}

// TrailingZeros64 returns the number of trailing zero bits in x; the result is 64 for x == 0.
func TrailingZeros64(x uint64) int {
	if x == 0 {
		return 64
	}
	// If popcount is fast, replace code below with return popcount(^x & (x - 1)).
	//
	// x & -x leaves only the right-most bit set in the word. Let k be the
	// index of that bit. Since only a single bit is set, the value is two

	// arm64:`EON\t`,-`EOR`,-`MVN`
	a[1] = ^(y ^ z)

	// arm64:`EON\t`,-`XOR`
	a[2] = x ^ ^z

	// arm64:`EON\t`,-`EOR`,-`MVN`
	return n ^ (m ^ 0xffffffffffffffff)
}

func op_orn(x, y uint32) uint32 {
	// arm64:`ORN\t`,-`ORR`
	return x | ^y
}

// check bitsets
func bitSetPowerOf2Test(x int) bool {
	// amd64:"BTL\t[$]3"
	return x&8 == 8
}