dart';
+import '../common.dart';
 import '../common/codegen.dart' show CodegenRegistry, CodegenWorkItem;
 import '../common/tasks.dart';
 import '../compiler.dart';
@@ -279,9 +280,25 @@ class GlobalLocalsMap {
 class KernelToLocalsMapImpl implements KernelToLocalsMap {
   final List<MemberEntity> _members = <MemberEntity>[];
   Map<ir.VariableDeclaration, KLocal> _map = <ir.VariableDeclaration, KLocal>{};
+  Map<ir.LabeledStatement, KJumpTarget> _jumpTargetMap;
 
   MemberEntity get currentMember => _members.last;
 
+  // TODO(johnniwinther): Compute this eagerly from the root of the member.
+  void _ensureJumpMap(ir.TreeNode node) {
+    if (_jumpTargetMap == null) {
+      JumpVisitor visitor = new JumpVisitor(currentMember);
+
+      // Find the root node for the current member.
+      while (node is! ir.Member) {
+        node = node.parent;
+      }
+
+      node.accept(visitor);
+      _jumpTargetMap = visitor.jumpTargetMap;
+    }
+  }
+
   KernelToLocalsMapImpl(MemberEntity member) {
     _members.add(member);
   }
@@ -299,54 +316,63 @@ class KernelToLocalsMapImpl implements KernelToLocalsMap {
 
   @override
   JumpTarget getJumpTargetForBreak(ir.BreakStatement node) {
-    throw new UnimplementedError('KernelToLocalsMapImpl.getJumpTargetForBreak');
+    _ensureJumpMap(node.target);
+    JumpTarget target = _jumpTargetMap[node.target];
+    assert(target != null, failedAt(currentMember, 'No target for $node.'));
+    return target;
   }
 
   @override
   JumpTarget getJumpTargetForContinueSwitch(ir.ContinueSwitchStatement node) {
+    _ensureJumpMap(node.target);
     throw new UnimplementedError(
         'KernelToLocalsMapImpl.getJumpTargetForContinueSwitch');
   }
 
   @override
   JumpTarget getJumpTargetForSwitchCase(ir.SwitchCase node) {
+    _ensureJumpMap(node);
     throw new UnimplementedError(
         'KernelToLocalsMapImpl.getJumpTargetForSwitchCase');
   }
 
   @override
   JumpTarget getJumpTargetForDo(ir.DoStatement node) {
-    // TODO(redemption): Support do statement as jump target.
-    return null;
+    _ensureJumpMap(node);
+    return _jumpTargetMap[node.parent];
   }
 
   @override
   JumpTarget getJumpTargetForLabel(ir.LabeledStatement node) {
-    throw new UnimplementedError('KernelToLocalsMapImpl.getJumpTargetForLabel');
+    _ensureJumpMap(node);
+    JumpTarget target = _jumpTargetMap[node];
+    assert(target != null, failedAt(currentMember, 'No target for $node.'));
+    return target;
   }
 
   @override
   JumpTarget getJumpTargetForSwitch(ir.SwitchStatement node) {
+    _ensureJumpMap(node);
     throw new UnimplementedError(
         'KernelToLocalsMapImpl.getJumpTargetForSwitch');
   }
 
   @override
   JumpTarget getJumpTargetForFor(ir.ForStatement node) {
-    // TODO(redemption): Support for statement as jump target.
-    return null;
+    _ensureJumpMap(node);
+    return _jumpTargetMap[node.parent];
   }
 
   @override
   JumpTarget getJumpTargetForForIn(ir.ForInStatement node) {
-    // TODO(redemption): Support for-in statement as jump target.
-    return null;
+    _ensureJumpMap(node);
+    return _jumpTargetMap[node.parent];
   }
 
   @override
   JumpTarget getJumpTargetForWhile(ir.WhileStatement node) {
-    // TODO(redemption): Support while statement as jump target.
-    return null;
+    _ensureJumpMap(node);
+    return _jumpTargetMap[node.parent];
   }
 
   @override
@@ -363,6 +389,60 @@ class KernelToLocalsMapImpl implements KernelToLocalsMap {
   }
 }
 
+class JumpVisitor extends ir.Visitor {
+  final MemberEntity member;
+  final Map<ir.LabeledStatement, KJumpTarget> jumpTargetMap =
+      <ir.LabeledStatement, KJumpTarget>{};
+
+  JumpVisitor(this.member);
+
+  KJumpTarget _getJumpTarget(ir.LabeledStatement node) {
+    return jumpTargetMap.putIfAbsent(node, () {
+      return new KJumpTarget(member, jumpTargetMap.length);
+    });
+  }
+
+  @override
+  defaultNode(ir.Node node) => node.visitChildren(this);
+
+  @override
+  visitBreakStatement(ir.BreakStatement node) {
+    KJumpTarget target = _getJumpTarget(node.target);
+    target.isBreakTarget = true;
+    super.visitBreakStatement(node);
+  }
+}
+
+class KJumpTarget extends JumpTarget<ir.Node> {
+  final MemberEntity memberContext;
+  final int nestingLevel;
+
+  KJumpTarget(this.memberContext, this.nestingLevel);
+
+  bool isBreakTarget = false;
+  bool isContinueTarget = false;
+  bool isSwitch = false;
+
+  @override
+  Entity get executableContext => memberContext;
+
+  @override
+  LabelDefinition<ir.Node> addLabel(ir.Node label, String labelName,
+      {bool isBreakTarget: false}) {
+    throw new UnimplementedError('KJumpTarget.addLabel');
+  }
+
+  @override
+  List<LabelDefinition<ir.Node>> get labels {
+    return const <LabelDefinition<ir.Node>>[];
+  }
+
+  @override
+  ir.Node get statement {
+    throw new UnimplementedError('KJumpTarget.statement');
+  }
+}
+
 class KLocal implements Local {
   final String name;
   final MemberEntity memberContext;

tests/compiler/dart2js/kernel/compile_from_dill_test.dart

@@ -48,6 +48,10 @@ main() {
   new Class('');
   Class.staticField;
   var x = null;
+  for (int i = 0; i < 10; i++) {
+    x = i;
+    if (i == 5) break;
+  }
   return x;
 }
 '''