Pass ClosedWorld directly to codegen tasks

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

 // Copyright (c) 2013, 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 ssa.tracer;
 
 import 'dart:async' show EventSink;
 
-import '../compiler.dart' show Compiler;
 import '../diagnostics/invariant.dart' show DEBUG_MODE;
-import '../js_backend/js_backend.dart';
+import '../js_backend/namer.dart' show Namer;
 import '../tracer.dart';
 import '../world.dart' show ClosedWorld;
 import 'nodes.dart';
 
 /**
  * Outputs SSA code in a format readable by Hydra IR.
  * Tracing is disabled by default, see ../tracer.dart for how
  * to enable it.
  */
 class HTracer extends HGraphVisitor with TracerUtil {
-  Compiler compiler;
+  final ClosedWorld closedWorld;
+  final Namer namer;
   final EventSink<String> output;
 
-  HTracer(this.output, this.compiler);
+  HTracer(this.output, this.closedWorld, this.namer);
 
   void traceGraph(String name, HGraph graph) {
     DEBUG_MODE = true;
     tag("cfg", () {
       printProperty("name", name);
       visitDominatorTree(graph);
     });
   }
 
   void addPredecessors(HBasicBlock block) {
@@ skipping 33 matching lines @@
       String depends = instruction.sideEffects.dependsOnSomething() ? '?' : '';
       addIndent();
       String temporaryId = stringifier.temporaryId(instruction);
       String instructionString = stringifier.visit(instruction);
       add("$bci $uses $temporaryId $instructionString $changes $depends <|@\n");
     }
   }
 
   void visitBasicBlock(HBasicBlock block) {
     HInstructionStringifier stringifier =
-        new HInstructionStringifier(block, compiler);
+        new HInstructionStringifier(block, closedWorld, namer);
     assert(block.id != null);
     tag("block", () {
       printProperty("name", "B${block.id}");
       printProperty("from_bci", -1);
       printProperty("to_bci", -1);
       addPredecessors(block);
       addSuccessors(block);
       printEmptyProperty("xhandlers");
       printEmptyProperty("flags");
       if (block.dominator != null) {
@@ skipping 16 matching lines @@
       });
       tag("HIR", () {
         addInstructions(stringifier, block.phis);
         addInstructions(stringifier, block);
       });
     });
   }
 }
 
 class HInstructionStringifier implements HVisitor<String> {
-  final Compiler compiler;
+  final ClosedWorld closedWorld;
+  final Namer namer;
   final HBasicBlock currentBlock;
 
-  HInstructionStringifier(this.currentBlock, this.compiler);
-
-  ClosedWorld get closedWorld => compiler.closedWorld;
+  HInstructionStringifier(this.currentBlock, this.closedWorld, this.namer);
 
   visit(HInstruction node) => '${node.accept(this)} ${node.instructionType}';
 
   String temporaryId(HInstruction instruction) {
     String prefix;
     if (instruction.isNull()) {
       prefix = 'u';
     } else if (instruction.isConflicting()) {
       prefix = 'c';
     } else if (instruction.isExtendableArray(closedWorld)) {
@@ skipping 156 matching lines @@
   String visitIndexAssign(HIndexAssign node) {
     String receiver = temporaryId(node.receiver);
     String index = temporaryId(node.index);
     String value = temporaryId(node.value);
     return "IndexAssign: $receiver[$index] = $value";
   }
 
   String visitInterceptor(HInterceptor node) {
     String value = temporaryId(node.inputs[0]);
     if (node.interceptedClasses != null) {
-      JavaScriptBackend backend = compiler.backend;
-      String cls =
-          backend.namer.suffixForGetInterceptor(node.interceptedClasses);
+      String cls = namer.suffixForGetInterceptor(node.interceptedClasses);
       return "Interceptor ($cls): $value";
     }
     return "Interceptor: $value";
   }
 
   String visitInvokeClosure(HInvokeClosure node) =>
       handleInvokeDynamic(node, "InvokeClosure");
 
   String handleInvokeDynamic(HInvokeDynamic invoke, String kind) {
     String receiver = temporaryId(invoke.receiver);
@@ skipping 244 matching lines @@
   }
 
   String visitAwait(HAwait node) {
     return "Await: ${temporaryId(node.inputs[0])}";
   }
 
   String visitYield(HYield node) {
     return "Yield${node.hasStar ? "*" : ""}: ${temporaryId(node.inputs[0])}";
   }
 }