Hyperbolic secant

Percentage Accurate: 100.0% → 100.0%
Time: 10.4s
Alternatives: 18
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 18 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: 91.2% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;e^{x} + e^{-x} \leq 4:\\ \;\;\;\;\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot -0.08472222222222223, 0.20833333333333334\right), -0.5\right), 1\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{720}{x \cdot \left(x \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)}\\ \end{array} \end{array} \]
(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(x * Float64(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[(x * N[(x * N[(x * N[(x * N[(x * x), $MachinePrecision]), $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}{x \cdot \left(x \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\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-*.f6499.8

        \[\leadsto \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, \color{blue}{x \cdot -0.08472222222222223}, 0.20833333333333334\right), -0.5\right), 1\right) \]
    5. Simplified99.8%

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

    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. Simplified82.0%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot \left(x \cdot x\right), \frac{1}{360}, \color{blue}{x \cdot \frac{1}{12}}\right), x\right), 2\right)} \]
      11. *-lowering-*.f6482.0

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot \left(x \cdot x\right), 0.002777777777777778, \color{blue}{x \cdot 0.08333333333333333}\right), x\right), 2\right)} \]
    7. Applied egg-rr82.0%

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

      \[\leadsto \color{blue}{\frac{720}{{x}^{6}}} \]
    9. 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. unpow2N/A

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

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

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

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

        \[\leadsto \frac{720}{x \cdot {x}^{\color{blue}{5}}} \]
      14. *-lowering-*.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \frac{720}{x \cdot \left(x \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)\right)} \]
      30. *-lowering-*.f6482.0

        \[\leadsto \frac{720}{x \cdot \left(x \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)\right)} \]
    10. Simplified82.0%

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

Alternative 3: 87.3% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;e^{x} + e^{-x} \leq 4:\\ \;\;\;\;\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.20833333333333334, -0.5\right), 1\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{2}{x \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot 0.08333333333333333, x\right)}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= (+ (exp x) (exp (- x))) 4.0)
   (fma x (* x (fma (* x x) 0.20833333333333334 -0.5)) 1.0)
   (/ 2.0 (* x (fma x (* (* x x) 0.08333333333333333) 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 = 2.0 / (x * fma(x, ((x * x) * 0.08333333333333333), 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(2.0 / Float64(x * fma(x, Float64(Float64(x * x) * 0.08333333333333333), 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[(2.0 / N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * 0.08333333333333333), $MachinePrecision] + x), $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{2}{x \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot 0.08333333333333333, x\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-*.f6499.7

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

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

    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-*.f6477.0

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot 0.08333333333333333, x\right), 2\right)} \]
    5. Simplified77.0%

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

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

        \[\leadsto \frac{2}{\color{blue}{{x}^{4} \cdot \frac{1}{12} + {x}^{4} \cdot \frac{1}{{x}^{2}}}} \]
      2. *-commutativeN/A

        \[\leadsto \frac{2}{\color{blue}{\frac{1}{12} \cdot {x}^{4}} + {x}^{4} \cdot \frac{1}{{x}^{2}}} \]
      3. metadata-evalN/A

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

        \[\leadsto \frac{2}{\frac{1}{12} \cdot \color{blue}{\left({x}^{2} \cdot {x}^{2}\right)} + {x}^{4} \cdot \frac{1}{{x}^{2}}} \]
      5. associate-*l*N/A

        \[\leadsto \frac{2}{\color{blue}{\left(\frac{1}{12} \cdot {x}^{2}\right) \cdot {x}^{2}} + {x}^{4} \cdot \frac{1}{{x}^{2}}} \]
      6. associate-*r/N/A

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

        \[\leadsto \frac{2}{\left(\frac{1}{12} \cdot {x}^{2}\right) \cdot {x}^{2} + \frac{\color{blue}{{x}^{4}}}{{x}^{2}}} \]
      8. metadata-evalN/A

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

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

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

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

        \[\leadsto \frac{2}{\left(\frac{1}{12} \cdot {x}^{2}\right) \cdot {x}^{2} + {x}^{2} \cdot \color{blue}{\left({x}^{2} \cdot \frac{1}{{x}^{2}}\right)}} \]
      13. rgt-mult-inverseN/A

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

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

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

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

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

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

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

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

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

        \[\leadsto \frac{2}{x \cdot \left(x \cdot \left(\frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{x}\right)} \]
    8. Simplified77.0%

      \[\leadsto \frac{2}{\color{blue}{x \cdot \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot 0.08333333333333333, x\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 4: 87.3% 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-*.f6499.7

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

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

    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-*.f6477.0

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot 0.08333333333333333, x\right), 2\right)} \]
    5. Simplified77.0%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot 0.08333333333333333, x\right), 2\right)}} \]
    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-*.f6477.0

        \[\leadsto \frac{24}{x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)} \]
    8. Simplified77.0%

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

Alternative 5: 75.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;e^{x} + e^{-x} \leq 4:\\ \;\;\;\;\mathsf{fma}\left(-0.5, x \cdot x, 1\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{2}{x \cdot x}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= (+ (exp x) (exp (- x))) 4.0) (fma -0.5 (* x x) 1.0) (/ 2.0 (* x x))))
double code(double x) {
	double tmp;
	if ((exp(x) + exp(-x)) <= 4.0) {
		tmp = fma(-0.5, (x * x), 1.0);
	} else {
		tmp = 2.0 / (x * x);
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (Float64(exp(x) + exp(Float64(-x))) <= 4.0)
		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[N[(N[Exp[x], $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision], 4.0], 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}\;e^{x} + e^{-x} \leq 4:\\
\;\;\;\;\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 (+.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

      \[\leadsto \color{blue}{1 + \frac{-1}{2} \cdot {x}^{2}} \]
    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-*.f6499.6

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

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

    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

      \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2}}} \]
    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.f6452.8

        \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x, 2\right)}} \]
    5. Simplified52.8%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x, 2\right)}} \]
    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-*.f6452.8

        \[\leadsto \frac{2}{\color{blue}{x \cdot x}} \]
    8. Simplified52.8%

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

Alternative 6: 96.1% accurate, 2.3× speedup?

\[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \left(\left(x \cdot x\right) \cdot \mathsf{fma}\left(x, \left(x \cdot \left(x \cdot x\right)\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), -12\right), x\right), 2\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  2.0
  (fma
   x
   (fma
    x
    (*
     (*
      (* x x)
      (fma x (* (* x (* x x)) 7.71604938271605e-6) -0.006944444444444444))
     (fma
      (* x x)
      (fma
       x
       (* x (fma (* x x) -0.00044444444444444447 -0.013333333333333334))
       -0.4)
      -12.0))
    x)
   2.0)))
double code(double x) {
	return 2.0 / fma(x, fma(x, (((x * x) * fma(x, ((x * (x * x)) * 7.71604938271605e-6), -0.006944444444444444)) * fma((x * x), fma(x, (x * fma((x * x), -0.00044444444444444447, -0.013333333333333334)), -0.4), -12.0)), x), 2.0);
}
function code(x)
	return Float64(2.0 / fma(x, fma(x, Float64(Float64(Float64(x * x) * fma(x, Float64(Float64(x * Float64(x * x)) * 7.71604938271605e-6), -0.006944444444444444)) * fma(Float64(x * x), fma(x, Float64(x * fma(Float64(x * x), -0.00044444444444444447, -0.013333333333333334)), -0.4), -12.0)), x), 2.0))
end
code[x_] := N[(2.0 / N[(x * N[(x * N[(N[(N[(x * x), $MachinePrecision] * N[(x * N[(N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] * 7.71604938271605e-6), $MachinePrecision] + -0.006944444444444444), $MachinePrecision]), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * -0.00044444444444444447 + -0.013333333333333334), $MachinePrecision]), $MachinePrecision] + -0.4), $MachinePrecision] + -12.0), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \left(\left(x \cdot x\right) \cdot \mathsf{fma}\left(x, \left(x \cdot \left(x \cdot x\right)\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), -12\right), 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

    \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
  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. Simplified90.4%

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(\left(x \cdot x\right) \cdot x\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)} + x, 2\right)} \]
    2. pow3N/A

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

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

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

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left({x}^{3} \cdot \left(\left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) - \frac{1}{12} \cdot \frac{1}{12}\right), \frac{1}{x \cdot \left(x \cdot \frac{1}{360}\right) - \frac{1}{12}}, x\right)}, 2\right)} \]
  7. Applied egg-rr66.0%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \frac{1}{\mathsf{fma}\left(x, x \cdot 0.002777777777777778, -0.08333333333333333\right)}, x\right)}, 2\right)} \]
  8. Taylor expanded in x around 0

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{{x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}\right) - 12}, x\right), 2\right)} \]
  9. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{{x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}\right) + \left(\mathsf{neg}\left(12\right)\right)}, x\right), 2\right)} \]
    2. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{\mathsf{fma}\left({x}^{2}, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}, \mathsf{neg}\left(12\right)\right)}, x\right), 2\right)} \]
    3. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(\color{blue}{x \cdot x}, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(\color{blue}{x \cdot x}, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    5. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) + \left(\mathsf{neg}\left(\frac{2}{5}\right)\right)}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    6. metadata-evalN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) + \color{blue}{\frac{-2}{5}}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    7. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}, \frac{-2}{5}\right)}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    8. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    9. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    10. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-1}{2250} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{75}\right)\right)}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    11. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-1}{2250}} + \left(\mathsf{neg}\left(\frac{1}{75}\right)\right), \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    12. metadata-evalN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \frac{-1}{2250} + \color{blue}{\frac{-1}{75}}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    13. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-1}{2250}, \frac{-1}{75}\right)}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    14. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    15. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    16. metadata-eval95.6

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), \color{blue}{-12}\right), x\right), 2\right)} \]
  10. Simplified95.6%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), -12\right)}, x\right), 2\right)} \]
  11. Step-by-step derivation
    1. associate-*l*N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(x \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{129600}\right) + \frac{-1}{144}\right)\right)\right)} \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{-1}{2250} + \frac{-1}{75}\right) + \frac{-2}{5}\right) + -12\right) + x, 2\right)} \]
    2. associate-*l*N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{x \cdot \left(\left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{129600}\right) + \frac{-1}{144}\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{-1}{2250} + \frac{-1}{75}\right) + \frac{-2}{5}\right) + -12\right)\right)} + x, 2\right)} \]
    3. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{129600}\right) + \frac{-1}{144}\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{-1}{2250} + \frac{-1}{75}\right) + \frac{-2}{5}\right) + -12\right), x\right)}, 2\right)} \]
  12. Applied egg-rr95.6%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, \left(\left(x \cdot x\right) \cdot \mathsf{fma}\left(x, \left(x \cdot \left(x \cdot x\right)\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), -12\right), x\right)}, 2\right)} \]
  13. Add Preprocessing

Alternative 7: 96.1% accurate, 2.4× speedup?

\[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot -0.00044444444444444447, -0.4\right), -12\right), x\right), 2\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  2.0
  (fma
   x
   (fma
    (*
     (* x (* x x))
     (fma (* x x) (* (* x x) 7.71604938271605e-6) -0.006944444444444444))
    (fma (* x x) (fma (* x x) (* (* x x) -0.00044444444444444447) -0.4) -12.0)
    x)
   2.0)))
double code(double x) {
	return 2.0 / fma(x, fma(((x * (x * x)) * fma((x * x), ((x * x) * 7.71604938271605e-6), -0.006944444444444444)), fma((x * x), fma((x * x), ((x * x) * -0.00044444444444444447), -0.4), -12.0), x), 2.0);
}
function code(x)
	return Float64(2.0 / fma(x, fma(Float64(Float64(x * Float64(x * x)) * fma(Float64(x * x), Float64(Float64(x * x) * 7.71604938271605e-6), -0.006944444444444444)), fma(Float64(x * x), fma(Float64(x * x), Float64(Float64(x * x) * -0.00044444444444444447), -0.4), -12.0), x), 2.0))
end
code[x_] := N[(2.0 / N[(x * N[(N[(N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 7.71604938271605e-6), $MachinePrecision] + -0.006944444444444444), $MachinePrecision]), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * -0.00044444444444444447), $MachinePrecision] + -0.4), $MachinePrecision] + -12.0), $MachinePrecision] + x), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot -0.00044444444444444447, -0.4\right), -12\right), 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

    \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
  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. Simplified90.4%

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(\left(x \cdot x\right) \cdot x\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)} + x, 2\right)} \]
    2. pow3N/A

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

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

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

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left({x}^{3} \cdot \left(\left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) - \frac{1}{12} \cdot \frac{1}{12}\right), \frac{1}{x \cdot \left(x \cdot \frac{1}{360}\right) - \frac{1}{12}}, x\right)}, 2\right)} \]
  7. Applied egg-rr66.0%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \frac{1}{\mathsf{fma}\left(x, x \cdot 0.002777777777777778, -0.08333333333333333\right)}, x\right)}, 2\right)} \]
  8. Taylor expanded in x around 0

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{{x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}\right) - 12}, x\right), 2\right)} \]
  9. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{{x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}\right) + \left(\mathsf{neg}\left(12\right)\right)}, x\right), 2\right)} \]
    2. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{\mathsf{fma}\left({x}^{2}, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}, \mathsf{neg}\left(12\right)\right)}, x\right), 2\right)} \]
    3. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(\color{blue}{x \cdot x}, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(\color{blue}{x \cdot x}, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    5. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) + \left(\mathsf{neg}\left(\frac{2}{5}\right)\right)}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    6. metadata-evalN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) + \color{blue}{\frac{-2}{5}}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    7. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}, \frac{-2}{5}\right)}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    8. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    9. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    10. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-1}{2250} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{75}\right)\right)}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    11. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-1}{2250}} + \left(\mathsf{neg}\left(\frac{1}{75}\right)\right), \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    12. metadata-evalN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \frac{-1}{2250} + \color{blue}{\frac{-1}{75}}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    13. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-1}{2250}, \frac{-1}{75}\right)}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    14. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    15. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    16. metadata-eval95.6

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), \color{blue}{-12}\right), x\right), 2\right)} \]
  10. Simplified95.6%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), -12\right)}, x\right), 2\right)} \]
  11. Taylor expanded in x around inf

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-1}{2250} \cdot {x}^{2}}, \frac{-2}{5}\right), -12\right), x\right), 2\right)} \]
  12. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-1}{2250}}, \frac{-2}{5}\right), -12\right), x\right), 2\right)} \]
    2. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-1}{2250}}, \frac{-2}{5}\right), -12\right), x\right), 2\right)} \]
    3. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right)} \cdot \frac{-1}{2250}, \frac{-2}{5}\right), -12\right), x\right), 2\right)} \]
    4. *-lowering-*.f6495.6

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right)} \cdot -0.00044444444444444447, -0.4\right), -12\right), x\right), 2\right)} \]
  13. Simplified95.6%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\left(x \cdot x\right) \cdot -0.00044444444444444447}, -0.4\right), -12\right), x\right), 2\right)} \]
  14. Add Preprocessing

Alternative 8: 95.5% accurate, 2.6× speedup?

\[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot -0.013333333333333334, -0.4\right), -12\right), x\right), 2\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  2.0
  (fma
   x
   (fma
    (*
     (* x (* x x))
     (fma (* x x) (* (* x x) 7.71604938271605e-6) -0.006944444444444444))
    (fma x (* x (fma x (* x -0.013333333333333334) -0.4)) -12.0)
    x)
   2.0)))
double code(double x) {
	return 2.0 / fma(x, fma(((x * (x * x)) * fma((x * x), ((x * x) * 7.71604938271605e-6), -0.006944444444444444)), fma(x, (x * fma(x, (x * -0.013333333333333334), -0.4)), -12.0), x), 2.0);
}
function code(x)
	return Float64(2.0 / fma(x, fma(Float64(Float64(x * Float64(x * x)) * fma(Float64(x * x), Float64(Float64(x * x) * 7.71604938271605e-6), -0.006944444444444444)), fma(x, Float64(x * fma(x, Float64(x * -0.013333333333333334), -0.4)), -12.0), x), 2.0))
end
code[x_] := N[(2.0 / N[(x * N[(N[(N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 7.71604938271605e-6), $MachinePrecision] + -0.006944444444444444), $MachinePrecision]), $MachinePrecision] * N[(x * N[(x * N[(x * N[(x * -0.013333333333333334), $MachinePrecision] + -0.4), $MachinePrecision]), $MachinePrecision] + -12.0), $MachinePrecision] + x), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot -0.013333333333333334, -0.4\right), -12\right), 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

    \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
  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. Simplified90.4%

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(\left(x \cdot x\right) \cdot x\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)} + x, 2\right)} \]
    2. pow3N/A

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

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

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

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left({x}^{3} \cdot \left(\left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) - \frac{1}{12} \cdot \frac{1}{12}\right), \frac{1}{x \cdot \left(x \cdot \frac{1}{360}\right) - \frac{1}{12}}, x\right)}, 2\right)} \]
  7. Applied egg-rr66.0%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \frac{1}{\mathsf{fma}\left(x, x \cdot 0.002777777777777778, -0.08333333333333333\right)}, x\right)}, 2\right)} \]
  8. Taylor expanded in x around 0

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{{x}^{2} \cdot \left(\frac{-1}{75} \cdot {x}^{2} - \frac{2}{5}\right) - 12}, x\right), 2\right)} \]
  9. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{{x}^{2} \cdot \left(\frac{-1}{75} \cdot {x}^{2} - \frac{2}{5}\right) + \left(\mathsf{neg}\left(12\right)\right)}, x\right), 2\right)} \]
    2. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{\left(x \cdot x\right)} \cdot \left(\frac{-1}{75} \cdot {x}^{2} - \frac{2}{5}\right) + \left(\mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    3. associate-*l*N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{x \cdot \left(x \cdot \left(\frac{-1}{75} \cdot {x}^{2} - \frac{2}{5}\right)\right)} + \left(\mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    4. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), x \cdot \color{blue}{\left(\left(\frac{-1}{75} \cdot {x}^{2} - \frac{2}{5}\right) \cdot x\right)} + \left(\mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    5. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{\mathsf{fma}\left(x, \left(\frac{-1}{75} \cdot {x}^{2} - \frac{2}{5}\right) \cdot x, \mathsf{neg}\left(12\right)\right)}, x\right), 2\right)} \]
    6. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x, \color{blue}{x \cdot \left(\frac{-1}{75} \cdot {x}^{2} - \frac{2}{5}\right)}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    7. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x, \color{blue}{x \cdot \left(\frac{-1}{75} \cdot {x}^{2} - \frac{2}{5}\right)}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    8. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x, x \cdot \color{blue}{\left(\frac{-1}{75} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{2}{5}\right)\right)\right)}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    9. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x, x \cdot \left(\color{blue}{{x}^{2} \cdot \frac{-1}{75}} + \left(\mathsf{neg}\left(\frac{2}{5}\right)\right)\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    10. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x, x \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \frac{-1}{75} + \left(\mathsf{neg}\left(\frac{2}{5}\right)\right)\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    11. associate-*l*N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x, x \cdot \left(\color{blue}{x \cdot \left(x \cdot \frac{-1}{75}\right)} + \left(\mathsf{neg}\left(\frac{2}{5}\right)\right)\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    12. metadata-evalN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x, x \cdot \left(x \cdot \left(x \cdot \frac{-1}{75}\right) + \color{blue}{\frac{-2}{5}}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    13. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x, x \cdot \color{blue}{\mathsf{fma}\left(x, x \cdot \frac{-1}{75}, \frac{-2}{5}\right)}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    14. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, \color{blue}{x \cdot \frac{-1}{75}}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    15. metadata-eval95.5

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot -0.013333333333333334, -0.4\right), \color{blue}{-12}\right), x\right), 2\right)} \]
  10. Simplified95.5%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \color{blue}{\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot -0.013333333333333334, -0.4\right), -12\right)}, x\right), 2\right)} \]
  11. Add Preprocessing

Alternative 9: 94.7% accurate, 3.0× speedup?

\[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot -0.006944444444444444, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), -12\right), x\right), 2\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  2.0
  (fma
   x
   (fma
    (* (* x (* x x)) -0.006944444444444444)
    (fma
     (* x x)
     (fma
      (* x x)
      (fma (* x x) -0.00044444444444444447 -0.013333333333333334)
      -0.4)
     -12.0)
    x)
   2.0)))
double code(double x) {
	return 2.0 / fma(x, fma(((x * (x * x)) * -0.006944444444444444), fma((x * x), fma((x * x), fma((x * x), -0.00044444444444444447, -0.013333333333333334), -0.4), -12.0), x), 2.0);
}
function code(x)
	return Float64(2.0 / fma(x, fma(Float64(Float64(x * Float64(x * x)) * -0.006944444444444444), fma(Float64(x * x), fma(Float64(x * x), fma(Float64(x * x), -0.00044444444444444447, -0.013333333333333334), -0.4), -12.0), x), 2.0))
end
code[x_] := N[(2.0 / N[(x * N[(N[(N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] * -0.006944444444444444), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * -0.00044444444444444447 + -0.013333333333333334), $MachinePrecision] + -0.4), $MachinePrecision] + -12.0), $MachinePrecision] + x), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot -0.006944444444444444, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), -12\right), 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

    \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
  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. Simplified90.4%

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(\left(x \cdot x\right) \cdot x\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)} + x, 2\right)} \]
    2. pow3N/A

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

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

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

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left({x}^{3} \cdot \left(\left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) - \frac{1}{12} \cdot \frac{1}{12}\right), \frac{1}{x \cdot \left(x \cdot \frac{1}{360}\right) - \frac{1}{12}}, x\right)}, 2\right)} \]
  7. Applied egg-rr66.0%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \frac{1}{\mathsf{fma}\left(x, x \cdot 0.002777777777777778, -0.08333333333333333\right)}, x\right)}, 2\right)} \]
  8. Taylor expanded in x around 0

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{{x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}\right) - 12}, x\right), 2\right)} \]
  9. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{{x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}\right) + \left(\mathsf{neg}\left(12\right)\right)}, x\right), 2\right)} \]
    2. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{\mathsf{fma}\left({x}^{2}, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}, \mathsf{neg}\left(12\right)\right)}, x\right), 2\right)} \]
    3. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(\color{blue}{x \cdot x}, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(\color{blue}{x \cdot x}, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) - \frac{2}{5}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    5. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) + \left(\mathsf{neg}\left(\frac{2}{5}\right)\right)}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    6. metadata-evalN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \left(\frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}\right) + \color{blue}{\frac{-2}{5}}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    7. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}, \frac{-2}{5}\right)}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    8. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    9. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250} \cdot {x}^{2} - \frac{1}{75}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    10. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{-1}{2250} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{75}\right)\right)}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    11. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{{x}^{2} \cdot \frac{-1}{2250}} + \left(\mathsf{neg}\left(\frac{1}{75}\right)\right), \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    12. metadata-evalN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, {x}^{2} \cdot \frac{-1}{2250} + \color{blue}{\frac{-1}{75}}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    13. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-1}{2250}, \frac{-1}{75}\right)}, \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    14. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    15. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    16. metadata-eval95.6

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), \color{blue}{-12}\right), x\right), 2\right)} \]
  10. Simplified95.6%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), -12\right)}, x\right), 2\right)} \]
  11. Taylor expanded in x around 0

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\color{blue}{\frac{-1}{144} \cdot {x}^{3}}, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), -12\right), x\right), 2\right)} \]
  12. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\color{blue}{\frac{-1}{144} \cdot {x}^{3}}, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), -12\right), x\right), 2\right)} \]
    2. cube-multN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\frac{-1}{144} \cdot \color{blue}{\left(x \cdot \left(x \cdot x\right)\right)}, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), -12\right), x\right), 2\right)} \]
    3. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\frac{-1}{144} \cdot \left(x \cdot \color{blue}{{x}^{2}}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), -12\right), x\right), 2\right)} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\frac{-1}{144} \cdot \color{blue}{\left(x \cdot {x}^{2}\right)}, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), -12\right), x\right), 2\right)} \]
    5. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\frac{-1}{144} \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \frac{-1}{2250}, \frac{-1}{75}\right), \frac{-2}{5}\right), -12\right), x\right), 2\right)} \]
    6. *-lowering-*.f6494.1

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(-0.006944444444444444 \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right), \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), -12\right), x\right), 2\right)} \]
  13. Simplified94.1%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\color{blue}{-0.006944444444444444 \cdot \left(x \cdot \left(x \cdot x\right)\right)}, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), -12\right), x\right), 2\right)} \]
  14. Final simplification94.1%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot -0.006944444444444444, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, -0.00044444444444444447, -0.013333333333333334\right), -0.4\right), -12\right), x\right), 2\right)} \]
  15. Add Preprocessing

Alternative 10: 94.6% accurate, 3.1× speedup?

\[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x \cdot x, -0.4, -12\right), x\right), 2\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  2.0
  (fma
   x
   (fma
    (*
     (* x (* x x))
     (fma (* x x) (* (* x x) 7.71604938271605e-6) -0.006944444444444444))
    (fma (* x x) -0.4 -12.0)
    x)
   2.0)))
double code(double x) {
	return 2.0 / fma(x, fma(((x * (x * x)) * fma((x * x), ((x * x) * 7.71604938271605e-6), -0.006944444444444444)), fma((x * x), -0.4, -12.0), x), 2.0);
}
function code(x)
	return Float64(2.0 / fma(x, fma(Float64(Float64(x * Float64(x * x)) * fma(Float64(x * x), Float64(Float64(x * x) * 7.71604938271605e-6), -0.006944444444444444)), fma(Float64(x * x), -0.4, -12.0), x), 2.0))
end
code[x_] := N[(2.0 / N[(x * N[(N[(N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 7.71604938271605e-6), $MachinePrecision] + -0.006944444444444444), $MachinePrecision]), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * -0.4 + -12.0), $MachinePrecision] + x), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x \cdot x, -0.4, -12\right), 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

    \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
  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. Simplified90.4%

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(\left(x \cdot x\right) \cdot x\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)} + x, 2\right)} \]
    2. pow3N/A

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

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

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

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left({x}^{3} \cdot \left(\left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) - \frac{1}{12} \cdot \frac{1}{12}\right), \frac{1}{x \cdot \left(x \cdot \frac{1}{360}\right) - \frac{1}{12}}, x\right)}, 2\right)} \]
  7. Applied egg-rr66.0%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \frac{1}{\mathsf{fma}\left(x, x \cdot 0.002777777777777778, -0.08333333333333333\right)}, x\right)}, 2\right)} \]
  8. Taylor expanded in x around 0

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{\frac{-2}{5} \cdot {x}^{2} - 12}, x\right), 2\right)} \]
  9. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{\frac{-2}{5} \cdot {x}^{2} + \left(\mathsf{neg}\left(12\right)\right)}, x\right), 2\right)} \]
    2. *-commutativeN/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{{x}^{2} \cdot \frac{-2}{5}} + \left(\mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    3. accelerator-lowering-fma.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{\mathsf{fma}\left({x}^{2}, \frac{-2}{5}, \mathsf{neg}\left(12\right)\right)}, x\right), 2\right)} \]
    4. unpow2N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-2}{5}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    5. *-lowering-*.f64N/A

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \mathsf{fma}\left(\color{blue}{x \cdot x}, \frac{-2}{5}, \mathsf{neg}\left(12\right)\right), x\right), 2\right)} \]
    6. metadata-eval94.0

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \mathsf{fma}\left(x \cdot x, -0.4, \color{blue}{-12}\right), x\right), 2\right)} \]
  10. Simplified94.0%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \color{blue}{\mathsf{fma}\left(x \cdot x, -0.4, -12\right)}, x\right), 2\right)} \]
  11. Add Preprocessing

Alternative 11: 93.3% accurate, 3.6× speedup?

\[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), -12, x\right), 2\right)} \end{array} \]
(FPCore (x)
 :precision binary64
 (/
  2.0
  (fma
   x
   (fma
    (*
     (* x (* x x))
     (fma (* x x) (* (* x x) 7.71604938271605e-6) -0.006944444444444444))
    -12.0
    x)
   2.0)))
double code(double x) {
	return 2.0 / fma(x, fma(((x * (x * x)) * fma((x * x), ((x * x) * 7.71604938271605e-6), -0.006944444444444444)), -12.0, x), 2.0);
}
function code(x)
	return Float64(2.0 / fma(x, fma(Float64(Float64(x * Float64(x * x)) * fma(Float64(x * x), Float64(Float64(x * x) * 7.71604938271605e-6), -0.006944444444444444)), -12.0, x), 2.0))
end
code[x_] := N[(2.0 / N[(x * N[(N[(N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 7.71604938271605e-6), $MachinePrecision] + -0.006944444444444444), $MachinePrecision]), $MachinePrecision] * -12.0 + x), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), -12, 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

    \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
  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. Simplified90.4%

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\left(\left(x \cdot x\right) \cdot x\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right)} + x, 2\right)} \]
    2. pow3N/A

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

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

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

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left({x}^{3} \cdot \left(\left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{360}\right)\right) - \frac{1}{12} \cdot \frac{1}{12}\right), \frac{1}{x \cdot \left(x \cdot \frac{1}{360}\right) - \frac{1}{12}}, x\right)}, 2\right)} \]
  7. Applied egg-rr66.0%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \frac{1}{\mathsf{fma}\left(x, x \cdot 0.002777777777777778, -0.08333333333333333\right)}, x\right)}, 2\right)} \]
  8. Taylor expanded in x around 0

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot \frac{1}{129600}, \frac{-1}{144}\right), \color{blue}{-12}, x\right), 2\right)} \]
  9. Step-by-step derivation
    1. Simplified93.2%

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(\left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x \cdot x, \left(x \cdot x\right) \cdot 7.71604938271605 \cdot 10^{-6}, -0.006944444444444444\right), \color{blue}{-12}, x\right), 2\right)} \]
    2. Add Preprocessing

    Alternative 12: 91.2% accurate, 4.8× speedup?

    \[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot \mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\right), x\right), 2\right)} \end{array} \]
    (FPCore (x)
     :precision binary64
     (/
      2.0
      (fma
       x
       (fma (* x x) (* x (fma x (* x 0.002777777777777778) 0.08333333333333333)) x)
       2.0)))
    double code(double x) {
    	return 2.0 / fma(x, fma((x * x), (x * fma(x, (x * 0.002777777777777778), 0.08333333333333333)), x), 2.0);
    }
    
    function code(x)
    	return Float64(2.0 / fma(x, fma(Float64(x * x), Float64(x * fma(x, Float64(x * 0.002777777777777778), 0.08333333333333333)), x), 2.0))
    end
    
    code[x_] := N[(2.0 / N[(x * N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * N[(x * 0.002777777777777778), $MachinePrecision] + 0.08333333333333333), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \frac{2}{\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)}
    \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. Simplified90.4%

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

    Alternative 13: 91.1% accurate, 4.9× speedup?

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

      \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}} \]
    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. Simplified90.4%

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, \color{blue}{\frac{1}{360} \cdot {x}^{3}}, x\right), 2\right)} \]
    7. Step-by-step derivation
      1. unpow3N/A

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

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

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

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

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

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

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot \frac{1}{360}\right), x\right), 2\right)} \]
      9. *-lowering-*.f6490.2

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot 0.002777777777777778\right), x\right), 2\right)} \]
    8. Simplified90.2%

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

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

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot \color{blue}{\left(\left(x \cdot \frac{1}{360}\right) \cdot x\right)}, x\right), 2\right)} \]
      4. *-lowering-*.f6490.2

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot \left(\color{blue}{\left(x \cdot 0.002777777777777778\right)} \cdot x\right), x\right), 2\right)} \]
    10. Applied egg-rr90.2%

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, x \cdot \color{blue}{\left(\left(x \cdot 0.002777777777777778\right) \cdot x\right)}, x\right), 2\right)} \]
    11. Final simplification90.2%

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

    Alternative 14: 90.8% accurate, 4.9× speedup?

    \[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, \left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\right), 2\right)} \end{array} \]
    (FPCore (x)
     :precision binary64
     (/
      2.0
      (fma
       x
       (* (* x (* x x)) (fma x (* x 0.002777777777777778) 0.08333333333333333))
       2.0)))
    double code(double x) {
    	return 2.0 / fma(x, ((x * (x * x)) * fma(x, (x * 0.002777777777777778), 0.08333333333333333)), 2.0);
    }
    
    function code(x)
    	return Float64(2.0 / fma(x, Float64(Float64(x * Float64(x * x)) * fma(x, Float64(x * 0.002777777777777778), 0.08333333333333333)), 2.0))
    end
    
    code[x_] := N[(2.0 / N[(x * N[(N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] * N[(x * N[(x * 0.002777777777777778), $MachinePrecision] + 0.08333333333333333), $MachinePrecision]), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \frac{2}{\mathsf{fma}\left(x, \left(x \cdot \left(x \cdot x\right)\right) \cdot \mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\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. Simplified90.4%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot \left(x \cdot x\right), \frac{1}{360}, \color{blue}{x \cdot \frac{1}{12}}\right), x\right), 2\right)} \]
      11. *-lowering-*.f6490.4

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot \left(x \cdot x\right), 0.002777777777777778, \color{blue}{x \cdot 0.08333333333333333}\right), x\right), 2\right)} \]
    7. Applied egg-rr90.4%

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

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{{x}^{5} \cdot \left(\frac{1}{360} + \frac{1}{12} \cdot \frac{1}{{x}^{2}}\right)}, 2\right)} \]
    9. Simplified90.0%

      \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(x, x \cdot 0.002777777777777778, 0.08333333333333333\right) \cdot \left(x \cdot \left(x \cdot x\right)\right)}, 2\right)} \]
    10. Final simplification90.0%

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

    Alternative 15: 90.8% accurate, 5.0× speedup?

    \[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, x \cdot \left(0.002777777777777778 \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right), 2\right)} \end{array} \]
    (FPCore (x)
     :precision binary64
     (/ 2.0 (fma x (* x (* 0.002777777777777778 (* x (* x (* x x))))) 2.0)))
    double code(double x) {
    	return 2.0 / fma(x, (x * (0.002777777777777778 * (x * (x * (x * x))))), 2.0);
    }
    
    function code(x)
    	return Float64(2.0 / fma(x, Float64(x * Float64(0.002777777777777778 * Float64(x * Float64(x * Float64(x * x))))), 2.0))
    end
    
    code[x_] := N[(2.0 / N[(x * N[(x * N[(0.002777777777777778 * N[(x * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \frac{2}{\mathsf{fma}\left(x, x \cdot \left(0.002777777777777778 \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\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. Simplified90.4%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot \left(x \cdot x\right), \frac{1}{360}, \color{blue}{x \cdot \frac{1}{12}}\right), x\right), 2\right)} \]
      11. *-lowering-*.f6490.4

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot \left(x \cdot x\right), 0.002777777777777778, \color{blue}{x \cdot 0.08333333333333333}\right), x\right), 2\right)} \]
    7. Applied egg-rr90.4%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, x \cdot \left(\frac{1}{360} \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)\right), 2\right)} \]
      26. *-lowering-*.f6490.0

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, x \cdot \left(0.002777777777777778 \cdot \left(x \cdot \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)\right), 2\right)} \]
    10. Simplified90.0%

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

    Alternative 16: 87.3% 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-*.f6487.7

        \[\leadsto \frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \color{blue}{\left(x \cdot x\right)} \cdot 0.08333333333333333, x\right), 2\right)} \]
    5. Simplified87.7%

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

    Alternative 17: 75.4% 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.f6474.7

        \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x, 2\right)}} \]
    5. Simplified74.7%

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

    Alternative 18: 50.4% 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. Simplified48.1%

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

      Reproduce

      ?
      herbie shell --seed 2024203 
      (FPCore (x)
        :name "Hyperbolic secant"
        :precision binary64
        (/ 2.0 (+ (exp x) (exp (- x)))))