src/test/ui/issues/issue-14936.rs

   1 // build-pass (FIXME(62277): could be check-pass?)
   2 #![allow(unused_macros)]
   3 #![allow(dead_code)]
   4 #![feature(asm)]
   5
   6 type History = Vec<&'static str>;
   7
   8 fn wrap<A>(x:A, which: &'static str, history: &mut History) -> A {
   9     history.push(which);
  10     x
  11 }
  12
  13 macro_rules! demo {
  14     ( $output_constraint:tt ) => {
  15         {
  16             let mut x: isize = 0;
  17             let y: isize = 1;
  18
  19             let mut history: History = vec![];
  20             unsafe {
  21                 asm!("mov ($1), $0"
  22                      : $output_constraint (*wrap(&mut x, "out", &mut history))
  23                      : "r"(&wrap(y, "in", &mut history))
  24                      :: "volatile");
  25             }
  26             assert_eq!((x,y), (1,1));
  27             let b: &[_] = &["out", "in"];
  28             assert_eq!(history, b);
  29         }
  30     }
  31 }
  32
  33 #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
  34 fn main() {
  35     fn out_write_only_expr_then_in_expr() {
  36         demo!("=r")
  37     }
  38
  39     fn out_read_write_expr_then_in_expr() {
  40         demo!("+r")
  41     }
  42
  43     out_write_only_expr_then_in_expr();
  44     out_read_write_expr_then_in_expr();
  45 }
  46
  47 #[cfg(all(not(target_arch = "x86"), not(target_arch = "x86_64")))]
  48 pub fn main() {}