Support 1st group of RISC-V Bitmanip backend target features #100528
Merged
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These target features use the same names as LLVM and
is_riscv_feature_detected!
, they are: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
=)