I'd like to add PowerPC 603/604 to the list of assemblers I'm working with and write a Higgs compiler backend for it (thus bringing my entire codebase to PPC ecosystem), given I already wrote one for RISC DSP/GPU before.
While I am not going to put my engine and game work to halt because of it, that'll naturally come to an end in about 4 months once my part-time job becomes full-time (for about 6 months) again around June.

And this project is something that's doable on that kind of random schedule (unlike game coding) during July-December, as separate language commands are easily doable within half day here and there, whenever I am back home from travelling.

But I need Dev environment first, to learn the PPC ASM (ideally an interactive one, showing all registers and allowing stepping through the code).

I don't want to just try setting up first thing I google, as I have zero exposure to PPC and would thus miss implications of such decision and as there's many people who have been in this space for decades, I figured I could just ask here and get the conversation going.

So, I need:
1. PPC 603 Assembler (command-line, Windows executable)
2. Virtual Machine with whichever OS is used there
3. Ideally, if possible, this would work within WinUAE which I use for testing

I tried asking this question on RISC-V subreddit, but it got flagged as off-topic there and deleted

Heimdall Quote:

So, I need: 1. PPC 603 Assembler (command-line, Windows executable)

You mentioned you were already using Frank Wille's VASM assembler which is a cross assembler that supports PPC. The VBCC cross compiler, and VASM the assembler for it, not only support PPC but multiple Amiga targets (PPC MorphOS, PPC AmigaOS 4, PPC WarpOS and PPC PowerUP).

http://sun.hasenbraten.de/vbcc/

I do not know about a PPC simulator but "The PowerPC Compiler Writer’s Guide" is good documentation for a compiler backend and instruction scheduler that covers early PPC CPUs like the PPC 603(e) and 604(e) including optimized PPC assembly code.

The PowerPC Compiler Writer’s Guide
https://cr.yp.to/2005-590/powerpc-cwg.pdf

Do not expect help with PPC assembly, optimizations and debugging from Amiga Neverland. PPC assembly experts do not exist here or in most places as PPC assembly is more dead in use than 68k assembly at this point. Reading the VBCC and VASM docs and then e-mailing Frank Wille with remaining questions is your best bet for Amiga related PPC questions. He can program PPC assembly and has written some PPC optimizations/inlines but no games unlike his many 68k Amiga games he enjoys writing, as I linked in another thread. A-EonKit sabotage of the 68k Amiga has failed to result in games written in PPC assembly, PPC software optimizations anywhere near the the scale of x86-64 software optimizations or even PPC SMP working as well as AROS x86-64 SMP after more than a decade. Maybe it is no worse than Jaguar hardware bugs and bottlenecks though.

Last edited by matthey on 10-Feb-2025 at 06:40 PM.
Last edited by matthey on 10-Feb-2025 at 06:37 PM.

Quote:

matthey wrote: You mentioned you were already using Frank Wille's VASM assembler which is a cross assembler that supports PPC. The VBCC cross compiler, and VASM the assembler for it, not only support PPC but multiple Amiga targets (PPC MorphOS, PPC AmigaOS 4, PPC WarpOS and PPC PowerUP). http://sun.hasenbraten.de/vbcc/

Oh, wow - I am truly utterly unobservant Been using vasm for over half a decade, yet didn't notice it supports PowerPC targets ! I just checked the vasm.pdf, and - yep - there it is !!!

This is actually super important, because I won't have to write different handler for a different assembler into my compiler, as vasm support is already there, hence it'll make the very first compilation much easier!

Quote:

matthey wrote: I do not know about a PPC simulator but "The PowerPC Compiler Writer’s Guide" is good documentation for a compiler backend and instruction scheduler that covers early PPC CPUs like the PPC 603(e) and 604(e) including optimized PPC assembly code. The PowerPC Compiler Writer’s Guide https://cr.yp.to/2005-590/powerpc-cwg.pdf

That is a vey good PDF, sir !
It contains examples of the basic code flow and the many ways how to translate it into PPC ops. I wish I had it for Jaguar, for sure !

On the other hand, my experience with the first RISC compiler (for Jaguar's DSP and GPU) is still beneficial, because I can now actually design the PPC Backend in a way that will take scheduling into account from the very start.

Meaning, I'll design it so that each instruction has an added information about all of its pipeline stages, This way, the compiler, at any point, will contain the exact replica of the HW's pipeline stages and will be able to [eventually] make intelligent decisions about the best instructions to use, at that particular point.

More importantly, I already have a Cycle-Count Option for the Block, which prints out during compilation, detailed info on all cycles consumed (if the specific CPU target has that feature implemented).
This will be very useful for benchmarking of inner loops, as I can easily extend this to contain additional info on pipeline.

Quote:

matthey wrote: Do not expect help with PPC assembly, optimizations and debugging from Amiga Neverland. PPC assembly experts do not exist here or in most places as PPC assembly is more dead in use than 68k assembly at this point. Reading the VBCC and VASM docs and then e-mailing Frank Wille with remaining questions is your best bet for Amiga related PPC questions. He can program PPC assembly and has written some PPC optimizations/inlines but no games unlike his many 68k Amiga games he enjoys writing, as I linked in another thread. A-EonKit sabotage of the 68k Amiga has failed to result in games written in PPC assembly, PPC software optimizations anywhere near the the scale of x86-64 software optimizations or even PPC SMP working as well as AROS x86-64 SMP after more than a decade. Maybe it is no worse than Jaguar hardware bugs and bottlenecks though.

Well, but there's gotta be at least a dozen active PPC coders, or not even that many anymore ? They must hang out somewhere.
Frank's busy with his compiler suite, wouldn't want to bother him with newbie questions...

Maybe they're on reddit/discord...

@matthey

Quote:

matthey wrote: You mentioned you were already using Frank Wille's VASM assembler which is a cross assembler that supports PPC. The VBCC cross compiler, and VASM the assembler for it, not only support PPC but multiple Amiga targets (PPC MorphOS, PPC AmigaOS 4, PPC WarpOS and PPC PowerUP). http://sun.hasenbraten.de/vbcc/

I didn't know about this, but Frank has been creating windows executables since 1.8j with each release. Which means I don't have to build vasmppc_std.exe for Windows myself!
It's right there at his site!

I found a HelloWorld ASM code for MorphOS on Aminet and managed to build it directly on Windows. Now just to run it, somehow, without the HW...


I thought I saw something about PPC in WInUAE, so I'll go take a closer look. It'd be super ideal if I could run the PPC executable straight from within WinUAE !

EDIT: Indeed, WinUAE supports PPC, so I just need to figure out how to configure it and then my Dev Environment will be ready.

Last edited by Heimdall on 11-Feb-2025 at 02:41 PM.

Heimdall Quote:

I didn't know about this, but Frank has been creating windows executables since 1.8j with each release. Which means I don't have to build vasmppc_std.exe for Windows myself! It's right there at his site!

Frank is awesome and VBCC/VASM supports all the Amiga division and flavors despite the problems it has caused. This comes from Frank who programmed his PhxAss assembler and many games in 68k assembly.

Heimdall Quote:

I found a HelloWorld ASM code for MorphOS on Aminet and managed to build it directly on Windows. Now just to run it, somehow, without the HW... I thought I saw something about PPC in WInUAE, so I'll go take a closer look. It'd be super ideal if I could run the PPC executable straight from within WinUAE ! EDIT: Indeed, WinUAE supports PPC, so I just need to figure out how to configure it and then my Dev Environment will be ready.

Right. WinUAE supports PPC but you need a PPC OS and kickstart/ROMs. The software needed is more expensive than RPi hardware and more difficult to obtain than 68k versions. PPC hardware is ridiculously expensive considering the lack of performance. The best value for PPC hardware is old PPC Mac hardware which MorphOS runs on and old PPC consoles which no AmigaOS runs on. There was a leaked AmigaOS 4 release for the PS3 but it was missing too many drivers and Sony dropped support for 3rd party OSs. The PPC Cell CPU was very difficult to program anyway although you seem to like the challenge of hardware purgatory. The PPC Nintendo consoles used PPC G3 CPU cores with customized and upgraded SIMD units that were much easier to program and more desktop like. They would make easier and more practical homebrew systems but I have not seen AmigaOS support for them yet.