Allow classes and modules to become too complex

This makes the behavior of classes and modules when there are too many instance variables match the behavior of objects with too many instance variables.

1 files changed, 79 insertions, 23 deletions

diff --git a/variable.c b/variable.c
index c0b4625e2e..64279d881b 100644
--- a/variable.c
+++ b/variable.c
@@ -1136,6 +1136,16 @@ rb_ivar_lookup(VALUE obj, ID id, VALUE undef)
                 shape_id = RCLASS_SHAPE_ID(obj);
 #endif
 
+                if (rb_shape_obj_too_complex(obj)) {
+                    struct rb_id_table * iv_table = RCLASS_TABLE_IVPTR(obj);
+                    if (rb_id_table_lookup(iv_table, id, &val)) {
+                        return val;
+                    }
+                    else {
+                        return undef;
+                    }
+                }
+
                 attr_index_t index = 0;
                 shape = rb_shape_get_shape_by_id(shape_id);
                 found = rb_shape_get_iv_index(shape, id, &index);
@@ -1268,6 +1278,8 @@ generic_ivar_set(VALUE obj, ID id, VALUE val)
     attr_index_t index;
     // The returned shape will have `id` in its iv_table
     rb_shape_t *shape = rb_shape_get_shape(obj);
+
+    RUBY_ASSERT(!rb_shape_obj_too_complex(obj));
     bool found = rb_shape_get_iv_index(shape, id, &index);
     if (!found) {
         index = shape->next_iv_index;
@@ -1655,6 +1667,7 @@ iterate_over_shapes_with_callback(rb_shape_t *shape, rb_ivar_foreach_callback_fu
             break;
           case T_CLASS:
           case T_MODULE:
+            RUBY_ASSERT(!rb_shape_obj_too_complex(itr_data->obj));
             iv_list = RCLASS_IVPTR(itr_data->obj);
             break;
           default:
@@ -1724,7 +1737,13 @@ class_ivar_each(VALUE obj, rb_ivar_foreach_callback_func *func, st_data_t arg)
     struct iv_itr_data itr_data;
     itr_data.obj = obj;
     itr_data.arg = arg;
-    iterate_over_shapes_with_callback(shape, func, &itr_data);
+    itr_data.func = func;
+    if (rb_shape_obj_too_complex(obj)) {
+        rb_id_table_foreach(RCLASS_TABLE_IVPTR(obj), each_hash_iv, &itr_data);
+    }
+    else {
+        iterate_over_shapes_with_callback(shape, func, &itr_data);
+    }
 }
 
 void
@@ -1984,7 +2003,14 @@ rb_obj_remove_instance_variable(VALUE obj, VALUE name)
       case T_CLASS:
       case T_MODULE:
         IVAR_ACCESSOR_SHOULD_BE_MAIN_RACTOR(id);
-        rb_shape_transition_shape_remove_ivar(obj, id, shape, &val);
+        if (rb_shape_obj_too_complex(obj)) {
+            if (rb_id_table_lookup(RCLASS_TABLE_IVPTR(obj), id, &val)) {
+                rb_id_table_delete(RCLASS_TABLE_IVPTR(obj), id);
+            }
+        } else {
+            rb_shape_transition_shape_remove_ivar(obj, id, shape, &val);
+        }
+
         break;
       case T_OBJECT: {
         if (rb_shape_obj_too_complex(obj)) {
@@ -3961,35 +3987,65 @@ rb_class_ivar_set(VALUE obj, ID key, VALUE value)
 
     RB_VM_LOCK_ENTER();
     {
-        rb_shape_t * shape = rb_shape_get_shape(obj);
-        attr_index_t idx;
-        found = rb_shape_get_iv_index(shape, key, &idx);
-
-        if (found) {
-            // Changing an existing instance variable
-            RUBY_ASSERT(RCLASS_IVPTR(obj));
-
-            RCLASS_IVPTR(obj)[idx] = value;
+        if (rb_shape_obj_too_complex(obj)) {
+            struct rb_id_table * iv_table = RCLASS_TABLE_IVPTR(obj);
+            rb_id_table_insert(iv_table, key, value);
             RB_OBJ_WRITTEN(obj, Qundef, value);
+            found = 0;
         }
         else {
-            // Creating and setting a new instance variable
+            rb_shape_t * shape = rb_shape_get_shape(obj);
+            attr_index_t idx;
+            found = rb_shape_get_iv_index(shape, key, &idx);
 
-            // Move to a shape which fits the new ivar
-            idx = shape->next_iv_index;
-            shape = rb_shape_get_next(shape, obj, key);
+            if (found) {
+                // Changing an existing instance variable
+                RUBY_ASSERT(RCLASS_IVPTR(obj));
 
-            // We always allocate a power of two sized IV array. This way we
-            // only need to realloc when we expand into a new power of two size
-            if ((idx & (idx - 1)) == 0) {
-                size_t newsize = idx ? idx * 2 : 1;
-                REALLOC_N(RCLASS_IVPTR(obj), VALUE, newsize);
+                RCLASS_IVPTR(obj)[idx] = value;
+                RB_OBJ_WRITTEN(obj, Qundef, value);
             }
+            else {
+                // Creating and setting a new instance variable
+
+                // Move to a shape which fits the new ivar
+                idx = shape->next_iv_index;
+                shape = rb_shape_get_next(shape, obj, key);
+
+                // stop using shapes if we are now too complex
+                if (shape->type == SHAPE_OBJ_TOO_COMPLEX) {
+                    struct rb_id_table * table = rb_id_table_create(shape->next_iv_index);
+
+                    // Evacuate all previous values from shape into id_table
+                    rb_ivar_foreach(obj, rb_obj_evacuate_ivs_to_hash_table, (st_data_t)table);
+
+                    // insert the new value
+                    rb_id_table_insert(table, key, value);
+                    RB_OBJ_WRITTEN(obj, Qundef, value);
 
-            RUBY_ASSERT(RCLASS_IVPTR(obj));
+                    rb_shape_set_too_complex(obj);
+                    RUBY_ASSERT(rb_shape_obj_too_complex(obj));
 
-            RB_OBJ_WRITE(obj, &RCLASS_IVPTR(obj)[idx], value);
-            rb_shape_set_shape(obj, shape);
+                    if (RCLASS_IVPTR(obj)) {
+                        xfree(RCLASS_IVPTR(obj));
+                    }
+
+                    RCLASS_EXT(obj)->iv_ptr = (VALUE *)table;
+                }
+                else {
+                    // We always allocate a power of two sized IV array. This way we
+                    // only need to realloc when we expand into a new power of two size
+                    if ((idx & (idx - 1)) == 0) {
+                        size_t newsize = idx ? idx * 2 : 1;
+                        REALLOC_N(RCLASS_IVPTR(obj), VALUE, newsize);
+                    }
+
+                    RUBY_ASSERT(RCLASS_IVPTR(obj));
+
+                    RB_OBJ_WRITE(obj, &RCLASS_IVPTR(obj)[idx], value);
+                    rb_shape_set_shape(obj, shape);
+                }
+            }
         }
     }
     RB_VM_LOCK_LEAVE();