ziyao233 / barv

RISC-V VM in Bash

barv

A rv32i virtual machine, implemented in Bash.

Dependency

Bash and coreutils. I did this mess on Alpine Linux edge with busybox and bash 5.2.26 and everything worked well.

Usage

 $ barv.sh BINARY

Memory Map and Boot Up

The binary specified as argument will be loaded into memory, starting from 0x00000000. PC is set to 0 when the virtual machine starts.

Environment Call

Some functionalities are provided through ecall. a0 contains ecall number.

ecall Number

• 0: system shutdown (exit the VM)
• 1: register dump (dump out a1)
• 2: ASCII putchar (character is stored in a1)

ebreak could be used to print a snapshot of registers.

Tests

barv has passed a port of riscv-tests. But there are still bugs I think.