uplm80 - PL/M-80 Compiler

A modern PL/M-80 compiler targeting Zilog Z80 assembly language.

PL/M-80 was the primary systems programming language for CP/M and other 8080/Z80 operating systems. This compiler can rebuild original CP/M utilities from their PL/M source code.

Repository: https://github.com/avwohl/uplm80

Features

• Full PL/M-80 language support
• Targets Z80 instruction
• Multi-file compilation with cross-module optimization
• Multiple optimization passes (AST optimizer, upeepz80 peephole optimizer)
• Generates relocatable object files compatible with standard CP/M linkers
• Calls procedures the way Intel's PL/M-80 does, so its code links with assembly and objects written for PL/M-80
• Produces code competitive with the original Digital Research compiler

Code Quality

Compiled output is comparable to the original Digital Research PL/M-80 compiler:

Installation

pip install uplm80 um80 upeepz80

From source: git clone https://github.com/avwohl/uplm80.git && cd uplm80 && pip install -e . See INSTALL.md and README_RASPBERRY_PI.md for more.

Usage

uplm80 input.plm -o output.mac                  # compile (or: python -m uplm80.compiler)
uplm80 main.plm helper.plm lib.plm -o out.mac   # multi-file, cross-module optimization
um80 output.mac                                 # assemble to .rel
um80 x0100.asm                                  # MON1 equ 5 and the rest
ul80 -o program.com output.rel x0100.rel        # link to CP/M .com

Options:

• -m cpm|bare|mpm - runtime mode (default cpm); bare rebuilds DRI's utilities, mpm makes MP/M II .PRL/.RSP/.SPR modules
• -O 0|1|2|3 - optimization level (default 2)
• -D SYMBOL - define a conditional compilation symbol (repeatable)

Each module carries the runtime routines it uses; link with it only what defines its EXTERNALs. See examples/hellocpm.plm and the drop-in docs/example.Makefile (contributed by Martin Homuth-Rosemann, @Ho-Ro).

Documentation

• docs/language.md - rules the compiler checks, as Intel's V3.1 does; $IF/$SET conditional compilation
• docs/calling_convention.md - calling convention, writing assembly PL/M calls, runtime routines, names in the output
• docs/runtime_modes.md - CP/M, bare and MP/M modes, memory layout, how procedure locals share ??AUTO
• docs/multi_file_compilation.md - compiling several modules together
• docs/intel_oracle.md - differential testing against Intel's PL/M-80 V3.1, and the known differences
• docs/debug_info.md - -g: source-line and variable markers for a debugger (udb80, GDB); the code does not change
• docs/BDOS_REFERENCE.md - calling CP/M BDOS from PL/M-80
• docs/project_structure.md - source files and what each does
• docs/PLM80_FEATURE_INDEX.md - language features and their tests
• CHANGELOG.md - releases and known issues

The front end is generated from plox grammars; peephole optimization is upeepz80.

License

GPL v3.0 or later - see LICENSE. Issues and pull requests are welcome.

Related Projects

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