For receiver with a singleton class, there are multiple vectors YJIT can
end up retaining the object. There is a path in jit_guard_known_klass()
that bakes the receiver into the code, and the object could also be kept
alive indirectly through a path starting at the CME object baked into
the code.
To avoid these leaks, avoid compiling calls on objects with a singleton
class.
See: https://github.com/Shopify/ruby/issues/552
[Bug #20209]
YJIT didn't guard for ruby2_keywords hash in case of splat calls that
land in methods with a rest parameter, creating incorrect results.
The compile-time checks didn't correspond to any actual effects of
ruby2_keywords, so it was masking this bug and YJIT was needlessly
refusing to compile some code. About 16% of fallback reasons in
`lobsters` was due to the ISeq check.
We already handle the tagging part with
exit_if_supplying_kw_and_has_no_kw() and should now have a dynamic guard
for all splat cases.
Note for backporting: You also need 7f51959ff1.
[Bug #20195]
```
warning: unused import: `condition::Condition`
--> src/asm/arm64/arg/mod.rs:13:9
|
13 | pub use condition::Condition;
| ^^^^^^^^^^^^^^^^^^^^
|
= note: `#[warn(unused_imports)]` on by default
warning: unused import: `rb_yjit_fix_mul_fix as rb_fix_mul_fix`
--> src/cruby.rs:188:9
|
188 | pub use rb_yjit_fix_mul_fix as rb_fix_mul_fix;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
warning: unused import: `rb_insn_len as raw_insn_len`
--> src/cruby.rs:142:9
|
142 | pub use rb_insn_len as raw_insn_len;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: `#[warn(unused_imports)]` on by default
```
Make asm public so it stops warning about unused public stuff in there.
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.
Previously, the version-controlled `cruby_bindings.inc.rs` file
contained the build-time artifact `id.h`, which nobu mentioned hinders
the goal of having fewer magic numbers in the repository.
Lookup the IDs YJIT needs on boot. It costs cycles, but it's fine since
YJIT only uses a handful of IDs at the moment. No perceptible
degradation to boot time found in my testing.
Previously, TestStack#test_machine_stack_size failed pretty consistently
on ARM64 macOS, with Rust code and part of the interpreter used for
per-instruction fallback (rb_vm_invokeblock() and friends) touching the
stack guard page and crashing with SEGV. I've also seen the same test
fail on x64 Linux, though with a different symptom.
`IO#reopen` is very special in that it is able to change the class and
singleton class of IO instances. In its presence, it is not correct to
assume that IO instances has a stable class/singleton class and guard
by comparing identity.
Remove !USE_RVARGC code
[Feature #19579]
The Variable Width Allocation feature was turned on by default in Ruby
3.2. Since then, we haven't received bug reports or backports to the
non-Variable Width Allocation code paths, so we assume that nobody is
using it. We also don't plan on maintaining the non-Variable Width
Allocation code, so we are going to remove it.
This works much like the existing `defined` implementation,
but calls out to rb_ivar_defined instead of the more general
rb_vm_defined.
Other difference to the existing `defined` implementation is
that this new instruction has to take the same operands as
the CRuby `defined_ivar` instruction.
If you have a method that takes rest arguments and a splat call that
happens to line up perfectly with that rest, you can just dupe the
array rather than move anything around. We still have to dupe, because
people could have a custom to_a method or something like that which
means it is hard to guarantee we have exclusive access to that array.
Example:
```ruby
def foo(a, b, *rest)
end
foo(1, 2, *[3, 4])
```
Given that signleton classes don't have an allocator,
we can re-use these bytes to store the attached object
in `rb_classext_struct` without making it larger.
YJIT: Implement splat for cfuncs. Split exit cases
This also implements a new check for ruby2keywords as the last
argument of a splat. This does mean that we generate more code, but in
actual benchmarks where we gained speed from this (binarytrees) I
don't see any significant slow down. I did have to struggle here with
the register allocator to find code that didn't allocate too many
registers. It's a bit hard when everything is implicit. But I think I
got to the minimal amount of copying and stuff given our current
allocation strategy.
* YJIT: Make iseq_get_location consistent with iseq.c
* YJIT: Call it "YJIT entry point"
Co-authored-by: Maxime Chevalier-Boisvert <maximechevalierb@gmail.com>
Co-authored-by: Maxime Chevalier-Boisvert <maximechevalierb@gmail.com>
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>
The new version has an option to merge everything into a big
`extern "C"` block and it's nicer.
More importantly, this upgrade fixes an issue where Ubuntu with Clang 12
and macOS with Clang 14 gave a one line diff for `rb_shape_t`. It was
slightly annoying because we use macOS locally.
Takashi Kokubun
Alan Wu
dependabot[bot]
Jean Boussier
Maxime Chevalier-Boisvert
Hiroshi SHIBATA
Peter Zhu
Jimmy Miller
Ole Friis Østergaard
Matt Valentine-House
Jemma Issroff
Aaron Patterson