Hyperbolic arcsine

Percentage Accurate: 17.9% → 99.5%
Time: 7.8s
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: 17.9% 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: 99.5% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.9:\\ \;\;\;\;\log \left(\frac{-0.5}{x}\right)\\ \mathbf{elif}\;x \leq 1.3:\\ \;\;\;\;\mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{1}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(\left(x - \frac{-0.5}{x}\right) + x\right)\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -1.9)
   (log (/ -0.5 x))
   (if (<= x 1.3)
     (fma (* (* x x) x) (/ 1.0 (fma -2.7 (* x x) -6.0)) x)
     (log (+ (- x (/ -0.5 x)) x)))))
double code(double x) {
	double tmp;
	if (x <= -1.9) {
		tmp = log((-0.5 / x));
	} else if (x <= 1.3) {
		tmp = fma(((x * x) * x), (1.0 / fma(-2.7, (x * x), -6.0)), x);
	} else {
		tmp = log(((x - (-0.5 / x)) + x));
	}
	return tmp;
}
function code(x)
	tmp = 0.0
	if (x <= -1.9)
		tmp = log(Float64(-0.5 / x));
	elseif (x <= 1.3)
		tmp = fma(Float64(Float64(x * x) * x), Float64(1.0 / fma(-2.7, Float64(x * x), -6.0)), x);
	else
		tmp = log(Float64(Float64(x - Float64(-0.5 / x)) + x));
	end
	return tmp
end
code[x_] := If[LessEqual[x, -1.9], N[Log[N[(-0.5 / x), $MachinePrecision]], $MachinePrecision], If[LessEqual[x, 1.3], N[(N[(N[(x * x), $MachinePrecision] * x), $MachinePrecision] * N[(1.0 / N[(-2.7 * N[(x * x), $MachinePrecision] + -6.0), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(N[(x - N[(-0.5 / x), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.9:\\
\;\;\;\;\log \left(\frac{-0.5}{x}\right)\\

\mathbf{elif}\;x \leq 1.3:\\
\;\;\;\;\mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{1}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -1.8999999999999999

    1. Initial program 3.3%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    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 -1.8999999999999999 < x < 1.30000000000000004

    1. Initial program 8.7%

      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
    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-*.f6499.4

        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
    5. Applied rewrites99.4%

      \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
    6. Step-by-step derivation
      1. Applied rewrites99.4%

        \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(\color{blue}{0.075}, x \cdot x, -0.16666666666666666\right), x\right) \]
      2. Step-by-step derivation
        1. Applied rewrites99.4%

          \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{1}{\color{blue}{\frac{1}{\mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right)}}}, x\right) \]
        2. Taylor expanded in x around 0

          \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{1}{\frac{-27}{10} \cdot {x}^{2} - \color{blue}{6}}, x\right) \]
        3. Step-by-step derivation
          1. Applied rewrites99.4%

            \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{1}{\mathsf{fma}\left(-2.7, \color{blue}{x \cdot x}, -6\right)}, x\right) \]

          if 1.30000000000000004 < x

          1. Initial program 46.5%

            \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
          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-rgt-inN/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

              \[\leadsto \log \left(x + \left(x - \frac{\color{blue}{\frac{-1}{2}}}{x}\right)\right) \]
            16. lower-/.f6499.9

              \[\leadsto \log \left(x + \left(x - \color{blue}{\frac{-0.5}{x}}\right)\right) \]
          5. Applied rewrites99.9%

            \[\leadsto \log \left(x + \color{blue}{\left(x - \frac{-0.5}{x}\right)}\right) \]
        4. Recombined 3 regimes into one program.
        5. Final simplification99.5%

          \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1.9:\\ \;\;\;\;\log \left(\frac{-0.5}{x}\right)\\ \mathbf{elif}\;x \leq 1.3:\\ \;\;\;\;\mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{1}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(\left(x - \frac{-0.5}{x}\right) + x\right)\\ \end{array} \]
        6. Add Preprocessing

        Alternative 2: 99.4% accurate, 1.0× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.9:\\ \;\;\;\;\log \left(\frac{-0.5}{x}\right)\\ \mathbf{elif}\;x \leq 1.9:\\ \;\;\;\;\mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{1}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(2 \cdot x\right)\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= x -1.9)
           (log (/ -0.5 x))
           (if (<= x 1.9)
             (fma (* (* x x) x) (/ 1.0 (fma -2.7 (* x x) -6.0)) x)
             (log (* 2.0 x)))))
        double code(double x) {
        	double tmp;
        	if (x <= -1.9) {
        		tmp = log((-0.5 / x));
        	} else if (x <= 1.9) {
        		tmp = fma(((x * x) * x), (1.0 / fma(-2.7, (x * x), -6.0)), x);
        	} else {
        		tmp = log((2.0 * x));
        	}
        	return tmp;
        }
        
        function code(x)
        	tmp = 0.0
        	if (x <= -1.9)
        		tmp = log(Float64(-0.5 / x));
        	elseif (x <= 1.9)
        		tmp = fma(Float64(Float64(x * x) * x), Float64(1.0 / fma(-2.7, Float64(x * x), -6.0)), x);
        	else
        		tmp = log(Float64(2.0 * x));
        	end
        	return tmp
        end
        
        code[x_] := If[LessEqual[x, -1.9], N[Log[N[(-0.5 / x), $MachinePrecision]], $MachinePrecision], If[LessEqual[x, 1.9], N[(N[(N[(x * x), $MachinePrecision] * x), $MachinePrecision] * N[(1.0 / N[(-2.7 * N[(x * x), $MachinePrecision] + -6.0), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(2.0 * x), $MachinePrecision]], $MachinePrecision]]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq -1.9:\\
        \;\;\;\;\log \left(\frac{-0.5}{x}\right)\\
        
        \mathbf{elif}\;x \leq 1.9:\\
        \;\;\;\;\mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{1}{\mathsf{fma}\left(-2.7, x \cdot x, -6\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 < -1.8999999999999999

          1. Initial program 3.3%

            \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
          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 -1.8999999999999999 < x < 1.8999999999999999

          1. Initial program 8.7%

            \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
          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-*.f6499.4

              \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
          5. Applied rewrites99.4%

            \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
          6. Step-by-step derivation
            1. Applied rewrites99.4%

              \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(\color{blue}{0.075}, x \cdot x, -0.16666666666666666\right), x\right) \]
            2. Step-by-step derivation
              1. Applied rewrites99.4%

                \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{1}{\color{blue}{\frac{1}{\mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right)}}}, x\right) \]
              2. Taylor expanded in x around 0

                \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{1}{\frac{-27}{10} \cdot {x}^{2} - \color{blue}{6}}, x\right) \]
              3. Step-by-step derivation
                1. Applied rewrites99.4%

                  \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \frac{1}{\mathsf{fma}\left(-2.7, \color{blue}{x \cdot x}, -6\right)}, x\right) \]

                if 1.8999999999999999 < x

                1. Initial program 46.5%

                  \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                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-*.f6499.4

                    \[\leadsto \log \color{blue}{\left(2 \cdot x\right)} \]
                5. Applied rewrites99.4%

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

              Alternative 3: 75.8% accurate, 1.1× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.9:\\ \;\;\;\;\mathsf{fma}\left(\frac{x}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x \cdot x, x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(2 \cdot x\right)\\ \end{array} \end{array} \]
              (FPCore (x)
               :precision binary64
               (if (<= x 1.9) (fma (/ x (fma -2.7 (* x x) -6.0)) (* x x) x) (log (* 2.0 x))))
              double code(double x) {
              	double tmp;
              	if (x <= 1.9) {
              		tmp = fma((x / fma(-2.7, (x * x), -6.0)), (x * x), x);
              	} else {
              		tmp = log((2.0 * x));
              	}
              	return tmp;
              }
              
              function code(x)
              	tmp = 0.0
              	if (x <= 1.9)
              		tmp = fma(Float64(x / fma(-2.7, Float64(x * x), -6.0)), Float64(x * x), x);
              	else
              		tmp = log(Float64(2.0 * x));
              	end
              	return tmp
              end
              
              code[x_] := If[LessEqual[x, 1.9], N[(N[(x / N[(-2.7 * N[(x * x), $MachinePrecision] + -6.0), $MachinePrecision]), $MachinePrecision] * N[(x * x), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(2.0 * x), $MachinePrecision]], $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;x \leq 1.9:\\
              \;\;\;\;\mathsf{fma}\left(\frac{x}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x \cdot x, x\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\log \left(2 \cdot x\right)\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if x < 1.8999999999999999

                1. Initial program 6.8%

                  \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                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-*.f6465.4

                    \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
                5. Applied rewrites65.4%

                  \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
                6. Step-by-step derivation
                  1. Applied rewrites65.4%

                    \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, 0.075, -0.16666666666666666\right) \cdot x, \color{blue}{x \cdot x}, x\right) \]
                  2. Step-by-step derivation
                    1. Applied rewrites65.4%

                      \[\leadsto \mathsf{fma}\left(\frac{x}{\frac{1}{\mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right)}}, \color{blue}{x} \cdot x, x\right) \]
                    2. Taylor expanded in x around 0

                      \[\leadsto \mathsf{fma}\left(\frac{x}{\frac{-27}{10} \cdot {x}^{2} - 6}, x \cdot x, x\right) \]
                    3. Step-by-step derivation
                      1. Applied rewrites65.6%

                        \[\leadsto \mathsf{fma}\left(\frac{x}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x \cdot x, x\right) \]

                      if 1.8999999999999999 < x

                      1. Initial program 46.5%

                        \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                      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-*.f6499.4

                          \[\leadsto \log \color{blue}{\left(2 \cdot x\right)} \]
                      5. Applied rewrites99.4%

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

                    Alternative 4: 58.4% accurate, 1.1× speedup?

                    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 4.6:\\ \;\;\;\;\mathsf{fma}\left(\frac{x}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x \cdot x, x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(1 + x\right)\\ \end{array} \end{array} \]
                    (FPCore (x)
                     :precision binary64
                     (if (<= x 4.6) (fma (/ x (fma -2.7 (* x x) -6.0)) (* x x) x) (log (+ 1.0 x))))
                    double code(double x) {
                    	double tmp;
                    	if (x <= 4.6) {
                    		tmp = fma((x / fma(-2.7, (x * x), -6.0)), (x * x), x);
                    	} else {
                    		tmp = log((1.0 + x));
                    	}
                    	return tmp;
                    }
                    
                    function code(x)
                    	tmp = 0.0
                    	if (x <= 4.6)
                    		tmp = fma(Float64(x / fma(-2.7, Float64(x * x), -6.0)), Float64(x * x), x);
                    	else
                    		tmp = log(Float64(1.0 + x));
                    	end
                    	return tmp
                    end
                    
                    code[x_] := If[LessEqual[x, 4.6], N[(N[(x / N[(-2.7 * N[(x * x), $MachinePrecision] + -6.0), $MachinePrecision]), $MachinePrecision] * N[(x * x), $MachinePrecision] + x), $MachinePrecision], N[Log[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]]
                    
                    \begin{array}{l}
                    
                    \\
                    \begin{array}{l}
                    \mathbf{if}\;x \leq 4.6:\\
                    \;\;\;\;\mathsf{fma}\left(\frac{x}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x \cdot x, x\right)\\
                    
                    \mathbf{else}:\\
                    \;\;\;\;\log \left(1 + x\right)\\
                    
                    
                    \end{array}
                    \end{array}
                    
                    Derivation
                    1. Split input into 2 regimes
                    2. if x < 4.5999999999999996

                      1. Initial program 6.8%

                        \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                      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-*.f6465.4

                          \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
                      5. Applied rewrites65.4%

                        \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
                      6. Step-by-step derivation
                        1. Applied rewrites65.4%

                          \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, 0.075, -0.16666666666666666\right) \cdot x, \color{blue}{x \cdot x}, x\right) \]
                        2. Step-by-step derivation
                          1. Applied rewrites65.4%

                            \[\leadsto \mathsf{fma}\left(\frac{x}{\frac{1}{\mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right)}}, \color{blue}{x} \cdot x, x\right) \]
                          2. Taylor expanded in x around 0

                            \[\leadsto \mathsf{fma}\left(\frac{x}{\frac{-27}{10} \cdot {x}^{2} - 6}, x \cdot x, x\right) \]
                          3. Step-by-step derivation
                            1. Applied rewrites65.6%

                              \[\leadsto \mathsf{fma}\left(\frac{x}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x \cdot x, x\right) \]

                            if 4.5999999999999996 < x

                            1. Initial program 46.5%

                              \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                            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 rewrites31.6%

                                \[\leadsto \log \left(x + \color{blue}{1}\right) \]
                            5. Recombined 2 regimes into one program.
                            6. Final simplification56.7%

                              \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 4.6:\\ \;\;\;\;\mathsf{fma}\left(\frac{x}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x \cdot x, x\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(1 + x\right)\\ \end{array} \]
                            7. Add Preprocessing

                            Alternative 5: 51.2% accurate, 3.6× speedup?

                            \[\begin{array}{l} \\ \mathsf{fma}\left(\frac{x}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x \cdot x, x\right) \end{array} \]
                            (FPCore (x) :precision binary64 (fma (/ x (fma -2.7 (* x x) -6.0)) (* x x) x))
                            double code(double x) {
                            	return fma((x / fma(-2.7, (x * x), -6.0)), (x * x), x);
                            }
                            
                            function code(x)
                            	return fma(Float64(x / fma(-2.7, Float64(x * x), -6.0)), Float64(x * x), x)
                            end
                            
                            code[x_] := N[(N[(x / N[(-2.7 * N[(x * x), $MachinePrecision] + -6.0), $MachinePrecision]), $MachinePrecision] * N[(x * x), $MachinePrecision] + x), $MachinePrecision]
                            
                            \begin{array}{l}
                            
                            \\
                            \mathsf{fma}\left(\frac{x}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x \cdot x, x\right)
                            \end{array}
                            
                            Derivation
                            1. Initial program 17.2%

                              \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                            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-*.f6449.2

                                \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
                            5. Applied rewrites49.2%

                              \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
                            6. Step-by-step derivation
                              1. Applied rewrites49.2%

                                \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, 0.075, -0.16666666666666666\right) \cdot x, \color{blue}{x \cdot x}, x\right) \]
                              2. Step-by-step derivation
                                1. Applied rewrites49.2%

                                  \[\leadsto \mathsf{fma}\left(\frac{x}{\frac{1}{\mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right)}}, \color{blue}{x} \cdot x, x\right) \]
                                2. Taylor expanded in x around 0

                                  \[\leadsto \mathsf{fma}\left(\frac{x}{\frac{-27}{10} \cdot {x}^{2} - 6}, x \cdot x, x\right) \]
                                3. Step-by-step derivation
                                  1. Applied rewrites49.3%

                                    \[\leadsto \mathsf{fma}\left(\frac{x}{\mathsf{fma}\left(-2.7, x \cdot x, -6\right)}, x \cdot x, x\right) \]
                                  2. Add Preprocessing

                                  Alternative 6: 51.3% accurate, 4.4× speedup?

                                  \[\begin{array}{l} \\ \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right) \end{array} \]
                                  (FPCore (x)
                                   :precision binary64
                                   (fma (* (* x x) x) (fma 0.075 (* x x) -0.16666666666666666) x))
                                  double code(double x) {
                                  	return fma(((x * x) * x), fma(0.075, (x * x), -0.16666666666666666), x);
                                  }
                                  
                                  function code(x)
                                  	return fma(Float64(Float64(x * x) * x), fma(0.075, Float64(x * x), -0.16666666666666666), x)
                                  end
                                  
                                  code[x_] := N[(N[(N[(x * x), $MachinePrecision] * x), $MachinePrecision] * N[(0.075 * N[(x * x), $MachinePrecision] + -0.16666666666666666), $MachinePrecision] + x), $MachinePrecision]
                                  
                                  \begin{array}{l}
                                  
                                  \\
                                  \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)
                                  \end{array}
                                  
                                  Derivation
                                  1. Initial program 17.2%

                                    \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                                  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-*.f6449.2

                                      \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
                                  5. Applied rewrites49.2%

                                    \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
                                  6. Step-by-step derivation
                                    1. Applied rewrites49.2%

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

                                    Alternative 7: 50.9% accurate, 4.5× speedup?

                                    \[\begin{array}{l} \\ \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, 0.075 \cdot \left(x \cdot x\right), x\right) \end{array} \]
                                    (FPCore (x) :precision binary64 (fma (* (* x x) x) (* 0.075 (* x x)) x))
                                    double code(double x) {
                                    	return fma(((x * x) * x), (0.075 * (x * x)), x);
                                    }
                                    
                                    function code(x)
                                    	return fma(Float64(Float64(x * x) * x), Float64(0.075 * Float64(x * x)), x)
                                    end
                                    
                                    code[x_] := N[(N[(N[(x * x), $MachinePrecision] * x), $MachinePrecision] * N[(0.075 * N[(x * x), $MachinePrecision]), $MachinePrecision] + x), $MachinePrecision]
                                    
                                    \begin{array}{l}
                                    
                                    \\
                                    \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, 0.075 \cdot \left(x \cdot x\right), x\right)
                                    \end{array}
                                    
                                    Derivation
                                    1. Initial program 17.2%

                                      \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                                    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-*.f6449.2

                                        \[\leadsto \mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, \color{blue}{x \cdot x}, -0.16666666666666666\right), x\right) \]
                                    5. Applied rewrites49.2%

                                      \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, \mathsf{fma}\left(0.075, x \cdot x, -0.16666666666666666\right), x\right)} \]
                                    6. Step-by-step derivation
                                      1. Applied rewrites49.2%

                                        \[\leadsto \mathsf{fma}\left(\left(x \cdot x\right) \cdot x, \mathsf{fma}\left(\color{blue}{0.075}, x \cdot x, -0.16666666666666666\right), x\right) \]
                                      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 rewrites48.8%

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

                                        Alternative 8: 49.8% 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 17.2%

                                          \[\log \left(x + \sqrt{x \cdot x + 1}\right) \]
                                        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-eval47.6

                                            \[\leadsto \mathsf{fma}\left({x}^{\color{blue}{3}}, -0.16666666666666666, x\right) \]
                                        5. Applied rewrites47.6%

                                          \[\leadsto \color{blue}{\mathsf{fma}\left({x}^{3}, -0.16666666666666666, x\right)} \]
                                        6. Step-by-step derivation
                                          1. Applied rewrites47.6%

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

                                          Developer Target 1: 29.8% 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 2024254 
                                          (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)))))