Implement complex switch statement (switch with continue).

pkg/compiler/lib/src/ssa/jump_handler.dart

 // Copyright (c) 2016, 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.
 
 import '../common.dart';
 import '../elements/elements.dart';
 import '../tree/tree.dart' as ast;
 
 import 'builder.dart';
 import 'graph_builder.dart';
@@ skipping 132 matching lines @@
     for (LabelDefinition element in target.labels) {
       result ??= <LabelDefinition>[];
       result.add(element);
     }
     return result ?? const <LabelDefinition>[];
   }
 }
 
 /// Special [JumpHandler] implementation used to handle continue statements
 /// targeting switch cases.
-class SwitchCaseJumpHandler extends TargetJumpHandler {
+abstract class SwitchCaseJumpHandler extends TargetJumpHandler {
   /// Map from switch case targets to indices used to encode the flow of the
   /// switch case loop.
   final Map<JumpTarget, int> targetIndexMap = new Map<JumpTarget, int>();
 
   SwitchCaseJumpHandler(
-      GraphBuilder builder, JumpTarget target, ast.SwitchStatement node)
-      : super(builder, target) {
-    // The switch case indices must match those computed in
-    // [SsaFromAstMixin.buildSwitchCaseConstants].
-    // Switch indices are 1-based so we can bypass the synthetic loop when no
-    // cases match simply by branching on the index (which defaults to null).
-    int switchIndex = 1;
-    for (ast.SwitchCase switchCase in node.cases) {
-      for (ast.Node labelOrCase in switchCase.labelsAndCases) {
-        ast.Node label = labelOrCase.asLabel();
-        if (label != null) {
-          LabelDefinition labelElement =
-              builder.elements.getLabelDefinition(label);
-          if (labelElement != null && labelElement.isContinueTarget) {
-            JumpTarget continueTarget = labelElement.target;
-            targetIndexMap[continueTarget] = switchIndex;
-            assert(builder.jumpTargets[continueTarget] == null);
-            builder.jumpTargets[continueTarget] = this;
-          }
-        }
-      }
-      switchIndex++;
-    }
-  }
+      GraphBuilder builder, JumpTarget target) : super(builder, target);
 
   void generateBreak([LabelDefinition label]) {
     if (label == null) {
       // Creates a special break instruction for the synthetic loop generated
       // for a switch statement with continue statements. See
       // [SsaFromAstMixin.buildComplexSwitchStatement] for detail.
 
       HInstruction breakInstruction =
           new HBreak(target, breakSwitchContinueLoop: true);
       LocalsHandler locals = new LocalsHandler.from(builder.localsHandler);
@@ skipping 32 matching lines @@
   }
 
   void close() {
     // The mapping from TargetElement to JumpHandler is no longer needed.
     for (JumpTarget target in targetIndexMap.keys) {
       builder.jumpTargets.remove(target);
     }
     super.close();
   }
 }
+
+/// Special [JumpHandler] implementation used to handle continue statements
+/// targeting switch cases.
+class SsaSwitchCaseJumpHandler extends SwitchCaseJumpHandler {

[sra1, 2017/01/19 23:03:47]

Ssa -> Ast
They are both SSA, one from Ast, one from Kernel

[Emily Fortuna, 2017/01/19 23:19:01]

Done.

+
+  SsaSwitchCaseJumpHandler(
+      GraphBuilder builder, JumpTarget target, ast.SwitchStatement node)
+      : super(builder, target) {
+    // The switch case indices must match those computed in
+    // [SsaFromAstMixin.buildSwitchCaseConstants].
+    // Switch indices are 1-based so we can bypass the synthetic loop when no
+    // cases match simply by branching on the index (which defaults to null).
+    int switchIndex = 1;
+    for (ast.SwitchCase switchCase in node.cases) {
+      for (ast.Node labelOrCase in switchCase.labelsAndCases) {
+        ast.Node label = labelOrCase.asLabel();
+        if (label != null) {
+          LabelDefinition labelElement =
+              builder.elements.getLabelDefinition(label);
+          if (labelElement != null && labelElement.isContinueTarget) {
+            JumpTarget continueTarget = labelElement.target;
+            targetIndexMap[continueTarget] = switchIndex;
+            assert(builder.jumpTargets[continueTarget] == null);
+            builder.jumpTargets[continueTarget] = this;
+          }
+        }
+      }
+      switchIndex++;
+    }
+  }
+}