Numeric.SpecFunctions:invIncompleteGamma from math-functions-0.1.5.2, B

Percentage Accurate: 72.4% → 99.9%
Time: 11.4s
Alternatives: 14
Speedup: 1.1×

Specification

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

\\
1 - \log \left(1 - \frac{x - y}{1 - y}\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 14 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: 72.4% accurate, 1.0× speedup?

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

\\
1 - \log \left(1 - \frac{x - y}{1 - y}\right)
\end{array}

Alternative 1: 99.9% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{\left(x + -1\right) + \frac{-1 + \left(x + \frac{x + -1}{y}\right)}{y}}{y}\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= (/ (- x y) (- 1.0 y)) 0.5)
   (- 1.0 (log1p (/ (- x y) (+ y -1.0))))
   (- 1.0 (log (/ (+ (+ x -1.0) (/ (+ -1.0 (+ x (/ (+ x -1.0) y))) y)) y)))))
double code(double x, double y) {
	double tmp;
	if (((x - y) / (1.0 - y)) <= 0.5) {
		tmp = 1.0 - log1p(((x - y) / (y + -1.0)));
	} else {
		tmp = 1.0 - log((((x + -1.0) + ((-1.0 + (x + ((x + -1.0) / y))) / y)) / y));
	}
	return tmp;
}
public static double code(double x, double y) {
	double tmp;
	if (((x - y) / (1.0 - y)) <= 0.5) {
		tmp = 1.0 - Math.log1p(((x - y) / (y + -1.0)));
	} else {
		tmp = 1.0 - Math.log((((x + -1.0) + ((-1.0 + (x + ((x + -1.0) / y))) / y)) / y));
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if ((x - y) / (1.0 - y)) <= 0.5:
		tmp = 1.0 - math.log1p(((x - y) / (y + -1.0)))
	else:
		tmp = 1.0 - math.log((((x + -1.0) + ((-1.0 + (x + ((x + -1.0) / y))) / y)) / y))
	return tmp
function code(x, y)
	tmp = 0.0
	if (Float64(Float64(x - y) / Float64(1.0 - y)) <= 0.5)
		tmp = Float64(1.0 - log1p(Float64(Float64(x - y) / Float64(y + -1.0))));
	else
		tmp = Float64(1.0 - log(Float64(Float64(Float64(x + -1.0) + Float64(Float64(-1.0 + Float64(x + Float64(Float64(x + -1.0) / y))) / y)) / y)));
	end
	return tmp
end
code[x_, y_] := If[LessEqual[N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision], 0.5], N[(1.0 - N[Log[1 + N[(N[(x - y), $MachinePrecision] / N[(y + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(N[(N[(x + -1.0), $MachinePrecision] + N[(N[(-1.0 + N[(x + N[(N[(x + -1.0), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\
\;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\

\mathbf{else}:\\
\;\;\;\;1 - \log \left(\frac{\left(x + -1\right) + \frac{-1 + \left(x + \frac{x + -1}{y}\right)}{y}}{y}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.5

    1. Initial program 99.9%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto 1 - \log \color{blue}{\left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)} \]
      2. accelerator-lowering-log1p.f64N/A

        \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)} \]
      3. distribute-neg-frac2N/A

        \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}}\right) \]
      4. /-lowering-/.f64N/A

        \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}}\right) \]
      5. --lowering--.f64N/A

        \[\leadsto 1 - \mathsf{log1p}\left(\frac{\color{blue}{x - y}}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right) \]
      6. sub-negN/A

        \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\mathsf{neg}\left(\color{blue}{\left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)}\right)}\right) \]
      7. +-commutativeN/A

        \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\mathsf{neg}\left(\color{blue}{\left(\left(\mathsf{neg}\left(y\right)\right) + 1\right)}\right)}\right) \]
      8. distribute-neg-inN/A

        \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(y\right)\right)\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}}\right) \]
      9. remove-double-negN/A

        \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\color{blue}{y} + \left(\mathsf{neg}\left(1\right)\right)}\right) \]
      10. metadata-evalN/A

        \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{y + \color{blue}{-1}}\right) \]
      11. +-lowering-+.f64100.0

        \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\color{blue}{y + -1}}\right) \]
    4. Applied egg-rr100.0%

      \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]

    if 0.5 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

    1. Initial program 8.3%

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

      \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{\left(1 + -1 \cdot \frac{\left(x + -1 \cdot \frac{1 + -1 \cdot x}{y}\right) - 1}{y}\right) - x}{y}\right)} \]
    4. Simplified100.0%

      \[\leadsto 1 - \log \color{blue}{\left(\frac{\frac{-1 + \left(x + \frac{-1 + x}{y}\right)}{y} + \left(-1 + x\right)}{y}\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification100.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{\left(x + -1\right) + \frac{-1 + \left(x + \frac{x + -1}{y}\right)}{y}}{y}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 99.0% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{x - y}{1 - y}\\ \mathbf{if}\;t\_0 \leq -1000000:\\ \;\;\;\;1 - \log \left(\frac{x}{y + -1}\right)\\ \mathbf{elif}\;t\_0 \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(y, \mathsf{fma}\left(y, -0.5, -1\right), 1\right) - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x + -1}\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (/ (- x y) (- 1.0 y))))
   (if (<= t_0 -1000000.0)
     (- 1.0 (log (/ x (+ y -1.0))))
     (if (<= t_0 0.5)
       (- (fma y (fma y -0.5 -1.0) 1.0) (log1p (- x)))
       (+ 1.0 (log (/ y (+ x -1.0))))))))
double code(double x, double y) {
	double t_0 = (x - y) / (1.0 - y);
	double tmp;
	if (t_0 <= -1000000.0) {
		tmp = 1.0 - log((x / (y + -1.0)));
	} else if (t_0 <= 0.5) {
		tmp = fma(y, fma(y, -0.5, -1.0), 1.0) - log1p(-x);
	} else {
		tmp = 1.0 + log((y / (x + -1.0)));
	}
	return tmp;
}
function code(x, y)
	t_0 = Float64(Float64(x - y) / Float64(1.0 - y))
	tmp = 0.0
	if (t_0 <= -1000000.0)
		tmp = Float64(1.0 - log(Float64(x / Float64(y + -1.0))));
	elseif (t_0 <= 0.5)
		tmp = Float64(fma(y, fma(y, -0.5, -1.0), 1.0) - log1p(Float64(-x)));
	else
		tmp = Float64(1.0 + log(Float64(y / Float64(x + -1.0))));
	end
	return tmp
end
code[x_, y_] := Block[{t$95$0 = N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -1000000.0], N[(1.0 - N[Log[N[(x / N[(y + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 0.5], N[(N[(y * N[(y * -0.5 + -1.0), $MachinePrecision] + 1.0), $MachinePrecision] - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision], N[(1.0 + N[Log[N[(y / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{x - y}{1 - y}\\
\mathbf{if}\;t\_0 \leq -1000000:\\
\;\;\;\;1 - \log \left(\frac{x}{y + -1}\right)\\

\mathbf{elif}\;t\_0 \leq 0.5:\\
\;\;\;\;\mathsf{fma}\left(y, \mathsf{fma}\left(y, -0.5, -1\right), 1\right) - \mathsf{log1p}\left(-x\right)\\

\mathbf{else}:\\
\;\;\;\;1 + \log \left(\frac{y}{x + -1}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < -1e6

    1. Initial program 100.0%

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

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

        \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{x}{1 - y}\right)\right)} \]
      2. distribute-neg-frac2N/A

        \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)} \]
      3. /-lowering-/.f64N/A

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

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

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

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

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

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

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

        \[\leadsto 1 - \log \left(\frac{x}{y + \color{blue}{-1}}\right) \]
      11. +-lowering-+.f6499.6

        \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{y + -1}}\right) \]
    5. Simplified99.6%

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

    if -1e6 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.5

    1. Initial program 99.9%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around 0

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

        \[\leadsto \color{blue}{\left(1 + y \cdot \left(\frac{-1}{2} \cdot \left(y \cdot \left(-1 \cdot \frac{{\left(1 + -1 \cdot x\right)}^{2}}{{\left(1 - x\right)}^{2}} + 2 \cdot \frac{1 + -1 \cdot x}{1 - x}\right)\right) - \left(-1 \cdot \frac{x}{1 - x} + \frac{1}{1 - x}\right)\right)\right) - \log \left(1 - x\right)} \]
    5. Simplified97.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(y, \mathsf{fma}\left(y, -0.5, -1\right), 1\right) - \mathsf{log1p}\left(-x\right)} \]

    if 0.5 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

    1. Initial program 8.3%

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

      \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

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

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

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

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

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

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

        \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
      8. /-lowering-/.f64N/A

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

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

        \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
      11. +-commutativeN/A

        \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
      12. +-lowering-+.f6499.2

        \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
    5. Simplified99.2%

      \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + x}{y}\right)} \]
    6. Step-by-step derivation
      1. sub-negN/A

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

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

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

        \[\leadsto \color{blue}{\log \left(\frac{1}{\frac{-1 + x}{y}}\right)} + 1 \]
      5. clear-numN/A

        \[\leadsto \log \color{blue}{\left(\frac{y}{-1 + x}\right)} + 1 \]
      6. log-lowering-log.f64N/A

        \[\leadsto \color{blue}{\log \left(\frac{y}{-1 + x}\right)} + 1 \]
      7. /-lowering-/.f64N/A

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

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

        \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
    7. Applied egg-rr99.2%

      \[\leadsto \color{blue}{\log \left(\frac{y}{x + -1}\right) + 1} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification98.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq -1000000:\\ \;\;\;\;1 - \log \left(\frac{x}{y + -1}\right)\\ \mathbf{elif}\;\frac{x - y}{1 - y} \leq 0.5:\\ \;\;\;\;\mathsf{fma}\left(y, \mathsf{fma}\left(y, -0.5, -1\right), 1\right) - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x + -1}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 98.8% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{x - y}{1 - y}\\ \mathbf{if}\;t\_0 \leq -1000000:\\ \;\;\;\;1 - \log \left(\frac{x}{y + -1}\right)\\ \mathbf{elif}\;t\_0 \leq 0.5:\\ \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x + -1}\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (/ (- x y) (- 1.0 y))))
   (if (<= t_0 -1000000.0)
     (- 1.0 (log (/ x (+ y -1.0))))
     (if (<= t_0 0.5)
       (- (- 1.0 y) (log1p (- x)))
       (+ 1.0 (log (/ y (+ x -1.0))))))))
double code(double x, double y) {
	double t_0 = (x - y) / (1.0 - y);
	double tmp;
	if (t_0 <= -1000000.0) {
		tmp = 1.0 - log((x / (y + -1.0)));
	} else if (t_0 <= 0.5) {
		tmp = (1.0 - y) - log1p(-x);
	} else {
		tmp = 1.0 + log((y / (x + -1.0)));
	}
	return tmp;
}
public static double code(double x, double y) {
	double t_0 = (x - y) / (1.0 - y);
	double tmp;
	if (t_0 <= -1000000.0) {
		tmp = 1.0 - Math.log((x / (y + -1.0)));
	} else if (t_0 <= 0.5) {
		tmp = (1.0 - y) - Math.log1p(-x);
	} else {
		tmp = 1.0 + Math.log((y / (x + -1.0)));
	}
	return tmp;
}
def code(x, y):
	t_0 = (x - y) / (1.0 - y)
	tmp = 0
	if t_0 <= -1000000.0:
		tmp = 1.0 - math.log((x / (y + -1.0)))
	elif t_0 <= 0.5:
		tmp = (1.0 - y) - math.log1p(-x)
	else:
		tmp = 1.0 + math.log((y / (x + -1.0)))
	return tmp
function code(x, y)
	t_0 = Float64(Float64(x - y) / Float64(1.0 - y))
	tmp = 0.0
	if (t_0 <= -1000000.0)
		tmp = Float64(1.0 - log(Float64(x / Float64(y + -1.0))));
	elseif (t_0 <= 0.5)
		tmp = Float64(Float64(1.0 - y) - log1p(Float64(-x)));
	else
		tmp = Float64(1.0 + log(Float64(y / Float64(x + -1.0))));
	end
	return tmp
end
code[x_, y_] := Block[{t$95$0 = N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -1000000.0], N[(1.0 - N[Log[N[(x / N[(y + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 0.5], N[(N[(1.0 - y), $MachinePrecision] - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision], N[(1.0 + N[Log[N[(y / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{x - y}{1 - y}\\
\mathbf{if}\;t\_0 \leq -1000000:\\
\;\;\;\;1 - \log \left(\frac{x}{y + -1}\right)\\

\mathbf{elif}\;t\_0 \leq 0.5:\\
\;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\

\mathbf{else}:\\
\;\;\;\;1 + \log \left(\frac{y}{x + -1}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < -1e6

    1. Initial program 100.0%

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

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

        \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{x}{1 - y}\right)\right)} \]
      2. distribute-neg-frac2N/A

        \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)} \]
      3. /-lowering-/.f64N/A

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

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

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

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

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

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

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

        \[\leadsto 1 - \log \left(\frac{x}{y + \color{blue}{-1}}\right) \]
      11. +-lowering-+.f6499.6

        \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{y + -1}}\right) \]
    5. Simplified99.6%

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

    if -1e6 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.5

    1. Initial program 99.9%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around 0

      \[\leadsto \color{blue}{\left(1 + -1 \cdot \left(y \cdot \left(-1 \cdot \frac{x}{1 - x} + \frac{1}{1 - x}\right)\right)\right) - \log \left(1 - x\right)} \]
    4. Step-by-step derivation
      1. Simplified97.5%

        \[\leadsto \color{blue}{\left(1 - y\right) - \mathsf{log1p}\left(-x\right)} \]

      if 0.5 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

      1. Initial program 8.3%

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

        \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
      4. Step-by-step derivation
        1. mul-1-negN/A

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

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

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

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

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

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

          \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
        8. /-lowering-/.f64N/A

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

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

          \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
        11. +-commutativeN/A

          \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
        12. +-lowering-+.f6499.2

          \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
      5. Simplified99.2%

        \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + x}{y}\right)} \]
      6. Step-by-step derivation
        1. sub-negN/A

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

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

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

          \[\leadsto \color{blue}{\log \left(\frac{1}{\frac{-1 + x}{y}}\right)} + 1 \]
        5. clear-numN/A

          \[\leadsto \log \color{blue}{\left(\frac{y}{-1 + x}\right)} + 1 \]
        6. log-lowering-log.f64N/A

          \[\leadsto \color{blue}{\log \left(\frac{y}{-1 + x}\right)} + 1 \]
        7. /-lowering-/.f64N/A

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

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

          \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
      7. Applied egg-rr99.2%

        \[\leadsto \color{blue}{\log \left(\frac{y}{x + -1}\right) + 1} \]
    5. Recombined 3 regimes into one program.
    6. Final simplification98.6%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq -1000000:\\ \;\;\;\;1 - \log \left(\frac{x}{y + -1}\right)\\ \mathbf{elif}\;\frac{x - y}{1 - y} \leq 0.5:\\ \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x + -1}\right)\\ \end{array} \]
    7. Add Preprocessing

    Alternative 4: 99.8% accurate, 0.8× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{-1 + \left(x + \frac{x + -1}{y}\right)}{y}\right)\\ \end{array} \end{array} \]
    (FPCore (x y)
     :precision binary64
     (if (<= (/ (- x y) (- 1.0 y)) 0.5)
       (- 1.0 (log1p (/ (- x y) (+ y -1.0))))
       (- 1.0 (log (/ (+ -1.0 (+ x (/ (+ x -1.0) y))) y)))))
    double code(double x, double y) {
    	double tmp;
    	if (((x - y) / (1.0 - y)) <= 0.5) {
    		tmp = 1.0 - log1p(((x - y) / (y + -1.0)));
    	} else {
    		tmp = 1.0 - log(((-1.0 + (x + ((x + -1.0) / y))) / y));
    	}
    	return tmp;
    }
    
    public static double code(double x, double y) {
    	double tmp;
    	if (((x - y) / (1.0 - y)) <= 0.5) {
    		tmp = 1.0 - Math.log1p(((x - y) / (y + -1.0)));
    	} else {
    		tmp = 1.0 - Math.log(((-1.0 + (x + ((x + -1.0) / y))) / y));
    	}
    	return tmp;
    }
    
    def code(x, y):
    	tmp = 0
    	if ((x - y) / (1.0 - y)) <= 0.5:
    		tmp = 1.0 - math.log1p(((x - y) / (y + -1.0)))
    	else:
    		tmp = 1.0 - math.log(((-1.0 + (x + ((x + -1.0) / y))) / y))
    	return tmp
    
    function code(x, y)
    	tmp = 0.0
    	if (Float64(Float64(x - y) / Float64(1.0 - y)) <= 0.5)
    		tmp = Float64(1.0 - log1p(Float64(Float64(x - y) / Float64(y + -1.0))));
    	else
    		tmp = Float64(1.0 - log(Float64(Float64(-1.0 + Float64(x + Float64(Float64(x + -1.0) / y))) / y)));
    	end
    	return tmp
    end
    
    code[x_, y_] := If[LessEqual[N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision], 0.5], N[(1.0 - N[Log[1 + N[(N[(x - y), $MachinePrecision] / N[(y + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(N[(-1.0 + N[(x + N[(N[(x + -1.0), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\
    \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;1 - \log \left(\frac{-1 + \left(x + \frac{x + -1}{y}\right)}{y}\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.5

      1. Initial program 99.9%

        \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. sub-negN/A

          \[\leadsto 1 - \log \color{blue}{\left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)} \]
        2. accelerator-lowering-log1p.f64N/A

          \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)} \]
        3. distribute-neg-frac2N/A

          \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}}\right) \]
        4. /-lowering-/.f64N/A

          \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}}\right) \]
        5. --lowering--.f64N/A

          \[\leadsto 1 - \mathsf{log1p}\left(\frac{\color{blue}{x - y}}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right) \]
        6. sub-negN/A

          \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\mathsf{neg}\left(\color{blue}{\left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)}\right)}\right) \]
        7. +-commutativeN/A

          \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\mathsf{neg}\left(\color{blue}{\left(\left(\mathsf{neg}\left(y\right)\right) + 1\right)}\right)}\right) \]
        8. distribute-neg-inN/A

          \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(y\right)\right)\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}}\right) \]
        9. remove-double-negN/A

          \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\color{blue}{y} + \left(\mathsf{neg}\left(1\right)\right)}\right) \]
        10. metadata-evalN/A

          \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{y + \color{blue}{-1}}\right) \]
        11. +-lowering-+.f64100.0

          \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\color{blue}{y + -1}}\right) \]
      4. Applied egg-rr100.0%

        \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]

      if 0.5 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

      1. Initial program 8.3%

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

        \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{\left(1 + -1 \cdot \frac{x - 1}{y}\right) - x}{y}\right)} \]
      4. Step-by-step derivation
        1. sub-negN/A

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

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

          \[\leadsto 1 - \log \left(-1 \cdot \frac{\color{blue}{1 + \left(-1 \cdot \frac{x - 1}{y} + -1 \cdot x\right)}}{y}\right) \]
        4. +-commutativeN/A

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

          \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 \cdot \left(1 + \left(-1 \cdot x + -1 \cdot \frac{x - 1}{y}\right)\right)}{y}\right)} \]
      5. Simplified99.8%

        \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + \left(x + \frac{-1 + x}{y}\right)}{y}\right)} \]
    3. Recombined 2 regimes into one program.
    4. Final simplification99.9%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{-1 + \left(x + \frac{x + -1}{y}\right)}{y}\right)\\ \end{array} \]
    5. Add Preprocessing

    Alternative 5: 79.9% accurate, 0.8× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{x - y}{1 - y}\\ \mathbf{if}\;t\_0 \leq -5:\\ \;\;\;\;1 - \log \left(-x\right)\\ \mathbf{elif}\;t\_0 \leq 0.5:\\ \;\;\;\;\left(x - y\right) + 1\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(-y\right)\\ \end{array} \end{array} \]
    (FPCore (x y)
     :precision binary64
     (let* ((t_0 (/ (- x y) (- 1.0 y))))
       (if (<= t_0 -5.0)
         (- 1.0 (log (- x)))
         (if (<= t_0 0.5) (+ (- x y) 1.0) (+ 1.0 (log (- y)))))))
    double code(double x, double y) {
    	double t_0 = (x - y) / (1.0 - y);
    	double tmp;
    	if (t_0 <= -5.0) {
    		tmp = 1.0 - log(-x);
    	} else if (t_0 <= 0.5) {
    		tmp = (x - y) + 1.0;
    	} else {
    		tmp = 1.0 + log(-y);
    	}
    	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 - y) / (1.0d0 - y)
        if (t_0 <= (-5.0d0)) then
            tmp = 1.0d0 - log(-x)
        else if (t_0 <= 0.5d0) then
            tmp = (x - y) + 1.0d0
        else
            tmp = 1.0d0 + log(-y)
        end if
        code = tmp
    end function
    
    public static double code(double x, double y) {
    	double t_0 = (x - y) / (1.0 - y);
    	double tmp;
    	if (t_0 <= -5.0) {
    		tmp = 1.0 - Math.log(-x);
    	} else if (t_0 <= 0.5) {
    		tmp = (x - y) + 1.0;
    	} else {
    		tmp = 1.0 + Math.log(-y);
    	}
    	return tmp;
    }
    
    def code(x, y):
    	t_0 = (x - y) / (1.0 - y)
    	tmp = 0
    	if t_0 <= -5.0:
    		tmp = 1.0 - math.log(-x)
    	elif t_0 <= 0.5:
    		tmp = (x - y) + 1.0
    	else:
    		tmp = 1.0 + math.log(-y)
    	return tmp
    
    function code(x, y)
    	t_0 = Float64(Float64(x - y) / Float64(1.0 - y))
    	tmp = 0.0
    	if (t_0 <= -5.0)
    		tmp = Float64(1.0 - log(Float64(-x)));
    	elseif (t_0 <= 0.5)
    		tmp = Float64(Float64(x - y) + 1.0);
    	else
    		tmp = Float64(1.0 + log(Float64(-y)));
    	end
    	return tmp
    end
    
    function tmp_2 = code(x, y)
    	t_0 = (x - y) / (1.0 - y);
    	tmp = 0.0;
    	if (t_0 <= -5.0)
    		tmp = 1.0 - log(-x);
    	elseif (t_0 <= 0.5)
    		tmp = (x - y) + 1.0;
    	else
    		tmp = 1.0 + log(-y);
    	end
    	tmp_2 = tmp;
    end
    
    code[x_, y_] := Block[{t$95$0 = N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -5.0], N[(1.0 - N[Log[(-x)], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 0.5], N[(N[(x - y), $MachinePrecision] + 1.0), $MachinePrecision], N[(1.0 + N[Log[(-y)], $MachinePrecision]), $MachinePrecision]]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := \frac{x - y}{1 - y}\\
    \mathbf{if}\;t\_0 \leq -5:\\
    \;\;\;\;1 - \log \left(-x\right)\\
    
    \mathbf{elif}\;t\_0 \leq 0.5:\\
    \;\;\;\;\left(x - y\right) + 1\\
    
    \mathbf{else}:\\
    \;\;\;\;1 + \log \left(-y\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < -5

      1. Initial program 100.0%

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

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

          \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{x}{1 - y}\right)\right)} \]
        2. distribute-neg-frac2N/A

          \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)} \]
        3. /-lowering-/.f64N/A

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

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

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

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

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

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

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

          \[\leadsto 1 - \log \left(\frac{x}{y + \color{blue}{-1}}\right) \]
        11. +-lowering-+.f6497.8

          \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{y + -1}}\right) \]
      5. Simplified97.8%

        \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{y + -1}\right)} \]
      6. Taylor expanded in y around 0

        \[\leadsto \color{blue}{1 - \log \left(-1 \cdot x\right)} \]
      7. Step-by-step derivation
        1. --lowering--.f64N/A

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

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

          \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(x\right)\right)} \]
        4. neg-lowering-neg.f6467.6

          \[\leadsto 1 - \log \color{blue}{\left(-x\right)} \]
      8. Simplified67.6%

        \[\leadsto \color{blue}{1 - \log \left(-x\right)} \]

      if -5 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.5

      1. Initial program 99.9%

        \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
      2. Add Preprocessing
      3. Taylor expanded in y around 0

        \[\leadsto \color{blue}{\left(1 + -1 \cdot \left(y \cdot \left(-1 \cdot \frac{x}{1 - x} + \frac{1}{1 - x}\right)\right)\right) - \log \left(1 - x\right)} \]
      4. Step-by-step derivation
        1. Simplified97.4%

          \[\leadsto \color{blue}{\left(1 - y\right) - \mathsf{log1p}\left(-x\right)} \]
        2. Taylor expanded in x around 0

          \[\leadsto \color{blue}{\left(1 + x\right) - y} \]
        3. Step-by-step derivation
          1. associate--l+N/A

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

            \[\leadsto \color{blue}{1 + \left(x - y\right)} \]
          3. --lowering--.f6496.0

            \[\leadsto 1 + \color{blue}{\left(x - y\right)} \]
        4. Simplified96.0%

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

        if 0.5 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

        1. Initial program 8.3%

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

          \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
        4. Step-by-step derivation
          1. mul-1-negN/A

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

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

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

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

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

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

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
          8. /-lowering-/.f64N/A

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

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

            \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
          11. +-commutativeN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
          12. +-lowering-+.f6499.2

            \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
        5. Simplified99.2%

          \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + x}{y}\right)} \]
        6. Step-by-step derivation
          1. sub-negN/A

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

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

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

            \[\leadsto \color{blue}{\log \left(\frac{1}{\frac{-1 + x}{y}}\right)} + 1 \]
          5. clear-numN/A

            \[\leadsto \log \color{blue}{\left(\frac{y}{-1 + x}\right)} + 1 \]
          6. log-lowering-log.f64N/A

            \[\leadsto \color{blue}{\log \left(\frac{y}{-1 + x}\right)} + 1 \]
          7. /-lowering-/.f64N/A

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

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

            \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
        7. Applied egg-rr99.2%

          \[\leadsto \color{blue}{\log \left(\frac{y}{x + -1}\right) + 1} \]
        8. Taylor expanded in x around 0

          \[\leadsto \color{blue}{\log \left(-1 \cdot y\right)} + 1 \]
        9. Step-by-step derivation
          1. log-lowering-log.f64N/A

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

            \[\leadsto \log \color{blue}{\left(\mathsf{neg}\left(y\right)\right)} + 1 \]
          3. neg-lowering-neg.f6474.6

            \[\leadsto \log \color{blue}{\left(-y\right)} + 1 \]
        10. Simplified74.6%

          \[\leadsto \color{blue}{\log \left(-y\right)} + 1 \]
      5. Recombined 3 regimes into one program.
      6. Final simplification80.8%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq -5:\\ \;\;\;\;1 - \log \left(-x\right)\\ \mathbf{elif}\;\frac{x - y}{1 - y} \leq 0.5:\\ \;\;\;\;\left(x - y\right) + 1\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(-y\right)\\ \end{array} \]
      7. Add Preprocessing

      Alternative 6: 99.8% accurate, 0.9× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.999999:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x + -1}\right)\\ \end{array} \end{array} \]
      (FPCore (x y)
       :precision binary64
       (if (<= (/ (- x y) (- 1.0 y)) 0.999999)
         (- 1.0 (log1p (/ (- x y) (+ y -1.0))))
         (+ 1.0 (log (/ y (+ x -1.0))))))
      double code(double x, double y) {
      	double tmp;
      	if (((x - y) / (1.0 - y)) <= 0.999999) {
      		tmp = 1.0 - log1p(((x - y) / (y + -1.0)));
      	} else {
      		tmp = 1.0 + log((y / (x + -1.0)));
      	}
      	return tmp;
      }
      
      public static double code(double x, double y) {
      	double tmp;
      	if (((x - y) / (1.0 - y)) <= 0.999999) {
      		tmp = 1.0 - Math.log1p(((x - y) / (y + -1.0)));
      	} else {
      		tmp = 1.0 + Math.log((y / (x + -1.0)));
      	}
      	return tmp;
      }
      
      def code(x, y):
      	tmp = 0
      	if ((x - y) / (1.0 - y)) <= 0.999999:
      		tmp = 1.0 - math.log1p(((x - y) / (y + -1.0)))
      	else:
      		tmp = 1.0 + math.log((y / (x + -1.0)))
      	return tmp
      
      function code(x, y)
      	tmp = 0.0
      	if (Float64(Float64(x - y) / Float64(1.0 - y)) <= 0.999999)
      		tmp = Float64(1.0 - log1p(Float64(Float64(x - y) / Float64(y + -1.0))));
      	else
      		tmp = Float64(1.0 + log(Float64(y / Float64(x + -1.0))));
      	end
      	return tmp
      end
      
      code[x_, y_] := If[LessEqual[N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision], 0.999999], N[(1.0 - N[Log[1 + N[(N[(x - y), $MachinePrecision] / N[(y + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(1.0 + N[Log[N[(y / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.999999:\\
      \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;1 + \log \left(\frac{y}{x + -1}\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.999998999999999971

        1. Initial program 99.8%

          \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. sub-negN/A

            \[\leadsto 1 - \log \color{blue}{\left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)} \]
          2. accelerator-lowering-log1p.f64N/A

            \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)} \]
          3. distribute-neg-frac2N/A

            \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}}\right) \]
          4. /-lowering-/.f64N/A

            \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}}\right) \]
          5. --lowering--.f64N/A

            \[\leadsto 1 - \mathsf{log1p}\left(\frac{\color{blue}{x - y}}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right) \]
          6. sub-negN/A

            \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\mathsf{neg}\left(\color{blue}{\left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)}\right)}\right) \]
          7. +-commutativeN/A

            \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\mathsf{neg}\left(\color{blue}{\left(\left(\mathsf{neg}\left(y\right)\right) + 1\right)}\right)}\right) \]
          8. distribute-neg-inN/A

            \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(y\right)\right)\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}}\right) \]
          9. remove-double-negN/A

            \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\color{blue}{y} + \left(\mathsf{neg}\left(1\right)\right)}\right) \]
          10. metadata-evalN/A

            \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{y + \color{blue}{-1}}\right) \]
          11. +-lowering-+.f6499.8

            \[\leadsto 1 - \mathsf{log1p}\left(\frac{x - y}{\color{blue}{y + -1}}\right) \]
        4. Applied egg-rr99.8%

          \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]

        if 0.999998999999999971 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

        1. Initial program 6.2%

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

          \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
        4. Step-by-step derivation
          1. mul-1-negN/A

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

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

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

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

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

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

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
          8. /-lowering-/.f64N/A

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

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

            \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
          11. +-commutativeN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
          12. +-lowering-+.f6499.8

            \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
        5. Simplified99.8%

          \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + x}{y}\right)} \]
        6. Step-by-step derivation
          1. sub-negN/A

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

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

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

            \[\leadsto \color{blue}{\log \left(\frac{1}{\frac{-1 + x}{y}}\right)} + 1 \]
          5. clear-numN/A

            \[\leadsto \log \color{blue}{\left(\frac{y}{-1 + x}\right)} + 1 \]
          6. log-lowering-log.f64N/A

            \[\leadsto \color{blue}{\log \left(\frac{y}{-1 + x}\right)} + 1 \]
          7. /-lowering-/.f64N/A

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

            \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
          9. +-lowering-+.f6499.8

            \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
        7. Applied egg-rr99.8%

          \[\leadsto \color{blue}{\log \left(\frac{y}{x + -1}\right) + 1} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification99.8%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.999999:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x + -1}\right)\\ \end{array} \]
      5. Add Preprocessing

      Alternative 7: 98.8% accurate, 1.0× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + \log \left(\frac{y}{x + -1}\right)\\ \mathbf{if}\;y \leq -1.75:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
      (FPCore (x y)
       :precision binary64
       (let* ((t_0 (+ 1.0 (log (/ y (+ x -1.0))))))
         (if (<= y -1.75) t_0 (if (<= y 1.0) (- (- 1.0 y) (log1p (- x))) t_0))))
      double code(double x, double y) {
      	double t_0 = 1.0 + log((y / (x + -1.0)));
      	double tmp;
      	if (y <= -1.75) {
      		tmp = t_0;
      	} else if (y <= 1.0) {
      		tmp = (1.0 - y) - log1p(-x);
      	} else {
      		tmp = t_0;
      	}
      	return tmp;
      }
      
      public static double code(double x, double y) {
      	double t_0 = 1.0 + Math.log((y / (x + -1.0)));
      	double tmp;
      	if (y <= -1.75) {
      		tmp = t_0;
      	} else if (y <= 1.0) {
      		tmp = (1.0 - y) - Math.log1p(-x);
      	} else {
      		tmp = t_0;
      	}
      	return tmp;
      }
      
      def code(x, y):
      	t_0 = 1.0 + math.log((y / (x + -1.0)))
      	tmp = 0
      	if y <= -1.75:
      		tmp = t_0
      	elif y <= 1.0:
      		tmp = (1.0 - y) - math.log1p(-x)
      	else:
      		tmp = t_0
      	return tmp
      
      function code(x, y)
      	t_0 = Float64(1.0 + log(Float64(y / Float64(x + -1.0))))
      	tmp = 0.0
      	if (y <= -1.75)
      		tmp = t_0;
      	elseif (y <= 1.0)
      		tmp = Float64(Float64(1.0 - y) - log1p(Float64(-x)));
      	else
      		tmp = t_0;
      	end
      	return tmp
      end
      
      code[x_, y_] := Block[{t$95$0 = N[(1.0 + N[Log[N[(y / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -1.75], t$95$0, If[LessEqual[y, 1.0], N[(N[(1.0 - y), $MachinePrecision] - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision], t$95$0]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := 1 + \log \left(\frac{y}{x + -1}\right)\\
      \mathbf{if}\;y \leq -1.75:\\
      \;\;\;\;t\_0\\
      
      \mathbf{elif}\;y \leq 1:\\
      \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;t\_0\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if y < -1.75 or 1 < y

        1. Initial program 28.8%

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

          \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
        4. Step-by-step derivation
          1. mul-1-negN/A

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

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

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

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

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

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

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
          8. /-lowering-/.f64N/A

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

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

            \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
          11. +-commutativeN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
          12. +-lowering-+.f6498.8

            \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
        5. Simplified98.8%

          \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + x}{y}\right)} \]
        6. Step-by-step derivation
          1. sub-negN/A

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

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

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

            \[\leadsto \color{blue}{\log \left(\frac{1}{\frac{-1 + x}{y}}\right)} + 1 \]
          5. clear-numN/A

            \[\leadsto \log \color{blue}{\left(\frac{y}{-1 + x}\right)} + 1 \]
          6. log-lowering-log.f64N/A

            \[\leadsto \color{blue}{\log \left(\frac{y}{-1 + x}\right)} + 1 \]
          7. /-lowering-/.f64N/A

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

            \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
          9. +-lowering-+.f6498.8

            \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
        7. Applied egg-rr98.8%

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

        if -1.75 < y < 1

        1. Initial program 99.9%

          \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
        2. Add Preprocessing
        3. Taylor expanded in y around 0

          \[\leadsto \color{blue}{\left(1 + -1 \cdot \left(y \cdot \left(-1 \cdot \frac{x}{1 - x} + \frac{1}{1 - x}\right)\right)\right) - \log \left(1 - x\right)} \]
        4. Step-by-step derivation
          1. Simplified98.1%

            \[\leadsto \color{blue}{\left(1 - y\right) - \mathsf{log1p}\left(-x\right)} \]
        5. Recombined 2 regimes into one program.
        6. Final simplification98.4%

          \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.75:\\ \;\;\;\;1 + \log \left(\frac{y}{x + -1}\right)\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x + -1}\right)\\ \end{array} \]
        7. Add Preprocessing

        Alternative 8: 80.2% accurate, 1.0× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\ \;\;\;\;1 - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(-y\right)\\ \end{array} \end{array} \]
        (FPCore (x y)
         :precision binary64
         (if (<= (/ (- x y) (- 1.0 y)) 0.5) (- 1.0 (log1p (- x))) (+ 1.0 (log (- y)))))
        double code(double x, double y) {
        	double tmp;
        	if (((x - y) / (1.0 - y)) <= 0.5) {
        		tmp = 1.0 - log1p(-x);
        	} else {
        		tmp = 1.0 + log(-y);
        	}
        	return tmp;
        }
        
        public static double code(double x, double y) {
        	double tmp;
        	if (((x - y) / (1.0 - y)) <= 0.5) {
        		tmp = 1.0 - Math.log1p(-x);
        	} else {
        		tmp = 1.0 + Math.log(-y);
        	}
        	return tmp;
        }
        
        def code(x, y):
        	tmp = 0
        	if ((x - y) / (1.0 - y)) <= 0.5:
        		tmp = 1.0 - math.log1p(-x)
        	else:
        		tmp = 1.0 + math.log(-y)
        	return tmp
        
        function code(x, y)
        	tmp = 0.0
        	if (Float64(Float64(x - y) / Float64(1.0 - y)) <= 0.5)
        		tmp = Float64(1.0 - log1p(Float64(-x)));
        	else
        		tmp = Float64(1.0 + log(Float64(-y)));
        	end
        	return tmp
        end
        
        code[x_, y_] := If[LessEqual[N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision], 0.5], N[(1.0 - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision], N[(1.0 + N[Log[(-y)], $MachinePrecision]), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\
        \;\;\;\;1 - \mathsf{log1p}\left(-x\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;1 + \log \left(-y\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.5

          1. Initial program 99.9%

            \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
          2. Add Preprocessing
          3. Taylor expanded in y around 0

            \[\leadsto 1 - \color{blue}{\log \left(1 - x\right)} \]
          4. Step-by-step derivation
            1. sub-negN/A

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

              \[\leadsto 1 - \log \left(1 + \color{blue}{-1 \cdot x}\right) \]
            3. accelerator-lowering-log1p.f64N/A

              \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-1 \cdot x\right)} \]
            4. mul-1-negN/A

              \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\mathsf{neg}\left(x\right)}\right) \]
            5. neg-lowering-neg.f6484.3

              \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{-x}\right) \]
          5. Simplified84.3%

            \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-x\right)} \]

          if 0.5 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

          1. Initial program 8.3%

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

            \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
          4. Step-by-step derivation
            1. mul-1-negN/A

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

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

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

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

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

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

              \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
            8. /-lowering-/.f64N/A

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

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

              \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
            11. +-commutativeN/A

              \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
            12. +-lowering-+.f6499.2

              \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
          5. Simplified99.2%

            \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + x}{y}\right)} \]
          6. Step-by-step derivation
            1. sub-negN/A

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

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

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

              \[\leadsto \color{blue}{\log \left(\frac{1}{\frac{-1 + x}{y}}\right)} + 1 \]
            5. clear-numN/A

              \[\leadsto \log \color{blue}{\left(\frac{y}{-1 + x}\right)} + 1 \]
            6. log-lowering-log.f64N/A

              \[\leadsto \color{blue}{\log \left(\frac{y}{-1 + x}\right)} + 1 \]
            7. /-lowering-/.f64N/A

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

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

              \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
          7. Applied egg-rr99.2%

            \[\leadsto \color{blue}{\log \left(\frac{y}{x + -1}\right) + 1} \]
          8. Taylor expanded in x around 0

            \[\leadsto \color{blue}{\log \left(-1 \cdot y\right)} + 1 \]
          9. Step-by-step derivation
            1. log-lowering-log.f64N/A

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

              \[\leadsto \log \color{blue}{\left(\mathsf{neg}\left(y\right)\right)} + 1 \]
            3. neg-lowering-neg.f6474.6

              \[\leadsto \log \color{blue}{\left(-y\right)} + 1 \]
          10. Simplified74.6%

            \[\leadsto \color{blue}{\log \left(-y\right)} + 1 \]
        3. Recombined 2 regimes into one program.
        4. Final simplification81.3%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\ \;\;\;\;1 - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(-y\right)\\ \end{array} \]
        5. Add Preprocessing

        Alternative 9: 61.1% accurate, 1.0× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\ \;\;\;\;\left(x - y\right) + 1\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(-y\right)\\ \end{array} \end{array} \]
        (FPCore (x y)
         :precision binary64
         (if (<= (/ (- x y) (- 1.0 y)) 0.5) (+ (- x y) 1.0) (+ 1.0 (log (- y)))))
        double code(double x, double y) {
        	double tmp;
        	if (((x - y) / (1.0 - y)) <= 0.5) {
        		tmp = (x - y) + 1.0;
        	} else {
        		tmp = 1.0 + log(-y);
        	}
        	return tmp;
        }
        
        real(8) function code(x, y)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            real(8) :: tmp
            if (((x - y) / (1.0d0 - y)) <= 0.5d0) then
                tmp = (x - y) + 1.0d0
            else
                tmp = 1.0d0 + log(-y)
            end if
            code = tmp
        end function
        
        public static double code(double x, double y) {
        	double tmp;
        	if (((x - y) / (1.0 - y)) <= 0.5) {
        		tmp = (x - y) + 1.0;
        	} else {
        		tmp = 1.0 + Math.log(-y);
        	}
        	return tmp;
        }
        
        def code(x, y):
        	tmp = 0
        	if ((x - y) / (1.0 - y)) <= 0.5:
        		tmp = (x - y) + 1.0
        	else:
        		tmp = 1.0 + math.log(-y)
        	return tmp
        
        function code(x, y)
        	tmp = 0.0
        	if (Float64(Float64(x - y) / Float64(1.0 - y)) <= 0.5)
        		tmp = Float64(Float64(x - y) + 1.0);
        	else
        		tmp = Float64(1.0 + log(Float64(-y)));
        	end
        	return tmp
        end
        
        function tmp_2 = code(x, y)
        	tmp = 0.0;
        	if (((x - y) / (1.0 - y)) <= 0.5)
        		tmp = (x - y) + 1.0;
        	else
        		tmp = 1.0 + log(-y);
        	end
        	tmp_2 = tmp;
        end
        
        code[x_, y_] := If[LessEqual[N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision], 0.5], N[(N[(x - y), $MachinePrecision] + 1.0), $MachinePrecision], N[(1.0 + N[Log[(-y)], $MachinePrecision]), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\
        \;\;\;\;\left(x - y\right) + 1\\
        
        \mathbf{else}:\\
        \;\;\;\;1 + \log \left(-y\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.5

          1. Initial program 99.9%

            \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
          2. Add Preprocessing
          3. Taylor expanded in y around 0

            \[\leadsto \color{blue}{\left(1 + -1 \cdot \left(y \cdot \left(-1 \cdot \frac{x}{1 - x} + \frac{1}{1 - x}\right)\right)\right) - \log \left(1 - x\right)} \]
          4. Step-by-step derivation
            1. Simplified85.3%

              \[\leadsto \color{blue}{\left(1 - y\right) - \mathsf{log1p}\left(-x\right)} \]
            2. Taylor expanded in x around 0

              \[\leadsto \color{blue}{\left(1 + x\right) - y} \]
            3. Step-by-step derivation
              1. associate--l+N/A

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

                \[\leadsto \color{blue}{1 + \left(x - y\right)} \]
              3. --lowering--.f6455.9

                \[\leadsto 1 + \color{blue}{\left(x - y\right)} \]
            4. Simplified55.9%

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

            if 0.5 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

            1. Initial program 8.3%

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

              \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
            4. Step-by-step derivation
              1. mul-1-negN/A

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

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

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

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

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

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

                \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
              8. /-lowering-/.f64N/A

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

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

                \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
              11. +-commutativeN/A

                \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
              12. +-lowering-+.f6499.2

                \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
            5. Simplified99.2%

              \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + x}{y}\right)} \]
            6. Step-by-step derivation
              1. sub-negN/A

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

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

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

                \[\leadsto \color{blue}{\log \left(\frac{1}{\frac{-1 + x}{y}}\right)} + 1 \]
              5. clear-numN/A

                \[\leadsto \log \color{blue}{\left(\frac{y}{-1 + x}\right)} + 1 \]
              6. log-lowering-log.f64N/A

                \[\leadsto \color{blue}{\log \left(\frac{y}{-1 + x}\right)} + 1 \]
              7. /-lowering-/.f64N/A

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

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

                \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
            7. Applied egg-rr99.2%

              \[\leadsto \color{blue}{\log \left(\frac{y}{x + -1}\right) + 1} \]
            8. Taylor expanded in x around 0

              \[\leadsto \color{blue}{\log \left(-1 \cdot y\right)} + 1 \]
            9. Step-by-step derivation
              1. log-lowering-log.f64N/A

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

                \[\leadsto \log \color{blue}{\left(\mathsf{neg}\left(y\right)\right)} + 1 \]
              3. neg-lowering-neg.f6474.6

                \[\leadsto \log \color{blue}{\left(-y\right)} + 1 \]
            10. Simplified74.6%

              \[\leadsto \color{blue}{\log \left(-y\right)} + 1 \]
          5. Recombined 2 regimes into one program.
          6. Final simplification61.7%

            \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.5:\\ \;\;\;\;\left(x - y\right) + 1\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(-y\right)\\ \end{array} \]
          7. Add Preprocessing

          Alternative 10: 90.1% accurate, 1.0× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -15.2:\\ \;\;\;\;1 + \log \left(-y\right)\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{x}{y}\right)\\ \end{array} \end{array} \]
          (FPCore (x y)
           :precision binary64
           (if (<= y -15.2)
             (+ 1.0 (log (- y)))
             (if (<= y 1.0) (- (- 1.0 y) (log1p (- x))) (- 1.0 (log (/ x y))))))
          double code(double x, double y) {
          	double tmp;
          	if (y <= -15.2) {
          		tmp = 1.0 + log(-y);
          	} else if (y <= 1.0) {
          		tmp = (1.0 - y) - log1p(-x);
          	} else {
          		tmp = 1.0 - log((x / y));
          	}
          	return tmp;
          }
          
          public static double code(double x, double y) {
          	double tmp;
          	if (y <= -15.2) {
          		tmp = 1.0 + Math.log(-y);
          	} else if (y <= 1.0) {
          		tmp = (1.0 - y) - Math.log1p(-x);
          	} else {
          		tmp = 1.0 - Math.log((x / y));
          	}
          	return tmp;
          }
          
          def code(x, y):
          	tmp = 0
          	if y <= -15.2:
          		tmp = 1.0 + math.log(-y)
          	elif y <= 1.0:
          		tmp = (1.0 - y) - math.log1p(-x)
          	else:
          		tmp = 1.0 - math.log((x / y))
          	return tmp
          
          function code(x, y)
          	tmp = 0.0
          	if (y <= -15.2)
          		tmp = Float64(1.0 + log(Float64(-y)));
          	elseif (y <= 1.0)
          		tmp = Float64(Float64(1.0 - y) - log1p(Float64(-x)));
          	else
          		tmp = Float64(1.0 - log(Float64(x / y)));
          	end
          	return tmp
          end
          
          code[x_, y_] := If[LessEqual[y, -15.2], N[(1.0 + N[Log[(-y)], $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 1.0], N[(N[(1.0 - y), $MachinePrecision] - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;y \leq -15.2:\\
          \;\;\;\;1 + \log \left(-y\right)\\
          
          \mathbf{elif}\;y \leq 1:\\
          \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\
          
          \mathbf{else}:\\
          \;\;\;\;1 - \log \left(\frac{x}{y}\right)\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 3 regimes
          2. if y < -15.199999999999999

            1. Initial program 12.8%

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

              \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
            4. Step-by-step derivation
              1. mul-1-negN/A

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

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

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

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

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

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

                \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
              8. /-lowering-/.f64N/A

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

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

                \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
              11. +-commutativeN/A

                \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
              12. +-lowering-+.f6499.2

                \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
            5. Simplified99.2%

              \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + x}{y}\right)} \]
            6. Step-by-step derivation
              1. sub-negN/A

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

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

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

                \[\leadsto \color{blue}{\log \left(\frac{1}{\frac{-1 + x}{y}}\right)} + 1 \]
              5. clear-numN/A

                \[\leadsto \log \color{blue}{\left(\frac{y}{-1 + x}\right)} + 1 \]
              6. log-lowering-log.f64N/A

                \[\leadsto \color{blue}{\log \left(\frac{y}{-1 + x}\right)} + 1 \]
              7. /-lowering-/.f64N/A

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

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

                \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
            7. Applied egg-rr99.2%

              \[\leadsto \color{blue}{\log \left(\frac{y}{x + -1}\right) + 1} \]
            8. Taylor expanded in x around 0

              \[\leadsto \color{blue}{\log \left(-1 \cdot y\right)} + 1 \]
            9. Step-by-step derivation
              1. log-lowering-log.f64N/A

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

                \[\leadsto \log \color{blue}{\left(\mathsf{neg}\left(y\right)\right)} + 1 \]
              3. neg-lowering-neg.f6477.6

                \[\leadsto \log \color{blue}{\left(-y\right)} + 1 \]
            10. Simplified77.6%

              \[\leadsto \color{blue}{\log \left(-y\right)} + 1 \]

            if -15.199999999999999 < y < 1

            1. Initial program 99.9%

              \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
            2. Add Preprocessing
            3. Taylor expanded in y around 0

              \[\leadsto \color{blue}{\left(1 + -1 \cdot \left(y \cdot \left(-1 \cdot \frac{x}{1 - x} + \frac{1}{1 - x}\right)\right)\right) - \log \left(1 - x\right)} \]
            4. Step-by-step derivation
              1. Simplified98.1%

                \[\leadsto \color{blue}{\left(1 - y\right) - \mathsf{log1p}\left(-x\right)} \]

              if 1 < y

              1. Initial program 75.9%

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

                \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
              4. Step-by-step derivation
                1. mul-1-negN/A

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

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

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

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

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

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

                  \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
                8. /-lowering-/.f64N/A

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

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

                  \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
                11. +-commutativeN/A

                  \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
                12. +-lowering-+.f6497.8

                  \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
              5. Simplified97.8%

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

                \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{y}\right)} \]
              7. Step-by-step derivation
                1. /-lowering-/.f6494.9

                  \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{y}\right)} \]
              8. Simplified94.9%

                \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{y}\right)} \]
            5. Recombined 3 regimes into one program.
            6. Final simplification91.6%

              \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -15.2:\\ \;\;\;\;1 + \log \left(-y\right)\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{x}{y}\right)\\ \end{array} \]
            7. Add Preprocessing

            Alternative 11: 90.1% accurate, 1.0× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -25:\\ \;\;\;\;1 + \log \left(-y\right)\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x}\right)\\ \end{array} \end{array} \]
            (FPCore (x y)
             :precision binary64
             (if (<= y -25.0)
               (+ 1.0 (log (- y)))
               (if (<= y 1.0) (- (- 1.0 y) (log1p (- x))) (+ 1.0 (log (/ y x))))))
            double code(double x, double y) {
            	double tmp;
            	if (y <= -25.0) {
            		tmp = 1.0 + log(-y);
            	} else if (y <= 1.0) {
            		tmp = (1.0 - y) - log1p(-x);
            	} else {
            		tmp = 1.0 + log((y / x));
            	}
            	return tmp;
            }
            
            public static double code(double x, double y) {
            	double tmp;
            	if (y <= -25.0) {
            		tmp = 1.0 + Math.log(-y);
            	} else if (y <= 1.0) {
            		tmp = (1.0 - y) - Math.log1p(-x);
            	} else {
            		tmp = 1.0 + Math.log((y / x));
            	}
            	return tmp;
            }
            
            def code(x, y):
            	tmp = 0
            	if y <= -25.0:
            		tmp = 1.0 + math.log(-y)
            	elif y <= 1.0:
            		tmp = (1.0 - y) - math.log1p(-x)
            	else:
            		tmp = 1.0 + math.log((y / x))
            	return tmp
            
            function code(x, y)
            	tmp = 0.0
            	if (y <= -25.0)
            		tmp = Float64(1.0 + log(Float64(-y)));
            	elseif (y <= 1.0)
            		tmp = Float64(Float64(1.0 - y) - log1p(Float64(-x)));
            	else
            		tmp = Float64(1.0 + log(Float64(y / x)));
            	end
            	return tmp
            end
            
            code[x_, y_] := If[LessEqual[y, -25.0], N[(1.0 + N[Log[(-y)], $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 1.0], N[(N[(1.0 - y), $MachinePrecision] - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision], N[(1.0 + N[Log[N[(y / x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;y \leq -25:\\
            \;\;\;\;1 + \log \left(-y\right)\\
            
            \mathbf{elif}\;y \leq 1:\\
            \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;1 + \log \left(\frac{y}{x}\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 3 regimes
            2. if y < -25

              1. Initial program 12.8%

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

                \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
              4. Step-by-step derivation
                1. mul-1-negN/A

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

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

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

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

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

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

                  \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
                8. /-lowering-/.f64N/A

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

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

                  \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
                11. +-commutativeN/A

                  \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
                12. +-lowering-+.f6499.2

                  \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
              5. Simplified99.2%

                \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + x}{y}\right)} \]
              6. Step-by-step derivation
                1. sub-negN/A

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

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

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

                  \[\leadsto \color{blue}{\log \left(\frac{1}{\frac{-1 + x}{y}}\right)} + 1 \]
                5. clear-numN/A

                  \[\leadsto \log \color{blue}{\left(\frac{y}{-1 + x}\right)} + 1 \]
                6. log-lowering-log.f64N/A

                  \[\leadsto \color{blue}{\log \left(\frac{y}{-1 + x}\right)} + 1 \]
                7. /-lowering-/.f64N/A

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

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

                  \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
              7. Applied egg-rr99.2%

                \[\leadsto \color{blue}{\log \left(\frac{y}{x + -1}\right) + 1} \]
              8. Taylor expanded in x around 0

                \[\leadsto \color{blue}{\log \left(-1 \cdot y\right)} + 1 \]
              9. Step-by-step derivation
                1. log-lowering-log.f64N/A

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

                  \[\leadsto \log \color{blue}{\left(\mathsf{neg}\left(y\right)\right)} + 1 \]
                3. neg-lowering-neg.f6477.6

                  \[\leadsto \log \color{blue}{\left(-y\right)} + 1 \]
              10. Simplified77.6%

                \[\leadsto \color{blue}{\log \left(-y\right)} + 1 \]

              if -25 < y < 1

              1. Initial program 99.9%

                \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
              2. Add Preprocessing
              3. Taylor expanded in y around 0

                \[\leadsto \color{blue}{\left(1 + -1 \cdot \left(y \cdot \left(-1 \cdot \frac{x}{1 - x} + \frac{1}{1 - x}\right)\right)\right) - \log \left(1 - x\right)} \]
              4. Step-by-step derivation
                1. Simplified98.1%

                  \[\leadsto \color{blue}{\left(1 - y\right) - \mathsf{log1p}\left(-x\right)} \]

                if 1 < y

                1. Initial program 75.9%

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

                  \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
                4. Step-by-step derivation
                  1. mul-1-negN/A

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

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

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

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

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

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

                    \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
                  8. /-lowering-/.f64N/A

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

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

                    \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
                  11. +-commutativeN/A

                    \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
                  12. +-lowering-+.f6497.8

                    \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
                5. Simplified97.8%

                  \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + x}{y}\right)} \]
                6. Step-by-step derivation
                  1. sub-negN/A

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

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

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

                    \[\leadsto \color{blue}{\log \left(\frac{1}{\frac{-1 + x}{y}}\right)} + 1 \]
                  5. clear-numN/A

                    \[\leadsto \log \color{blue}{\left(\frac{y}{-1 + x}\right)} + 1 \]
                  6. log-lowering-log.f64N/A

                    \[\leadsto \color{blue}{\log \left(\frac{y}{-1 + x}\right)} + 1 \]
                  7. /-lowering-/.f64N/A

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

                    \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
                  9. +-lowering-+.f6497.8

                    \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
                7. Applied egg-rr97.8%

                  \[\leadsto \color{blue}{\log \left(\frac{y}{x + -1}\right) + 1} \]
                8. Taylor expanded in x around inf

                  \[\leadsto \log \color{blue}{\left(\frac{y}{x}\right)} + 1 \]
                9. Step-by-step derivation
                  1. /-lowering-/.f6494.9

                    \[\leadsto \log \color{blue}{\left(\frac{y}{x}\right)} + 1 \]
                10. Simplified94.9%

                  \[\leadsto \log \color{blue}{\left(\frac{y}{x}\right)} + 1 \]
              5. Recombined 3 regimes into one program.
              6. Final simplification91.6%

                \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -25:\\ \;\;\;\;1 + \log \left(-y\right)\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x}\right)\\ \end{array} \]
              7. Add Preprocessing

              Alternative 12: 80.0% accurate, 1.1× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -11.5:\\ \;\;\;\;1 + \log \left(-y\right)\\ \mathbf{else}:\\ \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\ \end{array} \end{array} \]
              (FPCore (x y)
               :precision binary64
               (if (<= y -11.5) (+ 1.0 (log (- y))) (- (- 1.0 y) (log1p (- x)))))
              double code(double x, double y) {
              	double tmp;
              	if (y <= -11.5) {
              		tmp = 1.0 + log(-y);
              	} else {
              		tmp = (1.0 - y) - log1p(-x);
              	}
              	return tmp;
              }
              
              public static double code(double x, double y) {
              	double tmp;
              	if (y <= -11.5) {
              		tmp = 1.0 + Math.log(-y);
              	} else {
              		tmp = (1.0 - y) - Math.log1p(-x);
              	}
              	return tmp;
              }
              
              def code(x, y):
              	tmp = 0
              	if y <= -11.5:
              		tmp = 1.0 + math.log(-y)
              	else:
              		tmp = (1.0 - y) - math.log1p(-x)
              	return tmp
              
              function code(x, y)
              	tmp = 0.0
              	if (y <= -11.5)
              		tmp = Float64(1.0 + log(Float64(-y)));
              	else
              		tmp = Float64(Float64(1.0 - y) - log1p(Float64(-x)));
              	end
              	return tmp
              end
              
              code[x_, y_] := If[LessEqual[y, -11.5], N[(1.0 + N[Log[(-y)], $MachinePrecision]), $MachinePrecision], N[(N[(1.0 - y), $MachinePrecision] - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;y \leq -11.5:\\
              \;\;\;\;1 + \log \left(-y\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if y < -11.5

                1. Initial program 12.8%

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

                  \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
                4. Step-by-step derivation
                  1. mul-1-negN/A

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

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

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

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

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

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

                    \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
                  8. /-lowering-/.f64N/A

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

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

                    \[\leadsto 1 - \log \left(\frac{x + \color{blue}{-1}}{y}\right) \]
                  11. +-commutativeN/A

                    \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
                  12. +-lowering-+.f6499.2

                    \[\leadsto 1 - \log \left(\frac{\color{blue}{-1 + x}}{y}\right) \]
                5. Simplified99.2%

                  \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 + x}{y}\right)} \]
                6. Step-by-step derivation
                  1. sub-negN/A

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

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

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

                    \[\leadsto \color{blue}{\log \left(\frac{1}{\frac{-1 + x}{y}}\right)} + 1 \]
                  5. clear-numN/A

                    \[\leadsto \log \color{blue}{\left(\frac{y}{-1 + x}\right)} + 1 \]
                  6. log-lowering-log.f64N/A

                    \[\leadsto \color{blue}{\log \left(\frac{y}{-1 + x}\right)} + 1 \]
                  7. /-lowering-/.f64N/A

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

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

                    \[\leadsto \log \left(\frac{y}{\color{blue}{x + -1}}\right) + 1 \]
                7. Applied egg-rr99.2%

                  \[\leadsto \color{blue}{\log \left(\frac{y}{x + -1}\right) + 1} \]
                8. Taylor expanded in x around 0

                  \[\leadsto \color{blue}{\log \left(-1 \cdot y\right)} + 1 \]
                9. Step-by-step derivation
                  1. log-lowering-log.f64N/A

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

                    \[\leadsto \log \color{blue}{\left(\mathsf{neg}\left(y\right)\right)} + 1 \]
                  3. neg-lowering-neg.f6477.6

                    \[\leadsto \log \color{blue}{\left(-y\right)} + 1 \]
                10. Simplified77.6%

                  \[\leadsto \color{blue}{\log \left(-y\right)} + 1 \]

                if -11.5 < y

                1. Initial program 96.4%

                  \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
                2. Add Preprocessing
                3. Taylor expanded in y around 0

                  \[\leadsto \color{blue}{\left(1 + -1 \cdot \left(y \cdot \left(-1 \cdot \frac{x}{1 - x} + \frac{1}{1 - x}\right)\right)\right) - \log \left(1 - x\right)} \]
                4. Step-by-step derivation
                  1. Simplified83.9%

                    \[\leadsto \color{blue}{\left(1 - y\right) - \mathsf{log1p}\left(-x\right)} \]
                5. Recombined 2 regimes into one program.
                6. Final simplification82.0%

                  \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -11.5:\\ \;\;\;\;1 + \log \left(-y\right)\\ \mathbf{else}:\\ \;\;\;\;\left(1 - y\right) - \mathsf{log1p}\left(-x\right)\\ \end{array} \]
                7. Add Preprocessing

                Alternative 13: 43.7% accurate, 31.0× speedup?

                \[\begin{array}{l} \\ x + 1 \end{array} \]
                (FPCore (x y) :precision binary64 (+ x 1.0))
                double code(double x, double y) {
                	return x + 1.0;
                }
                
                real(8) function code(x, y)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    code = x + 1.0d0
                end function
                
                public static double code(double x, double y) {
                	return x + 1.0;
                }
                
                def code(x, y):
                	return x + 1.0
                
                function code(x, y)
                	return Float64(x + 1.0)
                end
                
                function tmp = code(x, y)
                	tmp = x + 1.0;
                end
                
                code[x_, y_] := N[(x + 1.0), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                x + 1
                \end{array}
                
                Derivation
                1. Initial program 71.3%

                  \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
                2. Add Preprocessing
                3. Taylor expanded in y around 0

                  \[\leadsto 1 - \color{blue}{\log \left(1 - x\right)} \]
                4. Step-by-step derivation
                  1. sub-negN/A

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

                    \[\leadsto 1 - \log \left(1 + \color{blue}{-1 \cdot x}\right) \]
                  3. accelerator-lowering-log1p.f64N/A

                    \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-1 \cdot x\right)} \]
                  4. mul-1-negN/A

                    \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\mathsf{neg}\left(x\right)}\right) \]
                  5. neg-lowering-neg.f6461.2

                    \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{-x}\right) \]
                5. Simplified61.2%

                  \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-x\right)} \]
                6. Taylor expanded in x around 0

                  \[\leadsto \color{blue}{1 + x} \]
                7. Step-by-step derivation
                  1. +-lowering-+.f6441.4

                    \[\leadsto \color{blue}{1 + x} \]
                8. Simplified41.4%

                  \[\leadsto \color{blue}{1 + x} \]
                9. Final simplification41.4%

                  \[\leadsto x + 1 \]
                10. Add Preprocessing

                Alternative 14: 43.4% accurate, 124.0× speedup?

                \[\begin{array}{l} \\ 1 \end{array} \]
                (FPCore (x y) :precision binary64 1.0)
                double code(double x, double y) {
                	return 1.0;
                }
                
                real(8) function code(x, y)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    code = 1.0d0
                end function
                
                public static double code(double x, double y) {
                	return 1.0;
                }
                
                def code(x, y):
                	return 1.0
                
                function code(x, y)
                	return 1.0
                end
                
                function tmp = code(x, y)
                	tmp = 1.0;
                end
                
                code[x_, y_] := 1.0
                
                \begin{array}{l}
                
                \\
                1
                \end{array}
                
                Derivation
                1. Initial program 71.3%

                  \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
                2. Add Preprocessing
                3. Taylor expanded in y around 0

                  \[\leadsto 1 - \color{blue}{\log \left(1 - x\right)} \]
                4. Step-by-step derivation
                  1. sub-negN/A

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

                    \[\leadsto 1 - \log \left(1 + \color{blue}{-1 \cdot x}\right) \]
                  3. accelerator-lowering-log1p.f64N/A

                    \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-1 \cdot x\right)} \]
                  4. mul-1-negN/A

                    \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\mathsf{neg}\left(x\right)}\right) \]
                  5. neg-lowering-neg.f6461.2

                    \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{-x}\right) \]
                5. Simplified61.2%

                  \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-x\right)} \]
                6. Taylor expanded in x around 0

                  \[\leadsto \color{blue}{1} \]
                7. Step-by-step derivation
                  1. Simplified41.1%

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

                  Developer Target 1: 99.8% accurate, 0.5× speedup?

                  \[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 - \log \left(\frac{x}{y \cdot y} - \left(\frac{1}{y} - \frac{x}{y}\right)\right)\\ \mathbf{if}\;y < -81284752.61947241:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y < 3.0094271212461764 \cdot 10^{+25}:\\ \;\;\;\;\log \left(\frac{e^{1}}{1 - \frac{x - y}{1 - y}}\right)\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
                  (FPCore (x y)
                   :precision binary64
                   (let* ((t_0 (- 1.0 (log (- (/ x (* y y)) (- (/ 1.0 y) (/ x y)))))))
                     (if (< y -81284752.61947241)
                       t_0
                       (if (< y 3.0094271212461764e+25)
                         (log (/ (exp 1.0) (- 1.0 (/ (- x y) (- 1.0 y)))))
                         t_0))))
                  double code(double x, double y) {
                  	double t_0 = 1.0 - log(((x / (y * y)) - ((1.0 / y) - (x / y))));
                  	double tmp;
                  	if (y < -81284752.61947241) {
                  		tmp = t_0;
                  	} else if (y < 3.0094271212461764e+25) {
                  		tmp = log((exp(1.0) / (1.0 - ((x - y) / (1.0 - y)))));
                  	} 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 = 1.0d0 - log(((x / (y * y)) - ((1.0d0 / y) - (x / y))))
                      if (y < (-81284752.61947241d0)) then
                          tmp = t_0
                      else if (y < 3.0094271212461764d+25) then
                          tmp = log((exp(1.0d0) / (1.0d0 - ((x - y) / (1.0d0 - y)))))
                      else
                          tmp = t_0
                      end if
                      code = tmp
                  end function
                  
                  public static double code(double x, double y) {
                  	double t_0 = 1.0 - Math.log(((x / (y * y)) - ((1.0 / y) - (x / y))));
                  	double tmp;
                  	if (y < -81284752.61947241) {
                  		tmp = t_0;
                  	} else if (y < 3.0094271212461764e+25) {
                  		tmp = Math.log((Math.exp(1.0) / (1.0 - ((x - y) / (1.0 - y)))));
                  	} else {
                  		tmp = t_0;
                  	}
                  	return tmp;
                  }
                  
                  def code(x, y):
                  	t_0 = 1.0 - math.log(((x / (y * y)) - ((1.0 / y) - (x / y))))
                  	tmp = 0
                  	if y < -81284752.61947241:
                  		tmp = t_0
                  	elif y < 3.0094271212461764e+25:
                  		tmp = math.log((math.exp(1.0) / (1.0 - ((x - y) / (1.0 - y)))))
                  	else:
                  		tmp = t_0
                  	return tmp
                  
                  function code(x, y)
                  	t_0 = Float64(1.0 - log(Float64(Float64(x / Float64(y * y)) - Float64(Float64(1.0 / y) - Float64(x / y)))))
                  	tmp = 0.0
                  	if (y < -81284752.61947241)
                  		tmp = t_0;
                  	elseif (y < 3.0094271212461764e+25)
                  		tmp = log(Float64(exp(1.0) / Float64(1.0 - Float64(Float64(x - y) / Float64(1.0 - y)))));
                  	else
                  		tmp = t_0;
                  	end
                  	return tmp
                  end
                  
                  function tmp_2 = code(x, y)
                  	t_0 = 1.0 - log(((x / (y * y)) - ((1.0 / y) - (x / y))));
                  	tmp = 0.0;
                  	if (y < -81284752.61947241)
                  		tmp = t_0;
                  	elseif (y < 3.0094271212461764e+25)
                  		tmp = log((exp(1.0) / (1.0 - ((x - y) / (1.0 - y)))));
                  	else
                  		tmp = t_0;
                  	end
                  	tmp_2 = tmp;
                  end
                  
                  code[x_, y_] := Block[{t$95$0 = N[(1.0 - N[Log[N[(N[(x / N[(y * y), $MachinePrecision]), $MachinePrecision] - N[(N[(1.0 / y), $MachinePrecision] - N[(x / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[Less[y, -81284752.61947241], t$95$0, If[Less[y, 3.0094271212461764e+25], N[Log[N[(N[Exp[1.0], $MachinePrecision] / N[(1.0 - N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], t$95$0]]]
                  
                  \begin{array}{l}
                  
                  \\
                  \begin{array}{l}
                  t_0 := 1 - \log \left(\frac{x}{y \cdot y} - \left(\frac{1}{y} - \frac{x}{y}\right)\right)\\
                  \mathbf{if}\;y < -81284752.61947241:\\
                  \;\;\;\;t\_0\\
                  
                  \mathbf{elif}\;y < 3.0094271212461764 \cdot 10^{+25}:\\
                  \;\;\;\;\log \left(\frac{e^{1}}{1 - \frac{x - y}{1 - y}}\right)\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;t\_0\\
                  
                  
                  \end{array}
                  \end{array}
                  

                  Reproduce

                  ?
                  herbie shell --seed 2024204 
                  (FPCore (x y)
                    :name "Numeric.SpecFunctions:invIncompleteGamma from math-functions-0.1.5.2, B"
                    :precision binary64
                  
                    :alt
                    (! :herbie-platform default (if (< y -8128475261947241/100000000) (- 1 (log (- (/ x (* y y)) (- (/ 1 y) (/ x y))))) (if (< y 30094271212461764000000000) (log (/ (exp 1) (- 1 (/ (- x y) (- 1 y))))) (- 1 (log (- (/ x (* y y)) (- (/ 1 y) (/ x y))))))))
                  
                    (- 1.0 (log (- 1.0 (/ (- x y) (- 1.0 y))))))