ucow

A Python-based Cowgol compiler targeting Z80 CP/M.

Usage

Single File Compilation

# Compile a Cowgol source file to Z80 assembly
python3 -m src.main source.cow -o output.mac

# Assemble with um80
um80 output.mac

# Link with ul80
ul80 output.rel -o output.com

Multi-File Compilation

Compile multiple Cowgol source files together in a single compiler run:

# Compile all modules together into one assembly file
python3 -m src.main main.cow utils.cow math.cow -o program.mac

# Assemble and link
um80 program.mac
ul80 program.rel -o program.com

This approach enables workspace optimization: the compiler analyzes the call graph across all modules to determine which subroutines can never be active simultaneously. Subroutines that don't overlap in the call tree share local variable storage, significantly reducing data segment size.

For example, if sub_a and sub_b each use 100 bytes of locals but never call each other, they share the same 100 bytes instead of using 200 bytes total.

Use --graph-debug to see the call graph analysis:

python3 -m src.main --graph-debug main.cow lib.cow -o output.mac

Include Paths

Use -I to add directories to the include search path:

python3 -m src.main -I ./lib -I ./include source.cow -o output.mac

Compiler Options

Requirements

• Python 3
• um80 (Z80 assembler)
• ul80 (linker)
• cpmemu (for testing)

Related Projects

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