Add spill slot locations.

runtime/vm/assembler_x64.cc

Index: runtime/vm/assembler_x64.cc
diff --git a/runtime/vm/assembler_x64.cc b/runtime/vm/assembler_x64.cc
index 47264617575354a1d78050f755a01309c9b91f68..9920440318054592693ee6c048b4f201161d937c 100644
--- a/runtime/vm/assembler_x64.cc
+++ b/runtime/vm/assembler_x64.cc
@@ -928,6 +928,14 @@ void Assembler::xorq(Register dst, const Address& address) {
 }
 
 
+void Assembler::xorq(const Address& dst, Register src) {
+  AssemblerBuffer::EnsureCapacity ensured(&buffer_);
+  EmitOperandREX(src, dst, REX_W);
+  EmitUint8(0x31);
+  EmitOperand(src & 7, dst);
+}
+
+
 void Assembler::addl(Register dst, Register src) {
   AssemblerBuffer::EnsureCapacity ensured(&buffer_);
   Operand operand(src);
@@ -1501,6 +1509,12 @@ void Assembler::LoadObject(Register dst, const Object& object) {
 }
 
 
+void Assembler::StoreObject(const Address& dst, const Object& object) {
+  LoadObject(TMP, object);
+  movq(dst, TMP);

[srdjan, 2012/07/23 16:18:59]

The code can be better for Smi.

+}
+
+
 void Assembler::PushObject(const Object& object) {
   if (object.IsSmi()) {
     pushq(Immediate(reinterpret_cast<int64_t>(object.raw())));