* Move almost all roots into an array ready for use by a constant-pool...

src/heap.h

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 16 matching lines @@
 
 #ifndef V8_HEAP_H_
 #define V8_HEAP_H_
 
 #include "zone-inl.h"
 
 namespace v8 {
 namespace internal {
 
 // Defines all the roots in Heap.
-#define STRONG_ROOT_LIST(V)                             \
-  V(Map, meta_map)                                      \
-  V(Map, heap_number_map)                               \
-  V(Map, short_string_map)                              \
-  V(Map, medium_string_map)                             \
-  V(Map, long_string_map)                               \
-  V(Map, short_ascii_string_map)                        \
-  V(Map, medium_ascii_string_map)                       \
-  V(Map, long_ascii_string_map)                         \
-  V(Map, short_symbol_map)                              \
-  V(Map, medium_symbol_map)                             \
-  V(Map, long_symbol_map)                               \
-  V(Map, short_ascii_symbol_map)                        \
-  V(Map, medium_ascii_symbol_map)                       \
-  V(Map, long_ascii_symbol_map)                         \
-  V(Map, short_cons_symbol_map)                         \
-  V(Map, medium_cons_symbol_map)                        \
-  V(Map, long_cons_symbol_map)                          \
-  V(Map, short_cons_ascii_symbol_map)                   \
-  V(Map, medium_cons_ascii_symbol_map)                  \
-  V(Map, long_cons_ascii_symbol_map)                    \
-  V(Map, short_sliced_symbol_map)                       \
-  V(Map, medium_sliced_symbol_map)                      \
-  V(Map, long_sliced_symbol_map)                        \
-  V(Map, short_sliced_ascii_symbol_map)                 \
-  V(Map, medium_sliced_ascii_symbol_map)                \
-  V(Map, long_sliced_ascii_symbol_map)                  \
-  V(Map, short_external_symbol_map)                     \
-  V(Map, medium_external_symbol_map)                    \
-  V(Map, long_external_symbol_map)                      \
-  V(Map, short_external_ascii_symbol_map)               \
-  V(Map, medium_external_ascii_symbol_map)              \
-  V(Map, long_external_ascii_symbol_map)                \
-  V(Map, short_cons_string_map)                         \
-  V(Map, medium_cons_string_map)                        \
-  V(Map, long_cons_string_map)                          \
-  V(Map, short_cons_ascii_string_map)                   \
-  V(Map, medium_cons_ascii_string_map)                  \
-  V(Map, long_cons_ascii_string_map)                    \
-  V(Map, short_sliced_string_map)                       \
-  V(Map, medium_sliced_string_map)                      \
-  V(Map, long_sliced_string_map)                        \
-  V(Map, short_sliced_ascii_string_map)                 \
-  V(Map, medium_sliced_ascii_string_map)                \
-  V(Map, long_sliced_ascii_string_map)                  \
-  V(Map, short_external_string_map)                     \
-  V(Map, medium_external_string_map)                    \
-  V(Map, long_external_string_map)                      \
-  V(Map, short_external_ascii_string_map)               \
-  V(Map, medium_external_ascii_string_map)              \
-  V(Map, long_external_ascii_string_map)                \
-  V(Map, undetectable_short_string_map)                 \
-  V(Map, undetectable_medium_string_map)                \
-  V(Map, undetectable_long_string_map)                  \
-  V(Map, undetectable_short_ascii_string_map)           \
-  V(Map, undetectable_medium_ascii_string_map)          \
-  V(Map, undetectable_long_ascii_string_map)            \
-  V(Map, byte_array_map)                                \
-  V(Map, fixed_array_map)                               \
-  V(Map, hash_table_map)                                \
-  V(Map, context_map)                                   \
-  V(Map, catch_context_map)                             \
-  V(Map, global_context_map)                            \
-  V(Map, code_map)                                      \
-  V(Map, oddball_map)                                   \
-  V(Map, global_property_cell_map)                      \
-  V(Map, boilerplate_function_map)                      \
-  V(Map, shared_function_info_map)                      \
-  V(Map, proxy_map)                                     \
-  V(Map, one_word_filler_map)                           \
-  V(Map, two_word_filler_map)                           \
-  V(Object, nan_value)                                  \
-  V(Object, undefined_value)                            \
-  V(Object, minus_zero_value)                           \
-  V(Object, null_value)                                 \
-  V(Object, true_value)                                 \
-  V(Object, false_value)                                \
-  V(String, empty_string)                               \
-  V(FixedArray, empty_fixed_array)                      \
-  V(DescriptorArray, empty_descriptor_array)            \
-  V(Object, the_hole_value)                             \
-  V(Map, neander_map)                                   \
-  V(JSObject, message_listeners)                        \
-  V(Proxy, prototype_accessors)                         \
-  V(NumberDictionary, code_stubs)                       \
-  V(NumberDictionary, non_monomorphic_cache)            \
-  V(Code, js_entry_code)                                \
-  V(Code, js_construct_entry_code)                      \
-  V(Code, c_entry_code)                                 \
-  V(Code, c_entry_debug_break_code)                     \
-  V(FixedArray, number_string_cache)                    \
-  V(FixedArray, single_character_string_cache)          \
-  V(FixedArray, natives_source_cache)                   \
-  V(Object, last_script_id)
+#define STRONG_ROOT_LIST(V)                                                    \
+  V(Map, meta_map, MetaMap)                                                    \

[Kasper Lund, 2009/07/08 12:42:37]

Is it really worth giving everything two names to comply with the style guide
for the index constant? I think I'd prefer just having one name...

[Erik Corry, 2009/07/08 14:19:50]

I think I'll stick with both names because the camel case names will be natural
to use in the ARM code generator.

+  V(Map, heap_number_map, HeapNumberMap)                                       \
+  V(Map, short_string_map, ShortStringMap)                                     \
+  V(Map, medium_string_map, MediumStringMap)                                   \
+  V(Map, long_string_map, LongStringMap)                                       \
+  V(Map, short_ascii_string_map, ShortAsciiStringMap)                          \
+  V(Map, medium_ascii_string_map, MediumAsciiStringMap)                        \
+  V(Map, long_ascii_string_map, LongAsciiStringMap)                            \
+  V(Map, short_symbol_map, ShortSymbolMap)                                     \
+  V(Map, medium_symbol_map, MediumSymbolMap)                                   \
+  V(Map, long_symbol_map, LongSymbolMap)                                       \
+  V(Map, short_ascii_symbol_map, ShortAsciiSymbolMap)                          \
+  V(Map, medium_ascii_symbol_map, MediumAsciiSymbolMap)                        \
+  V(Map, long_ascii_symbol_map, LongAsciiSymbolMap)                            \
+  V(Map, short_cons_symbol_map, ShortConsSymbolMap)                            \
+  V(Map, medium_cons_symbol_map, MediumConsSymbolMap)                          \
+  V(Map, long_cons_symbol_map, LongConsSymbolMap)                              \
+  V(Map, short_cons_ascii_symbol_map, ShortConsAsciiSymbolMap)                 \
+  V(Map, medium_cons_ascii_symbol_map, MediumConsAsciiSymbolMap)               \
+  V(Map, long_cons_ascii_symbol_map, LongConsAsciiSymbolMap)                   \
+  V(Map, short_sliced_symbol_map, ShortSlicedSymbolMap)                        \
+  V(Map, medium_sliced_symbol_map, MediumSlicedSymbolMap)                      \
+  V(Map, long_sliced_symbol_map, LongSlicedSymbolMap)                          \
+  V(Map, short_sliced_ascii_symbol_map, ShortSlicedAsciiSymbolMap)             \
+  V(Map, medium_sliced_ascii_symbol_map, MediumSlicedAsciiSymbolMap)           \
+  V(Map, long_sliced_ascii_symbol_map, LongSlicedAsciiSymbolMap)               \
+  V(Map, short_external_symbol_map, ShortExternalSymbolMap)                    \
+  V(Map, medium_external_symbol_map, MediumExternalSymbolMap)                  \
+  V(Map, long_external_symbol_map, LongExternalSymbolMap)                      \
+  V(Map, short_external_ascii_symbol_map, ShortExternalAsciiSymbolMap)         \
+  V(Map, medium_external_ascii_symbol_map, MediumExternalAsciiSymbolMap)       \
+  V(Map, long_external_ascii_symbol_map, LongExternalAsciiSymbolMap)           \
+  V(Map, short_cons_string_map, ShortConsStringMap)                            \
+  V(Map, medium_cons_string_map, MediumConsStringMap)                          \
+  V(Map, long_cons_string_map, LongConsStringMap)                              \
+  V(Map, short_cons_ascii_string_map, ShortConsAsciiStringMap)                 \
+  V(Map, medium_cons_ascii_string_map, MediumConsAsciiStringMap)               \
+  V(Map, long_cons_ascii_string_map, LongConsAsciiStringMap)                   \
+  V(Map, short_sliced_string_map, ShortSlicedStringMap)                        \
+  V(Map, medium_sliced_string_map, MediumSlicedStringMap)                      \
+  V(Map, long_sliced_string_map, LongSlicedStringMap)                          \
+  V(Map, short_sliced_ascii_string_map, ShortSlicedAsciiStringMap)             \
+  V(Map, medium_sliced_ascii_string_map, MediumSlicedAsciiStringMap)           \
+  V(Map, long_sliced_ascii_string_map, LongSlicedAsciiStringMap)               \
+  V(Map, short_external_string_map, ShortExternalStringMap)                    \
+  V(Map, medium_external_string_map, MediumExternalStringMap)                  \
+  V(Map, long_external_string_map, LongExternalStringMap)                      \
+  V(Map, short_external_ascii_string_map, ShortExternalAsciiStringMap)         \
+  V(Map, medium_external_ascii_string_map, MediumExternalAsciiStringMap)       \
+  V(Map, long_external_ascii_string_map, LongExternalAsciiStringMap)           \
+  V(Map, undetectable_short_string_map, UndetectableShortStringMap)            \
+  V(Map, undetectable_medium_string_map, UndetectableMediumStringMap)          \
+  V(Map, undetectable_long_string_map, UndetectableLongStringMap)              \
+  V(Map, undetectable_short_ascii_string_map, UndetectableShortAsciiStringMap) \
+  V(Map,                                                                       \
+    undetectable_medium_ascii_string_map,                                      \
+    UndetectableMediumAsciiStringMap)                                          \
+  V(Map, undetectable_long_ascii_string_map, UndetectableLongAsciiStringMap)   \
+  V(Map, byte_array_map, ByteArrayMap)                                         \
+  V(Map, fixed_array_map, FixedArrayMap)                                       \
+  V(Map, hash_table_map, HashTableMap)                                         \
+  V(Map, context_map, ContextMap)                                              \
+  V(Map, catch_context_map, CatchContextMap)                                   \
+  V(Map, global_context_map, GlobalContextMap)                                 \
+  V(Map, code_map, CodeMap)                                                    \
+  V(Map, oddball_map, OddballMap)                                              \
+  V(Map, global_property_cell_map, GlobalPropertyCellMap)                      \
+  V(Map, boilerplate_function_map, BoilerplateFunctionMap)                     \
+  V(Map, shared_function_info_map, SharedFunctionInfoMap)                      \
+  V(Map, proxy_map, ProxyMap)                                                  \
+  V(Map, one_word_filler_map, OneWordFillerMap)                                \
+  V(Map, two_word_filler_map, TwoWordFillerMap)                                \
+  V(Object, nan_value, NanValue)                                               \
+  V(Object, undefined_value, UndefinedValue)                                   \
+  V(Object, minus_zero_value, MinusZeroValue)                                  \
+  V(Object, null_value, NullValue)                                             \
+  V(Object, true_value, TrueValue)                                             \
+  V(Object, false_value, FalseValue)                                           \
+  V(String, empty_string, EmptyString)                                         \
+  V(FixedArray, empty_fixed_array, EmptyFixedArray)                            \
+  V(DescriptorArray, empty_descriptor_array, EmptyDescriptorArray)             \
+  V(Object, the_hole_value, TheHoleValue)                                      \
+  V(Map, neander_map, NeanderMap)                                              \
+  V(JSObject, message_listeners, MessageListeners)                             \
+  V(Proxy, prototype_accessors, PrototypeAccessors)                            \
+  V(NumberDictionary, code_stubs, CodeStubs)                                   \
+  V(NumberDictionary, non_monomorphic_cache, NonMonomorphicCache)              \
+  V(Code, js_entry_code, JsEntryCode)                                          \
+  V(Code, js_construct_entry_code, JsConstructEntryCode)                       \
+  V(Code, c_entry_code, CEntryCode)                                            \
+  V(Code, c_entry_debug_break_code, CEntryDebugBreakCode)                      \
+  V(FixedArray, number_string_cache, NumberStringCache)                        \
+  V(FixedArray, single_character_string_cache, SingleCharacterStringCache)     \
+  V(FixedArray, natives_source_cache, NativesSourceCache)                      \
+  V(Object, last_script_id, LastScriptId)
 
 
 #define ROOT_LIST(V)                                  \
   STRONG_ROOT_LIST(V)                                 \
-  V(Object, symbol_table)
+  V(Object, symbol_table, SymbolTable)

[Kasper Lund, 2009/07/08 12:42:37]

Why isn't this of type SymbolTable*?

[Erik Corry, 2009/07/08 14:19:50]

It is now.

 
 #define SYMBOL_LIST(V)                                                   \
   V(Array_symbol, "Array")                                               \
   V(Object_symbol, "Object")                                             \
   V(Proto_symbol, "__proto__")                                           \
   V(StringImpl_symbol, "StringImpl")                                     \
   V(arguments_symbol, "arguments")                                       \
   V(Arguments_symbol, "Arguments")                                       \
   V(arguments_shadow_symbol, ".arguments")                               \
   V(call_symbol, "call")                                                 \
@@ skipping 483 matching lines @@
   static bool GarbageCollectionGreedyCheck();
 #endif
 
   static void SetGlobalGCPrologueCallback(GCCallback callback) {
     global_gc_prologue_callback_ = callback;
   }
   static void SetGlobalGCEpilogueCallback(GCCallback callback) {
     global_gc_epilogue_callback_ = callback;
   }
 
-  // Heap roots
-#define ROOT_ACCESSOR(type, name) static type* name() { return name##_; }
+  // Heap roots.  We have versions with and without type::cast() here.  You
+  // can't use type::cast during GC because the assert fails.
+#define ROOT_ACCESSOR(type, name, camel_name)                                  \
+  static inline type* name() {                                                 \
+    return type::cast(roots_[k##camel_name##RootIndex]);                       \
+  }                                                                            \
+  static inline type* raw_unchecked_##name() {                                 \
+    return reinterpret_cast<type*>(roots_[k##camel_name##RootIndex]);          \
+  }
   ROOT_LIST(ROOT_ACCESSOR)
 #undef ROOT_ACCESSOR
 
 // Utility type maps
-#define STRUCT_MAP_ACCESSOR(NAME, Name, name) \
-    static Map* name##_map() { return name##_map_; }
+#define STRUCT_MAP_ACCESSOR(NAME, Name, name)                                  \
+    static inline Map* name##_map() {                                          \
+      return Map::cast(roots_[k##Name##MapRootIndex]);                         \
+    }
   STRUCT_LIST(STRUCT_MAP_ACCESSOR)
 #undef STRUCT_MAP_ACCESSOR
 
-#define SYMBOL_ACCESSOR(name, str) static String* name() { return name##_; }
+#define SYMBOL_ACCESSOR(name, str) static inline String* name() {              \
+    return String::cast(roots_[k##name##RootIndex]);                           \
+  }
   SYMBOL_LIST(SYMBOL_ACCESSOR)
 #undef SYMBOL_ACCESSOR
 
   // The hidden_symbol is special because it is the empty string, but does
   // not match the empty string.
   static String* hidden_symbol() { return hidden_symbol_; }
 
   // Iterates over all roots in the heap.
   static void IterateRoots(ObjectVisitor* v);
   // Iterates over all strong roots in the heap.
@@ skipping 24 matching lines @@
   // Checks whether an address/object in a space.
   // Currently used by tests and heap verification only.
   static bool InSpace(Address addr, AllocationSpace space);
   static bool InSpace(HeapObject* value, AllocationSpace space);
 
   // Finds out which space an object should get promoted to based on its type.
   static inline OldSpace* TargetSpace(HeapObject* object);
   static inline AllocationSpace TargetSpaceId(InstanceType type);
 
   // Sets the stub_cache_ (only used when expanding the dictionary).
-  static void set_code_stubs(NumberDictionary* value) { code_stubs_ = value; }
+  static void set_code_stubs(NumberDictionary* value) {
+    roots_[kCodeStubsRootIndex] = value;
+  }
 
   // Sets the non_monomorphic_cache_ (only used when expanding the dictionary).
   static void set_non_monomorphic_cache(NumberDictionary* value) {
-    non_monomorphic_cache_ = value;
+    roots_[kNonMonomorphicCacheRootIndex] = value;
   }
 
   // Update the next script id.
   static inline void SetLastScriptId(Object* last_script_id);
 
 #ifdef DEBUG
   static void Print();
   static void PrintHandles();
 
   // Verify the heap is in its normal state before or after a GC.
@@ skipping 166 matching lines @@
   // by global handles
   static int amount_of_external_allocated_memory_;
 
   // Caches the amount of external memory registered at the last global gc.
   static int amount_of_external_allocated_memory_at_last_global_gc_;
 
   // Indicates that an allocation has failed in the old generation since the
   // last GC.
   static int old_gen_exhausted_;
 
-  // Declare all the roots
-#define ROOT_DECLARATION(type, name) static type* name##_;
-  ROOT_LIST(ROOT_DECLARATION)
-#undef ROOT_DECLARATION
+  // Declare all the root indices.
+  enum RootListIndex {
+#define ROOT_INDEX_DECLARATION(type, name, camel_name) k##camel_name##RootIndex,
+    STRONG_ROOT_LIST(ROOT_INDEX_DECLARATION)
+#undef ROOT_INDEX_DECLARATION
 
 // Utility type maps
-#define DECLARE_STRUCT_MAP(NAME, Name, name) static Map* name##_map_;
+#define DECLARE_STRUCT_MAP(NAME, Name, name) k##Name##MapRootIndex,
   STRUCT_LIST(DECLARE_STRUCT_MAP)
 #undef DECLARE_STRUCT_MAP
 
-#define SYMBOL_DECLARATION(name, str) static String* name##_;
-  SYMBOL_LIST(SYMBOL_DECLARATION)
+#define SYMBOL_INDEX_DECLARATION(name, str) k##name##RootIndex,
+    SYMBOL_LIST(SYMBOL_INDEX_DECLARATION)
 #undef SYMBOL_DECLARATION
 
+    kSymbolTableRootIndex,
+    kStrongRootListLength = kSymbolTableRootIndex,
+    kRootListLength};

[Kasper Lund, 2009/07/08 12:42:37]

Put }; on a new line.

[Erik Corry, 2009/07/08 14:19:50]

OK

+
+  static Object* roots_[kRootListLength];
+
+  struct StringTypeTable {
+    InstanceType type;
+    int size;
+    RootListIndex index;
+  };
+
+  struct ConstantSymbolTable {
+    const char* contents;
+    RootListIndex index;
+  };
+
+  struct StructTable {
+    InstanceType type;
+    int size;
+    RootListIndex index;
+  };
+
+  static const StringTypeTable string_type_table[];
+  static const ConstantSymbolTable constant_symbol_table[];
+  static const StructTable struct_table[];
+
   // The special hidden symbol which is an empty string, but does not match
   // any string when looked up in properties.
   static String* hidden_symbol_;
 
   // GC callback function, called before and after mark-compact GC.
   // Allocations in the callback function are disallowed.
   static GCCallback global_gc_prologue_callback_;
   static GCCallback global_gc_epilogue_callback_;
 
   // Checks whether a global GC is necessary
@@ skipping 493 matching lines @@
   int marked_count_;
 
   // The count from the end of the previous full GC.  Will be zero if there
   // was no previous full GC.
   int previous_marked_count_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_HEAP_H_