dasm

A tiny, zero dependency assembler that currently supports x86 and amd64.

Note

dasm has a goal of acting as a lightweight, simple instructions for compilers.

If you want a higher-level library or something more comprehensive, there's other great solutions like Iced or dynasm-rs.

How it works

Code generation doesn't have to be hard. This just provides explicit functions for generating instructions.
No abstractions through macros, or some DSL you need to learn. Just functions.

Example

use dasm::tier::raw::amd64::*;

let rax = 0;
let rsi = 6; // Argument 2
let rdi = 7; // Argument 1

let asm = [
	&mov_r64_r64(rax, rdi) as &[u8],
	&add_r64_r64(rax, rsi),
	&ret()
].concat();

// Allocate an executable memory block
let mmapped = dasm::mmap::Mmap::exec(&asm)
	.expect("Failed to mmap");

// Simply cast that memory into a function to call it.
let adder: extern "C" fn(x: u64, y: u64) -> u64 = unsafe { std::mem::transmute(mmapped.as_ptr()) };
assert_eq!(adder(5, 200), 205);

There's also an example showcasing a tiny AOT compiled lisp at examples/tinylisp.

Why

All of the other solutions are either too big for my usecase (LLVM), too complex (Cranelift) or have too many abstractions.
Sometimes, you don't need all of that - you just need to write some assembly.
That's what dasm is for.

Of course - No shade to any other library. Anyone can use the tool they prefer.