File	Date	Author	Commit
original	2017-12-16	Daniel Weaver	[b6dcc4] Initial commit
port	2017-12-16	Daniel Weaver	[b6dcc4] Initial commit
source	2017-12-16	Daniel Weaver	[b6dcc4] Initial commit
COPYING	2017-12-16	Daniel Weaver	[b6dcc4] Initial commit
README	2017-12-16	Daniel Weaver	[b6dcc4] Initial commit

Read Me

XPL compiler for the PDP-10.

This compiler was written in the mid-70's by Richard L. Brisbey II and
R. H. Hey.  Based on work done by William M. McKeeman, James J. Horning
and David B. Wortman and described in their book "A Compiler Generator".

This XPL compiler is the only know surviving version of the original
XCOM version 4.  This compiler uses LALR parsing tables.  Unfortunately
the BNF analyzer in this release generates MSP tables and not LALR tables.

This PDP-10 compiler was placed in the public domain and released through
DECUS.  It was found under the title DECUS.20-0122.

The original compiler requires a PDP-10 to run but nexcom.xpl is a port
of the original compiler to be compiled with the XPL to C translator
found here:  https://sourceforge.net/projects/xpl-compiler/
The nexcom.xpl cross compiler requires 64-bit integer support on the
host computer.  64-bit integers are used to simulate the 36-bit word
of the PDP-10.