Hyperbolic secant

Percentage Accurate: 100.0% → 100.0%
Time: 11.1s
Alternatives: 15
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 15 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, 0.7× speedup?

\[\begin{array}{l} \\ {\left({\cosh x}^{-0.5}\right)}^{2} \end{array} \]
(FPCore (x) :precision binary64 (pow (pow (cosh x) -0.5) 2.0))
double code(double x) {
	return pow(pow(cosh(x), -0.5), 2.0);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (cosh(x) ** (-0.5d0)) ** 2.0d0
end function
public static double code(double x) {
	return Math.pow(Math.pow(Math.cosh(x), -0.5), 2.0);
}
def code(x):
	return math.pow(math.pow(math.cosh(x), -0.5), 2.0)
function code(x)
	return (cosh(x) ^ -0.5) ^ 2.0
end
function tmp = code(x)
	tmp = (cosh(x) ^ -0.5) ^ 2.0;
end
code[x_] := N[Power[N[Power[N[Cosh[x], $MachinePrecision], -0.5], $MachinePrecision], 2.0], $MachinePrecision]
\begin{array}{l}

\\
{\left({\cosh x}^{-0.5}\right)}^{2}
\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

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

      \[\leadsto \frac{1}{\cosh x} \]
    3. inv-powN/A

      \[\leadsto {\cosh x}^{\color{blue}{-1}} \]
    4. sqr-powN/A

      \[\leadsto {\cosh x}^{\left(\frac{-1}{2}\right)} \cdot \color{blue}{{\cosh x}^{\left(\frac{-1}{2}\right)}} \]
    5. pow2N/A

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

      \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\left(\frac{-1}{2}\right)}\right), \color{blue}{2}\right) \]
    7. metadata-evalN/A

      \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\frac{-1}{2}}\right), 2\right) \]
    8. metadata-evalN/A

      \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}\right), 2\right) \]
    9. metadata-evalN/A

      \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}\right), 2\right) \]
    10. pow-lowering-pow.f64N/A

      \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\cosh x, \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right), 2\right) \]
    11. cosh-lowering-cosh.f64N/A

      \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\mathsf{cosh.f64}\left(x\right), \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right), 2\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\mathsf{cosh.f64}\left(x\right), \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right), 2\right) \]
    13. metadata-eval100.0%

      \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\mathsf{cosh.f64}\left(x\right), \frac{-1}{2}\right), 2\right) \]
  4. Applied egg-rr100.0%

    \[\leadsto \color{blue}{{\left({\cosh x}^{-0.5}\right)}^{2}} \]
  5. Add Preprocessing

Alternative 2: 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

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

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

      \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\cosh x}\right) \]
    4. cosh-lowering-cosh.f64100.0%

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{cosh.f64}\left(x\right)\right) \]
  4. Applied egg-rr100.0%

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

Alternative 3: 94.1% accurate, 2.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right)\\ \mathbf{if}\;x \leq 4 \cdot 10^{+30}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), 0.5\right), 1\right)}\\ \mathbf{elif}\;x \leq 1.15 \cdot 10^{+77}:\\ \;\;\;\;\frac{2}{\frac{\mathsf{fma}\left(t\_0, t\_0, 0\right) \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.002777777777777778, 0.08333333333333333\right), 1\right)}{\mathsf{fma}\left(x, t\_0, 0\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (fma x (fma x x 0.0) 0.0)))
   (if (<= x 4e+30)
     (/
      1.0
      (fma
       (* x x)
       (fma
        x
        (* x (fma (* x x) 0.001388888888888889 0.041666666666666664))
        0.5)
       1.0))
     (if (<= x 1.15e+77)
       (/
        2.0
        (/
         (*
          (fma t_0 t_0 0.0)
          (fma
           x
           (* x (fma (fma x x 0.0) 0.002777777777777778 0.08333333333333333))
           1.0))
         (fma x t_0 0.0)))
       (/ 24.0 (* x (* x (* x x))))))))
double code(double x) {
	double t_0 = fma(x, fma(x, x, 0.0), 0.0);
	double tmp;
	if (x <= 4e+30) {
		tmp = 1.0 / fma((x * x), fma(x, (x * fma((x * x), 0.001388888888888889, 0.041666666666666664)), 0.5), 1.0);
	} else if (x <= 1.15e+77) {
		tmp = 2.0 / ((fma(t_0, t_0, 0.0) * fma(x, (x * fma(fma(x, x, 0.0), 0.002777777777777778, 0.08333333333333333)), 1.0)) / fma(x, t_0, 0.0));
	} else {
		tmp = 24.0 / (x * (x * (x * x)));
	}
	return tmp;
}
function code(x)
	t_0 = fma(x, fma(x, x, 0.0), 0.0)
	tmp = 0.0
	if (x <= 4e+30)
		tmp = Float64(1.0 / fma(Float64(x * x), fma(x, Float64(x * fma(Float64(x * x), 0.001388888888888889, 0.041666666666666664)), 0.5), 1.0));
	elseif (x <= 1.15e+77)
		tmp = Float64(2.0 / Float64(Float64(fma(t_0, t_0, 0.0) * fma(x, Float64(x * fma(fma(x, x, 0.0), 0.002777777777777778, 0.08333333333333333)), 1.0)) / fma(x, t_0, 0.0)));
	else
		tmp = Float64(24.0 / Float64(x * Float64(x * Float64(x * x))));
	end
	return tmp
end
code[x_] := Block[{t$95$0 = N[(x * N[(x * x + 0.0), $MachinePrecision] + 0.0), $MachinePrecision]}, If[LessEqual[x, 4e+30], N[(1.0 / N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * 0.001388888888888889 + 0.041666666666666664), $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 1.15e+77], N[(2.0 / N[(N[(N[(t$95$0 * t$95$0 + 0.0), $MachinePrecision] * N[(x * N[(x * N[(N[(x * x + 0.0), $MachinePrecision] * 0.002777777777777778 + 0.08333333333333333), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision] / N[(x * t$95$0 + 0.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(24.0 / N[(x * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right)\\
\mathbf{if}\;x \leq 4 \cdot 10^{+30}:\\
\;\;\;\;\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), 0.5\right), 1\right)}\\

\mathbf{elif}\;x \leq 1.15 \cdot 10^{+77}:\\
\;\;\;\;\frac{2}{\frac{\mathsf{fma}\left(t\_0, t\_0, 0\right) \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.002777777777777778, 0.08333333333333333\right), 1\right)}{\mathsf{fma}\left(x, t\_0, 0\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 3 regimes
  2. if x < 4.0000000000000001e30

    1. Initial program 100.0%

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

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

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

        \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\cosh x}\right) \]
      4. cosh-lowering-cosh.f64100.0%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{cosh.f64}\left(x\right)\right) \]
    4. Applied egg-rr100.0%

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

      \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \left({x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \color{blue}{1}\right)\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, 1\right)\right) \]
      3. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
      5. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left({x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \color{blue}{\frac{1}{2}}\right), 1\right)\right) \]
      6. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\left(x \cdot x\right) \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \frac{1}{2}\right), 1\right)\right) \]
      7. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(x \cdot \left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \frac{1}{2}\right), 1\right)\right) \]
      8. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, \frac{1}{2}\right), 1\right)\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)}\right), \frac{1}{2}\right), 1\right)\right) \]
      10. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{720} \cdot {x}^{2} + \color{blue}{\frac{1}{24}}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      11. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left({x}^{2} \cdot \frac{1}{720} + \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      12. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{720}}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      13. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      14. *-lowering-*.f6491.5%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
    7. Simplified91.5%

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

    if 4.0000000000000001e30 < x < 1.14999999999999997e77

    1. Initial program 100.0%

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

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)}\right) \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + \color{blue}{2}\right)\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}, 2\right)\right) \]
      3. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\left({x}^{2} + 0\right), \left(\color{blue}{1} + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right), 2\right)\right) \]
      4. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\left(x \cdot x + 0\right), \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right), 2\right)\right) \]
      5. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \left(\color{blue}{1} + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right), 2\right)\right) \]
      6. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \left({x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right) + \color{blue}{1}\right), 2\right)\right) \]
      7. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \left(\left(x \cdot x\right) \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right) + 1\right), 2\right)\right) \]
      8. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \left(x \cdot \left(x \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 1\right), 2\right)\right) \]
      9. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}, 1\right), 2\right)\right) \]
      10. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \left(x \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right) + \color{blue}{0}\right), 1\right), 2\right)\right) \]
      11. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)}, 0\right), 1\right), 2\right)\right) \]
      12. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(\frac{1}{360} \cdot {x}^{2} + \color{blue}{\frac{1}{12}}\right), 0\right), 1\right), 2\right)\right) \]
      13. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left({x}^{2} \cdot \frac{1}{360} + \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
      14. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
      15. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
      16. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \frac{1}{360}\right)}, \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
      17. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(x \cdot \frac{1}{360} + \color{blue}{0}\right), \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
      18. accelerator-lowering-fma.f6450.1%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\frac{1}{360}}, 0\right), \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
    5. Simplified50.1%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(x, 0.002777777777777778, 0\right), 0.08333333333333333\right), 0\right), 1\right), 2\right)}} \]
    6. Taylor expanded in x around inf

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left({x}^{6} \cdot \left(\frac{1}{360} + \left(\frac{1}{12} \cdot \frac{1}{{x}^{2}} + \frac{1}{{x}^{4}}\right)\right)\right)}\right) \]
    7. Simplified50.1%

      \[\leadsto \frac{2}{\color{blue}{\left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, 0.002777777777777778, 0.08333333333333333\right), 1\right)}} \]
    8. Applied egg-rr100.0%

      \[\leadsto \frac{2}{\color{blue}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right), \mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right), 0\right) \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.002777777777777778, 0.08333333333333333\right), 1\right)}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right), 0\right)}}} \]

    if 1.14999999999999997e77 < x

    1. Initial program 100.0%

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

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{2}\right)\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2\right)\right) \]
      3. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right) + 2\right)\right) \]
      4. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}, 2\right)\right) \]
      5. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{0}\right), 2\right)\right) \]
      6. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}, 0\right), 2\right)\right) \]
      7. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(\frac{1}{12} \cdot {x}^{2} + \color{blue}{1}\right), 0\right), 2\right)\right) \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left({x}^{2} \cdot \frac{1}{12} + 1\right), 0\right), 2\right)\right) \]
      9. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}, 1\right), 0\right), 2\right)\right) \]
      10. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2} + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
      11. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
      12. accelerator-lowering-fma.f64100.0%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
    5. Simplified100.0%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.08333333333333333, 1\right), 0\right), 2\right)}} \]
    6. Taylor expanded in x around inf

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

        \[\leadsto \mathsf{/.f64}\left(24, \color{blue}{\left({x}^{4}\right)}\right) \]
      2. metadata-evalN/A

        \[\leadsto \mathsf{/.f64}\left(24, \left({x}^{\left(2 \cdot \color{blue}{2}\right)}\right)\right) \]
      3. pow-sqrN/A

        \[\leadsto \mathsf{/.f64}\left(24, \left({x}^{2} \cdot \color{blue}{{x}^{2}}\right)\right) \]
      4. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(24, \left(\left(x \cdot x\right) \cdot {\color{blue}{x}}^{2}\right)\right) \]
      5. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(24, \left(x \cdot \color{blue}{\left(x \cdot {x}^{2}\right)}\right)\right) \]
      6. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(24, \left(x \cdot \left(x \cdot \left(x \cdot \color{blue}{x}\right)\right)\right)\right) \]
      7. cube-multN/A

        \[\leadsto \mathsf{/.f64}\left(24, \left(x \cdot {x}^{\color{blue}{3}}\right)\right) \]
      8. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{3}\right)}\right)\right) \]
      9. cube-multN/A

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)\right) \]
      10. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \left(x \cdot {x}^{\color{blue}{2}}\right)\right)\right) \]
      11. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right)\right) \]
      12. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right)\right) \]
      13. *-lowering-*.f64100.0%

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right)\right) \]
    8. Simplified100.0%

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

Alternative 4: 93.4% accurate, 2.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 10^{+26}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), 0.5\right), 1\right)}\\ \mathbf{elif}\;x \leq 1.35 \cdot 10^{+154}:\\ \;\;\;\;\frac{2}{\frac{\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.002777777777777778, 0.08333333333333333\right), 1\right) \cdot \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right), 0\right)}{\mathsf{fma}\left(x, x, 0\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{2}{x \cdot x}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 1e+26)
   (/
    1.0
    (fma
     (* x x)
     (fma x (* x (fma (* x x) 0.001388888888888889 0.041666666666666664)) 0.5)
     1.0))
   (if (<= x 1.35e+154)
     (/
      2.0
      (/
       (*
        (fma
         x
         (* x (fma (fma x x 0.0) 0.002777777777777778 0.08333333333333333))
         1.0)
        (fma x (fma x (fma x x 0.0) 0.0) 0.0))
       (fma x x 0.0)))
     (/ 2.0 (* x x)))))
double code(double x) {
	double tmp;
	if (x <= 1e+26) {
		tmp = 1.0 / fma((x * x), fma(x, (x * fma((x * x), 0.001388888888888889, 0.041666666666666664)), 0.5), 1.0);
	} else if (x <= 1.35e+154) {
		tmp = 2.0 / ((fma(x, (x * fma(fma(x, x, 0.0), 0.002777777777777778, 0.08333333333333333)), 1.0) * fma(x, fma(x, fma(x, x, 0.0), 0.0), 0.0)) / fma(x, x, 0.0));
	} else {
		tmp = 2.0 / (x * x);
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= 1e+26)
		tmp = Float64(1.0 / fma(Float64(x * x), fma(x, Float64(x * fma(Float64(x * x), 0.001388888888888889, 0.041666666666666664)), 0.5), 1.0));
	elseif (x <= 1.35e+154)
		tmp = Float64(2.0 / Float64(Float64(fma(x, Float64(x * fma(fma(x, x, 0.0), 0.002777777777777778, 0.08333333333333333)), 1.0) * fma(x, fma(x, fma(x, x, 0.0), 0.0), 0.0)) / fma(x, x, 0.0)));
	else
		tmp = Float64(2.0 / Float64(x * x));
	end
	return tmp
end
code[x_] := If[LessEqual[x, 1e+26], N[(1.0 / N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * 0.001388888888888889 + 0.041666666666666664), $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 1.35e+154], N[(2.0 / N[(N[(N[(x * N[(x * N[(N[(x * x + 0.0), $MachinePrecision] * 0.002777777777777778 + 0.08333333333333333), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision] * N[(x * N[(x * N[(x * x + 0.0), $MachinePrecision] + 0.0), $MachinePrecision] + 0.0), $MachinePrecision]), $MachinePrecision] / N[(x * x + 0.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(2.0 / N[(x * x), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 10^{+26}:\\
\;\;\;\;\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), 0.5\right), 1\right)}\\

\mathbf{elif}\;x \leq 1.35 \cdot 10^{+154}:\\
\;\;\;\;\frac{2}{\frac{\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.002777777777777778, 0.08333333333333333\right), 1\right) \cdot \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right), 0\right)}{\mathsf{fma}\left(x, x, 0\right)}}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < 1.00000000000000005e26

    1. Initial program 100.0%

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

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

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

        \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\cosh x}\right) \]
      4. cosh-lowering-cosh.f64100.0%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{cosh.f64}\left(x\right)\right) \]
    4. Applied egg-rr100.0%

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

      \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \left({x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \color{blue}{1}\right)\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, 1\right)\right) \]
      3. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
      5. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left({x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \color{blue}{\frac{1}{2}}\right), 1\right)\right) \]
      6. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\left(x \cdot x\right) \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \frac{1}{2}\right), 1\right)\right) \]
      7. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(x \cdot \left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \frac{1}{2}\right), 1\right)\right) \]
      8. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, \frac{1}{2}\right), 1\right)\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)}\right), \frac{1}{2}\right), 1\right)\right) \]
      10. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{720} \cdot {x}^{2} + \color{blue}{\frac{1}{24}}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      11. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left({x}^{2} \cdot \frac{1}{720} + \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      12. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{720}}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      13. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      14. *-lowering-*.f6492.4%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
    7. Simplified92.4%

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

    if 1.00000000000000005e26 < x < 1.35000000000000003e154

    1. Initial program 100.0%

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

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)\right)}\right) \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + \color{blue}{2}\right)\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}, 2\right)\right) \]
      3. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\left({x}^{2} + 0\right), \left(\color{blue}{1} + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right), 2\right)\right) \]
      4. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\left(x \cdot x + 0\right), \left(1 + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right), 2\right)\right) \]
      5. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \left(\color{blue}{1} + {x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right), 2\right)\right) \]
      6. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \left({x}^{2} \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right) + \color{blue}{1}\right), 2\right)\right) \]
      7. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \left(\left(x \cdot x\right) \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right) + 1\right), 2\right)\right) \]
      8. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \left(x \cdot \left(x \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right) + 1\right), 2\right)\right) \]
      9. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)\right)}, 1\right), 2\right)\right) \]
      10. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \left(x \cdot \left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right) + \color{blue}{0}\right), 1\right), 2\right)\right) \]
      11. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\left(\frac{1}{12} + \frac{1}{360} \cdot {x}^{2}\right)}, 0\right), 1\right), 2\right)\right) \]
      12. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(\frac{1}{360} \cdot {x}^{2} + \color{blue}{\frac{1}{12}}\right), 0\right), 1\right), 2\right)\right) \]
      13. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left({x}^{2} \cdot \frac{1}{360} + \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
      14. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
      15. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(x \cdot \left(x \cdot \frac{1}{360}\right) + \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
      16. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \frac{1}{360}\right)}, \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
      17. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(x \cdot \frac{1}{360} + \color{blue}{0}\right), \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
      18. accelerator-lowering-fma.f6476.9%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\frac{1}{360}}, 0\right), \frac{1}{12}\right), 0\right), 1\right), 2\right)\right) \]
    5. Simplified76.9%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(x, 0.002777777777777778, 0\right), 0.08333333333333333\right), 0\right), 1\right), 2\right)}} \]
    6. Taylor expanded in x around inf

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left({x}^{6} \cdot \left(\frac{1}{360} + \left(\frac{1}{12} \cdot \frac{1}{{x}^{2}} + \frac{1}{{x}^{4}}\right)\right)\right)}\right) \]
    7. Simplified76.9%

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

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x + 0\right) \cdot \left(\color{blue}{\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right)} + 1\right)\right)\right) \]
      2. flip-+N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{\left(x \cdot x\right) \cdot \left(x \cdot x\right) - 0 \cdot 0}{x \cdot x - 0} \cdot \left(\color{blue}{\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right)} + 1\right)\right)\right) \]
      3. --rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{\left(x \cdot x\right) \cdot \left(x \cdot x\right) - 0 \cdot 0}{x \cdot x} \cdot \left(\left(x \cdot x\right) \cdot \color{blue}{\left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right)} + 1\right)\right)\right) \]
      4. associate-*l/N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{\left(\left(x \cdot x\right) \cdot \left(x \cdot x\right) - 0 \cdot 0\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right) + 1\right)}{\color{blue}{x \cdot x}}\right)\right) \]
      5. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{/.f64}\left(\left(\left(\left(x \cdot x\right) \cdot \left(x \cdot x\right) - 0 \cdot 0\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{360} + \frac{1}{12}\right) + 1\right)\right), \color{blue}{\left(x \cdot x\right)}\right)\right) \]
    9. Applied egg-rr88.2%

      \[\leadsto \frac{2}{\color{blue}{\frac{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right), 0\right) \cdot \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.002777777777777778, 0.08333333333333333\right), 1\right)}{\mathsf{fma}\left(x, x, 0\right)}}} \]

    if 1.35000000000000003e154 < x

    1. Initial program 100.0%

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

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2}\right)}\right) \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{2} + \color{blue}{2}\right)\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot x + 2\right)\right) \]
      3. accelerator-lowering-fma.f64100.0%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \color{blue}{x}, 2\right)\right) \]
    5. Simplified100.0%

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

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

        \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left({x}^{2}\right)}\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \color{blue}{x}\right)\right) \]
      3. *-lowering-*.f64100.0%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right) \]
    8. Simplified100.0%

      \[\leadsto \color{blue}{\frac{2}{x \cdot x}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification92.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 10^{+26}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), 0.5\right), 1\right)}\\ \mathbf{elif}\;x \leq 1.35 \cdot 10^{+154}:\\ \;\;\;\;\frac{2}{\frac{\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.002777777777777778, 0.08333333333333333\right), 1\right) \cdot \mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right), 0\right)}{\mathsf{fma}\left(x, x, 0\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{2}{x \cdot x}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 90.3% accurate, 4.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 4.5:\\ \;\;\;\;\frac{2}{\mathsf{fma}\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right), x \cdot 0.08333333333333333, \mathsf{fma}\left(x, x, 2\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right)\right)}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 4.5)
   (/
    2.0
    (fma (fma x (fma x x 0.0) 0.0) (* x 0.08333333333333333) (fma x x 2.0)))
   (/
    1.0
    (*
     (* x x)
     (* (* x x) (fma (* x x) 0.001388888888888889 0.041666666666666664))))))
double code(double x) {
	double tmp;
	if (x <= 4.5) {
		tmp = 2.0 / fma(fma(x, fma(x, x, 0.0), 0.0), (x * 0.08333333333333333), fma(x, x, 2.0));
	} else {
		tmp = 1.0 / ((x * x) * ((x * x) * fma((x * x), 0.001388888888888889, 0.041666666666666664)));
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= 4.5)
		tmp = Float64(2.0 / fma(fma(x, fma(x, x, 0.0), 0.0), Float64(x * 0.08333333333333333), fma(x, x, 2.0)));
	else
		tmp = Float64(1.0 / Float64(Float64(x * x) * Float64(Float64(x * x) * fma(Float64(x * x), 0.001388888888888889, 0.041666666666666664))));
	end
	return tmp
end
code[x_] := If[LessEqual[x, 4.5], N[(2.0 / N[(N[(x * N[(x * x + 0.0), $MachinePrecision] + 0.0), $MachinePrecision] * N[(x * 0.08333333333333333), $MachinePrecision] + N[(x * x + 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 0.001388888888888889 + 0.041666666666666664), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 4.5:\\
\;\;\;\;\frac{2}{\mathsf{fma}\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right), x \cdot 0.08333333333333333, \mathsf{fma}\left(x, x, 2\right)\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right)\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 4.5

    1. Initial program 100.0%

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

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{2}\right)\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2\right)\right) \]
      3. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right) + 2\right)\right) \]
      4. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}, 2\right)\right) \]
      5. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{0}\right), 2\right)\right) \]
      6. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}, 0\right), 2\right)\right) \]
      7. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(\frac{1}{12} \cdot {x}^{2} + \color{blue}{1}\right), 0\right), 2\right)\right) \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left({x}^{2} \cdot \frac{1}{12} + 1\right), 0\right), 2\right)\right) \]
      9. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}, 1\right), 0\right), 2\right)\right) \]
      10. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2} + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
      11. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
      12. accelerator-lowering-fma.f6493.1%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
    5. Simplified93.1%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.08333333333333333, 1\right), 0\right), 2\right)}} \]
    6. Step-by-step derivation
      1. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(x \cdot \left(\left(x \cdot x + 0\right) \cdot \frac{1}{12} + 1\right)\right) + 2\right)\right) \]
      2. distribute-rgt-inN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(\left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right) \cdot x + 1 \cdot x\right) + 2\right)\right) \]
      3. *-lft-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(\left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right) \cdot x + x\right) + 2\right)\right) \]
      4. distribute-lft-inN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot \left(\left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right) \cdot x\right) + x \cdot x\right) + 2\right)\right) \]
      5. associate-+l+N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(\left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right) \cdot x\right) + \color{blue}{\left(x \cdot x + 2\right)}\right)\right) \]
      6. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(x \cdot \left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right)\right) + \left(x \cdot \color{blue}{x} + 2\right)\right)\right) \]
      7. associate-*r*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right) + \left(\color{blue}{x \cdot x} + 2\right)\right)\right) \]
      8. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) + \left(x \cdot x + 2\right)\right)\right) \]
      9. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{12}\right)\right) + \left(x \cdot \color{blue}{x} + 2\right)\right)\right) \]
      10. associate-*r*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(\left(x \cdot x\right) \cdot x\right) \cdot \left(x \cdot \frac{1}{12}\right) + \left(\color{blue}{x \cdot x} + 2\right)\right)\right) \]
      11. pow3N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{3} \cdot \left(x \cdot \frac{1}{12}\right) + \left(\color{blue}{x} \cdot x + 2\right)\right)\right) \]
      12. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\left({x}^{3}\right), \color{blue}{\left(x \cdot \frac{1}{12}\right)}, \left(x \cdot x + 2\right)\right)\right) \]
    7. Applied egg-rr93.1%

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

    if 4.5 < x

    1. Initial program 100.0%

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

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

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

        \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\cosh x}\right) \]
      4. cosh-lowering-cosh.f64100.0%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{cosh.f64}\left(x\right)\right) \]
    4. Applied egg-rr100.0%

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

      \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \left({x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \color{blue}{1}\right)\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, 1\right)\right) \]
      3. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
      5. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left({x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \color{blue}{\frac{1}{2}}\right), 1\right)\right) \]
      6. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\left(x \cdot x\right) \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \frac{1}{2}\right), 1\right)\right) \]
      7. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(x \cdot \left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \frac{1}{2}\right), 1\right)\right) \]
      8. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, \frac{1}{2}\right), 1\right)\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)}\right), \frac{1}{2}\right), 1\right)\right) \]
      10. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{720} \cdot {x}^{2} + \color{blue}{\frac{1}{24}}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      11. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left({x}^{2} \cdot \frac{1}{720} + \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      12. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{720}}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      13. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      14. *-lowering-*.f6482.3%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
    7. Simplified82.3%

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), 0.5\right), 1\right)}} \]
    8. Taylor expanded in x around inf

      \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left({x}^{6} \cdot \left(\frac{1}{720} + \frac{1}{24} \cdot \frac{1}{{x}^{2}}\right)\right)}\right) \]
    9. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \left({x}^{6} \cdot \left(\frac{1}{24} \cdot \frac{1}{{x}^{2}} + \color{blue}{\frac{1}{720}}\right)\right)\right) \]
      2. distribute-rgt-inN/A

        \[\leadsto \mathsf{/.f64}\left(1, \left(\left(\frac{1}{24} \cdot \frac{1}{{x}^{2}}\right) \cdot {x}^{6} + \color{blue}{\frac{1}{720} \cdot {x}^{6}}\right)\right) \]
    10. Simplified82.3%

      \[\leadsto \frac{1}{\color{blue}{\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right)\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 6: 90.3% accurate, 4.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 6.2:\\ \;\;\;\;\frac{2}{\mathsf{fma}\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right), x \cdot 0.08333333333333333, \mathsf{fma}\left(x, x, 2\right)\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{720}{x \cdot \left(x \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 6.2)
   (/
    2.0
    (fma (fma x (fma x x 0.0) 0.0) (* x 0.08333333333333333) (fma x x 2.0)))
   (/ 720.0 (* x (* x (* x (* x (* x x))))))))
double code(double x) {
	double tmp;
	if (x <= 6.2) {
		tmp = 2.0 / fma(fma(x, fma(x, x, 0.0), 0.0), (x * 0.08333333333333333), fma(x, x, 2.0));
	} else {
		tmp = 720.0 / (x * (x * (x * (x * (x * x)))));
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= 6.2)
		tmp = Float64(2.0 / fma(fma(x, fma(x, x, 0.0), 0.0), Float64(x * 0.08333333333333333), fma(x, x, 2.0)));
	else
		tmp = Float64(720.0 / Float64(x * Float64(x * Float64(x * Float64(x * Float64(x * x))))));
	end
	return tmp
end
code[x_] := If[LessEqual[x, 6.2], N[(2.0 / N[(N[(x * N[(x * x + 0.0), $MachinePrecision] + 0.0), $MachinePrecision] * N[(x * 0.08333333333333333), $MachinePrecision] + N[(x * x + 2.0), $MachinePrecision]), $MachinePrecision]), $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}\;x \leq 6.2:\\
\;\;\;\;\frac{2}{\mathsf{fma}\left(\mathsf{fma}\left(x, \mathsf{fma}\left(x, x, 0\right), 0\right), x \cdot 0.08333333333333333, \mathsf{fma}\left(x, x, 2\right)\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 x < 6.20000000000000018

    1. Initial program 100.0%

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

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{2}\right)\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2\right)\right) \]
      3. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right) + 2\right)\right) \]
      4. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}, 2\right)\right) \]
      5. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{0}\right), 2\right)\right) \]
      6. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}, 0\right), 2\right)\right) \]
      7. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(\frac{1}{12} \cdot {x}^{2} + \color{blue}{1}\right), 0\right), 2\right)\right) \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left({x}^{2} \cdot \frac{1}{12} + 1\right), 0\right), 2\right)\right) \]
      9. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}, 1\right), 0\right), 2\right)\right) \]
      10. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2} + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
      11. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
      12. accelerator-lowering-fma.f6493.1%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
    5. Simplified93.1%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.08333333333333333, 1\right), 0\right), 2\right)}} \]
    6. Step-by-step derivation
      1. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(x \cdot \left(\left(x \cdot x + 0\right) \cdot \frac{1}{12} + 1\right)\right) + 2\right)\right) \]
      2. distribute-rgt-inN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(\left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right) \cdot x + 1 \cdot x\right) + 2\right)\right) \]
      3. *-lft-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(\left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right) \cdot x + x\right) + 2\right)\right) \]
      4. distribute-lft-inN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot \left(\left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right) \cdot x\right) + x \cdot x\right) + 2\right)\right) \]
      5. associate-+l+N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(\left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right) \cdot x\right) + \color{blue}{\left(x \cdot x + 2\right)}\right)\right) \]
      6. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(x \cdot \left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right)\right) + \left(x \cdot \color{blue}{x} + 2\right)\right)\right) \]
      7. associate-*r*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right) + \left(\color{blue}{x \cdot x} + 2\right)\right)\right) \]
      8. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) + \left(x \cdot x + 2\right)\right)\right) \]
      9. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \frac{1}{12}\right)\right) + \left(x \cdot \color{blue}{x} + 2\right)\right)\right) \]
      10. associate-*r*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(\left(x \cdot x\right) \cdot x\right) \cdot \left(x \cdot \frac{1}{12}\right) + \left(\color{blue}{x \cdot x} + 2\right)\right)\right) \]
      11. pow3N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{3} \cdot \left(x \cdot \frac{1}{12}\right) + \left(\color{blue}{x} \cdot x + 2\right)\right)\right) \]
      12. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(\left({x}^{3}\right), \color{blue}{\left(x \cdot \frac{1}{12}\right)}, \left(x \cdot x + 2\right)\right)\right) \]
    7. Applied egg-rr93.1%

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

    if 6.20000000000000018 < x

    1. Initial program 100.0%

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

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

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

        \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\cosh x}\right) \]
      4. cosh-lowering-cosh.f64100.0%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{cosh.f64}\left(x\right)\right) \]
    4. Applied egg-rr100.0%

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

      \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \left({x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \color{blue}{1}\right)\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, 1\right)\right) \]
      3. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
      5. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left({x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \color{blue}{\frac{1}{2}}\right), 1\right)\right) \]
      6. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\left(x \cdot x\right) \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \frac{1}{2}\right), 1\right)\right) \]
      7. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(x \cdot \left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \frac{1}{2}\right), 1\right)\right) \]
      8. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, \frac{1}{2}\right), 1\right)\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)}\right), \frac{1}{2}\right), 1\right)\right) \]
      10. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{720} \cdot {x}^{2} + \color{blue}{\frac{1}{24}}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      11. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left({x}^{2} \cdot \frac{1}{720} + \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      12. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{720}}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      13. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      14. *-lowering-*.f6482.3%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
    7. Simplified82.3%

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), 0.5\right), 1\right)}} \]
    8. Taylor expanded in x around inf

      \[\leadsto \color{blue}{\frac{720}{{x}^{6}}} \]
    9. Simplified82.3%

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

Alternative 7: 92.5% accurate, 4.8× speedup?

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

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

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

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

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

      \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\cosh x}\right) \]
    4. cosh-lowering-cosh.f64100.0%

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{cosh.f64}\left(x\right)\right) \]
  4. Applied egg-rr100.0%

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

    \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)}\right) \]
  6. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(1, \left({x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \color{blue}{1}\right)\right) \]
    2. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, 1\right)\right) \]
    3. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left({x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \color{blue}{\frac{1}{2}}\right), 1\right)\right) \]
    6. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\left(x \cdot x\right) \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \frac{1}{2}\right), 1\right)\right) \]
    7. associate-*l*N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(x \cdot \left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \frac{1}{2}\right), 1\right)\right) \]
    8. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, \frac{1}{2}\right), 1\right)\right) \]
    9. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)}\right), \frac{1}{2}\right), 1\right)\right) \]
    10. +-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{720} \cdot {x}^{2} + \color{blue}{\frac{1}{24}}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
    11. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left({x}^{2} \cdot \frac{1}{720} + \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
    12. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{720}}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
    13. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
    14. *-lowering-*.f6491.4%

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
  7. Simplified91.4%

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

Alternative 8: 90.3% accurate, 5.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 6.2:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, 0.041666666666666664, 0.5\right), 1\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{720}{x \cdot \left(x \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 6.2)
   (/ 1.0 (fma (* x x) (fma (* x x) 0.041666666666666664 0.5) 1.0))
   (/ 720.0 (* x (* x (* x (* x (* x x))))))))
double code(double x) {
	double tmp;
	if (x <= 6.2) {
		tmp = 1.0 / fma((x * x), fma((x * x), 0.041666666666666664, 0.5), 1.0);
	} else {
		tmp = 720.0 / (x * (x * (x * (x * (x * x)))));
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= 6.2)
		tmp = Float64(1.0 / fma(Float64(x * x), fma(Float64(x * x), 0.041666666666666664, 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[x, 6.2], N[(1.0 / N[(N[(x * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 0.041666666666666664 + 0.5), $MachinePrecision] + 1.0), $MachinePrecision]), $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}\;x \leq 6.2:\\
\;\;\;\;\frac{1}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, 0.041666666666666664, 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 x < 6.20000000000000018

    1. Initial program 100.0%

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

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

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

        \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\cosh x}\right) \]
      4. cosh-lowering-cosh.f64100.0%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{cosh.f64}\left(x\right)\right) \]
    4. Applied egg-rr100.0%

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

      \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right)\right)}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \left({x}^{2} \cdot \left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right) + \color{blue}{1}\right)\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right)}, 1\right)\right) \]
      3. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{2}} + \frac{1}{24} \cdot {x}^{2}\right), 1\right)\right) \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{2}} + \frac{1}{24} \cdot {x}^{2}\right), 1\right)\right) \]
      5. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{24} \cdot {x}^{2} + \color{blue}{\frac{1}{2}}\right), 1\right)\right) \]
      6. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left({x}^{2} \cdot \frac{1}{24} + \frac{1}{2}\right), 1\right)\right) \]
      7. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{24}}, \frac{1}{2}\right), 1\right)\right) \]
      8. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(\left(x \cdot x\right), \frac{1}{24}, \frac{1}{2}\right), 1\right)\right) \]
      9. *-lowering-*.f6493.1%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{24}, \frac{1}{2}\right), 1\right)\right) \]
    7. Simplified93.1%

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

    if 6.20000000000000018 < x

    1. Initial program 100.0%

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

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

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

        \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\cosh x}\right) \]
      4. cosh-lowering-cosh.f64100.0%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{cosh.f64}\left(x\right)\right) \]
    4. Applied egg-rr100.0%

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

      \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)}\right) \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \left({x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \color{blue}{1}\right)\right) \]
      2. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, 1\right)\right) \]
      3. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
      4. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right), 1\right)\right) \]
      5. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left({x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \color{blue}{\frac{1}{2}}\right), 1\right)\right) \]
      6. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\left(x \cdot x\right) \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right) + \frac{1}{2}\right), 1\right)\right) \]
      7. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(x \cdot \left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) + \frac{1}{2}\right), 1\right)\right) \]
      8. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}, \frac{1}{2}\right), 1\right)\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)}\right), \frac{1}{2}\right), 1\right)\right) \]
      10. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{1}{720} \cdot {x}^{2} + \color{blue}{\frac{1}{24}}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      11. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left({x}^{2} \cdot \frac{1}{720} + \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      12. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{720}}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      13. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
      14. *-lowering-*.f6482.3%

        \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{720}, \frac{1}{24}\right)\right), \frac{1}{2}\right), 1\right)\right) \]
    7. Simplified82.3%

      \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), 0.5\right), 1\right)}} \]
    8. Taylor expanded in x around inf

      \[\leadsto \color{blue}{\frac{720}{{x}^{6}}} \]
    9. Simplified82.3%

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

Alternative 9: 88.4% accurate, 6.4× speedup?

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

\\
\frac{2}{\mathsf{fma}\left(x, \mathsf{fma}\left(x \cdot \left(x \cdot 0.08333333333333333\right), x, 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

    \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
  4. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{2}\right)\right) \]
    2. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2\right)\right) \]
    3. associate-*l*N/A

      \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right) + 2\right)\right) \]
    4. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}, 2\right)\right) \]
    5. +-rgt-identityN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{0}\right), 2\right)\right) \]
    6. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}, 0\right), 2\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(\frac{1}{12} \cdot {x}^{2} + \color{blue}{1}\right), 0\right), 2\right)\right) \]
    8. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left({x}^{2} \cdot \frac{1}{12} + 1\right), 0\right), 2\right)\right) \]
    9. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}, 1\right), 0\right), 2\right)\right) \]
    10. +-rgt-identityN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2} + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
    11. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
    12. accelerator-lowering-fma.f6488.4%

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
  5. Simplified88.4%

    \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.08333333333333333, 1\right), 0\right), 2\right)}} \]
  6. Step-by-step derivation
    1. +-rgt-identityN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(x \cdot \color{blue}{\left(\left(x \cdot x + 0\right) \cdot \frac{1}{12} + 1\right)}\right), 2\right)\right) \]
    2. distribute-lft-inN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(x \cdot \left(\left(x \cdot x + 0\right) \cdot \frac{1}{12}\right) + \color{blue}{x \cdot 1}\right), 2\right)\right) \]
    3. +-rgt-identityN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(x \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) + x \cdot 1\right), 2\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(x \cdot \left(\frac{1}{12} \cdot \left(x \cdot x\right)\right) + x \cdot 1\right), 2\right)\right) \]
    5. associate-*r*N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(\left(x \cdot \frac{1}{12}\right) \cdot \left(x \cdot x\right) + \color{blue}{x} \cdot 1\right), 2\right)\right) \]
    6. *-rgt-identityN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(\left(x \cdot \frac{1}{12}\right) \cdot \left(x \cdot x\right) + x\right), 2\right)\right) \]
    7. associate-*r*N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(\left(\left(x \cdot \frac{1}{12}\right) \cdot x\right) \cdot x + x\right), 2\right)\right) \]
    8. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left(\left(x \cdot \frac{1}{12}\right) \cdot x\right), \color{blue}{x}, x\right), 2\right)\right) \]
    9. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(\left(x \cdot \frac{1}{12}\right), x\right), x, x\right), 2\right)\right) \]
    10. *-lowering-*.f6488.4%

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(\mathsf{*.f64}\left(x, \frac{1}{12}\right), x\right), x, x\right), 2\right)\right) \]
  7. Applied egg-rr88.4%

    \[\leadsto \frac{2}{\mathsf{fma}\left(x, \color{blue}{\mathsf{fma}\left(\left(x \cdot 0.08333333333333333\right) \cdot x, x, x\right)}, 2\right)} \]
  8. Final simplification88.4%

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

Alternative 10: 69.1% accurate, 6.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.85:\\ \;\;\;\;\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot 0.20833333333333334, -0.5\right), 1\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 1.85)
   (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 (x <= 1.85) {
		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 (x <= 1.85)
		tmp = fma(x, Float64(x * fma(x, Float64(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[x, 1.85], N[(x * N[(x * N[(x * N[(x * 0.20833333333333334), $MachinePrecision] + -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}\;x \leq 1.85:\\
\;\;\;\;\mathsf{fma}\left(x, x \cdot \mathsf{fma}\left(x, x \cdot 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 x < 1.8500000000000001

    1. Initial program 100.0%

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

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

        \[\leadsto \frac{1}{\cosh x} \]
      3. inv-powN/A

        \[\leadsto {\cosh x}^{\color{blue}{-1}} \]
      4. sqr-powN/A

        \[\leadsto {\cosh x}^{\left(\frac{-1}{2}\right)} \cdot \color{blue}{{\cosh x}^{\left(\frac{-1}{2}\right)}} \]
      5. pow2N/A

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

        \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\left(\frac{-1}{2}\right)}\right), \color{blue}{2}\right) \]
      7. metadata-evalN/A

        \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\frac{-1}{2}}\right), 2\right) \]
      8. metadata-evalN/A

        \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}\right), 2\right) \]
      9. metadata-evalN/A

        \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}\right), 2\right) \]
      10. pow-lowering-pow.f64N/A

        \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\cosh x, \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right), 2\right) \]
      11. cosh-lowering-cosh.f64N/A

        \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\mathsf{cosh.f64}\left(x\right), \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right), 2\right) \]
      12. metadata-evalN/A

        \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\mathsf{cosh.f64}\left(x\right), \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right), 2\right) \]
      13. metadata-eval100.0%

        \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\mathsf{cosh.f64}\left(x\right), \frac{-1}{2}\right), 2\right) \]
    4. Applied egg-rr100.0%

      \[\leadsto \color{blue}{{\left({\cosh x}^{-0.5}\right)}^{2}} \]
    5. Taylor expanded in x around 0

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

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

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

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

        \[\leadsto \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right)\right)}, 1\right) \]
      5. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right)}\right), 1\right) \]
      6. sub-negN/A

        \[\leadsto \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{5}{24} \cdot {x}^{2} + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}\right)\right), 1\right) \]
      7. unpow2N/A

        \[\leadsto \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{5}{24} \cdot \left(x \cdot x\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)\right), 1\right) \]
      8. associate-*r*N/A

        \[\leadsto \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left(\left(\frac{5}{24} \cdot x\right) \cdot x + \left(\mathsf{neg}\left(\color{blue}{\frac{1}{2}}\right)\right)\right)\right), 1\right) \]
      9. *-commutativeN/A

        \[\leadsto \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left(x \cdot \left(\frac{5}{24} \cdot x\right) + \left(\mathsf{neg}\left(\color{blue}{\frac{1}{2}}\right)\right)\right)\right), 1\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left(x \cdot \left(\frac{5}{24} \cdot x\right) + \frac{-1}{2}\right)\right), 1\right) \]
      11. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\left(\frac{5}{24} \cdot x\right)}, \frac{-1}{2}\right)\right), 1\right) \]
      12. *-commutativeN/A

        \[\leadsto \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(x, \left(x \cdot \color{blue}{\frac{5}{24}}\right), \frac{-1}{2}\right)\right), 1\right) \]
      13. *-lowering-*.f6466.0%

        \[\leadsto \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\frac{5}{24}}\right), \frac{-1}{2}\right)\right), 1\right) \]
    7. Simplified66.0%

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

    if 1.8500000000000001 < x

    1. Initial program 100.0%

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

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{2}\right)\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2\right)\right) \]
      3. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right) + 2\right)\right) \]
      4. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}, 2\right)\right) \]
      5. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{0}\right), 2\right)\right) \]
      6. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}, 0\right), 2\right)\right) \]
      7. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(\frac{1}{12} \cdot {x}^{2} + \color{blue}{1}\right), 0\right), 2\right)\right) \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left({x}^{2} \cdot \frac{1}{12} + 1\right), 0\right), 2\right)\right) \]
      9. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}, 1\right), 0\right), 2\right)\right) \]
      10. +-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2} + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
      11. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
      12. accelerator-lowering-fma.f6475.4%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
    5. Simplified75.4%

      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.08333333333333333, 1\right), 0\right), 2\right)}} \]
    6. Taylor expanded in x around inf

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

        \[\leadsto \mathsf{/.f64}\left(24, \color{blue}{\left({x}^{4}\right)}\right) \]
      2. metadata-evalN/A

        \[\leadsto \mathsf{/.f64}\left(24, \left({x}^{\left(2 \cdot \color{blue}{2}\right)}\right)\right) \]
      3. pow-sqrN/A

        \[\leadsto \mathsf{/.f64}\left(24, \left({x}^{2} \cdot \color{blue}{{x}^{2}}\right)\right) \]
      4. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(24, \left(\left(x \cdot x\right) \cdot {\color{blue}{x}}^{2}\right)\right) \]
      5. associate-*l*N/A

        \[\leadsto \mathsf{/.f64}\left(24, \left(x \cdot \color{blue}{\left(x \cdot {x}^{2}\right)}\right)\right) \]
      6. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(24, \left(x \cdot \left(x \cdot \left(x \cdot \color{blue}{x}\right)\right)\right)\right) \]
      7. cube-multN/A

        \[\leadsto \mathsf{/.f64}\left(24, \left(x \cdot {x}^{\color{blue}{3}}\right)\right) \]
      8. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{3}\right)}\right)\right) \]
      9. cube-multN/A

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)\right) \]
      10. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \left(x \cdot {x}^{\color{blue}{2}}\right)\right)\right) \]
      11. *-lowering-*.f64N/A

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right)\right) \]
      12. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right)\right) \]
      13. *-lowering-*.f6475.4%

        \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right)\right) \]
    8. Simplified75.4%

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

Alternative 11: 88.0% accurate, 6.6× speedup?

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

\\
\frac{2}{\mathsf{fma}\left(x, x \cdot \left(\left(x \cdot x\right) \cdot 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

    \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
  4. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{2}\right)\right) \]
    2. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(2, \left(\left(x \cdot x\right) \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + 2\right)\right) \]
    3. associate-*l*N/A

      \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right) + 2\right)\right) \]
    4. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \color{blue}{\left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}, 2\right)\right) \]
    5. +-rgt-identityN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(x \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right) + \color{blue}{0}\right), 2\right)\right) \]
    6. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}, 0\right), 2\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left(\frac{1}{12} \cdot {x}^{2} + \color{blue}{1}\right), 0\right), 2\right)\right) \]
    8. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \left({x}^{2} \cdot \frac{1}{12} + 1\right), 0\right), 2\right)\right) \]
    9. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}, 1\right), 0\right), 2\right)\right) \]
    10. +-rgt-identityN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left({x}^{2} + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
    11. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\left(x \cdot x + 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
    12. accelerator-lowering-fma.f6488.4%

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(x, \mathsf{fma.f64}\left(\mathsf{fma.f64}\left(x, x, 0\right), \frac{1}{12}, 1\right), 0\right), 2\right)\right) \]
  5. Simplified88.4%

    \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, \mathsf{fma}\left(x, \mathsf{fma}\left(\mathsf{fma}\left(x, x, 0\right), 0.08333333333333333, 1\right), 0\right), 2\right)}} \]
  6. Taylor expanded in x around inf

    \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \color{blue}{\left(\frac{1}{12} \cdot {x}^{3}\right)}, 2\right)\right) \]
  7. Step-by-step derivation
    1. unpow3N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(\frac{1}{12} \cdot \left(\left(x \cdot x\right) \cdot \color{blue}{x}\right)\right), 2\right)\right) \]
    2. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(\frac{1}{12} \cdot \left({x}^{2} \cdot x\right)\right), 2\right)\right) \]
    3. associate-*r*N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(\left(\frac{1}{12} \cdot {x}^{2}\right) \cdot \color{blue}{x}\right), 2\right)\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \left(x \cdot \color{blue}{\left(\frac{1}{12} \cdot {x}^{2}\right)}\right), 2\right)\right) \]
    5. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{12} \cdot {x}^{2}\right)}\right), 2\right)\right) \]
    6. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \left({x}^{2} \cdot \color{blue}{\frac{1}{12}}\right)\right), 2\right)\right) \]
    7. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}\right)\right), 2\right)\right) \]
    8. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{12}\right)\right), 2\right)\right) \]
    9. *-lowering-*.f6488.3%

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right), 2\right)\right) \]
  8. Simplified88.3%

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

Alternative 12: 88.0% accurate, 6.6× speedup?

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

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

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

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

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

      \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\cosh x}\right) \]
    4. cosh-lowering-cosh.f64100.0%

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{cosh.f64}\left(x\right)\right) \]
  4. Applied egg-rr100.0%

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

    \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right)\right)}\right) \]
  6. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(1, \left({x}^{2} \cdot \left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right) + \color{blue}{1}\right)\right) \]
    2. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right)}, 1\right)\right) \]
    3. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{2}} + \frac{1}{24} \cdot {x}^{2}\right), 1\right)\right) \]
    4. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{2}} + \frac{1}{24} \cdot {x}^{2}\right), 1\right)\right) \]
    5. +-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{24} \cdot {x}^{2} + \color{blue}{\frac{1}{2}}\right), 1\right)\right) \]
    6. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left({x}^{2} \cdot \frac{1}{24} + \frac{1}{2}\right), 1\right)\right) \]
    7. accelerator-lowering-fma.f64N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{24}}, \frac{1}{2}\right), 1\right)\right) \]
    8. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(\left(x \cdot x\right), \frac{1}{24}, \frac{1}{2}\right), 1\right)\right) \]
    9. *-lowering-*.f6488.0%

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{24}, \frac{1}{2}\right), 1\right)\right) \]
  7. Simplified88.0%

    \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(x \cdot x, \mathsf{fma}\left(x \cdot x, 0.041666666666666664, 0.5\right), 1\right)}} \]
  8. Taylor expanded in x around inf

    \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \color{blue}{\left(\frac{1}{24} \cdot {x}^{2}\right)}, 1\right)\right) \]
  9. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \left({x}^{2} \cdot \color{blue}{\frac{1}{24}}\right), 1\right)\right) \]
    2. *-lowering-*.f64N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{24}}\right), 1\right)\right) \]
    3. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{24}\right), 1\right)\right) \]
    4. *-lowering-*.f6488.0%

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{fma.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{24}\right), 1\right)\right) \]
  10. Simplified88.0%

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

Alternative 13: 63.1% accurate, 9.4× speedup?

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

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

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


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

    1. Initial program 100.0%

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

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

        \[\leadsto \frac{1}{\cosh x} \]
      3. inv-powN/A

        \[\leadsto {\cosh x}^{\color{blue}{-1}} \]
      4. sqr-powN/A

        \[\leadsto {\cosh x}^{\left(\frac{-1}{2}\right)} \cdot \color{blue}{{\cosh x}^{\left(\frac{-1}{2}\right)}} \]
      5. pow2N/A

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

        \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\left(\frac{-1}{2}\right)}\right), \color{blue}{2}\right) \]
      7. metadata-evalN/A

        \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\frac{-1}{2}}\right), 2\right) \]
      8. metadata-evalN/A

        \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}\right), 2\right) \]
      9. metadata-evalN/A

        \[\leadsto \mathsf{pow.f64}\left(\left({\cosh x}^{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}\right), 2\right) \]
      10. pow-lowering-pow.f64N/A

        \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\cosh x, \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right), 2\right) \]
      11. cosh-lowering-cosh.f64N/A

        \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\mathsf{cosh.f64}\left(x\right), \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right), 2\right) \]
      12. metadata-evalN/A

        \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\mathsf{cosh.f64}\left(x\right), \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right), 2\right) \]
      13. metadata-eval100.0%

        \[\leadsto \mathsf{pow.f64}\left(\mathsf{pow.f64}\left(\mathsf{cosh.f64}\left(x\right), \frac{-1}{2}\right), 2\right) \]
    4. Applied egg-rr100.0%

      \[\leadsto \color{blue}{{\left({\cosh x}^{-0.5}\right)}^{2}} \]
    5. Taylor expanded in x around 0

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

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

        \[\leadsto \mathsf{fma.f64}\left(\frac{-1}{2}, \color{blue}{\left({x}^{2}\right)}, 1\right) \]
      3. unpow2N/A

        \[\leadsto \mathsf{fma.f64}\left(\frac{-1}{2}, \left(x \cdot \color{blue}{x}\right), 1\right) \]
      4. *-lowering-*.f6466.1%

        \[\leadsto \mathsf{fma.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(x, \color{blue}{x}\right), 1\right) \]
    7. Simplified66.1%

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

    if 1.25 < x

    1. Initial program 100.0%

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

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2}\right)}\right) \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{2} + \color{blue}{2}\right)\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot x + 2\right)\right) \]
      3. accelerator-lowering-fma.f6449.3%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \color{blue}{x}, 2\right)\right) \]
    5. Simplified49.3%

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

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

        \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left({x}^{2}\right)}\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \color{blue}{x}\right)\right) \]
      3. *-lowering-*.f6449.3%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right) \]
    8. Simplified49.3%

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

Alternative 14: 76.5% 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

    \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2}\right)}\right) \]
  4. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \mathsf{/.f64}\left(2, \left({x}^{2} + \color{blue}{2}\right)\right) \]
    2. unpow2N/A

      \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot x + 2\right)\right) \]
    3. accelerator-lowering-fma.f6473.9%

      \[\leadsto \mathsf{/.f64}\left(2, \mathsf{fma.f64}\left(x, \color{blue}{x}, 2\right)\right) \]
  5. Simplified73.9%

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

Alternative 15: 50.9% accurate, 217.0× speedup?

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

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

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

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

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

    Reproduce

    ?
    herbie shell --seed 2024193 
    (FPCore (x)
      :name "Hyperbolic secant"
      :precision binary64
      (/ 2.0 (+ (exp x) (exp (- x)))))