/* -----------------------------------------------------------------------------
- * $Id: GC.c,v 1.133 2002/04/13 05:16:25 sof Exp $
+ * $Id: GC.c,v 1.138 2002/08/16 13:29:06 simonmar Exp $
*
* (c) The GHC Team 1998-1999
*
#include "RetainerProfile.h"
#include "LdvProfile.h"
+#include <string.h>
+
/* STATIC OBJECT LIST.
*
* During GC:
* We build up a static object list while collecting generations 0..N,
* which is then appended to the static object list of generation N+1.
*/
-StgClosure* static_objects; // live static objects
-StgClosure* scavenged_static_objects; // static objects scavenged so far
+static StgClosure* static_objects; // live static objects
+StgClosure* scavenged_static_objects; // static objects scavenged so far
/* N is the oldest generation being collected, where the generations
* are numbered starting at 0. A major GC (indicated by the major_gc
/* Old to-space (used for two-space collector only)
*/
-bdescr *old_to_blocks;
+static bdescr *old_to_blocks;
/* Data used for allocation area sizing.
*/
-lnat new_blocks; // blocks allocated during this GC
-lnat g0s0_pcnt_kept = 30; // percentage of g0s0 live at last minor GC
+static lnat new_blocks; // blocks allocated during this GC
+static lnat g0s0_pcnt_kept = 30; // percentage of g0s0 live at last minor GC
/* Used to avoid long recursion due to selector thunks
*/
-lnat thunk_selector_depth = 0;
+static lnat thunk_selector_depth = 0;
#define MAX_THUNK_SELECTOR_DEPTH 256
/* -----------------------------------------------------------------------------
// start any pending finalizers
scheduleFinalizers(old_weak_ptr_list);
- ACQUIRE_LOCK(&sched_mutex);
-
// send exceptions to any threads which were about to die
resurrectThreads(resurrected_threads);
+ ACQUIRE_LOCK(&sched_mutex);
+
// Update the stable pointer hash table.
updateStablePtrTable(major_gc);
continue;
}
- ASSERT(get_itbl(w)->type == WEAK);
-
- /* Now, check whether the key is reachable.
- */
- new = isAlive(w->key);
- if (new != NULL) {
- w->key = new;
- // evacuate the value and finalizer
- w->value = evacuate(w->value);
- w->finalizer = evacuate(w->finalizer);
- // remove this weak ptr from the old_weak_ptr list
- *last_w = w->link;
- // and put it on the new weak ptr list
- next_w = w->link;
- w->link = weak_ptr_list;
- weak_ptr_list = w;
- flag = rtsTrue;
- IF_DEBUG(weak, belch("Weak pointer still alive at %p -> %p",
- w, w->key));
- continue;
- }
- else {
- last_w = &(w->link);
- next_w = w->link;
+ switch (get_itbl(w)->type) {
+
+ case EVACUATED:
+ next_w = (StgWeak *)((StgEvacuated *)w)->evacuee;
+ *last_w = next_w;
continue;
+
+ case WEAK:
+ /* Now, check whether the key is reachable.
+ */
+ new = isAlive(w->key);
+ if (new != NULL) {
+ w->key = new;
+ // evacuate the value and finalizer
+ w->value = evacuate(w->value);
+ w->finalizer = evacuate(w->finalizer);
+ // remove this weak ptr from the old_weak_ptr list
+ *last_w = w->link;
+ // and put it on the new weak ptr list
+ next_w = w->link;
+ w->link = weak_ptr_list;
+ weak_ptr_list = w;
+ flag = rtsTrue;
+ IF_DEBUG(weak, belch("Weak pointer still alive at %p -> %p",
+ w, w->key));
+ continue;
+ }
+ else {
+ last_w = &(w->link);
+ next_w = w->link;
+ continue;
+ }
+
+ default:
+ barf("traverse_weak_ptr_list: not WEAK");
}
}
last_w = list;
for (w = *list; w; w = w->link) {
+ // w might be WEAK, EVACUATED, or DEAD_WEAK (actually CON_STATIC) here
+ ASSERT(w->header.info == &stg_DEAD_WEAK_info
+ || get_itbl(w)->type == WEAK || get_itbl(w)->type == EVACUATED);
(StgClosure *)w = evacuate((StgClosure *)w);
*last_w = w;
last_w = &(w->link);
loop:
bd = Bdescr((P_)p);
+
// ignore closures in generations that we're not collecting.
if (LOOKS_LIKE_STATIC(p) || bd->gen_no > N) {
return p;
Evacuate a large object
This just consists of removing the object from the (doubly-linked)
- large_alloc_list, and linking it on to the (singly-linked)
- new_large_objects list, from where it will be scavenged later.
+ step->large_objects list, and linking it on to the (singly-linked)
+ step->new_large_objects list, from where it will be scavenged later.
Convention: bd->flags has BF_EVACUATED set for a large object
that has been evacuated, or unset otherwise.
if (HEAP_ALLOCED(q)) {
bd = Bdescr((P_)q);
- // not a group head: find the group head
- if (bd->blocks == 0) { bd = bd->link; }
-
if (bd->gen_no > N) {
/* Can't evacuate this object, because it's in a generation
* older than the ones we're collecting. Let's hope that it's