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