[Heap] Remove concept of MarkingParity.

src/x64/codegen-x64.cc

Index: src/x64/codegen-x64.cc
diff --git a/src/x64/codegen-x64.cc b/src/x64/codegen-x64.cc
index 16cf39c99fedcdcb571ff055b396b188c49bbfee..2432d7ed4f40460756f6ca90cdfebf0fb3e1e90a 100644
--- a/src/x64/codegen-x64.cc
+++ b/src/x64/codegen-x64.cc
@@ -195,32 +195,24 @@ bool Code::IsYoungSequence(Isolate* isolate, byte* sequence) {
   return result;
 }
 
-
-void Code::GetCodeAgeAndParity(Isolate* isolate, byte* sequence, Age* age,
-                               MarkingParity* parity) {
-  if (IsYoungSequence(isolate, sequence)) {
-    *age = kNoAgeCodeAge;
-    *parity = NO_MARKING_PARITY;
-  } else {
-    sequence++;  // Skip the kCallOpcode byte
-    Address target_address = sequence + *reinterpret_cast<int*>(sequence) +
-        Assembler::kCallTargetAddressOffset;
-    Code* stub = GetCodeFromTargetAddress(target_address);
-    GetCodeAgeAndParity(stub, age, parity);
-  }
+Code::Age Code::GetCodeAge(Isolate* isolate, byte* sequence) {
+  if (IsYoungSequence(isolate, sequence)) return kNoAgeCodeAge;
+
+  sequence++;  // Skip the kCallOpcode byte
+  Address target_address = sequence + *reinterpret_cast<int*>(sequence) +
+                           Assembler::kCallTargetAddressOffset;
+  Code* stub = GetCodeFromTargetAddress(target_address);
+  return GetAgeOfCodeAgeStub(stub);
 }
 
-
-void Code::PatchPlatformCodeAge(Isolate* isolate,
-                                byte* sequence,
-                                Code::Age age,
-                                MarkingParity parity) {
+void Code::PatchPlatformCodeAge(Isolate* isolate, byte* sequence,
+                                Code::Age age) {
   uint32_t young_length = isolate->code_aging_helper()->young_sequence_length();
   if (age == kNoAgeCodeAge) {
     isolate->code_aging_helper()->CopyYoungSequenceTo(sequence);
     Assembler::FlushICache(isolate, sequence, young_length);
   } else {
-    Code* stub = GetCodeAgeStub(isolate, age, parity);
+    Code* stub = GetCodeAgeStub(isolate, age);
     CodePatcher patcher(isolate, sequence, young_length);
     patcher.masm()->call(stub->instruction_start());
     patcher.masm()->Nop(