32-bit RISC-V Emulator in Rust

This is a RISC-V emulator supoorting RV32I instruction set written in Rust, inspired by Francis Stokes's RISC-V Emulator in Typescript. (He made a fascinating series of videos on this topic!) You can either run this repository as a stand-alone binary or a WASM package, which can be embeded to a website. Try it out here!

Usage

Make sure you have rust developing environment installed. RISC-V GNU Toolchain is not necessary. If the toolchain is not found in your PATH, a docker image containing the toolchain will be pulled automatically.

Stand alone binary

The emulator supports running customized C program. To run your own C program, perform the following steps:

1. Put the C file in test_payloads/src directory
2. Run make in the top directory
3. Run cargo run test_payloads/build/[filename].bin

Note:

• The only output method is using register/memory dump. Currently no privileged level is supported so no syscall can be handled, which means functions like printf are not allowed.
• Memory starts at 0x8000_0000
• .bin suffix is necessary, which will be automatically generated along with the elf file.

WASM Package

The emulator can also be compiled into a WASM lib. Run make in the top directory and you will get a pkg directory containing the library. To use the library inside JS/TS, copy the pkg directory to your project and import it as the following:

import init, { emulate } from "./pkg/rv_emu_rs.js";

init()
    .then(() => {
        // your codes here...

        ...
        // romArray is a u8 array containing binary codes
        // memSize is the length of memory dump
        emulate(romArray, memSize);
        ...
    });