[Interpreter] Add bytecode aging and use it enable CompilationCache for bytecode

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 651d12593a35b9ca04ad9865a5875813a17abc13..c7f1ac7b3b1f6cb89e4f4216196228d46c112710 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -4941,6 +4941,17 @@ class PodArray : public ByteArray {
 // BytecodeArray represents a sequence of interpreter bytecodes.
 class BytecodeArray : public FixedArrayBase {
  public:
+#define DECLARE_BYTECODE_AGE_ENUM(X) k##X##BytecodeAge,
+  enum Age {
+    kNoAgeBytecodeAge = 0,
+    CODE_AGE_LIST(DECLARE_BYTECODE_AGE_ENUM) kAfterLastBytecodeAge,
+    kFirstBytecodeAge = kNoAgeBytecodeAge,
+    kLastBytecodeAge = kAfterLastBytecodeAge - 1,
+    kBytecodeAgeCount = kAfterLastBytecodeAge - kFirstBytecodeAge - 1,
+    kIsOldBytecodeAge = kSexagenarianBytecodeAge
+  };
+#undef DECLARE_BYTECODE_AGE_ENUM
+
   static int SizeFor(int length) {
     return OBJECT_POINTER_ALIGN(kHeaderSize + length);
   }
@@ -4971,6 +4982,10 @@ class BytecodeArray : public FixedArrayBase {
   inline int osr_loop_nesting_level() const;
   inline void set_osr_loop_nesting_level(int depth);
 
+  // Accessors for bytecode's code age.
+  inline Age bytecode_age() const;
+  inline void set_bytecode_age(Age age);
+
   // Accessors for the constant pool.
   DECL_ACCESSORS(constant_pool, FixedArray)
 
@@ -5005,6 +5020,10 @@ class BytecodeArray : public FixedArrayBase {
   int LookupRangeInHandlerTable(int code_offset, int* data,
                                 HandlerTable::CatchPrediction* prediction);
 
+  // Bytecode aging
+  bool IsOld() const;
+  void MakeOlder();
+
   // Layout description.
   static const int kConstantPoolOffset = FixedArrayBase::kHeaderSize;
   static const int kHandlerTableOffset = kConstantPoolOffset + kPointerSize;
@@ -5014,7 +5033,8 @@ class BytecodeArray : public FixedArrayBase {
   static const int kParameterSizeOffset = kFrameSizeOffset + kIntSize;
   static const int kInterruptBudgetOffset = kParameterSizeOffset + kIntSize;
   static const int kOSRNestingLevelOffset = kInterruptBudgetOffset + kIntSize;
-  static const int kHeaderSize = kOSRNestingLevelOffset + kCharSize;
+  static const int kBytecodeAgeOffset = kOSRNestingLevelOffset + kCharSize;
+  static const int kHeaderSize = kBytecodeAgeOffset + kCharSize;
 
   // Maximal memory consumption for a single BytecodeArray.
   static const int kMaxSize = 512 * MB;