Fix potential overwriting of debug jumps of following code.

src/x64/macro-assembler-x64.cc

Index: src/x64/macro-assembler-x64.cc
diff --git a/src/x64/macro-assembler-x64.cc b/src/x64/macro-assembler-x64.cc
index e104e5bb91c3b9949ad41f615400dd26ae798aa3..50b689b23f383b3723cb95e6323dfb4e820aaea2 100644
--- a/src/x64/macro-assembler-x64.cc
+++ b/src/x64/macro-assembler-x64.cc
@@ -68,7 +68,9 @@ void MacroAssembler::CompareRoot(Register with, Heap::RootListIndex index) {
 }
 
 
-void MacroAssembler::CompareRoot(Operand with, Heap::RootListIndex index) {
+void MacroAssembler::CompareRoot(const Operand& with,
+                                 Heap::RootListIndex index) {
+  ASSERT(!with.AddressUsesRegister(kScratchRegister));
   LoadRoot(kScratchRegister, index);
   cmpq(with, kScratchRegister);
 }