_divideComplex, imaginary part

Percentage Accurate: 61.6% → 93.3%
Time: 14.9s
Alternatives: 14
Speedup: 1.8×

Specification

?
\[\begin{array}{l} \\ \frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (/ (- (* x.im y.re) (* x.re 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_im * y_46_re) - (x_46_re * 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_46im * y_46re) - (x_46re * 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_im * y_46_re) - (x_46_re * 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_im * y_46_re) - (x_46_re * 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_im * y_46_re) - Float64(x_46_re * 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_im * y_46_re) - (x_46_re * 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$46$im * y$46$re), $MachinePrecision] - N[(x$46$re * 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.im \cdot y.re - x.re \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 14 alternatives:

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

Initial Program: 61.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (/ (- (* x.im y.re) (* x.re 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_im * y_46_re) - (x_46_re * 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_46im * y_46re) - (x_46re * 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_im * y_46_re) - (x_46_re * 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_im * y_46_re) - (x_46_re * 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_im * y_46_re) - Float64(x_46_re * 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_im * y_46_re) - (x_46_re * 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$46$im * y$46$re), $MachinePrecision] - N[(x$46$re * 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.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}
\end{array}

Alternative 1: 93.3% accurate, 0.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}\\ t_1 := \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}\\ \mathbf{if}\;y.im \leq -1.5 \cdot 10^{+106}:\\ \;\;\;\;\mathsf{fma}\left(t_0, t_1, \frac{-x.re}{y.im}\right)\\ \mathbf{elif}\;y.im \leq 3.4 \cdot 10^{-298}:\\ \;\;\;\;\mathsf{fma}\left(t_0, t_1, \frac{-x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(t_0, t_1, \frac{-x.re}{{\left(\frac{\mathsf{hypot}\left(y.re, y.im\right)}{\sqrt{y.im}}\right)}^{2}}\right)\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0 (/ y.re (hypot y.re y.im))) (t_1 (/ x.im (hypot y.re y.im))))
   (if (<= y.im -1.5e+106)
     (fma t_0 t_1 (/ (- x.re) y.im))
     (if (<= y.im 3.4e-298)
       (fma t_0 t_1 (/ (- x.re) (/ (pow (hypot y.re y.im) 2.0) y.im)))
       (fma
        t_0
        t_1
        (/ (- x.re) (pow (/ (hypot y.re y.im) (sqrt y.im)) 2.0)))))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = y_46_re / hypot(y_46_re, y_46_im);
	double t_1 = x_46_im / hypot(y_46_re, y_46_im);
	double tmp;
	if (y_46_im <= -1.5e+106) {
		tmp = fma(t_0, t_1, (-x_46_re / y_46_im));
	} else if (y_46_im <= 3.4e-298) {
		tmp = fma(t_0, t_1, (-x_46_re / (pow(hypot(y_46_re, y_46_im), 2.0) / y_46_im)));
	} else {
		tmp = fma(t_0, t_1, (-x_46_re / pow((hypot(y_46_re, y_46_im) / sqrt(y_46_im)), 2.0)));
	}
	return tmp;
}
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = Float64(y_46_re / hypot(y_46_re, y_46_im))
	t_1 = Float64(x_46_im / hypot(y_46_re, y_46_im))
	tmp = 0.0
	if (y_46_im <= -1.5e+106)
		tmp = fma(t_0, t_1, Float64(Float64(-x_46_re) / y_46_im));
	elseif (y_46_im <= 3.4e-298)
		tmp = fma(t_0, t_1, Float64(Float64(-x_46_re) / Float64((hypot(y_46_re, y_46_im) ^ 2.0) / y_46_im)));
	else
		tmp = fma(t_0, t_1, Float64(Float64(-x_46_re) / (Float64(hypot(y_46_re, y_46_im) / sqrt(y_46_im)) ^ 2.0)));
	end
	return tmp
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[(y$46$re / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(x$46$im / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y$46$im, -1.5e+106], N[(t$95$0 * t$95$1 + N[((-x$46$re) / y$46$im), $MachinePrecision]), $MachinePrecision], If[LessEqual[y$46$im, 3.4e-298], N[(t$95$0 * t$95$1 + N[((-x$46$re) / N[(N[Power[N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision], 2.0], $MachinePrecision] / y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(t$95$0 * t$95$1 + N[((-x$46$re) / N[Power[N[(N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision] / N[Sqrt[y$46$im], $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}\\
t_1 := \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}\\
\mathbf{if}\;y.im \leq -1.5 \cdot 10^{+106}:\\
\;\;\;\;\mathsf{fma}\left(t_0, t_1, \frac{-x.re}{y.im}\right)\\

\mathbf{elif}\;y.im \leq 3.4 \cdot 10^{-298}:\\
\;\;\;\;\mathsf{fma}\left(t_0, t_1, \frac{-x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(t_0, t_1, \frac{-x.re}{{\left(\frac{\mathsf{hypot}\left(y.re, y.im\right)}{\sqrt{y.im}}\right)}^{2}}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y.im < -1.5e106

    1. Initial program 41.5%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. div-sub41.5%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} - \frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}} \]
      2. sub-neg41.5%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      3. *-commutative41.5%

        \[\leadsto \frac{\color{blue}{y.re \cdot x.im}}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      4. add-sqr-sqrt41.5%

        \[\leadsto \frac{y.re \cdot x.im}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      5. times-frac41.8%

        \[\leadsto \color{blue}{\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      6. fma-def41.8%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      7. hypot-def41.8%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      8. hypot-def49.4%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      9. associate-/l*53.3%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\color{blue}{\frac{x.re}{\frac{y.re \cdot y.re + y.im \cdot y.im}{y.im}}}\right) \]
      10. add-sqr-sqrt53.3%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}}{y.im}}\right) \]
      11. pow253.3%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{{\left(\sqrt{y.re \cdot y.re + y.im \cdot y.im}\right)}^{2}}}{y.im}}\right) \]
      12. hypot-def53.3%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\color{blue}{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}}^{2}}{y.im}}\right) \]
    3. Applied egg-rr53.3%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}\right)} \]
    4. Taylor expanded in y.re around 0 97.6%

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

    if -1.5e106 < y.im < 3.4e-298

    1. Initial program 81.7%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. div-sub80.5%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} - \frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}} \]
      2. sub-neg80.5%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      3. *-commutative80.5%

        \[\leadsto \frac{\color{blue}{y.re \cdot x.im}}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      4. add-sqr-sqrt80.5%

        \[\leadsto \frac{y.re \cdot x.im}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      5. times-frac84.4%

        \[\leadsto \color{blue}{\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      6. fma-def84.4%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      7. hypot-def84.5%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      8. hypot-def96.5%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      9. associate-/l*97.6%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\color{blue}{\frac{x.re}{\frac{y.re \cdot y.re + y.im \cdot y.im}{y.im}}}\right) \]
      10. add-sqr-sqrt97.6%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}}{y.im}}\right) \]
      11. pow297.6%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{{\left(\sqrt{y.re \cdot y.re + y.im \cdot y.im}\right)}^{2}}}{y.im}}\right) \]
      12. hypot-def97.6%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\color{blue}{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}}^{2}}{y.im}}\right) \]
    3. Applied egg-rr97.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}\right)} \]

    if 3.4e-298 < y.im

    1. Initial program 65.2%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. div-sub62.8%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} - \frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}} \]
      2. sub-neg62.8%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      3. *-commutative62.8%

        \[\leadsto \frac{\color{blue}{y.re \cdot x.im}}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      4. add-sqr-sqrt62.8%

        \[\leadsto \frac{y.re \cdot x.im}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      5. times-frac63.0%

        \[\leadsto \color{blue}{\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      6. fma-def63.0%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      7. hypot-def63.0%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      8. hypot-def78.0%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      9. associate-/l*80.5%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\color{blue}{\frac{x.re}{\frac{y.re \cdot y.re + y.im \cdot y.im}{y.im}}}\right) \]
      10. add-sqr-sqrt80.5%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}}{y.im}}\right) \]
      11. pow280.5%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{{\left(\sqrt{y.re \cdot y.re + y.im \cdot y.im}\right)}^{2}}}{y.im}}\right) \]
      12. hypot-def80.5%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\color{blue}{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}}^{2}}{y.im}}\right) \]
    3. Applied egg-rr80.5%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}\right)} \]
    4. Step-by-step derivation
      1. unpow280.5%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right) \cdot \mathsf{hypot}\left(y.re, y.im\right)}}{y.im}}\right) \]
      2. add-sqr-sqrt80.3%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\mathsf{hypot}\left(y.re, y.im\right) \cdot \mathsf{hypot}\left(y.re, y.im\right)}{\color{blue}{\sqrt{y.im} \cdot \sqrt{y.im}}}}\right) \]
      3. times-frac94.5%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\color{blue}{\frac{\mathsf{hypot}\left(y.re, y.im\right)}{\sqrt{y.im}} \cdot \frac{\mathsf{hypot}\left(y.re, y.im\right)}{\sqrt{y.im}}}}\right) \]
    5. Applied egg-rr94.5%

      \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\color{blue}{\frac{\mathsf{hypot}\left(y.re, y.im\right)}{\sqrt{y.im}} \cdot \frac{\mathsf{hypot}\left(y.re, y.im\right)}{\sqrt{y.im}}}}\right) \]
    6. Step-by-step derivation
      1. unpow294.5%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\color{blue}{{\left(\frac{\mathsf{hypot}\left(y.re, y.im\right)}{\sqrt{y.im}}\right)}^{2}}}\right) \]
    7. Simplified94.5%

      \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\color{blue}{{\left(\frac{\mathsf{hypot}\left(y.re, y.im\right)}{\sqrt{y.im}}\right)}^{2}}}\right) \]
  3. Recombined 3 regimes into one program.
  4. Final simplification96.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y.im \leq -1.5 \cdot 10^{+106}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{-x.re}{y.im}\right)\\ \mathbf{elif}\;y.im \leq 3.4 \cdot 10^{-298}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{-x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{-x.re}{{\left(\frac{\mathsf{hypot}\left(y.re, y.im\right)}{\sqrt{y.im}}\right)}^{2}}\right)\\ \end{array} \]

Alternative 2: 89.4% accurate, 0.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := {\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}\\ t_1 := \frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}\\ t_2 := \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}\\ t_3 := \mathsf{fma}\left(t_1, t_2, \frac{-x.re}{y.im}\right)\\ t_4 := \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)}\\ \mathbf{if}\;y.im \leq -8 \cdot 10^{+105}:\\ \;\;\;\;t_3\\ \mathbf{elif}\;y.im \leq 7 \cdot 10^{-302}:\\ \;\;\;\;\mathsf{fma}\left(t_1, t_2, \frac{-x.re}{\frac{t_0}{y.im}}\right)\\ \mathbf{elif}\;y.im \leq 7.5 \cdot 10^{-147}:\\ \;\;\;\;t_4 \cdot \frac{y.re \cdot x.im - y.im \cdot x.re}{\mathsf{hypot}\left(y.re, y.im\right)}\\ \mathbf{elif}\;y.im \leq 1.18 \cdot 10^{+176}:\\ \;\;\;\;t_4 \cdot \frac{y.re}{\frac{\mathsf{hypot}\left(y.re, y.im\right)}{x.im}} - y.im \cdot \frac{x.re}{t_0}\\ \mathbf{else}:\\ \;\;\;\;t_3\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0 (pow (hypot y.re y.im) 2.0))
        (t_1 (/ y.re (hypot y.re y.im)))
        (t_2 (/ x.im (hypot y.re y.im)))
        (t_3 (fma t_1 t_2 (/ (- x.re) y.im)))
        (t_4 (/ 1.0 (hypot y.re y.im))))
   (if (<= y.im -8e+105)
     t_3
     (if (<= y.im 7e-302)
       (fma t_1 t_2 (/ (- x.re) (/ t_0 y.im)))
       (if (<= y.im 7.5e-147)
         (* t_4 (/ (- (* y.re x.im) (* y.im x.re)) (hypot y.re y.im)))
         (if (<= y.im 1.18e+176)
           (-
            (* t_4 (/ y.re (/ (hypot y.re y.im) x.im)))
            (* y.im (/ x.re t_0)))
           t_3))))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = pow(hypot(y_46_re, y_46_im), 2.0);
	double t_1 = y_46_re / hypot(y_46_re, y_46_im);
	double t_2 = x_46_im / hypot(y_46_re, y_46_im);
	double t_3 = fma(t_1, t_2, (-x_46_re / y_46_im));
	double t_4 = 1.0 / hypot(y_46_re, y_46_im);
	double tmp;
	if (y_46_im <= -8e+105) {
		tmp = t_3;
	} else if (y_46_im <= 7e-302) {
		tmp = fma(t_1, t_2, (-x_46_re / (t_0 / y_46_im)));
	} else if (y_46_im <= 7.5e-147) {
		tmp = t_4 * (((y_46_re * x_46_im) - (y_46_im * x_46_re)) / hypot(y_46_re, y_46_im));
	} else if (y_46_im <= 1.18e+176) {
		tmp = (t_4 * (y_46_re / (hypot(y_46_re, y_46_im) / x_46_im))) - (y_46_im * (x_46_re / t_0));
	} else {
		tmp = t_3;
	}
	return tmp;
}
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = hypot(y_46_re, y_46_im) ^ 2.0
	t_1 = Float64(y_46_re / hypot(y_46_re, y_46_im))
	t_2 = Float64(x_46_im / hypot(y_46_re, y_46_im))
	t_3 = fma(t_1, t_2, Float64(Float64(-x_46_re) / y_46_im))
	t_4 = Float64(1.0 / hypot(y_46_re, y_46_im))
	tmp = 0.0
	if (y_46_im <= -8e+105)
		tmp = t_3;
	elseif (y_46_im <= 7e-302)
		tmp = fma(t_1, t_2, Float64(Float64(-x_46_re) / Float64(t_0 / y_46_im)));
	elseif (y_46_im <= 7.5e-147)
		tmp = Float64(t_4 * Float64(Float64(Float64(y_46_re * x_46_im) - Float64(y_46_im * x_46_re)) / hypot(y_46_re, y_46_im)));
	elseif (y_46_im <= 1.18e+176)
		tmp = Float64(Float64(t_4 * Float64(y_46_re / Float64(hypot(y_46_re, y_46_im) / x_46_im))) - Float64(y_46_im * Float64(x_46_re / t_0)));
	else
		tmp = t_3;
	end
	return tmp
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[Power[N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision], 2.0], $MachinePrecision]}, Block[{t$95$1 = N[(y$46$re / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(x$46$im / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$3 = N[(t$95$1 * t$95$2 + N[((-x$46$re) / y$46$im), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$4 = N[(1.0 / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y$46$im, -8e+105], t$95$3, If[LessEqual[y$46$im, 7e-302], N[(t$95$1 * t$95$2 + N[((-x$46$re) / N[(t$95$0 / y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[y$46$im, 7.5e-147], N[(t$95$4 * N[(N[(N[(y$46$re * x$46$im), $MachinePrecision] - N[(y$46$im * x$46$re), $MachinePrecision]), $MachinePrecision] / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[y$46$im, 1.18e+176], N[(N[(t$95$4 * N[(y$46$re / N[(N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision] / x$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(y$46$im * N[(x$46$re / t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], t$95$3]]]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := {\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}\\
t_1 := \frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}\\
t_2 := \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}\\
t_3 := \mathsf{fma}\left(t_1, t_2, \frac{-x.re}{y.im}\right)\\
t_4 := \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)}\\
\mathbf{if}\;y.im \leq -8 \cdot 10^{+105}:\\
\;\;\;\;t_3\\

\mathbf{elif}\;y.im \leq 7 \cdot 10^{-302}:\\
\;\;\;\;\mathsf{fma}\left(t_1, t_2, \frac{-x.re}{\frac{t_0}{y.im}}\right)\\

\mathbf{elif}\;y.im \leq 7.5 \cdot 10^{-147}:\\
\;\;\;\;t_4 \cdot \frac{y.re \cdot x.im - y.im \cdot x.re}{\mathsf{hypot}\left(y.re, y.im\right)}\\

\mathbf{elif}\;y.im \leq 1.18 \cdot 10^{+176}:\\
\;\;\;\;t_4 \cdot \frac{y.re}{\frac{\mathsf{hypot}\left(y.re, y.im\right)}{x.im}} - y.im \cdot \frac{x.re}{t_0}\\

\mathbf{else}:\\
\;\;\;\;t_3\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if y.im < -7.9999999999999995e105 or 1.18000000000000006e176 < y.im

    1. Initial program 36.5%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. div-sub36.5%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} - \frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}} \]
      2. sub-neg36.5%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      3. *-commutative36.5%

        \[\leadsto \frac{\color{blue}{y.re \cdot x.im}}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      4. add-sqr-sqrt36.5%

        \[\leadsto \frac{y.re \cdot x.im}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      5. times-frac36.7%

        \[\leadsto \color{blue}{\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      6. fma-def36.7%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      7. hypot-def36.7%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      8. hypot-def50.0%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      9. associate-/l*52.8%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\color{blue}{\frac{x.re}{\frac{y.re \cdot y.re + y.im \cdot y.im}{y.im}}}\right) \]
      10. add-sqr-sqrt52.8%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}}{y.im}}\right) \]
      11. pow252.8%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{{\left(\sqrt{y.re \cdot y.re + y.im \cdot y.im}\right)}^{2}}}{y.im}}\right) \]
      12. hypot-def52.8%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\color{blue}{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}}^{2}}{y.im}}\right) \]
    3. Applied egg-rr52.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}\right)} \]
    4. Taylor expanded in y.re around 0 96.2%

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

    if -7.9999999999999995e105 < y.im < 7.0000000000000003e-302

    1. Initial program 81.2%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. div-sub80.0%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} - \frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}} \]
      2. sub-neg80.0%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      3. *-commutative80.0%

        \[\leadsto \frac{\color{blue}{y.re \cdot x.im}}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      4. add-sqr-sqrt80.0%

        \[\leadsto \frac{y.re \cdot x.im}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      5. times-frac84.0%

        \[\leadsto \color{blue}{\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      6. fma-def84.0%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      7. hypot-def84.1%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      8. hypot-def96.5%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      9. associate-/l*97.6%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\color{blue}{\frac{x.re}{\frac{y.re \cdot y.re + y.im \cdot y.im}{y.im}}}\right) \]
      10. add-sqr-sqrt97.6%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}}{y.im}}\right) \]
      11. pow297.6%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{{\left(\sqrt{y.re \cdot y.re + y.im \cdot y.im}\right)}^{2}}}{y.im}}\right) \]
      12. hypot-def97.6%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\color{blue}{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}}^{2}}{y.im}}\right) \]
    3. Applied egg-rr97.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}\right)} \]

    if 7.0000000000000003e-302 < y.im < 7.50000000000000047e-147

    1. Initial program 76.5%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity76.5%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt76.5%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac76.6%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def76.7%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def94.2%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr94.2%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]

    if 7.50000000000000047e-147 < y.im < 1.18000000000000006e176

    1. Initial program 73.4%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. div-sub73.4%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} - \frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}} \]
      2. sub-neg73.4%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      3. *-un-lft-identity73.4%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re\right)}}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      4. add-sqr-sqrt73.4%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      5. times-frac73.4%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      6. fma-def73.4%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, \frac{x.im \cdot y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      7. hypot-def73.4%

        \[\leadsto \mathsf{fma}\left(\frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, \frac{x.im \cdot y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      8. hypot-def77.6%

        \[\leadsto \mathsf{fma}\left(\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im \cdot y.re}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      9. associate-/l*81.5%

        \[\leadsto \mathsf{fma}\left(\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im \cdot y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, -\color{blue}{\frac{x.re}{\frac{y.re \cdot y.re + y.im \cdot y.im}{y.im}}}\right) \]
      10. add-sqr-sqrt81.5%

        \[\leadsto \mathsf{fma}\left(\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im \cdot y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}}{y.im}}\right) \]
      11. pow281.5%

        \[\leadsto \mathsf{fma}\left(\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im \cdot y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{{\left(\sqrt{y.re \cdot y.re + y.im \cdot y.im}\right)}^{2}}}{y.im}}\right) \]
      12. hypot-def81.5%

        \[\leadsto \mathsf{fma}\left(\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im \cdot y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\color{blue}{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}}^{2}}{y.im}}\right) \]
    3. Applied egg-rr81.5%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im \cdot y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}\right)} \]
    4. Step-by-step derivation
      1. fma-neg81.5%

        \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re}{\mathsf{hypot}\left(y.re, y.im\right)} - \frac{x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}} \]
      2. *-commutative81.5%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{\color{blue}{y.re \cdot x.im}}{\mathsf{hypot}\left(y.re, y.im\right)} - \frac{x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}} \]
      3. associate-/l*94.0%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\frac{y.re}{\frac{\mathsf{hypot}\left(y.re, y.im\right)}{x.im}}} - \frac{x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}} \]
      4. associate-/r/92.5%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{y.re}{\frac{\mathsf{hypot}\left(y.re, y.im\right)}{x.im}} - \color{blue}{\frac{x.re}{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}} \cdot y.im} \]
      5. *-commutative92.5%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{y.re}{\frac{\mathsf{hypot}\left(y.re, y.im\right)}{x.im}} - \color{blue}{y.im \cdot \frac{x.re}{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}} \]
    5. Simplified92.5%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{y.re}{\frac{\mathsf{hypot}\left(y.re, y.im\right)}{x.im}} - y.im \cdot \frac{x.re}{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification95.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y.im \leq -8 \cdot 10^{+105}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{-x.re}{y.im}\right)\\ \mathbf{elif}\;y.im \leq 7 \cdot 10^{-302}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{-x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}\right)\\ \mathbf{elif}\;y.im \leq 7.5 \cdot 10^{-147}:\\ \;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{y.re \cdot x.im - y.im \cdot x.re}{\mathsf{hypot}\left(y.re, y.im\right)}\\ \mathbf{elif}\;y.im \leq 1.18 \cdot 10^{+176}:\\ \;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{y.re}{\frac{\mathsf{hypot}\left(y.re, y.im\right)}{x.im}} - y.im \cdot \frac{x.re}{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{-x.re}{y.im}\right)\\ \end{array} \]

Alternative 3: 89.5% accurate, 0.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := y.re \cdot x.im - y.im \cdot x.re\\ t_1 := \frac{t_0}{y.re \cdot y.re + y.im \cdot y.im}\\ \mathbf{if}\;t_1 \leq -1 \cdot 10^{+261} \lor \neg \left(t_1 \leq 5 \cdot 10^{+307}\right):\\ \;\;\;\;\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{-x.re}{y.im}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{t_0}{\mathsf{hypot}\left(y.re, y.im\right)}\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0 (- (* y.re x.im) (* y.im x.re)))
        (t_1 (/ t_0 (+ (* y.re y.re) (* y.im y.im)))))
   (if (or (<= t_1 -1e+261) (not (<= t_1 5e+307)))
     (fma
      (/ y.re (hypot y.re y.im))
      (/ x.im (hypot y.re y.im))
      (/ (- x.re) y.im))
     (* (/ 1.0 (hypot y.re y.im)) (/ t_0 (hypot y.re y.im))))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = (y_46_re * x_46_im) - (y_46_im * x_46_re);
	double t_1 = t_0 / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	double tmp;
	if ((t_1 <= -1e+261) || !(t_1 <= 5e+307)) {
		tmp = fma((y_46_re / hypot(y_46_re, y_46_im)), (x_46_im / hypot(y_46_re, y_46_im)), (-x_46_re / y_46_im));
	} else {
		tmp = (1.0 / hypot(y_46_re, y_46_im)) * (t_0 / hypot(y_46_re, y_46_im));
	}
	return tmp;
}
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = Float64(Float64(y_46_re * x_46_im) - Float64(y_46_im * x_46_re))
	t_1 = Float64(t_0 / Float64(Float64(y_46_re * y_46_re) + Float64(y_46_im * y_46_im)))
	tmp = 0.0
	if ((t_1 <= -1e+261) || !(t_1 <= 5e+307))
		tmp = fma(Float64(y_46_re / hypot(y_46_re, y_46_im)), Float64(x_46_im / hypot(y_46_re, y_46_im)), Float64(Float64(-x_46_re) / y_46_im));
	else
		tmp = Float64(Float64(1.0 / hypot(y_46_re, y_46_im)) * Float64(t_0 / hypot(y_46_re, y_46_im)));
	end
	return tmp
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[(N[(y$46$re * x$46$im), $MachinePrecision] - N[(y$46$im * x$46$re), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(t$95$0 / N[(N[(y$46$re * y$46$re), $MachinePrecision] + N[(y$46$im * y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$1, -1e+261], N[Not[LessEqual[t$95$1, 5e+307]], $MachinePrecision]], N[(N[(y$46$re / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision] * N[(x$46$im / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision] + N[((-x$46$re) / y$46$im), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision] * N[(t$95$0 / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := y.re \cdot x.im - y.im \cdot x.re\\
t_1 := \frac{t_0}{y.re \cdot y.re + y.im \cdot y.im}\\
\mathbf{if}\;t_1 \leq -1 \cdot 10^{+261} \lor \neg \left(t_1 \leq 5 \cdot 10^{+307}\right):\\
\;\;\;\;\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{-x.re}{y.im}\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{t_0}{\mathsf{hypot}\left(y.re, y.im\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (-.f64 (*.f64 x.im y.re) (*.f64 x.re y.im)) (+.f64 (*.f64 y.re y.re) (*.f64 y.im y.im))) < -9.9999999999999993e260 or 5e307 < (/.f64 (-.f64 (*.f64 x.im y.re) (*.f64 x.re y.im)) (+.f64 (*.f64 y.re y.re) (*.f64 y.im y.im)))

    1. Initial program 21.6%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. div-sub16.2%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} - \frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}} \]
      2. sub-neg16.2%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      3. *-commutative16.2%

        \[\leadsto \frac{\color{blue}{y.re \cdot x.im}}{y.re \cdot y.re + y.im \cdot y.im} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      4. add-sqr-sqrt16.2%

        \[\leadsto \frac{y.re \cdot x.im}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      5. times-frac24.7%

        \[\leadsto \color{blue}{\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} + \left(-\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      6. fma-def24.7%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right)} \]
      7. hypot-def24.7%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, \frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      8. hypot-def53.3%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}}, -\frac{x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\right) \]
      9. associate-/l*61.7%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\color{blue}{\frac{x.re}{\frac{y.re \cdot y.re + y.im \cdot y.im}{y.im}}}\right) \]
      10. add-sqr-sqrt61.7%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}}{y.im}}\right) \]
      11. pow261.7%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{\color{blue}{{\left(\sqrt{y.re \cdot y.re + y.im \cdot y.im}\right)}^{2}}}{y.im}}\right) \]
      12. hypot-def61.7%

        \[\leadsto \mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\color{blue}{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}}^{2}}{y.im}}\right) \]
    3. Applied egg-rr61.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, -\frac{x.re}{\frac{{\left(\mathsf{hypot}\left(y.re, y.im\right)\right)}^{2}}{y.im}}\right)} \]
    4. Taylor expanded in y.re around 0 75.4%

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

    if -9.9999999999999993e260 < (/.f64 (-.f64 (*.f64 x.im y.re) (*.f64 x.re y.im)) (+.f64 (*.f64 y.re y.re) (*.f64 y.im y.im))) < 5e307

    1. Initial program 87.1%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity87.1%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt87.1%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac87.0%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def87.0%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def99.0%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr99.0%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification91.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im} \leq -1 \cdot 10^{+261} \lor \neg \left(\frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im} \leq 5 \cdot 10^{+307}\right):\\ \;\;\;\;\mathsf{fma}\left(\frac{y.re}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{x.im}{\mathsf{hypot}\left(y.re, y.im\right)}, \frac{-x.re}{y.im}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{y.re \cdot x.im - y.im \cdot x.re}{\mathsf{hypot}\left(y.re, y.im\right)}\\ \end{array} \]

Alternative 4: 84.9% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := y.re \cdot x.im - y.im \cdot x.re\\ \mathbf{if}\;\frac{t_0}{y.re \cdot y.re + y.im \cdot y.im} \leq 5 \cdot 10^{+307}:\\ \;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{t_0}{\mathsf{hypot}\left(y.re, y.im\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{x.im}{y.im \cdot \frac{y.im}{y.re}} - \frac{x.re}{y.im}\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0 (- (* y.re x.im) (* y.im x.re))))
   (if (<= (/ t_0 (+ (* y.re y.re) (* y.im y.im))) 5e+307)
     (* (/ 1.0 (hypot y.re y.im)) (/ t_0 (hypot y.re y.im)))
     (- (/ x.im (* y.im (/ y.im y.re))) (/ x.re y.im)))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = (y_46_re * x_46_im) - (y_46_im * x_46_re);
	double tmp;
	if ((t_0 / ((y_46_re * y_46_re) + (y_46_im * y_46_im))) <= 5e+307) {
		tmp = (1.0 / hypot(y_46_re, y_46_im)) * (t_0 / hypot(y_46_re, y_46_im));
	} else {
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	}
	return tmp;
}
public static double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = (y_46_re * x_46_im) - (y_46_im * x_46_re);
	double tmp;
	if ((t_0 / ((y_46_re * y_46_re) + (y_46_im * y_46_im))) <= 5e+307) {
		tmp = (1.0 / Math.hypot(y_46_re, y_46_im)) * (t_0 / Math.hypot(y_46_re, y_46_im));
	} else {
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	}
	return tmp;
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	t_0 = (y_46_re * x_46_im) - (y_46_im * x_46_re)
	tmp = 0
	if (t_0 / ((y_46_re * y_46_re) + (y_46_im * y_46_im))) <= 5e+307:
		tmp = (1.0 / math.hypot(y_46_re, y_46_im)) * (t_0 / math.hypot(y_46_re, y_46_im))
	else:
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im)
	return tmp
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = Float64(Float64(y_46_re * x_46_im) - Float64(y_46_im * x_46_re))
	tmp = 0.0
	if (Float64(t_0 / Float64(Float64(y_46_re * y_46_re) + Float64(y_46_im * y_46_im))) <= 5e+307)
		tmp = Float64(Float64(1.0 / hypot(y_46_re, y_46_im)) * Float64(t_0 / hypot(y_46_re, y_46_im)));
	else
		tmp = Float64(Float64(x_46_im / Float64(y_46_im * Float64(y_46_im / y_46_re))) - Float64(x_46_re / y_46_im));
	end
	return tmp
end
function tmp_2 = code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = (y_46_re * x_46_im) - (y_46_im * x_46_re);
	tmp = 0.0;
	if ((t_0 / ((y_46_re * y_46_re) + (y_46_im * y_46_im))) <= 5e+307)
		tmp = (1.0 / hypot(y_46_re, y_46_im)) * (t_0 / hypot(y_46_re, y_46_im));
	else
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	end
	tmp_2 = tmp;
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[(N[(y$46$re * x$46$im), $MachinePrecision] - N[(y$46$im * x$46$re), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(t$95$0 / N[(N[(y$46$re * y$46$re), $MachinePrecision] + N[(y$46$im * y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 5e+307], N[(N[(1.0 / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision] * N[(t$95$0 / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(x$46$im / N[(y$46$im * N[(y$46$im / y$46$re), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(x$46$re / y$46$im), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := y.re \cdot x.im - y.im \cdot x.re\\
\mathbf{if}\;\frac{t_0}{y.re \cdot y.re + y.im \cdot y.im} \leq 5 \cdot 10^{+307}:\\
\;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{t_0}{\mathsf{hypot}\left(y.re, y.im\right)}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (-.f64 (*.f64 x.im y.re) (*.f64 x.re y.im)) (+.f64 (*.f64 y.re y.re) (*.f64 y.im y.im))) < 5e307

    1. Initial program 85.1%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity85.1%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt85.0%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac85.0%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def85.0%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def96.1%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr96.1%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]

    if 5e307 < (/.f64 (-.f64 (*.f64 x.im y.re) (*.f64 x.re y.im)) (+.f64 (*.f64 y.re y.re) (*.f64 y.im y.im)))

    1. Initial program 13.3%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in y.re around 0 49.7%

      \[\leadsto \color{blue}{-1 \cdot \frac{x.re}{y.im} + \frac{x.im \cdot y.re}{{y.im}^{2}}} \]
    3. Step-by-step derivation
      1. +-commutative49.7%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{{y.im}^{2}} + -1 \cdot \frac{x.re}{y.im}} \]
      2. mul-1-neg49.7%

        \[\leadsto \frac{x.im \cdot y.re}{{y.im}^{2}} + \color{blue}{\left(-\frac{x.re}{y.im}\right)} \]
      3. unsub-neg49.7%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{{y.im}^{2}} - \frac{x.re}{y.im}} \]
      4. associate-/l*51.8%

        \[\leadsto \color{blue}{\frac{x.im}{\frac{{y.im}^{2}}{y.re}}} - \frac{x.re}{y.im} \]
    4. Simplified51.8%

      \[\leadsto \color{blue}{\frac{x.im}{\frac{{y.im}^{2}}{y.re}} - \frac{x.re}{y.im}} \]
    5. Step-by-step derivation
      1. pow251.8%

        \[\leadsto \frac{x.im}{\frac{\color{blue}{y.im \cdot y.im}}{y.re}} - \frac{x.re}{y.im} \]
      2. *-un-lft-identity51.8%

        \[\leadsto \frac{x.im}{\frac{y.im \cdot y.im}{\color{blue}{1 \cdot y.re}}} - \frac{x.re}{y.im} \]
      3. times-frac58.0%

        \[\leadsto \frac{x.im}{\color{blue}{\frac{y.im}{1} \cdot \frac{y.im}{y.re}}} - \frac{x.re}{y.im} \]
    6. Applied egg-rr58.0%

      \[\leadsto \frac{x.im}{\color{blue}{\frac{y.im}{1} \cdot \frac{y.im}{y.re}}} - \frac{x.re}{y.im} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification86.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im} \leq 5 \cdot 10^{+307}:\\ \;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{y.re \cdot x.im - y.im \cdot x.re}{\mathsf{hypot}\left(y.re, y.im\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{x.im}{y.im \cdot \frac{y.im}{y.re}} - \frac{x.re}{y.im}\\ \end{array} \]

Alternative 5: 82.0% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im}\\ t_1 := x.im - \frac{x.re}{\frac{y.re}{y.im}}\\ \mathbf{if}\;y.re \leq -5.8 \cdot 10^{+83}:\\ \;\;\;\;\frac{1}{y.re} \cdot t_1\\ \mathbf{elif}\;y.re \leq -1.95 \cdot 10^{-120}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y.re \leq 2.15 \cdot 10^{-130}:\\ \;\;\;\;\frac{x.im}{y.im \cdot \frac{y.im}{y.re}} - \frac{x.re}{y.im}\\ \mathbf{elif}\;y.re \leq 3.1 \cdot 10^{+70}:\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot t_1\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0
         (/ (- (* y.re x.im) (* y.im x.re)) (+ (* y.re y.re) (* y.im y.im))))
        (t_1 (- x.im (/ x.re (/ y.re y.im)))))
   (if (<= y.re -5.8e+83)
     (* (/ 1.0 y.re) t_1)
     (if (<= y.re -1.95e-120)
       t_0
       (if (<= y.re 2.15e-130)
         (- (/ x.im (* y.im (/ y.im y.re))) (/ x.re y.im))
         (if (<= y.re 3.1e+70) t_0 (* (/ 1.0 (hypot y.re y.im)) 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_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	double t_1 = x_46_im - (x_46_re / (y_46_re / y_46_im));
	double tmp;
	if (y_46_re <= -5.8e+83) {
		tmp = (1.0 / y_46_re) * t_1;
	} else if (y_46_re <= -1.95e-120) {
		tmp = t_0;
	} else if (y_46_re <= 2.15e-130) {
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	} else if (y_46_re <= 3.1e+70) {
		tmp = t_0;
	} else {
		tmp = (1.0 / hypot(y_46_re, y_46_im)) * t_1;
	}
	return tmp;
}
public static double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = ((y_46_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	double t_1 = x_46_im - (x_46_re / (y_46_re / y_46_im));
	double tmp;
	if (y_46_re <= -5.8e+83) {
		tmp = (1.0 / y_46_re) * t_1;
	} else if (y_46_re <= -1.95e-120) {
		tmp = t_0;
	} else if (y_46_re <= 2.15e-130) {
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	} else if (y_46_re <= 3.1e+70) {
		tmp = t_0;
	} else {
		tmp = (1.0 / Math.hypot(y_46_re, y_46_im)) * t_1;
	}
	return tmp;
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	t_0 = ((y_46_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im))
	t_1 = x_46_im - (x_46_re / (y_46_re / y_46_im))
	tmp = 0
	if y_46_re <= -5.8e+83:
		tmp = (1.0 / y_46_re) * t_1
	elif y_46_re <= -1.95e-120:
		tmp = t_0
	elif y_46_re <= 2.15e-130:
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im)
	elif y_46_re <= 3.1e+70:
		tmp = t_0
	else:
		tmp = (1.0 / math.hypot(y_46_re, y_46_im)) * 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_re * x_46_im) - Float64(y_46_im * x_46_re)) / Float64(Float64(y_46_re * y_46_re) + Float64(y_46_im * y_46_im)))
	t_1 = Float64(x_46_im - Float64(x_46_re / Float64(y_46_re / y_46_im)))
	tmp = 0.0
	if (y_46_re <= -5.8e+83)
		tmp = Float64(Float64(1.0 / y_46_re) * t_1);
	elseif (y_46_re <= -1.95e-120)
		tmp = t_0;
	elseif (y_46_re <= 2.15e-130)
		tmp = Float64(Float64(x_46_im / Float64(y_46_im * Float64(y_46_im / y_46_re))) - Float64(x_46_re / y_46_im));
	elseif (y_46_re <= 3.1e+70)
		tmp = t_0;
	else
		tmp = Float64(Float64(1.0 / hypot(y_46_re, y_46_im)) * t_1);
	end
	return tmp
end
function tmp_2 = code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = ((y_46_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	t_1 = x_46_im - (x_46_re / (y_46_re / y_46_im));
	tmp = 0.0;
	if (y_46_re <= -5.8e+83)
		tmp = (1.0 / y_46_re) * t_1;
	elseif (y_46_re <= -1.95e-120)
		tmp = t_0;
	elseif (y_46_re <= 2.15e-130)
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	elseif (y_46_re <= 3.1e+70)
		tmp = t_0;
	else
		tmp = (1.0 / hypot(y_46_re, y_46_im)) * t_1;
	end
	tmp_2 = tmp;
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[(N[(N[(y$46$re * x$46$im), $MachinePrecision] - N[(y$46$im * x$46$re), $MachinePrecision]), $MachinePrecision] / N[(N[(y$46$re * y$46$re), $MachinePrecision] + N[(y$46$im * y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(x$46$im - N[(x$46$re / N[(y$46$re / y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y$46$re, -5.8e+83], N[(N[(1.0 / y$46$re), $MachinePrecision] * t$95$1), $MachinePrecision], If[LessEqual[y$46$re, -1.95e-120], t$95$0, If[LessEqual[y$46$re, 2.15e-130], N[(N[(x$46$im / N[(y$46$im * N[(y$46$im / y$46$re), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(x$46$re / y$46$im), $MachinePrecision]), $MachinePrecision], If[LessEqual[y$46$re, 3.1e+70], t$95$0, N[(N[(1.0 / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision] * t$95$1), $MachinePrecision]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im}\\
t_1 := x.im - \frac{x.re}{\frac{y.re}{y.im}}\\
\mathbf{if}\;y.re \leq -5.8 \cdot 10^{+83}:\\
\;\;\;\;\frac{1}{y.re} \cdot t_1\\

\mathbf{elif}\;y.re \leq -1.95 \cdot 10^{-120}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;y.re \leq 2.15 \cdot 10^{-130}:\\
\;\;\;\;\frac{x.im}{y.im \cdot \frac{y.im}{y.re}} - \frac{x.re}{y.im}\\

\mathbf{elif}\;y.re \leq 3.1 \cdot 10^{+70}:\\
\;\;\;\;t_0\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot t_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if y.re < -5.79999999999999999e83

    1. Initial program 40.2%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity40.2%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt40.2%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac40.2%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def40.2%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def54.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr54.9%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    4. Taylor expanded in y.re around inf 30.9%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im + -1 \cdot \frac{x.re \cdot y.im}{y.re}\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg30.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im + \color{blue}{\left(-\frac{x.re \cdot y.im}{y.re}\right)}\right) \]
      2. unsub-neg30.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re \cdot y.im}{y.re}\right)} \]
      3. associate-/l*31.0%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im - \color{blue}{\frac{x.re}{\frac{y.re}{y.im}}}\right) \]
    6. Simplified31.0%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)} \]
    7. Taylor expanded in y.re around inf 90.7%

      \[\leadsto \color{blue}{\frac{1}{y.re}} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right) \]

    if -5.79999999999999999e83 < y.re < -1.9500000000000001e-120 or 2.15000000000000014e-130 < y.re < 3.1000000000000003e70

    1. Initial program 83.7%

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

    if -1.9500000000000001e-120 < y.re < 2.15000000000000014e-130

    1. Initial program 72.0%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in y.re around 0 87.4%

      \[\leadsto \color{blue}{-1 \cdot \frac{x.re}{y.im} + \frac{x.im \cdot y.re}{{y.im}^{2}}} \]
    3. Step-by-step derivation
      1. +-commutative87.4%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{{y.im}^{2}} + -1 \cdot \frac{x.re}{y.im}} \]
      2. mul-1-neg87.4%

        \[\leadsto \frac{x.im \cdot y.re}{{y.im}^{2}} + \color{blue}{\left(-\frac{x.re}{y.im}\right)} \]
      3. unsub-neg87.4%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{{y.im}^{2}} - \frac{x.re}{y.im}} \]
      4. associate-/l*87.6%

        \[\leadsto \color{blue}{\frac{x.im}{\frac{{y.im}^{2}}{y.re}}} - \frac{x.re}{y.im} \]
    4. Simplified87.6%

      \[\leadsto \color{blue}{\frac{x.im}{\frac{{y.im}^{2}}{y.re}} - \frac{x.re}{y.im}} \]
    5. Step-by-step derivation
      1. pow287.6%

        \[\leadsto \frac{x.im}{\frac{\color{blue}{y.im \cdot y.im}}{y.re}} - \frac{x.re}{y.im} \]
      2. *-un-lft-identity87.6%

        \[\leadsto \frac{x.im}{\frac{y.im \cdot y.im}{\color{blue}{1 \cdot y.re}}} - \frac{x.re}{y.im} \]
      3. times-frac92.4%

        \[\leadsto \frac{x.im}{\color{blue}{\frac{y.im}{1} \cdot \frac{y.im}{y.re}}} - \frac{x.re}{y.im} \]
    6. Applied egg-rr92.4%

      \[\leadsto \frac{x.im}{\color{blue}{\frac{y.im}{1} \cdot \frac{y.im}{y.re}}} - \frac{x.re}{y.im} \]

    if 3.1000000000000003e70 < y.re

    1. Initial program 38.8%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity38.8%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt38.8%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac38.8%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def38.8%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def55.6%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr55.6%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    4. Taylor expanded in y.re around inf 73.1%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im + -1 \cdot \frac{x.re \cdot y.im}{y.re}\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg73.1%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im + \color{blue}{\left(-\frac{x.re \cdot y.im}{y.re}\right)}\right) \]
      2. unsub-neg73.1%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re \cdot y.im}{y.re}\right)} \]
      3. associate-/l*78.6%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im - \color{blue}{\frac{x.re}{\frac{y.re}{y.im}}}\right) \]
    6. Simplified78.6%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification86.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y.re \leq -5.8 \cdot 10^{+83}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \mathbf{elif}\;y.re \leq -1.95 \cdot 10^{-120}:\\ \;\;\;\;\frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im}\\ \mathbf{elif}\;y.re \leq 2.15 \cdot 10^{-130}:\\ \;\;\;\;\frac{x.im}{y.im \cdot \frac{y.im}{y.re}} - \frac{x.re}{y.im}\\ \mathbf{elif}\;y.re \leq 3.1 \cdot 10^{+70}:\\ \;\;\;\;\frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \end{array} \]

Alternative 6: 81.1% accurate, 0.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)}\\ t_1 := \frac{x.im}{\frac{y.im}{y.re}}\\ \mathbf{if}\;y.im \leq -1.55 \cdot 10^{+78}:\\ \;\;\;\;t_0 \cdot \left(x.re - t_1\right)\\ \mathbf{elif}\;y.im \leq -1.75 \cdot 10^{-129}:\\ \;\;\;\;\frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im}\\ \mathbf{elif}\;y.im \leq 1.1 \cdot 10^{-34}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \mathbf{else}:\\ \;\;\;\;t_0 \cdot \left(t_1 - x.re\right)\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0 (/ 1.0 (hypot y.re y.im))) (t_1 (/ x.im (/ y.im y.re))))
   (if (<= y.im -1.55e+78)
     (* t_0 (- x.re t_1))
     (if (<= y.im -1.75e-129)
       (/ (- (* y.re x.im) (* y.im x.re)) (+ (* y.re y.re) (* y.im y.im)))
       (if (<= y.im 1.1e-34)
         (* (/ 1.0 y.re) (- x.im (/ x.re (/ y.re y.im))))
         (* t_0 (- t_1 x.re)))))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = 1.0 / hypot(y_46_re, y_46_im);
	double t_1 = x_46_im / (y_46_im / y_46_re);
	double tmp;
	if (y_46_im <= -1.55e+78) {
		tmp = t_0 * (x_46_re - t_1);
	} else if (y_46_im <= -1.75e-129) {
		tmp = ((y_46_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	} else if (y_46_im <= 1.1e-34) {
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	} else {
		tmp = t_0 * (t_1 - x_46_re);
	}
	return tmp;
}
public static double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = 1.0 / Math.hypot(y_46_re, y_46_im);
	double t_1 = x_46_im / (y_46_im / y_46_re);
	double tmp;
	if (y_46_im <= -1.55e+78) {
		tmp = t_0 * (x_46_re - t_1);
	} else if (y_46_im <= -1.75e-129) {
		tmp = ((y_46_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	} else if (y_46_im <= 1.1e-34) {
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	} else {
		tmp = t_0 * (t_1 - x_46_re);
	}
	return tmp;
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	t_0 = 1.0 / math.hypot(y_46_re, y_46_im)
	t_1 = x_46_im / (y_46_im / y_46_re)
	tmp = 0
	if y_46_im <= -1.55e+78:
		tmp = t_0 * (x_46_re - t_1)
	elif y_46_im <= -1.75e-129:
		tmp = ((y_46_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im))
	elif y_46_im <= 1.1e-34:
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)))
	else:
		tmp = t_0 * (t_1 - x_46_re)
	return tmp
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = Float64(1.0 / hypot(y_46_re, y_46_im))
	t_1 = Float64(x_46_im / Float64(y_46_im / y_46_re))
	tmp = 0.0
	if (y_46_im <= -1.55e+78)
		tmp = Float64(t_0 * Float64(x_46_re - t_1));
	elseif (y_46_im <= -1.75e-129)
		tmp = Float64(Float64(Float64(y_46_re * x_46_im) - Float64(y_46_im * x_46_re)) / Float64(Float64(y_46_re * y_46_re) + Float64(y_46_im * y_46_im)));
	elseif (y_46_im <= 1.1e-34)
		tmp = Float64(Float64(1.0 / y_46_re) * Float64(x_46_im - Float64(x_46_re / Float64(y_46_re / y_46_im))));
	else
		tmp = Float64(t_0 * Float64(t_1 - x_46_re));
	end
	return tmp
end
function tmp_2 = code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = 1.0 / hypot(y_46_re, y_46_im);
	t_1 = x_46_im / (y_46_im / y_46_re);
	tmp = 0.0;
	if (y_46_im <= -1.55e+78)
		tmp = t_0 * (x_46_re - t_1);
	elseif (y_46_im <= -1.75e-129)
		tmp = ((y_46_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	elseif (y_46_im <= 1.1e-34)
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	else
		tmp = t_0 * (t_1 - x_46_re);
	end
	tmp_2 = tmp;
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[(1.0 / N[Sqrt[y$46$re ^ 2 + y$46$im ^ 2], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(x$46$im / N[(y$46$im / y$46$re), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y$46$im, -1.55e+78], N[(t$95$0 * N[(x$46$re - t$95$1), $MachinePrecision]), $MachinePrecision], If[LessEqual[y$46$im, -1.75e-129], N[(N[(N[(y$46$re * x$46$im), $MachinePrecision] - N[(y$46$im * x$46$re), $MachinePrecision]), $MachinePrecision] / N[(N[(y$46$re * y$46$re), $MachinePrecision] + N[(y$46$im * y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[y$46$im, 1.1e-34], N[(N[(1.0 / y$46$re), $MachinePrecision] * N[(x$46$im - N[(x$46$re / N[(y$46$re / y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(t$95$0 * N[(t$95$1 - x$46$re), $MachinePrecision]), $MachinePrecision]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)}\\
t_1 := \frac{x.im}{\frac{y.im}{y.re}}\\
\mathbf{if}\;y.im \leq -1.55 \cdot 10^{+78}:\\
\;\;\;\;t_0 \cdot \left(x.re - t_1\right)\\

\mathbf{elif}\;y.im \leq -1.75 \cdot 10^{-129}:\\
\;\;\;\;\frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im}\\

\mathbf{elif}\;y.im \leq 1.1 \cdot 10^{-34}:\\
\;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\

\mathbf{else}:\\
\;\;\;\;t_0 \cdot \left(t_1 - x.re\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if y.im < -1.55e78

    1. Initial program 43.3%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity43.3%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt43.3%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac43.4%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def43.4%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def54.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr54.9%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    4. Taylor expanded in y.im around -inf 83.2%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.re + -1 \cdot \frac{x.im \cdot y.re}{y.im}\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg83.2%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.re + \color{blue}{\left(-\frac{x.im \cdot y.re}{y.im}\right)}\right) \]
      2. unsub-neg83.2%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.re - \frac{x.im \cdot y.re}{y.im}\right)} \]
      3. associate-/l*90.7%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.re - \color{blue}{\frac{x.im}{\frac{y.im}{y.re}}}\right) \]
    6. Simplified90.7%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.re - \frac{x.im}{\frac{y.im}{y.re}}\right)} \]

    if -1.55e78 < y.im < -1.7499999999999999e-129

    1. Initial program 90.0%

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

    if -1.7499999999999999e-129 < y.im < 1.0999999999999999e-34

    1. Initial program 73.6%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity73.6%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt73.6%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac73.5%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def73.5%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def82.3%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr82.3%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    4. Taylor expanded in y.re around inf 46.0%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im + -1 \cdot \frac{x.re \cdot y.im}{y.re}\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg46.0%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im + \color{blue}{\left(-\frac{x.re \cdot y.im}{y.re}\right)}\right) \]
      2. unsub-neg46.0%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re \cdot y.im}{y.re}\right)} \]
      3. associate-/l*46.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im - \color{blue}{\frac{x.re}{\frac{y.re}{y.im}}}\right) \]
    6. Simplified46.9%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)} \]
    7. Taylor expanded in y.re around inf 89.8%

      \[\leadsto \color{blue}{\frac{1}{y.re}} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right) \]

    if 1.0999999999999999e-34 < y.im

    1. Initial program 57.3%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity57.3%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt57.3%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac57.4%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def57.4%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def74.6%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr74.6%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    4. Taylor expanded in y.re around 0 79.1%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(-1 \cdot x.re + \frac{x.im \cdot y.re}{y.im}\right)} \]
    5. Step-by-step derivation
      1. +-commutative79.1%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(\frac{x.im \cdot y.re}{y.im} + -1 \cdot x.re\right)} \]
      2. mul-1-neg79.1%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(\frac{x.im \cdot y.re}{y.im} + \color{blue}{\left(-x.re\right)}\right) \]
      3. unsub-neg79.1%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(\frac{x.im \cdot y.re}{y.im} - x.re\right)} \]
      4. associate-/l*79.2%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(\color{blue}{\frac{x.im}{\frac{y.im}{y.re}}} - x.re\right) \]
    6. Simplified79.2%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(\frac{x.im}{\frac{y.im}{y.re}} - x.re\right)} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification87.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y.im \leq -1.55 \cdot 10^{+78}:\\ \;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.re - \frac{x.im}{\frac{y.im}{y.re}}\right)\\ \mathbf{elif}\;y.im \leq -1.75 \cdot 10^{-129}:\\ \;\;\;\;\frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im}\\ \mathbf{elif}\;y.im \leq 1.1 \cdot 10^{-34}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(\frac{x.im}{\frac{y.im}{y.re}} - x.re\right)\\ \end{array} \]

Alternative 7: 81.9% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im}\\ t_1 := \frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \mathbf{if}\;y.re \leq -2.05 \cdot 10^{+83}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;y.re \leq -1.5 \cdot 10^{-120}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y.re \leq 4 \cdot 10^{-130}:\\ \;\;\;\;\frac{x.im}{y.im \cdot \frac{y.im}{y.re}} - \frac{x.re}{y.im}\\ \mathbf{elif}\;y.re \leq 2 \cdot 10^{+70}:\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;t_1\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0
         (/ (- (* y.re x.im) (* y.im x.re)) (+ (* y.re y.re) (* y.im y.im))))
        (t_1 (* (/ 1.0 y.re) (- x.im (/ x.re (/ y.re y.im))))))
   (if (<= y.re -2.05e+83)
     t_1
     (if (<= y.re -1.5e-120)
       t_0
       (if (<= y.re 4e-130)
         (- (/ x.im (* y.im (/ y.im y.re))) (/ x.re y.im))
         (if (<= y.re 2e+70) 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_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	double t_1 = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	double tmp;
	if (y_46_re <= -2.05e+83) {
		tmp = t_1;
	} else if (y_46_re <= -1.5e-120) {
		tmp = t_0;
	} else if (y_46_re <= 4e-130) {
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	} else if (y_46_re <= 2e+70) {
		tmp = t_0;
	} else {
		tmp = t_1;
	}
	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) :: t_0
    real(8) :: t_1
    real(8) :: tmp
    t_0 = ((y_46re * x_46im) - (y_46im * x_46re)) / ((y_46re * y_46re) + (y_46im * y_46im))
    t_1 = (1.0d0 / y_46re) * (x_46im - (x_46re / (y_46re / y_46im)))
    if (y_46re <= (-2.05d+83)) then
        tmp = t_1
    else if (y_46re <= (-1.5d-120)) then
        tmp = t_0
    else if (y_46re <= 4d-130) then
        tmp = (x_46im / (y_46im * (y_46im / y_46re))) - (x_46re / y_46im)
    else if (y_46re <= 2d+70) then
        tmp = t_0
    else
        tmp = t_1
    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 t_0 = ((y_46_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	double t_1 = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	double tmp;
	if (y_46_re <= -2.05e+83) {
		tmp = t_1;
	} else if (y_46_re <= -1.5e-120) {
		tmp = t_0;
	} else if (y_46_re <= 4e-130) {
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	} else if (y_46_re <= 2e+70) {
		tmp = t_0;
	} else {
		tmp = t_1;
	}
	return tmp;
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	t_0 = ((y_46_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im))
	t_1 = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)))
	tmp = 0
	if y_46_re <= -2.05e+83:
		tmp = t_1
	elif y_46_re <= -1.5e-120:
		tmp = t_0
	elif y_46_re <= 4e-130:
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im)
	elif y_46_re <= 2e+70:
		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_re * x_46_im) - Float64(y_46_im * x_46_re)) / Float64(Float64(y_46_re * y_46_re) + Float64(y_46_im * y_46_im)))
	t_1 = Float64(Float64(1.0 / y_46_re) * Float64(x_46_im - Float64(x_46_re / Float64(y_46_re / y_46_im))))
	tmp = 0.0
	if (y_46_re <= -2.05e+83)
		tmp = t_1;
	elseif (y_46_re <= -1.5e-120)
		tmp = t_0;
	elseif (y_46_re <= 4e-130)
		tmp = Float64(Float64(x_46_im / Float64(y_46_im * Float64(y_46_im / y_46_re))) - Float64(x_46_re / y_46_im));
	elseif (y_46_re <= 2e+70)
		tmp = t_0;
	else
		tmp = t_1;
	end
	return tmp
end
function tmp_2 = code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = ((y_46_re * x_46_im) - (y_46_im * x_46_re)) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	t_1 = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	tmp = 0.0;
	if (y_46_re <= -2.05e+83)
		tmp = t_1;
	elseif (y_46_re <= -1.5e-120)
		tmp = t_0;
	elseif (y_46_re <= 4e-130)
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	elseif (y_46_re <= 2e+70)
		tmp = t_0;
	else
		tmp = t_1;
	end
	tmp_2 = tmp;
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[(N[(N[(y$46$re * x$46$im), $MachinePrecision] - N[(y$46$im * x$46$re), $MachinePrecision]), $MachinePrecision] / N[(N[(y$46$re * y$46$re), $MachinePrecision] + N[(y$46$im * y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(1.0 / y$46$re), $MachinePrecision] * N[(x$46$im - N[(x$46$re / N[(y$46$re / y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y$46$re, -2.05e+83], t$95$1, If[LessEqual[y$46$re, -1.5e-120], t$95$0, If[LessEqual[y$46$re, 4e-130], N[(N[(x$46$im / N[(y$46$im * N[(y$46$im / y$46$re), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(x$46$re / y$46$im), $MachinePrecision]), $MachinePrecision], If[LessEqual[y$46$re, 2e+70], t$95$0, t$95$1]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im}\\
t_1 := \frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\
\mathbf{if}\;y.re \leq -2.05 \cdot 10^{+83}:\\
\;\;\;\;t_1\\

\mathbf{elif}\;y.re \leq -1.5 \cdot 10^{-120}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;y.re \leq 4 \cdot 10^{-130}:\\
\;\;\;\;\frac{x.im}{y.im \cdot \frac{y.im}{y.re}} - \frac{x.re}{y.im}\\

\mathbf{elif}\;y.re \leq 2 \cdot 10^{+70}:\\
\;\;\;\;t_0\\

\mathbf{else}:\\
\;\;\;\;t_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y.re < -2.05e83 or 2.00000000000000015e70 < y.re

    1. Initial program 39.6%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity39.6%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt39.6%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac39.5%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def39.5%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def55.2%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr55.2%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    4. Taylor expanded in y.re around inf 50.3%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im + -1 \cdot \frac{x.re \cdot y.im}{y.re}\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg50.3%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im + \color{blue}{\left(-\frac{x.re \cdot y.im}{y.re}\right)}\right) \]
      2. unsub-neg50.3%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re \cdot y.im}{y.re}\right)} \]
      3. associate-/l*52.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im - \color{blue}{\frac{x.re}{\frac{y.re}{y.im}}}\right) \]
    6. Simplified52.9%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)} \]
    7. Taylor expanded in y.re around inf 84.9%

      \[\leadsto \color{blue}{\frac{1}{y.re}} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right) \]

    if -2.05e83 < y.re < -1.50000000000000005e-120 or 4.0000000000000003e-130 < y.re < 2.00000000000000015e70

    1. Initial program 83.7%

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

    if -1.50000000000000005e-120 < y.re < 4.0000000000000003e-130

    1. Initial program 72.0%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in y.re around 0 87.4%

      \[\leadsto \color{blue}{-1 \cdot \frac{x.re}{y.im} + \frac{x.im \cdot y.re}{{y.im}^{2}}} \]
    3. Step-by-step derivation
      1. +-commutative87.4%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{{y.im}^{2}} + -1 \cdot \frac{x.re}{y.im}} \]
      2. mul-1-neg87.4%

        \[\leadsto \frac{x.im \cdot y.re}{{y.im}^{2}} + \color{blue}{\left(-\frac{x.re}{y.im}\right)} \]
      3. unsub-neg87.4%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{{y.im}^{2}} - \frac{x.re}{y.im}} \]
      4. associate-/l*87.6%

        \[\leadsto \color{blue}{\frac{x.im}{\frac{{y.im}^{2}}{y.re}}} - \frac{x.re}{y.im} \]
    4. Simplified87.6%

      \[\leadsto \color{blue}{\frac{x.im}{\frac{{y.im}^{2}}{y.re}} - \frac{x.re}{y.im}} \]
    5. Step-by-step derivation
      1. pow287.6%

        \[\leadsto \frac{x.im}{\frac{\color{blue}{y.im \cdot y.im}}{y.re}} - \frac{x.re}{y.im} \]
      2. *-un-lft-identity87.6%

        \[\leadsto \frac{x.im}{\frac{y.im \cdot y.im}{\color{blue}{1 \cdot y.re}}} - \frac{x.re}{y.im} \]
      3. times-frac92.4%

        \[\leadsto \frac{x.im}{\color{blue}{\frac{y.im}{1} \cdot \frac{y.im}{y.re}}} - \frac{x.re}{y.im} \]
    6. Applied egg-rr92.4%

      \[\leadsto \frac{x.im}{\color{blue}{\frac{y.im}{1} \cdot \frac{y.im}{y.re}}} - \frac{x.re}{y.im} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification86.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y.re \leq -2.05 \cdot 10^{+83}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \mathbf{elif}\;y.re \leq -1.5 \cdot 10^{-120}:\\ \;\;\;\;\frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im}\\ \mathbf{elif}\;y.re \leq 4 \cdot 10^{-130}:\\ \;\;\;\;\frac{x.im}{y.im \cdot \frac{y.im}{y.re}} - \frac{x.re}{y.im}\\ \mathbf{elif}\;y.re \leq 2 \cdot 10^{+70}:\\ \;\;\;\;\frac{y.re \cdot x.im - y.im \cdot x.re}{y.re \cdot y.re + y.im \cdot y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \end{array} \]

Alternative 8: 69.7% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{-x.re}{y.im}\\ \mathbf{if}\;y.im \leq -18000000:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y.im \leq -5.1 \cdot 10^{-65}:\\ \;\;\;\;\frac{y.re \cdot x.im}{y.re \cdot y.re + y.im \cdot y.im}\\ \mathbf{elif}\;y.im \leq -9 \cdot 10^{-103} \lor \neg \left(y.im \leq 5.2 \cdot 10^{-36}\right):\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0 (/ (- x.re) y.im)))
   (if (<= y.im -18000000.0)
     t_0
     (if (<= y.im -5.1e-65)
       (/ (* y.re x.im) (+ (* y.re y.re) (* y.im y.im)))
       (if (or (<= y.im -9e-103) (not (<= y.im 5.2e-36)))
         t_0
         (* (/ 1.0 y.re) (- x.im (/ x.re (/ y.re y.im)))))))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double t_0 = -x_46_re / y_46_im;
	double tmp;
	if (y_46_im <= -18000000.0) {
		tmp = t_0;
	} else if (y_46_im <= -5.1e-65) {
		tmp = (y_46_re * x_46_im) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	} else if ((y_46_im <= -9e-103) || !(y_46_im <= 5.2e-36)) {
		tmp = t_0;
	} else {
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	}
	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) :: t_0
    real(8) :: tmp
    t_0 = -x_46re / y_46im
    if (y_46im <= (-18000000.0d0)) then
        tmp = t_0
    else if (y_46im <= (-5.1d-65)) then
        tmp = (y_46re * x_46im) / ((y_46re * y_46re) + (y_46im * y_46im))
    else if ((y_46im <= (-9d-103)) .or. (.not. (y_46im <= 5.2d-36))) then
        tmp = t_0
    else
        tmp = (1.0d0 / y_46re) * (x_46im - (x_46re / (y_46re / y_46im)))
    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 t_0 = -x_46_re / y_46_im;
	double tmp;
	if (y_46_im <= -18000000.0) {
		tmp = t_0;
	} else if (y_46_im <= -5.1e-65) {
		tmp = (y_46_re * x_46_im) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	} else if ((y_46_im <= -9e-103) || !(y_46_im <= 5.2e-36)) {
		tmp = t_0;
	} else {
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	}
	return tmp;
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	t_0 = -x_46_re / y_46_im
	tmp = 0
	if y_46_im <= -18000000.0:
		tmp = t_0
	elif y_46_im <= -5.1e-65:
		tmp = (y_46_re * x_46_im) / ((y_46_re * y_46_re) + (y_46_im * y_46_im))
	elif (y_46_im <= -9e-103) or not (y_46_im <= 5.2e-36):
		tmp = t_0
	else:
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)))
	return tmp
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = Float64(Float64(-x_46_re) / y_46_im)
	tmp = 0.0
	if (y_46_im <= -18000000.0)
		tmp = t_0;
	elseif (y_46_im <= -5.1e-65)
		tmp = Float64(Float64(y_46_re * x_46_im) / Float64(Float64(y_46_re * y_46_re) + Float64(y_46_im * y_46_im)));
	elseif ((y_46_im <= -9e-103) || !(y_46_im <= 5.2e-36))
		tmp = t_0;
	else
		tmp = Float64(Float64(1.0 / y_46_re) * Float64(x_46_im - Float64(x_46_re / Float64(y_46_re / y_46_im))));
	end
	return tmp
end
function tmp_2 = code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = -x_46_re / y_46_im;
	tmp = 0.0;
	if (y_46_im <= -18000000.0)
		tmp = t_0;
	elseif (y_46_im <= -5.1e-65)
		tmp = (y_46_re * x_46_im) / ((y_46_re * y_46_re) + (y_46_im * y_46_im));
	elseif ((y_46_im <= -9e-103) || ~((y_46_im <= 5.2e-36)))
		tmp = t_0;
	else
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	end
	tmp_2 = tmp;
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[((-x$46$re) / y$46$im), $MachinePrecision]}, If[LessEqual[y$46$im, -18000000.0], t$95$0, If[LessEqual[y$46$im, -5.1e-65], N[(N[(y$46$re * x$46$im), $MachinePrecision] / N[(N[(y$46$re * y$46$re), $MachinePrecision] + N[(y$46$im * y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[Or[LessEqual[y$46$im, -9e-103], N[Not[LessEqual[y$46$im, 5.2e-36]], $MachinePrecision]], t$95$0, N[(N[(1.0 / y$46$re), $MachinePrecision] * N[(x$46$im - N[(x$46$re / N[(y$46$re / y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{-x.re}{y.im}\\
\mathbf{if}\;y.im \leq -18000000:\\
\;\;\;\;t_0\\

\mathbf{elif}\;y.im \leq -5.1 \cdot 10^{-65}:\\
\;\;\;\;\frac{y.re \cdot x.im}{y.re \cdot y.re + y.im \cdot y.im}\\

\mathbf{elif}\;y.im \leq -9 \cdot 10^{-103} \lor \neg \left(y.im \leq 5.2 \cdot 10^{-36}\right):\\
\;\;\;\;t_0\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y.im < -1.8e7 or -5.10000000000000001e-65 < y.im < -9e-103 or 5.2000000000000001e-36 < y.im

    1. Initial program 58.9%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in y.re around 0 69.8%

      \[\leadsto \color{blue}{-1 \cdot \frac{x.re}{y.im}} \]
    3. Step-by-step derivation
      1. associate-*r/69.8%

        \[\leadsto \color{blue}{\frac{-1 \cdot x.re}{y.im}} \]
      2. neg-mul-169.8%

        \[\leadsto \frac{\color{blue}{-x.re}}{y.im} \]
    4. Simplified69.8%

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

    if -1.8e7 < y.im < -5.10000000000000001e-65

    1. Initial program 92.9%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in x.im around inf 68.8%

      \[\leadsto \frac{\color{blue}{x.im \cdot y.re}}{y.re \cdot y.re + y.im \cdot y.im} \]
    3. Step-by-step derivation
      1. *-commutative68.8%

        \[\leadsto \frac{\color{blue}{y.re \cdot x.im}}{y.re \cdot y.re + y.im \cdot y.im} \]
    4. Simplified68.8%

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

    if -9e-103 < y.im < 5.2000000000000001e-36

    1. Initial program 74.9%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity74.9%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt74.9%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac74.8%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def74.8%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def83.2%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr83.2%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    4. Taylor expanded in y.re around inf 46.8%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im + -1 \cdot \frac{x.re \cdot y.im}{y.re}\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg46.8%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im + \color{blue}{\left(-\frac{x.re \cdot y.im}{y.re}\right)}\right) \]
      2. unsub-neg46.8%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re \cdot y.im}{y.re}\right)} \]
      3. associate-/l*47.8%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im - \color{blue}{\frac{x.re}{\frac{y.re}{y.im}}}\right) \]
    6. Simplified47.8%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)} \]
    7. Taylor expanded in y.re around inf 88.5%

      \[\leadsto \color{blue}{\frac{1}{y.re}} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right) \]
  3. Recombined 3 regimes into one program.
  4. Final simplification77.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y.im \leq -18000000:\\ \;\;\;\;\frac{-x.re}{y.im}\\ \mathbf{elif}\;y.im \leq -5.1 \cdot 10^{-65}:\\ \;\;\;\;\frac{y.re \cdot x.im}{y.re \cdot y.re + y.im \cdot y.im}\\ \mathbf{elif}\;y.im \leq -9 \cdot 10^{-103} \lor \neg \left(y.im \leq 5.2 \cdot 10^{-36}\right):\\ \;\;\;\;\frac{-x.re}{y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \end{array} \]

Alternative 9: 70.4% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := y.re \cdot y.re + y.im \cdot y.im\\ t_1 := \frac{-x.re}{y.im}\\ \mathbf{if}\;y.im \leq -180000:\\ \;\;\;\;t_1\\ \mathbf{elif}\;y.im \leq -1.4 \cdot 10^{-64}:\\ \;\;\;\;\frac{y.re \cdot x.im}{t_0}\\ \mathbf{elif}\;y.im \leq -9 \cdot 10^{-103}:\\ \;\;\;\;\frac{y.im \cdot \left(-x.re\right)}{t_0}\\ \mathbf{elif}\;y.im \leq 1.6 \cdot 10^{-34}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \mathbf{else}:\\ \;\;\;\;t_1\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (let* ((t_0 (+ (* y.re y.re) (* y.im y.im))) (t_1 (/ (- x.re) y.im)))
   (if (<= y.im -180000.0)
     t_1
     (if (<= y.im -1.4e-64)
       (/ (* y.re x.im) t_0)
       (if (<= y.im -9e-103)
         (/ (* y.im (- x.re)) t_0)
         (if (<= y.im 1.6e-34)
           (* (/ 1.0 y.re) (- x.im (/ x.re (/ y.re y.im))))
           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_re * y_46_re) + (y_46_im * y_46_im);
	double t_1 = -x_46_re / y_46_im;
	double tmp;
	if (y_46_im <= -180000.0) {
		tmp = t_1;
	} else if (y_46_im <= -1.4e-64) {
		tmp = (y_46_re * x_46_im) / t_0;
	} else if (y_46_im <= -9e-103) {
		tmp = (y_46_im * -x_46_re) / t_0;
	} else if (y_46_im <= 1.6e-34) {
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	} else {
		tmp = t_1;
	}
	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) :: t_0
    real(8) :: t_1
    real(8) :: tmp
    t_0 = (y_46re * y_46re) + (y_46im * y_46im)
    t_1 = -x_46re / y_46im
    if (y_46im <= (-180000.0d0)) then
        tmp = t_1
    else if (y_46im <= (-1.4d-64)) then
        tmp = (y_46re * x_46im) / t_0
    else if (y_46im <= (-9d-103)) then
        tmp = (y_46im * -x_46re) / t_0
    else if (y_46im <= 1.6d-34) then
        tmp = (1.0d0 / y_46re) * (x_46im - (x_46re / (y_46re / y_46im)))
    else
        tmp = t_1
    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 t_0 = (y_46_re * y_46_re) + (y_46_im * y_46_im);
	double t_1 = -x_46_re / y_46_im;
	double tmp;
	if (y_46_im <= -180000.0) {
		tmp = t_1;
	} else if (y_46_im <= -1.4e-64) {
		tmp = (y_46_re * x_46_im) / t_0;
	} else if (y_46_im <= -9e-103) {
		tmp = (y_46_im * -x_46_re) / t_0;
	} else if (y_46_im <= 1.6e-34) {
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	} else {
		tmp = t_1;
	}
	return tmp;
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	t_0 = (y_46_re * y_46_re) + (y_46_im * y_46_im)
	t_1 = -x_46_re / y_46_im
	tmp = 0
	if y_46_im <= -180000.0:
		tmp = t_1
	elif y_46_im <= -1.4e-64:
		tmp = (y_46_re * x_46_im) / t_0
	elif y_46_im <= -9e-103:
		tmp = (y_46_im * -x_46_re) / t_0
	elif y_46_im <= 1.6e-34:
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)))
	else:
		tmp = t_1
	return tmp
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = Float64(Float64(y_46_re * y_46_re) + Float64(y_46_im * y_46_im))
	t_1 = Float64(Float64(-x_46_re) / y_46_im)
	tmp = 0.0
	if (y_46_im <= -180000.0)
		tmp = t_1;
	elseif (y_46_im <= -1.4e-64)
		tmp = Float64(Float64(y_46_re * x_46_im) / t_0);
	elseif (y_46_im <= -9e-103)
		tmp = Float64(Float64(y_46_im * Float64(-x_46_re)) / t_0);
	elseif (y_46_im <= 1.6e-34)
		tmp = Float64(Float64(1.0 / y_46_re) * Float64(x_46_im - Float64(x_46_re / Float64(y_46_re / y_46_im))));
	else
		tmp = t_1;
	end
	return tmp
end
function tmp_2 = code(x_46_re, x_46_im, y_46_re, y_46_im)
	t_0 = (y_46_re * y_46_re) + (y_46_im * y_46_im);
	t_1 = -x_46_re / y_46_im;
	tmp = 0.0;
	if (y_46_im <= -180000.0)
		tmp = t_1;
	elseif (y_46_im <= -1.4e-64)
		tmp = (y_46_re * x_46_im) / t_0;
	elseif (y_46_im <= -9e-103)
		tmp = (y_46_im * -x_46_re) / t_0;
	elseif (y_46_im <= 1.6e-34)
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	else
		tmp = t_1;
	end
	tmp_2 = tmp;
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := Block[{t$95$0 = N[(N[(y$46$re * y$46$re), $MachinePrecision] + N[(y$46$im * y$46$im), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[((-x$46$re) / y$46$im), $MachinePrecision]}, If[LessEqual[y$46$im, -180000.0], t$95$1, If[LessEqual[y$46$im, -1.4e-64], N[(N[(y$46$re * x$46$im), $MachinePrecision] / t$95$0), $MachinePrecision], If[LessEqual[y$46$im, -9e-103], N[(N[(y$46$im * (-x$46$re)), $MachinePrecision] / t$95$0), $MachinePrecision], If[LessEqual[y$46$im, 1.6e-34], N[(N[(1.0 / y$46$re), $MachinePrecision] * N[(x$46$im - N[(x$46$re / N[(y$46$re / y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], t$95$1]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := y.re \cdot y.re + y.im \cdot y.im\\
t_1 := \frac{-x.re}{y.im}\\
\mathbf{if}\;y.im \leq -180000:\\
\;\;\;\;t_1\\

\mathbf{elif}\;y.im \leq -1.4 \cdot 10^{-64}:\\
\;\;\;\;\frac{y.re \cdot x.im}{t_0}\\

\mathbf{elif}\;y.im \leq -9 \cdot 10^{-103}:\\
\;\;\;\;\frac{y.im \cdot \left(-x.re\right)}{t_0}\\

\mathbf{elif}\;y.im \leq 1.6 \cdot 10^{-34}:\\
\;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\

\mathbf{else}:\\
\;\;\;\;t_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if y.im < -1.8e5 or 1.60000000000000001e-34 < y.im

    1. Initial program 56.5%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in y.re around 0 70.4%

      \[\leadsto \color{blue}{-1 \cdot \frac{x.re}{y.im}} \]
    3. Step-by-step derivation
      1. associate-*r/70.4%

        \[\leadsto \color{blue}{\frac{-1 \cdot x.re}{y.im}} \]
      2. neg-mul-170.4%

        \[\leadsto \frac{\color{blue}{-x.re}}{y.im} \]
    4. Simplified70.4%

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

    if -1.8e5 < y.im < -1.40000000000000002e-64

    1. Initial program 92.9%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in x.im around inf 68.8%

      \[\leadsto \frac{\color{blue}{x.im \cdot y.re}}{y.re \cdot y.re + y.im \cdot y.im} \]
    3. Step-by-step derivation
      1. *-commutative68.8%

        \[\leadsto \frac{\color{blue}{y.re \cdot x.im}}{y.re \cdot y.re + y.im \cdot y.im} \]
    4. Simplified68.8%

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

    if -1.40000000000000002e-64 < y.im < -9e-103

    1. Initial program 89.7%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in x.im around 0 70.8%

      \[\leadsto \frac{\color{blue}{-1 \cdot \left(x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
    3. Step-by-step derivation
      1. associate-*r*70.8%

        \[\leadsto \frac{\color{blue}{\left(-1 \cdot x.re\right) \cdot y.im}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. neg-mul-170.8%

        \[\leadsto \frac{\color{blue}{\left(-x.re\right)} \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
      3. *-commutative70.8%

        \[\leadsto \frac{\color{blue}{y.im \cdot \left(-x.re\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
    4. Simplified70.8%

      \[\leadsto \frac{\color{blue}{y.im \cdot \left(-x.re\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]

    if -9e-103 < y.im < 1.60000000000000001e-34

    1. Initial program 74.9%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity74.9%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt74.9%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac74.8%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def74.8%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def83.2%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr83.2%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    4. Taylor expanded in y.re around inf 46.8%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im + -1 \cdot \frac{x.re \cdot y.im}{y.re}\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg46.8%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im + \color{blue}{\left(-\frac{x.re \cdot y.im}{y.re}\right)}\right) \]
      2. unsub-neg46.8%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re \cdot y.im}{y.re}\right)} \]
      3. associate-/l*47.8%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im - \color{blue}{\frac{x.re}{\frac{y.re}{y.im}}}\right) \]
    6. Simplified47.8%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)} \]
    7. Taylor expanded in y.re around inf 88.5%

      \[\leadsto \color{blue}{\frac{1}{y.re}} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right) \]
  3. Recombined 4 regimes into one program.
  4. Final simplification77.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y.im \leq -180000:\\ \;\;\;\;\frac{-x.re}{y.im}\\ \mathbf{elif}\;y.im \leq -1.4 \cdot 10^{-64}:\\ \;\;\;\;\frac{y.re \cdot x.im}{y.re \cdot y.re + y.im \cdot y.im}\\ \mathbf{elif}\;y.im \leq -9 \cdot 10^{-103}:\\ \;\;\;\;\frac{y.im \cdot \left(-x.re\right)}{y.re \cdot y.re + y.im \cdot y.im}\\ \mathbf{elif}\;y.im \leq 1.6 \cdot 10^{-34}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{-x.re}{y.im}\\ \end{array} \]

Alternative 10: 72.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y.im \leq -1250000000 \lor \neg \left(y.im \leq 3 \cdot 10^{-35}\right):\\ \;\;\;\;\frac{-x.re}{y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (if (or (<= y.im -1250000000.0) (not (<= y.im 3e-35)))
   (/ (- x.re) y.im)
   (* (/ 1.0 y.re) (- x.im (/ x.re (/ y.re y.im))))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double tmp;
	if ((y_46_im <= -1250000000.0) || !(y_46_im <= 3e-35)) {
		tmp = -x_46_re / y_46_im;
	} else {
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	}
	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_46im <= (-1250000000.0d0)) .or. (.not. (y_46im <= 3d-35))) then
        tmp = -x_46re / y_46im
    else
        tmp = (1.0d0 / y_46re) * (x_46im - (x_46re / (y_46re / y_46im)))
    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_im <= -1250000000.0) || !(y_46_im <= 3e-35)) {
		tmp = -x_46_re / y_46_im;
	} else {
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	}
	return tmp;
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	tmp = 0
	if (y_46_im <= -1250000000.0) or not (y_46_im <= 3e-35):
		tmp = -x_46_re / y_46_im
	else:
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)))
	return tmp
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	tmp = 0.0
	if ((y_46_im <= -1250000000.0) || !(y_46_im <= 3e-35))
		tmp = Float64(Float64(-x_46_re) / y_46_im);
	else
		tmp = Float64(Float64(1.0 / y_46_re) * Float64(x_46_im - Float64(x_46_re / Float64(y_46_re / y_46_im))));
	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_im <= -1250000000.0) || ~((y_46_im <= 3e-35)))
		tmp = -x_46_re / y_46_im;
	else
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	end
	tmp_2 = tmp;
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := If[Or[LessEqual[y$46$im, -1250000000.0], N[Not[LessEqual[y$46$im, 3e-35]], $MachinePrecision]], N[((-x$46$re) / y$46$im), $MachinePrecision], N[(N[(1.0 / y$46$re), $MachinePrecision] * N[(x$46$im - N[(x$46$re / N[(y$46$re / y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y.im \leq -1250000000 \lor \neg \left(y.im \leq 3 \cdot 10^{-35}\right):\\
\;\;\;\;\frac{-x.re}{y.im}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y.im < -1.25e9 or 2.99999999999999989e-35 < y.im

    1. Initial program 56.5%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in y.re around 0 70.4%

      \[\leadsto \color{blue}{-1 \cdot \frac{x.re}{y.im}} \]
    3. Step-by-step derivation
      1. associate-*r/70.4%

        \[\leadsto \color{blue}{\frac{-1 \cdot x.re}{y.im}} \]
      2. neg-mul-170.4%

        \[\leadsto \frac{\color{blue}{-x.re}}{y.im} \]
    4. Simplified70.4%

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

    if -1.25e9 < y.im < 2.99999999999999989e-35

    1. Initial program 78.2%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity78.2%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt78.2%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac78.1%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def78.1%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def84.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr84.9%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    4. Taylor expanded in y.re around inf 42.7%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im + -1 \cdot \frac{x.re \cdot y.im}{y.re}\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg42.7%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im + \color{blue}{\left(-\frac{x.re \cdot y.im}{y.re}\right)}\right) \]
      2. unsub-neg42.7%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re \cdot y.im}{y.re}\right)} \]
      3. associate-/l*43.4%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im - \color{blue}{\frac{x.re}{\frac{y.re}{y.im}}}\right) \]
    6. Simplified43.4%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)} \]
    7. Taylor expanded in y.re around inf 80.1%

      \[\leadsto \color{blue}{\frac{1}{y.re}} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification75.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y.im \leq -1250000000 \lor \neg \left(y.im \leq 3 \cdot 10^{-35}\right):\\ \;\;\;\;\frac{-x.re}{y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \end{array} \]

Alternative 11: 75.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y.im \leq -5.6 \cdot 10^{-91} \lor \neg \left(y.im \leq 3.5 \cdot 10^{-35}\right):\\ \;\;\;\;\frac{x.im}{y.im \cdot \frac{y.im}{y.re}} - \frac{x.re}{y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (if (or (<= y.im -5.6e-91) (not (<= y.im 3.5e-35)))
   (- (/ x.im (* y.im (/ y.im y.re))) (/ x.re y.im))
   (* (/ 1.0 y.re) (- x.im (/ x.re (/ y.re y.im))))))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double tmp;
	if ((y_46_im <= -5.6e-91) || !(y_46_im <= 3.5e-35)) {
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	} else {
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	}
	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_46im <= (-5.6d-91)) .or. (.not. (y_46im <= 3.5d-35))) then
        tmp = (x_46im / (y_46im * (y_46im / y_46re))) - (x_46re / y_46im)
    else
        tmp = (1.0d0 / y_46re) * (x_46im - (x_46re / (y_46re / y_46im)))
    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_im <= -5.6e-91) || !(y_46_im <= 3.5e-35)) {
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	} else {
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	}
	return tmp;
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	tmp = 0
	if (y_46_im <= -5.6e-91) or not (y_46_im <= 3.5e-35):
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im)
	else:
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)))
	return tmp
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	tmp = 0.0
	if ((y_46_im <= -5.6e-91) || !(y_46_im <= 3.5e-35))
		tmp = Float64(Float64(x_46_im / Float64(y_46_im * Float64(y_46_im / y_46_re))) - Float64(x_46_re / y_46_im));
	else
		tmp = Float64(Float64(1.0 / y_46_re) * Float64(x_46_im - Float64(x_46_re / Float64(y_46_re / y_46_im))));
	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_im <= -5.6e-91) || ~((y_46_im <= 3.5e-35)))
		tmp = (x_46_im / (y_46_im * (y_46_im / y_46_re))) - (x_46_re / y_46_im);
	else
		tmp = (1.0 / y_46_re) * (x_46_im - (x_46_re / (y_46_re / y_46_im)));
	end
	tmp_2 = tmp;
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := If[Or[LessEqual[y$46$im, -5.6e-91], N[Not[LessEqual[y$46$im, 3.5e-35]], $MachinePrecision]], N[(N[(x$46$im / N[(y$46$im * N[(y$46$im / y$46$re), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(x$46$re / y$46$im), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 / y$46$re), $MachinePrecision] * N[(x$46$im - N[(x$46$re / N[(y$46$re / y$46$im), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y.im \leq -5.6 \cdot 10^{-91} \lor \neg \left(y.im \leq 3.5 \cdot 10^{-35}\right):\\
\;\;\;\;\frac{x.im}{y.im \cdot \frac{y.im}{y.re}} - \frac{x.re}{y.im}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y.im < -5.6e-91 or 3.49999999999999996e-35 < y.im

    1. Initial program 61.8%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in y.re around 0 74.6%

      \[\leadsto \color{blue}{-1 \cdot \frac{x.re}{y.im} + \frac{x.im \cdot y.re}{{y.im}^{2}}} \]
    3. Step-by-step derivation
      1. +-commutative74.6%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{{y.im}^{2}} + -1 \cdot \frac{x.re}{y.im}} \]
      2. mul-1-neg74.6%

        \[\leadsto \frac{x.im \cdot y.re}{{y.im}^{2}} + \color{blue}{\left(-\frac{x.re}{y.im}\right)} \]
      3. unsub-neg74.6%

        \[\leadsto \color{blue}{\frac{x.im \cdot y.re}{{y.im}^{2}} - \frac{x.re}{y.im}} \]
      4. associate-/l*74.2%

        \[\leadsto \color{blue}{\frac{x.im}{\frac{{y.im}^{2}}{y.re}}} - \frac{x.re}{y.im} \]
    4. Simplified74.2%

      \[\leadsto \color{blue}{\frac{x.im}{\frac{{y.im}^{2}}{y.re}} - \frac{x.re}{y.im}} \]
    5. Step-by-step derivation
      1. pow274.2%

        \[\leadsto \frac{x.im}{\frac{\color{blue}{y.im \cdot y.im}}{y.re}} - \frac{x.re}{y.im} \]
      2. *-un-lft-identity74.2%

        \[\leadsto \frac{x.im}{\frac{y.im \cdot y.im}{\color{blue}{1 \cdot y.re}}} - \frac{x.re}{y.im} \]
      3. times-frac75.4%

        \[\leadsto \frac{x.im}{\color{blue}{\frac{y.im}{1} \cdot \frac{y.im}{y.re}}} - \frac{x.re}{y.im} \]
    6. Applied egg-rr75.4%

      \[\leadsto \frac{x.im}{\color{blue}{\frac{y.im}{1} \cdot \frac{y.im}{y.re}}} - \frac{x.re}{y.im} \]

    if -5.6e-91 < y.im < 3.49999999999999996e-35

    1. Initial program 74.9%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Step-by-step derivation
      1. *-un-lft-identity74.9%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
      2. add-sqr-sqrt74.9%

        \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      3. times-frac74.8%

        \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
      4. hypot-def74.8%

        \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
      5. hypot-def82.9%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    3. Applied egg-rr82.9%

      \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
    4. Taylor expanded in y.re around inf 45.1%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im + -1 \cdot \frac{x.re \cdot y.im}{y.re}\right)} \]
    5. Step-by-step derivation
      1. mul-1-neg45.1%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im + \color{blue}{\left(-\frac{x.re \cdot y.im}{y.re}\right)}\right) \]
      2. unsub-neg45.1%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re \cdot y.im}{y.re}\right)} \]
      3. associate-/l*46.0%

        \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \left(x.im - \color{blue}{\frac{x.re}{\frac{y.re}{y.im}}}\right) \]
    6. Simplified46.0%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)} \]
    7. Taylor expanded in y.re around inf 87.2%

      \[\leadsto \color{blue}{\frac{1}{y.re}} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y.im \leq -5.6 \cdot 10^{-91} \lor \neg \left(y.im \leq 3.5 \cdot 10^{-35}\right):\\ \;\;\;\;\frac{x.im}{y.im \cdot \frac{y.im}{y.re}} - \frac{x.re}{y.im}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{y.re} \cdot \left(x.im - \frac{x.re}{\frac{y.re}{y.im}}\right)\\ \end{array} \]

Alternative 12: 64.6% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y.re \leq -8.4 \cdot 10^{-35} \lor \neg \left(y.re \leq 8.4 \cdot 10^{-21}\right):\\ \;\;\;\;\frac{x.im}{y.re}\\ \mathbf{else}:\\ \;\;\;\;\frac{-x.re}{y.im}\\ \end{array} \end{array} \]
(FPCore (x.re x.im y.re y.im)
 :precision binary64
 (if (or (<= y.re -8.4e-35) (not (<= y.re 8.4e-21)))
   (/ x.im y.re)
   (/ (- x.re) y.im)))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	double tmp;
	if ((y_46_re <= -8.4e-35) || !(y_46_re <= 8.4e-21)) {
		tmp = x_46_im / y_46_re;
	} else {
		tmp = -x_46_re / y_46_im;
	}
	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 <= (-8.4d-35)) .or. (.not. (y_46re <= 8.4d-21))) then
        tmp = x_46im / y_46re
    else
        tmp = -x_46re / y_46im
    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 <= -8.4e-35) || !(y_46_re <= 8.4e-21)) {
		tmp = x_46_im / y_46_re;
	} else {
		tmp = -x_46_re / y_46_im;
	}
	return tmp;
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	tmp = 0
	if (y_46_re <= -8.4e-35) or not (y_46_re <= 8.4e-21):
		tmp = x_46_im / y_46_re
	else:
		tmp = -x_46_re / y_46_im
	return tmp
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	tmp = 0.0
	if ((y_46_re <= -8.4e-35) || !(y_46_re <= 8.4e-21))
		tmp = Float64(x_46_im / y_46_re);
	else
		tmp = Float64(Float64(-x_46_re) / y_46_im);
	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 <= -8.4e-35) || ~((y_46_re <= 8.4e-21)))
		tmp = x_46_im / y_46_re;
	else
		tmp = -x_46_re / y_46_im;
	end
	tmp_2 = tmp;
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := If[Or[LessEqual[y$46$re, -8.4e-35], N[Not[LessEqual[y$46$re, 8.4e-21]], $MachinePrecision]], N[(x$46$im / y$46$re), $MachinePrecision], N[((-x$46$re) / y$46$im), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y.re \leq -8.4 \cdot 10^{-35} \lor \neg \left(y.re \leq 8.4 \cdot 10^{-21}\right):\\
\;\;\;\;\frac{x.im}{y.re}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y.re < -8.3999999999999999e-35 or 8.4000000000000005e-21 < y.re

    1. Initial program 56.2%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in y.re around inf 66.3%

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

    if -8.3999999999999999e-35 < y.re < 8.4000000000000005e-21

    1. Initial program 77.3%

      \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. Taylor expanded in y.re around 0 67.0%

      \[\leadsto \color{blue}{-1 \cdot \frac{x.re}{y.im}} \]
    3. Step-by-step derivation
      1. associate-*r/67.0%

        \[\leadsto \color{blue}{\frac{-1 \cdot x.re}{y.im}} \]
      2. neg-mul-167.0%

        \[\leadsto \frac{\color{blue}{-x.re}}{y.im} \]
    4. Simplified67.0%

      \[\leadsto \color{blue}{\frac{-x.re}{y.im}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification66.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y.re \leq -8.4 \cdot 10^{-35} \lor \neg \left(y.re \leq 8.4 \cdot 10^{-21}\right):\\ \;\;\;\;\frac{x.im}{y.re}\\ \mathbf{else}:\\ \;\;\;\;\frac{-x.re}{y.im}\\ \end{array} \]

Alternative 13: 10.0% accurate, 5.0× 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 67.1%

    \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
  2. Step-by-step derivation
    1. *-un-lft-identity67.1%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}}{y.re \cdot y.re + y.im \cdot y.im} \]
    2. add-sqr-sqrt67.1%

      \[\leadsto \frac{1 \cdot \left(x.im \cdot y.re - x.re \cdot y.im\right)}{\color{blue}{\sqrt{y.re \cdot y.re + y.im \cdot y.im} \cdot \sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
    3. times-frac67.1%

      \[\leadsto \color{blue}{\frac{1}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}} \]
    4. hypot-def67.1%

      \[\leadsto \frac{1}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}} \]
    5. hypot-def77.4%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\color{blue}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
  3. Applied egg-rr77.4%

    \[\leadsto \color{blue}{\frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \frac{x.im \cdot y.re - x.re \cdot y.im}{\mathsf{hypot}\left(y.re, y.im\right)}} \]
  4. Taylor expanded in y.re around -inf 29.3%

    \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(-1 \cdot x.im\right)} \]
  5. Step-by-step derivation
    1. mul-1-neg29.3%

      \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(-x.im\right)} \]
  6. Simplified29.3%

    \[\leadsto \frac{1}{\mathsf{hypot}\left(y.re, y.im\right)} \cdot \color{blue}{\left(-x.im\right)} \]
  7. Taylor expanded in y.im around -inf 8.7%

    \[\leadsto \color{blue}{\frac{x.im}{y.im}} \]
  8. Final simplification8.7%

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

Alternative 14: 42.1% accurate, 5.0× speedup?

\[\begin{array}{l} \\ \frac{x.im}{y.re} \end{array} \]
(FPCore (x.re x.im y.re y.im) :precision binary64 (/ x.im y.re))
double code(double x_46_re, double x_46_im, double y_46_re, double y_46_im) {
	return x_46_im / y_46_re;
}
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_46re
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_re;
}
def code(x_46_re, x_46_im, y_46_re, y_46_im):
	return x_46_im / y_46_re
function code(x_46_re, x_46_im, y_46_re, y_46_im)
	return Float64(x_46_im / y_46_re)
end
function tmp = code(x_46_re, x_46_im, y_46_re, y_46_im)
	tmp = x_46_im / y_46_re;
end
code[x$46$re_, x$46$im_, y$46$re_, y$46$im_] := N[(x$46$im / y$46$re), $MachinePrecision]
\begin{array}{l}

\\
\frac{x.im}{y.re}
\end{array}
Derivation
  1. Initial program 67.1%

    \[\frac{x.im \cdot y.re - x.re \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im} \]
  2. Taylor expanded in y.re around inf 38.4%

    \[\leadsto \color{blue}{\frac{x.im}{y.re}} \]
  3. Final simplification38.4%

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

Reproduce

?
herbie shell --seed 2023299 
(FPCore (x.re x.im y.re y.im)
  :name "_divideComplex, imaginary part"
  :precision binary64
  (/ (- (* x.im y.re) (* x.re y.im)) (+ (* y.re y.re) (* y.im y.im))))