[for-in] Sanitize for-in optimizations and fix bailout points.

src/mips64/macro-assembler-mips64.cc

Index: src/mips64/macro-assembler-mips64.cc
diff --git a/src/mips64/macro-assembler-mips64.cc b/src/mips64/macro-assembler-mips64.cc
index 7c94f74f69b5adb0b11c79b128925162168e3034..b6ef16e4da8a93d55be17e4a422e3bbee951fb84 100644
--- a/src/mips64/macro-assembler-mips64.cc
+++ b/src/mips64/macro-assembler-mips64.cc
@@ -6239,7 +6239,8 @@ void MacroAssembler::LoadAccessor(Register dst, Register holder,
 }
 
 
-void MacroAssembler::CheckEnumCache(Register null_value, Label* call_runtime) {
+void MacroAssembler::CheckEnumCache(Label* call_runtime) {
+  Register null_value = a5;
   Register  empty_fixed_array_value = a6;
   LoadRoot(empty_fixed_array_value, Heap::kEmptyFixedArrayRootIndex);
   Label next, start;
@@ -6253,6 +6254,7 @@ void MacroAssembler::CheckEnumCache(Register null_value, Label* call_runtime) {
   Branch(
       call_runtime, eq, a3, Operand(Smi::FromInt(kInvalidEnumCacheSentinel)));
 
+  LoadRoot(null_value, Heap::kNullValueRootIndex);
   jmp(&start);
 
   bind(&next);