Cat Machine

Cat Machine is a project where we have designed a custom CPU architecture called "Cat CPU" and implemented it as a virtual machine as full toolset.

You can read more about this project or try it out on the Wiki. Try it out in the playground.

Design

• 32bit CPU.
• Simple instruction set designed to be easy to remember and understand.
• Inspired by old game consoles.
• Designed for making simple games.
• Powerfull, contains simple virtual mode and privledge levels.

Toolset

Installing CLI tools (NuGet global tools)

The Catnip compiler, Cat assembler, and launcher are currently distributed as .NET global tools:

dotnet tool install --global CatMachine.Catnip.Compiler
dotnet tool install --global CatMachine.CatAssembler
dotnet tool install --global CatMachine.Launcher

After install, use:

• nipcompile for Catnip compilation
• catasm for Cat assembly
• catlaunch to run/debug ROMs

Cat VM

The Cat VM is where you'll be running your applications. It simulates the architecture and provides debugging tools.

Try running a test application in our ASM playground.

It lives in the CatVM folder.

Cat Assembler (ASM Reference)

The Cat Assembler is an assembler for a custom flavour of assembly language designed specifically for this project. It assembles into a binary file which represents the ROM which is loaded into memory on startup.

Try it out in our ASM playground.

It lives in the CatAssembler folder.

Catnip (Reference)

Catnip is a high-level programming language designed specifically for programming the Cat VM. It compiles into Cat Assembly.

It lives in the Catnip folder.

Catnip Language Server

Low priority project

A language server for Catnip is available in Catnip.LanguageServer. It uses stdio and provides diagnostics, hover, go-to-definition, document symbols, completion, and semantic tokens.

Run it with:

dotnet run --project Catnip.LanguageServer/Catnip.LanguageServer.csproj

Neovim (nvim-lspconfig) example:

require('lspconfig').catnip_ls.setup {
  cmd = { "dotnet", "run", "--project", "/path/to/CatMachine/Catnip.LanguageServer/Catnip.LanguageServer.csproj" },
  filetypes = { "catnip" },
}

VS Code (settings.json) example:

{
  "catnip.languageServer.command": [
    "dotnet",
    "run",
    "--project",
    "/path/to/CatMachine/Catnip.LanguageServer/Catnip.LanguageServer.csproj"
  ]
}

CatLLVM

Low priority project

• Generated ASM will be inefficient

CatLLVM is an LLVM-IR backend for the Cat VM. It accepts LLVM IR text (.ll) and emits Cat Assembly, letting you target CatVM from any LLVM frontend (clang, rustc, etc.):

clang -S -emit-llvm -O0 -m32 -ffreestanding -nostdlib \
      -target i386-unknown-none source.c -o source.ll
dotnet run --project CatLLVM    -- source.ll -o source.cat
catasm source.cat -o source.bin
catlaunch run --rom source.bin

It lives in the CatLLVM folder. See CatLLVM/README.md for the supported IR subset and calling convention; see ExampleProjects/LlvmTest/ for worked examples.