X64: Load HeapNumberMap once in BinaryOpStub, and reuse it.

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 8c139512687247750c90d7e4296b279952ba81ef..3e5771728cd6cd5838f325467a20797e529c180f 100644
--- a/src/x64/macro-assembler-x64.cc
+++ b/src/x64/macro-assembler-x64.cc
@@ -35,6 +35,7 @@
 #include "macro-assembler-x64.h"
 #include "serialize.h"
 #include "debug.h"
+#include "heap.h"
 
 namespace v8 {
 namespace internal {
@@ -1731,6 +1732,17 @@ void MacroAssembler::AbortIfNotSmi(Register object) {
 }
 
 
+void MacroAssembler::AbortIfNotRootValue(Register src,
+                                         Heap::RootListIndex root_value_index,
+                                         const char* message) {
+  ASSERT(!src.is(kScratchRegister));
+  LoadRoot(kScratchRegister, root_value_index);
+  cmpq(src, kScratchRegister);
+  Check(equal, message);
+}
+
+
+
 Condition MacroAssembler::IsObjectStringType(Register heap_object,
                                              Register map,
                                              Register instance_type) {