Make sure the SSA codegen visit constants used in a switch through the 'visitConstant' method, to e…

sdk/lib/_internal/compiler/implementation/ssa/builder.dart

 // 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 ssa;
 
 /**
  * A special element for the extra parameter taken by intercepted
  * methods. We need to override [Element.computeType] because our
  * optimizers may look at its declared type.
@@ skipping 5172 matching lines @@
     HBasicBlock expressionStart = openNewBlock();
     HInstruction expression = buildExpression();
     if (switchCases.isEmpty) {
       return;
     }
 
     HSwitch switchInstruction = new HSwitch(<HInstruction>[expression]);
     HBasicBlock expressionEnd = close(switchInstruction);
     LocalsHandler savedLocals = localsHandler;
 
-    List<List<Constant>> matchExpressions = <List<Constant>>[];
     List<HStatementInformation> statements = <HStatementInformation>[];
     bool hasDefault = false;
     Element getFallThroughErrorElement = backend.getFallThroughError();
     HasNextIterator<Node> caseIterator =
         new HasNextIterator<Node>(switchCases.iterator);
     while (caseIterator.hasNext) {
       SwitchCase switchCase = caseIterator.next();
-      List<Constant> caseConstants = <Constant>[];
       HBasicBlock block = graph.addNewBlock();
       for (Constant constant in getConstants(switchCase)) {
-        caseConstants.add(constant);
         HConstant hConstant = graph.addConstant(constant, compiler);
         switchInstruction.inputs.add(hConstant);
         hConstant.usedBy.add(switchInstruction);
         expressionEnd.addSuccessor(block);
       }
-      matchExpressions.add(caseConstants);
 
       if (isDefaultCase(switchCase)) {
         // An HSwitch has n inputs and n+1 successors, the last being the
         // default case.
         expressionEnd.addSuccessor(block);
         hasDefault = true;
       }
       open(block);
       localsHandler = new LocalsHandler.from(savedLocals);
       buildSwitchCase(switchCase);
@@ skipping 37 matching lines @@
     }
     if (!hasDefault) {
       // Always create a default case, to avoid a critical edge in the
       // graph.
       HBasicBlock defaultCase = addNewBlock();
       expressionEnd.addSuccessor(defaultCase);
       open(defaultCase);
       close(new HGoto());
       defaultCase.addSuccessor(joinBlock);
       caseHandlers.add(savedLocals);
-      matchExpressions.add(<Constant>[]);
       statements.add(new HSubGraphBlockInformation(new SubGraph(
           defaultCase, defaultCase)));
     }
     assert(caseHandlers.length == joinBlock.predecessors.length);
     if (caseHandlers.length != 0) {
       graph.addBlock(joinBlock);
       open(joinBlock);
       if (caseHandlers.length == 1) {
         localsHandler = caseHandlers[0];
       } else {
         localsHandler = savedLocals.mergeMultiple(caseHandlers, joinBlock);
       }
     } else {
       // The joinblock is not used.
       joinBlock = null;
     }
 
     HSubExpressionBlockInformation expressionInfo =
         new HSubExpressionBlockInformation(new SubExpression(expressionStart,
                                                              expressionEnd));
     expressionStart.setBlockFlow(
         new HSwitchBlockInformation(expressionInfo,
-                                    matchExpressions,
                                     statements,
                                     jumpHandler.target,
                                     jumpHandler.labels()),
         joinBlock);
 
     jumpHandler.close();
   }
 
   Element lookupOperator(ClassElement classElement, String operatorName) {
     String dartMethodName =
@@ skipping 636 matching lines @@
           new HSubGraphBlockInformation(elseBranch.graph));
 
     HBasicBlock conditionStartBlock = conditionBranch.block;
     conditionStartBlock.setBlockFlow(info, joinBlock);
     SubGraph conditionGraph = conditionBranch.graph;
     HIf branch = conditionGraph.end.last;
     assert(branch is HIf);
     branch.blockInformation = conditionStartBlock.blockFlow;
   }
 }