Linear.Projection:perspective from linear-1.19.1.3, B

Percentage Accurate: 76.1% → 99.8%
Time: 4.8s
Alternatives: 7
Speedup: 0.7×

Specification

?
\[\begin{array}{l} \\ \frac{\left(x \cdot 2\right) \cdot y}{x - y} \end{array} \]
(FPCore (x y) :precision binary64 (/ (* (* x 2.0) y) (- x y)))
double code(double x, double y) {
	return ((x * 2.0) * y) / (x - y);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = ((x * 2.0d0) * y) / (x - y)
end function
public static double code(double x, double y) {
	return ((x * 2.0) * y) / (x - y);
}
def code(x, y):
	return ((x * 2.0) * y) / (x - y)
function code(x, y)
	return Float64(Float64(Float64(x * 2.0) * y) / Float64(x - y))
end
function tmp = code(x, y)
	tmp = ((x * 2.0) * y) / (x - y);
end
code[x_, y_] := N[(N[(N[(x * 2.0), $MachinePrecision] * y), $MachinePrecision] / N[(x - y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(x \cdot 2\right) \cdot y}{x - 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 7 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: 76.1% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\left(x \cdot 2\right) \cdot y}{x - y} \end{array} \]
(FPCore (x y) :precision binary64 (/ (* (* x 2.0) y) (- x y)))
double code(double x, double y) {
	return ((x * 2.0) * y) / (x - y);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = ((x * 2.0d0) * y) / (x - y)
end function
public static double code(double x, double y) {
	return ((x * 2.0) * y) / (x - y);
}
def code(x, y):
	return ((x * 2.0) * y) / (x - y)
function code(x, y)
	return Float64(Float64(Float64(x * 2.0) * y) / Float64(x - y))
end
function tmp = code(x, y)
	tmp = ((x * 2.0) * y) / (x - y);
end
code[x_, y_] := N[(N[(N[(x * 2.0), $MachinePrecision] * y), $MachinePrecision] / N[(x - y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(x \cdot 2\right) \cdot y}{x - y}
\end{array}

Alternative 1: 99.8% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.6 \cdot 10^{+29} \lor \neg \left(y \leq 10^{+41}\right):\\ \;\;\;\;\frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -0.5\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{y}{0.5 + -0.5 \cdot \frac{y}{x}}\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= y -1.6e+29) (not (<= y 1e+41)))
   (/ x (fma 0.5 (/ x y) -0.5))
   (/ y (+ 0.5 (* -0.5 (/ y x))))))
double code(double x, double y) {
	double tmp;
	if ((y <= -1.6e+29) || !(y <= 1e+41)) {
		tmp = x / fma(0.5, (x / y), -0.5);
	} else {
		tmp = y / (0.5 + (-0.5 * (y / x)));
	}
	return tmp;
}
function code(x, y)
	tmp = 0.0
	if ((y <= -1.6e+29) || !(y <= 1e+41))
		tmp = Float64(x / fma(0.5, Float64(x / y), -0.5));
	else
		tmp = Float64(y / Float64(0.5 + Float64(-0.5 * Float64(y / x))));
	end
	return tmp
end
code[x_, y_] := If[Or[LessEqual[y, -1.6e+29], N[Not[LessEqual[y, 1e+41]], $MachinePrecision]], N[(x / N[(0.5 * N[(x / y), $MachinePrecision] + -0.5), $MachinePrecision]), $MachinePrecision], N[(y / N[(0.5 + N[(-0.5 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.6 \cdot 10^{+29} \lor \neg \left(y \leq 10^{+41}\right):\\
\;\;\;\;\frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -0.5\right)}\\

\mathbf{else}:\\
\;\;\;\;\frac{y}{0.5 + -0.5 \cdot \frac{y}{x}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -1.59999999999999993e29 or 1.00000000000000001e41 < y

    1. Initial program 71.9%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. associate-*l*71.9%

        \[\leadsto \frac{\color{blue}{x \cdot \left(2 \cdot y\right)}}{x - y} \]
      2. associate-/l*99.9%

        \[\leadsto \color{blue}{\frac{x}{\frac{x - y}{2 \cdot y}}} \]
      3. div-sub99.9%

        \[\leadsto \frac{x}{\color{blue}{\frac{x}{2 \cdot y} - \frac{y}{2 \cdot y}}} \]
      4. remove-double-neg99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{-\left(-x\right)}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      5. remove-double-neg99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      6. *-lft-identity99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{1 \cdot x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      7. *-inverses99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{\frac{x}{x}} \cdot x}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      8. times-frac99.9%

        \[\leadsto \frac{x}{\color{blue}{\frac{\frac{x}{x}}{2} \cdot \frac{x}{y}} - \frac{y}{2 \cdot y}} \]
      9. *-inverses99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{1}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      10. *-inverses99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{\frac{y}{y}}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      11. associate-/r*99.9%

        \[\leadsto \frac{x}{\color{blue}{\frac{y}{y \cdot 2}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      12. *-commutative99.9%

        \[\leadsto \frac{x}{\frac{y}{\color{blue}{2 \cdot y}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      13. fma-neg99.9%

        \[\leadsto \frac{x}{\color{blue}{\mathsf{fma}\left(\frac{y}{2 \cdot y}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)}} \]
      14. *-commutative99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{y}{\color{blue}{y \cdot 2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      15. associate-/r*99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{\frac{\frac{y}{y}}{2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      16. *-inverses99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{\color{blue}{1}}{2}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      17. metadata-eval99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{0.5}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      18. *-commutative99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{y}{\color{blue}{y \cdot 2}}\right)} \]
      19. associate-/r*99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{\frac{\frac{y}{y}}{2}}\right)} \]
      20. *-inverses99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{\color{blue}{1}}{2}\right)} \]
      21. metadata-eval99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{0.5}\right)} \]
      22. metadata-eval99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, \color{blue}{-0.5}\right)} \]
    3. Simplified99.9%

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

    if -1.59999999999999993e29 < y < 1.00000000000000001e41

    1. Initial program 77.8%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. *-commutative77.8%

        \[\leadsto \frac{\color{blue}{y \cdot \left(x \cdot 2\right)}}{x - y} \]
      2. associate-/l*99.9%

        \[\leadsto \color{blue}{\frac{y}{\frac{x - y}{x \cdot 2}}} \]
      3. div-sub100.0%

        \[\leadsto \frac{y}{\color{blue}{\frac{x}{x \cdot 2} - \frac{y}{x \cdot 2}}} \]
      4. sub-neg100.0%

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

        \[\leadsto \frac{y}{\color{blue}{\left(-\frac{y}{x \cdot 2}\right) + \frac{x}{x \cdot 2}}} \]
      6. distribute-neg-frac100.0%

        \[\leadsto \frac{y}{\color{blue}{\frac{-y}{x \cdot 2}} + \frac{x}{x \cdot 2}} \]
      7. neg-mul-1100.0%

        \[\leadsto \frac{y}{\frac{\color{blue}{-1 \cdot y}}{x \cdot 2} + \frac{x}{x \cdot 2}} \]
      8. *-commutative100.0%

        \[\leadsto \frac{y}{\frac{\color{blue}{y \cdot -1}}{x \cdot 2} + \frac{x}{x \cdot 2}} \]
      9. times-frac100.0%

        \[\leadsto \frac{y}{\color{blue}{\frac{y}{x} \cdot \frac{-1}{2}} + \frac{x}{x \cdot 2}} \]
      10. metadata-eval100.0%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \color{blue}{-0.5} + \frac{x}{x \cdot 2}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \color{blue}{\left(-0.5\right)} + \frac{x}{x \cdot 2}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\color{blue}{\frac{1}{2}}\right) + \frac{x}{x \cdot 2}} \]
      13. *-inverses100.0%

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

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

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

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \color{blue}{\frac{\frac{x}{x}}{2}}} \]
      17. *-inverses100.0%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \frac{\color{blue}{1}}{2}} \]
      18. *-inverses100.0%

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

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

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \frac{y}{\color{blue}{2 \cdot y}}} \]
      21. fma-def100.0%

        \[\leadsto \frac{y}{\color{blue}{\mathsf{fma}\left(\frac{y}{x}, -\frac{y}{2 \cdot y}, \frac{y}{2 \cdot y}\right)}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y}{\mathsf{fma}\left(\frac{y}{x}, -0.5, 0.5\right)}} \]
    4. Taylor expanded in y around 0 100.0%

      \[\leadsto \frac{y}{\color{blue}{-0.5 \cdot \frac{y}{x} + 0.5}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.6 \cdot 10^{+29} \lor \neg \left(y \leq 10^{+41}\right):\\ \;\;\;\;\frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -0.5\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{y}{0.5 + -0.5 \cdot \frac{y}{x}}\\ \end{array} \]

Alternative 2: 99.5% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -8 \cdot 10^{+76} \lor \neg \left(y \leq 2.5 \cdot 10^{+18}\right):\\ \;\;\;\;\frac{x \cdot 2}{\frac{x - y}{y}}\\ \mathbf{else}:\\ \;\;\;\;\frac{y}{0.5 + -0.5 \cdot \frac{y}{x}}\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= y -8e+76) (not (<= y 2.5e+18)))
   (/ (* x 2.0) (/ (- x y) y))
   (/ y (+ 0.5 (* -0.5 (/ y x))))))
double code(double x, double y) {
	double tmp;
	if ((y <= -8e+76) || !(y <= 2.5e+18)) {
		tmp = (x * 2.0) / ((x - y) / y);
	} else {
		tmp = y / (0.5 + (-0.5 * (y / x)));
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if ((y <= (-8d+76)) .or. (.not. (y <= 2.5d+18))) then
        tmp = (x * 2.0d0) / ((x - y) / y)
    else
        tmp = y / (0.5d0 + ((-0.5d0) * (y / x)))
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if ((y <= -8e+76) || !(y <= 2.5e+18)) {
		tmp = (x * 2.0) / ((x - y) / y);
	} else {
		tmp = y / (0.5 + (-0.5 * (y / x)));
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if (y <= -8e+76) or not (y <= 2.5e+18):
		tmp = (x * 2.0) / ((x - y) / y)
	else:
		tmp = y / (0.5 + (-0.5 * (y / x)))
	return tmp
function code(x, y)
	tmp = 0.0
	if ((y <= -8e+76) || !(y <= 2.5e+18))
		tmp = Float64(Float64(x * 2.0) / Float64(Float64(x - y) / y));
	else
		tmp = Float64(y / Float64(0.5 + Float64(-0.5 * Float64(y / x))));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if ((y <= -8e+76) || ~((y <= 2.5e+18)))
		tmp = (x * 2.0) / ((x - y) / y);
	else
		tmp = y / (0.5 + (-0.5 * (y / x)));
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[Or[LessEqual[y, -8e+76], N[Not[LessEqual[y, 2.5e+18]], $MachinePrecision]], N[(N[(x * 2.0), $MachinePrecision] / N[(N[(x - y), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision], N[(y / N[(0.5 + N[(-0.5 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -8 \cdot 10^{+76} \lor \neg \left(y \leq 2.5 \cdot 10^{+18}\right):\\
\;\;\;\;\frac{x \cdot 2}{\frac{x - y}{y}}\\

\mathbf{else}:\\
\;\;\;\;\frac{y}{0.5 + -0.5 \cdot \frac{y}{x}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -8.0000000000000004e76 or 2.5e18 < y

    1. Initial program 69.8%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. associate-/l*99.9%

        \[\leadsto \color{blue}{\frac{x \cdot 2}{\frac{x - y}{y}}} \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\frac{x \cdot 2}{\frac{x - y}{y}}} \]

    if -8.0000000000000004e76 < y < 2.5e18

    1. Initial program 79.0%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. *-commutative79.0%

        \[\leadsto \frac{\color{blue}{y \cdot \left(x \cdot 2\right)}}{x - y} \]
      2. associate-/l*99.9%

        \[\leadsto \color{blue}{\frac{y}{\frac{x - y}{x \cdot 2}}} \]
      3. div-sub99.9%

        \[\leadsto \frac{y}{\color{blue}{\frac{x}{x \cdot 2} - \frac{y}{x \cdot 2}}} \]
      4. sub-neg99.9%

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

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

        \[\leadsto \frac{y}{\color{blue}{\frac{-y}{x \cdot 2}} + \frac{x}{x \cdot 2}} \]
      7. neg-mul-199.9%

        \[\leadsto \frac{y}{\frac{\color{blue}{-1 \cdot y}}{x \cdot 2} + \frac{x}{x \cdot 2}} \]
      8. *-commutative99.9%

        \[\leadsto \frac{y}{\frac{\color{blue}{y \cdot -1}}{x \cdot 2} + \frac{x}{x \cdot 2}} \]
      9. times-frac99.9%

        \[\leadsto \frac{y}{\color{blue}{\frac{y}{x} \cdot \frac{-1}{2}} + \frac{x}{x \cdot 2}} \]
      10. metadata-eval99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \color{blue}{-0.5} + \frac{x}{x \cdot 2}} \]
      11. metadata-eval99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \color{blue}{\left(-0.5\right)} + \frac{x}{x \cdot 2}} \]
      12. metadata-eval99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\color{blue}{\frac{1}{2}}\right) + \frac{x}{x \cdot 2}} \]
      13. *-inverses99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{\color{blue}{\frac{y}{y}}}{2}\right) + \frac{x}{x \cdot 2}} \]
      14. associate-/r*99.9%

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

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{\color{blue}{2 \cdot y}}\right) + \frac{x}{x \cdot 2}} \]
      16. associate-/r*99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \color{blue}{\frac{\frac{x}{x}}{2}}} \]
      17. *-inverses99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \frac{\color{blue}{1}}{2}} \]
      18. *-inverses99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \frac{\color{blue}{\frac{y}{y}}}{2}} \]
      19. associate-/r*99.9%

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

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \frac{y}{\color{blue}{2 \cdot y}}} \]
      21. fma-def99.9%

        \[\leadsto \frac{y}{\color{blue}{\mathsf{fma}\left(\frac{y}{x}, -\frac{y}{2 \cdot y}, \frac{y}{2 \cdot y}\right)}} \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\frac{y}{\mathsf{fma}\left(\frac{y}{x}, -0.5, 0.5\right)}} \]
    4. Taylor expanded in y around 0 99.9%

      \[\leadsto \frac{y}{\color{blue}{-0.5 \cdot \frac{y}{x} + 0.5}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -8 \cdot 10^{+76} \lor \neg \left(y \leq 2.5 \cdot 10^{+18}\right):\\ \;\;\;\;\frac{x \cdot 2}{\frac{x - y}{y}}\\ \mathbf{else}:\\ \;\;\;\;\frac{y}{0.5 + -0.5 \cdot \frac{y}{x}}\\ \end{array} \]

Alternative 3: 74.7% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.8 \cdot 10^{+38}:\\ \;\;\;\;\frac{x}{-0.5}\\ \mathbf{elif}\;y \leq 1.65 \cdot 10^{+58}:\\ \;\;\;\;2 \cdot \left(y + \frac{y}{\frac{x}{y}}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{-0.5}\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -1.8e+38)
   (/ x -0.5)
   (if (<= y 1.65e+58) (* 2.0 (+ y (/ y (/ x y)))) (/ x -0.5))))
double code(double x, double y) {
	double tmp;
	if (y <= -1.8e+38) {
		tmp = x / -0.5;
	} else if (y <= 1.65e+58) {
		tmp = 2.0 * (y + (y / (x / y)));
	} else {
		tmp = x / -0.5;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= (-1.8d+38)) then
        tmp = x / (-0.5d0)
    else if (y <= 1.65d+58) then
        tmp = 2.0d0 * (y + (y / (x / y)))
    else
        tmp = x / (-0.5d0)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -1.8e+38) {
		tmp = x / -0.5;
	} else if (y <= 1.65e+58) {
		tmp = 2.0 * (y + (y / (x / y)));
	} else {
		tmp = x / -0.5;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -1.8e+38:
		tmp = x / -0.5
	elif y <= 1.65e+58:
		tmp = 2.0 * (y + (y / (x / y)))
	else:
		tmp = x / -0.5
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -1.8e+38)
		tmp = Float64(x / -0.5);
	elseif (y <= 1.65e+58)
		tmp = Float64(2.0 * Float64(y + Float64(y / Float64(x / y))));
	else
		tmp = Float64(x / -0.5);
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -1.8e+38)
		tmp = x / -0.5;
	elseif (y <= 1.65e+58)
		tmp = 2.0 * (y + (y / (x / y)));
	else
		tmp = x / -0.5;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -1.8e+38], N[(x / -0.5), $MachinePrecision], If[LessEqual[y, 1.65e+58], N[(2.0 * N[(y + N[(y / N[(x / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x / -0.5), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.8 \cdot 10^{+38}:\\
\;\;\;\;\frac{x}{-0.5}\\

\mathbf{elif}\;y \leq 1.65 \cdot 10^{+58}:\\
\;\;\;\;2 \cdot \left(y + \frac{y}{\frac{x}{y}}\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{x}{-0.5}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -1.79999999999999985e38 or 1.64999999999999991e58 < y

    1. Initial program 69.6%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. associate-*l*69.6%

        \[\leadsto \frac{\color{blue}{x \cdot \left(2 \cdot y\right)}}{x - y} \]
      2. associate-/l*99.9%

        \[\leadsto \color{blue}{\frac{x}{\frac{x - y}{2 \cdot y}}} \]
      3. div-sub99.9%

        \[\leadsto \frac{x}{\color{blue}{\frac{x}{2 \cdot y} - \frac{y}{2 \cdot y}}} \]
      4. remove-double-neg99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{-\left(-x\right)}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      5. remove-double-neg99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      6. *-lft-identity99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{1 \cdot x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      7. *-inverses99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{\frac{x}{x}} \cdot x}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      8. times-frac99.9%

        \[\leadsto \frac{x}{\color{blue}{\frac{\frac{x}{x}}{2} \cdot \frac{x}{y}} - \frac{y}{2 \cdot y}} \]
      9. *-inverses99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{1}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      10. *-inverses99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{\frac{y}{y}}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      11. associate-/r*99.9%

        \[\leadsto \frac{x}{\color{blue}{\frac{y}{y \cdot 2}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      12. *-commutative99.9%

        \[\leadsto \frac{x}{\frac{y}{\color{blue}{2 \cdot y}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      13. fma-neg99.9%

        \[\leadsto \frac{x}{\color{blue}{\mathsf{fma}\left(\frac{y}{2 \cdot y}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)}} \]
      14. *-commutative99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{y}{\color{blue}{y \cdot 2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      15. associate-/r*99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{\frac{\frac{y}{y}}{2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      16. *-inverses99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{\color{blue}{1}}{2}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      17. metadata-eval99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{0.5}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      18. *-commutative99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{y}{\color{blue}{y \cdot 2}}\right)} \]
      19. associate-/r*99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{\frac{\frac{y}{y}}{2}}\right)} \]
      20. *-inverses99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{\color{blue}{1}}{2}\right)} \]
      21. metadata-eval99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{0.5}\right)} \]
      22. metadata-eval99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, \color{blue}{-0.5}\right)} \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -0.5\right)}} \]
    4. Taylor expanded in x around 0 76.8%

      \[\leadsto \frac{x}{\color{blue}{-0.5}} \]

    if -1.79999999999999985e38 < y < 1.64999999999999991e58

    1. Initial program 79.2%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. associate-*l/99.9%

        \[\leadsto \color{blue}{\frac{x \cdot 2}{x - y} \cdot y} \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\frac{x \cdot 2}{x - y} \cdot y} \]
    4. Taylor expanded in x around inf 76.0%

      \[\leadsto \color{blue}{2 \cdot y + 2 \cdot \frac{{y}^{2}}{x}} \]
    5. Step-by-step derivation
      1. distribute-lft-out76.0%

        \[\leadsto \color{blue}{2 \cdot \left(y + \frac{{y}^{2}}{x}\right)} \]
      2. unpow276.0%

        \[\leadsto 2 \cdot \left(y + \frac{\color{blue}{y \cdot y}}{x}\right) \]
      3. associate-/l*76.1%

        \[\leadsto 2 \cdot \left(y + \color{blue}{\frac{y}{\frac{x}{y}}}\right) \]
    6. Simplified76.1%

      \[\leadsto \color{blue}{2 \cdot \left(y + \frac{y}{\frac{x}{y}}\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification76.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.8 \cdot 10^{+38}:\\ \;\;\;\;\frac{x}{-0.5}\\ \mathbf{elif}\;y \leq 1.65 \cdot 10^{+58}:\\ \;\;\;\;2 \cdot \left(y + \frac{y}{\frac{x}{y}}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{-0.5}\\ \end{array} \]

Alternative 4: 93.7% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.7 \cdot 10^{+203}:\\ \;\;\;\;\frac{x}{-0.5}\\ \mathbf{elif}\;y \leq 3.1 \cdot 10^{+228}:\\ \;\;\;\;y \cdot \frac{x \cdot 2}{x - y}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{-0.5}\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -1.7e+203)
   (/ x -0.5)
   (if (<= y 3.1e+228) (* y (/ (* x 2.0) (- x y))) (/ x -0.5))))
double code(double x, double y) {
	double tmp;
	if (y <= -1.7e+203) {
		tmp = x / -0.5;
	} else if (y <= 3.1e+228) {
		tmp = y * ((x * 2.0) / (x - y));
	} else {
		tmp = x / -0.5;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= (-1.7d+203)) then
        tmp = x / (-0.5d0)
    else if (y <= 3.1d+228) then
        tmp = y * ((x * 2.0d0) / (x - y))
    else
        tmp = x / (-0.5d0)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -1.7e+203) {
		tmp = x / -0.5;
	} else if (y <= 3.1e+228) {
		tmp = y * ((x * 2.0) / (x - y));
	} else {
		tmp = x / -0.5;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -1.7e+203:
		tmp = x / -0.5
	elif y <= 3.1e+228:
		tmp = y * ((x * 2.0) / (x - y))
	else:
		tmp = x / -0.5
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -1.7e+203)
		tmp = Float64(x / -0.5);
	elseif (y <= 3.1e+228)
		tmp = Float64(y * Float64(Float64(x * 2.0) / Float64(x - y)));
	else
		tmp = Float64(x / -0.5);
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -1.7e+203)
		tmp = x / -0.5;
	elseif (y <= 3.1e+228)
		tmp = y * ((x * 2.0) / (x - y));
	else
		tmp = x / -0.5;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -1.7e+203], N[(x / -0.5), $MachinePrecision], If[LessEqual[y, 3.1e+228], N[(y * N[(N[(x * 2.0), $MachinePrecision] / N[(x - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x / -0.5), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.7 \cdot 10^{+203}:\\
\;\;\;\;\frac{x}{-0.5}\\

\mathbf{elif}\;y \leq 3.1 \cdot 10^{+228}:\\
\;\;\;\;y \cdot \frac{x \cdot 2}{x - y}\\

\mathbf{else}:\\
\;\;\;\;\frac{x}{-0.5}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -1.7000000000000001e203 or 3.0999999999999999e228 < y

    1. Initial program 57.2%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. associate-*l*57.2%

        \[\leadsto \frac{\color{blue}{x \cdot \left(2 \cdot y\right)}}{x - y} \]
      2. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{x}{\frac{x - y}{2 \cdot y}}} \]
      3. div-sub100.0%

        \[\leadsto \frac{x}{\color{blue}{\frac{x}{2 \cdot y} - \frac{y}{2 \cdot y}}} \]
      4. remove-double-neg100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{-\left(-x\right)}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      5. remove-double-neg100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      6. *-lft-identity100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{1 \cdot x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      7. *-inverses100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{\frac{x}{x}} \cdot x}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      8. times-frac100.0%

        \[\leadsto \frac{x}{\color{blue}{\frac{\frac{x}{x}}{2} \cdot \frac{x}{y}} - \frac{y}{2 \cdot y}} \]
      9. *-inverses100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{1}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      10. *-inverses100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{\frac{y}{y}}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      11. associate-/r*100.0%

        \[\leadsto \frac{x}{\color{blue}{\frac{y}{y \cdot 2}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      12. *-commutative100.0%

        \[\leadsto \frac{x}{\frac{y}{\color{blue}{2 \cdot y}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      13. fma-neg100.0%

        \[\leadsto \frac{x}{\color{blue}{\mathsf{fma}\left(\frac{y}{2 \cdot y}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)}} \]
      14. *-commutative100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{y}{\color{blue}{y \cdot 2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      15. associate-/r*100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{\frac{\frac{y}{y}}{2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      16. *-inverses100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{\color{blue}{1}}{2}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{0.5}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      18. *-commutative100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{y}{\color{blue}{y \cdot 2}}\right)} \]
      19. associate-/r*100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{\frac{\frac{y}{y}}{2}}\right)} \]
      20. *-inverses100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{\color{blue}{1}}{2}\right)} \]
      21. metadata-eval100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{0.5}\right)} \]
      22. metadata-eval100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, \color{blue}{-0.5}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -0.5\right)}} \]
    4. Taylor expanded in x around 0 92.0%

      \[\leadsto \frac{x}{\color{blue}{-0.5}} \]

    if -1.7000000000000001e203 < y < 3.0999999999999999e228

    1. Initial program 78.3%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. associate-*l/96.3%

        \[\leadsto \color{blue}{\frac{x \cdot 2}{x - y} \cdot y} \]
    3. Simplified96.3%

      \[\leadsto \color{blue}{\frac{x \cdot 2}{x - y} \cdot y} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification95.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.7 \cdot 10^{+203}:\\ \;\;\;\;\frac{x}{-0.5}\\ \mathbf{elif}\;y \leq 3.1 \cdot 10^{+228}:\\ \;\;\;\;y \cdot \frac{x \cdot 2}{x - y}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{-0.5}\\ \end{array} \]

Alternative 5: 93.4% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.7 \cdot 10^{+204}:\\ \;\;\;\;\frac{x}{-0.5}\\ \mathbf{elif}\;y \leq 4.2 \cdot 10^{+228}:\\ \;\;\;\;\frac{y}{0.5 + -0.5 \cdot \frac{y}{x}}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{-0.5}\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -1.7e+204)
   (/ x -0.5)
   (if (<= y 4.2e+228) (/ y (+ 0.5 (* -0.5 (/ y x)))) (/ x -0.5))))
double code(double x, double y) {
	double tmp;
	if (y <= -1.7e+204) {
		tmp = x / -0.5;
	} else if (y <= 4.2e+228) {
		tmp = y / (0.5 + (-0.5 * (y / x)));
	} else {
		tmp = x / -0.5;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= (-1.7d+204)) then
        tmp = x / (-0.5d0)
    else if (y <= 4.2d+228) then
        tmp = y / (0.5d0 + ((-0.5d0) * (y / x)))
    else
        tmp = x / (-0.5d0)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -1.7e+204) {
		tmp = x / -0.5;
	} else if (y <= 4.2e+228) {
		tmp = y / (0.5 + (-0.5 * (y / x)));
	} else {
		tmp = x / -0.5;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -1.7e+204:
		tmp = x / -0.5
	elif y <= 4.2e+228:
		tmp = y / (0.5 + (-0.5 * (y / x)))
	else:
		tmp = x / -0.5
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -1.7e+204)
		tmp = Float64(x / -0.5);
	elseif (y <= 4.2e+228)
		tmp = Float64(y / Float64(0.5 + Float64(-0.5 * Float64(y / x))));
	else
		tmp = Float64(x / -0.5);
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -1.7e+204)
		tmp = x / -0.5;
	elseif (y <= 4.2e+228)
		tmp = y / (0.5 + (-0.5 * (y / x)));
	else
		tmp = x / -0.5;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -1.7e+204], N[(x / -0.5), $MachinePrecision], If[LessEqual[y, 4.2e+228], N[(y / N[(0.5 + N[(-0.5 * N[(y / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x / -0.5), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.7 \cdot 10^{+204}:\\
\;\;\;\;\frac{x}{-0.5}\\

\mathbf{elif}\;y \leq 4.2 \cdot 10^{+228}:\\
\;\;\;\;\frac{y}{0.5 + -0.5 \cdot \frac{y}{x}}\\

\mathbf{else}:\\
\;\;\;\;\frac{x}{-0.5}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -1.70000000000000005e204 or 4.19999999999999988e228 < y

    1. Initial program 57.2%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. associate-*l*57.2%

        \[\leadsto \frac{\color{blue}{x \cdot \left(2 \cdot y\right)}}{x - y} \]
      2. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{x}{\frac{x - y}{2 \cdot y}}} \]
      3. div-sub100.0%

        \[\leadsto \frac{x}{\color{blue}{\frac{x}{2 \cdot y} - \frac{y}{2 \cdot y}}} \]
      4. remove-double-neg100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{-\left(-x\right)}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      5. remove-double-neg100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      6. *-lft-identity100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{1 \cdot x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      7. *-inverses100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{\frac{x}{x}} \cdot x}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      8. times-frac100.0%

        \[\leadsto \frac{x}{\color{blue}{\frac{\frac{x}{x}}{2} \cdot \frac{x}{y}} - \frac{y}{2 \cdot y}} \]
      9. *-inverses100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{1}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      10. *-inverses100.0%

        \[\leadsto \frac{x}{\frac{\color{blue}{\frac{y}{y}}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      11. associate-/r*100.0%

        \[\leadsto \frac{x}{\color{blue}{\frac{y}{y \cdot 2}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      12. *-commutative100.0%

        \[\leadsto \frac{x}{\frac{y}{\color{blue}{2 \cdot y}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      13. fma-neg100.0%

        \[\leadsto \frac{x}{\color{blue}{\mathsf{fma}\left(\frac{y}{2 \cdot y}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)}} \]
      14. *-commutative100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{y}{\color{blue}{y \cdot 2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      15. associate-/r*100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{\frac{\frac{y}{y}}{2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      16. *-inverses100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{\color{blue}{1}}{2}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      17. metadata-eval100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{0.5}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      18. *-commutative100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{y}{\color{blue}{y \cdot 2}}\right)} \]
      19. associate-/r*100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{\frac{\frac{y}{y}}{2}}\right)} \]
      20. *-inverses100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{\color{blue}{1}}{2}\right)} \]
      21. metadata-eval100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{0.5}\right)} \]
      22. metadata-eval100.0%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, \color{blue}{-0.5}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -0.5\right)}} \]
    4. Taylor expanded in x around 0 92.0%

      \[\leadsto \frac{x}{\color{blue}{-0.5}} \]

    if -1.70000000000000005e204 < y < 4.19999999999999988e228

    1. Initial program 78.3%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. *-commutative78.3%

        \[\leadsto \frac{\color{blue}{y \cdot \left(x \cdot 2\right)}}{x - y} \]
      2. associate-/l*96.4%

        \[\leadsto \color{blue}{\frac{y}{\frac{x - y}{x \cdot 2}}} \]
      3. div-sub96.4%

        \[\leadsto \frac{y}{\color{blue}{\frac{x}{x \cdot 2} - \frac{y}{x \cdot 2}}} \]
      4. sub-neg96.4%

        \[\leadsto \frac{y}{\color{blue}{\frac{x}{x \cdot 2} + \left(-\frac{y}{x \cdot 2}\right)}} \]
      5. +-commutative96.4%

        \[\leadsto \frac{y}{\color{blue}{\left(-\frac{y}{x \cdot 2}\right) + \frac{x}{x \cdot 2}}} \]
      6. distribute-neg-frac96.4%

        \[\leadsto \frac{y}{\color{blue}{\frac{-y}{x \cdot 2}} + \frac{x}{x \cdot 2}} \]
      7. neg-mul-196.4%

        \[\leadsto \frac{y}{\frac{\color{blue}{-1 \cdot y}}{x \cdot 2} + \frac{x}{x \cdot 2}} \]
      8. *-commutative96.4%

        \[\leadsto \frac{y}{\frac{\color{blue}{y \cdot -1}}{x \cdot 2} + \frac{x}{x \cdot 2}} \]
      9. times-frac96.4%

        \[\leadsto \frac{y}{\color{blue}{\frac{y}{x} \cdot \frac{-1}{2}} + \frac{x}{x \cdot 2}} \]
      10. metadata-eval96.4%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \color{blue}{-0.5} + \frac{x}{x \cdot 2}} \]
      11. metadata-eval96.4%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \color{blue}{\left(-0.5\right)} + \frac{x}{x \cdot 2}} \]
      12. metadata-eval96.4%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\color{blue}{\frac{1}{2}}\right) + \frac{x}{x \cdot 2}} \]
      13. *-inverses96.4%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{\color{blue}{\frac{y}{y}}}{2}\right) + \frac{x}{x \cdot 2}} \]
      14. associate-/r*96.4%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\color{blue}{\frac{y}{y \cdot 2}}\right) + \frac{x}{x \cdot 2}} \]
      15. *-commutative96.4%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{\color{blue}{2 \cdot y}}\right) + \frac{x}{x \cdot 2}} \]
      16. associate-/r*96.4%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \color{blue}{\frac{\frac{x}{x}}{2}}} \]
      17. *-inverses96.4%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \frac{\color{blue}{1}}{2}} \]
      18. *-inverses96.4%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \frac{\color{blue}{\frac{y}{y}}}{2}} \]
      19. associate-/r*96.4%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \color{blue}{\frac{y}{y \cdot 2}}} \]
      20. *-commutative96.4%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \frac{y}{\color{blue}{2 \cdot y}}} \]
      21. fma-def96.4%

        \[\leadsto \frac{y}{\color{blue}{\mathsf{fma}\left(\frac{y}{x}, -\frac{y}{2 \cdot y}, \frac{y}{2 \cdot y}\right)}} \]
    3. Simplified96.4%

      \[\leadsto \color{blue}{\frac{y}{\mathsf{fma}\left(\frac{y}{x}, -0.5, 0.5\right)}} \]
    4. Taylor expanded in y around 0 96.4%

      \[\leadsto \frac{y}{\color{blue}{-0.5 \cdot \frac{y}{x} + 0.5}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification95.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.7 \cdot 10^{+204}:\\ \;\;\;\;\frac{x}{-0.5}\\ \mathbf{elif}\;y \leq 4.2 \cdot 10^{+228}:\\ \;\;\;\;\frac{y}{0.5 + -0.5 \cdot \frac{y}{x}}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{-0.5}\\ \end{array} \]

Alternative 6: 74.9% accurate, 1.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -2.95 \cdot 10^{+32}:\\ \;\;\;\;\frac{x}{-0.5}\\ \mathbf{elif}\;y \leq 5.2 \cdot 10^{+57}:\\ \;\;\;\;\frac{y}{0.5}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{-0.5}\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -2.95e+32) (/ x -0.5) (if (<= y 5.2e+57) (/ y 0.5) (/ x -0.5))))
double code(double x, double y) {
	double tmp;
	if (y <= -2.95e+32) {
		tmp = x / -0.5;
	} else if (y <= 5.2e+57) {
		tmp = y / 0.5;
	} else {
		tmp = x / -0.5;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (y <= (-2.95d+32)) then
        tmp = x / (-0.5d0)
    else if (y <= 5.2d+57) then
        tmp = y / 0.5d0
    else
        tmp = x / (-0.5d0)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -2.95e+32) {
		tmp = x / -0.5;
	} else if (y <= 5.2e+57) {
		tmp = y / 0.5;
	} else {
		tmp = x / -0.5;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -2.95e+32:
		tmp = x / -0.5
	elif y <= 5.2e+57:
		tmp = y / 0.5
	else:
		tmp = x / -0.5
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -2.95e+32)
		tmp = Float64(x / -0.5);
	elseif (y <= 5.2e+57)
		tmp = Float64(y / 0.5);
	else
		tmp = Float64(x / -0.5);
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -2.95e+32)
		tmp = x / -0.5;
	elseif (y <= 5.2e+57)
		tmp = y / 0.5;
	else
		tmp = x / -0.5;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -2.95e+32], N[(x / -0.5), $MachinePrecision], If[LessEqual[y, 5.2e+57], N[(y / 0.5), $MachinePrecision], N[(x / -0.5), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -2.95 \cdot 10^{+32}:\\
\;\;\;\;\frac{x}{-0.5}\\

\mathbf{elif}\;y \leq 5.2 \cdot 10^{+57}:\\
\;\;\;\;\frac{y}{0.5}\\

\mathbf{else}:\\
\;\;\;\;\frac{x}{-0.5}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -2.94999999999999983e32 or 5.2e57 < y

    1. Initial program 70.6%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. associate-*l*70.6%

        \[\leadsto \frac{\color{blue}{x \cdot \left(2 \cdot y\right)}}{x - y} \]
      2. associate-/l*99.9%

        \[\leadsto \color{blue}{\frac{x}{\frac{x - y}{2 \cdot y}}} \]
      3. div-sub99.9%

        \[\leadsto \frac{x}{\color{blue}{\frac{x}{2 \cdot y} - \frac{y}{2 \cdot y}}} \]
      4. remove-double-neg99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{-\left(-x\right)}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      5. remove-double-neg99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      6. *-lft-identity99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{1 \cdot x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      7. *-inverses99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{\frac{x}{x}} \cdot x}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
      8. times-frac99.9%

        \[\leadsto \frac{x}{\color{blue}{\frac{\frac{x}{x}}{2} \cdot \frac{x}{y}} - \frac{y}{2 \cdot y}} \]
      9. *-inverses99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{1}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      10. *-inverses99.9%

        \[\leadsto \frac{x}{\frac{\color{blue}{\frac{y}{y}}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      11. associate-/r*99.9%

        \[\leadsto \frac{x}{\color{blue}{\frac{y}{y \cdot 2}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      12. *-commutative99.9%

        \[\leadsto \frac{x}{\frac{y}{\color{blue}{2 \cdot y}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
      13. fma-neg99.9%

        \[\leadsto \frac{x}{\color{blue}{\mathsf{fma}\left(\frac{y}{2 \cdot y}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)}} \]
      14. *-commutative99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{y}{\color{blue}{y \cdot 2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      15. associate-/r*99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{\frac{\frac{y}{y}}{2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      16. *-inverses99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{\color{blue}{1}}{2}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      17. metadata-eval99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{0.5}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
      18. *-commutative99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{y}{\color{blue}{y \cdot 2}}\right)} \]
      19. associate-/r*99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{\frac{\frac{y}{y}}{2}}\right)} \]
      20. *-inverses99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{\color{blue}{1}}{2}\right)} \]
      21. metadata-eval99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{0.5}\right)} \]
      22. metadata-eval99.9%

        \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, \color{blue}{-0.5}\right)} \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -0.5\right)}} \]
    4. Taylor expanded in x around 0 75.9%

      \[\leadsto \frac{x}{\color{blue}{-0.5}} \]

    if -2.94999999999999983e32 < y < 5.2e57

    1. Initial program 78.6%

      \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
    2. Step-by-step derivation
      1. *-commutative78.6%

        \[\leadsto \frac{\color{blue}{y \cdot \left(x \cdot 2\right)}}{x - y} \]
      2. associate-/l*99.9%

        \[\leadsto \color{blue}{\frac{y}{\frac{x - y}{x \cdot 2}}} \]
      3. div-sub99.9%

        \[\leadsto \frac{y}{\color{blue}{\frac{x}{x \cdot 2} - \frac{y}{x \cdot 2}}} \]
      4. sub-neg99.9%

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

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

        \[\leadsto \frac{y}{\color{blue}{\frac{-y}{x \cdot 2}} + \frac{x}{x \cdot 2}} \]
      7. neg-mul-199.9%

        \[\leadsto \frac{y}{\frac{\color{blue}{-1 \cdot y}}{x \cdot 2} + \frac{x}{x \cdot 2}} \]
      8. *-commutative99.9%

        \[\leadsto \frac{y}{\frac{\color{blue}{y \cdot -1}}{x \cdot 2} + \frac{x}{x \cdot 2}} \]
      9. times-frac99.9%

        \[\leadsto \frac{y}{\color{blue}{\frac{y}{x} \cdot \frac{-1}{2}} + \frac{x}{x \cdot 2}} \]
      10. metadata-eval99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \color{blue}{-0.5} + \frac{x}{x \cdot 2}} \]
      11. metadata-eval99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \color{blue}{\left(-0.5\right)} + \frac{x}{x \cdot 2}} \]
      12. metadata-eval99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\color{blue}{\frac{1}{2}}\right) + \frac{x}{x \cdot 2}} \]
      13. *-inverses99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{\color{blue}{\frac{y}{y}}}{2}\right) + \frac{x}{x \cdot 2}} \]
      14. associate-/r*99.9%

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

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{\color{blue}{2 \cdot y}}\right) + \frac{x}{x \cdot 2}} \]
      16. associate-/r*99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \color{blue}{\frac{\frac{x}{x}}{2}}} \]
      17. *-inverses99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \frac{\color{blue}{1}}{2}} \]
      18. *-inverses99.9%

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \frac{\color{blue}{\frac{y}{y}}}{2}} \]
      19. associate-/r*99.9%

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

        \[\leadsto \frac{y}{\frac{y}{x} \cdot \left(-\frac{y}{2 \cdot y}\right) + \frac{y}{\color{blue}{2 \cdot y}}} \]
      21. fma-def99.9%

        \[\leadsto \frac{y}{\color{blue}{\mathsf{fma}\left(\frac{y}{x}, -\frac{y}{2 \cdot y}, \frac{y}{2 \cdot y}\right)}} \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\frac{y}{\mathsf{fma}\left(\frac{y}{x}, -0.5, 0.5\right)}} \]
    4. Taylor expanded in y around 0 76.2%

      \[\leadsto \frac{y}{\color{blue}{0.5}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification76.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -2.95 \cdot 10^{+32}:\\ \;\;\;\;\frac{x}{-0.5}\\ \mathbf{elif}\;y \leq 5.2 \cdot 10^{+57}:\\ \;\;\;\;\frac{y}{0.5}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{-0.5}\\ \end{array} \]

Alternative 7: 50.9% accurate, 3.0× speedup?

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

\\
\frac{x}{-0.5}
\end{array}
Derivation
  1. Initial program 74.8%

    \[\frac{\left(x \cdot 2\right) \cdot y}{x - y} \]
  2. Step-by-step derivation
    1. associate-*l*74.8%

      \[\leadsto \frac{\color{blue}{x \cdot \left(2 \cdot y\right)}}{x - y} \]
    2. associate-/l*90.8%

      \[\leadsto \color{blue}{\frac{x}{\frac{x - y}{2 \cdot y}}} \]
    3. div-sub90.8%

      \[\leadsto \frac{x}{\color{blue}{\frac{x}{2 \cdot y} - \frac{y}{2 \cdot y}}} \]
    4. remove-double-neg90.8%

      \[\leadsto \frac{x}{\frac{\color{blue}{-\left(-x\right)}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
    5. remove-double-neg90.8%

      \[\leadsto \frac{x}{\frac{\color{blue}{x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
    6. *-lft-identity90.8%

      \[\leadsto \frac{x}{\frac{\color{blue}{1 \cdot x}}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
    7. *-inverses90.8%

      \[\leadsto \frac{x}{\frac{\color{blue}{\frac{x}{x}} \cdot x}{2 \cdot y} - \frac{y}{2 \cdot y}} \]
    8. times-frac90.8%

      \[\leadsto \frac{x}{\color{blue}{\frac{\frac{x}{x}}{2} \cdot \frac{x}{y}} - \frac{y}{2 \cdot y}} \]
    9. *-inverses90.8%

      \[\leadsto \frac{x}{\frac{\color{blue}{1}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
    10. *-inverses90.8%

      \[\leadsto \frac{x}{\frac{\color{blue}{\frac{y}{y}}}{2} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
    11. associate-/r*90.8%

      \[\leadsto \frac{x}{\color{blue}{\frac{y}{y \cdot 2}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
    12. *-commutative90.8%

      \[\leadsto \frac{x}{\frac{y}{\color{blue}{2 \cdot y}} \cdot \frac{x}{y} - \frac{y}{2 \cdot y}} \]
    13. fma-neg90.8%

      \[\leadsto \frac{x}{\color{blue}{\mathsf{fma}\left(\frac{y}{2 \cdot y}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)}} \]
    14. *-commutative90.8%

      \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{y}{\color{blue}{y \cdot 2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
    15. associate-/r*90.8%

      \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{\frac{\frac{y}{y}}{2}}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
    16. *-inverses90.8%

      \[\leadsto \frac{x}{\mathsf{fma}\left(\frac{\color{blue}{1}}{2}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
    17. metadata-eval90.8%

      \[\leadsto \frac{x}{\mathsf{fma}\left(\color{blue}{0.5}, \frac{x}{y}, -\frac{y}{2 \cdot y}\right)} \]
    18. *-commutative90.8%

      \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{y}{\color{blue}{y \cdot 2}}\right)} \]
    19. associate-/r*90.8%

      \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{\frac{\frac{y}{y}}{2}}\right)} \]
    20. *-inverses90.8%

      \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\frac{\color{blue}{1}}{2}\right)} \]
    21. metadata-eval90.8%

      \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -\color{blue}{0.5}\right)} \]
    22. metadata-eval90.8%

      \[\leadsto \frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, \color{blue}{-0.5}\right)} \]
  3. Simplified90.8%

    \[\leadsto \color{blue}{\frac{x}{\mathsf{fma}\left(0.5, \frac{x}{y}, -0.5\right)}} \]
  4. Taylor expanded in x around 0 48.7%

    \[\leadsto \frac{x}{\color{blue}{-0.5}} \]
  5. Final simplification48.7%

    \[\leadsto \frac{x}{-0.5} \]

Developer target: 99.6% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{2 \cdot x}{x - y} \cdot y\\ \mathbf{if}\;x < -1.7210442634149447 \cdot 10^{+81}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;x < 83645045635564430:\\ \;\;\;\;\frac{x \cdot 2}{\frac{x - y}{y}}\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (* (/ (* 2.0 x) (- x y)) y)))
   (if (< x -1.7210442634149447e+81)
     t_0
     (if (< x 83645045635564430.0) (/ (* x 2.0) (/ (- x y) y)) t_0))))
double code(double x, double y) {
	double t_0 = ((2.0 * x) / (x - y)) * y;
	double tmp;
	if (x < -1.7210442634149447e+81) {
		tmp = t_0;
	} else if (x < 83645045635564430.0) {
		tmp = (x * 2.0) / ((x - y) / 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 = ((2.0d0 * x) / (x - y)) * y
    if (x < (-1.7210442634149447d+81)) then
        tmp = t_0
    else if (x < 83645045635564430.0d0) then
        tmp = (x * 2.0d0) / ((x - y) / y)
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double t_0 = ((2.0 * x) / (x - y)) * y;
	double tmp;
	if (x < -1.7210442634149447e+81) {
		tmp = t_0;
	} else if (x < 83645045635564430.0) {
		tmp = (x * 2.0) / ((x - y) / y);
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = ((2.0 * x) / (x - y)) * y
	tmp = 0
	if x < -1.7210442634149447e+81:
		tmp = t_0
	elif x < 83645045635564430.0:
		tmp = (x * 2.0) / ((x - y) / y)
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(Float64(Float64(2.0 * x) / Float64(x - y)) * y)
	tmp = 0.0
	if (x < -1.7210442634149447e+81)
		tmp = t_0;
	elseif (x < 83645045635564430.0)
		tmp = Float64(Float64(x * 2.0) / Float64(Float64(x - y) / y));
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = ((2.0 * x) / (x - y)) * y;
	tmp = 0.0;
	if (x < -1.7210442634149447e+81)
		tmp = t_0;
	elseif (x < 83645045635564430.0)
		tmp = (x * 2.0) / ((x - y) / y);
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(N[(N[(2.0 * x), $MachinePrecision] / N[(x - y), $MachinePrecision]), $MachinePrecision] * y), $MachinePrecision]}, If[Less[x, -1.7210442634149447e+81], t$95$0, If[Less[x, 83645045635564430.0], N[(N[(x * 2.0), $MachinePrecision] / N[(N[(x - y), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision], t$95$0]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{2 \cdot x}{x - y} \cdot y\\
\mathbf{if}\;x < -1.7210442634149447 \cdot 10^{+81}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;x < 83645045635564430:\\
\;\;\;\;\frac{x \cdot 2}{\frac{x - y}{y}}\\

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


\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2023224 
(FPCore (x y)
  :name "Linear.Projection:perspective from linear-1.19.1.3, B"
  :precision binary64

  :herbie-target
  (if (< x -1.7210442634149447e+81) (* (/ (* 2.0 x) (- x y)) y) (if (< x 83645045635564430.0) (/ (* x 2.0) (/ (- x y) y)) (* (/ (* 2.0 x) (- x y)) y)))

  (/ (* (* x 2.0) y) (- x y)))