Remove the is_used_ field from BindInstr.

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_allocator.h"
 #include "vm/flow_graph_builder.h"
@@ skipping 94 matching lines @@
   return (other_constant != NULL) &&
       (value().raw() == other_constant->value().raw());
 }
 
 
 GraphEntryInstr::GraphEntryInstr(TargetEntryInstr* normal_entry)
     : BlockEntryInstr(CatchClauseNode::kInvalidTryIndex),
       normal_entry_(normal_entry),
       catch_entries_(),
       start_env_(NULL),
-      constant_null_(new BindInstr(BindInstr::kUsed,
+      constant_null_(new BindInstr(Definition::kValue,
                          new ConstantComp(Object::ZoneHandle()))),
       spill_slot_count_(0) {
 }
 
 
 MethodRecognizer::Kind MethodRecognizer::RecognizeKind(
     const Function& function) {
   // Only core and math library methods can be recognized.
   const Library& core_lib = Library::Handle(Library::CoreLibrary());
   const Library& core_impl_lib = Library::Handle(Library::CoreImplLibrary());
@@ skipping 66 matching lines @@
   prev_instr->set_next(next_instr);
   next_instr->set_previous(prev_instr);
   // Reset successor and previous instruction to indicate
   // that the instruction is removed from the graph.
   set_previous(NULL);
   set_next(NULL);
   return return_previous ? prev_instr : next_instr;
 }
 
 
-void BindInstr::InsertBefore(Instruction* next) {
+void Definition::InsertBefore(Instruction* next) {
   ASSERT(previous_ == NULL);
   ASSERT(next_ == NULL);
   next_ = next;
   previous_ = next->previous_;
   next->previous_ = this;
   previous_->next_ = this;
 }
 
 
-void BindInstr::InsertAfter(Instruction* prev) {
+void Definition::InsertAfter(Instruction* prev) {
   ASSERT(previous_ == NULL);
   ASSERT(next_ == NULL);
   previous_ = prev;
   next_ = prev->next_;
   next_->previous_ = this;
   previous_->next_ = this;
 }
 
 
 void ForwardInstructionIterator::RemoveCurrentFromGraph() {
@@ skipping 1303 matching lines @@
     value->set_use_index(i);
     value->AddToEnvUseList();
   }
   instr->set_env(copy);
 }
 
 
 #undef __
 
 }  // namespace dart