// significant bit (in hi) and bit 127 is the lowest (lo&1).
type uint128 struct {
	hi uint64
	lo uint64
}

// mask6 returns a uint128 bitmask with the topmost n bits of a
// 128-bit number.
func mask6(n int) uint128 {
	return uint128{^(^uint64(0) >> n), ^uint64(0) << (128 - n)}
}

// isZero reports whether u == 0.
//

    inlining_test.go:102: not in expected set, but also inlinable: "Addr.MarshalBinary"
    inlining_test.go:102: not in expected set, but also inlinable: "bePutUint64"
    inlining_test.go:102: not in expected set, but also inlinable: "mask6"
    inlining_test.go:102: not in expected set, but also inlinable: "AddrPort.isZero"
    inlining_test.go:102: not in expected set, but also inlinable: "stringsLastIndexByte"

{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"bePutUint64\"\n"}
{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"mask6\"\n"}
{"Action":"output","Test":"TestInlining","Output":"    inlining_test.go:102: not in expected set, but also inlinable: \"AddrPort.isZero\"\n"}

		return ip.addr.xor(p.ip.addr).and(mask6(p.Bits())).isZero()
	}
}

// Overlaps reports whether p and o contain any IP addresses in common.
//
// If p and o are of different address families or either have a zero
// IP, it reports false. Like the Contains method, a prefix with an
// IPv4-mapped IPv6 address is still treated as an IPv6 mask.
func (p Prefix) Overlaps(o Prefix) bool {

		return rune(p0&mask2)<<6 | rune(b1&maskx), 2
	}
	b2 := p[2]
	if b2 < locb || hicb < b2 {
		return RuneError, 1
	}
	if sz <= 3 {
		return rune(p0&mask3)<<12 | rune(b1&maskx)<<6 | rune(b2&maskx), 3
	}
	b3 := p[3]
	if b3 < locb || hicb < b3 {
		return RuneError, 1
	}
	return rune(p0&mask4)<<18 | rune(b1&maskx)<<12 | rune(b2&maskx)<<6 | rune(b3&maskx), 4
}

		if len(s) > 1 && (locb <= s[1] && s[1] <= hicb) {
			r = rune(s[0]&mask2)<<6 | rune(s[1]&maskx)
			pos += 2
			if rune1Max < r {
				return
			}
		}
	case t3 <= s[0] && s[0] < t4:
		// 0800-FFFF three byte sequence
		if len(s) > 2 && (locb <= s[1] && s[1] <= hicb) && (locb <= s[2] && s[2] <= hicb) {
			r = rune(s[0]&mask3)<<12 | rune(s[1]&maskx)<<6 | rune(s[2]&maskx)
			pos += 3

	"math"
	"math/bits"
)

// Mask allows filtering by a bitset mask.
type Mask uint64

const (
	// MaskAll is the mask for all entries.
	MaskAll Mask = math.MaxUint64
)

// MaskFromMaskable extracts mask from an interface.
func MaskFromMaskable(m Maskable) Mask {
	return Mask(m.Mask())
}

// Contains returns whether *all* flags in other is present in t.
func (t Mask) Contains(other Mask) bool {
	return t&other == other

	}

	var mask image.Image
	switch mcm {
	case nil:
		// No-op.
	case color.AlphaModel:
		mask1 := image.NewAlpha(image.Rect(0, 0, srcw, srch))
		for y := 0; y < srch; y++ {
			for x := 0; x < srcw; x++ {
				a := uint8((23*x + 29*y) % 0x100)
				// Glyph masks are typically mostly zero,
				// so we only set a quarter of mask1's pixels.
				if a >= 0xc0 {

		}
		mask &^= 1 << uint64(i)
	}
	*s = mask
	return nil
}

// And performs and operation on all bits in masks
func (s *bitMask) And(masks ...BitMask) {
	for _, m := range masks {
		*s &= *m.(*bitMask)
	}
}

// Or performs or operation on all bits in masks
func (s *bitMask) Or(masks ...BitMask) {
	for _, m := range masks {
		*s |= *m.(*bitMask)
	}
}

		{
			name:   "Mask 01 OR mask 10",
			masks:  [][]int{{0}, {1}},
			orMask: "11",
		},
		{
			name:   "Mask 11 OR mask 11",
			masks:  [][]int{{0, 1}, {0, 1}},
			orMask: "11",
		},
		{
			name:   "Mask 01 OR mask 10 OR mask 11",
			masks:  [][]int{{0}, {1}, {0, 1}},
			orMask: "11",
		},
		{
			name:   "Mask 1000 OR mask 0100 OR mask 0010 OR mask 0001",
			masks:  [][]int{{3}, {2}, {1}, {0}},