llvm-bleach is a tool for lifting LLVM MIR files to LLVM IR. The main feature of bleach is that it has no backends inside the tool itself. It only uses platform-independent LLVM MC library information and input configuration files (that can be modified by user). Currently bleach ships with configuration files for a subset of RISC-V instructions (rv32/64 with M extension). To add any other architecture to llvm-bleach one only needs to write a configuration file describing target platform instructions. No source modification required.

You can easily build bleach with nix:

nix build .

And run:

# Generate config file (optional)
result/bin/bleach-config-gen --march rv64imdf --template-dir result/share/templates -o newconfig.yaml
# Run bleach with generated config file
result/bin/llvm-bleach path/to/program.mir --instructions=newconfig.yaml

You can fetch all the required dependencies using nix

nix develop .

cmake -S . -B build
cmake --build build

llvm-bleach currently comes with documentation for all of 3 distributed tools:

• llvm-bleach - LLVM MIR to LLVM IR lifter
• mctomir - machine code to MIR lifter
• bleach-config-gen - helper tool to generate architecture configs for llvm-bleach from available templates.

Currently llvm-bleach supports rv64/rv32 basic instruction sets for I configurations. Supported extensions include:

• M - Integer multiplication and division
• F - Single-precision floating-point operations
• D - Double-precision floating-point operations