// so the n we want is in [index/2, index/2+log₂(index)].
	n = index / 2
	indexN := StoredHashIndex(0, n)
	if indexN > index {
		panic("bad math")
	}
	for {
		// Each new record n adds 1 + trailingZeros(n) hashes.
		x := indexN + 1 + int64(bits.TrailingZeros64(uint64(n+1)))
		if x > index {
			break
		}
		n++
		indexN = x
	}
	// The hash we want was committed with record n,

	// Output:
	// LeadingZeros64(0000000000000000000000000000000000000000000000000000000000000001) = 63
}

func ExampleTrailingZeros8() {
	fmt.Printf("TrailingZeros8(%08b) = %d\n", 14, bits.TrailingZeros8(14))
	// Output:
	// TrailingZeros8(00001110) = 1
}

func ExampleTrailingZeros16() {
	fmt.Printf("TrailingZeros16(%016b) = %d\n", 14, bits.TrailingZeros16(14))
	// Output:

matched. For example, the following test:

  func TZ8(n uint8) int {
  	   // amd64:"BSFQ","ORQ\t\\$256"
  	   return bits.TrailingZeros8(n)
  }

verifies that the code generated for a bits.TrailingZeros8 call on
amd64 contains both a "BSFQ" instruction and an "ORQ $256".

Note how the ORQ regex includes a tab char (\t). In the Go assembly

	// substring ended up at the top of the word.
	// (Knuth, volume 4, section 7.3.1)
	return int(deBruijn64tab[(x&-x)*deBruijn64>>(64-6)])
}

// TrailingZeros8 returns the number of trailing zero bits in x; the result is 8 for x == 0.
func TrailingZeros8(x uint8) int {
	return int(ntz8tab[x])
}

const len8tab = "" +
	"\x00\x01\x02\x02\x03\x03\x03\x03\x04\x04\x04\x04\x04\x04\x04\x04" +

		{"RotateLeft64", Func, 9},
		{"RotateLeft8", Func, 9},
		{"Sub", Func, 12},
		{"Sub32", Func, 12},
		{"Sub64", Func, 12},
		{"TrailingZeros", Func, 9},
		{"TrailingZeros16", Func, 9},
		{"TrailingZeros32", Func, 9},
		{"TrailingZeros64", Func, 9},
		{"TrailingZeros8", Func, 9},
		{"UintSize", Const, 9},
	},
	"math/cmplx": {
		{"Abs", Func, 0},
		{"Acos", Func, 0},
		{"Acosh", Func, 0},

			}
		}
		b := *(addb(bv.bytedata, i/8))
		for b != 0 {
			j := uintptr(sys.TrailingZeros8(b))
			b &= b - 1
			pp := (*uintptr)(add(scanp, (i+j)*goarch.PtrSize))
		retry:
			p := *pp
			if f.valid() && 0 < p && p < minLegalPointer && debug.invalidptr != 0 {

		},
		sys.MIPS)
	addF("math/bits", "TrailingZeros8",
		func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value {
			return s.newValue1(ssa.OpCtz8, types.Types[types.TINT], args[0])
		},
		sys.AMD64, sys.I386, sys.ARM, sys.ARM64, sys.Wasm)
	addF("math/bits", "TrailingZeros8",
		func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value {

func ntz32(x int32) int { return bits.TrailingZeros32(uint32(x)) }
func ntz16(x int16) int { return bits.TrailingZeros16(uint16(x)) }
func ntz8(x int8) int   { return bits.TrailingZeros8(uint8(x)) }

func oneBit(x int64) bool   { return x&(x-1) == 0 && x != 0 }
func oneBit8(x int8) bool   { return x&(x-1) == 0 && x != 0 }
func oneBit16(x int16) bool { return x&(x-1) == 0 && x != 0 }