Reland "Keep a canonical list of shared function infos."

src/objects.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_OBJECTS_H_
 #define V8_OBJECTS_H_
 
 #include <iosfwd>
 
 #include "src/allocation.h"
@@ skipping 857 matching lines @@
 
 #define DECLARE_CAST(type)                              \
   INLINE(static type* cast(Object* object));            \
   INLINE(static const type* cast(const Object* object));
 
 
 class AccessorPair;
 class AllocationSite;
 class AllocationSiteCreationContext;
 class AllocationSiteUsageContext;
+class Cell;
 class ConsString;
 class DictionaryElementsAccessor;
 class ElementsAccessor;
 class FixedArrayBase;
 class FunctionLiteral;
 class GlobalObject;
+class JSBuiltinsObject;
 class LayoutDescriptor;
 class LookupIterator;
+class ObjectHashTable;
 class ObjectVisitor;
+class PropertyCell;
+class SafepointEntry;
+class SharedFunctionInfo;
 class StringStream;
+class TypeFeedbackInfo;
 class TypeFeedbackVector;
 class WeakCell;
 
 // We cannot just say "class HeapType;" if it is created from a template... =8-?
 template<class> class TypeImpl;
 struct HeapTypeConfig;
 typedef TypeImpl<HeapTypeConfig> HeapType;
 
 
 // A template-ized version of the IsXXX functions.
@@ skipping 828 matching lines @@
   // Computes the enumerable keys for a JSObject. Used for implementing
   // "for (n in object) { }".
   MUST_USE_RESULT static MaybeHandle<FixedArray> GetKeys(
       Handle<JSReceiver> object,
       KeyCollectionType type);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSReceiver);
 };
 
-// Forward declaration for JSObject::GetOrCreateHiddenPropertiesHashTable.
-class ObjectHashTable;
-
 
 // The JSObject describes real heap allocated JavaScript objects with
 // properties.
 // Note that the map of JSObject changes during execution to enable inline
 // caching.
 class JSObject: public JSReceiver {
  public:
   // [properties]: Backing storage for properties.
   // properties is a FixedArray in the fast case and a Dictionary in the
   // slow case.
@@ skipping 3090 matching lines @@
   static const int kReturnOffsetIndex = 0;
   static const int kReturnHandlerIndex = 1;
   static const int kReturnEntrySize = 2;
 
   // Encoding of the {handler} field.
   class HandlerPredictionField : public BitField<CatchPrediction, 0, 1> {};
   class HandlerOffsetField : public BitField<int, 1, 30> {};
 };
 
 
-// Forward declaration.
-class Cell;
-class PropertyCell;
-class SafepointEntry;
-class TypeFeedbackInfo;
-
 // Code describes objects with on-the-fly generated machine code.
 class Code: public HeapObject {
  public:
   // Opaque data type for encapsulating code flags like kind, inline
   // cache state, and arguments count.
   typedef uint32_t Flags;
 
 #define NON_IC_KIND_LIST(V) \
   V(FUNCTION)               \
   V(OPTIMIZED_FUNCTION)     \
@@ skipping 1543 matching lines @@
   DECL_ACCESSORS(line_ends, Object)
 
   // [eval_from_shared]: for eval scripts the shared funcion info for the
   // function from which eval was called.
   DECL_ACCESSORS(eval_from_shared, Object)
 
   // [eval_from_instructions_offset]: the instruction offset in the code for the
   // function from which eval was called where eval was called.
   DECL_ACCESSORS(eval_from_instructions_offset, Smi)
 
+  // [shared_function_infos]: weak fixed array containing all shared
+  // function infos created from this script.
+  DECL_ACCESSORS(shared_function_infos, Object)
+
   // [flags]: Holds an exciting bitfield.
   DECL_ACCESSORS(flags, Smi)
 
   // [source_url]: sourceURL from magic comment
   DECL_ACCESSORS(source_url, Object)
 
   // [source_url]: sourceMappingURL magic comment
   DECL_ACCESSORS(source_mapping_url, Object)
 
   // [compilation_type]: how the the script was compiled. Encoded in the
@@ skipping 27 matching lines @@
   int GetLineNumber(int code_pos);
 
   static Handle<Object> GetNameOrSourceURL(Handle<Script> script);
 
   // Init line_ends array with code positions of line ends inside script source.
   static void InitLineEnds(Handle<Script> script);
 
   // Get the JS object wrapping the given script; create it if none exists.
   static Handle<JSObject> GetWrapper(Handle<Script> script);
 
+  // Look through the list of existing shared function infos to find one
+  // that matches the function literal.  Return empty handle if not found.
+  MaybeHandle<SharedFunctionInfo> FindSharedFunctionInfo(FunctionLiteral* fun);
+
   // Dispatched behavior.
   DECLARE_PRINTER(Script)
   DECLARE_VERIFIER(Script)
 
   static const int kSourceOffset = HeapObject::kHeaderSize;
   static const int kNameOffset = kSourceOffset + kPointerSize;
   static const int kLineOffsetOffset = kNameOffset + kPointerSize;
   static const int kColumnOffsetOffset = kLineOffsetOffset + kPointerSize;
   static const int kContextOffset = kColumnOffsetOffset + kPointerSize;
   static const int kWrapperOffset = kContextOffset + kPointerSize;
   static const int kTypeOffset = kWrapperOffset + kPointerSize;
   static const int kLineEndsOffset = kTypeOffset + kPointerSize;
   static const int kIdOffset = kLineEndsOffset + kPointerSize;
   static const int kEvalFromSharedOffset = kIdOffset + kPointerSize;
   static const int kEvalFrominstructionsOffsetOffset =
       kEvalFromSharedOffset + kPointerSize;
-  static const int kFlagsOffset =
+  static const int kSharedFunctionInfosOffset =
       kEvalFrominstructionsOffsetOffset + kPointerSize;
+  static const int kFlagsOffset = kSharedFunctionInfosOffset + kPointerSize;
   static const int kSourceUrlOffset = kFlagsOffset + kPointerSize;
   static const int kSourceMappingUrlOffset = kSourceUrlOffset + kPointerSize;
   static const int kSize = kSourceMappingUrlOffset + kPointerSize;
 
  private:
   int GetLineNumberWithArray(int code_pos);
 
   // Bit positions in the flags field.
   static const int kCompilationTypeBit = 0;
   static const int kCompilationStateBit = 1;
@@ skipping 110 matching lines @@
   static void InitFromFunctionLiteral(Handle<SharedFunctionInfo> shared_info,
                                       FunctionLiteral* lit);
 
   // Add a new entry to the optimized code map.
   static void AddToOptimizedCodeMap(Handle<SharedFunctionInfo> shared,
                                     Handle<Context> native_context,
                                     Handle<Code> code,
                                     Handle<FixedArray> 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.
+  static void SetScript(Handle<SharedFunctionInfo> shared,
+                        Handle<Object> script_object);
+
   // Layout description of the optimized code map.
   static const int kNextMapIndex = 0;
   static const int kEntriesStart = 1;
   static const int kContextOffset = 0;
   static const int kCachedCodeOffset = 1;
   static const int kLiteralsOffset = 2;
   static const int kOsrAstIdOffset = 3;
   static const int kEntryLength = 4;
   static const int kInitialLength = kEntriesStart + kEntryLength;
 
@@ skipping 193 matching lines @@
 
   // Indicates that this function is a default constructor.
   DECL_BOOLEAN_ACCESSORS(is_default_constructor)
 
   // Indicates that this function is an asm function.
   DECL_BOOLEAN_ACCESSORS(asm_function)
 
   // Indicates that the the shared function info is deserialized from cache.
   DECL_BOOLEAN_ACCESSORS(deserialized)
 
+  // Indicates that the the shared function info has never been compiled before.
+  DECL_BOOLEAN_ACCESSORS(never_compiled)
+
   inline FunctionKind kind();
   inline void set_kind(FunctionKind kind);
 
   // Indicates whether or not the code in the shared function support
   // deoptimization.
   inline bool has_deoptimization_support();
 
   // Enable deoptimization support through recompiled code.
   void EnableDeoptimizationSupport(Code* recompiled);
 
@@ skipping 229 matching lines @@
     kIsArrow,
     kIsGenerator,
     kIsConciseMethod,
     kIsAccessorFunction,
     kIsDefaultConstructor,
     kIsSubclassConstructor,
     kIsBaseConstructor,
     kInClassLiteral,
     kIsAsmFunction,
     kDeserialized,
+    kNeverCompiled,
     kCompilerHintsCount  // Pseudo entry
   };
   // Add hints for other modes when they're added.
   STATIC_ASSERT(LANGUAGE_END == 3);
 
   class FunctionKindBits : public BitField<FunctionKind, kIsArrow, 8> {};
 
   class DeoptCountBits : public BitField<int, 0, 4> {};
   class OptReenableTriesBits : public BitField<int, 4, 18> {};
   class ICAgeBits : public BitField<int, 22, 8> {};
@@ skipping 397 matching lines @@
   // Layout description.
   static const int kNativeContextOffset = JSObject::kHeaderSize;
   static const int kHashOffset = kNativeContextOffset + kPointerSize;
   static const int kSize = kHashOffset + kPointerSize;
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSGlobalProxy);
 };
 
 
-// Forward declaration.
-class JSBuiltinsObject;
-
 // Common super class for JavaScript global objects and the special
 // builtins global objects.
 class GlobalObject: public JSObject {
  public:
   // [builtins]: the object holding the runtime routines written in JS.
   DECL_ACCESSORS(builtins, JSBuiltinsObject)
 
   // [native context]: the natives corresponding to this global object.
   DECL_ACCESSORS(native_context, Context)
 
@@ skipping 3297 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_