Reorganize flags values for classes; fix #3975

Renamed flag macro names as well:
`MRB_FLAG_IS_FROZEN` -> `MRB_FL_OBJ_FROZEN`
`MRB_FLAG_IS_PREPENDED` -> `MRB_FL_CLASS_IS_PREPENDED`
`MRB_FLAG_IS_ORIGIN` -> `MRB_FL_CLASS_IS_ORIGIN`
`MRB_FLAG_IS_INHERITED` -> `MRB_FL_CLASS_IS_INHERITED`

5 files changed, 36 insertions, 31 deletions

diff --git a/include/mruby/class.h b/include/mruby/class.h
index ea35d8e17..6e6f11eb8 100644
--- a/include/mruby/class.h
+++ b/include/mruby/class.h
@@ -53,19 +53,25 @@ mrb_class(mrb_state *mrb, mrb_value v)
   }
 }
 
-/* TODO: figure out where to put user flags */
-/* flags bits >= 18 is reserved */
-#define MRB_FLAG_IS_PREPENDED (1 << 19)
-#define MRB_FLAG_IS_ORIGIN (1 << 20)
+/* flags:
+   20: frozen
+   19: is_prepended
+   18: is_origin
+   17: is_inherited (used by method cache)
+   16: unused
+   0-15: instance type
+*/
+#define MRB_FL_CLASS_IS_PREPENDED (1 << 19)
+#define MRB_FL_CLASS_IS_ORIGIN (1 << 18)
 #define MRB_CLASS_ORIGIN(c) do {\
-  if (c->flags & MRB_FLAG_IS_PREPENDED) {\
+  if (c->flags & MRB_FL_CLASS_IS_PREPENDED) {\
     c = c->super;\
-    while (!(c->flags & MRB_FLAG_IS_ORIGIN)) {\
+    while (!(c->flags & MRB_FL_CLASS_IS_ORIGIN)) {\
       c = c->super;\
     }\
   }\
 } while (0)
-#define MRB_FLAG_IS_INHERITED (1 << 21)
+#define MRB_FL_CLASS_IS_INHERITED (1 << 17)
 #define MRB_INSTANCE_TT_MASK (0xFF)
 #define MRB_SET_INSTANCE_TT(c, tt) c->flags = ((c->flags & ~MRB_INSTANCE_TT_MASK) | (char)tt)
 #define MRB_INSTANCE_TT(c) (enum mrb_vtype)(c->flags & MRB_INSTANCE_TT_MASK)
diff --git a/include/mruby/object.h b/include/mruby/object.h
index 4f2134ae2..25584a1d4 100644
--- a/include/mruby/object.h
+++ b/include/mruby/object.h
@@ -22,11 +22,10 @@ struct RBasic {
 };
 #define mrb_basic_ptr(v) ((struct RBasic*)(mrb_ptr(v)))
 
-/* flags bits >= 18 is reserved */
-#define MRB_FLAG_IS_FROZEN (1 << 18)
-#define MRB_FROZEN_P(o) ((o)->flags & MRB_FLAG_IS_FROZEN)
-#define MRB_SET_FROZEN_FLAG(o) ((o)->flags |= MRB_FLAG_IS_FROZEN)
-#define MRB_UNSET_FROZEN_FLAG(o) ((o)->flags &= ~MRB_FLAG_IS_FROZEN)
+#define MRB_FL_OBJ_IS_FROZEN (1 << 20)
+#define MRB_FROZEN_P(o) ((o)->flags & MRB_FL_OBJ_IS_FROZEN)
+#define MRB_SET_FROZEN_FLAG(o) ((o)->flags |= MRB_FL_OBJ_IS_FROZEN)
+#define MRB_UNSET_FROZEN_FLAG(o) ((o)->flags &= ~MRB_FL_OBJ_IS_FROZEN)
 
 struct RObject {
   MRB_OBJECT_HEADER;
diff --git a/src/class.c b/src/class.c
index a9439d7d7..97b5df926 100644
--- a/src/class.c
+++ b/src/class.c
@@ -93,7 +93,7 @@ prepare_singleton_class(mrb_state *mrb, struct RBasic *o)
 
   if (o->c->tt == MRB_TT_SCLASS) return;
   sc = (struct RClass*)mrb_obj_alloc(mrb, MRB_TT_SCLASS, mrb->class_class);
-  sc->flags |= MRB_FLAG_IS_INHERITED;
+  sc->flags |= MRB_FL_CLASS_IS_INHERITED;
   sc->mt = kh_init(mt, mrb);
   sc->iv = 0;
   if (o->tt == MRB_TT_CLASS) {
@@ -275,7 +275,7 @@ mrb_class_inherited(mrb_state *mrb, struct RClass *super, struct RClass *klass)
 
   if (!super)
     super = mrb->object_class;
-  super->flags |= MRB_FLAG_IS_INHERITED;
+  super->flags |= MRB_FL_CLASS_IS_INHERITED;
   s = mrb_obj_value(super);
   mc_clear_by_class(mrb, klass);
   mid = mrb_intern_lit(mrb, "inherited");
@@ -1061,7 +1061,7 @@ include_module_at(mrb_state *mrb, struct RClass *c, struct RClass *ins_pos, stru
   while (m) {
     int superclass_seen = 0;
 
-    if (m->flags & MRB_FLAG_IS_PREPENDED)
+    if (m->flags & MRB_FL_CLASS_IS_PREPENDED)
       goto skip;
 
     if (klass_mt && klass_mt == m->mt)
@@ -1084,7 +1084,7 @@ include_module_at(mrb_state *mrb, struct RClass *c, struct RClass *ins_pos, stru
     }
 
     ic = include_class_new(mrb, m, ins_pos->super);
-    m->flags |= MRB_FLAG_IS_INHERITED;
+    m->flags |= MRB_FL_CLASS_IS_INHERITED;
     ins_pos->super = ic;
     mrb_field_write_barrier(mrb, (struct RBasic*)ins_pos, (struct RBasic*)ic);
     mc_clear_by_class(mrb, ins_pos);
@@ -1111,15 +1111,15 @@ mrb_prepend_module(mrb_state *mrb, struct RClass *c, struct RClass *m)
   struct RClass *origin;
   int changed = 0;
 
-  if (!(c->flags & MRB_FLAG_IS_PREPENDED)) {
+  if (!(c->flags & MRB_FL_CLASS_IS_PREPENDED)) {
     origin = (struct RClass*)mrb_obj_alloc(mrb, MRB_TT_ICLASS, c);
-    origin->flags |= MRB_FLAG_IS_ORIGIN | MRB_FLAG_IS_INHERITED;
+    origin->flags |= MRB_FL_CLASS_IS_ORIGIN | MRB_FL_CLASS_IS_INHERITED;
     origin->super = c->super;
     c->super = origin;
     origin->mt = c->mt;
     c->mt = kh_init(mt, mrb);
     mrb_field_write_barrier(mrb, (struct RBasic*)c, (struct RBasic*)origin);
-    c->flags |= MRB_FLAG_IS_PREPENDED;
+    c->flags |= MRB_FL_CLASS_IS_PREPENDED;
   }
   changed = include_module_at(mrb, c, c, m, 0);
   if (changed < 0) {
@@ -1196,7 +1196,7 @@ mrb_mod_ancestors(mrb_state *mrb, mrb_value self)
     if (c->tt == MRB_TT_ICLASS) {
       mrb_ary_push(mrb, result, mrb_obj_value(c->c));
     }
-    else if (!(c->flags & MRB_FLAG_IS_PREPENDED)) {
+    else if (!(c->flags & MRB_FL_CLASS_IS_PREPENDED)) {
       mrb_ary_push(mrb, result, mrb_obj_value(c));
     }
     c = c->super;
@@ -1365,9 +1365,9 @@ mc_clear_by_class(mrb_state *mrb, struct RClass *c)
   struct mrb_cache_entry *mc = mrb->cache;
   int i;
 
-  if (c->flags & MRB_FLAG_IS_INHERITED) {
+  if (c->flags & MRB_FL_CLASS_IS_INHERITED) {
     mc_clear_all(mrb);
-    c->flags &= ~MRB_FLAG_IS_INHERITED;
+    c->flags &= ~MRB_FL_CLASS_IS_INHERITED;
     return;
   }
   for (i=0; i<MRB_METHOD_CACHE_SIZE; i++) {
@@ -1381,9 +1381,9 @@ mc_clear_by_id(mrb_state *mrb, struct RClass *c, mrb_sym mid)
   struct mrb_cache_entry *mc = mrb->cache;
   int i;
 
-  if (c->flags & MRB_FLAG_IS_INHERITED) {
+  if (c->flags & MRB_FL_CLASS_IS_INHERITED) {
     mc_clear_all(mrb);
-    c->flags &= ~MRB_FLAG_IS_INHERITED;
+    c->flags &= ~MRB_FL_CLASS_IS_INHERITED;
     return;
   }
   for (i=0; i<MRB_METHOD_CACHE_SIZE; i++) {
diff --git a/src/gc.c b/src/gc.c
index 69121d630..c52641959 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -622,7 +622,7 @@ gc_mark_children(mrb_state *mrb, mrb_gc *gc, struct RBasic *obj)
   case MRB_TT_ICLASS:
     {
       struct RClass *c = (struct RClass*)obj;
-      if (MRB_FLAG_TEST(c, MRB_FLAG_IS_ORIGIN))
+      if (MRB_FLAG_TEST(c, MRB_FL_CLASS_IS_ORIGIN))
         mrb_gc_mark_mt(mrb, c);
       mrb_gc_mark(mrb, (struct RBasic*)((struct RClass*)obj)->super);
     }
@@ -761,7 +761,7 @@ obj_free(mrb_state *mrb, struct RBasic *obj, int end)
     mrb_gc_free_iv(mrb, (struct RObject*)obj);
     break;
   case MRB_TT_ICLASS:
-    if (MRB_FLAG_TEST(obj, MRB_FLAG_IS_ORIGIN))
+    if (MRB_FLAG_TEST(obj, MRB_FL_CLASS_IS_ORIGIN))
       mrb_gc_free_mt(mrb, (struct RClass*)obj);
     break;
   case MRB_TT_ENV:
diff --git a/src/kernel.c b/src/kernel.c
index bbe6e8bb7..7459c83af 100644
--- a/src/kernel.c
+++ b/src/kernel.c
@@ -252,18 +252,18 @@ copy_class(mrb_state *mrb, mrb_value dst, mrb_value src)
   struct RClass *sc = mrb_class_ptr(src);
   /* if the origin is not the same as the class, then the origin and
      the current class need to be copied */
-  if (sc->flags & MRB_FLAG_IS_PREPENDED) {
+  if (sc->flags & MRB_FL_CLASS_IS_PREPENDED) {
     struct RClass *c0 = sc->super;
     struct RClass *c1 = dc;
 
     /* copy prepended iclasses */
-    while (!(c0->flags & MRB_FLAG_IS_ORIGIN)) {
+    while (!(c0->flags & MRB_FL_CLASS_IS_ORIGIN)) {
       c1->super = mrb_class_ptr(mrb_obj_dup(mrb, mrb_obj_value(c0)));
       c1 = c1->super;
       c0 = c0->super;
     }
     c1->super = mrb_class_ptr(mrb_obj_dup(mrb, mrb_obj_value(c0)));
-    c1->super->flags |= MRB_FLAG_IS_ORIGIN;
+    c1->super->flags |= MRB_FL_CLASS_IS_ORIGIN;
   }
   if (sc->mt) {
     dc->mt = kh_copy(mt, mrb, sc->mt);
@@ -348,7 +348,7 @@ mrb_obj_clone(mrb_state *mrb, mrb_value self)
   mrb_field_write_barrier(mrb, (struct RBasic*)p, (struct RBasic*)p->c);
   clone = mrb_obj_value(p);
   init_copy(mrb, clone, self);
-  p->flags |= mrb_obj_ptr(self)->flags & MRB_FLAG_IS_FROZEN;
+  p->flags |= mrb_obj_ptr(self)->flags & MRB_FL_OBJ_IS_FROZEN;
 
   return clone;
 }
@@ -706,7 +706,7 @@ mrb_class_instance_method_list(mrb_state *mrb, mrb_bool recur, struct RClass* kl
   struct RClass* oldklass;
   khash_t(st)* set = kh_init(st, mrb);
 
-  if (!recur && (klass->flags & MRB_FLAG_IS_PREPENDED)) {
+  if (!recur && (klass->flags & MRB_FL_CLASS_IS_PREPENDED)) {
     MRB_CLASS_ORIGIN(klass);
     prepended = TRUE;
   }