_divideComplex, real part

Percentage Accurate: 61.6% → 83.2%
Time: 8.0s
Alternatives: 10
Speedup: 1.6×

Specification

?
\[\begin{array}{l} \\ \frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (/ (+ (* x.re y.re) (* x.im y.im)) (+ (* y.re y.re) (* y.im y.im))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	return ((x_46_re * y_46_re) + (x_46_im * y_46_im)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
}
real(8) function code(x_46re, x_46im, y_46re, y_46im)
    real(8), intent (in) :: x_46re
    real(8), intent (in) :: x_46im
    real(8), intent (in) :: y_46re
    real(8), intent (in) :: y_46im
    code = ((x_46re * y_46re) + (x_46im * y_46im)) / ((y_46re * y_46re) + (y_46im * y_46im))
end function
public static double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	return ((x_46_re * y_46_re) + (x_46_im * y_46_im)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	return ((x_46_re * y_46_re) + (x_46_im * y_46_im)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im))
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	return Float64(Float64(Float64(x_46_re * y_46_re) + Float64(x_46_im * y_46_im)) / Float64(Float64(y_46_re * y_46_re) + Float64(y_46_im * y_46_im)))
end
function tmp = code(x_46_re, x_46_im, y_46_re, y_46_im)
	tmp = ((x_46_re * y_46_re) + (x_46_im * y_46_im)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := N[(N[(N[(x$46$re * y$46$re), $MachinePrecision] + N[(x$46$im * y$46$im), $MachinePrecision]), $MachinePrecision] / N[(N[(y$46$re * y$46$re), $MachinePrecision] + N[(y$46$im * y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 10 alternatives:

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

Initial Program: 61.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (/ (+ (* x.re y.re) (* x.im y.im)) (+ (* y.re y.re) (* y.im y.im))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	return ((x_46_re * y_46_re) + (x_46_im * y_46_im)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
}
real(8) function code(x_46re, x_46im, y_46re, y_46im)
    real(8), intent (in) :: x_46re
    real(8), intent (in) :: x_46im
    real(8), intent (in) :: y_46re
    real(8), intent (in) :: y_46im
    code = ((x_46re * y_46re) + (x_46im * y_46im)) / ((y_46re * y_46re) + (y_46im * y_46im))
end function
public static double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	return ((x_46_re * y_46_re) + (x_46_im * y_46_im)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	return ((x_46_re * y_46_re) + (x_46_im * y_46_im)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im))
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	return Float64(Float64(Float64(x_46_re * y_46_re) + Float64(x_46_im * y_46_im)) / Float64(Float64(y_46_re * y_46_re) + Float64(y_46_im * y_46_im)))
end
function tmp = code(x_46_re, x_46_im, y_46_re, y_46_im)
	tmp = ((x_46_re * y_46_re) + (x_46_im * y_46_im)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := N[(N[(N[(x$46$re * y$46$re), $MachinePrecision] + N[(x$46$im * y$46$im), $MachinePrecision]), $MachinePrecision] / N[(N[(y$46$re * y$46$re), $MachinePrecision] + N[(y$46$im * y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}
\end{array}

Alternative 1: 83.2% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{y.im \cdot x.im + x.re \cdot y.re}{y.im \cdot y.im + y.re \cdot y.re}\\ t_1 := \frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}\\ \mathbf{if}\;y.re \leq -3.2 \cdot 10^{+94}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;y.re \leq -6.8 \cdot 10^{-38}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y.re \leq 1.05 \cdot 10^{-155}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\frac{y.re}{y.im}, x.re, x.im\right)}{y.im}\\ \mathbf{elif}\;y.re \leq 3.1 \cdot 10^{+121}:\\ \;\;\;\;t\_0\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0
         (/ (+ (* y.im x.im) (* x.re y.re)) (+ (* y.im y.im) (* y.re y.re))))
        (t_1 (/ (fma (/ x.im y.re) y.im x.re) y.re)))
   (if (<= y.re -3.2e+94)
     t_1
     (if (<= y.re -6.8e-38)
       t_0
       (if (<= y.re 1.05e-155)
         (/ (fma (/ y.re y.im) x.re x.im) y.im)
         (if (<= y.re 3.1e+121) t_0 t_1))))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = ((y_46_im * x_46_im) + (x_46_re * y_46_re)) / ((y_46_im * y_46_im) + (y_46_re * y_46_re));
	double t_1 = fma((x_46_im / y_46_re), y_46_im, x_46_re) / y_46_re;
	double tmp;
	if (y_46_re <= -3.2e+94) {
		tmp = t_1;
	} else if (y_46_re <= -6.8e-38) {
		tmp = t_0;
	} else if (y_46_re <= 1.05e-155) {
		tmp = fma((y_46_re / y_46_im), x_46_re, x_46_im) / y_46_im;
	} else if (y_46_re <= 3.1e+121) {
		tmp = t_0;
	} else {
		tmp = t_1;
	}
	return tmp;
}
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = Float64(Float64(Float64(y_46_im * x_46_im) + Float64(x_46_re * y_46_re)) / Float64(Float64(y_46_im * y_46_im) + Float64(y_46_re * y_46_re)))
	t_1 = Float64(fma(Float64(x_46_im / y_46_re), y_46_im, x_46_re) / y_46_re)
	tmp = 0.0
	if (y_46_re <= -3.2e+94)
		tmp = t_1;
	elseif (y_46_re <= -6.8e-38)
		tmp = t_0;
	elseif (y_46_re <= 1.05e-155)
		tmp = Float64(fma(Float64(y_46_re / y_46_im), x_46_re, x_46_im) / y_46_im);
	elseif (y_46_re <= 3.1e+121)
		tmp = t_0;
	else
		tmp = t_1;
	end
	return tmp
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[(N[(N[(y$46$im * x$46$im), $MachinePrecision] + N[(x$46$re * y$46$re), $MachinePrecision]), $MachinePrecision] / N[(N[(y$46$im * y$46$im), $MachinePrecision] + N[(y$46$re * y$46$re), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(N[(x$46$im / y$46$re), $MachinePrecision] * y$46$im + x$46$re), $MachinePrecision] / y$46$re), $MachinePrecision]}, If[LessEqual[y$46$re, -3.2e+94], t$95$1, If[LessEqual[y$46$re, -6.8e-38], t$95$0, If[LessEqual[y$46$re, 1.05e-155], N[(N[(N[(y$46$re / y$46$im), $MachinePrecision] * x$46$re + x$46$im), $MachinePrecision] / y$46$im), $MachinePrecision], If[LessEqual[y$46$re, 3.1e+121], t$95$0, t$95$1]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{y.im \cdot x.im + x.re \cdot y.re}{y.im \cdot y.im + y.re \cdot y.re}\\
t_1 := \frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}\\
\mathbf{if}\;y.re \leq -3.2 \cdot 10^{+94}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;y.re \leq -6.8 \cdot 10^{-38}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;y.re \leq 1.05 \cdot 10^{-155}:\\
\;\;\;\;\frac{\mathsf{fma}\left(\frac{y.re}{y.im}, x.re, x.im\right)}{y.im}\\

\mathbf{elif}\;y.re \leq 3.1 \cdot 10^{+121}:\\
\;\;\;\;t\_0\\

\mathbf{else}:\\
\;\;\;\;t\_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y.re < -3.20000000000000014e94 or 3.10000000000000008e121 < y.re

    1. Initial program 40.4%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around inf

      \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im \cdot y.im}{y.re} + x.re}}{y.re} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{y.im \cdot x.im}}{y.re} + x.re}{y.re} \]
      4. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{y.im \cdot \frac{x.im}{y.re}} + x.re}{y.re} \]
      5. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im}{y.re} \cdot y.im} + x.re}{y.re} \]
      6. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}}{y.re} \]
      7. lower-/.f6488.7

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{x.im}{y.re}}, y.im, x.re\right)}{y.re} \]
    5. Applied rewrites88.7%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}} \]

    if -3.20000000000000014e94 < y.re < -6.8000000000000004e-38 or 1.0500000000000001e-155 < y.re < 3.10000000000000008e121

    1. Initial program 81.7%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing

    if -6.8000000000000004e-38 < y.re < 1.0500000000000001e-155

    1. Initial program 67.7%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around inf

      \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im \cdot y.im}{y.re} + x.re}}{y.re} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{y.im \cdot x.im}}{y.re} + x.re}{y.re} \]
      4. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{y.im \cdot \frac{x.im}{y.re}} + x.re}{y.re} \]
      5. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im}{y.re} \cdot y.im} + x.re}{y.re} \]
      6. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}}{y.re} \]
      7. lower-/.f6422.9

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{x.im}{y.re}}, y.im, x.re\right)}{y.re} \]
    5. Applied rewrites22.9%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}} \]
    6. Taylor expanded in y.im around inf

      \[\leadsto \color{blue}{\frac{x.im + \frac{x.re \cdot y.re}{y.im}}{y.im}} \]
    7. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.im + \frac{x.re \cdot y.re}{y.im}}{y.im}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.re \cdot y.re}{y.im} + x.im}}{y.im} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{y.re \cdot x.re}}{y.im} + x.im}{y.im} \]
      4. associate-*l/N/A

        \[\leadsto \frac{\color{blue}{\frac{y.re}{y.im} \cdot x.re} + x.im}{y.im} \]
      5. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{y.re}{y.im}, x.re, x.im\right)}}{y.im} \]
      6. lower-/.f6495.1

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{y.re}{y.im}}, x.re, x.im\right)}{y.im} \]
    8. Applied rewrites95.1%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{y.re}{y.im}, x.re, x.im\right)}{y.im}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification88.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y.re \leq -3.2 \cdot 10^{+94}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}\\ \mathbf{elif}\;y.re \leq -6.8 \cdot 10^{-38}:\\ \;\;\;\;\frac{y.im \cdot x.im + x.re \cdot y.re}{y.im \cdot y.im + y.re \cdot y.re}\\ \mathbf{elif}\;y.re \leq 1.05 \cdot 10^{-155}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\frac{y.re}{y.im}, x.re, x.im\right)}{y.im}\\ \mathbf{elif}\;y.re \leq 3.1 \cdot 10^{+121}:\\ \;\;\;\;\frac{y.im \cdot x.im + x.re \cdot y.re}{y.im \cdot y.im + y.re \cdot y.re}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 70.4% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}\\ \mathbf{if}\;y.re \leq -48:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y.re \leq -1.26 \cdot 10^{-170}:\\ \;\;\;\;\frac{\mathsf{fma}\left(y.re, x.re, y.im \cdot x.im\right)}{y.im \cdot y.im}\\ \mathbf{elif}\;y.re \leq 6 \cdot 10^{-71}:\\ \;\;\;\;\frac{x.im}{y.im}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0 (/ (fma (/ x.im y.re) y.im x.re) y.re)))
   (if (<= y.re -48.0)
     t_0
     (if (<= y.re -1.26e-170)
       (/ (fma y.re x.re (* y.im x.im)) (* y.im y.im))
       (if (<= y.re 6e-71) (/ x.im y.im) t_0)))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = fma((x_46_im / y_46_re), y_46_im, x_46_re) / y_46_re;
	double tmp;
	if (y_46_re <= -48.0) {
		tmp = t_0;
	} else if (y_46_re <= -1.26e-170) {
		tmp = fma(y_46_re, x_46_re, (y_46_im * x_46_im)) / (y_46_im * y_46_im);
	} else if (y_46_re <= 6e-71) {
		tmp = x_46_im / y_46_im;
	} else {
		tmp = t_0;
	}
	return tmp;
}
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = Float64(fma(Float64(x_46_im / y_46_re), y_46_im, x_46_re) / y_46_re)
	tmp = 0.0
	if (y_46_re <= -48.0)
		tmp = t_0;
	elseif (y_46_re <= -1.26e-170)
		tmp = Float64(fma(y_46_re, x_46_re, Float64(y_46_im * x_46_im)) / Float64(y_46_im * y_46_im));
	elseif (y_46_re <= 6e-71)
		tmp = Float64(x_46_im / y_46_im);
	else
		tmp = t_0;
	end
	return tmp
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[(N[(N[(x$46$im / y$46$re), $MachinePrecision] * y$46$im + x$46$re), $MachinePrecision] / y$46$re), $MachinePrecision]}, If[LessEqual[y$46$re, -48.0], t$95$0, If[LessEqual[y$46$re, -1.26e-170], N[(N[(y$46$re * x$46$re + N[(y$46$im * x$46$im), $MachinePrecision]), $MachinePrecision] / N[(y$46$im * y$46$im), $MachinePrecision]), $MachinePrecision], If[LessEqual[y$46$re, 6e-71], N[(x$46$im / y$46$im), $MachinePrecision], t$95$0]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}\\
\mathbf{if}\;y.re \leq -48:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;y.re \leq -1.26 \cdot 10^{-170}:\\
\;\;\;\;\frac{\mathsf{fma}\left(y.re, x.re, y.im \cdot x.im\right)}{y.im \cdot y.im}\\

\mathbf{elif}\;y.re \leq 6 \cdot 10^{-71}:\\
\;\;\;\;\frac{x.im}{y.im}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y.re < -48 or 6.0000000000000003e-71 < y.re

    1. Initial program 53.1%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around inf

      \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im \cdot y.im}{y.re} + x.re}}{y.re} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{y.im \cdot x.im}}{y.re} + x.re}{y.re} \]
      4. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{y.im \cdot \frac{x.im}{y.re}} + x.re}{y.re} \]
      5. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im}{y.re} \cdot y.im} + x.re}{y.re} \]
      6. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}}{y.re} \]
      7. lower-/.f6482.1

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{x.im}{y.re}}, y.im, x.re\right)}{y.re} \]
    5. Applied rewrites82.1%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}} \]

    if -48 < y.re < -1.26e-170

    1. Initial program 80.8%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around 0

      \[\leadsto \frac{x.re \cdot y.re + x.im \cdot y.im}{\color{blue}{{y.im}^{2}}} \]
    4. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto \frac{x.re \cdot y.re + x.im \cdot y.im}{\color{blue}{y.im \cdot y.im}} \]
      2. lower-*.f6469.8

        \[\leadsto \frac{x.re \cdot y.re + x.im \cdot y.im}{\color{blue}{y.im \cdot y.im}} \]
    5. Applied rewrites69.8%

      \[\leadsto \frac{x.re \cdot y.re + x.im \cdot y.im}{\color{blue}{y.im \cdot y.im}} \]
    6. Step-by-step derivation
      1. lift-+.f64N/A

        \[\leadsto \frac{\color{blue}{x.re \cdot y.re + x.im \cdot y.im}}{y.im \cdot y.im} \]
      2. lift-*.f64N/A

        \[\leadsto \frac{\color{blue}{x.re \cdot y.re} + x.im \cdot y.im}{y.im \cdot y.im} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{y.re \cdot x.re} + x.im \cdot y.im}{y.im \cdot y.im} \]
      4. lower-fma.f6469.8

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(y.re, x.re, x.im \cdot y.im\right)}}{y.im \cdot y.im} \]
      5. lift-*.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(y.re, x.re, \color{blue}{x.im \cdot y.im}\right)}{y.im \cdot y.im} \]
      6. *-commutativeN/A

        \[\leadsto \frac{\mathsf{fma}\left(y.re, x.re, \color{blue}{y.im \cdot x.im}\right)}{y.im \cdot y.im} \]
      7. lower-*.f6469.8

        \[\leadsto \frac{\mathsf{fma}\left(y.re, x.re, \color{blue}{y.im \cdot x.im}\right)}{y.im \cdot y.im} \]
    7. Applied rewrites69.8%

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(y.re, x.re, y.im \cdot x.im\right)}}{y.im \cdot y.im} \]

    if -1.26e-170 < y.re < 6.0000000000000003e-71

    1. Initial program 67.9%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around 0

      \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
    4. Step-by-step derivation
      1. lower-/.f6474.0

        \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
    5. Applied rewrites74.0%

      \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 3: 78.5% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}\\ \mathbf{if}\;y.re \leq -82000:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y.re \leq 4.5 \cdot 10^{-61}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\frac{y.re}{y.im}, x.re, x.im\right)}{y.im}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0 (/ (fma (/ x.im y.re) y.im x.re) y.re)))
   (if (<= y.re -82000.0)
     t_0
     (if (<= y.re 4.5e-61) (/ (fma (/ y.re y.im) x.re x.im) y.im) t_0))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = fma((x_46_im / y_46_re), y_46_im, x_46_re) / y_46_re;
	double tmp;
	if (y_46_re <= -82000.0) {
		tmp = t_0;
	} else if (y_46_re <= 4.5e-61) {
		tmp = fma((y_46_re / y_46_im), x_46_re, x_46_im) / y_46_im;
	} else {
		tmp = t_0;
	}
	return tmp;
}
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = Float64(fma(Float64(x_46_im / y_46_re), y_46_im, x_46_re) / y_46_re)
	tmp = 0.0
	if (y_46_re <= -82000.0)
		tmp = t_0;
	elseif (y_46_re <= 4.5e-61)
		tmp = Float64(fma(Float64(y_46_re / y_46_im), x_46_re, x_46_im) / y_46_im);
	else
		tmp = t_0;
	end
	return tmp
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[(N[(N[(x$46$im / y$46$re), $MachinePrecision] * y$46$im + x$46$re), $MachinePrecision] / y$46$re), $MachinePrecision]}, If[LessEqual[y$46$re, -82000.0], t$95$0, If[LessEqual[y$46$re, 4.5e-61], N[(N[(N[(y$46$re / y$46$im), $MachinePrecision] * x$46$re + x$46$im), $MachinePrecision] / y$46$im), $MachinePrecision], t$95$0]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}\\
\mathbf{if}\;y.re \leq -82000:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;y.re \leq 4.5 \cdot 10^{-61}:\\
\;\;\;\;\frac{\mathsf{fma}\left(\frac{y.re}{y.im}, x.re, x.im\right)}{y.im}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y.re < -82000 or 4.5e-61 < y.re

    1. Initial program 53.1%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around inf

      \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im \cdot y.im}{y.re} + x.re}}{y.re} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{y.im \cdot x.im}}{y.re} + x.re}{y.re} \]
      4. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{y.im \cdot \frac{x.im}{y.re}} + x.re}{y.re} \]
      5. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im}{y.re} \cdot y.im} + x.re}{y.re} \]
      6. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}}{y.re} \]
      7. lower-/.f6482.1

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{x.im}{y.re}}, y.im, x.re\right)}{y.re} \]
    5. Applied rewrites82.1%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}} \]

    if -82000 < y.re < 4.5e-61

    1. Initial program 72.2%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around inf

      \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im \cdot y.im}{y.re} + x.re}}{y.re} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{y.im \cdot x.im}}{y.re} + x.re}{y.re} \]
      4. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{y.im \cdot \frac{x.im}{y.re}} + x.re}{y.re} \]
      5. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im}{y.re} \cdot y.im} + x.re}{y.re} \]
      6. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}}{y.re} \]
      7. lower-/.f6425.5

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{x.im}{y.re}}, y.im, x.re\right)}{y.re} \]
    5. Applied rewrites25.5%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}} \]
    6. Taylor expanded in y.im around inf

      \[\leadsto \color{blue}{\frac{x.im + \frac{x.re \cdot y.re}{y.im}}{y.im}} \]
    7. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.im + \frac{x.re \cdot y.re}{y.im}}{y.im}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.re \cdot y.re}{y.im} + x.im}}{y.im} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{y.re \cdot x.re}}{y.im} + x.im}{y.im} \]
      4. associate-*l/N/A

        \[\leadsto \frac{\color{blue}{\frac{y.re}{y.im} \cdot x.re} + x.im}{y.im} \]
      5. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{y.re}{y.im}, x.re, x.im\right)}}{y.im} \]
      6. lower-/.f6487.4

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{y.re}{y.im}}, x.re, x.im\right)}{y.im} \]
    8. Applied rewrites87.4%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{y.re}{y.im}, x.re, x.im\right)}{y.im}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 4: 77.8% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}\\ \mathbf{if}\;y.re \leq -82000:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y.re \leq 4.5 \cdot 10^{-61}:\\ \;\;\;\;\frac{\mathsf{fma}\left(\frac{x.re}{y.im}, y.re, x.im\right)}{y.im}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0 (/ (fma (/ x.im y.re) y.im x.re) y.re)))
   (if (<= y.re -82000.0)
     t_0
     (if (<= y.re 4.5e-61) (/ (fma (/ x.re y.im) y.re x.im) y.im) t_0))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = fma((x_46_im / y_46_re), y_46_im, x_46_re) / y_46_re;
	double tmp;
	if (y_46_re <= -82000.0) {
		tmp = t_0;
	} else if (y_46_re <= 4.5e-61) {
		tmp = fma((x_46_re / y_46_im), y_46_re, x_46_im) / y_46_im;
	} else {
		tmp = t_0;
	}
	return tmp;
}
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = Float64(fma(Float64(x_46_im / y_46_re), y_46_im, x_46_re) / y_46_re)
	tmp = 0.0
	if (y_46_re <= -82000.0)
		tmp = t_0;
	elseif (y_46_re <= 4.5e-61)
		tmp = Float64(fma(Float64(x_46_re / y_46_im), y_46_re, x_46_im) / y_46_im);
	else
		tmp = t_0;
	end
	return tmp
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[(N[(N[(x$46$im / y$46$re), $MachinePrecision] * y$46$im + x$46$re), $MachinePrecision] / y$46$re), $MachinePrecision]}, If[LessEqual[y$46$re, -82000.0], t$95$0, If[LessEqual[y$46$re, 4.5e-61], N[(N[(N[(x$46$re / y$46$im), $MachinePrecision] * y$46$re + x$46$im), $MachinePrecision] / y$46$im), $MachinePrecision], t$95$0]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}\\
\mathbf{if}\;y.re \leq -82000:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;y.re \leq 4.5 \cdot 10^{-61}:\\
\;\;\;\;\frac{\mathsf{fma}\left(\frac{x.re}{y.im}, y.re, x.im\right)}{y.im}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y.re < -82000 or 4.5e-61 < y.re

    1. Initial program 53.1%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around inf

      \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im \cdot y.im}{y.re} + x.re}}{y.re} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{y.im \cdot x.im}}{y.re} + x.re}{y.re} \]
      4. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{y.im \cdot \frac{x.im}{y.re}} + x.re}{y.re} \]
      5. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im}{y.re} \cdot y.im} + x.re}{y.re} \]
      6. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}}{y.re} \]
      7. lower-/.f6482.1

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{x.im}{y.re}}, y.im, x.re\right)}{y.re} \]
    5. Applied rewrites82.1%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}} \]

    if -82000 < y.re < 4.5e-61

    1. Initial program 72.2%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.im around inf

      \[\leadsto \color{blue}{\frac{x.im + \frac{x.re \cdot y.re}{y.im}}{y.im}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.im + \frac{x.re \cdot y.re}{y.im}}{y.im}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.re \cdot y.re}{y.im} + x.im}}{y.im} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{y.re \cdot x.re}}{y.im} + x.im}{y.im} \]
      4. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{y.re \cdot \frac{x.re}{y.im}} + x.im}{y.im} \]
      5. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.re}{y.im} \cdot y.re} + x.im}{y.im} \]
      6. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{x.re}{y.im}, y.re, x.im\right)}}{y.im} \]
      7. lower-/.f6484.6

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{x.re}{y.im}}, y.re, x.im\right)}{y.im} \]
    5. Applied rewrites84.6%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{x.re}{y.im}, y.re, x.im\right)}{y.im}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 5: 65.8% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y.re \leq -8.8 \cdot 10^{+121}:\\ \;\;\;\;\frac{x.re}{y.re}\\ \mathbf{elif}\;y.re \leq -2.05 \cdot 10^{-60}:\\ \;\;\;\;\frac{y.re}{\mathsf{fma}\left(y.im, y.im, y.re \cdot y.re\right)} \cdot x.re\\ \mathbf{elif}\;y.re \leq 8.2 \cdot 10^{-49}:\\ \;\;\;\;\frac{x.im}{y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{x.re}{y.re}\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (if (<= y.re -8.8e+121)
   (/ x.re y.re)
   (if (<= y.re -2.05e-60)
     (* (/ y.re (fma y.im y.im (* y.re y.re))) x.re)
     (if (<= y.re 8.2e-49) (/ x.im y.im) (/ x.re y.re)))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double tmp;
	if (y_46_re <= -8.8e+121) {
		tmp = x_46_re / y_46_re;
	} else if (y_46_re <= -2.05e-60) {
		tmp = (y_46_re / fma(y_46_im, y_46_im, (y_46_re * y_46_re))) * x_46_re;
	} else if (y_46_re <= 8.2e-49) {
		tmp = x_46_im / y_46_im;
	} else {
		tmp = x_46_re / y_46_re;
	}
	return tmp;
}
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	tmp = 0.0
	if (y_46_re <= -8.8e+121)
		tmp = Float64(x_46_re / y_46_re);
	elseif (y_46_re <= -2.05e-60)
		tmp = Float64(Float64(y_46_re / fma(y_46_im, y_46_im, Float64(y_46_re * y_46_re))) * x_46_re);
	elseif (y_46_re <= 8.2e-49)
		tmp = Float64(x_46_im / y_46_im);
	else
		tmp = Float64(x_46_re / y_46_re);
	end
	return tmp
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := If[LessEqual[y$46$re, -8.8e+121], N[(x$46$re / y$46$re), $MachinePrecision], If[LessEqual[y$46$re, -2.05e-60], N[(N[(y$46$re / N[(y$46$im * y$46$im + N[(y$46$re * y$46$re), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * x$46$re), $MachinePrecision], If[LessEqual[y$46$re, 8.2e-49], N[(x$46$im / y$46$im), $MachinePrecision], N[(x$46$re / y$46$re), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y.re \leq -8.8 \cdot 10^{+121}:\\
\;\;\;\;\frac{x.re}{y.re}\\

\mathbf{elif}\;y.re \leq -2.05 \cdot 10^{-60}:\\
\;\;\;\;\frac{y.re}{\mathsf{fma}\left(y.im, y.im, y.re \cdot y.re\right)} \cdot x.re\\

\mathbf{elif}\;y.re \leq 8.2 \cdot 10^{-49}:\\
\;\;\;\;\frac{x.im}{y.im}\\

\mathbf{else}:\\
\;\;\;\;\frac{x.re}{y.re}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y.re < -8.80000000000000005e121 or 8.2000000000000003e-49 < y.re

    1. Initial program 48.0%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around inf

      \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]
    4. Step-by-step derivation
      1. lower-/.f6468.2

        \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]
    5. Applied rewrites68.2%

      \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]

    if -8.80000000000000005e121 < y.re < -2.05000000000000006e-60

    1. Initial program 78.1%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around inf

      \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.re + \frac{x.im \cdot y.im}{y.re}}{y.re}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im \cdot y.im}{y.re} + x.re}}{y.re} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{y.im \cdot x.im}}{y.re} + x.re}{y.re} \]
      4. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{y.im \cdot \frac{x.im}{y.re}} + x.re}{y.re} \]
      5. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.im}{y.re} \cdot y.im} + x.re}{y.re} \]
      6. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}}{y.re} \]
      7. lower-/.f6456.9

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{x.im}{y.re}}, y.im, x.re\right)}{y.re} \]
    5. Applied rewrites56.9%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{x.im}{y.re}, y.im, x.re\right)}{y.re}} \]
    6. Taylor expanded in x.re around inf

      \[\leadsto \color{blue}{\frac{x.re \cdot y.re}{{y.im}^{2} + {y.re}^{2}}} \]
    7. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{y.re \cdot x.re}}{{y.im}^{2} + {y.re}^{2}} \]
      2. associate-*l/N/A

        \[\leadsto \color{blue}{\frac{y.re}{{y.im}^{2} + {y.re}^{2}} \cdot x.re} \]
      3. lower-*.f64N/A

        \[\leadsto \color{blue}{\frac{y.re}{{y.im}^{2} + {y.re}^{2}} \cdot x.re} \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{y.re}{{y.im}^{2} + {y.re}^{2}}} \cdot x.re \]
      5. unpow2N/A

        \[\leadsto \frac{y.re}{\color{blue}{y.im \cdot y.im} + {y.re}^{2}} \cdot x.re \]
      6. lower-fma.f64N/A

        \[\leadsto \frac{y.re}{\color{blue}{\mathsf{fma}\left(y.im, y.im, {y.re}^{2}\right)}} \cdot x.re \]
      7. unpow2N/A

        \[\leadsto \frac{y.re}{\mathsf{fma}\left(y.im, y.im, \color{blue}{y.re \cdot y.re}\right)} \cdot x.re \]
      8. lower-*.f6469.5

        \[\leadsto \frac{y.re}{\mathsf{fma}\left(y.im, y.im, \color{blue}{y.re \cdot y.re}\right)} \cdot x.re \]
    8. Applied rewrites69.5%

      \[\leadsto \color{blue}{\frac{y.re}{\mathsf{fma}\left(y.im, y.im, y.re \cdot y.re\right)} \cdot x.re} \]

    if -2.05000000000000006e-60 < y.re < 8.2000000000000003e-49

    1. Initial program 69.4%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around 0

      \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
    4. Step-by-step derivation
      1. lower-/.f6470.0

        \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
    5. Applied rewrites70.0%

      \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 6: 65.5% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y.re \leq -7.6 \cdot 10^{+121}:\\ \;\;\;\;\frac{x.re}{y.re}\\ \mathbf{elif}\;y.re \leq -1.02 \cdot 10^{-51}:\\ \;\;\;\;\frac{x.re}{\mathsf{fma}\left(y.im, y.im, y.re \cdot y.re\right)} \cdot y.re\\ \mathbf{elif}\;y.re \leq 8.2 \cdot 10^{-49}:\\ \;\;\;\;\frac{x.im}{y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{x.re}{y.re}\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (if (<= y.re -7.6e+121)
   (/ x.re y.re)
   (if (<= y.re -1.02e-51)
     (* (/ x.re (fma y.im y.im (* y.re y.re))) y.re)
     (if (<= y.re 8.2e-49) (/ x.im y.im) (/ x.re y.re)))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double tmp;
	if (y_46_re <= -7.6e+121) {
		tmp = x_46_re / y_46_re;
	} else if (y_46_re <= -1.02e-51) {
		tmp = (x_46_re / fma(y_46_im, y_46_im, (y_46_re * y_46_re))) * y_46_re;
	} else if (y_46_re <= 8.2e-49) {
		tmp = x_46_im / y_46_im;
	} else {
		tmp = x_46_re / y_46_re;
	}
	return tmp;
}
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	tmp = 0.0
	if (y_46_re <= -7.6e+121)
		tmp = Float64(x_46_re / y_46_re);
	elseif (y_46_re <= -1.02e-51)
		tmp = Float64(Float64(x_46_re / fma(y_46_im, y_46_im, Float64(y_46_re * y_46_re))) * y_46_re);
	elseif (y_46_re <= 8.2e-49)
		tmp = Float64(x_46_im / y_46_im);
	else
		tmp = Float64(x_46_re / y_46_re);
	end
	return tmp
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := If[LessEqual[y$46$re, -7.6e+121], N[(x$46$re / y$46$re), $MachinePrecision], If[LessEqual[y$46$re, -1.02e-51], N[(N[(x$46$re / N[(y$46$im * y$46$im + N[(y$46$re * y$46$re), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * y$46$re), $MachinePrecision], If[LessEqual[y$46$re, 8.2e-49], N[(x$46$im / y$46$im), $MachinePrecision], N[(x$46$re / y$46$re), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y.re \leq -7.6 \cdot 10^{+121}:\\
\;\;\;\;\frac{x.re}{y.re}\\

\mathbf{elif}\;y.re \leq -1.02 \cdot 10^{-51}:\\
\;\;\;\;\frac{x.re}{\mathsf{fma}\left(y.im, y.im, y.re \cdot y.re\right)} \cdot y.re\\

\mathbf{elif}\;y.re \leq 8.2 \cdot 10^{-49}:\\
\;\;\;\;\frac{x.im}{y.im}\\

\mathbf{else}:\\
\;\;\;\;\frac{x.re}{y.re}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y.re < -7.6e121 or 8.2000000000000003e-49 < y.re

    1. Initial program 48.0%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around inf

      \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]
    4. Step-by-step derivation
      1. lower-/.f6468.2

        \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]
    5. Applied rewrites68.2%

      \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]

    if -7.6e121 < y.re < -1.01999999999999998e-51

    1. Initial program 78.1%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in x.re around inf

      \[\leadsto \color{blue}{\frac{x.re \cdot y.re}{{y.im}^{2} + {y.re}^{2}}} \]
    4. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{y.re \cdot x.re}}{{y.im}^{2} + {y.re}^{2}} \]
      2. associate-/l*N/A

        \[\leadsto \color{blue}{y.re \cdot \frac{x.re}{{y.im}^{2} + {y.re}^{2}}} \]
      3. *-commutativeN/A

        \[\leadsto \color{blue}{\frac{x.re}{{y.im}^{2} + {y.re}^{2}} \cdot y.re} \]
      4. lower-*.f64N/A

        \[\leadsto \color{blue}{\frac{x.re}{{y.im}^{2} + {y.re}^{2}} \cdot y.re} \]
      5. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.re}{{y.im}^{2} + {y.re}^{2}}} \cdot y.re \]
      6. unpow2N/A

        \[\leadsto \frac{x.re}{\color{blue}{y.im \cdot y.im} + {y.re}^{2}} \cdot y.re \]
      7. lower-fma.f64N/A

        \[\leadsto \frac{x.re}{\color{blue}{\mathsf{fma}\left(y.im, y.im, {y.re}^{2}\right)}} \cdot y.re \]
      8. unpow2N/A

        \[\leadsto \frac{x.re}{\mathsf{fma}\left(y.im, y.im, \color{blue}{y.re \cdot y.re}\right)} \cdot y.re \]
      9. lower-*.f6468.0

        \[\leadsto \frac{x.re}{\mathsf{fma}\left(y.im, y.im, \color{blue}{y.re \cdot y.re}\right)} \cdot y.re \]
    5. Applied rewrites68.0%

      \[\leadsto \color{blue}{\frac{x.re}{\mathsf{fma}\left(y.im, y.im, y.re \cdot y.re\right)} \cdot y.re} \]

    if -1.01999999999999998e-51 < y.re < 8.2000000000000003e-49

    1. Initial program 69.4%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around 0

      \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
    4. Step-by-step derivation
      1. lower-/.f6470.0

        \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
    5. Applied rewrites70.0%

      \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 7: 63.6% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y.re \leq -300000:\\ \;\;\;\;\frac{x.re}{y.re}\\ \mathbf{elif}\;y.re \leq -2.8 \cdot 10^{-51}:\\ \;\;\;\;\frac{x.re}{y.im} \cdot \frac{y.re}{y.im}\\ \mathbf{elif}\;y.re \leq 8.2 \cdot 10^{-49}:\\ \;\;\;\;\frac{x.im}{y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{x.re}{y.re}\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (if (<= y.re -300000.0)
   (/ x.re y.re)
   (if (<= y.re -2.8e-51)
     (* (/ x.re y.im) (/ y.re y.im))
     (if (<= y.re 8.2e-49) (/ x.im y.im) (/ x.re y.re)))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double tmp;
	if (y_46_re <= -300000.0) {
		tmp = x_46_re / y_46_re;
	} else if (y_46_re <= -2.8e-51) {
		tmp = (x_46_re / y_46_im) * (y_46_re / y_46_im);
	} else if (y_46_re <= 8.2e-49) {
		tmp = x_46_im / y_46_im;
	} else {
		tmp = x_46_re / y_46_re;
	}
	return tmp;
}
real(8) function code(x_46re, x_46im, y_46re, y_46im)
    real(8), intent (in) :: x_46re
    real(8), intent (in) :: x_46im
    real(8), intent (in) :: y_46re
    real(8), intent (in) :: y_46im
    real(8) :: tmp
    if (y_46re <= (-300000.0d0)) then
        tmp = x_46re / y_46re
    else if (y_46re <= (-2.8d-51)) then
        tmp = (x_46re / y_46im) * (y_46re / y_46im)
    else if (y_46re <= 8.2d-49) then
        tmp = x_46im / y_46im
    else
        tmp = x_46re / y_46re
    end if
    code = tmp
end function
public static double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double tmp;
	if (y_46_re <= -300000.0) {
		tmp = x_46_re / y_46_re;
	} else if (y_46_re <= -2.8e-51) {
		tmp = (x_46_re / y_46_im) * (y_46_re / y_46_im);
	} else if (y_46_re <= 8.2e-49) {
		tmp = x_46_im / y_46_im;
	} else {
		tmp = x_46_re / y_46_re;
	}
	return tmp;
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	tmp = 0
	if y_46_re <= -300000.0:
		tmp = x_46_re / y_46_re
	elif y_46_re <= -2.8e-51:
		tmp = (x_46_re / y_46_im) * (y_46_re / y_46_im)
	elif y_46_re <= 8.2e-49:
		tmp = x_46_im / y_46_im
	else:
		tmp = x_46_re / y_46_re
	return tmp
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	tmp = 0.0
	if (y_46_re <= -300000.0)
		tmp = Float64(x_46_re / y_46_re);
	elseif (y_46_re <= -2.8e-51)
		tmp = Float64(Float64(x_46_re / y_46_im) * Float64(y_46_re / y_46_im));
	elseif (y_46_re <= 8.2e-49)
		tmp = Float64(x_46_im / y_46_im);
	else
		tmp = Float64(x_46_re / y_46_re);
	end
	return tmp
end
function tmp_2 = code(x_46_re, x_46_im, y_46_re, y_46_im)
	tmp = 0.0;
	if (y_46_re <= -300000.0)
		tmp = x_46_re / y_46_re;
	elseif (y_46_re <= -2.8e-51)
		tmp = (x_46_re / y_46_im) * (y_46_re / y_46_im);
	elseif (y_46_re <= 8.2e-49)
		tmp = x_46_im / y_46_im;
	else
		tmp = x_46_re / y_46_re;
	end
	tmp_2 = tmp;
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := If[LessEqual[y$46$re, -300000.0], N[(x$46$re / y$46$re), $MachinePrecision], If[LessEqual[y$46$re, -2.8e-51], N[(N[(x$46$re / y$46$im), $MachinePrecision] * N[(y$46$re / y$46$im), $MachinePrecision]), $MachinePrecision], If[LessEqual[y$46$re, 8.2e-49], N[(x$46$im / y$46$im), $MachinePrecision], N[(x$46$re / y$46$re), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y.re \leq -300000:\\
\;\;\;\;\frac{x.re}{y.re}\\

\mathbf{elif}\;y.re \leq -2.8 \cdot 10^{-51}:\\
\;\;\;\;\frac{x.re}{y.im} \cdot \frac{y.re}{y.im}\\

\mathbf{elif}\;y.re \leq 8.2 \cdot 10^{-49}:\\
\;\;\;\;\frac{x.im}{y.im}\\

\mathbf{else}:\\
\;\;\;\;\frac{x.re}{y.re}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y.re < -3e5 or 8.2000000000000003e-49 < y.re

    1. Initial program 52.5%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.re around inf

      \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]
    4. Step-by-step derivation
      1. lower-/.f6465.6

        \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]
    5. Applied rewrites65.6%

      \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]

    if -3e5 < y.re < -2.8e-51

    1. Initial program 93.3%

      \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Add Preprocessing
    3. Taylor expanded in y.im around inf

      \[\leadsto \color{blue}{\frac{x.im + \frac{x.re \cdot y.re}{y.im}}{y.im}} \]
    4. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{x.im + \frac{x.re \cdot y.re}{y.im}}{y.im}} \]
      2. +-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.re \cdot y.re}{y.im} + x.im}}{y.im} \]
      3. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{y.re \cdot x.re}}{y.im} + x.im}{y.im} \]
      4. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{y.re \cdot \frac{x.re}{y.im}} + x.im}{y.im} \]
      5. *-commutativeN/A

        \[\leadsto \frac{\color{blue}{\frac{x.re}{y.im} \cdot y.re} + x.im}{y.im} \]
      6. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{x.re}{y.im}, y.re, x.im\right)}}{y.im} \]
      7. lower-/.f6474.3

        \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{x.re}{y.im}}, y.re, x.im\right)}{y.im} \]
    5. Applied rewrites74.3%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{x.re}{y.im}, y.re, x.im\right)}{y.im}} \]
    6. Taylor expanded in x.re around inf

      \[\leadsto \frac{x.re \cdot y.re}{\color{blue}{{y.im}^{2}}} \]
    7. Step-by-step derivation
      1. Applied rewrites67.7%

        \[\leadsto \frac{\frac{x.re}{y.im}}{y.im} \cdot \color{blue}{y.re} \]
      2. Step-by-step derivation
        1. Applied rewrites67.7%

          \[\leadsto \frac{y.re}{y.im} \cdot \frac{x.re}{\color{blue}{y.im}} \]

        if -2.8e-51 < y.re < 8.2000000000000003e-49

        1. Initial program 69.4%

          \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
        2. Add Preprocessing
        3. Taylor expanded in y.re around 0

          \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
        4. Step-by-step derivation
          1. lower-/.f6470.0

            \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
        5. Applied rewrites70.0%

          \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
      3. Recombined 3 regimes into one program.
      4. Final simplification67.3%

        \[\leadsto \begin{array}{l} \mathbf{if}\;y.re \leq -300000:\\ \;\;\;\;\frac{x.re}{y.re}\\ \mathbf{elif}\;y.re \leq -2.8 \cdot 10^{-51}:\\ \;\;\;\;\frac{x.re}{y.im} \cdot \frac{y.re}{y.im}\\ \mathbf{elif}\;y.re \leq 8.2 \cdot 10^{-49}:\\ \;\;\;\;\frac{x.im}{y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{x.re}{y.re}\\ \end{array} \]
      5. Add Preprocessing

      Alternative 8: 63.4% accurate, 1.1× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y.re \leq -300000:\\ \;\;\;\;\frac{x.re}{y.re}\\ \mathbf{elif}\;y.re \leq -3.6 \cdot 10^{-51}:\\ \;\;\;\;\frac{y.re}{y.im \cdot y.im} \cdot x.re\\ \mathbf{elif}\;y.re \leq 8.2 \cdot 10^{-49}:\\ \;\;\;\;\frac{x.im}{y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{x.re}{y.re}\\ \end{array} \end{array} \]
      (FPCore (x.re x.im y.re y.im)
       :precision binary64
       (if (<= y.re -300000.0)
         (/ x.re y.re)
         (if (<= y.re -3.6e-51)
           (* (/ y.re (* y.im y.im)) x.re)
           (if (<= y.re 8.2e-49) (/ x.im y.im) (/ x.re y.re)))))
      double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
      	double tmp;
      	if (y_46_re <= -300000.0) {
      		tmp = x_46_re / y_46_re;
      	} else if (y_46_re <= -3.6e-51) {
      		tmp = (y_46_re / (y_46_im * y_46_im)) * x_46_re;
      	} else if (y_46_re <= 8.2e-49) {
      		tmp = x_46_im / y_46_im;
      	} else {
      		tmp = x_46_re / y_46_re;
      	}
      	return tmp;
      }
      
      real(8) function code(x_46re, x_46im, y_46re, y_46im)
          real(8), intent (in) :: x_46re
          real(8), intent (in) :: x_46im
          real(8), intent (in) :: y_46re
          real(8), intent (in) :: y_46im
          real(8) :: tmp
          if (y_46re <= (-300000.0d0)) then
              tmp = x_46re / y_46re
          else if (y_46re <= (-3.6d-51)) then
              tmp = (y_46re / (y_46im * y_46im)) * x_46re
          else if (y_46re <= 8.2d-49) then
              tmp = x_46im / y_46im
          else
              tmp = x_46re / y_46re
          end if
          code = tmp
      end function
      
      public static double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
      	double tmp;
      	if (y_46_re <= -300000.0) {
      		tmp = x_46_re / y_46_re;
      	} else if (y_46_re <= -3.6e-51) {
      		tmp = (y_46_re / (y_46_im * y_46_im)) * x_46_re;
      	} else if (y_46_re <= 8.2e-49) {
      		tmp = x_46_im / y_46_im;
      	} else {
      		tmp = x_46_re / y_46_re;
      	}
      	return tmp;
      }
      
      def code(x_46_re, x_46_im, y_46_re, y_46_im):
      	tmp = 0
      	if y_46_re <= -300000.0:
      		tmp = x_46_re / y_46_re
      	elif y_46_re <= -3.6e-51:
      		tmp = (y_46_re / (y_46_im * y_46_im)) * x_46_re
      	elif y_46_re <= 8.2e-49:
      		tmp = x_46_im / y_46_im
      	else:
      		tmp = x_46_re / y_46_re
      	return tmp
      
      function code(x_46_re, x_46_im, y_46_re, y_46_im)
      	tmp = 0.0
      	if (y_46_re <= -300000.0)
      		tmp = Float64(x_46_re / y_46_re);
      	elseif (y_46_re <= -3.6e-51)
      		tmp = Float64(Float64(y_46_re / Float64(y_46_im * y_46_im)) * x_46_re);
      	elseif (y_46_re <= 8.2e-49)
      		tmp = Float64(x_46_im / y_46_im);
      	else
      		tmp = Float64(x_46_re / y_46_re);
      	end
      	return tmp
      end
      
      function tmp_2 = code(x_46_re, x_46_im, y_46_re, y_46_im)
      	tmp = 0.0;
      	if (y_46_re <= -300000.0)
      		tmp = x_46_re / y_46_re;
      	elseif (y_46_re <= -3.6e-51)
      		tmp = (y_46_re / (y_46_im * y_46_im)) * x_46_re;
      	elseif (y_46_re <= 8.2e-49)
      		tmp = x_46_im / y_46_im;
      	else
      		tmp = x_46_re / y_46_re;
      	end
      	tmp_2 = tmp;
      end
      
      code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := If[LessEqual[y$46$re, -300000.0], N[(x$46$re / y$46$re), $MachinePrecision], If[LessEqual[y$46$re, -3.6e-51], N[(N[(y$46$re / N[(y$46$im * y$46$im), $MachinePrecision]), $MachinePrecision] * x$46$re), $MachinePrecision], If[LessEqual[y$46$re, 8.2e-49], N[(x$46$im / y$46$im), $MachinePrecision], N[(x$46$re / y$46$re), $MachinePrecision]]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;y.re \leq -300000:\\
      \;\;\;\;\frac{x.re}{y.re}\\
      
      \mathbf{elif}\;y.re \leq -3.6 \cdot 10^{-51}:\\
      \;\;\;\;\frac{y.re}{y.im \cdot y.im} \cdot x.re\\
      
      \mathbf{elif}\;y.re \leq 8.2 \cdot 10^{-49}:\\
      \;\;\;\;\frac{x.im}{y.im}\\
      
      \mathbf{else}:\\
      \;\;\;\;\frac{x.re}{y.re}\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if y.re < -3e5 or 8.2000000000000003e-49 < y.re

        1. Initial program 52.5%

          \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
        2. Add Preprocessing
        3. Taylor expanded in y.re around inf

          \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]
        4. Step-by-step derivation
          1. lower-/.f6465.6

            \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]
        5. Applied rewrites65.6%

          \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]

        if -3e5 < y.re < -3.6e-51

        1. Initial program 93.3%

          \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
        2. Add Preprocessing
        3. Taylor expanded in y.im around inf

          \[\leadsto \color{blue}{\frac{x.im + \frac{x.re \cdot y.re}{y.im}}{y.im}} \]
        4. Step-by-step derivation
          1. lower-/.f64N/A

            \[\leadsto \color{blue}{\frac{x.im + \frac{x.re \cdot y.re}{y.im}}{y.im}} \]
          2. +-commutativeN/A

            \[\leadsto \frac{\color{blue}{\frac{x.re \cdot y.re}{y.im} + x.im}}{y.im} \]
          3. *-commutativeN/A

            \[\leadsto \frac{\frac{\color{blue}{y.re \cdot x.re}}{y.im} + x.im}{y.im} \]
          4. associate-/l*N/A

            \[\leadsto \frac{\color{blue}{y.re \cdot \frac{x.re}{y.im}} + x.im}{y.im} \]
          5. *-commutativeN/A

            \[\leadsto \frac{\color{blue}{\frac{x.re}{y.im} \cdot y.re} + x.im}{y.im} \]
          6. lower-fma.f64N/A

            \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{x.re}{y.im}, y.re, x.im\right)}}{y.im} \]
          7. lower-/.f6474.3

            \[\leadsto \frac{\mathsf{fma}\left(\color{blue}{\frac{x.re}{y.im}}, y.re, x.im\right)}{y.im} \]
        5. Applied rewrites74.3%

          \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{x.re}{y.im}, y.re, x.im\right)}{y.im}} \]
        6. Taylor expanded in x.re around inf

          \[\leadsto \frac{x.re \cdot y.re}{\color{blue}{{y.im}^{2}}} \]
        7. Step-by-step derivation
          1. Applied rewrites67.7%

            \[\leadsto \frac{\frac{x.re}{y.im}}{y.im} \cdot \color{blue}{y.re} \]
          2. Taylor expanded in x.re around 0

            \[\leadsto \frac{x.re \cdot y.re}{{y.im}^{\color{blue}{2}}} \]
          3. Step-by-step derivation
            1. Applied rewrites61.2%

              \[\leadsto \frac{y.re}{y.im \cdot y.im} \cdot x.re \]

            if -3.6e-51 < y.re < 8.2000000000000003e-49

            1. Initial program 69.4%

              \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
            2. Add Preprocessing
            3. Taylor expanded in y.re around 0

              \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
            4. Step-by-step derivation
              1. lower-/.f6470.0

                \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
            5. Applied rewrites70.0%

              \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
          4. Recombined 3 regimes into one program.
          5. Add Preprocessing

          Alternative 9: 64.3% accurate, 1.6× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y.re \leq -7.9 \cdot 10^{-38}:\\ \;\;\;\;\frac{x.re}{y.re}\\ \mathbf{elif}\;y.re \leq 8.2 \cdot 10^{-49}:\\ \;\;\;\;\frac{x.im}{y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{x.re}{y.re}\\ \end{array} \end{array} \]
          (FPCore (x.re x.im y.re y.im)
           :precision binary64
           (if (<= y.re -7.9e-38)
             (/ x.re y.re)
             (if (<= y.re 8.2e-49) (/ x.im y.im) (/ x.re y.re))))
          double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
          	double tmp;
          	if (y_46_re <= -7.9e-38) {
          		tmp = x_46_re / y_46_re;
          	} else if (y_46_re <= 8.2e-49) {
          		tmp = x_46_im / y_46_im;
          	} else {
          		tmp = x_46_re / y_46_re;
          	}
          	return tmp;
          }
          
          real(8) function code(x_46re, x_46im, y_46re, y_46im)
              real(8), intent (in) :: x_46re
              real(8), intent (in) :: x_46im
              real(8), intent (in) :: y_46re
              real(8), intent (in) :: y_46im
              real(8) :: tmp
              if (y_46re <= (-7.9d-38)) then
                  tmp = x_46re / y_46re
              else if (y_46re <= 8.2d-49) then
                  tmp = x_46im / y_46im
              else
                  tmp = x_46re / y_46re
              end if
              code = tmp
          end function
          
          public static double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
          	double tmp;
          	if (y_46_re <= -7.9e-38) {
          		tmp = x_46_re / y_46_re;
          	} else if (y_46_re <= 8.2e-49) {
          		tmp = x_46_im / y_46_im;
          	} else {
          		tmp = x_46_re / y_46_re;
          	}
          	return tmp;
          }
          
          def code(x_46_re, x_46_im, y_46_re, y_46_im):
          	tmp = 0
          	if y_46_re <= -7.9e-38:
          		tmp = x_46_re / y_46_re
          	elif y_46_re <= 8.2e-49:
          		tmp = x_46_im / y_46_im
          	else:
          		tmp = x_46_re / y_46_re
          	return tmp
          
          function code(x_46_re, x_46_im, y_46_re, y_46_im)
          	tmp = 0.0
          	if (y_46_re <= -7.9e-38)
          		tmp = Float64(x_46_re / y_46_re);
          	elseif (y_46_re <= 8.2e-49)
          		tmp = Float64(x_46_im / y_46_im);
          	else
          		tmp = Float64(x_46_re / y_46_re);
          	end
          	return tmp
          end
          
          function tmp_2 = code(x_46_re, x_46_im, y_46_re, y_46_im)
          	tmp = 0.0;
          	if (y_46_re <= -7.9e-38)
          		tmp = x_46_re / y_46_re;
          	elseif (y_46_re <= 8.2e-49)
          		tmp = x_46_im / y_46_im;
          	else
          		tmp = x_46_re / y_46_re;
          	end
          	tmp_2 = tmp;
          end
          
          code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := If[LessEqual[y$46$re, -7.9e-38], N[(x$46$re / y$46$re), $MachinePrecision], If[LessEqual[y$46$re, 8.2e-49], N[(x$46$im / y$46$im), $MachinePrecision], N[(x$46$re / y$46$re), $MachinePrecision]]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;y.re \leq -7.9 \cdot 10^{-38}:\\
          \;\;\;\;\frac{x.re}{y.re}\\
          
          \mathbf{elif}\;y.re \leq 8.2 \cdot 10^{-49}:\\
          \;\;\;\;\frac{x.im}{y.im}\\
          
          \mathbf{else}:\\
          \;\;\;\;\frac{x.re}{y.re}\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if y.re < -7.8999999999999998e-38 or 8.2000000000000003e-49 < y.re

            1. Initial program 55.2%

              \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
            2. Add Preprocessing
            3. Taylor expanded in y.re around inf

              \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]
            4. Step-by-step derivation
              1. lower-/.f6463.3

                \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]
            5. Applied rewrites63.3%

              \[\leadsto \color{blue}{\frac{x.re}{y.re}} \]

            if -7.8999999999999998e-38 < y.re < 8.2000000000000003e-49

            1. Initial program 70.3%

              \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
            2. Add Preprocessing
            3. Taylor expanded in y.re around 0

              \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
            4. Step-by-step derivation
              1. lower-/.f6466.9

                \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
            5. Applied rewrites66.9%

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

          Alternative 10: 42.8% accurate, 3.2× speedup?

          \[\begin{array}{l} \\ \frac{x.im}{y.im} \end{array} \]
          (FPCore (x.re x.im y.re y.im) :precision binary64 (/ x.im y.im))
          double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
          	return x_46_im / y_46_im;
          }
          
          real(8) function code(x_46re, x_46im, y_46re, y_46im)
              real(8), intent (in) :: x_46re
              real(8), intent (in) :: x_46im
              real(8), intent (in) :: y_46re
              real(8), intent (in) :: y_46im
              code = x_46im / y_46im
          end function
          
          public static double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
          	return x_46_im / y_46_im;
          }
          
          def code(x_46_re, x_46_im, y_46_re, y_46_im):
          	return x_46_im / y_46_im
          
          function code(x_46_re, x_46_im, y_46_re, y_46_im)
          	return Float64(x_46_im / y_46_im)
          end
          
          function tmp = code(x_46_re, x_46_im, y_46_re, y_46_im)
          	tmp = x_46_im / y_46_im;
          end
          
          code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := N[(x$46$im / y$46$im), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \frac{x.im}{y.im}
          \end{array}
          
          Derivation
          1. Initial program 61.0%

            \[\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
          2. Add Preprocessing
          3. Taylor expanded in y.re around 0

            \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
          4. Step-by-step derivation
            1. lower-/.f6438.3

              \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
          5. Applied rewrites38.3%

            \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
          6. Add Preprocessing

          Reproduce

          ?
          herbie shell --seed 2024295 
          (FPCore (x.re x.im y.re y.im)
            :name "_divideComplex, real part"
            :precision binary64
            (/ (+ (* x.re y.re) (* x.im y.im)) (+ (* y.re y.re) (* y.im y.im))))