This patch is part of universal parser work.
## Summary
- Decouple VALUE from members below:
- `(struct parser_params *)->debug_lines`
- `(rb_ast_t *)->body.script_lines`
- Instead, they are now `rb_parser_ary_t *`
- They can also be a `(VALUE)FIXNUM` as before to hold line count
- `ISEQ_BODY(iseq)->variable.script_lines` remains VALUE
- In order to do this,
- Add `VALUE script_lines` param to `rb_iseq_new_with_opt()`
- Introduce `rb_parser_build_script_lines_from()` to convert `rb_parser_ary_t *` into `VALUE`
## Other details
- Extend `rb_parser_ary_t *`. It previously could only store `rb_parser_ast_token *`, now can store script_lines, too
- Change tactics of building the top-level `SCRIPT_LINES__` in `yycompile0()`
- Before: While parsing, each line of the script is added to `SCRIPT_LINES__[path]`
- After: After `yyparse(p)`, `SCRIPT_LINES__[path]` will be built from `p->debug_lines`
- Remove the second parameter of `rb_parser_set_script_lines()` to make it simple
- Introduce `script_lines_free()` to be called from `rb_ast_free()` because the GC no longer takes care of the script_lines
- Introduce `rb_parser_string_deep_copy()` in parse.y to maintain script_lines when `rb_ruby_parser_free()` called
- With regard to this, please see *Future tasks* below
## Future tasks
- Decouple IMEMO from `rb_ast_t *`
- This lifts the five-members-restriction of Ruby object,
- So we will be able to move the ownership of the `lex.string_buffer` from parser to AST
- Then we remove `rb_parser_string_deep_copy()` to make the whole thing simple
We don't need to check that the object is pointer to the GC heap in
vm_ccs_free because it is called during sweeping, which does not free
pages so it can never point to an object that is not on the GC heap.
We don't need to check that the object is pointer to the GC heap in
moved_or_living_object_strictly_p because it is called during reference
updating, which does not free pages so it can never point to an object
that is not on the GC heap.
HASUMI Hitoshi
Peter Zhu