tests/assembly/niche-prefer-zero.rs

   1 // Check that niche selection prefers zero and that jumps are optimized away.
   2 // See https://github.com/rust-lang/rust/pull/87794
   3 // assembly-output: emit-asm
   4 // only-x86
   5 // compile-flags: -Copt-level=3
   6
   7 #![crate_type = "lib"]
   8
   9 #[repr(u8)]
  10 pub enum Size {
  11     One = 1,
  12     Two = 2,
  13     Three = 3,
  14 }
  15
  16 #[no_mangle]
  17 pub fn handle(x: Option<Size>) -> u8 {
  18     match x {
  19         None => 0,
  20         Some(size) => size as u8,
  21     }
  22 }
  23
  24 // There should be no jumps in output
  25 // CHECK-NOT: j