tests/codegen/asm-multiple-options.rs

   1 // compile-flags: -O
   2 // only-x86_64
   3
   4 #![crate_type = "rlib"]
   5
   6 use std::arch::asm;
   7
   8 // CHECK-LABEL: @pure
   9 // CHECK-NOT: asm
  10 // CHECK: ret void
  11 #[no_mangle]
  12 pub unsafe fn pure(x: i32) {
  13     let y: i32;
  14     asm!("", out("ax") y, in("cx") x, options(pure), options(nomem));
  15 }
  16
  17 pub static mut VAR: i32 = 0;
  18 pub static mut DUMMY_OUTPUT: i32 = 0;
  19
  20 // CHECK-LABEL: @readonly
  21 // CHECK: call i32 asm
  22 // CHECK: ret i32 1
  23 #[no_mangle]
  24 pub unsafe fn readonly() -> i32 {
  25     VAR = 1;
  26     asm!("", out("ax") DUMMY_OUTPUT, options(pure), options(readonly));
  27     VAR
  28 }
  29
  30 // CHECK-LABEL: @nomem
  31 // CHECK-NOT: store
  32 // CHECK: call i32 asm
  33 // CHECK: store
  34 // CHECK: ret i32 2
  35 #[no_mangle]
  36 pub unsafe fn nomem() -> i32 {
  37     VAR = 1;
  38     asm!("", out("ax") DUMMY_OUTPUT, options(pure), options(nomem));
  39     VAR = 2;
  40     VAR
  41 }
  42
  43 // CHECK-LABEL: @not_nomem
  44 // CHECK: store
  45 // CHECK: call i32 asm
  46 // CHECK: store
  47 // CHECK: ret i32 2
  48 #[no_mangle]
  49 pub unsafe fn not_nomem() -> i32 {
  50     VAR = 1;
  51     asm!("", out("ax") DUMMY_OUTPUT, options(pure), options(readonly));
  52     VAR = 2;
  53     VAR
  54 }