HolyCross

A modern cross-platform HolyC compiler written in Zig that enables developers to write TempleOS software from Linux, Windows, and macOS.

Project Status

🚀 Functional Compiler 🚀

The HolyCross compiler can now compile HolyC programs to working x64 Linux executables!

Current Capabilities

• ✅ Full lexer with all HolyC token types
• ✅ Complete recursive descent parser with Pratt expression parsing
• ✅ Preprocessor with #define, #ifdef, #include support
• ✅ Semantic analysis with type checking and symbol resolution
• ✅ IR generation and x64 code generation
• ✅ Inline assembly support (asm { } blocks)
• ✅ Multi-variable declarations (I64 a, b, c;)
• ✅ Classes, unions, arrays, pointers
• ✅ Control flow (if, while, for, do-while, switch)
• ✅ Function calls and returns
• ✅ Binary operators, unary operators, assignments
• ⏳ Full TempleOS compatibility (in progress)

See ARCHITECTURE.md for detailed compiler architecture and design.

About

HolyC is the programming language created by Terry A. Davis for TempleOS. This project aims to bring HolyC to modern development environments while maintaining compatibility with TempleOS binaries.

Goals

1. Compile HolyC source code to working binaries
2. Support native Linux x64 execution for rapid development
3. Generate TempleOS-compatible .BIN executables
4. Handle core HolyC language features (classes, inline assembly, #exe directive)
5. Enable compilation of significant TempleOS applications

Building

Prerequisites

• Zig 0.16.0 or later
• Linux x64 (primary development platform)
• Windows or macOS (future support)

Build Instructions

# Clone the repository
git clone <your-repo-url>
cd HolyCross

# Build the compiler
zig build

# Run the compiler
./zig-out/bin/holycc examples/hello.hc

# Run tests
zig build test

# Format code
zig build fmt

Usage

Quick Start

Create a simple HolyC program:

// hello.hc
I64 main()
{
    return 42;
}

Compile and run:

# Compile
./zig-out/bin/holycc hello.hc

# Run
./a.out
echo $?  # Should print: 42

More Examples

// Multi-variable declarations
I64 x = 10, y = 20, z = 30;

// Inline assembly
I64 GetValue()
{
    asm {
        MOV RAX, 42
    }
    return 0;
}

// Classes
class Point
{
    I64 x, y;
};

// Functions
I64 Add(I64 a, I64 b)
{
    return a + b;
}

Command Line Options

# Compile a HolyC file
holycc input.hc

# Specify output file  
holycc input.hc -o output

# Show version
holycc --version

# Show help
holycc --help

Project Structure

HolyCross/
├── src/                    # Source code
│   ├── main.zig           # Entry point
│   ├── preprocessor/      # Preprocessor (#define, #ifdef, etc.)
│   ├── lexer/             # Lexical analysis
│   ├── parser/            # Syntax analysis (AST generation)
│   ├── semantic/          # Semantic analysis & type checking
│   ├── codegen/           # IR generation & x64 code generation
│   ├── assembler/         # Inline assembly support
│   └── runtime/           # Runtime support (planned)
├── tests/                  # Test suites
├── examples/               # Example HolyC programs
├── ARCHITECTURE.md         # Compiler architecture documentation
├── PLAN.md                # Development roadmap
├── LICENSE                # LGPL v3
└── README.md              # This file

Development Status

The project has moved beyond the initial phases:

• Phase 0-2: Foundation & Hello World (✅ Complete)
• Phase 3-5: Core Language Features (✅ Complete)
• Phase 6-7: Advanced Features (🚧 In Progress)
• Phase 8: TempleOS Binary Format (⏳ Planned)
• Phase 9+: Optimization & Polish (⏳ Planned)

Recent Accomplishments

• Inline assembly support with asm { } blocks
• Multi-variable declarations (local and global)
• Full preprocessor with conditional compilation
• Complete x64 code generation pipeline
• Comprehensive test suite

See PLAN.md for detailed roadmap and ARCHITECTURE.md for technical details.

Contributing

This is currently a personal learning project. Contributions, suggestions, and bug reports are welcome once the core compiler reaches Phase 2.

License

This project is licensed under the GNU Lesser General Public License v3.0 (LGPL-3.0). See LICENSE for details.

Acknowledgments

• Terry A. Davis: Creator of TempleOS and HolyC
• Zeal OS Team: Continued development and documentation
• Zig Community: Excellent language and tooling

Resources

• Compiler Architecture - Detailed technical documentation
• Development Plan - Roadmap and milestones
• TempleOS Archive - Original TempleOS source
• ZealOS - Modern TempleOS continuation
• HolyC Language Reference - Inline assembly documentation

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"God said 640x480 16 color was a covenant like the rainbow." - Terry A. Davis