That function is a bit too low level to called from multiple
places. It's always used in tandem with `rb_shape_set_too_complex`
and both have to know how the object is laid out to update the
`iv_ptr`.
So instead we can provide two higher level function:
- `rb_obj_copy_ivs_to_hash_table` to prepare a `st_table` from an
arbitrary oject.
- `rb_obj_convert_to_too_complex` to assign the new `st_table`
to the old object, and safely free the old `iv_ptr`.
Unfortunately both can't be combined into one, because `rb_obj_copy_ivar`
need `rb_obj_copy_ivs_to_hash_table` to copy from one object
to another.
It's only used to allocate the table with the right size,
but in some case we were passing `rb_shape_get_shape_by_id(SHAPE_OBJ_TOO_COMPLEX)`
which `next_iv_index` is a bit undefined.
So overall we're better to just allocate a table the size of the existing
object, it should be close enough in the vast majority of cases,
and that's already a de-optimizaton path anyway.
Right now the `rb_shape_get_next` shape caller need to
first check if there is capacity left, and if not call
`rb_shape_transition_shape_capa` before it can call `rb_shape_get_next`.
And on each of these it needs to checks if we got a TOO_COMPLEX
back.
All this logic is duplicated in the interpreter, YJIT and RJIT.
Instead we can have `rb_shape_get_next` do the capacity transition
when needed. The caller can compare the old and new shapes capacity
to know if resizing is needed. It also can check for TOO_COMPLEX
only once.
... because GCC 13 warns it.
```
In file included from class.c:24:
In function ‘RCLASS_SET_ALLOCATOR’,
inlined from ‘class_alloc’ at class.c:251:5,
inlined from ‘rb_module_s_alloc’ at class.c:1045:17:
internal/class.h:159:43: warning: array subscript 0 is outside array bounds of ‘rb_classext_t[0]’ {aka ‘struct rb_classext_struct[]’} [-Warray-bounds=]
159 | RCLASS_EXT(klass)->as.class.allocator = allocator;
| ^
```
https://rubyci.s3.amazonaws.com/arch/ruby-master/log/20231015T030003Z.log.html.gz
This patch introduce M:N thread scheduler for Ractor system.
In general, M:N thread scheduler employs N native threads (OS threads)
to manage M user-level threads (Ruby threads in this case).
On the Ruby interpreter, 1 native thread is provided for 1 Ractor
and all Ruby threads are managed by the native thread.
From Ruby 1.9, the interpreter uses 1:1 thread scheduler which means
1 Ruby thread has 1 native thread. M:N scheduler change this strategy.
Because of compatibility issue (and stableness issue of the implementation)
main Ractor doesn't use M:N scheduler on default. On the other words,
threads on the main Ractor will be managed with 1:1 thread scheduler.
There are additional settings by environment variables:
`RUBY_MN_THREADS=1` enables M:N thread scheduler on the main ractor.
Note that non-main ractors use the M:N scheduler without this
configuration. With this configuration, single ractor applications
run threads on M:1 thread scheduler (green threads, user-level threads).
`RUBY_MAX_CPU=n` specifies maximum number of native threads for
M:N scheduler (default: 8).
This patch will be reverted soon if non-easy issues are found.
[Bug #19842]
This commit moves IO#readline to Ruby. In order to call C functions,
keyword arguments must be converted to hashes. Prior to this commit,
code like `io.readline(chomp: true)` would allocate a hash. This
commits moves the keyword "denaturing" to Ruby, allowing us to send
positional arguments to the C API and avoiding the hash allocation.
Here is an allocation benchmark for the method:
```
x = GC.stat(:total_allocated_objects)
File.open("/usr/share/dict/words") do |f|
f.readline(chomp: true) until f.eof?
end
p ALLOCATIONS: GC.stat(:total_allocated_objects) - x
```
Before this commit, the output was this:
```
$ make run
./miniruby -I./lib -I. -I.ext/common -r./arm64-darwin22-fake ./test.rb
{:ALLOCATIONS=>707939}
```
Now it is this:
```
$ make run
./miniruby -I./lib -I. -I.ext/common -r./arm64-darwin22-fake ./test.rb
{:ALLOCATIONS=>471962}
```
[Bug #19890] [ruby-core:114803]
If we're during incremental marking, then Ruby code can execute that
deallocates certain memory buffers that have been called with
rb_gc_mark_weak, which can cause use-after-free bugs.
Previously we used the next character following the found prefix to
determine if the match ended on a broken character.
This had caused surprising behaviour when a valid character was followed
by a UTF-8 continuation byte.
This commit changes the behaviour to instead look for the end of the
last character in the prefix.
[Bug #19784]
Co-authored-by: ywenc <ywenc@github.com>
Co-authored-by: Nobuyoshi Nakada <nobu@ruby-lang.org>
This is an internal only function not exposed to the C extension API.
It's only use so far is from rb_vm_mark, where it's used to mark the
values in the vm->trap_list.cmd array.
There shouldn't be any reason why these cannot move.
This commit allows them to move by updating their references during the
reference updating step of compaction.
To do this we've introduced another internal function
rb_gc_update_values as a partner to rb_gc_mark_values.
This allows us to refactor rb_gc_mark_values to not pin
[Feature #19783]
This commit adds support for weak references in the GC through the
function `rb_gc_mark_weak`. Unlike strong references, weak references
does not mark the object, but rather lets the GC know that an object
refers to another one. If the child object is freed, the pointer from
the parent object is overwritten with `Qundef`.
Co-Authored-By: Jean Boussier <byroot@ruby-lang.org>
[Feature #18885]
For now, the optimizations performed are:
- Run a major GC
- Compact the heap
- Promote all surviving objects to oldgen
Other optimizations may follow.
Introduce Universal Parser mode for the parser.
This commit includes these changes:
* Introduce `UNIVERSAL_PARSER` macro. All of CRuby related functions
are passed via `struct rb_parser_config_struct` when this macro is enabled.
* Add CI task with 'cppflags=-DUNIVERSAL_PARSER' for ubuntu.