Support for multiple register values

runtime/vm/flow_graph.h

 // 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.
 
 #ifndef VM_FLOW_GRAPH_H_
 #define VM_FLOW_GRAPH_H_
 
 #include "vm/growable_array.h"
 #include "vm/intermediate_language.h"
 #include "vm/parser.h"
@@ skipping 102 matching lines @@
   ConstantInstr* constant_null() const {
     return constant_null_;
   }
 
   ConstantInstr* constant_dead() const {
     return constant_dead_;
   }
 
   intptr_t alloc_ssa_temp_index() { return current_ssa_temp_index_++; }
 
+  void AllocateSSAIndexes(Definition* def) {
+    ASSERT(def);
+    def->set_ssa_temp_index(alloc_ssa_temp_index());
+    // Always allocate a second index. This index is unused except
+    // for Definitions with register pair outputs.
+    alloc_ssa_temp_index();
+  }
+
   intptr_t InstructionCount() const;
 
   ConstantInstr* GetConstant(const Object& object);
   void AddToInitialDefinitions(Definition* defn);
 
   void InsertBefore(Instruction* next,
                     Instruction* instr,
                     Environment* env,
                     Definition::UseKind use_kind);
   void InsertAfter(Instruction* prev,
@@ skipping 250 matching lines @@
   // Per block sets of available blocks. Block A is available at the block B if
   // and only if A dominates B and all paths from A to B are free of side
   // effects.
   GrowableArray<BitVector*> available_at_;
 };
 
 
 }  // namespace dart
 
 #endif  // VM_FLOW_GRAPH_H_