// boehm.cc - interface between libjava and Boehm GC.
-/* Copyright (C) 1998, 1999 Cygnus Solutions
+/* Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
+ Free Software Foundation
This file is part of libgcj.
#include <config.h>
#include <stdio.h>
+#include <limits.h>
-#include <cni.h>
-#include <java/lang/Class.h>
#include <jvm.h>
-#include <java-field.h>
+#include <gcj/cni.h>
+
+#include <java/lang/Class.h>
+#include <java/lang/reflect/Modifier.h>
+#include <java-interp.h>
+
+// More nastiness: the GC wants to define TRUE and FALSE. We don't
+// need the Java definitions (themselves a hack), so we undefine them.
+#undef TRUE
+#undef FALSE
+
+// We include two autoconf headers. Avoid multiple definition warnings.
+#undef PACKAGE_NAME
+#undef PACKAGE_STRING
+#undef PACKAGE_TARNAME
+#undef PACKAGE_VERSION
+
+#ifdef HAVE_DLFCN_H
+#undef _GNU_SOURCE
+#define _GNU_SOURCE
+#include <dlfcn.h>
+#endif
-// We need to include gc_priv.h. However, it tries to include
-// config.h if it hasn't already been included. So we force the
-// inclusion of the Boehm config.h.
extern "C"
{
-#include <boehm-config.h>
-#include <gc_priv.h>
-#include <gc_mark.h>
-
- // These aren't declared in any Boehm GC header.
- void GC_finalize_all (void);
- ptr_t GC_debug_generic_malloc (size_t size, int k, GC_EXTRA_PARAMS);
-};
+#include <gc_config.h>
-// FIXME: this should probably be defined in some GC header.
-#ifdef GC_DEBUG
-# define GC_GENERIC_MALLOC(Size, Type) \
- GC_debug_generic_malloc (Size, Type, GC_EXTRAS)
-#else
-# define GC_GENERIC_MALLOC(Size, Type) GC_generic_malloc (Size, Type)
+// Set GC_DEBUG before including gc.h!
+#ifdef LIBGCJ_GC_DEBUG
+# define GC_DEBUG
#endif
-// We must check for plausibility ourselves.
-#define MAYBE_MARK(Obj, Top, Limit, Source, Exit) \
- if ((ptr_t) (Obj) >= GC_least_plausible_heap_addr \
- && (ptr_t) (Obj) <= GC_greatest_plausible_heap_addr) \
- PUSH_CONTENTS (Obj, Top, Limit, Source, Exit)
-
-#define ObjectClass _CL_Q34java4lang6Object
-extern java::lang::Class ObjectClass;
-#define ClassClass _CL_Q34java4lang5Class
-extern java::lang::Class ClassClass;
+#include <gc_mark.h>
+#include <gc_gcj.h>
+#include <javaxfc.h> // GC_finalize_all declaration.
-\f
+#ifdef THREAD_LOCAL_ALLOC
+# define GC_REDIRECT_TO_LOCAL
+# include <gc_local_alloc.h>
+#endif
-// Nonzero if this module has been initialized.
-static int initialized = 0;
+ // From boehm's misc.c
+ void GC_enable();
+ void GC_disable();
+};
-// `kind' index used when allocating Java objects.
-static int obj_kind_x;
+#define MAYBE_MARK(Obj, Top, Limit, Source) \
+ Top=GC_MARK_AND_PUSH((GC_PTR) Obj, Top, Limit, (GC_PTR *) Source)
// `kind' index used when allocating Java arrays.
static int array_kind_x;
-// Freelist used for Java objects.
-static ptr_t *obj_free_list;
-
// Freelist used for Java arrays.
-static ptr_t *array_free_list;
+static void **array_free_list;
+
+static int _Jv_GC_has_static_roots (const char *filename, void *, size_t);
\f
// object. We use `void *' arguments and return, and not what the
// Boehm GC wants, to avoid pollution in our headers.
void *
-_Jv_MarkObj (void *addr, void *msp, void *msl, void * /*env*/)
+_Jv_MarkObj (void *addr, void *msp, void *msl, void *env)
{
- mse *mark_stack_ptr = (mse *) msp;
- mse *mark_stack_limit = (mse *) msl;
+ struct GC_ms_entry *mark_stack_ptr = (struct GC_ms_entry *)msp;
+ struct GC_ms_entry *mark_stack_limit = (struct GC_ms_entry *)msl;
+
+ if (env == (void *)1) /* Object allocated with debug allocator. */
+ addr = (GC_PTR)GC_USR_PTR_FROM_BASE(addr);
jobject obj = (jobject) addr;
_Jv_VTable *dt = *(_Jv_VTable **) addr;
- // We check this in case a GC occurs before the vtbl is set. FIXME:
- // should use allocation lock while initializing object.
- if (! dt)
+ // The object might not yet have its vtable set, or it might
+ // really be an object on the freelist. In either case, the vtable slot
+ // will either be 0, or it will point to a cleared object.
+ // This assumes Java objects have size at least 3 words,
+ // including the header. But this should remain true, since this
+ // should only be used with debugging allocation or with large objects.
+ if (__builtin_expect (! dt || !(dt -> get_finalizer()), false))
return mark_stack_ptr;
jclass klass = dt->clas;
+ GC_PTR p;
- // Every object has a sync_info pointer.
- word w = (word) obj->sync_info;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, obj, o1label);
- // Mark the object's class.
- w = (word) klass;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, obj, o2label);
+ p = (GC_PTR) dt;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, obj);
- if (klass == &ClassClass)
+# ifndef JV_HASH_SYNCHRONIZATION
+ // Every object has a sync_info pointer.
+ p = (GC_PTR) obj->sync_info;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, obj);
+# endif
+
+ if (__builtin_expect (klass == &java::lang::Class::class$, false))
{
+ // Currently we allocate some of the memory referenced from class objects
+ // as pointerfree memory, and then mark it more intelligently here.
+ // We ensure that the ClassClass mark descriptor forces invocation of
+ // this procedure.
+ // Correctness of this is subtle, but it looks OK to me for now. For the incremental
+ // collector, we need to make sure that the class object is written whenever
+ // any of the subobjects are altered and may need rescanning. This may be tricky
+ // during construction, and this may not be the right way to do this with
+ // incremental collection.
+ // If we overflow the mark stack, we will rescan the class object, so we should
+ // be OK. The same applies if we redo the mark phase because win32 unmapped part
+ // of our root set. - HB
jclass c = (jclass) addr;
- w = (word) c->next;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, c2label);
- w = (word) c->name;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, c3label);
- w = (word) c->superclass;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, c4label);
- for (int i = 0; i < c->constants.size; ++i)
- {
- w = (word) c->constants.data[i];
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, c5label);
- }
+ p = (GC_PTR) c->name;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+ p = (GC_PTR) c->superclass;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+
+ p = (GC_PTR) c->constants.tags;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+ p = (GC_PTR) c->constants.data;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
// If the class is an array, then the methods field holds a
// pointer to the element class. If the class is primitive,
// then the methods field holds a pointer to the array class.
- w = (word) c->methods;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, c6label);
-
- if (! c->isArray() && ! c->isPrimitive())
- {
- // Scan each method in the cases where `methods' really
- // points to a methods structure.
- for (int i = 0; i < c->method_count; ++i)
- {
- w = (word) c->methods[i].name;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c,
- cm1label);
- w = (word) c->methods[i].signature;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c,
- cm2label);
- // FIXME: `ncode' entry?
- }
- }
-
- // Mark all the fields.
- w = (word) c->fields;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, c8label);
- for (int i = 0; i < c->field_count; ++i)
- {
-#ifndef COMPACT_FIELDS
- w = (word) c->fields[i].name;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, c8alabel);
-#endif
- w = (word) c->fields[i].type;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, c8blabel);
- }
-
- w = (word) c->vtable;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, c9label);
- w = (word) c->interfaces;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, cAlabel);
- for (int i = 0; i < c->interface_count; ++i)
- {
- w = (word) c->interfaces[i];
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, cClabel);
- }
- w = (word) c->loader;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, c, cBlabel);
+ p = (GC_PTR) c->methods;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+
+ p = (GC_PTR) c->fields;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+
+ // The vtable might be allocated even for compiled code.
+ p = (GC_PTR) c->vtable;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+
+ p = (GC_PTR) c->interfaces;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+ p = (GC_PTR) c->loader;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+
+ // The dispatch tables can be allocated at runtime.
+ p = (GC_PTR) c->ancestors;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+
+ p = (GC_PTR) c->idt;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+
+ p = (GC_PTR) c->arrayclass;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+ p = (GC_PTR) c->protectionDomain;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+ p = (GC_PTR) c->hack_signers;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+ p = (GC_PTR) c->aux_info;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+
+ p = (GC_PTR) c->reflection_data;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
+
+ // The class chain must be marked for runtime-allocated Classes
+ // loaded by the bootstrap ClassLoader.
+ p = (GC_PTR) c->next_or_version;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, c);
}
else
{
// Note: occasionally `klass' can be null. For instance, this
// can happen if a GC occurs between the point where an object
// is allocated and where the vtbl slot is set.
- while (klass && klass != &ObjectClass)
+ while (klass && klass != &java::lang::Object::class$)
{
jfieldID field = JvGetFirstInstanceField (klass);
jint max = JvNumInstanceFields (klass);
if (JvFieldIsRef (field))
{
jobject val = JvGetObjectField (obj, field);
- w = (word) val;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit,
- obj, elabel);
+ p = (GC_PTR) val;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, obj);
}
- field = field->getNextInstanceField ();
+ field = field->getNextField ();
}
klass = klass->getSuperclass();
}
// array (of objects). We use `void *' arguments and return, and not
// what the Boehm GC wants, to avoid pollution in our headers.
void *
-_Jv_MarkArray (void *addr, void *msp, void *msl, void * /*env*/)
+_Jv_MarkArray (void *addr, void *msp, void *msl, void *env)
{
- mse *mark_stack_ptr = (mse *) msp;
- mse *mark_stack_limit = (mse *) msl;
+ struct GC_ms_entry *mark_stack_ptr = (struct GC_ms_entry *)msp;
+ struct GC_ms_entry *mark_stack_limit = (struct GC_ms_entry *)msl;
+
+ if (env == (void *)1) /* Object allocated with debug allocator. */
+ addr = (void *)GC_USR_PTR_FROM_BASE(addr);
jobjectArray array = (jobjectArray) addr;
_Jv_VTable *dt = *(_Jv_VTable **) addr;
- // We check this in case a GC occurs before the vtbl is set. FIXME:
- // should use allocation lock while initializing object.
- if (! dt)
+ // Assumes size >= 3 words. That's currently true since arrays have
+ // a vtable, sync pointer, and size. If the sync pointer goes away,
+ // we may need to round up the size.
+ if (__builtin_expect (! dt || !(dt -> get_finalizer()), false))
return mark_stack_ptr;
- jclass klass = dt->clas;
+ GC_PTR p;
- // Every object has a sync_info pointer.
- word w = (word) array->sync_info;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, array, e1label);
- // Mark the object's class.
- w = (word) klass;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, obj, o2label);
+ p = (GC_PTR) dt;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, array);
+
+# ifndef JV_HASH_SYNCHRONIZATION
+ // Every object has a sync_info pointer.
+ p = (GC_PTR) array->sync_info;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, array);
+# endif
for (int i = 0; i < JvGetArrayLength (array); ++i)
{
jobject obj = elements (array)[i];
- w = (word) obj;
- MAYBE_MARK (w, mark_stack_ptr, mark_stack_limit, array, e2label);
+ p = (GC_PTR) obj;
+ MAYBE_MARK (p, mark_stack_ptr, mark_stack_limit, array);
}
return mark_stack_ptr;
}
-// Allocate space for a new Java object. FIXME: this might be the
-// wrong interface; we might prefer to pass in the object type as
-// well. It isn't important for this collector, but it might be for
-// other collectors.
+// Generate a GC marking descriptor for a class.
+//
+// We assume that the gcj mark proc has index 0. This is a dubious assumption,
+// since another one could be registered first. But the compiler also
+// knows this, so in that case everything else will break, too.
+#define GCJ_DEFAULT_DESCR GC_MAKE_PROC(GC_GCJ_RESERVED_MARK_PROC_INDEX,0)
+
void *
-_Jv_AllocObj (jsize size)
+_Jv_BuildGCDescr(jclass self)
{
- return GC_GENERIC_MALLOC (size, obj_kind_x);
+ jlong desc = 0;
+ jint bits_per_word = CHAR_BIT * sizeof (void *);
+
+ // Note: for now we only consider a bitmap mark descriptor. We
+ // could also handle the case where the first N fields of a type are
+ // references. However, this is not very likely to be used by many
+ // classes, and it is easier to compute things this way.
+
+ // The vtable pointer.
+ desc |= 1ULL << (bits_per_word - 1);
+#ifndef JV_HASH_SYNCHRONIZATION
+ // The sync_info field.
+ desc |= 1ULL << (bits_per_word - 2);
+#endif
+
+ for (jclass klass = self; klass != NULL; klass = klass->getSuperclass())
+ {
+ jfieldID field = JvGetFirstInstanceField(klass);
+ int count = JvNumInstanceFields(klass);
+
+ for (int i = 0; i < count; ++i)
+ {
+ if (field->isRef())
+ {
+ unsigned int off = field->getOffset();
+ // If we run into a weird situation, we bail.
+ if (off % sizeof (void *) != 0)
+ return (void *) (GCJ_DEFAULT_DESCR);
+ off /= sizeof (void *);
+ // If we find a field outside the range of our bitmap,
+ // fall back to procedure marker. The bottom 2 bits are
+ // reserved.
+ if (off >= (unsigned) bits_per_word - 2)
+ return (void *) (GCJ_DEFAULT_DESCR);
+ desc |= 1ULL << (bits_per_word - off - 1);
+ }
+
+ field = field->getNextField();
+ }
+ }
+
+ // For bitmap mark type, bottom bits are 01.
+ desc |= 1;
+ // Bogus warning avoidance (on many platforms).
+ return (void *) (unsigned long) desc;
}
-// Allocate space for a new Java array. FIXME: again, this might be
-// the wrong interface.
+// Allocate some space that is known to be pointer-free.
void *
-_Jv_AllocArray (jsize size)
+_Jv_AllocBytes (jsize size)
{
- return GC_GENERIC_MALLOC (size, array_kind_x);
+ void *r = GC_MALLOC_ATOMIC (size);
+ // We have to explicitly zero memory here, as the GC doesn't
+ // guarantee that PTRFREE allocations are zeroed. Note that we
+ // don't have to do this for other allocation types because we set
+ // the `ok_init' flag in the type descriptor.
+ memset (r, 0, size);
+ return r;
}
-// Allocate some space that is known to be pointer-free.
+#ifdef LIBGCJ_GC_DEBUG
+
void *
-_Jv_AllocBytes (jsize size)
+_Jv_AllocObj (jsize size, jclass klass)
{
- return GC_GENERIC_MALLOC (size, PTRFREE);
+ return GC_GCJ_MALLOC (size, klass->vtable);
}
+void *
+_Jv_AllocPtrFreeObj (jsize size, jclass klass)
+{
+#ifdef JV_HASH_SYNCHRONIZATION
+ void * obj = GC_MALLOC_ATOMIC(size);
+ *((_Jv_VTable **) obj) = klass->vtable;
+#else
+ void * obj = GC_GCJ_MALLOC(size, klass->vtable);
+#endif
+ return obj;
+}
+
+#endif /* LIBGCJ_GC_DEBUG */
+// In the non-debug case, the above two functions are defined
+// as inline functions in boehm-gc.h. In the debug case we
+// really want to take advantage of the definitions in gc_gcj.h.
+
+// Allocate space for a new Java array.
+// Used only for arrays of objects.
+void *
+_Jv_AllocArray (jsize size, jclass klass)
+{
+ void *obj;
+
+#ifdef LIBGCJ_GC_DEBUG
+ // There isn't much to lose by scanning this conservatively.
+ // If we didn't, the mark proc would have to understand that
+ // it needed to skip the header.
+ obj = GC_MALLOC(size);
+#else
+ const jsize min_heap_addr = 16*1024;
+ // A heuristic. If size is less than this value, the size
+ // stored in the array can't possibly be misinterpreted as
+ // a pointer. Thus we lose nothing by scanning the object
+ // completely conservatively, since no misidentification can
+ // take place.
+
+ if (size < min_heap_addr)
+ obj = GC_MALLOC(size);
+ else
+ obj = GC_generic_malloc (size, array_kind_x);
+#endif
+ *((_Jv_VTable **) obj) = klass->vtable;
+ return obj;
+}
+
+/* Allocate space for a new non-Java object, which does not have the usual
+ Java object header but may contain pointers to other GC'ed objects. */
+void *
+_Jv_AllocRawObj (jsize size)
+{
+ return (void *) GC_MALLOC (size ? size : 1);
+}
+
+#ifdef INTERPRETER
+typedef _Jv_ClosureList *closure_list_pointer;
+
+/* Release closures in a _Jv_ClosureList. */
+static void
+finalize_closure_list (GC_PTR obj, GC_PTR)
+{
+ _Jv_ClosureList **clpp = (_Jv_ClosureList **)obj;
+ _Jv_ClosureList::releaseClosures (clpp);
+}
+
+/* Allocate a double-indirect pointer to a _Jv_ClosureList that will
+ get garbage-collected after this double-indirect pointer becomes
+ unreachable by any other objects, including finalizable ones. */
+_Jv_ClosureList **
+_Jv_ClosureListFinalizer ()
+{
+ _Jv_ClosureList **clpp;
+ clpp = (_Jv_ClosureList **)_Jv_AllocBytes (sizeof (*clpp));
+ GC_REGISTER_FINALIZER_UNREACHABLE (clpp, finalize_closure_list,
+ NULL, NULL, NULL);
+ return clpp;
+}
+#endif // INTERPRETER
+
static void
call_finalizer (GC_PTR obj, GC_PTR client_data)
{
return GC_get_heap_size ();
}
-/* Sum size of each hblk. */
-static void
-sum_blocks (struct hblk *h, word arg)
+long
+_Jv_GCFreeMemory (void)
{
- long *sump = (long *) arg;
- /* This evil computation is from boehm-gc/checksums.c. */
- hdr *hhdr = HDR (h);
- int bytes = WORDS_TO_BYTES (hhdr->hb_sz);
- bytes += HDR_BYTES + HBLKSIZE - 1;
- bytes &= ~ (HBLKSIZE - 1);
- *sump += bytes;
+ return GC_get_free_bytes ();
}
-/* This turns out to be expensive to implement. For now, we don't
- care. We could make it less expensive, perhaps, but that would
- require some changes to the collector. */
-long
-_Jv_GCFreeMemory (void)
+void
+_Jv_GCSetInitialHeapSize (size_t size)
+{
+ size_t current = GC_get_heap_size ();
+ if (size > current)
+ GC_expand_hp (size - current);
+}
+
+void
+_Jv_GCSetMaximumHeapSize (size_t size)
+{
+ GC_set_max_heap_size ((GC_word) size);
+}
+
+int
+_Jv_SetGCFreeSpaceDivisor (int div)
+{
+ return (int)GC_set_free_space_divisor ((GC_word)div);
+}
+
+void
+_Jv_DisableGC (void)
{
- long sum = 0;
- GC_apply_to_all_blocks (sum_blocks, &sum);
- return sum;
+ GC_disable();
+}
+
+void
+_Jv_EnableGC (void)
+{
+ GC_enable();
+}
+
+static void * handle_out_of_memory(size_t)
+{
+ _Jv_ThrowNoMemory();
+}
+
+static void
+gcj_describe_type_fn(void *obj, char *out_buf)
+{
+ _Jv_VTable *dt = *(_Jv_VTable **) obj;
+
+ if (! dt /* Shouldn't happen */)
+ {
+ strcpy(out_buf, "GCJ (bad)");
+ return;
+ }
+ jclass klass = dt->clas;
+ if (!klass /* shouldn't happen */)
+ {
+ strcpy(out_buf, "GCJ (bad)");
+ return;
+ }
+ jstring name = klass -> getName();
+ size_t len = name -> length();
+ if (len >= GC_TYPE_DESCR_LEN) len = GC_TYPE_DESCR_LEN - 1;
+ JvGetStringUTFRegion (name, 0, len, out_buf);
+ out_buf[len] = '\0';
}
void
_Jv_InitGC (void)
{
int proc;
- DCL_LOCK_STATE;
+ static bool gc_initialized;
+
+ if (gc_initialized)
+ return;
+
+ gc_initialized = 1;
+
+ // Ignore pointers that do not point to the start of an object.
+ GC_all_interior_pointers = 0;
+
+#if defined (HAVE_DLFCN_H) && defined (HAVE_DLADDR)
+ // Tell the collector to ask us before scanning DSOs.
+ GC_register_has_static_roots_callback (_Jv_GC_has_static_roots);
+#endif
+
+ // Configure the collector to use the bitmap marking descriptors that we
+ // stash in the class vtable.
+ // We always use mark proc descriptor 0, since the compiler knows
+ // about it.
+ GC_init_gcj_malloc (0, (void *) _Jv_MarkObj);
+
+ // Cause an out of memory error to be thrown from the allocators,
+ // instead of returning 0. This is cheaper than checking on allocation.
+ GC_oom_fn = handle_out_of_memory;
+
+ GC_java_finalization = 1;
+
+ // We use a different mark procedure for object arrays. This code
+ // configures a different object `kind' for object array allocation and
+ // marking.
+ array_free_list = GC_new_free_list();
+ proc = GC_new_proc((GC_mark_proc)_Jv_MarkArray);
+ array_kind_x = GC_new_kind(array_free_list, GC_MAKE_PROC (proc, 0), 0, 1);
+
+ // Arrange to have the GC print Java class names in backtraces, etc.
+ GC_register_describe_type_fn(GC_gcj_kind, gcj_describe_type_fn);
+ GC_register_describe_type_fn(GC_gcj_debug_kind, gcj_describe_type_fn);
+}
+
+#ifdef JV_HASH_SYNCHRONIZATION
+// Allocate an object with a fake vtable pointer, which causes only
+// the first field (beyond the fake vtable pointer) to be traced.
+// Eventually this should probably be generalized.
+
+static _Jv_VTable trace_one_vtable = {
+ 0, // class pointer
+ (void *)(2 * sizeof(void *)),
+ // descriptor; scan 2 words incl. vtable ptr.
+ // Least significant bits must be zero to
+ // identify this as a length descriptor
+ {0} // First method
+};
+
+void *
+_Jv_AllocTraceOne (jsize size /* includes vtable slot */)
+{
+ return GC_GCJ_MALLOC (size, &trace_one_vtable);
+}
+
+// Ditto for two words.
+// the first field (beyond the fake vtable pointer) to be traced.
+// Eventually this should probably be generalized.
+
+static _Jv_VTable trace_two_vtable =
+{
+ 0, // class pointer
+ (void *)(3 * sizeof(void *)),
+ // descriptor; scan 3 words incl. vtable ptr.
+ {0} // First method
+};
+
+void *
+_Jv_AllocTraceTwo (jsize size /* includes vtable slot */)
+{
+ return GC_GCJ_MALLOC (size, &trace_two_vtable);
+}
+
+#endif /* JV_HASH_SYNCHRONIZATION */
+
+void
+_Jv_GCInitializeFinalizers (void (*notifier) (void))
+{
+ GC_finalize_on_demand = 1;
+ GC_finalizer_notifier = notifier;
+}
+
+void
+_Jv_GCRegisterDisappearingLink (jobject *objp)
+{
+ // This test helps to ensure that we meet a precondition of
+ // GC_general_register_disappearing_link, viz. "Obj must be a
+ // pointer to the first word of an object we allocated."
+ if (GC_base(*objp))
+ GC_general_register_disappearing_link ((GC_PTR *) objp, (GC_PTR) *objp);
+}
+
+jboolean
+_Jv_GCCanReclaimSoftReference (jobject)
+{
+ // For now, always reclaim soft references. FIXME.
+ return true;
+}
+
+\f
+
+#if defined (HAVE_DLFCN_H) && defined (HAVE_DLADDR)
+
+// We keep a store of the filenames of DSOs that need to be
+// conservatively scanned by the garbage collector. During collection
+// the gc calls _Jv_GC_has_static_roots() to see if the data segment
+// of a DSO should be scanned.
+typedef struct filename_node
+{
+ char *name;
+ struct filename_node *link;
+} filename_node;
+
+#define FILENAME_STORE_SIZE 17
+static filename_node *filename_store[FILENAME_STORE_SIZE];
- DISABLE_SIGNALS ();
- LOCK ();
+// Find a filename in filename_store.
+static filename_node **
+find_file (const char *filename)
+{
+ int index = strlen (filename) % FILENAME_STORE_SIZE;
+ filename_node **node = &filename_store[index];
+
+ while (*node)
+ {
+ if (strcmp ((*node)->name, filename) == 0)
+ return node;
+ node = &(*node)->link;
+ }
+
+ return node;
+}
- if (initialized)
+// Print the store of filenames of DSOs that need collection.
+void
+_Jv_print_gc_store (void)
+{
+ for (int i = 0; i < FILENAME_STORE_SIZE; i++)
{
- UNLOCK ();
- ENABLE_SIGNALS ();
- return;
+ filename_node *node = filename_store[i];
+ while (node)
+ {
+ fprintf (stderr, "%s\n", node->name);
+ node = node->link;
+ }
+ }
+}
+
+// Create a new node in the store of libraries to collect.
+static filename_node *
+new_node (const char *filename)
+{
+ filename_node *node = (filename_node*)_Jv_Malloc (sizeof (filename_node));
+ node->name = (char *)_Jv_Malloc (strlen (filename) + 1);
+ node->link = NULL;
+ strcpy (node->name, filename);
+
+ return node;
+}
+
+// Nonzero if the gc should scan this lib.
+static int
+_Jv_GC_has_static_roots (const char *filename, void *, size_t)
+{
+ if (filename == NULL || strlen (filename) == 0)
+ // No filename; better safe than sorry.
+ return 1;
+
+ filename_node **node = find_file (filename);
+ if (*node)
+ return 1;
+
+ return 0;
+}
+
+#endif
+
+// Register the DSO that contains p for collection.
+void
+_Jv_RegisterLibForGc (const void *p __attribute__ ((__unused__)))
+{
+#if defined (HAVE_DLFCN_H) && defined (HAVE_DLADDR)
+ Dl_info info;
+
+ if (dladdr (const_cast<void *>(p), &info) != 0)
+ {
+ filename_node **node = find_file (info.dli_fname);
+ if (! *node)
+ *node = new_node (info.dli_fname);
}
- initialized = 1;
-
- // Set up state for marking and allocation of Java objects.
- obj_free_list = (ptr_t *) GC_generic_malloc_inner ((MAXOBJSZ + 1)
- * sizeof (ptr_t),
- PTRFREE);
- memset (obj_free_list, 0, (MAXOBJSZ + 1) * sizeof (ptr_t));
-
- proc = GC_n_mark_procs++;
- GC_mark_procs[proc] = (mark_proc) _Jv_MarkObj;
-
- obj_kind_x = GC_n_kinds++;
- GC_obj_kinds[obj_kind_x].ok_freelist = obj_free_list;
- GC_obj_kinds[obj_kind_x].ok_reclaim_list = 0;
- GC_obj_kinds[obj_kind_x].ok_descriptor = MAKE_PROC (proc, 0);
- GC_obj_kinds[obj_kind_x].ok_relocate_descr = FALSE;
- GC_obj_kinds[obj_kind_x].ok_init = TRUE;
-
- // Set up state for marking and allocation of arrays of Java
- // objects.
- array_free_list = (ptr_t *) GC_generic_malloc_inner ((MAXOBJSZ + 1)
- * sizeof (ptr_t),
- PTRFREE);
- memset (array_free_list, 0, (MAXOBJSZ + 1) * sizeof (ptr_t));
-
- proc = GC_n_mark_procs++;
- GC_mark_procs[proc] = (mark_proc) _Jv_MarkArray;
-
- array_kind_x = GC_n_kinds++;
- GC_obj_kinds[array_kind_x].ok_freelist = array_free_list;
- GC_obj_kinds[array_kind_x].ok_reclaim_list = 0;
- GC_obj_kinds[array_kind_x].ok_descriptor = MAKE_PROC (proc, 0);
- GC_obj_kinds[array_kind_x].ok_relocate_descr = FALSE;
- GC_obj_kinds[array_kind_x].ok_init = TRUE;
-
- UNLOCK ();
- ENABLE_SIGNALS ();
+#endif
+}
+
+void
+_Jv_SuspendThread (_Jv_Thread_t *thread)
+{
+#if defined(GC_PTHREADS) && !defined(GC_SOLARIS_THREADS) \
+ && !defined(GC_WIN32_THREADS) && !defined(GC_DARWIN_THREADS)
+ GC_suspend_thread (_Jv_GetPlatformThreadID (thread));
+#endif
+}
+
+void
+_Jv_ResumeThread (_Jv_Thread_t *thread)
+{
+#if defined(GC_PTHREADS) && !defined(GC_SOLARIS_THREADS) \
+ && !defined(GC_WIN32_THREADS) && !defined(GC_DARWIN_THREADS)
+ GC_resume_thread (_Jv_GetPlatformThreadID (thread));
+#endif
+}
+
+int
+_Jv_IsThreadSuspended (_Jv_Thread_t *thread)
+{
+#if defined(GC_PTHREADS) && !defined(GC_SOLARIS_THREADS) \
+ && !defined(GC_WIN32_THREADS) && !defined(GC_DARWIN_THREADS)
+ return GC_is_thread_suspended (_Jv_GetPlatformThreadID (thread));
+#else
+ return 0;
+#endif
+}
+
+void
+_Jv_GCAttachThread ()
+{
+ // The registration interface is only defined on posixy systems and
+ // only actually works if pthread_getattr_np is defined.
+ // FIXME: until gc7 it is simpler to disable this on solaris.
+#if defined(HAVE_PTHREAD_GETATTR_NP) && !defined(GC_SOLARIS_THREADS)
+ GC_register_my_thread ();
+#endif
+}
+
+void
+_Jv_GCDetachThread ()
+{
+#if defined(HAVE_PTHREAD_GETATTR_NP) && !defined(GC_SOLARIS_THREADS)
+ GC_unregister_my_thread ();
+#endif
}
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