Register Allocation for Compressed ISAs in LLVM

On Improvements of Low-Deterministic Security (2016)

Firm - Optimization and Machine Code Generation

libFirm - optimization and machine code generation

An Alternative to LLVM: libFirm [x-post /r/programming]

Firm: a C library with graph-based IR suitable for compilers

Firm is a C-library that provides a graph-based intermediate representation, optimizations, and assembly code generation suitable for use in compilers