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>
Add a hook point to initialize extra extension libraries. The default
hook function is replaced when linking a strong `Init_extra_exts`
symbol. A builder can insert an object file that defines Init_extra_exts
by XLDFLAGS.
```
compiling ../ruby.c
../ruby.c:1547:17: error: implicit declaration of function 'setup_yjit_options' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
setup_yjit_options(s, &opt->yjit);
^
../ruby.c:1547:17: note: did you mean 'setup_mjit_options'?
../ruby.c:1122:1: note: 'setup_mjit_options' declared here
setup_mjit_options(const char *s, struct mjit_options *mjit_opt)
^
../ruby.c:1547:45: error: no member named 'yjit' in 'struct ruby_cmdline_options'; did you mean 'mjit'?
setup_yjit_options(s, &opt->yjit);
^~~~
mjit
../ruby.c:192:25: note: 'mjit' declared here
struct mjit_options mjit;
^
../ruby.c:1924:28: error: no member named 'yjit' in 'struct ruby_cmdline_options'; did you mean 'mjit'?
rb_yjit_init(&opt->yjit);
^~~~
mjit
../ruby.c:192:25: note: 'mjit' declared here
struct mjit_options mjit;
^
3 errors generated.
```
* Rename --jit to --mjit
[Feature #18349]
* Fix a few more --jit references
* Fix MJIT Actions
* More s/jit/mjit/ and re-introduce --disable-jit
* Update NEWS.md
* Fix test_bug_reporter_add
* Add --yjit-no-type-prop so we can test YJIT without type propagation
* Fix typo in command line option
* Leave just two test workflows enable for YJIT
TestRubyOptions#test_enable was broken on OpenBSD after the yjit
merge. --yjit (and --enable-all, which enables --yjit) fails on
OpenBSD because yjit uses an insecure mmap call (both writable
and executable), in alloc_exec_mem, which OpenBSD does not allow.
This can probably be reverted if yjit switches to a more secure
mmap design (writable xor executable). This would involve
initially calling mmap with PROT_READ | PROT_WRITE, and after writing
of executable code has finished, using mprotect to switch to
PROT_READ | PROT_EXEC. I believe Firefox uses this approach for
their Javascript engine since Firefox 46.
Previously, options such as "--yjit123" would enable YJIT. Additionally,
the error message for argument parsing mentioned "--jit-..." instead of
"--yjit-...".