Refactor rb_shape_transition_remove_ivar

Move the fields management logic in `rb_ivar_delete`, and keep
shape managment logic in `rb_shape_transition_remove_ivar`.
This commit is contained in:
Jean Boussier 2025-05-23 15:55:38 +02:00
parent 746d7fef92
commit 52da5f8bbc
Notes: git 2025-05-23 15:33:33 +00:00
3 changed files with 70 additions and 55 deletions

57
shape.c
View File

@ -632,62 +632,21 @@ remove_shape_recursive(rb_shape_t *shape, ID id, rb_shape_t **removed_shape)
}
}
bool
rb_shape_transition_remove_ivar(VALUE obj, ID id, VALUE *removed)
shape_id_t
rb_shape_transition_remove_ivar(VALUE obj, ID id, shape_id_t *removed_shape_id)
{
rb_shape_t *shape = rb_obj_shape(obj);
shape_id_t shape_id = rb_obj_shape_id(obj);
rb_shape_t *shape = RSHAPE(shape_id);
if (UNLIKELY(rb_shape_too_complex_p(shape))) {
return false;
}
RUBY_ASSERT(!rb_shape_too_complex_p(shape));
rb_shape_t *removed_shape = NULL;
rb_shape_t *new_shape = remove_shape_recursive(shape, id, &removed_shape);
if (new_shape) {
RUBY_ASSERT(removed_shape != NULL);
if (UNLIKELY(rb_shape_too_complex_p(new_shape))) {
return false;
}
RUBY_ASSERT(new_shape->next_field_index == shape->next_field_index - 1);
VALUE *fields;
switch(BUILTIN_TYPE(obj)) {
case T_CLASS:
case T_MODULE:
fields = RCLASS_PRIME_FIELDS(obj);
break;
case T_OBJECT:
fields = ROBJECT_FIELDS(obj);
break;
default: {
struct gen_fields_tbl *fields_tbl;
rb_gen_fields_tbl_get(obj, id, &fields_tbl);
fields = fields_tbl->as.shape.fields;
break;
}
}
*removed = fields[removed_shape->next_field_index - 1];
memmove(&fields[removed_shape->next_field_index - 1], &fields[removed_shape->next_field_index],
((new_shape->next_field_index + 1) - removed_shape->next_field_index) * sizeof(VALUE));
// Re-embed objects when instances become small enough
// This is necessary because YJIT assumes that objects with the same shape
// have the same embeddedness for efficiency (avoid extra checks)
if (BUILTIN_TYPE(obj) == T_OBJECT &&
!RB_FL_TEST_RAW(obj, ROBJECT_EMBED) &&
rb_obj_embedded_size(new_shape->next_field_index) <= rb_gc_obj_slot_size(obj)) {
RB_FL_SET_RAW(obj, ROBJECT_EMBED);
memcpy(ROBJECT_FIELDS(obj), fields, new_shape->next_field_index * sizeof(VALUE));
xfree(fields);
}
rb_shape_set_shape(obj, new_shape);
*removed_shape_id = rb_shape_id(removed_shape);
return rb_shape_id(new_shape);
}
return true;
return shape_id;
}
shape_id_t

View File

@ -168,7 +168,7 @@ bool rb_shape_id_too_complex_p(shape_id_t shape_id);
void rb_shape_set_shape(VALUE obj, rb_shape_t *shape);
shape_id_t rb_shape_transition_frozen(VALUE obj);
shape_id_t rb_shape_transition_complex(VALUE obj);
bool rb_shape_transition_remove_ivar(VALUE obj, ID id, VALUE *removed);
shape_id_t rb_shape_transition_remove_ivar(VALUE obj, ID id, shape_id_t *removed_shape_id);
shape_id_t rb_shape_transition_add_ivar(VALUE obj, ID id);
shape_id_t rb_shape_transition_add_ivar_no_warnings(VALUE obj, ID id);
shape_id_t rb_shape_transition_object_id(VALUE obj);

View File

@ -1542,11 +1542,68 @@ rb_ivar_delete(VALUE obj, ID id, VALUE undef)
IVAR_ACCESSOR_SHOULD_BE_MAIN_RACTOR(id);
}
if (!rb_shape_transition_remove_ivar(obj, id, &val)) {
if (!rb_shape_obj_too_complex_p(obj)) {
rb_evict_fields_to_hash(obj);
}
shape_id_t old_shape_id = rb_obj_shape_id(obj);
if (rb_shape_id_too_complex_p(old_shape_id)) {
goto too_complex;
}
shape_id_t removed_shape_id = 0;
shape_id_t next_shape_id = rb_shape_transition_remove_ivar(obj, id, &removed_shape_id);
if (next_shape_id == old_shape_id) {
return undef;
}
if (UNLIKELY(rb_shape_id_too_complex_p(next_shape_id))) {
rb_evict_fields_to_hash(obj);
goto too_complex;
}
RUBY_ASSERT(RSHAPE(next_shape_id)->next_field_index == RSHAPE(old_shape_id)->next_field_index - 1);
VALUE *fields;
switch(BUILTIN_TYPE(obj)) {
case T_CLASS:
case T_MODULE:
fields = RCLASS_PRIME_FIELDS(obj);
break;
case T_OBJECT:
fields = ROBJECT_FIELDS(obj);
break;
default: {
struct gen_fields_tbl *fields_tbl;
rb_gen_fields_tbl_get(obj, id, &fields_tbl);
fields = fields_tbl->as.shape.fields;
break;
}
}
RUBY_ASSERT(removed_shape_id != INVALID_SHAPE_ID);
attr_index_t new_fields_count = RSHAPE(next_shape_id)->next_field_index;
attr_index_t removed_index = RSHAPE(removed_shape_id)->next_field_index - 1;
val = fields[removed_index];
size_t trailing_fields = new_fields_count - removed_index;
MEMMOVE(&fields[removed_index], &fields[removed_index + 1], VALUE, trailing_fields);
if (RB_TYPE_P(obj, T_OBJECT) &&
!RB_FL_TEST_RAW(obj, ROBJECT_EMBED) &&
rb_obj_embedded_size(new_fields_count) <= rb_gc_obj_slot_size(obj)) {
// Re-embed objects when instances become small enough
// This is necessary because YJIT assumes that objects with the same shape
// have the same embeddedness for efficiency (avoid extra checks)
RB_FL_SET_RAW(obj, ROBJECT_EMBED);
MEMCPY(ROBJECT_FIELDS(obj), fields, VALUE, new_fields_count);
xfree(fields);
}
rb_shape_set_shape_id(obj, next_shape_id);
return val;
too_complex:
{
st_table *table = NULL;
switch (BUILTIN_TYPE(obj)) {
case T_CLASS:
@ -1573,7 +1630,6 @@ rb_ivar_delete(VALUE obj, ID id, VALUE undef)
}
}
}
return val;
}