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From: Robert Swierczek <rmswierczek@gmail.com>
To: TUHS main list <tuhs@minnie.tuhs.org>
Subject: [TUHS] New project to recreate the B compiler for the PDP-11
Date: Tue, 23 Apr 2019 18:11:01 -0400	[thread overview]
Message-ID: <CAAFR5pbE5mX25qzwZMp9BoGxS--dPn0CRm-ziskHDNkG5wO8kA@mail.gmail.com> (raw)

I just started a project to recreate the B compiler for the PDP-11 as
authentically as possible, given the few fragments that remain and
some educated guesswork.  It should be fun (for various definitions of
fun).

Here is the repository  https://github.com/rswier/pdp11-B

I have borrowed some tools from Warren's
https://github.com/DoctorWkt/unix-jun72

I have made a good start at reverse engineering the B run time library
in /usr/lib/libb.a.  I have tried to make the source match the same
style as the earliest C library found on the last1120c-bits tape.  The
remaining functions in libb.a include printf and printn which appear
to be written in B.  This should provide more clues needed to create
the compiler.

I am also tackling the dis-assembly of the threaded code interpreter
/usr/lib/bilib.a (which at the moment is a big mess on my hard-drive)

Later steps will include creating the B compiler itself by carefully
pruning down the last1120c C compiler.  The fun here will be to
boot-strap the B compiler without help from any existing modern
compilers.  I think TMG will come into play to make that happen.

All are welcome to contribute!

Rob

             reply	other threads:[~2019-04-23 22:12 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-23 22:11 Robert Swierczek [this message]
2019-04-23 22:47 ` Angelo Papenhoff
2019-04-23 23:36   ` Robert Swierczek
2019-04-23 23:12 ` Angelo Papenhoff

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