Get rid of FL_EXIVAR

Now that the shape_id gives us all the same information, it's no
longer needed.

Author: byroot

bootstraptest/test_yjit.rb

@@ -220,7 +220,7 @@ class Sub < String; end
   call(Sub.new('o')).class
 }
 
-# String#dup with FL_EXIVAR
+# String#dup with generic ivars
 assert_equal '["str", "ivar"]', %q{
   def str_dup(str) = str.dup
   str = "str"

gc.c

@@ -4010,8 +4010,6 @@ vm_weak_table_gen_fields_foreach(st_data_t key, st_data_t value, st_data_t data)
 
       case ST_DELETE:
         free_gen_fields_tbl((VALUE)key, (struct gen_fields_tbl *)value);
-
-        FL_UNSET((VALUE)key, FL_EXIVAR);
         RBASIC_SET_SHAPE_ID((VALUE)key, ROOT_SHAPE_ID);
         return ST_DELETE;
 

include/ruby/internal/fl_type.h

@@ -248,6 +248,21 @@ ruby_fl_type {
     RBIMPL_ATTR_DEPRECATED(("taintedness turned out to be a wrong idea."))
 #elif defined(_MSC_VER)
 # pragma deprecated(RUBY_FL_TAINT)
+#endif
+
+                         = 0,
+
+    /**
+     * @deprecated  This flag was an implementation detail that should never have
+     *              no been exposed. Exists  here for  backwards
+     *              compatibility only.  You can safely forget about it.
+     */
+    RUBY_FL_EXIVAR
+
+#if defined(RBIMPL_HAVE_ENUM_ATTRIBUTE)
+    RBIMPL_ATTR_DEPRECATED(("FL_EXIVAR is an outdated implementation detail, it shoudl be used."))
+#elif defined(_MSC_VER)
+# pragma deprecated(RUBY_FL_EXIVAR)
 #endif
 
                          = 0,
@@ -286,18 +301,12 @@ ruby_fl_type {
     */
     RUBY_FL_UNUSED9  = (1<<9),
 
-    /**
-     * This flag has something to do with instance variables.  3rd parties need
-     * not  know, but  there are  several ways  to store  an object's  instance
-     * variables.   Objects  with this  flag  use  so-called "generic"  backend
-     * storage.  This  distinction is purely an  implementation detail.  People
-     * need not be aware of this working behind-the-scene.
-     *
-     * @internal
-     *
-     * As of writing everything except ::RObject and RModule use this scheme.
-     */
-    RUBY_FL_EXIVAR       = (1<<10),
+   /**
+    * This flag is no longer in use
+    *
+    * @internal
+    */
+    RUBY_FL_UNUSED10 = (1<<10),
 
     /**
      * This flag has something to do with data immutability.  When this flag is
@@ -399,7 +408,7 @@ enum {
 # pragma deprecated(RUBY_FL_DUPPED)
 #endif
 
-    = (int)RUBY_T_MASK | (int)RUBY_FL_EXIVAR
+    = (int)RUBY_T_MASK
 };
 
 #undef RBIMPL_HAVE_ENUM_ATTRIBUTE

misc/lldb_rb/commands/print_flags_command.py

@@ -17,7 +17,7 @@ def call(self, debugger, command, exe_ctx, result):
 
         flags = [
             "RUBY_FL_WB_PROTECTED", "RUBY_FL_PROMOTED", "RUBY_FL_FINALIZE",
-            "RUBY_FL_SHAREABLE", "RUBY_FL_EXIVAR", "RUBY_FL_FREEZE",
+            "RUBY_FL_SHAREABLE", "RUBY_FL_FREEZE",
             "RUBY_FL_USER0", "RUBY_FL_USER1", "RUBY_FL_USER2", "RUBY_FL_USER3", "RUBY_FL_USER4",
             "RUBY_FL_USER5", "RUBY_FL_USER6", "RUBY_FL_USER7", "RUBY_FL_USER8", "RUBY_FL_USER9",
             "RUBY_FL_USER10", "RUBY_FL_USER11", "RUBY_FL_USER12", "RUBY_FL_USER13", "RUBY_FL_USER14",

rubyparser.h

@@ -1153,7 +1153,7 @@ typedef struct RNode_ERROR {
 #define RNODE_FILE(node) ((rb_node_file_t *)(node))
 #define RNODE_ENCODING(node) ((rb_node_encoding_t *)(node))
 
-/* FL     : 0..4: T_TYPES, 5: KEEP_WB, 6: PROMOTED, 7: FINALIZE, 8: UNUSED, 9: UNUSED, 10: EXIVAR, 11: FREEZE */
+/* FL     : 0..4: T_TYPES, 5: KEEP_WB, 6: PROMOTED, 7: FINALIZE, 8..10: UNUSED, 11: FREEZE */
 /* NODE_FL: 0..4: UNUSED,  5: UNUSED,  6: UNUSED,   7: NODE_FL_NEWLINE,
  *          8..14: nd_type,
  *          15..: nd_line

shape.c

@@ -1266,13 +1266,6 @@ rb_shape_verify_consistency(VALUE obj, shape_id_t shape_id)
         }
     }
 
-    if (FL_TEST_RAW(obj, FL_EXIVAR)) {
-        RUBY_ASSERT(rb_obj_exivar_p(obj));
-    }
-    else {
-        RUBY_ASSERT(!rb_obj_exivar_p(obj));
-    }
-
     return true;
 }
 #endif

string.c

@@ -485,7 +485,6 @@ build_fstring(VALUE str, struct fstr_update_arg *arg)
     RUBY_ASSERT(RB_TYPE_P(str, T_STRING));
     RUBY_ASSERT(OBJ_FROZEN(str));
     RUBY_ASSERT(!FL_TEST_RAW(str, STR_FAKESTR));
-    RUBY_ASSERT(!FL_TEST_RAW(str, FL_EXIVAR));
     RUBY_ASSERT(!rb_obj_exivar_p(str));
     RUBY_ASSERT(RBASIC_CLASS(str) == rb_cString);
     RUBY_ASSERT(!rb_objspace_garbage_object_p(str));

variable.c

@@ -1271,7 +1271,6 @@ rb_free_generic_ivar(VALUE obj)
                 xfree(fields_tbl);
             }
         }
-        FL_UNSET_RAW(obj, FL_EXIVAR);
         RBASIC_SET_SHAPE_ID(obj, ROOT_SHAPE_ID);
     }
 }
@@ -1329,7 +1328,6 @@ rb_obj_field_get(VALUE obj, shape_id_t target_shape_id)
             fields_hash = ROBJECT_FIELDS_HASH(obj);
             break;
           default:
-            RUBY_ASSERT(FL_TEST_RAW(obj, FL_EXIVAR));
             RUBY_ASSERT(rb_obj_exivar_p(obj));
             struct gen_fields_tbl *fields_tbl = NULL;
             rb_ivar_generic_fields_tbl_lookup(obj, &fields_tbl);
@@ -1361,7 +1359,6 @@ rb_obj_field_get(VALUE obj, shape_id_t target_shape_id)
         fields = ROBJECT_FIELDS(obj);
         break;
       default:
-        RUBY_ASSERT(FL_TEST_RAW(obj, FL_EXIVAR));
         RUBY_ASSERT(rb_obj_exivar_p(obj));
         struct gen_fields_tbl *fields_tbl = NULL;
         rb_ivar_generic_fields_tbl_lookup(obj, &fields_tbl);
@@ -1839,9 +1836,6 @@ generic_fields_lookup_ensure_size(st_data_t *k, st_data_t *v, st_data_t u, int e
             RUBY_ASSERT(RSHAPE_TYPE_P(fields_lookup->shape_id, SHAPE_IVAR) || RSHAPE_TYPE_P(fields_lookup->shape_id, SHAPE_OBJ_ID));
             RUBY_ASSERT(RSHAPE_CAPACITY(RSHAPE_PARENT(fields_lookup->shape_id)) < RSHAPE_CAPACITY(fields_lookup->shape_id));
         }
-        else {
-            FL_SET_RAW((VALUE)*k, FL_EXIVAR);
-        }
 
         fields_tbl = gen_fields_tbl_resize(fields_tbl, RSHAPE_CAPACITY(fields_lookup->shape_id));
         *v = (st_data_t)fields_tbl;
@@ -1852,7 +1846,6 @@ generic_fields_lookup_ensure_size(st_data_t *k, st_data_t *v, st_data_t u, int e
         rb_obj_set_shape_id(fields_lookup->obj, fields_lookup->shape_id);
     }
 
-    RUBY_ASSERT(FL_TEST((VALUE)*k, FL_EXIVAR));
     RUBY_ASSERT(rb_obj_exivar_p((VALUE)*k));
 
     return ST_CONTINUE;
@@ -1869,8 +1862,6 @@ generic_ivar_set_shape_fields(VALUE obj, void *data)
         st_update(generic_fields_tbl(obj, fields_lookup->id, false), (st_data_t)obj, generic_fields_lookup_ensure_size, (st_data_t)fields_lookup);
     }
 
-    FL_SET_RAW(obj, FL_EXIVAR);
-
     return fields_lookup->fields_tbl->as.shape.fields;
 }
 
@@ -1893,7 +1884,6 @@ generic_ivar_set_set_shape_id(VALUE obj, shape_id_t shape_id, void *data)
 static shape_id_t
 generic_ivar_set_transition_too_complex(VALUE obj, void *_data)
 {
-    FL_SET_RAW(obj, FL_EXIVAR);
     shape_id_t new_shape_id = rb_evict_fields_to_hash(obj);
     return new_shape_id;
 }
@@ -1911,8 +1901,6 @@ generic_ivar_set_too_complex_table(VALUE obj, void *data)
         RB_VM_LOCKING() {
             st_insert(generic_fields_tbl(obj, fields_lookup->id, false), (st_data_t)obj, (st_data_t)fields_tbl);
         }
-
-        FL_SET_RAW(obj, FL_EXIVAR);
     }
 
     RUBY_ASSERT(rb_shape_obj_too_complex_p(obj));
@@ -2368,8 +2356,6 @@ rb_copy_generic_ivar(VALUE dest, VALUE obj)
         if (gen_fields_tbl_count(obj, obj_fields_tbl) == 0)
             goto clear;
 
-        FL_SET(dest, FL_EXIVAR);
-
         if (rb_shape_too_complex_p(src_shape_id)) {
             rb_shape_copy_complex_ivars(dest, obj, src_shape_id, obj_fields_tbl->as.complex.table);
             return;
@@ -2393,7 +2379,6 @@ rb_copy_generic_ivar(VALUE dest, VALUE obj)
 
         if (!RSHAPE_LEN(dest_shape_id)) {
             rb_obj_set_shape_id(dest, dest_shape_id);
-            FL_UNSET(dest, FL_EXIVAR);
             return;
         }
 
@@ -2424,15 +2409,10 @@ rb_copy_generic_ivar(VALUE dest, VALUE obj)
 void
 rb_replace_generic_ivar(VALUE clone, VALUE obj)
 {
-    RUBY_ASSERT(FL_TEST(obj, FL_EXIVAR));
-
     RB_VM_LOCKING() {
         st_data_t fields_tbl, obj_data = (st_data_t)obj;
         if (st_delete(generic_fields_tbl_, &obj_data, &fields_tbl)) {
-            FL_UNSET_RAW(obj, FL_EXIVAR);
-
             st_insert(generic_fields_tbl_, (st_data_t)clone, fields_tbl);
-            FL_SET_RAW(clone, FL_EXIVAR);
         }
         else {
             rb_bug("unreachable");