stacky_mcstackface

Stack Machine VM

A stack based virtual machine and compiler based off of the instruction set outlined in this book.

Rationale and Design Considerations

• I wanted to write my own FORTH, but didn't want to go through the trouble of learning a real assembly environment.
• You don't tell me what to do! IM JUST HAVING FUN OK!?

Architecture

• vm.IP - Next instruction that will be processed if you execute vm.tick().
• vm.RSP - Points to next free slot in the return stack.
• vm.PSP - Points to next free slot in the parameter stack. Often just called "The Stack".

Road Map

• [X] Memory.
• [X] Really basic compiler.
• [X] Instruction set.
• [ ] Add support for labels to compiler.
• [ ] Interupts.
• [ ] vm.subscribe(addr) to observe memory address changes.
• [ ] I/O.
• [ ] FORTH compiler.

Installation

1. npm install
2. typings install
3. (Optional) npm test to verify installation.

Usage

import { VM, Compiler } from "stacky_mcstackface";

// Instantiate a 64 word (128 byte) virtual machine.
    let vm = new VM(64); // 64 words (16 bit each).

// Create a compiler instance.
    let compileFn = Compiler();

// Compile text source code into numeric byte code.
    let program = compileFn(`PUSH 1 PUSH 5 ADD 4 SUB`);
    // => [ 2, 1, 2, 5, 8, 4, 9 ];

// Load the VM.
   vm.load(program);

// Execute "cycles"
    vm.tick(); // => PUSH 1
    vm.tick(); // => PUSH 5
    vm.tick(); // => ADD  4
    vm.tick(); // => SUB

Instruction Set

See documentation in default_instructions.ts.