Millfork: a middle-level programming language targeting 6502- and Z80-based microcomputers and home consoles
This project is maintained by KarolS
Millfork was designed to be a language for developers for old 8-bit platforms, mostly game developers, who have little use for advanced features of C, but don’t have time to write assembly.
The main inspirations was Atalan, but also Quetzalcoatl, Batari BASIC and NESHLA. Sadly, Atalan has been abandoned, and the compiler has been left in a non-working state. The goal of Millfork is to succeed where Atalan failed.
Large programs in Millfork have been developed for Commodore 64.
Millfork was also tested (via emulators) to run trivial programs on other 8-bit Commodore computers, Atari 8-bit computers, Apple II, BBC Micro, ZX Spectrum 48k, NEC PC-88, MSX, CP/M, NES, Game Boy, Atari Lynx, Atari 2600 and MS-DOS.
Support for other devices using supported processors can be easily added, usually without modifying the compiler.
MOS 6502 and its descendants: 6510, 65C02, Ricoh 2A03, and to a lesser degree CSG 65CE02, Hudson Soft HuC6280 and WDC 65816. 6509 is not supported and will not be, however with some care you can treat it like a normal 6502.
Intel 8080, Intel 8085, Zilog Z80, Sharp LR35902 (also known as GBZ80)
There is also partial experimental support for Intel 8086, via automatic 8080-to-8086 translation. The generated code is very large and very slow.
Support for Motorola 6809 is coming in the future. You can test the work in progress by creating a custom platform using the 6809 CPU, but vast majority of Millfork programs will not even compile.
Assembly will not be portable. If you want to target both 6502 and Z80, you’d have to maintain two separate codebases.
Millfork is more productive. The programmer doesn’t have to worry about register allocation or variable sizes.
Millfork is usually a bit faster.
No runtime, so it’s easier to create small programs.
Many features usually found in advanced assemblers but rarely found in high-level languages are also available in Millfork, like hygienic macros, binary file inclusion, explicit memory layout, formulaic array initialization.
Millfork handles text encodings more carefully.
A wide variety of integer types of almost arbitrary sizes.
Semantics designed to suit 8-bit microprocessors, so usually less explicit casting is required.
Low-level things like the carry after arithmetic operations or single bytes of larger variables.
Built-in decimal arithmetic support.
Easy interfacing with assembly.
Unfortunately not:
Millfork is very picky. It avoids compiling complex expressions, especially those involving larger variables.
Integer math support is not very complete.
Floating point math support is absent.
Pointer arithmetic is very limited.
Millfork preprocessor is less powerful than C preprocessor.
There is no support for linking with external libraries not written in Millfork.
You either need to rewrite foreign assembly into Millfork assembly syntax,
or generate a static binary and link it manually using the file directive.
Since the compiler is a work-in-progress, some of the mentioned issues might be improved upon in the future.
See the differences from C and the differences from assembly.
It stands for MIddle Level Language FOR Kommodore computers.
(There’s also a mining town in Utah called Mill Fork, which, as fitting a compiler for obsolete machines, is currently abandoned.)
Shh.