ruby.git/internal/object.h, branch v4.0.2

Remove unused RBASIC_RESET_FLAGS

2025-06-02T13:52:25+00:00

Add shape_id to RBasic under 32 bit

2025-05-26T08:31:54+00:00

This makes `RBobject` `4B` larger on 32 bit systems
but simplifies the implementation a lot.

[Feature #21353]

Co-authored-by: Jean Boussier

Rename `ivptr` -> `fields`, `next_iv_index` -> `next_field_index`

2025-05-08T05:58:05+00:00

Ivars will longer be the only thing stored inline
via shapes, so keeping the `iv_index` and `ivptr` names
would be confusing.

Instance variables won't be the only thing stored inline
via shapes, so keeping the `ivptr` name would be confusing.

`field` encompass anything that can be stored in a VALUE array.

Similarly, `gen_ivtbl` becomes `gen_fields_tbl`.

Move rb_class_allocate_instance from gc.c to object.c

2024-02-14T18:43:02+00:00

proc.c: get rid of `CLONESETUP`

2024-02-12T17:31:48+00:00

[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

Re-embed when removing Object instance variables

2023-12-06T16:34:07+00:00

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.

Stop exporting symbols for MJIT

2023-03-07T05:59:23+00:00

Revert "Revert "This commit implements the Object Shapes technique in CRuby.""

2022-10-11T15:40:56+00:00

This reverts commit 9a6803c90b817f70389cae10d60b50ad752da48f.

Revert "This commit implements the Object Shapes technique in CRuby."

2022-09-30T23:01:50+00:00

This reverts commit 68bc9e2e97d12f80df0d113e284864e225f771c2.

This commit implements the Object Shapes technique in CRuby.

2022-09-28T15:26:21+00:00

Object Shapes is used for accessing instance variables and representing the
"frozenness" of objects.  Object instances have a "shape" and the shape
represents some attributes of the object (currently which instance variables are
set and the "frozenness").  Shapes form a tree data structure, and when a new
instance variable is set on an object, that object "transitions" to a new shape
in the shape tree.  Each shape has an ID that is used for caching. The shape
structure is independent of class, so objects of different types can have the
same shape.

For example:

```ruby
class Foo
  def initialize
    # Starts with shape id 0
    @a = 1 # transitions to shape id 1
    @b = 1 # transitions to shape id 2
  end
end

class Bar
  def initialize
    # Starts with shape id 0
    @a = 1 # transitions to shape id 1
    @b = 1 # transitions to shape id 2
  end
end

foo = Foo.new # `foo` has shape id 2
bar = Bar.new # `bar` has shape id 2
```

Both `foo` and `bar` instances have the same shape because they both set
instance variables of the same name in the same order.

This technique can help to improve inline cache hits as well as generate more
efficient machine code in JIT compilers.

This commit also adds some methods for debugging shapes on objects.  See
`RubyVM::Shape` for more details.

For more context on Object Shapes, see [Feature: #18776]

Co-Authored-By: Aaron Patterson 
Co-Authored-By: Eileen M. Uchitelle 
Co-Authored-By: John Hawthorn