Implement bitmap descriptor based marking for Boehm GC.

2000-09-30  Hans Boehm  <boehm@acm.org>
	    Bryce McKinlay  <bryce@albatross.co.nz>

	Implement bitmap descriptor based marking for Boehm GC.

	* configure.in: Define JC1GCSPEC. Set it if boehm-gc is used.
	* configure: Rebuilt.
	* libgcj.spec.in: Pass JC1GCSPEC to jc1.
	* include/jvm.h (struct _Jv_VTable): New field `gc_descr'. New inline
	method get_finalizer().
	(struct _Jv_ArrayVTable): Ditto. Declare method array with
	NUM_OBJECT_METHODS elements instead of NUM_OBJECT_METHODS + 1.
	(_Jv_AllocObj): Add new jclass parameter.
	(_Jv_AllocArray): Ditto.
	(_Jv_BuildGCDescr): New prototype.
	* prims.cc (_Jv_AllocObject): Rename parameter `c' to `klass'. Pass
	`klass' to _Jv_AllocObj. Don't set the new object's vtable. Use
	get_finalizer() instead of direct finalizer vtable offset.
	(_Jv_NewObjectArray): Rename parameter `clas' to `klass'. Pass
	`klass' to _Jv_AllocArray. Don't set the new array's vtable.
	(_Jv_NewPrimArray): Call _Jv_FindArrayClass before _Jv_AllocObj.
	Pass `klass' to _Jv_AllocObj. Don't set the new array's vtable.
	* resolve.cc (METHOD_NOT_THERE, METHOD_INACCESSIBLE): New #defines.
	(_Jv_ResolvePoolEntry): Use METHOD_NOT_THERE and METHOD_INACCESSIBLE.
	(_Jv_DetermineVTableIndex): Ditto.
	(_Jv_PrepareClass): Ditto. Remove offset-by-one adjustments from vtable
	calculations to account for new gc_descr field.
	* boehm.cc: #include gc_gcj.h.
	(obj_kind_x, obj_free_list): `#if 0'-ed away.
	(_Jv_MarkObj): Check that vtable doesn't point to a cleared object.
	New commentary from HB. Mark the classes vtable.
	(_Jv_MarkArray): Check that vtable doesn't point to a cleared object.
	(GC_DEFAULT_DESCR): New #define.
	(_Jv_BuildGCDescr): New function. Use GC_DEFAULT_DESCR, for now.
	(_Jv_AllocObj): New parameter `klass'. Use GC_GCJ_MALLOC ().
	(_Jv_AllocArray): New parameter `klass'. Allocate with GC_MALLOC and
	scan conservativly if size is less than min_heap_addr. Set vtable
	pointer of new object before returning.
	(_Jv_AllocBytes): Use GC_MALLOC_ATOMIC, not GC_GENERIC_MALLOC.
	(_Jv_InitGC): Call GC_init_gcj_malloc(). Don't set up marking and
	allocation for obj_kind_x.
	* nogc.cc (_Jv_BuildGCDescr): New function. Return 0.
	(_Jv_AllocObj): Set vtable on returned object.
	(_Jv_AllocArray): Ditto.
	* java/lang/Class.h (_Jv_NewObjectArray): No longer a friend.
	(_Jv_NewPrimArray): Ditto.
	(_Jv_AllocObj): Declare as a friend.
	(_Jv_AllocArray): Ditto.
	* java/lang/natClassLoader.cc (_Jv_FindArrayClass): Copy gc_descr
	from &ObjectClass into new array class. Remove offset-by-one
	adjustments from `method' size calculations to account for gc_descr
	field.

Co-Authored-By: Bryce McKinlay <bryce@albatross.co.nz>

From-SVN: r36679

1 files changed, 11 insertions, 4 deletions

diff --git a/libjava/include/jvm.h b/libjava/include/jvm.h
index e6e6fa6..8d93ed5 100644
--- a/libjava/include/jvm.h
+++ b/libjava/include/jvm.h
@@ -31,7 +31,9 @@ details.  */
 struct _Jv_VTable
 {
   jclass clas;
+  void *gc_descr;
   void *method[1];
+  void *get_finalizer() { return method[0]; }
 };
 
 // Number of virtual methods on object.  FIXME: it sucks that we have
@@ -42,8 +44,9 @@ struct _Jv_VTable
 struct _Jv_ArrayVTable
 {
   jclass clas;
-  // `+1' because there is an extra slot for C++ RTTI compatibility.
-  void *method[NUM_OBJECT_METHODS + 1];
+  void *gc_descr;
+  void *method[NUM_OBJECT_METHODS];
+  void *get_finalizer() { return method[0]; }
 };
 
 union _Jv_word
@@ -106,15 +109,19 @@ extern java::lang::Class StringClass;
 typedef void _Jv_FinalizerFunc (jobject);
 
 /* Allocate space for a new Java object.  */
-void *_Jv_AllocObj (jsize size) __attribute__((__malloc__));
+void *_Jv_AllocObj (jsize size, jclass cl) __attribute__((__malloc__));
 /* Allocate space for an array of Java objects.  */
-void *_Jv_AllocArray (jsize size) __attribute__((__malloc__));
+void *_Jv_AllocArray (jsize size, jclass cl) __attribute__((__malloc__));
 /* Allocate space that is known to be pointer-free.  */
 void *_Jv_AllocBytes (jsize size) __attribute__((__malloc__));
 /* Initialize the GC.  */
 void _Jv_InitGC (void);
 /* Register a finalizer.  */
 void _Jv_RegisterFinalizer (void *object, _Jv_FinalizerFunc *method);
+/* Compute the GC descriptor for a class */
+#ifdef INTERPRETER
+void * _Jv_BuildGCDescr(jclass);
+#endif
 
 /* Allocate some unscanned, unmoveable memory.  Return NULL if out of
    memory.  */