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// build-pass
#![allow(unused_macros)]
#![allow(dead_code)]
#![feature(asm)]
type History = Vec<&'static str>;
fn wrap<A>(x:A, which: &'static str, history: &mut History) -> A {
history.push(which);
x
}
macro_rules! demo {
( $output_constraint:tt ) => {
{
let mut x: isize = 0;
let y: isize = 1;
let mut history: History = vec![];
unsafe {
asm!("mov ($1), $0"
: $output_constraint (*wrap(&mut x, "out", &mut history))
: "r"(&wrap(y, "in", &mut history))
:: "volatile");
}
assert_eq!((x,y), (1,1));
let b: &[_] = &["out", "in"];
assert_eq!(history, b);
}
}
}
#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
fn main() {
fn out_write_only_expr_then_in_expr() {
demo!("=r")
}
fn out_read_write_expr_then_in_expr() {
demo!("+r")
}
out_write_only_expr_then_in_expr();
out_read_write_expr_then_in_expr();
}
#[cfg(all(not(target_arch = "x86"), not(target_arch = "x86_64")))]
pub fn main() {}
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