Previously, passing objects that respond to #to_int to `String#setbyte`
resulted in a crash when compiled by YJIT. This was due to the lazily
pushed frame from rb_yjit_lazy_push_frame() lingering and not being
popped by an exception as expected.
The fix is to ensure that `ec->cfp` is restored to before the lazy frame
push in case the method call for conversion succeeds. Right now, this is
only for conversion to integers.
Found running `ruby/spec`.
* clarify comment
We just need to make sure `ec->cfp` is always preserved and this can
convert without rising when `raise` is true.
This PR moves `rb_copy_wb_protected_attribute` and
`rb_gc_copy_finalizer` into a single function called
`rb_gc_copy_attributes` to be called by `init_copy`. This reduces the
surface area of the GC API.
Co-authored-by: Peter Zhu <peter@peterzhu.ca>
[Feature #20205]
As a path toward enabling frozen string literals by default in the future,
this commit introduce "chilled strings". From a user perspective chilled
strings pretend to be frozen, but on the first attempt to mutate them,
they lose their frozen status and emit a warning rather than to raise a
`FrozenError`.
Implementation wise, `rb_compile_option_struct.frozen_string_literal` is
no longer a boolean but a tri-state of `enabled/disabled/unset`.
When code is compiled with frozen string literals neither explictly enabled
or disabled, string literals are compiled with a new `putchilledstring`
instruction. This instruction is identical to `putstring` except it marks
the String with the `STR_CHILLED (FL_USER3)` and `FL_FREEZE` flags.
Chilled strings have the `FL_FREEZE` flag as to minimize the need to check
for chilled strings across the codebase, and to improve compatibility with
C extensions.
Notes:
- `String#freeze`: clears the chilled flag.
- `String#-@`: acts as if the string was mutable.
- `String#+@`: acts as if the string was mutable.
- `String#clone`: copies the chilled flag.
Co-authored-by: Jean Boussier <byroot@ruby-lang.org>
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.
This frees FL_USER0 on both T_MODULE and T_CLASS.
Note: prior to this, FL_SINGLETON was never set on T_MODULE,
so checking for `FL_SINGLETON` without first checking that
`FL_TYPE` was `T_CLASS` was valid. That's no longer the case.
* YJIT: Lazily push a frame for specialized C funcs
Co-authored-by: Maxime Chevalier-Boisvert <maxime.chevalierboisvert@shopify.com>
* Fix a comment on pc_to_cfunc
* Rename rb_yjit_check_pc to rb_yjit_lazy_push_frame
* Rename it to jit_prepare_lazy_frame_call
* Fix a typo
* Optimize String#getbyte as well
* Optimize String#byteslice as well
---------
Co-authored-by: Maxime Chevalier-Boisvert <maxime.chevalierboisvert@shopify.com>
[Bug #20253]
All the way down to Ruby 1.9, `Proc`, `Method`, `UnboundMethod`
and `Binding` always had their own specific clone and dup routine.
This caused various discrepancies with how other objects behave
on `dup` and `clone. [Bug #20250], [Bug #20253].
This commit get rid of `CLONESETUP` and use the the same codepath
as all other types, so ensure consistency.
NB: It's still not accepting the `freeze` keyword argument on `clone`.
Co-Authored-By: Étienne Barrié <etienne.barrie@gmail.com>
[Bug #20162]
Creating a ST table then calling st_replace leaks memory because the
st_replace overwrites the ST table without freeing any of the existing
memory. This commit changes it to use st_copy instead.
For example:
RubyVM::Shape.exhaust_shapes
o = Object.new
o.instance_variable_set(:@a, 0)
10.times do
100_000.times { o.dup }
puts `ps -o rss= -p #{$$}`
end
Before:
23264
33600
42672
52160
61600
71728
81056
90528
100560
109840
After:
14752
14816
15584
15584
15664
15664
15664
15664
15664
15664
RUBY_FL_PROMOTED is used by the garbage collector to track when an
object becomes promoted to the old generation. rb_obj_setup must not
copy that flag over because then it may become out-of-sync with the age
of the object.
This fixes a bug in Method#clone where the cloned Method object may get
RUBY_FL_PROMOTED incorrectly set.
Objects with the same shape must always have the same "embeddedness"
(either embedded or heap allocated) because YJIT assumes so. However,
using remove_instance_variable, it's possible that some objects are
embedded and some are heap allocated because it does not re-embed heap
allocated objects.
This commit changes remove_instance_variable to re-embed Object
instance variables when it becomes small enough.
For this public API, the callback is declared to take
`(ID, VALUE, st_data_t)`, but it so happens that using
`(st_data_t, st_data_t, st_data_t)` also
type checks, because the underlying type is identical.
Use it as declared and get rid of some casts.
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.
st tables will maintain insertion order so we can marshal dump / load
objects with instance variables in the same order they were set on that
particular instance
[ruby-core:112926] [Bug #19535]
Co-Authored-By: Jemma Issroff <jemmaissroff@gmail.com>
Right now the attached object is stored as an instance variable
and all the call sites that either get or set it have to know how it's
stored.
It's preferable to hide this implementation detail behind accessors
so that it is easier to change how it's stored.
When an object becomes "too complex" (in other words it has too many
variations in the shape tree), we transition it to use a "too complex"
shape and use a hash for storing instance variables.
Without this patch, there were rare cases where shape tree growth could
"explode" and cause performance degradation on what would otherwise have
been cached fast paths.
This patch puts a limit on shape tree growth, and gracefully degrades in
the rare case where there could be a factorial growth in the shape tree.
For example:
```ruby
class NG; end
HUGE_NUMBER.times do
NG.new.instance_variable_set(:"@unique_ivar_#{_1}", 1)
end
```
We consider objects to be "too complex" when the object's class has more
than SHAPE_MAX_VARIATIONS (currently 8) leaf nodes in the shape tree and
the object introduces a new variation (a new leaf node) associated with
that class.
For example, new variations on instances of the following class would be
considered "too complex" because those instances create more than 8
leaves in the shape tree:
```ruby
class Foo; end
9.times { Foo.new.instance_variable_set(":@uniq_#{_1}", 1) }
```
However, the following class is *not* too complex because it only has
one leaf in the shape tree:
```ruby
class Foo
def initialize
@a = @b = @c = @d = @e = @f = @g = @h = @i = nil
end
end
9.times { Foo.new }
``
This case is rare, so we don't expect this change to impact performance
of most applications, but it needs to be handled.
Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org>
obj_ivar_set and vm_setivar_slowpath is essentially doing the same thing,
but the code is duplicated and not quite implemented in the same way,
which could cause bugs. This commit refactors vm_setivar_slowpath to use
obj_ivar_set.
We would like to differentiate types of objects via their shape. This
commit adds a special T_OBJECT shape when we allocate an instance of
T_OBJECT. This allows us to avoid testing whether an object is an
instance of a T_OBJECT or not, we can just check the shape.
Alan Wu
Satoshi Tagomori
eileencodes
Takashi Kokubun
Earlopain
Étienne Barrié
Peter Zhu
Jean Boussier
Nobuyoshi Nakada
Yusuke Endoh
Aaron Patterson
Burdette Lamar
Samuel Williams
John Bampton
Jemma Issroff
Matt Valentine-House
S-H-GAMELINKS