NMSE Section 6.1 mentioned, A

Percentage Accurate: 73.6% → 99.8%
Time: 15.0s
Alternatives: 12
Speedup: 9.7×

Specification

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

\\
\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2}
\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 12 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: 73.6% accurate, 1.0× speedup?

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

\\
\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2}
\end{array}

Alternative 1: 99.8% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := e^{-x}\\ \mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 0:\\ \;\;\;\;0.5 \cdot \mathsf{fma}\left(x + 2, t\_0, x \cdot t\_0\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (exp (- x))))
   (if (<=
        (+
         (* (+ 1.0 (/ 1.0 eps)) (exp (* x (+ eps -1.0))))
         (* (exp (* x (- -1.0 eps))) (+ 1.0 (/ -1.0 eps))))
        0.0)
     (* 0.5 (fma (+ x 2.0) t_0 (* x t_0)))
     (* 0.5 (* 2.0 (cosh (* x eps)))))))
double code(double x, double eps) {
	double t_0 = exp(-x);
	double tmp;
	if ((((1.0 + (1.0 / eps)) * exp((x * (eps + -1.0)))) + (exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 0.0) {
		tmp = 0.5 * fma((x + 2.0), t_0, (x * t_0));
	} else {
		tmp = 0.5 * (2.0 * cosh((x * eps)));
	}
	return tmp;
}
function code(x, eps)
	t_0 = exp(Float64(-x))
	tmp = 0.0
	if (Float64(Float64(Float64(1.0 + Float64(1.0 / eps)) * exp(Float64(x * Float64(eps + -1.0)))) + Float64(exp(Float64(x * Float64(-1.0 - eps))) * Float64(1.0 + Float64(-1.0 / eps)))) <= 0.0)
		tmp = Float64(0.5 * fma(Float64(x + 2.0), t_0, Float64(x * t_0)));
	else
		tmp = Float64(0.5 * Float64(2.0 * cosh(Float64(x * eps))));
	end
	return tmp
end
code[x_, eps_] := Block[{t$95$0 = N[Exp[(-x)], $MachinePrecision]}, If[LessEqual[N[(N[(N[(1.0 + N[(1.0 / eps), $MachinePrecision]), $MachinePrecision] * N[Exp[N[(x * N[(eps + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[(N[Exp[N[(x * N[(-1.0 - eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(1.0 + N[(-1.0 / eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.0], N[(0.5 * N[(N[(x + 2.0), $MachinePrecision] * t$95$0 + N[(x * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.5 * N[(2.0 * N[Cosh[N[(x * eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := e^{-x}\\
\mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 0:\\
\;\;\;\;0.5 \cdot \mathsf{fma}\left(x + 2, t\_0, x \cdot t\_0\right)\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot \left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x))))) < 0.0

    1. Initial program 31.5%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \left(-1 \cdot e^{\mathsf{neg}\left(x\right)} + -1 \cdot \left(x \cdot e^{\mathsf{neg}\left(x\right)}\right)\right)\right)} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \left(-1 \cdot e^{\mathsf{neg}\left(x\right)} + -1 \cdot \left(x \cdot e^{\mathsf{neg}\left(x\right)}\right)\right)\right)} \]
      2. mul-1-negN/A

        \[\leadsto \frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \left(-1 \cdot e^{\mathsf{neg}\left(x\right)} + \color{blue}{\left(\mathsf{neg}\left(x \cdot e^{\mathsf{neg}\left(x\right)}\right)\right)}\right)\right) \]
      3. unsub-negN/A

        \[\leadsto \frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \color{blue}{\left(-1 \cdot e^{\mathsf{neg}\left(x\right)} - x \cdot e^{\mathsf{neg}\left(x\right)}\right)}\right) \]
      4. associate-+l-N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - -1 \cdot e^{\mathsf{neg}\left(x\right)}\right) + x \cdot e^{\mathsf{neg}\left(x\right)}\right)} \]
      5. distribute-rgt1-inN/A

        \[\leadsto \frac{1}{2} \cdot \left(\left(\color{blue}{\left(x + 1\right) \cdot e^{\mathsf{neg}\left(x\right)}} - -1 \cdot e^{\mathsf{neg}\left(x\right)}\right) + x \cdot e^{\mathsf{neg}\left(x\right)}\right) \]
      6. distribute-rgt-out--N/A

        \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(x + 1\right) - -1\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) \]
      7. *-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(x + 1\right) - -1\right) + \color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot x}\right) \]
      8. distribute-lft-outN/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right)} \]
      9. *-lowering-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right)} \]
      10. exp-lowering-exp.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{e^{\mathsf{neg}\left(x\right)}} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right) \]
      11. neg-lowering-neg.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\color{blue}{\mathsf{neg}\left(x\right)}} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right) \]
      12. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x\right)} \cdot \color{blue}{\left(\left(\left(x + 1\right) - -1\right) + x\right)}\right) \]
    5. Simplified99.9%

      \[\leadsto \color{blue}{0.5 \cdot \left(e^{-x} \cdot \left(\left(x + 2\right) + x\right)\right)} \]
    6. Step-by-step derivation
      1. distribute-rgt-inN/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left(x + 2\right) \cdot e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right)} \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\mathsf{fma}\left(x + 2, e^{\mathsf{neg}\left(x\right)}, x \cdot e^{\mathsf{neg}\left(x\right)}\right)} \]
      3. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(\color{blue}{x + 2}, e^{\mathsf{neg}\left(x\right)}, x \cdot e^{\mathsf{neg}\left(x\right)}\right) \]
      4. exp-lowering-exp.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x + 2, \color{blue}{e^{\mathsf{neg}\left(x\right)}}, x \cdot e^{\mathsf{neg}\left(x\right)}\right) \]
      5. neg-lowering-neg.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x + 2, e^{\color{blue}{\mathsf{neg}\left(x\right)}}, x \cdot e^{\mathsf{neg}\left(x\right)}\right) \]
      6. *-lowering-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x + 2, e^{\mathsf{neg}\left(x\right)}, \color{blue}{x \cdot e^{\mathsf{neg}\left(x\right)}}\right) \]
      7. exp-lowering-exp.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x + 2, e^{\mathsf{neg}\left(x\right)}, x \cdot \color{blue}{e^{\mathsf{neg}\left(x\right)}}\right) \]
      8. neg-lowering-neg.f64100.0

        \[\leadsto 0.5 \cdot \mathsf{fma}\left(x + 2, e^{-x}, x \cdot e^{\color{blue}{-x}}\right) \]
    7. Applied egg-rr100.0%

      \[\leadsto 0.5 \cdot \color{blue}{\mathsf{fma}\left(x + 2, e^{-x}, x \cdot e^{-x}\right)} \]

    if 0.0 < (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x)))))

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around inf

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      2. cancel-sign-sub-invN/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \left(\mathsf{neg}\left(-1\right)\right) \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      3. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{1} \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right) \]
      4. *-lft-identityN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}}\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    5. Simplified100.0%

      \[\leadsto \color{blue}{0.5 \cdot \left(e^{x \cdot \varepsilon - x} + e^{x \cdot \left(-1 - \varepsilon\right)}\right)} \]
    6. Taylor expanded in eps around inf

      \[\leadsto \frac{1}{2} \cdot \left(e^{\color{blue}{\varepsilon \cdot x}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
    7. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\color{blue}{x \cdot \varepsilon}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
      2. *-lowering-*.f64100.0

        \[\leadsto 0.5 \cdot \left(e^{\color{blue}{x \cdot \varepsilon}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
    8. Simplified100.0%

      \[\leadsto 0.5 \cdot \left(e^{\color{blue}{x \cdot \varepsilon}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
    9. Taylor expanded in eps around inf

      \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}}\right) \]
    10. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}}\right) \]
      2. *-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{x \cdot \left(-1 \cdot \varepsilon\right)}}\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{x \cdot \left(-1 \cdot \varepsilon\right)}}\right) \]
      4. mul-1-negN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{x \cdot \color{blue}{\left(\mathsf{neg}\left(\varepsilon\right)\right)}}\right) \]
      5. neg-lowering-neg.f64100.0

        \[\leadsto 0.5 \cdot \left(e^{x \cdot \varepsilon} + e^{x \cdot \color{blue}{\left(-\varepsilon\right)}}\right) \]
    11. Simplified100.0%

      \[\leadsto 0.5 \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{x \cdot \left(-\varepsilon\right)}}\right) \]
    12. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \color{blue}{\left(e^{x \cdot \varepsilon} + e^{x \cdot \left(\mathsf{neg}\left(\varepsilon\right)\right)}\right) \cdot \frac{1}{2}} \]
      2. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(e^{x \cdot \varepsilon} + e^{x \cdot \left(\mathsf{neg}\left(\varepsilon\right)\right)}\right) \cdot \frac{1}{2}} \]
      3. distribute-rgt-neg-outN/A

        \[\leadsto \left(e^{x \cdot \varepsilon} + e^{\color{blue}{\mathsf{neg}\left(x \cdot \varepsilon\right)}}\right) \cdot \frac{1}{2} \]
      4. cosh-undefN/A

        \[\leadsto \color{blue}{\left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)} \cdot \frac{1}{2} \]
      5. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)} \cdot \frac{1}{2} \]
      6. cosh-lowering-cosh.f64N/A

        \[\leadsto \left(2 \cdot \color{blue}{\cosh \left(x \cdot \varepsilon\right)}\right) \cdot \frac{1}{2} \]
      7. *-lowering-*.f64100.0

        \[\leadsto \left(2 \cdot \cosh \color{blue}{\left(x \cdot \varepsilon\right)}\right) \cdot 0.5 \]
    13. Applied egg-rr100.0%

      \[\leadsto \color{blue}{\left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right) \cdot 0.5} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification100.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 0:\\ \;\;\;\;0.5 \cdot \mathsf{fma}\left(x + 2, e^{-x}, x \cdot e^{-x}\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 99.8% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 0:\\ \;\;\;\;0.5 \cdot \left(e^{-x} \cdot \left(x + \left(x + 2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (if (<=
      (+
       (* (+ 1.0 (/ 1.0 eps)) (exp (* x (+ eps -1.0))))
       (* (exp (* x (- -1.0 eps))) (+ 1.0 (/ -1.0 eps))))
      0.0)
   (* 0.5 (* (exp (- x)) (+ x (+ x 2.0))))
   (* 0.5 (* 2.0 (cosh (* x eps))))))
double code(double x, double eps) {
	double tmp;
	if ((((1.0 + (1.0 / eps)) * exp((x * (eps + -1.0)))) + (exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 0.0) {
		tmp = 0.5 * (exp(-x) * (x + (x + 2.0)));
	} else {
		tmp = 0.5 * (2.0 * cosh((x * eps)));
	}
	return tmp;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: tmp
    if ((((1.0d0 + (1.0d0 / eps)) * exp((x * (eps + (-1.0d0))))) + (exp((x * ((-1.0d0) - eps))) * (1.0d0 + ((-1.0d0) / eps)))) <= 0.0d0) then
        tmp = 0.5d0 * (exp(-x) * (x + (x + 2.0d0)))
    else
        tmp = 0.5d0 * (2.0d0 * cosh((x * eps)))
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double tmp;
	if ((((1.0 + (1.0 / eps)) * Math.exp((x * (eps + -1.0)))) + (Math.exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 0.0) {
		tmp = 0.5 * (Math.exp(-x) * (x + (x + 2.0)));
	} else {
		tmp = 0.5 * (2.0 * Math.cosh((x * eps)));
	}
	return tmp;
}
def code(x, eps):
	tmp = 0
	if (((1.0 + (1.0 / eps)) * math.exp((x * (eps + -1.0)))) + (math.exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 0.0:
		tmp = 0.5 * (math.exp(-x) * (x + (x + 2.0)))
	else:
		tmp = 0.5 * (2.0 * math.cosh((x * eps)))
	return tmp
function code(x, eps)
	tmp = 0.0
	if (Float64(Float64(Float64(1.0 + Float64(1.0 / eps)) * exp(Float64(x * Float64(eps + -1.0)))) + Float64(exp(Float64(x * Float64(-1.0 - eps))) * Float64(1.0 + Float64(-1.0 / eps)))) <= 0.0)
		tmp = Float64(0.5 * Float64(exp(Float64(-x)) * Float64(x + Float64(x + 2.0))));
	else
		tmp = Float64(0.5 * Float64(2.0 * cosh(Float64(x * eps))));
	end
	return tmp
end
function tmp_2 = code(x, eps)
	tmp = 0.0;
	if ((((1.0 + (1.0 / eps)) * exp((x * (eps + -1.0)))) + (exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 0.0)
		tmp = 0.5 * (exp(-x) * (x + (x + 2.0)));
	else
		tmp = 0.5 * (2.0 * cosh((x * eps)));
	end
	tmp_2 = tmp;
end
code[x_, eps_] := If[LessEqual[N[(N[(N[(1.0 + N[(1.0 / eps), $MachinePrecision]), $MachinePrecision] * N[Exp[N[(x * N[(eps + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[(N[Exp[N[(x * N[(-1.0 - eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(1.0 + N[(-1.0 / eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.0], N[(0.5 * N[(N[Exp[(-x)], $MachinePrecision] * N[(x + N[(x + 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(0.5 * N[(2.0 * N[Cosh[N[(x * eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 0:\\
\;\;\;\;0.5 \cdot \left(e^{-x} \cdot \left(x + \left(x + 2\right)\right)\right)\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot \left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x))))) < 0.0

    1. Initial program 31.5%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \left(-1 \cdot e^{\mathsf{neg}\left(x\right)} + -1 \cdot \left(x \cdot e^{\mathsf{neg}\left(x\right)}\right)\right)\right)} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \left(-1 \cdot e^{\mathsf{neg}\left(x\right)} + -1 \cdot \left(x \cdot e^{\mathsf{neg}\left(x\right)}\right)\right)\right)} \]
      2. mul-1-negN/A

        \[\leadsto \frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \left(-1 \cdot e^{\mathsf{neg}\left(x\right)} + \color{blue}{\left(\mathsf{neg}\left(x \cdot e^{\mathsf{neg}\left(x\right)}\right)\right)}\right)\right) \]
      3. unsub-negN/A

        \[\leadsto \frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \color{blue}{\left(-1 \cdot e^{\mathsf{neg}\left(x\right)} - x \cdot e^{\mathsf{neg}\left(x\right)}\right)}\right) \]
      4. associate-+l-N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - -1 \cdot e^{\mathsf{neg}\left(x\right)}\right) + x \cdot e^{\mathsf{neg}\left(x\right)}\right)} \]
      5. distribute-rgt1-inN/A

        \[\leadsto \frac{1}{2} \cdot \left(\left(\color{blue}{\left(x + 1\right) \cdot e^{\mathsf{neg}\left(x\right)}} - -1 \cdot e^{\mathsf{neg}\left(x\right)}\right) + x \cdot e^{\mathsf{neg}\left(x\right)}\right) \]
      6. distribute-rgt-out--N/A

        \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(x + 1\right) - -1\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) \]
      7. *-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(x + 1\right) - -1\right) + \color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot x}\right) \]
      8. distribute-lft-outN/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right)} \]
      9. *-lowering-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right)} \]
      10. exp-lowering-exp.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{e^{\mathsf{neg}\left(x\right)}} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right) \]
      11. neg-lowering-neg.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\color{blue}{\mathsf{neg}\left(x\right)}} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right) \]
      12. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x\right)} \cdot \color{blue}{\left(\left(\left(x + 1\right) - -1\right) + x\right)}\right) \]
    5. Simplified99.9%

      \[\leadsto \color{blue}{0.5 \cdot \left(e^{-x} \cdot \left(\left(x + 2\right) + x\right)\right)} \]

    if 0.0 < (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x)))))

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around inf

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      2. cancel-sign-sub-invN/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \left(\mathsf{neg}\left(-1\right)\right) \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      3. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{1} \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right) \]
      4. *-lft-identityN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}}\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    5. Simplified100.0%

      \[\leadsto \color{blue}{0.5 \cdot \left(e^{x \cdot \varepsilon - x} + e^{x \cdot \left(-1 - \varepsilon\right)}\right)} \]
    6. Taylor expanded in eps around inf

      \[\leadsto \frac{1}{2} \cdot \left(e^{\color{blue}{\varepsilon \cdot x}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
    7. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\color{blue}{x \cdot \varepsilon}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
      2. *-lowering-*.f64100.0

        \[\leadsto 0.5 \cdot \left(e^{\color{blue}{x \cdot \varepsilon}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
    8. Simplified100.0%

      \[\leadsto 0.5 \cdot \left(e^{\color{blue}{x \cdot \varepsilon}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
    9. Taylor expanded in eps around inf

      \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}}\right) \]
    10. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}}\right) \]
      2. *-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{x \cdot \left(-1 \cdot \varepsilon\right)}}\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{x \cdot \left(-1 \cdot \varepsilon\right)}}\right) \]
      4. mul-1-negN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{x \cdot \color{blue}{\left(\mathsf{neg}\left(\varepsilon\right)\right)}}\right) \]
      5. neg-lowering-neg.f64100.0

        \[\leadsto 0.5 \cdot \left(e^{x \cdot \varepsilon} + e^{x \cdot \color{blue}{\left(-\varepsilon\right)}}\right) \]
    11. Simplified100.0%

      \[\leadsto 0.5 \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{x \cdot \left(-\varepsilon\right)}}\right) \]
    12. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \color{blue}{\left(e^{x \cdot \varepsilon} + e^{x \cdot \left(\mathsf{neg}\left(\varepsilon\right)\right)}\right) \cdot \frac{1}{2}} \]
      2. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(e^{x \cdot \varepsilon} + e^{x \cdot \left(\mathsf{neg}\left(\varepsilon\right)\right)}\right) \cdot \frac{1}{2}} \]
      3. distribute-rgt-neg-outN/A

        \[\leadsto \left(e^{x \cdot \varepsilon} + e^{\color{blue}{\mathsf{neg}\left(x \cdot \varepsilon\right)}}\right) \cdot \frac{1}{2} \]
      4. cosh-undefN/A

        \[\leadsto \color{blue}{\left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)} \cdot \frac{1}{2} \]
      5. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)} \cdot \frac{1}{2} \]
      6. cosh-lowering-cosh.f64N/A

        \[\leadsto \left(2 \cdot \color{blue}{\cosh \left(x \cdot \varepsilon\right)}\right) \cdot \frac{1}{2} \]
      7. *-lowering-*.f64100.0

        \[\leadsto \left(2 \cdot \cosh \color{blue}{\left(x \cdot \varepsilon\right)}\right) \cdot 0.5 \]
    13. Applied egg-rr100.0%

      \[\leadsto \color{blue}{\left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right) \cdot 0.5} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification100.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 0:\\ \;\;\;\;0.5 \cdot \left(e^{-x} \cdot \left(x + \left(x + 2\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 99.0% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 0:\\ \;\;\;\;e^{-x}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (if (<=
      (+
       (* (+ 1.0 (/ 1.0 eps)) (exp (* x (+ eps -1.0))))
       (* (exp (* x (- -1.0 eps))) (+ 1.0 (/ -1.0 eps))))
      0.0)
   (exp (- x))
   (* 0.5 (* 2.0 (cosh (* x eps))))))
double code(double x, double eps) {
	double tmp;
	if ((((1.0 + (1.0 / eps)) * exp((x * (eps + -1.0)))) + (exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 0.0) {
		tmp = exp(-x);
	} else {
		tmp = 0.5 * (2.0 * cosh((x * eps)));
	}
	return tmp;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: tmp
    if ((((1.0d0 + (1.0d0 / eps)) * exp((x * (eps + (-1.0d0))))) + (exp((x * ((-1.0d0) - eps))) * (1.0d0 + ((-1.0d0) / eps)))) <= 0.0d0) then
        tmp = exp(-x)
    else
        tmp = 0.5d0 * (2.0d0 * cosh((x * eps)))
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double tmp;
	if ((((1.0 + (1.0 / eps)) * Math.exp((x * (eps + -1.0)))) + (Math.exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 0.0) {
		tmp = Math.exp(-x);
	} else {
		tmp = 0.5 * (2.0 * Math.cosh((x * eps)));
	}
	return tmp;
}
def code(x, eps):
	tmp = 0
	if (((1.0 + (1.0 / eps)) * math.exp((x * (eps + -1.0)))) + (math.exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 0.0:
		tmp = math.exp(-x)
	else:
		tmp = 0.5 * (2.0 * math.cosh((x * eps)))
	return tmp
function code(x, eps)
	tmp = 0.0
	if (Float64(Float64(Float64(1.0 + Float64(1.0 / eps)) * exp(Float64(x * Float64(eps + -1.0)))) + Float64(exp(Float64(x * Float64(-1.0 - eps))) * Float64(1.0 + Float64(-1.0 / eps)))) <= 0.0)
		tmp = exp(Float64(-x));
	else
		tmp = Float64(0.5 * Float64(2.0 * cosh(Float64(x * eps))));
	end
	return tmp
end
function tmp_2 = code(x, eps)
	tmp = 0.0;
	if ((((1.0 + (1.0 / eps)) * exp((x * (eps + -1.0)))) + (exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 0.0)
		tmp = exp(-x);
	else
		tmp = 0.5 * (2.0 * cosh((x * eps)));
	end
	tmp_2 = tmp;
end
code[x_, eps_] := If[LessEqual[N[(N[(N[(1.0 + N[(1.0 / eps), $MachinePrecision]), $MachinePrecision] * N[Exp[N[(x * N[(eps + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[(N[Exp[N[(x * N[(-1.0 - eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(1.0 + N[(-1.0 / eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.0], N[Exp[(-x)], $MachinePrecision], N[(0.5 * N[(2.0 * N[Cosh[N[(x * eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 0:\\
\;\;\;\;e^{-x}\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot \left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x))))) < 0.0

    1. Initial program 31.5%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around inf

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      2. cancel-sign-sub-invN/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \left(\mathsf{neg}\left(-1\right)\right) \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      3. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{1} \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right) \]
      4. *-lft-identityN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}}\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    5. Simplified98.2%

      \[\leadsto \color{blue}{0.5 \cdot \left(e^{x \cdot \varepsilon - x} + e^{x \cdot \left(-1 - \varepsilon\right)}\right)} \]
    6. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x\right)} + e^{-1 \cdot x}\right)} \]
    7. Step-by-step derivation
      1. distribute-rgt-inN/A

        \[\leadsto \color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot \frac{1}{2} + e^{-1 \cdot x} \cdot \frac{1}{2}} \]
      2. neg-mul-1N/A

        \[\leadsto e^{\mathsf{neg}\left(x\right)} \cdot \frac{1}{2} + e^{\color{blue}{\mathsf{neg}\left(x\right)}} \cdot \frac{1}{2} \]
      3. distribute-lft-outN/A

        \[\leadsto \color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot \left(\frac{1}{2} + \frac{1}{2}\right)} \]
      4. metadata-evalN/A

        \[\leadsto e^{\mathsf{neg}\left(x\right)} \cdot \color{blue}{1} \]
      5. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot 1} \]
      6. neg-mul-1N/A

        \[\leadsto e^{\color{blue}{-1 \cdot x}} \cdot 1 \]
      7. exp-lowering-exp.f64N/A

        \[\leadsto \color{blue}{e^{-1 \cdot x}} \cdot 1 \]
      8. neg-mul-1N/A

        \[\leadsto e^{\color{blue}{\mathsf{neg}\left(x\right)}} \cdot 1 \]
      9. neg-lowering-neg.f6498.2

        \[\leadsto e^{\color{blue}{-x}} \cdot 1 \]
    8. Simplified98.2%

      \[\leadsto \color{blue}{e^{-x} \cdot 1} \]

    if 0.0 < (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x)))))

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around inf

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      2. cancel-sign-sub-invN/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \left(\mathsf{neg}\left(-1\right)\right) \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      3. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{1} \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right) \]
      4. *-lft-identityN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}}\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    5. Simplified100.0%

      \[\leadsto \color{blue}{0.5 \cdot \left(e^{x \cdot \varepsilon - x} + e^{x \cdot \left(-1 - \varepsilon\right)}\right)} \]
    6. Taylor expanded in eps around inf

      \[\leadsto \frac{1}{2} \cdot \left(e^{\color{blue}{\varepsilon \cdot x}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
    7. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\color{blue}{x \cdot \varepsilon}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
      2. *-lowering-*.f64100.0

        \[\leadsto 0.5 \cdot \left(e^{\color{blue}{x \cdot \varepsilon}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
    8. Simplified100.0%

      \[\leadsto 0.5 \cdot \left(e^{\color{blue}{x \cdot \varepsilon}} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \]
    9. Taylor expanded in eps around inf

      \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}}\right) \]
    10. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}}\right) \]
      2. *-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{x \cdot \left(-1 \cdot \varepsilon\right)}}\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{x \cdot \left(-1 \cdot \varepsilon\right)}}\right) \]
      4. mul-1-negN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{x \cdot \varepsilon} + e^{x \cdot \color{blue}{\left(\mathsf{neg}\left(\varepsilon\right)\right)}}\right) \]
      5. neg-lowering-neg.f64100.0

        \[\leadsto 0.5 \cdot \left(e^{x \cdot \varepsilon} + e^{x \cdot \color{blue}{\left(-\varepsilon\right)}}\right) \]
    11. Simplified100.0%

      \[\leadsto 0.5 \cdot \left(e^{x \cdot \varepsilon} + e^{\color{blue}{x \cdot \left(-\varepsilon\right)}}\right) \]
    12. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \color{blue}{\left(e^{x \cdot \varepsilon} + e^{x \cdot \left(\mathsf{neg}\left(\varepsilon\right)\right)}\right) \cdot \frac{1}{2}} \]
      2. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(e^{x \cdot \varepsilon} + e^{x \cdot \left(\mathsf{neg}\left(\varepsilon\right)\right)}\right) \cdot \frac{1}{2}} \]
      3. distribute-rgt-neg-outN/A

        \[\leadsto \left(e^{x \cdot \varepsilon} + e^{\color{blue}{\mathsf{neg}\left(x \cdot \varepsilon\right)}}\right) \cdot \frac{1}{2} \]
      4. cosh-undefN/A

        \[\leadsto \color{blue}{\left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)} \cdot \frac{1}{2} \]
      5. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)} \cdot \frac{1}{2} \]
      6. cosh-lowering-cosh.f64N/A

        \[\leadsto \left(2 \cdot \color{blue}{\cosh \left(x \cdot \varepsilon\right)}\right) \cdot \frac{1}{2} \]
      7. *-lowering-*.f64100.0

        \[\leadsto \left(2 \cdot \cosh \color{blue}{\left(x \cdot \varepsilon\right)}\right) \cdot 0.5 \]
    13. Applied egg-rr100.0%

      \[\leadsto \color{blue}{\left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right) \cdot 0.5} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 0:\\ \;\;\;\;e^{-x}\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(2 \cdot \cosh \left(x \cdot \varepsilon\right)\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 76.8% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + \frac{1}{\varepsilon}\\ t_1 := -1 + \frac{1}{\varepsilon}\\ \mathbf{if}\;t\_0 \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 4:\\ \;\;\;\;e^{-x}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\left(\frac{1}{\varepsilon} + \left(1 + t\_1\right)\right) \cdot \left(1 + \left(1 + \frac{0}{\varepsilon}\right)\right)}{t\_0 + t\_1}}{2}\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (+ 1.0 (/ 1.0 eps))) (t_1 (+ -1.0 (/ 1.0 eps))))
   (if (<=
        (+
         (* t_0 (exp (* x (+ eps -1.0))))
         (* (exp (* x (- -1.0 eps))) (+ 1.0 (/ -1.0 eps))))
        4.0)
     (exp (- x))
     (/
      (/
       (* (+ (/ 1.0 eps) (+ 1.0 t_1)) (+ 1.0 (+ 1.0 (/ 0.0 eps))))
       (+ t_0 t_1))
      2.0))))
double code(double x, double eps) {
	double t_0 = 1.0 + (1.0 / eps);
	double t_1 = -1.0 + (1.0 / eps);
	double tmp;
	if (((t_0 * exp((x * (eps + -1.0)))) + (exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 4.0) {
		tmp = exp(-x);
	} else {
		tmp = ((((1.0 / eps) + (1.0 + t_1)) * (1.0 + (1.0 + (0.0 / eps)))) / (t_0 + t_1)) / 2.0;
	}
	return tmp;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: tmp
    t_0 = 1.0d0 + (1.0d0 / eps)
    t_1 = (-1.0d0) + (1.0d0 / eps)
    if (((t_0 * exp((x * (eps + (-1.0d0))))) + (exp((x * ((-1.0d0) - eps))) * (1.0d0 + ((-1.0d0) / eps)))) <= 4.0d0) then
        tmp = exp(-x)
    else
        tmp = ((((1.0d0 / eps) + (1.0d0 + t_1)) * (1.0d0 + (1.0d0 + (0.0d0 / eps)))) / (t_0 + t_1)) / 2.0d0
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double t_0 = 1.0 + (1.0 / eps);
	double t_1 = -1.0 + (1.0 / eps);
	double tmp;
	if (((t_0 * Math.exp((x * (eps + -1.0)))) + (Math.exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 4.0) {
		tmp = Math.exp(-x);
	} else {
		tmp = ((((1.0 / eps) + (1.0 + t_1)) * (1.0 + (1.0 + (0.0 / eps)))) / (t_0 + t_1)) / 2.0;
	}
	return tmp;
}
def code(x, eps):
	t_0 = 1.0 + (1.0 / eps)
	t_1 = -1.0 + (1.0 / eps)
	tmp = 0
	if ((t_0 * math.exp((x * (eps + -1.0)))) + (math.exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 4.0:
		tmp = math.exp(-x)
	else:
		tmp = ((((1.0 / eps) + (1.0 + t_1)) * (1.0 + (1.0 + (0.0 / eps)))) / (t_0 + t_1)) / 2.0
	return tmp
function code(x, eps)
	t_0 = Float64(1.0 + Float64(1.0 / eps))
	t_1 = Float64(-1.0 + Float64(1.0 / eps))
	tmp = 0.0
	if (Float64(Float64(t_0 * exp(Float64(x * Float64(eps + -1.0)))) + Float64(exp(Float64(x * Float64(-1.0 - eps))) * Float64(1.0 + Float64(-1.0 / eps)))) <= 4.0)
		tmp = exp(Float64(-x));
	else
		tmp = Float64(Float64(Float64(Float64(Float64(1.0 / eps) + Float64(1.0 + t_1)) * Float64(1.0 + Float64(1.0 + Float64(0.0 / eps)))) / Float64(t_0 + t_1)) / 2.0);
	end
	return tmp
end
function tmp_2 = code(x, eps)
	t_0 = 1.0 + (1.0 / eps);
	t_1 = -1.0 + (1.0 / eps);
	tmp = 0.0;
	if (((t_0 * exp((x * (eps + -1.0)))) + (exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 4.0)
		tmp = exp(-x);
	else
		tmp = ((((1.0 / eps) + (1.0 + t_1)) * (1.0 + (1.0 + (0.0 / eps)))) / (t_0 + t_1)) / 2.0;
	end
	tmp_2 = tmp;
end
code[x_, eps_] := Block[{t$95$0 = N[(1.0 + N[(1.0 / eps), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(-1.0 + N[(1.0 / eps), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(t$95$0 * N[Exp[N[(x * N[(eps + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[(N[Exp[N[(x * N[(-1.0 - eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(1.0 + N[(-1.0 / eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 4.0], N[Exp[(-x)], $MachinePrecision], N[(N[(N[(N[(N[(1.0 / eps), $MachinePrecision] + N[(1.0 + t$95$1), $MachinePrecision]), $MachinePrecision] * N[(1.0 + N[(1.0 + N[(0.0 / eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(t$95$0 + t$95$1), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + \frac{1}{\varepsilon}\\
t_1 := -1 + \frac{1}{\varepsilon}\\
\mathbf{if}\;t\_0 \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 4:\\
\;\;\;\;e^{-x}\\

\mathbf{else}:\\
\;\;\;\;\frac{\frac{\left(\frac{1}{\varepsilon} + \left(1 + t\_1\right)\right) \cdot \left(1 + \left(1 + \frac{0}{\varepsilon}\right)\right)}{t\_0 + t\_1}}{2}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x))))) < 4

    1. Initial program 51.6%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around inf

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      2. cancel-sign-sub-invN/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \left(\mathsf{neg}\left(-1\right)\right) \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      3. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{1} \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right) \]
      4. *-lft-identityN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}}\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    5. Simplified98.7%

      \[\leadsto \color{blue}{0.5 \cdot \left(e^{x \cdot \varepsilon - x} + e^{x \cdot \left(-1 - \varepsilon\right)}\right)} \]
    6. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x\right)} + e^{-1 \cdot x}\right)} \]
    7. Step-by-step derivation
      1. distribute-rgt-inN/A

        \[\leadsto \color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot \frac{1}{2} + e^{-1 \cdot x} \cdot \frac{1}{2}} \]
      2. neg-mul-1N/A

        \[\leadsto e^{\mathsf{neg}\left(x\right)} \cdot \frac{1}{2} + e^{\color{blue}{\mathsf{neg}\left(x\right)}} \cdot \frac{1}{2} \]
      3. distribute-lft-outN/A

        \[\leadsto \color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot \left(\frac{1}{2} + \frac{1}{2}\right)} \]
      4. metadata-evalN/A

        \[\leadsto e^{\mathsf{neg}\left(x\right)} \cdot \color{blue}{1} \]
      5. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot 1} \]
      6. neg-mul-1N/A

        \[\leadsto e^{\color{blue}{-1 \cdot x}} \cdot 1 \]
      7. exp-lowering-exp.f64N/A

        \[\leadsto \color{blue}{e^{-1 \cdot x}} \cdot 1 \]
      8. neg-mul-1N/A

        \[\leadsto e^{\color{blue}{\mathsf{neg}\left(x\right)}} \cdot 1 \]
      9. neg-lowering-neg.f6498.2

        \[\leadsto e^{\color{blue}{-x}} \cdot 1 \]
    8. Simplified98.2%

      \[\leadsto \color{blue}{e^{-x} \cdot 1} \]

    if 4 < (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x)))))

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{\mathsf{neg}\left(\left(1 - \varepsilon\right) \cdot x\right)} - \color{blue}{\left(\frac{1}{\varepsilon} - 1\right)}}{2} \]
    4. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{\mathsf{neg}\left(\left(1 - \varepsilon\right) \cdot x\right)} - \color{blue}{\left(\frac{1}{\varepsilon} + \left(\mathsf{neg}\left(1\right)\right)\right)}}{2} \]
      2. metadata-evalN/A

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{\mathsf{neg}\left(\left(1 - \varepsilon\right) \cdot x\right)} - \left(\frac{1}{\varepsilon} + \color{blue}{-1}\right)}{2} \]
      3. +-commutativeN/A

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{\mathsf{neg}\left(\left(1 - \varepsilon\right) \cdot x\right)} - \color{blue}{\left(-1 + \frac{1}{\varepsilon}\right)}}{2} \]
      4. +-lowering-+.f64N/A

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{\mathsf{neg}\left(\left(1 - \varepsilon\right) \cdot x\right)} - \color{blue}{\left(-1 + \frac{1}{\varepsilon}\right)}}{2} \]
      5. /-lowering-/.f6454.3

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(-1 + \color{blue}{\frac{1}{\varepsilon}}\right)}{2} \]
    5. Simplified54.3%

      \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \color{blue}{\left(-1 + \frac{1}{\varepsilon}\right)}}{2} \]
    6. Taylor expanded in x around 0

      \[\leadsto \frac{\color{blue}{\left(1 + \frac{1}{\varepsilon}\right)} - \left(-1 + \frac{1}{\varepsilon}\right)}{2} \]
    7. Step-by-step derivation
      1. +-lowering-+.f64N/A

        \[\leadsto \frac{\color{blue}{\left(1 + \frac{1}{\varepsilon}\right)} - \left(-1 + \frac{1}{\varepsilon}\right)}{2} \]
      2. /-lowering-/.f643.1

        \[\leadsto \frac{\left(1 + \color{blue}{\frac{1}{\varepsilon}}\right) - \left(-1 + \frac{1}{\varepsilon}\right)}{2} \]
    8. Simplified3.1%

      \[\leadsto \frac{\color{blue}{\left(1 + \frac{1}{\varepsilon}\right)} - \left(-1 + \frac{1}{\varepsilon}\right)}{2} \]
    9. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto \frac{\color{blue}{\left(1 + \frac{1}{\varepsilon}\right) + \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right)}}{2} \]
      2. flip-+N/A

        \[\leadsto \frac{\color{blue}{\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(1 + \frac{1}{\varepsilon}\right) - \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right) \cdot \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right)}{\left(1 + \frac{1}{\varepsilon}\right) - \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right)}}}{2} \]
      3. sqr-negN/A

        \[\leadsto \frac{\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(1 + \frac{1}{\varepsilon}\right) - \color{blue}{\left(-1 + \frac{1}{\varepsilon}\right) \cdot \left(-1 + \frac{1}{\varepsilon}\right)}}{\left(1 + \frac{1}{\varepsilon}\right) - \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right)}}{2} \]
      4. /-lowering-/.f64N/A

        \[\leadsto \frac{\color{blue}{\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(1 + \frac{1}{\varepsilon}\right) - \left(-1 + \frac{1}{\varepsilon}\right) \cdot \left(-1 + \frac{1}{\varepsilon}\right)}{\left(1 + \frac{1}{\varepsilon}\right) - \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right)}}}{2} \]
    10. Applied egg-rr49.1%

      \[\leadsto \frac{\color{blue}{\frac{\left(\frac{1}{\varepsilon} + \left(1 + \left(-1 + \frac{1}{\varepsilon}\right)\right)\right) \cdot \left(1 + \left(\frac{0}{\varepsilon} - -1\right)\right)}{\left(1 + \frac{1}{\varepsilon}\right) - \left(1 - \frac{1}{\varepsilon}\right)}}}{2} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification77.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 4:\\ \;\;\;\;e^{-x}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\left(\frac{1}{\varepsilon} + \left(1 + \left(-1 + \frac{1}{\varepsilon}\right)\right)\right) \cdot \left(1 + \left(1 + \frac{0}{\varepsilon}\right)\right)}{\left(1 + \frac{1}{\varepsilon}\right) + \left(-1 + \frac{1}{\varepsilon}\right)}}{2}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 64.0% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + \frac{1}{\varepsilon}\\ t_1 := -1 + \frac{1}{\varepsilon}\\ \mathbf{if}\;t\_0 \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 4:\\ \;\;\;\;\mathsf{fma}\left(0.5, \left(x \cdot \varepsilon\right) \cdot \left(x \cdot \varepsilon\right), 1\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\left(\frac{1}{\varepsilon} + \left(1 + t\_1\right)\right) \cdot \left(1 + \left(1 + \frac{0}{\varepsilon}\right)\right)}{t\_0 + t\_1}}{2}\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (let* ((t_0 (+ 1.0 (/ 1.0 eps))) (t_1 (+ -1.0 (/ 1.0 eps))))
   (if (<=
        (+
         (* t_0 (exp (* x (+ eps -1.0))))
         (* (exp (* x (- -1.0 eps))) (+ 1.0 (/ -1.0 eps))))
        4.0)
     (fma 0.5 (* (* x eps) (* x eps)) 1.0)
     (/
      (/
       (* (+ (/ 1.0 eps) (+ 1.0 t_1)) (+ 1.0 (+ 1.0 (/ 0.0 eps))))
       (+ t_0 t_1))
      2.0))))
double code(double x, double eps) {
	double t_0 = 1.0 + (1.0 / eps);
	double t_1 = -1.0 + (1.0 / eps);
	double tmp;
	if (((t_0 * exp((x * (eps + -1.0)))) + (exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 4.0) {
		tmp = fma(0.5, ((x * eps) * (x * eps)), 1.0);
	} else {
		tmp = ((((1.0 / eps) + (1.0 + t_1)) * (1.0 + (1.0 + (0.0 / eps)))) / (t_0 + t_1)) / 2.0;
	}
	return tmp;
}
function code(x, eps)
	t_0 = Float64(1.0 + Float64(1.0 / eps))
	t_1 = Float64(-1.0 + Float64(1.0 / eps))
	tmp = 0.0
	if (Float64(Float64(t_0 * exp(Float64(x * Float64(eps + -1.0)))) + Float64(exp(Float64(x * Float64(-1.0 - eps))) * Float64(1.0 + Float64(-1.0 / eps)))) <= 4.0)
		tmp = fma(0.5, Float64(Float64(x * eps) * Float64(x * eps)), 1.0);
	else
		tmp = Float64(Float64(Float64(Float64(Float64(1.0 / eps) + Float64(1.0 + t_1)) * Float64(1.0 + Float64(1.0 + Float64(0.0 / eps)))) / Float64(t_0 + t_1)) / 2.0);
	end
	return tmp
end
code[x_, eps_] := Block[{t$95$0 = N[(1.0 + N[(1.0 / eps), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(-1.0 + N[(1.0 / eps), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(t$95$0 * N[Exp[N[(x * N[(eps + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[(N[Exp[N[(x * N[(-1.0 - eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(1.0 + N[(-1.0 / eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 4.0], N[(0.5 * N[(N[(x * eps), $MachinePrecision] * N[(x * eps), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision], N[(N[(N[(N[(N[(1.0 / eps), $MachinePrecision] + N[(1.0 + t$95$1), $MachinePrecision]), $MachinePrecision] * N[(1.0 + N[(1.0 + N[(0.0 / eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(t$95$0 + t$95$1), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + \frac{1}{\varepsilon}\\
t_1 := -1 + \frac{1}{\varepsilon}\\
\mathbf{if}\;t\_0 \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 4:\\
\;\;\;\;\mathsf{fma}\left(0.5, \left(x \cdot \varepsilon\right) \cdot \left(x \cdot \varepsilon\right), 1\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{\frac{\left(\frac{1}{\varepsilon} + \left(1 + t\_1\right)\right) \cdot \left(1 + \left(1 + \frac{0}{\varepsilon}\right)\right)}{t\_0 + t\_1}}{2}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x))))) < 4

    1. Initial program 51.6%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{1 + x \cdot \left(\frac{1}{2} \cdot \left(x \cdot \left(\frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot {\left(\varepsilon - 1\right)}^{2}\right) - \frac{1}{2} \cdot \left({\left(1 + \varepsilon\right)}^{2} \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right) + \frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(\varepsilon - 1\right) - -1 \cdot \left(\left(1 + \varepsilon\right) \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right)} \]
    4. Simplified75.1%

      \[\leadsto \color{blue}{\mathsf{fma}\left(0.5, x \cdot \mathsf{fma}\left(\varepsilon + 1, -1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(0.5 \cdot x, \left(1 - \varepsilon\right) \cdot \left(1 - \varepsilon\right), -1 + \varepsilon\right), -\left(\mathsf{fma}\left(x, \varepsilon, x\right) \cdot \left(\varepsilon + 1\right)\right) \cdot \left(\left(-1 + \frac{1}{\varepsilon}\right) \cdot 0.5\right)\right)\right), 1\right)} \]
    5. Taylor expanded in eps around inf

      \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left({\varepsilon}^{2} \cdot \left(\frac{1}{2} \cdot x - \frac{-1}{2} \cdot x\right)\right)}, 1\right) \]
    6. Step-by-step derivation
      1. distribute-rgt-out--N/A

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \color{blue}{\left(x \cdot \left(\frac{1}{2} - \frac{-1}{2}\right)\right)}\right), 1\right) \]
      2. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \left(x \cdot \color{blue}{1}\right)\right), 1\right) \]
      3. *-rgt-identityN/A

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \color{blue}{x}\right), 1\right) \]
      4. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}, 1\right) \]
      5. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}, 1\right) \]
      6. unpow2N/A

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right), 1\right) \]
      7. *-lowering-*.f6476.6

        \[\leadsto \mathsf{fma}\left(0.5, x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right), 1\right) \]
    7. Simplified76.6%

      \[\leadsto \mathsf{fma}\left(0.5, x \cdot \color{blue}{\left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)}, 1\right) \]
    8. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, \color{blue}{\left(x \cdot x\right) \cdot \left(\varepsilon \cdot \varepsilon\right)}, 1\right) \]
      2. unswap-sqrN/A

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, \color{blue}{\left(x \cdot \varepsilon\right) \cdot \left(x \cdot \varepsilon\right)}, 1\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, \color{blue}{\left(x \cdot \varepsilon\right) \cdot \left(x \cdot \varepsilon\right)}, 1\right) \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, \color{blue}{\left(x \cdot \varepsilon\right)} \cdot \left(x \cdot \varepsilon\right), 1\right) \]
      5. *-lowering-*.f6479.2

        \[\leadsto \mathsf{fma}\left(0.5, \left(x \cdot \varepsilon\right) \cdot \color{blue}{\left(x \cdot \varepsilon\right)}, 1\right) \]
    9. Applied egg-rr79.2%

      \[\leadsto \mathsf{fma}\left(0.5, \color{blue}{\left(x \cdot \varepsilon\right) \cdot \left(x \cdot \varepsilon\right)}, 1\right) \]

    if 4 < (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x)))))

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{\mathsf{neg}\left(\left(1 - \varepsilon\right) \cdot x\right)} - \color{blue}{\left(\frac{1}{\varepsilon} - 1\right)}}{2} \]
    4. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{\mathsf{neg}\left(\left(1 - \varepsilon\right) \cdot x\right)} - \color{blue}{\left(\frac{1}{\varepsilon} + \left(\mathsf{neg}\left(1\right)\right)\right)}}{2} \]
      2. metadata-evalN/A

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{\mathsf{neg}\left(\left(1 - \varepsilon\right) \cdot x\right)} - \left(\frac{1}{\varepsilon} + \color{blue}{-1}\right)}{2} \]
      3. +-commutativeN/A

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{\mathsf{neg}\left(\left(1 - \varepsilon\right) \cdot x\right)} - \color{blue}{\left(-1 + \frac{1}{\varepsilon}\right)}}{2} \]
      4. +-lowering-+.f64N/A

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{\mathsf{neg}\left(\left(1 - \varepsilon\right) \cdot x\right)} - \color{blue}{\left(-1 + \frac{1}{\varepsilon}\right)}}{2} \]
      5. /-lowering-/.f6454.3

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(-1 + \color{blue}{\frac{1}{\varepsilon}}\right)}{2} \]
    5. Simplified54.3%

      \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \color{blue}{\left(-1 + \frac{1}{\varepsilon}\right)}}{2} \]
    6. Taylor expanded in x around 0

      \[\leadsto \frac{\color{blue}{\left(1 + \frac{1}{\varepsilon}\right)} - \left(-1 + \frac{1}{\varepsilon}\right)}{2} \]
    7. Step-by-step derivation
      1. +-lowering-+.f64N/A

        \[\leadsto \frac{\color{blue}{\left(1 + \frac{1}{\varepsilon}\right)} - \left(-1 + \frac{1}{\varepsilon}\right)}{2} \]
      2. /-lowering-/.f643.1

        \[\leadsto \frac{\left(1 + \color{blue}{\frac{1}{\varepsilon}}\right) - \left(-1 + \frac{1}{\varepsilon}\right)}{2} \]
    8. Simplified3.1%

      \[\leadsto \frac{\color{blue}{\left(1 + \frac{1}{\varepsilon}\right)} - \left(-1 + \frac{1}{\varepsilon}\right)}{2} \]
    9. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto \frac{\color{blue}{\left(1 + \frac{1}{\varepsilon}\right) + \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right)}}{2} \]
      2. flip-+N/A

        \[\leadsto \frac{\color{blue}{\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(1 + \frac{1}{\varepsilon}\right) - \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right) \cdot \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right)}{\left(1 + \frac{1}{\varepsilon}\right) - \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right)}}}{2} \]
      3. sqr-negN/A

        \[\leadsto \frac{\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(1 + \frac{1}{\varepsilon}\right) - \color{blue}{\left(-1 + \frac{1}{\varepsilon}\right) \cdot \left(-1 + \frac{1}{\varepsilon}\right)}}{\left(1 + \frac{1}{\varepsilon}\right) - \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right)}}{2} \]
      4. /-lowering-/.f64N/A

        \[\leadsto \frac{\color{blue}{\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(1 + \frac{1}{\varepsilon}\right) - \left(-1 + \frac{1}{\varepsilon}\right) \cdot \left(-1 + \frac{1}{\varepsilon}\right)}{\left(1 + \frac{1}{\varepsilon}\right) - \left(\mathsf{neg}\left(\left(-1 + \frac{1}{\varepsilon}\right)\right)\right)}}}{2} \]
    10. Applied egg-rr49.1%

      \[\leadsto \frac{\color{blue}{\frac{\left(\frac{1}{\varepsilon} + \left(1 + \left(-1 + \frac{1}{\varepsilon}\right)\right)\right) \cdot \left(1 + \left(\frac{0}{\varepsilon} - -1\right)\right)}{\left(1 + \frac{1}{\varepsilon}\right) - \left(1 - \frac{1}{\varepsilon}\right)}}}{2} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification66.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 4:\\ \;\;\;\;\mathsf{fma}\left(0.5, \left(x \cdot \varepsilon\right) \cdot \left(x \cdot \varepsilon\right), 1\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{\left(\frac{1}{\varepsilon} + \left(1 + \left(-1 + \frac{1}{\varepsilon}\right)\right)\right) \cdot \left(1 + \left(1 + \frac{0}{\varepsilon}\right)\right)}{\left(1 + \frac{1}{\varepsilon}\right) + \left(-1 + \frac{1}{\varepsilon}\right)}}{2}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 78.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 4:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(x \cdot \left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right)\\ \end{array} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (if (<=
      (+
       (* (+ 1.0 (/ 1.0 eps)) (exp (* x (+ eps -1.0))))
       (* (exp (* x (- -1.0 eps))) (+ 1.0 (/ -1.0 eps))))
      4.0)
   1.0
   (* 0.5 (* x (* x (* eps eps))))))
double code(double x, double eps) {
	double tmp;
	if ((((1.0 + (1.0 / eps)) * exp((x * (eps + -1.0)))) + (exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 4.0) {
		tmp = 1.0;
	} else {
		tmp = 0.5 * (x * (x * (eps * eps)));
	}
	return tmp;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    real(8) :: tmp
    if ((((1.0d0 + (1.0d0 / eps)) * exp((x * (eps + (-1.0d0))))) + (exp((x * ((-1.0d0) - eps))) * (1.0d0 + ((-1.0d0) / eps)))) <= 4.0d0) then
        tmp = 1.0d0
    else
        tmp = 0.5d0 * (x * (x * (eps * eps)))
    end if
    code = tmp
end function
public static double code(double x, double eps) {
	double tmp;
	if ((((1.0 + (1.0 / eps)) * Math.exp((x * (eps + -1.0)))) + (Math.exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 4.0) {
		tmp = 1.0;
	} else {
		tmp = 0.5 * (x * (x * (eps * eps)));
	}
	return tmp;
}
def code(x, eps):
	tmp = 0
	if (((1.0 + (1.0 / eps)) * math.exp((x * (eps + -1.0)))) + (math.exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 4.0:
		tmp = 1.0
	else:
		tmp = 0.5 * (x * (x * (eps * eps)))
	return tmp
function code(x, eps)
	tmp = 0.0
	if (Float64(Float64(Float64(1.0 + Float64(1.0 / eps)) * exp(Float64(x * Float64(eps + -1.0)))) + Float64(exp(Float64(x * Float64(-1.0 - eps))) * Float64(1.0 + Float64(-1.0 / eps)))) <= 4.0)
		tmp = 1.0;
	else
		tmp = Float64(0.5 * Float64(x * Float64(x * Float64(eps * eps))));
	end
	return tmp
end
function tmp_2 = code(x, eps)
	tmp = 0.0;
	if ((((1.0 + (1.0 / eps)) * exp((x * (eps + -1.0)))) + (exp((x * (-1.0 - eps))) * (1.0 + (-1.0 / eps)))) <= 4.0)
		tmp = 1.0;
	else
		tmp = 0.5 * (x * (x * (eps * eps)));
	end
	tmp_2 = tmp;
end
code[x_, eps_] := If[LessEqual[N[(N[(N[(1.0 + N[(1.0 / eps), $MachinePrecision]), $MachinePrecision] * N[Exp[N[(x * N[(eps + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[(N[Exp[N[(x * N[(-1.0 - eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(1.0 + N[(-1.0 / eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 4.0], 1.0, N[(0.5 * N[(x * N[(x * N[(eps * eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 4:\\
\;\;\;\;1\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot \left(x \cdot \left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x))))) < 4

    1. Initial program 51.6%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{1} \]
    4. Step-by-step derivation
      1. Simplified79.0%

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

      if 4 < (-.f64 (*.f64 (+.f64 #s(literal 1 binary64) (/.f64 #s(literal 1 binary64) eps)) (exp.f64 (neg.f64 (*.f64 (-.f64 #s(literal 1 binary64) eps) x)))) (*.f64 (-.f64 (/.f64 #s(literal 1 binary64) eps) #s(literal 1 binary64)) (exp.f64 (neg.f64 (*.f64 (+.f64 #s(literal 1 binary64) eps) x)))))

      1. Initial program 100.0%

        \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \color{blue}{1 + x \cdot \left(\frac{1}{2} \cdot \left(x \cdot \left(\frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot {\left(\varepsilon - 1\right)}^{2}\right) - \frac{1}{2} \cdot \left({\left(1 + \varepsilon\right)}^{2} \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right) + \frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(\varepsilon - 1\right) - -1 \cdot \left(\left(1 + \varepsilon\right) \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right)} \]
      4. Simplified86.6%

        \[\leadsto \color{blue}{\mathsf{fma}\left(0.5, x \cdot \mathsf{fma}\left(\varepsilon + 1, -1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(0.5 \cdot x, \left(1 - \varepsilon\right) \cdot \left(1 - \varepsilon\right), -1 + \varepsilon\right), -\left(\mathsf{fma}\left(x, \varepsilon, x\right) \cdot \left(\varepsilon + 1\right)\right) \cdot \left(\left(-1 + \frac{1}{\varepsilon}\right) \cdot 0.5\right)\right)\right), 1\right)} \]
      5. Taylor expanded in eps around inf

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left({\varepsilon}^{2} \cdot \left(\frac{1}{2} \cdot x - \frac{-1}{2} \cdot x\right)\right)}, 1\right) \]
      6. Step-by-step derivation
        1. distribute-rgt-out--N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \color{blue}{\left(x \cdot \left(\frac{1}{2} - \frac{-1}{2}\right)\right)}\right), 1\right) \]
        2. metadata-evalN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \left(x \cdot \color{blue}{1}\right)\right), 1\right) \]
        3. *-rgt-identityN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \color{blue}{x}\right), 1\right) \]
        4. *-commutativeN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}, 1\right) \]
        5. *-lowering-*.f64N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}, 1\right) \]
        6. unpow2N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right), 1\right) \]
        7. *-lowering-*.f6486.6

          \[\leadsto \mathsf{fma}\left(0.5, x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right), 1\right) \]
      7. Simplified86.6%

        \[\leadsto \mathsf{fma}\left(0.5, x \cdot \color{blue}{\left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)}, 1\right) \]
      8. Taylor expanded in x around inf

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({\varepsilon}^{2} \cdot {x}^{2}\right)} \]
      9. Step-by-step derivation
        1. *-lowering-*.f64N/A

          \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({\varepsilon}^{2} \cdot {x}^{2}\right)} \]
        2. *-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left({x}^{2} \cdot {\varepsilon}^{2}\right)} \]
        3. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot {\varepsilon}^{2}\right) \]
        4. associate-*l*N/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(x \cdot \left(x \cdot {\varepsilon}^{2}\right)\right)} \]
        5. *-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \color{blue}{\left({\varepsilon}^{2} \cdot x\right)}\right) \]
        6. *-lowering-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(x \cdot \left({\varepsilon}^{2} \cdot x\right)\right)} \]
        7. *-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}\right) \]
        8. *-lowering-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}\right) \]
        9. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right)\right) \]
        10. *-lowering-*.f6486.6

          \[\leadsto 0.5 \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right)\right) \]
      10. Simplified86.6%

        \[\leadsto \color{blue}{0.5 \cdot \left(x \cdot \left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right)} \]
    5. Recombined 2 regimes into one program.
    6. Final simplification82.1%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{x \cdot \left(\varepsilon + -1\right)} + e^{x \cdot \left(-1 - \varepsilon\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right) \leq 4:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(x \cdot \left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right)\\ \end{array} \]
    7. Add Preprocessing

    Alternative 7: 99.0% accurate, 1.2× speedup?

    \[\begin{array}{l} \\ 0.5 \cdot \left(e^{x \cdot \varepsilon - x} + e^{x \cdot \left(-1 - \varepsilon\right)}\right) \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (* 0.5 (+ (exp (- (* x eps) x)) (exp (* x (- -1.0 eps))))))
    double code(double x, double eps) {
    	return 0.5 * (exp(((x * eps) - x)) + exp((x * (-1.0 - eps))));
    }
    
    real(8) function code(x, eps)
        real(8), intent (in) :: x
        real(8), intent (in) :: eps
        code = 0.5d0 * (exp(((x * eps) - x)) + exp((x * ((-1.0d0) - eps))))
    end function
    
    public static double code(double x, double eps) {
    	return 0.5 * (Math.exp(((x * eps) - x)) + Math.exp((x * (-1.0 - eps))));
    }
    
    def code(x, eps):
    	return 0.5 * (math.exp(((x * eps) - x)) + math.exp((x * (-1.0 - eps))))
    
    function code(x, eps)
    	return Float64(0.5 * Float64(exp(Float64(Float64(x * eps) - x)) + exp(Float64(x * Float64(-1.0 - eps)))))
    end
    
    function tmp = code(x, eps)
    	tmp = 0.5 * (exp(((x * eps) - x)) + exp((x * (-1.0 - eps))));
    end
    
    code[x_, eps_] := N[(0.5 * N[(N[Exp[N[(N[(x * eps), $MachinePrecision] - x), $MachinePrecision]], $MachinePrecision] + N[Exp[N[(x * N[(-1.0 - eps), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    0.5 \cdot \left(e^{x \cdot \varepsilon - x} + e^{x \cdot \left(-1 - \varepsilon\right)}\right)
    \end{array}
    
    Derivation
    1. Initial program 71.6%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around inf

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      2. cancel-sign-sub-invN/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \left(\mathsf{neg}\left(-1\right)\right) \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      3. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{1} \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right) \]
      4. *-lft-identityN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}}\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    5. Simplified99.2%

      \[\leadsto \color{blue}{0.5 \cdot \left(e^{x \cdot \varepsilon - x} + e^{x \cdot \left(-1 - \varepsilon\right)}\right)} \]
    6. Add Preprocessing

    Alternative 8: 83.3% accurate, 3.5× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 0.0078:\\ \;\;\;\;\mathsf{fma}\left(0.5, x \cdot \mathsf{fma}\left(\varepsilon + 1, -1 + \frac{1}{\varepsilon}, \frac{\mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \left(1 - x\right) + \mathsf{fma}\left(x, \varepsilon, x\right), 0\right) - x, -1\right)}{\varepsilon}\right), 1\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(x \cdot \left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right)\\ \end{array} \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (if (<= x 0.0078)
       (fma
        0.5
        (*
         x
         (fma
          (+ eps 1.0)
          (+ -1.0 (/ 1.0 eps))
          (/ (fma eps (- (fma eps (+ (- 1.0 x) (fma x eps x)) 0.0) x) -1.0) eps)))
        1.0)
       (* 0.5 (* x (* x (* eps eps))))))
    double code(double x, double eps) {
    	double tmp;
    	if (x <= 0.0078) {
    		tmp = fma(0.5, (x * fma((eps + 1.0), (-1.0 + (1.0 / eps)), (fma(eps, (fma(eps, ((1.0 - x) + fma(x, eps, x)), 0.0) - x), -1.0) / eps))), 1.0);
    	} else {
    		tmp = 0.5 * (x * (x * (eps * eps)));
    	}
    	return tmp;
    }
    
    function code(x, eps)
    	tmp = 0.0
    	if (x <= 0.0078)
    		tmp = fma(0.5, Float64(x * fma(Float64(eps + 1.0), Float64(-1.0 + Float64(1.0 / eps)), Float64(fma(eps, Float64(fma(eps, Float64(Float64(1.0 - x) + fma(x, eps, x)), 0.0) - x), -1.0) / eps))), 1.0);
    	else
    		tmp = Float64(0.5 * Float64(x * Float64(x * Float64(eps * eps))));
    	end
    	return tmp
    end
    
    code[x_, eps_] := If[LessEqual[x, 0.0078], N[(0.5 * N[(x * N[(N[(eps + 1.0), $MachinePrecision] * N[(-1.0 + N[(1.0 / eps), $MachinePrecision]), $MachinePrecision] + N[(N[(eps * N[(N[(eps * N[(N[(1.0 - x), $MachinePrecision] + N[(x * eps + x), $MachinePrecision]), $MachinePrecision] + 0.0), $MachinePrecision] - x), $MachinePrecision] + -1.0), $MachinePrecision] / eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision], N[(0.5 * N[(x * N[(x * N[(eps * eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;x \leq 0.0078:\\
    \;\;\;\;\mathsf{fma}\left(0.5, x \cdot \mathsf{fma}\left(\varepsilon + 1, -1 + \frac{1}{\varepsilon}, \frac{\mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \left(1 - x\right) + \mathsf{fma}\left(x, \varepsilon, x\right), 0\right) - x, -1\right)}{\varepsilon}\right), 1\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;0.5 \cdot \left(x \cdot \left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if x < 0.0077999999999999996

      1. Initial program 61.4%

        \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \color{blue}{1 + x \cdot \left(\frac{1}{2} \cdot \left(x \cdot \left(\frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot {\left(\varepsilon - 1\right)}^{2}\right) - \frac{1}{2} \cdot \left({\left(1 + \varepsilon\right)}^{2} \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right) + \frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(\varepsilon - 1\right) - -1 \cdot \left(\left(1 + \varepsilon\right) \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right)} \]
      4. Simplified91.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(0.5, x \cdot \mathsf{fma}\left(\varepsilon + 1, -1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(0.5 \cdot x, \left(1 - \varepsilon\right) \cdot \left(1 - \varepsilon\right), -1 + \varepsilon\right), -\left(\mathsf{fma}\left(x, \varepsilon, x\right) \cdot \left(\varepsilon + 1\right)\right) \cdot \left(\left(-1 + \frac{1}{\varepsilon}\right) \cdot 0.5\right)\right)\right), 1\right)} \]
      5. Taylor expanded in eps around 0

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \mathsf{fma}\left(\varepsilon + 1, -1 + \frac{1}{\varepsilon}, \color{blue}{\frac{\varepsilon \cdot \left(\left(-1 \cdot x + \left(\frac{1}{2} \cdot x + \varepsilon \cdot \left(\left(1 + \left(-1 \cdot x + \left(\frac{1}{2} \cdot x + \varepsilon \cdot \left(\frac{1}{2} \cdot x - \frac{-1}{2} \cdot x\right)\right)\right)\right) - \frac{1}{2} \cdot \left(x + -2 \cdot x\right)\right)\right)\right) - \frac{1}{2} \cdot \left(-1 \cdot x + 2 \cdot x\right)\right) - 1}{\varepsilon}}\right), 1\right) \]
      6. Simplified93.9%

        \[\leadsto \mathsf{fma}\left(0.5, x \cdot \mathsf{fma}\left(\varepsilon + 1, -1 + \frac{1}{\varepsilon}, \color{blue}{\frac{\mathsf{fma}\left(\varepsilon, \left(-x\right) + \mathsf{fma}\left(\varepsilon, \left(1 - x\right) + \mathsf{fma}\left(x, \varepsilon, x\right), 0\right), -1\right)}{\varepsilon}}\right), 1\right) \]

      if 0.0077999999999999996 < x

      1. Initial program 100.0%

        \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \color{blue}{1 + x \cdot \left(\frac{1}{2} \cdot \left(x \cdot \left(\frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot {\left(\varepsilon - 1\right)}^{2}\right) - \frac{1}{2} \cdot \left({\left(1 + \varepsilon\right)}^{2} \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right) + \frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(\varepsilon - 1\right) - -1 \cdot \left(\left(1 + \varepsilon\right) \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right)} \]
      4. Simplified46.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(0.5, x \cdot \mathsf{fma}\left(\varepsilon + 1, -1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(0.5 \cdot x, \left(1 - \varepsilon\right) \cdot \left(1 - \varepsilon\right), -1 + \varepsilon\right), -\left(\mathsf{fma}\left(x, \varepsilon, x\right) \cdot \left(\varepsilon + 1\right)\right) \cdot \left(\left(-1 + \frac{1}{\varepsilon}\right) \cdot 0.5\right)\right)\right), 1\right)} \]
      5. Taylor expanded in eps around inf

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left({\varepsilon}^{2} \cdot \left(\frac{1}{2} \cdot x - \frac{-1}{2} \cdot x\right)\right)}, 1\right) \]
      6. Step-by-step derivation
        1. distribute-rgt-out--N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \color{blue}{\left(x \cdot \left(\frac{1}{2} - \frac{-1}{2}\right)\right)}\right), 1\right) \]
        2. metadata-evalN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \left(x \cdot \color{blue}{1}\right)\right), 1\right) \]
        3. *-rgt-identityN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \color{blue}{x}\right), 1\right) \]
        4. *-commutativeN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}, 1\right) \]
        5. *-lowering-*.f64N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}, 1\right) \]
        6. unpow2N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right), 1\right) \]
        7. *-lowering-*.f6447.3

          \[\leadsto \mathsf{fma}\left(0.5, x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right), 1\right) \]
      7. Simplified47.3%

        \[\leadsto \mathsf{fma}\left(0.5, x \cdot \color{blue}{\left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)}, 1\right) \]
      8. Taylor expanded in x around inf

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({\varepsilon}^{2} \cdot {x}^{2}\right)} \]
      9. Step-by-step derivation
        1. *-lowering-*.f64N/A

          \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({\varepsilon}^{2} \cdot {x}^{2}\right)} \]
        2. *-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left({x}^{2} \cdot {\varepsilon}^{2}\right)} \]
        3. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot {\varepsilon}^{2}\right) \]
        4. associate-*l*N/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(x \cdot \left(x \cdot {\varepsilon}^{2}\right)\right)} \]
        5. *-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \color{blue}{\left({\varepsilon}^{2} \cdot x\right)}\right) \]
        6. *-lowering-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(x \cdot \left({\varepsilon}^{2} \cdot x\right)\right)} \]
        7. *-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}\right) \]
        8. *-lowering-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}\right) \]
        9. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right)\right) \]
        10. *-lowering-*.f6464.4

          \[\leadsto 0.5 \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right)\right) \]
      10. Simplified64.4%

        \[\leadsto \color{blue}{0.5 \cdot \left(x \cdot \left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right)} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification86.0%

      \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.0078:\\ \;\;\;\;\mathsf{fma}\left(0.5, x \cdot \mathsf{fma}\left(\varepsilon + 1, -1 + \frac{1}{\varepsilon}, \frac{\mathsf{fma}\left(\varepsilon, \mathsf{fma}\left(\varepsilon, \left(1 - x\right) + \mathsf{fma}\left(x, \varepsilon, x\right), 0\right) - x, -1\right)}{\varepsilon}\right), 1\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(x \cdot \left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right)\\ \end{array} \]
    5. Add Preprocessing

    Alternative 9: 82.0% accurate, 9.7× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := x \cdot \left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\\ \mathbf{if}\;x \leq 0.0078:\\ \;\;\;\;\mathsf{fma}\left(0.5, t\_0, 1\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot t\_0\\ \end{array} \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (let* ((t_0 (* x (* x (* eps eps)))))
       (if (<= x 0.0078) (fma 0.5 t_0 1.0) (* 0.5 t_0))))
    double code(double x, double eps) {
    	double t_0 = x * (x * (eps * eps));
    	double tmp;
    	if (x <= 0.0078) {
    		tmp = fma(0.5, t_0, 1.0);
    	} else {
    		tmp = 0.5 * t_0;
    	}
    	return tmp;
    }
    
    function code(x, eps)
    	t_0 = Float64(x * Float64(x * Float64(eps * eps)))
    	tmp = 0.0
    	if (x <= 0.0078)
    		tmp = fma(0.5, t_0, 1.0);
    	else
    		tmp = Float64(0.5 * t_0);
    	end
    	return tmp
    end
    
    code[x_, eps_] := Block[{t$95$0 = N[(x * N[(x * N[(eps * eps), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 0.0078], N[(0.5 * t$95$0 + 1.0), $MachinePrecision], N[(0.5 * t$95$0), $MachinePrecision]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := x \cdot \left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\\
    \mathbf{if}\;x \leq 0.0078:\\
    \;\;\;\;\mathsf{fma}\left(0.5, t\_0, 1\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;0.5 \cdot t\_0\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if x < 0.0077999999999999996

      1. Initial program 61.4%

        \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \color{blue}{1 + x \cdot \left(\frac{1}{2} \cdot \left(x \cdot \left(\frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot {\left(\varepsilon - 1\right)}^{2}\right) - \frac{1}{2} \cdot \left({\left(1 + \varepsilon\right)}^{2} \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right) + \frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(\varepsilon - 1\right) - -1 \cdot \left(\left(1 + \varepsilon\right) \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right)} \]
      4. Simplified91.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(0.5, x \cdot \mathsf{fma}\left(\varepsilon + 1, -1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(0.5 \cdot x, \left(1 - \varepsilon\right) \cdot \left(1 - \varepsilon\right), -1 + \varepsilon\right), -\left(\mathsf{fma}\left(x, \varepsilon, x\right) \cdot \left(\varepsilon + 1\right)\right) \cdot \left(\left(-1 + \frac{1}{\varepsilon}\right) \cdot 0.5\right)\right)\right), 1\right)} \]
      5. Taylor expanded in eps around inf

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left({\varepsilon}^{2} \cdot \left(\frac{1}{2} \cdot x - \frac{-1}{2} \cdot x\right)\right)}, 1\right) \]
      6. Step-by-step derivation
        1. distribute-rgt-out--N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \color{blue}{\left(x \cdot \left(\frac{1}{2} - \frac{-1}{2}\right)\right)}\right), 1\right) \]
        2. metadata-evalN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \left(x \cdot \color{blue}{1}\right)\right), 1\right) \]
        3. *-rgt-identityN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \color{blue}{x}\right), 1\right) \]
        4. *-commutativeN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}, 1\right) \]
        5. *-lowering-*.f64N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}, 1\right) \]
        6. unpow2N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right), 1\right) \]
        7. *-lowering-*.f6492.9

          \[\leadsto \mathsf{fma}\left(0.5, x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right), 1\right) \]
      7. Simplified92.9%

        \[\leadsto \mathsf{fma}\left(0.5, x \cdot \color{blue}{\left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)}, 1\right) \]

      if 0.0077999999999999996 < x

      1. Initial program 100.0%

        \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \color{blue}{1 + x \cdot \left(\frac{1}{2} \cdot \left(x \cdot \left(\frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot {\left(\varepsilon - 1\right)}^{2}\right) - \frac{1}{2} \cdot \left({\left(1 + \varepsilon\right)}^{2} \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right) + \frac{1}{2} \cdot \left(\left(1 + \frac{1}{\varepsilon}\right) \cdot \left(\varepsilon - 1\right) - -1 \cdot \left(\left(1 + \varepsilon\right) \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)\right)} \]
      4. Simplified46.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(0.5, x \cdot \mathsf{fma}\left(\varepsilon + 1, -1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(1 + \frac{1}{\varepsilon}, \mathsf{fma}\left(0.5 \cdot x, \left(1 - \varepsilon\right) \cdot \left(1 - \varepsilon\right), -1 + \varepsilon\right), -\left(\mathsf{fma}\left(x, \varepsilon, x\right) \cdot \left(\varepsilon + 1\right)\right) \cdot \left(\left(-1 + \frac{1}{\varepsilon}\right) \cdot 0.5\right)\right)\right), 1\right)} \]
      5. Taylor expanded in eps around inf

        \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left({\varepsilon}^{2} \cdot \left(\frac{1}{2} \cdot x - \frac{-1}{2} \cdot x\right)\right)}, 1\right) \]
      6. Step-by-step derivation
        1. distribute-rgt-out--N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \color{blue}{\left(x \cdot \left(\frac{1}{2} - \frac{-1}{2}\right)\right)}\right), 1\right) \]
        2. metadata-evalN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \left(x \cdot \color{blue}{1}\right)\right), 1\right) \]
        3. *-rgt-identityN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left({\varepsilon}^{2} \cdot \color{blue}{x}\right), 1\right) \]
        4. *-commutativeN/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}, 1\right) \]
        5. *-lowering-*.f64N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}, 1\right) \]
        6. unpow2N/A

          \[\leadsto \mathsf{fma}\left(\frac{1}{2}, x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right), 1\right) \]
        7. *-lowering-*.f6447.3

          \[\leadsto \mathsf{fma}\left(0.5, x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right), 1\right) \]
      7. Simplified47.3%

        \[\leadsto \mathsf{fma}\left(0.5, x \cdot \color{blue}{\left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)}, 1\right) \]
      8. Taylor expanded in x around inf

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({\varepsilon}^{2} \cdot {x}^{2}\right)} \]
      9. Step-by-step derivation
        1. *-lowering-*.f64N/A

          \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({\varepsilon}^{2} \cdot {x}^{2}\right)} \]
        2. *-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left({x}^{2} \cdot {\varepsilon}^{2}\right)} \]
        3. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot {\varepsilon}^{2}\right) \]
        4. associate-*l*N/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(x \cdot \left(x \cdot {\varepsilon}^{2}\right)\right)} \]
        5. *-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \color{blue}{\left({\varepsilon}^{2} \cdot x\right)}\right) \]
        6. *-lowering-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(x \cdot \left({\varepsilon}^{2} \cdot x\right)\right)} \]
        7. *-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}\right) \]
        8. *-lowering-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \color{blue}{\left(x \cdot {\varepsilon}^{2}\right)}\right) \]
        9. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right)\right) \]
        10. *-lowering-*.f6464.4

          \[\leadsto 0.5 \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(\varepsilon \cdot \varepsilon\right)}\right)\right) \]
      10. Simplified64.4%

        \[\leadsto \color{blue}{0.5 \cdot \left(x \cdot \left(x \cdot \left(\varepsilon \cdot \varepsilon\right)\right)\right)} \]
    3. Recombined 2 regimes into one program.
    4. Add Preprocessing

    Alternative 10: 63.0% accurate, 11.4× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -430:\\ \;\;\;\;\mathsf{fma}\left(-0.16666666666666666, x \cdot \left(x \cdot x\right), 1\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, 0.3333333333333333, -0.5\right), 1\right)\\ \end{array} \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (if (<= x -430.0)
       (fma -0.16666666666666666 (* x (* x x)) 1.0)
       (fma (* x x) (fma x 0.3333333333333333 -0.5) 1.0)))
    double code(double x, double eps) {
    	double tmp;
    	if (x <= -430.0) {
    		tmp = fma(-0.16666666666666666, (x * (x * x)), 1.0);
    	} else {
    		tmp = fma((x * x), fma(x, 0.3333333333333333, -0.5), 1.0);
    	}
    	return tmp;
    }
    
    function code(x, eps)
    	tmp = 0.0
    	if (x <= -430.0)
    		tmp = fma(-0.16666666666666666, Float64(x * Float64(x * x)), 1.0);
    	else
    		tmp = fma(Float64(x * x), fma(x, 0.3333333333333333, -0.5), 1.0);
    	end
    	return tmp
    end
    
    code[x_, eps_] := If[LessEqual[x, -430.0], N[(-0.16666666666666666 * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision], N[(N[(x * x), $MachinePrecision] * N[(x * 0.3333333333333333 + -0.5), $MachinePrecision] + 1.0), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;x \leq -430:\\
    \;\;\;\;\mathsf{fma}\left(-0.16666666666666666, x \cdot \left(x \cdot x\right), 1\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, 0.3333333333333333, -0.5\right), 1\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if x < -430

      1. Initial program 100.0%

        \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
      2. Add Preprocessing
      3. Taylor expanded in eps around inf

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      4. Step-by-step derivation
        1. *-lowering-*.f64N/A

          \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
        2. cancel-sign-sub-invN/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \left(\mathsf{neg}\left(-1\right)\right) \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
        3. metadata-evalN/A

          \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{1} \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right) \]
        4. *-lft-identityN/A

          \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}}\right) \]
        5. +-lowering-+.f64N/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      5. Simplified100.0%

        \[\leadsto \color{blue}{0.5 \cdot \left(e^{x \cdot \varepsilon - x} + e^{x \cdot \left(-1 - \varepsilon\right)}\right)} \]
      6. Taylor expanded in x around 0

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(2 + x \cdot \left(\left(\varepsilon + \left(-1 \cdot \left(1 + \varepsilon\right) + x \cdot \left(\frac{1}{2} \cdot {\left(1 + \varepsilon\right)}^{2} + \left(\frac{1}{2} \cdot {\left(\varepsilon - 1\right)}^{2} + x \cdot \left(\frac{-1}{6} \cdot {\left(1 + \varepsilon\right)}^{3} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right)\right)\right)\right)\right) - 1\right)\right)} \]
      7. Simplified16.7%

        \[\leadsto 0.5 \cdot \color{blue}{\mathsf{fma}\left(x, \varepsilon + \mathsf{fma}\left(x, \mathsf{fma}\left(0.5, \mathsf{fma}\left(1 + \varepsilon, 1 + \varepsilon, \left(\varepsilon + -1\right) \cdot \left(\varepsilon + -1\right)\right), x \cdot \mathsf{fma}\left(\left(\varepsilon + -1\right) \cdot \left(\varepsilon + -1\right), \left(\varepsilon + -1\right) \cdot 0.16666666666666666, \left(\left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right)\right) \cdot \left(\left(1 + \varepsilon\right) \cdot -0.16666666666666666\right)\right)\right), -1 + \left(-1 - \varepsilon\right)\right), 2\right)} \]
      8. Taylor expanded in x around inf

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \color{blue}{{x}^{2} \cdot \left(\frac{-1}{6} \cdot {\left(1 + \varepsilon\right)}^{3} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right)}, 2\right) \]
      9. Step-by-step derivation
        1. *-lowering-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \color{blue}{{x}^{2} \cdot \left(\frac{-1}{6} \cdot {\left(1 + \varepsilon\right)}^{3} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right)}, 2\right) \]
        2. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{-1}{6} \cdot {\left(1 + \varepsilon\right)}^{3} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        3. *-lowering-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{-1}{6} \cdot {\left(1 + \varepsilon\right)}^{3} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        4. cube-multN/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(\frac{-1}{6} \cdot \color{blue}{\left(\left(1 + \varepsilon\right) \cdot \left(\left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right)\right)\right)} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        5. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(\frac{-1}{6} \cdot \left(\left(1 + \varepsilon\right) \cdot \color{blue}{{\left(1 + \varepsilon\right)}^{2}}\right) + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        6. associate-*r*N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(\color{blue}{\left(\frac{-1}{6} \cdot \left(1 + \varepsilon\right)\right) \cdot {\left(1 + \varepsilon\right)}^{2}} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        7. accelerator-lowering-fma.f64N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \color{blue}{\mathsf{fma}\left(\frac{-1}{6} \cdot \left(1 + \varepsilon\right), {\left(1 + \varepsilon\right)}^{2}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right)}, 2\right) \]
        8. +-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\frac{-1}{6} \cdot \color{blue}{\left(\varepsilon + 1\right)}, {\left(1 + \varepsilon\right)}^{2}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        9. distribute-rgt-inN/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\color{blue}{\varepsilon \cdot \frac{-1}{6} + 1 \cdot \frac{-1}{6}}, {\left(1 + \varepsilon\right)}^{2}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        10. metadata-evalN/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\varepsilon \cdot \frac{-1}{6} + \color{blue}{\frac{-1}{6}}, {\left(1 + \varepsilon\right)}^{2}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        11. accelerator-lowering-fma.f64N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right)}, {\left(1 + \varepsilon\right)}^{2}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        12. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \color{blue}{\left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right)}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        13. *-lowering-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \color{blue}{\left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right)}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        14. +-lowering-+.f64N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \color{blue}{\left(1 + \varepsilon\right)} \cdot \left(1 + \varepsilon\right), \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        15. +-lowering-+.f64N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \left(1 + \varepsilon\right) \cdot \color{blue}{\left(1 + \varepsilon\right)}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
        16. cube-multN/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right), \frac{1}{6} \cdot \color{blue}{\left(\left(\varepsilon - 1\right) \cdot \left(\left(\varepsilon - 1\right) \cdot \left(\varepsilon - 1\right)\right)\right)}\right), 2\right) \]
        17. unpow2N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right), \frac{1}{6} \cdot \left(\left(\varepsilon - 1\right) \cdot \color{blue}{{\left(\varepsilon - 1\right)}^{2}}\right)\right), 2\right) \]
        18. associate-*r*N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right), \color{blue}{\left(\frac{1}{6} \cdot \left(\varepsilon - 1\right)\right) \cdot {\left(\varepsilon - 1\right)}^{2}}\right), 2\right) \]
        19. *-lowering-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right), \color{blue}{\left(\frac{1}{6} \cdot \left(\varepsilon - 1\right)\right) \cdot {\left(\varepsilon - 1\right)}^{2}}\right), 2\right) \]
      10. Simplified22.4%

        \[\leadsto 0.5 \cdot \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, -0.16666666666666666, -0.16666666666666666\right), \left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right), \mathsf{fma}\left(\varepsilon, 0.16666666666666666, -0.16666666666666666\right) \cdot \left(\left(\varepsilon + -1\right) \cdot \left(\varepsilon + -1\right)\right)\right)}, 2\right) \]
      11. Taylor expanded in eps around 0

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(2 + \frac{-1}{3} \cdot {x}^{3}\right)} \]
      12. Step-by-step derivation
        1. +-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\frac{-1}{3} \cdot {x}^{3} + 2\right)} \]
        2. distribute-lft-inN/A

          \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\frac{-1}{3} \cdot {x}^{3}\right) + \frac{1}{2} \cdot 2} \]
        3. associate-*r*N/A

          \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \frac{-1}{3}\right) \cdot {x}^{3}} + \frac{1}{2} \cdot 2 \]
        4. metadata-evalN/A

          \[\leadsto \color{blue}{\frac{-1}{6}} \cdot {x}^{3} + \frac{1}{2} \cdot 2 \]
        5. metadata-evalN/A

          \[\leadsto \frac{-1}{6} \cdot {x}^{3} + \color{blue}{1} \]
        6. accelerator-lowering-fma.f64N/A

          \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{-1}{6}, {x}^{3}, 1\right)} \]
        7. cube-multN/A

          \[\leadsto \mathsf{fma}\left(\frac{-1}{6}, \color{blue}{x \cdot \left(x \cdot x\right)}, 1\right) \]
        8. unpow2N/A

          \[\leadsto \mathsf{fma}\left(\frac{-1}{6}, x \cdot \color{blue}{{x}^{2}}, 1\right) \]
        9. *-lowering-*.f64N/A

          \[\leadsto \mathsf{fma}\left(\frac{-1}{6}, \color{blue}{x \cdot {x}^{2}}, 1\right) \]
        10. unpow2N/A

          \[\leadsto \mathsf{fma}\left(\frac{-1}{6}, x \cdot \color{blue}{\left(x \cdot x\right)}, 1\right) \]
        11. *-lowering-*.f6471.2

          \[\leadsto \mathsf{fma}\left(-0.16666666666666666, x \cdot \color{blue}{\left(x \cdot x\right)}, 1\right) \]
      13. Simplified71.2%

        \[\leadsto \color{blue}{\mathsf{fma}\left(-0.16666666666666666, x \cdot \left(x \cdot x\right), 1\right)} \]

      if -430 < x

      1. Initial program 67.0%

        \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
      2. Add Preprocessing
      3. Taylor expanded in eps around 0

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \left(-1 \cdot e^{\mathsf{neg}\left(x\right)} + -1 \cdot \left(x \cdot e^{\mathsf{neg}\left(x\right)}\right)\right)\right)} \]
      4. Step-by-step derivation
        1. *-lowering-*.f64N/A

          \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \left(-1 \cdot e^{\mathsf{neg}\left(x\right)} + -1 \cdot \left(x \cdot e^{\mathsf{neg}\left(x\right)}\right)\right)\right)} \]
        2. mul-1-negN/A

          \[\leadsto \frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \left(-1 \cdot e^{\mathsf{neg}\left(x\right)} + \color{blue}{\left(\mathsf{neg}\left(x \cdot e^{\mathsf{neg}\left(x\right)}\right)\right)}\right)\right) \]
        3. unsub-negN/A

          \[\leadsto \frac{1}{2} \cdot \left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - \color{blue}{\left(-1 \cdot e^{\mathsf{neg}\left(x\right)} - x \cdot e^{\mathsf{neg}\left(x\right)}\right)}\right) \]
        4. associate-+l-N/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\left(\left(e^{\mathsf{neg}\left(x\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) - -1 \cdot e^{\mathsf{neg}\left(x\right)}\right) + x \cdot e^{\mathsf{neg}\left(x\right)}\right)} \]
        5. distribute-rgt1-inN/A

          \[\leadsto \frac{1}{2} \cdot \left(\left(\color{blue}{\left(x + 1\right) \cdot e^{\mathsf{neg}\left(x\right)}} - -1 \cdot e^{\mathsf{neg}\left(x\right)}\right) + x \cdot e^{\mathsf{neg}\left(x\right)}\right) \]
        6. distribute-rgt-out--N/A

          \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(x + 1\right) - -1\right)} + x \cdot e^{\mathsf{neg}\left(x\right)}\right) \]
        7. *-commutativeN/A

          \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(x + 1\right) - -1\right) + \color{blue}{e^{\mathsf{neg}\left(x\right)} \cdot x}\right) \]
        8. distribute-lft-outN/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right)} \]
        9. *-lowering-*.f64N/A

          \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x\right)} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right)} \]
        10. exp-lowering-exp.f64N/A

          \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{e^{\mathsf{neg}\left(x\right)}} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right) \]
        11. neg-lowering-neg.f64N/A

          \[\leadsto \frac{1}{2} \cdot \left(e^{\color{blue}{\mathsf{neg}\left(x\right)}} \cdot \left(\left(\left(x + 1\right) - -1\right) + x\right)\right) \]
        12. +-lowering-+.f64N/A

          \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x\right)} \cdot \color{blue}{\left(\left(\left(x + 1\right) - -1\right) + x\right)}\right) \]
      5. Simplified68.6%

        \[\leadsto \color{blue}{0.5 \cdot \left(e^{-x} \cdot \left(\left(x + 2\right) + x\right)\right)} \]
      6. Taylor expanded in x around 0

        \[\leadsto \color{blue}{1 + {x}^{2} \cdot \left(\frac{1}{3} \cdot x - \frac{1}{2}\right)} \]
      7. Step-by-step derivation
        1. +-commutativeN/A

          \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{3} \cdot x - \frac{1}{2}\right) + 1} \]
        2. accelerator-lowering-fma.f64N/A

          \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{3} \cdot x - \frac{1}{2}, 1\right)} \]
        3. unpow2N/A

          \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{3} \cdot x - \frac{1}{2}, 1\right) \]
        4. *-lowering-*.f64N/A

          \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{3} \cdot x - \frac{1}{2}, 1\right) \]
        5. sub-negN/A

          \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{1}{3} \cdot x + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}, 1\right) \]
        6. *-commutativeN/A

          \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \frac{1}{3}} + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right), 1\right) \]
        7. metadata-evalN/A

          \[\leadsto \mathsf{fma}\left(x \cdot x, x \cdot \frac{1}{3} + \color{blue}{\frac{-1}{2}}, 1\right) \]
        8. accelerator-lowering-fma.f6465.4

          \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, 0.3333333333333333, -0.5\right)}, 1\right) \]
      8. Simplified65.4%

        \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, 0.3333333333333333, -0.5\right), 1\right)} \]
    3. Recombined 2 regimes into one program.
    4. Add Preprocessing

    Alternative 11: 52.7% accurate, 16.1× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left(-0.16666666666666666, x \cdot \left(x \cdot x\right), 1\right) \end{array} \]
    (FPCore (x eps)
     :precision binary64
     (fma -0.16666666666666666 (* x (* x x)) 1.0))
    double code(double x, double eps) {
    	return fma(-0.16666666666666666, (x * (x * x)), 1.0);
    }
    
    function code(x, eps)
    	return fma(-0.16666666666666666, Float64(x * Float64(x * x)), 1.0)
    end
    
    code[x_, eps_] := N[(-0.16666666666666666 * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left(-0.16666666666666666, x \cdot \left(x \cdot x\right), 1\right)
    \end{array}
    
    Derivation
    1. Initial program 71.6%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in eps around inf

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} - -1 \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      2. cancel-sign-sub-invN/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \left(\mathsf{neg}\left(-1\right)\right) \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
      3. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{1} \cdot e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right) \]
      4. *-lft-identityN/A

        \[\leadsto \frac{1}{2} \cdot \left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + \color{blue}{e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}}\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(e^{\mathsf{neg}\left(x \cdot \left(1 - \varepsilon\right)\right)} + e^{\mathsf{neg}\left(x \cdot \left(1 + \varepsilon\right)\right)}\right)} \]
    5. Simplified99.2%

      \[\leadsto \color{blue}{0.5 \cdot \left(e^{x \cdot \varepsilon - x} + e^{x \cdot \left(-1 - \varepsilon\right)}\right)} \]
    6. Taylor expanded in x around 0

      \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(2 + x \cdot \left(\left(\varepsilon + \left(-1 \cdot \left(1 + \varepsilon\right) + x \cdot \left(\frac{1}{2} \cdot {\left(1 + \varepsilon\right)}^{2} + \left(\frac{1}{2} \cdot {\left(\varepsilon - 1\right)}^{2} + x \cdot \left(\frac{-1}{6} \cdot {\left(1 + \varepsilon\right)}^{3} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right)\right)\right)\right)\right) - 1\right)\right)} \]
    7. Simplified45.8%

      \[\leadsto 0.5 \cdot \color{blue}{\mathsf{fma}\left(x, \varepsilon + \mathsf{fma}\left(x, \mathsf{fma}\left(0.5, \mathsf{fma}\left(1 + \varepsilon, 1 + \varepsilon, \left(\varepsilon + -1\right) \cdot \left(\varepsilon + -1\right)\right), x \cdot \mathsf{fma}\left(\left(\varepsilon + -1\right) \cdot \left(\varepsilon + -1\right), \left(\varepsilon + -1\right) \cdot 0.16666666666666666, \left(\left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right)\right) \cdot \left(\left(1 + \varepsilon\right) \cdot -0.16666666666666666\right)\right)\right), -1 + \left(-1 - \varepsilon\right)\right), 2\right)} \]
    8. Taylor expanded in x around inf

      \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \color{blue}{{x}^{2} \cdot \left(\frac{-1}{6} \cdot {\left(1 + \varepsilon\right)}^{3} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right)}, 2\right) \]
    9. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \color{blue}{{x}^{2} \cdot \left(\frac{-1}{6} \cdot {\left(1 + \varepsilon\right)}^{3} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right)}, 2\right) \]
      2. unpow2N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{-1}{6} \cdot {\left(1 + \varepsilon\right)}^{3} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{-1}{6} \cdot {\left(1 + \varepsilon\right)}^{3} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      4. cube-multN/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(\frac{-1}{6} \cdot \color{blue}{\left(\left(1 + \varepsilon\right) \cdot \left(\left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right)\right)\right)} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      5. unpow2N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(\frac{-1}{6} \cdot \left(\left(1 + \varepsilon\right) \cdot \color{blue}{{\left(1 + \varepsilon\right)}^{2}}\right) + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      6. associate-*r*N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(\color{blue}{\left(\frac{-1}{6} \cdot \left(1 + \varepsilon\right)\right) \cdot {\left(1 + \varepsilon\right)}^{2}} + \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      7. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \color{blue}{\mathsf{fma}\left(\frac{-1}{6} \cdot \left(1 + \varepsilon\right), {\left(1 + \varepsilon\right)}^{2}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right)}, 2\right) \]
      8. +-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\frac{-1}{6} \cdot \color{blue}{\left(\varepsilon + 1\right)}, {\left(1 + \varepsilon\right)}^{2}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      9. distribute-rgt-inN/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\color{blue}{\varepsilon \cdot \frac{-1}{6} + 1 \cdot \frac{-1}{6}}, {\left(1 + \varepsilon\right)}^{2}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      10. metadata-evalN/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\varepsilon \cdot \frac{-1}{6} + \color{blue}{\frac{-1}{6}}, {\left(1 + \varepsilon\right)}^{2}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      11. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right)}, {\left(1 + \varepsilon\right)}^{2}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      12. unpow2N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \color{blue}{\left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right)}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      13. *-lowering-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \color{blue}{\left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right)}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      14. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \color{blue}{\left(1 + \varepsilon\right)} \cdot \left(1 + \varepsilon\right), \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      15. +-lowering-+.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \left(1 + \varepsilon\right) \cdot \color{blue}{\left(1 + \varepsilon\right)}, \frac{1}{6} \cdot {\left(\varepsilon - 1\right)}^{3}\right), 2\right) \]
      16. cube-multN/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right), \frac{1}{6} \cdot \color{blue}{\left(\left(\varepsilon - 1\right) \cdot \left(\left(\varepsilon - 1\right) \cdot \left(\varepsilon - 1\right)\right)\right)}\right), 2\right) \]
      17. unpow2N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right), \frac{1}{6} \cdot \left(\left(\varepsilon - 1\right) \cdot \color{blue}{{\left(\varepsilon - 1\right)}^{2}}\right)\right), 2\right) \]
      18. associate-*r*N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right), \color{blue}{\left(\frac{1}{6} \cdot \left(\varepsilon - 1\right)\right) \cdot {\left(\varepsilon - 1\right)}^{2}}\right), 2\right) \]
      19. *-lowering-*.f64N/A

        \[\leadsto \frac{1}{2} \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, \frac{-1}{6}, \frac{-1}{6}\right), \left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right), \color{blue}{\left(\frac{1}{6} \cdot \left(\varepsilon - 1\right)\right) \cdot {\left(\varepsilon - 1\right)}^{2}}\right), 2\right) \]
    10. Simplified46.1%

      \[\leadsto 0.5 \cdot \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\varepsilon, -0.16666666666666666, -0.16666666666666666\right), \left(1 + \varepsilon\right) \cdot \left(1 + \varepsilon\right), \mathsf{fma}\left(\varepsilon, 0.16666666666666666, -0.16666666666666666\right) \cdot \left(\left(\varepsilon + -1\right) \cdot \left(\varepsilon + -1\right)\right)\right)}, 2\right) \]
    11. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(2 + \frac{-1}{3} \cdot {x}^{3}\right)} \]
    12. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(\frac{-1}{3} \cdot {x}^{3} + 2\right)} \]
      2. distribute-lft-inN/A

        \[\leadsto \color{blue}{\frac{1}{2} \cdot \left(\frac{-1}{3} \cdot {x}^{3}\right) + \frac{1}{2} \cdot 2} \]
      3. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \frac{-1}{3}\right) \cdot {x}^{3}} + \frac{1}{2} \cdot 2 \]
      4. metadata-evalN/A

        \[\leadsto \color{blue}{\frac{-1}{6}} \cdot {x}^{3} + \frac{1}{2} \cdot 2 \]
      5. metadata-evalN/A

        \[\leadsto \frac{-1}{6} \cdot {x}^{3} + \color{blue}{1} \]
      6. accelerator-lowering-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{-1}{6}, {x}^{3}, 1\right)} \]
      7. cube-multN/A

        \[\leadsto \mathsf{fma}\left(\frac{-1}{6}, \color{blue}{x \cdot \left(x \cdot x\right)}, 1\right) \]
      8. unpow2N/A

        \[\leadsto \mathsf{fma}\left(\frac{-1}{6}, x \cdot \color{blue}{{x}^{2}}, 1\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{-1}{6}, \color{blue}{x \cdot {x}^{2}}, 1\right) \]
      10. unpow2N/A

        \[\leadsto \mathsf{fma}\left(\frac{-1}{6}, x \cdot \color{blue}{\left(x \cdot x\right)}, 1\right) \]
      11. *-lowering-*.f6456.6

        \[\leadsto \mathsf{fma}\left(-0.16666666666666666, x \cdot \color{blue}{\left(x \cdot x\right)}, 1\right) \]
    13. Simplified56.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.16666666666666666, x \cdot \left(x \cdot x\right), 1\right)} \]
    14. Add Preprocessing

    Alternative 12: 44.1% accurate, 273.0× speedup?

    \[\begin{array}{l} \\ 1 \end{array} \]
    (FPCore (x eps) :precision binary64 1.0)
    double code(double x, double eps) {
    	return 1.0;
    }
    
    real(8) function code(x, eps)
        real(8), intent (in) :: x
        real(8), intent (in) :: eps
        code = 1.0d0
    end function
    
    public static double code(double x, double eps) {
    	return 1.0;
    }
    
    def code(x, eps):
    	return 1.0
    
    function code(x, eps)
    	return 1.0
    end
    
    function tmp = code(x, eps)
    	tmp = 1.0;
    end
    
    code[x_, eps_] := 1.0
    
    \begin{array}{l}
    
    \\
    1
    \end{array}
    
    Derivation
    1. Initial program 71.6%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{1} \]
    4. Step-by-step derivation
      1. Simplified47.6%

        \[\leadsto \color{blue}{1} \]
      2. Add Preprocessing

      Reproduce

      ?
      herbie shell --seed 2024198 
      (FPCore (x eps)
        :name "NMSE Section 6.1 mentioned, A"
        :precision binary64
        (/ (- (* (+ 1.0 (/ 1.0 eps)) (exp (- (* (- 1.0 eps) x)))) (* (- (/ 1.0 eps) 1.0) (exp (- (* (+ 1.0 eps) x))))) 2.0))