quad2m (problem 3.2.1, negative)

Percentage Accurate: 51.6% → 85.7%
Time: 8.1s
Alternatives: 9
Speedup: 1.7×

Specification

?
\[\begin{array}{l} \\ \frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (/ (- (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))
double code(double a, double b_2, double c) {
	return (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a;
}
real(8) function code(a, b_2, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    code = (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a
end function
public static double code(double a, double b_2, double c) {
	return (-b_2 - Math.sqrt(((b_2 * b_2) - (a * c)))) / a;
}
def code(a, b_2, c):
	return (-b_2 - math.sqrt(((b_2 * b_2) - (a * c)))) / a
function code(a, b_2, c)
	return Float64(Float64(Float64(-b_2) - sqrt(Float64(Float64(b_2 * b_2) - Float64(a * c)))) / a)
end
function tmp = code(a, b_2, c)
	tmp = (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a;
end
code[a_, b$95$2_, c_] := N[(N[((-b$95$2) - N[Sqrt[N[(N[(b$95$2 * b$95$2), $MachinePrecision] - N[(a * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a}
\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: 51.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (/ (- (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))
double code(double a, double b_2, double c) {
	return (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a;
}
real(8) function code(a, b_2, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b_2
    real(8), intent (in) :: c
    code = (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a
end function
public static double code(double a, double b_2, double c) {
	return (-b_2 - Math.sqrt(((b_2 * b_2) - (a * c)))) / a;
}
def code(a, b_2, c):
	return (-b_2 - math.sqrt(((b_2 * b_2) - (a * c)))) / a
function code(a, b_2, c)
	return Float64(Float64(Float64(-b_2) - sqrt(Float64(Float64(b_2 * b_2) - Float64(a * c)))) / a)
end
function tmp = code(a, b_2, c)
	tmp = (-b_2 - sqrt(((b_2 * b_2) - (a * c)))) / a;
end
code[a_, b$95$2_, c_] := N[(N[((-b$95$2) - N[Sqrt[N[(N[(b$95$2 * b$95$2), $MachinePrecision] - N[(a * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / a), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a}
\end{array}

Alternative 1: 85.7% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b\_2 \leq -1.25 \cdot 10^{-90}:\\ \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\ \mathbf{elif}\;b\_2 \leq 4 \cdot 10^{+137}:\\ \;\;\;\;\frac{-b\_2}{a} - \frac{\sqrt{\mathsf{fma}\left(-a, c, b\_2 \cdot b\_2\right)}}{a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-2 \cdot b\_2}{a}\\ \end{array} \end{array} \]
(FPCore (a b_2 c)
 :precision binary64
 (if (<= b_2 -1.25e-90)
   (/ (* -0.5 c) b_2)
   (if (<= b_2 4e+137)
     (- (/ (- b_2) a) (/ (sqrt (fma (- a) c (* b_2 b_2))) a))
     (/ (* -2.0 b_2) a))))
double code(double a, double b_2, double c) {
	double tmp;
	if (b_2 <= -1.25e-90) {
		tmp = (-0.5 * c) / b_2;
	} else if (b_2 <= 4e+137) {
		tmp = (-b_2 / a) - (sqrt(fma(-a, c, (b_2 * b_2))) / a);
	} else {
		tmp = (-2.0 * b_2) / a;
	}
	return tmp;
}
function code(a, b_2, c)
	tmp = 0.0
	if (b_2 <= -1.25e-90)
		tmp = Float64(Float64(-0.5 * c) / b_2);
	elseif (b_2 <= 4e+137)
		tmp = Float64(Float64(Float64(-b_2) / a) - Float64(sqrt(fma(Float64(-a), c, Float64(b_2 * b_2))) / a));
	else
		tmp = Float64(Float64(-2.0 * b_2) / a);
	end
	return tmp
end
code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -1.25e-90], N[(N[(-0.5 * c), $MachinePrecision] / b$95$2), $MachinePrecision], If[LessEqual[b$95$2, 4e+137], N[(N[((-b$95$2) / a), $MachinePrecision] - N[(N[Sqrt[N[((-a) * c + N[(b$95$2 * b$95$2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / a), $MachinePrecision]), $MachinePrecision], N[(N[(-2.0 * b$95$2), $MachinePrecision] / a), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;b\_2 \leq -1.25 \cdot 10^{-90}:\\
\;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\

\mathbf{elif}\;b\_2 \leq 4 \cdot 10^{+137}:\\
\;\;\;\;\frac{-b\_2}{a} - \frac{\sqrt{\mathsf{fma}\left(-a, c, b\_2 \cdot b\_2\right)}}{a}\\

\mathbf{else}:\\
\;\;\;\;\frac{-2 \cdot b\_2}{a}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if b_2 < -1.25000000000000005e-90

    1. Initial program 15.3%

      \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
    2. Add Preprocessing
    3. Taylor expanded in b_2 around -inf

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
    4. Step-by-step derivation
      1. lower-*.f64N/A

        \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
      2. lower-/.f6489.9

        \[\leadsto -0.5 \cdot \color{blue}{\frac{c}{b\_2}} \]
    5. Applied rewrites89.9%

      \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b\_2}} \]
    6. Step-by-step derivation
      1. Applied rewrites89.9%

        \[\leadsto \frac{-0.5 \cdot c}{\color{blue}{b\_2}} \]

      if -1.25000000000000005e-90 < b_2 < 4.0000000000000001e137

      1. Initial program 83.6%

        \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
      2. Add Preprocessing
      3. Applied rewrites39.5%

        \[\leadsto \frac{\left(-b\_2\right) - \sqrt{\color{blue}{\frac{{b\_2}^{6} - {\left(c \cdot a\right)}^{3}}{\mathsf{fma}\left(\mathsf{fma}\left(c, a, b\_2 \cdot b\_2\right), c \cdot a, {b\_2}^{4}\right)}}}}{a} \]
      4. Applied rewrites83.6%

        \[\leadsto \color{blue}{\frac{-b\_2}{a} - \frac{\sqrt{\mathsf{fma}\left(-a, c, b\_2 \cdot b\_2\right)}}{a}} \]

      if 4.0000000000000001e137 < b_2

      1. Initial program 45.3%

        \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
      2. Add Preprocessing
      3. Taylor expanded in a around 0

        \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
      4. Step-by-step derivation
        1. lower-*.f64100.0

          \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
      5. Applied rewrites100.0%

        \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
    7. Recombined 3 regimes into one program.
    8. Add Preprocessing

    Alternative 2: 85.7% accurate, 0.8× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b\_2 \leq -1.25 \cdot 10^{-90}:\\ \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\ \mathbf{elif}\;b\_2 \leq 4 \cdot 10^{+137}:\\ \;\;\;\;\frac{b\_2 + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{-a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-2 \cdot b\_2}{a}\\ \end{array} \end{array} \]
    (FPCore (a b_2 c)
     :precision binary64
     (if (<= b_2 -1.25e-90)
       (/ (* -0.5 c) b_2)
       (if (<= b_2 4e+137)
         (/ (+ b_2 (sqrt (- (* b_2 b_2) (* a c)))) (- a))
         (/ (* -2.0 b_2) a))))
    double code(double a, double b_2, double c) {
    	double tmp;
    	if (b_2 <= -1.25e-90) {
    		tmp = (-0.5 * c) / b_2;
    	} else if (b_2 <= 4e+137) {
    		tmp = (b_2 + sqrt(((b_2 * b_2) - (a * c)))) / -a;
    	} else {
    		tmp = (-2.0 * b_2) / a;
    	}
    	return tmp;
    }
    
    real(8) function code(a, b_2, c)
        real(8), intent (in) :: a
        real(8), intent (in) :: b_2
        real(8), intent (in) :: c
        real(8) :: tmp
        if (b_2 <= (-1.25d-90)) then
            tmp = ((-0.5d0) * c) / b_2
        else if (b_2 <= 4d+137) then
            tmp = (b_2 + sqrt(((b_2 * b_2) - (a * c)))) / -a
        else
            tmp = ((-2.0d0) * b_2) / a
        end if
        code = tmp
    end function
    
    public static double code(double a, double b_2, double c) {
    	double tmp;
    	if (b_2 <= -1.25e-90) {
    		tmp = (-0.5 * c) / b_2;
    	} else if (b_2 <= 4e+137) {
    		tmp = (b_2 + Math.sqrt(((b_2 * b_2) - (a * c)))) / -a;
    	} else {
    		tmp = (-2.0 * b_2) / a;
    	}
    	return tmp;
    }
    
    def code(a, b_2, c):
    	tmp = 0
    	if b_2 <= -1.25e-90:
    		tmp = (-0.5 * c) / b_2
    	elif b_2 <= 4e+137:
    		tmp = (b_2 + math.sqrt(((b_2 * b_2) - (a * c)))) / -a
    	else:
    		tmp = (-2.0 * b_2) / a
    	return tmp
    
    function code(a, b_2, c)
    	tmp = 0.0
    	if (b_2 <= -1.25e-90)
    		tmp = Float64(Float64(-0.5 * c) / b_2);
    	elseif (b_2 <= 4e+137)
    		tmp = Float64(Float64(b_2 + sqrt(Float64(Float64(b_2 * b_2) - Float64(a * c)))) / Float64(-a));
    	else
    		tmp = Float64(Float64(-2.0 * b_2) / a);
    	end
    	return tmp
    end
    
    function tmp_2 = code(a, b_2, c)
    	tmp = 0.0;
    	if (b_2 <= -1.25e-90)
    		tmp = (-0.5 * c) / b_2;
    	elseif (b_2 <= 4e+137)
    		tmp = (b_2 + sqrt(((b_2 * b_2) - (a * c)))) / -a;
    	else
    		tmp = (-2.0 * b_2) / a;
    	end
    	tmp_2 = tmp;
    end
    
    code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -1.25e-90], N[(N[(-0.5 * c), $MachinePrecision] / b$95$2), $MachinePrecision], If[LessEqual[b$95$2, 4e+137], N[(N[(b$95$2 + N[Sqrt[N[(N[(b$95$2 * b$95$2), $MachinePrecision] - N[(a * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / (-a)), $MachinePrecision], N[(N[(-2.0 * b$95$2), $MachinePrecision] / a), $MachinePrecision]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;b\_2 \leq -1.25 \cdot 10^{-90}:\\
    \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\
    
    \mathbf{elif}\;b\_2 \leq 4 \cdot 10^{+137}:\\
    \;\;\;\;\frac{b\_2 + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{-a}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{-2 \cdot b\_2}{a}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if b_2 < -1.25000000000000005e-90

      1. Initial program 15.3%

        \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
      2. Add Preprocessing
      3. Taylor expanded in b_2 around -inf

        \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
      4. Step-by-step derivation
        1. lower-*.f64N/A

          \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
        2. lower-/.f6489.9

          \[\leadsto -0.5 \cdot \color{blue}{\frac{c}{b\_2}} \]
      5. Applied rewrites89.9%

        \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b\_2}} \]
      6. Step-by-step derivation
        1. Applied rewrites89.9%

          \[\leadsto \frac{-0.5 \cdot c}{\color{blue}{b\_2}} \]

        if -1.25000000000000005e-90 < b_2 < 4.0000000000000001e137

        1. Initial program 83.6%

          \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
        2. Add Preprocessing

        if 4.0000000000000001e137 < b_2

        1. Initial program 45.3%

          \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
        2. Add Preprocessing
        3. Taylor expanded in a around 0

          \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
        4. Step-by-step derivation
          1. lower-*.f64100.0

            \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
        5. Applied rewrites100.0%

          \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
      7. Recombined 3 regimes into one program.
      8. Final simplification89.2%

        \[\leadsto \begin{array}{l} \mathbf{if}\;b\_2 \leq -1.25 \cdot 10^{-90}:\\ \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\ \mathbf{elif}\;b\_2 \leq 4 \cdot 10^{+137}:\\ \;\;\;\;\frac{b\_2 + \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{-a}\\ \mathbf{else}:\\ \;\;\;\;\frac{-2 \cdot b\_2}{a}\\ \end{array} \]
      9. Add Preprocessing

      Alternative 3: 81.3% accurate, 0.9× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b\_2 \leq -1.25 \cdot 10^{-90}:\\ \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\ \mathbf{elif}\;b\_2 \leq 3.3 \cdot 10^{-66}:\\ \;\;\;\;\frac{b\_2 + \sqrt{\left(-c\right) \cdot a}}{-a}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{0.5}{b\_2}, c, \frac{b\_2}{a} \cdot -2\right)\\ \end{array} \end{array} \]
      (FPCore (a b_2 c)
       :precision binary64
       (if (<= b_2 -1.25e-90)
         (/ (* -0.5 c) b_2)
         (if (<= b_2 3.3e-66)
           (/ (+ b_2 (sqrt (* (- c) a))) (- a))
           (fma (/ 0.5 b_2) c (* (/ b_2 a) -2.0)))))
      double code(double a, double b_2, double c) {
      	double tmp;
      	if (b_2 <= -1.25e-90) {
      		tmp = (-0.5 * c) / b_2;
      	} else if (b_2 <= 3.3e-66) {
      		tmp = (b_2 + sqrt((-c * a))) / -a;
      	} else {
      		tmp = fma((0.5 / b_2), c, ((b_2 / a) * -2.0));
      	}
      	return tmp;
      }
      
      function code(a, b_2, c)
      	tmp = 0.0
      	if (b_2 <= -1.25e-90)
      		tmp = Float64(Float64(-0.5 * c) / b_2);
      	elseif (b_2 <= 3.3e-66)
      		tmp = Float64(Float64(b_2 + sqrt(Float64(Float64(-c) * a))) / Float64(-a));
      	else
      		tmp = fma(Float64(0.5 / b_2), c, Float64(Float64(b_2 / a) * -2.0));
      	end
      	return tmp
      end
      
      code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -1.25e-90], N[(N[(-0.5 * c), $MachinePrecision] / b$95$2), $MachinePrecision], If[LessEqual[b$95$2, 3.3e-66], N[(N[(b$95$2 + N[Sqrt[N[((-c) * a), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / (-a)), $MachinePrecision], N[(N[(0.5 / b$95$2), $MachinePrecision] * c + N[(N[(b$95$2 / a), $MachinePrecision] * -2.0), $MachinePrecision]), $MachinePrecision]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;b\_2 \leq -1.25 \cdot 10^{-90}:\\
      \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\
      
      \mathbf{elif}\;b\_2 \leq 3.3 \cdot 10^{-66}:\\
      \;\;\;\;\frac{b\_2 + \sqrt{\left(-c\right) \cdot a}}{-a}\\
      
      \mathbf{else}:\\
      \;\;\;\;\mathsf{fma}\left(\frac{0.5}{b\_2}, c, \frac{b\_2}{a} \cdot -2\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if b_2 < -1.25000000000000005e-90

        1. Initial program 15.3%

          \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
        2. Add Preprocessing
        3. Taylor expanded in b_2 around -inf

          \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
        4. Step-by-step derivation
          1. lower-*.f64N/A

            \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
          2. lower-/.f6489.9

            \[\leadsto -0.5 \cdot \color{blue}{\frac{c}{b\_2}} \]
        5. Applied rewrites89.9%

          \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b\_2}} \]
        6. Step-by-step derivation
          1. Applied rewrites89.9%

            \[\leadsto \frac{-0.5 \cdot c}{\color{blue}{b\_2}} \]

          if -1.25000000000000005e-90 < b_2 < 3.2999999999999999e-66

          1. Initial program 76.4%

            \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
          2. Add Preprocessing
          3. Taylor expanded in a around inf

            \[\leadsto \frac{\left(-b\_2\right) - \sqrt{\color{blue}{-1 \cdot \left(a \cdot c\right)}}}{a} \]
          4. Step-by-step derivation
            1. mul-1-negN/A

              \[\leadsto \frac{\left(-b\_2\right) - \sqrt{\color{blue}{\mathsf{neg}\left(a \cdot c\right)}}}{a} \]
            2. *-commutativeN/A

              \[\leadsto \frac{\left(-b\_2\right) - \sqrt{\mathsf{neg}\left(\color{blue}{c \cdot a}\right)}}{a} \]
            3. distribute-lft-neg-inN/A

              \[\leadsto \frac{\left(-b\_2\right) - \sqrt{\color{blue}{\left(\mathsf{neg}\left(c\right)\right) \cdot a}}}{a} \]
            4. lower-*.f64N/A

              \[\leadsto \frac{\left(-b\_2\right) - \sqrt{\color{blue}{\left(\mathsf{neg}\left(c\right)\right) \cdot a}}}{a} \]
            5. lower-neg.f6473.2

              \[\leadsto \frac{\left(-b\_2\right) - \sqrt{\color{blue}{\left(-c\right)} \cdot a}}{a} \]
          5. Applied rewrites73.2%

            \[\leadsto \frac{\left(-b\_2\right) - \sqrt{\color{blue}{\left(-c\right) \cdot a}}}{a} \]

          if 3.2999999999999999e-66 < b_2

          1. Initial program 68.4%

            \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
          2. Add Preprocessing
          3. Taylor expanded in c around 0

            \[\leadsto \color{blue}{-2 \cdot \frac{b\_2}{a} + \frac{1}{2} \cdot \frac{c}{b\_2}} \]
          4. Step-by-step derivation
            1. +-commutativeN/A

              \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{c}{b\_2} + -2 \cdot \frac{b\_2}{a}} \]
            2. associate-*r/N/A

              \[\leadsto \color{blue}{\frac{\frac{1}{2} \cdot c}{b\_2}} + -2 \cdot \frac{b\_2}{a} \]
            3. associate-*l/N/A

              \[\leadsto \color{blue}{\frac{\frac{1}{2}}{b\_2} \cdot c} + -2 \cdot \frac{b\_2}{a} \]
            4. metadata-evalN/A

              \[\leadsto \frac{\color{blue}{\frac{1}{2} \cdot 1}}{b\_2} \cdot c + -2 \cdot \frac{b\_2}{a} \]
            5. associate-*r/N/A

              \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{b\_2}\right)} \cdot c + -2 \cdot \frac{b\_2}{a} \]
            6. lower-fma.f64N/A

              \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{2} \cdot \frac{1}{b\_2}, c, -2 \cdot \frac{b\_2}{a}\right)} \]
            7. associate-*r/N/A

              \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{\frac{1}{2} \cdot 1}{b\_2}}, c, -2 \cdot \frac{b\_2}{a}\right) \]
            8. metadata-evalN/A

              \[\leadsto \mathsf{fma}\left(\frac{\color{blue}{\frac{1}{2}}}{b\_2}, c, -2 \cdot \frac{b\_2}{a}\right) \]
            9. lower-/.f64N/A

              \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{\frac{1}{2}}{b\_2}}, c, -2 \cdot \frac{b\_2}{a}\right) \]
            10. *-commutativeN/A

              \[\leadsto \mathsf{fma}\left(\frac{\frac{1}{2}}{b\_2}, c, \color{blue}{\frac{b\_2}{a} \cdot -2}\right) \]
            11. lower-*.f64N/A

              \[\leadsto \mathsf{fma}\left(\frac{\frac{1}{2}}{b\_2}, c, \color{blue}{\frac{b\_2}{a} \cdot -2}\right) \]
            12. lower-/.f6491.0

              \[\leadsto \mathsf{fma}\left(\frac{0.5}{b\_2}, c, \color{blue}{\frac{b\_2}{a}} \cdot -2\right) \]
          5. Applied rewrites91.0%

            \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{0.5}{b\_2}, c, \frac{b\_2}{a} \cdot -2\right)} \]
        7. Recombined 3 regimes into one program.
        8. Final simplification86.3%

          \[\leadsto \begin{array}{l} \mathbf{if}\;b\_2 \leq -1.25 \cdot 10^{-90}:\\ \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\ \mathbf{elif}\;b\_2 \leq 3.3 \cdot 10^{-66}:\\ \;\;\;\;\frac{b\_2 + \sqrt{\left(-c\right) \cdot a}}{-a}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{0.5}{b\_2}, c, \frac{b\_2}{a} \cdot -2\right)\\ \end{array} \]
        9. Add Preprocessing

        Alternative 4: 68.2% accurate, 1.0× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b\_2 \leq -5 \cdot 10^{-310}:\\ \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{0.5}{b\_2}, c, \frac{b\_2}{a} \cdot -2\right)\\ \end{array} \end{array} \]
        (FPCore (a b_2 c)
         :precision binary64
         (if (<= b_2 -5e-310)
           (/ (* -0.5 c) b_2)
           (fma (/ 0.5 b_2) c (* (/ b_2 a) -2.0))))
        double code(double a, double b_2, double c) {
        	double tmp;
        	if (b_2 <= -5e-310) {
        		tmp = (-0.5 * c) / b_2;
        	} else {
        		tmp = fma((0.5 / b_2), c, ((b_2 / a) * -2.0));
        	}
        	return tmp;
        }
        
        function code(a, b_2, c)
        	tmp = 0.0
        	if (b_2 <= -5e-310)
        		tmp = Float64(Float64(-0.5 * c) / b_2);
        	else
        		tmp = fma(Float64(0.5 / b_2), c, Float64(Float64(b_2 / a) * -2.0));
        	end
        	return tmp
        end
        
        code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -5e-310], N[(N[(-0.5 * c), $MachinePrecision] / b$95$2), $MachinePrecision], N[(N[(0.5 / b$95$2), $MachinePrecision] * c + N[(N[(b$95$2 / a), $MachinePrecision] * -2.0), $MachinePrecision]), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;b\_2 \leq -5 \cdot 10^{-310}:\\
        \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\
        
        \mathbf{else}:\\
        \;\;\;\;\mathsf{fma}\left(\frac{0.5}{b\_2}, c, \frac{b\_2}{a} \cdot -2\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if b_2 < -4.999999999999985e-310

          1. Initial program 27.3%

            \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
          2. Add Preprocessing
          3. Taylor expanded in b_2 around -inf

            \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
          4. Step-by-step derivation
            1. lower-*.f64N/A

              \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
            2. lower-/.f6473.3

              \[\leadsto -0.5 \cdot \color{blue}{\frac{c}{b\_2}} \]
          5. Applied rewrites73.3%

            \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b\_2}} \]
          6. Step-by-step derivation
            1. Applied rewrites73.3%

              \[\leadsto \frac{-0.5 \cdot c}{\color{blue}{b\_2}} \]

            if -4.999999999999985e-310 < b_2

            1. Initial program 72.6%

              \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
            2. Add Preprocessing
            3. Taylor expanded in c around 0

              \[\leadsto \color{blue}{-2 \cdot \frac{b\_2}{a} + \frac{1}{2} \cdot \frac{c}{b\_2}} \]
            4. Step-by-step derivation
              1. +-commutativeN/A

                \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{c}{b\_2} + -2 \cdot \frac{b\_2}{a}} \]
              2. associate-*r/N/A

                \[\leadsto \color{blue}{\frac{\frac{1}{2} \cdot c}{b\_2}} + -2 \cdot \frac{b\_2}{a} \]
              3. associate-*l/N/A

                \[\leadsto \color{blue}{\frac{\frac{1}{2}}{b\_2} \cdot c} + -2 \cdot \frac{b\_2}{a} \]
              4. metadata-evalN/A

                \[\leadsto \frac{\color{blue}{\frac{1}{2} \cdot 1}}{b\_2} \cdot c + -2 \cdot \frac{b\_2}{a} \]
              5. associate-*r/N/A

                \[\leadsto \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{b\_2}\right)} \cdot c + -2 \cdot \frac{b\_2}{a} \]
              6. lower-fma.f64N/A

                \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{1}{2} \cdot \frac{1}{b\_2}, c, -2 \cdot \frac{b\_2}{a}\right)} \]
              7. associate-*r/N/A

                \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{\frac{1}{2} \cdot 1}{b\_2}}, c, -2 \cdot \frac{b\_2}{a}\right) \]
              8. metadata-evalN/A

                \[\leadsto \mathsf{fma}\left(\frac{\color{blue}{\frac{1}{2}}}{b\_2}, c, -2 \cdot \frac{b\_2}{a}\right) \]
              9. lower-/.f64N/A

                \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{\frac{1}{2}}{b\_2}}, c, -2 \cdot \frac{b\_2}{a}\right) \]
              10. *-commutativeN/A

                \[\leadsto \mathsf{fma}\left(\frac{\frac{1}{2}}{b\_2}, c, \color{blue}{\frac{b\_2}{a} \cdot -2}\right) \]
              11. lower-*.f64N/A

                \[\leadsto \mathsf{fma}\left(\frac{\frac{1}{2}}{b\_2}, c, \color{blue}{\frac{b\_2}{a} \cdot -2}\right) \]
              12. lower-/.f6470.8

                \[\leadsto \mathsf{fma}\left(\frac{0.5}{b\_2}, c, \color{blue}{\frac{b\_2}{a}} \cdot -2\right) \]
            5. Applied rewrites70.8%

              \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{0.5}{b\_2}, c, \frac{b\_2}{a} \cdot -2\right)} \]
          7. Recombined 2 regimes into one program.
          8. Add Preprocessing

          Alternative 5: 68.1% accurate, 1.0× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b\_2 \leq -5 \cdot 10^{-310}:\\ \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(b\_2, \frac{-2}{a}, 0.5 \cdot \frac{c}{b\_2}\right)\\ \end{array} \end{array} \]
          (FPCore (a b_2 c)
           :precision binary64
           (if (<= b_2 -5e-310)
             (/ (* -0.5 c) b_2)
             (fma b_2 (/ -2.0 a) (* 0.5 (/ c b_2)))))
          double code(double a, double b_2, double c) {
          	double tmp;
          	if (b_2 <= -5e-310) {
          		tmp = (-0.5 * c) / b_2;
          	} else {
          		tmp = fma(b_2, (-2.0 / a), (0.5 * (c / b_2)));
          	}
          	return tmp;
          }
          
          function code(a, b_2, c)
          	tmp = 0.0
          	if (b_2 <= -5e-310)
          		tmp = Float64(Float64(-0.5 * c) / b_2);
          	else
          		tmp = fma(b_2, Float64(-2.0 / a), Float64(0.5 * Float64(c / b_2)));
          	end
          	return tmp
          end
          
          code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -5e-310], N[(N[(-0.5 * c), $MachinePrecision] / b$95$2), $MachinePrecision], N[(b$95$2 * N[(-2.0 / a), $MachinePrecision] + N[(0.5 * N[(c / b$95$2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;b\_2 \leq -5 \cdot 10^{-310}:\\
          \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\
          
          \mathbf{else}:\\
          \;\;\;\;\mathsf{fma}\left(b\_2, \frac{-2}{a}, 0.5 \cdot \frac{c}{b\_2}\right)\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if b_2 < -4.999999999999985e-310

            1. Initial program 27.3%

              \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
            2. Add Preprocessing
            3. Taylor expanded in b_2 around -inf

              \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
            4. Step-by-step derivation
              1. lower-*.f64N/A

                \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
              2. lower-/.f6473.3

                \[\leadsto -0.5 \cdot \color{blue}{\frac{c}{b\_2}} \]
            5. Applied rewrites73.3%

              \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b\_2}} \]
            6. Step-by-step derivation
              1. Applied rewrites73.3%

                \[\leadsto \frac{-0.5 \cdot c}{\color{blue}{b\_2}} \]

              if -4.999999999999985e-310 < b_2

              1. Initial program 72.6%

                \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
              2. Add Preprocessing
              3. Taylor expanded in b_2 around -inf

                \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
              4. Step-by-step derivation
                1. lower-*.f64N/A

                  \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
                2. lower-/.f642.2

                  \[\leadsto -0.5 \cdot \color{blue}{\frac{c}{b\_2}} \]
              5. Applied rewrites2.2%

                \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b\_2}} \]
              6. Taylor expanded in c around 0

                \[\leadsto \color{blue}{-2 \cdot \frac{b\_2}{a} + \frac{1}{2} \cdot \frac{c}{b\_2}} \]
              7. Step-by-step derivation
                1. +-commutativeN/A

                  \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{c}{b\_2} + -2 \cdot \frac{b\_2}{a}} \]
                2. *-commutativeN/A

                  \[\leadsto \color{blue}{\frac{c}{b\_2} \cdot \frac{1}{2}} + -2 \cdot \frac{b\_2}{a} \]
                3. lower-fma.f64N/A

                  \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{c}{b\_2}, \frac{1}{2}, -2 \cdot \frac{b\_2}{a}\right)} \]
                4. lower-/.f64N/A

                  \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{c}{b\_2}}, \frac{1}{2}, -2 \cdot \frac{b\_2}{a}\right) \]
                5. *-commutativeN/A

                  \[\leadsto \mathsf{fma}\left(\frac{c}{b\_2}, \frac{1}{2}, \color{blue}{\frac{b\_2}{a} \cdot -2}\right) \]
                6. lower-*.f64N/A

                  \[\leadsto \mathsf{fma}\left(\frac{c}{b\_2}, \frac{1}{2}, \color{blue}{\frac{b\_2}{a} \cdot -2}\right) \]
                7. lower-/.f6470.8

                  \[\leadsto \mathsf{fma}\left(\frac{c}{b\_2}, 0.5, \color{blue}{\frac{b\_2}{a}} \cdot -2\right) \]
              8. Applied rewrites70.8%

                \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{c}{b\_2}, 0.5, \frac{b\_2}{a} \cdot -2\right)} \]
              9. Step-by-step derivation
                1. Applied rewrites70.6%

                  \[\leadsto \mathsf{fma}\left(b\_2, \color{blue}{\frac{-2}{a}}, 0.5 \cdot \frac{c}{b\_2}\right) \]
              10. Recombined 2 regimes into one program.
              11. Add Preprocessing

              Alternative 6: 68.0% accurate, 1.7× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b\_2 \leq -5 \cdot 10^{-310}:\\ \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\ \mathbf{else}:\\ \;\;\;\;\frac{-2 \cdot b\_2}{a}\\ \end{array} \end{array} \]
              (FPCore (a b_2 c)
               :precision binary64
               (if (<= b_2 -5e-310) (/ (* -0.5 c) b_2) (/ (* -2.0 b_2) a)))
              double code(double a, double b_2, double c) {
              	double tmp;
              	if (b_2 <= -5e-310) {
              		tmp = (-0.5 * c) / b_2;
              	} else {
              		tmp = (-2.0 * b_2) / a;
              	}
              	return tmp;
              }
              
              real(8) function code(a, b_2, c)
                  real(8), intent (in) :: a
                  real(8), intent (in) :: b_2
                  real(8), intent (in) :: c
                  real(8) :: tmp
                  if (b_2 <= (-5d-310)) then
                      tmp = ((-0.5d0) * c) / b_2
                  else
                      tmp = ((-2.0d0) * b_2) / a
                  end if
                  code = tmp
              end function
              
              public static double code(double a, double b_2, double c) {
              	double tmp;
              	if (b_2 <= -5e-310) {
              		tmp = (-0.5 * c) / b_2;
              	} else {
              		tmp = (-2.0 * b_2) / a;
              	}
              	return tmp;
              }
              
              def code(a, b_2, c):
              	tmp = 0
              	if b_2 <= -5e-310:
              		tmp = (-0.5 * c) / b_2
              	else:
              		tmp = (-2.0 * b_2) / a
              	return tmp
              
              function code(a, b_2, c)
              	tmp = 0.0
              	if (b_2 <= -5e-310)
              		tmp = Float64(Float64(-0.5 * c) / b_2);
              	else
              		tmp = Float64(Float64(-2.0 * b_2) / a);
              	end
              	return tmp
              end
              
              function tmp_2 = code(a, b_2, c)
              	tmp = 0.0;
              	if (b_2 <= -5e-310)
              		tmp = (-0.5 * c) / b_2;
              	else
              		tmp = (-2.0 * b_2) / a;
              	end
              	tmp_2 = tmp;
              end
              
              code[a_, b$95$2_, c_] := If[LessEqual[b$95$2, -5e-310], N[(N[(-0.5 * c), $MachinePrecision] / b$95$2), $MachinePrecision], N[(N[(-2.0 * b$95$2), $MachinePrecision] / a), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;b\_2 \leq -5 \cdot 10^{-310}:\\
              \;\;\;\;\frac{-0.5 \cdot c}{b\_2}\\
              
              \mathbf{else}:\\
              \;\;\;\;\frac{-2 \cdot b\_2}{a}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if b_2 < -4.999999999999985e-310

                1. Initial program 27.3%

                  \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
                2. Add Preprocessing
                3. Taylor expanded in b_2 around -inf

                  \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
                4. Step-by-step derivation
                  1. lower-*.f64N/A

                    \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
                  2. lower-/.f6473.3

                    \[\leadsto -0.5 \cdot \color{blue}{\frac{c}{b\_2}} \]
                5. Applied rewrites73.3%

                  \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b\_2}} \]
                6. Step-by-step derivation
                  1. Applied rewrites73.3%

                    \[\leadsto \frac{-0.5 \cdot c}{\color{blue}{b\_2}} \]

                  if -4.999999999999985e-310 < b_2

                  1. Initial program 72.6%

                    \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
                  2. Add Preprocessing
                  3. Taylor expanded in a around 0

                    \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
                  4. Step-by-step derivation
                    1. lower-*.f6470.2

                      \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
                  5. Applied rewrites70.2%

                    \[\leadsto \frac{\color{blue}{-2 \cdot b\_2}}{a} \]
                7. Recombined 2 regimes into one program.
                8. Add Preprocessing

                Alternative 7: 35.0% accurate, 2.4× speedup?

                \[\begin{array}{l} \\ \frac{-0.5 \cdot c}{b\_2} \end{array} \]
                (FPCore (a b_2 c) :precision binary64 (/ (* -0.5 c) b_2))
                double code(double a, double b_2, double c) {
                	return (-0.5 * c) / b_2;
                }
                
                real(8) function code(a, b_2, c)
                    real(8), intent (in) :: a
                    real(8), intent (in) :: b_2
                    real(8), intent (in) :: c
                    code = ((-0.5d0) * c) / b_2
                end function
                
                public static double code(double a, double b_2, double c) {
                	return (-0.5 * c) / b_2;
                }
                
                def code(a, b_2, c):
                	return (-0.5 * c) / b_2
                
                function code(a, b_2, c)
                	return Float64(Float64(-0.5 * c) / b_2)
                end
                
                function tmp = code(a, b_2, c)
                	tmp = (-0.5 * c) / b_2;
                end
                
                code[a_, b$95$2_, c_] := N[(N[(-0.5 * c), $MachinePrecision] / b$95$2), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \frac{-0.5 \cdot c}{b\_2}
                \end{array}
                
                Derivation
                1. Initial program 49.6%

                  \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
                2. Add Preprocessing
                3. Taylor expanded in b_2 around -inf

                  \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
                4. Step-by-step derivation
                  1. lower-*.f64N/A

                    \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
                  2. lower-/.f6438.3

                    \[\leadsto -0.5 \cdot \color{blue}{\frac{c}{b\_2}} \]
                5. Applied rewrites38.3%

                  \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b\_2}} \]
                6. Step-by-step derivation
                  1. Applied rewrites38.3%

                    \[\leadsto \frac{-0.5 \cdot c}{\color{blue}{b\_2}} \]
                  2. Add Preprocessing

                  Alternative 8: 35.0% accurate, 2.4× speedup?

                  \[\begin{array}{l} \\ -0.5 \cdot \frac{c}{b\_2} \end{array} \]
                  (FPCore (a b_2 c) :precision binary64 (* -0.5 (/ c b_2)))
                  double code(double a, double b_2, double c) {
                  	return -0.5 * (c / b_2);
                  }
                  
                  real(8) function code(a, b_2, c)
                      real(8), intent (in) :: a
                      real(8), intent (in) :: b_2
                      real(8), intent (in) :: c
                      code = (-0.5d0) * (c / b_2)
                  end function
                  
                  public static double code(double a, double b_2, double c) {
                  	return -0.5 * (c / b_2);
                  }
                  
                  def code(a, b_2, c):
                  	return -0.5 * (c / b_2)
                  
                  function code(a, b_2, c)
                  	return Float64(-0.5 * Float64(c / b_2))
                  end
                  
                  function tmp = code(a, b_2, c)
                  	tmp = -0.5 * (c / b_2);
                  end
                  
                  code[a_, b$95$2_, c_] := N[(-0.5 * N[(c / b$95$2), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  -0.5 \cdot \frac{c}{b\_2}
                  \end{array}
                  
                  Derivation
                  1. Initial program 49.6%

                    \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
                  2. Add Preprocessing
                  3. Taylor expanded in b_2 around -inf

                    \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
                  4. Step-by-step derivation
                    1. lower-*.f64N/A

                      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
                    2. lower-/.f6438.3

                      \[\leadsto -0.5 \cdot \color{blue}{\frac{c}{b\_2}} \]
                  5. Applied rewrites38.3%

                    \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b\_2}} \]
                  6. Add Preprocessing

                  Alternative 9: 11.1% accurate, 2.4× speedup?

                  \[\begin{array}{l} \\ c \cdot \frac{0.5}{b\_2} \end{array} \]
                  (FPCore (a b_2 c) :precision binary64 (* c (/ 0.5 b_2)))
                  double code(double a, double b_2, double c) {
                  	return c * (0.5 / b_2);
                  }
                  
                  real(8) function code(a, b_2, c)
                      real(8), intent (in) :: a
                      real(8), intent (in) :: b_2
                      real(8), intent (in) :: c
                      code = c * (0.5d0 / b_2)
                  end function
                  
                  public static double code(double a, double b_2, double c) {
                  	return c * (0.5 / b_2);
                  }
                  
                  def code(a, b_2, c):
                  	return c * (0.5 / b_2)
                  
                  function code(a, b_2, c)
                  	return Float64(c * Float64(0.5 / b_2))
                  end
                  
                  function tmp = code(a, b_2, c)
                  	tmp = c * (0.5 / b_2);
                  end
                  
                  code[a_, b$95$2_, c_] := N[(c * N[(0.5 / b$95$2), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  c \cdot \frac{0.5}{b\_2}
                  \end{array}
                  
                  Derivation
                  1. Initial program 49.6%

                    \[\frac{\left(-b\_2\right) - \sqrt{b\_2 \cdot b\_2 - a \cdot c}}{a} \]
                  2. Add Preprocessing
                  3. Taylor expanded in b_2 around -inf

                    \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
                  4. Step-by-step derivation
                    1. lower-*.f64N/A

                      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b\_2}} \]
                    2. lower-/.f6438.3

                      \[\leadsto -0.5 \cdot \color{blue}{\frac{c}{b\_2}} \]
                  5. Applied rewrites38.3%

                    \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b\_2}} \]
                  6. Taylor expanded in c around 0

                    \[\leadsto \color{blue}{-2 \cdot \frac{b\_2}{a} + \frac{1}{2} \cdot \frac{c}{b\_2}} \]
                  7. Step-by-step derivation
                    1. +-commutativeN/A

                      \[\leadsto \color{blue}{\frac{1}{2} \cdot \frac{c}{b\_2} + -2 \cdot \frac{b\_2}{a}} \]
                    2. *-commutativeN/A

                      \[\leadsto \color{blue}{\frac{c}{b\_2} \cdot \frac{1}{2}} + -2 \cdot \frac{b\_2}{a} \]
                    3. lower-fma.f64N/A

                      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{c}{b\_2}, \frac{1}{2}, -2 \cdot \frac{b\_2}{a}\right)} \]
                    4. lower-/.f64N/A

                      \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{c}{b\_2}}, \frac{1}{2}, -2 \cdot \frac{b\_2}{a}\right) \]
                    5. *-commutativeN/A

                      \[\leadsto \mathsf{fma}\left(\frac{c}{b\_2}, \frac{1}{2}, \color{blue}{\frac{b\_2}{a} \cdot -2}\right) \]
                    6. lower-*.f64N/A

                      \[\leadsto \mathsf{fma}\left(\frac{c}{b\_2}, \frac{1}{2}, \color{blue}{\frac{b\_2}{a} \cdot -2}\right) \]
                    7. lower-/.f6436.0

                      \[\leadsto \mathsf{fma}\left(\frac{c}{b\_2}, 0.5, \color{blue}{\frac{b\_2}{a}} \cdot -2\right) \]
                  8. Applied rewrites36.0%

                    \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{c}{b\_2}, 0.5, \frac{b\_2}{a} \cdot -2\right)} \]
                  9. Taylor expanded in a around inf

                    \[\leadsto \frac{1}{2} \cdot \color{blue}{\frac{c}{b\_2}} \]
                  10. Step-by-step derivation
                    1. Applied rewrites13.4%

                      \[\leadsto \frac{c}{b\_2} \cdot \color{blue}{0.5} \]
                    2. Step-by-step derivation
                      1. Applied rewrites13.4%

                        \[\leadsto c \cdot \frac{0.5}{\color{blue}{b\_2}} \]
                      2. Add Preprocessing

                      Developer Target 1: 99.7% accurate, 0.2× speedup?

                      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{\left|a\right|} \cdot \sqrt{\left|c\right|}\\ t_1 := \begin{array}{l} \mathbf{if}\;\mathsf{copysign}\left(a, c\right) = a:\\ \;\;\;\;\sqrt{\left|b\_2\right| - t\_0} \cdot \sqrt{\left|b\_2\right| + t\_0}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{hypot}\left(b\_2, t\_0\right)\\ \end{array}\\ \mathbf{if}\;b\_2 < 0:\\ \;\;\;\;\frac{c}{t\_1 - b\_2}\\ \mathbf{else}:\\ \;\;\;\;\frac{b\_2 + t\_1}{-a}\\ \end{array} \end{array} \]
                      (FPCore (a b_2 c)
                       :precision binary64
                       (let* ((t_0 (* (sqrt (fabs a)) (sqrt (fabs c))))
                              (t_1
                               (if (== (copysign a c) a)
                                 (* (sqrt (- (fabs b_2) t_0)) (sqrt (+ (fabs b_2) t_0)))
                                 (hypot b_2 t_0))))
                         (if (< b_2 0.0) (/ c (- t_1 b_2)) (/ (+ b_2 t_1) (- a)))))
                      double code(double a, double b_2, double c) {
                      	double t_0 = sqrt(fabs(a)) * sqrt(fabs(c));
                      	double tmp;
                      	if (copysign(a, c) == a) {
                      		tmp = sqrt((fabs(b_2) - t_0)) * sqrt((fabs(b_2) + t_0));
                      	} else {
                      		tmp = hypot(b_2, t_0);
                      	}
                      	double t_1 = tmp;
                      	double tmp_1;
                      	if (b_2 < 0.0) {
                      		tmp_1 = c / (t_1 - b_2);
                      	} else {
                      		tmp_1 = (b_2 + t_1) / -a;
                      	}
                      	return tmp_1;
                      }
                      
                      public static double code(double a, double b_2, double c) {
                      	double t_0 = Math.sqrt(Math.abs(a)) * Math.sqrt(Math.abs(c));
                      	double tmp;
                      	if (Math.copySign(a, c) == a) {
                      		tmp = Math.sqrt((Math.abs(b_2) - t_0)) * Math.sqrt((Math.abs(b_2) + t_0));
                      	} else {
                      		tmp = Math.hypot(b_2, t_0);
                      	}
                      	double t_1 = tmp;
                      	double tmp_1;
                      	if (b_2 < 0.0) {
                      		tmp_1 = c / (t_1 - b_2);
                      	} else {
                      		tmp_1 = (b_2 + t_1) / -a;
                      	}
                      	return tmp_1;
                      }
                      
                      def code(a, b_2, c):
                      	t_0 = math.sqrt(math.fabs(a)) * math.sqrt(math.fabs(c))
                      	tmp = 0
                      	if math.copysign(a, c) == a:
                      		tmp = math.sqrt((math.fabs(b_2) - t_0)) * math.sqrt((math.fabs(b_2) + t_0))
                      	else:
                      		tmp = math.hypot(b_2, t_0)
                      	t_1 = tmp
                      	tmp_1 = 0
                      	if b_2 < 0.0:
                      		tmp_1 = c / (t_1 - b_2)
                      	else:
                      		tmp_1 = (b_2 + t_1) / -a
                      	return tmp_1
                      
                      function code(a, b_2, c)
                      	t_0 = Float64(sqrt(abs(a)) * sqrt(abs(c)))
                      	tmp = 0.0
                      	if (copysign(a, c) == a)
                      		tmp = Float64(sqrt(Float64(abs(b_2) - t_0)) * sqrt(Float64(abs(b_2) + t_0)));
                      	else
                      		tmp = hypot(b_2, t_0);
                      	end
                      	t_1 = tmp
                      	tmp_1 = 0.0
                      	if (b_2 < 0.0)
                      		tmp_1 = Float64(c / Float64(t_1 - b_2));
                      	else
                      		tmp_1 = Float64(Float64(b_2 + t_1) / Float64(-a));
                      	end
                      	return tmp_1
                      end
                      
                      function tmp_3 = code(a, b_2, c)
                      	t_0 = sqrt(abs(a)) * sqrt(abs(c));
                      	tmp = 0.0;
                      	if ((sign(c) * abs(a)) == a)
                      		tmp = sqrt((abs(b_2) - t_0)) * sqrt((abs(b_2) + t_0));
                      	else
                      		tmp = hypot(b_2, t_0);
                      	end
                      	t_1 = tmp;
                      	tmp_2 = 0.0;
                      	if (b_2 < 0.0)
                      		tmp_2 = c / (t_1 - b_2);
                      	else
                      		tmp_2 = (b_2 + t_1) / -a;
                      	end
                      	tmp_3 = tmp_2;
                      end
                      
                      code[a_, b$95$2_, c_] := Block[{t$95$0 = N[(N[Sqrt[N[Abs[a], $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[Abs[c], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = If[Equal[N[With[{TMP1 = Abs[a], TMP2 = Sign[c]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision], a], N[(N[Sqrt[N[(N[Abs[b$95$2], $MachinePrecision] - t$95$0), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(N[Abs[b$95$2], $MachinePrecision] + t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Sqrt[b$95$2 ^ 2 + t$95$0 ^ 2], $MachinePrecision]]}, If[Less[b$95$2, 0.0], N[(c / N[(t$95$1 - b$95$2), $MachinePrecision]), $MachinePrecision], N[(N[(b$95$2 + t$95$1), $MachinePrecision] / (-a)), $MachinePrecision]]]]
                      
                      \begin{array}{l}
                      
                      \\
                      \begin{array}{l}
                      t_0 := \sqrt{\left|a\right|} \cdot \sqrt{\left|c\right|}\\
                      t_1 := \begin{array}{l}
                      \mathbf{if}\;\mathsf{copysign}\left(a, c\right) = a:\\
                      \;\;\;\;\sqrt{\left|b\_2\right| - t\_0} \cdot \sqrt{\left|b\_2\right| + t\_0}\\
                      
                      \mathbf{else}:\\
                      \;\;\;\;\mathsf{hypot}\left(b\_2, t\_0\right)\\
                      
                      
                      \end{array}\\
                      \mathbf{if}\;b\_2 < 0:\\
                      \;\;\;\;\frac{c}{t\_1 - b\_2}\\
                      
                      \mathbf{else}:\\
                      \;\;\;\;\frac{b\_2 + t\_1}{-a}\\
                      
                      
                      \end{array}
                      \end{array}
                      

                      Reproduce

                      ?
                      herbie shell --seed 2024332 
                      (FPCore (a b_2 c)
                        :name "quad2m (problem 3.2.1, negative)"
                        :precision binary64
                        :herbie-expected 10
                      
                        :alt
                        (! :herbie-platform default (let ((sqtD (let ((x (* (sqrt (fabs a)) (sqrt (fabs c))))) (if (== (copysign a c) a) (* (sqrt (- (fabs b_2) x)) (sqrt (+ (fabs b_2) x))) (hypot b_2 x))))) (if (< b_2 0) (/ c (- sqtD b_2)) (/ (+ b_2 sqtD) (- a)))))
                      
                        (/ (- (- b_2) (sqrt (- (* b_2 b_2) (* a c)))) a))