rust/src/test/run-pass/asm-out-assign.rs

36 lines
1.0 KiB
Rust

// Copyright 2012-2013-2014 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.
// ignore-fast #[feature] doesn't work with check-fast
#[feature(asm)];
#[cfg(target_arch = "x86")]
#[cfg(target_arch = "x86_64")]
pub fn main() {
let x: int;
unsafe {
// Treat the output as initialization.
asm!("mov $1, $0" : "=r"(x) : "r"(5u));
}
assert_eq!(x, 5);
let mut x = x + 1;
assert_eq!(x, 6);
unsafe {
// Assignment to mutable.
asm!("mov $1, $0" : "=r"(x) : "r"(x + 7));
}
assert_eq!(x, 13);
}
#[cfg(not(target_arch = "x86"), not(target_arch = "x86_64"))]
pub fn main() {}