I ran across an article “The Fortran I Compiler” by David Padua in Computing in Science and Engineering, Volume 2, Number 1, (January/February 2000). It begins, “The Fortran I compiler was the first demonstration that it is possible to automatically generate efficient machine code from high-level languages. It has thus been enormously influential. This article presents a brief description of the techniques used in the Fortran I compiler for the parsing of expressions, loop optimization, and register allocation.”
I contacted David to see if by any chance he knew of someone with a copy of the source code. He didn’t but he and his colleague Sam Midkiff suggested contacting retired IBMers Fran Allen or Marty Hopkins.