\frac{x.re \cdot y.re + x.im \cdot y.im}{y.re \cdot y.re + y.im \cdot y.im}\begin{array}{l}
\mathbf{if}\;\frac{x.im \cdot y.im + x.re \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} = -\infty:\\
\;\;\;\;\frac{x.im}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}\\
\mathbf{elif}\;\frac{x.im \cdot y.im + x.re \cdot y.re}{y.re \cdot y.re + y.im \cdot y.im} \le 7.764290901790722 \cdot 10^{+281}:\\
\;\;\;\;\frac{\frac{x.im \cdot y.im + x.re \cdot y.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}\\
\mathbf{else}:\\
\;\;\;\;\frac{x.re}{\sqrt{y.re \cdot y.re + y.im \cdot y.im}}\\
\end{array}double f(double x_re, double x_im, double y_re, double y_im) {
double r2777275 = x_re;
double r2777276 = y_re;
double r2777277 = r2777275 * r2777276;
double r2777278 = x_im;
double r2777279 = y_im;
double r2777280 = r2777278 * r2777279;
double r2777281 = r2777277 + r2777280;
double r2777282 = r2777276 * r2777276;
double r2777283 = r2777279 * r2777279;
double r2777284 = r2777282 + r2777283;
double r2777285 = r2777281 / r2777284;
return r2777285;
}
double f(double x_re, double x_im, double y_re, double y_im) {
double r2777286 = x_im;
double r2777287 = y_im;
double r2777288 = r2777286 * r2777287;
double r2777289 = x_re;
double r2777290 = y_re;
double r2777291 = r2777289 * r2777290;
double r2777292 = r2777288 + r2777291;
double r2777293 = r2777290 * r2777290;
double r2777294 = r2777287 * r2777287;
double r2777295 = r2777293 + r2777294;
double r2777296 = r2777292 / r2777295;
double r2777297 = -inf.0;
bool r2777298 = r2777296 <= r2777297;
double r2777299 = sqrt(r2777295);
double r2777300 = r2777286 / r2777299;
double r2777301 = 7.764290901790722e+281;
bool r2777302 = r2777296 <= r2777301;
double r2777303 = r2777292 / r2777299;
double r2777304 = r2777303 / r2777299;
double r2777305 = r2777289 / r2777299;
double r2777306 = r2777302 ? r2777304 : r2777305;
double r2777307 = r2777298 ? r2777300 : r2777306;
return r2777307;
}



Bits error versus x.re



Bits error versus x.im



Bits error versus y.re



Bits error versus y.im
Results
if (/ (+ (* x.re y.re) (* x.im y.im)) (+ (* y.re y.re) (* y.im y.im))) < -inf.0Initial program 60.5
rmApplied add-sqr-sqrt60.5
Applied associate-/r*60.5
Taylor expanded around 0 53.1
if -inf.0 < (/ (+ (* x.re y.re) (* x.im y.im)) (+ (* y.re y.re) (* y.im y.im))) < 7.764290901790722e+281Initial program 11.1
rmApplied add-sqr-sqrt11.1
Applied associate-/r*11.0
if 7.764290901790722e+281 < (/ (+ (* x.re y.re) (* x.im y.im)) (+ (* y.re y.re) (* y.im y.im))) Initial program 61.2
rmApplied add-sqr-sqrt61.2
Applied associate-/r*61.2
Taylor expanded around inf 59.7
Final simplification25.0
herbie shell --seed 2019107
(FPCore (x.re x.im y.re y.im)
:name "_divideComplex, real part"
(/ (+ (* x.re y.re) (* x.im y.im)) (+ (* y.re y.re) (* y.im y.im))))