Create MOS Technology 6502 backend

[ikskuh]

The MOS Technology 6502 is one of the most famous processors which was used in a lot of home computers in the 80ies.
Even today it is mostly programmed in assembly. There aren't many compilers available, most prominent one is cc65, a C compiler.

Zig would be in a unique position to be a modern compiler for the 6502 processor family.

The 6502 does not have a huge instruction set, but has a lot of restrictions which makes code generation and optimization hard, but i think it's still worth a try.

Imagine programming your C64 in Zig!

[mlarouche]

My name is Michaël Larouche and I fully support this effort

[notCalle]

May I pretty please have support for the 65c816 (the super-weird 16 bit version) too?

No, I refuse to wait for #65816 to propose it

[Xe]

This repo may be useful there: https://github.com/c64scene-ar/llvm-6502

[ikskuh]

@notCalle i think the next up would be #6800 and #68000, even though that is a bit far away

[notCalle]

Too bad #80 is already gone, because Z80.

[nektro]

Also want to point out that the Nintendo Entertainment System (NES)(1983) ran on a modified 6502 so support for this arch could enable the writing of NES ROMs in Zig

cpu: https://wiki.nesdev.com/w/index.php/CPU
rom format: https://wiki.nesdev.com/w/index.php/INES