dvander@11: /*
dvander@11:  * Copyright (C) 2012 David Anderson
dvander@11:  *
dvander@11:  * This file is part of JITCraft.
dvander@11:  *
dvander@11:  * JITCraft is free software: you can redistribute it and/or modify it under
dvander@11:  * the terms of the GNU General Public License as published by the Free
dvander@11:  * Software Foundation, either version 3 of the License, or (at your option)
dvander@11:  * any later version.
dvander@11:  * 
dvander@11:  * Foobar is distributed in the hope that it will be useful, but WITHOUT ANY
dvander@11:  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
dvander@11:  * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
dvander@11:  *
dvander@11:  * You should have received a copy of the GNU General Public License along with
dvander@11:  * JITCraft. If not, see http://www.gnu.org/licenses/.
dvander@11:  */
dvander@11: #ifndef _include_jitcraft_objects_h_
dvander@11: #define _include_jitcraft_objects_h_
dvander@11: 
dvander@11: #include "Utility.h"
dvander@11: #include "Spaces.h"
dvander@13: #include "Barriers.h"
dvander@11: 
dvander@11: namespace jc {
dvander@11: 
dvander@11: class Zone;
dvander@11: 
dvander@11: // Macros for laying out objects.
dvander@11: #define OBJECT_FIELD(Type, name)                    \
dvander@11:     Type fld_##name##_;
dvander@11: 
dvander@12: // :TODO: refactor these now that objects are no longer tagged.
dvander@11: #define RAW_FIELD_ADDRESS(ptr)                      \
dvander@12:     (reinterpret_cast<uintptr_t>(ptr))
dvander@11: #define TYPED_FIELD_ADDRESS(Type, ptr)              \
dvander@11:     (reinterpret_cast<Type *>(RAW_FIELD_ADDRESS(ptr)))
dvander@11: #define OBJ_FIELD_OFFSET(obj, ptr)                  \
dvander@11:     (reinterpret_cast<uintptr_t>(ptr) - reinterpret_cast<uintptr_t>(obj))
dvander@11: #define READ_FIELD(name)                            \
dvander@11:     read(&fld_##name##_)
dvander@11: #define WRITE_FIELD(name, val)                      \
dvander@11:     write(&fld_##name##_, val)
dvander@11: #define READ_FIELD_OBJ(name)                        \
dvander@11:     read(reinterpret_cast<Object **>(&fld_##name##_))
dvander@11: #define WRITE_FIELD_OBJ(env, name, val)             \
dvander@11:     write(env, reinterpret_cast<Object **>(&fld_##name##_), val)
dvander@11: #define WRITE_FIELD_OBJ_NO_BARRIER(name, val)  \
dvander@11:     writeNoBarrier(reinterpret_cast<Object **>(&fld_##name##_), val)
dvander@11: 
dvander@11: // Garbage-collection objects require a header to describe their layout. This
dvander@11: // header is called a "map". The different kinds of maps are enumerated below.
dvander@11: class Map;
dvander@11: 
dvander@11: enum MapKind
dvander@11: {
dvander@12:     // Represents Type objects.
dvander@12:     MapKind_Type,
dvander@12: 
dvander@14:     // Represents basic data structures. When adding to this, don't forget
dvander@14:     // to update Zone::initialize(), or you'll get a NULL crash trying to
dvander@14:     // allocate, since these maps are cached.
dvander@12:     MapKind_FixedArray,
dvander@12:     MapKind_ByteArray,
dvander@12:     MapKind_Code,
dvander@14:     MapKind_Reference,
dvander@14:     MapKind_Module,
dvander@26:     MapKind_Function,
dvander@11: 
dvander@14:     // Used to represent Arrays. This does not have a canonical map.
dvander@12:     MapKind_Array,
dvander@12: 
dvander@12:     // These represent special Map subclasses that require special tracing.
dvander@12:     MapKinds_Special,
dvander@12:     MapKind_Meta,           // (default map class)
dvander@12:     MapKind_MetaArray,      // ArrayMap instances
dvander@12:     MapKinds_EndSpecial,
dvander@11: 
dvander@11:     MapKinds_Total
dvander@11: };
dvander@11: 
dvander@12: typedef void * VoidPtr;
dvander@11: 
dvander@11: // All garbage collected objects must inherit from GCObject. Note that using
dvander@11: // virtual functions is illegal, as the |map| field would be displaced.
dvander@12: class Object
dvander@11: {
dvander@13:     Barriered<Map> map_;
dvander@11: 
dvander@11:   public:
dvander@11:     void init(Map *map) {
dvander@13:         map_ = map;
dvander@11:     }
dvander@11: 
dvander@11:     Map *map() {
dvander@13:         return map_;
dvander@11:     }
dvander@12:     inline bool is(MapKind map);
dvander@13: 
dvander@13:     inline void write(Zone *zone, Object **ptr, Object *value);
dvander@11: };
dvander@11: 
dvander@12: // Maps describe the layout of GCObjects. Every GCObject requires a map.
dvander@12: class Map : public Object
dvander@11: {
dvander@13:     MapKind kind_;
dvander@11: 
dvander@11:   public:
dvander@11:     void setKind(MapKind kind) {
dvander@13:         kind_ = kind;
dvander@11:     }
dvander@11:     MapKind kind() {
dvander@13:         return kind_;
dvander@11:     }
dvander@12: 
dvander@12:     static inline Map *cast(Object *obj) {
dvander@12:         // Note that ArrayMap is a map, but a special one: since it is non-
dvander@12:         assert(obj->map()->kind() > MapKinds_Special &&
dvander@12:                obj->map()->kind() < MapKinds_EndSpecial);
dvander@12:         return reinterpret_cast<Map *>(obj);
dvander@12:     }
dvander@11: };
dvander@11: 
dvander@11: // Heap-allocated objects go here. Heaps are thread-local.
dvander@11: class Heap
dvander@11: {
dvander@11:     Zone *zone_;
dvander@12:     HeapStack lifoSpace_;
dvander@11:     OldSpace mapSpace_;
dvander@11:     OldSpace oldSpace_;
dvander@11: 
dvander@11:     Map *metaMap_;
dvander@11: 
dvander@11:   public:
dvander@11:     enum Tenure {
dvander@12:         // Default, objects go into the nursery.
dvander@11:         Tenure_Default,
dvander@12:         
dvander@12:         // If objects are proven to not escape the stack, they can go into
dvander@12:         // a LIFO arena. Allocation on the LIFO arena is not guaranteed to
dvander@12:         // succeed; thus, objects may still be allocated in other arenas.
dvander@12:         Tenure_Stack,
dvander@12: 
dvander@12:         // Objects that should not go into the nursery (i.e. are expected
dvander@12:         // to be long-living) go here.
dvander@11:         Tenure_Old
dvander@11:     };
dvander@11: 
dvander@11:   private:
dvander@12:     Address newOldObject(size_t bytes);
dvander@12:     inline Address newStackObject(size_t bytes);
dvander@11:     inline Address newObject(size_t bytes, Tenure pretenure);
dvander@11: 
dvander@11:   public:
dvander@11:     Heap(Zone *zone);
dvander@11:     bool initialize();
dvander@11: 
dvander@11:     inline Object *allocate(Map *map, size_t byes, Tenure pretenure);
dvander@27:     inline Object *allocate(Handle<Map> map, size_t byes, Tenure pretenure);
dvander@11:     Map *allocateMap(MapKind kind, size_t bytes);
dvander@11: 
dvander@11:     Map *metaMap() {
dvander@11:         return metaMap_;
dvander@11:     }
dvander@12:     inline Address lifoPosition() const {
dvander@12:         return lifoSpace_.position();
dvander@12:     }
dvander@12:     inline void unwindLifo(Address to) {
dvander@12:         lifoSpace_.unwind(to);
dvander@12:     }
dvander@11: };
dvander@11: 
dvander@11: inline bool
dvander@11: Object::is(MapKind kind)
dvander@11: {
dvander@12:     return map()->kind() == kind;
dvander@11: }
dvander@11: 
dvander@11: }
dvander@11: 
dvander@11: #endif //_include_jitcraft_objects_h_