Asymptote C

Percentage Accurate: 54.9% → 99.6%
Time: 7.7s
Alternatives: 9
Speedup: 0.7×

Specification

?
\[\begin{array}{l} \\ \frac{x}{x + 1} - \frac{x + 1}{x - 1} \end{array} \]
(FPCore (x) :precision binary64 (- (/ x (+ x 1.0)) (/ (+ x 1.0) (- x 1.0))))
double code(double x) {
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x / (x + 1.0d0)) - ((x + 1.0d0) / (x - 1.0d0))
end function
public static double code(double x) {
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
def code(x):
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0))
function code(x)
	return Float64(Float64(x / Float64(x + 1.0)) - Float64(Float64(x + 1.0) / Float64(x - 1.0)))
end
function tmp = code(x)
	tmp = (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
end
code[x_] := N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(N[(x + 1.0), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x}{x + 1} - \frac{x + 1}{x - 1}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 9 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 54.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{x}{x + 1} - \frac{x + 1}{x - 1} \end{array} \]
(FPCore (x) :precision binary64 (- (/ x (+ x 1.0)) (/ (+ x 1.0) (- x 1.0))))
double code(double x) {
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x / (x + 1.0d0)) - ((x + 1.0d0) / (x - 1.0d0))
end function
public static double code(double x) {
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
def code(x):
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0))
function code(x)
	return Float64(Float64(x / Float64(x + 1.0)) - Float64(Float64(x + 1.0) / Float64(x - 1.0)))
end
function tmp = code(x)
	tmp = (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
end
code[x_] := N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(N[(x + 1.0), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x}{x + 1} - \frac{x + 1}{x - 1}
\end{array}

Alternative 1: 99.6% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{x}{x + 1} + \frac{-1 - x}{x + -1}\\ \mathbf{if}\;t\_0 \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{\left(3 + \frac{1}{x}\right) \cdot \left(-1 + \frac{-1}{x \cdot x}\right)}{x}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (+ (/ x (+ x 1.0)) (/ (- -1.0 x) (+ x -1.0)))))
   (if (<= t_0 4e-12)
     (/ (* (+ 3.0 (/ 1.0 x)) (+ -1.0 (/ -1.0 (* x x)))) x)
     t_0)))
double code(double x) {
	double t_0 = (x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0));
	double tmp;
	if (t_0 <= 4e-12) {
		tmp = ((3.0 + (1.0 / x)) * (-1.0 + (-1.0 / (x * x)))) / x;
	} else {
		tmp = t_0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    real(8) :: tmp
    t_0 = (x / (x + 1.0d0)) + (((-1.0d0) - x) / (x + (-1.0d0)))
    if (t_0 <= 4d-12) then
        tmp = ((3.0d0 + (1.0d0 / x)) * ((-1.0d0) + ((-1.0d0) / (x * x)))) / x
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x) {
	double t_0 = (x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0));
	double tmp;
	if (t_0 <= 4e-12) {
		tmp = ((3.0 + (1.0 / x)) * (-1.0 + (-1.0 / (x * x)))) / x;
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x):
	t_0 = (x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0))
	tmp = 0
	if t_0 <= 4e-12:
		tmp = ((3.0 + (1.0 / x)) * (-1.0 + (-1.0 / (x * x)))) / x
	else:
		tmp = t_0
	return tmp
function code(x)
	t_0 = Float64(Float64(x / Float64(x + 1.0)) + Float64(Float64(-1.0 - x) / Float64(x + -1.0)))
	tmp = 0.0
	if (t_0 <= 4e-12)
		tmp = Float64(Float64(Float64(3.0 + Float64(1.0 / x)) * Float64(-1.0 + Float64(-1.0 / Float64(x * x)))) / x);
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x)
	t_0 = (x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0));
	tmp = 0.0;
	if (t_0 <= 4e-12)
		tmp = ((3.0 + (1.0 / x)) * (-1.0 + (-1.0 / (x * x)))) / x;
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_] := Block[{t$95$0 = N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] + N[(N[(-1.0 - x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 4e-12], N[(N[(N[(3.0 + N[(1.0 / x), $MachinePrecision]), $MachinePrecision] * N[(-1.0 + N[(-1.0 / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision], t$95$0]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{x}{x + 1} + \frac{-1 - x}{x + -1}\\
\mathbf{if}\;t\_0 \leq 4 \cdot 10^{-12}:\\
\;\;\;\;\frac{\left(3 + \frac{1}{x}\right) \cdot \left(-1 + \frac{-1}{x \cdot x}\right)}{x}\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 3.99999999999999992e-12

    1. Initial program 7.4%

      \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf

      \[\leadsto \color{blue}{\frac{-1 \cdot \frac{3 + \frac{1}{x}}{{x}^{2}} - \left(3 + \frac{1}{x}\right)}{x}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{-1 \cdot \frac{3 + \frac{1}{x}}{{x}^{2}} - \left(3 + \frac{1}{x}\right)}{x}} \]
    5. Applied rewrites99.4%

      \[\leadsto \color{blue}{\frac{\left(3 + \frac{1}{x}\right) \cdot \left(-1 + \frac{-1}{x \cdot x}\right)}{x}} \]

    if 3.99999999999999992e-12 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64))))

    1. Initial program 100.0%

      \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
    2. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification99.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{\left(3 + \frac{1}{x}\right) \cdot \left(-1 + \frac{-1}{x \cdot x}\right)}{x}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1}\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 99.6% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{x}{x + 1} + \frac{-1 - x}{x + -1}\\ \mathbf{if}\;t\_0 \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3 + \frac{-3 - x}{x \cdot x}}{x}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (+ (/ x (+ x 1.0)) (/ (- -1.0 x) (+ x -1.0)))))
   (if (<= t_0 4e-12) (/ (+ -3.0 (/ (- -3.0 x) (* x x))) x) t_0)))
double code(double x) {
	double t_0 = (x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0));
	double tmp;
	if (t_0 <= 4e-12) {
		tmp = (-3.0 + ((-3.0 - x) / (x * x))) / x;
	} else {
		tmp = t_0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    real(8) :: tmp
    t_0 = (x / (x + 1.0d0)) + (((-1.0d0) - x) / (x + (-1.0d0)))
    if (t_0 <= 4d-12) then
        tmp = ((-3.0d0) + (((-3.0d0) - x) / (x * x))) / x
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x) {
	double t_0 = (x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0));
	double tmp;
	if (t_0 <= 4e-12) {
		tmp = (-3.0 + ((-3.0 - x) / (x * x))) / x;
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x):
	t_0 = (x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0))
	tmp = 0
	if t_0 <= 4e-12:
		tmp = (-3.0 + ((-3.0 - x) / (x * x))) / x
	else:
		tmp = t_0
	return tmp
function code(x)
	t_0 = Float64(Float64(x / Float64(x + 1.0)) + Float64(Float64(-1.0 - x) / Float64(x + -1.0)))
	tmp = 0.0
	if (t_0 <= 4e-12)
		tmp = Float64(Float64(-3.0 + Float64(Float64(-3.0 - x) / Float64(x * x))) / x);
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x)
	t_0 = (x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0));
	tmp = 0.0;
	if (t_0 <= 4e-12)
		tmp = (-3.0 + ((-3.0 - x) / (x * x))) / x;
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_] := Block[{t$95$0 = N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] + N[(N[(-1.0 - x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 4e-12], N[(N[(-3.0 + N[(N[(-3.0 - x), $MachinePrecision] / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision], t$95$0]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{x}{x + 1} + \frac{-1 - x}{x + -1}\\
\mathbf{if}\;t\_0 \leq 4 \cdot 10^{-12}:\\
\;\;\;\;\frac{-3 + \frac{-3 - x}{x \cdot x}}{x}\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 3.99999999999999992e-12

    1. Initial program 7.4%

      \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf

      \[\leadsto \color{blue}{\frac{-1 \cdot \frac{3 + \frac{1}{x}}{{x}^{2}} - \left(3 + \frac{1}{x}\right)}{x}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{-1 \cdot \frac{3 + \frac{1}{x}}{{x}^{2}} - \left(3 + \frac{1}{x}\right)}{x}} \]
    5. Applied rewrites99.4%

      \[\leadsto \color{blue}{\frac{\left(3 + \frac{1}{x}\right) \cdot \left(-1 + \frac{-1}{x \cdot x}\right)}{x}} \]
    6. Taylor expanded in x around inf

      \[\leadsto \frac{-1 \cdot \frac{1 + 3 \cdot \frac{1}{x}}{x} - 3}{x} \]
    7. Step-by-step derivation
      1. Applied rewrites99.3%

        \[\leadsto \frac{-3 + \frac{-3 - x}{x \cdot x}}{x} \]

      if 3.99999999999999992e-12 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64))))

      1. Initial program 100.0%

        \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
      2. Add Preprocessing
    8. Recombined 2 regimes into one program.
    9. Final simplification99.7%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3 + \frac{-3 - x}{x \cdot x}}{x}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1}\\ \end{array} \]
    10. Add Preprocessing

    Alternative 3: 98.7% accurate, 0.5× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3 + \frac{-3 - x}{x \cdot x}}{x}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)\\ \end{array} \end{array} \]
    (FPCore (x)
     :precision binary64
     (if (<= (+ (/ x (+ x 1.0)) (/ (- -1.0 x) (+ x -1.0))) 4e-12)
       (/ (+ -3.0 (/ (- -3.0 x) (* x x))) x)
       (* (fma 3.0 x 1.0) (fma x x 1.0))))
    double code(double x) {
    	double tmp;
    	if (((x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0))) <= 4e-12) {
    		tmp = (-3.0 + ((-3.0 - x) / (x * x))) / x;
    	} else {
    		tmp = fma(3.0, x, 1.0) * fma(x, x, 1.0);
    	}
    	return tmp;
    }
    
    function code(x)
    	tmp = 0.0
    	if (Float64(Float64(x / Float64(x + 1.0)) + Float64(Float64(-1.0 - x) / Float64(x + -1.0))) <= 4e-12)
    		tmp = Float64(Float64(-3.0 + Float64(Float64(-3.0 - x) / Float64(x * x))) / x);
    	else
    		tmp = Float64(fma(3.0, x, 1.0) * fma(x, x, 1.0));
    	end
    	return tmp
    end
    
    code[x_] := If[LessEqual[N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] + N[(N[(-1.0 - x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 4e-12], N[(N[(-3.0 + N[(N[(-3.0 - x), $MachinePrecision] / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision], N[(N[(3.0 * x + 1.0), $MachinePrecision] * N[(x * x + 1.0), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\
    \;\;\;\;\frac{-3 + \frac{-3 - x}{x \cdot x}}{x}\\
    
    \mathbf{else}:\\
    \;\;\;\;\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 3.99999999999999992e-12

      1. Initial program 7.4%

        \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
      2. Add Preprocessing
      3. Taylor expanded in x around inf

        \[\leadsto \color{blue}{\frac{-1 \cdot \frac{3 + \frac{1}{x}}{{x}^{2}} - \left(3 + \frac{1}{x}\right)}{x}} \]
      4. Step-by-step derivation
        1. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{-1 \cdot \frac{3 + \frac{1}{x}}{{x}^{2}} - \left(3 + \frac{1}{x}\right)}{x}} \]
      5. Applied rewrites99.4%

        \[\leadsto \color{blue}{\frac{\left(3 + \frac{1}{x}\right) \cdot \left(-1 + \frac{-1}{x \cdot x}\right)}{x}} \]
      6. Taylor expanded in x around inf

        \[\leadsto \frac{-1 \cdot \frac{1 + 3 \cdot \frac{1}{x}}{x} - 3}{x} \]
      7. Step-by-step derivation
        1. Applied rewrites99.3%

          \[\leadsto \frac{-3 + \frac{-3 - x}{x \cdot x}}{x} \]

        if 3.99999999999999992e-12 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64))))

        1. Initial program 100.0%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \color{blue}{1 + x \cdot \left(3 + x \cdot \left(1 + 3 \cdot x\right)\right)} \]
        4. Step-by-step derivation
          1. distribute-lft-inN/A

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

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

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

            \[\leadsto \left(1 + 3 \cdot x\right) + \color{blue}{\left(x \cdot x\right) \cdot \left(1 + 3 \cdot x\right)} \]
          5. unpow2N/A

            \[\leadsto \left(1 + 3 \cdot x\right) + \color{blue}{{x}^{2}} \cdot \left(1 + 3 \cdot x\right) \]
          6. distribute-rgt1-inN/A

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

            \[\leadsto \color{blue}{\left(1 + 3 \cdot x\right) \cdot \left({x}^{2} + 1\right)} \]
          8. lower-*.f64N/A

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

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

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

            \[\leadsto \mathsf{fma}\left(3, x, 1\right) \cdot \left(\color{blue}{x \cdot x} + 1\right) \]
          12. lower-fma.f6499.6

            \[\leadsto \mathsf{fma}\left(3, x, 1\right) \cdot \color{blue}{\mathsf{fma}\left(x, x, 1\right)} \]
        5. Applied rewrites99.6%

          \[\leadsto \color{blue}{\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)} \]
      8. Recombined 2 regimes into one program.
      9. Final simplification99.5%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3 + \frac{-3 - x}{x \cdot x}}{x}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)\\ \end{array} \]
      10. Add Preprocessing

      Alternative 4: 98.6% accurate, 0.5× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3 + \frac{-1}{x}}{x}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)\\ \end{array} \end{array} \]
      (FPCore (x)
       :precision binary64
       (if (<= (+ (/ x (+ x 1.0)) (/ (- -1.0 x) (+ x -1.0))) 4e-12)
         (/ (+ -3.0 (/ -1.0 x)) x)
         (* (fma 3.0 x 1.0) (fma x x 1.0))))
      double code(double x) {
      	double tmp;
      	if (((x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0))) <= 4e-12) {
      		tmp = (-3.0 + (-1.0 / x)) / x;
      	} else {
      		tmp = fma(3.0, x, 1.0) * fma(x, x, 1.0);
      	}
      	return tmp;
      }
      
      function code(x)
      	tmp = 0.0
      	if (Float64(Float64(x / Float64(x + 1.0)) + Float64(Float64(-1.0 - x) / Float64(x + -1.0))) <= 4e-12)
      		tmp = Float64(Float64(-3.0 + Float64(-1.0 / x)) / x);
      	else
      		tmp = Float64(fma(3.0, x, 1.0) * fma(x, x, 1.0));
      	end
      	return tmp
      end
      
      code[x_] := If[LessEqual[N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] + N[(N[(-1.0 - x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 4e-12], N[(N[(-3.0 + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision], N[(N[(3.0 * x + 1.0), $MachinePrecision] * N[(x * x + 1.0), $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\
      \;\;\;\;\frac{-3 + \frac{-1}{x}}{x}\\
      
      \mathbf{else}:\\
      \;\;\;\;\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 3.99999999999999992e-12

        1. Initial program 7.4%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Add Preprocessing
        3. Taylor expanded in x around inf

          \[\leadsto \color{blue}{-1 \cdot \frac{3 + \frac{1}{x}}{x}} \]
        4. Step-by-step derivation
          1. associate-*r/N/A

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

            \[\leadsto \color{blue}{\frac{-1 \cdot \left(3 + \frac{1}{x}\right)}{x}} \]
          3. neg-mul-1N/A

            \[\leadsto \frac{\color{blue}{\mathsf{neg}\left(\left(3 + \frac{1}{x}\right)\right)}}{x} \]
          4. distribute-neg-inN/A

            \[\leadsto \frac{\color{blue}{\left(\mathsf{neg}\left(3\right)\right) + \left(\mathsf{neg}\left(\frac{1}{x}\right)\right)}}{x} \]
          5. metadata-evalN/A

            \[\leadsto \frac{\color{blue}{-3} + \left(\mathsf{neg}\left(\frac{1}{x}\right)\right)}{x} \]
          6. lower-+.f64N/A

            \[\leadsto \frac{\color{blue}{-3 + \left(\mathsf{neg}\left(\frac{1}{x}\right)\right)}}{x} \]
          7. distribute-neg-fracN/A

            \[\leadsto \frac{-3 + \color{blue}{\frac{\mathsf{neg}\left(1\right)}{x}}}{x} \]
          8. metadata-evalN/A

            \[\leadsto \frac{-3 + \frac{\color{blue}{-1}}{x}}{x} \]
          9. lower-/.f6499.1

            \[\leadsto \frac{-3 + \color{blue}{\frac{-1}{x}}}{x} \]
        5. Applied rewrites99.1%

          \[\leadsto \color{blue}{\frac{-3 + \frac{-1}{x}}{x}} \]

        if 3.99999999999999992e-12 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64))))

        1. Initial program 100.0%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \color{blue}{1 + x \cdot \left(3 + x \cdot \left(1 + 3 \cdot x\right)\right)} \]
        4. Step-by-step derivation
          1. distribute-lft-inN/A

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

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

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

            \[\leadsto \left(1 + 3 \cdot x\right) + \color{blue}{\left(x \cdot x\right) \cdot \left(1 + 3 \cdot x\right)} \]
          5. unpow2N/A

            \[\leadsto \left(1 + 3 \cdot x\right) + \color{blue}{{x}^{2}} \cdot \left(1 + 3 \cdot x\right) \]
          6. distribute-rgt1-inN/A

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

            \[\leadsto \color{blue}{\left(1 + 3 \cdot x\right) \cdot \left({x}^{2} + 1\right)} \]
          8. lower-*.f64N/A

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

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

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

            \[\leadsto \mathsf{fma}\left(3, x, 1\right) \cdot \left(\color{blue}{x \cdot x} + 1\right) \]
          12. lower-fma.f6499.6

            \[\leadsto \mathsf{fma}\left(3, x, 1\right) \cdot \color{blue}{\mathsf{fma}\left(x, x, 1\right)} \]
        5. Applied rewrites99.6%

          \[\leadsto \color{blue}{\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification99.4%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3 + \frac{-1}{x}}{x}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)\\ \end{array} \]
      5. Add Preprocessing

      Alternative 5: 98.4% accurate, 0.6× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)\\ \end{array} \end{array} \]
      (FPCore (x)
       :precision binary64
       (if (<= (+ (/ x (+ x 1.0)) (/ (- -1.0 x) (+ x -1.0))) 4e-12)
         (/ -3.0 x)
         (* (fma 3.0 x 1.0) (fma x x 1.0))))
      double code(double x) {
      	double tmp;
      	if (((x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0))) <= 4e-12) {
      		tmp = -3.0 / x;
      	} else {
      		tmp = fma(3.0, x, 1.0) * fma(x, x, 1.0);
      	}
      	return tmp;
      }
      
      function code(x)
      	tmp = 0.0
      	if (Float64(Float64(x / Float64(x + 1.0)) + Float64(Float64(-1.0 - x) / Float64(x + -1.0))) <= 4e-12)
      		tmp = Float64(-3.0 / x);
      	else
      		tmp = Float64(fma(3.0, x, 1.0) * fma(x, x, 1.0));
      	end
      	return tmp
      end
      
      code[x_] := If[LessEqual[N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] + N[(N[(-1.0 - x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 4e-12], N[(-3.0 / x), $MachinePrecision], N[(N[(3.0 * x + 1.0), $MachinePrecision] * N[(x * x + 1.0), $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\
      \;\;\;\;\frac{-3}{x}\\
      
      \mathbf{else}:\\
      \;\;\;\;\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 3.99999999999999992e-12

        1. Initial program 7.4%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Add Preprocessing
        3. Taylor expanded in x around inf

          \[\leadsto \color{blue}{\frac{-3}{x}} \]
        4. Step-by-step derivation
          1. lower-/.f6498.8

            \[\leadsto \color{blue}{\frac{-3}{x}} \]
        5. Applied rewrites98.8%

          \[\leadsto \color{blue}{\frac{-3}{x}} \]

        if 3.99999999999999992e-12 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64))))

        1. Initial program 100.0%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \color{blue}{1 + x \cdot \left(3 + x \cdot \left(1 + 3 \cdot x\right)\right)} \]
        4. Step-by-step derivation
          1. distribute-lft-inN/A

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

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

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

            \[\leadsto \left(1 + 3 \cdot x\right) + \color{blue}{\left(x \cdot x\right) \cdot \left(1 + 3 \cdot x\right)} \]
          5. unpow2N/A

            \[\leadsto \left(1 + 3 \cdot x\right) + \color{blue}{{x}^{2}} \cdot \left(1 + 3 \cdot x\right) \]
          6. distribute-rgt1-inN/A

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

            \[\leadsto \color{blue}{\left(1 + 3 \cdot x\right) \cdot \left({x}^{2} + 1\right)} \]
          8. lower-*.f64N/A

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

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

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

            \[\leadsto \mathsf{fma}\left(3, x, 1\right) \cdot \left(\color{blue}{x \cdot x} + 1\right) \]
          12. lower-fma.f6499.6

            \[\leadsto \mathsf{fma}\left(3, x, 1\right) \cdot \color{blue}{\mathsf{fma}\left(x, x, 1\right)} \]
        5. Applied rewrites99.6%

          \[\leadsto \color{blue}{\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification99.2%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(3, x, 1\right) \cdot \mathsf{fma}\left(x, x, 1\right)\\ \end{array} \]
      5. Add Preprocessing

      Alternative 6: 98.4% accurate, 0.7× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x, 3, \mathsf{fma}\left(x, x, 1\right)\right)\\ \end{array} \end{array} \]
      (FPCore (x)
       :precision binary64
       (if (<= (+ (/ x (+ x 1.0)) (/ (- -1.0 x) (+ x -1.0))) 4e-12)
         (/ -3.0 x)
         (fma x 3.0 (fma x x 1.0))))
      double code(double x) {
      	double tmp;
      	if (((x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0))) <= 4e-12) {
      		tmp = -3.0 / x;
      	} else {
      		tmp = fma(x, 3.0, fma(x, x, 1.0));
      	}
      	return tmp;
      }
      
      function code(x)
      	tmp = 0.0
      	if (Float64(Float64(x / Float64(x + 1.0)) + Float64(Float64(-1.0 - x) / Float64(x + -1.0))) <= 4e-12)
      		tmp = Float64(-3.0 / x);
      	else
      		tmp = fma(x, 3.0, fma(x, x, 1.0));
      	end
      	return tmp
      end
      
      code[x_] := If[LessEqual[N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] + N[(N[(-1.0 - x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 4e-12], N[(-3.0 / x), $MachinePrecision], N[(x * 3.0 + N[(x * x + 1.0), $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\
      \;\;\;\;\frac{-3}{x}\\
      
      \mathbf{else}:\\
      \;\;\;\;\mathsf{fma}\left(x, 3, \mathsf{fma}\left(x, x, 1\right)\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 3.99999999999999992e-12

        1. Initial program 7.4%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Add Preprocessing
        3. Taylor expanded in x around inf

          \[\leadsto \color{blue}{\frac{-3}{x}} \]
        4. Step-by-step derivation
          1. lower-/.f6498.8

            \[\leadsto \color{blue}{\frac{-3}{x}} \]
        5. Applied rewrites98.8%

          \[\leadsto \color{blue}{\frac{-3}{x}} \]

        if 3.99999999999999992e-12 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64))))

        1. Initial program 100.0%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

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

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

            \[\leadsto \color{blue}{\mathsf{fma}\left(x, 3 + x, 1\right)} \]
          3. lower-+.f6499.4

            \[\leadsto \mathsf{fma}\left(x, \color{blue}{3 + x}, 1\right) \]
        5. Applied rewrites99.4%

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

            \[\leadsto \mathsf{fma}\left(x, \color{blue}{3}, \mathsf{fma}\left(x, x, 1\right)\right) \]
        7. Recombined 2 regimes into one program.
        8. Final simplification99.1%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x, 3, \mathsf{fma}\left(x, x, 1\right)\right)\\ \end{array} \]
        9. Add Preprocessing

        Alternative 7: 98.4% accurate, 0.7× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x, x + 3, 1\right)\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= (+ (/ x (+ x 1.0)) (/ (- -1.0 x) (+ x -1.0))) 4e-12)
           (/ -3.0 x)
           (fma x (+ x 3.0) 1.0)))
        double code(double x) {
        	double tmp;
        	if (((x / (x + 1.0)) + ((-1.0 - x) / (x + -1.0))) <= 4e-12) {
        		tmp = -3.0 / x;
        	} else {
        		tmp = fma(x, (x + 3.0), 1.0);
        	}
        	return tmp;
        }
        
        function code(x)
        	tmp = 0.0
        	if (Float64(Float64(x / Float64(x + 1.0)) + Float64(Float64(-1.0 - x) / Float64(x + -1.0))) <= 4e-12)
        		tmp = Float64(-3.0 / x);
        	else
        		tmp = fma(x, Float64(x + 3.0), 1.0);
        	end
        	return tmp
        end
        
        code[x_] := If[LessEqual[N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] + N[(N[(-1.0 - x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 4e-12], N[(-3.0 / x), $MachinePrecision], N[(x * N[(x + 3.0), $MachinePrecision] + 1.0), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\
        \;\;\;\;\frac{-3}{x}\\
        
        \mathbf{else}:\\
        \;\;\;\;\mathsf{fma}\left(x, x + 3, 1\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 3.99999999999999992e-12

          1. Initial program 7.4%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Add Preprocessing
          3. Taylor expanded in x around inf

            \[\leadsto \color{blue}{\frac{-3}{x}} \]
          4. Step-by-step derivation
            1. lower-/.f6498.8

              \[\leadsto \color{blue}{\frac{-3}{x}} \]
          5. Applied rewrites98.8%

            \[\leadsto \color{blue}{\frac{-3}{x}} \]

          if 3.99999999999999992e-12 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64))))

          1. Initial program 100.0%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

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

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

              \[\leadsto \color{blue}{\mathsf{fma}\left(x, 3 + x, 1\right)} \]
            3. lower-+.f6499.4

              \[\leadsto \mathsf{fma}\left(x, \color{blue}{3 + x}, 1\right) \]
          5. Applied rewrites99.4%

            \[\leadsto \color{blue}{\mathsf{fma}\left(x, 3 + x, 1\right)} \]
        3. Recombined 2 regimes into one program.
        4. Final simplification99.1%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x}{x + 1} + \frac{-1 - x}{x + -1} \leq 4 \cdot 10^{-12}:\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(x, x + 3, 1\right)\\ \end{array} \]
        5. Add Preprocessing

        Alternative 8: 51.6% accurate, 3.5× speedup?

        \[\begin{array}{l} \\ \mathsf{fma}\left(x, x + 3, 1\right) \end{array} \]
        (FPCore (x) :precision binary64 (fma x (+ x 3.0) 1.0))
        double code(double x) {
        	return fma(x, (x + 3.0), 1.0);
        }
        
        function code(x)
        	return fma(x, Float64(x + 3.0), 1.0)
        end
        
        code[x_] := N[(x * N[(x + 3.0), $MachinePrecision] + 1.0), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \mathsf{fma}\left(x, x + 3, 1\right)
        \end{array}
        
        Derivation
        1. Initial program 55.9%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

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

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

            \[\leadsto \color{blue}{\mathsf{fma}\left(x, 3 + x, 1\right)} \]
          3. lower-+.f6453.0

            \[\leadsto \mathsf{fma}\left(x, \color{blue}{3 + x}, 1\right) \]
        5. Applied rewrites53.0%

          \[\leadsto \color{blue}{\mathsf{fma}\left(x, 3 + x, 1\right)} \]
        6. Final simplification53.0%

          \[\leadsto \mathsf{fma}\left(x, x + 3, 1\right) \]
        7. Add Preprocessing

        Alternative 9: 51.6% accurate, 35.0× speedup?

        \[\begin{array}{l} \\ 1 \end{array} \]
        (FPCore (x) :precision binary64 1.0)
        double code(double x) {
        	return 1.0;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            code = 1.0d0
        end function
        
        public static double code(double x) {
        	return 1.0;
        }
        
        def code(x):
        	return 1.0
        
        function code(x)
        	return 1.0
        end
        
        function tmp = code(x)
        	tmp = 1.0;
        end
        
        code[x_] := 1.0
        
        \begin{array}{l}
        
        \\
        1
        \end{array}
        
        Derivation
        1. Initial program 55.9%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \color{blue}{1} \]
        4. Step-by-step derivation
          1. Applied rewrites52.9%

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

          Reproduce

          ?
          herbie shell --seed 2024221 
          (FPCore (x)
            :name "Asymptote C"
            :precision binary64
            (- (/ x (+ x 1.0)) (/ (+ x 1.0) (- x 1.0))))