Hyperbolic secant

Percentage Accurate: 100.0% → 100.0%
Time: 8.9s
Alternatives: 13
Speedup: 1.9×

Specification

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

\\
\frac{2}{e^{x} + e^{-x}}
\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 13 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: 100.0% accurate, 1.0× speedup?

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

\\
\frac{2}{e^{x} + e^{-x}}
\end{array}

Alternative 1: 100.0% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \frac{1}{\cosh x} \end{array} \]
(FPCore (x) :precision binary64 (/ 1.0 (cosh x)))
double code(double x) {
	return 1.0 / cosh(x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.0d0 / cosh(x)
end function
public static double code(double x) {
	return 1.0 / Math.cosh(x);
}
def code(x):
	return 1.0 / math.cosh(x)
function code(x)
	return Float64(1.0 / cosh(x))
end
function tmp = code(x)
	tmp = 1.0 / cosh(x);
end
code[x_] := N[(1.0 / N[Cosh[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\cosh x}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{2}{e^{x} + e^{-x}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. clear-numN/A

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

      \[\leadsto \frac{1}{\color{blue}{\cosh x}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
    4. cosh-lowering-cosh.f64100.0

      \[\leadsto \frac{1}{\color{blue}{\cosh x}} \]
  4. Applied egg-rr100.0%

    \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
  5. Add Preprocessing

Alternative 2: 91.7% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{2}{e^{x} + e^{-x}} \leq 0:\\ \;\;\;\;\frac{2}{x \cdot \left(x \cdot \left(x \cdot \left(x \cdot \mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\right)\right)\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.08472222222222223, 0.20833333333333334\right), -0.5\right), 1\right)\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= (/ 2.0 (+ (exp x) (exp (- x)))) 0.0)
   (/
    2.0
    (*
     x
     (* x (* x (* x (fma x (* x 0.002777777777777778) 0.08333333333333333))))))
   (fma
    (* x x)
    (fma (* x x) (fma x (* x -0.08472222222222223) 0.20833333333333334) -0.5)
    1.0)))
double code(double x) {
	double tmp;
	if ((2.0 / (exp(x) + exp(-x))) <= 0.0) {
		tmp = 2.0 / (x * (x * (x * (x * fma(x, (x * 0.002777777777777778), 0.08333333333333333)))));
	} else {
		tmp = fma((x * x), fma((x * x), fma(x, (x * -0.08472222222222223), 0.20833333333333334), -0.5), 1.0);
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (Float64(2.0 / Float64(exp(x) + exp(Float64(-x)))) <= 0.0)
		tmp = Float64(2.0 / Float64(x * Float64(x * Float64(x * Float64(x * fma(x, Float64(x * 0.002777777777777778), 0.08333333333333333))))));
	else
		tmp = fma(Float64(x * x), fma(Float64(x * x), fma(x, Float64(x * -0.08472222222222223), 0.20833333333333334), -0.5), 1.0);
	end
	return tmp
end
code[x_] := If[LessEqual[N[(2.0 / N[(N[Exp[x], $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.0], N[(2.0 / N[(x * N[(x * N[(x * N[(x * N[(x * N[(x * 0.002777777777777778), $MachinePrecision] + 0.08333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * -0.08472222222222223), $MachinePrecision] + 0.20833333333333334), $MachinePrecision] + -0.5), $MachinePrecision] + 1.0), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{2}{e^{x} + e^{-x}} \leq 0:\\
\;\;\;\;\frac{2}{x \cdot \left(x \cdot \left(x \cdot \left(x \cdot \mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\right)\right)\right)\right)}\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.08472222222222223, 0.20833333333333334\right), -0.5\right), 1\right)\\


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

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \frac{2}{\color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 2}} \]
      2. unpow2N/A

        \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right)} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 2} \]
      3. associate-*l*N/A

        \[\leadsto \frac{2}{\color{blue}{x \cdot \left(x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)} + 2} \]
      4. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right), 2\right)}} \]
    5. Simplified87.1%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot \mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\right), x\right), 2\right)}} \]
    6. Step-by-step derivation
      1. distribute-rgt-inN/A

        \[\leadsto \frac{2}{\color{blue}{\left(\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)\right) \cdot x + x \cdot x\right)} + 2} \]
      2. associate-+l+N/A

        \[\leadsto \frac{2}{\color{blue}{\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)\right) \cdot x + \left(x \cdot x + 2\right)}} \]
      3. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right), x, x \cdot x + 2\right)}} \]
      4. *-lowering-*.f64N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\color{blue}{\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)}, x, x \cdot x + 2\right)} \]
      5. *-lowering-*.f64N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\color{blue}{\left(x \cdot x\right)} \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right), x, x \cdot x + 2\right)} \]
      6. *-lowering-*.f64N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \color{blue}{\left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)}, x, x \cdot x + 2\right)} \]
      7. associate-*r*N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(\color{blue}{\left(x \cdot x\right) \cdot \frac{1}{360}} + \frac{1}{12}\right)\right), x, x \cdot x + 2\right)} \]
      8. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \frac{1}{360}, \frac{1}{12}\right)}\right), x, x \cdot x + 2\right)} \]
      9. *-lowering-*.f64N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{360}, \frac{1}{12}\right)\right), x, x \cdot x + 2\right)} \]
      10. accelerator-lowering-fma.f6487.1

        \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), x, \color{blue}{\mathsf{fma}\left(x, x, 2\right)}\right)} \]
    7. Applied egg-rr87.1%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), x, \mathsf{fma}\left(x, x, 2\right)\right)}} \]
    8. Taylor expanded in x around inf

      \[\leadsto \frac{2}{\color{blue}{{x}^{6} \cdot \left(\frac{1}{360} + \frac{1}{12} \cdot \frac{1}{{x}^{2}}\right)}} \]
    9. Simplified87.1%

      \[\leadsto \frac{2}{\color{blue}{x \cdot \left(x \cdot \left(x \cdot \left(x \cdot \mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\right)\right)\right)\right)}} \]

    if 0.0 < (/.f64 #s(literal 2 binary64) (+.f64 (exp.f64 x) (exp.f64 (neg.f64 x))))

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{1 + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) - \frac{1}{2}\right)} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{{x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) - \frac{1}{2}\right) + 1} \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{2}, {x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) - \frac{1}{2}, 1\right)} \]
      3. unpow2N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, {x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) - \frac{1}{2}, 1\right) \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, {x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) - \frac{1}{2}, 1\right) \]
      5. sub-negN/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}, 1\right) \]
      6. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) + \color{blue}{\frac{-1}{2}}, 1\right) \]
      7. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}, \frac{-1}{2}\right)}, 1\right) \]
      8. unpow2N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}, \frac{-1}{2}\right), 1\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}, \frac{-1}{2}\right), 1\right) \]
      10. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-61}{720} \cdot {x}^{2} + \frac{5}{24}}, \frac{-1}{2}\right), 1\right) \]
      11. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-61}{720}} + \frac{5}{24}, \frac{-1}{2}\right), 1\right) \]
      12. unpow2N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{-61}{720} + \frac{5}{24}, \frac{-1}{2}\right), 1\right) \]
      13. associate-*l*N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(x \cdot \frac{-61}{720}\right)} + \frac{5}{24}, \frac{-1}{2}\right), 1\right) \]
      14. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, x \cdot \frac{-61}{720}, \frac{5}{24}\right)}, \frac{-1}{2}\right), 1\right) \]
      15. *-lowering-*.f6499.7

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot -0.08472222222222223}, 0.20833333333333334\right), -0.5\right), 1\right) \]
    5. Simplified99.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.08472222222222223, 0.20833333333333334\right), -0.5\right), 1\right)} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 3: 91.8% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;e^{x} + e^{-x} \leq 4:\\ \;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.08472222222222223, 0.20833333333333334\right), -0.5\right), 1\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{720}{\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= (+ (exp x) (exp (- x))) 4.0)
   (fma
    (* x x)
    (fma (* x x) (fma x (* x -0.08472222222222223) 0.20833333333333334) -0.5)
    1.0)
   (/ 720.0 (* (* x x) (* x (* x (* x x)))))))
double code(double x) {
	double tmp;
	if ((exp(x) + exp(-x)) <= 4.0) {
		tmp = fma((x * x), fma((x * x), fma(x, (x * -0.08472222222222223), 0.20833333333333334), -0.5), 1.0);
	} else {
		tmp = 720.0 / ((x * x) * (x * (x * (x * x))));
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (Float64(exp(x) + exp(Float64(-x))) <= 4.0)
		tmp = fma(Float64(x * x), fma(Float64(x * x), fma(x, Float64(x * -0.08472222222222223), 0.20833333333333334), -0.5), 1.0);
	else
		tmp = Float64(720.0 / Float64(Float64(x * x) * Float64(x * Float64(x * Float64(x * x)))));
	end
	return tmp
end
code[x_] := If[LessEqual[N[(N[Exp[x], $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision], 4.0], N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * -0.08472222222222223), $MachinePrecision] + 0.20833333333333334), $MachinePrecision] + -0.5), $MachinePrecision] + 1.0), $MachinePrecision], N[(720.0 / N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;e^{x} + e^{-x} \leq 4:\\
\;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.08472222222222223, 0.20833333333333334\right), -0.5\right), 1\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{720}{\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (exp.f64 x) (exp.f64 (neg.f64 x))) < 4

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{1 + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) - \frac{1}{2}\right)} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{{x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) - \frac{1}{2}\right) + 1} \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{2}, {x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) - \frac{1}{2}, 1\right)} \]
      3. unpow2N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, {x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) - \frac{1}{2}, 1\right) \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, {x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) - \frac{1}{2}, 1\right) \]
      5. sub-negN/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}, 1\right) \]
      6. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \left(\frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}\right) + \color{blue}{\frac{-1}{2}}, 1\right) \]
      7. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}, \frac{-1}{2}\right)}, 1\right) \]
      8. unpow2N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}, \frac{-1}{2}\right), 1\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{5}{24} + \frac{-61}{720} \cdot {x}^{2}, \frac{-1}{2}\right), 1\right) \]
      10. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-61}{720} \cdot {x}^{2} + \frac{5}{24}}, \frac{-1}{2}\right), 1\right) \]
      11. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-61}{720}} + \frac{5}{24}, \frac{-1}{2}\right), 1\right) \]
      12. unpow2N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{-61}{720} + \frac{5}{24}, \frac{-1}{2}\right), 1\right) \]
      13. associate-*l*N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(x \cdot \frac{-61}{720}\right)} + \frac{5}{24}, \frac{-1}{2}\right), 1\right) \]
      14. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, x \cdot \frac{-61}{720}, \frac{5}{24}\right)}, \frac{-1}{2}\right), 1\right) \]
      15. *-lowering-*.f6499.7

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot -0.08472222222222223}, 0.20833333333333334\right), -0.5\right), 1\right) \]
    5. Simplified99.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.08472222222222223, 0.20833333333333334\right), -0.5\right), 1\right)} \]

    if 4 < (+.f64 (exp.f64 x) (exp.f64 (neg.f64 x)))

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \frac{2}{\color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 2}} \]
      2. unpow2N/A

        \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right)} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 2} \]
      3. associate-*l*N/A

        \[\leadsto \frac{2}{\color{blue}{x \cdot \left(x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)} + 2} \]
      4. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right), 2\right)}} \]
    5. Simplified87.1%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot \mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\right), x\right), 2\right)}} \]
    6. Taylor expanded in x around inf

      \[\leadsto \color{blue}{\frac{720}{{x}^{6}}} \]
    7. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{720}{{x}^{6}}} \]
      2. metadata-evalN/A

        \[\leadsto \frac{720}{{x}^{\color{blue}{\left(5 + 1\right)}}} \]
      3. pow-plusN/A

        \[\leadsto \frac{720}{\color{blue}{{x}^{5} \cdot x}} \]
      4. metadata-evalN/A

        \[\leadsto \frac{720}{{x}^{\color{blue}{\left(4 + 1\right)}} \cdot x} \]
      5. pow-plusN/A

        \[\leadsto \frac{720}{\color{blue}{\left({x}^{4} \cdot x\right)} \cdot x} \]
      6. associate-*r*N/A

        \[\leadsto \frac{720}{\color{blue}{{x}^{4} \cdot \left(x \cdot x\right)}} \]
      7. unpow2N/A

        \[\leadsto \frac{720}{{x}^{4} \cdot \color{blue}{{x}^{2}}} \]
      8. *-commutativeN/A

        \[\leadsto \frac{720}{\color{blue}{{x}^{2} \cdot {x}^{4}}} \]
      9. *-lowering-*.f64N/A

        \[\leadsto \frac{720}{\color{blue}{{x}^{2} \cdot {x}^{4}}} \]
      10. unpow2N/A

        \[\leadsto \frac{720}{\color{blue}{\left(x \cdot x\right)} \cdot {x}^{4}} \]
      11. *-lowering-*.f64N/A

        \[\leadsto \frac{720}{\color{blue}{\left(x \cdot x\right)} \cdot {x}^{4}} \]
      12. metadata-evalN/A

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot {x}^{\color{blue}{\left(2 \cdot 2\right)}}} \]
      13. pow-sqrN/A

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot \color{blue}{\left({x}^{2} \cdot {x}^{2}\right)}} \]
      14. unpow2N/A

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot {x}^{2}\right)} \]
      15. associate-*l*N/A

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot \color{blue}{\left(x \cdot \left(x \cdot {x}^{2}\right)\right)}} \]
      16. unpow2N/A

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)} \]
      17. cube-multN/A

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot \left(x \cdot \color{blue}{{x}^{3}}\right)} \]
      18. *-lowering-*.f64N/A

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot \color{blue}{\left(x \cdot {x}^{3}\right)}} \]
      19. cube-multN/A

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot \left(x \cdot \color{blue}{\left(x \cdot \left(x \cdot x\right)\right)}\right)} \]
      20. unpow2N/A

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \color{blue}{{x}^{2}}\right)\right)} \]
      21. *-lowering-*.f64N/A

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot \left(x \cdot \color{blue}{\left(x \cdot {x}^{2}\right)}\right)} \]
      22. unpow2N/A

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)} \]
      23. *-lowering-*.f6487.1

        \[\leadsto \frac{720}{\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)} \]
    8. Simplified87.1%

      \[\leadsto \color{blue}{\frac{720}{\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 4: 87.6% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;e^{x} + e^{-x} \leq 4:\\ \;\;\;\;\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.20833333333333334, -0.5\right), 1\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= (+ (exp x) (exp (- x))) 4.0)
   (fma x (* x (fma (* x x) 0.20833333333333334 -0.5)) 1.0)
   (/ 24.0 (* x (* x (* x x))))))
double code(double x) {
	double tmp;
	if ((exp(x) + exp(-x)) <= 4.0) {
		tmp = fma(x, (x * fma((x * x), 0.20833333333333334, -0.5)), 1.0);
	} else {
		tmp = 24.0 / (x * (x * (x * x)));
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (Float64(exp(x) + exp(Float64(-x))) <= 4.0)
		tmp = fma(x, Float64(x * fma(Float64(x * x), 0.20833333333333334, -0.5)), 1.0);
	else
		tmp = Float64(24.0 / Float64(x * Float64(x * Float64(x * x))));
	end
	return tmp
end
code[x_] := If[LessEqual[N[(N[Exp[x], $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision], 4.0], N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * 0.20833333333333334 + -0.5), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision], N[(24.0 / N[(x * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;e^{x} + e^{-x} \leq 4:\\
\;\;\;\;\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.20833333333333334, -0.5\right), 1\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (exp.f64 x) (exp.f64 (neg.f64 x))) < 4

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{1 + {x}^{2} \cdot \left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right)} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right) + 1} \]
      2. unpow2N/A

        \[\leadsto \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right) + 1 \]
      3. associate-*l*N/A

        \[\leadsto \color{blue}{x \cdot \left(x \cdot \left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right)\right)} + 1 \]
      4. accelerator-lowering-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(x, x \cdot \left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right), 1\right)} \]
      5. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(x, \color{blue}{x \cdot \left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right)}, 1\right) \]
      6. sub-negN/A

        \[\leadsto \mathsf{fma}\left(x, x \cdot \color{blue}{\left(\frac{5}{24} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)}, 1\right) \]
      7. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(x, x \cdot \left(\color{blue}{{x}^{2} \cdot \frac{5}{24}} + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right), 1\right) \]
      8. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left(x, x \cdot \left({x}^{2} \cdot \frac{5}{24} + \color{blue}{\frac{-1}{2}}\right), 1\right) \]
      9. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(x, x \cdot \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{5}{24}, \frac{-1}{2}\right)}, 1\right) \]
      10. unpow2N/A

        \[\leadsto \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{5}{24}, \frac{-1}{2}\right), 1\right) \]
      11. *-lowering-*.f6499.6

        \[\leadsto \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, 0.20833333333333334, -0.5\right), 1\right) \]
    5. Simplified99.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.20833333333333334, -0.5\right), 1\right)} \]

    if 4 < (+.f64 (exp.f64 x) (exp.f64 (neg.f64 x)))

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

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

        \[\leadsto \frac{2}{\color{blue}{{x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2}} \]
      2. unpow2N/A

        \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right)} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2} \]
      3. associate-*l*N/A

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

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

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{x \cdot \left(\frac{1}{12} \cdot {x}^{2}\right) + x \cdot 1}, 2\right)} \]
      7. *-rgt-identityN/A

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, \frac{1}{12} \cdot {x}^{2}, x\right)}, 2\right)} \]
      9. *-commutativeN/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{{x}^{2} \cdot \frac{1}{12}}, x\right), 2\right)} \]
      10. *-lowering-*.f64N/A

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{1}{12}, x\right), 2\right)} \]
      12. *-lowering-*.f6475.8

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot 0.08333333333333333, x\right), 2\right)} \]
    5. Simplified75.8%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot 0.08333333333333333, x\right), 2\right)}} \]
    6. Taylor expanded in x around inf

      \[\leadsto \color{blue}{\frac{24}{{x}^{4}}} \]
    7. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{24}{{x}^{4}}} \]
      2. metadata-evalN/A

        \[\leadsto \frac{24}{{x}^{\color{blue}{\left(2 \cdot 2\right)}}} \]
      3. pow-sqrN/A

        \[\leadsto \frac{24}{\color{blue}{{x}^{2} \cdot {x}^{2}}} \]
      4. unpow2N/A

        \[\leadsto \frac{24}{\color{blue}{\left(x \cdot x\right)} \cdot {x}^{2}} \]
      5. associate-*l*N/A

        \[\leadsto \frac{24}{\color{blue}{x \cdot \left(x \cdot {x}^{2}\right)}} \]
      6. unpow2N/A

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)} \]
      7. cube-multN/A

        \[\leadsto \frac{24}{x \cdot \color{blue}{{x}^{3}}} \]
      8. *-lowering-*.f64N/A

        \[\leadsto \frac{24}{\color{blue}{x \cdot {x}^{3}}} \]
      9. cube-multN/A

        \[\leadsto \frac{24}{x \cdot \color{blue}{\left(x \cdot \left(x \cdot x\right)\right)}} \]
      10. unpow2N/A

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{{x}^{2}}\right)} \]
      11. *-lowering-*.f64N/A

        \[\leadsto \frac{24}{x \cdot \color{blue}{\left(x \cdot {x}^{2}\right)}} \]
      12. unpow2N/A

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)} \]
      13. *-lowering-*.f6476.5

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)} \]
    8. Simplified76.5%

      \[\leadsto \color{blue}{\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 5: 76.3% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\\ t_1 := x \cdot \left(x \cdot t\_0\right)\\ \mathbf{if}\;x \leq 1.5 \cdot 10^{+77}:\\ \;\;\;\;\frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \mathsf{fma}\left(t\_1, t\_1, -1\right), \frac{1}{\mathsf{fma}\left(x \cdot x, t\_0, -1\right)}, 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (fma (* x x) 0.002777777777777778 0.08333333333333333))
        (t_1 (* x (* x t_0))))
   (if (<= x 1.5e+77)
     (/
      2.0
      (fma (* (* x x) (fma t_1 t_1 -1.0)) (/ 1.0 (fma (* x x) t_0 -1.0)) 2.0))
     (/ 24.0 (* x (* x (* x x)))))))
double code(double x) {
	double t_0 = fma((x * x), 0.002777777777777778, 0.08333333333333333);
	double t_1 = x * (x * t_0);
	double tmp;
	if (x <= 1.5e+77) {
		tmp = 2.0 / fma(((x * x) * fma(t_1, t_1, -1.0)), (1.0 / fma((x * x), t_0, -1.0)), 2.0);
	} else {
		tmp = 24.0 / (x * (x * (x * x)));
	}
	return tmp;
}
function code(x)
	t_0 = fma(Float64(x * x), 0.002777777777777778, 0.08333333333333333)
	t_1 = Float64(x * Float64(x * t_0))
	tmp = 0.0
	if (x <= 1.5e+77)
		tmp = Float64(2.0 / fma(Float64(Float64(x * x) * fma(t_1, t_1, -1.0)), Float64(1.0 / fma(Float64(x * x), t_0, -1.0)), 2.0));
	else
		tmp = Float64(24.0 / Float64(x * Float64(x * Float64(x * x))));
	end
	return tmp
end
code[x_] := Block[{t$95$0 = N[(N[(x * x), $MachinePrecision] * 0.002777777777777778 + 0.08333333333333333), $MachinePrecision]}, Block[{t$95$1 = N[(x * N[(x * t$95$0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 1.5e+77], N[(2.0 / N[(N[(N[(x * x), $MachinePrecision] * N[(t$95$1 * t$95$1 + -1.0), $MachinePrecision]), $MachinePrecision] * N[(1.0 / N[(N[(x * x), $MachinePrecision] * t$95$0 + -1.0), $MachinePrecision]), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], N[(24.0 / N[(x * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\\
t_1 := x \cdot \left(x \cdot t\_0\right)\\
\mathbf{if}\;x \leq 1.5 \cdot 10^{+77}:\\
\;\;\;\;\frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \mathsf{fma}\left(t\_1, t\_1, -1\right), \frac{1}{\mathsf{fma}\left(x \cdot x, t\_0, -1\right)}, 2\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.4999999999999999e77

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \frac{2}{\color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 2}} \]
      2. unpow2N/A

        \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right)} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 2} \]
      3. associate-*l*N/A

        \[\leadsto \frac{2}{\color{blue}{x \cdot \left(x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)} + 2} \]
      4. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right), 2\right)}} \]
    5. Simplified92.0%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot \mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\right), x\right), 2\right)}} \]
    6. Step-by-step derivation
      1. distribute-rgt-inN/A

        \[\leadsto \frac{2}{\color{blue}{\left(\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)\right) \cdot x + x \cdot x\right)} + 2} \]
      2. associate-+l+N/A

        \[\leadsto \frac{2}{\color{blue}{\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)\right) \cdot x + \left(x \cdot x + 2\right)}} \]
      3. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right), x, x \cdot x + 2\right)}} \]
      4. *-lowering-*.f64N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\color{blue}{\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)}, x, x \cdot x + 2\right)} \]
      5. *-lowering-*.f64N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\color{blue}{\left(x \cdot x\right)} \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right), x, x \cdot x + 2\right)} \]
      6. *-lowering-*.f64N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \color{blue}{\left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)}, x, x \cdot x + 2\right)} \]
      7. associate-*r*N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(\color{blue}{\left(x \cdot x\right) \cdot \frac{1}{360}} + \frac{1}{12}\right)\right), x, x \cdot x + 2\right)} \]
      8. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \frac{1}{360}, \frac{1}{12}\right)}\right), x, x \cdot x + 2\right)} \]
      9. *-lowering-*.f64N/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{360}, \frac{1}{12}\right)\right), x, x \cdot x + 2\right)} \]
      10. accelerator-lowering-fma.f6492.0

        \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), x, \color{blue}{\mathsf{fma}\left(x, x, 2\right)}\right)} \]
    7. Applied egg-rr92.0%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), x, \mathsf{fma}\left(x, x, 2\right)\right)}} \]
    8. Step-by-step derivation
      1. associate-+r+N/A

        \[\leadsto \frac{2}{\color{blue}{\left(\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right)\right)\right) \cdot x + x \cdot x\right) + 2}} \]
      2. *-rgt-identityN/A

        \[\leadsto \frac{2}{\left(\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right)\right)\right) \cdot x + \color{blue}{\left(x \cdot x\right) \cdot 1}\right) + 2} \]
      3. associate-*l*N/A

        \[\leadsto \frac{2}{\left(\color{blue}{\left(x \cdot x\right) \cdot \left(\left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right)\right) \cdot x\right)} + \left(x \cdot x\right) \cdot 1\right) + 2} \]
      4. *-commutativeN/A

        \[\leadsto \frac{2}{\left(\left(x \cdot x\right) \cdot \color{blue}{\left(x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right)\right)\right)} + \left(x \cdot x\right) \cdot 1\right) + 2} \]
      5. distribute-lft-inN/A

        \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right)\right) + 1\right)} + 2} \]
      6. *-commutativeN/A

        \[\leadsto \frac{2}{\color{blue}{\left(x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right)\right) + 1\right) \cdot \left(x \cdot x\right)} + 2} \]
    9. Applied egg-rr69.3%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), -1\right) \cdot \left(x \cdot x\right), \frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right), -1\right)}, 2\right)}} \]

    if 1.4999999999999999e77 < x

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

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

        \[\leadsto \frac{2}{\color{blue}{{x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2}} \]
      2. unpow2N/A

        \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right)} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2} \]
      3. associate-*l*N/A

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

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

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{x \cdot \left(\frac{1}{12} \cdot {x}^{2}\right) + x \cdot 1}, 2\right)} \]
      7. *-rgt-identityN/A

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, \frac{1}{12} \cdot {x}^{2}, x\right)}, 2\right)} \]
      9. *-commutativeN/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{{x}^{2} \cdot \frac{1}{12}}, x\right), 2\right)} \]
      10. *-lowering-*.f64N/A

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{1}{12}, x\right), 2\right)} \]
      12. *-lowering-*.f64100.0

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot 0.08333333333333333, x\right), 2\right)} \]
    5. Simplified100.0%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot 0.08333333333333333, x\right), 2\right)}} \]
    6. Taylor expanded in x around inf

      \[\leadsto \color{blue}{\frac{24}{{x}^{4}}} \]
    7. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{24}{{x}^{4}}} \]
      2. metadata-evalN/A

        \[\leadsto \frac{24}{{x}^{\color{blue}{\left(2 \cdot 2\right)}}} \]
      3. pow-sqrN/A

        \[\leadsto \frac{24}{\color{blue}{{x}^{2} \cdot {x}^{2}}} \]
      4. unpow2N/A

        \[\leadsto \frac{24}{\color{blue}{\left(x \cdot x\right)} \cdot {x}^{2}} \]
      5. associate-*l*N/A

        \[\leadsto \frac{24}{\color{blue}{x \cdot \left(x \cdot {x}^{2}\right)}} \]
      6. unpow2N/A

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)} \]
      7. cube-multN/A

        \[\leadsto \frac{24}{x \cdot \color{blue}{{x}^{3}}} \]
      8. *-lowering-*.f64N/A

        \[\leadsto \frac{24}{\color{blue}{x \cdot {x}^{3}}} \]
      9. cube-multN/A

        \[\leadsto \frac{24}{x \cdot \color{blue}{\left(x \cdot \left(x \cdot x\right)\right)}} \]
      10. unpow2N/A

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{{x}^{2}}\right)} \]
      11. *-lowering-*.f64N/A

        \[\leadsto \frac{24}{x \cdot \color{blue}{\left(x \cdot {x}^{2}\right)}} \]
      12. unpow2N/A

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)} \]
      13. *-lowering-*.f64100.0

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)} \]
    8. Simplified100.0%

      \[\leadsto \color{blue}{\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification74.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1.5 \cdot 10^{+77}:\\ \;\;\;\;\frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), -1\right), \frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right), -1\right)}, 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 75.1% accurate, 2.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(x \cdot x, x \cdot 0.08333333333333333, x\right)\\ \mathbf{if}\;x \leq 1.5 \cdot 10^{+77}:\\ \;\;\;\;\frac{2}{\mathsf{fma}\left(x \cdot x, t\_0 \cdot t\_0, -4\right)} \cdot \mathsf{fma}\left(x, t\_0, -2\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (fma (* x x) (* x 0.08333333333333333) x)))
   (if (<= x 1.5e+77)
     (* (/ 2.0 (fma (* x x) (* t_0 t_0) -4.0)) (fma x t_0 -2.0))
     (/ 24.0 (* x (* x (* x x)))))))
double code(double x) {
	double t_0 = fma((x * x), (x * 0.08333333333333333), x);
	double tmp;
	if (x <= 1.5e+77) {
		tmp = (2.0 / fma((x * x), (t_0 * t_0), -4.0)) * fma(x, t_0, -2.0);
	} else {
		tmp = 24.0 / (x * (x * (x * x)));
	}
	return tmp;
}
function code(x)
	t_0 = fma(Float64(x * x), Float64(x * 0.08333333333333333), x)
	tmp = 0.0
	if (x <= 1.5e+77)
		tmp = Float64(Float64(2.0 / fma(Float64(x * x), Float64(t_0 * t_0), -4.0)) * fma(x, t_0, -2.0));
	else
		tmp = Float64(24.0 / Float64(x * Float64(x * Float64(x * x))));
	end
	return tmp
end
code[x_] := Block[{t$95$0 = N[(N[(x * x), $MachinePrecision] * N[(x * 0.08333333333333333), $MachinePrecision] + x), $MachinePrecision]}, If[LessEqual[x, 1.5e+77], N[(N[(2.0 / N[(N[(x * x), $MachinePrecision] * N[(t$95$0 * t$95$0), $MachinePrecision] + -4.0), $MachinePrecision]), $MachinePrecision] * N[(x * t$95$0 + -2.0), $MachinePrecision]), $MachinePrecision], N[(24.0 / N[(x * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(x \cdot x, x \cdot 0.08333333333333333, x\right)\\
\mathbf{if}\;x \leq 1.5 \cdot 10^{+77}:\\
\;\;\;\;\frac{2}{\mathsf{fma}\left(x \cdot x, t\_0 \cdot t\_0, -4\right)} \cdot \mathsf{fma}\left(x, t\_0, -2\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.4999999999999999e77

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

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

        \[\leadsto \frac{2}{\color{blue}{{x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2}} \]
      2. unpow2N/A

        \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right)} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2} \]
      3. associate-*l*N/A

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

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

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{x \cdot \left(\frac{1}{12} \cdot {x}^{2}\right) + x \cdot 1}, 2\right)} \]
      7. *-rgt-identityN/A

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, \frac{1}{12} \cdot {x}^{2}, x\right)}, 2\right)} \]
      9. *-commutativeN/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{{x}^{2} \cdot \frac{1}{12}}, x\right), 2\right)} \]
      10. *-lowering-*.f64N/A

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{1}{12}, x\right), 2\right)} \]
      12. *-lowering-*.f6484.9

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot 0.08333333333333333, x\right), 2\right)} \]
    5. Simplified84.9%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot 0.08333333333333333, x\right), 2\right)}} \]
    6. Step-by-step derivation
      1. flip-+N/A

        \[\leadsto \frac{2}{\color{blue}{\frac{\left(x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) + x\right)\right) \cdot \left(x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) + x\right)\right) - 2 \cdot 2}{x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) + x\right) - 2}}} \]
      2. associate-/r/N/A

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

        \[\leadsto \color{blue}{\frac{2}{\left(x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) + x\right)\right) \cdot \left(x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) + x\right)\right) - 2 \cdot 2} \cdot \left(x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) + x\right) - 2\right)} \]
    7. Applied egg-rr67.8%

      \[\leadsto \color{blue}{\frac{2}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, x \cdot 0.08333333333333333, x\right) \cdot \mathsf{fma}\left(x \cdot x, x \cdot 0.08333333333333333, x\right), -4\right)} \cdot \mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot 0.08333333333333333, x\right), -2\right)} \]

    if 1.4999999999999999e77 < x

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

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

        \[\leadsto \frac{2}{\color{blue}{{x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2}} \]
      2. unpow2N/A

        \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right)} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2} \]
      3. associate-*l*N/A

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

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

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{x \cdot \left(\frac{1}{12} \cdot {x}^{2}\right) + x \cdot 1}, 2\right)} \]
      7. *-rgt-identityN/A

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, \frac{1}{12} \cdot {x}^{2}, x\right)}, 2\right)} \]
      9. *-commutativeN/A

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{{x}^{2} \cdot \frac{1}{12}}, x\right), 2\right)} \]
      10. *-lowering-*.f64N/A

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{1}{12}, x\right), 2\right)} \]
      12. *-lowering-*.f64100.0

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot 0.08333333333333333, x\right), 2\right)} \]
    5. Simplified100.0%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot 0.08333333333333333, x\right), 2\right)}} \]
    6. Taylor expanded in x around inf

      \[\leadsto \color{blue}{\frac{24}{{x}^{4}}} \]
    7. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{24}{{x}^{4}}} \]
      2. metadata-evalN/A

        \[\leadsto \frac{24}{{x}^{\color{blue}{\left(2 \cdot 2\right)}}} \]
      3. pow-sqrN/A

        \[\leadsto \frac{24}{\color{blue}{{x}^{2} \cdot {x}^{2}}} \]
      4. unpow2N/A

        \[\leadsto \frac{24}{\color{blue}{\left(x \cdot x\right)} \cdot {x}^{2}} \]
      5. associate-*l*N/A

        \[\leadsto \frac{24}{\color{blue}{x \cdot \left(x \cdot {x}^{2}\right)}} \]
      6. unpow2N/A

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)} \]
      7. cube-multN/A

        \[\leadsto \frac{24}{x \cdot \color{blue}{{x}^{3}}} \]
      8. *-lowering-*.f64N/A

        \[\leadsto \frac{24}{\color{blue}{x \cdot {x}^{3}}} \]
      9. cube-multN/A

        \[\leadsto \frac{24}{x \cdot \color{blue}{\left(x \cdot \left(x \cdot x\right)\right)}} \]
      10. unpow2N/A

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{{x}^{2}}\right)} \]
      11. *-lowering-*.f64N/A

        \[\leadsto \frac{24}{x \cdot \color{blue}{\left(x \cdot {x}^{2}\right)}} \]
      12. unpow2N/A

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)} \]
      13. *-lowering-*.f64100.0

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)} \]
    8. Simplified100.0%

      \[\leadsto \color{blue}{\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 7: 91.8% accurate, 4.3× speedup?

\[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), x, \mathsf{fma}\left(x, x, 2\right)\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  2.0
  (fma
   (* (* x x) (* x (fma (* x x) 0.002777777777777778 0.08333333333333333)))
   x
   (fma x x 2.0))))
double code(double x) {
	return 2.0 / fma(((x * x) * (x * fma((x * x), 0.002777777777777778, 0.08333333333333333))), x, fma(x, x, 2.0));
}
function code(x)
	return Float64(2.0 / fma(Float64(Float64(x * x) * Float64(x * fma(Float64(x * x), 0.002777777777777778, 0.08333333333333333))), x, fma(x, x, 2.0)))
end
code[x_] := N[(2.0 / N[(N[(N[(x * x), $MachinePrecision] * N[(x * N[(N[(x * x), $MachinePrecision] * 0.002777777777777778 + 0.08333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * x + N[(x * x + 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), x, \mathsf{fma}\left(x, x, 2\right)\right)}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{2}{e^{x} + e^{-x}} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
  4. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \frac{2}{\color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 2}} \]
    2. unpow2N/A

      \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right)} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 2} \]
    3. associate-*l*N/A

      \[\leadsto \frac{2}{\color{blue}{x \cdot \left(x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)} + 2} \]
    4. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right), 2\right)}} \]
  5. Simplified93.3%

    \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot \mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\right), x\right), 2\right)}} \]
  6. Step-by-step derivation
    1. distribute-rgt-inN/A

      \[\leadsto \frac{2}{\color{blue}{\left(\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)\right) \cdot x + x \cdot x\right)} + 2} \]
    2. associate-+l+N/A

      \[\leadsto \frac{2}{\color{blue}{\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)\right) \cdot x + \left(x \cdot x + 2\right)}} \]
    3. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right), x, x \cdot x + 2\right)}} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(\color{blue}{\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)}, x, x \cdot x + 2\right)} \]
    5. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(\color{blue}{\left(x \cdot x\right)} \cdot \left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right), x, x \cdot x + 2\right)} \]
    6. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \color{blue}{\left(x \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)\right)}, x, x \cdot x + 2\right)} \]
    7. associate-*r*N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(\color{blue}{\left(x \cdot x\right) \cdot \frac{1}{360}} + \frac{1}{12}\right)\right), x, x \cdot x + 2\right)} \]
    8. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \color{blue}{\mathsf{fma}\left(x \cdot x, \frac{1}{360}, \frac{1}{12}\right)}\right), x, x \cdot x + 2\right)} \]
    9. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{360}, \frac{1}{12}\right)\right), x, x \cdot x + 2\right)} \]
    10. accelerator-lowering-fma.f6493.3

      \[\leadsto \frac{2}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), x, \color{blue}{\mathsf{fma}\left(x, x, 2\right)}\right)} \]
  7. Applied egg-rr93.3%

    \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(\left(x \cdot x\right) \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right)\right), x, \mathsf{fma}\left(x, x, 2\right)\right)}} \]
  8. Add Preprocessing

Alternative 8: 91.8% accurate, 4.8× speedup?

\[\begin{array}{l} \\ \frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.001388888888888889, 0.041666666666666664\right), 0.5\right), 1\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  1.0
  (fma
   (* x x)
   (fma (* x x) (fma x (* x 0.001388888888888889) 0.041666666666666664) 0.5)
   1.0)))
double code(double x) {
	return 1.0 / fma((x * x), fma((x * x), fma(x, (x * 0.001388888888888889), 0.041666666666666664), 0.5), 1.0);
}
function code(x)
	return Float64(1.0 / fma(Float64(x * x), fma(Float64(x * x), fma(x, Float64(x * 0.001388888888888889), 0.041666666666666664), 0.5), 1.0))
end
code[x_] := N[(1.0 / N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * 0.001388888888888889), $MachinePrecision] + 0.041666666666666664), $MachinePrecision] + 0.5), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.001388888888888889, 0.041666666666666664\right), 0.5\right), 1\right)}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{2}{e^{x} + e^{-x}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. clear-numN/A

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

      \[\leadsto \frac{1}{\color{blue}{\cosh x}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
    4. cosh-lowering-cosh.f64100.0

      \[\leadsto \frac{1}{\color{blue}{\cosh x}} \]
  4. Applied egg-rr100.0%

    \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
  5. Taylor expanded in x around 0

    \[\leadsto \frac{1}{\color{blue}{1 + {x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}} \]
  6. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \frac{1}{\color{blue}{{x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + 1}} \]
    2. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right), 1\right)}} \]
    3. unpow2N/A

      \[\leadsto \frac{1}{\mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right), 1\right)} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \frac{1}{\mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right), 1\right)} \]
    5. +-commutativeN/A

      \[\leadsto \frac{1}{\mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \frac{1}{2}}, 1\right)} \]
    6. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{1}{\mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{1}{24} + \frac{1}{720} \cdot {x}^{2}, \frac{1}{2}\right)}, 1\right)} \]
    7. unpow2N/A

      \[\leadsto \frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + \frac{1}{720} \cdot {x}^{2}, \frac{1}{2}\right), 1\right)} \]
    8. *-lowering-*.f64N/A

      \[\leadsto \frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{1}{24} + \frac{1}{720} \cdot {x}^{2}, \frac{1}{2}\right), 1\right)} \]
    9. +-commutativeN/A

      \[\leadsto \frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{1}{720} \cdot {x}^{2} + \frac{1}{24}}, \frac{1}{2}\right), 1\right)} \]
    10. *-commutativeN/A

      \[\leadsto \frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{1}{720}} + \frac{1}{24}, \frac{1}{2}\right), 1\right)} \]
    11. unpow2N/A

      \[\leadsto \frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{1}{720} + \frac{1}{24}, \frac{1}{2}\right), 1\right)} \]
    12. associate-*l*N/A

      \[\leadsto \frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot \left(x \cdot \frac{1}{720}\right)} + \frac{1}{24}, \frac{1}{2}\right), 1\right)} \]
    13. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left(x, x \cdot \frac{1}{720}, \frac{1}{24}\right)}, \frac{1}{2}\right), 1\right)} \]
    14. *-lowering-*.f6493.3

      \[\leadsto \frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot 0.001388888888888889}, 0.041666666666666664\right), 0.5\right), 1\right)} \]
  7. Simplified93.3%

    \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot 0.001388888888888889, 0.041666666666666664\right), 0.5\right), 1\right)}} \]
  8. Add Preprocessing

Alternative 9: 91.4% accurate, 5.0× speedup?

\[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot 0.002777777777777778\right)\right), 2\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/ 2.0 (fma x (* (* x x) (* x (* (* x x) 0.002777777777777778))) 2.0)))
double code(double x) {
	return 2.0 / fma(x, ((x * x) * (x * ((x * x) * 0.002777777777777778))), 2.0);
}
function code(x)
	return Float64(2.0 / fma(x, Float64(Float64(x * x) * Float64(x * Float64(Float64(x * x) * 0.002777777777777778))), 2.0))
end
code[x_] := N[(2.0 / N[(x * N[(N[(x * x), $MachinePrecision] * N[(x * N[(N[(x * x), $MachinePrecision] * 0.002777777777777778), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot 0.002777777777777778\right)\right), 2\right)}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{2}{e^{x} + e^{-x}} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
  4. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \frac{2}{\color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 2}} \]
    2. unpow2N/A

      \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right)} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 2} \]
    3. associate-*l*N/A

      \[\leadsto \frac{2}{\color{blue}{x \cdot \left(x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)} + 2} \]
    4. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right), 2\right)}} \]
  5. Simplified93.3%

    \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot \mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\right), x\right), 2\right)}} \]
  6. Taylor expanded in x around inf

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\frac{1}{360} \cdot {x}^{5}}, 2\right)} \]
  7. Step-by-step derivation
    1. metadata-evalN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \frac{1}{360} \cdot {x}^{\color{blue}{\left(4 + 1\right)}}, 2\right)} \]
    2. pow-plusN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \frac{1}{360} \cdot \color{blue}{\left({x}^{4} \cdot x\right)}, 2\right)} \]
    3. associate-*l*N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(\frac{1}{360} \cdot {x}^{4}\right) \cdot x}, 2\right)} \]
    4. metadata-evalN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \left(\frac{1}{360} \cdot {x}^{\color{blue}{\left(2 \cdot 2\right)}}\right) \cdot x, 2\right)} \]
    5. pow-sqrN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \left(\frac{1}{360} \cdot \color{blue}{\left({x}^{2} \cdot {x}^{2}\right)}\right) \cdot x, 2\right)} \]
    6. associate-*r*N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(\left(\frac{1}{360} \cdot {x}^{2}\right) \cdot {x}^{2}\right)} \cdot x, 2\right)} \]
    7. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{360} \cdot {x}^{2}\right)\right)} \cdot x, 2\right)} \]
    8. associate-*l*N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{{x}^{2} \cdot \left(\left(\frac{1}{360} \cdot {x}^{2}\right) \cdot x\right)}, 2\right)} \]
    9. associate-*r*N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, {x}^{2} \cdot \color{blue}{\left(\frac{1}{360} \cdot \left({x}^{2} \cdot x\right)\right)}, 2\right)} \]
    10. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, {x}^{2} \cdot \left(\frac{1}{360} \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot x\right)\right), 2\right)} \]
    11. unpow3N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, {x}^{2} \cdot \left(\frac{1}{360} \cdot \color{blue}{{x}^{3}}\right), 2\right)} \]
    12. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{{x}^{2} \cdot \left(\frac{1}{360} \cdot {x}^{3}\right)}, 2\right)} \]
    13. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{1}{360} \cdot {x}^{3}\right), 2\right)} \]
    14. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{1}{360} \cdot {x}^{3}\right), 2\right)} \]
    15. unpow3N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(\frac{1}{360} \cdot \color{blue}{\left(\left(x \cdot x\right) \cdot x\right)}\right), 2\right)} \]
    16. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(\frac{1}{360} \cdot \left(\color{blue}{{x}^{2}} \cdot x\right)\right), 2\right)} \]
    17. associate-*r*N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \color{blue}{\left(\left(\frac{1}{360} \cdot {x}^{2}\right) \cdot x\right)}, 2\right)} \]
    18. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \color{blue}{\left(x \cdot \left(\frac{1}{360} \cdot {x}^{2}\right)\right)}, 2\right)} \]
    19. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \color{blue}{\left(x \cdot \left(\frac{1}{360} \cdot {x}^{2}\right)\right)}, 2\right)} \]
    20. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(x \cdot \color{blue}{\left({x}^{2} \cdot \frac{1}{360}\right)}\right), 2\right)} \]
    21. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(x \cdot \color{blue}{\left({x}^{2} \cdot \frac{1}{360}\right)}\right), 2\right)} \]
    22. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(x \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \frac{1}{360}\right)\right), 2\right)} \]
    23. *-lowering-*.f6492.9

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot \left(x \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot 0.002777777777777778\right)\right), 2\right)} \]
  8. Simplified92.9%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right) \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot 0.002777777777777778\right)\right)}, 2\right)} \]
  9. Add Preprocessing

Alternative 10: 87.6% accurate, 6.4× speedup?

\[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot 0.08333333333333333, x\right), 2\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/ 2.0 (fma x (fma x (* (* x x) 0.08333333333333333) x) 2.0)))
double code(double x) {
	return 2.0 / fma(x, fma(x, ((x * x) * 0.08333333333333333), x), 2.0);
}
function code(x)
	return Float64(2.0 / fma(x, fma(x, Float64(Float64(x * x) * 0.08333333333333333), x), 2.0))
end
code[x_] := N[(2.0 / N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * 0.08333333333333333), $MachinePrecision] + x), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot 0.08333333333333333, x\right), 2\right)}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{2}{e^{x} + e^{-x}} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

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

      \[\leadsto \frac{2}{\color{blue}{{x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2}} \]
    2. unpow2N/A

      \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right)} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2} \]
    3. associate-*l*N/A

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

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

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{x \cdot \left(\frac{1}{12} \cdot {x}^{2}\right) + x \cdot 1}, 2\right)} \]
    7. *-rgt-identityN/A

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, \frac{1}{12} \cdot {x}^{2}, x\right)}, 2\right)} \]
    9. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{{x}^{2} \cdot \frac{1}{12}}, x\right), 2\right)} \]
    10. *-lowering-*.f64N/A

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{1}{12}, x\right), 2\right)} \]
    12. *-lowering-*.f6487.4

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot 0.08333333333333333, x\right), 2\right)} \]
  5. Simplified87.4%

    \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot 0.08333333333333333, x\right), 2\right)}} \]
  6. Add Preprocessing

Alternative 11: 63.3% accurate, 9.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.25:\\ \;\;\;\;\mathsf{fma}\left(-0.5, x \cdot x, 1\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{2}{x \cdot x}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 1.25) (fma -0.5 (* x x) 1.0) (/ 2.0 (* x x))))
double code(double x) {
	double tmp;
	if (x <= 1.25) {
		tmp = fma(-0.5, (x * x), 1.0);
	} else {
		tmp = 2.0 / (x * x);
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= 1.25)
		tmp = fma(-0.5, Float64(x * x), 1.0);
	else
		tmp = Float64(2.0 / Float64(x * x));
	end
	return tmp
end
code[x_] := If[LessEqual[x, 1.25], N[(-0.5 * N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision], N[(2.0 / N[(x * x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 1.25:\\
\;\;\;\;\mathsf{fma}\left(-0.5, x \cdot x, 1\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{2}{x \cdot x}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.25

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{1 + \frac{-1}{2} \cdot {x}^{2}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

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

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

        \[\leadsto \mathsf{fma}\left(\frac{-1}{2}, \color{blue}{x \cdot x}, 1\right) \]
      4. *-lowering-*.f6463.0

        \[\leadsto \mathsf{fma}\left(-0.5, \color{blue}{x \cdot x}, 1\right) \]
    5. Simplified63.0%

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

    if 1.25 < x

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2}}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \frac{2}{\color{blue}{{x}^{2} + 2}} \]
      2. unpow2N/A

        \[\leadsto \frac{2}{\color{blue}{x \cdot x} + 2} \]
      3. accelerator-lowering-fma.f6454.1

        \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x, 2\right)}} \]
    5. Simplified54.1%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x, 2\right)}} \]
    6. Taylor expanded in x around inf

      \[\leadsto \color{blue}{\frac{2}{{x}^{2}}} \]
    7. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{2}{{x}^{2}}} \]
      2. unpow2N/A

        \[\leadsto \frac{2}{\color{blue}{x \cdot x}} \]
      3. *-lowering-*.f6454.1

        \[\leadsto \frac{2}{\color{blue}{x \cdot x}} \]
    8. Simplified54.1%

      \[\leadsto \color{blue}{\frac{2}{x \cdot x}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 12: 75.8% accurate, 12.1× speedup?

\[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, x, 2\right)} \end{array} \]
(FPCore (x) :precision binary64 (/ 2.0 (fma x x 2.0)))
double code(double x) {
	return 2.0 / fma(x, x, 2.0);
}
function code(x)
	return Float64(2.0 / fma(x, x, 2.0))
end
code[x_] := N[(2.0 / N[(x * x + 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{\mathsf{fma}\left(x, x, 2\right)}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{2}{e^{x} + e^{-x}} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2}}} \]
  4. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \frac{2}{\color{blue}{{x}^{2} + 2}} \]
    2. unpow2N/A

      \[\leadsto \frac{2}{\color{blue}{x \cdot x} + 2} \]
    3. accelerator-lowering-fma.f6476.8

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x, 2\right)}} \]
  5. Simplified76.8%

    \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x, 2\right)}} \]
  6. Add Preprocessing

Alternative 13: 51.0% accurate, 217.0× speedup?

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

\\
1
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{2}{e^{x} + e^{-x}} \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{1} \]
  4. Step-by-step derivation
    1. Simplified49.6%

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

    Reproduce

    ?
    herbie shell --seed 2024198 
    (FPCore (x)
      :name "Hyperbolic secant"
      :precision binary64
      (/ 2.0 (+ (exp x) (exp (- x)))))