Overhaul tree IR visitor and rename IR classes.

pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart

 // Copyright (c) 2014, 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.
 
 library tree_ir_tracer;
 
 import 'dart:async' show EventSink;
 import '../tracer.dart';
 import 'tree_ir_nodes.dart';
-import 'optimization/optimization.dart';
 
 class Block {
   Label label;
   int index;
   /// Mixed list of [Statement] and [Block].
   /// A [Block] represents a synthetic goto statement.
   final List statements = [];
   final List<Block> predecessors = <Block>[];
   final List<Block> successors = <Block>[];
 
   /// The catch block associated with the immediately enclosing try block or
   /// `null` if not inside a try block.
   Block catcher;
 
+  /// True if this block is the entry point to one of the bodies
+  /// (constructors can have multiple bodies).
+  bool isEntryPoint = false;
+
   String get name => 'B$index';
 
   Block([this.label]);
 
   void addEdgeTo(Block successor) {
     successors.add(successor);
     successor.predecessors.add(this);
   }
 }
 
 class BlockCollector extends StatementVisitor {
   // Accumulate a list of blocks.  The current block is the last block in
   // the list.
-  final List<Block> blocks = [new Block()..index = 0];
+  final List<Block> blocks = [];
 
   // Map tree [Label]s (break or continue targets) and [Statement]s
   // (if targets) to blocks.
   final Map<Label, Block> breakTargets = <Label, Block>{};
   final Map<Label, Block> continueTargets = <Label, Block>{};
   final Map<Statement, Block> substatements = <Statement, Block>{};
 
   Block catcher;
 
   void _addStatement(Statement statement) {
     blocks.last.statements.add(statement);
   }
   void _addGotoStatement(Block target) {
     blocks.last.statements.add(target);
   }
 
   void _addBlock(Block block) {
     block.index = blocks.length;
     block.catcher = catcher;
     blocks.add(block);
   }
 
-  void collect(ExecutableDefinition node) {
-    if (node.body != null) {
-      if (node is ConstructorDefinition) {
-        for (Initializer initializer in node.initializers) {
-          if (initializer is FieldInitializer) {
-            visitStatement(initializer.body);
-          }
-        }
-      }
-      visitStatement(node.body);
-    }
+  void collect(RootNode node) {
+    node.forEachBody((Statement body) {
+      _addBlock(new Block()..isEntryPoint = true);
+      visitStatement(body);
+    });
   }
 
   visitLabeledStatement(LabeledStatement node) {
     Block target = new Block(node.label);
     breakTargets[node.label] = target;
     visitStatement(node.body);
     _addBlock(target);
     visitStatement(node.next);
   }
 
@@ skipping 94 matching lines @@
     visitStatement(node.next);
   }
 
   visitSetField(SetField node) {
     _addStatement(node);
     visitStatement(node.next);
   }
 
 }
 
-class TreeTracer extends TracerUtil with StatementVisitor, PassMixin {
-  // TODO(asgerf): Fix visitors so we don't have to use PassMixin here.
+class TreeTracer extends TracerUtil with StatementVisitor {
   String get passName => null;
 
   final EventSink<String> output;
 
   TreeTracer(this.output);
 
+  List<Variable> parameters;
   Names names;
   BlockCollector collector;
   int statementCounter;
 
-  void traceGraph(String name, ExecutableDefinition node) {
-    if (node is FunctionDefinition && node.isAbstract) return;
-    if (node is FieldDefinition && node.body == null) return;
+  void traceGraph(String name, RootNode node) {
+    if (node.isEmpty) return;
+    parameters = node.parameters;
     tag("cfg", () {
       printProperty("name", name);
-      rewrite(node);
+      printRootNode(node);
       collector.blocks.forEach(printBlock);
     });
   }
 
-  @override
-  void rewriteExecutableDefinition(ExecutableDefinition node) {
+  void printRootNode(RootNode node) {
     collector = new BlockCollector();
     names = new Names();
     statementCounter = 0;
     collector = new BlockCollector();
     collector.collect(node);
     collector.blocks.forEach(printBlock);
   }
 
   void printBlock(Block block) {
     tag("block", () {
       printProperty("name", block.name);
       printProperty("from_bci", -1);
       printProperty("to_bci", -1);
       printProperty("predecessors", block.predecessors.map((b) => b.name));
       printProperty("successors", block.successors.map((b) => b.name));
       printEmptyProperty("xhandlers");
       printEmptyProperty("flags");
       tag("states", () {
         tag("locals", () {
           printProperty("size", 0);
           printProperty("method", "None");
         });
       });
       tag("HIR", () {
+        if (block.isEntryPoint) {
+          String params = parameters.map(names.varName).join(', ');
+          printStatement(null, 'Entry ($params)');
+        }
         if (block.label != null) {
           printStatement(null,
               "Label ${block.name}, useCount=${block.label.useCount}");
         }
         if (block.catcher != null) {
           printStatement(null, 'Catch exceptions at ${block.catcher.name}');
         }
         block.statements.forEach(visitBlockMember);
       });
     });
@@ skipping 284 matching lines @@
       String prefix = v.element == null ? 'v' : '${v.element.name}_';
       while (name == null || _usedNames.contains(name)) {
         name = "$prefix${_counter++}";
       }
       _names[v] = name;
       _usedNames.add(name);
     }
     return name;
   }
 }