[llvm-dev] LLVM z80 backend and llvm-dis missing?

[Philipp Klaus Krause via llvm-dev]

On 05.10.2016 00:24, Jan Wilmans via llvm-dev wrote:
> Inspired by Jason Turner's talk at  CppCon 2016: Jason Turner “Rich Code
> for Tiny Computers: A Simple Commodore 64 Game in C++17”
> 
> I got interested in writing a Zilog Z80 backend for LLVM. Jason actually
> did no such thing, but instead wrote a x86-to-6502 translator
> (reassembler he calls it) https://github.com/lefticus/x86-to-6502
> 
> So I'm now trying to bootstrap this project.
> 
> Goal:
> - be able to use C++17 (or whatever is supported of that in
> clang-master) on my Z80 based MSX2 computer.
> 
> why? you might ask, well, just because I'm a software engineer and I
> like doing something I have not tried before.
> In the past I have created a PC-to-MSX USB-interface called the 'nowind'
> interface (http://nowind.nl/)
> It is actually a MSX2-compatible cartridge that from the MSX2
> perspective appears to be a diskdrive, but actually the 'disk' is a
> disk-image file on the PC.
> 
> The host-software is written in c++98 and the z80-software (residing in
> flashrom) is written in z80-assembly, which I mastered quite well back then.
> 
> So why am I telling you this?
> I would like to get some pointers on how to get started.
> My development environment is currently windows, but if there is any
> advantage in switching to linux, that is also fine.
> 
> I have gcc/gdb experience but its a little rusty.
> so I started reading http://llvm.org/docs/GettingStarted.html,
> and downloaded http://llvm.org/releases/3.9.0/LLVM-3.9.0-win64.exe
> precompiled binaries to get the hang of the toolchain.
> 
> Couple of questions:
> - First thing I noticed is that clang-dis is not part of the
> pre-compiled package?
> - What is a wise approach, should I compile clang from scratch to get
> clang-dis?
> - are LLVM  backends for clang also in the
> trunk http://llvm.org/git/llvm.git ?
> - should I start by examining and existing backend, if so, where do I
> find one?
> 
> I hope anyone can give me some guidance to bootstrap this... 
> 
> Greetings,
> 
> Jan

The easiest to get C++17 on the Z80 is probably using the experimental
LLVM+SDCC toolchain:
https://sourceforge.net/p/sdcc/mailman/message/35382805/
Though there is still some work to be done it should be much easier to
make useable for you than to get full Z80 support in LLVM itself.

Philipp