altos/lisp: Make sure memmove only happens once per object. Other GC fixes

[fw/altos] / src / lisp / ao_lisp_cons.c

diff --git a/src/lisp/ao_lisp_cons.c b/src/lisp/ao_lisp_cons.c
index b75ffaa0d611ffa5427e7b191d4d68d996e74534..c7d8382f79d19c1d563516997fee1dce9b3dad18 100644 (file)
--- a/src/lisp/ao_lisp_cons.c
+++ b/src/lisp/ao_lisp_cons.c
@@ -49,6 +49,8 @@ static void cons_move(void *addr)
 
                (void) ao_lisp_poly_move(&cons->car, 1);
                cdr = ao_lisp_poly_cons(cons->cdr);
+               if (!cdr)
+                       break;
                ret = ao_lisp_move_memory((void **) &cdr, sizeof (struct ao_lisp_cons));
                if (cdr != ao_lisp_poly_cons(cons->cdr))
                        cons->cdr = ao_lisp_cons_poly(cdr);
@@ -64,20 +66,29 @@ const struct ao_lisp_type ao_lisp_cons_type = {
        .move = cons_move,
 };
 
+static ao_poly cons_car;
+static struct ao_lisp_cons *cons_cdr;
+static int been_here;
+
 struct ao_lisp_cons *
 ao_lisp_cons_cons(ao_poly car, struct ao_lisp_cons *cdr)
 {
        struct ao_lisp_cons     *cons;
 
-       ao_lisp_root_add(&ao_lisp_cons_type, &cdr);
-       ao_lisp_root_poly_add(&car);
+       if (!been_here) {
+               ao_lisp_root_add(&ao_lisp_cons_type, &cons_cdr);
+               ao_lisp_root_poly_add(&cons_car);
+               been_here = 1;
+       }
+       cons_car = car;
+       cons_cdr = cdr;
        cons = ao_lisp_alloc(sizeof (struct ao_lisp_cons));
-       ao_lisp_root_clear(&car);
-       ao_lisp_root_clear(&cdr);
        if (!cons)
                return NULL;
-       cons->car = car;
-       cons->cdr = ao_lisp_cons_poly(cdr);
+       cons->car = cons_car;
+       cons->cdr = ao_lisp_cons_poly(cons_cdr);
+       cons_car = AO_LISP_NIL;
+       cons_cdr = NULL;
        return cons;
 }