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vuurraaf/v

A complete toolchain for VuurRaaf, written in V from scratch: a compiler, an assembler, a linker, and a stack-based runtime. Everything — including the object file format and the virtual machine — lives in this repository.

.vr  --compiler-->  .vobj  --linker-->  .vbin  --vm-->  output
.vasm --assembler--> .vobj

Build

Requires V (v in your PATH).

v -o bin/vr .        # build the toolchain
./bin/vr up          # or rebuild from inside the toolchain
./bin/vr symlink     # optionally symlink bin/vr into your PATH

Note: build with v . from the project root. Building via an explicit file or path argument makes V pick tcc without the Boehm GC, a combination that miscompiles this codebase (vr up already does the right thing).

Usage

vr compile <file.vr> [-o out.vobj]          source  -> object
vr assemble <file.vasm> [-o out.vobj]       assembly -> object
vr link <a.vobj> [more.vobj ...] [-o out]   objects -> executable (.vbin)
vr run <file.vr|file.vbin>                  compile+link+run, or run a binary
vr debug <file.vr|file.vbin>                run with an instruction trace
vr test <file.vr>                           run every test_* function
vr bench <file.vr> [iterations]             benchmark main()
vr clean                                    remove .vobj/.vbin artifacts
vr up                                       rebuild bin/vr
vr symlink                                  link bin/vr into your PATH
vr config [set <key> <value>]               toolchain config (outdir, verbose)
vr info | loader | alloc | version | help

Quick start:

./bin/vr run examples/hello.vr        # run a program
./bin/vr test examples/tests.vr       # run the tests (one fails on purpose)
./bin/vr debug examples/hello.vr      # watch every bytecode instruction

# the assembler path
./bin/vr assemble examples/math.vasm -o math.vobj
./bin/vr link math.vobj -o math.vbin
./bin/vr run math.vbin

# multi-file programs (functions in one file may call functions in another)
./bin/vr compile examples/lib.vr -o lib.vobj
./bin/vr compile examples/use_lib.vr -o use_lib.vobj
./bin/vr link lib.vobj use_lib.vobj -o use_lib.vbin
./bin/vr run use_lib.vbin

The VuurRaaf language

A small, V-flavored language. Everything is a 64-bit integer or a string (strings concatenate with + and compare with ==/!=; print/println accept both).

fn greet(name) {
    println("hello, " + name + "!")
}

fn fib(n) {
    if n < 2 {
        return n
    }
    return fib(n - 1) + fib(n - 2)
}

fn main() {
    let x = 6 * 7                       // let with type inference
    assert x == 42                       // checked by the vm at runtime
    let big = x > 40 and x < 50          // and / or / not, short-circuiting
    if big {
        println("x is big")
    } else {
        println("x is small")
    }
    let i = 0
    while i < 3 {
        println("counting " + i)         // "counting 0", ...
        i = i + 1
    }
    println(fib(10))                     // 55
}
  • functions: fn name(a, b) { ... } with return expr
  • variables: let name = expr, reassignment name = expr
  • operators: + - * / %, == != < <= > >=, and or not, unary -
  • statements: let, assignment, if/else, while, return, assert, calls, print(...) / println(...)
  • comments: //

Assembly

.vasm files talk to the VM directly. Labels, .global exports, and the full opcode set:

; comment
.global main
main:
    push_int 42
    call helper 1        ; call <target> <argc>
    println
    halt

.global helper
helper:
    enter 0              ; reserve extra locals (args were copied in by `call`)
    load 0
    retv

Opcodes: halt push_int push_str load store pop dup add sub mul div mod neg eq ne lt le gt ge and or not jmp jz jnz call ret retv print println assert enter.

Formats

  • VROBJ (.vobj) — linker input: bytecode, exported symbols (function name -> code offset), string constants, and relocations (call sites and string references).
  • VRBIN (.vbin) — the executable: function table, string table, bytecode.

Architecture

module role
compiler/ lexer, recursive-descent parser, bytecode codegen (VROBJ)
assembler/ .vasm -> VROBJ
linker/ resolves relocations, rebases strings, emits VRBIN
vm/ stack VM: tagged values, call frames, string heap, tracing
obj/ VROBJ/VRBIN binary formats
bin/ small standalone tools: tl_alloc.v, tl_loader.v

The VM is a stack machine with 64-bit tagged values (numbers are stored shifted left so no integer collides with a string handle). Calls push a frame (return address, base pointer, argc), copy arguments into local slots, and reserve extra locals with enter n. vr debug prints every instruction with the stack contents.

Repository layout

main.v               CLI entry point (vr <command> ...)
v.mod                module definition
compiler/ assembler/ linker/ vm/ obj/   the toolchain itself
bin/                 built binary + standalone tools
examples/            runnable examples (hello, lib, asm, tests, fib)