Fix bug in ParallelMoveResolver::EmitSwap: implement swaps of FPU spill slots.

runtime/vm/flow_graph_compiler.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_COMPILER_H_
 #define VM_FLOW_GRAPH_COMPILER_H_
 
 #include "vm/allocation.h"
 #include "vm/assembler.h"
 #include "vm/code_descriptors.h"
@@ skipping 13 matching lines @@
 
 
 class ParallelMoveResolver : public ValueObject {
  public:
   explicit ParallelMoveResolver(FlowGraphCompiler* compiler);
 
   // Resolve a set of parallel moves, emitting assembler instructions.
   void EmitNativeCode(ParallelMoveInstr* parallel_move);
 
  private:
+  class ScratchFpuRegisterScope : public ValueObject {
+   public:
+    ScratchFpuRegisterScope(ParallelMoveResolver* resolver,
+                            FpuRegister blocked);
+    ~ScratchFpuRegisterScope();
+
+    FpuRegister reg() const { return reg_; }
+
+   private:
+    ParallelMoveResolver* resolver_;
+    FpuRegister reg_;
+    bool spilled_;
+  };
+
+  class ScratchRegisterScope : public ValueObject {
+   public:
+    ScratchRegisterScope(ParallelMoveResolver* resolver, Register blocked);
+    ~ScratchRegisterScope();
+
+    Register reg() const { return reg_; }
+
+   private:
+    ParallelMoveResolver* resolver_;
+    Register reg_;
+    bool spilled_;
+  };
+
+
+  bool IsScratchLocation(Location loc);
+  intptr_t AllocateScratchRegister(Location::Kind kind,
+                                   intptr_t blocked,
+                                   intptr_t register_count,
+                                   bool* spilled);
+
+  void SpillScratch(Register reg);
+  void RestoreScratch(Register reg);
+  void SpillFpuScratch(FpuRegister reg);
+  void RestoreFpuScratch(FpuRegister reg);
+
+  // friend class ScratchXmmRegisterScope;
+
   // Build the initial list of moves.
   void BuildInitialMoveList(ParallelMoveInstr* parallel_move);
 
   // Perform the move at the moves_ index in question (possibly requiring
   // other moves to satisfy dependencies).
   void PerformMove(int index);
 
   // Emit a move and remove it from the move graph.
   void EmitMove(int index);
 
@@ skipping 503 matching lines @@
   // that should be used when deoptimizing we store it in this variable.
   // In future AddDeoptStub should be moved out of the instruction template.
   Environment* pending_deoptimization_env_;
 
   DISALLOW_COPY_AND_ASSIGN(FlowGraphCompiler);
 };
 
 }  // namespace dart
 
 #endif  // VM_FLOW_GRAPH_COMPILER_H_