Diagrams.Trail:splitAtParam from diagrams-lib-1.3.0.3, C

Percentage Accurate: 100.0% → 100.0%
Time: 5.2s
Alternatives: 9
Speedup: 1.0×

Specification

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

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

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 9 alternatives:

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

Initial Program: 100.0% accurate, 1.0× speedup?

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

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

Alternative 1: 100.0% accurate, 1.0× speedup?

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

\\
\frac{x - y}{1 - y}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{x - y}{1 - y} \]
  2. Final simplification100.0%

    \[\leadsto \frac{x - y}{1 - y} \]

Alternative 2: 73.2% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{-x}{y}\\ \mathbf{if}\;y \leq -2.4 \cdot 10^{+71}:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq -5.2 \cdot 10^{+52}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq -1:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq -1.02 \cdot 10^{-63}:\\ \;\;\;\;-y\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;x\\ \mathbf{elif}\;y \leq 1.65 \cdot 10^{+50}:\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (/ (- x) y)))
   (if (<= y -2.4e+71)
     1.0
     (if (<= y -5.2e+52)
       t_0
       (if (<= y -1.0)
         1.0
         (if (<= y -1.02e-63)
           (- y)
           (if (<= y 1.0) x (if (<= y 1.65e+50) t_0 1.0))))))))
double code(double x, double y) {
	double t_0 = -x / y;
	double tmp;
	if (y <= -2.4e+71) {
		tmp = 1.0;
	} else if (y <= -5.2e+52) {
		tmp = t_0;
	} else if (y <= -1.0) {
		tmp = 1.0;
	} else if (y <= -1.02e-63) {
		tmp = -y;
	} else if (y <= 1.0) {
		tmp = x;
	} else if (y <= 1.65e+50) {
		tmp = t_0;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: t_0
    real(8) :: tmp
    t_0 = -x / y
    if (y <= (-2.4d+71)) then
        tmp = 1.0d0
    else if (y <= (-5.2d+52)) then
        tmp = t_0
    else if (y <= (-1.0d0)) then
        tmp = 1.0d0
    else if (y <= (-1.02d-63)) then
        tmp = -y
    else if (y <= 1.0d0) then
        tmp = x
    else if (y <= 1.65d+50) then
        tmp = t_0
    else
        tmp = 1.0d0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double t_0 = -x / y;
	double tmp;
	if (y <= -2.4e+71) {
		tmp = 1.0;
	} else if (y <= -5.2e+52) {
		tmp = t_0;
	} else if (y <= -1.0) {
		tmp = 1.0;
	} else if (y <= -1.02e-63) {
		tmp = -y;
	} else if (y <= 1.0) {
		tmp = x;
	} else if (y <= 1.65e+50) {
		tmp = t_0;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
def code(x, y):
	t_0 = -x / y
	tmp = 0
	if y <= -2.4e+71:
		tmp = 1.0
	elif y <= -5.2e+52:
		tmp = t_0
	elif y <= -1.0:
		tmp = 1.0
	elif y <= -1.02e-63:
		tmp = -y
	elif y <= 1.0:
		tmp = x
	elif y <= 1.65e+50:
		tmp = t_0
	else:
		tmp = 1.0
	return tmp
function code(x, y)
	t_0 = Float64(Float64(-x) / y)
	tmp = 0.0
	if (y <= -2.4e+71)
		tmp = 1.0;
	elseif (y <= -5.2e+52)
		tmp = t_0;
	elseif (y <= -1.0)
		tmp = 1.0;
	elseif (y <= -1.02e-63)
		tmp = Float64(-y);
	elseif (y <= 1.0)
		tmp = x;
	elseif (y <= 1.65e+50)
		tmp = t_0;
	else
		tmp = 1.0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = -x / y;
	tmp = 0.0;
	if (y <= -2.4e+71)
		tmp = 1.0;
	elseif (y <= -5.2e+52)
		tmp = t_0;
	elseif (y <= -1.0)
		tmp = 1.0;
	elseif (y <= -1.02e-63)
		tmp = -y;
	elseif (y <= 1.0)
		tmp = x;
	elseif (y <= 1.65e+50)
		tmp = t_0;
	else
		tmp = 1.0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[((-x) / y), $MachinePrecision]}, If[LessEqual[y, -2.4e+71], 1.0, If[LessEqual[y, -5.2e+52], t$95$0, If[LessEqual[y, -1.0], 1.0, If[LessEqual[y, -1.02e-63], (-y), If[LessEqual[y, 1.0], x, If[LessEqual[y, 1.65e+50], t$95$0, 1.0]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{-x}{y}\\
\mathbf{if}\;y \leq -2.4 \cdot 10^{+71}:\\
\;\;\;\;1\\

\mathbf{elif}\;y \leq -5.2 \cdot 10^{+52}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;y \leq -1:\\
\;\;\;\;1\\

\mathbf{elif}\;y \leq -1.02 \cdot 10^{-63}:\\
\;\;\;\;-y\\

\mathbf{elif}\;y \leq 1:\\
\;\;\;\;x\\

\mathbf{elif}\;y \leq 1.65 \cdot 10^{+50}:\\
\;\;\;\;t_0\\

\mathbf{else}:\\
\;\;\;\;1\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if y < -2.39999999999999981e71 or -5.2e52 < y < -1 or 1.65e50 < y

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around inf 83.6%

      \[\leadsto \color{blue}{1} \]

    if -2.39999999999999981e71 < y < -5.2e52 or 1 < y < 1.65e50

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around inf 84.6%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y - 1}} \]
    5. Step-by-step derivation
      1. sub-neg84.6%

        \[\leadsto -1 \cdot \frac{x}{\color{blue}{y + \left(-1\right)}} \]
      2. metadata-eval84.6%

        \[\leadsto -1 \cdot \frac{x}{y + \color{blue}{-1}} \]
      3. neg-mul-184.6%

        \[\leadsto \color{blue}{-\frac{x}{y + -1}} \]
      4. distribute-neg-frac84.6%

        \[\leadsto \color{blue}{\frac{-x}{y + -1}} \]
      5. +-commutative84.6%

        \[\leadsto \frac{-x}{\color{blue}{-1 + y}} \]
    6. Simplified84.6%

      \[\leadsto \color{blue}{\frac{-x}{-1 + y}} \]
    7. Step-by-step derivation
      1. frac-2neg84.6%

        \[\leadsto \color{blue}{\frac{-\left(-x\right)}{-\left(-1 + y\right)}} \]
      2. +-commutative84.6%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y + -1\right)}} \]
      3. metadata-eval84.6%

        \[\leadsto \frac{-\left(-x\right)}{-\left(y + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg84.6%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y - 1\right)}} \]
      5. div-inv84.4%

        \[\leadsto \color{blue}{\left(-\left(-x\right)\right) \cdot \frac{1}{-\left(y - 1\right)}} \]
      6. remove-double-neg84.4%

        \[\leadsto \color{blue}{x} \cdot \frac{1}{-\left(y - 1\right)} \]
      7. sub-neg84.4%

        \[\leadsto x \cdot \frac{1}{-\color{blue}{\left(y + \left(-1\right)\right)}} \]
      8. metadata-eval84.4%

        \[\leadsto x \cdot \frac{1}{-\left(y + \color{blue}{-1}\right)} \]
      9. distribute-neg-in84.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\left(-y\right) + \left(--1\right)}} \]
      10. neg-mul-184.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{-1 \cdot y} + \left(--1\right)} \]
      11. *-commutative84.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{y \cdot -1} + \left(--1\right)} \]
      12. metadata-eval84.4%

        \[\leadsto x \cdot \frac{1}{y \cdot -1 + \color{blue}{1}} \]
      13. fma-def84.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    8. Applied egg-rr84.4%

      \[\leadsto \color{blue}{x \cdot \frac{1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    9. Step-by-step derivation
      1. associate-*r/84.6%

        \[\leadsto \color{blue}{\frac{x \cdot 1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
      2. *-rgt-identity84.6%

        \[\leadsto \frac{\color{blue}{x}}{\mathsf{fma}\left(y, -1, 1\right)} \]
      3. fma-udef84.6%

        \[\leadsto \frac{x}{\color{blue}{y \cdot -1 + 1}} \]
      4. *-commutative84.6%

        \[\leadsto \frac{x}{\color{blue}{-1 \cdot y} + 1} \]
      5. neg-mul-184.6%

        \[\leadsto \frac{x}{\color{blue}{\left(-y\right)} + 1} \]
      6. +-commutative84.6%

        \[\leadsto \frac{x}{\color{blue}{1 + \left(-y\right)}} \]
      7. unsub-neg84.6%

        \[\leadsto \frac{x}{\color{blue}{1 - y}} \]
    10. Simplified84.6%

      \[\leadsto \color{blue}{\frac{x}{1 - y}} \]
    11. Taylor expanded in y around inf 79.3%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y}} \]
    12. Step-by-step derivation
      1. associate-*r/79.3%

        \[\leadsto \color{blue}{\frac{-1 \cdot x}{y}} \]
      2. neg-mul-179.3%

        \[\leadsto \frac{\color{blue}{-x}}{y} \]
    13. Simplified79.3%

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

    if -1 < y < -1.01999999999999997e-63

    1. Initial program 99.8%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg99.8%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative99.8%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub099.8%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-99.8%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg99.8%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-199.8%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub099.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-199.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac99.8%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval99.8%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity99.8%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg99.8%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval99.8%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around 0 62.4%

      \[\leadsto \color{blue}{\frac{y}{y - 1}} \]
    5. Taylor expanded in y around 0 54.3%

      \[\leadsto \color{blue}{-1 \cdot y} \]
    6. Step-by-step derivation
      1. neg-mul-154.3%

        \[\leadsto \color{blue}{-y} \]
    7. Simplified54.3%

      \[\leadsto \color{blue}{-y} \]

    if -1.01999999999999997e-63 < y < 1

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around 0 82.1%

      \[\leadsto \color{blue}{x} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification80.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -2.4 \cdot 10^{+71}:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq -5.2 \cdot 10^{+52}:\\ \;\;\;\;\frac{-x}{y}\\ \mathbf{elif}\;y \leq -1:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq -1.02 \cdot 10^{-63}:\\ \;\;\;\;-y\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;x\\ \mathbf{elif}\;y \leq 1.65 \cdot 10^{+50}:\\ \;\;\;\;\frac{-x}{y}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]

Alternative 3: 74.1% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -4 \cdot 10^{+71}:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq -2.85 \cdot 10^{+51}:\\ \;\;\;\;\frac{-x}{y}\\ \mathbf{elif}\;y \leq -1 \cdot 10^{-63} \lor \neg \left(y \leq 1.8 \cdot 10^{+50}\right):\\ \;\;\;\;\frac{y}{y + -1}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{1 - y}\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -4e+71)
   1.0
   (if (<= y -2.85e+51)
     (/ (- x) y)
     (if (or (<= y -1e-63) (not (<= y 1.8e+50)))
       (/ y (+ y -1.0))
       (/ x (- 1.0 y))))))
double code(double x, double y) {
	double tmp;
	if (y <= -4e+71) {
		tmp = 1.0;
	} else if (y <= -2.85e+51) {
		tmp = -x / y;
	} else if ((y <= -1e-63) || !(y <= 1.8e+50)) {
		tmp = y / (y + -1.0);
	} else {
		tmp = x / (1.0 - y);
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= (-4d+71)) then
        tmp = 1.0d0
    else if (y <= (-2.85d+51)) then
        tmp = -x / y
    else if ((y <= (-1d-63)) .or. (.not. (y <= 1.8d+50))) then
        tmp = y / (y + (-1.0d0))
    else
        tmp = x / (1.0d0 - y)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -4e+71) {
		tmp = 1.0;
	} else if (y <= -2.85e+51) {
		tmp = -x / y;
	} else if ((y <= -1e-63) || !(y <= 1.8e+50)) {
		tmp = y / (y + -1.0);
	} else {
		tmp = x / (1.0 - y);
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -4e+71:
		tmp = 1.0
	elif y <= -2.85e+51:
		tmp = -x / y
	elif (y <= -1e-63) or not (y <= 1.8e+50):
		tmp = y / (y + -1.0)
	else:
		tmp = x / (1.0 - y)
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -4e+71)
		tmp = 1.0;
	elseif (y <= -2.85e+51)
		tmp = Float64(Float64(-x) / y);
	elseif ((y <= -1e-63) || !(y <= 1.8e+50))
		tmp = Float64(y / Float64(y + -1.0));
	else
		tmp = Float64(x / Float64(1.0 - y));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -4e+71)
		tmp = 1.0;
	elseif (y <= -2.85e+51)
		tmp = -x / y;
	elseif ((y <= -1e-63) || ~((y <= 1.8e+50)))
		tmp = y / (y + -1.0);
	else
		tmp = x / (1.0 - y);
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -4e+71], 1.0, If[LessEqual[y, -2.85e+51], N[((-x) / y), $MachinePrecision], If[Or[LessEqual[y, -1e-63], N[Not[LessEqual[y, 1.8e+50]], $MachinePrecision]], N[(y / N[(y + -1.0), $MachinePrecision]), $MachinePrecision], N[(x / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -4 \cdot 10^{+71}:\\
\;\;\;\;1\\

\mathbf{elif}\;y \leq -2.85 \cdot 10^{+51}:\\
\;\;\;\;\frac{-x}{y}\\

\mathbf{elif}\;y \leq -1 \cdot 10^{-63} \lor \neg \left(y \leq 1.8 \cdot 10^{+50}\right):\\
\;\;\;\;\frac{y}{y + -1}\\

\mathbf{else}:\\
\;\;\;\;\frac{x}{1 - y}\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if y < -4.0000000000000002e71

    1. Initial program 99.9%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg99.9%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative99.9%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub099.9%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-99.9%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg99.9%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-199.9%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub099.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-199.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac99.9%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval99.9%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity99.9%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg99.9%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval99.9%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around inf 82.2%

      \[\leadsto \color{blue}{1} \]

    if -4.0000000000000002e71 < y < -2.8500000000000001e51

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around inf 90.4%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y - 1}} \]
    5. Step-by-step derivation
      1. sub-neg90.4%

        \[\leadsto -1 \cdot \frac{x}{\color{blue}{y + \left(-1\right)}} \]
      2. metadata-eval90.4%

        \[\leadsto -1 \cdot \frac{x}{y + \color{blue}{-1}} \]
      3. neg-mul-190.4%

        \[\leadsto \color{blue}{-\frac{x}{y + -1}} \]
      4. distribute-neg-frac90.4%

        \[\leadsto \color{blue}{\frac{-x}{y + -1}} \]
      5. +-commutative90.4%

        \[\leadsto \frac{-x}{\color{blue}{-1 + y}} \]
    6. Simplified90.4%

      \[\leadsto \color{blue}{\frac{-x}{-1 + y}} \]
    7. Step-by-step derivation
      1. frac-2neg90.4%

        \[\leadsto \color{blue}{\frac{-\left(-x\right)}{-\left(-1 + y\right)}} \]
      2. +-commutative90.4%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y + -1\right)}} \]
      3. metadata-eval90.4%

        \[\leadsto \frac{-\left(-x\right)}{-\left(y + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg90.4%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y - 1\right)}} \]
      5. div-inv90.4%

        \[\leadsto \color{blue}{\left(-\left(-x\right)\right) \cdot \frac{1}{-\left(y - 1\right)}} \]
      6. remove-double-neg90.4%

        \[\leadsto \color{blue}{x} \cdot \frac{1}{-\left(y - 1\right)} \]
      7. sub-neg90.4%

        \[\leadsto x \cdot \frac{1}{-\color{blue}{\left(y + \left(-1\right)\right)}} \]
      8. metadata-eval90.4%

        \[\leadsto x \cdot \frac{1}{-\left(y + \color{blue}{-1}\right)} \]
      9. distribute-neg-in90.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\left(-y\right) + \left(--1\right)}} \]
      10. neg-mul-190.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{-1 \cdot y} + \left(--1\right)} \]
      11. *-commutative90.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{y \cdot -1} + \left(--1\right)} \]
      12. metadata-eval90.4%

        \[\leadsto x \cdot \frac{1}{y \cdot -1 + \color{blue}{1}} \]
      13. fma-def90.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    8. Applied egg-rr90.4%

      \[\leadsto \color{blue}{x \cdot \frac{1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    9. Step-by-step derivation
      1. associate-*r/90.4%

        \[\leadsto \color{blue}{\frac{x \cdot 1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
      2. *-rgt-identity90.4%

        \[\leadsto \frac{\color{blue}{x}}{\mathsf{fma}\left(y, -1, 1\right)} \]
      3. fma-udef90.4%

        \[\leadsto \frac{x}{\color{blue}{y \cdot -1 + 1}} \]
      4. *-commutative90.4%

        \[\leadsto \frac{x}{\color{blue}{-1 \cdot y} + 1} \]
      5. neg-mul-190.4%

        \[\leadsto \frac{x}{\color{blue}{\left(-y\right)} + 1} \]
      6. +-commutative90.4%

        \[\leadsto \frac{x}{\color{blue}{1 + \left(-y\right)}} \]
      7. unsub-neg90.4%

        \[\leadsto \frac{x}{\color{blue}{1 - y}} \]
    10. Simplified90.4%

      \[\leadsto \color{blue}{\frac{x}{1 - y}} \]
    11. Taylor expanded in y around inf 90.4%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y}} \]
    12. Step-by-step derivation
      1. associate-*r/90.4%

        \[\leadsto \color{blue}{\frac{-1 \cdot x}{y}} \]
      2. neg-mul-190.4%

        \[\leadsto \frac{\color{blue}{-x}}{y} \]
    13. Simplified90.4%

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

    if -2.8500000000000001e51 < y < -1.00000000000000007e-63 or 1.79999999999999993e50 < y

    1. Initial program 99.9%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg99.9%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative99.9%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub099.9%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-99.9%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg99.9%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-199.9%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub099.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-199.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac99.9%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval99.9%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity99.9%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg99.9%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval99.9%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around 0 80.2%

      \[\leadsto \color{blue}{\frac{y}{y - 1}} \]

    if -1.00000000000000007e-63 < y < 1.79999999999999993e50

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around inf 83.1%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y - 1}} \]
    5. Step-by-step derivation
      1. sub-neg83.1%

        \[\leadsto -1 \cdot \frac{x}{\color{blue}{y + \left(-1\right)}} \]
      2. metadata-eval83.1%

        \[\leadsto -1 \cdot \frac{x}{y + \color{blue}{-1}} \]
      3. neg-mul-183.1%

        \[\leadsto \color{blue}{-\frac{x}{y + -1}} \]
      4. distribute-neg-frac83.1%

        \[\leadsto \color{blue}{\frac{-x}{y + -1}} \]
      5. +-commutative83.1%

        \[\leadsto \frac{-x}{\color{blue}{-1 + y}} \]
    6. Simplified83.1%

      \[\leadsto \color{blue}{\frac{-x}{-1 + y}} \]
    7. Step-by-step derivation
      1. frac-2neg83.1%

        \[\leadsto \color{blue}{\frac{-\left(-x\right)}{-\left(-1 + y\right)}} \]
      2. +-commutative83.1%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y + -1\right)}} \]
      3. metadata-eval83.1%

        \[\leadsto \frac{-\left(-x\right)}{-\left(y + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg83.1%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y - 1\right)}} \]
      5. div-inv83.0%

        \[\leadsto \color{blue}{\left(-\left(-x\right)\right) \cdot \frac{1}{-\left(y - 1\right)}} \]
      6. remove-double-neg83.0%

        \[\leadsto \color{blue}{x} \cdot \frac{1}{-\left(y - 1\right)} \]
      7. sub-neg83.0%

        \[\leadsto x \cdot \frac{1}{-\color{blue}{\left(y + \left(-1\right)\right)}} \]
      8. metadata-eval83.0%

        \[\leadsto x \cdot \frac{1}{-\left(y + \color{blue}{-1}\right)} \]
      9. distribute-neg-in83.0%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\left(-y\right) + \left(--1\right)}} \]
      10. neg-mul-183.0%

        \[\leadsto x \cdot \frac{1}{\color{blue}{-1 \cdot y} + \left(--1\right)} \]
      11. *-commutative83.0%

        \[\leadsto x \cdot \frac{1}{\color{blue}{y \cdot -1} + \left(--1\right)} \]
      12. metadata-eval83.0%

        \[\leadsto x \cdot \frac{1}{y \cdot -1 + \color{blue}{1}} \]
      13. fma-def83.0%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    8. Applied egg-rr83.0%

      \[\leadsto \color{blue}{x \cdot \frac{1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    9. Step-by-step derivation
      1. associate-*r/83.1%

        \[\leadsto \color{blue}{\frac{x \cdot 1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
      2. *-rgt-identity83.1%

        \[\leadsto \frac{\color{blue}{x}}{\mathsf{fma}\left(y, -1, 1\right)} \]
      3. fma-udef83.1%

        \[\leadsto \frac{x}{\color{blue}{y \cdot -1 + 1}} \]
      4. *-commutative83.1%

        \[\leadsto \frac{x}{\color{blue}{-1 \cdot y} + 1} \]
      5. neg-mul-183.1%

        \[\leadsto \frac{x}{\color{blue}{\left(-y\right)} + 1} \]
      6. +-commutative83.1%

        \[\leadsto \frac{x}{\color{blue}{1 + \left(-y\right)}} \]
      7. unsub-neg83.1%

        \[\leadsto \frac{x}{\color{blue}{1 - y}} \]
    10. Simplified83.1%

      \[\leadsto \color{blue}{\frac{x}{1 - y}} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification82.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -4 \cdot 10^{+71}:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq -2.85 \cdot 10^{+51}:\\ \;\;\;\;\frac{-x}{y}\\ \mathbf{elif}\;y \leq -1 \cdot 10^{-63} \lor \neg \left(y \leq 1.8 \cdot 10^{+50}\right):\\ \;\;\;\;\frac{y}{y + -1}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{1 - y}\\ \end{array} \]

Alternative 4: 74.5% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -2.7 \cdot 10^{+72}:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq -3 \cdot 10^{+53}:\\ \;\;\;\;\frac{-x}{y}\\ \mathbf{elif}\;y \leq -0.0023:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq 2.2 \cdot 10^{+50}:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -2.7e+72)
   1.0
   (if (<= y -3e+53)
     (/ (- x) y)
     (if (<= y -0.0023) 1.0 (if (<= y 2.2e+50) (/ x (- 1.0 y)) 1.0)))))
double code(double x, double y) {
	double tmp;
	if (y <= -2.7e+72) {
		tmp = 1.0;
	} else if (y <= -3e+53) {
		tmp = -x / y;
	} else if (y <= -0.0023) {
		tmp = 1.0;
	} else if (y <= 2.2e+50) {
		tmp = x / (1.0 - y);
	} else {
		tmp = 1.0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= (-2.7d+72)) then
        tmp = 1.0d0
    else if (y <= (-3d+53)) then
        tmp = -x / y
    else if (y <= (-0.0023d0)) then
        tmp = 1.0d0
    else if (y <= 2.2d+50) then
        tmp = x / (1.0d0 - y)
    else
        tmp = 1.0d0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -2.7e+72) {
		tmp = 1.0;
	} else if (y <= -3e+53) {
		tmp = -x / y;
	} else if (y <= -0.0023) {
		tmp = 1.0;
	} else if (y <= 2.2e+50) {
		tmp = x / (1.0 - y);
	} else {
		tmp = 1.0;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -2.7e+72:
		tmp = 1.0
	elif y <= -3e+53:
		tmp = -x / y
	elif y <= -0.0023:
		tmp = 1.0
	elif y <= 2.2e+50:
		tmp = x / (1.0 - y)
	else:
		tmp = 1.0
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -2.7e+72)
		tmp = 1.0;
	elseif (y <= -3e+53)
		tmp = Float64(Float64(-x) / y);
	elseif (y <= -0.0023)
		tmp = 1.0;
	elseif (y <= 2.2e+50)
		tmp = Float64(x / Float64(1.0 - y));
	else
		tmp = 1.0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -2.7e+72)
		tmp = 1.0;
	elseif (y <= -3e+53)
		tmp = -x / y;
	elseif (y <= -0.0023)
		tmp = 1.0;
	elseif (y <= 2.2e+50)
		tmp = x / (1.0 - y);
	else
		tmp = 1.0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -2.7e+72], 1.0, If[LessEqual[y, -3e+53], N[((-x) / y), $MachinePrecision], If[LessEqual[y, -0.0023], 1.0, If[LessEqual[y, 2.2e+50], N[(x / N[(1.0 - y), $MachinePrecision]), $MachinePrecision], 1.0]]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -2.7 \cdot 10^{+72}:\\
\;\;\;\;1\\

\mathbf{elif}\;y \leq -3 \cdot 10^{+53}:\\
\;\;\;\;\frac{-x}{y}\\

\mathbf{elif}\;y \leq -0.0023:\\
\;\;\;\;1\\

\mathbf{elif}\;y \leq 2.2 \cdot 10^{+50}:\\
\;\;\;\;\frac{x}{1 - y}\\

\mathbf{else}:\\
\;\;\;\;1\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < -2.7000000000000001e72 or -2.99999999999999998e53 < y < -0.0023 or 2.20000000000000017e50 < y

    1. Initial program 99.9%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg99.9%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative99.9%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub099.9%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-99.9%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg99.9%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-199.9%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub099.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg99.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-199.9%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac99.9%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval99.9%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity99.9%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg99.9%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval99.9%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around inf 82.4%

      \[\leadsto \color{blue}{1} \]

    if -2.7000000000000001e72 < y < -2.99999999999999998e53

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around inf 90.4%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y - 1}} \]
    5. Step-by-step derivation
      1. sub-neg90.4%

        \[\leadsto -1 \cdot \frac{x}{\color{blue}{y + \left(-1\right)}} \]
      2. metadata-eval90.4%

        \[\leadsto -1 \cdot \frac{x}{y + \color{blue}{-1}} \]
      3. neg-mul-190.4%

        \[\leadsto \color{blue}{-\frac{x}{y + -1}} \]
      4. distribute-neg-frac90.4%

        \[\leadsto \color{blue}{\frac{-x}{y + -1}} \]
      5. +-commutative90.4%

        \[\leadsto \frac{-x}{\color{blue}{-1 + y}} \]
    6. Simplified90.4%

      \[\leadsto \color{blue}{\frac{-x}{-1 + y}} \]
    7. Step-by-step derivation
      1. frac-2neg90.4%

        \[\leadsto \color{blue}{\frac{-\left(-x\right)}{-\left(-1 + y\right)}} \]
      2. +-commutative90.4%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y + -1\right)}} \]
      3. metadata-eval90.4%

        \[\leadsto \frac{-\left(-x\right)}{-\left(y + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg90.4%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y - 1\right)}} \]
      5. div-inv90.4%

        \[\leadsto \color{blue}{\left(-\left(-x\right)\right) \cdot \frac{1}{-\left(y - 1\right)}} \]
      6. remove-double-neg90.4%

        \[\leadsto \color{blue}{x} \cdot \frac{1}{-\left(y - 1\right)} \]
      7. sub-neg90.4%

        \[\leadsto x \cdot \frac{1}{-\color{blue}{\left(y + \left(-1\right)\right)}} \]
      8. metadata-eval90.4%

        \[\leadsto x \cdot \frac{1}{-\left(y + \color{blue}{-1}\right)} \]
      9. distribute-neg-in90.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\left(-y\right) + \left(--1\right)}} \]
      10. neg-mul-190.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{-1 \cdot y} + \left(--1\right)} \]
      11. *-commutative90.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{y \cdot -1} + \left(--1\right)} \]
      12. metadata-eval90.4%

        \[\leadsto x \cdot \frac{1}{y \cdot -1 + \color{blue}{1}} \]
      13. fma-def90.4%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    8. Applied egg-rr90.4%

      \[\leadsto \color{blue}{x \cdot \frac{1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    9. Step-by-step derivation
      1. associate-*r/90.4%

        \[\leadsto \color{blue}{\frac{x \cdot 1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
      2. *-rgt-identity90.4%

        \[\leadsto \frac{\color{blue}{x}}{\mathsf{fma}\left(y, -1, 1\right)} \]
      3. fma-udef90.4%

        \[\leadsto \frac{x}{\color{blue}{y \cdot -1 + 1}} \]
      4. *-commutative90.4%

        \[\leadsto \frac{x}{\color{blue}{-1 \cdot y} + 1} \]
      5. neg-mul-190.4%

        \[\leadsto \frac{x}{\color{blue}{\left(-y\right)} + 1} \]
      6. +-commutative90.4%

        \[\leadsto \frac{x}{\color{blue}{1 + \left(-y\right)}} \]
      7. unsub-neg90.4%

        \[\leadsto \frac{x}{\color{blue}{1 - y}} \]
    10. Simplified90.4%

      \[\leadsto \color{blue}{\frac{x}{1 - y}} \]
    11. Taylor expanded in y around inf 90.4%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y}} \]
    12. Step-by-step derivation
      1. associate-*r/90.4%

        \[\leadsto \color{blue}{\frac{-1 \cdot x}{y}} \]
      2. neg-mul-190.4%

        \[\leadsto \frac{\color{blue}{-x}}{y} \]
    13. Simplified90.4%

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

    if -0.0023 < y < 2.20000000000000017e50

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around inf 78.1%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y - 1}} \]
    5. Step-by-step derivation
      1. sub-neg78.1%

        \[\leadsto -1 \cdot \frac{x}{\color{blue}{y + \left(-1\right)}} \]
      2. metadata-eval78.1%

        \[\leadsto -1 \cdot \frac{x}{y + \color{blue}{-1}} \]
      3. neg-mul-178.1%

        \[\leadsto \color{blue}{-\frac{x}{y + -1}} \]
      4. distribute-neg-frac78.1%

        \[\leadsto \color{blue}{\frac{-x}{y + -1}} \]
      5. +-commutative78.1%

        \[\leadsto \frac{-x}{\color{blue}{-1 + y}} \]
    6. Simplified78.1%

      \[\leadsto \color{blue}{\frac{-x}{-1 + y}} \]
    7. Step-by-step derivation
      1. frac-2neg78.1%

        \[\leadsto \color{blue}{\frac{-\left(-x\right)}{-\left(-1 + y\right)}} \]
      2. +-commutative78.1%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y + -1\right)}} \]
      3. metadata-eval78.1%

        \[\leadsto \frac{-\left(-x\right)}{-\left(y + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg78.1%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y - 1\right)}} \]
      5. div-inv78.0%

        \[\leadsto \color{blue}{\left(-\left(-x\right)\right) \cdot \frac{1}{-\left(y - 1\right)}} \]
      6. remove-double-neg78.0%

        \[\leadsto \color{blue}{x} \cdot \frac{1}{-\left(y - 1\right)} \]
      7. sub-neg78.0%

        \[\leadsto x \cdot \frac{1}{-\color{blue}{\left(y + \left(-1\right)\right)}} \]
      8. metadata-eval78.0%

        \[\leadsto x \cdot \frac{1}{-\left(y + \color{blue}{-1}\right)} \]
      9. distribute-neg-in78.0%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\left(-y\right) + \left(--1\right)}} \]
      10. neg-mul-178.0%

        \[\leadsto x \cdot \frac{1}{\color{blue}{-1 \cdot y} + \left(--1\right)} \]
      11. *-commutative78.0%

        \[\leadsto x \cdot \frac{1}{\color{blue}{y \cdot -1} + \left(--1\right)} \]
      12. metadata-eval78.0%

        \[\leadsto x \cdot \frac{1}{y \cdot -1 + \color{blue}{1}} \]
      13. fma-def78.0%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    8. Applied egg-rr78.0%

      \[\leadsto \color{blue}{x \cdot \frac{1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    9. Step-by-step derivation
      1. associate-*r/78.1%

        \[\leadsto \color{blue}{\frac{x \cdot 1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
      2. *-rgt-identity78.1%

        \[\leadsto \frac{\color{blue}{x}}{\mathsf{fma}\left(y, -1, 1\right)} \]
      3. fma-udef78.1%

        \[\leadsto \frac{x}{\color{blue}{y \cdot -1 + 1}} \]
      4. *-commutative78.1%

        \[\leadsto \frac{x}{\color{blue}{-1 \cdot y} + 1} \]
      5. neg-mul-178.1%

        \[\leadsto \frac{x}{\color{blue}{\left(-y\right)} + 1} \]
      6. +-commutative78.1%

        \[\leadsto \frac{x}{\color{blue}{1 + \left(-y\right)}} \]
      7. unsub-neg78.1%

        \[\leadsto \frac{x}{\color{blue}{1 - y}} \]
    10. Simplified78.1%

      \[\leadsto \color{blue}{\frac{x}{1 - y}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification80.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -2.7 \cdot 10^{+72}:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq -3 \cdot 10^{+53}:\\ \;\;\;\;\frac{-x}{y}\\ \mathbf{elif}\;y \leq -0.0023:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq 2.2 \cdot 10^{+50}:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]

Alternative 5: 86.0% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + \frac{1 - x}{y}\\ \mathbf{if}\;y \leq -11000:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq -1.05 \cdot 10^{-63}:\\ \;\;\;\;y \cdot \frac{1}{y + -1}\\ \mathbf{elif}\;y \leq 10000000000000:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (+ 1.0 (/ (- 1.0 x) y))))
   (if (<= y -11000.0)
     t_0
     (if (<= y -1.05e-63)
       (* y (/ 1.0 (+ y -1.0)))
       (if (<= y 10000000000000.0) (/ x (- 1.0 y)) t_0)))))
double code(double x, double y) {
	double t_0 = 1.0 + ((1.0 - x) / y);
	double tmp;
	if (y <= -11000.0) {
		tmp = t_0;
	} else if (y <= -1.05e-63) {
		tmp = y * (1.0 / (y + -1.0));
	} else if (y <= 10000000000000.0) {
		tmp = x / (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 + ((1.0d0 - x) / y)
    if (y <= (-11000.0d0)) then
        tmp = t_0
    else if (y <= (-1.05d-63)) then
        tmp = y * (1.0d0 / (y + (-1.0d0)))
    else if (y <= 10000000000000.0d0) then
        tmp = x / (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 + ((1.0 - x) / y);
	double tmp;
	if (y <= -11000.0) {
		tmp = t_0;
	} else if (y <= -1.05e-63) {
		tmp = y * (1.0 / (y + -1.0));
	} else if (y <= 10000000000000.0) {
		tmp = x / (1.0 - y);
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 1.0 + ((1.0 - x) / y)
	tmp = 0
	if y <= -11000.0:
		tmp = t_0
	elif y <= -1.05e-63:
		tmp = y * (1.0 / (y + -1.0))
	elif y <= 10000000000000.0:
		tmp = x / (1.0 - y)
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(1.0 + Float64(Float64(1.0 - x) / y))
	tmp = 0.0
	if (y <= -11000.0)
		tmp = t_0;
	elseif (y <= -1.05e-63)
		tmp = Float64(y * Float64(1.0 / Float64(y + -1.0)));
	elseif (y <= 10000000000000.0)
		tmp = Float64(x / Float64(1.0 - y));
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = 1.0 + ((1.0 - x) / y);
	tmp = 0.0;
	if (y <= -11000.0)
		tmp = t_0;
	elseif (y <= -1.05e-63)
		tmp = y * (1.0 / (y + -1.0));
	elseif (y <= 10000000000000.0)
		tmp = x / (1.0 - y);
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(1.0 + N[(N[(1.0 - x), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -11000.0], t$95$0, If[LessEqual[y, -1.05e-63], N[(y * N[(1.0 / N[(y + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 10000000000000.0], N[(x / N[(1.0 - y), $MachinePrecision]), $MachinePrecision], t$95$0]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + \frac{1 - x}{y}\\
\mathbf{if}\;y \leq -11000:\\
\;\;\;\;t_0\\

\mathbf{elif}\;y \leq -1.05 \cdot 10^{-63}:\\
\;\;\;\;y \cdot \frac{1}{y + -1}\\

\mathbf{elif}\;y \leq 10000000000000:\\
\;\;\;\;\frac{x}{1 - y}\\

\mathbf{else}:\\
\;\;\;\;t_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < -11000 or 1e13 < y

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around inf 99.6%

      \[\leadsto \color{blue}{\frac{1}{y} + \left(1 + -1 \cdot \frac{x}{y}\right)} \]
    5. Step-by-step derivation
      1. +-commutative99.6%

        \[\leadsto \frac{1}{y} + \color{blue}{\left(-1 \cdot \frac{x}{y} + 1\right)} \]
      2. associate-+r+99.6%

        \[\leadsto \color{blue}{\left(\frac{1}{y} + -1 \cdot \frac{x}{y}\right) + 1} \]
      3. mul-1-neg99.6%

        \[\leadsto \left(\frac{1}{y} + \color{blue}{\left(-\frac{x}{y}\right)}\right) + 1 \]
      4. unsub-neg99.6%

        \[\leadsto \color{blue}{\left(\frac{1}{y} - \frac{x}{y}\right)} + 1 \]
      5. div-sub99.6%

        \[\leadsto \color{blue}{\frac{1 - x}{y}} + 1 \]
      6. unsub-neg99.6%

        \[\leadsto \frac{\color{blue}{1 + \left(-x\right)}}{y} + 1 \]
      7. mul-1-neg99.6%

        \[\leadsto \frac{1 + \color{blue}{-1 \cdot x}}{y} + 1 \]
      8. +-commutative99.6%

        \[\leadsto \frac{\color{blue}{-1 \cdot x + 1}}{y} + 1 \]
      9. metadata-eval99.6%

        \[\leadsto \frac{-1 \cdot x + \color{blue}{-1 \cdot -1}}{y} + 1 \]
      10. distribute-lft-in99.6%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(x + -1\right)}}{y} + 1 \]
      11. metadata-eval99.6%

        \[\leadsto \frac{-1 \cdot \left(x + \color{blue}{\left(-1\right)}\right)}{y} + 1 \]
      12. sub-neg99.6%

        \[\leadsto \frac{-1 \cdot \color{blue}{\left(x - 1\right)}}{y} + 1 \]
      13. associate-*r/99.6%

        \[\leadsto \color{blue}{-1 \cdot \frac{x - 1}{y}} + 1 \]
      14. +-commutative99.6%

        \[\leadsto \color{blue}{1 + -1 \cdot \frac{x - 1}{y}} \]
      15. associate-*r/99.6%

        \[\leadsto 1 + \color{blue}{\frac{-1 \cdot \left(x - 1\right)}{y}} \]
      16. sub-neg99.6%

        \[\leadsto 1 + \frac{-1 \cdot \color{blue}{\left(x + \left(-1\right)\right)}}{y} \]
      17. metadata-eval99.6%

        \[\leadsto 1 + \frac{-1 \cdot \left(x + \color{blue}{-1}\right)}{y} \]
      18. distribute-lft-in99.6%

        \[\leadsto 1 + \frac{\color{blue}{-1 \cdot x + -1 \cdot -1}}{y} \]
      19. metadata-eval99.6%

        \[\leadsto 1 + \frac{-1 \cdot x + \color{blue}{1}}{y} \]
      20. +-commutative99.6%

        \[\leadsto 1 + \frac{\color{blue}{1 + -1 \cdot x}}{y} \]
      21. mul-1-neg99.6%

        \[\leadsto 1 + \frac{1 + \color{blue}{\left(-x\right)}}{y} \]
      22. unsub-neg99.6%

        \[\leadsto 1 + \frac{\color{blue}{1 - x}}{y} \]
    6. Simplified99.6%

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

    if -11000 < y < -1.05e-63

    1. Initial program 99.8%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg99.8%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative99.8%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub099.8%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-99.8%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg99.8%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-199.8%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub099.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-199.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac99.8%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval99.8%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity99.8%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg99.8%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval99.8%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around 0 62.4%

      \[\leadsto \color{blue}{\frac{y}{y - 1}} \]
    5. Step-by-step derivation
      1. clear-num62.3%

        \[\leadsto \color{blue}{\frac{1}{\frac{y - 1}{y}}} \]
      2. associate-/r/62.5%

        \[\leadsto \color{blue}{\frac{1}{y - 1} \cdot y} \]
      3. sub-neg62.5%

        \[\leadsto \frac{1}{\color{blue}{y + \left(-1\right)}} \cdot y \]
      4. metadata-eval62.5%

        \[\leadsto \frac{1}{y + \color{blue}{-1}} \cdot y \]
    6. Applied egg-rr62.5%

      \[\leadsto \color{blue}{\frac{1}{y + -1} \cdot y} \]

    if -1.05e-63 < y < 1e13

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around inf 83.5%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y - 1}} \]
    5. Step-by-step derivation
      1. sub-neg83.5%

        \[\leadsto -1 \cdot \frac{x}{\color{blue}{y + \left(-1\right)}} \]
      2. metadata-eval83.5%

        \[\leadsto -1 \cdot \frac{x}{y + \color{blue}{-1}} \]
      3. neg-mul-183.5%

        \[\leadsto \color{blue}{-\frac{x}{y + -1}} \]
      4. distribute-neg-frac83.5%

        \[\leadsto \color{blue}{\frac{-x}{y + -1}} \]
      5. +-commutative83.5%

        \[\leadsto \frac{-x}{\color{blue}{-1 + y}} \]
    6. Simplified83.5%

      \[\leadsto \color{blue}{\frac{-x}{-1 + y}} \]
    7. Step-by-step derivation
      1. frac-2neg83.5%

        \[\leadsto \color{blue}{\frac{-\left(-x\right)}{-\left(-1 + y\right)}} \]
      2. +-commutative83.5%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y + -1\right)}} \]
      3. metadata-eval83.5%

        \[\leadsto \frac{-\left(-x\right)}{-\left(y + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg83.5%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y - 1\right)}} \]
      5. div-inv83.5%

        \[\leadsto \color{blue}{\left(-\left(-x\right)\right) \cdot \frac{1}{-\left(y - 1\right)}} \]
      6. remove-double-neg83.5%

        \[\leadsto \color{blue}{x} \cdot \frac{1}{-\left(y - 1\right)} \]
      7. sub-neg83.5%

        \[\leadsto x \cdot \frac{1}{-\color{blue}{\left(y + \left(-1\right)\right)}} \]
      8. metadata-eval83.5%

        \[\leadsto x \cdot \frac{1}{-\left(y + \color{blue}{-1}\right)} \]
      9. distribute-neg-in83.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\left(-y\right) + \left(--1\right)}} \]
      10. neg-mul-183.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{-1 \cdot y} + \left(--1\right)} \]
      11. *-commutative83.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{y \cdot -1} + \left(--1\right)} \]
      12. metadata-eval83.5%

        \[\leadsto x \cdot \frac{1}{y \cdot -1 + \color{blue}{1}} \]
      13. fma-def83.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    8. Applied egg-rr83.5%

      \[\leadsto \color{blue}{x \cdot \frac{1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    9. Step-by-step derivation
      1. associate-*r/83.5%

        \[\leadsto \color{blue}{\frac{x \cdot 1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
      2. *-rgt-identity83.5%

        \[\leadsto \frac{\color{blue}{x}}{\mathsf{fma}\left(y, -1, 1\right)} \]
      3. fma-udef83.5%

        \[\leadsto \frac{x}{\color{blue}{y \cdot -1 + 1}} \]
      4. *-commutative83.5%

        \[\leadsto \frac{x}{\color{blue}{-1 \cdot y} + 1} \]
      5. neg-mul-183.5%

        \[\leadsto \frac{x}{\color{blue}{\left(-y\right)} + 1} \]
      6. +-commutative83.5%

        \[\leadsto \frac{x}{\color{blue}{1 + \left(-y\right)}} \]
      7. unsub-neg83.5%

        \[\leadsto \frac{x}{\color{blue}{1 - y}} \]
    10. Simplified83.5%

      \[\leadsto \color{blue}{\frac{x}{1 - y}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification90.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -11000:\\ \;\;\;\;1 + \frac{1 - x}{y}\\ \mathbf{elif}\;y \leq -1.05 \cdot 10^{-63}:\\ \;\;\;\;y \cdot \frac{1}{y + -1}\\ \mathbf{elif}\;y \leq 10000000000000:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{1 - x}{y}\\ \end{array} \]

Alternative 6: 85.8% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 - \frac{x}{y}\\ \mathbf{if}\;y \leq -15600000000:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq -6 \cdot 10^{-64}:\\ \;\;\;\;\frac{y}{y + -1}\\ \mathbf{elif}\;y \leq 10000000000000:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (- 1.0 (/ x y))))
   (if (<= y -15600000000.0)
     t_0
     (if (<= y -6e-64)
       (/ y (+ y -1.0))
       (if (<= y 10000000000000.0) (/ x (- 1.0 y)) t_0)))))
double code(double x, double y) {
	double t_0 = 1.0 - (x / y);
	double tmp;
	if (y <= -15600000000.0) {
		tmp = t_0;
	} else if (y <= -6e-64) {
		tmp = y / (y + -1.0);
	} else if (y <= 10000000000000.0) {
		tmp = x / (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 - (x / y)
    if (y <= (-15600000000.0d0)) then
        tmp = t_0
    else if (y <= (-6d-64)) then
        tmp = y / (y + (-1.0d0))
    else if (y <= 10000000000000.0d0) then
        tmp = x / (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 - (x / y);
	double tmp;
	if (y <= -15600000000.0) {
		tmp = t_0;
	} else if (y <= -6e-64) {
		tmp = y / (y + -1.0);
	} else if (y <= 10000000000000.0) {
		tmp = x / (1.0 - y);
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 1.0 - (x / y)
	tmp = 0
	if y <= -15600000000.0:
		tmp = t_0
	elif y <= -6e-64:
		tmp = y / (y + -1.0)
	elif y <= 10000000000000.0:
		tmp = x / (1.0 - y)
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(1.0 - Float64(x / y))
	tmp = 0.0
	if (y <= -15600000000.0)
		tmp = t_0;
	elseif (y <= -6e-64)
		tmp = Float64(y / Float64(y + -1.0));
	elseif (y <= 10000000000000.0)
		tmp = Float64(x / Float64(1.0 - y));
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = 1.0 - (x / y);
	tmp = 0.0;
	if (y <= -15600000000.0)
		tmp = t_0;
	elseif (y <= -6e-64)
		tmp = y / (y + -1.0);
	elseif (y <= 10000000000000.0)
		tmp = x / (1.0 - y);
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(1.0 - N[(x / y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -15600000000.0], t$95$0, If[LessEqual[y, -6e-64], N[(y / N[(y + -1.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 10000000000000.0], N[(x / N[(1.0 - y), $MachinePrecision]), $MachinePrecision], t$95$0]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 - \frac{x}{y}\\
\mathbf{if}\;y \leq -15600000000:\\
\;\;\;\;t_0\\

\mathbf{elif}\;y \leq -6 \cdot 10^{-64}:\\
\;\;\;\;\frac{y}{y + -1}\\

\mathbf{elif}\;y \leq 10000000000000:\\
\;\;\;\;\frac{x}{1 - y}\\

\mathbf{else}:\\
\;\;\;\;t_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < -1.56e10 or 1e13 < y

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around inf 100.0%

      \[\leadsto \color{blue}{\frac{1}{y} + \left(1 + -1 \cdot \frac{x}{y}\right)} \]
    5. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{1}{y} + \color{blue}{\left(-1 \cdot \frac{x}{y} + 1\right)} \]
      2. associate-+r+100.0%

        \[\leadsto \color{blue}{\left(\frac{1}{y} + -1 \cdot \frac{x}{y}\right) + 1} \]
      3. mul-1-neg100.0%

        \[\leadsto \left(\frac{1}{y} + \color{blue}{\left(-\frac{x}{y}\right)}\right) + 1 \]
      4. unsub-neg100.0%

        \[\leadsto \color{blue}{\left(\frac{1}{y} - \frac{x}{y}\right)} + 1 \]
      5. div-sub100.0%

        \[\leadsto \color{blue}{\frac{1 - x}{y}} + 1 \]
      6. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{1 + \left(-x\right)}}{y} + 1 \]
      7. mul-1-neg100.0%

        \[\leadsto \frac{1 + \color{blue}{-1 \cdot x}}{y} + 1 \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot x + 1}}{y} + 1 \]
      9. metadata-eval100.0%

        \[\leadsto \frac{-1 \cdot x + \color{blue}{-1 \cdot -1}}{y} + 1 \]
      10. distribute-lft-in100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(x + -1\right)}}{y} + 1 \]
      11. metadata-eval100.0%

        \[\leadsto \frac{-1 \cdot \left(x + \color{blue}{\left(-1\right)}\right)}{y} + 1 \]
      12. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \color{blue}{\left(x - 1\right)}}{y} + 1 \]
      13. associate-*r/100.0%

        \[\leadsto \color{blue}{-1 \cdot \frac{x - 1}{y}} + 1 \]
      14. +-commutative100.0%

        \[\leadsto \color{blue}{1 + -1 \cdot \frac{x - 1}{y}} \]
      15. associate-*r/100.0%

        \[\leadsto 1 + \color{blue}{\frac{-1 \cdot \left(x - 1\right)}{y}} \]
      16. sub-neg100.0%

        \[\leadsto 1 + \frac{-1 \cdot \color{blue}{\left(x + \left(-1\right)\right)}}{y} \]
      17. metadata-eval100.0%

        \[\leadsto 1 + \frac{-1 \cdot \left(x + \color{blue}{-1}\right)}{y} \]
      18. distribute-lft-in100.0%

        \[\leadsto 1 + \frac{\color{blue}{-1 \cdot x + -1 \cdot -1}}{y} \]
      19. metadata-eval100.0%

        \[\leadsto 1 + \frac{-1 \cdot x + \color{blue}{1}}{y} \]
      20. +-commutative100.0%

        \[\leadsto 1 + \frac{\color{blue}{1 + -1 \cdot x}}{y} \]
      21. mul-1-neg100.0%

        \[\leadsto 1 + \frac{1 + \color{blue}{\left(-x\right)}}{y} \]
      22. unsub-neg100.0%

        \[\leadsto 1 + \frac{\color{blue}{1 - x}}{y} \]
    6. Simplified100.0%

      \[\leadsto \color{blue}{1 + \frac{1 - x}{y}} \]
    7. Taylor expanded in x around inf 99.9%

      \[\leadsto 1 + \color{blue}{-1 \cdot \frac{x}{y}} \]
    8. Step-by-step derivation
      1. neg-mul-199.9%

        \[\leadsto 1 + \color{blue}{\left(-\frac{x}{y}\right)} \]
      2. distribute-neg-frac99.9%

        \[\leadsto 1 + \color{blue}{\frac{-x}{y}} \]
    9. Simplified99.9%

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

    if -1.56e10 < y < -6.0000000000000001e-64

    1. Initial program 99.8%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg99.8%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative99.8%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub099.8%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-99.8%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg99.8%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-199.8%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub099.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-199.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac99.8%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval99.8%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity99.8%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg99.8%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval99.8%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around 0 62.8%

      \[\leadsto \color{blue}{\frac{y}{y - 1}} \]

    if -6.0000000000000001e-64 < y < 1e13

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around inf 83.5%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y - 1}} \]
    5. Step-by-step derivation
      1. sub-neg83.5%

        \[\leadsto -1 \cdot \frac{x}{\color{blue}{y + \left(-1\right)}} \]
      2. metadata-eval83.5%

        \[\leadsto -1 \cdot \frac{x}{y + \color{blue}{-1}} \]
      3. neg-mul-183.5%

        \[\leadsto \color{blue}{-\frac{x}{y + -1}} \]
      4. distribute-neg-frac83.5%

        \[\leadsto \color{blue}{\frac{-x}{y + -1}} \]
      5. +-commutative83.5%

        \[\leadsto \frac{-x}{\color{blue}{-1 + y}} \]
    6. Simplified83.5%

      \[\leadsto \color{blue}{\frac{-x}{-1 + y}} \]
    7. Step-by-step derivation
      1. frac-2neg83.5%

        \[\leadsto \color{blue}{\frac{-\left(-x\right)}{-\left(-1 + y\right)}} \]
      2. +-commutative83.5%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y + -1\right)}} \]
      3. metadata-eval83.5%

        \[\leadsto \frac{-\left(-x\right)}{-\left(y + \color{blue}{\left(-1\right)}\right)} \]
      4. sub-neg83.5%

        \[\leadsto \frac{-\left(-x\right)}{-\color{blue}{\left(y - 1\right)}} \]
      5. div-inv83.5%

        \[\leadsto \color{blue}{\left(-\left(-x\right)\right) \cdot \frac{1}{-\left(y - 1\right)}} \]
      6. remove-double-neg83.5%

        \[\leadsto \color{blue}{x} \cdot \frac{1}{-\left(y - 1\right)} \]
      7. sub-neg83.5%

        \[\leadsto x \cdot \frac{1}{-\color{blue}{\left(y + \left(-1\right)\right)}} \]
      8. metadata-eval83.5%

        \[\leadsto x \cdot \frac{1}{-\left(y + \color{blue}{-1}\right)} \]
      9. distribute-neg-in83.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\left(-y\right) + \left(--1\right)}} \]
      10. neg-mul-183.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{-1 \cdot y} + \left(--1\right)} \]
      11. *-commutative83.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{y \cdot -1} + \left(--1\right)} \]
      12. metadata-eval83.5%

        \[\leadsto x \cdot \frac{1}{y \cdot -1 + \color{blue}{1}} \]
      13. fma-def83.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    8. Applied egg-rr83.5%

      \[\leadsto \color{blue}{x \cdot \frac{1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    9. Step-by-step derivation
      1. associate-*r/83.5%

        \[\leadsto \color{blue}{\frac{x \cdot 1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
      2. *-rgt-identity83.5%

        \[\leadsto \frac{\color{blue}{x}}{\mathsf{fma}\left(y, -1, 1\right)} \]
      3. fma-udef83.5%

        \[\leadsto \frac{x}{\color{blue}{y \cdot -1 + 1}} \]
      4. *-commutative83.5%

        \[\leadsto \frac{x}{\color{blue}{-1 \cdot y} + 1} \]
      5. neg-mul-183.5%

        \[\leadsto \frac{x}{\color{blue}{\left(-y\right)} + 1} \]
      6. +-commutative83.5%

        \[\leadsto \frac{x}{\color{blue}{1 + \left(-y\right)}} \]
      7. unsub-neg83.5%

        \[\leadsto \frac{x}{\color{blue}{1 - y}} \]
    10. Simplified83.5%

      \[\leadsto \color{blue}{\frac{x}{1 - y}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification90.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -15600000000:\\ \;\;\;\;1 - \frac{x}{y}\\ \mathbf{elif}\;y \leq -6 \cdot 10^{-64}:\\ \;\;\;\;\frac{y}{y + -1}\\ \mathbf{elif}\;y \leq 10000000000000:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{else}:\\ \;\;\;\;1 - \frac{x}{y}\\ \end{array} \]

Alternative 7: 73.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq -5 \cdot 10^{-64}:\\ \;\;\;\;-y\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -1.0) 1.0 (if (<= y -5e-64) (- y) (if (<= y 1.0) x 1.0))))
double code(double x, double y) {
	double tmp;
	if (y <= -1.0) {
		tmp = 1.0;
	} else if (y <= -5e-64) {
		tmp = -y;
	} else if (y <= 1.0) {
		tmp = x;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= (-1.0d0)) then
        tmp = 1.0d0
    else if (y <= (-5d-64)) then
        tmp = -y
    else if (y <= 1.0d0) then
        tmp = x
    else
        tmp = 1.0d0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -1.0) {
		tmp = 1.0;
	} else if (y <= -5e-64) {
		tmp = -y;
	} else if (y <= 1.0) {
		tmp = x;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -1.0:
		tmp = 1.0
	elif y <= -5e-64:
		tmp = -y
	elif y <= 1.0:
		tmp = x
	else:
		tmp = 1.0
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -1.0)
		tmp = 1.0;
	elseif (y <= -5e-64)
		tmp = Float64(-y);
	elseif (y <= 1.0)
		tmp = x;
	else
		tmp = 1.0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -1.0)
		tmp = 1.0;
	elseif (y <= -5e-64)
		tmp = -y;
	elseif (y <= 1.0)
		tmp = x;
	else
		tmp = 1.0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -1.0], 1.0, If[LessEqual[y, -5e-64], (-y), If[LessEqual[y, 1.0], x, 1.0]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -1:\\
\;\;\;\;1\\

\mathbf{elif}\;y \leq -5 \cdot 10^{-64}:\\
\;\;\;\;-y\\

\mathbf{elif}\;y \leq 1:\\
\;\;\;\;x\\

\mathbf{else}:\\
\;\;\;\;1\\


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

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around inf 74.1%

      \[\leadsto \color{blue}{1} \]

    if -1 < y < -5.00000000000000033e-64

    1. Initial program 99.8%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg99.8%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative99.8%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub099.8%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-99.8%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg99.8%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-199.8%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub099.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg99.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-199.8%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac99.8%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval99.8%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity99.8%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg99.8%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval99.8%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around 0 62.4%

      \[\leadsto \color{blue}{\frac{y}{y - 1}} \]
    5. Taylor expanded in y around 0 54.3%

      \[\leadsto \color{blue}{-1 \cdot y} \]
    6. Step-by-step derivation
      1. neg-mul-154.3%

        \[\leadsto \color{blue}{-y} \]
    7. Simplified54.3%

      \[\leadsto \color{blue}{-y} \]

    if -5.00000000000000033e-64 < y < 1

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around 0 82.1%

      \[\leadsto \color{blue}{x} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification76.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq -5 \cdot 10^{-64}:\\ \;\;\;\;-y\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]

Alternative 8: 74.5% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -0.0023:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -0.0023) 1.0 (if (<= y 1.0) x 1.0)))
double code(double x, double y) {
	double tmp;
	if (y <= -0.0023) {
		tmp = 1.0;
	} else if (y <= 1.0) {
		tmp = x;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= (-0.0023d0)) then
        tmp = 1.0d0
    else if (y <= 1.0d0) then
        tmp = x
    else
        tmp = 1.0d0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -0.0023) {
		tmp = 1.0;
	} else if (y <= 1.0) {
		tmp = x;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -0.0023:
		tmp = 1.0
	elif y <= 1.0:
		tmp = x
	else:
		tmp = 1.0
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -0.0023)
		tmp = 1.0;
	elseif (y <= 1.0)
		tmp = x;
	else
		tmp = 1.0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -0.0023)
		tmp = 1.0;
	elseif (y <= 1.0)
		tmp = x;
	else
		tmp = 1.0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -0.0023], 1.0, If[LessEqual[y, 1.0], x, 1.0]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -0.0023:\\
\;\;\;\;1\\

\mathbf{elif}\;y \leq 1:\\
\;\;\;\;x\\

\mathbf{else}:\\
\;\;\;\;1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -0.0023 or 1 < y

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around inf 73.3%

      \[\leadsto \color{blue}{1} \]

    if -0.0023 < y < 1

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
      2. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

        \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
      6. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
      7. sub-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
      12. neg-mul-1100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around 0 75.6%

      \[\leadsto \color{blue}{x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification74.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -0.0023:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]

Alternative 9: 38.6% accurate, 7.0× 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 100.0%

    \[\frac{x - y}{1 - y} \]
  2. Step-by-step derivation
    1. sub-neg100.0%

      \[\leadsto \frac{\color{blue}{x + \left(-y\right)}}{1 - y} \]
    2. +-commutative100.0%

      \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
    3. neg-sub0100.0%

      \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
    4. associate-+l-100.0%

      \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
    5. sub0-neg100.0%

      \[\leadsto \frac{\color{blue}{-\left(y - x\right)}}{1 - y} \]
    6. neg-mul-1100.0%

      \[\leadsto \frac{\color{blue}{-1 \cdot \left(y - x\right)}}{1 - y} \]
    7. sub-neg100.0%

      \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{1 + \left(-y\right)}} \]
    8. +-commutative100.0%

      \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
    9. neg-sub0100.0%

      \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
    10. associate-+l-100.0%

      \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
    11. sub0-neg100.0%

      \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-\left(y - 1\right)}} \]
    12. neg-mul-1100.0%

      \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
    13. times-frac100.0%

      \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
    14. metadata-eval100.0%

      \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
    15. *-lft-identity100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
    16. sub-neg100.0%

      \[\leadsto \frac{y - x}{\color{blue}{y + \left(-1\right)}} \]
    17. metadata-eval100.0%

      \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
  4. Taylor expanded in y around inf 40.3%

    \[\leadsto \color{blue}{1} \]
  5. Final simplification40.3%

    \[\leadsto 1 \]

Reproduce

?
herbie shell --seed 2023252 
(FPCore (x y)
  :name "Diagrams.Trail:splitAtParam  from diagrams-lib-1.3.0.3, C"
  :precision binary64
  (/ (- x y) (- 1.0 y)))