Complex division, imag part

Percentage Accurate: 61.6% → 83.5%
Time: 8.7s
Alternatives: 9
Speedup: 1.5×

Specification

?
\[\begin{array}{l} \\ \frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \end{array} \]
(FPCore (a b c d)
 :precision binary64
 (/ (- (* b c) (* a d)) (+ (* c c) (* d d))))
double code(double a, double b, double c, double d) {
	return ((b * c) - (a * d)) / ((c * c) + (d * d));
}
real(8) function code(a, b, c, d)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8), intent (in) :: d
    code = ((b * c) - (a * d)) / ((c * c) + (d * d))
end function
public static double code(double a, double b, double c, double d) {
	return ((b * c) - (a * d)) / ((c * c) + (d * d));
}
def code(a, b, c, d):
	return ((b * c) - (a * d)) / ((c * c) + (d * d))
function code(a, b, c, d)
	return Float64(Float64(Float64(b * c) - Float64(a * d)) / Float64(Float64(c * c) + Float64(d * d)))
end
function tmp = code(a, b, c, d)
	tmp = ((b * c) - (a * d)) / ((c * c) + (d * d));
end
code[a_, b_, c_, d_] := N[(N[(N[(b * c), $MachinePrecision] - N[(a * d), $MachinePrecision]), $MachinePrecision] / N[(N[(c * c), $MachinePrecision] + N[(d * d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 9 alternatives:

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

Initial Program: 61.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \end{array} \]
(FPCore (a b c d)
 :precision binary64
 (/ (- (* b c) (* a d)) (+ (* c c) (* d d))))
double code(double a, double b, double c, double d) {
	return ((b * c) - (a * d)) / ((c * c) + (d * d));
}
real(8) function code(a, b, c, d)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    real(8), intent (in) :: d
    code = ((b * c) - (a * d)) / ((c * c) + (d * d))
end function
public static double code(double a, double b, double c, double d) {
	return ((b * c) - (a * d)) / ((c * c) + (d * d));
}
def code(a, b, c, d):
	return ((b * c) - (a * d)) / ((c * c) + (d * d))
function code(a, b, c, d)
	return Float64(Float64(Float64(b * c) - Float64(a * d)) / Float64(Float64(c * c) + Float64(d * d)))
end
function tmp = code(a, b, c, d)
	tmp = ((b * c) - (a * d)) / ((c * c) + (d * d));
end
code[a_, b_, c_, d_] := N[(N[(N[(b * c), $MachinePrecision] - N[(a * d), $MachinePrecision]), $MachinePrecision] / N[(N[(c * c), $MachinePrecision] + N[(d * d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d}
\end{array}

Alternative 1: 83.5% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(d, d, c \cdot c\right)\\ t_1 := \frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\ \mathbf{if}\;d \leq -4.2 \cdot 10^{+126}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;d \leq -2.32 \cdot 10^{-73}:\\ \;\;\;\;\frac{b \cdot c - d \cdot a}{\mathsf{fma}\left(c, c, d \cdot d\right)}\\ \mathbf{elif}\;d \leq 2 \cdot 10^{-121}:\\ \;\;\;\;\frac{\mathsf{fma}\left(d \cdot a, \frac{-1}{c}, b\right)}{c}\\ \mathbf{elif}\;d \leq 5 \cdot 10^{+146}:\\ \;\;\;\;\mathsf{fma}\left(-a, \frac{d}{t\_0}, \frac{b \cdot c}{t\_0}\right)\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \end{array} \]
(FPCore (a b c d)
 :precision binary64
 (let* ((t_0 (fma d d (* c c))) (t_1 (/ (fma b (/ c d) (- a)) d)))
   (if (<= d -4.2e+126)
     t_1
     (if (<= d -2.32e-73)
       (/ (- (* b c) (* d a)) (fma c c (* d d)))
       (if (<= d 2e-121)
         (/ (fma (* d a) (/ -1.0 c) b) c)
         (if (<= d 5e+146) (fma (- a) (/ d t_0) (/ (* b c) t_0)) t_1))))))
double code(double a, double b, double c, double d) {
	double t_0 = fma(d, d, (c * c));
	double t_1 = fma(b, (c / d), -a) / d;
	double tmp;
	if (d <= -4.2e+126) {
		tmp = t_1;
	} else if (d <= -2.32e-73) {
		tmp = ((b * c) - (d * a)) / fma(c, c, (d * d));
	} else if (d <= 2e-121) {
		tmp = fma((d * a), (-1.0 / c), b) / c;
	} else if (d <= 5e+146) {
		tmp = fma(-a, (d / t_0), ((b * c) / t_0));
	} else {
		tmp = t_1;
	}
	return tmp;
}
function code(a, b, c, d)
	t_0 = fma(d, d, Float64(c * c))
	t_1 = Float64(fma(b, Float64(c / d), Float64(-a)) / d)
	tmp = 0.0
	if (d <= -4.2e+126)
		tmp = t_1;
	elseif (d <= -2.32e-73)
		tmp = Float64(Float64(Float64(b * c) - Float64(d * a)) / fma(c, c, Float64(d * d)));
	elseif (d <= 2e-121)
		tmp = Float64(fma(Float64(d * a), Float64(-1.0 / c), b) / c);
	elseif (d <= 5e+146)
		tmp = fma(Float64(-a), Float64(d / t_0), Float64(Float64(b * c) / t_0));
	else
		tmp = t_1;
	end
	return tmp
end
code[a_, b_, c_, d_] := Block[{t$95$0 = N[(d * d + N[(c * c), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(b * N[(c / d), $MachinePrecision] + (-a)), $MachinePrecision] / d), $MachinePrecision]}, If[LessEqual[d, -4.2e+126], t$95$1, If[LessEqual[d, -2.32e-73], N[(N[(N[(b * c), $MachinePrecision] - N[(d * a), $MachinePrecision]), $MachinePrecision] / N[(c * c + N[(d * d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[d, 2e-121], N[(N[(N[(d * a), $MachinePrecision] * N[(-1.0 / c), $MachinePrecision] + b), $MachinePrecision] / c), $MachinePrecision], If[LessEqual[d, 5e+146], N[((-a) * N[(d / t$95$0), $MachinePrecision] + N[(N[(b * c), $MachinePrecision] / t$95$0), $MachinePrecision]), $MachinePrecision], t$95$1]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(d, d, c \cdot c\right)\\
t_1 := \frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\
\mathbf{if}\;d \leq -4.2 \cdot 10^{+126}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;d \leq -2.32 \cdot 10^{-73}:\\
\;\;\;\;\frac{b \cdot c - d \cdot a}{\mathsf{fma}\left(c, c, d \cdot d\right)}\\

\mathbf{elif}\;d \leq 2 \cdot 10^{-121}:\\
\;\;\;\;\frac{\mathsf{fma}\left(d \cdot a, \frac{-1}{c}, b\right)}{c}\\

\mathbf{elif}\;d \leq 5 \cdot 10^{+146}:\\
\;\;\;\;\mathsf{fma}\left(-a, \frac{d}{t\_0}, \frac{b \cdot c}{t\_0}\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if d < -4.1999999999999998e126 or 4.9999999999999999e146 < d

    1. Initial program 32.3%

      \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
    2. Add Preprocessing
    3. Taylor expanded in c around 0

      \[\leadsto \color{blue}{-1 \cdot \frac{a}{d} + \frac{b \cdot c}{{d}^{2}}} \]
    4. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} + -1 \cdot \frac{a}{d}} \]
      2. mul-1-negN/A

        \[\leadsto \frac{b \cdot c}{{d}^{2}} + \color{blue}{\left(\mathsf{neg}\left(\frac{a}{d}\right)\right)} \]
      3. unsub-negN/A

        \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} - \frac{a}{d}} \]
      4. unpow2N/A

        \[\leadsto \frac{b \cdot c}{\color{blue}{d \cdot d}} - \frac{a}{d} \]
      5. associate-/r*N/A

        \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d}}{d}} - \frac{a}{d} \]
      6. div-subN/A

        \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
      7. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
      8. sub-negN/A

        \[\leadsto \frac{\color{blue}{\frac{b \cdot c}{d} + \left(\mathsf{neg}\left(a\right)\right)}}{d} \]
      9. *-commutativeN/A

        \[\leadsto \frac{\frac{\color{blue}{c \cdot b}}{d} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
      10. associate-/l*N/A

        \[\leadsto \frac{\color{blue}{c \cdot \frac{b}{d}} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
      11. mul-1-negN/A

        \[\leadsto \frac{c \cdot \frac{b}{d} + \color{blue}{-1 \cdot a}}{d} \]
      12. lower-fma.f64N/A

        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(c, \frac{b}{d}, -1 \cdot a\right)}}{d} \]
      13. lower-/.f64N/A

        \[\leadsto \frac{\mathsf{fma}\left(c, \color{blue}{\frac{b}{d}}, -1 \cdot a\right)}{d} \]
      14. mul-1-negN/A

        \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{\mathsf{neg}\left(a\right)}\right)}{d} \]
      15. lower-neg.f6492.2

        \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{-a}\right)}{d} \]
    5. Applied rewrites92.2%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}} \]
    6. Step-by-step derivation
      1. Applied rewrites92.2%

        \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}} \]

      if -4.1999999999999998e126 < d < -2.32e-73

      1. Initial program 90.4%

        \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift-+.f64N/A

          \[\leadsto \frac{b \cdot c - a \cdot d}{\color{blue}{c \cdot c + d \cdot d}} \]
        2. lift-*.f64N/A

          \[\leadsto \frac{b \cdot c - a \cdot d}{\color{blue}{c \cdot c} + d \cdot d} \]
        3. lower-fma.f6490.4

          \[\leadsto \frac{b \cdot c - a \cdot d}{\color{blue}{\mathsf{fma}\left(c, c, d \cdot d\right)}} \]
      4. Applied rewrites90.4%

        \[\leadsto \frac{b \cdot c - a \cdot d}{\color{blue}{\mathsf{fma}\left(c, c, d \cdot d\right)}} \]

      if -2.32e-73 < d < 2e-121

      1. Initial program 69.7%

        \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
      2. Add Preprocessing
      3. Taylor expanded in c around inf

        \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
      4. Step-by-step derivation
        1. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
        2. mul-1-negN/A

          \[\leadsto \frac{b + \color{blue}{\left(\mathsf{neg}\left(\frac{a \cdot d}{c}\right)\right)}}{c} \]
        3. unsub-negN/A

          \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
        4. lower--.f64N/A

          \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
        5. lower-/.f64N/A

          \[\leadsto \frac{b - \color{blue}{\frac{a \cdot d}{c}}}{c} \]
        6. *-commutativeN/A

          \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
        7. lower-*.f6495.2

          \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
      5. Applied rewrites95.2%

        \[\leadsto \color{blue}{\frac{b - \frac{d \cdot a}{c}}{c}} \]
      6. Step-by-step derivation
        1. Applied rewrites95.2%

          \[\leadsto \frac{\mathsf{fma}\left(a \cdot d, \frac{-1}{c}, b\right)}{c} \]

        if 2e-121 < d < 4.9999999999999999e146

        1. Initial program 74.7%

          \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. lift-/.f64N/A

            \[\leadsto \color{blue}{\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d}} \]
          2. lift--.f64N/A

            \[\leadsto \frac{\color{blue}{b \cdot c - a \cdot d}}{c \cdot c + d \cdot d} \]
          3. div-subN/A

            \[\leadsto \color{blue}{\frac{b \cdot c}{c \cdot c + d \cdot d} - \frac{a \cdot d}{c \cdot c + d \cdot d}} \]
          4. sub-negN/A

            \[\leadsto \color{blue}{\frac{b \cdot c}{c \cdot c + d \cdot d} + \left(\mathsf{neg}\left(\frac{a \cdot d}{c \cdot c + d \cdot d}\right)\right)} \]
          5. +-commutativeN/A

            \[\leadsto \color{blue}{\left(\mathsf{neg}\left(\frac{a \cdot d}{c \cdot c + d \cdot d}\right)\right) + \frac{b \cdot c}{c \cdot c + d \cdot d}} \]
          6. lift-*.f64N/A

            \[\leadsto \left(\mathsf{neg}\left(\frac{\color{blue}{a \cdot d}}{c \cdot c + d \cdot d}\right)\right) + \frac{b \cdot c}{c \cdot c + d \cdot d} \]
          7. associate-/l*N/A

            \[\leadsto \left(\mathsf{neg}\left(\color{blue}{a \cdot \frac{d}{c \cdot c + d \cdot d}}\right)\right) + \frac{b \cdot c}{c \cdot c + d \cdot d} \]
          8. distribute-lft-neg-inN/A

            \[\leadsto \color{blue}{\left(\mathsf{neg}\left(a\right)\right) \cdot \frac{d}{c \cdot c + d \cdot d}} + \frac{b \cdot c}{c \cdot c + d \cdot d} \]
          9. lower-fma.f64N/A

            \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(a\right), \frac{d}{c \cdot c + d \cdot d}, \frac{b \cdot c}{c \cdot c + d \cdot d}\right)} \]
          10. lower-neg.f64N/A

            \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{neg}\left(a\right)}, \frac{d}{c \cdot c + d \cdot d}, \frac{b \cdot c}{c \cdot c + d \cdot d}\right) \]
          11. lower-/.f64N/A

            \[\leadsto \mathsf{fma}\left(\mathsf{neg}\left(a\right), \color{blue}{\frac{d}{c \cdot c + d \cdot d}}, \frac{b \cdot c}{c \cdot c + d \cdot d}\right) \]
          12. lift-+.f64N/A

            \[\leadsto \mathsf{fma}\left(\mathsf{neg}\left(a\right), \frac{d}{\color{blue}{c \cdot c + d \cdot d}}, \frac{b \cdot c}{c \cdot c + d \cdot d}\right) \]
          13. +-commutativeN/A

            \[\leadsto \mathsf{fma}\left(\mathsf{neg}\left(a\right), \frac{d}{\color{blue}{d \cdot d + c \cdot c}}, \frac{b \cdot c}{c \cdot c + d \cdot d}\right) \]
          14. lift-*.f64N/A

            \[\leadsto \mathsf{fma}\left(\mathsf{neg}\left(a\right), \frac{d}{\color{blue}{d \cdot d} + c \cdot c}, \frac{b \cdot c}{c \cdot c + d \cdot d}\right) \]
          15. lower-fma.f64N/A

            \[\leadsto \mathsf{fma}\left(\mathsf{neg}\left(a\right), \frac{d}{\color{blue}{\mathsf{fma}\left(d, d, c \cdot c\right)}}, \frac{b \cdot c}{c \cdot c + d \cdot d}\right) \]
          16. lower-/.f6482.3

            \[\leadsto \mathsf{fma}\left(-a, \frac{d}{\mathsf{fma}\left(d, d, c \cdot c\right)}, \color{blue}{\frac{b \cdot c}{c \cdot c + d \cdot d}}\right) \]
        4. Applied rewrites82.3%

          \[\leadsto \color{blue}{\mathsf{fma}\left(-a, \frac{d}{\mathsf{fma}\left(d, d, c \cdot c\right)}, \frac{c \cdot b}{\mathsf{fma}\left(d, d, c \cdot c\right)}\right)} \]
      7. Recombined 4 regimes into one program.
      8. Final simplification91.1%

        \[\leadsto \begin{array}{l} \mathbf{if}\;d \leq -4.2 \cdot 10^{+126}:\\ \;\;\;\;\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\ \mathbf{elif}\;d \leq -2.32 \cdot 10^{-73}:\\ \;\;\;\;\frac{b \cdot c - d \cdot a}{\mathsf{fma}\left(c, c, d \cdot d\right)}\\ \mathbf{elif}\;d \leq 2 \cdot 10^{-121}:\\ \;\;\;\;\frac{\mathsf{fma}\left(d \cdot a, \frac{-1}{c}, b\right)}{c}\\ \mathbf{elif}\;d \leq 5 \cdot 10^{+146}:\\ \;\;\;\;\mathsf{fma}\left(-a, \frac{d}{\mathsf{fma}\left(d, d, c \cdot c\right)}, \frac{b \cdot c}{\mathsf{fma}\left(d, d, c \cdot c\right)}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\ \end{array} \]
      9. Add Preprocessing

      Alternative 2: 82.2% accurate, 0.6× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{b \cdot c - d \cdot a}{\mathsf{fma}\left(c, c, d \cdot d\right)}\\ t_1 := \frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\ \mathbf{if}\;d \leq -4.2 \cdot 10^{+126}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;d \leq -2.32 \cdot 10^{-73}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;d \leq 2 \cdot 10^{-121}:\\ \;\;\;\;\frac{\mathsf{fma}\left(d \cdot a, \frac{-1}{c}, b\right)}{c}\\ \mathbf{elif}\;d \leq 3.8 \cdot 10^{+38}:\\ \;\;\;\;t\_0\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \end{array} \]
      (FPCore (a b c d)
       :precision binary64
       (let* ((t_0 (/ (- (* b c) (* d a)) (fma c c (* d d))))
              (t_1 (/ (fma b (/ c d) (- a)) d)))
         (if (<= d -4.2e+126)
           t_1
           (if (<= d -2.32e-73)
             t_0
             (if (<= d 2e-121)
               (/ (fma (* d a) (/ -1.0 c) b) c)
               (if (<= d 3.8e+38) t_0 t_1))))))
      double code(double a, double b, double c, double d) {
      	double t_0 = ((b * c) - (d * a)) / fma(c, c, (d * d));
      	double t_1 = fma(b, (c / d), -a) / d;
      	double tmp;
      	if (d <= -4.2e+126) {
      		tmp = t_1;
      	} else if (d <= -2.32e-73) {
      		tmp = t_0;
      	} else if (d <= 2e-121) {
      		tmp = fma((d * a), (-1.0 / c), b) / c;
      	} else if (d <= 3.8e+38) {
      		tmp = t_0;
      	} else {
      		tmp = t_1;
      	}
      	return tmp;
      }
      
      function code(a, b, c, d)
      	t_0 = Float64(Float64(Float64(b * c) - Float64(d * a)) / fma(c, c, Float64(d * d)))
      	t_1 = Float64(fma(b, Float64(c / d), Float64(-a)) / d)
      	tmp = 0.0
      	if (d <= -4.2e+126)
      		tmp = t_1;
      	elseif (d <= -2.32e-73)
      		tmp = t_0;
      	elseif (d <= 2e-121)
      		tmp = Float64(fma(Float64(d * a), Float64(-1.0 / c), b) / c);
      	elseif (d <= 3.8e+38)
      		tmp = t_0;
      	else
      		tmp = t_1;
      	end
      	return tmp
      end
      
      code[a_, b_, c_, d_] := Block[{t$95$0 = N[(N[(N[(b * c), $MachinePrecision] - N[(d * a), $MachinePrecision]), $MachinePrecision] / N[(c * c + N[(d * d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(b * N[(c / d), $MachinePrecision] + (-a)), $MachinePrecision] / d), $MachinePrecision]}, If[LessEqual[d, -4.2e+126], t$95$1, If[LessEqual[d, -2.32e-73], t$95$0, If[LessEqual[d, 2e-121], N[(N[(N[(d * a), $MachinePrecision] * N[(-1.0 / c), $MachinePrecision] + b), $MachinePrecision] / c), $MachinePrecision], If[LessEqual[d, 3.8e+38], t$95$0, t$95$1]]]]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \frac{b \cdot c - d \cdot a}{\mathsf{fma}\left(c, c, d \cdot d\right)}\\
      t_1 := \frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\
      \mathbf{if}\;d \leq -4.2 \cdot 10^{+126}:\\
      \;\;\;\;t\_1\\
      
      \mathbf{elif}\;d \leq -2.32 \cdot 10^{-73}:\\
      \;\;\;\;t\_0\\
      
      \mathbf{elif}\;d \leq 2 \cdot 10^{-121}:\\
      \;\;\;\;\frac{\mathsf{fma}\left(d \cdot a, \frac{-1}{c}, b\right)}{c}\\
      
      \mathbf{elif}\;d \leq 3.8 \cdot 10^{+38}:\\
      \;\;\;\;t\_0\\
      
      \mathbf{else}:\\
      \;\;\;\;t\_1\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if d < -4.1999999999999998e126 or 3.7999999999999998e38 < d

        1. Initial program 41.2%

          \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
        2. Add Preprocessing
        3. Taylor expanded in c around 0

          \[\leadsto \color{blue}{-1 \cdot \frac{a}{d} + \frac{b \cdot c}{{d}^{2}}} \]
        4. Step-by-step derivation
          1. +-commutativeN/A

            \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} + -1 \cdot \frac{a}{d}} \]
          2. mul-1-negN/A

            \[\leadsto \frac{b \cdot c}{{d}^{2}} + \color{blue}{\left(\mathsf{neg}\left(\frac{a}{d}\right)\right)} \]
          3. unsub-negN/A

            \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} - \frac{a}{d}} \]
          4. unpow2N/A

            \[\leadsto \frac{b \cdot c}{\color{blue}{d \cdot d}} - \frac{a}{d} \]
          5. associate-/r*N/A

            \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d}}{d}} - \frac{a}{d} \]
          6. div-subN/A

            \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
          7. lower-/.f64N/A

            \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
          8. sub-negN/A

            \[\leadsto \frac{\color{blue}{\frac{b \cdot c}{d} + \left(\mathsf{neg}\left(a\right)\right)}}{d} \]
          9. *-commutativeN/A

            \[\leadsto \frac{\frac{\color{blue}{c \cdot b}}{d} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
          10. associate-/l*N/A

            \[\leadsto \frac{\color{blue}{c \cdot \frac{b}{d}} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
          11. mul-1-negN/A

            \[\leadsto \frac{c \cdot \frac{b}{d} + \color{blue}{-1 \cdot a}}{d} \]
          12. lower-fma.f64N/A

            \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(c, \frac{b}{d}, -1 \cdot a\right)}}{d} \]
          13. lower-/.f64N/A

            \[\leadsto \frac{\mathsf{fma}\left(c, \color{blue}{\frac{b}{d}}, -1 \cdot a\right)}{d} \]
          14. mul-1-negN/A

            \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{\mathsf{neg}\left(a\right)}\right)}{d} \]
          15. lower-neg.f6488.8

            \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{-a}\right)}{d} \]
        5. Applied rewrites88.8%

          \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}} \]
        6. Step-by-step derivation
          1. Applied rewrites88.8%

            \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}} \]

          if -4.1999999999999998e126 < d < -2.32e-73 or 2e-121 < d < 3.7999999999999998e38

          1. Initial program 85.8%

            \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-+.f64N/A

              \[\leadsto \frac{b \cdot c - a \cdot d}{\color{blue}{c \cdot c + d \cdot d}} \]
            2. lift-*.f64N/A

              \[\leadsto \frac{b \cdot c - a \cdot d}{\color{blue}{c \cdot c} + d \cdot d} \]
            3. lower-fma.f6485.9

              \[\leadsto \frac{b \cdot c - a \cdot d}{\color{blue}{\mathsf{fma}\left(c, c, d \cdot d\right)}} \]
          4. Applied rewrites85.9%

            \[\leadsto \frac{b \cdot c - a \cdot d}{\color{blue}{\mathsf{fma}\left(c, c, d \cdot d\right)}} \]

          if -2.32e-73 < d < 2e-121

          1. Initial program 69.7%

            \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
          2. Add Preprocessing
          3. Taylor expanded in c around inf

            \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
          4. Step-by-step derivation
            1. lower-/.f64N/A

              \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
            2. mul-1-negN/A

              \[\leadsto \frac{b + \color{blue}{\left(\mathsf{neg}\left(\frac{a \cdot d}{c}\right)\right)}}{c} \]
            3. unsub-negN/A

              \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
            4. lower--.f64N/A

              \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
            5. lower-/.f64N/A

              \[\leadsto \frac{b - \color{blue}{\frac{a \cdot d}{c}}}{c} \]
            6. *-commutativeN/A

              \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
            7. lower-*.f6495.2

              \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
          5. Applied rewrites95.2%

            \[\leadsto \color{blue}{\frac{b - \frac{d \cdot a}{c}}{c}} \]
          6. Step-by-step derivation
            1. Applied rewrites95.2%

              \[\leadsto \frac{\mathsf{fma}\left(a \cdot d, \frac{-1}{c}, b\right)}{c} \]
          7. Recombined 3 regimes into one program.
          8. Final simplification90.4%

            \[\leadsto \begin{array}{l} \mathbf{if}\;d \leq -4.2 \cdot 10^{+126}:\\ \;\;\;\;\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\ \mathbf{elif}\;d \leq -2.32 \cdot 10^{-73}:\\ \;\;\;\;\frac{b \cdot c - d \cdot a}{\mathsf{fma}\left(c, c, d \cdot d\right)}\\ \mathbf{elif}\;d \leq 2 \cdot 10^{-121}:\\ \;\;\;\;\frac{\mathsf{fma}\left(d \cdot a, \frac{-1}{c}, b\right)}{c}\\ \mathbf{elif}\;d \leq 3.8 \cdot 10^{+38}:\\ \;\;\;\;\frac{b \cdot c - d \cdot a}{\mathsf{fma}\left(c, c, d \cdot d\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\ \end{array} \]
          9. Add Preprocessing

          Alternative 3: 76.0% accurate, 0.8× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;d \leq -65000000000:\\ \;\;\;\;\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}\\ \mathbf{elif}\;d \leq 3.1 \cdot 10^{-116}:\\ \;\;\;\;\frac{\mathsf{fma}\left(d \cdot a, \frac{-1}{c}, b\right)}{c}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\ \end{array} \end{array} \]
          (FPCore (a b c d)
           :precision binary64
           (if (<= d -65000000000.0)
             (/ (fma c (/ b d) (- a)) d)
             (if (<= d 3.1e-116)
               (/ (fma (* d a) (/ -1.0 c) b) c)
               (/ (fma b (/ c d) (- a)) d))))
          double code(double a, double b, double c, double d) {
          	double tmp;
          	if (d <= -65000000000.0) {
          		tmp = fma(c, (b / d), -a) / d;
          	} else if (d <= 3.1e-116) {
          		tmp = fma((d * a), (-1.0 / c), b) / c;
          	} else {
          		tmp = fma(b, (c / d), -a) / d;
          	}
          	return tmp;
          }
          
          function code(a, b, c, d)
          	tmp = 0.0
          	if (d <= -65000000000.0)
          		tmp = Float64(fma(c, Float64(b / d), Float64(-a)) / d);
          	elseif (d <= 3.1e-116)
          		tmp = Float64(fma(Float64(d * a), Float64(-1.0 / c), b) / c);
          	else
          		tmp = Float64(fma(b, Float64(c / d), Float64(-a)) / d);
          	end
          	return tmp
          end
          
          code[a_, b_, c_, d_] := If[LessEqual[d, -65000000000.0], N[(N[(c * N[(b / d), $MachinePrecision] + (-a)), $MachinePrecision] / d), $MachinePrecision], If[LessEqual[d, 3.1e-116], N[(N[(N[(d * a), $MachinePrecision] * N[(-1.0 / c), $MachinePrecision] + b), $MachinePrecision] / c), $MachinePrecision], N[(N[(b * N[(c / d), $MachinePrecision] + (-a)), $MachinePrecision] / d), $MachinePrecision]]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;d \leq -65000000000:\\
          \;\;\;\;\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}\\
          
          \mathbf{elif}\;d \leq 3.1 \cdot 10^{-116}:\\
          \;\;\;\;\frac{\mathsf{fma}\left(d \cdot a, \frac{-1}{c}, b\right)}{c}\\
          
          \mathbf{else}:\\
          \;\;\;\;\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 3 regimes
          2. if d < -6.5e10

            1. Initial program 57.6%

              \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
            2. Add Preprocessing
            3. Taylor expanded in c around 0

              \[\leadsto \color{blue}{-1 \cdot \frac{a}{d} + \frac{b \cdot c}{{d}^{2}}} \]
            4. Step-by-step derivation
              1. +-commutativeN/A

                \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} + -1 \cdot \frac{a}{d}} \]
              2. mul-1-negN/A

                \[\leadsto \frac{b \cdot c}{{d}^{2}} + \color{blue}{\left(\mathsf{neg}\left(\frac{a}{d}\right)\right)} \]
              3. unsub-negN/A

                \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} - \frac{a}{d}} \]
              4. unpow2N/A

                \[\leadsto \frac{b \cdot c}{\color{blue}{d \cdot d}} - \frac{a}{d} \]
              5. associate-/r*N/A

                \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d}}{d}} - \frac{a}{d} \]
              6. div-subN/A

                \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
              7. lower-/.f64N/A

                \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
              8. sub-negN/A

                \[\leadsto \frac{\color{blue}{\frac{b \cdot c}{d} + \left(\mathsf{neg}\left(a\right)\right)}}{d} \]
              9. *-commutativeN/A

                \[\leadsto \frac{\frac{\color{blue}{c \cdot b}}{d} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
              10. associate-/l*N/A

                \[\leadsto \frac{\color{blue}{c \cdot \frac{b}{d}} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
              11. mul-1-negN/A

                \[\leadsto \frac{c \cdot \frac{b}{d} + \color{blue}{-1 \cdot a}}{d} \]
              12. lower-fma.f64N/A

                \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(c, \frac{b}{d}, -1 \cdot a\right)}}{d} \]
              13. lower-/.f64N/A

                \[\leadsto \frac{\mathsf{fma}\left(c, \color{blue}{\frac{b}{d}}, -1 \cdot a\right)}{d} \]
              14. mul-1-negN/A

                \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{\mathsf{neg}\left(a\right)}\right)}{d} \]
              15. lower-neg.f6481.7

                \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{-a}\right)}{d} \]
            5. Applied rewrites81.7%

              \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}} \]

            if -6.5e10 < d < 3.10000000000000018e-116

            1. Initial program 72.8%

              \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
            2. Add Preprocessing
            3. Taylor expanded in c around inf

              \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
            4. Step-by-step derivation
              1. lower-/.f64N/A

                \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
              2. mul-1-negN/A

                \[\leadsto \frac{b + \color{blue}{\left(\mathsf{neg}\left(\frac{a \cdot d}{c}\right)\right)}}{c} \]
              3. unsub-negN/A

                \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
              4. lower--.f64N/A

                \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
              5. lower-/.f64N/A

                \[\leadsto \frac{b - \color{blue}{\frac{a \cdot d}{c}}}{c} \]
              6. *-commutativeN/A

                \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
              7. lower-*.f6490.1

                \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
            5. Applied rewrites90.1%

              \[\leadsto \color{blue}{\frac{b - \frac{d \cdot a}{c}}{c}} \]
            6. Step-by-step derivation
              1. Applied rewrites90.1%

                \[\leadsto \frac{\mathsf{fma}\left(a \cdot d, \frac{-1}{c}, b\right)}{c} \]

              if 3.10000000000000018e-116 < d

              1. Initial program 56.7%

                \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
              2. Add Preprocessing
              3. Taylor expanded in c around 0

                \[\leadsto \color{blue}{-1 \cdot \frac{a}{d} + \frac{b \cdot c}{{d}^{2}}} \]
              4. Step-by-step derivation
                1. +-commutativeN/A

                  \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} + -1 \cdot \frac{a}{d}} \]
                2. mul-1-negN/A

                  \[\leadsto \frac{b \cdot c}{{d}^{2}} + \color{blue}{\left(\mathsf{neg}\left(\frac{a}{d}\right)\right)} \]
                3. unsub-negN/A

                  \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} - \frac{a}{d}} \]
                4. unpow2N/A

                  \[\leadsto \frac{b \cdot c}{\color{blue}{d \cdot d}} - \frac{a}{d} \]
                5. associate-/r*N/A

                  \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d}}{d}} - \frac{a}{d} \]
                6. div-subN/A

                  \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
                7. lower-/.f64N/A

                  \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
                8. sub-negN/A

                  \[\leadsto \frac{\color{blue}{\frac{b \cdot c}{d} + \left(\mathsf{neg}\left(a\right)\right)}}{d} \]
                9. *-commutativeN/A

                  \[\leadsto \frac{\frac{\color{blue}{c \cdot b}}{d} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
                10. associate-/l*N/A

                  \[\leadsto \frac{\color{blue}{c \cdot \frac{b}{d}} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
                11. mul-1-negN/A

                  \[\leadsto \frac{c \cdot \frac{b}{d} + \color{blue}{-1 \cdot a}}{d} \]
                12. lower-fma.f64N/A

                  \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(c, \frac{b}{d}, -1 \cdot a\right)}}{d} \]
                13. lower-/.f64N/A

                  \[\leadsto \frac{\mathsf{fma}\left(c, \color{blue}{\frac{b}{d}}, -1 \cdot a\right)}{d} \]
                14. mul-1-negN/A

                  \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{\mathsf{neg}\left(a\right)}\right)}{d} \]
                15. lower-neg.f6480.3

                  \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{-a}\right)}{d} \]
              5. Applied rewrites80.3%

                \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}} \]
              6. Step-by-step derivation
                1. Applied rewrites81.3%

                  \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}} \]
              7. Recombined 3 regimes into one program.
              8. Final simplification85.3%

                \[\leadsto \begin{array}{l} \mathbf{if}\;d \leq -65000000000:\\ \;\;\;\;\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}\\ \mathbf{elif}\;d \leq 3.1 \cdot 10^{-116}:\\ \;\;\;\;\frac{\mathsf{fma}\left(d \cdot a, \frac{-1}{c}, b\right)}{c}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\ \end{array} \]
              9. Add Preprocessing

              Alternative 4: 76.0% accurate, 0.9× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;d \leq -65000000000:\\ \;\;\;\;\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}\\ \mathbf{elif}\;d \leq 3.1 \cdot 10^{-116}:\\ \;\;\;\;\frac{b - \frac{d \cdot a}{c}}{c}\\ \mathbf{else}:\\ \;\;\;\;\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\ \end{array} \end{array} \]
              (FPCore (a b c d)
               :precision binary64
               (if (<= d -65000000000.0)
                 (/ (fma c (/ b d) (- a)) d)
                 (if (<= d 3.1e-116) (/ (- b (/ (* d a) c)) c) (/ (fma b (/ c d) (- a)) d))))
              double code(double a, double b, double c, double d) {
              	double tmp;
              	if (d <= -65000000000.0) {
              		tmp = fma(c, (b / d), -a) / d;
              	} else if (d <= 3.1e-116) {
              		tmp = (b - ((d * a) / c)) / c;
              	} else {
              		tmp = fma(b, (c / d), -a) / d;
              	}
              	return tmp;
              }
              
              function code(a, b, c, d)
              	tmp = 0.0
              	if (d <= -65000000000.0)
              		tmp = Float64(fma(c, Float64(b / d), Float64(-a)) / d);
              	elseif (d <= 3.1e-116)
              		tmp = Float64(Float64(b - Float64(Float64(d * a) / c)) / c);
              	else
              		tmp = Float64(fma(b, Float64(c / d), Float64(-a)) / d);
              	end
              	return tmp
              end
              
              code[a_, b_, c_, d_] := If[LessEqual[d, -65000000000.0], N[(N[(c * N[(b / d), $MachinePrecision] + (-a)), $MachinePrecision] / d), $MachinePrecision], If[LessEqual[d, 3.1e-116], N[(N[(b - N[(N[(d * a), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision], N[(N[(b * N[(c / d), $MachinePrecision] + (-a)), $MachinePrecision] / d), $MachinePrecision]]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;d \leq -65000000000:\\
              \;\;\;\;\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}\\
              
              \mathbf{elif}\;d \leq 3.1 \cdot 10^{-116}:\\
              \;\;\;\;\frac{b - \frac{d \cdot a}{c}}{c}\\
              
              \mathbf{else}:\\
              \;\;\;\;\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 3 regimes
              2. if d < -6.5e10

                1. Initial program 57.6%

                  \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                2. Add Preprocessing
                3. Taylor expanded in c around 0

                  \[\leadsto \color{blue}{-1 \cdot \frac{a}{d} + \frac{b \cdot c}{{d}^{2}}} \]
                4. Step-by-step derivation
                  1. +-commutativeN/A

                    \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} + -1 \cdot \frac{a}{d}} \]
                  2. mul-1-negN/A

                    \[\leadsto \frac{b \cdot c}{{d}^{2}} + \color{blue}{\left(\mathsf{neg}\left(\frac{a}{d}\right)\right)} \]
                  3. unsub-negN/A

                    \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} - \frac{a}{d}} \]
                  4. unpow2N/A

                    \[\leadsto \frac{b \cdot c}{\color{blue}{d \cdot d}} - \frac{a}{d} \]
                  5. associate-/r*N/A

                    \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d}}{d}} - \frac{a}{d} \]
                  6. div-subN/A

                    \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
                  7. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
                  8. sub-negN/A

                    \[\leadsto \frac{\color{blue}{\frac{b \cdot c}{d} + \left(\mathsf{neg}\left(a\right)\right)}}{d} \]
                  9. *-commutativeN/A

                    \[\leadsto \frac{\frac{\color{blue}{c \cdot b}}{d} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
                  10. associate-/l*N/A

                    \[\leadsto \frac{\color{blue}{c \cdot \frac{b}{d}} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
                  11. mul-1-negN/A

                    \[\leadsto \frac{c \cdot \frac{b}{d} + \color{blue}{-1 \cdot a}}{d} \]
                  12. lower-fma.f64N/A

                    \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(c, \frac{b}{d}, -1 \cdot a\right)}}{d} \]
                  13. lower-/.f64N/A

                    \[\leadsto \frac{\mathsf{fma}\left(c, \color{blue}{\frac{b}{d}}, -1 \cdot a\right)}{d} \]
                  14. mul-1-negN/A

                    \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{\mathsf{neg}\left(a\right)}\right)}{d} \]
                  15. lower-neg.f6481.7

                    \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{-a}\right)}{d} \]
                5. Applied rewrites81.7%

                  \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}} \]

                if -6.5e10 < d < 3.10000000000000018e-116

                1. Initial program 72.8%

                  \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                2. Add Preprocessing
                3. Taylor expanded in c around inf

                  \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
                4. Step-by-step derivation
                  1. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
                  2. mul-1-negN/A

                    \[\leadsto \frac{b + \color{blue}{\left(\mathsf{neg}\left(\frac{a \cdot d}{c}\right)\right)}}{c} \]
                  3. unsub-negN/A

                    \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
                  4. lower--.f64N/A

                    \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
                  5. lower-/.f64N/A

                    \[\leadsto \frac{b - \color{blue}{\frac{a \cdot d}{c}}}{c} \]
                  6. *-commutativeN/A

                    \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
                  7. lower-*.f6490.1

                    \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
                5. Applied rewrites90.1%

                  \[\leadsto \color{blue}{\frac{b - \frac{d \cdot a}{c}}{c}} \]

                if 3.10000000000000018e-116 < d

                1. Initial program 56.7%

                  \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                2. Add Preprocessing
                3. Taylor expanded in c around 0

                  \[\leadsto \color{blue}{-1 \cdot \frac{a}{d} + \frac{b \cdot c}{{d}^{2}}} \]
                4. Step-by-step derivation
                  1. +-commutativeN/A

                    \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} + -1 \cdot \frac{a}{d}} \]
                  2. mul-1-negN/A

                    \[\leadsto \frac{b \cdot c}{{d}^{2}} + \color{blue}{\left(\mathsf{neg}\left(\frac{a}{d}\right)\right)} \]
                  3. unsub-negN/A

                    \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} - \frac{a}{d}} \]
                  4. unpow2N/A

                    \[\leadsto \frac{b \cdot c}{\color{blue}{d \cdot d}} - \frac{a}{d} \]
                  5. associate-/r*N/A

                    \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d}}{d}} - \frac{a}{d} \]
                  6. div-subN/A

                    \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
                  7. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
                  8. sub-negN/A

                    \[\leadsto \frac{\color{blue}{\frac{b \cdot c}{d} + \left(\mathsf{neg}\left(a\right)\right)}}{d} \]
                  9. *-commutativeN/A

                    \[\leadsto \frac{\frac{\color{blue}{c \cdot b}}{d} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
                  10. associate-/l*N/A

                    \[\leadsto \frac{\color{blue}{c \cdot \frac{b}{d}} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
                  11. mul-1-negN/A

                    \[\leadsto \frac{c \cdot \frac{b}{d} + \color{blue}{-1 \cdot a}}{d} \]
                  12. lower-fma.f64N/A

                    \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(c, \frac{b}{d}, -1 \cdot a\right)}}{d} \]
                  13. lower-/.f64N/A

                    \[\leadsto \frac{\mathsf{fma}\left(c, \color{blue}{\frac{b}{d}}, -1 \cdot a\right)}{d} \]
                  14. mul-1-negN/A

                    \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{\mathsf{neg}\left(a\right)}\right)}{d} \]
                  15. lower-neg.f6480.3

                    \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{-a}\right)}{d} \]
                5. Applied rewrites80.3%

                  \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}} \]
                6. Step-by-step derivation
                  1. Applied rewrites81.3%

                    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}} \]
                7. Recombined 3 regimes into one program.
                8. Add Preprocessing

                Alternative 5: 75.8% accurate, 0.9× speedup?

                \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\ \mathbf{if}\;d \leq -65000000000:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;d \leq 3.1 \cdot 10^{-116}:\\ \;\;\;\;\frac{b - \frac{d \cdot a}{c}}{c}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
                (FPCore (a b c d)
                 :precision binary64
                 (let* ((t_0 (/ (fma b (/ c d) (- a)) d)))
                   (if (<= d -65000000000.0)
                     t_0
                     (if (<= d 3.1e-116) (/ (- b (/ (* d a) c)) c) t_0))))
                double code(double a, double b, double c, double d) {
                	double t_0 = fma(b, (c / d), -a) / d;
                	double tmp;
                	if (d <= -65000000000.0) {
                		tmp = t_0;
                	} else if (d <= 3.1e-116) {
                		tmp = (b - ((d * a) / c)) / c;
                	} else {
                		tmp = t_0;
                	}
                	return tmp;
                }
                
                function code(a, b, c, d)
                	t_0 = Float64(fma(b, Float64(c / d), Float64(-a)) / d)
                	tmp = 0.0
                	if (d <= -65000000000.0)
                		tmp = t_0;
                	elseif (d <= 3.1e-116)
                		tmp = Float64(Float64(b - Float64(Float64(d * a) / c)) / c);
                	else
                		tmp = t_0;
                	end
                	return tmp
                end
                
                code[a_, b_, c_, d_] := Block[{t$95$0 = N[(N[(b * N[(c / d), $MachinePrecision] + (-a)), $MachinePrecision] / d), $MachinePrecision]}, If[LessEqual[d, -65000000000.0], t$95$0, If[LessEqual[d, 3.1e-116], N[(N[(b - N[(N[(d * a), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision], t$95$0]]]
                
                \begin{array}{l}
                
                \\
                \begin{array}{l}
                t_0 := \frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}\\
                \mathbf{if}\;d \leq -65000000000:\\
                \;\;\;\;t\_0\\
                
                \mathbf{elif}\;d \leq 3.1 \cdot 10^{-116}:\\
                \;\;\;\;\frac{b - \frac{d \cdot a}{c}}{c}\\
                
                \mathbf{else}:\\
                \;\;\;\;t\_0\\
                
                
                \end{array}
                \end{array}
                
                Derivation
                1. Split input into 2 regimes
                2. if d < -6.5e10 or 3.10000000000000018e-116 < d

                  1. Initial program 57.1%

                    \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                  2. Add Preprocessing
                  3. Taylor expanded in c around 0

                    \[\leadsto \color{blue}{-1 \cdot \frac{a}{d} + \frac{b \cdot c}{{d}^{2}}} \]
                  4. Step-by-step derivation
                    1. +-commutativeN/A

                      \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} + -1 \cdot \frac{a}{d}} \]
                    2. mul-1-negN/A

                      \[\leadsto \frac{b \cdot c}{{d}^{2}} + \color{blue}{\left(\mathsf{neg}\left(\frac{a}{d}\right)\right)} \]
                    3. unsub-negN/A

                      \[\leadsto \color{blue}{\frac{b \cdot c}{{d}^{2}} - \frac{a}{d}} \]
                    4. unpow2N/A

                      \[\leadsto \frac{b \cdot c}{\color{blue}{d \cdot d}} - \frac{a}{d} \]
                    5. associate-/r*N/A

                      \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d}}{d}} - \frac{a}{d} \]
                    6. div-subN/A

                      \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
                    7. lower-/.f64N/A

                      \[\leadsto \color{blue}{\frac{\frac{b \cdot c}{d} - a}{d}} \]
                    8. sub-negN/A

                      \[\leadsto \frac{\color{blue}{\frac{b \cdot c}{d} + \left(\mathsf{neg}\left(a\right)\right)}}{d} \]
                    9. *-commutativeN/A

                      \[\leadsto \frac{\frac{\color{blue}{c \cdot b}}{d} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
                    10. associate-/l*N/A

                      \[\leadsto \frac{\color{blue}{c \cdot \frac{b}{d}} + \left(\mathsf{neg}\left(a\right)\right)}{d} \]
                    11. mul-1-negN/A

                      \[\leadsto \frac{c \cdot \frac{b}{d} + \color{blue}{-1 \cdot a}}{d} \]
                    12. lower-fma.f64N/A

                      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(c, \frac{b}{d}, -1 \cdot a\right)}}{d} \]
                    13. lower-/.f64N/A

                      \[\leadsto \frac{\mathsf{fma}\left(c, \color{blue}{\frac{b}{d}}, -1 \cdot a\right)}{d} \]
                    14. mul-1-negN/A

                      \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{\mathsf{neg}\left(a\right)}\right)}{d} \]
                    15. lower-neg.f6480.8

                      \[\leadsto \frac{\mathsf{fma}\left(c, \frac{b}{d}, \color{blue}{-a}\right)}{d} \]
                  5. Applied rewrites80.8%

                    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(c, \frac{b}{d}, -a\right)}{d}} \]
                  6. Step-by-step derivation
                    1. Applied rewrites81.5%

                      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(b, \frac{c}{d}, -a\right)}{d}} \]

                    if -6.5e10 < d < 3.10000000000000018e-116

                    1. Initial program 72.8%

                      \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                    2. Add Preprocessing
                    3. Taylor expanded in c around inf

                      \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
                    4. Step-by-step derivation
                      1. lower-/.f64N/A

                        \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
                      2. mul-1-negN/A

                        \[\leadsto \frac{b + \color{blue}{\left(\mathsf{neg}\left(\frac{a \cdot d}{c}\right)\right)}}{c} \]
                      3. unsub-negN/A

                        \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
                      4. lower--.f64N/A

                        \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
                      5. lower-/.f64N/A

                        \[\leadsto \frac{b - \color{blue}{\frac{a \cdot d}{c}}}{c} \]
                      6. *-commutativeN/A

                        \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
                      7. lower-*.f6490.1

                        \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
                    5. Applied rewrites90.1%

                      \[\leadsto \color{blue}{\frac{b - \frac{d \cdot a}{c}}{c}} \]
                  7. Recombined 2 regimes into one program.
                  8. Add Preprocessing

                  Alternative 6: 73.1% accurate, 0.9× speedup?

                  \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{a}{-d}\\ \mathbf{if}\;d \leq -65000000000:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;d \leq 8.5 \cdot 10^{+34}:\\ \;\;\;\;\frac{b - \frac{d \cdot a}{c}}{c}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
                  (FPCore (a b c d)
                   :precision binary64
                   (let* ((t_0 (/ a (- d))))
                     (if (<= d -65000000000.0)
                       t_0
                       (if (<= d 8.5e+34) (/ (- b (/ (* d a) c)) c) t_0))))
                  double code(double a, double b, double c, double d) {
                  	double t_0 = a / -d;
                  	double tmp;
                  	if (d <= -65000000000.0) {
                  		tmp = t_0;
                  	} else if (d <= 8.5e+34) {
                  		tmp = (b - ((d * a) / c)) / c;
                  	} else {
                  		tmp = t_0;
                  	}
                  	return tmp;
                  }
                  
                  real(8) function code(a, b, c, d)
                      real(8), intent (in) :: a
                      real(8), intent (in) :: b
                      real(8), intent (in) :: c
                      real(8), intent (in) :: d
                      real(8) :: t_0
                      real(8) :: tmp
                      t_0 = a / -d
                      if (d <= (-65000000000.0d0)) then
                          tmp = t_0
                      else if (d <= 8.5d+34) then
                          tmp = (b - ((d * a) / c)) / c
                      else
                          tmp = t_0
                      end if
                      code = tmp
                  end function
                  
                  public static double code(double a, double b, double c, double d) {
                  	double t_0 = a / -d;
                  	double tmp;
                  	if (d <= -65000000000.0) {
                  		tmp = t_0;
                  	} else if (d <= 8.5e+34) {
                  		tmp = (b - ((d * a) / c)) / c;
                  	} else {
                  		tmp = t_0;
                  	}
                  	return tmp;
                  }
                  
                  def code(a, b, c, d):
                  	t_0 = a / -d
                  	tmp = 0
                  	if d <= -65000000000.0:
                  		tmp = t_0
                  	elif d <= 8.5e+34:
                  		tmp = (b - ((d * a) / c)) / c
                  	else:
                  		tmp = t_0
                  	return tmp
                  
                  function code(a, b, c, d)
                  	t_0 = Float64(a / Float64(-d))
                  	tmp = 0.0
                  	if (d <= -65000000000.0)
                  		tmp = t_0;
                  	elseif (d <= 8.5e+34)
                  		tmp = Float64(Float64(b - Float64(Float64(d * a) / c)) / c);
                  	else
                  		tmp = t_0;
                  	end
                  	return tmp
                  end
                  
                  function tmp_2 = code(a, b, c, d)
                  	t_0 = a / -d;
                  	tmp = 0.0;
                  	if (d <= -65000000000.0)
                  		tmp = t_0;
                  	elseif (d <= 8.5e+34)
                  		tmp = (b - ((d * a) / c)) / c;
                  	else
                  		tmp = t_0;
                  	end
                  	tmp_2 = tmp;
                  end
                  
                  code[a_, b_, c_, d_] := Block[{t$95$0 = N[(a / (-d)), $MachinePrecision]}, If[LessEqual[d, -65000000000.0], t$95$0, If[LessEqual[d, 8.5e+34], N[(N[(b - N[(N[(d * a), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision], t$95$0]]]
                  
                  \begin{array}{l}
                  
                  \\
                  \begin{array}{l}
                  t_0 := \frac{a}{-d}\\
                  \mathbf{if}\;d \leq -65000000000:\\
                  \;\;\;\;t\_0\\
                  
                  \mathbf{elif}\;d \leq 8.5 \cdot 10^{+34}:\\
                  \;\;\;\;\frac{b - \frac{d \cdot a}{c}}{c}\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;t\_0\\
                  
                  
                  \end{array}
                  \end{array}
                  
                  Derivation
                  1. Split input into 2 regimes
                  2. if d < -6.5e10 or 8.5000000000000003e34 < d

                    1. Initial program 51.7%

                      \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                    2. Add Preprocessing
                    3. Taylor expanded in c around 0

                      \[\leadsto \color{blue}{-1 \cdot \frac{a}{d}} \]
                    4. Step-by-step derivation
                      1. mul-1-negN/A

                        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{a}{d}\right)} \]
                      2. distribute-neg-frac2N/A

                        \[\leadsto \color{blue}{\frac{a}{\mathsf{neg}\left(d\right)}} \]
                      3. mul-1-negN/A

                        \[\leadsto \frac{a}{\color{blue}{-1 \cdot d}} \]
                      4. lower-/.f64N/A

                        \[\leadsto \color{blue}{\frac{a}{-1 \cdot d}} \]
                      5. mul-1-negN/A

                        \[\leadsto \frac{a}{\color{blue}{\mathsf{neg}\left(d\right)}} \]
                      6. lower-neg.f6480.7

                        \[\leadsto \frac{a}{\color{blue}{-d}} \]
                    5. Applied rewrites80.7%

                      \[\leadsto \color{blue}{\frac{a}{-d}} \]

                    if -6.5e10 < d < 8.5000000000000003e34

                    1. Initial program 74.0%

                      \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                    2. Add Preprocessing
                    3. Taylor expanded in c around inf

                      \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
                    4. Step-by-step derivation
                      1. lower-/.f64N/A

                        \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
                      2. mul-1-negN/A

                        \[\leadsto \frac{b + \color{blue}{\left(\mathsf{neg}\left(\frac{a \cdot d}{c}\right)\right)}}{c} \]
                      3. unsub-negN/A

                        \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
                      4. lower--.f64N/A

                        \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
                      5. lower-/.f64N/A

                        \[\leadsto \frac{b - \color{blue}{\frac{a \cdot d}{c}}}{c} \]
                      6. *-commutativeN/A

                        \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
                      7. lower-*.f6482.6

                        \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
                    5. Applied rewrites82.6%

                      \[\leadsto \color{blue}{\frac{b - \frac{d \cdot a}{c}}{c}} \]
                  3. Recombined 2 regimes into one program.
                  4. Add Preprocessing

                  Alternative 7: 63.7% accurate, 0.9× speedup?

                  \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{a}{-d}\\ \mathbf{if}\;d \leq -3.5 \cdot 10^{+129}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;d \leq -7.8 \cdot 10^{-69}:\\ \;\;\;\;a \cdot \frac{-d}{\mathsf{fma}\left(d, d, c \cdot c\right)}\\ \mathbf{elif}\;d \leq 2.55 \cdot 10^{-110}:\\ \;\;\;\;\frac{b}{c}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
                  (FPCore (a b c d)
                   :precision binary64
                   (let* ((t_0 (/ a (- d))))
                     (if (<= d -3.5e+129)
                       t_0
                       (if (<= d -7.8e-69)
                         (* a (/ (- d) (fma d d (* c c))))
                         (if (<= d 2.55e-110) (/ b c) t_0)))))
                  double code(double a, double b, double c, double d) {
                  	double t_0 = a / -d;
                  	double tmp;
                  	if (d <= -3.5e+129) {
                  		tmp = t_0;
                  	} else if (d <= -7.8e-69) {
                  		tmp = a * (-d / fma(d, d, (c * c)));
                  	} else if (d <= 2.55e-110) {
                  		tmp = b / c;
                  	} else {
                  		tmp = t_0;
                  	}
                  	return tmp;
                  }
                  
                  function code(a, b, c, d)
                  	t_0 = Float64(a / Float64(-d))
                  	tmp = 0.0
                  	if (d <= -3.5e+129)
                  		tmp = t_0;
                  	elseif (d <= -7.8e-69)
                  		tmp = Float64(a * Float64(Float64(-d) / fma(d, d, Float64(c * c))));
                  	elseif (d <= 2.55e-110)
                  		tmp = Float64(b / c);
                  	else
                  		tmp = t_0;
                  	end
                  	return tmp
                  end
                  
                  code[a_, b_, c_, d_] := Block[{t$95$0 = N[(a / (-d)), $MachinePrecision]}, If[LessEqual[d, -3.5e+129], t$95$0, If[LessEqual[d, -7.8e-69], N[(a * N[((-d) / N[(d * d + N[(c * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[d, 2.55e-110], N[(b / c), $MachinePrecision], t$95$0]]]]
                  
                  \begin{array}{l}
                  
                  \\
                  \begin{array}{l}
                  t_0 := \frac{a}{-d}\\
                  \mathbf{if}\;d \leq -3.5 \cdot 10^{+129}:\\
                  \;\;\;\;t\_0\\
                  
                  \mathbf{elif}\;d \leq -7.8 \cdot 10^{-69}:\\
                  \;\;\;\;a \cdot \frac{-d}{\mathsf{fma}\left(d, d, c \cdot c\right)}\\
                  
                  \mathbf{elif}\;d \leq 2.55 \cdot 10^{-110}:\\
                  \;\;\;\;\frac{b}{c}\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;t\_0\\
                  
                  
                  \end{array}
                  \end{array}
                  
                  Derivation
                  1. Split input into 3 regimes
                  2. if d < -3.4999999999999998e129 or 2.5500000000000001e-110 < d

                    1. Initial program 50.1%

                      \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                    2. Add Preprocessing
                    3. Taylor expanded in c around 0

                      \[\leadsto \color{blue}{-1 \cdot \frac{a}{d}} \]
                    4. Step-by-step derivation
                      1. mul-1-negN/A

                        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{a}{d}\right)} \]
                      2. distribute-neg-frac2N/A

                        \[\leadsto \color{blue}{\frac{a}{\mathsf{neg}\left(d\right)}} \]
                      3. mul-1-negN/A

                        \[\leadsto \frac{a}{\color{blue}{-1 \cdot d}} \]
                      4. lower-/.f64N/A

                        \[\leadsto \color{blue}{\frac{a}{-1 \cdot d}} \]
                      5. mul-1-negN/A

                        \[\leadsto \frac{a}{\color{blue}{\mathsf{neg}\left(d\right)}} \]
                      6. lower-neg.f6475.6

                        \[\leadsto \frac{a}{\color{blue}{-d}} \]
                    5. Applied rewrites75.6%

                      \[\leadsto \color{blue}{\frac{a}{-d}} \]

                    if -3.4999999999999998e129 < d < -7.79999999999999961e-69

                    1. Initial program 88.1%

                      \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                    2. Add Preprocessing
                    3. Taylor expanded in c around inf

                      \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
                    4. Step-by-step derivation
                      1. lower-/.f64N/A

                        \[\leadsto \color{blue}{\frac{b + -1 \cdot \frac{a \cdot d}{c}}{c}} \]
                      2. mul-1-negN/A

                        \[\leadsto \frac{b + \color{blue}{\left(\mathsf{neg}\left(\frac{a \cdot d}{c}\right)\right)}}{c} \]
                      3. unsub-negN/A

                        \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
                      4. lower--.f64N/A

                        \[\leadsto \frac{\color{blue}{b - \frac{a \cdot d}{c}}}{c} \]
                      5. lower-/.f64N/A

                        \[\leadsto \frac{b - \color{blue}{\frac{a \cdot d}{c}}}{c} \]
                      6. *-commutativeN/A

                        \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
                      7. lower-*.f6443.4

                        \[\leadsto \frac{b - \frac{\color{blue}{d \cdot a}}{c}}{c} \]
                    5. Applied rewrites43.4%

                      \[\leadsto \color{blue}{\frac{b - \frac{d \cdot a}{c}}{c}} \]
                    6. Taylor expanded in b around 0

                      \[\leadsto \color{blue}{-1 \cdot \frac{a \cdot d}{{c}^{2} + {d}^{2}}} \]
                    7. Step-by-step derivation
                      1. mul-1-negN/A

                        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{a \cdot d}{{c}^{2} + {d}^{2}}\right)} \]
                      2. lower-neg.f64N/A

                        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{a \cdot d}{{c}^{2} + {d}^{2}}\right)} \]
                      3. associate-/l*N/A

                        \[\leadsto \mathsf{neg}\left(\color{blue}{a \cdot \frac{d}{{c}^{2} + {d}^{2}}}\right) \]
                      4. lower-*.f64N/A

                        \[\leadsto \mathsf{neg}\left(\color{blue}{a \cdot \frac{d}{{c}^{2} + {d}^{2}}}\right) \]
                      5. lower-/.f64N/A

                        \[\leadsto \mathsf{neg}\left(a \cdot \color{blue}{\frac{d}{{c}^{2} + {d}^{2}}}\right) \]
                      6. +-commutativeN/A

                        \[\leadsto \mathsf{neg}\left(a \cdot \frac{d}{\color{blue}{{d}^{2} + {c}^{2}}}\right) \]
                      7. unpow2N/A

                        \[\leadsto \mathsf{neg}\left(a \cdot \frac{d}{\color{blue}{d \cdot d} + {c}^{2}}\right) \]
                      8. lower-fma.f64N/A

                        \[\leadsto \mathsf{neg}\left(a \cdot \frac{d}{\color{blue}{\mathsf{fma}\left(d, d, {c}^{2}\right)}}\right) \]
                      9. unpow2N/A

                        \[\leadsto \mathsf{neg}\left(a \cdot \frac{d}{\mathsf{fma}\left(d, d, \color{blue}{c \cdot c}\right)}\right) \]
                      10. lower-*.f6469.9

                        \[\leadsto -a \cdot \frac{d}{\mathsf{fma}\left(d, d, \color{blue}{c \cdot c}\right)} \]
                    8. Applied rewrites69.9%

                      \[\leadsto \color{blue}{-a \cdot \frac{d}{\mathsf{fma}\left(d, d, c \cdot c\right)}} \]

                    if -7.79999999999999961e-69 < d < 2.5500000000000001e-110

                    1. Initial program 70.3%

                      \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                    2. Add Preprocessing
                    3. Taylor expanded in c around inf

                      \[\leadsto \color{blue}{\frac{b}{c}} \]
                    4. Step-by-step derivation
                      1. lower-/.f6474.2

                        \[\leadsto \color{blue}{\frac{b}{c}} \]
                    5. Applied rewrites74.2%

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

                    \[\leadsto \begin{array}{l} \mathbf{if}\;d \leq -3.5 \cdot 10^{+129}:\\ \;\;\;\;\frac{a}{-d}\\ \mathbf{elif}\;d \leq -7.8 \cdot 10^{-69}:\\ \;\;\;\;a \cdot \frac{-d}{\mathsf{fma}\left(d, d, c \cdot c\right)}\\ \mathbf{elif}\;d \leq 2.55 \cdot 10^{-110}:\\ \;\;\;\;\frac{b}{c}\\ \mathbf{else}:\\ \;\;\;\;\frac{a}{-d}\\ \end{array} \]
                  5. Add Preprocessing

                  Alternative 8: 62.1% accurate, 1.5× speedup?

                  \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{a}{-d}\\ \mathbf{if}\;d \leq -54000000000:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;d \leq 2.55 \cdot 10^{-110}:\\ \;\;\;\;\frac{b}{c}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
                  (FPCore (a b c d)
                   :precision binary64
                   (let* ((t_0 (/ a (- d))))
                     (if (<= d -54000000000.0) t_0 (if (<= d 2.55e-110) (/ b c) t_0))))
                  double code(double a, double b, double c, double d) {
                  	double t_0 = a / -d;
                  	double tmp;
                  	if (d <= -54000000000.0) {
                  		tmp = t_0;
                  	} else if (d <= 2.55e-110) {
                  		tmp = b / c;
                  	} else {
                  		tmp = t_0;
                  	}
                  	return tmp;
                  }
                  
                  real(8) function code(a, b, c, d)
                      real(8), intent (in) :: a
                      real(8), intent (in) :: b
                      real(8), intent (in) :: c
                      real(8), intent (in) :: d
                      real(8) :: t_0
                      real(8) :: tmp
                      t_0 = a / -d
                      if (d <= (-54000000000.0d0)) then
                          tmp = t_0
                      else if (d <= 2.55d-110) then
                          tmp = b / c
                      else
                          tmp = t_0
                      end if
                      code = tmp
                  end function
                  
                  public static double code(double a, double b, double c, double d) {
                  	double t_0 = a / -d;
                  	double tmp;
                  	if (d <= -54000000000.0) {
                  		tmp = t_0;
                  	} else if (d <= 2.55e-110) {
                  		tmp = b / c;
                  	} else {
                  		tmp = t_0;
                  	}
                  	return tmp;
                  }
                  
                  def code(a, b, c, d):
                  	t_0 = a / -d
                  	tmp = 0
                  	if d <= -54000000000.0:
                  		tmp = t_0
                  	elif d <= 2.55e-110:
                  		tmp = b / c
                  	else:
                  		tmp = t_0
                  	return tmp
                  
                  function code(a, b, c, d)
                  	t_0 = Float64(a / Float64(-d))
                  	tmp = 0.0
                  	if (d <= -54000000000.0)
                  		tmp = t_0;
                  	elseif (d <= 2.55e-110)
                  		tmp = Float64(b / c);
                  	else
                  		tmp = t_0;
                  	end
                  	return tmp
                  end
                  
                  function tmp_2 = code(a, b, c, d)
                  	t_0 = a / -d;
                  	tmp = 0.0;
                  	if (d <= -54000000000.0)
                  		tmp = t_0;
                  	elseif (d <= 2.55e-110)
                  		tmp = b / c;
                  	else
                  		tmp = t_0;
                  	end
                  	tmp_2 = tmp;
                  end
                  
                  code[a_, b_, c_, d_] := Block[{t$95$0 = N[(a / (-d)), $MachinePrecision]}, If[LessEqual[d, -54000000000.0], t$95$0, If[LessEqual[d, 2.55e-110], N[(b / c), $MachinePrecision], t$95$0]]]
                  
                  \begin{array}{l}
                  
                  \\
                  \begin{array}{l}
                  t_0 := \frac{a}{-d}\\
                  \mathbf{if}\;d \leq -54000000000:\\
                  \;\;\;\;t\_0\\
                  
                  \mathbf{elif}\;d \leq 2.55 \cdot 10^{-110}:\\
                  \;\;\;\;\frac{b}{c}\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;t\_0\\
                  
                  
                  \end{array}
                  \end{array}
                  
                  Derivation
                  1. Split input into 2 regimes
                  2. if d < -5.4e10 or 2.5500000000000001e-110 < d

                    1. Initial program 56.7%

                      \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                    2. Add Preprocessing
                    3. Taylor expanded in c around 0

                      \[\leadsto \color{blue}{-1 \cdot \frac{a}{d}} \]
                    4. Step-by-step derivation
                      1. mul-1-negN/A

                        \[\leadsto \color{blue}{\mathsf{neg}\left(\frac{a}{d}\right)} \]
                      2. distribute-neg-frac2N/A

                        \[\leadsto \color{blue}{\frac{a}{\mathsf{neg}\left(d\right)}} \]
                      3. mul-1-negN/A

                        \[\leadsto \frac{a}{\color{blue}{-1 \cdot d}} \]
                      4. lower-/.f64N/A

                        \[\leadsto \color{blue}{\frac{a}{-1 \cdot d}} \]
                      5. mul-1-negN/A

                        \[\leadsto \frac{a}{\color{blue}{\mathsf{neg}\left(d\right)}} \]
                      6. lower-neg.f6474.6

                        \[\leadsto \frac{a}{\color{blue}{-d}} \]
                    5. Applied rewrites74.6%

                      \[\leadsto \color{blue}{\frac{a}{-d}} \]

                    if -5.4e10 < d < 2.5500000000000001e-110

                    1. Initial program 73.0%

                      \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                    2. Add Preprocessing
                    3. Taylor expanded in c around inf

                      \[\leadsto \color{blue}{\frac{b}{c}} \]
                    4. Step-by-step derivation
                      1. lower-/.f6469.5

                        \[\leadsto \color{blue}{\frac{b}{c}} \]
                    5. Applied rewrites69.5%

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

                  Alternative 9: 43.0% accurate, 3.2× speedup?

                  \[\begin{array}{l} \\ \frac{b}{c} \end{array} \]
                  (FPCore (a b c d) :precision binary64 (/ b c))
                  double code(double a, double b, double c, double d) {
                  	return b / c;
                  }
                  
                  real(8) function code(a, b, c, d)
                      real(8), intent (in) :: a
                      real(8), intent (in) :: b
                      real(8), intent (in) :: c
                      real(8), intent (in) :: d
                      code = b / c
                  end function
                  
                  public static double code(double a, double b, double c, double d) {
                  	return b / c;
                  }
                  
                  def code(a, b, c, d):
                  	return b / c
                  
                  function code(a, b, c, d)
                  	return Float64(b / c)
                  end
                  
                  function tmp = code(a, b, c, d)
                  	tmp = b / c;
                  end
                  
                  code[a_, b_, c_, d_] := N[(b / c), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \frac{b}{c}
                  \end{array}
                  
                  Derivation
                  1. Initial program 64.0%

                    \[\frac{b \cdot c - a \cdot d}{c \cdot c + d \cdot d} \]
                  2. Add Preprocessing
                  3. Taylor expanded in c around inf

                    \[\leadsto \color{blue}{\frac{b}{c}} \]
                  4. Step-by-step derivation
                    1. lower-/.f6441.3

                      \[\leadsto \color{blue}{\frac{b}{c}} \]
                  5. Applied rewrites41.3%

                    \[\leadsto \color{blue}{\frac{b}{c}} \]
                  6. Add Preprocessing

                  Developer Target 1: 99.3% accurate, 0.6× speedup?

                  \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\left|d\right| < \left|c\right|:\\ \;\;\;\;\frac{b - a \cdot \frac{d}{c}}{c + d \cdot \frac{d}{c}}\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(-a\right) + b \cdot \frac{c}{d}}{d + c \cdot \frac{c}{d}}\\ \end{array} \end{array} \]
                  (FPCore (a b c d)
                   :precision binary64
                   (if (< (fabs d) (fabs c))
                     (/ (- b (* a (/ d c))) (+ c (* d (/ d c))))
                     (/ (+ (- a) (* b (/ c d))) (+ d (* c (/ c d))))))
                  double code(double a, double b, double c, double d) {
                  	double tmp;
                  	if (fabs(d) < fabs(c)) {
                  		tmp = (b - (a * (d / c))) / (c + (d * (d / c)));
                  	} else {
                  		tmp = (-a + (b * (c / d))) / (d + (c * (c / d)));
                  	}
                  	return tmp;
                  }
                  
                  real(8) function code(a, b, c, d)
                      real(8), intent (in) :: a
                      real(8), intent (in) :: b
                      real(8), intent (in) :: c
                      real(8), intent (in) :: d
                      real(8) :: tmp
                      if (abs(d) < abs(c)) then
                          tmp = (b - (a * (d / c))) / (c + (d * (d / c)))
                      else
                          tmp = (-a + (b * (c / d))) / (d + (c * (c / d)))
                      end if
                      code = tmp
                  end function
                  
                  public static double code(double a, double b, double c, double d) {
                  	double tmp;
                  	if (Math.abs(d) < Math.abs(c)) {
                  		tmp = (b - (a * (d / c))) / (c + (d * (d / c)));
                  	} else {
                  		tmp = (-a + (b * (c / d))) / (d + (c * (c / d)));
                  	}
                  	return tmp;
                  }
                  
                  def code(a, b, c, d):
                  	tmp = 0
                  	if math.fabs(d) < math.fabs(c):
                  		tmp = (b - (a * (d / c))) / (c + (d * (d / c)))
                  	else:
                  		tmp = (-a + (b * (c / d))) / (d + (c * (c / d)))
                  	return tmp
                  
                  function code(a, b, c, d)
                  	tmp = 0.0
                  	if (abs(d) < abs(c))
                  		tmp = Float64(Float64(b - Float64(a * Float64(d / c))) / Float64(c + Float64(d * Float64(d / c))));
                  	else
                  		tmp = Float64(Float64(Float64(-a) + Float64(b * Float64(c / d))) / Float64(d + Float64(c * Float64(c / d))));
                  	end
                  	return tmp
                  end
                  
                  function tmp_2 = code(a, b, c, d)
                  	tmp = 0.0;
                  	if (abs(d) < abs(c))
                  		tmp = (b - (a * (d / c))) / (c + (d * (d / c)));
                  	else
                  		tmp = (-a + (b * (c / d))) / (d + (c * (c / d)));
                  	end
                  	tmp_2 = tmp;
                  end
                  
                  code[a_, b_, c_, d_] := If[Less[N[Abs[d], $MachinePrecision], N[Abs[c], $MachinePrecision]], N[(N[(b - N[(a * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(c + N[(d * N[(d / c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[((-a) + N[(b * N[(c / d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(d + N[(c * N[(c / d), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                  
                  \begin{array}{l}
                  
                  \\
                  \begin{array}{l}
                  \mathbf{if}\;\left|d\right| < \left|c\right|:\\
                  \;\;\;\;\frac{b - a \cdot \frac{d}{c}}{c + d \cdot \frac{d}{c}}\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;\frac{\left(-a\right) + b \cdot \frac{c}{d}}{d + c \cdot \frac{c}{d}}\\
                  
                  
                  \end{array}
                  \end{array}
                  

                  Reproduce

                  ?
                  herbie shell --seed 2024219 
                  (FPCore (a b c d)
                    :name "Complex division, imag part"
                    :precision binary64
                  
                    :alt
                    (! :herbie-platform default (if (< (fabs d) (fabs c)) (/ (- b (* a (/ d c))) (+ c (* d (/ d c)))) (/ (+ (- a) (* b (/ c d))) (+ d (* c (/ c d))))))
                  
                    (/ (- (* b c) (* a d)) (+ (* c c) (* d d))))