new macro 'resetoldbit'

lgc.c

@@ -1,5 +1,5 @@
 /*
-** $Id: lgc.c,v 2.91 2010/05/07 18:19:36 roberto Exp roberto $
+** $Id: lgc.c,v 2.92 2010/05/07 18:43:24 roberto Exp roberto $
 ** Garbage Collector
 ** See Copyright Notice in lua.h
 */
@@ -164,7 +164,7 @@ void luaC_checkupvalcolor (global_State *g, UpVal *uv) {
   lua_assert(!isblack(o));  /* open upvalues are never black */
   if (isgray(o)) {
     if (keepinvariant(g)) {
-      resetbit(o->gch.marked, OLDBIT);
+      resetoldbit(o);
       gray2black(o);  /* it is being visited now */
       markvalue(g, uv->v);
     }
@@ -729,7 +729,7 @@ void luaC_separateudata (lua_State *L, int all) {
       p = &gch(curr)->next;  /* don't bother with it */
     else {
       l_setbit(gch(curr)->marked, FINALIZEDBIT); /* won't be finalized again */
-      resetbit(gch(curr)->marked, OLDBIT); /* may be old when 'all' */
+      resetoldbit(curr); /* may be old when 'all' is true */
       *p = gch(curr)->next;  /* remove 'curr' from 'udgc' list */
       gch(curr)->next = *lastnext;  /* link at the end of 'tobefnz' list */
       *lastnext = curr;
@@ -745,7 +745,7 @@ void luaC_separateudata (lua_State *L, int all) {
 */
 void luaC_checkfinalizer (lua_State *L, Udata *u) {
   global_State *g = G(L);
-  if (testbit(u->uv.marked, SEPARATED) || /* userdata is already separated... */
+  if (testbit(u->uv.marked, SEPARATED) || /* udata is already separated... */
       isfinalized(&u->uv) ||                     /* ... or is finalized... */
       gfasttm(g, u->uv.metatable, TM_GC) == NULL)  /* or has no finalizer? */
     return;  /* nothing to be done */
@@ -756,7 +756,7 @@ void luaC_checkfinalizer (lua_State *L, Udata *u) {
     u->uv.next = g->udgc;  /* link it in list 'udgc' */
     g->udgc = obj2gco(u);
     l_setbit(u->uv.marked, SEPARATED);  /* mark it as such */
-    resetbit(u->uv.marked, OLDBIT);
+    resetoldbit(obj2gco(u));
   }
 }
 

lgc.h

@@ -1,5 +1,5 @@
 /*
-** $Id: lgc.h,v 2.38 2010/05/07 18:08:05 roberto Exp roberto $
+** $Id: lgc.h,v 2.39 2010/05/07 18:43:51 roberto Exp roberto $
 ** Garbage Collector
 ** See Copyright Notice in lua.h
 */
@@ -80,6 +80,7 @@
 #define SEPARATED	4  /*  "    ": it's in 'udgc' list or in 'tobefnz' */
 #define FIXEDBIT	5  /* object is fixed (should not be collected) */
 #define OLDBIT		6  /* object is old (only in generational mode) */
+/* bit 7 is currently used by tests (luaL_checkmemory) */
 
 #define WHITEBITS	bit2mask(WHITE0BIT, WHITE1BIT)
 
@@ -90,6 +91,7 @@
 	(!testbits((x)->gch.marked, WHITEBITS | bitmask(BLACKBIT)))
 
 #define isold(x)	testbit((x)->gch.marked, OLDBIT)
+#define resetoldbit(o)	resetbit((o)->gch.marked, OLDBIT)
 
 #define otherwhite(g)	(g->currentwhite ^ WHITEBITS)
 #define isdeadm(ow,m)	(!(((m) ^ WHITEBITS) & (ow)))