Rematerialize constants instead of spilling them.

runtime/vm/flow_graph_allocator.h

 // 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.
 
 #ifndef VM_FLOW_GRAPH_ALLOCATOR_H_
 #define VM_FLOW_GRAPH_ALLOCATOR_H_
 
 #include "vm/growable_array.h"
 #include "vm/intermediate_language.h"
 
@@ skipping 108 matching lines @@
   // to them
   void AllocateUnallocatedRanges();
   void AdvanceActiveIntervals(const intptr_t start);
 
   // Connect split siblings over non-linear control flow edges.
   void ResolveControlFlow();
   void ConnectSplitSiblings(LiveRange* range,
                             BlockEntryInstr* source_block,
                             BlockEntryInstr* target_block);
 
+  // Returns true if the target location is the spill slot for the given range.
+  bool TargetLocationIsSpillSlot(LiveRange* range, Location target);
 
   // Update location slot corresponding to the use with location allocated for
   // the use's live range.
   void ConvertUseTo(UsePosition* use, Location loc);
   void ConvertAllUses(LiveRange* range);
 
   // Add live range to the list of unallocated live ranges to be processed
   // by the allocator.
   void AddToUnallocated(LiveRange* range);
   void CompleteRange(LiveRange* range, Location::Kind kind);
@@ skipping 407 matching lines @@
 
   AllocationFinger finger_;
 
   DISALLOW_COPY_AND_ASSIGN(LiveRange);
 };
 
 
 }  // namespace dart
 
 #endif  // VM_FLOW_GRAPH_ALLOCATOR_H_