75da570d78
Use the object crate for metadata reading This allows sharing the metadata reader between cg_llvm, cg_clif and other codegen backends. This is not currently useful for rlib reading with cg_spirv ([rust-gpu](https://github.com/EmbarkStudios/rust-gpu/)) as it uses tar rather than ar as .rlib format, but it is useful for dylib reading required for loading proc macros. (cc `@eddyb)` The object crate is already trusted as dependency of libstd through backtrace. As far as I know it supports reading all object file formats used by targets for which we support rust dylibs with crate metadata, but I am not certain. If this happens to not be the case, I could keep using LLVM for reading dylib metadata. Marked as WIP for a perf run and as it is based on #83637. |
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| .. | ||
| .github/workflows | ||
| .vscode | ||
| build_sysroot | ||
| crate_patches | ||
| docs | ||
| example | ||
| patches | ||
| scripts | ||
| src | ||
| .cirrus.yml | ||
| .gitattributes | ||
| .gitignore | ||
| build.sh | ||
| Cargo.lock | ||
| Cargo.toml | ||
| clean_all.sh | ||
| LICENSE-APACHE | ||
| LICENSE-MIT | ||
| prepare.sh | ||
| Readme.md | ||
| rust-toolchain | ||
| rustfmt.toml | ||
| test.sh | ||
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.
Building and testing
$ git clone https://github.com/bjorn3/rustc_codegen_cranelift.git
$ cd rustc_codegen_cranelift
$ ./prepare.sh # download and patch sysroot src and install hyperfine for benchmarking
$ ./build.sh
To run the test suite replace the last command with:
$ ./test.sh
This will implicitly build cg_clif too. Both build.sh and test.sh accept a --debug argument to
build in debug mode.
Alternatively you can download a pre built version from GHA. It is listed in the artifacts section of workflow runs. Unfortunately due to GHA restrictions you need to be logged in to access it.
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 (prepare.sh and build.sh or test.sh).
In the directory with your project (where you can do the usual cargo build), run:
$ $cg_clif_dir/build/cargo.sh 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.
Configuration
See the documentation on the BackendConfig struct in config.rs for all
configuration options.
Not yet supported
- Inline assembly (no cranelift support)
- On Linux there is support for invoking an external assembler for
global_asm!andasm!.llvm_asm!will remain unimplemented forever.asm!doesn't yet support reg classes. You have to specify specific registers instead.
- On Linux there is support for invoking an external assembler for
- SIMD (tracked here, some basic things work)
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.