This `st_table` is used to both mark and pin classes
defined from the C API. But `vm->mark_object_ary` already
does both much more efficiently.
Currently a Ruby process starts with 252 rooted classes,
which uses `7224B` in an `st_table` or `2016B` in an `RArray`.
So a baseline of 5kB saved, but since `mark_object_ary` is
preallocated with `1024` slots but only use `405` of them,
it's a net `7kB` save.
`vm->mark_object_ary` is also being refactored.
Prior to this changes, `mark_object_ary` was a regular `RArray`, but
since this allows for references to be moved, it was marked a second
time from `rb_vm_mark()` to pin these objects.
This has the detrimental effect of marking these references on every
minors even though it's a mostly append only list.
But using a custom TypedData we can save from having to mark
all the references on minor GC runs.
Addtionally, immediate values are now ignored and not appended
to `vm->mark_object_ary` as it's just wasted space.
rb_class_get_superclass returns the immediate SUPER, including T_ICLASS.
rb_ivar_lookup isn't implemented for T_ICLASS so it uses the default
behaviour, which always returns Qnil.
This commit avoids checking T_ICLASS for ivars.
* memory_view.c: remove a reference in view->obj at rb_memory_view_release
* memory_view.c: keep references of memory-view-exported objects
* Update common.mk
* memory_view.c: Use st_update
* Add buffer protocol
* Modify for some review comments
* Per-object buffer availability
* Rename to MemoryView from Buffer and make compilable
* Support integral repeat count in memory view format
* Support 'x' for padding bytes
* Add rb_memory_view_parse_item_format
* Check type in rb_memory_view_register
* Update dependencies in common.mk
* Add test of MemoryView
* Add test of rb_memory_view_init_as_byte_array
* Add native size format test
* Add MemoryView test utilities
* Add test of rb_memory_view_fill_contiguous_strides
* Skip spaces in format string
* Support endianness specifiers
* Update documentation
* Support alignment
* Use RUBY_ALIGNOF
* Fix format parser to follow the pack format
* Support the _ modifier
* Parse count specifiers in get_format_size function.
* Use STRUCT_ALIGNOF
* Fix test
* Fix test
* Fix total size for the case with tail padding
* Fix rb_memory_view_get_item_pointer
* Fix rb_memory_view_parse_item_format again
Jean Boussier
Peter Zhu
Takashi Kokubun
John Hawthorn
Kenta Murata
Nobuyoshi Nakada
Benoit Daloze
Ryuta Kamizono
Kenta Murata
卜部昌平