Hyperbolic arcsine

Percentage Accurate: 18.6% → 99.3%
Time: 10.8s
Alternatives: 8
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 8 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: 18.6% 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: 99.3% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.06:\\ \;\;\;\;\log \left(\frac{-0.5 + \frac{0.125}{x \cdot x}}{x}\right)\\ \mathbf{elif}\;x \leq 1.25:\\ \;\;\;\;\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot -0.16666666666666666, x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x \cdot 2\right)\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -1.06)
   (log (/ (+ -0.5 (/ 0.125 (* x x))) x))
   (if (<= x 1.25)
     (fma x (* (* x x) -0.16666666666666666) x)
     (log (* x 2.0)))))
double code(double x) {
	double tmp;
	if (x <= -1.06) {
		tmp = log(((-0.5 + (0.125 / (x * x))) / x));
	} else if (x <= 1.25) {
		tmp = fma(x, ((x * x) * -0.16666666666666666), x);
	} else {
		tmp = log((x * 2.0));
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= -1.06)
		tmp = log(Float64(Float64(-0.5 + Float64(0.125 / Float64(x * x))) / x));
	elseif (x <= 1.25)
		tmp = fma(x, Float64(Float64(x * x) * -0.16666666666666666), x);
	else
		tmp = log(Float64(x * 2.0));
	end
	return tmp
end
code[x_] := If[LessEqual[x, -1.06], N[Log[N[(N[(-0.5 + N[(0.125 / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]], $MachinePrecision], If[LessEqual[x, 1.25], N[(x * N[(N[(x * x), $MachinePrecision] * -0.16666666666666666), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(x * 2.0), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.06:\\
\;\;\;\;\log \left(\frac{-0.5 + \frac{0.125}{x \cdot x}}{x}\right)\\

\mathbf{elif}\;x \leq 1.25:\\
\;\;\;\;\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot -0.16666666666666666, x\right)\\

\mathbf{else}:\\
\;\;\;\;\log \left(x \cdot 2\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -1.0600000000000001

    1. Initial program 3.2%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    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. mul-1-negN/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\frac{\frac{-1}{2} + \frac{\frac{1}{8}}{\color{blue}{x \cdot x}}}{x}\right) \]
      18. lower-*.f6499.7

        \[\leadsto \log \left(\frac{-0.5 + \frac{0.125}{\color{blue}{x \cdot x}}}{x}\right) \]
    5. Applied rewrites99.7%

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

    if -1.0600000000000001 < x < 1.25

    1. Initial program 7.3%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    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. associate-*r*N/A

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, x \cdot \frac{-1}{6}, x\right) \]
      9. lower-*.f64100.0

        \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot -0.16666666666666666}, x\right) \]
    5. Applied rewrites100.0%

      \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, x \cdot -0.16666666666666666, x\right)} \]
    6. Step-by-step derivation
      1. Applied rewrites100.0%

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

      if 1.25 < x

      1. Initial program 50.8%

        \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
      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. *-commutativeN/A

          \[\leadsto \log \color{blue}{\left(x \cdot 2\right)} \]
        2. lower-*.f64100.0

          \[\leadsto \log \color{blue}{\left(x \cdot 2\right)} \]
      5. Applied rewrites100.0%

        \[\leadsto \log \color{blue}{\left(x \cdot 2\right)} \]
    7. Recombined 3 regimes into one program.
    8. Final simplification99.9%

      \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1.06:\\ \;\;\;\;\log \left(\frac{-0.5 + \frac{0.125}{x \cdot x}}{x}\right)\\ \mathbf{elif}\;x \leq 1.25:\\ \;\;\;\;\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot -0.16666666666666666, x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x \cdot 2\right)\\ \end{array} \]
    9. Add Preprocessing

    Alternative 2: 99.2% accurate, 1.0× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.26:\\ \;\;\;\;\log \left(\frac{-0.5}{x}\right)\\ \mathbf{elif}\;x \leq 1.25:\\ \;\;\;\;\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot -0.16666666666666666, x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x \cdot 2\right)\\ \end{array} \end{array} \]
    (FPCore (x)
     :precision binary64
     (if (<= x -1.26)
       (log (/ -0.5 x))
       (if (<= x 1.25)
         (fma x (* (* x x) -0.16666666666666666) x)
         (log (* x 2.0)))))
    double code(double x) {
    	double tmp;
    	if (x <= -1.26) {
    		tmp = log((-0.5 / x));
    	} else if (x <= 1.25) {
    		tmp = fma(x, ((x * x) * -0.16666666666666666), x);
    	} else {
    		tmp = log((x * 2.0));
    	}
    	return tmp;
    }
    
    function code(x)
    	tmp = 0.0
    	if (x <= -1.26)
    		tmp = log(Float64(-0.5 / x));
    	elseif (x <= 1.25)
    		tmp = fma(x, Float64(Float64(x * x) * -0.16666666666666666), x);
    	else
    		tmp = log(Float64(x * 2.0));
    	end
    	return tmp
    end
    
    code[x_] := If[LessEqual[x, -1.26], N[Log[N[(-0.5 / x), $MachinePrecision]], $MachinePrecision], If[LessEqual[x, 1.25], N[(x * N[(N[(x * x), $MachinePrecision] * -0.16666666666666666), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(x * 2.0), $MachinePrecision]], $MachinePrecision]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;x \leq -1.26:\\
    \;\;\;\;\log \left(\frac{-0.5}{x}\right)\\
    
    \mathbf{elif}\;x \leq 1.25:\\
    \;\;\;\;\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot -0.16666666666666666, x\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;\log \left(x \cdot 2\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if x < -1.26000000000000001

      1. Initial program 3.2%

        \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
      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-/.f6499.2

          \[\leadsto \log \color{blue}{\left(\frac{-0.5}{x}\right)} \]
      5. Applied rewrites99.2%

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

      if -1.26000000000000001 < x < 1.25

      1. Initial program 7.3%

        \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
      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. associate-*r*N/A

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

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

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

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

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

          \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, x \cdot \frac{-1}{6}, x\right) \]
        9. lower-*.f64100.0

          \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot -0.16666666666666666}, x\right) \]
      5. Applied rewrites100.0%

        \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, x \cdot -0.16666666666666666, x\right)} \]
      6. Step-by-step derivation
        1. Applied rewrites100.0%

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

        if 1.25 < x

        1. Initial program 50.8%

          \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
        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. *-commutativeN/A

            \[\leadsto \log \color{blue}{\left(x \cdot 2\right)} \]
          2. lower-*.f64100.0

            \[\leadsto \log \color{blue}{\left(x \cdot 2\right)} \]
        5. Applied rewrites100.0%

          \[\leadsto \log \color{blue}{\left(x \cdot 2\right)} \]
      7. Recombined 3 regimes into one program.
      8. Final simplification99.8%

        \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1.26:\\ \;\;\;\;\log \left(\frac{-0.5}{x}\right)\\ \mathbf{elif}\;x \leq 1.25:\\ \;\;\;\;\mathsf{fma}\left(x, \left(x \cdot x\right) \cdot -0.16666666666666666, x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x \cdot 2\right)\\ \end{array} \]
      9. Add Preprocessing

      Alternative 3: 75.2% accurate, 1.1× speedup?

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

        1. Initial program 6.0%

          \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
        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

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

            \[\leadsto \color{blue}{\left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + 1\right)} \cdot x \]
          3. distribute-lft1-inN/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot \frac{3}{40}, \frac{-1}{6}\right), x \cdot \color{blue}{\left(x \cdot x\right)}, x\right) \]
          18. lower-*.f6470.2

            \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.075, -0.16666666666666666\right), x \cdot \color{blue}{\left(x \cdot x\right)}, x\right) \]
        5. Applied rewrites70.2%

          \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.075, -0.16666666666666666\right), x \cdot \left(x \cdot x\right), x\right)} \]
        6. Step-by-step derivation
          1. Applied rewrites70.2%

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

          if 1.30000000000000004 < x

          1. Initial program 50.8%

            \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
          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. *-commutativeN/A

              \[\leadsto \log \color{blue}{\left(x \cdot 2\right)} \]
            2. lower-*.f64100.0

              \[\leadsto \log \color{blue}{\left(x \cdot 2\right)} \]
          5. Applied rewrites100.0%

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

        Alternative 4: 58.0% accurate, 1.1× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.55:\\ \;\;\;\;\mathsf{fma}\left(x \cdot \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x \cdot x, x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + 1\right)\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= x 1.55)
           (fma (* x (fma 0.075 (* x x) -0.16666666666666666)) (* x x) x)
           (log (+ x 1.0))))
        double code(double x) {
        	double tmp;
        	if (x <= 1.55) {
        		tmp = fma((x * fma(0.075, (x * x), -0.16666666666666666)), (x * x), x);
        	} else {
        		tmp = log((x + 1.0));
        	}
        	return tmp;
        }
        
        function code(x)
        	tmp = 0.0
        	if (x <= 1.55)
        		tmp = fma(Float64(x * fma(0.075, Float64(x * x), -0.16666666666666666)), Float64(x * x), x);
        	else
        		tmp = log(Float64(x + 1.0));
        	end
        	return tmp
        end
        
        code[x_] := If[LessEqual[x, 1.55], N[(N[(x * N[(0.075 * N[(x * x), $MachinePrecision] + -0.16666666666666666), $MachinePrecision]), $MachinePrecision] * N[(x * x), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(x + 1.0), $MachinePrecision]], $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq 1.55:\\
        \;\;\;\;\mathsf{fma}\left(x \cdot \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x \cdot x, x\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\log \left(x + 1\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < 1.55000000000000004

          1. Initial program 6.0%

            \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
          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

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

              \[\leadsto \color{blue}{\left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + 1\right)} \cdot x \]
            3. distribute-lft1-inN/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

              \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot \frac{3}{40}, \frac{-1}{6}\right), x \cdot \color{blue}{\left(x \cdot x\right)}, x\right) \]
            18. lower-*.f6470.2

              \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.075, -0.16666666666666666\right), x \cdot \color{blue}{\left(x \cdot x\right)}, x\right) \]
          5. Applied rewrites70.2%

            \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.075, -0.16666666666666666\right), x \cdot \left(x \cdot x\right), x\right)} \]
          6. Step-by-step derivation
            1. Applied rewrites70.2%

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

            if 1.55000000000000004 < x

            1. Initial program 50.8%

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

              \[\leadsto \log \left(x + \color{blue}{1}\right) \]
            4. Step-by-step derivation
              1. Applied rewrites31.8%

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

            Alternative 5: 51.0% accurate, 4.4× speedup?

            \[\begin{array}{l} \\ \mathsf{fma}\left(x \cdot \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x \cdot x, x\right) \end{array} \]
            (FPCore (x)
             :precision binary64
             (fma (* x (fma 0.075 (* x x) -0.16666666666666666)) (* x x) x))
            double code(double x) {
            	return fma((x * fma(0.075, (x * x), -0.16666666666666666)), (x * x), x);
            }
            
            function code(x)
            	return fma(Float64(x * fma(0.075, Float64(x * x), -0.16666666666666666)), Float64(x * x), x)
            end
            
            code[x_] := N[(N[(x * N[(0.075 * N[(x * x), $MachinePrecision] + -0.16666666666666666), $MachinePrecision]), $MachinePrecision] * N[(x * x), $MachinePrecision] + x), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \mathsf{fma}\left(x \cdot \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x \cdot x, x\right)
            \end{array}
            
            Derivation
            1. Initial program 17.4%

              \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
            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

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

                \[\leadsto \color{blue}{\left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + 1\right)} \cdot x \]
              3. distribute-lft1-inN/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot \frac{3}{40}, \frac{-1}{6}\right), x \cdot \color{blue}{\left(x \cdot x\right)}, x\right) \]
              18. lower-*.f6453.2

                \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.075, -0.16666666666666666\right), x \cdot \color{blue}{\left(x \cdot x\right)}, x\right) \]
            5. Applied rewrites53.2%

              \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.075, -0.16666666666666666\right), x \cdot \left(x \cdot x\right), x\right)} \]
            6. Step-by-step derivation
              1. Applied rewrites53.2%

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

              Alternative 6: 50.6% accurate, 4.5× speedup?

              \[\begin{array}{l} \\ \mathsf{fma}\left(x \cdot \left(x \cdot 0.075\right), x \cdot \left(x \cdot x\right), x\right) \end{array} \]
              (FPCore (x) :precision binary64 (fma (* x (* x 0.075)) (* x (* x x)) x))
              double code(double x) {
              	return fma((x * (x * 0.075)), (x * (x * x)), x);
              }
              
              function code(x)
              	return fma(Float64(x * Float64(x * 0.075)), Float64(x * Float64(x * x)), x)
              end
              
              code[x_] := N[(N[(x * N[(x * 0.075), $MachinePrecision]), $MachinePrecision] * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \mathsf{fma}\left(x \cdot \left(x \cdot 0.075\right), x \cdot \left(x \cdot x\right), x\right)
              \end{array}
              
              Derivation
              1. Initial program 17.4%

                \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
              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

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

                  \[\leadsto \color{blue}{\left({x}^{2} \cdot \left(\frac{3}{40} \cdot {x}^{2} - \frac{1}{6}\right) + 1\right)} \cdot x \]
                3. distribute-lft1-inN/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                  \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot \frac{3}{40}, \frac{-1}{6}\right), x \cdot \color{blue}{\left(x \cdot x\right)}, x\right) \]
                18. lower-*.f6453.2

                  \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x, x \cdot 0.075, -0.16666666666666666\right), x \cdot \color{blue}{\left(x \cdot x\right)}, x\right) \]
              5. Applied rewrites53.2%

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

                \[\leadsto \mathsf{fma}\left(\frac{3}{40} \cdot {x}^{2}, \color{blue}{x} \cdot \left(x \cdot x\right), x\right) \]
              7. Step-by-step derivation
                1. Applied rewrites53.2%

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

                Alternative 7: 49.4% accurate, 7.2× speedup?

                \[\begin{array}{l} \\ \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot -0.16666666666666666, x\right) \end{array} \]
                (FPCore (x) :precision binary64 (fma x (* (* x x) -0.16666666666666666) x))
                double code(double x) {
                	return fma(x, ((x * x) * -0.16666666666666666), x);
                }
                
                function code(x)
                	return fma(x, Float64(Float64(x * x) * -0.16666666666666666), x)
                end
                
                code[x_] := N[(x * N[(N[(x * x), $MachinePrecision] * -0.16666666666666666), $MachinePrecision] + x), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \mathsf{fma}\left(x, \left(x \cdot x\right) \cdot -0.16666666666666666, x\right)
                \end{array}
                
                Derivation
                1. Initial program 17.4%

                  \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                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. associate-*r*N/A

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

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

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

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

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

                    \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, x \cdot \frac{-1}{6}, x\right) \]
                  9. lower-*.f6451.9

                    \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot -0.16666666666666666}, x\right) \]
                5. Applied rewrites51.9%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(x \cdot x, x \cdot -0.16666666666666666, x\right)} \]
                6. Step-by-step derivation
                  1. Applied rewrites51.9%

                    \[\leadsto \mathsf{fma}\left(x, \color{blue}{-0.16666666666666666 \cdot \left(x \cdot x\right)}, x\right) \]
                  2. Final simplification51.9%

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

                  Alternative 8: 2.9% accurate, 7.6× speedup?

                  \[\begin{array}{l} \\ x \cdot \left(x \cdot \left(x \cdot -0.16666666666666666\right)\right) \end{array} \]
                  (FPCore (x) :precision binary64 (* x (* x (* x -0.16666666666666666))))
                  double code(double x) {
                  	return x * (x * (x * -0.16666666666666666));
                  }
                  
                  real(8) function code(x)
                      real(8), intent (in) :: x
                      code = x * (x * (x * (-0.16666666666666666d0)))
                  end function
                  
                  public static double code(double x) {
                  	return x * (x * (x * -0.16666666666666666));
                  }
                  
                  def code(x):
                  	return x * (x * (x * -0.16666666666666666))
                  
                  function code(x)
                  	return Float64(x * Float64(x * Float64(x * -0.16666666666666666)))
                  end
                  
                  function tmp = code(x)
                  	tmp = x * (x * (x * -0.16666666666666666));
                  end
                  
                  code[x_] := N[(x * N[(x * N[(x * -0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  x \cdot \left(x \cdot \left(x \cdot -0.16666666666666666\right)\right)
                  \end{array}
                  
                  Derivation
                  1. Initial program 17.4%

                    \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                  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. associate-*r*N/A

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

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

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

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

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

                      \[\leadsto \mathsf{fma}\left(\color{blue}{x \cdot x}, x \cdot \frac{-1}{6}, x\right) \]
                    9. lower-*.f6451.9

                      \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{x \cdot -0.16666666666666666}, x\right) \]
                  5. Applied rewrites51.9%

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

                    \[\leadsto \frac{-1}{6} \cdot \color{blue}{{x}^{3}} \]
                  7. Step-by-step derivation
                    1. Applied rewrites2.9%

                      \[\leadsto x \cdot \color{blue}{\left(x \cdot \left(x \cdot -0.16666666666666666\right)\right)} \]
                    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 2024238 
                    (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)))))