// only-x86_64 #![feature(repr_simd, never_type)] use std::arch::asm; #[repr(simd)] struct SimdNonCopy(f32, f32, f32, f32); fn main() { unsafe { // Inputs must be initialized let x: u64; asm!("{}", in(reg) x); //~^ ERROR E0381 let mut y: u64; asm!("{}", inout(reg) y); //~^ ERROR E0381 let _ = y; // Outputs require mutable places let v: Vec = vec![0, 1, 2]; //~^ ERROR cannot borrow `v` as mutable, as it is not declared as mutable asm!("{}", in(reg) v[0]); asm!("{}", out(reg) v[0]); asm!("{}", inout(reg) v[0]); // Sym operands must point to a function or static const C: i32 = 0; static S: i32 = 0; asm!("{}", sym S); asm!("{}", sym main); // Register operands must be Copy // Register operands must be integers, floats, SIMD vectors, pointers or // function pointers. asm!("{}", in(reg) 0i64); asm!("{}", in(reg) 0f64); asm!("{}", in(xmm_reg) std::arch::x86_64::_mm_setzero_ps()); asm!("{}", in(reg) 0 as *const u8); asm!("{}", in(reg) 0 as *mut u8); asm!("{}", in(reg) main as fn()); // Register inputs (but not outputs) allow references and function types let mut f = main; let mut r = &mut 0; asm!("{}", in(reg) f); asm!("{}", in(reg) r); let _ = (f, r); // Type checks ignore never type let u: ! = unreachable!(); asm!("{}", in(reg) u); } }