The 6502 is notoriously difficult to write a compiler for because it has only three general-purpose registers and it doesn’t have a stack-relative addressing mode, meaning there’s not really an efficient way to implement local variables.

When writing 6502 assembly by hand, you usually just create a few global variables as “temporaries” for storage, parameter passing, etc. and you write your code carefully to make sure any subroutines you call don’t try to use a temporary you’re already using, or anything like that. Obviously, this doesn’t look anything like idiomatic C.

For this reason, I’m really interested in seeing what kind of code this generates and how it performs, especially compared to the dominant 6502 compiler cc65 (https://cc65.github.io/).