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From: Paul Rubin <no.email@nospam.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Adapting an Ada compiler to generate 8051 code (Again?! ;-)
Date: Tue, 30 Mar 2021 14:48:13 -0700
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"Luke A. Guest" <laguest@archeia.com> writes:
>> there are any really large obstacles to targeting GCC to the 8051
> The biggest obstacles will be the severe lack of registers. But it's
> possible, lm78 for example.

Do  you mean this?  https://www.ti.com/lit/gpn/lm78
I wasn't familiar with it.  It looks awful, a couple special purpose
registers and something like 19 bytes of ram (I didn't look closely).

Does gcc actually generate code for it?  I don't know whether gcc
targets any old-fashioned accumulator machines with no registers.  I
thought it did, but maybe not.  I do know lots of people use it for the
AVR8 / Aruino etc.

It hadn't occurred to me but yeah, maybe gcc is built more around
register architectures and sdcc works differently.  I haven't really
looked.

I know SWEET16 is a 16 bit virtual machine that Steve Wozniak
implemented on the 6502 in the original Apple II, to get higher code
density than 6502 asm code.  It had 16 registers.  Doing something like
that on an 8051 and targeting GCC to it sounds fairly plausible.  I
wouldn't be surprised if it's been done already.

Does a minimal Ada runtime (Ravenscar or whatever) make particular
demands that require much outside-the-compiler support?

Adacore Ada-to-C is proprietary?  Oh well.  I wonder if generating C
output from GCC intermediate code is terribly difficult.