First simple implementation of for-of in TurboFan.

src/ast-numbering.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/ast.h"
 #include "src/ast-numbering.h"
 #include "src/compiler.h"
 #include "src/scopes.h"
@@ skipping 29 matching lines @@
 
   int ReserveIdRange(int n) {
     int tmp = next_id_;
     next_id_ += n;
     return tmp;
   }
 
   void IncrementNodeCount() { properties_.add_node_count(1); }
   void DisableCrankshaft(BailoutReason reason) {
     dont_crankshaft_reason_ = reason;
-    properties_.flags()->Add(kDontSelfOptimize);
+    DisableSelfOptimization();
   }
   // TODO(turbofan): Remove the dont_turbofan_reason once no nodes are
-  // DontTurbofanNode.  That set of nodes must be kept in sync with
+  // DisableTurbofan.  That set of nodes must be kept in sync with
   // Pipeline::GenerateCode.
   void DisableTurbofan(BailoutReason reason) {
     dont_crankshaft_reason_ = reason;
     dont_turbofan_reason_ = reason;
     DisableSelfOptimization();
   }
   void DisableSelfOptimization() {
     properties_.flags()->Add(kDontSelfOptimize);
   }
   void DisableCaching(BailoutReason reason) {
@@ skipping 319 matching lines @@
   ReserveFeedbackSlots(node);
   node->set_base_id(ReserveIdRange(ForInStatement::num_ids()));
   Visit(node->each());
   Visit(node->enumerable());
   Visit(node->body());
 }
 
 
 void AstNumberingVisitor::VisitForOfStatement(ForOfStatement* node) {
   IncrementNodeCount();
-  DisableTurbofan(kForOfStatement);
+  DisableCrankshaft(kForOfStatement);

[adamk, 2015/01/13 19:02:36]

Does this mean that any function that happens to use for-of will now get
TurboFan-compiled (when optimized) instead of of Crankshafted?

[Michael Starzinger, 2015/01/13 19:28:01]

Not yet, there are two things missing. First you would need to pass
--turbo-filter=* to enable that. Second there still needs to be some adaptation
to the compilation pipeline (i.e. the mess in the compiler.cc file that nobody
wants to touch with a stick) to make this work reliably.

   node->set_base_id(ReserveIdRange(ForOfStatement::num_ids()));
   Visit(node->assign_iterator());
   Visit(node->next_result());
   Visit(node->result_done());
   Visit(node->assign_each());
   Visit(node->body());
 }
 
 
 void AstNumberingVisitor::VisitConditional(Conditional* node) {
@@ skipping 165 matching lines @@
   return Finish(node);
 }
 
 
 bool AstNumbering::Renumber(FunctionLiteral* function, Zone* zone) {
   AstNumberingVisitor visitor(zone);
   return visitor.Renumber(function);
 }
 }
 }  // namespace v8::internal