Hyperbolic arcsine

Percentage Accurate: 18.3% → 99.6%
Time: 8.2s
Alternatives: 9
Speedup: 7.2×

Specification

?
\[\begin{array}{l} \\ \log \left(x + \sqrt{x \cdot x + 1}\right) \end{array} \]
(FPCore (x) :precision binary64 (log (+ x (sqrt (+ (* x x) 1.0)))))
double code(double x) {
	return log((x + sqrt(((x * x) + 1.0))));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = log((x + sqrt(((x * x) + 1.0d0))))
end function
public static double code(double x) {
	return Math.log((x + Math.sqrt(((x * x) + 1.0))));
}
def code(x):
	return math.log((x + math.sqrt(((x * x) + 1.0))))
function code(x)
	return log(Float64(x + sqrt(Float64(Float64(x * x) + 1.0))))
end
function tmp = code(x)
	tmp = log((x + sqrt(((x * x) + 1.0))));
end
code[x_] := N[Log[N[(x + N[Sqrt[N[(N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\log \left(x + \sqrt{x \cdot x + 1}\right)
\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 9 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: 18.3% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \log \left(x + \sqrt{x \cdot x + 1}\right) \end{array} \]
(FPCore (x) :precision binary64 (log (+ x (sqrt (+ (* x x) 1.0)))))
double code(double x) {
	return log((x + sqrt(((x * x) + 1.0))));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = log((x + sqrt(((x * x) + 1.0d0))))
end function
public static double code(double x) {
	return Math.log((x + Math.sqrt(((x * x) + 1.0))));
}
def code(x):
	return math.log((x + math.sqrt(((x * x) + 1.0))))
function code(x)
	return log(Float64(x + sqrt(Float64(Float64(x * x) + 1.0))))
end
function tmp = code(x)
	tmp = log((x + sqrt(((x * x) + 1.0))));
end
code[x_] := N[Log[N[(x + N[Sqrt[N[(N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\log \left(x + \sqrt{x \cdot x + 1}\right)
\end{array}

Alternative 1: 99.6% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.1:\\ \;\;\;\;\log \left(\frac{\frac{0.125}{x \cdot x} - 0.5}{x}\right)\\ \mathbf{elif}\;x \leq 1.1:\\ \;\;\;\;\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(-0.044642857142857144, x \cdot x, 0.075\right), x \cdot x, -0.16666666666666666\right), x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + \left(x - \frac{-0.5}{x}\right)\right)\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -1.1)
   (log (/ (- (/ 0.125 (* x x)) 0.5) x))
   (if (<= x 1.1)
     (fma
      (pow x 3.0)
      (fma
       (fma -0.044642857142857144 (* x x) 0.075)
       (* x x)
       -0.16666666666666666)
      x)
     (log (+ x (- x (/ -0.5 x)))))))
double code(double x) {
	double tmp;
	if (x <= -1.1) {
		tmp = log((((0.125 / (x * x)) - 0.5) / x));
	} else if (x <= 1.1) {
		tmp = fma(pow(x, 3.0), fma(fma(-0.044642857142857144, (x * x), 0.075), (x * x), -0.16666666666666666), x);
	} else {
		tmp = log((x + (x - (-0.5 / x))));
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= -1.1)
		tmp = log(Float64(Float64(Float64(0.125 / Float64(x * x)) - 0.5) / x));
	elseif (x <= 1.1)
		tmp = fma((x ^ 3.0), fma(fma(-0.044642857142857144, Float64(x * x), 0.075), Float64(x * x), -0.16666666666666666), x);
	else
		tmp = log(Float64(x + Float64(x - Float64(-0.5 / x))));
	end
	return tmp
end
code[x_] := If[LessEqual[x, -1.1], N[Log[N[(N[(N[(0.125 / N[(x * x), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision] / x), $MachinePrecision]], $MachinePrecision], If[LessEqual[x, 1.1], N[(N[Power[x, 3.0], $MachinePrecision] * N[(N[(-0.044642857142857144 * N[(x * x), $MachinePrecision] + 0.075), $MachinePrecision] * N[(x * x), $MachinePrecision] + -0.16666666666666666), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(x + N[(x - N[(-0.5 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.1:\\
\;\;\;\;\log \left(\frac{\frac{0.125}{x \cdot x} - 0.5}{x}\right)\\

\mathbf{elif}\;x \leq 1.1:\\
\;\;\;\;\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(-0.044642857142857144, x \cdot x, 0.075\right), x \cdot x, -0.16666666666666666\right), x\right)\\

\mathbf{else}:\\
\;\;\;\;\log \left(x + \left(x - \frac{-0.5}{x}\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -1.1000000000000001

    1. Initial program 4.2%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around -inf

      \[\leadsto \log \color{blue}{\left(-1 \cdot \frac{\frac{1}{2} - \frac{1}{8} \cdot \frac{1}{{x}^{2}}}{x}\right)} \]
    4. Step-by-step derivation
      1. associate-*r/N/A

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

        \[\leadsto \log \color{blue}{\left(\frac{-1 \cdot \left(\frac{1}{2} - \frac{1}{8} \cdot \frac{1}{{x}^{2}}\right)}{x}\right)} \]
      3. mul-1-negN/A

        \[\leadsto \log \left(\frac{\color{blue}{\mathsf{neg}\left(\left(\frac{1}{2} - \frac{1}{8} \cdot \frac{1}{{x}^{2}}\right)\right)}}{x}\right) \]
      4. neg-sub0N/A

        \[\leadsto \log \left(\frac{\color{blue}{0 - \left(\frac{1}{2} - \frac{1}{8} \cdot \frac{1}{{x}^{2}}\right)}}{x}\right) \]
      5. associate--r-N/A

        \[\leadsto \log \left(\frac{\color{blue}{\left(0 - \frac{1}{2}\right) + \frac{1}{8} \cdot \frac{1}{{x}^{2}}}}{x}\right) \]
      6. metadata-evalN/A

        \[\leadsto \log \left(\frac{\color{blue}{\frac{-1}{2}} + \frac{1}{8} \cdot \frac{1}{{x}^{2}}}{x}\right) \]
      7. +-commutativeN/A

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

        \[\leadsto \log \left(\frac{\frac{1}{8} \cdot \frac{1}{{x}^{2}} + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}}{x}\right) \]
      9. sub-negN/A

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

        \[\leadsto \log \left(\frac{\color{blue}{\frac{1}{8} \cdot \frac{1}{{x}^{2}} - \frac{1}{2}}}{x}\right) \]
      11. associate-*r/N/A

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

        \[\leadsto \log \left(\frac{\frac{\color{blue}{\frac{1}{8}}}{{x}^{2}} - \frac{1}{2}}{x}\right) \]
      13. lower-/.f64N/A

        \[\leadsto \log \left(\frac{\color{blue}{\frac{\frac{1}{8}}{{x}^{2}}} - \frac{1}{2}}{x}\right) \]
      14. unpow2N/A

        \[\leadsto \log \left(\frac{\frac{\frac{1}{8}}{\color{blue}{x \cdot x}} - \frac{1}{2}}{x}\right) \]
      15. lower-*.f6499.0

        \[\leadsto \log \left(\frac{\frac{0.125}{\color{blue}{x \cdot x}} - 0.5}{x}\right) \]
    5. Applied rewrites99.0%

      \[\leadsto \log \color{blue}{\left(\frac{\frac{0.125}{x \cdot x} - 0.5}{x}\right)} \]

    if -1.1000000000000001 < x < 1.1000000000000001

    1. Initial program 9.9%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{x \cdot \left(1 + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}\right)\right)} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}\right) + 1\right)} \]
      2. distribute-lft-inN/A

        \[\leadsto \color{blue}{x \cdot \left({x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}\right)\right) + x \cdot 1} \]
      3. associate-*r*N/A

        \[\leadsto \color{blue}{\left(x \cdot {x}^{2}\right) \cdot \left({x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}\right)} + x \cdot 1 \]
      4. *-rgt-identityN/A

        \[\leadsto \left(x \cdot {x}^{2}\right) \cdot \left({x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}\right) + \color{blue}{x} \]
      5. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot {x}^{2}, {x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}, x\right)} \]
      6. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{2} \cdot x}, {x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}, x\right) \]
      7. pow-plusN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, {x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}, x\right) \]
      8. lower-pow.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, {x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}, x\right) \]
      9. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left({x}^{\color{blue}{3}}, {x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}, x\right) \]
      10. sub-negN/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{{x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}, x\right) \]
      11. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) \cdot {x}^{2}} + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right), x\right) \]
      12. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) \cdot {x}^{2} + \color{blue}{\frac{-1}{6}}, x\right) \]
      13. lower-fma.f64N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\mathsf{fma}\left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}, {x}^{2}, \frac{-1}{6}\right)}, x\right) \]
      14. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\color{blue}{\frac{-5}{112} \cdot {x}^{2} + \frac{3}{40}}, {x}^{2}, \frac{-1}{6}\right), x\right) \]
      15. lower-fma.f64N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(\frac{-5}{112}, {x}^{2}, \frac{3}{40}\right)}, {x}^{2}, \frac{-1}{6}\right), x\right) \]
      16. unpow2N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(\frac{-5}{112}, \color{blue}{x \cdot x}, \frac{3}{40}\right), {x}^{2}, \frac{-1}{6}\right), x\right) \]
      17. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(\frac{-5}{112}, \color{blue}{x \cdot x}, \frac{3}{40}\right), {x}^{2}, \frac{-1}{6}\right), x\right) \]
      18. unpow2N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(\frac{-5}{112}, x \cdot x, \frac{3}{40}\right), \color{blue}{x \cdot x}, \frac{-1}{6}\right), x\right) \]
      19. lower-*.f6499.9

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(-0.044642857142857144, x \cdot x, 0.075\right), \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
    5. Applied rewrites99.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(-0.044642857142857144, x \cdot x, 0.075\right), x \cdot x, -0.16666666666666666\right), x\right)} \]

    if 1.1000000000000001 < x

    1. Initial program 54.4%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf

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

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

        \[\leadsto \log \left(x + \left(\color{blue}{x} + x \cdot \left(\frac{1}{2} \cdot \frac{1}{{x}^{2}}\right)\right)\right) \]
      3. cancel-sign-subN/A

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

        \[\leadsto \log \left(x + \left(x - \color{blue}{\left(-1 \cdot x\right)} \cdot \left(\frac{1}{2} \cdot \frac{1}{{x}^{2}}\right)\right)\right) \]
      5. lower--.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(x + \left(x - \frac{\color{blue}{\frac{-1}{2}}}{x}\right)\right) \]
      18. lower-/.f64100.0

        \[\leadsto \log \left(x + \left(x - \color{blue}{\frac{-0.5}{x}}\right)\right) \]
    5. Applied rewrites100.0%

      \[\leadsto \log \left(x + \color{blue}{\left(x - \frac{-0.5}{x}\right)}\right) \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 2: 99.5% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.3:\\ \;\;\;\;\log \left(\frac{-0.5}{x}\right)\\ \mathbf{elif}\;x \leq 1.1:\\ \;\;\;\;\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(-0.044642857142857144, x \cdot x, 0.075\right), x \cdot x, -0.16666666666666666\right), x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + \left(x - \frac{-0.5}{x}\right)\right)\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -1.3)
   (log (/ -0.5 x))
   (if (<= x 1.1)
     (fma
      (pow x 3.0)
      (fma
       (fma -0.044642857142857144 (* x x) 0.075)
       (* x x)
       -0.16666666666666666)
      x)
     (log (+ x (- x (/ -0.5 x)))))))
double code(double x) {
	double tmp;
	if (x <= -1.3) {
		tmp = log((-0.5 / x));
	} else if (x <= 1.1) {
		tmp = fma(pow(x, 3.0), fma(fma(-0.044642857142857144, (x * x), 0.075), (x * x), -0.16666666666666666), x);
	} else {
		tmp = log((x + (x - (-0.5 / x))));
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= -1.3)
		tmp = log(Float64(-0.5 / x));
	elseif (x <= 1.1)
		tmp = fma((x ^ 3.0), fma(fma(-0.044642857142857144, Float64(x * x), 0.075), Float64(x * x), -0.16666666666666666), x);
	else
		tmp = log(Float64(x + Float64(x - Float64(-0.5 / x))));
	end
	return tmp
end
code[x_] := If[LessEqual[x, -1.3], N[Log[N[(-0.5 / x), $MachinePrecision]], $MachinePrecision], If[LessEqual[x, 1.1], N[(N[Power[x, 3.0], $MachinePrecision] * N[(N[(-0.044642857142857144 * N[(x * x), $MachinePrecision] + 0.075), $MachinePrecision] * N[(x * x), $MachinePrecision] + -0.16666666666666666), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(x + N[(x - N[(-0.5 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.3:\\
\;\;\;\;\log \left(\frac{-0.5}{x}\right)\\

\mathbf{elif}\;x \leq 1.1:\\
\;\;\;\;\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(-0.044642857142857144, x \cdot x, 0.075\right), x \cdot x, -0.16666666666666666\right), x\right)\\

\mathbf{else}:\\
\;\;\;\;\log \left(x + \left(x - \frac{-0.5}{x}\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -1.30000000000000004

    1. Initial program 4.2%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around -inf

      \[\leadsto \log \color{blue}{\left(\frac{\frac{-1}{2}}{x}\right)} \]
    4. Step-by-step derivation
      1. lower-/.f6498.3

        \[\leadsto \log \color{blue}{\left(\frac{-0.5}{x}\right)} \]
    5. Applied rewrites98.3%

      \[\leadsto \log \color{blue}{\left(\frac{-0.5}{x}\right)} \]

    if -1.30000000000000004 < x < 1.1000000000000001

    1. Initial program 9.9%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{x \cdot \left(1 + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}\right)\right)} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}\right) + 1\right)} \]
      2. distribute-lft-inN/A

        \[\leadsto \color{blue}{x \cdot \left({x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}\right)\right) + x \cdot 1} \]
      3. associate-*r*N/A

        \[\leadsto \color{blue}{\left(x \cdot {x}^{2}\right) \cdot \left({x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}\right)} + x \cdot 1 \]
      4. *-rgt-identityN/A

        \[\leadsto \left(x \cdot {x}^{2}\right) \cdot \left({x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}\right) + \color{blue}{x} \]
      5. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot {x}^{2}, {x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}, x\right)} \]
      6. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{2} \cdot x}, {x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}, x\right) \]
      7. pow-plusN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, {x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}, x\right) \]
      8. lower-pow.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, {x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}, x\right) \]
      9. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left({x}^{\color{blue}{3}}, {x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) - \frac{1}{6}, x\right) \]
      10. sub-negN/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{{x}^{2} \cdot \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}, x\right) \]
      11. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) \cdot {x}^{2}} + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right), x\right) \]
      12. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}\right) \cdot {x}^{2} + \color{blue}{\frac{-1}{6}}, x\right) \]
      13. lower-fma.f64N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\mathsf{fma}\left(\frac{3}{40} + \frac{-5}{112} \cdot {x}^{2}, {x}^{2}, \frac{-1}{6}\right)}, x\right) \]
      14. +-commutativeN/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\color{blue}{\frac{-5}{112} \cdot {x}^{2} + \frac{3}{40}}, {x}^{2}, \frac{-1}{6}\right), x\right) \]
      15. lower-fma.f64N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(\frac{-5}{112}, {x}^{2}, \frac{3}{40}\right)}, {x}^{2}, \frac{-1}{6}\right), x\right) \]
      16. unpow2N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(\frac{-5}{112}, \color{blue}{x \cdot x}, \frac{3}{40}\right), {x}^{2}, \frac{-1}{6}\right), x\right) \]
      17. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(\frac{-5}{112}, \color{blue}{x \cdot x}, \frac{3}{40}\right), {x}^{2}, \frac{-1}{6}\right), x\right) \]
      18. unpow2N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(\frac{-5}{112}, x \cdot x, \frac{3}{40}\right), \color{blue}{x \cdot x}, \frac{-1}{6}\right), x\right) \]
      19. lower-*.f6499.9

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(-0.044642857142857144, x \cdot x, 0.075\right), \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
    5. Applied rewrites99.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\mathsf{fma}\left(-0.044642857142857144, x \cdot x, 0.075\right), x \cdot x, -0.16666666666666666\right), x\right)} \]

    if 1.1000000000000001 < x

    1. Initial program 54.4%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf

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

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

        \[\leadsto \log \left(x + \left(\color{blue}{x} + x \cdot \left(\frac{1}{2} \cdot \frac{1}{{x}^{2}}\right)\right)\right) \]
      3. cancel-sign-subN/A

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

        \[\leadsto \log \left(x + \left(x - \color{blue}{\left(-1 \cdot x\right)} \cdot \left(\frac{1}{2} \cdot \frac{1}{{x}^{2}}\right)\right)\right) \]
      5. lower--.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(x + \left(x - \frac{\color{blue}{\frac{-1}{2}}}{x}\right)\right) \]
      18. lower-/.f64100.0

        \[\leadsto \log \left(x + \left(x - \color{blue}{\frac{-0.5}{x}}\right)\right) \]
    5. Applied rewrites100.0%

      \[\leadsto \log \left(x + \color{blue}{\left(x - \frac{-0.5}{x}\right)}\right) \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 3: 99.5% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.35:\\ \;\;\;\;\log \left(\frac{-0.5}{x}\right)\\ \mathbf{elif}\;x \leq 1.05:\\ \;\;\;\;\mathsf{fma}\left(x, x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right), x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + \left(x - \frac{-0.5}{x}\right)\right)\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -1.35)
   (log (/ -0.5 x))
   (if (<= x 1.05)
     (fma x (* x (* (fma (* 0.075 x) x -0.16666666666666666) x)) x)
     (log (+ x (- x (/ -0.5 x)))))))
double code(double x) {
	double tmp;
	if (x <= -1.35) {
		tmp = log((-0.5 / x));
	} else if (x <= 1.05) {
		tmp = fma(x, (x * (fma((0.075 * x), x, -0.16666666666666666) * x)), x);
	} else {
		tmp = log((x + (x - (-0.5 / x))));
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= -1.35)
		tmp = log(Float64(-0.5 / x));
	elseif (x <= 1.05)
		tmp = fma(x, Float64(x * Float64(fma(Float64(0.075 * x), x, -0.16666666666666666) * x)), x);
	else
		tmp = log(Float64(x + Float64(x - Float64(-0.5 / x))));
	end
	return tmp
end
code[x_] := If[LessEqual[x, -1.35], N[Log[N[(-0.5 / x), $MachinePrecision]], $MachinePrecision], If[LessEqual[x, 1.05], N[(x * N[(x * N[(N[(N[(0.075 * x), $MachinePrecision] * x + -0.16666666666666666), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(x + N[(x - N[(-0.5 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.35:\\
\;\;\;\;\log \left(\frac{-0.5}{x}\right)\\

\mathbf{elif}\;x \leq 1.05:\\
\;\;\;\;\mathsf{fma}\left(x, x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right), x\right)\\

\mathbf{else}:\\
\;\;\;\;\log \left(x + \left(x - \frac{-0.5}{x}\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -1.3500000000000001

    1. Initial program 4.2%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around -inf

      \[\leadsto \log \color{blue}{\left(\frac{\frac{-1}{2}}{x}\right)} \]
    4. Step-by-step derivation
      1. lower-/.f6498.3

        \[\leadsto \log \color{blue}{\left(\frac{-0.5}{x}\right)} \]
    5. Applied rewrites98.3%

      \[\leadsto \log \color{blue}{\left(\frac{-0.5}{x}\right)} \]

    if -1.3500000000000001 < x < 1.05000000000000004

    1. Initial program 9.9%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \color{blue}{x \cdot \left(1 + {x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right)} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + 1\right)} \]
      2. distribute-lft-inN/A

        \[\leadsto \color{blue}{x \cdot \left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right) + x \cdot 1} \]
      3. associate-*r*N/A

        \[\leadsto \color{blue}{\left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)} + x \cdot 1 \]
      4. *-rgt-identityN/A

        \[\leadsto \left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + \color{blue}{x} \]
      5. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot {x}^{2}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right)} \]
      6. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{2} \cdot x}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
      7. pow-plusN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
      8. lower-pow.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
      9. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left({x}^{\color{blue}{3}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
      10. sub-negN/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\frac{3}{40} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}, x\right) \]
      11. metadata-evalN/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \frac{3}{40} \cdot {x}^{2} + \color{blue}{\frac{-1}{6}}, x\right) \]
      12. lower-fma.f64N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\mathsf{fma}\left(\frac{3}{40}, {x}^{2}, \frac{-1}{6}\right)}, x\right) \]
      13. unpow2N/A

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\frac{3}{40}, \color{blue}{x \cdot x}, \frac{-1}{6}\right), x\right) \]
      14. lower-*.f6499.5

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
    5. Applied rewrites99.5%

      \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
    6. Step-by-step derivation
      1. Applied rewrites99.5%

        \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(\color{blue}{0.075}, x \cdot x, -0.16666666666666666\right), x\right) \]
      2. Step-by-step derivation
        1. Applied rewrites99.5%

          \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(0.075 \cdot x, \color{blue}{x}, -0.16666666666666666\right), x\right) \]
        2. Step-by-step derivation
          1. Applied rewrites99.5%

            \[\leadsto \mathsf{fma}\left(x, \color{blue}{x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right)}, x\right) \]

          if 1.05000000000000004 < x

          1. Initial program 54.4%

            \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
          2. Add Preprocessing
          3. Taylor expanded in x around inf

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

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

              \[\leadsto \log \left(x + \left(\color{blue}{x} + x \cdot \left(\frac{1}{2} \cdot \frac{1}{{x}^{2}}\right)\right)\right) \]
            3. cancel-sign-subN/A

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

              \[\leadsto \log \left(x + \left(x - \color{blue}{\left(-1 \cdot x\right)} \cdot \left(\frac{1}{2} \cdot \frac{1}{{x}^{2}}\right)\right)\right) \]
            5. lower--.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

              \[\leadsto \log \left(x + \left(x - \frac{\color{blue}{\frac{-1}{2}}}{x}\right)\right) \]
            18. lower-/.f64100.0

              \[\leadsto \log \left(x + \left(x - \color{blue}{\frac{-0.5}{x}}\right)\right) \]
          5. Applied rewrites100.0%

            \[\leadsto \log \left(x + \color{blue}{\left(x - \frac{-0.5}{x}\right)}\right) \]
        3. Recombined 3 regimes into one program.
        4. Add Preprocessing

        Alternative 4: 99.4% accurate, 1.0× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.35:\\ \;\;\;\;\log \left(\frac{-0.5}{x}\right)\\ \mathbf{elif}\;x \leq 1.3:\\ \;\;\;\;\mathsf{fma}\left(x, x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right), x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(2 \cdot x\right)\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= x -1.35)
           (log (/ -0.5 x))
           (if (<= x 1.3)
             (fma x (* x (* (fma (* 0.075 x) x -0.16666666666666666) x)) x)
             (log (* 2.0 x)))))
        double code(double x) {
        	double tmp;
        	if (x <= -1.35) {
        		tmp = log((-0.5 / x));
        	} else if (x <= 1.3) {
        		tmp = fma(x, (x * (fma((0.075 * x), x, -0.16666666666666666) * x)), x);
        	} else {
        		tmp = log((2.0 * x));
        	}
        	return tmp;
        }
        
        function code(x)
        	tmp = 0.0
        	if (x <= -1.35)
        		tmp = log(Float64(-0.5 / x));
        	elseif (x <= 1.3)
        		tmp = fma(x, Float64(x * Float64(fma(Float64(0.075 * x), x, -0.16666666666666666) * x)), x);
        	else
        		tmp = log(Float64(2.0 * x));
        	end
        	return tmp
        end
        
        code[x_] := If[LessEqual[x, -1.35], N[Log[N[(-0.5 / x), $MachinePrecision]], $MachinePrecision], If[LessEqual[x, 1.3], N[(x * N[(x * N[(N[(N[(0.075 * x), $MachinePrecision] * x + -0.16666666666666666), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(2.0 * x), $MachinePrecision]], $MachinePrecision]]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq -1.35:\\
        \;\;\;\;\log \left(\frac{-0.5}{x}\right)\\
        
        \mathbf{elif}\;x \leq 1.3:\\
        \;\;\;\;\mathsf{fma}\left(x, x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right), x\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\log \left(2 \cdot x\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 3 regimes
        2. if x < -1.3500000000000001

          1. Initial program 4.2%

            \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
          2. Add Preprocessing
          3. Taylor expanded in x around -inf

            \[\leadsto \log \color{blue}{\left(\frac{\frac{-1}{2}}{x}\right)} \]
          4. Step-by-step derivation
            1. lower-/.f6498.3

              \[\leadsto \log \color{blue}{\left(\frac{-0.5}{x}\right)} \]
          5. Applied rewrites98.3%

            \[\leadsto \log \color{blue}{\left(\frac{-0.5}{x}\right)} \]

          if -1.3500000000000001 < x < 1.30000000000000004

          1. Initial program 9.9%

            \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \color{blue}{x \cdot \left(1 + {x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right)} \]
          4. Step-by-step derivation
            1. +-commutativeN/A

              \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + 1\right)} \]
            2. distribute-lft-inN/A

              \[\leadsto \color{blue}{x \cdot \left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right) + x \cdot 1} \]
            3. associate-*r*N/A

              \[\leadsto \color{blue}{\left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)} + x \cdot 1 \]
            4. *-rgt-identityN/A

              \[\leadsto \left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + \color{blue}{x} \]
            5. lower-fma.f64N/A

              \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot {x}^{2}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right)} \]
            6. *-commutativeN/A

              \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{2} \cdot x}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
            7. pow-plusN/A

              \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
            8. lower-pow.f64N/A

              \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
            9. metadata-evalN/A

              \[\leadsto \mathsf{fma}\left({x}^{\color{blue}{3}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
            10. sub-negN/A

              \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\frac{3}{40} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}, x\right) \]
            11. metadata-evalN/A

              \[\leadsto \mathsf{fma}\left({x}^{3}, \frac{3}{40} \cdot {x}^{2} + \color{blue}{\frac{-1}{6}}, x\right) \]
            12. lower-fma.f64N/A

              \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\mathsf{fma}\left(\frac{3}{40}, {x}^{2}, \frac{-1}{6}\right)}, x\right) \]
            13. unpow2N/A

              \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\frac{3}{40}, \color{blue}{x \cdot x}, \frac{-1}{6}\right), x\right) \]
            14. lower-*.f6499.5

              \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
          5. Applied rewrites99.5%

            \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
          6. Step-by-step derivation
            1. Applied rewrites99.5%

              \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(\color{blue}{0.075}, x \cdot x, -0.16666666666666666\right), x\right) \]
            2. Step-by-step derivation
              1. Applied rewrites99.5%

                \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(0.075 \cdot x, \color{blue}{x}, -0.16666666666666666\right), x\right) \]
              2. Step-by-step derivation
                1. Applied rewrites99.5%

                  \[\leadsto \mathsf{fma}\left(x, \color{blue}{x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right)}, x\right) \]

                if 1.30000000000000004 < x

                1. Initial program 54.4%

                  \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                2. Add Preprocessing
                3. Taylor expanded in x around inf

                  \[\leadsto \log \color{blue}{\left(2 \cdot x\right)} \]
                4. Step-by-step derivation
                  1. lower-*.f6499.7

                    \[\leadsto \log \color{blue}{\left(2 \cdot x\right)} \]
                5. Applied rewrites99.7%

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

              Alternative 5: 74.9% accurate, 1.1× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.3:\\ \;\;\;\;\mathsf{fma}\left(x, x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right), x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(2 \cdot x\right)\\ \end{array} \end{array} \]
              (FPCore (x)
               :precision binary64
               (if (<= x 1.3)
                 (fma x (* x (* (fma (* 0.075 x) x -0.16666666666666666) x)) x)
                 (log (* 2.0 x))))
              double code(double x) {
              	double tmp;
              	if (x <= 1.3) {
              		tmp = fma(x, (x * (fma((0.075 * x), x, -0.16666666666666666) * x)), x);
              	} else {
              		tmp = log((2.0 * x));
              	}
              	return tmp;
              }
              
              function code(x)
              	tmp = 0.0
              	if (x <= 1.3)
              		tmp = fma(x, Float64(x * Float64(fma(Float64(0.075 * x), x, -0.16666666666666666) * x)), x);
              	else
              		tmp = log(Float64(2.0 * x));
              	end
              	return tmp
              end
              
              code[x_] := If[LessEqual[x, 1.3], N[(x * N[(x * N[(N[(N[(0.075 * x), $MachinePrecision] * x + -0.16666666666666666), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(2.0 * x), $MachinePrecision]], $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;x \leq 1.3:\\
              \;\;\;\;\mathsf{fma}\left(x, x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right), x\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\log \left(2 \cdot x\right)\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if x < 1.30000000000000004

                1. Initial program 8.1%

                  \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                2. Add Preprocessing
                3. Taylor expanded in x around 0

                  \[\leadsto \color{blue}{x \cdot \left(1 + {x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right)} \]
                4. Step-by-step derivation
                  1. +-commutativeN/A

                    \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + 1\right)} \]
                  2. distribute-lft-inN/A

                    \[\leadsto \color{blue}{x \cdot \left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right) + x \cdot 1} \]
                  3. associate-*r*N/A

                    \[\leadsto \color{blue}{\left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)} + x \cdot 1 \]
                  4. *-rgt-identityN/A

                    \[\leadsto \left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + \color{blue}{x} \]
                  5. lower-fma.f64N/A

                    \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot {x}^{2}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right)} \]
                  6. *-commutativeN/A

                    \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{2} \cdot x}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                  7. pow-plusN/A

                    \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                  8. lower-pow.f64N/A

                    \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                  9. metadata-evalN/A

                    \[\leadsto \mathsf{fma}\left({x}^{\color{blue}{3}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                  10. sub-negN/A

                    \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\frac{3}{40} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}, x\right) \]
                  11. metadata-evalN/A

                    \[\leadsto \mathsf{fma}\left({x}^{3}, \frac{3}{40} \cdot {x}^{2} + \color{blue}{\frac{-1}{6}}, x\right) \]
                  12. lower-fma.f64N/A

                    \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\mathsf{fma}\left(\frac{3}{40}, {x}^{2}, \frac{-1}{6}\right)}, x\right) \]
                  13. unpow2N/A

                    \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\frac{3}{40}, \color{blue}{x \cdot x}, \frac{-1}{6}\right), x\right) \]
                  14. lower-*.f6468.7

                    \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
                5. Applied rewrites68.7%

                  \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
                6. Step-by-step derivation
                  1. Applied rewrites68.7%

                    \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(\color{blue}{0.075}, x \cdot x, -0.16666666666666666\right), x\right) \]
                  2. Step-by-step derivation
                    1. Applied rewrites68.7%

                      \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(0.075 \cdot x, \color{blue}{x}, -0.16666666666666666\right), x\right) \]
                    2. Step-by-step derivation
                      1. Applied rewrites68.7%

                        \[\leadsto \mathsf{fma}\left(x, \color{blue}{x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right)}, x\right) \]

                      if 1.30000000000000004 < x

                      1. Initial program 54.4%

                        \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                      2. Add Preprocessing
                      3. Taylor expanded in x around inf

                        \[\leadsto \log \color{blue}{\left(2 \cdot x\right)} \]
                      4. Step-by-step derivation
                        1. lower-*.f6499.7

                          \[\leadsto \log \color{blue}{\left(2 \cdot x\right)} \]
                      5. Applied rewrites99.7%

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

                    Alternative 6: 58.1% accurate, 1.1× speedup?

                    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.5:\\ \;\;\;\;\mathsf{fma}\left(x, x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right), x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(1 + x\right)\\ \end{array} \end{array} \]
                    (FPCore (x)
                     :precision binary64
                     (if (<= x 1.5)
                       (fma x (* x (* (fma (* 0.075 x) x -0.16666666666666666) x)) x)
                       (log (+ 1.0 x))))
                    double code(double x) {
                    	double tmp;
                    	if (x <= 1.5) {
                    		tmp = fma(x, (x * (fma((0.075 * x), x, -0.16666666666666666) * x)), x);
                    	} else {
                    		tmp = log((1.0 + x));
                    	}
                    	return tmp;
                    }
                    
                    function code(x)
                    	tmp = 0.0
                    	if (x <= 1.5)
                    		tmp = fma(x, Float64(x * Float64(fma(Float64(0.075 * x), x, -0.16666666666666666) * x)), x);
                    	else
                    		tmp = log(Float64(1.0 + x));
                    	end
                    	return tmp
                    end
                    
                    code[x_] := If[LessEqual[x, 1.5], N[(x * N[(x * N[(N[(N[(0.075 * x), $MachinePrecision] * x + -0.16666666666666666), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]]
                    
                    \begin{array}{l}
                    
                    \\
                    \begin{array}{l}
                    \mathbf{if}\;x \leq 1.5:\\
                    \;\;\;\;\mathsf{fma}\left(x, x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right), x\right)\\
                    
                    \mathbf{else}:\\
                    \;\;\;\;\log \left(1 + x\right)\\
                    
                    
                    \end{array}
                    \end{array}
                    
                    Derivation
                    1. Split input into 2 regimes
                    2. if x < 1.5

                      1. Initial program 8.1%

                        \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                      2. Add Preprocessing
                      3. Taylor expanded in x around 0

                        \[\leadsto \color{blue}{x \cdot \left(1 + {x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right)} \]
                      4. Step-by-step derivation
                        1. +-commutativeN/A

                          \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + 1\right)} \]
                        2. distribute-lft-inN/A

                          \[\leadsto \color{blue}{x \cdot \left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right) + x \cdot 1} \]
                        3. associate-*r*N/A

                          \[\leadsto \color{blue}{\left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)} + x \cdot 1 \]
                        4. *-rgt-identityN/A

                          \[\leadsto \left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + \color{blue}{x} \]
                        5. lower-fma.f64N/A

                          \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot {x}^{2}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right)} \]
                        6. *-commutativeN/A

                          \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{2} \cdot x}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                        7. pow-plusN/A

                          \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                        8. lower-pow.f64N/A

                          \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                        9. metadata-evalN/A

                          \[\leadsto \mathsf{fma}\left({x}^{\color{blue}{3}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                        10. sub-negN/A

                          \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\frac{3}{40} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}, x\right) \]
                        11. metadata-evalN/A

                          \[\leadsto \mathsf{fma}\left({x}^{3}, \frac{3}{40} \cdot {x}^{2} + \color{blue}{\frac{-1}{6}}, x\right) \]
                        12. lower-fma.f64N/A

                          \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\mathsf{fma}\left(\frac{3}{40}, {x}^{2}, \frac{-1}{6}\right)}, x\right) \]
                        13. unpow2N/A

                          \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\frac{3}{40}, \color{blue}{x \cdot x}, \frac{-1}{6}\right), x\right) \]
                        14. lower-*.f6468.7

                          \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
                      5. Applied rewrites68.7%

                        \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
                      6. Step-by-step derivation
                        1. Applied rewrites68.7%

                          \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(\color{blue}{0.075}, x \cdot x, -0.16666666666666666\right), x\right) \]
                        2. Step-by-step derivation
                          1. Applied rewrites68.7%

                            \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(0.075 \cdot x, \color{blue}{x}, -0.16666666666666666\right), x\right) \]
                          2. Step-by-step derivation
                            1. Applied rewrites68.7%

                              \[\leadsto \mathsf{fma}\left(x, \color{blue}{x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right)}, x\right) \]

                            if 1.5 < x

                            1. Initial program 54.4%

                              \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                            2. Add Preprocessing
                            3. Taylor expanded in x around 0

                              \[\leadsto \log \color{blue}{\left(1 + x\right)} \]
                            4. Step-by-step derivation
                              1. lower-+.f6431.7

                                \[\leadsto \log \color{blue}{\left(1 + x\right)} \]
                            5. Applied rewrites31.7%

                              \[\leadsto \log \color{blue}{\left(1 + x\right)} \]
                          3. Recombined 2 regimes into one program.
                          4. Add Preprocessing

                          Alternative 7: 51.2% accurate, 4.4× speedup?

                          \[\begin{array}{l} \\ \mathsf{fma}\left(x, x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right), x\right) \end{array} \]
                          (FPCore (x)
                           :precision binary64
                           (fma x (* x (* (fma (* 0.075 x) x -0.16666666666666666) x)) x))
                          double code(double x) {
                          	return fma(x, (x * (fma((0.075 * x), x, -0.16666666666666666) * x)), x);
                          }
                          
                          function code(x)
                          	return fma(x, Float64(x * Float64(fma(Float64(0.075 * x), x, -0.16666666666666666) * x)), x)
                          end
                          
                          code[x_] := N[(x * N[(x * N[(N[(N[(0.075 * x), $MachinePrecision] * x + -0.16666666666666666), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision]
                          
                          \begin{array}{l}
                          
                          \\
                          \mathsf{fma}\left(x, x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right), x\right)
                          \end{array}
                          
                          Derivation
                          1. Initial program 17.3%

                            \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                          2. Add Preprocessing
                          3. Taylor expanded in x around 0

                            \[\leadsto \color{blue}{x \cdot \left(1 + {x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right)} \]
                          4. Step-by-step derivation
                            1. +-commutativeN/A

                              \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + 1\right)} \]
                            2. distribute-lft-inN/A

                              \[\leadsto \color{blue}{x \cdot \left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right) + x \cdot 1} \]
                            3. associate-*r*N/A

                              \[\leadsto \color{blue}{\left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)} + x \cdot 1 \]
                            4. *-rgt-identityN/A

                              \[\leadsto \left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + \color{blue}{x} \]
                            5. lower-fma.f64N/A

                              \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot {x}^{2}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right)} \]
                            6. *-commutativeN/A

                              \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{2} \cdot x}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                            7. pow-plusN/A

                              \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                            8. lower-pow.f64N/A

                              \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                            9. metadata-evalN/A

                              \[\leadsto \mathsf{fma}\left({x}^{\color{blue}{3}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                            10. sub-negN/A

                              \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\frac{3}{40} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}, x\right) \]
                            11. metadata-evalN/A

                              \[\leadsto \mathsf{fma}\left({x}^{3}, \frac{3}{40} \cdot {x}^{2} + \color{blue}{\frac{-1}{6}}, x\right) \]
                            12. lower-fma.f64N/A

                              \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\mathsf{fma}\left(\frac{3}{40}, {x}^{2}, \frac{-1}{6}\right)}, x\right) \]
                            13. unpow2N/A

                              \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\frac{3}{40}, \color{blue}{x \cdot x}, \frac{-1}{6}\right), x\right) \]
                            14. lower-*.f6455.7

                              \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
                          5. Applied rewrites55.7%

                            \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
                          6. Step-by-step derivation
                            1. Applied rewrites55.7%

                              \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(\color{blue}{0.075}, x \cdot x, -0.16666666666666666\right), x\right) \]
                            2. Step-by-step derivation
                              1. Applied rewrites55.7%

                                \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(0.075 \cdot x, \color{blue}{x}, -0.16666666666666666\right), x\right) \]
                              2. Step-by-step derivation
                                1. Applied rewrites55.7%

                                  \[\leadsto \mathsf{fma}\left(x, \color{blue}{x \cdot \left(\mathsf{fma}\left(0.075 \cdot x, x, -0.16666666666666666\right) \cdot x\right)}, x\right) \]
                                2. Add Preprocessing

                                Alternative 8: 50.9% accurate, 4.5× speedup?

                                \[\begin{array}{l} \\ \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \left(x \cdot x\right) \cdot 0.075, x\right) \end{array} \]
                                (FPCore (x) :precision binary64 (fma (* (* x x) x) (* (* x x) 0.075) x))
                                double code(double x) {
                                	return fma(((x * x) * x), ((x * x) * 0.075), x);
                                }
                                
                                function code(x)
                                	return fma(Float64(Float64(x * x) * x), Float64(Float64(x * x) * 0.075), x)
                                end
                                
                                code[x_] := N[(N[(N[(x * x), $MachinePrecision] * x), $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * 0.075), $MachinePrecision] + x), $MachinePrecision]
                                
                                \begin{array}{l}
                                
                                \\
                                \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \left(x \cdot x\right) \cdot 0.075, x\right)
                                \end{array}
                                
                                Derivation
                                1. Initial program 17.3%

                                  \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                                2. Add Preprocessing
                                3. Taylor expanded in x around 0

                                  \[\leadsto \color{blue}{x \cdot \left(1 + {x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right)} \]
                                4. Step-by-step derivation
                                  1. +-commutativeN/A

                                    \[\leadsto x \cdot \color{blue}{\left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + 1\right)} \]
                                  2. distribute-lft-inN/A

                                    \[\leadsto \color{blue}{x \cdot \left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)\right) + x \cdot 1} \]
                                  3. associate-*r*N/A

                                    \[\leadsto \color{blue}{\left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right)} + x \cdot 1 \]
                                  4. *-rgt-identityN/A

                                    \[\leadsto \left(x \cdot {x}^{2}\right) \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + \color{blue}{x} \]
                                  5. lower-fma.f64N/A

                                    \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot {x}^{2}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right)} \]
                                  6. *-commutativeN/A

                                    \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{2} \cdot x}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                                  7. pow-plusN/A

                                    \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                                  8. lower-pow.f64N/A

                                    \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                                  9. metadata-evalN/A

                                    \[\leadsto \mathsf{fma}\left({x}^{\color{blue}{3}}, \frac{3}{40} \cdot {x}^{2} - \frac{1}{6}, x\right) \]
                                  10. sub-negN/A

                                    \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\frac{3}{40} \cdot {x}^{2} + \left(\mathsf{neg}\left(\frac{1}{6}\right)\right)}, x\right) \]
                                  11. metadata-evalN/A

                                    \[\leadsto \mathsf{fma}\left({x}^{3}, \frac{3}{40} \cdot {x}^{2} + \color{blue}{\frac{-1}{6}}, x\right) \]
                                  12. lower-fma.f64N/A

                                    \[\leadsto \mathsf{fma}\left({x}^{3}, \color{blue}{\mathsf{fma}\left(\frac{3}{40}, {x}^{2}, \frac{-1}{6}\right)}, x\right) \]
                                  13. unpow2N/A

                                    \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(\frac{3}{40}, \color{blue}{x \cdot x}, \frac{-1}{6}\right), x\right) \]
                                  14. lower-*.f6455.7

                                    \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
                                5. Applied rewrites55.7%

                                  \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
                                6. Step-by-step derivation
                                  1. Applied rewrites55.7%

                                    \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(\color{blue}{0.075}, x \cdot x, -0.16666666666666666\right), x\right) \]
                                  2. Taylor expanded in x around inf

                                    \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{3}{40} \cdot \color{blue}{{x}^{2}}, x\right) \]
                                  3. Step-by-step derivation
                                    1. Applied rewrites54.7%

                                      \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \left(x \cdot x\right) \cdot \color{blue}{0.075}, x\right) \]
                                    2. Add Preprocessing

                                    Alternative 9: 49.7% accurate, 7.2× speedup?

                                    \[\begin{array}{l} \\ \mathsf{fma}\left(-0.16666666666666666 \cdot \left(x \cdot x\right), x, x\right) \end{array} \]
                                    (FPCore (x) :precision binary64 (fma (* -0.16666666666666666 (* x x)) x x))
                                    double code(double x) {
                                    	return fma((-0.16666666666666666 * (x * x)), x, x);
                                    }
                                    
                                    function code(x)
                                    	return fma(Float64(-0.16666666666666666 * Float64(x * x)), x, x)
                                    end
                                    
                                    code[x_] := N[(N[(-0.16666666666666666 * N[(x * x), $MachinePrecision]), $MachinePrecision] * x + x), $MachinePrecision]
                                    
                                    \begin{array}{l}
                                    
                                    \\
                                    \mathsf{fma}\left(-0.16666666666666666 \cdot \left(x \cdot x\right), x, x\right)
                                    \end{array}
                                    
                                    Derivation
                                    1. Initial program 17.3%

                                      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                                    2. Add Preprocessing
                                    3. Taylor expanded in x around 0

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

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

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

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

                                        \[\leadsto \color{blue}{\left(x \cdot {x}^{2}\right) \cdot \frac{-1}{6}} + x \cdot 1 \]
                                      5. *-rgt-identityN/A

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

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

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

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

                                        \[\leadsto \mathsf{fma}\left(\color{blue}{{x}^{\left(2 + 1\right)}}, \frac{-1}{6}, x\right) \]
                                      10. metadata-eval54.1

                                        \[\leadsto \mathsf{fma}\left({x}^{\color{blue}{3}}, -0.16666666666666666, x\right) \]
                                    5. Applied rewrites54.1%

                                      \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, -0.16666666666666666, x\right)} \]
                                    6. Step-by-step derivation
                                      1. Applied rewrites54.1%

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

                                      Developer Target 1: 30.6% accurate, 0.9× speedup?

                                      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{x \cdot x + 1}\\ \mathbf{if}\;x < 0:\\ \;\;\;\;\log \left(\frac{-1}{x - t\_0}\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + t\_0\right)\\ \end{array} \end{array} \]
                                      (FPCore (x)
                                       :precision binary64
                                       (let* ((t_0 (sqrt (+ (* x x) 1.0))))
                                         (if (< x 0.0) (log (/ -1.0 (- x t_0))) (log (+ x t_0)))))
                                      double code(double x) {
                                      	double t_0 = sqrt(((x * x) + 1.0));
                                      	double tmp;
                                      	if (x < 0.0) {
                                      		tmp = log((-1.0 / (x - t_0)));
                                      	} else {
                                      		tmp = log((x + t_0));
                                      	}
                                      	return tmp;
                                      }
                                      
                                      real(8) function code(x)
                                          real(8), intent (in) :: x
                                          real(8) :: t_0
                                          real(8) :: tmp
                                          t_0 = sqrt(((x * x) + 1.0d0))
                                          if (x < 0.0d0) then
                                              tmp = log(((-1.0d0) / (x - t_0)))
                                          else
                                              tmp = log((x + t_0))
                                          end if
                                          code = tmp
                                      end function
                                      
                                      public static double code(double x) {
                                      	double t_0 = Math.sqrt(((x * x) + 1.0));
                                      	double tmp;
                                      	if (x < 0.0) {
                                      		tmp = Math.log((-1.0 / (x - t_0)));
                                      	} else {
                                      		tmp = Math.log((x + t_0));
                                      	}
                                      	return tmp;
                                      }
                                      
                                      def code(x):
                                      	t_0 = math.sqrt(((x * x) + 1.0))
                                      	tmp = 0
                                      	if x < 0.0:
                                      		tmp = math.log((-1.0 / (x - t_0)))
                                      	else:
                                      		tmp = math.log((x + t_0))
                                      	return tmp
                                      
                                      function code(x)
                                      	t_0 = sqrt(Float64(Float64(x * x) + 1.0))
                                      	tmp = 0.0
                                      	if (x < 0.0)
                                      		tmp = log(Float64(-1.0 / Float64(x - t_0)));
                                      	else
                                      		tmp = log(Float64(x + t_0));
                                      	end
                                      	return tmp
                                      end
                                      
                                      function tmp_2 = code(x)
                                      	t_0 = sqrt(((x * x) + 1.0));
                                      	tmp = 0.0;
                                      	if (x < 0.0)
                                      		tmp = log((-1.0 / (x - t_0)));
                                      	else
                                      		tmp = log((x + t_0));
                                      	end
                                      	tmp_2 = tmp;
                                      end
                                      
                                      code[x_] := Block[{t$95$0 = N[Sqrt[N[(N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision]}, If[Less[x, 0.0], N[Log[N[(-1.0 / N[(x - t$95$0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[Log[N[(x + t$95$0), $MachinePrecision]], $MachinePrecision]]]
                                      
                                      \begin{array}{l}
                                      
                                      \\
                                      \begin{array}{l}
                                      t_0 := \sqrt{x \cdot x + 1}\\
                                      \mathbf{if}\;x < 0:\\
                                      \;\;\;\;\log \left(\frac{-1}{x - t\_0}\right)\\
                                      
                                      \mathbf{else}:\\
                                      \;\;\;\;\log \left(x + t\_0\right)\\
                                      
                                      
                                      \end{array}
                                      \end{array}
                                      

                                      Reproduce

                                      ?
                                      herbie shell --seed 2024309 
                                      (FPCore (x)
                                        :name "Hyperbolic arcsine"
                                        :precision binary64
                                      
                                        :alt
                                        (! :herbie-platform default (if (< x 0) (log (/ -1 (- x (sqrt (+ (* x x) 1))))) (log (+ x (sqrt (+ (* x x) 1))))))
                                      
                                        (log (+ x (sqrt (+ (* x x) 1.0)))))