I think this master's thesis from our group could be of
interest. It describes the "bridge" between the LLVM codegen
and our custom TTA codegen in TCE: a runtime retargetable architecture
description file driven LLVM compiler backend. The thesis might be
useful also for people implementing backends for LLVM in general.
If you have any questions or comments, please direct them to
me (I'm not the author of this thesis despite my almost identical
name) as the author is no longer working for our department.
The abstract from the thesis: