Store information about builtins in descriptors

src/builtins/builtins.h

 // Copyright 2011 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_BUILTINS_BUILTINS_H_
 #define V8_BUILTINS_BUILTINS_H_
 
 #include "src/base/flags.h"
 #include "src/handles.h"
 
@@ skipping 551 matching lines @@
   // Garbage collection support.
   void IterateBuiltins(ObjectVisitor* v);
 
   // Disassembler support.
   const char* Lookup(byte* pc);
 
   enum Name {
 #define DEF_ENUM(Name, ...) k##Name,
     BUILTIN_LIST_ALL(DEF_ENUM)
 #undef DEF_ENUM
-        builtin_count
+        BUILTIN_COUNT
   };
 
 #define DECLARE_BUILTIN_ACCESSOR(Name, ...) Handle<Code> Name();
   BUILTIN_LIST_ALL(DECLARE_BUILTIN_ACCESSOR)
 #undef DECLARE_BUILTIN_ACCESSOR
 
+  enum Kind { CPP, API, TFJ, TFS, ASM, ASH, DBG };

[Toon Verwaest, 2016/08/19 11:58:15]

Here I'd write the names out so we don't need to go hunt for their meaning.

+
+  struct Descriptor {
+    Descriptor() {}
+    Descriptor(Name id, Kind kind, Address entry, Object* code,
+               const char* debug_name)
+        : id(id),
+          kind(kind),
+          entry(entry),
+          code(code),
+          debug_name(debug_name) {}
+
+    Name id;
+    Kind kind;
+
+    // For CPP and API functions, this is the C++ entry point.
+    Address entry;
+
+    // Note: These are always Code objects, but to conform with
+    // IterateBuiltins(), we use an Object* here.
+    Object* code;

[Toon Verwaest, 2016/08/19 11:58:15]

You should be able to just make this a Code*, which is a subclass of Object*

+
+    const char* debug_name;

[Toon Verwaest, 2016/08/19 11:58:15]

#ifdef DEBUG?

+  };
+
   // Convenience wrappers.
   Handle<Code> CallFunction(
       ConvertReceiverMode = ConvertReceiverMode::kAny,
       TailCallMode tail_call_mode = TailCallMode::kDisallow);
   Handle<Code> Call(ConvertReceiverMode = ConvertReceiverMode::kAny,
                     TailCallMode tail_call_mode = TailCallMode::kDisallow);
   Handle<Code> CallBoundFunction(TailCallMode tail_call_mode);
   Handle<Code> NonPrimitiveToPrimitive(
       ToPrimitiveHint hint = ToPrimitiveHint::kDefault);
   Handle<Code> OrdinaryToPrimitive(OrdinaryToPrimitiveHint hint);
   Handle<Code> InterpreterPushArgsAndCall(
       TailCallMode tail_call_mode,
       CallableType function_type = CallableType::kAny);
 
   Code* builtin(Name name) {
     // Code::cast cannot be used here since we access builtins
     // during the marking phase of mark sweep. See IC::Clear.

[Toon Verwaest, 2016/08/19 11:58:15]

Then you don't need to reinterpret_cast here.

-    return reinterpret_cast<Code*>(builtins_[name]);
+    return reinterpret_cast<Code*>(builtins_[name].code);
   }
 
   Address builtin_address(Name name) {
-    return reinterpret_cast<Address>(&builtins_[name]);
+    return reinterpret_cast<Address>(&builtins_[name].code);
   }
 
   const char* name(int index);
 
   bool is_initialized() const { return initialized_; }
 
   MUST_USE_RESULT static MaybeHandle<Object> InvokeApiFunction(
       Isolate* isolate, bool is_construct, Handle<HeapObject> function,
       Handle<Object> receiver, int argc, Handle<Object> args[],
       Handle<HeapObject> new_target);
@@ skipping 33 matching lines @@
   static void Generate_##Name(MacroAssembler* masm);
 #define DECLARE_TF(Name, ...) \
   static void Generate_##Name(CodeStubAssembler* csasm);
 
   BUILTIN_LIST(IGNORE_BUILTIN, IGNORE_BUILTIN, DECLARE_TF, DECLARE_TF,
                DECLARE_ASM, DECLARE_ASM, DECLARE_ASM)
 
 #undef DECLARE_ASM
 #undef DECLARE_TF
 
-  // Note: These are always Code objects, but to conform with
-  // IterateBuiltins() above which assumes Object**'s for the callback
-  // function f, we use an Object* array here.
-  Object* builtins_[builtin_count];
+  Descriptor builtins_[BUILTIN_COUNT];
   bool initialized_;
 
   friend class Isolate;
 
   DISALLOW_COPY_AND_ASSIGN(Builtins);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_BUILTINS_BUILTINS_H_