This quote from your reference gives the answer: We also considered using dynasm, but found the tooling that comes with asmjit to be better. EDIT: But it still

This quote from your reference gives the answer: We also considered using dynasm, but found the tooling that comes with asmjit to be better. EDIT: But it still gives no answer why they preferred asmjit in favour of other solutions than LLVM or DynASM (where the latter is just an assembler which helps to integrate with C code, not a platform abstraction like LLVM or others).