README.md

Opcode constant generator for C, C++ and Rust programming languages

A python script for generating enums with opcode constants based on YAML file definition. It may be useful for virtual machine developers. Defining opcodes in external file instead of direct C++/Rust enum has some advantages:

1. It is easier to read. Definition file contains only relevant information, no C++ code.
2. You can automate a documentation building.
3. Opcode definition is isolated from your virtual machine implementation, so you can use it in non-C++ implementation (of course you'll have to modify this script a little bit).

Written on Python 3.

Installation

Execute the following command to install dependencies:

pip install -r requirements.txt

Usage

Copy the opcodes.example.yaml file to your application's folder, define all the opcodes you need in this file. Then run the script with the following arguments:

python main.py <opcode-list> <language> [--output path/to/file]

where opcode-list is a path to file with opcodes (.yaml file); language is one of the following options: c, cpp, rust; --output specified the output file path. If the output option is not provided then result will be printed to the standard output.

The result may look like this:

enum _GeneratedOpCodes {
    OPCODE_NOP = 0x00,
    OPCODE_B = 0xA0,
    OPCODE_BZ = 0xA1,
    OPCODE_B_FALSE = 0xA1 /* alias for BZ */,
    OPCODE_B_ZERO = 0xA1 /* alias for BZ */,
    OPCODE_B_NULL = 0xA1 /* alias for BZ */,
    OPCODE_BNZ = 0xA2,
    OPCODE_B_TRUE = 0xA2 /* alias for BNZ */,
    OPCODE_B_NOT_ZERO = 0xA2 /* alias for BNZ */,
    OPCODE_B_NOT_NULL = 0xA2 /* alias for BNZ */
};