17914c89ec
Support 1st group of RISC-V Bitmanip backend target features These target features use the same names as LLVM and `is_riscv_feature_detected!`, they are: - zba (address generation instructions) - zbb (basic bit manipulation) - zbc (carry-less multiplication) - zbs (single-bit manipulation) The extension is frozen and ratified, and I don't think we should expect LLVM to change those feature names in the future. For reference, the specification for the B extension can be found here: https://github.com/riscv/riscv-bitmanip/releases/download/1.0.0/bitmanip-1.0.0-38-g865e7a7.pdf) On my current project, I see a 7.6% reduction in binary size with these features on, so I have some incentive to try to silence the "unknown feature" warning from `-Ctarget-feature` =) |
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| Cargo.toml | ||
| README.md | ||
Please read the rustc-dev-guide chapter on Backend Agnostic Codegen.