5ce3797073
MIR dumping is a mess. There are lots of functions and entry points, e.g. `dump_mir`, `dump_mir_with_options`, `dump_polonius_mir`, `dump_mir_to_writer`. Also, it's crucial that `create_dump_file` is never called without `dump_enabled` first being checked, but there is no mechanism for ensuring this and it's hard to tell if it is satisfied on all paths. (`dump_enabled` is checked twice on some paths, however!) This commit introduces `MirWriter`, which controls the MIR writing, and encapsulates the `extra_data` closure and `options`. Two existing functions are now methods of this type. It sets reasonable defaults, allowing the removal of many `|_, _| Ok(())` closures. The commit also introduces `MirDumper`, which is layered on top of `MirWriter`, and which manages the creation of the dump files, encapsulating pass names, disambiguators, etc. Four existing functions are now methods of this type. - `MirDumper::new` will only succeed if dumps are enabled, and will return `None` otherwise, which makes it impossible to dump when you shouldn't. - It also sets reasonable defaults for various things like disambiguators, which means you no longer need to specify them in many cases. When they do need to be specified, it's now done via setter methods. - It avoids some repetition. E.g. `dump_nll_mir` previously specifed the pass name `"nll"` four times and the disambiguator `&0` three times; now it specifies them just once, to put them in the `MirDumper`. - For Polonius, the `extra_data` closure can now be specified earlier, which avoids having to pass some arguments through some functions.
Cranelift codegen backend for rust
The goal of this project is to create an alternative codegen backend for the rust compiler based on Cranelift. This has the potential to improve compilation times in debug mode. If your project doesn't use any of the things listed under "Not yet supported", it should work fine. If not please open an issue.
Download using Rustup
The Cranelift codegen backend is distributed in nightly builds on Linux, macOS and x86_64 Windows. If you want to install it using Rustup, you can do that by running:
$ rustup component add rustc-codegen-cranelift-preview --toolchain nightly
Once it is installed, you can enable it with one of the following approaches:
CARGO_PROFILE_DEV_CODEGEN_BACKEND=cranelift cargo +nightly build -Zcodegen-backend- Add the following to
.cargo/config.toml:[unstable] codegen-backend = true [profile.dev] codegen-backend = "cranelift" - Add the following to
Cargo.toml:# This line needs to come before anything else in Cargo.toml cargo-features = ["codegen-backend"] [profile.dev] codegen-backend = "cranelift"
Precompiled builds
You can also download a pre-built version from the releases page.
Extract the dist directory in the archive anywhere you want.
If you want to use cargo clif build instead of having to specify the full path to the cargo-clif executable, you can add the bin subdirectory of the extracted dist directory to your PATH.
(tutorial for Windows, and for Linux/MacOS).
Building and testing
If you want to build the backend manually, you can download it from GitHub and build it yourself:
$ git clone https://github.com/rust-lang/rustc_codegen_cranelift
$ cd rustc_codegen_cranelift
$ ./y.sh build
To run the test suite replace the last command with:
$ ./y.sh prepare # only needs to be run the first time
$ ./test.sh
For more docs on how to build and test see build_system/usage.txt or the help message of ./y.sh.
Platform support
| OS \ architecture | x86_64 | AArch64 | Riscv64 | s390x (System-Z) |
|---|---|---|---|---|
| Linux | ✅ | ✅ | ✅1 | ✅1 |
| FreeBSD | ✅1 | ❓ | ❓ | ❓ |
| AIX | ❌2 | N/A | N/A | ❌2 |
| Other unixes | ❓ | ❓ | ❓ | ❓ |
| macOS | ✅ | ✅ | N/A | N/A |
| Windows | ✅ | ❌ | N/A | N/A |
✅: Fully supported and tested ❓: Maybe supported, not tested ❌: Not supported at all
Not all targets are available as rustup component for nightly. See notes in the platform support matrix.
Usage
rustc_codegen_cranelift can be used as a near-drop-in replacement for cargo build or cargo run for existing projects.
Assuming $cg_clif_dir is the directory you cloned this repo into and you followed the instructions (y.sh prepare and y.sh build or test.sh).
In the directory with your project (where you can do the usual cargo build), run:
$ $cg_clif_dir/dist/cargo-clif build
This will build your project with rustc_codegen_cranelift instead of the usual LLVM backend.
For additional ways to use rustc_codegen_cranelift like the JIT mode see usage.md.
Building and testing with changes in rustc code
See rustc_testing.md.
Not yet supported
- SIMD (tracked here,
std::simdfully works,std::archis partially supported) - Unwinding on panics (no cranelift support,
-Cpanic=abortis enabled by default)
License
Licensed under either of
- Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
at your option.
Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you shall be dual licensed as above, without any additional terms or conditions.
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Not available as rustup component for nightly. You can build it yourself. ↩︎
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XCOFF object file format is not supported. ↩︎