PDP-11 FORTRAN IV

This document outlines the design and functional specifications for the PDP-11 FORTRAN IV system, consisting of a compiler (Version 4A) and an Object Time System (Version 20A). The guide includes:

• System Overview: Usage, market, design philosophy, and hardware/software requirements (minimum 8K core, Disk Monitor/DOS).
• Conventions and Standards: Labeling schemes, register usage, data formats (integer, real, double precision, complex, byte, logical), and calling conventions.
• POLISH Implementation: Details on threaded code generation using the POLISH method for efficient expression evaluation.
• Data Structures: Descriptions of compiler tables, including the main symbol table, common table, and array descriptor blocks.
• Input/Output: Overview of compiler I/O and runtime I/O facilities.
• Language Support: Features, exceptions, and differences from the ANSI FORTRAN IV standard.
• System Build: Detailed instructions for assembling and linking the compiler and object time system modules.