Numeric.SpecFunctions:logGamma from math-functions-0.1.5.2, A

Percentage Accurate: 100.0% → 100.0%
Time: 5.9s
Alternatives: 10
Speedup: 1.5×

Specification

?
\[\begin{array}{l} \\ \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \end{array} \]
(FPCore (x y)
 :precision binary64
 (+ (- (* x (- y 1.0)) (* y 0.5)) 0.918938533204673))
double code(double x, double y) {
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = ((x * (y - 1.0d0)) - (y * 0.5d0)) + 0.918938533204673d0
end function
public static double code(double x, double y) {
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
}
def code(x, y):
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673
function code(x, y)
	return Float64(Float64(Float64(x * Float64(y - 1.0)) - Float64(y * 0.5)) + 0.918938533204673)
end
function tmp = code(x, y)
	tmp = ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
end
code[x_, y_] := N[(N[(N[(x * N[(y - 1.0), $MachinePrecision]), $MachinePrecision] - N[(y * 0.5), $MachinePrecision]), $MachinePrecision] + 0.918938533204673), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673
\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 10 alternatives:

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

Initial Program: 100.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \end{array} \]
(FPCore (x y)
 :precision binary64
 (+ (- (* x (- y 1.0)) (* y 0.5)) 0.918938533204673))
double code(double x, double y) {
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = ((x * (y - 1.0d0)) - (y * 0.5d0)) + 0.918938533204673d0
end function
public static double code(double x, double y) {
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
}
def code(x, y):
	return ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673
function code(x, y)
	return Float64(Float64(Float64(x * Float64(y - 1.0)) - Float64(y * 0.5)) + 0.918938533204673)
end
function tmp = code(x, y)
	tmp = ((x * (y - 1.0)) - (y * 0.5)) + 0.918938533204673;
end
code[x_, y_] := N[(N[(N[(x * N[(y - 1.0), $MachinePrecision]), $MachinePrecision] - N[(y * 0.5), $MachinePrecision]), $MachinePrecision] + 0.918938533204673), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673
\end{array}

Alternative 1: 100.0% accurate, 1.3× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(y - 1, x, \mathsf{fma}\left(-0.5, y, 0.918938533204673\right)\right) \end{array} \]
(FPCore (x y)
 :precision binary64
 (fma (- y 1.0) x (fma -0.5 y 0.918938533204673)))
double code(double x, double y) {
	return fma((y - 1.0), x, fma(-0.5, y, 0.918938533204673));
}
function code(x, y)
	return fma(Float64(y - 1.0), x, fma(-0.5, y, 0.918938533204673))
end
code[x_, y_] := N[(N[(y - 1.0), $MachinePrecision] * x + N[(-0.5 * y + 0.918938533204673), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(y - 1, x, \mathsf{fma}\left(-0.5, y, 0.918938533204673\right)\right)
\end{array}
Derivation
  1. Initial program 100.0%

    \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto \color{blue}{\left(x \cdot \left(y - 1\right) - y \cdot \frac{1}{2}\right) + \frac{918938533204673}{1000000000000000}} \]
    2. lift--.f64N/A

      \[\leadsto \color{blue}{\left(x \cdot \left(y - 1\right) - y \cdot \frac{1}{2}\right)} + \frac{918938533204673}{1000000000000000} \]
    3. associate-+l-N/A

      \[\leadsto \color{blue}{x \cdot \left(y - 1\right) - \left(y \cdot \frac{1}{2} - \frac{918938533204673}{1000000000000000}\right)} \]
    4. sub-negN/A

      \[\leadsto \color{blue}{x \cdot \left(y - 1\right) + \left(\mathsf{neg}\left(\left(y \cdot \frac{1}{2} - \frac{918938533204673}{1000000000000000}\right)\right)\right)} \]
    5. lift-*.f64N/A

      \[\leadsto \color{blue}{x \cdot \left(y - 1\right)} + \left(\mathsf{neg}\left(\left(y \cdot \frac{1}{2} - \frac{918938533204673}{1000000000000000}\right)\right)\right) \]
    6. *-commutativeN/A

      \[\leadsto \color{blue}{\left(y - 1\right) \cdot x} + \left(\mathsf{neg}\left(\left(y \cdot \frac{1}{2} - \frac{918938533204673}{1000000000000000}\right)\right)\right) \]
    7. lower-fma.f64N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(y - 1, x, \mathsf{neg}\left(\left(y \cdot \frac{1}{2} - \frac{918938533204673}{1000000000000000}\right)\right)\right)} \]
    8. neg-sub0N/A

      \[\leadsto \mathsf{fma}\left(y - 1, x, \color{blue}{0 - \left(y \cdot \frac{1}{2} - \frac{918938533204673}{1000000000000000}\right)}\right) \]
    9. associate-+l-N/A

      \[\leadsto \mathsf{fma}\left(y - 1, x, \color{blue}{\left(0 - y \cdot \frac{1}{2}\right) + \frac{918938533204673}{1000000000000000}}\right) \]
    10. neg-sub0N/A

      \[\leadsto \mathsf{fma}\left(y - 1, x, \color{blue}{\left(\mathsf{neg}\left(y \cdot \frac{1}{2}\right)\right)} + \frac{918938533204673}{1000000000000000}\right) \]
    11. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(y - 1, x, \left(\mathsf{neg}\left(\color{blue}{y \cdot \frac{1}{2}}\right)\right) + \frac{918938533204673}{1000000000000000}\right) \]
    12. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(y - 1, x, \left(\mathsf{neg}\left(\color{blue}{\frac{1}{2} \cdot y}\right)\right) + \frac{918938533204673}{1000000000000000}\right) \]
    13. distribute-lft-neg-inN/A

      \[\leadsto \mathsf{fma}\left(y - 1, x, \color{blue}{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right) \cdot y} + \frac{918938533204673}{1000000000000000}\right) \]
    14. lower-fma.f64N/A

      \[\leadsto \mathsf{fma}\left(y - 1, x, \color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(\frac{1}{2}\right), y, \frac{918938533204673}{1000000000000000}\right)}\right) \]
    15. metadata-eval100.0

      \[\leadsto \mathsf{fma}\left(y - 1, x, \mathsf{fma}\left(\color{blue}{-0.5}, y, 0.918938533204673\right)\right) \]
  4. Applied rewrites100.0%

    \[\leadsto \color{blue}{\mathsf{fma}\left(y - 1, x, \mathsf{fma}\left(-0.5, y, 0.918938533204673\right)\right)} \]
  5. Add Preprocessing

Alternative 2: 97.9% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(y, x, -0.5 \cdot y\right)\\ \mathbf{if}\;y \leq -1.3:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y \leq 1.28:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (fma y x (* -0.5 y))))
   (if (<= y -1.3) t_0 (if (<= y 1.28) (- 0.918938533204673 x) t_0))))
double code(double x, double y) {
	double t_0 = fma(y, x, (-0.5 * y));
	double tmp;
	if (y <= -1.3) {
		tmp = t_0;
	} else if (y <= 1.28) {
		tmp = 0.918938533204673 - x;
	} else {
		tmp = t_0;
	}
	return tmp;
}
function code(x, y)
	t_0 = fma(y, x, Float64(-0.5 * y))
	tmp = 0.0
	if (y <= -1.3)
		tmp = t_0;
	elseif (y <= 1.28)
		tmp = Float64(0.918938533204673 - x);
	else
		tmp = t_0;
	end
	return tmp
end
code[x_, y_] := Block[{t$95$0 = N[(y * x + N[(-0.5 * y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -1.3], t$95$0, If[LessEqual[y, 1.28], N[(0.918938533204673 - x), $MachinePrecision], t$95$0]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(y, x, -0.5 \cdot y\right)\\
\mathbf{if}\;y \leq -1.3:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;y \leq 1.28:\\
\;\;\;\;0.918938533204673 - x\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -1.30000000000000004 or 1.28000000000000003 < y

    1. Initial program 100.0%

      \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
    2. Add Preprocessing
    3. Taylor expanded in y around inf

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

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

        \[\leadsto \color{blue}{\left(x + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)} \cdot y \]
      3. remove-double-negN/A

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

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

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

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

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

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

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

        \[\leadsto \left(\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right)\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right) \cdot y \]
      11. remove-double-negN/A

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

        \[\leadsto \color{blue}{\left(x - \frac{1}{2}\right)} \cdot y \]
      13. lower--.f6498.4

        \[\leadsto \color{blue}{\left(x - 0.5\right)} \cdot y \]
    5. Applied rewrites98.4%

      \[\leadsto \color{blue}{\left(x - 0.5\right) \cdot y} \]
    6. Step-by-step derivation
      1. Applied rewrites98.4%

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

      if -1.30000000000000004 < y < 1.28000000000000003

      1. Initial program 100.0%

        \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
      2. Add Preprocessing
      3. Taylor expanded in y around 0

        \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} + -1 \cdot x} \]
      4. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto \frac{918938533204673}{1000000000000000} + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)} \]
        2. unsub-negN/A

          \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - x} \]
        3. lower--.f6497.9

          \[\leadsto \color{blue}{0.918938533204673 - x} \]
      5. Applied rewrites97.9%

        \[\leadsto \color{blue}{0.918938533204673 - x} \]
    7. Recombined 2 regimes into one program.
    8. Add Preprocessing

    Alternative 3: 97.9% accurate, 1.0× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(x - 0.5\right) \cdot y\\ \mathbf{if}\;y \leq -1.3:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y \leq 1.28:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
    (FPCore (x y)
     :precision binary64
     (let* ((t_0 (* (- x 0.5) y)))
       (if (<= y -1.3) t_0 (if (<= y 1.28) (- 0.918938533204673 x) t_0))))
    double code(double x, double y) {
    	double t_0 = (x - 0.5) * y;
    	double tmp;
    	if (y <= -1.3) {
    		tmp = t_0;
    	} else if (y <= 1.28) {
    		tmp = 0.918938533204673 - x;
    	} else {
    		tmp = t_0;
    	}
    	return tmp;
    }
    
    real(8) function code(x, y)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        real(8) :: t_0
        real(8) :: tmp
        t_0 = (x - 0.5d0) * y
        if (y <= (-1.3d0)) then
            tmp = t_0
        else if (y <= 1.28d0) then
            tmp = 0.918938533204673d0 - x
        else
            tmp = t_0
        end if
        code = tmp
    end function
    
    public static double code(double x, double y) {
    	double t_0 = (x - 0.5) * y;
    	double tmp;
    	if (y <= -1.3) {
    		tmp = t_0;
    	} else if (y <= 1.28) {
    		tmp = 0.918938533204673 - x;
    	} else {
    		tmp = t_0;
    	}
    	return tmp;
    }
    
    def code(x, y):
    	t_0 = (x - 0.5) * y
    	tmp = 0
    	if y <= -1.3:
    		tmp = t_0
    	elif y <= 1.28:
    		tmp = 0.918938533204673 - x
    	else:
    		tmp = t_0
    	return tmp
    
    function code(x, y)
    	t_0 = Float64(Float64(x - 0.5) * y)
    	tmp = 0.0
    	if (y <= -1.3)
    		tmp = t_0;
    	elseif (y <= 1.28)
    		tmp = Float64(0.918938533204673 - x);
    	else
    		tmp = t_0;
    	end
    	return tmp
    end
    
    function tmp_2 = code(x, y)
    	t_0 = (x - 0.5) * y;
    	tmp = 0.0;
    	if (y <= -1.3)
    		tmp = t_0;
    	elseif (y <= 1.28)
    		tmp = 0.918938533204673 - x;
    	else
    		tmp = t_0;
    	end
    	tmp_2 = tmp;
    end
    
    code[x_, y_] := Block[{t$95$0 = N[(N[(x - 0.5), $MachinePrecision] * y), $MachinePrecision]}, If[LessEqual[y, -1.3], t$95$0, If[LessEqual[y, 1.28], N[(0.918938533204673 - x), $MachinePrecision], t$95$0]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := \left(x - 0.5\right) \cdot y\\
    \mathbf{if}\;y \leq -1.3:\\
    \;\;\;\;t\_0\\
    
    \mathbf{elif}\;y \leq 1.28:\\
    \;\;\;\;0.918938533204673 - x\\
    
    \mathbf{else}:\\
    \;\;\;\;t\_0\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if y < -1.30000000000000004 or 1.28000000000000003 < y

      1. Initial program 100.0%

        \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
      2. Add Preprocessing
      3. Taylor expanded in y around inf

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

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

          \[\leadsto \color{blue}{\left(x + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)} \cdot y \]
        3. remove-double-negN/A

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

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

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

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

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

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

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

          \[\leadsto \left(\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right)\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right) \cdot y \]
        11. remove-double-negN/A

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

          \[\leadsto \color{blue}{\left(x - \frac{1}{2}\right)} \cdot y \]
        13. lower--.f6498.4

          \[\leadsto \color{blue}{\left(x - 0.5\right)} \cdot y \]
      5. Applied rewrites98.4%

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

      if -1.30000000000000004 < y < 1.28000000000000003

      1. Initial program 100.0%

        \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
      2. Add Preprocessing
      3. Taylor expanded in y around 0

        \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} + -1 \cdot x} \]
      4. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto \frac{918938533204673}{1000000000000000} + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)} \]
        2. unsub-negN/A

          \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - x} \]
        3. lower--.f6497.9

          \[\leadsto \color{blue}{0.918938533204673 - x} \]
      5. Applied rewrites97.9%

        \[\leadsto \color{blue}{0.918938533204673 - x} \]
    3. Recombined 2 regimes into one program.
    4. Add Preprocessing

    Alternative 4: 74.7% accurate, 1.1× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -55:\\ \;\;\;\;x \cdot y\\ \mathbf{elif}\;y \leq 2 \cdot 10^{-14}:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(-0.5, y, 0.918938533204673\right)\\ \end{array} \end{array} \]
    (FPCore (x y)
     :precision binary64
     (if (<= y -55.0)
       (* x y)
       (if (<= y 2e-14) (- 0.918938533204673 x) (fma -0.5 y 0.918938533204673))))
    double code(double x, double y) {
    	double tmp;
    	if (y <= -55.0) {
    		tmp = x * y;
    	} else if (y <= 2e-14) {
    		tmp = 0.918938533204673 - x;
    	} else {
    		tmp = fma(-0.5, y, 0.918938533204673);
    	}
    	return tmp;
    }
    
    function code(x, y)
    	tmp = 0.0
    	if (y <= -55.0)
    		tmp = Float64(x * y);
    	elseif (y <= 2e-14)
    		tmp = Float64(0.918938533204673 - x);
    	else
    		tmp = fma(-0.5, y, 0.918938533204673);
    	end
    	return tmp
    end
    
    code[x_, y_] := If[LessEqual[y, -55.0], N[(x * y), $MachinePrecision], If[LessEqual[y, 2e-14], N[(0.918938533204673 - x), $MachinePrecision], N[(-0.5 * y + 0.918938533204673), $MachinePrecision]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;y \leq -55:\\
    \;\;\;\;x \cdot y\\
    
    \mathbf{elif}\;y \leq 2 \cdot 10^{-14}:\\
    \;\;\;\;0.918938533204673 - x\\
    
    \mathbf{else}:\\
    \;\;\;\;\mathsf{fma}\left(-0.5, y, 0.918938533204673\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if y < -55

      1. Initial program 100.0%

        \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
      2. Add Preprocessing
      3. Taylor expanded in x around inf

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

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

          \[\leadsto \color{blue}{\left(y - 1\right) \cdot x} \]
        3. lower--.f6457.4

          \[\leadsto \color{blue}{\left(y - 1\right)} \cdot x \]
      5. Applied rewrites57.4%

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

        \[\leadsto x \cdot \color{blue}{y} \]
      7. Step-by-step derivation
        1. Applied rewrites55.8%

          \[\leadsto y \cdot \color{blue}{x} \]

        if -55 < y < 2e-14

        1. Initial program 100.0%

          \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
        2. Add Preprocessing
        3. Taylor expanded in y around 0

          \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} + -1 \cdot x} \]
        4. Step-by-step derivation
          1. mul-1-negN/A

            \[\leadsto \frac{918938533204673}{1000000000000000} + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)} \]
          2. unsub-negN/A

            \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - x} \]
          3. lower--.f6499.3

            \[\leadsto \color{blue}{0.918938533204673 - x} \]
        5. Applied rewrites99.3%

          \[\leadsto \color{blue}{0.918938533204673 - x} \]

        if 2e-14 < y

        1. Initial program 99.9%

          \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - \frac{1}{2} \cdot y} \]
        4. Step-by-step derivation
          1. sub-negN/A

            \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} + \left(\mathsf{neg}\left(\frac{1}{2} \cdot y\right)\right)} \]
          2. +-commutativeN/A

            \[\leadsto \color{blue}{\left(\mathsf{neg}\left(\frac{1}{2} \cdot y\right)\right) + \frac{918938533204673}{1000000000000000}} \]
          3. distribute-lft-neg-inN/A

            \[\leadsto \color{blue}{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right) \cdot y} + \frac{918938533204673}{1000000000000000} \]
          4. metadata-evalN/A

            \[\leadsto \color{blue}{\frac{-1}{2}} \cdot y + \frac{918938533204673}{1000000000000000} \]
          5. lower-fma.f6462.3

            \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5, y, 0.918938533204673\right)} \]
        5. Applied rewrites62.3%

          \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5, y, 0.918938533204673\right)} \]
      8. Recombined 3 regimes into one program.
      9. Final simplification79.2%

        \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -55:\\ \;\;\;\;x \cdot y\\ \mathbf{elif}\;y \leq 2 \cdot 10^{-14}:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(-0.5, y, 0.918938533204673\right)\\ \end{array} \]
      10. Add Preprocessing

      Alternative 5: 74.5% accurate, 1.1× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -55:\\ \;\;\;\;x \cdot y\\ \mathbf{elif}\;y \leq 1.85:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot y\\ \end{array} \end{array} \]
      (FPCore (x y)
       :precision binary64
       (if (<= y -55.0) (* x y) (if (<= y 1.85) (- 0.918938533204673 x) (* -0.5 y))))
      double code(double x, double y) {
      	double tmp;
      	if (y <= -55.0) {
      		tmp = x * y;
      	} else if (y <= 1.85) {
      		tmp = 0.918938533204673 - x;
      	} else {
      		tmp = -0.5 * y;
      	}
      	return tmp;
      }
      
      real(8) function code(x, y)
          real(8), intent (in) :: x
          real(8), intent (in) :: y
          real(8) :: tmp
          if (y <= (-55.0d0)) then
              tmp = x * y
          else if (y <= 1.85d0) then
              tmp = 0.918938533204673d0 - x
          else
              tmp = (-0.5d0) * y
          end if
          code = tmp
      end function
      
      public static double code(double x, double y) {
      	double tmp;
      	if (y <= -55.0) {
      		tmp = x * y;
      	} else if (y <= 1.85) {
      		tmp = 0.918938533204673 - x;
      	} else {
      		tmp = -0.5 * y;
      	}
      	return tmp;
      }
      
      def code(x, y):
      	tmp = 0
      	if y <= -55.0:
      		tmp = x * y
      	elif y <= 1.85:
      		tmp = 0.918938533204673 - x
      	else:
      		tmp = -0.5 * y
      	return tmp
      
      function code(x, y)
      	tmp = 0.0
      	if (y <= -55.0)
      		tmp = Float64(x * y);
      	elseif (y <= 1.85)
      		tmp = Float64(0.918938533204673 - x);
      	else
      		tmp = Float64(-0.5 * y);
      	end
      	return tmp
      end
      
      function tmp_2 = code(x, y)
      	tmp = 0.0;
      	if (y <= -55.0)
      		tmp = x * y;
      	elseif (y <= 1.85)
      		tmp = 0.918938533204673 - x;
      	else
      		tmp = -0.5 * y;
      	end
      	tmp_2 = tmp;
      end
      
      code[x_, y_] := If[LessEqual[y, -55.0], N[(x * y), $MachinePrecision], If[LessEqual[y, 1.85], N[(0.918938533204673 - x), $MachinePrecision], N[(-0.5 * y), $MachinePrecision]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;y \leq -55:\\
      \;\;\;\;x \cdot y\\
      
      \mathbf{elif}\;y \leq 1.85:\\
      \;\;\;\;0.918938533204673 - x\\
      
      \mathbf{else}:\\
      \;\;\;\;-0.5 \cdot y\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if y < -55

        1. Initial program 100.0%

          \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
        2. Add Preprocessing
        3. Taylor expanded in x around inf

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

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

            \[\leadsto \color{blue}{\left(y - 1\right) \cdot x} \]
          3. lower--.f6457.4

            \[\leadsto \color{blue}{\left(y - 1\right)} \cdot x \]
        5. Applied rewrites57.4%

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

          \[\leadsto x \cdot \color{blue}{y} \]
        7. Step-by-step derivation
          1. Applied rewrites55.8%

            \[\leadsto y \cdot \color{blue}{x} \]

          if -55 < y < 1.8500000000000001

          1. Initial program 100.0%

            \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
          2. Add Preprocessing
          3. Taylor expanded in y around 0

            \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} + -1 \cdot x} \]
          4. Step-by-step derivation
            1. mul-1-negN/A

              \[\leadsto \frac{918938533204673}{1000000000000000} + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)} \]
            2. unsub-negN/A

              \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - x} \]
            3. lower--.f6497.9

              \[\leadsto \color{blue}{0.918938533204673 - x} \]
          5. Applied rewrites97.9%

            \[\leadsto \color{blue}{0.918938533204673 - x} \]

          if 1.8500000000000001 < y

          1. Initial program 99.9%

            \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
          2. Add Preprocessing
          3. Taylor expanded in y around inf

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

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

              \[\leadsto \color{blue}{\left(x + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)} \cdot y \]
            3. remove-double-negN/A

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

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

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

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

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

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

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

              \[\leadsto \left(\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right)\right) + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right) \cdot y \]
            11. remove-double-negN/A

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

              \[\leadsto \color{blue}{\left(x - \frac{1}{2}\right)} \cdot y \]
            13. lower--.f6498.9

              \[\leadsto \color{blue}{\left(x - 0.5\right)} \cdot y \]
          5. Applied rewrites98.9%

            \[\leadsto \color{blue}{\left(x - 0.5\right) \cdot y} \]
          6. Taylor expanded in x around 0

            \[\leadsto \frac{-1}{2} \cdot y \]
          7. Step-by-step derivation
            1. Applied rewrites60.3%

              \[\leadsto -0.5 \cdot y \]
          8. Recombined 3 regimes into one program.
          9. Final simplification78.8%

            \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -55:\\ \;\;\;\;x \cdot y\\ \mathbf{elif}\;y \leq 1.85:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot y\\ \end{array} \]
          10. Add Preprocessing

          Alternative 6: 73.5% accurate, 1.1× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -55:\\ \;\;\;\;x \cdot y\\ \mathbf{elif}\;y \leq 1.28:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{else}:\\ \;\;\;\;x \cdot y\\ \end{array} \end{array} \]
          (FPCore (x y)
           :precision binary64
           (if (<= y -55.0) (* x y) (if (<= y 1.28) (- 0.918938533204673 x) (* x y))))
          double code(double x, double y) {
          	double tmp;
          	if (y <= -55.0) {
          		tmp = x * y;
          	} else if (y <= 1.28) {
          		tmp = 0.918938533204673 - x;
          	} else {
          		tmp = x * y;
          	}
          	return tmp;
          }
          
          real(8) function code(x, y)
              real(8), intent (in) :: x
              real(8), intent (in) :: y
              real(8) :: tmp
              if (y <= (-55.0d0)) then
                  tmp = x * y
              else if (y <= 1.28d0) then
                  tmp = 0.918938533204673d0 - x
              else
                  tmp = x * y
              end if
              code = tmp
          end function
          
          public static double code(double x, double y) {
          	double tmp;
          	if (y <= -55.0) {
          		tmp = x * y;
          	} else if (y <= 1.28) {
          		tmp = 0.918938533204673 - x;
          	} else {
          		tmp = x * y;
          	}
          	return tmp;
          }
          
          def code(x, y):
          	tmp = 0
          	if y <= -55.0:
          		tmp = x * y
          	elif y <= 1.28:
          		tmp = 0.918938533204673 - x
          	else:
          		tmp = x * y
          	return tmp
          
          function code(x, y)
          	tmp = 0.0
          	if (y <= -55.0)
          		tmp = Float64(x * y);
          	elseif (y <= 1.28)
          		tmp = Float64(0.918938533204673 - x);
          	else
          		tmp = Float64(x * y);
          	end
          	return tmp
          end
          
          function tmp_2 = code(x, y)
          	tmp = 0.0;
          	if (y <= -55.0)
          		tmp = x * y;
          	elseif (y <= 1.28)
          		tmp = 0.918938533204673 - x;
          	else
          		tmp = x * y;
          	end
          	tmp_2 = tmp;
          end
          
          code[x_, y_] := If[LessEqual[y, -55.0], N[(x * y), $MachinePrecision], If[LessEqual[y, 1.28], N[(0.918938533204673 - x), $MachinePrecision], N[(x * y), $MachinePrecision]]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;y \leq -55:\\
          \;\;\;\;x \cdot y\\
          
          \mathbf{elif}\;y \leq 1.28:\\
          \;\;\;\;0.918938533204673 - x\\
          
          \mathbf{else}:\\
          \;\;\;\;x \cdot y\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if y < -55 or 1.28000000000000003 < y

            1. Initial program 100.0%

              \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
            2. Add Preprocessing
            3. Taylor expanded in x around inf

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

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

                \[\leadsto \color{blue}{\left(y - 1\right) \cdot x} \]
              3. lower--.f6449.8

                \[\leadsto \color{blue}{\left(y - 1\right)} \cdot x \]
            5. Applied rewrites49.8%

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

              \[\leadsto x \cdot \color{blue}{y} \]
            7. Step-by-step derivation
              1. Applied rewrites48.8%

                \[\leadsto y \cdot \color{blue}{x} \]

              if -55 < y < 1.28000000000000003

              1. Initial program 100.0%

                \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
              2. Add Preprocessing
              3. Taylor expanded in y around 0

                \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} + -1 \cdot x} \]
              4. Step-by-step derivation
                1. mul-1-negN/A

                  \[\leadsto \frac{918938533204673}{1000000000000000} + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)} \]
                2. unsub-negN/A

                  \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - x} \]
                3. lower--.f6497.9

                  \[\leadsto \color{blue}{0.918938533204673 - x} \]
              5. Applied rewrites97.9%

                \[\leadsto \color{blue}{0.918938533204673 - x} \]
            8. Recombined 2 regimes into one program.
            9. Final simplification74.5%

              \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -55:\\ \;\;\;\;x \cdot y\\ \mathbf{elif}\;y \leq 1.28:\\ \;\;\;\;0.918938533204673 - x\\ \mathbf{else}:\\ \;\;\;\;x \cdot y\\ \end{array} \]
            10. Add Preprocessing

            Alternative 7: 49.6% accurate, 1.3× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -0.82:\\ \;\;\;\;-x\\ \mathbf{elif}\;x \leq 0.92:\\ \;\;\;\;0.918938533204673\\ \mathbf{else}:\\ \;\;\;\;-x\\ \end{array} \end{array} \]
            (FPCore (x y)
             :precision binary64
             (if (<= x -0.82) (- x) (if (<= x 0.92) 0.918938533204673 (- x))))
            double code(double x, double y) {
            	double tmp;
            	if (x <= -0.82) {
            		tmp = -x;
            	} else if (x <= 0.92) {
            		tmp = 0.918938533204673;
            	} else {
            		tmp = -x;
            	}
            	return tmp;
            }
            
            real(8) function code(x, y)
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                real(8) :: tmp
                if (x <= (-0.82d0)) then
                    tmp = -x
                else if (x <= 0.92d0) then
                    tmp = 0.918938533204673d0
                else
                    tmp = -x
                end if
                code = tmp
            end function
            
            public static double code(double x, double y) {
            	double tmp;
            	if (x <= -0.82) {
            		tmp = -x;
            	} else if (x <= 0.92) {
            		tmp = 0.918938533204673;
            	} else {
            		tmp = -x;
            	}
            	return tmp;
            }
            
            def code(x, y):
            	tmp = 0
            	if x <= -0.82:
            		tmp = -x
            	elif x <= 0.92:
            		tmp = 0.918938533204673
            	else:
            		tmp = -x
            	return tmp
            
            function code(x, y)
            	tmp = 0.0
            	if (x <= -0.82)
            		tmp = Float64(-x);
            	elseif (x <= 0.92)
            		tmp = 0.918938533204673;
            	else
            		tmp = Float64(-x);
            	end
            	return tmp
            end
            
            function tmp_2 = code(x, y)
            	tmp = 0.0;
            	if (x <= -0.82)
            		tmp = -x;
            	elseif (x <= 0.92)
            		tmp = 0.918938533204673;
            	else
            		tmp = -x;
            	end
            	tmp_2 = tmp;
            end
            
            code[x_, y_] := If[LessEqual[x, -0.82], (-x), If[LessEqual[x, 0.92], 0.918938533204673, (-x)]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;x \leq -0.82:\\
            \;\;\;\;-x\\
            
            \mathbf{elif}\;x \leq 0.92:\\
            \;\;\;\;0.918938533204673\\
            
            \mathbf{else}:\\
            \;\;\;\;-x\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if x < -0.819999999999999951 or 0.92000000000000004 < x

              1. Initial program 100.0%

                \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
              2. Add Preprocessing
              3. Taylor expanded in y around 0

                \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} + -1 \cdot x} \]
              4. Step-by-step derivation
                1. mul-1-negN/A

                  \[\leadsto \frac{918938533204673}{1000000000000000} + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)} \]
                2. unsub-negN/A

                  \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - x} \]
                3. lower--.f6455.9

                  \[\leadsto \color{blue}{0.918938533204673 - x} \]
              5. Applied rewrites55.9%

                \[\leadsto \color{blue}{0.918938533204673 - x} \]
              6. Taylor expanded in x around inf

                \[\leadsto -1 \cdot \color{blue}{x} \]
              7. Step-by-step derivation
                1. Applied rewrites53.5%

                  \[\leadsto -x \]

                if -0.819999999999999951 < x < 0.92000000000000004

                1. Initial program 100.0%

                  \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
                2. Add Preprocessing
                3. Taylor expanded in y around 0

                  \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} + -1 \cdot x} \]
                4. Step-by-step derivation
                  1. mul-1-negN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)} \]
                  2. unsub-negN/A

                    \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - x} \]
                  3. lower--.f6450.0

                    \[\leadsto \color{blue}{0.918938533204673 - x} \]
                5. Applied rewrites50.0%

                  \[\leadsto \color{blue}{0.918938533204673 - x} \]
                6. Taylor expanded in x around 0

                  \[\leadsto \frac{918938533204673}{1000000000000000} \]
                7. Step-by-step derivation
                  1. Applied rewrites47.5%

                    \[\leadsto 0.918938533204673 \]
                8. Recombined 2 regimes into one program.
                9. Add Preprocessing

                Alternative 8: 100.0% accurate, 1.5× speedup?

                \[\begin{array}{l} \\ 0.918938533204673 - \mathsf{fma}\left(0.5 - x, y, x\right) \end{array} \]
                (FPCore (x y) :precision binary64 (- 0.918938533204673 (fma (- 0.5 x) y x)))
                double code(double x, double y) {
                	return 0.918938533204673 - fma((0.5 - x), y, x);
                }
                
                function code(x, y)
                	return Float64(0.918938533204673 - fma(Float64(0.5 - x), y, x))
                end
                
                code[x_, y_] := N[(0.918938533204673 - N[(N[(0.5 - x), $MachinePrecision] * y + x), $MachinePrecision]), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                0.918938533204673 - \mathsf{fma}\left(0.5 - x, y, x\right)
                \end{array}
                
                Derivation
                1. Initial program 100.0%

                  \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
                2. Add Preprocessing
                3. Taylor expanded in y around 0

                  \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} + \left(-1 \cdot x + y \cdot \left(x - \frac{1}{2}\right)\right)} \]
                4. Step-by-step derivation
                  1. associate-+r+N/A

                    \[\leadsto \color{blue}{\left(\frac{918938533204673}{1000000000000000} + -1 \cdot x\right) + y \cdot \left(x - \frac{1}{2}\right)} \]
                  2. mul-1-negN/A

                    \[\leadsto \left(\frac{918938533204673}{1000000000000000} + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right) + y \cdot \left(x - \frac{1}{2}\right) \]
                  3. unsub-negN/A

                    \[\leadsto \color{blue}{\left(\frac{918938533204673}{1000000000000000} - x\right)} + y \cdot \left(x - \frac{1}{2}\right) \]
                  4. associate-+l-N/A

                    \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - \left(x - y \cdot \left(x - \frac{1}{2}\right)\right)} \]
                  5. *-commutativeN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(x - \color{blue}{\left(x - \frac{1}{2}\right) \cdot y}\right) \]
                  6. cancel-sign-sub-invN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \color{blue}{\left(x + \left(\mathsf{neg}\left(\left(x - \frac{1}{2}\right)\right)\right) \cdot y\right)} \]
                  7. *-rgt-identityN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(\color{blue}{x \cdot 1} + \left(\mathsf{neg}\left(\left(x - \frac{1}{2}\right)\right)\right) \cdot y\right) \]
                  8. rgt-mult-inverseN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(x \cdot \color{blue}{\left(y \cdot \frac{1}{y}\right)} + \left(\mathsf{neg}\left(\left(x - \frac{1}{2}\right)\right)\right) \cdot y\right) \]
                  9. associate-*r/N/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(x \cdot \color{blue}{\frac{y \cdot 1}{y}} + \left(\mathsf{neg}\left(\left(x - \frac{1}{2}\right)\right)\right) \cdot y\right) \]
                  10. *-rgt-identityN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(x \cdot \frac{\color{blue}{y}}{y} + \left(\mathsf{neg}\left(\left(x - \frac{1}{2}\right)\right)\right) \cdot y\right) \]
                  11. associate-/l*N/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(\color{blue}{\frac{x \cdot y}{y}} + \left(\mathsf{neg}\left(\left(x - \frac{1}{2}\right)\right)\right) \cdot y\right) \]
                  12. associate-*l/N/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(\color{blue}{\frac{x}{y} \cdot y} + \left(\mathsf{neg}\left(\left(x - \frac{1}{2}\right)\right)\right) \cdot y\right) \]
                  13. sub0-negN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(\frac{x}{y} \cdot y + \color{blue}{\left(0 - \left(x - \frac{1}{2}\right)\right)} \cdot y\right) \]
                  14. associate-+l-N/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(\frac{x}{y} \cdot y + \color{blue}{\left(\left(0 - x\right) + \frac{1}{2}\right)} \cdot y\right) \]
                  15. neg-sub0N/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(\frac{x}{y} \cdot y + \left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)} + \frac{1}{2}\right) \cdot y\right) \]
                  16. mul-1-negN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(\frac{x}{y} \cdot y + \left(\color{blue}{-1 \cdot x} + \frac{1}{2}\right) \cdot y\right) \]
                  17. +-commutativeN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \left(\frac{x}{y} \cdot y + \color{blue}{\left(\frac{1}{2} + -1 \cdot x\right)} \cdot y\right) \]
                  18. distribute-rgt-inN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - \color{blue}{y \cdot \left(\frac{x}{y} + \left(\frac{1}{2} + -1 \cdot x\right)\right)} \]
                  19. +-commutativeN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - y \cdot \color{blue}{\left(\left(\frac{1}{2} + -1 \cdot x\right) + \frac{x}{y}\right)} \]
                  20. associate-+r+N/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} - y \cdot \color{blue}{\left(\frac{1}{2} + \left(-1 \cdot x + \frac{x}{y}\right)\right)} \]
                  21. lower--.f64N/A

                    \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - y \cdot \left(\frac{1}{2} + \left(-1 \cdot x + \frac{x}{y}\right)\right)} \]
                5. Applied rewrites100.0%

                  \[\leadsto \color{blue}{0.918938533204673 - \mathsf{fma}\left(0.5 - x, y, x\right)} \]
                6. Add Preprocessing

                Alternative 9: 50.6% accurate, 5.0× speedup?

                \[\begin{array}{l} \\ 0.918938533204673 - x \end{array} \]
                (FPCore (x y) :precision binary64 (- 0.918938533204673 x))
                double code(double x, double y) {
                	return 0.918938533204673 - x;
                }
                
                real(8) function code(x, y)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    code = 0.918938533204673d0 - x
                end function
                
                public static double code(double x, double y) {
                	return 0.918938533204673 - x;
                }
                
                def code(x, y):
                	return 0.918938533204673 - x
                
                function code(x, y)
                	return Float64(0.918938533204673 - x)
                end
                
                function tmp = code(x, y)
                	tmp = 0.918938533204673 - x;
                end
                
                code[x_, y_] := N[(0.918938533204673 - x), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                0.918938533204673 - x
                \end{array}
                
                Derivation
                1. Initial program 100.0%

                  \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
                2. Add Preprocessing
                3. Taylor expanded in y around 0

                  \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} + -1 \cdot x} \]
                4. Step-by-step derivation
                  1. mul-1-negN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)} \]
                  2. unsub-negN/A

                    \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - x} \]
                  3. lower--.f6453.0

                    \[\leadsto \color{blue}{0.918938533204673 - x} \]
                5. Applied rewrites53.0%

                  \[\leadsto \color{blue}{0.918938533204673 - x} \]
                6. Add Preprocessing

                Alternative 10: 25.9% accurate, 20.0× speedup?

                \[\begin{array}{l} \\ 0.918938533204673 \end{array} \]
                (FPCore (x y) :precision binary64 0.918938533204673)
                double code(double x, double y) {
                	return 0.918938533204673;
                }
                
                real(8) function code(x, y)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    code = 0.918938533204673d0
                end function
                
                public static double code(double x, double y) {
                	return 0.918938533204673;
                }
                
                def code(x, y):
                	return 0.918938533204673
                
                function code(x, y)
                	return 0.918938533204673
                end
                
                function tmp = code(x, y)
                	tmp = 0.918938533204673;
                end
                
                code[x_, y_] := 0.918938533204673
                
                \begin{array}{l}
                
                \\
                0.918938533204673
                \end{array}
                
                Derivation
                1. Initial program 100.0%

                  \[\left(x \cdot \left(y - 1\right) - y \cdot 0.5\right) + 0.918938533204673 \]
                2. Add Preprocessing
                3. Taylor expanded in y around 0

                  \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} + -1 \cdot x} \]
                4. Step-by-step derivation
                  1. mul-1-negN/A

                    \[\leadsto \frac{918938533204673}{1000000000000000} + \color{blue}{\left(\mathsf{neg}\left(x\right)\right)} \]
                  2. unsub-negN/A

                    \[\leadsto \color{blue}{\frac{918938533204673}{1000000000000000} - x} \]
                  3. lower--.f6453.0

                    \[\leadsto \color{blue}{0.918938533204673 - x} \]
                5. Applied rewrites53.0%

                  \[\leadsto \color{blue}{0.918938533204673 - x} \]
                6. Taylor expanded in x around 0

                  \[\leadsto \frac{918938533204673}{1000000000000000} \]
                7. Step-by-step derivation
                  1. Applied rewrites24.5%

                    \[\leadsto 0.918938533204673 \]
                  2. Add Preprocessing

                  Reproduce

                  ?
                  herbie shell --seed 2024244 
                  (FPCore (x y)
                    :name "Numeric.SpecFunctions:logGamma from math-functions-0.1.5.2, A"
                    :precision binary64
                    (+ (- (* x (- y 1.0)) (* y 0.5)) 0.918938533204673))