Use the instruction iterator rather than an explicit loop in more places.

runtime/vm/intermediate_language.cc

 // 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.
 
 #include "vm/intermediate_language.h"
 
 #include "vm/bit_vector.h"
 #include "vm/dart_entry.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/flow_graph_compiler.h"
@@ skipping 46 matching lines @@
 void ClassName::Accept(FlowGraphVisitor* visitor, BindInstr* instr) {          \
   visitor->Visit##ShortName(this, instr);                                      \
 }
 
 FOR_EACH_COMPUTATION(DEFINE_ACCEPT)
 
 #undef DEFINE_ACCEPT
 
 
 #define DEFINE_ACCEPT(ShortName)                                               \
-Instruction* ShortName##Instr::Accept(FlowGraphVisitor* visitor) {             \
+void ShortName##Instr::Accept(FlowGraphVisitor* visitor) {                     \
   visitor->Visit##ShortName(this);                                             \
-  return next();                                                               \
 }
 
 FOR_EACH_INSTRUCTION(DEFINE_ACCEPT)
 
 #undef DEFINE_ACCEPT
 
 
 // True iff. the v2 is above v1 on stack, or one of them is constant.
 static bool VerifyValues(Value* v1, Value* v2) {
   ASSERT(v1->IsUse() && v2->IsUse());
   return (v1->AsUse()->definition()->temp_index() + 1) ==
      v2->AsUse()->definition()->temp_index();
 }
 
 
 // Default implementation of visiting basic blocks.  Can be overridden.
 void FlowGraphVisitor::VisitBlocks() {
   for (intptr_t i = 0; i < block_order_.length(); ++i) {
-    Instruction* current = block_order_[i]->Accept(this);
-    while ((current != NULL) && !current->IsBlockEntry()) {
-      current = current->Accept(this);
+    BlockEntryInstr* entry = block_order_[i];
+    entry->Accept(this);
+    for (ForwardInstructionIterator it(entry); !it.Done(); it.Advance()) {
+      it.Current()->Accept(this);
     }
   }
 }
 
 
 intptr_t InstanceCallComp::InputCount() const {
   return ArgumentCount();
 }
 
 
@@ skipping 1192 matching lines @@
   const ExternalLabel label(closure_function.ToCString(), stub.EntryPoint());
   compiler->GenerateCall(token_pos(), try_index(), &label,
                          PcDescriptors::kOther);
   __ Drop(2);  // Discard type arguments and receiver.
 }
 
 
 #undef __
 
 }  // namespace dart