Implement kDoubleToDouble and kIntegerToDouble on ia32 and x64.

runtime/vm/assembler_x64.cc

 // Copyright (c) 2011, 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"
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/assembler.h"
 #include "vm/heap.h"
 #include "vm/memory_region.h"
@@ skipping 536 matching lines @@
   EmitUint8(0x57);
   EmitOperand(dst & 7, src);
 }
 
 
 void Assembler::cvtsi2sd(XmmRegister dst, Register src) {
   AssemblerBuffer::EnsureCapacity ensured(&buffer_);
   ASSERT(dst <= XMM7);
   Operand operand(src);
   EmitUint8(0xF2);
-  EmitOperandREX(0, operand, REX_NONE);
+  EmitOperandREX(0, operand, REX_W);
   EmitUint8(0x0F);
   EmitUint8(0x2A);
   EmitOperand(dst, operand);
 }
 
 
 void Assembler::xchgl(Register dst, Register src) {
   AssemblerBuffer::EnsureCapacity ensured(&buffer_);
   Operand operand(src);
   EmitOperandREX(dst, operand, REX_NONE);
@@ skipping 1085 matching lines @@
     comments.SetCommentAt(i, comments_[i]->comment());
   }
 
   return comments;
 }
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64