Toniolo and Linder, Equation (7)

Percentage Accurate: 33.9% → 85.2%
Time: 23.1s
Alternatives: 11
Speedup: 225.0×

Specification

?
\[\begin{array}{l} \\ \frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \end{array} \]
(FPCore (x l t)
 :precision binary64
 (/
  (* (sqrt 2.0) t)
  (sqrt (- (* (/ (+ x 1.0) (- x 1.0)) (+ (* l l) (* 2.0 (* t t)))) (* l l)))))
double code(double x, double l, double t) {
	return (sqrt(2.0) * t) / sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
}
real(8) function code(x, l, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: l
    real(8), intent (in) :: t
    code = (sqrt(2.0d0) * t) / sqrt(((((x + 1.0d0) / (x - 1.0d0)) * ((l * l) + (2.0d0 * (t * t)))) - (l * l)))
end function
public static double code(double x, double l, double t) {
	return (Math.sqrt(2.0) * t) / Math.sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
}
def code(x, l, t):
	return (math.sqrt(2.0) * t) / math.sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)))
function code(x, l, t)
	return Float64(Float64(sqrt(2.0) * t) / sqrt(Float64(Float64(Float64(Float64(x + 1.0) / Float64(x - 1.0)) * Float64(Float64(l * l) + Float64(2.0 * Float64(t * t)))) - Float64(l * l))))
end
function tmp = code(x, l, t)
	tmp = (sqrt(2.0) * t) / sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
end
code[x_, l_, t_] := N[(N[(N[Sqrt[2.0], $MachinePrecision] * t), $MachinePrecision] / N[Sqrt[N[(N[(N[(N[(x + 1.0), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision] * N[(N[(l * l), $MachinePrecision] + N[(2.0 * N[(t * t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(l * l), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 11 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 33.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \end{array} \]
(FPCore (x l t)
 :precision binary64
 (/
  (* (sqrt 2.0) t)
  (sqrt (- (* (/ (+ x 1.0) (- x 1.0)) (+ (* l l) (* 2.0 (* t t)))) (* l l)))))
double code(double x, double l, double t) {
	return (sqrt(2.0) * t) / sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
}
real(8) function code(x, l, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: l
    real(8), intent (in) :: t
    code = (sqrt(2.0d0) * t) / sqrt(((((x + 1.0d0) / (x - 1.0d0)) * ((l * l) + (2.0d0 * (t * t)))) - (l * l)))
end function
public static double code(double x, double l, double t) {
	return (Math.sqrt(2.0) * t) / Math.sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
}
def code(x, l, t):
	return (math.sqrt(2.0) * t) / math.sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)))
function code(x, l, t)
	return Float64(Float64(sqrt(2.0) * t) / sqrt(Float64(Float64(Float64(Float64(x + 1.0) / Float64(x - 1.0)) * Float64(Float64(l * l) + Float64(2.0 * Float64(t * t)))) - Float64(l * l))))
end
function tmp = code(x, l, t)
	tmp = (sqrt(2.0) * t) / sqrt(((((x + 1.0) / (x - 1.0)) * ((l * l) + (2.0 * (t * t)))) - (l * l)));
end
code[x_, l_, t_] := N[(N[(N[Sqrt[2.0], $MachinePrecision] * t), $MachinePrecision] / N[Sqrt[N[(N[(N[(N[(x + 1.0), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision] * N[(N[(l * l), $MachinePrecision] + N[(2.0 * N[(t * t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(l * l), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}
\end{array}

Alternative 1: 85.2% accurate, 0.2× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ \begin{array}{l} t_2 := 2 \cdot {t_m}^{2}\\ t_3 := t_2 + {l_m}^{2}\\ t_4 := t_3 + t_3\\ t_s \cdot \begin{array}{l} \mathbf{if}\;t_m \leq 9.8 \cdot 10^{-254}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t_m}{l_m \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\ \mathbf{elif}\;t_m \leq 4 \cdot 10^{-169}:\\ \;\;\;\;t_m \cdot \frac{\sqrt{2}}{0.5 \cdot \frac{t_4}{t_m \cdot \left(\sqrt{2} \cdot x\right)} + t_m \cdot \sqrt{2}}\\ \mathbf{elif}\;t_m \leq 6.4 \cdot 10^{+84}:\\ \;\;\;\;t_m \cdot \frac{\sqrt{2}}{\sqrt{\left(\frac{t_4}{{x}^{2}} + \left(2 \cdot \frac{{t_m}^{2}}{x} + \left(t_2 + \frac{{l_m}^{2}}{x}\right)\right)\right) + \frac{t_3}{x}}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \end{array} \end{array} \end{array} \]
l_m = (fabs.f64 l)
t_m = (fabs.f64 t)
t_s = (copysign.f64 1 t)
(FPCore (t_s x l_m t_m)
 :precision binary64
 (let* ((t_2 (* 2.0 (pow t_m 2.0)))
        (t_3 (+ t_2 (pow l_m 2.0)))
        (t_4 (+ t_3 t_3)))
   (*
    t_s
    (if (<= t_m 9.8e-254)
      (* (sqrt 2.0) (/ t_m (* l_m (sqrt (+ (/ 1.0 (+ -1.0 x)) (/ 1.0 x))))))
      (if (<= t_m 4e-169)
        (*
         t_m
         (/
          (sqrt 2.0)
          (+ (* 0.5 (/ t_4 (* t_m (* (sqrt 2.0) x)))) (* t_m (sqrt 2.0)))))
        (if (<= t_m 6.4e+84)
          (*
           t_m
           (/
            (sqrt 2.0)
            (sqrt
             (+
              (+
               (/ t_4 (pow x 2.0))
               (+ (* 2.0 (/ (pow t_m 2.0) x)) (+ t_2 (/ (pow l_m 2.0) x))))
              (/ t_3 x)))))
          (sqrt (/ (+ -1.0 x) (+ 1.0 x)))))))))
l_m = fabs(l);
t_m = fabs(t);
t_s = copysign(1.0, t);
double code(double t_s, double x, double l_m, double t_m) {
	double t_2 = 2.0 * pow(t_m, 2.0);
	double t_3 = t_2 + pow(l_m, 2.0);
	double t_4 = t_3 + t_3;
	double tmp;
	if (t_m <= 9.8e-254) {
		tmp = sqrt(2.0) * (t_m / (l_m * sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	} else if (t_m <= 4e-169) {
		tmp = t_m * (sqrt(2.0) / ((0.5 * (t_4 / (t_m * (sqrt(2.0) * x)))) + (t_m * sqrt(2.0))));
	} else if (t_m <= 6.4e+84) {
		tmp = t_m * (sqrt(2.0) / sqrt((((t_4 / pow(x, 2.0)) + ((2.0 * (pow(t_m, 2.0) / x)) + (t_2 + (pow(l_m, 2.0) / x)))) + (t_3 / x))));
	} else {
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	}
	return t_s * tmp;
}
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0d0, t)
real(8) function code(t_s, x, l_m, t_m)
    real(8), intent (in) :: t_s
    real(8), intent (in) :: x
    real(8), intent (in) :: l_m
    real(8), intent (in) :: t_m
    real(8) :: t_2
    real(8) :: t_3
    real(8) :: t_4
    real(8) :: tmp
    t_2 = 2.0d0 * (t_m ** 2.0d0)
    t_3 = t_2 + (l_m ** 2.0d0)
    t_4 = t_3 + t_3
    if (t_m <= 9.8d-254) then
        tmp = sqrt(2.0d0) * (t_m / (l_m * sqrt(((1.0d0 / ((-1.0d0) + x)) + (1.0d0 / x)))))
    else if (t_m <= 4d-169) then
        tmp = t_m * (sqrt(2.0d0) / ((0.5d0 * (t_4 / (t_m * (sqrt(2.0d0) * x)))) + (t_m * sqrt(2.0d0))))
    else if (t_m <= 6.4d+84) then
        tmp = t_m * (sqrt(2.0d0) / sqrt((((t_4 / (x ** 2.0d0)) + ((2.0d0 * ((t_m ** 2.0d0) / x)) + (t_2 + ((l_m ** 2.0d0) / x)))) + (t_3 / x))))
    else
        tmp = sqrt((((-1.0d0) + x) / (1.0d0 + x)))
    end if
    code = t_s * tmp
end function
l_m = Math.abs(l);
t_m = Math.abs(t);
t_s = Math.copySign(1.0, t);
public static double code(double t_s, double x, double l_m, double t_m) {
	double t_2 = 2.0 * Math.pow(t_m, 2.0);
	double t_3 = t_2 + Math.pow(l_m, 2.0);
	double t_4 = t_3 + t_3;
	double tmp;
	if (t_m <= 9.8e-254) {
		tmp = Math.sqrt(2.0) * (t_m / (l_m * Math.sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	} else if (t_m <= 4e-169) {
		tmp = t_m * (Math.sqrt(2.0) / ((0.5 * (t_4 / (t_m * (Math.sqrt(2.0) * x)))) + (t_m * Math.sqrt(2.0))));
	} else if (t_m <= 6.4e+84) {
		tmp = t_m * (Math.sqrt(2.0) / Math.sqrt((((t_4 / Math.pow(x, 2.0)) + ((2.0 * (Math.pow(t_m, 2.0) / x)) + (t_2 + (Math.pow(l_m, 2.0) / x)))) + (t_3 / x))));
	} else {
		tmp = Math.sqrt(((-1.0 + x) / (1.0 + x)));
	}
	return t_s * tmp;
}
l_m = math.fabs(l)
t_m = math.fabs(t)
t_s = math.copysign(1.0, t)
def code(t_s, x, l_m, t_m):
	t_2 = 2.0 * math.pow(t_m, 2.0)
	t_3 = t_2 + math.pow(l_m, 2.0)
	t_4 = t_3 + t_3
	tmp = 0
	if t_m <= 9.8e-254:
		tmp = math.sqrt(2.0) * (t_m / (l_m * math.sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))))
	elif t_m <= 4e-169:
		tmp = t_m * (math.sqrt(2.0) / ((0.5 * (t_4 / (t_m * (math.sqrt(2.0) * x)))) + (t_m * math.sqrt(2.0))))
	elif t_m <= 6.4e+84:
		tmp = t_m * (math.sqrt(2.0) / math.sqrt((((t_4 / math.pow(x, 2.0)) + ((2.0 * (math.pow(t_m, 2.0) / x)) + (t_2 + (math.pow(l_m, 2.0) / x)))) + (t_3 / x))))
	else:
		tmp = math.sqrt(((-1.0 + x) / (1.0 + x)))
	return t_s * tmp
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0, t)
function code(t_s, x, l_m, t_m)
	t_2 = Float64(2.0 * (t_m ^ 2.0))
	t_3 = Float64(t_2 + (l_m ^ 2.0))
	t_4 = Float64(t_3 + t_3)
	tmp = 0.0
	if (t_m <= 9.8e-254)
		tmp = Float64(sqrt(2.0) * Float64(t_m / Float64(l_m * sqrt(Float64(Float64(1.0 / Float64(-1.0 + x)) + Float64(1.0 / x))))));
	elseif (t_m <= 4e-169)
		tmp = Float64(t_m * Float64(sqrt(2.0) / Float64(Float64(0.5 * Float64(t_4 / Float64(t_m * Float64(sqrt(2.0) * x)))) + Float64(t_m * sqrt(2.0)))));
	elseif (t_m <= 6.4e+84)
		tmp = Float64(t_m * Float64(sqrt(2.0) / sqrt(Float64(Float64(Float64(t_4 / (x ^ 2.0)) + Float64(Float64(2.0 * Float64((t_m ^ 2.0) / x)) + Float64(t_2 + Float64((l_m ^ 2.0) / x)))) + Float64(t_3 / x)))));
	else
		tmp = sqrt(Float64(Float64(-1.0 + x) / Float64(1.0 + x)));
	end
	return Float64(t_s * tmp)
end
l_m = abs(l);
t_m = abs(t);
t_s = sign(t) * abs(1.0);
function tmp_2 = code(t_s, x, l_m, t_m)
	t_2 = 2.0 * (t_m ^ 2.0);
	t_3 = t_2 + (l_m ^ 2.0);
	t_4 = t_3 + t_3;
	tmp = 0.0;
	if (t_m <= 9.8e-254)
		tmp = sqrt(2.0) * (t_m / (l_m * sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	elseif (t_m <= 4e-169)
		tmp = t_m * (sqrt(2.0) / ((0.5 * (t_4 / (t_m * (sqrt(2.0) * x)))) + (t_m * sqrt(2.0))));
	elseif (t_m <= 6.4e+84)
		tmp = t_m * (sqrt(2.0) / sqrt((((t_4 / (x ^ 2.0)) + ((2.0 * ((t_m ^ 2.0) / x)) + (t_2 + ((l_m ^ 2.0) / x)))) + (t_3 / x))));
	else
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	end
	tmp_2 = t_s * tmp;
end
l_m = N[Abs[l], $MachinePrecision]
t_m = N[Abs[t], $MachinePrecision]
t_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[t$95$s_, x_, l$95$m_, t$95$m_] := Block[{t$95$2 = N[(2.0 * N[Power[t$95$m, 2.0], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(t$95$2 + N[Power[l$95$m, 2.0], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(t$95$3 + t$95$3), $MachinePrecision]}, N[(t$95$s * If[LessEqual[t$95$m, 9.8e-254], N[(N[Sqrt[2.0], $MachinePrecision] * N[(t$95$m / N[(l$95$m * N[Sqrt[N[(N[(1.0 / N[(-1.0 + x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$m, 4e-169], N[(t$95$m * N[(N[Sqrt[2.0], $MachinePrecision] / N[(N[(0.5 * N[(t$95$4 / N[(t$95$m * N[(N[Sqrt[2.0], $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$m * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$m, 6.4e+84], N[(t$95$m * N[(N[Sqrt[2.0], $MachinePrecision] / N[Sqrt[N[(N[(N[(t$95$4 / N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision] + N[(N[(2.0 * N[(N[Power[t$95$m, 2.0], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] + N[(t$95$2 + N[(N[Power[l$95$m, 2.0], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$3 / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[(-1.0 + x), $MachinePrecision] / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]]]), $MachinePrecision]]]]
\begin{array}{l}
l_m = \left|\ell\right|
\\
t_m = \left|t\right|
\\
t_s = \mathsf{copysign}\left(1, t\right)

\\
\begin{array}{l}
t_2 := 2 \cdot {t_m}^{2}\\
t_3 := t_2 + {l_m}^{2}\\
t_4 := t_3 + t_3\\
t_s \cdot \begin{array}{l}
\mathbf{if}\;t_m \leq 9.8 \cdot 10^{-254}:\\
\;\;\;\;\sqrt{2} \cdot \frac{t_m}{l_m \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\

\mathbf{elif}\;t_m \leq 4 \cdot 10^{-169}:\\
\;\;\;\;t_m \cdot \frac{\sqrt{2}}{0.5 \cdot \frac{t_4}{t_m \cdot \left(\sqrt{2} \cdot x\right)} + t_m \cdot \sqrt{2}}\\

\mathbf{elif}\;t_m \leq 6.4 \cdot 10^{+84}:\\
\;\;\;\;t_m \cdot \frac{\sqrt{2}}{\sqrt{\left(\frac{t_4}{{x}^{2}} + \left(2 \cdot \frac{{t_m}^{2}}{x} + \left(t_2 + \frac{{l_m}^{2}}{x}\right)\right)\right) + \frac{t_3}{x}}}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\


\end{array}
\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if t < 9.79999999999999959e-254

    1. Initial program 28.2%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified28.1%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(\frac{x + 1}{x + -1}, \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right), \ell \cdot \left(-\ell\right)\right)}}} \]
    3. Taylor expanded in l around inf 2.7%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{\ell \cdot \sqrt{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}}} \]
    4. Step-by-step derivation
      1. associate--l+9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\color{blue}{\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)}}} \]
      2. sub-neg9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      3. metadata-eval9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      4. +-commutative9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      5. sub-neg9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)}} \]
      6. metadata-eval9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)}} \]
      7. +-commutative9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)}} \]
    5. Simplified9.8%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)}}} \]
    6. Taylor expanded in x around inf 20.9%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \color{blue}{\frac{1}{x}}}} \]

    if 9.79999999999999959e-254 < t < 4.00000000000000008e-169

    1. Initial program 2.6%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified2.6%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right) - \ell \cdot \ell}} \cdot t} \]
    3. Taylor expanded in x around inf 67.3%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{0.5 \cdot \frac{\left(2 \cdot {t}^{2} + {\ell}^{2}\right) - -1 \cdot \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)} + t \cdot \sqrt{2}}} \cdot t \]

    if 4.00000000000000008e-169 < t < 6.4000000000000002e84

    1. Initial program 45.6%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified45.8%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right) - \ell \cdot \ell}} \cdot t} \]
    3. Taylor expanded in x around -inf 78.4%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{\left(-1 \cdot \frac{-1 \cdot \left(2 \cdot {t}^{2} + {\ell}^{2}\right) - \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{{x}^{2}} + \left(2 \cdot \frac{{t}^{2}}{x} + \left(2 \cdot {t}^{2} + \frac{{\ell}^{2}}{x}\right)\right)\right) - -1 \cdot \frac{2 \cdot {t}^{2} + {\ell}^{2}}{x}}}} \cdot t \]

    if 6.4000000000000002e84 < t

    1. Initial program 23.3%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified23.3%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 100.0%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified100.0%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Step-by-step derivation
      1. sqrt-unprod100.0%

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      2. sqrt-undiv100.0%

        \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      3. +-commutative100.0%

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{\color{blue}{x + -1}}}} \]
    7. Applied egg-rr100.0%

      \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{x + -1}}}} \]
    8. Step-by-step derivation
      1. associate-/r*100.0%

        \[\leadsto \sqrt{\color{blue}{\frac{\frac{2}{2}}{\frac{x + 1}{x + -1}}}} \]
      2. metadata-eval100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{1}}{\frac{x + 1}{x + -1}}} \]
      3. +-commutative100.0%

        \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    9. Simplified100.0%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{x + 1}{-1 + x}}}} \]
    10. Step-by-step derivation
      1. expm1-log1p-u100.0%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)\right)}} \]
      2. expm1-udef100.0%

        \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)} - 1}} \]
      3. associate-/r/100.0%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\color{blue}{\frac{1}{x + 1} \cdot \left(-1 + x\right)}\right)} - 1} \]
      4. +-commutative100.0%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{1 + x}} \cdot \left(-1 + x\right)\right)} - 1} \]
      5. +-commutative100.0%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \color{blue}{\left(x + -1\right)}\right)} - 1} \]
    11. Applied egg-rr100.0%

      \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)} - 1}} \]
    12. Step-by-step derivation
      1. expm1-def100.0%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)\right)}} \]
      2. expm1-log1p99.5%

        \[\leadsto \sqrt{\color{blue}{\frac{1}{1 + x} \cdot \left(x + -1\right)}} \]
      3. metadata-eval99.5%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \left(x + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg99.5%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \color{blue}{\left(x - 1\right)}} \]
      5. associate-*l/100.0%

        \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot \left(x - 1\right)}{1 + x}}} \]
      6. *-lft-identity100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{x - 1}}{1 + x}} \]
      7. sub-neg100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{x + \left(-1\right)}}{1 + x}} \]
      8. metadata-eval100.0%

        \[\leadsto \sqrt{\frac{x + \color{blue}{-1}}{1 + x}} \]
      9. +-commutative100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{-1 + x}}{1 + x}} \]
      10. +-commutative100.0%

        \[\leadsto \sqrt{\frac{-1 + x}{\color{blue}{x + 1}}} \]
    13. Simplified100.0%

      \[\leadsto \sqrt{\color{blue}{\frac{-1 + x}{x + 1}}} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification52.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 9.8 \cdot 10^{-254}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\ \mathbf{elif}\;t \leq 4 \cdot 10^{-169}:\\ \;\;\;\;t \cdot \frac{\sqrt{2}}{0.5 \cdot \frac{\left(2 \cdot {t}^{2} + {\ell}^{2}\right) + \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{t \cdot \left(\sqrt{2} \cdot x\right)} + t \cdot \sqrt{2}}\\ \mathbf{elif}\;t \leq 6.4 \cdot 10^{+84}:\\ \;\;\;\;t \cdot \frac{\sqrt{2}}{\sqrt{\left(\frac{\left(2 \cdot {t}^{2} + {\ell}^{2}\right) + \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{{x}^{2}} + \left(2 \cdot \frac{{t}^{2}}{x} + \left(2 \cdot {t}^{2} + \frac{{\ell}^{2}}{x}\right)\right)\right) + \frac{2 \cdot {t}^{2} + {\ell}^{2}}{x}}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \end{array} \]

Alternative 2: 83.7% accurate, 0.3× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ \begin{array}{l} t_2 := 2 \cdot {t_m}^{2}\\ t_s \cdot \begin{array}{l} \mathbf{if}\;t_m \leq 1.6 \cdot 10^{-247}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t_m}{l_m \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\ \mathbf{elif}\;t_m \leq 2.35 \cdot 10^{-166}:\\ \;\;\;\;1\\ \mathbf{elif}\;t_m \leq 3 \cdot 10^{+84}:\\ \;\;\;\;t_m \cdot \frac{\sqrt{2}}{\sqrt{\left(2 \cdot \frac{{t_m}^{2}}{x} + \left(t_2 + \frac{{l_m}^{2}}{x}\right)\right) + \frac{t_2 + {l_m}^{2}}{x}}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \end{array} \end{array} \end{array} \]
l_m = (fabs.f64 l)
t_m = (fabs.f64 t)
t_s = (copysign.f64 1 t)
(FPCore (t_s x l_m t_m)
 :precision binary64
 (let* ((t_2 (* 2.0 (pow t_m 2.0))))
   (*
    t_s
    (if (<= t_m 1.6e-247)
      (* (sqrt 2.0) (/ t_m (* l_m (sqrt (+ (/ 1.0 (+ -1.0 x)) (/ 1.0 x))))))
      (if (<= t_m 2.35e-166)
        1.0
        (if (<= t_m 3e+84)
          (*
           t_m
           (/
            (sqrt 2.0)
            (sqrt
             (+
              (+ (* 2.0 (/ (pow t_m 2.0) x)) (+ t_2 (/ (pow l_m 2.0) x)))
              (/ (+ t_2 (pow l_m 2.0)) x)))))
          (sqrt (/ (+ -1.0 x) (+ 1.0 x)))))))))
l_m = fabs(l);
t_m = fabs(t);
t_s = copysign(1.0, t);
double code(double t_s, double x, double l_m, double t_m) {
	double t_2 = 2.0 * pow(t_m, 2.0);
	double tmp;
	if (t_m <= 1.6e-247) {
		tmp = sqrt(2.0) * (t_m / (l_m * sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	} else if (t_m <= 2.35e-166) {
		tmp = 1.0;
	} else if (t_m <= 3e+84) {
		tmp = t_m * (sqrt(2.0) / sqrt((((2.0 * (pow(t_m, 2.0) / x)) + (t_2 + (pow(l_m, 2.0) / x))) + ((t_2 + pow(l_m, 2.0)) / x))));
	} else {
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	}
	return t_s * tmp;
}
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0d0, t)
real(8) function code(t_s, x, l_m, t_m)
    real(8), intent (in) :: t_s
    real(8), intent (in) :: x
    real(8), intent (in) :: l_m
    real(8), intent (in) :: t_m
    real(8) :: t_2
    real(8) :: tmp
    t_2 = 2.0d0 * (t_m ** 2.0d0)
    if (t_m <= 1.6d-247) then
        tmp = sqrt(2.0d0) * (t_m / (l_m * sqrt(((1.0d0 / ((-1.0d0) + x)) + (1.0d0 / x)))))
    else if (t_m <= 2.35d-166) then
        tmp = 1.0d0
    else if (t_m <= 3d+84) then
        tmp = t_m * (sqrt(2.0d0) / sqrt((((2.0d0 * ((t_m ** 2.0d0) / x)) + (t_2 + ((l_m ** 2.0d0) / x))) + ((t_2 + (l_m ** 2.0d0)) / x))))
    else
        tmp = sqrt((((-1.0d0) + x) / (1.0d0 + x)))
    end if
    code = t_s * tmp
end function
l_m = Math.abs(l);
t_m = Math.abs(t);
t_s = Math.copySign(1.0, t);
public static double code(double t_s, double x, double l_m, double t_m) {
	double t_2 = 2.0 * Math.pow(t_m, 2.0);
	double tmp;
	if (t_m <= 1.6e-247) {
		tmp = Math.sqrt(2.0) * (t_m / (l_m * Math.sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	} else if (t_m <= 2.35e-166) {
		tmp = 1.0;
	} else if (t_m <= 3e+84) {
		tmp = t_m * (Math.sqrt(2.0) / Math.sqrt((((2.0 * (Math.pow(t_m, 2.0) / x)) + (t_2 + (Math.pow(l_m, 2.0) / x))) + ((t_2 + Math.pow(l_m, 2.0)) / x))));
	} else {
		tmp = Math.sqrt(((-1.0 + x) / (1.0 + x)));
	}
	return t_s * tmp;
}
l_m = math.fabs(l)
t_m = math.fabs(t)
t_s = math.copysign(1.0, t)
def code(t_s, x, l_m, t_m):
	t_2 = 2.0 * math.pow(t_m, 2.0)
	tmp = 0
	if t_m <= 1.6e-247:
		tmp = math.sqrt(2.0) * (t_m / (l_m * math.sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))))
	elif t_m <= 2.35e-166:
		tmp = 1.0
	elif t_m <= 3e+84:
		tmp = t_m * (math.sqrt(2.0) / math.sqrt((((2.0 * (math.pow(t_m, 2.0) / x)) + (t_2 + (math.pow(l_m, 2.0) / x))) + ((t_2 + math.pow(l_m, 2.0)) / x))))
	else:
		tmp = math.sqrt(((-1.0 + x) / (1.0 + x)))
	return t_s * tmp
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0, t)
function code(t_s, x, l_m, t_m)
	t_2 = Float64(2.0 * (t_m ^ 2.0))
	tmp = 0.0
	if (t_m <= 1.6e-247)
		tmp = Float64(sqrt(2.0) * Float64(t_m / Float64(l_m * sqrt(Float64(Float64(1.0 / Float64(-1.0 + x)) + Float64(1.0 / x))))));
	elseif (t_m <= 2.35e-166)
		tmp = 1.0;
	elseif (t_m <= 3e+84)
		tmp = Float64(t_m * Float64(sqrt(2.0) / sqrt(Float64(Float64(Float64(2.0 * Float64((t_m ^ 2.0) / x)) + Float64(t_2 + Float64((l_m ^ 2.0) / x))) + Float64(Float64(t_2 + (l_m ^ 2.0)) / x)))));
	else
		tmp = sqrt(Float64(Float64(-1.0 + x) / Float64(1.0 + x)));
	end
	return Float64(t_s * tmp)
end
l_m = abs(l);
t_m = abs(t);
t_s = sign(t) * abs(1.0);
function tmp_2 = code(t_s, x, l_m, t_m)
	t_2 = 2.0 * (t_m ^ 2.0);
	tmp = 0.0;
	if (t_m <= 1.6e-247)
		tmp = sqrt(2.0) * (t_m / (l_m * sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	elseif (t_m <= 2.35e-166)
		tmp = 1.0;
	elseif (t_m <= 3e+84)
		tmp = t_m * (sqrt(2.0) / sqrt((((2.0 * ((t_m ^ 2.0) / x)) + (t_2 + ((l_m ^ 2.0) / x))) + ((t_2 + (l_m ^ 2.0)) / x))));
	else
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	end
	tmp_2 = t_s * tmp;
end
l_m = N[Abs[l], $MachinePrecision]
t_m = N[Abs[t], $MachinePrecision]
t_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[t$95$s_, x_, l$95$m_, t$95$m_] := Block[{t$95$2 = N[(2.0 * N[Power[t$95$m, 2.0], $MachinePrecision]), $MachinePrecision]}, N[(t$95$s * If[LessEqual[t$95$m, 1.6e-247], N[(N[Sqrt[2.0], $MachinePrecision] * N[(t$95$m / N[(l$95$m * N[Sqrt[N[(N[(1.0 / N[(-1.0 + x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$m, 2.35e-166], 1.0, If[LessEqual[t$95$m, 3e+84], N[(t$95$m * N[(N[Sqrt[2.0], $MachinePrecision] / N[Sqrt[N[(N[(N[(2.0 * N[(N[Power[t$95$m, 2.0], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] + N[(t$95$2 + N[(N[Power[l$95$m, 2.0], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(t$95$2 + N[Power[l$95$m, 2.0], $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[(-1.0 + x), $MachinePrecision] / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]]]), $MachinePrecision]]
\begin{array}{l}
l_m = \left|\ell\right|
\\
t_m = \left|t\right|
\\
t_s = \mathsf{copysign}\left(1, t\right)

\\
\begin{array}{l}
t_2 := 2 \cdot {t_m}^{2}\\
t_s \cdot \begin{array}{l}
\mathbf{if}\;t_m \leq 1.6 \cdot 10^{-247}:\\
\;\;\;\;\sqrt{2} \cdot \frac{t_m}{l_m \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\

\mathbf{elif}\;t_m \leq 2.35 \cdot 10^{-166}:\\
\;\;\;\;1\\

\mathbf{elif}\;t_m \leq 3 \cdot 10^{+84}:\\
\;\;\;\;t_m \cdot \frac{\sqrt{2}}{\sqrt{\left(2 \cdot \frac{{t_m}^{2}}{x} + \left(t_2 + \frac{{l_m}^{2}}{x}\right)\right) + \frac{t_2 + {l_m}^{2}}{x}}}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\


\end{array}
\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if t < 1.59999999999999997e-247

    1. Initial program 27.8%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified27.7%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(\frac{x + 1}{x + -1}, \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right), \ell \cdot \left(-\ell\right)\right)}}} \]
    3. Taylor expanded in l around inf 2.6%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{\ell \cdot \sqrt{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}}} \]
    4. Step-by-step derivation
      1. associate--l+10.4%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\color{blue}{\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)}}} \]
      2. sub-neg10.4%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      3. metadata-eval10.4%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      4. +-commutative10.4%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      5. sub-neg10.4%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)}} \]
      6. metadata-eval10.4%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)}} \]
      7. +-commutative10.4%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)}} \]
    5. Simplified10.4%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)}}} \]
    6. Taylor expanded in x around inf 21.4%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \color{blue}{\frac{1}{x}}}} \]

    if 1.59999999999999997e-247 < t < 2.35000000000000007e-166

    1. Initial program 2.8%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified2.8%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 59.9%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative59.9%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg59.9%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval59.9%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative59.9%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified59.9%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Taylor expanded in x around inf 59.9%

      \[\leadsto \color{blue}{1} \]

    if 2.35000000000000007e-166 < t < 2.99999999999999996e84

    1. Initial program 45.6%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified45.8%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right) - \ell \cdot \ell}} \cdot t} \]
    3. Taylor expanded in x around inf 78.7%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{\left(2 \cdot \frac{{t}^{2}}{x} + \left(2 \cdot {t}^{2} + \frac{{\ell}^{2}}{x}\right)\right) - -1 \cdot \frac{2 \cdot {t}^{2} + {\ell}^{2}}{x}}}} \cdot t \]

    if 2.99999999999999996e84 < t

    1. Initial program 23.3%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified23.3%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 100.0%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified100.0%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Step-by-step derivation
      1. sqrt-unprod100.0%

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      2. sqrt-undiv100.0%

        \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      3. +-commutative100.0%

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{\color{blue}{x + -1}}}} \]
    7. Applied egg-rr100.0%

      \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{x + -1}}}} \]
    8. Step-by-step derivation
      1. associate-/r*100.0%

        \[\leadsto \sqrt{\color{blue}{\frac{\frac{2}{2}}{\frac{x + 1}{x + -1}}}} \]
      2. metadata-eval100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{1}}{\frac{x + 1}{x + -1}}} \]
      3. +-commutative100.0%

        \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    9. Simplified100.0%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{x + 1}{-1 + x}}}} \]
    10. Step-by-step derivation
      1. expm1-log1p-u100.0%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)\right)}} \]
      2. expm1-udef100.0%

        \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)} - 1}} \]
      3. associate-/r/100.0%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\color{blue}{\frac{1}{x + 1} \cdot \left(-1 + x\right)}\right)} - 1} \]
      4. +-commutative100.0%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{1 + x}} \cdot \left(-1 + x\right)\right)} - 1} \]
      5. +-commutative100.0%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \color{blue}{\left(x + -1\right)}\right)} - 1} \]
    11. Applied egg-rr100.0%

      \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)} - 1}} \]
    12. Step-by-step derivation
      1. expm1-def100.0%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)\right)}} \]
      2. expm1-log1p99.5%

        \[\leadsto \sqrt{\color{blue}{\frac{1}{1 + x} \cdot \left(x + -1\right)}} \]
      3. metadata-eval99.5%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \left(x + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg99.5%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \color{blue}{\left(x - 1\right)}} \]
      5. associate-*l/100.0%

        \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot \left(x - 1\right)}{1 + x}}} \]
      6. *-lft-identity100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{x - 1}}{1 + x}} \]
      7. sub-neg100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{x + \left(-1\right)}}{1 + x}} \]
      8. metadata-eval100.0%

        \[\leadsto \sqrt{\frac{x + \color{blue}{-1}}{1 + x}} \]
      9. +-commutative100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{-1 + x}}{1 + x}} \]
      10. +-commutative100.0%

        \[\leadsto \sqrt{\frac{-1 + x}{\color{blue}{x + 1}}} \]
    13. Simplified100.0%

      \[\leadsto \sqrt{\color{blue}{\frac{-1 + x}{x + 1}}} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification51.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 1.6 \cdot 10^{-247}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\ \mathbf{elif}\;t \leq 2.35 \cdot 10^{-166}:\\ \;\;\;\;1\\ \mathbf{elif}\;t \leq 3 \cdot 10^{+84}:\\ \;\;\;\;t \cdot \frac{\sqrt{2}}{\sqrt{\left(2 \cdot \frac{{t}^{2}}{x} + \left(2 \cdot {t}^{2} + \frac{{\ell}^{2}}{x}\right)\right) + \frac{2 \cdot {t}^{2} + {\ell}^{2}}{x}}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \end{array} \]

Alternative 3: 85.3% accurate, 0.3× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ \begin{array}{l} t_2 := 2 \cdot {t_m}^{2}\\ t_3 := t_2 + {l_m}^{2}\\ t_s \cdot \begin{array}{l} \mathbf{if}\;t_m \leq 7.1 \cdot 10^{-258}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t_m}{l_m \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\ \mathbf{elif}\;t_m \leq 1.08 \cdot 10^{-165}:\\ \;\;\;\;t_m \cdot \frac{\sqrt{2}}{0.5 \cdot \frac{t_3 + t_3}{t_m \cdot \left(\sqrt{2} \cdot x\right)} + t_m \cdot \sqrt{2}}\\ \mathbf{elif}\;t_m \leq 4.1 \cdot 10^{+84}:\\ \;\;\;\;t_m \cdot \frac{\sqrt{2}}{\sqrt{\left(2 \cdot \frac{{t_m}^{2}}{x} + \left(t_2 + \frac{{l_m}^{2}}{x}\right)\right) + \frac{t_3}{x}}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \end{array} \end{array} \end{array} \]
l_m = (fabs.f64 l)
t_m = (fabs.f64 t)
t_s = (copysign.f64 1 t)
(FPCore (t_s x l_m t_m)
 :precision binary64
 (let* ((t_2 (* 2.0 (pow t_m 2.0))) (t_3 (+ t_2 (pow l_m 2.0))))
   (*
    t_s
    (if (<= t_m 7.1e-258)
      (* (sqrt 2.0) (/ t_m (* l_m (sqrt (+ (/ 1.0 (+ -1.0 x)) (/ 1.0 x))))))
      (if (<= t_m 1.08e-165)
        (*
         t_m
         (/
          (sqrt 2.0)
          (+
           (* 0.5 (/ (+ t_3 t_3) (* t_m (* (sqrt 2.0) x))))
           (* t_m (sqrt 2.0)))))
        (if (<= t_m 4.1e+84)
          (*
           t_m
           (/
            (sqrt 2.0)
            (sqrt
             (+
              (+ (* 2.0 (/ (pow t_m 2.0) x)) (+ t_2 (/ (pow l_m 2.0) x)))
              (/ t_3 x)))))
          (sqrt (/ (+ -1.0 x) (+ 1.0 x)))))))))
l_m = fabs(l);
t_m = fabs(t);
t_s = copysign(1.0, t);
double code(double t_s, double x, double l_m, double t_m) {
	double t_2 = 2.0 * pow(t_m, 2.0);
	double t_3 = t_2 + pow(l_m, 2.0);
	double tmp;
	if (t_m <= 7.1e-258) {
		tmp = sqrt(2.0) * (t_m / (l_m * sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	} else if (t_m <= 1.08e-165) {
		tmp = t_m * (sqrt(2.0) / ((0.5 * ((t_3 + t_3) / (t_m * (sqrt(2.0) * x)))) + (t_m * sqrt(2.0))));
	} else if (t_m <= 4.1e+84) {
		tmp = t_m * (sqrt(2.0) / sqrt((((2.0 * (pow(t_m, 2.0) / x)) + (t_2 + (pow(l_m, 2.0) / x))) + (t_3 / x))));
	} else {
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	}
	return t_s * tmp;
}
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0d0, t)
real(8) function code(t_s, x, l_m, t_m)
    real(8), intent (in) :: t_s
    real(8), intent (in) :: x
    real(8), intent (in) :: l_m
    real(8), intent (in) :: t_m
    real(8) :: t_2
    real(8) :: t_3
    real(8) :: tmp
    t_2 = 2.0d0 * (t_m ** 2.0d0)
    t_3 = t_2 + (l_m ** 2.0d0)
    if (t_m <= 7.1d-258) then
        tmp = sqrt(2.0d0) * (t_m / (l_m * sqrt(((1.0d0 / ((-1.0d0) + x)) + (1.0d0 / x)))))
    else if (t_m <= 1.08d-165) then
        tmp = t_m * (sqrt(2.0d0) / ((0.5d0 * ((t_3 + t_3) / (t_m * (sqrt(2.0d0) * x)))) + (t_m * sqrt(2.0d0))))
    else if (t_m <= 4.1d+84) then
        tmp = t_m * (sqrt(2.0d0) / sqrt((((2.0d0 * ((t_m ** 2.0d0) / x)) + (t_2 + ((l_m ** 2.0d0) / x))) + (t_3 / x))))
    else
        tmp = sqrt((((-1.0d0) + x) / (1.0d0 + x)))
    end if
    code = t_s * tmp
end function
l_m = Math.abs(l);
t_m = Math.abs(t);
t_s = Math.copySign(1.0, t);
public static double code(double t_s, double x, double l_m, double t_m) {
	double t_2 = 2.0 * Math.pow(t_m, 2.0);
	double t_3 = t_2 + Math.pow(l_m, 2.0);
	double tmp;
	if (t_m <= 7.1e-258) {
		tmp = Math.sqrt(2.0) * (t_m / (l_m * Math.sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	} else if (t_m <= 1.08e-165) {
		tmp = t_m * (Math.sqrt(2.0) / ((0.5 * ((t_3 + t_3) / (t_m * (Math.sqrt(2.0) * x)))) + (t_m * Math.sqrt(2.0))));
	} else if (t_m <= 4.1e+84) {
		tmp = t_m * (Math.sqrt(2.0) / Math.sqrt((((2.0 * (Math.pow(t_m, 2.0) / x)) + (t_2 + (Math.pow(l_m, 2.0) / x))) + (t_3 / x))));
	} else {
		tmp = Math.sqrt(((-1.0 + x) / (1.0 + x)));
	}
	return t_s * tmp;
}
l_m = math.fabs(l)
t_m = math.fabs(t)
t_s = math.copysign(1.0, t)
def code(t_s, x, l_m, t_m):
	t_2 = 2.0 * math.pow(t_m, 2.0)
	t_3 = t_2 + math.pow(l_m, 2.0)
	tmp = 0
	if t_m <= 7.1e-258:
		tmp = math.sqrt(2.0) * (t_m / (l_m * math.sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))))
	elif t_m <= 1.08e-165:
		tmp = t_m * (math.sqrt(2.0) / ((0.5 * ((t_3 + t_3) / (t_m * (math.sqrt(2.0) * x)))) + (t_m * math.sqrt(2.0))))
	elif t_m <= 4.1e+84:
		tmp = t_m * (math.sqrt(2.0) / math.sqrt((((2.0 * (math.pow(t_m, 2.0) / x)) + (t_2 + (math.pow(l_m, 2.0) / x))) + (t_3 / x))))
	else:
		tmp = math.sqrt(((-1.0 + x) / (1.0 + x)))
	return t_s * tmp
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0, t)
function code(t_s, x, l_m, t_m)
	t_2 = Float64(2.0 * (t_m ^ 2.0))
	t_3 = Float64(t_2 + (l_m ^ 2.0))
	tmp = 0.0
	if (t_m <= 7.1e-258)
		tmp = Float64(sqrt(2.0) * Float64(t_m / Float64(l_m * sqrt(Float64(Float64(1.0 / Float64(-1.0 + x)) + Float64(1.0 / x))))));
	elseif (t_m <= 1.08e-165)
		tmp = Float64(t_m * Float64(sqrt(2.0) / Float64(Float64(0.5 * Float64(Float64(t_3 + t_3) / Float64(t_m * Float64(sqrt(2.0) * x)))) + Float64(t_m * sqrt(2.0)))));
	elseif (t_m <= 4.1e+84)
		tmp = Float64(t_m * Float64(sqrt(2.0) / sqrt(Float64(Float64(Float64(2.0 * Float64((t_m ^ 2.0) / x)) + Float64(t_2 + Float64((l_m ^ 2.0) / x))) + Float64(t_3 / x)))));
	else
		tmp = sqrt(Float64(Float64(-1.0 + x) / Float64(1.0 + x)));
	end
	return Float64(t_s * tmp)
end
l_m = abs(l);
t_m = abs(t);
t_s = sign(t) * abs(1.0);
function tmp_2 = code(t_s, x, l_m, t_m)
	t_2 = 2.0 * (t_m ^ 2.0);
	t_3 = t_2 + (l_m ^ 2.0);
	tmp = 0.0;
	if (t_m <= 7.1e-258)
		tmp = sqrt(2.0) * (t_m / (l_m * sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	elseif (t_m <= 1.08e-165)
		tmp = t_m * (sqrt(2.0) / ((0.5 * ((t_3 + t_3) / (t_m * (sqrt(2.0) * x)))) + (t_m * sqrt(2.0))));
	elseif (t_m <= 4.1e+84)
		tmp = t_m * (sqrt(2.0) / sqrt((((2.0 * ((t_m ^ 2.0) / x)) + (t_2 + ((l_m ^ 2.0) / x))) + (t_3 / x))));
	else
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	end
	tmp_2 = t_s * tmp;
end
l_m = N[Abs[l], $MachinePrecision]
t_m = N[Abs[t], $MachinePrecision]
t_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[t$95$s_, x_, l$95$m_, t$95$m_] := Block[{t$95$2 = N[(2.0 * N[Power[t$95$m, 2.0], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(t$95$2 + N[Power[l$95$m, 2.0], $MachinePrecision]), $MachinePrecision]}, N[(t$95$s * If[LessEqual[t$95$m, 7.1e-258], N[(N[Sqrt[2.0], $MachinePrecision] * N[(t$95$m / N[(l$95$m * N[Sqrt[N[(N[(1.0 / N[(-1.0 + x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$m, 1.08e-165], N[(t$95$m * N[(N[Sqrt[2.0], $MachinePrecision] / N[(N[(0.5 * N[(N[(t$95$3 + t$95$3), $MachinePrecision] / N[(t$95$m * N[(N[Sqrt[2.0], $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$m * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$m, 4.1e+84], N[(t$95$m * N[(N[Sqrt[2.0], $MachinePrecision] / N[Sqrt[N[(N[(N[(2.0 * N[(N[Power[t$95$m, 2.0], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] + N[(t$95$2 + N[(N[Power[l$95$m, 2.0], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$3 / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[(-1.0 + x), $MachinePrecision] / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]]]), $MachinePrecision]]]
\begin{array}{l}
l_m = \left|\ell\right|
\\
t_m = \left|t\right|
\\
t_s = \mathsf{copysign}\left(1, t\right)

\\
\begin{array}{l}
t_2 := 2 \cdot {t_m}^{2}\\
t_3 := t_2 + {l_m}^{2}\\
t_s \cdot \begin{array}{l}
\mathbf{if}\;t_m \leq 7.1 \cdot 10^{-258}:\\
\;\;\;\;\sqrt{2} \cdot \frac{t_m}{l_m \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\

\mathbf{elif}\;t_m \leq 1.08 \cdot 10^{-165}:\\
\;\;\;\;t_m \cdot \frac{\sqrt{2}}{0.5 \cdot \frac{t_3 + t_3}{t_m \cdot \left(\sqrt{2} \cdot x\right)} + t_m \cdot \sqrt{2}}\\

\mathbf{elif}\;t_m \leq 4.1 \cdot 10^{+84}:\\
\;\;\;\;t_m \cdot \frac{\sqrt{2}}{\sqrt{\left(2 \cdot \frac{{t_m}^{2}}{x} + \left(t_2 + \frac{{l_m}^{2}}{x}\right)\right) + \frac{t_3}{x}}}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\


\end{array}
\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if t < 7.0999999999999998e-258

    1. Initial program 28.2%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified28.1%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(\frac{x + 1}{x + -1}, \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right), \ell \cdot \left(-\ell\right)\right)}}} \]
    3. Taylor expanded in l around inf 2.7%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{\ell \cdot \sqrt{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}}} \]
    4. Step-by-step derivation
      1. associate--l+9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\color{blue}{\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)}}} \]
      2. sub-neg9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      3. metadata-eval9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      4. +-commutative9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      5. sub-neg9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)}} \]
      6. metadata-eval9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)}} \]
      7. +-commutative9.8%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)}} \]
    5. Simplified9.8%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)}}} \]
    6. Taylor expanded in x around inf 20.9%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \color{blue}{\frac{1}{x}}}} \]

    if 7.0999999999999998e-258 < t < 1.08000000000000003e-165

    1. Initial program 2.6%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified2.6%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right) - \ell \cdot \ell}} \cdot t} \]
    3. Taylor expanded in x around inf 67.3%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{0.5 \cdot \frac{\left(2 \cdot {t}^{2} + {\ell}^{2}\right) - -1 \cdot \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)} + t \cdot \sqrt{2}}} \cdot t \]

    if 1.08000000000000003e-165 < t < 4.1000000000000003e84

    1. Initial program 45.6%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified45.8%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right) - \ell \cdot \ell}} \cdot t} \]
    3. Taylor expanded in x around inf 78.7%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{\color{blue}{\left(2 \cdot \frac{{t}^{2}}{x} + \left(2 \cdot {t}^{2} + \frac{{\ell}^{2}}{x}\right)\right) - -1 \cdot \frac{2 \cdot {t}^{2} + {\ell}^{2}}{x}}}} \cdot t \]

    if 4.1000000000000003e84 < t

    1. Initial program 23.3%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified23.3%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 100.0%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative100.0%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified100.0%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Step-by-step derivation
      1. sqrt-unprod100.0%

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      2. sqrt-undiv100.0%

        \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      3. +-commutative100.0%

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{\color{blue}{x + -1}}}} \]
    7. Applied egg-rr100.0%

      \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{x + -1}}}} \]
    8. Step-by-step derivation
      1. associate-/r*100.0%

        \[\leadsto \sqrt{\color{blue}{\frac{\frac{2}{2}}{\frac{x + 1}{x + -1}}}} \]
      2. metadata-eval100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{1}}{\frac{x + 1}{x + -1}}} \]
      3. +-commutative100.0%

        \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    9. Simplified100.0%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{x + 1}{-1 + x}}}} \]
    10. Step-by-step derivation
      1. expm1-log1p-u100.0%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)\right)}} \]
      2. expm1-udef100.0%

        \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)} - 1}} \]
      3. associate-/r/100.0%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\color{blue}{\frac{1}{x + 1} \cdot \left(-1 + x\right)}\right)} - 1} \]
      4. +-commutative100.0%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{1 + x}} \cdot \left(-1 + x\right)\right)} - 1} \]
      5. +-commutative100.0%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \color{blue}{\left(x + -1\right)}\right)} - 1} \]
    11. Applied egg-rr100.0%

      \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)} - 1}} \]
    12. Step-by-step derivation
      1. expm1-def100.0%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)\right)}} \]
      2. expm1-log1p99.5%

        \[\leadsto \sqrt{\color{blue}{\frac{1}{1 + x} \cdot \left(x + -1\right)}} \]
      3. metadata-eval99.5%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \left(x + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg99.5%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \color{blue}{\left(x - 1\right)}} \]
      5. associate-*l/100.0%

        \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot \left(x - 1\right)}{1 + x}}} \]
      6. *-lft-identity100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{x - 1}}{1 + x}} \]
      7. sub-neg100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{x + \left(-1\right)}}{1 + x}} \]
      8. metadata-eval100.0%

        \[\leadsto \sqrt{\frac{x + \color{blue}{-1}}{1 + x}} \]
      9. +-commutative100.0%

        \[\leadsto \sqrt{\frac{\color{blue}{-1 + x}}{1 + x}} \]
      10. +-commutative100.0%

        \[\leadsto \sqrt{\frac{-1 + x}{\color{blue}{x + 1}}} \]
    13. Simplified100.0%

      \[\leadsto \sqrt{\color{blue}{\frac{-1 + x}{x + 1}}} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification52.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 7.1 \cdot 10^{-258}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\ \mathbf{elif}\;t \leq 1.08 \cdot 10^{-165}:\\ \;\;\;\;t \cdot \frac{\sqrt{2}}{0.5 \cdot \frac{\left(2 \cdot {t}^{2} + {\ell}^{2}\right) + \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{t \cdot \left(\sqrt{2} \cdot x\right)} + t \cdot \sqrt{2}}\\ \mathbf{elif}\;t \leq 4.1 \cdot 10^{+84}:\\ \;\;\;\;t \cdot \frac{\sqrt{2}}{\sqrt{\left(2 \cdot \frac{{t}^{2}}{x} + \left(2 \cdot {t}^{2} + \frac{{\ell}^{2}}{x}\right)\right) + \frac{2 \cdot {t}^{2} + {\ell}^{2}}{x}}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \end{array} \]

Alternative 4: 79.3% accurate, 0.4× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ t_s \cdot \begin{array}{l} \mathbf{if}\;\frac{t_m \cdot \sqrt{2}}{\sqrt{\frac{1 + x}{-1 + x} \cdot \left(l_m \cdot l_m + 2 \cdot \left(t_m \cdot t_m\right)\right) - l_m \cdot l_m}} \leq 2:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t_m \cdot \sqrt{\mathsf{fma}\left(x, 0.5, -0.5\right)}}{l_m}\\ \end{array} \end{array} \]
l_m = (fabs.f64 l)
t_m = (fabs.f64 t)
t_s = (copysign.f64 1 t)
(FPCore (t_s x l_m t_m)
 :precision binary64
 (*
  t_s
  (if (<=
       (/
        (* t_m (sqrt 2.0))
        (sqrt
         (-
          (* (/ (+ 1.0 x) (+ -1.0 x)) (+ (* l_m l_m) (* 2.0 (* t_m t_m))))
          (* l_m l_m))))
       2.0)
    (sqrt (/ (+ -1.0 x) (+ 1.0 x)))
    (* (sqrt 2.0) (/ (* t_m (sqrt (fma x 0.5 -0.5))) l_m)))))
l_m = fabs(l);
t_m = fabs(t);
t_s = copysign(1.0, t);
double code(double t_s, double x, double l_m, double t_m) {
	double tmp;
	if (((t_m * sqrt(2.0)) / sqrt(((((1.0 + x) / (-1.0 + x)) * ((l_m * l_m) + (2.0 * (t_m * t_m)))) - (l_m * l_m)))) <= 2.0) {
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	} else {
		tmp = sqrt(2.0) * ((t_m * sqrt(fma(x, 0.5, -0.5))) / l_m);
	}
	return t_s * tmp;
}
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0, t)
function code(t_s, x, l_m, t_m)
	tmp = 0.0
	if (Float64(Float64(t_m * sqrt(2.0)) / sqrt(Float64(Float64(Float64(Float64(1.0 + x) / Float64(-1.0 + x)) * Float64(Float64(l_m * l_m) + Float64(2.0 * Float64(t_m * t_m)))) - Float64(l_m * l_m)))) <= 2.0)
		tmp = sqrt(Float64(Float64(-1.0 + x) / Float64(1.0 + x)));
	else
		tmp = Float64(sqrt(2.0) * Float64(Float64(t_m * sqrt(fma(x, 0.5, -0.5))) / l_m));
	end
	return Float64(t_s * tmp)
end
l_m = N[Abs[l], $MachinePrecision]
t_m = N[Abs[t], $MachinePrecision]
t_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[t$95$s_, x_, l$95$m_, t$95$m_] := N[(t$95$s * If[LessEqual[N[(N[(t$95$m * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] / N[Sqrt[N[(N[(N[(N[(1.0 + x), $MachinePrecision] / N[(-1.0 + x), $MachinePrecision]), $MachinePrecision] * N[(N[(l$95$m * l$95$m), $MachinePrecision] + N[(2.0 * N[(t$95$m * t$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(l$95$m * l$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], 2.0], N[Sqrt[N[(N[(-1.0 + x), $MachinePrecision] / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[(N[Sqrt[2.0], $MachinePrecision] * N[(N[(t$95$m * N[Sqrt[N[(x * 0.5 + -0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / l$95$m), $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]
\begin{array}{l}
l_m = \left|\ell\right|
\\
t_m = \left|t\right|
\\
t_s = \mathsf{copysign}\left(1, t\right)

\\
t_s \cdot \begin{array}{l}
\mathbf{if}\;\frac{t_m \cdot \sqrt{2}}{\sqrt{\frac{1 + x}{-1 + x} \cdot \left(l_m \cdot l_m + 2 \cdot \left(t_m \cdot t_m\right)\right) - l_m \cdot l_m}} \leq 2:\\
\;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{2} \cdot \frac{t_m \cdot \sqrt{\mathsf{fma}\left(x, 0.5, -0.5\right)}}{l_m}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (*.f64 (sqrt.f64 2) t) (sqrt.f64 (-.f64 (*.f64 (/.f64 (+.f64 x 1) (-.f64 x 1)) (+.f64 (*.f64 l l) (*.f64 2 (*.f64 t t)))) (*.f64 l l)))) < 2

    1. Initial program 45.0%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified45.0%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 41.4%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative41.4%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg41.4%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval41.4%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative41.4%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified41.4%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Step-by-step derivation
      1. sqrt-unprod41.5%

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      2. sqrt-undiv41.5%

        \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      3. +-commutative41.5%

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{\color{blue}{x + -1}}}} \]
    7. Applied egg-rr41.5%

      \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{x + -1}}}} \]
    8. Step-by-step derivation
      1. associate-/r*41.5%

        \[\leadsto \sqrt{\color{blue}{\frac{\frac{2}{2}}{\frac{x + 1}{x + -1}}}} \]
      2. metadata-eval41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{1}}{\frac{x + 1}{x + -1}}} \]
      3. +-commutative41.5%

        \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    9. Simplified41.5%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{x + 1}{-1 + x}}}} \]
    10. Step-by-step derivation
      1. expm1-log1p-u41.5%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)\right)}} \]
      2. expm1-udef41.5%

        \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)} - 1}} \]
      3. associate-/r/41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\color{blue}{\frac{1}{x + 1} \cdot \left(-1 + x\right)}\right)} - 1} \]
      4. +-commutative41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{1 + x}} \cdot \left(-1 + x\right)\right)} - 1} \]
      5. +-commutative41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \color{blue}{\left(x + -1\right)}\right)} - 1} \]
    11. Applied egg-rr41.5%

      \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)} - 1}} \]
    12. Step-by-step derivation
      1. expm1-def41.5%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)\right)}} \]
      2. expm1-log1p41.3%

        \[\leadsto \sqrt{\color{blue}{\frac{1}{1 + x} \cdot \left(x + -1\right)}} \]
      3. metadata-eval41.3%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \left(x + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg41.3%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \color{blue}{\left(x - 1\right)}} \]
      5. associate-*l/41.5%

        \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot \left(x - 1\right)}{1 + x}}} \]
      6. *-lft-identity41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{x - 1}}{1 + x}} \]
      7. sub-neg41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{x + \left(-1\right)}}{1 + x}} \]
      8. metadata-eval41.5%

        \[\leadsto \sqrt{\frac{x + \color{blue}{-1}}{1 + x}} \]
      9. +-commutative41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{-1 + x}}{1 + x}} \]
      10. +-commutative41.5%

        \[\leadsto \sqrt{\frac{-1 + x}{\color{blue}{x + 1}}} \]
    13. Simplified41.5%

      \[\leadsto \sqrt{\color{blue}{\frac{-1 + x}{x + 1}}} \]

    if 2 < (/.f64 (*.f64 (sqrt.f64 2) t) (sqrt.f64 (-.f64 (*.f64 (/.f64 (+.f64 x 1) (-.f64 x 1)) (+.f64 (*.f64 l l) (*.f64 2 (*.f64 t t)))) (*.f64 l l))))

    1. Initial program 1.2%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified1.2%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(\frac{x + 1}{x + -1}, \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right), \ell \cdot \left(-\ell\right)\right)}}} \]
    3. Taylor expanded in l around inf 1.5%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\frac{t}{\ell} \cdot \sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}}\right)} \]
    4. Step-by-step derivation
      1. *-commutative1.5%

        \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}} \cdot \frac{t}{\ell}\right)} \]
      2. associate--l+17.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\color{blue}{\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)}}} \cdot \frac{t}{\ell}\right) \]
      3. sub-neg17.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      4. metadata-eval17.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      5. +-commutative17.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      6. sub-neg17.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      7. metadata-eval17.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      8. +-commutative17.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
    5. Simplified17.3%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)}} \cdot \frac{t}{\ell}\right)} \]
    6. Taylor expanded in x around 0 37.3%

      \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{0.5 \cdot x - 0.5}} \cdot \frac{t}{\ell}\right) \]
    7. Step-by-step derivation
      1. associate-*r/38.7%

        \[\leadsto \sqrt{2} \cdot \color{blue}{\frac{\sqrt{0.5 \cdot x - 0.5} \cdot t}{\ell}} \]
      2. *-commutative38.7%

        \[\leadsto \sqrt{2} \cdot \frac{\sqrt{\color{blue}{x \cdot 0.5} - 0.5} \cdot t}{\ell} \]
      3. fma-neg38.7%

        \[\leadsto \sqrt{2} \cdot \frac{\sqrt{\color{blue}{\mathsf{fma}\left(x, 0.5, -0.5\right)}} \cdot t}{\ell} \]
      4. metadata-eval38.7%

        \[\leadsto \sqrt{2} \cdot \frac{\sqrt{\mathsf{fma}\left(x, 0.5, \color{blue}{-0.5}\right)} \cdot t}{\ell} \]
    8. Applied egg-rr38.7%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\frac{\sqrt{\mathsf{fma}\left(x, 0.5, -0.5\right)} \cdot t}{\ell}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification40.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{t \cdot \sqrt{2}}{\sqrt{\frac{1 + x}{-1 + x} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \leq 2:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t \cdot \sqrt{\mathsf{fma}\left(x, 0.5, -0.5\right)}}{\ell}\\ \end{array} \]

Alternative 5: 79.1% accurate, 0.5× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ t_s \cdot \begin{array}{l} \mathbf{if}\;\frac{t_m \cdot \sqrt{2}}{\sqrt{\frac{1 + x}{-1 + x} \cdot \left(l_m \cdot l_m + 2 \cdot \left(t_m \cdot t_m\right)\right) - l_m \cdot l_m}} \leq 2:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t_m}{l_m \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\ \end{array} \end{array} \]
l_m = (fabs.f64 l)
t_m = (fabs.f64 t)
t_s = (copysign.f64 1 t)
(FPCore (t_s x l_m t_m)
 :precision binary64
 (*
  t_s
  (if (<=
       (/
        (* t_m (sqrt 2.0))
        (sqrt
         (-
          (* (/ (+ 1.0 x) (+ -1.0 x)) (+ (* l_m l_m) (* 2.0 (* t_m t_m))))
          (* l_m l_m))))
       2.0)
    (sqrt (/ (+ -1.0 x) (+ 1.0 x)))
    (* (sqrt 2.0) (/ t_m (* l_m (sqrt (+ (/ 1.0 (+ -1.0 x)) (/ 1.0 x)))))))))
l_m = fabs(l);
t_m = fabs(t);
t_s = copysign(1.0, t);
double code(double t_s, double x, double l_m, double t_m) {
	double tmp;
	if (((t_m * sqrt(2.0)) / sqrt(((((1.0 + x) / (-1.0 + x)) * ((l_m * l_m) + (2.0 * (t_m * t_m)))) - (l_m * l_m)))) <= 2.0) {
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	} else {
		tmp = sqrt(2.0) * (t_m / (l_m * sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	}
	return t_s * tmp;
}
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0d0, t)
real(8) function code(t_s, x, l_m, t_m)
    real(8), intent (in) :: t_s
    real(8), intent (in) :: x
    real(8), intent (in) :: l_m
    real(8), intent (in) :: t_m
    real(8) :: tmp
    if (((t_m * sqrt(2.0d0)) / sqrt(((((1.0d0 + x) / ((-1.0d0) + x)) * ((l_m * l_m) + (2.0d0 * (t_m * t_m)))) - (l_m * l_m)))) <= 2.0d0) then
        tmp = sqrt((((-1.0d0) + x) / (1.0d0 + x)))
    else
        tmp = sqrt(2.0d0) * (t_m / (l_m * sqrt(((1.0d0 / ((-1.0d0) + x)) + (1.0d0 / x)))))
    end if
    code = t_s * tmp
end function
l_m = Math.abs(l);
t_m = Math.abs(t);
t_s = Math.copySign(1.0, t);
public static double code(double t_s, double x, double l_m, double t_m) {
	double tmp;
	if (((t_m * Math.sqrt(2.0)) / Math.sqrt(((((1.0 + x) / (-1.0 + x)) * ((l_m * l_m) + (2.0 * (t_m * t_m)))) - (l_m * l_m)))) <= 2.0) {
		tmp = Math.sqrt(((-1.0 + x) / (1.0 + x)));
	} else {
		tmp = Math.sqrt(2.0) * (t_m / (l_m * Math.sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	}
	return t_s * tmp;
}
l_m = math.fabs(l)
t_m = math.fabs(t)
t_s = math.copysign(1.0, t)
def code(t_s, x, l_m, t_m):
	tmp = 0
	if ((t_m * math.sqrt(2.0)) / math.sqrt(((((1.0 + x) / (-1.0 + x)) * ((l_m * l_m) + (2.0 * (t_m * t_m)))) - (l_m * l_m)))) <= 2.0:
		tmp = math.sqrt(((-1.0 + x) / (1.0 + x)))
	else:
		tmp = math.sqrt(2.0) * (t_m / (l_m * math.sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))))
	return t_s * tmp
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0, t)
function code(t_s, x, l_m, t_m)
	tmp = 0.0
	if (Float64(Float64(t_m * sqrt(2.0)) / sqrt(Float64(Float64(Float64(Float64(1.0 + x) / Float64(-1.0 + x)) * Float64(Float64(l_m * l_m) + Float64(2.0 * Float64(t_m * t_m)))) - Float64(l_m * l_m)))) <= 2.0)
		tmp = sqrt(Float64(Float64(-1.0 + x) / Float64(1.0 + x)));
	else
		tmp = Float64(sqrt(2.0) * Float64(t_m / Float64(l_m * sqrt(Float64(Float64(1.0 / Float64(-1.0 + x)) + Float64(1.0 / x))))));
	end
	return Float64(t_s * tmp)
end
l_m = abs(l);
t_m = abs(t);
t_s = sign(t) * abs(1.0);
function tmp_2 = code(t_s, x, l_m, t_m)
	tmp = 0.0;
	if (((t_m * sqrt(2.0)) / sqrt(((((1.0 + x) / (-1.0 + x)) * ((l_m * l_m) + (2.0 * (t_m * t_m)))) - (l_m * l_m)))) <= 2.0)
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	else
		tmp = sqrt(2.0) * (t_m / (l_m * sqrt(((1.0 / (-1.0 + x)) + (1.0 / x)))));
	end
	tmp_2 = t_s * tmp;
end
l_m = N[Abs[l], $MachinePrecision]
t_m = N[Abs[t], $MachinePrecision]
t_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[t$95$s_, x_, l$95$m_, t$95$m_] := N[(t$95$s * If[LessEqual[N[(N[(t$95$m * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] / N[Sqrt[N[(N[(N[(N[(1.0 + x), $MachinePrecision] / N[(-1.0 + x), $MachinePrecision]), $MachinePrecision] * N[(N[(l$95$m * l$95$m), $MachinePrecision] + N[(2.0 * N[(t$95$m * t$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(l$95$m * l$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], 2.0], N[Sqrt[N[(N[(-1.0 + x), $MachinePrecision] / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[(N[Sqrt[2.0], $MachinePrecision] * N[(t$95$m / N[(l$95$m * N[Sqrt[N[(N[(1.0 / N[(-1.0 + x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]), $MachinePrecision]
\begin{array}{l}
l_m = \left|\ell\right|
\\
t_m = \left|t\right|
\\
t_s = \mathsf{copysign}\left(1, t\right)

\\
t_s \cdot \begin{array}{l}
\mathbf{if}\;\frac{t_m \cdot \sqrt{2}}{\sqrt{\frac{1 + x}{-1 + x} \cdot \left(l_m \cdot l_m + 2 \cdot \left(t_m \cdot t_m\right)\right) - l_m \cdot l_m}} \leq 2:\\
\;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{2} \cdot \frac{t_m}{l_m \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (*.f64 (sqrt.f64 2) t) (sqrt.f64 (-.f64 (*.f64 (/.f64 (+.f64 x 1) (-.f64 x 1)) (+.f64 (*.f64 l l) (*.f64 2 (*.f64 t t)))) (*.f64 l l)))) < 2

    1. Initial program 45.0%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified45.0%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 41.4%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative41.4%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg41.4%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval41.4%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative41.4%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified41.4%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Step-by-step derivation
      1. sqrt-unprod41.5%

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      2. sqrt-undiv41.5%

        \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      3. +-commutative41.5%

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{\color{blue}{x + -1}}}} \]
    7. Applied egg-rr41.5%

      \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{x + -1}}}} \]
    8. Step-by-step derivation
      1. associate-/r*41.5%

        \[\leadsto \sqrt{\color{blue}{\frac{\frac{2}{2}}{\frac{x + 1}{x + -1}}}} \]
      2. metadata-eval41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{1}}{\frac{x + 1}{x + -1}}} \]
      3. +-commutative41.5%

        \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    9. Simplified41.5%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{x + 1}{-1 + x}}}} \]
    10. Step-by-step derivation
      1. expm1-log1p-u41.5%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)\right)}} \]
      2. expm1-udef41.5%

        \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)} - 1}} \]
      3. associate-/r/41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\color{blue}{\frac{1}{x + 1} \cdot \left(-1 + x\right)}\right)} - 1} \]
      4. +-commutative41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{1 + x}} \cdot \left(-1 + x\right)\right)} - 1} \]
      5. +-commutative41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \color{blue}{\left(x + -1\right)}\right)} - 1} \]
    11. Applied egg-rr41.5%

      \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)} - 1}} \]
    12. Step-by-step derivation
      1. expm1-def41.5%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)\right)}} \]
      2. expm1-log1p41.3%

        \[\leadsto \sqrt{\color{blue}{\frac{1}{1 + x} \cdot \left(x + -1\right)}} \]
      3. metadata-eval41.3%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \left(x + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg41.3%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \color{blue}{\left(x - 1\right)}} \]
      5. associate-*l/41.5%

        \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot \left(x - 1\right)}{1 + x}}} \]
      6. *-lft-identity41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{x - 1}}{1 + x}} \]
      7. sub-neg41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{x + \left(-1\right)}}{1 + x}} \]
      8. metadata-eval41.5%

        \[\leadsto \sqrt{\frac{x + \color{blue}{-1}}{1 + x}} \]
      9. +-commutative41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{-1 + x}}{1 + x}} \]
      10. +-commutative41.5%

        \[\leadsto \sqrt{\frac{-1 + x}{\color{blue}{x + 1}}} \]
    13. Simplified41.5%

      \[\leadsto \sqrt{\color{blue}{\frac{-1 + x}{x + 1}}} \]

    if 2 < (/.f64 (*.f64 (sqrt.f64 2) t) (sqrt.f64 (-.f64 (*.f64 (/.f64 (+.f64 x 1) (-.f64 x 1)) (+.f64 (*.f64 l l) (*.f64 2 (*.f64 t t)))) (*.f64 l l))))

    1. Initial program 1.2%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified1.2%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(\frac{x + 1}{x + -1}, \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right), \ell \cdot \left(-\ell\right)\right)}}} \]
    3. Taylor expanded in l around inf 1.8%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{\ell \cdot \sqrt{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}}} \]
    4. Step-by-step derivation
      1. associate--l+17.3%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\color{blue}{\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)}}} \]
      2. sub-neg17.3%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      3. metadata-eval17.3%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      4. +-commutative17.3%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)}} \]
      5. sub-neg17.3%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)}} \]
      6. metadata-eval17.3%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)}} \]
      7. +-commutative17.3%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)}} \]
    5. Simplified17.3%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)}}} \]
    6. Taylor expanded in x around inf 38.6%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \color{blue}{\frac{1}{x}}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification40.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{t \cdot \sqrt{2}}{\sqrt{\frac{1 + x}{-1 + x} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \leq 2:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t}{\ell \cdot \sqrt{\frac{1}{-1 + x} + \frac{1}{x}}}\\ \end{array} \]

Alternative 6: 79.0% accurate, 1.0× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ t_s \cdot \begin{array}{l} \mathbf{if}\;l_m \leq 1.82 \cdot 10^{+93}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \mathbf{elif}\;l_m \leq 4.2 \cdot 10^{+108}:\\ \;\;\;\;\sqrt{2} \cdot \left(\sqrt{x \cdot 0.5} \cdot \frac{t_m}{l_m}\right)\\ \mathbf{elif}\;l_m \leq 4.8 \cdot 10^{+178}:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;\frac{t_m \cdot \sqrt{2}}{l_m} \cdot \sqrt{x \cdot 0.5 - 0.5}\\ \end{array} \end{array} \]
l_m = (fabs.f64 l)
t_m = (fabs.f64 t)
t_s = (copysign.f64 1 t)
(FPCore (t_s x l_m t_m)
 :precision binary64
 (*
  t_s
  (if (<= l_m 1.82e+93)
    (sqrt (/ (+ -1.0 x) (+ 1.0 x)))
    (if (<= l_m 4.2e+108)
      (* (sqrt 2.0) (* (sqrt (* x 0.5)) (/ t_m l_m)))
      (if (<= l_m 4.8e+178)
        1.0
        (* (/ (* t_m (sqrt 2.0)) l_m) (sqrt (- (* x 0.5) 0.5))))))))
l_m = fabs(l);
t_m = fabs(t);
t_s = copysign(1.0, t);
double code(double t_s, double x, double l_m, double t_m) {
	double tmp;
	if (l_m <= 1.82e+93) {
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	} else if (l_m <= 4.2e+108) {
		tmp = sqrt(2.0) * (sqrt((x * 0.5)) * (t_m / l_m));
	} else if (l_m <= 4.8e+178) {
		tmp = 1.0;
	} else {
		tmp = ((t_m * sqrt(2.0)) / l_m) * sqrt(((x * 0.5) - 0.5));
	}
	return t_s * tmp;
}
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0d0, t)
real(8) function code(t_s, x, l_m, t_m)
    real(8), intent (in) :: t_s
    real(8), intent (in) :: x
    real(8), intent (in) :: l_m
    real(8), intent (in) :: t_m
    real(8) :: tmp
    if (l_m <= 1.82d+93) then
        tmp = sqrt((((-1.0d0) + x) / (1.0d0 + x)))
    else if (l_m <= 4.2d+108) then
        tmp = sqrt(2.0d0) * (sqrt((x * 0.5d0)) * (t_m / l_m))
    else if (l_m <= 4.8d+178) then
        tmp = 1.0d0
    else
        tmp = ((t_m * sqrt(2.0d0)) / l_m) * sqrt(((x * 0.5d0) - 0.5d0))
    end if
    code = t_s * tmp
end function
l_m = Math.abs(l);
t_m = Math.abs(t);
t_s = Math.copySign(1.0, t);
public static double code(double t_s, double x, double l_m, double t_m) {
	double tmp;
	if (l_m <= 1.82e+93) {
		tmp = Math.sqrt(((-1.0 + x) / (1.0 + x)));
	} else if (l_m <= 4.2e+108) {
		tmp = Math.sqrt(2.0) * (Math.sqrt((x * 0.5)) * (t_m / l_m));
	} else if (l_m <= 4.8e+178) {
		tmp = 1.0;
	} else {
		tmp = ((t_m * Math.sqrt(2.0)) / l_m) * Math.sqrt(((x * 0.5) - 0.5));
	}
	return t_s * tmp;
}
l_m = math.fabs(l)
t_m = math.fabs(t)
t_s = math.copysign(1.0, t)
def code(t_s, x, l_m, t_m):
	tmp = 0
	if l_m <= 1.82e+93:
		tmp = math.sqrt(((-1.0 + x) / (1.0 + x)))
	elif l_m <= 4.2e+108:
		tmp = math.sqrt(2.0) * (math.sqrt((x * 0.5)) * (t_m / l_m))
	elif l_m <= 4.8e+178:
		tmp = 1.0
	else:
		tmp = ((t_m * math.sqrt(2.0)) / l_m) * math.sqrt(((x * 0.5) - 0.5))
	return t_s * tmp
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0, t)
function code(t_s, x, l_m, t_m)
	tmp = 0.0
	if (l_m <= 1.82e+93)
		tmp = sqrt(Float64(Float64(-1.0 + x) / Float64(1.0 + x)));
	elseif (l_m <= 4.2e+108)
		tmp = Float64(sqrt(2.0) * Float64(sqrt(Float64(x * 0.5)) * Float64(t_m / l_m)));
	elseif (l_m <= 4.8e+178)
		tmp = 1.0;
	else
		tmp = Float64(Float64(Float64(t_m * sqrt(2.0)) / l_m) * sqrt(Float64(Float64(x * 0.5) - 0.5)));
	end
	return Float64(t_s * tmp)
end
l_m = abs(l);
t_m = abs(t);
t_s = sign(t) * abs(1.0);
function tmp_2 = code(t_s, x, l_m, t_m)
	tmp = 0.0;
	if (l_m <= 1.82e+93)
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	elseif (l_m <= 4.2e+108)
		tmp = sqrt(2.0) * (sqrt((x * 0.5)) * (t_m / l_m));
	elseif (l_m <= 4.8e+178)
		tmp = 1.0;
	else
		tmp = ((t_m * sqrt(2.0)) / l_m) * sqrt(((x * 0.5) - 0.5));
	end
	tmp_2 = t_s * tmp;
end
l_m = N[Abs[l], $MachinePrecision]
t_m = N[Abs[t], $MachinePrecision]
t_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[t$95$s_, x_, l$95$m_, t$95$m_] := N[(t$95$s * If[LessEqual[l$95$m, 1.82e+93], N[Sqrt[N[(N[(-1.0 + x), $MachinePrecision] / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], If[LessEqual[l$95$m, 4.2e+108], N[(N[Sqrt[2.0], $MachinePrecision] * N[(N[Sqrt[N[(x * 0.5), $MachinePrecision]], $MachinePrecision] * N[(t$95$m / l$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[l$95$m, 4.8e+178], 1.0, N[(N[(N[(t$95$m * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] / l$95$m), $MachinePrecision] * N[Sqrt[N[(N[(x * 0.5), $MachinePrecision] - 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]), $MachinePrecision]
\begin{array}{l}
l_m = \left|\ell\right|
\\
t_m = \left|t\right|
\\
t_s = \mathsf{copysign}\left(1, t\right)

\\
t_s \cdot \begin{array}{l}
\mathbf{if}\;l_m \leq 1.82 \cdot 10^{+93}:\\
\;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\

\mathbf{elif}\;l_m \leq 4.2 \cdot 10^{+108}:\\
\;\;\;\;\sqrt{2} \cdot \left(\sqrt{x \cdot 0.5} \cdot \frac{t_m}{l_m}\right)\\

\mathbf{elif}\;l_m \leq 4.8 \cdot 10^{+178}:\\
\;\;\;\;1\\

\mathbf{else}:\\
\;\;\;\;\frac{t_m \cdot \sqrt{2}}{l_m} \cdot \sqrt{x \cdot 0.5 - 0.5}\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if l < 1.82000000000000009e93

    1. Initial program 34.2%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified34.2%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 41.5%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified41.5%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Step-by-step derivation
      1. sqrt-unprod41.5%

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      2. sqrt-undiv41.5%

        \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      3. +-commutative41.5%

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{\color{blue}{x + -1}}}} \]
    7. Applied egg-rr41.5%

      \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{x + -1}}}} \]
    8. Step-by-step derivation
      1. associate-/r*41.5%

        \[\leadsto \sqrt{\color{blue}{\frac{\frac{2}{2}}{\frac{x + 1}{x + -1}}}} \]
      2. metadata-eval41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{1}}{\frac{x + 1}{x + -1}}} \]
      3. +-commutative41.5%

        \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    9. Simplified41.5%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{x + 1}{-1 + x}}}} \]
    10. Step-by-step derivation
      1. expm1-log1p-u41.5%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)\right)}} \]
      2. expm1-udef41.5%

        \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)} - 1}} \]
      3. associate-/r/41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\color{blue}{\frac{1}{x + 1} \cdot \left(-1 + x\right)}\right)} - 1} \]
      4. +-commutative41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{1 + x}} \cdot \left(-1 + x\right)\right)} - 1} \]
      5. +-commutative41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \color{blue}{\left(x + -1\right)}\right)} - 1} \]
    11. Applied egg-rr41.5%

      \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)} - 1}} \]
    12. Step-by-step derivation
      1. expm1-def41.5%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)\right)}} \]
      2. expm1-log1p41.4%

        \[\leadsto \sqrt{\color{blue}{\frac{1}{1 + x} \cdot \left(x + -1\right)}} \]
      3. metadata-eval41.4%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \left(x + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg41.4%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \color{blue}{\left(x - 1\right)}} \]
      5. associate-*l/41.5%

        \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot \left(x - 1\right)}{1 + x}}} \]
      6. *-lft-identity41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{x - 1}}{1 + x}} \]
      7. sub-neg41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{x + \left(-1\right)}}{1 + x}} \]
      8. metadata-eval41.5%

        \[\leadsto \sqrt{\frac{x + \color{blue}{-1}}{1 + x}} \]
      9. +-commutative41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{-1 + x}}{1 + x}} \]
      10. +-commutative41.5%

        \[\leadsto \sqrt{\frac{-1 + x}{\color{blue}{x + 1}}} \]
    13. Simplified41.5%

      \[\leadsto \sqrt{\color{blue}{\frac{-1 + x}{x + 1}}} \]

    if 1.82000000000000009e93 < l < 4.20000000000000019e108

    1. Initial program 2.6%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified2.6%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(\frac{x + 1}{x + -1}, \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right), \ell \cdot \left(-\ell\right)\right)}}} \]
    3. Taylor expanded in l around inf 2.6%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\frac{t}{\ell} \cdot \sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}}\right)} \]
    4. Step-by-step derivation
      1. *-commutative2.6%

        \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}} \cdot \frac{t}{\ell}\right)} \]
      2. associate--l+20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\color{blue}{\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)}}} \cdot \frac{t}{\ell}\right) \]
      3. sub-neg20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      4. metadata-eval20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      5. +-commutative20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      6. sub-neg20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      7. metadata-eval20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      8. +-commutative20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
    5. Simplified20.2%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)}} \cdot \frac{t}{\ell}\right)} \]
    6. Taylor expanded in x around inf 100.0%

      \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{0.5 \cdot x}} \cdot \frac{t}{\ell}\right) \]
    7. Step-by-step derivation
      1. *-commutative100.0%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{x \cdot 0.5}} \cdot \frac{t}{\ell}\right) \]
    8. Simplified100.0%

      \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{x \cdot 0.5}} \cdot \frac{t}{\ell}\right) \]

    if 4.20000000000000019e108 < l < 4.8e178

    1. Initial program 9.5%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified9.6%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 18.1%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified18.1%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Taylor expanded in x around inf 18.1%

      \[\leadsto \color{blue}{1} \]

    if 4.8e178 < l

    1. Initial program 0.0%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified0.0%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(\frac{x + 1}{x + -1}, \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right), \ell \cdot \left(-\ell\right)\right)}}} \]
    3. Taylor expanded in l around inf 2.3%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\frac{t}{\ell} \cdot \sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}}\right)} \]
    4. Step-by-step derivation
      1. *-commutative2.3%

        \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}} \cdot \frac{t}{\ell}\right)} \]
      2. associate--l+22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\color{blue}{\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)}}} \cdot \frac{t}{\ell}\right) \]
      3. sub-neg22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      4. metadata-eval22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      5. +-commutative22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      6. sub-neg22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      7. metadata-eval22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      8. +-commutative22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
    5. Simplified22.7%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)}} \cdot \frac{t}{\ell}\right)} \]
    6. Taylor expanded in x around 0 66.2%

      \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{0.5 \cdot x - 0.5}} \cdot \frac{t}{\ell}\right) \]
    7. Taylor expanded in t around 0 66.2%

      \[\leadsto \color{blue}{\frac{t \cdot \sqrt{2}}{\ell} \cdot \sqrt{0.5 \cdot x - 0.5}} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification43.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\ell \leq 1.82 \cdot 10^{+93}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \mathbf{elif}\;\ell \leq 4.2 \cdot 10^{+108}:\\ \;\;\;\;\sqrt{2} \cdot \left(\sqrt{x \cdot 0.5} \cdot \frac{t}{\ell}\right)\\ \mathbf{elif}\;\ell \leq 4.8 \cdot 10^{+178}:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;\frac{t \cdot \sqrt{2}}{\ell} \cdot \sqrt{x \cdot 0.5 - 0.5}\\ \end{array} \]

Alternative 7: 78.6% accurate, 1.0× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ t_s \cdot \begin{array}{l} \mathbf{if}\;l_m \leq 1.95 \cdot 10^{+93}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \mathbf{elif}\;l_m \leq 1.2 \cdot 10^{+109} \lor \neg \left(l_m \leq 4.8 \cdot 10^{+171}\right):\\ \;\;\;\;\sqrt{2} \cdot \left(\sqrt{x \cdot 0.5} \cdot \frac{t_m}{l_m}\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
l_m = (fabs.f64 l)
t_m = (fabs.f64 t)
t_s = (copysign.f64 1 t)
(FPCore (t_s x l_m t_m)
 :precision binary64
 (*
  t_s
  (if (<= l_m 1.95e+93)
    (sqrt (/ (+ -1.0 x) (+ 1.0 x)))
    (if (or (<= l_m 1.2e+109) (not (<= l_m 4.8e+171)))
      (* (sqrt 2.0) (* (sqrt (* x 0.5)) (/ t_m l_m)))
      1.0))))
l_m = fabs(l);
t_m = fabs(t);
t_s = copysign(1.0, t);
double code(double t_s, double x, double l_m, double t_m) {
	double tmp;
	if (l_m <= 1.95e+93) {
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	} else if ((l_m <= 1.2e+109) || !(l_m <= 4.8e+171)) {
		tmp = sqrt(2.0) * (sqrt((x * 0.5)) * (t_m / l_m));
	} else {
		tmp = 1.0;
	}
	return t_s * tmp;
}
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0d0, t)
real(8) function code(t_s, x, l_m, t_m)
    real(8), intent (in) :: t_s
    real(8), intent (in) :: x
    real(8), intent (in) :: l_m
    real(8), intent (in) :: t_m
    real(8) :: tmp
    if (l_m <= 1.95d+93) then
        tmp = sqrt((((-1.0d0) + x) / (1.0d0 + x)))
    else if ((l_m <= 1.2d+109) .or. (.not. (l_m <= 4.8d+171))) then
        tmp = sqrt(2.0d0) * (sqrt((x * 0.5d0)) * (t_m / l_m))
    else
        tmp = 1.0d0
    end if
    code = t_s * tmp
end function
l_m = Math.abs(l);
t_m = Math.abs(t);
t_s = Math.copySign(1.0, t);
public static double code(double t_s, double x, double l_m, double t_m) {
	double tmp;
	if (l_m <= 1.95e+93) {
		tmp = Math.sqrt(((-1.0 + x) / (1.0 + x)));
	} else if ((l_m <= 1.2e+109) || !(l_m <= 4.8e+171)) {
		tmp = Math.sqrt(2.0) * (Math.sqrt((x * 0.5)) * (t_m / l_m));
	} else {
		tmp = 1.0;
	}
	return t_s * tmp;
}
l_m = math.fabs(l)
t_m = math.fabs(t)
t_s = math.copysign(1.0, t)
def code(t_s, x, l_m, t_m):
	tmp = 0
	if l_m <= 1.95e+93:
		tmp = math.sqrt(((-1.0 + x) / (1.0 + x)))
	elif (l_m <= 1.2e+109) or not (l_m <= 4.8e+171):
		tmp = math.sqrt(2.0) * (math.sqrt((x * 0.5)) * (t_m / l_m))
	else:
		tmp = 1.0
	return t_s * tmp
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0, t)
function code(t_s, x, l_m, t_m)
	tmp = 0.0
	if (l_m <= 1.95e+93)
		tmp = sqrt(Float64(Float64(-1.0 + x) / Float64(1.0 + x)));
	elseif ((l_m <= 1.2e+109) || !(l_m <= 4.8e+171))
		tmp = Float64(sqrt(2.0) * Float64(sqrt(Float64(x * 0.5)) * Float64(t_m / l_m)));
	else
		tmp = 1.0;
	end
	return Float64(t_s * tmp)
end
l_m = abs(l);
t_m = abs(t);
t_s = sign(t) * abs(1.0);
function tmp_2 = code(t_s, x, l_m, t_m)
	tmp = 0.0;
	if (l_m <= 1.95e+93)
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	elseif ((l_m <= 1.2e+109) || ~((l_m <= 4.8e+171)))
		tmp = sqrt(2.0) * (sqrt((x * 0.5)) * (t_m / l_m));
	else
		tmp = 1.0;
	end
	tmp_2 = t_s * tmp;
end
l_m = N[Abs[l], $MachinePrecision]
t_m = N[Abs[t], $MachinePrecision]
t_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[t$95$s_, x_, l$95$m_, t$95$m_] := N[(t$95$s * If[LessEqual[l$95$m, 1.95e+93], N[Sqrt[N[(N[(-1.0 + x), $MachinePrecision] / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], If[Or[LessEqual[l$95$m, 1.2e+109], N[Not[LessEqual[l$95$m, 4.8e+171]], $MachinePrecision]], N[(N[Sqrt[2.0], $MachinePrecision] * N[(N[Sqrt[N[(x * 0.5), $MachinePrecision]], $MachinePrecision] * N[(t$95$m / l$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 1.0]]), $MachinePrecision]
\begin{array}{l}
l_m = \left|\ell\right|
\\
t_m = \left|t\right|
\\
t_s = \mathsf{copysign}\left(1, t\right)

\\
t_s \cdot \begin{array}{l}
\mathbf{if}\;l_m \leq 1.95 \cdot 10^{+93}:\\
\;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\

\mathbf{elif}\;l_m \leq 1.2 \cdot 10^{+109} \lor \neg \left(l_m \leq 4.8 \cdot 10^{+171}\right):\\
\;\;\;\;\sqrt{2} \cdot \left(\sqrt{x \cdot 0.5} \cdot \frac{t_m}{l_m}\right)\\

\mathbf{else}:\\
\;\;\;\;1\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if l < 1.9500000000000001e93

    1. Initial program 34.2%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified34.2%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 41.5%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified41.5%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Step-by-step derivation
      1. sqrt-unprod41.5%

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      2. sqrt-undiv41.5%

        \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      3. +-commutative41.5%

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{\color{blue}{x + -1}}}} \]
    7. Applied egg-rr41.5%

      \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{x + -1}}}} \]
    8. Step-by-step derivation
      1. associate-/r*41.5%

        \[\leadsto \sqrt{\color{blue}{\frac{\frac{2}{2}}{\frac{x + 1}{x + -1}}}} \]
      2. metadata-eval41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{1}}{\frac{x + 1}{x + -1}}} \]
      3. +-commutative41.5%

        \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    9. Simplified41.5%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{x + 1}{-1 + x}}}} \]
    10. Step-by-step derivation
      1. expm1-log1p-u41.5%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)\right)}} \]
      2. expm1-udef41.5%

        \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)} - 1}} \]
      3. associate-/r/41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\color{blue}{\frac{1}{x + 1} \cdot \left(-1 + x\right)}\right)} - 1} \]
      4. +-commutative41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{1 + x}} \cdot \left(-1 + x\right)\right)} - 1} \]
      5. +-commutative41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \color{blue}{\left(x + -1\right)}\right)} - 1} \]
    11. Applied egg-rr41.5%

      \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)} - 1}} \]
    12. Step-by-step derivation
      1. expm1-def41.5%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)\right)}} \]
      2. expm1-log1p41.4%

        \[\leadsto \sqrt{\color{blue}{\frac{1}{1 + x} \cdot \left(x + -1\right)}} \]
      3. metadata-eval41.4%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \left(x + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg41.4%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \color{blue}{\left(x - 1\right)}} \]
      5. associate-*l/41.5%

        \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot \left(x - 1\right)}{1 + x}}} \]
      6. *-lft-identity41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{x - 1}}{1 + x}} \]
      7. sub-neg41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{x + \left(-1\right)}}{1 + x}} \]
      8. metadata-eval41.5%

        \[\leadsto \sqrt{\frac{x + \color{blue}{-1}}{1 + x}} \]
      9. +-commutative41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{-1 + x}}{1 + x}} \]
      10. +-commutative41.5%

        \[\leadsto \sqrt{\frac{-1 + x}{\color{blue}{x + 1}}} \]
    13. Simplified41.5%

      \[\leadsto \sqrt{\color{blue}{\frac{-1 + x}{x + 1}}} \]

    if 1.9500000000000001e93 < l < 1.19999999999999994e109 or 4.79999999999999995e171 < l

    1. Initial program 0.3%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified0.3%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(\frac{x + 1}{x + -1}, \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right), \ell \cdot \left(-\ell\right)\right)}}} \]
    3. Taylor expanded in l around inf 2.3%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\frac{t}{\ell} \cdot \sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}}\right)} \]
    4. Step-by-step derivation
      1. *-commutative2.3%

        \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}} \cdot \frac{t}{\ell}\right)} \]
      2. associate--l+22.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\color{blue}{\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)}}} \cdot \frac{t}{\ell}\right) \]
      3. sub-neg22.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      4. metadata-eval22.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      5. +-commutative22.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      6. sub-neg22.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      7. metadata-eval22.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      8. +-commutative22.3%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
    5. Simplified22.3%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)}} \cdot \frac{t}{\ell}\right)} \]
    6. Taylor expanded in x around inf 70.6%

      \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{0.5 \cdot x}} \cdot \frac{t}{\ell}\right) \]
    7. Step-by-step derivation
      1. *-commutative70.6%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{x \cdot 0.5}} \cdot \frac{t}{\ell}\right) \]
    8. Simplified70.6%

      \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{x \cdot 0.5}} \cdot \frac{t}{\ell}\right) \]

    if 1.19999999999999994e109 < l < 4.79999999999999995e171

    1. Initial program 9.5%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified9.6%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 18.1%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified18.1%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Taylor expanded in x around inf 18.1%

      \[\leadsto \color{blue}{1} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification43.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\ell \leq 1.95 \cdot 10^{+93}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \mathbf{elif}\;\ell \leq 1.2 \cdot 10^{+109} \lor \neg \left(\ell \leq 4.8 \cdot 10^{+171}\right):\\ \;\;\;\;\sqrt{2} \cdot \left(\sqrt{x \cdot 0.5} \cdot \frac{t}{\ell}\right)\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]

Alternative 8: 78.7% accurate, 1.0× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ t_s \cdot \begin{array}{l} \mathbf{if}\;l_m \leq 4 \cdot 10^{+93}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \mathbf{elif}\;l_m \leq 1.1 \cdot 10^{+109}:\\ \;\;\;\;\sqrt{2} \cdot \left(\sqrt{x \cdot 0.5} \cdot \frac{t_m}{l_m}\right)\\ \mathbf{elif}\;l_m \leq 1.26 \cdot 10^{+169}:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;\frac{t_m}{l_m} \cdot \sqrt{2 \cdot \mathsf{fma}\left(x, 0.5, -0.5\right)}\\ \end{array} \end{array} \]
l_m = (fabs.f64 l)
t_m = (fabs.f64 t)
t_s = (copysign.f64 1 t)
(FPCore (t_s x l_m t_m)
 :precision binary64
 (*
  t_s
  (if (<= l_m 4e+93)
    (sqrt (/ (+ -1.0 x) (+ 1.0 x)))
    (if (<= l_m 1.1e+109)
      (* (sqrt 2.0) (* (sqrt (* x 0.5)) (/ t_m l_m)))
      (if (<= l_m 1.26e+169)
        1.0
        (* (/ t_m l_m) (sqrt (* 2.0 (fma x 0.5 -0.5)))))))))
l_m = fabs(l);
t_m = fabs(t);
t_s = copysign(1.0, t);
double code(double t_s, double x, double l_m, double t_m) {
	double tmp;
	if (l_m <= 4e+93) {
		tmp = sqrt(((-1.0 + x) / (1.0 + x)));
	} else if (l_m <= 1.1e+109) {
		tmp = sqrt(2.0) * (sqrt((x * 0.5)) * (t_m / l_m));
	} else if (l_m <= 1.26e+169) {
		tmp = 1.0;
	} else {
		tmp = (t_m / l_m) * sqrt((2.0 * fma(x, 0.5, -0.5)));
	}
	return t_s * tmp;
}
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0, t)
function code(t_s, x, l_m, t_m)
	tmp = 0.0
	if (l_m <= 4e+93)
		tmp = sqrt(Float64(Float64(-1.0 + x) / Float64(1.0 + x)));
	elseif (l_m <= 1.1e+109)
		tmp = Float64(sqrt(2.0) * Float64(sqrt(Float64(x * 0.5)) * Float64(t_m / l_m)));
	elseif (l_m <= 1.26e+169)
		tmp = 1.0;
	else
		tmp = Float64(Float64(t_m / l_m) * sqrt(Float64(2.0 * fma(x, 0.5, -0.5))));
	end
	return Float64(t_s * tmp)
end
l_m = N[Abs[l], $MachinePrecision]
t_m = N[Abs[t], $MachinePrecision]
t_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[t$95$s_, x_, l$95$m_, t$95$m_] := N[(t$95$s * If[LessEqual[l$95$m, 4e+93], N[Sqrt[N[(N[(-1.0 + x), $MachinePrecision] / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], If[LessEqual[l$95$m, 1.1e+109], N[(N[Sqrt[2.0], $MachinePrecision] * N[(N[Sqrt[N[(x * 0.5), $MachinePrecision]], $MachinePrecision] * N[(t$95$m / l$95$m), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[l$95$m, 1.26e+169], 1.0, N[(N[(t$95$m / l$95$m), $MachinePrecision] * N[Sqrt[N[(2.0 * N[(x * 0.5 + -0.5), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]), $MachinePrecision]
\begin{array}{l}
l_m = \left|\ell\right|
\\
t_m = \left|t\right|
\\
t_s = \mathsf{copysign}\left(1, t\right)

\\
t_s \cdot \begin{array}{l}
\mathbf{if}\;l_m \leq 4 \cdot 10^{+93}:\\
\;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\

\mathbf{elif}\;l_m \leq 1.1 \cdot 10^{+109}:\\
\;\;\;\;\sqrt{2} \cdot \left(\sqrt{x \cdot 0.5} \cdot \frac{t_m}{l_m}\right)\\

\mathbf{elif}\;l_m \leq 1.26 \cdot 10^{+169}:\\
\;\;\;\;1\\

\mathbf{else}:\\
\;\;\;\;\frac{t_m}{l_m} \cdot \sqrt{2 \cdot \mathsf{fma}\left(x, 0.5, -0.5\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if l < 4.00000000000000017e93

    1. Initial program 34.2%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified34.2%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 41.5%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative41.5%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified41.5%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Step-by-step derivation
      1. sqrt-unprod41.5%

        \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      2. sqrt-undiv41.5%

        \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{-1 + x}}}} \]
      3. +-commutative41.5%

        \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{\color{blue}{x + -1}}}} \]
    7. Applied egg-rr41.5%

      \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{x + -1}}}} \]
    8. Step-by-step derivation
      1. associate-/r*41.5%

        \[\leadsto \sqrt{\color{blue}{\frac{\frac{2}{2}}{\frac{x + 1}{x + -1}}}} \]
      2. metadata-eval41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{1}}{\frac{x + 1}{x + -1}}} \]
      3. +-commutative41.5%

        \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    9. Simplified41.5%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{x + 1}{-1 + x}}}} \]
    10. Step-by-step derivation
      1. expm1-log1p-u41.5%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)\right)}} \]
      2. expm1-udef41.5%

        \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)} - 1}} \]
      3. associate-/r/41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\color{blue}{\frac{1}{x + 1} \cdot \left(-1 + x\right)}\right)} - 1} \]
      4. +-commutative41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{1 + x}} \cdot \left(-1 + x\right)\right)} - 1} \]
      5. +-commutative41.5%

        \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \color{blue}{\left(x + -1\right)}\right)} - 1} \]
    11. Applied egg-rr41.5%

      \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)} - 1}} \]
    12. Step-by-step derivation
      1. expm1-def41.5%

        \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)\right)}} \]
      2. expm1-log1p41.4%

        \[\leadsto \sqrt{\color{blue}{\frac{1}{1 + x} \cdot \left(x + -1\right)}} \]
      3. metadata-eval41.4%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \left(x + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg41.4%

        \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \color{blue}{\left(x - 1\right)}} \]
      5. associate-*l/41.5%

        \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot \left(x - 1\right)}{1 + x}}} \]
      6. *-lft-identity41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{x - 1}}{1 + x}} \]
      7. sub-neg41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{x + \left(-1\right)}}{1 + x}} \]
      8. metadata-eval41.5%

        \[\leadsto \sqrt{\frac{x + \color{blue}{-1}}{1 + x}} \]
      9. +-commutative41.5%

        \[\leadsto \sqrt{\frac{\color{blue}{-1 + x}}{1 + x}} \]
      10. +-commutative41.5%

        \[\leadsto \sqrt{\frac{-1 + x}{\color{blue}{x + 1}}} \]
    13. Simplified41.5%

      \[\leadsto \sqrt{\color{blue}{\frac{-1 + x}{x + 1}}} \]

    if 4.00000000000000017e93 < l < 1.1e109

    1. Initial program 2.6%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified2.6%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(\frac{x + 1}{x + -1}, \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right), \ell \cdot \left(-\ell\right)\right)}}} \]
    3. Taylor expanded in l around inf 2.6%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\frac{t}{\ell} \cdot \sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}}\right)} \]
    4. Step-by-step derivation
      1. *-commutative2.6%

        \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}} \cdot \frac{t}{\ell}\right)} \]
      2. associate--l+20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\color{blue}{\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)}}} \cdot \frac{t}{\ell}\right) \]
      3. sub-neg20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      4. metadata-eval20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      5. +-commutative20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      6. sub-neg20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      7. metadata-eval20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      8. +-commutative20.2%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
    5. Simplified20.2%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)}} \cdot \frac{t}{\ell}\right)} \]
    6. Taylor expanded in x around inf 100.0%

      \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{0.5 \cdot x}} \cdot \frac{t}{\ell}\right) \]
    7. Step-by-step derivation
      1. *-commutative100.0%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{x \cdot 0.5}} \cdot \frac{t}{\ell}\right) \]
    8. Simplified100.0%

      \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{x \cdot 0.5}} \cdot \frac{t}{\ell}\right) \]

    if 1.1e109 < l < 1.2599999999999999e169

    1. Initial program 9.5%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified9.6%

      \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
    3. Taylor expanded in l around 0 18.1%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
    4. Step-by-step derivation
      1. +-commutative18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
      2. sub-neg18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
      3. metadata-eval18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
      4. +-commutative18.1%

        \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
    5. Simplified18.1%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
    6. Taylor expanded in x around inf 18.1%

      \[\leadsto \color{blue}{1} \]

    if 1.2599999999999999e169 < l

    1. Initial program 0.0%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified0.0%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(\frac{x + 1}{x + -1}, \mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right), \ell \cdot \left(-\ell\right)\right)}}} \]
    3. Taylor expanded in l around inf 2.3%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\frac{t}{\ell} \cdot \sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}}\right)} \]
    4. Step-by-step derivation
      1. *-commutative2.3%

        \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1}} \cdot \frac{t}{\ell}\right)} \]
      2. associate--l+22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\color{blue}{\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)}}} \cdot \frac{t}{\ell}\right) \]
      3. sub-neg22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      4. metadata-eval22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      5. +-commutative22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      6. sub-neg22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      7. metadata-eval22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
      8. +-commutative22.7%

        \[\leadsto \sqrt{2} \cdot \left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)}} \cdot \frac{t}{\ell}\right) \]
    5. Simplified22.7%

      \[\leadsto \sqrt{2} \cdot \color{blue}{\left(\sqrt{\frac{1}{\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)}} \cdot \frac{t}{\ell}\right)} \]
    6. Taylor expanded in x around 0 66.2%

      \[\leadsto \sqrt{2} \cdot \left(\sqrt{\color{blue}{0.5 \cdot x - 0.5}} \cdot \frac{t}{\ell}\right) \]
    7. Step-by-step derivation
      1. expm1-log1p-u65.5%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{2} \cdot \left(\sqrt{0.5 \cdot x - 0.5} \cdot \frac{t}{\ell}\right)\right)\right)} \]
      2. expm1-udef13.3%

        \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\sqrt{2} \cdot \left(\sqrt{0.5 \cdot x - 0.5} \cdot \frac{t}{\ell}\right)\right)} - 1} \]
      3. associate-*r*13.3%

        \[\leadsto e^{\mathsf{log1p}\left(\color{blue}{\left(\sqrt{2} \cdot \sqrt{0.5 \cdot x - 0.5}\right) \cdot \frac{t}{\ell}}\right)} - 1 \]
      4. sqrt-unprod13.3%

        \[\leadsto e^{\mathsf{log1p}\left(\color{blue}{\sqrt{2 \cdot \left(0.5 \cdot x - 0.5\right)}} \cdot \frac{t}{\ell}\right)} - 1 \]
      5. *-commutative13.3%

        \[\leadsto e^{\mathsf{log1p}\left(\sqrt{2 \cdot \left(\color{blue}{x \cdot 0.5} - 0.5\right)} \cdot \frac{t}{\ell}\right)} - 1 \]
      6. fma-neg13.3%

        \[\leadsto e^{\mathsf{log1p}\left(\sqrt{2 \cdot \color{blue}{\mathsf{fma}\left(x, 0.5, -0.5\right)}} \cdot \frac{t}{\ell}\right)} - 1 \]
      7. metadata-eval13.3%

        \[\leadsto e^{\mathsf{log1p}\left(\sqrt{2 \cdot \mathsf{fma}\left(x, 0.5, \color{blue}{-0.5}\right)} \cdot \frac{t}{\ell}\right)} - 1 \]
    8. Applied egg-rr13.3%

      \[\leadsto \color{blue}{e^{\mathsf{log1p}\left(\sqrt{2 \cdot \mathsf{fma}\left(x, 0.5, -0.5\right)} \cdot \frac{t}{\ell}\right)} - 1} \]
    9. Step-by-step derivation
      1. expm1-def65.5%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{2 \cdot \mathsf{fma}\left(x, 0.5, -0.5\right)} \cdot \frac{t}{\ell}\right)\right)} \]
      2. expm1-log1p66.3%

        \[\leadsto \color{blue}{\sqrt{2 \cdot \mathsf{fma}\left(x, 0.5, -0.5\right)} \cdot \frac{t}{\ell}} \]
      3. *-commutative66.3%

        \[\leadsto \color{blue}{\frac{t}{\ell} \cdot \sqrt{2 \cdot \mathsf{fma}\left(x, 0.5, -0.5\right)}} \]
    10. Simplified66.3%

      \[\leadsto \color{blue}{\frac{t}{\ell} \cdot \sqrt{2 \cdot \mathsf{fma}\left(x, 0.5, -0.5\right)}} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification43.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\ell \leq 4 \cdot 10^{+93}:\\ \;\;\;\;\sqrt{\frac{-1 + x}{1 + x}}\\ \mathbf{elif}\;\ell \leq 1.1 \cdot 10^{+109}:\\ \;\;\;\;\sqrt{2} \cdot \left(\sqrt{x \cdot 0.5} \cdot \frac{t}{\ell}\right)\\ \mathbf{elif}\;\ell \leq 1.26 \cdot 10^{+169}:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;\frac{t}{\ell} \cdot \sqrt{2 \cdot \mathsf{fma}\left(x, 0.5, -0.5\right)}\\ \end{array} \]

Alternative 9: 77.0% accurate, 2.1× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ t_s \cdot \sqrt{\frac{-1 + x}{1 + x}} \end{array} \]
l_m = (fabs.f64 l)
t_m = (fabs.f64 t)
t_s = (copysign.f64 1 t)
(FPCore (t_s x l_m t_m)
 :precision binary64
 (* t_s (sqrt (/ (+ -1.0 x) (+ 1.0 x)))))
l_m = fabs(l);
t_m = fabs(t);
t_s = copysign(1.0, t);
double code(double t_s, double x, double l_m, double t_m) {
	return t_s * sqrt(((-1.0 + x) / (1.0 + x)));
}
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0d0, t)
real(8) function code(t_s, x, l_m, t_m)
    real(8), intent (in) :: t_s
    real(8), intent (in) :: x
    real(8), intent (in) :: l_m
    real(8), intent (in) :: t_m
    code = t_s * sqrt((((-1.0d0) + x) / (1.0d0 + x)))
end function
l_m = Math.abs(l);
t_m = Math.abs(t);
t_s = Math.copySign(1.0, t);
public static double code(double t_s, double x, double l_m, double t_m) {
	return t_s * Math.sqrt(((-1.0 + x) / (1.0 + x)));
}
l_m = math.fabs(l)
t_m = math.fabs(t)
t_s = math.copysign(1.0, t)
def code(t_s, x, l_m, t_m):
	return t_s * math.sqrt(((-1.0 + x) / (1.0 + x)))
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0, t)
function code(t_s, x, l_m, t_m)
	return Float64(t_s * sqrt(Float64(Float64(-1.0 + x) / Float64(1.0 + x))))
end
l_m = abs(l);
t_m = abs(t);
t_s = sign(t) * abs(1.0);
function tmp = code(t_s, x, l_m, t_m)
	tmp = t_s * sqrt(((-1.0 + x) / (1.0 + x)));
end
l_m = N[Abs[l], $MachinePrecision]
t_m = N[Abs[t], $MachinePrecision]
t_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[t$95$s_, x_, l$95$m_, t$95$m_] := N[(t$95$s * N[Sqrt[N[(N[(-1.0 + x), $MachinePrecision] / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
l_m = \left|\ell\right|
\\
t_m = \left|t\right|
\\
t_s = \mathsf{copysign}\left(1, t\right)

\\
t_s \cdot \sqrt{\frac{-1 + x}{1 + x}}
\end{array}
Derivation
  1. Initial program 29.9%

    \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
  2. Simplified29.9%

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
  3. Taylor expanded in l around 0 38.0%

    \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
  4. Step-by-step derivation
    1. +-commutative38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
    2. sub-neg38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
    3. metadata-eval38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
    4. +-commutative38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
  5. Simplified38.0%

    \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
  6. Step-by-step derivation
    1. sqrt-unprod38.0%

      \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2 \cdot \frac{x + 1}{-1 + x}}}} \]
    2. sqrt-undiv38.0%

      \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{-1 + x}}}} \]
    3. +-commutative38.0%

      \[\leadsto \sqrt{\frac{2}{2 \cdot \frac{x + 1}{\color{blue}{x + -1}}}} \]
  7. Applied egg-rr38.0%

    \[\leadsto \color{blue}{\sqrt{\frac{2}{2 \cdot \frac{x + 1}{x + -1}}}} \]
  8. Step-by-step derivation
    1. associate-/r*38.0%

      \[\leadsto \sqrt{\color{blue}{\frac{\frac{2}{2}}{\frac{x + 1}{x + -1}}}} \]
    2. metadata-eval38.0%

      \[\leadsto \sqrt{\frac{\color{blue}{1}}{\frac{x + 1}{x + -1}}} \]
    3. +-commutative38.0%

      \[\leadsto \sqrt{\frac{1}{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
  9. Simplified38.0%

    \[\leadsto \color{blue}{\sqrt{\frac{1}{\frac{x + 1}{-1 + x}}}} \]
  10. Step-by-step derivation
    1. expm1-log1p-u38.0%

      \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)\right)}} \]
    2. expm1-udef38.0%

      \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{\frac{x + 1}{-1 + x}}\right)} - 1}} \]
    3. associate-/r/38.0%

      \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\color{blue}{\frac{1}{x + 1} \cdot \left(-1 + x\right)}\right)} - 1} \]
    4. +-commutative38.0%

      \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{\color{blue}{1 + x}} \cdot \left(-1 + x\right)\right)} - 1} \]
    5. +-commutative38.0%

      \[\leadsto \sqrt{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \color{blue}{\left(x + -1\right)}\right)} - 1} \]
  11. Applied egg-rr38.0%

    \[\leadsto \sqrt{\color{blue}{e^{\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)} - 1}} \]
  12. Step-by-step derivation
    1. expm1-def38.0%

      \[\leadsto \sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{1}{1 + x} \cdot \left(x + -1\right)\right)\right)}} \]
    2. expm1-log1p37.9%

      \[\leadsto \sqrt{\color{blue}{\frac{1}{1 + x} \cdot \left(x + -1\right)}} \]
    3. metadata-eval37.9%

      \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \left(x + \color{blue}{\left(-1\right)}\right)} \]
    4. sub-neg37.9%

      \[\leadsto \sqrt{\frac{1}{1 + x} \cdot \color{blue}{\left(x - 1\right)}} \]
    5. associate-*l/38.0%

      \[\leadsto \sqrt{\color{blue}{\frac{1 \cdot \left(x - 1\right)}{1 + x}}} \]
    6. *-lft-identity38.0%

      \[\leadsto \sqrt{\frac{\color{blue}{x - 1}}{1 + x}} \]
    7. sub-neg38.0%

      \[\leadsto \sqrt{\frac{\color{blue}{x + \left(-1\right)}}{1 + x}} \]
    8. metadata-eval38.0%

      \[\leadsto \sqrt{\frac{x + \color{blue}{-1}}{1 + x}} \]
    9. +-commutative38.0%

      \[\leadsto \sqrt{\frac{\color{blue}{-1 + x}}{1 + x}} \]
    10. +-commutative38.0%

      \[\leadsto \sqrt{\frac{-1 + x}{\color{blue}{x + 1}}} \]
  13. Simplified38.0%

    \[\leadsto \sqrt{\color{blue}{\frac{-1 + x}{x + 1}}} \]
  14. Final simplification38.0%

    \[\leadsto \sqrt{\frac{-1 + x}{1 + x}} \]

Alternative 10: 76.4% accurate, 45.0× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ t_s \cdot \left(1 + \frac{-1}{x}\right) \end{array} \]
l_m = (fabs.f64 l)
t_m = (fabs.f64 t)
t_s = (copysign.f64 1 t)
(FPCore (t_s x l_m t_m) :precision binary64 (* t_s (+ 1.0 (/ -1.0 x))))
l_m = fabs(l);
t_m = fabs(t);
t_s = copysign(1.0, t);
double code(double t_s, double x, double l_m, double t_m) {
	return t_s * (1.0 + (-1.0 / x));
}
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0d0, t)
real(8) function code(t_s, x, l_m, t_m)
    real(8), intent (in) :: t_s
    real(8), intent (in) :: x
    real(8), intent (in) :: l_m
    real(8), intent (in) :: t_m
    code = t_s * (1.0d0 + ((-1.0d0) / x))
end function
l_m = Math.abs(l);
t_m = Math.abs(t);
t_s = Math.copySign(1.0, t);
public static double code(double t_s, double x, double l_m, double t_m) {
	return t_s * (1.0 + (-1.0 / x));
}
l_m = math.fabs(l)
t_m = math.fabs(t)
t_s = math.copysign(1.0, t)
def code(t_s, x, l_m, t_m):
	return t_s * (1.0 + (-1.0 / x))
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0, t)
function code(t_s, x, l_m, t_m)
	return Float64(t_s * Float64(1.0 + Float64(-1.0 / x)))
end
l_m = abs(l);
t_m = abs(t);
t_s = sign(t) * abs(1.0);
function tmp = code(t_s, x, l_m, t_m)
	tmp = t_s * (1.0 + (-1.0 / x));
end
l_m = N[Abs[l], $MachinePrecision]
t_m = N[Abs[t], $MachinePrecision]
t_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[t$95$s_, x_, l$95$m_, t$95$m_] := N[(t$95$s * N[(1.0 + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
l_m = \left|\ell\right|
\\
t_m = \left|t\right|
\\
t_s = \mathsf{copysign}\left(1, t\right)

\\
t_s \cdot \left(1 + \frac{-1}{x}\right)
\end{array}
Derivation
  1. Initial program 29.9%

    \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
  2. Simplified29.9%

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
  3. Taylor expanded in l around 0 38.0%

    \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
  4. Step-by-step derivation
    1. +-commutative38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
    2. sub-neg38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
    3. metadata-eval38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
    4. +-commutative38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
  5. Simplified38.0%

    \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
  6. Taylor expanded in x around inf 37.9%

    \[\leadsto \color{blue}{1 - \frac{1}{x}} \]
  7. Final simplification37.9%

    \[\leadsto 1 + \frac{-1}{x} \]

Alternative 11: 75.8% accurate, 225.0× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ t_s \cdot 1 \end{array} \]
l_m = (fabs.f64 l)
t_m = (fabs.f64 t)
t_s = (copysign.f64 1 t)
(FPCore (t_s x l_m t_m) :precision binary64 (* t_s 1.0))
l_m = fabs(l);
t_m = fabs(t);
t_s = copysign(1.0, t);
double code(double t_s, double x, double l_m, double t_m) {
	return t_s * 1.0;
}
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0d0, t)
real(8) function code(t_s, x, l_m, t_m)
    real(8), intent (in) :: t_s
    real(8), intent (in) :: x
    real(8), intent (in) :: l_m
    real(8), intent (in) :: t_m
    code = t_s * 1.0d0
end function
l_m = Math.abs(l);
t_m = Math.abs(t);
t_s = Math.copySign(1.0, t);
public static double code(double t_s, double x, double l_m, double t_m) {
	return t_s * 1.0;
}
l_m = math.fabs(l)
t_m = math.fabs(t)
t_s = math.copysign(1.0, t)
def code(t_s, x, l_m, t_m):
	return t_s * 1.0
l_m = abs(l)
t_m = abs(t)
t_s = copysign(1.0, t)
function code(t_s, x, l_m, t_m)
	return Float64(t_s * 1.0)
end
l_m = abs(l);
t_m = abs(t);
t_s = sign(t) * abs(1.0);
function tmp = code(t_s, x, l_m, t_m)
	tmp = t_s * 1.0;
end
l_m = N[Abs[l], $MachinePrecision]
t_m = N[Abs[t], $MachinePrecision]
t_s = N[With[{TMP1 = Abs[1.0], TMP2 = Sign[t]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision]
code[t$95$s_, x_, l$95$m_, t$95$m_] := N[(t$95$s * 1.0), $MachinePrecision]
\begin{array}{l}
l_m = \left|\ell\right|
\\
t_m = \left|t\right|
\\
t_s = \mathsf{copysign}\left(1, t\right)

\\
t_s \cdot 1
\end{array}
Derivation
  1. Initial program 29.9%

    \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
  2. Simplified29.9%

    \[\leadsto \color{blue}{\frac{\sqrt{2}}{\frac{\sqrt{\frac{x + 1}{x + -1} \cdot \mathsf{fma}\left(\ell, \ell, 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}}{t}}} \]
  3. Taylor expanded in l around 0 38.0%

    \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{1 + x}{x - 1}}}} \]
  4. Step-by-step derivation
    1. +-commutative38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{\color{blue}{x + 1}}{x - 1}}} \]
    2. sub-neg38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{x + \left(-1\right)}}}} \]
    3. metadata-eval38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{x + \color{blue}{-1}}}} \]
    4. +-commutative38.0%

      \[\leadsto \frac{\sqrt{2}}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{\color{blue}{-1 + x}}}} \]
  5. Simplified38.0%

    \[\leadsto \frac{\sqrt{2}}{\color{blue}{\sqrt{2} \cdot \sqrt{\frac{x + 1}{-1 + x}}}} \]
  6. Taylor expanded in x around inf 37.3%

    \[\leadsto \color{blue}{1} \]
  7. Final simplification37.3%

    \[\leadsto 1 \]

Reproduce

?
herbie shell --seed 2023322 
(FPCore (x l t)
  :name "Toniolo and Linder, Equation (7)"
  :precision binary64
  (/ (* (sqrt 2.0) t) (sqrt (- (* (/ (+ x 1.0) (- x 1.0)) (+ (* l l) (* 2.0 (* t t)))) (* l l)))))