Support break and labeled statements.

frog/leg/ssa/nodes.dart

 // Copyright (c) 2011, 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.
 
 interface HVisitor<R> {
   R visitAdd(HAdd node);
   R visitBailoutTarget(HBailoutTarget node);
   R visitBitAnd(HBitAnd node);
   R visitBitNot(HBitNot node);
   R visitBitOr(HBitOr node);
   R visitBitXor(HBitXor node);
   R visitBoolify(HBoolify node);
   R visitBoundsCheck(HBoundsCheck node);
+  R visitBreak(HBreak node);
   R visitDivide(HDivide node);
   R visitEquals(HEquals node);
   R visitExit(HExit node);
   R visitFieldGet(HFieldGet node);
   R visitFieldSet(HFieldSet node);
   R visitForeign(HForeign node);
   R visitForeignNew(HForeignNew);
   R visitGoto(HGoto node);
   R visitGreater(HGreater node);
   R visitGreaterEqual(HGreaterEqual node);
@@ skipping 104 matching lines @@
     blocks.add(block);
     assert(blocks[id] === block);
   }
 
   HBasicBlock addNewBlock() {
     HBasicBlock result = new HBasicBlock();
     addBlock(result);
     return result;
   }
 
-  HBasicBlock addNewLoopHeaderBlock() {
+  HBasicBlock addNewLoopHeaderBlock(List<SourceString> labels) {
     HBasicBlock result = addNewBlock();
-    result.loopInformation = new HLoopInformation(result);
+    result.loopInformation = new HLoopInformation(result, labels);
     return result;
   }
 
   void finalize() {
     addBlock(exit);
     exit.open();
     exit.close(new HExit());
     assignDominators();
   }
 
@@ skipping 49 matching lines @@
   visitRelational(HRelational node) => visitInvokeBinary(node);
 
   visitAdd(HAdd node) => visitBinaryArithmetic(node);
   visitBitAnd(HBitAnd node) => visitBinaryBitOp(node);
   visitBitNot(HBitNot node) => visitInvokeUnary(node);
   visitBitOr(HBitOr node) => visitBinaryBitOp(node);
   visitBitXor(HBitXor node) => visitBinaryBitOp(node);
   visitBailoutTarget(HBailoutTarget node) => visitInstruction(node);
   visitBoolify(HBoolify node) => visitInstruction(node);
   visitBoundsCheck(HBoundsCheck node) => visitCheck(node);
+  visitBreak(HBreak node) => visitGoto(node);
   visitCheck(HCheck node) => visitInstruction(node);
   visitDivide(HDivide node) => visitBinaryArithmetic(node);
   visitEquals(HEquals node) => visitRelational(node);
   visitExit(HExit node) => visitControlFlow(node);
   visitFieldGet(HFieldGet node) => visitInstruction(node);
   visitFieldSet(HFieldSet node) => visitInstruction(node);
   visitForeign(HForeign node) => visitInstruction(node);
   visitForeignNew(HForeignNew node) => visitForeign(node);
   visitGoto(HGoto node) => visitControlFlow(node);
   visitGreater(HGreater node) => visitRelational(node);
@@ skipping 122 matching lines @@
   // this [id]. The exception are back-edges.
   int id;
 
   static final int STATUS_NEW = 0;
   static final int STATUS_OPEN = 1;
   static final int STATUS_CLOSED = 2;
   int status = STATUS_NEW;
 
   HInstructionList phis;
 
-  HLoopInformation loopInformation = null;
+  HBlockInformation blockInformation = null;

[Lasse Reichstein Nielsen, 2012/02/20 13:56:16]

I store both loop information and labeled block information here, depending on
what the block represents. Accessors below check the type before returning it.

[floitsch, 2012/02/20 19:01:54]

I would prefer two fields. This way we could get rid of the marker-class too.

[Lasse Reichstein Nielsen, 2012/02/21 13:53:56]

Done.

   HBasicBlock parentLoopHeader = null;
   List<HBailoutTarget> bailouts;
 
   final List<HBasicBlock> predecessors;
   List<HBasicBlock> successors;
 
   HBasicBlock dominator = null;
   final List<HBasicBlock> dominatedBlocks;
 
+  // For recognizing labeled statements.
+  List<SourceString> labels;
+
+  bool isBlockEnd;
+
   HBasicBlock() : this.withId(null);
   HBasicBlock.withId(this.id)
       : phis = new HInstructionList(),
         predecessors = <HBasicBlock>[],
         successors = const <HBasicBlock>[],
         dominatedBlocks = <HBasicBlock>[],
         bailouts = <HBailoutTarget>[];
 
   bool isNew() => status == STATUS_NEW;
   bool isOpen() => status == STATUS_OPEN;
   bool isClosed() => status == STATUS_CLOSED;
 
-  bool isLoopHeader() => loopInformation !== null;
+  bool isLoopHeader() => blockInformation is HLoopInformation;
+  bool hasLabeledBlockInformation() =>
+      blockInformation is HLabeledBlockInformation;
   bool hasBailouts() => !bailouts.isEmpty();
 
+  void set loopInformation(HLoopInformation info) {
+    assert(this.blockInformation === null);
+    blockInformation = info;
+  }
+
+  void set labeledBlockInformation(HLabeledBlockInformation info) {
+    assert(this.blockInformation === null);
+    blockInformation = info;
+  }
+
+  HLoopInformation get loopInformation() {
+    if (blockInformation is HLoopInformation) {
+      return blockInformation;
+    }
+    return null;
+  }
+
+  HLabeledBlockInformation get labeledBlockInformation() {
+    if (blockInformation is HLabeledBlockInformation) {
+      return blockInformation;
+    }
+    return null;
+  }
+
   void open() {
     assert(isNew());
     status = STATUS_OPEN;
   }
 
   void close(HControlFlow end) {
     assert(isOpen());
     addAfter(last, end);
     status = STATUS_CLOSED;
   }
@@ skipping 189 matching lines @@
   }
 
   bool isValid() {
     assert(isClosed());
     HValidator validator = new HValidator();
     validator.visitBasicBlock(this);
     return validator.isValid;
   }
 }
 
-class HLoopInformation {
+class HBlockInformation {
+  // Just a marker class.
+}
+
+class HLabeledBlockInformation extends HBlockInformation {
+  final HBasicBlock start;
+  final HBasicBlock end;
+  final List<SourceString> labels;
+  HLabeledBlockInformation(this.start, this.end, this.labels);
+}
+
+class HLoopInformation extends HBlockInformation {
   final HBasicBlock header;
   final List<HBasicBlock> blocks;
   final List<HBasicBlock> backEdges;
+  final List<SourceString> labels;
 
-  HLoopInformation(this.header)
+  HLoopInformation(this.header, this.labels)
       : blocks = new List<HBasicBlock>(),
         backEdges = new List<HBasicBlock>();
 
   void addBackEdge(HBasicBlock predecessor) {
     backEdges.add(predecessor);
     addBlock(predecessor);
   }
 
   // Adds a block and transitively all its predecessors in the loop as
   // loop blocks.
@@ skipping 1025 matching lines @@
   toString() => 'exit';
   accept(HVisitor visitor) => visitor.visitExit(this);
 }
 
 class HGoto extends HControlFlow {
   HGoto() : super(const <HInstruction>[]);
   toString() => 'goto';
   accept(HVisitor visitor) => visitor.visitGoto(this);
 }
 
+class HBreak extends HGoto {
+  final SourceString label;
+  HBreak([this.label]);
+  toString() => 'break';
+  accept(HVisitor visitor) => visitor.visitBreak(this);
+}
+
 class HTry extends HControlFlow {
   HParameterValue exception;
   HBasicBlock finallyBlock;
   HTry() : super(const <HInstruction>[]);
   toString() => 'try';
   accept(HVisitor visitor) => visitor.visitTry(this);
 }
 
 class HIf extends HConditionalBranch {
   bool hasElse;
@@ skipping 484 matching lines @@
 
   HInstruction get expression() => inputs[0];
 
   HType computeType() => HType.BOOLEAN;
   bool hasExpectedType() => true;
 
   accept(HVisitor visitor) => visitor.visitIs(this);
 
   toString() => "$expression is $typeExpression";
 }