diff --git a/src/gc.c b/src/gc.c
index 7b0a36e5d35433a89f100c3aafbbf1ccf18ddfe2..daad51cc71dda2ae777a615a2bb9ffdb6944d45d 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -29,7 +29,7 @@ struct callback *gc_evaluator_callback=0;
#include "block_alloc.h"
-RCSID("$Id: gc.c,v 1.85 2000/06/09 22:43:04 mast Exp $");
+RCSID("$Id: gc.c,v 1.86 2000/06/10 18:09:17 mast Exp $");
/* Run garbage collect approximately every time
* 20 percent of all arrays, objects and programs is
@@ -1055,8 +1055,9 @@ static void break_cycle (struct marker *beg, struct marker *pos)
* where the "stack top" is.) */
struct marker *p, *q;
+ int cycle = beg->cycle;
#ifdef GC_CYCLE_DEBUG
- fprintf(stderr, "%*sgc_cycle_push, break cycle: %8p, [%8p] ",
+ fprintf(stderr, "%*sbreak cycle: %8p, [%8p] ",
gc_cycle_indent, "", beg->data, gc_rec_last);
describe_marker(beg);
#endif
@@ -1065,30 +1066,30 @@ static void break_cycle (struct marker *beg, struct marker *pos)
gc_fatal(beg->data, 0, "Cycle already broken at requested position.\n");
#endif
- if (beg->cycle) {
+ if (cycle) {
#ifdef PIKE_DEBUG
- if (pos->cycle == beg->cycle || gc_rec_last->cycle == beg->cycle)
- gc_fatal(beg->data, 0, "Same cycle on both sides of broken link.\n");
+ if (pos->cycle == cycle || gc_rec_last->cycle == cycle)
+ gc_fatal(pos->data, 0, "Same cycle on both sides of broken link.\n");
#endif
for (p = &rec_list; p->link->cycle != beg->cycle; p = p->link) {}
}
else
for (p = &rec_list; p->link != beg; p = p->link) {}
- /* for (q = gc_rec_last; q->link; q = q->link) {} */
- /* q->link = p->link; */
q = p->link;
p->link = pos;
while (q != pos) {
- q->flags &= ~(GC_CYCLE_CHECKED|GC_RECURSING|GC_WEAK_REF);
+ q->flags &= ~(GC_CYCLE_CHECKED|GC_RECURSING|GC_WEAK_REF|GC_FOLLOWED_NONSTRONG);
q->cycle = 0;
#ifdef GC_CYCLE_DEBUG
- fprintf(stderr, "%*sgc_cycle_push, reset: "
+ fprintf(stderr, "%*sreset marker: "
"%8p, ", gc_cycle_indent, "", q->data);
describe_marker(q);
#endif
#ifdef PIKE_DEBUG
+ if (q->flags & (GC_GOT_DEAD_REF|GC_GOT_EXTRA_REF))
+ gc_fatal(q->data, 0, "Didn't expect an extra ref at reset.\n");
p = q->link;
q->link = (struct marker *) -1;
q = p;
@@ -1131,6 +1132,9 @@ int gc_cycle_push(void *x, struct marker *m, int weak)
gc_fatal(x, 0, "gc_cycle_check() called for thing not on gc_internal lists.\n");
on_gc_internal_lists:
}
+ if (weak < 0 && gc_rec_last->flags & GC_FOLLOWED_NONSTRONG)
+ gc_fatal(x, 0, "Followed strong link too late.\n");
+ if (weak >= 0) gc_rec_last->flags |= GC_FOLLOWED_NONSTRONG;
#endif
if (gc_rec_last->flags & GC_LIVE_RECURSE) {
@@ -1368,6 +1372,20 @@ live_recurse:
return 1;
}
+/* Add an extra ref when a dead thing is popped. It's taken away in
+ * the free pass. This is done to not refcount garb the cycles
+ * themselves recursively, which in bad cases can consume a lot of C
+ * stack. */
+#define ADD_REF_IF_DEAD(M) \
+ if (!(M->flags & GC_LIVE)) { \
+ DO_IF_DEBUG( \
+ if (M->flags & GC_GOT_DEAD_REF) \
+ gc_fatal(M->data, 0, "A thing already got an extra dead cycle ref.\n"); \
+ ); \
+ gc_add_extra_ref(M->data); \
+ M->flags |= GC_GOT_DEAD_REF; \
+ }
+
static void pop_cycle_to_kill_list()
{
struct marker *base, *p, *q;
@@ -1385,8 +1403,11 @@ static void pop_cycle_to_kill_list()
gc_fatal(q->data, 0, "Popping more than one cycle from rec_list.\n");
if (!(q->flags & GC_RECURSING))
gc_fatal(q->data, 0, "Marker being cycle popped doesn't have GC_RECURSING.\n");
+ if (q->flags & GC_GOT_DEAD_REF)
+ gc_fatal(q->data, 0, "Didn't expect a dead extra ref.\n");
#endif
q->flags &= ~GC_RECURSING;
+
if (q->flags & GC_LIVE_OBJ) {
/* This extra ref is taken away in the kill pass. */
gc_add_extra_ref(q->data);
@@ -1398,6 +1419,7 @@ static void pop_cycle_to_kill_list()
p = q;
}
else {
+ ADD_REF_IF_DEAD(q);
#ifdef GC_CYCLE_DEBUG
fprintf(stderr, "%*spop_cycle_to_kill_list, ignore: %8p, [%8p] ",
gc_cycle_indent, "", q->data, base);
@@ -1441,17 +1463,10 @@ void gc_cycle_pop(void *a)
return;
}
- if (!(m->flags & GC_LIVE)) {
- /* This extra ref is taken away in the free pass. This is done to
- * not refcount garb the cycles themselves recursively, which in bad
- * cases can consume a lot of C stack. */
- gc_add_extra_ref(m->data);
#ifdef PIKE_DEBUG
- if (m->flags & GC_GOT_DEAD_REF)
- gc_fatal(a, 0, "A thing already got an extra dead cycle ref.\n");
+ if (m->flags & GC_GOT_DEAD_REF)
+ gc_fatal(a, 0, "Didn't expect a dead extra ref.\n");
#endif
- m->flags |= GC_GOT_DEAD_REF;
- }
if (m->cycle) {
/* Part of a cycle. Leave for now so we pop the whole cycle at once. */
@@ -1472,6 +1487,7 @@ void gc_cycle_pop(void *a)
else {
struct marker *p;
+ ADD_REF_IF_DEAD(m);
m->flags &= ~(GC_RECURSING|GC_WEAK_REF);
if (gc_rec_last->flags & GC_RECURSING) p = gc_rec_last;
else p = &rec_list;
@@ -1519,17 +1535,10 @@ void gc_cycle_pop_object(struct object *o)
return;
}
- if (!(m->flags & GC_LIVE)) {
- /* This extra ref is taken away in the free pass. This is done to
- * not refcount garb the cycles themselves recursively, which in bad
- * cases can consume a lot of C stack. */
- gc_add_extra_ref(o);
#ifdef PIKE_DEBUG
- if (m->flags & GC_GOT_DEAD_REF)
- gc_fatal(o, 0, "An object already got an extra dead cycle ref.\n");
+ if (m->flags & GC_GOT_DEAD_REF)
+ gc_fatal(o, 0, "Didn't expect a dead extra ref.\n");
#endif
- m->flags |= GC_GOT_DEAD_REF;
- }
if (m->cycle) {
/* Part of a cycle. Leave for now so we pop the whole cycle at once. */
@@ -1569,8 +1578,11 @@ void gc_cycle_pop_object(struct object *o)
fprintf(stderr, "%*sgc_cycle_pop_object, for kill: %8p, [%8p] ",
gc_cycle_indent, "", o, gc_rec_last);
describe_marker(m);
+#endif
}
else {
+ ADD_REF_IF_DEAD(m);
+#ifdef GC_CYCLE_DEBUG
fprintf(stderr,"%*sgc_cycle_pop_object: %8p, [%8p] ",
gc_cycle_indent, "", o, gc_rec_last);
describe_marker(m);
diff --git a/src/gc.h b/src/gc.h
index f84336786e5dda46266b3b4c6339cce5474c35ec..9ad2b4ca4c69450cf2b5d8c0d026400beaaad183 100644
--- a/src/gc.h
+++ b/src/gc.h
@@ -1,5 +1,5 @@
/*
- * $Id: gc.h,v 1.42 2000/06/09 22:43:04 mast Exp $
+ * $Id: gc.h,v 1.43 2000/06/10 18:09:18 mast Exp $
*/
#ifndef GC_H
#define GC_H
@@ -91,6 +91,7 @@ struct marker
#define GC_DO_FREE 0x1000
#define GC_IS_ONLY_WEAK 0x2000
#define GC_GOT_EXTRA_REF 0x4000
+#define GC_FOLLOWED_NONSTRONG 0x8000
#include "block_alloc_h.h"
PTR_HASH_ALLOC(marker,MARKER_CHUNK_SIZE)
@@ -212,7 +213,8 @@ extern int gc_in_cycle_check;
/* Use WEAK < 0 for strong links. The gc makes these assumptions about
* those:
- * 1. All strong links are recursed before any other links.
+ * 1. All strong links are recursed before any other links, i.e.
+ * strong links should be pushed last into the lifo queue.
* 2. There can never be a cycle consisting of only strong links.
*/
diff --git a/src/object.c b/src/object.c
index 6d485a43078fe832180644fc10fcb09a99414494..1caefcba204c090ffd6a4805a658c2c6b25e5f61 100644
--- a/src/object.c
+++ b/src/object.c
@@ -5,7 +5,7 @@
\*/
/**/
#include "global.h"
-RCSID("$Id: object.c,v 1.123 2000/06/10 11:52:43 mast Exp $");
+RCSID("$Id: object.c,v 1.124 2000/06/10 18:09:18 mast Exp $");
#include "object.h"
#include "dynamic_buffer.h"
#include "interpret.h"
@@ -1244,9 +1244,6 @@ static void low_gc_cycle_check_object(struct object *o)
if (!o2) fatal("Object not on gc_internal_object list.\n");
#endif
- if(o->parent)
- gc_cycle_check_object_strong(o->parent);
-
LOW_PUSH_FRAME(o);
for(e=p->num_inherits-1; e>=0; e--)
@@ -1284,6 +1281,10 @@ static void low_gc_cycle_check_object(struct object *o)
}
LOW_POP_FRAME();
+
+ /* This must be last. */
+ if(o->parent)
+ gc_cycle_check_object_strong(o->parent);
}
}