C function frames don't need to use the VM-specific pc field to run
properly. When pushing a control frame from output code, save one
instruction by leaving the field uninitialized.
Fix-up rb_vm_svar_lep(), which is used while setting local variables via
Regexp#=~. Use cfp->iseq as a secondary signal so it can stop assuming
that all CFUNC frames always have zero pc's.
* YJIT: Add --yjit-pause and RubyVM::YJIT.resume
This allows booting YJIT in a suspended state. We chose to add a new
command line option as opposed to simply allowing YJIT.resume to work
without any command line option because it allows for combining with
YJIT tuning command line options. It also simpifies implementation.
Paired with Kokubun and Maxime.
* Update yjit.rb
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
---------
Co-authored-by: Alan Wu <XrXr@users.noreply.github.com>
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
We can only allocate enough shapes to fit in the shape buffer.
MAX_SHAPE_ID was based on the theoretical maximum number of shapes we
could have, not on the amount of memory we can actually consume. This
commit changes the MAX_SHAPE_ID to be based on the amount of memory
we're allowed to consume.
Co-Authored-By: Jemma Issroff <jemmaissroff@gmail.com>
* Revert "Remove special handling of `SIGCHLD`. (#7482)"
This reverts commit 44a0711eab.
* Revert "Remove prototypes for functions that are no longer used. (#7497)"
This reverts commit 4dce12bead.
* Revert "Remove SIGCHLD `waidpid`. (#7476)"
This reverts commit 1658e7d966.
* Fix change to rjit variable name.
We used to require MJIT is supported when YJIT is supported. However,
now that RJIT dropped some platforms that YJIT supports, it no longer
makes sense. We should be able to enable only YJIT, and vice versa.
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.
This patch is follo-up of 0a82bfe.
Without this patch, if env is escaped (Proc'ed), strange svar
can be touched.
This patch tracks escaped env and use it.
* use correct svar
Without this patch, svar location is used "nearest Ruby frame".
It is almost correct but it doesn't correct when the `each` method
is written in Ruby.
```ruby
class C
include Enumerable
def each
%w(bar baz).each{|e| yield e}
end
end
C.new.grep(/(b.)/){|e| p [$1, e]}
```
This patch fix this issue by traversing ifunc's cfp.
Note that if cfp doesn't specify this Thread's cfp stack, reserved
svar location (`ec->root_svar`) is used.
* make yjit-bindgen
---------
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
Applying the following patch to test/erb/test_erb.rb and running that
file will cause Ruby to crash on my machine (macOS 13.1 on M1 Pro):
```
--- a/test/erb/test_erb.rb
+++ b/test/erb/test_erb.rb
@@ -7,6 +7,12 @@
class TestERB < Test::Unit::TestCase
class MyError < RuntimeError ; end
+ def setup
+ GC.auto_compact = true
+ GC.stress = true
+ GC.verify_compaction_references(expand_heap: true, toward: :empty)
+ end
+
```
It crashes with the following log:
```
/Users/peter/src/ruby/lib/erb/compiler.rb:276: [BUG] Segmentation fault at 0x00000001083a8690
...
-- C level backtrace information -------------------------------------------
...
/Users/peter/src/ruby/build/ruby(rb_vm_each_stack_value+0xa8) [0x104cc3a44] ../vm.c:2737
/Users/peter/src/ruby/build/ruby(rb_vm_each_stack_value+0xa8) [0x104cc3a44] ../vm.c:2737
/Users/peter/src/ruby/build/ruby(check_stack_for_moved+0x2c) [0x104b272a4] ../gc.c:5512
/Users/peter/src/ruby/build/ruby(gc_compact_finish) ../gc.c:5534
/Users/peter/src/ruby/build/ruby(gc_sweep_compact) ../gc.c:8653
/Users/peter/src/ruby/build/ruby(gc_sweep) ../gc.c:6196
/Users/peter/src/ruby/build/ruby(has_sweeping_pages+0x0) [0x104b19c54] ../gc.c:9568
/Users/peter/src/ruby/build/ruby(gc_rest) ../gc.c:9570
```
This crash happens because it's reading the VALUE at sp. But since
sp points to the top of the stack, it's reading the VALUE above the
top of the stack, which is causing this segfault.
Fixes [Bug #19320]
I noticed this while running test_yjit with --mjit-call-threshold=1,
which redefines `Integer#<`. When Ruby is monkey-patched,
MJIT itself could be broken.
Similarly, Ruby scripts could break MJIT in many different ways. I
prepared the same set of hooks as YJIT so that we could possibly
override it and disable it on those moments. Every constant under
RubyVM::MJIT is private and thus it's an unsupported behavior though.
On a hash miss we need to call default if it is redefined in order to
return the default value to be used. Previously we checked this with
rb_method_basic_definition_p, which avoids the method call but requires
a method lookup.
This commit replaces the previous check with BASIC_OP_UNREDEFINED_P and
a new BOP_DEFAULT. We still need to fall back to
rb_method_basic_definition_p when called on a subclasss of hash.
| |compare-ruby|built-ruby|
|:---------------|-----------:|---------:|
|hash_aref_miss | 2.692| 3.531|
| | -| 1.31x|
Co-authored-by: Daniel Colson <danieljamescolson@gmail.com>
Co-authored-by: "Ian C. Anderson" <ian@iancanderson.com>
Co-authored-by: Jack McCracken <me@jackmc.xyz>
All values should have a MJIT_ prefix. We could address the warning for
the end mark if we just define the macro for the check next to the enum.
It even simplifies some code for checking the enum.
Prior to this commit the `OPTIMIZED_CMP` macro relied on a method lookup
to determine whether `<=>` was overridden. The result of the lookup was
cached, but only for the duration of the specific method that
initialized the cmp_opt_data cache structure.
With this method lookup, `[x,y].max` is slower than doing `x > y ?
x : y` even though there's an optimized instruction for "new array max".
(John noticed somebody a proposed micro-optimization based on this fact
in https://github.com/mastodon/mastodon/pull/19903.)
```rb
a, b = 1, 2
Benchmark.ips do |bm|
bm.report('conditional') { a > b ? a : b }
bm.report('method') { [a, b].max }
bm.compare!
end
```
Before:
```
Comparison:
conditional: 22603733.2 i/s
method: 19820412.7 i/s - 1.14x (± 0.00) slower
```
This commit replaces the method lookup with a new CMP basic op, which
gives the examples above equivalent performance.
After:
```
Comparison:
method: 24022466.5 i/s
conditional: 23851094.2 i/s - same-ish: difference falls within
error
```
Relevant benchmarks show an improvement to Array#max and Array#min when
not using the optimized newarray_max instruction as well. They are
noticeably faster for small arrays with the relevant types, and the same
or maybe a touch faster on larger arrays.
```
$ make benchmark COMPARE_RUBY=<master@5958c305> ITEM=array_min
$ make benchmark COMPARE_RUBY=<master@5958c305> ITEM=array_max
```
The benchmarks added in this commit also look generally improved.
Co-authored-by: John Hawthorn <jhawthorn@github.com>
This commit moves ruby_basic_operators and the unredefined macros out of
vm_core.h and into basic_operators.h so that we can use them more
broadly in places where we currently use a method look up via
`rb_method_basic_definition_p` (e.g. object.c, numeric.c, complex.c,
enum.c, but also in internal/compar.h after introducing BOP_CMP and
elsewhere if we introduce more BOPs)
The most controversial part of this change is probably moving
redefined_flag out of rb_vm_t. [vm_opt_method_def_table and
vm_opt_mid_table](9da2a5204f/vm.c)
are not part of rb_vm_t either, and I think this fits well with those.
But more significantly it seems to result in one fewer instruction. For
example:
Before:
```
(lldb) disassemble -n vm_opt_str_freeze
miniruby`vm_exec_core:
miniruby[0x10028233e] <+14558>: movq 0x11a86b(%rip), %rax ; ruby_current_vm_ptr
miniruby[0x100282345] <+14565>: testb $0x4, 0x242c(%rax)
```
After:
```
(lldb) disassemble -n vm_opt_str_freeze
ruby`vm_exec_core:
ruby[0x100280ebe] <+14510>: testb $0x4, 0x120147(%rip) ; ruby_vm_redefined_flag + 43
```
Co-authored-by: John Hawthorn <jhawthorn@github.com>
Previously, for statically-linked extensions, we used
`vm->loading_table` to delay calling the init function until the
extensions are required. This caused the extensions to look like they
are in the middle of being loaded even before they're required.
(`rb_feature_p()` returned true with a loading path output.) Combined
with autoload, queries like `defined?(CONST)` and `Module#autoload?`
were confused by this and returned nil incorrectly. RubyGems uses
`defined?` to detect if OpenSSL is available and failed when OpenSSL was
available in builds using `--with-static-linked-ext`.
Use a dedicated table for the init functions instead of adding them to
the loading table. This lets us remove some logic from non-EXTSTATIC
builds.
[Bug #19115]
We need to track this number in CI. It's important to know how changes
to the codebase impact the number of shapes in the system, so lets add
the number to the VM stat hash
The structure and readability of jit_exec is messed up right now. I'd
like to help the current situation by this for now. I'll resurrect
them when I need it again.
This commit adds a `capacity` field to shapes, and adds shape
transitions whenever an object's capacity changes. Objects which are
allocated out of a bigger size pool will also make a transition from the
root shape to the shape with the correct capacity for their size pool
when they are allocated.
This commit will allow us to remove numiv from objects completely, and
will also mean we can guarantee that if two objects share shapes, their
IVs are in the same positions (an embedded and extended object cannot
share shapes). This will enable us to implement ivar sets in YJIT using
object shapes.
Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org>
Before object shapes, we were using class serial to invalidate
inline caches. Now that we use shape_id for inline cache keys,
the class serial is unnecessary.
Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org>
This patch pushes dummy frames when loading code for the
profiling purpose.
The following methods push a dummy frame:
* `Kernel#require`
* `Kernel#load`
* `RubyVM::InstructionSequence.compile_file`
* `RubyVM::InstructionSequence.load_from_binary`
https://bugs.ruby-lang.org/issues/18559
Prior to this commit, we were reading and writing ivar index and
shape ID in inline caches in two separate instructions when
getting and setting ivars. This meant there was a race condition
with ractors and these caches where one ractor could change
a value in the cache while another was still reading from it.
This commit instead reads and writes shape ID and ivar index to
inline caches atomically so there is no longer a race condition.
Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org>
Co-Authored-By: John Hawthorn <john@hawthorn.email>
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 <tenderlove@ruby-lang.org>
Co-Authored-By: Eileen M. Uchitelle <eileencodes@gmail.com>
Co-Authored-By: John Hawthorn <john@hawthorn.email>
