Merge ConstantInstr -> UnboxDouble to UnboxedConstant. Reduces register usage and allows for variou…

runtime/vm/flow_graph_compiler_x64.cc

 // 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.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "vm/ast_printer.h"
@@ skipping 1659 matching lines @@
   } else if (source.IsQuadStackSlot()) {
     if (destination.IsFpuRegister()) {
       __ movups(destination.fpu_reg(), source.ToStackSlotAddress());
     } else {
       ASSERT(destination.IsQuadStackSlot());
       __ movups(XMM0, source.ToStackSlotAddress());
       __ movups(destination.ToStackSlotAddress(), XMM0);
     }
   } else {
     ASSERT(source.IsConstant());
+    const Object& constant = source.constant();
     if (destination.IsRegister()) {
-      const Object& constant = source.constant();
       if (constant.IsSmi() && (Smi::Cast(constant).Value() == 0)) {
         __ xorq(destination.reg(), destination.reg());
       } else {
         __ LoadObject(destination.reg(), constant, PP);
       }
+    } else if (destination.IsFpuRegister()) {
+      __ LoadObject(TMP, constant, PP);
+      __ movsd(destination.fpu_reg(),
+          FieldAddress(TMP, Double::value_offset()));
     } else {
       ASSERT(destination.IsStackSlot());
-      StoreObject(destination.ToStackSlotAddress(), source.constant());
+      StoreObject(destination.ToStackSlotAddress(), constant);
     }
   }
 
   move->Eliminate();
 }
 
 
 void ParallelMoveResolver::EmitSwap(int index) {
   MoveOperands* move = moves_[index];
   const Location source = move->src();
@@ skipping 124 matching lines @@
   __ movups(reg, Address(RSP, 0));
   __ AddImmediate(RSP, Immediate(kFpuRegisterSize), PP);
 }
 
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64