porting tinycc

[fontamsoc]

I am looking to port tinycc to the PU32 instruction set described at:
https://github.com/fontamsoc/docs/blob/master/isa.md
https://github.com/fontamsoc/docs/blob/master/isa-sys.md

PU32 uses following ABI:
https://github.com/fontamsoc/docs/blob/master/abi.md

How to describe the ABI when porting tinycc ?