Work in progress cranelift codegen backend for rust

⚠⚠⚠ This doesn't do anything useful yet ⚠⚠⚠

Building

$ git clone https://github.com/bjorn3/rustc_codegen_cranelift.git
$ cd rustc_codegen_cranelift
$ git submodule update --init
$ cargo build

Usage

$ rustc -Zcodegen-backend=$(pwd)/target/debug/librustc_codegen_cranelift.so my_crate.rs --crate-type lib -Og

You must compile with -Og, because checked binops are not yet supported.

Building libcore

$ git clone https://github.com/rust-lang/rust.git
$ cd rust
$ git apply ../0001-Disable-stdsimd-in-libcore.patch
$ git apply ../0002-Disable-u128-and-i128-in-libcore.patch
$ cd ../
$ ./build.sh

⚠⚠⚠ You will get a panic because of unimplemented stuff ⚠⚠⚠

Not yet supported

• Checked binops

• Statics

• Drop glue

• Building libraries

• Other call abi's

• Unsized types

• Slice indexing

• Sub slice

• Closures

• Some rvalue's

• Inline assembly

• Custom sections

Known errors

• cranelift-module api seems to be used wrong, thus causing panic for some consts
• cranelift-codegen doesn't have encodings for some instructions for types smaller than I32
• thread 'main' panicked at 'assertion failed: !value.has_escaping_regions()', librustc/ty/sty.rs:754:9 in cton_sig_from_mono_fn_sig