Toniolo and Linder, Equation (7)

Percentage Accurate: 32.9% → 84.6%
Time: 20.5s
Alternatives: 7
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 7 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: 32.9% 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: 84.6% accurate, 0.4× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ t\_s \cdot \begin{array}{l} \mathbf{if}\;t\_m \leq 2.7 \cdot 10^{-211}:\\ \;\;\;\;t\_m \cdot \frac{\sqrt{x}}{l\_m}\\ \mathbf{elif}\;t\_m \leq 9.5 \cdot 10^{-162}:\\ \;\;\;\;1\\ \mathbf{elif}\;t\_m \leq 6.3 \cdot 10^{+86}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t\_m}{\sqrt{\mathsf{fma}\left(2, {t\_m}^{2} \cdot \frac{x + 1}{x + -1}, 2 \cdot \frac{{l\_m}^{2}}{x}\right)}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{x + -1}{x + 1}}\\ \end{array} \end{array} \]
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 (<= t_m 2.7e-211)
    (* t_m (/ (sqrt x) l_m))
    (if (<= t_m 9.5e-162)
      1.0
      (if (<= t_m 6.3e+86)
        (*
         (sqrt 2.0)
         (/
          t_m
          (sqrt
           (fma
            2.0
            (* (pow t_m 2.0) (/ (+ x 1.0) (+ x -1.0)))
            (* 2.0 (/ (pow l_m 2.0) x))))))
        (sqrt (/ (+ x -1.0) (+ x 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 (t_m <= 2.7e-211) {
		tmp = t_m * (sqrt(x) / l_m);
	} else if (t_m <= 9.5e-162) {
		tmp = 1.0;
	} else if (t_m <= 6.3e+86) {
		tmp = sqrt(2.0) * (t_m / sqrt(fma(2.0, (pow(t_m, 2.0) * ((x + 1.0) / (x + -1.0))), (2.0 * (pow(l_m, 2.0) / x)))));
	} else {
		tmp = sqrt(((x + -1.0) / (x + 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 (t_m <= 2.7e-211)
		tmp = Float64(t_m * Float64(sqrt(x) / l_m));
	elseif (t_m <= 9.5e-162)
		tmp = 1.0;
	elseif (t_m <= 6.3e+86)
		tmp = Float64(sqrt(2.0) * Float64(t_m / sqrt(fma(2.0, Float64((t_m ^ 2.0) * Float64(Float64(x + 1.0) / Float64(x + -1.0))), Float64(2.0 * Float64((l_m ^ 2.0) / x))))));
	else
		tmp = sqrt(Float64(Float64(x + -1.0) / Float64(x + 1.0)));
	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[t$95$m, 2.7e-211], N[(t$95$m * N[(N[Sqrt[x], $MachinePrecision] / l$95$m), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$m, 9.5e-162], 1.0, If[LessEqual[t$95$m, 6.3e+86], N[(N[Sqrt[2.0], $MachinePrecision] * N[(t$95$m / N[Sqrt[N[(2.0 * N[(N[Power[t$95$m, 2.0], $MachinePrecision] * N[(N[(x + 1.0), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(2.0 * N[(N[Power[l$95$m, 2.0], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[(x + -1.0), $MachinePrecision] / N[(x + 1.0), $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}\;t\_m \leq 2.7 \cdot 10^{-211}:\\
\;\;\;\;t\_m \cdot \frac{\sqrt{x}}{l\_m}\\

\mathbf{elif}\;t\_m \leq 9.5 \cdot 10^{-162}:\\
\;\;\;\;1\\

\mathbf{elif}\;t\_m \leq 6.3 \cdot 10^{+86}:\\
\;\;\;\;\sqrt{2} \cdot \frac{t\_m}{\sqrt{\mathsf{fma}\left(2, {t\_m}^{2} \cdot \frac{x + 1}{x + -1}, 2 \cdot \frac{{l\_m}^{2}}{x}\right)}}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if t < 2.6999999999999999e-211

    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. Simplified24.4%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Taylor expanded in t around 0 2.1%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \color{blue}{\frac{{\ell}^{2}}{x - 1}}, -\ell \cdot \ell\right)}} \]
    5. Taylor expanded in x around inf 19.1%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{\frac{{\ell}^{2} - -1 \cdot {\ell}^{2}}{x}}}} \]
    6. Step-by-step derivation
      1. unpow219.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\color{blue}{\ell \cdot \ell} - -1 \cdot {\ell}^{2}}{x}}} \]
      2. fma-neg19.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\color{blue}{\mathsf{fma}\left(\ell, \ell, --1 \cdot {\ell}^{2}\right)}}{x}}} \]
      3. neg-mul-119.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\mathsf{fma}\left(\ell, \ell, -\color{blue}{\left(-{\ell}^{2}\right)}\right)}{x}}} \]
      4. remove-double-neg19.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\mathsf{fma}\left(\ell, \ell, \color{blue}{{\ell}^{2}}\right)}{x}}} \]
    7. Simplified19.1%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{\frac{\mathsf{fma}\left(\ell, \ell, {\ell}^{2}\right)}{x}}}} \]
    8. Taylor expanded in t around 0 18.5%

      \[\leadsto \color{blue}{\frac{t}{\ell} \cdot \sqrt{x}} \]
    9. Step-by-step derivation
      1. associate-*l/18.5%

        \[\leadsto \color{blue}{\frac{t \cdot \sqrt{x}}{\ell}} \]
      2. associate-/l*18.5%

        \[\leadsto \color{blue}{t \cdot \frac{\sqrt{x}}{\ell}} \]
    10. Simplified18.5%

      \[\leadsto \color{blue}{t \cdot \frac{\sqrt{x}}{\ell}} \]

    if 2.6999999999999999e-211 < t < 9.5000000000000004e-162

    1. Initial program 6.5%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified2.5%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Applied egg-rr48.1%

      \[\leadsto \color{blue}{\frac{1}{\frac{\mathsf{hypot}\left(\mathsf{hypot}\left(\ell, t \cdot \sqrt{2}\right) \cdot \sqrt{\frac{x + 1}{x + -1}}, \ell\right)}{t \cdot \sqrt{2}}}} \]
    5. Taylor expanded in l around 0 86.4%

      \[\leadsto \color{blue}{\sqrt{\frac{x - 1}{1 + x}}} \]
    6. Taylor expanded in x around inf 86.4%

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

    if 9.5000000000000004e-162 < t < 6.30000000000000023e86

    1. Initial program 62.7%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified49.8%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Taylor expanded in l around 0 63.1%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{2 \cdot \frac{{t}^{2} \cdot \left(1 + x\right)}{x - 1} + {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)}}} \]
    5. Step-by-step derivation
      1. fma-define63.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{\mathsf{fma}\left(2, \frac{{t}^{2} \cdot \left(1 + x\right)}{x - 1}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}}} \]
      2. +-commutative63.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, \frac{{t}^{2} \cdot \color{blue}{\left(x + 1\right)}}{x - 1}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}} \]
      3. associate-*r/81.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, \color{blue}{{t}^{2} \cdot \frac{x + 1}{x - 1}}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}} \]
      4. sub-neg81.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{\color{blue}{x + \left(-1\right)}}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}} \]
      5. metadata-eval81.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{x + \color{blue}{-1}}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}} \]
      6. +-commutative81.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{\color{blue}{-1 + x}}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}} \]
      7. associate--l+82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \color{blue}{\left(\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)\right)}\right)}} \]
      8. sub-neg82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)\right)\right)}} \]
      9. metadata-eval82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)\right)\right)}} \]
      10. +-commutative82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)\right)\right)}} \]
      11. sub-neg82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)\right)\right)}} \]
      12. metadata-eval82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)\right)\right)}} \]
      13. +-commutative82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)\right)\right)}} \]
    6. Simplified82.5%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)\right)\right)}}} \]
    7. Taylor expanded in x around inf 87.8%

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

    if 6.30000000000000023e86 < t

    1. Initial program 32.4%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified32.2%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Applied egg-rr82.3%

      \[\leadsto \color{blue}{\frac{1}{\frac{\mathsf{hypot}\left(\mathsf{hypot}\left(\ell, t \cdot \sqrt{2}\right) \cdot \sqrt{\frac{x + 1}{x + -1}}, \ell\right)}{t \cdot \sqrt{2}}}} \]
    5. Taylor expanded in l around 0 95.2%

      \[\leadsto \color{blue}{\sqrt{\frac{x - 1}{1 + x}}} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification50.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 2.7 \cdot 10^{-211}:\\ \;\;\;\;t \cdot \frac{\sqrt{x}}{\ell}\\ \mathbf{elif}\;t \leq 9.5 \cdot 10^{-162}:\\ \;\;\;\;1\\ \mathbf{elif}\;t \leq 6.3 \cdot 10^{+86}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{x + -1}, 2 \cdot \frac{{\ell}^{2}}{x}\right)}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{x + -1}{x + 1}}\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 84.4% accurate, 0.2× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ \begin{array}{l} t_2 := 2 \cdot {t\_m}^{2}\\ t_3 := {l\_m}^{2} + t\_2\\ t\_s \cdot \begin{array}{l} \mathbf{if}\;t\_m \leq 10^{-161}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t\_m}{\mathsf{fma}\left(0.5, \frac{2 \cdot \mathsf{fma}\left(2, {t\_m}^{2}, {l\_m}^{2}\right)}{t\_m \cdot \left(\sqrt{2} \cdot x\right)}, t\_m \cdot \sqrt{2}\right)}\\ \mathbf{elif}\;t\_m \leq 6.3 \cdot 10^{+86}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t\_m}{\sqrt{\left(\frac{t\_3 + t\_3}{{x}^{2}} + \left(2 \cdot \frac{{t\_m}^{2}}{x} + \left(t\_2 + \frac{{l\_m}^{2}}{x}\right)\right)\right) + \frac{t\_3}{x}}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{x + -1}{x + 1}}\\ \end{array} \end{array} \end{array} \]
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 (+ (pow l_m 2.0) t_2)))
   (*
    t_s
    (if (<= t_m 1e-161)
      (*
       (sqrt 2.0)
       (/
        t_m
        (fma
         0.5
         (/
          (* 2.0 (fma 2.0 (pow t_m 2.0) (pow l_m 2.0)))
          (* t_m (* (sqrt 2.0) x)))
         (* t_m (sqrt 2.0)))))
      (if (<= t_m 6.3e+86)
        (*
         (sqrt 2.0)
         (/
          t_m
          (sqrt
           (+
            (+
             (/ (+ t_3 t_3) (pow x 2.0))
             (+ (* 2.0 (/ (pow t_m 2.0) x)) (+ t_2 (/ (pow l_m 2.0) x))))
            (/ t_3 x)))))
        (sqrt (/ (+ x -1.0) (+ x 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 t_2 = 2.0 * pow(t_m, 2.0);
	double t_3 = pow(l_m, 2.0) + t_2;
	double tmp;
	if (t_m <= 1e-161) {
		tmp = sqrt(2.0) * (t_m / fma(0.5, ((2.0 * fma(2.0, pow(t_m, 2.0), pow(l_m, 2.0))) / (t_m * (sqrt(2.0) * x))), (t_m * sqrt(2.0))));
	} else if (t_m <= 6.3e+86) {
		tmp = sqrt(2.0) * (t_m / sqrt(((((t_3 + t_3) / 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(((x + -1.0) / (x + 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)
	t_2 = Float64(2.0 * (t_m ^ 2.0))
	t_3 = Float64((l_m ^ 2.0) + t_2)
	tmp = 0.0
	if (t_m <= 1e-161)
		tmp = Float64(sqrt(2.0) * Float64(t_m / fma(0.5, Float64(Float64(2.0 * fma(2.0, (t_m ^ 2.0), (l_m ^ 2.0))) / Float64(t_m * Float64(sqrt(2.0) * x))), Float64(t_m * sqrt(2.0)))));
	elseif (t_m <= 6.3e+86)
		tmp = Float64(sqrt(2.0) * Float64(t_m / sqrt(Float64(Float64(Float64(Float64(t_3 + t_3) / (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(x + -1.0) / Float64(x + 1.0)));
	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_] := Block[{t$95$2 = N[(2.0 * N[Power[t$95$m, 2.0], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(N[Power[l$95$m, 2.0], $MachinePrecision] + t$95$2), $MachinePrecision]}, N[(t$95$s * If[LessEqual[t$95$m, 1e-161], N[(N[Sqrt[2.0], $MachinePrecision] * N[(t$95$m / N[(0.5 * N[(N[(2.0 * N[(2.0 * N[Power[t$95$m, 2.0], $MachinePrecision] + N[Power[l$95$m, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(t$95$m * N[(N[Sqrt[2.0], $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$m * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$m, 6.3e+86], N[(N[Sqrt[2.0], $MachinePrecision] * N[(t$95$m / N[Sqrt[N[(N[(N[(N[(t$95$3 + t$95$3), $MachinePrecision] / 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[(x + -1.0), $MachinePrecision] / N[(x + 1.0), $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 := {l\_m}^{2} + t\_2\\
t\_s \cdot \begin{array}{l}
\mathbf{if}\;t\_m \leq 10^{-161}:\\
\;\;\;\;\sqrt{2} \cdot \frac{t\_m}{\mathsf{fma}\left(0.5, \frac{2 \cdot \mathsf{fma}\left(2, {t\_m}^{2}, {l\_m}^{2}\right)}{t\_m \cdot \left(\sqrt{2} \cdot x\right)}, t\_m \cdot \sqrt{2}\right)}\\

\mathbf{elif}\;t\_m \leq 6.3 \cdot 10^{+86}:\\
\;\;\;\;\sqrt{2} \cdot \frac{t\_m}{\sqrt{\left(\frac{t\_3 + t\_3}{{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{x + -1}{x + 1}}\\


\end{array}
\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if t < 1.00000000000000003e-161

    1. Initial program 26.8%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified23.4%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Taylor expanded in x around inf 13.6%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{0.5 \cdot \frac{\left(2 \cdot {t}^{2} + {\ell}^{2}\right) - -1 \cdot \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)} + t \cdot \sqrt{2}}} \]
    5. Step-by-step derivation
      1. fma-define13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{\mathsf{fma}\left(0.5, \frac{\left(2 \cdot {t}^{2} + {\ell}^{2}\right) - -1 \cdot \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)}} \]
      2. fma-define13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\color{blue}{\mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)} - -1 \cdot \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
      3. fma-define13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right) - -1 \cdot \color{blue}{\mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
      4. cancel-sign-sub-inv13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\color{blue}{\mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right) + \left(--1\right) \cdot \mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
      5. metadata-eval13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right) + \color{blue}{1} \cdot \mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
      6. distribute-rgt1-in13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\color{blue}{\left(1 + 1\right) \cdot \mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
      7. metadata-eval13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\color{blue}{2} \cdot \mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
    6. Simplified13.6%

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

    if 1.00000000000000003e-161 < t < 6.30000000000000023e86

    1. Initial program 62.7%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified49.8%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Taylor expanded in x around -inf 88.2%

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

    if 6.30000000000000023e86 < t

    1. Initial program 32.4%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified32.2%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Applied egg-rr82.3%

      \[\leadsto \color{blue}{\frac{1}{\frac{\mathsf{hypot}\left(\mathsf{hypot}\left(\ell, t \cdot \sqrt{2}\right) \cdot \sqrt{\frac{x + 1}{x + -1}}, \ell\right)}{t \cdot \sqrt{2}}}} \]
    5. Taylor expanded in l around 0 95.2%

      \[\leadsto \color{blue}{\sqrt{\frac{x - 1}{1 + x}}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification46.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 10^{-161}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{2 \cdot \mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}{t \cdot \left(\sqrt{2} \cdot x\right)}, t \cdot \sqrt{2}\right)}\\ \mathbf{elif}\;t \leq 6.3 \cdot 10^{+86}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t}{\sqrt{\left(\frac{\left({\ell}^{2} + 2 \cdot {t}^{2}\right) + \left({\ell}^{2} + 2 \cdot {t}^{2}\right)}{{x}^{2}} + \left(2 \cdot \frac{{t}^{2}}{x} + \left(2 \cdot {t}^{2} + \frac{{\ell}^{2}}{x}\right)\right)\right) + \frac{{\ell}^{2} + 2 \cdot {t}^{2}}{x}}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{x + -1}{x + 1}}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 84.8% accurate, 0.3× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ t\_s \cdot \begin{array}{l} \mathbf{if}\;t\_m \leq 6.4 \cdot 10^{-162}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t\_m}{\mathsf{fma}\left(0.5, \frac{2 \cdot \mathsf{fma}\left(2, {t\_m}^{2}, {l\_m}^{2}\right)}{t\_m \cdot \left(\sqrt{2} \cdot x\right)}, t\_m \cdot \sqrt{2}\right)}\\ \mathbf{elif}\;t\_m \leq 5.2 \cdot 10^{+86}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t\_m}{\sqrt{\mathsf{fma}\left(2, {t\_m}^{2} \cdot \frac{x + 1}{x + -1}, 2 \cdot \frac{{l\_m}^{2}}{x}\right)}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{x + -1}{x + 1}}\\ \end{array} \end{array} \]
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 (<= t_m 6.4e-162)
    (*
     (sqrt 2.0)
     (/
      t_m
      (fma
       0.5
       (/
        (* 2.0 (fma 2.0 (pow t_m 2.0) (pow l_m 2.0)))
        (* t_m (* (sqrt 2.0) x)))
       (* t_m (sqrt 2.0)))))
    (if (<= t_m 5.2e+86)
      (*
       (sqrt 2.0)
       (/
        t_m
        (sqrt
         (fma
          2.0
          (* (pow t_m 2.0) (/ (+ x 1.0) (+ x -1.0)))
          (* 2.0 (/ (pow l_m 2.0) x))))))
      (sqrt (/ (+ x -1.0) (+ x 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 (t_m <= 6.4e-162) {
		tmp = sqrt(2.0) * (t_m / fma(0.5, ((2.0 * fma(2.0, pow(t_m, 2.0), pow(l_m, 2.0))) / (t_m * (sqrt(2.0) * x))), (t_m * sqrt(2.0))));
	} else if (t_m <= 5.2e+86) {
		tmp = sqrt(2.0) * (t_m / sqrt(fma(2.0, (pow(t_m, 2.0) * ((x + 1.0) / (x + -1.0))), (2.0 * (pow(l_m, 2.0) / x)))));
	} else {
		tmp = sqrt(((x + -1.0) / (x + 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 (t_m <= 6.4e-162)
		tmp = Float64(sqrt(2.0) * Float64(t_m / fma(0.5, Float64(Float64(2.0 * fma(2.0, (t_m ^ 2.0), (l_m ^ 2.0))) / Float64(t_m * Float64(sqrt(2.0) * x))), Float64(t_m * sqrt(2.0)))));
	elseif (t_m <= 5.2e+86)
		tmp = Float64(sqrt(2.0) * Float64(t_m / sqrt(fma(2.0, Float64((t_m ^ 2.0) * Float64(Float64(x + 1.0) / Float64(x + -1.0))), Float64(2.0 * Float64((l_m ^ 2.0) / x))))));
	else
		tmp = sqrt(Float64(Float64(x + -1.0) / Float64(x + 1.0)));
	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[t$95$m, 6.4e-162], N[(N[Sqrt[2.0], $MachinePrecision] * N[(t$95$m / N[(0.5 * N[(N[(2.0 * N[(2.0 * N[Power[t$95$m, 2.0], $MachinePrecision] + N[Power[l$95$m, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(t$95$m * N[(N[Sqrt[2.0], $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(t$95$m * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$m, 5.2e+86], N[(N[Sqrt[2.0], $MachinePrecision] * N[(t$95$m / N[Sqrt[N[(2.0 * N[(N[Power[t$95$m, 2.0], $MachinePrecision] * N[(N[(x + 1.0), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(2.0 * N[(N[Power[l$95$m, 2.0], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[(x + -1.0), $MachinePrecision] / N[(x + 1.0), $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}\;t\_m \leq 6.4 \cdot 10^{-162}:\\
\;\;\;\;\sqrt{2} \cdot \frac{t\_m}{\mathsf{fma}\left(0.5, \frac{2 \cdot \mathsf{fma}\left(2, {t\_m}^{2}, {l\_m}^{2}\right)}{t\_m \cdot \left(\sqrt{2} \cdot x\right)}, t\_m \cdot \sqrt{2}\right)}\\

\mathbf{elif}\;t\_m \leq 5.2 \cdot 10^{+86}:\\
\;\;\;\;\sqrt{2} \cdot \frac{t\_m}{\sqrt{\mathsf{fma}\left(2, {t\_m}^{2} \cdot \frac{x + 1}{x + -1}, 2 \cdot \frac{{l\_m}^{2}}{x}\right)}}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if t < 6.39999999999999951e-162

    1. Initial program 26.8%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified23.4%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Taylor expanded in x around inf 13.6%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{0.5 \cdot \frac{\left(2 \cdot {t}^{2} + {\ell}^{2}\right) - -1 \cdot \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)} + t \cdot \sqrt{2}}} \]
    5. Step-by-step derivation
      1. fma-define13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\color{blue}{\mathsf{fma}\left(0.5, \frac{\left(2 \cdot {t}^{2} + {\ell}^{2}\right) - -1 \cdot \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)}} \]
      2. fma-define13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\color{blue}{\mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)} - -1 \cdot \left(2 \cdot {t}^{2} + {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
      3. fma-define13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right) - -1 \cdot \color{blue}{\mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
      4. cancel-sign-sub-inv13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\color{blue}{\mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right) + \left(--1\right) \cdot \mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
      5. metadata-eval13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right) + \color{blue}{1} \cdot \mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
      6. distribute-rgt1-in13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\color{blue}{\left(1 + 1\right) \cdot \mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
      7. metadata-eval13.6%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{\color{blue}{2} \cdot \mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}{t \cdot \left(x \cdot \sqrt{2}\right)}, t \cdot \sqrt{2}\right)} \]
    6. Simplified13.6%

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

    if 6.39999999999999951e-162 < t < 5.1999999999999995e86

    1. Initial program 62.7%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified49.8%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Taylor expanded in l around 0 63.1%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{2 \cdot \frac{{t}^{2} \cdot \left(1 + x\right)}{x - 1} + {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)}}} \]
    5. Step-by-step derivation
      1. fma-define63.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{\mathsf{fma}\left(2, \frac{{t}^{2} \cdot \left(1 + x\right)}{x - 1}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}}} \]
      2. +-commutative63.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, \frac{{t}^{2} \cdot \color{blue}{\left(x + 1\right)}}{x - 1}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}} \]
      3. associate-*r/81.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, \color{blue}{{t}^{2} \cdot \frac{x + 1}{x - 1}}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}} \]
      4. sub-neg81.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{\color{blue}{x + \left(-1\right)}}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}} \]
      5. metadata-eval81.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{x + \color{blue}{-1}}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}} \]
      6. +-commutative81.1%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{\color{blue}{-1 + x}}, {\ell}^{2} \cdot \left(\left(\frac{1}{x - 1} + \frac{x}{x - 1}\right) - 1\right)\right)}} \]
      7. associate--l+82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \color{blue}{\left(\frac{1}{x - 1} + \left(\frac{x}{x - 1} - 1\right)\right)}\right)}} \]
      8. sub-neg82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{\color{blue}{x + \left(-1\right)}} + \left(\frac{x}{x - 1} - 1\right)\right)\right)}} \]
      9. metadata-eval82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{x + \color{blue}{-1}} + \left(\frac{x}{x - 1} - 1\right)\right)\right)}} \]
      10. +-commutative82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{\color{blue}{-1 + x}} + \left(\frac{x}{x - 1} - 1\right)\right)\right)}} \]
      11. sub-neg82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{x + \left(-1\right)}} - 1\right)\right)\right)}} \]
      12. metadata-eval82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{-1 + x} + \left(\frac{x}{x + \color{blue}{-1}} - 1\right)\right)\right)}} \]
      13. +-commutative82.5%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{-1 + x} + \left(\frac{x}{\color{blue}{-1 + x}} - 1\right)\right)\right)}} \]
    6. Simplified82.5%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{-1 + x}, {\ell}^{2} \cdot \left(\frac{1}{-1 + x} + \left(\frac{x}{-1 + x} - 1\right)\right)\right)}}} \]
    7. Taylor expanded in x around inf 87.8%

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

    if 5.1999999999999995e86 < t

    1. Initial program 32.4%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified32.2%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Applied egg-rr82.3%

      \[\leadsto \color{blue}{\frac{1}{\frac{\mathsf{hypot}\left(\mathsf{hypot}\left(\ell, t \cdot \sqrt{2}\right) \cdot \sqrt{\frac{x + 1}{x + -1}}, \ell\right)}{t \cdot \sqrt{2}}}} \]
    5. Taylor expanded in l around 0 95.2%

      \[\leadsto \color{blue}{\sqrt{\frac{x - 1}{1 + x}}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification46.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 6.4 \cdot 10^{-162}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t}{\mathsf{fma}\left(0.5, \frac{2 \cdot \mathsf{fma}\left(2, {t}^{2}, {\ell}^{2}\right)}{t \cdot \left(\sqrt{2} \cdot x\right)}, t \cdot \sqrt{2}\right)}\\ \mathbf{elif}\;t \leq 5.2 \cdot 10^{+86}:\\ \;\;\;\;\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(2, {t}^{2} \cdot \frac{x + 1}{x + -1}, 2 \cdot \frac{{\ell}^{2}}{x}\right)}}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{x + -1}{x + 1}}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 79.5% accurate, 1.8× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ \begin{array}{l} t_2 := t\_m \cdot \frac{\sqrt{x}}{l\_m}\\ t\_s \cdot \begin{array}{l} \mathbf{if}\;t\_m \leq 4.5 \cdot 10^{-211}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;t\_m \leq 3.6 \cdot 10^{-125}:\\ \;\;\;\;1 + \frac{-1}{x}\\ \mathbf{elif}\;t\_m \leq 1.75 \cdot 10^{-112}:\\ \;\;\;\;t\_2\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{x + -1}{x + 1}}\\ \end{array} \end{array} \end{array} \]
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 (* t_m (/ (sqrt x) l_m))))
   (*
    t_s
    (if (<= t_m 4.5e-211)
      t_2
      (if (<= t_m 3.6e-125)
        (+ 1.0 (/ -1.0 x))
        (if (<= t_m 1.75e-112) t_2 (sqrt (/ (+ x -1.0) (+ x 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 t_2 = t_m * (sqrt(x) / l_m);
	double tmp;
	if (t_m <= 4.5e-211) {
		tmp = t_2;
	} else if (t_m <= 3.6e-125) {
		tmp = 1.0 + (-1.0 / x);
	} else if (t_m <= 1.75e-112) {
		tmp = t_2;
	} else {
		tmp = sqrt(((x + -1.0) / (x + 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) :: t_2
    real(8) :: tmp
    t_2 = t_m * (sqrt(x) / l_m)
    if (t_m <= 4.5d-211) then
        tmp = t_2
    else if (t_m <= 3.6d-125) then
        tmp = 1.0d0 + ((-1.0d0) / x)
    else if (t_m <= 1.75d-112) then
        tmp = t_2
    else
        tmp = sqrt(((x + (-1.0d0)) / (x + 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 t_2 = t_m * (Math.sqrt(x) / l_m);
	double tmp;
	if (t_m <= 4.5e-211) {
		tmp = t_2;
	} else if (t_m <= 3.6e-125) {
		tmp = 1.0 + (-1.0 / x);
	} else if (t_m <= 1.75e-112) {
		tmp = t_2;
	} else {
		tmp = Math.sqrt(((x + -1.0) / (x + 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):
	t_2 = t_m * (math.sqrt(x) / l_m)
	tmp = 0
	if t_m <= 4.5e-211:
		tmp = t_2
	elif t_m <= 3.6e-125:
		tmp = 1.0 + (-1.0 / x)
	elif t_m <= 1.75e-112:
		tmp = t_2
	else:
		tmp = math.sqrt(((x + -1.0) / (x + 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)
	t_2 = Float64(t_m * Float64(sqrt(x) / l_m))
	tmp = 0.0
	if (t_m <= 4.5e-211)
		tmp = t_2;
	elseif (t_m <= 3.6e-125)
		tmp = Float64(1.0 + Float64(-1.0 / x));
	elseif (t_m <= 1.75e-112)
		tmp = t_2;
	else
		tmp = sqrt(Float64(Float64(x + -1.0) / Float64(x + 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)
	t_2 = t_m * (sqrt(x) / l_m);
	tmp = 0.0;
	if (t_m <= 4.5e-211)
		tmp = t_2;
	elseif (t_m <= 3.6e-125)
		tmp = 1.0 + (-1.0 / x);
	elseif (t_m <= 1.75e-112)
		tmp = t_2;
	else
		tmp = sqrt(((x + -1.0) / (x + 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_] := Block[{t$95$2 = N[(t$95$m * N[(N[Sqrt[x], $MachinePrecision] / l$95$m), $MachinePrecision]), $MachinePrecision]}, N[(t$95$s * If[LessEqual[t$95$m, 4.5e-211], t$95$2, If[LessEqual[t$95$m, 3.6e-125], N[(1.0 + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$m, 1.75e-112], t$95$2, N[Sqrt[N[(N[(x + -1.0), $MachinePrecision] / N[(x + 1.0), $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 := t\_m \cdot \frac{\sqrt{x}}{l\_m}\\
t\_s \cdot \begin{array}{l}
\mathbf{if}\;t\_m \leq 4.5 \cdot 10^{-211}:\\
\;\;\;\;t\_2\\

\mathbf{elif}\;t\_m \leq 3.6 \cdot 10^{-125}:\\
\;\;\;\;1 + \frac{-1}{x}\\

\mathbf{elif}\;t\_m \leq 1.75 \cdot 10^{-112}:\\
\;\;\;\;t\_2\\

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


\end{array}
\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if t < 4.4999999999999999e-211 or 3.6000000000000002e-125 < t < 1.74999999999999997e-112

    1. Initial program 27.9%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified24.6%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Taylor expanded in t around 0 2.1%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \color{blue}{\frac{{\ell}^{2}}{x - 1}}, -\ell \cdot \ell\right)}} \]
    5. Taylor expanded in x around inf 20.0%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{\frac{{\ell}^{2} - -1 \cdot {\ell}^{2}}{x}}}} \]
    6. Step-by-step derivation
      1. unpow220.0%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\color{blue}{\ell \cdot \ell} - -1 \cdot {\ell}^{2}}{x}}} \]
      2. fma-neg20.0%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\color{blue}{\mathsf{fma}\left(\ell, \ell, --1 \cdot {\ell}^{2}\right)}}{x}}} \]
      3. neg-mul-120.0%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\mathsf{fma}\left(\ell, \ell, -\color{blue}{\left(-{\ell}^{2}\right)}\right)}{x}}} \]
      4. remove-double-neg20.0%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\mathsf{fma}\left(\ell, \ell, \color{blue}{{\ell}^{2}}\right)}{x}}} \]
    7. Simplified20.0%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{\frac{\mathsf{fma}\left(\ell, \ell, {\ell}^{2}\right)}{x}}}} \]
    8. Taylor expanded in t around 0 18.2%

      \[\leadsto \color{blue}{\frac{t}{\ell} \cdot \sqrt{x}} \]
    9. Step-by-step derivation
      1. associate-*l/18.1%

        \[\leadsto \color{blue}{\frac{t \cdot \sqrt{x}}{\ell}} \]
      2. associate-/l*18.2%

        \[\leadsto \color{blue}{t \cdot \frac{\sqrt{x}}{\ell}} \]
    10. Simplified18.2%

      \[\leadsto \color{blue}{t \cdot \frac{\sqrt{x}}{\ell}} \]

    if 4.4999999999999999e-211 < t < 3.6000000000000002e-125

    1. Initial program 32.4%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified8.3%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Applied egg-rr54.8%

      \[\leadsto \color{blue}{\frac{1}{\frac{\mathsf{hypot}\left(\mathsf{hypot}\left(\ell, t \cdot \sqrt{2}\right) \cdot \sqrt{\frac{x + 1}{x + -1}}, \ell\right)}{t \cdot \sqrt{2}}}} \]
    5. Taylor expanded in l around 0 84.0%

      \[\leadsto \color{blue}{\sqrt{\frac{x - 1}{1 + x}}} \]
    6. Taylor expanded in x around inf 84.0%

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

    if 1.74999999999999997e-112 < t

    1. Initial program 45.3%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified41.6%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Applied egg-rr75.1%

      \[\leadsto \color{blue}{\frac{1}{\frac{\mathsf{hypot}\left(\mathsf{hypot}\left(\ell, t \cdot \sqrt{2}\right) \cdot \sqrt{\frac{x + 1}{x + -1}}, \ell\right)}{t \cdot \sqrt{2}}}} \]
    5. Taylor expanded in l around 0 90.4%

      \[\leadsto \color{blue}{\sqrt{\frac{x - 1}{1 + x}}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification48.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 4.5 \cdot 10^{-211}:\\ \;\;\;\;t \cdot \frac{\sqrt{x}}{\ell}\\ \mathbf{elif}\;t \leq 3.6 \cdot 10^{-125}:\\ \;\;\;\;1 + \frac{-1}{x}\\ \mathbf{elif}\;t \leq 1.75 \cdot 10^{-112}:\\ \;\;\;\;t \cdot \frac{\sqrt{x}}{\ell}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{x + -1}{x + 1}}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 78.9% accurate, 1.9× speedup?

\[\begin{array}{l} l_m = \left|\ell\right| \\ t_m = \left|t\right| \\ t_s = \mathsf{copysign}\left(1, t\right) \\ t\_s \cdot \begin{array}{l} \mathbf{if}\;t\_m \leq 4.2 \cdot 10^{-212} \lor \neg \left(t\_m \leq 3.6 \cdot 10^{-125}\right) \land t\_m \leq 1.8 \cdot 10^{-112}:\\ \;\;\;\;t\_m \cdot \frac{\sqrt{x}}{l\_m}\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1}{x}\\ \end{array} \end{array} \]
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 (or (<= t_m 4.2e-212) (and (not (<= t_m 3.6e-125)) (<= t_m 1.8e-112)))
    (* t_m (/ (sqrt x) l_m))
    (+ 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) {
	double tmp;
	if ((t_m <= 4.2e-212) || (!(t_m <= 3.6e-125) && (t_m <= 1.8e-112))) {
		tmp = t_m * (sqrt(x) / l_m);
	} else {
		tmp = 1.0 + (-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 <= 4.2d-212) .or. (.not. (t_m <= 3.6d-125)) .and. (t_m <= 1.8d-112)) then
        tmp = t_m * (sqrt(x) / l_m)
    else
        tmp = 1.0d0 + ((-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 <= 4.2e-212) || (!(t_m <= 3.6e-125) && (t_m <= 1.8e-112))) {
		tmp = t_m * (Math.sqrt(x) / l_m);
	} else {
		tmp = 1.0 + (-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 <= 4.2e-212) or (not (t_m <= 3.6e-125) and (t_m <= 1.8e-112)):
		tmp = t_m * (math.sqrt(x) / l_m)
	else:
		tmp = 1.0 + (-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 ((t_m <= 4.2e-212) || (!(t_m <= 3.6e-125) && (t_m <= 1.8e-112)))
		tmp = Float64(t_m * Float64(sqrt(x) / l_m));
	else
		tmp = Float64(1.0 + 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 <= 4.2e-212) || (~((t_m <= 3.6e-125)) && (t_m <= 1.8e-112)))
		tmp = t_m * (sqrt(x) / l_m);
	else
		tmp = 1.0 + (-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[Or[LessEqual[t$95$m, 4.2e-212], And[N[Not[LessEqual[t$95$m, 3.6e-125]], $MachinePrecision], LessEqual[t$95$m, 1.8e-112]]], N[(t$95$m * N[(N[Sqrt[x], $MachinePrecision] / l$95$m), $MachinePrecision]), $MachinePrecision], 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 \begin{array}{l}
\mathbf{if}\;t\_m \leq 4.2 \cdot 10^{-212} \lor \neg \left(t\_m \leq 3.6 \cdot 10^{-125}\right) \land t\_m \leq 1.8 \cdot 10^{-112}:\\
\;\;\;\;t\_m \cdot \frac{\sqrt{x}}{l\_m}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 4.1999999999999999e-212 or 3.6000000000000002e-125 < t < 1.8e-112

    1. Initial program 27.9%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified24.6%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Taylor expanded in t around 0 2.1%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \color{blue}{\frac{{\ell}^{2}}{x - 1}}, -\ell \cdot \ell\right)}} \]
    5. Taylor expanded in x around inf 20.0%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{\frac{{\ell}^{2} - -1 \cdot {\ell}^{2}}{x}}}} \]
    6. Step-by-step derivation
      1. unpow220.0%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\color{blue}{\ell \cdot \ell} - -1 \cdot {\ell}^{2}}{x}}} \]
      2. fma-neg20.0%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\color{blue}{\mathsf{fma}\left(\ell, \ell, --1 \cdot {\ell}^{2}\right)}}{x}}} \]
      3. neg-mul-120.0%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\mathsf{fma}\left(\ell, \ell, -\color{blue}{\left(-{\ell}^{2}\right)}\right)}{x}}} \]
      4. remove-double-neg20.0%

        \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\frac{\mathsf{fma}\left(\ell, \ell, \color{blue}{{\ell}^{2}}\right)}{x}}} \]
    7. Simplified20.0%

      \[\leadsto \sqrt{2} \cdot \frac{t}{\sqrt{\color{blue}{\frac{\mathsf{fma}\left(\ell, \ell, {\ell}^{2}\right)}{x}}}} \]
    8. Taylor expanded in t around 0 18.2%

      \[\leadsto \color{blue}{\frac{t}{\ell} \cdot \sqrt{x}} \]
    9. Step-by-step derivation
      1. associate-*l/18.1%

        \[\leadsto \color{blue}{\frac{t \cdot \sqrt{x}}{\ell}} \]
      2. associate-/l*18.2%

        \[\leadsto \color{blue}{t \cdot \frac{\sqrt{x}}{\ell}} \]
    10. Simplified18.2%

      \[\leadsto \color{blue}{t \cdot \frac{\sqrt{x}}{\ell}} \]

    if 4.1999999999999999e-212 < t < 3.6000000000000002e-125 or 1.8e-112 < t

    1. Initial program 43.9%

      \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
    2. Simplified38.0%

      \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
    3. Add Preprocessing
    4. Applied egg-rr72.9%

      \[\leadsto \color{blue}{\frac{1}{\frac{\mathsf{hypot}\left(\mathsf{hypot}\left(\ell, t \cdot \sqrt{2}\right) \cdot \sqrt{\frac{x + 1}{x + -1}}, \ell\right)}{t \cdot \sqrt{2}}}} \]
    5. Taylor expanded in l around 0 89.7%

      \[\leadsto \color{blue}{\sqrt{\frac{x - 1}{1 + x}}} \]
    6. Taylor expanded in x around inf 88.8%

      \[\leadsto \color{blue}{1 - \frac{1}{x}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification48.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 4.2 \cdot 10^{-212} \lor \neg \left(t \leq 3.6 \cdot 10^{-125}\right) \land t \leq 1.8 \cdot 10^{-112}:\\ \;\;\;\;t \cdot \frac{\sqrt{x}}{\ell}\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{-1}{x}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 75.8% 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 34.8%

    \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
  2. Simplified30.3%

    \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
  3. Add Preprocessing
  4. Applied egg-rr68.5%

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

    \[\leadsto \color{blue}{\sqrt{\frac{x - 1}{1 + x}}} \]
  6. Taylor expanded in x around inf 41.2%

    \[\leadsto \color{blue}{1 - \frac{1}{x}} \]
  7. Final simplification41.2%

    \[\leadsto 1 + \frac{-1}{x} \]
  8. Add Preprocessing

Alternative 7: 75.1% 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 34.8%

    \[\frac{\sqrt{2} \cdot t}{\sqrt{\frac{x + 1}{x - 1} \cdot \left(\ell \cdot \ell + 2 \cdot \left(t \cdot t\right)\right) - \ell \cdot \ell}} \]
  2. Simplified30.3%

    \[\leadsto \color{blue}{\sqrt{2} \cdot \frac{t}{\sqrt{\mathsf{fma}\left(x + 1, \frac{\mathsf{fma}\left(2, t \cdot t, \ell \cdot \ell\right)}{x + -1}, -\ell \cdot \ell\right)}}} \]
  3. Add Preprocessing
  4. Applied egg-rr68.5%

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

    \[\leadsto \color{blue}{\sqrt{\frac{x - 1}{1 + x}}} \]
  6. Taylor expanded in x around inf 40.7%

    \[\leadsto \color{blue}{1} \]
  7. Final simplification40.7%

    \[\leadsto 1 \]
  8. Add Preprocessing

Reproduce

?
herbie shell --seed 2024039 
(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)))))