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|
// Compiler:
//
// Run-time:
// status: 0
#[cfg(target_arch = "x86_64")]
use std::arch::{asm, global_asm};
#[cfg(target_arch = "x86_64")]
global_asm!(
"
.global add_asm
add_asm:
mov rax, rdi
add rax, rsi
ret"
);
extern "C" {
fn add_asm(a: i64, b: i64) -> i64;
}
#[cfg(target_arch = "x86_64")]
pub unsafe fn mem_cpy(dst: *mut u8, src: *const u8, len: usize) {
asm!(
"rep movsb",
inout("rdi") dst => _,
inout("rsi") src => _,
inout("rcx") len => _,
options(preserves_flags, nostack)
);
}
#[cfg(target_arch = "x86_64")]
fn asm() {
unsafe {
asm!("nop");
}
let x: u64;
unsafe {
asm!("mov $5, {}",
out(reg) x,
options(att_syntax)
);
}
assert_eq!(x, 5);
let x: u64;
let input: u64 = 42;
unsafe {
asm!("mov {input}, {output}",
"add $1, {output}",
input = in(reg) input,
output = out(reg) x,
options(att_syntax)
);
}
assert_eq!(x, 43);
let x: u64;
unsafe {
asm!("mov {}, 6",
out(reg) x,
);
}
assert_eq!(x, 6);
let x: u64;
let input: u64 = 42;
unsafe {
asm!("mov {output}, {input}",
"add {output}, 1",
input = in(reg) input,
output = out(reg) x,
);
}
assert_eq!(x, 43);
// check inout(reg_class) x
let mut x: u64 = 42;
unsafe {
asm!("add {0}, {0}",
inout(reg) x
);
}
assert_eq!(x, 84);
// check inout("reg") x
let mut x: u64 = 42;
unsafe {
asm!("add r11, r11",
inout("r11") x
);
}
assert_eq!(x, 84);
// check a mix of
// in("reg")
// inout(class) x => y
// inout (class) x
let x: u64 = 702;
let y: u64 = 100;
let res: u64;
let mut rem: u64 = 0;
unsafe {
asm!("div r11",
in("r11") y,
inout("eax") x => res,
inout("edx") rem,
);
}
assert_eq!(res, 7);
assert_eq!(rem, 2);
// check const
let mut x: u64 = 42;
unsafe {
asm!("add {}, {}",
inout(reg) x,
const 1
);
}
assert_eq!(x, 43);
// check const (ATT syntax)
let mut x: u64 = 42;
unsafe {
asm!("add ${}, {}",
const 1,
inout(reg) x,
options(att_syntax)
);
}
assert_eq!(x, 43);
// check sym fn
extern "C" fn foo() -> u64 {
42
}
let x: u64;
unsafe {
asm!("call {}", sym foo, lateout("rax") x);
}
assert_eq!(x, 42);
// check sym fn (ATT syntax)
let x: u64;
unsafe {
asm!("call {}", sym foo, lateout("rax") x, options(att_syntax));
}
assert_eq!(x, 42);
// check sym static
static FOO: u64 = 42;
let x: u64;
unsafe {
asm!("mov {1}, qword ptr [rip + {0}]", sym FOO, lateout(reg) x);
}
assert_eq!(x, 42);
// check sym static (ATT syntax)
let x: u64;
unsafe {
asm!("movq {0}(%rip), {1}", sym FOO, lateout(reg) x, options(att_syntax));
}
assert_eq!(x, 42);
assert_eq!(unsafe { add_asm(40, 2) }, 42);
let array1 = [1u8, 2, 3];
let mut array2 = [0u8, 0, 0];
unsafe {
mem_cpy(array2.as_mut_ptr(), array1.as_ptr(), 3);
}
assert_eq!(array1, array2);
}
#[cfg(not(target_arch = "x86_64"))]
fn asm() {}
fn main() {
asm();
}
|
