rust/src/test/run-pass/intrinsic-atomics.rs

// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

#[abi = "rust-intrinsic"]
extern mod rusti {
    #[legacy_exports];
    fn atomic_cxchg(dst: &mut int, old: int, src: int) -> int;
    fn atomic_cxchg_acq(dst: &mut int, old: int, src: int) -> int;
    fn atomic_cxchg_rel(dst: &mut int, old: int, src: int) -> int;

    fn atomic_xchg(dst: &mut int, src: int) -> int;
    fn atomic_xchg_acq(dst: &mut int, src: int) -> int;
    fn atomic_xchg_rel(dst: &mut int, src: int) -> int;
    
    fn atomic_xadd(dst: &mut int, src: int) -> int;
    fn atomic_xadd_acq(dst: &mut int, src: int) -> int;
    fn atomic_xadd_rel(dst: &mut int, src: int) -> int;
    
    fn atomic_xsub(dst: &mut int, src: int) -> int;
    fn atomic_xsub_acq(dst: &mut int, src: int) -> int;
    fn atomic_xsub_rel(dst: &mut int, src: int) -> int;
}

fn main() {
    unsafe {
        let x = ~mut 1;

        assert rusti::atomic_cxchg(x, 1, 2) == 1;
        assert *x == 2;

        assert rusti::atomic_cxchg_acq(x, 1, 3) == 2;
        assert *x == 2;

        assert rusti::atomic_cxchg_rel(x, 2, 1) == 2;
        assert *x == 1;

        assert rusti::atomic_xchg(x, 0) == 1;
        assert *x == 0;

        assert rusti::atomic_xchg_acq(x, 1) == 0;
        assert *x == 1;

        assert rusti::atomic_xchg_rel(x, 0) == 1;
        assert *x == 0;

        assert rusti::atomic_xadd(x, 1) == 0;
        assert rusti::atomic_xadd_acq(x, 1) == 1;
        assert rusti::atomic_xadd_rel(x, 1) == 2;
        assert *x == 3;

        assert rusti::atomic_xsub(x, 1) == 3;
        assert rusti::atomic_xsub_acq(x, 1) == 2;
        assert rusti::atomic_xsub_rel(x, 1) == 1;
        assert *x == 0;
    }
}