fvm

Fantasy Virtual Machine

A 64-bit stack-based virtual machine and its assembler, created for fun.

Build

FVM includes two parts: the virtual machine and the assembler.

The build the assembler, you need to intall CHICKEN Scheme first.

For example, on Arch Linux:

sudo pacman -S chicken

Then install CHICKEN Scheme dependencies:

sudo chicken-install matchable srfi-69 srfi-4

Then run make, which will build both components:

make

If successful, you will see two executables, the virtual machine fvm and the assembler fvm-as.

Run

After writing the assembly code (examples can be found in the examples/ directory), first run the assembler:

./fvm-as input.asm bytecode.bin

This will generate the bytecode file output.bin. Then run the virtual machine:

./fvm bytecode.bin

Registers

FVM contains 4 registers:

• SP: stack pointer
• BP：base pointer
• PC：program counter
• RV: returned value

There are no general-purpose registers; all operations happen on the stack.

Opcodes

All opcodes are single-byte, except for immediate value instructions.

See src/fvm.h for a full list of opcodes.