Revert [TypeFeedbackVector] Root literal arrays in function literal slots

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 9301387c76102a9ee87b5aed821278f12efa583b..29e66e7c3685ee3cbffb378eb2c907d5549fa17e 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -4997,10 +4997,8 @@ class LiteralsArray : public FixedArray {
     return OffsetOfElementAt(index + kFirstLiteralIndex);
   }
 
-  inline bool has_feedback_vector() const;
   inline TypeFeedbackVector* feedback_vector() const;
   inline void set_feedback_vector(TypeFeedbackVector* vector);
-
   inline Object* literal(int literal_index) const;
   inline void set_literal(int literal_index, Object* literal);
   inline void set_literal_undefined(int literal_index);
@@ -7137,6 +7135,12 @@ enum BuiltinFunctionId {
   kStringIteratorNext,
 };
 
+// Result of searching in an optimized code map of a SharedFunctionInfo. Note
+// that both {code} and {literals} can be NULL to pass search result status.
+struct CodeAndLiterals {
+  Code* code;               // Cached optimized code.
+  LiteralsArray* literals;  // Cached literals array.
+};
 
 // SharedFunctionInfo describes the JSFunction information that can be
 // shared by multiple instances of the function.
@@ -7168,7 +7172,11 @@ class SharedFunctionInfo: public HeapObject {
   DECL_ACCESSORS(optimized_code_map, FixedArray)
 
   // Returns entry from optimized code map for specified context and OSR entry.
-  Code* SearchOptimizedCodeMap(Context* native_context, BailoutId osr_ast_id);
+  // Note that {code == nullptr, literals == nullptr} indicates no matching
+  // entry has been found, whereas {code, literals == nullptr} indicates that
+  // code is context-independent.
+  CodeAndLiterals SearchOptimizedCodeMap(Context* native_context,
+                                         BailoutId osr_ast_id);
 
   // Clear optimized code map.
   void ClearOptimizedCodeMap();
@@ -7190,9 +7198,12 @@ class SharedFunctionInfo: public HeapObject {
       Handle<SharedFunctionInfo> shared, Handle<Context> native_context);
 
   // Add or update entry in the optimized code map for context-dependent code.
+  // If {code} is not given, then an existing entry's code won't be overwritten.
   static void AddToOptimizedCodeMap(Handle<SharedFunctionInfo> shared,
                                     Handle<Context> native_context,
-                                    Handle<Code> code, BailoutId osr_ast_id);
+                                    MaybeHandle<Code> code,
+                                    Handle<LiteralsArray> literals,
+                                    BailoutId osr_ast_id);
 
   // Set up the link between shared function info and the script. The shared
   // function info is added to the list on the script.
@@ -7203,7 +7214,8 @@ class SharedFunctionInfo: public HeapObject {
   static const int kEntriesStart = 0;
   static const int kContextOffset = 0;
   static const int kCachedCodeOffset = 1;
-  static const int kEntryLength = 2;
+  static const int kLiteralsOffset = 2;
+  static const int kEntryLength = 3;
   static const int kInitialLength = kEntriesStart + kEntryLength;
 
   static const int kNotFound = -1;
@@ -7215,6 +7227,8 @@ class SharedFunctionInfo: public HeapObject {
   static const int kOffsetToPreviousCachedCode =
       FixedArray::kHeaderSize +
       kPointerSize * (kCachedCodeOffset - kEntryLength);
+  static const int kOffsetToPreviousLiterals =
+      FixedArray::kHeaderSize + kPointerSize * (kLiteralsOffset - kEntryLength);
 
   // [scope_info]: Scope info.
   DECL_ACCESSORS(scope_info, ScopeInfo)
@@ -8164,7 +8178,6 @@ class JSFunction: public JSObject {
   // access to. For API objects we store the boilerplate in the literal array.
   DECL_ACCESSORS(literals, LiteralsArray)
 
-  inline bool has_literals_array() const;
   static void EnsureLiterals(Handle<JSFunction> function);
   inline TypeFeedbackVector* feedback_vector();