package math

// Ldexp is the inverse of [Frexp].
// It returns frac × 2**exp.
//
// Special cases are:
//
//	Ldexp(±0, exp) = ±0
//	Ldexp(±Inf, exp) = ±Inf
//	Ldexp(NaN, exp) = NaN
func Ldexp(frac float64, exp int) float64 {
	if haveArchLdexp {
		return archLdexp(frac, exp)
	}
	return ldexp(frac, exp)
}

func ldexp(frac float64, exp int) float64 {
	// special cases
	switch {

	)

	r := hi - lo
	t := r * r
	c := r - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))))
	y := 1 - ((lo - (r*c)/(2-c)) - hi)
	// TODO(rsc): make sure Ldexp can handle boundary k
	return Ldexp(y, k)

			// on at least one more iteration, ae += xe is a lower bound on ae
			// the lower bound on ae exceeds the size of a float64 exp
			// so the final call to Ldexp will produce under/overflow (0/Inf)
			ae += xe
			break
		}
		if i&1 == 1 {
			a1 *= x1
			ae += xe
		}
		x1 *= x1
		xe <<= 1
		if x1 < .5 {
			x1 += x1
			xe--
		}
	}

	// arm64:"CSEL\tNE"
	// ppc64x:"ISEL\t[$]2"
	// wasm:"Select"
	return a
}

//go:noinline
func frexp(f float64) (frac float64, exp int) {
	return 1.0, 4
}

//go:noinline
func ldexp(frac float64, exp int) float64 {
	return 1.0
}

// Generate a CMOV with a floating comparison and integer move.
func cmovfloatint2(x, y float64) float64 {
	yfr, yexp := 4.0, 5

	r := x
	for r >= y {

}

func TestLdexp(t *testing.T) {
	for i := 0; i < len(vf); i++ {
		if f := Ldexp(frexp[i].f, frexp[i].i); !veryclose(vf[i], f) {
			t.Errorf("Ldexp(%g, %d) = %g, want %g", frexp[i].f, frexp[i].i, f, vf[i])
		}
	}
	for i := 0; i < len(vffrexpSC); i++ {
		if f := Ldexp(frexpSC[i].f, frexpSC[i].i); !alike(vffrexpSC[i], f) {
			t.Errorf("Ldexp(%g, %d) = %g, want %g", frexpSC[i].f, frexpSC[i].i, f, vffrexpSC[i])
		}
	}

				// Complete rollover 11...1 => 100...0, so shift is safe
				mantissa >>= 1
				exp++
			}
		}
	}
	mantissa >>= 1 // discard rounding bit.  Mantissa now scaled by 1<<Msize1.

	f = float32(math.Ldexp(float64(mantissa), exp-Msize1))
	if math.IsInf(float64(f), 0) {
		exact = false
	}
	return
}

// quotToFloat64 returns the non-negative float64 value
// nearest to the quotient a/b, using round-to-even in

		}
		m, err := strconv.Atoi(str[p+1:])
		if err != nil {
			// Put full string into error.
			if e, ok := err.(*strconv.NumError); ok {
				e.Num = str
			}
			s.error(err)
		}
		return math.Ldexp(f, m)
	}
	f, err := strconv.ParseFloat(str, n)
	if err != nil {
		s.error(err)
	}
	return f
}

// scanComplex converts the next token to a complex128 value.

	"LDADDALH",
	"LDADDALW",
	"LDADDAW",
	"LDADDB",
	"LDADDD",
	"LDADDH",
	"LDADDLB",
	"LDADDLD",
	"LDADDLH",
	"LDADDLW",
	"LDADDW",
	"LDAR",
	"LDARB",
	"LDARH",
	"LDARW",
	"LDAXP",
	"LDAXPW",
	"LDAXR",
	"LDAXRB",
	"LDAXRH",
	"LDAXRW",
	"LDCLRAB",
	"LDCLRAD",
	"LDCLRAH",
	"LDCLRALB",
	"LDCLRALD",
	"LDCLRALH",
	"LDCLRALW",
	"LDCLRAW",
	"LDCLRB",

	type delMarkerExpiration DelMarkerExpiration
	var dexp delMarkerExpiration
	err := dec.DecodeElement(&dexp, &start)
	if err != nil {
		return err
	}

	if dexp.Days <= 0 {
		return errInvalidDaysDelMarkerExpiration
	}

	*de = DelMarkerExpiration(dexp)
	return nil
}

// MarshalXML encodes a DelMarkerExpiration value into an XML element

			err: errInvalidDaysDelMarkerExpiration,
		},
	}

	for i, test := range tests {
		t.Run(fmt.Sprintf("TestDelMarker-%d", i), func(t *testing.T) {
			var dexp DelMarkerExpiration
			var fail bool
			err := xml.Unmarshal([]byte(test.xml), &dexp)
			if test.err == nil {
				if err != nil {
					fail = true
				}
			} else {
				if err == nil {
					fail = true
				}
				if test.err.Error() != err.Error() {