That is hardly novel, here is the thesis for the Oberon multithreaded compiler from 2003.
https://www.research-collection.ethz.ch/entities/publication...
C# compiler is also fully multithreaded since the Roslyn rewrite in 2016.
The novelty is in parrelizing LLVM, which is traditionally a single-thread code generator.
The novelty is in parrelizing LLVM, which is traditionally a single-thread code generator.