Extract yjit_force_iv_index and make it work when object is frozen
In an effort to simplify the logic YJIT generates for accessing instance variable, YJIT ensures that a given name-to-index mapping exists at compile time. In the case that the mapping doesn't exist, it was created by using rb_ivar_set() with Qundef on the sample object we see at compile time. This hack isn't fine if the sample object happens to be frozen, in which case YJIT would raise a FrozenError unexpectedly.
To deal with this, make a new function that only reserves the mapping but doesn't touch the object. This is rb_obj_ensure_iv_index_mapping(). This new function superceeds the functionality of rb_iv_index_tbl_lookup() so it was removed.
Added by alanwu (Alan Wu) about 4 years ago
Extract yjit_force_iv_index and make it work when object is frozen
In an effort to simplify the logic YJIT generates for accessing instance
variable, YJIT ensures that a given name-to-index mapping exists at
compile time. In the case that the mapping doesn't exist, it was created
by using rb_ivar_set() with Qundef on the sample object we see at
compile time. This hack isn't fine if the sample object happens to be
frozen, in which case YJIT would raise a FrozenError unexpectedly.
To deal with this, make a new function that only reserves the mapping
but doesn't touch the object. This is rb_obj_ensure_iv_index_mapping().
This new function superceeds the functionality of rb_iv_index_tbl_lookup()
so it was removed.
Reported by and includes a test case from John Hawthorn john@hawthorn.email
Fixes: GH-282