Now the method tables (in classes/modules and caches) keeps C function
pointers without wrapping in `struct RProc` objects. For the sake of
portability, `mrb_method_t` is represented by the struct and union, but
if the most significant bit of the pointer is not used by the platform,
`mrb_method_t` should be packed in `uintptr_t` to reduce memory usage.
`MRB_METHOD_TABLE_INLINE` is turned on by default for linux.
To enable method cache, define `MRB_METHOD_CACHE` or
`MRB_METHOD_CACHE_SIZE`. The cache size must be power of 2.
The default cache size is 128.
The measurement:
I measured simple benchmarks found in benchmark/ directory. With
method cache enabled, we gained 6-8% performance improvement, with
97-99% cache hit rate.
The change removes several internal instance variables used by
class name management. The variables `__classid__` and `__classpath__`
are no longer available. `__outer__` is used only for unnamed outer
classes/modules (and will be removed after they are named).
[Important note]
Along with this change we removed several public functions.
- mrb_class_outer_module()
- mrb_class_sym()
We believe no one have used those functions, but if you do, please
ask us for the workaround.
It isn't needed as it's very similar to mrb_define_method_raw() and also
there's only one place where mrb_proc_ptr() actually has to be called.
Inspired by @furunkel's method cache patch (#2764).
One of the biggest set of changes needed to make C++ compile, is that you
can't autoconvert "void*" to a different pointer type without a cast (you
can of course, convert pointers *to* "void*"!)
For the first part, convert the users of "mrb_obj_alloc". Since it has
to return something, make it RBasic* (that's what mrb_obj_alloc() is
operating on anyway). This way, even in C you'll get a warning if you
don't cast it.
For places where there are a lot of similar calls to mrb_obj_alloc(),
this can be easily hidden through a macro. I did this in string.c:
#define mrb_obj_alloc_string(mrb) ((struct RString *) mrb_obj_alloc((mrb), MRB_TT_STRING, (mrb)->string_class))
I also updated the mrb_object() macro to also return a RBasic* -- my
previous commit changed that from "void*" -> "RObject*", but I figure
it should be consistent with mrb_obj_alloc()