Instead of `irep` links, we added a `upper` link to `struct RProc`.
To make a space for the `upper` link, we moved `target_class` reference.
If a `Proc` does not have `env`, `target_class` is saved in an `union`
shared with `env` (if a `Proc` has env, you can tell it by `MRB_PROC_ENV_P()).
Otherwise `target_class` is referenced from `env->c`. We removed links
in `env` as well.
This change removes 2 members from `mrb_irep` struct, thus saving 2
words per method/proc/block. This also fixes potential memory leaks
due to the circular references caused by a link from `mrb_irep`.
Instead of `irep -> proc` chain, we use `irep -> irep` chain to
avoid GC bugs like #3804. We added `target_class` reference to
`mrb_irep` struct. That means one more word consumption per `irep`.
Instead of preserving a backtrace in `mrb_state`, `mrb_exc_set`
keeps packed backtrace in an exception object. `#backtrace` unpacks
it to an array of strings.
GitHub: fix#2902, #2917
The current implementation traverses stack to retrieve backtrace. But
stack will be changed when some operations are occurred. It means that
backtrace may be broken after some operations.
This change (1) saves the minimum information to retrieve backtrace when
exception is raised and (2) restores backtrace from the minimum
information when backtrace is needed. It reduces overhead for creating
backtrace Ruby objects.
The space for the minimum information is reused by multiple
exceptions. So memory allocation isn't occurred for each exception.
Sometimes it is very useful just return from mrb_close if NULL is
passed as mrb. This is the same spirit of free(3), which just does
nothing if NULL is passed.
Adds following macros:
* MRB_FIXED_STATE_ATEXIT_STACK (not defined by default)
* When defined enables fixed state atexit stack.
* MRB_FIXED_STATE_ATEXIT_STACK_SIZE (default value: 5)
* This macro will be ignored when `MRB_FIXED_STATE_ATEXIT_STACK` isn't defined.
* When `mrb_state_atexit` is called more than this value it will raise runtime error.
- reduce compile time by a little bit (full-core: ~0.7s for me)
- thanks to 'include-what-you-use' for some help
- include Standard C header files before any other (coding style)
YAMAMOTO Masaya