5 #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
6 unsafe fn next_power_of_2(n: u32) -> u32 {
8 asm!("dec $0" : "+rm"(tmp) :: "cc");
15 : "+&rm"(tmp), "+{ecx}"(shift) : "r"(tmp) : "cc"
18 asm!("inc $0" : "+rm"(tmp) :: "cc");
22 #[cfg(any(target_arch = "x86", target_arch = "x86_64"))]
25 assert_eq!(64, next_power_of_2(37));
26 assert_eq!(2147483648, next_power_of_2(2147483647));
32 // Treat the output as initialization.
37 : "=r"(x), "+r"(y) : "i"(3_usize), "ir"(7_usize) : "cc"
47 // Assignment to mutable.
49 // Forbids the use of a single register by both operands.
50 asm!("shr $$2, $1; add $1, $0" : "+&r"(x) : "r"(x) : "cc");
55 #[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]