Previously YARV bytecode implemented constant caching by having a pair
of instructions, opt_getinlinecache and opt_setinlinecache, wrapping a
series of getconstant calls (with putobject providing supporting
arguments).
This commit replaces that pattern with a new instruction,
opt_getconstant_path, handling both getting/setting the inline cache and
fetching the constant on a cache miss.
This is implemented by storing the full constant path as a
null-terminated array of IDs inside of the IC structure. idNULL is used
to signal an absolute constant reference.
$ ./miniruby --dump=insns -e '::Foo::Bar::Baz'
== disasm: #<ISeq:<main>@-e:1 (1,0)-(1,13)> (catch: FALSE)
0000 opt_getconstant_path <ic:0 ::Foo::Bar::Baz> ( 1)[Li]
0002 leave
The motivation for this is that we had increasingly found the need to
disassemble the instructions between the opt_getinlinecache and
opt_setinlinecache in order to determine the constant we are fetching,
or otherwise store metadata.
This disassembly was done:
* In opt_setinlinecache, to register the IC against the constant names
it is using for granular invalidation.
* In rb_iseq_free, to unregister the IC from the invalidation table.
* In YJIT to find the position of a opt_getinlinecache instruction to
invalidate it when the cache is populated
* In YJIT to register the constant names being used for invalidation.
With this change we no longe need disassemly for these (in fact
rb_iseq_each is now unused), as the list of constant names being
referenced is held in the IC. This should also make it possible to make
more optimizations in the future.
This may also reduce the size of iseqs, as previously each segment
required 32 bytes (on 64-bit platforms) for each constant segment. This
implementation only stores one ID per-segment.
There should be no significant performance change between this and the
previous implementation. Previously opt_getinlinecache was a "leaf"
instruction, but it included a jump (almost always to a separate cache
line). Now opt_getconstant_path is a non-leaf (it may
raise/autoload/call const_missing) but it does not jump. These seem to
even out.
I'm planning to introduce mjit_compiler.rb, and I want to make this
consistent with it. Consistency with compile.c doesn't seem important
for MJIT anyway.
* Optimize Marshal dump of large fixnum
Marshal's FIXNUM type only supports 31-bit fixnums, so on 64-bit
platforms the 63-bit fixnums need to be represented in Marshal's
BIGNUM.
Previously this was done by converting to a bugnum and serializing the
bignum object.
This commit avoids allocating the intermediate bignum object, instead
outputting the T_FIXNUM directly to a Marshal bignum. This maintains the
same representation as the previous implementation, including not using
LINKs for these large fixnums (an artifact of the previous
implementation always allocating a new BIGNUM).
This commit also avoids unnecessary st_lookups on immediate values,
which we know will not be in that table.
* Fastpath for loading FIXNUM from Marshal bignum
* Run update-deps
Creates simple bin stubs to load the extracted executable files.
After only extracted under `gems` directory, the gems are considered
installed but the executable scripts are not found.
Also the second argument is now the parent of the previous second and
third arguments.
Since #6006, we no longer avoid executing GC on mjit_worker.c and thus
there's no need to carefully change how we write code whether you're in
mjit.c or mjit_worker.c anymore.
The annocheck supports ELF format binaries compiled for any OS and for any
architecture. It can work in not only Linux but also FreeBSD and Solaris.
It is designed to be independent of the host OS and the architecture.
Even in Mac, as the binaries are Mach-O foramt, the annocheck fails correctly
with the message.
e.g. Test binaries compiled for Mac OSX 10.13.6 (target_os: darwin17) in Fedora 35.
```
$ cat /etc/fedora-release
Fedora release 35 (Thirty Five)
$ file ruby
ruby: Mach-O 64-bit x86_64 executable, flags:<NOUNDEFS|DYLDLINK|TWOLEVEL|WEAK_DEFINES|BINDS_TO_WEAK|PIE>
$ annocheck ruby
annocheck: Version 10.66.
annocheck: Warning: ruby: is not an ELF format file.
```
See <https://sourceware.org/bugzilla/show_bug.cgi?id=29173> for details.
In December 2021, we opened an [issue] to solicit feedback regarding the
porting of the YJIT codebase from C99 to Rust. There were some
reservations, but this project was given the go ahead by Ruby core
developers and Matz. Since then, we have successfully completed the port
of YJIT to Rust.
The new Rust version of YJIT has reached parity with the C version, in
that it passes all the CRuby tests, is able to run all of the YJIT
benchmarks, and performs similarly to the C version (because it works
the same way and largely generates the same machine code). We've even
incorporated some design improvements, such as a more fine-grained
constant invalidation mechanism which we expect will make a big
difference in Ruby on Rails applications.
Because we want to be careful, YJIT is guarded behind a configure
option:
```shell
./configure --enable-yjit # Build YJIT in release mode
./configure --enable-yjit=dev # Build YJIT in dev/debug mode
```
By default, YJIT does not get compiled and cargo/rustc is not required.
If YJIT is built in dev mode, then `cargo` is used to fetch development
dependencies, but when building in release, `cargo` is not required,
only `rustc`. At the moment YJIT requires Rust 1.60.0 or newer.
The YJIT command-line options remain mostly unchanged, and more details
about the build process are documented in `doc/yjit/yjit.md`.
The CI tests have been updated and do not take any more resources than
before.
The development history of the Rust port is available at the following
commit for interested parties:
1fd9573d8b
Our hope is that Rust YJIT will be compiled and included as a part of
system packages and compiled binaries of the Ruby 3.2 release. We do not
anticipate any major problems as Rust is well supported on every
platform which YJIT supports, but to make sure that this process works
smoothly, we would like to reach out to those who take care of building
systems packages before the 3.2 release is shipped and resolve any
issues that may come up.
[issue]: https://bugs.ruby-lang.org/issues/18481
Co-authored-by: Maxime Chevalier-Boisvert <maximechevalierb@gmail.com>
Co-authored-by: Noah Gibbs <the.codefolio.guy@gmail.com>
Co-authored-by: Kevin Newton <kddnewton@gmail.com>
Nobuyoshi Nakada
Takashi Kokubun
John Hawthorn
Hiroshi SHIBATA
Jean Boussier
Peter Zhu
Jemma Issroff
Kevin Backhouse
Jun Aruga
Alan Wu