Restructure `irep->outer` chain; fix
Instead of `irep -> proc` chain, we use `irep -> irep` chain to
avoid GC bugs like We added `target_class` reference to
`mrb_irep` struct. That means one more word consumption per `irep`.
MODIFY
include/mruby/irep.h
include/mruby/irep.h
@@ -46,7 +46,8 @@ typedef struct mrb_irep {
int ilen, plen, slen, rlen, refcnt;
- struct RProc *outer; /* Refers outer scope */
+ struct mrb_irep *outer; /* Refers outer scope */
+ struct RClass *target_class;
} mrb_irep;
#define MRB_ISEQ_NO_FREE 1

MODIFY
include/mruby/proc.h
include/mruby/proc.h
@@ -57,8 +57,6 @@ struct RProc {
#define MRB_PROC_STRICT_P(p) (((p)->flags & MRB_PROC_STRICT) != 0)
#define MRB_PROC_ORPHAN 512
#define MRB_PROC_ORPHAN_P(p) (((p)->flags & MRB_PROC_ORPHAN) != 0)
-#define MRB_PROC_CLASS 1024
-#define MRB_PROC_CLASS_P(p) (((p)->flags & MRB_PROC_CLASS) != 0)
#define mrb_proc_ptr(v) ((struct RProc*)(mrb_ptr(v)))

MODIFY
src/gc.c
src/gc.c
@@ -648,7 +648,7 @@ gc_mark_children(mrb_state *mrb, mrb_gc *gc, struct RBasic *obj)
mrb_gc_mark(mrb, (struct RBasic*)p->env);
mrb_gc_mark(mrb, (struct RBasic*)p->target_class);
if (!MRB_PROC_CFUNC_P(p) && p->body.irep) {
- mrb_gc_mark(mrb, (struct RBasic*)p->body.irep->outer);
+ mrb_gc_mark(mrb, (struct RBasic*)p->body.irep->target_class);
}
}
break;

MODIFY
src/kernel.c
src/kernel.c
@@ -1151,8 +1151,8 @@ static mrb_value
mrb_local_variables(mrb_state *mrb, mrb_value self)
{
struct RProc *proc;
+ mrb_irep *irep;
mrb_value vars;
- struct mrb_irep *irep;
size_t i;
proc = mrb->c->ci[-1].proc;
@@ -1161,18 +1161,16 @@ mrb_local_variables(mrb_state *mrb, mrb_value self)
return mrb_ary_new(mrb);
}
vars = mrb_hash_new(mrb);
- while (proc) {
- if (MRB_PROC_CFUNC_P(proc)) break;
irep = proc->body.irep;
+ while (irep) {
if (!irep->lv) break;
for (i = 0; i + 1 < irep->nlocals; ++i) {
if (irep->lv[i].name) {
mrb_hash_set(mrb, vars, mrb_symbol_value(irep->lv[i].name), mrb_true_value());
}
}
- if (MRB_PROC_CLASS_P(proc)) break;
if (!proc->env) break;
- proc = proc->body.irep->outer;
+ irep = irep->outer;
}
return mrb_hash_keys(mrb, vars);

MODIFY
src/state.c
src/state.c
@@ -157,6 +157,8 @@ mrb_irep_free(mrb_state *mrb, mrb_irep *irep)
for (i=0; i<irep->rlen; i++) {
mrb_irep_decref(mrb, irep->reps[i]);
}
+ if (irep->outer)
+ mrb_irep_decref(mrb, irep->outer);
mrb_free(mrb, irep->reps);
mrb_free(mrb, irep->lv);
if (irep->own_filename) {

MODIFY
src/variable.c
src/variable.c
@@ -702,7 +702,7 @@ mrb_vm_const_get(mrb_state *mrb, mrb_sym sym)
struct RClass *c = mrb->c->ci->proc->target_class;
struct RClass *c2;
mrb_value v;
- struct RProc *proc;
+ mrb_irep *irep;
if (!c) c = mrb->c->ci->target_class;
mrb_assert(c != NULL);
@@ -719,16 +719,15 @@ mrb_vm_const_get(mrb_state *mrb, mrb_sym sym)
}
if (c2->tt == MRB_TT_CLASS || c2->tt == MRB_TT_MODULE) c = c2;
mrb_assert(!MRB_PROC_CFUNC_P(mrb->c->ci->proc));
- proc = mrb->c->ci->proc->body.irep->outer;
- while (proc && proc->tt == MRB_TT_PROC) {
- mrb_assert(!MRB_PROC_CFUNC_P(proc));
- if (MRB_PROC_CLASS_P(proc) && proc->target_class) {
- c2 = proc->target_class;
+ irep = mrb->c->ci->proc->body.irep;
+ while (irep) {
+ if (irep->target_class) {
+ c2 = irep->target_class;
if (c2->iv && iv_get(mrb, c2->iv, sym, &v)) {
return v;
}
}
- proc = proc->body.irep->outer;
+ irep = irep->outer;
}
return const_get(mrb, c, sym);
}

MODIFY
src/vm.c
src/vm.c
@@ -770,17 +770,23 @@ mrb_value
mrb_mod_s_nesting(mrb_state *mrb, mrb_value mod)
{
struct RProc *proc;
+ mrb_irep *irep;
mrb_value ary;
+ struct RClass *c;
mrb_get_args(mrb, "");
ary = mrb_ary_new(mrb);
proc = mrb->c->ci[-1].proc; /* callee proc */
- while (proc) {
+ c = proc->target_class;
+ mrb_ary_push(mrb, ary, mrb_obj_value(c));
mrb_assert(!MRB_PROC_CFUNC_P(proc));
- if (MRB_PROC_CLASS_P(proc) && proc->target_class) {
- mrb_ary_push(mrb, ary, mrb_obj_value(proc->target_class));
+ irep = proc->body.irep;
+ while (irep) {
+ if (irep->target_class && irep->target_class != c) {
+ c = irep->target_class;
+ mrb_ary_push(mrb, ary, mrb_obj_value(c));
}
- proc = proc->body.irep->outer;
+ irep = irep->outer;
}
return ary;
}
@@ -846,6 +852,18 @@ argnum_error(mrb_state *mrb, mrb_int num)
mrb_exc_set(mrb, exc);
}
+void
+irep_uplink(mrb_state *mrb, mrb_irep *outer, mrb_irep *irep)
+{
+ if (irep->outer != outer) {
+ if (irep->outer) {
+ mrb_irep_decref(mrb, irep->outer);
+ }
+ irep->outer = outer;
+ mrb_irep_incref(mrb, outer);
+ }
+}
+
#define ERR_PC_SET(mrb, pc) mrb->c->ci->err = pc;
#define ERR_PC_CLR(mrb) mrb->c->ci->err = 0;
#ifdef MRB_ENABLE_DEBUG_HOOK
@@ -2647,7 +2665,7 @@ RETRY_TRY_BLOCK:
int c = GETARG_c(i);
mrb_irep *nirep = irep->reps[b];
- nirep->outer = mrb->c->ci->proc;
+ irep_uplink(mrb, irep, nirep);
if (c & OP_L_CAPTURE) {
p = mrb_closure_new(mrb, nirep);
}
@@ -2716,11 +2734,11 @@ RETRY_TRY_BLOCK:
struct RProc *p;
mrb_irep *nirep = irep->reps[bx];
- nirep->outer = mrb->c->ci->proc;
+ irep_uplink(mrb, irep, nirep);
+ nirep->target_class = mrb_class_ptr(recv);
/* prepare closure */
p = mrb_closure_new(mrb, nirep);
p->c = NULL;
- p->flags |= MRB_PROC_CLASS;
/* prepare stack */
ci = cipush(mrb);

Restructure `irep->outer` chain; fix #3804

Instead of `irep -> proc` chain, we use `irep -> irep` chain to
avoid GC bugs like #3804. We added `target_class` reference to
`mrb_irep` struct. That means one more word consumption per `irep`.