}

// check 16-bit shift masking
func mask16(x uint16) uint16 {
	return (x << 14) >> 14 // arm64:"AND\t[$]3, R[0-9]+",-"LSR",-"LSL"
}

// check 8-bit shift masking
func mask8(x uint8) uint8 {
	return (x << 7) >> 7 // arm64:"AND\t[$]1, R[0-9]+",-"LSR",-"LSL"
}

func maskshift(x uint64) uint64 {
	// arm64:"AND\t[$]4095, R[0-9]+",-"LSL",-"LSR",-"UBFIZ",-"UBFX"

		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}},

		r |= Less
	}
	return r
}

func (c CCMask) String() string {
	switch c {
	// 0-bit mask
	case Never:
		return "Never"

	// 1-bit masks
	case Equal:
		return "Equal"
	case Less:
		return "Less"
	case Greater:
		return "Greater"
	case Unordered:
		return "Unordered"

	// 2-bit masks
	case EqualOrUnordered:
		return "EqualOrUnordered"
	case LessOrEqual:
		return "LessOrEqual"

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package main

func mask1(a, b uint64) uint64 {
	op1 := int32(a)
	op2 := int32(b)
	return uint64(uint32(op1 / op2))
}

var mask2 = mask1

func main() {
	res1 := mask1(0x1, 0xfffffffeffffffff)
	res2 := mask2(0x1, 0xfffffffeffffffff)
	if res1 != 0xffffffff {
		println("got", res1, "want", 0xffffffff)
		panic("FAIL")
	}

		// may be larger than we expect.
		return
	}
	t.Errorf("bad GC program for %v:\nwant %+v\ngot  %+v", name, mask0, mask)
}

func trimDead(mask []byte) []byte {
	for len(mask) > 0 && mask[len(mask)-1] == typeScalar {
		mask = mask[:len(mask)-1]
	}
	return mask
}

var infoPtr = []byte{typePointer}

type Ptr struct {
	*byte
}