Quotient of sum of exps

Percentage Accurate: 98.9% → 98.6%
Time: 10.3s
Alternatives: 17
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \frac{e^{a}}{e^{a} + e^{b}} \end{array} \]
(FPCore (a b) :precision binary64 (/ (exp a) (+ (exp a) (exp b))))
double code(double a, double b) {
	return exp(a) / (exp(a) + exp(b));
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = exp(a) / (exp(a) + exp(b))
end function
public static double code(double a, double b) {
	return Math.exp(a) / (Math.exp(a) + Math.exp(b));
}
def code(a, b):
	return math.exp(a) / (math.exp(a) + math.exp(b))
function code(a, b)
	return Float64(exp(a) / Float64(exp(a) + exp(b)))
end
function tmp = code(a, b)
	tmp = exp(a) / (exp(a) + exp(b));
end
code[a_, b_] := N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[a], $MachinePrecision] + N[Exp[b], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{e^{a}}{e^{a} + e^{b}}
\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 17 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: 98.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{e^{a}}{e^{a} + e^{b}} \end{array} \]
(FPCore (a b) :precision binary64 (/ (exp a) (+ (exp a) (exp b))))
double code(double a, double b) {
	return exp(a) / (exp(a) + exp(b));
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    code = exp(a) / (exp(a) + exp(b))
end function
public static double code(double a, double b) {
	return Math.exp(a) / (Math.exp(a) + Math.exp(b));
}
def code(a, b):
	return math.exp(a) / (math.exp(a) + math.exp(b))
function code(a, b)
	return Float64(exp(a) / Float64(exp(a) + exp(b)))
end
function tmp = code(a, b)
	tmp = exp(a) / (exp(a) + exp(b));
end
code[a_, b_] := N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[a], $MachinePrecision] + N[Exp[b], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{e^{a}}{e^{a} + e^{b}}
\end{array}

Alternative 1: 98.6% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;e^{a} \leq 0:\\ \;\;\;\;\frac{e^{a}}{1 + 1}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{e^{b} + 1}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= (exp a) 0.0) (/ (exp a) (+ 1.0 1.0)) (/ 1.0 (+ (exp b) 1.0))))
double code(double a, double b) {
	double tmp;
	if (exp(a) <= 0.0) {
		tmp = exp(a) / (1.0 + 1.0);
	} else {
		tmp = 1.0 / (exp(b) + 1.0);
	}
	return tmp;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8) :: tmp
    if (exp(a) <= 0.0d0) then
        tmp = exp(a) / (1.0d0 + 1.0d0)
    else
        tmp = 1.0d0 / (exp(b) + 1.0d0)
    end if
    code = tmp
end function
public static double code(double a, double b) {
	double tmp;
	if (Math.exp(a) <= 0.0) {
		tmp = Math.exp(a) / (1.0 + 1.0);
	} else {
		tmp = 1.0 / (Math.exp(b) + 1.0);
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if math.exp(a) <= 0.0:
		tmp = math.exp(a) / (1.0 + 1.0)
	else:
		tmp = 1.0 / (math.exp(b) + 1.0)
	return tmp
function code(a, b)
	tmp = 0.0
	if (exp(a) <= 0.0)
		tmp = Float64(exp(a) / Float64(1.0 + 1.0));
	else
		tmp = Float64(1.0 / Float64(exp(b) + 1.0));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (exp(a) <= 0.0)
		tmp = exp(a) / (1.0 + 1.0);
	else
		tmp = 1.0 / (exp(b) + 1.0);
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[N[Exp[a], $MachinePrecision], 0.0], N[(N[Exp[a], $MachinePrecision] / N[(1.0 + 1.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[Exp[b], $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;e^{a} \leq 0:\\
\;\;\;\;\frac{e^{a}}{1 + 1}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{e^{b} + 1}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (exp.f64 a) < 0.0

    1. Initial program 98.7%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    2. Add Preprocessing
    3. Taylor expanded in b around 0

      \[\leadsto \frac{e^{a}}{e^{a} + \color{blue}{1}} \]
    4. Step-by-step derivation
      1. Applied rewrites98.7%

        \[\leadsto \frac{e^{a}}{e^{a} + \color{blue}{1}} \]
      2. Taylor expanded in a around 0

        \[\leadsto \frac{e^{a}}{\color{blue}{1} + 1} \]
      3. Step-by-step derivation
        1. Applied rewrites98.7%

          \[\leadsto \frac{e^{a}}{\color{blue}{1} + 1} \]

        if 0.0 < (exp.f64 a)

        1. Initial program 98.3%

          \[\frac{e^{a}}{e^{a} + e^{b}} \]
        2. Add Preprocessing
        3. Taylor expanded in a around 0

          \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
        4. Step-by-step derivation
          1. lower-/.f64N/A

            \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
          2. lower-+.f64N/A

            \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
          3. lower-exp.f6499.0

            \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
        5. Applied rewrites99.0%

          \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
      4. Recombined 2 regimes into one program.
      5. Final simplification98.9%

        \[\leadsto \begin{array}{l} \mathbf{if}\;e^{a} \leq 0:\\ \;\;\;\;\frac{e^{a}}{1 + 1}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{e^{b} + 1}\\ \end{array} \]
      6. Add Preprocessing

      Alternative 2: 98.9% accurate, 1.0× speedup?

      \[\begin{array}{l} \\ \frac{e^{a}}{e^{a} + e^{b}} \end{array} \]
      (FPCore (a b) :precision binary64 (/ (exp a) (+ (exp a) (exp b))))
      double code(double a, double b) {
      	return exp(a) / (exp(a) + exp(b));
      }
      
      real(8) function code(a, b)
          real(8), intent (in) :: a
          real(8), intent (in) :: b
          code = exp(a) / (exp(a) + exp(b))
      end function
      
      public static double code(double a, double b) {
      	return Math.exp(a) / (Math.exp(a) + Math.exp(b));
      }
      
      def code(a, b):
      	return math.exp(a) / (math.exp(a) + math.exp(b))
      
      function code(a, b)
      	return Float64(exp(a) / Float64(exp(a) + exp(b)))
      end
      
      function tmp = code(a, b)
      	tmp = exp(a) / (exp(a) + exp(b));
      end
      
      code[a_, b_] := N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[a], $MachinePrecision] + N[Exp[b], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{e^{a}}{e^{a} + e^{b}}
      \end{array}
      
      Derivation
      1. Initial program 98.4%

        \[\frac{e^{a}}{e^{a} + e^{b}} \]
      2. Add Preprocessing
      3. Add Preprocessing

      Alternative 3: 95.1% accurate, 2.5× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)\\ t_1 := a \cdot t\_0\\ \mathbf{if}\;a \leq -1 \cdot 10^{+103}:\\ \;\;\;\;\frac{1}{a \cdot \left(-0.16666666666666666 \cdot \left(a \cdot a\right)\right)}\\ \mathbf{elif}\;a \leq -2.25 \cdot 10^{+69}:\\ \;\;\;\;\frac{1}{\frac{\mathsf{fma}\left(t\_1, t\_1, -4\right)}{\mathsf{fma}\left(a, t\_0, -2\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{e^{b} + 1}\\ \end{array} \end{array} \]
      (FPCore (a b)
       :precision binary64
       (let* ((t_0 (fma a (fma a -0.16666666666666666 0.5) -1.0)) (t_1 (* a t_0)))
         (if (<= a -1e+103)
           (/ 1.0 (* a (* -0.16666666666666666 (* a a))))
           (if (<= a -2.25e+69)
             (/ 1.0 (/ (fma t_1 t_1 -4.0) (fma a t_0 -2.0)))
             (/ 1.0 (+ (exp b) 1.0))))))
      double code(double a, double b) {
      	double t_0 = fma(a, fma(a, -0.16666666666666666, 0.5), -1.0);
      	double t_1 = a * t_0;
      	double tmp;
      	if (a <= -1e+103) {
      		tmp = 1.0 / (a * (-0.16666666666666666 * (a * a)));
      	} else if (a <= -2.25e+69) {
      		tmp = 1.0 / (fma(t_1, t_1, -4.0) / fma(a, t_0, -2.0));
      	} else {
      		tmp = 1.0 / (exp(b) + 1.0);
      	}
      	return tmp;
      }
      
      function code(a, b)
      	t_0 = fma(a, fma(a, -0.16666666666666666, 0.5), -1.0)
      	t_1 = Float64(a * t_0)
      	tmp = 0.0
      	if (a <= -1e+103)
      		tmp = Float64(1.0 / Float64(a * Float64(-0.16666666666666666 * Float64(a * a))));
      	elseif (a <= -2.25e+69)
      		tmp = Float64(1.0 / Float64(fma(t_1, t_1, -4.0) / fma(a, t_0, -2.0)));
      	else
      		tmp = Float64(1.0 / Float64(exp(b) + 1.0));
      	end
      	return tmp
      end
      
      code[a_, b_] := Block[{t$95$0 = N[(a * N[(a * -0.16666666666666666 + 0.5), $MachinePrecision] + -1.0), $MachinePrecision]}, Block[{t$95$1 = N[(a * t$95$0), $MachinePrecision]}, If[LessEqual[a, -1e+103], N[(1.0 / N[(a * N[(-0.16666666666666666 * N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[a, -2.25e+69], N[(1.0 / N[(N[(t$95$1 * t$95$1 + -4.0), $MachinePrecision] / N[(a * t$95$0 + -2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[Exp[b], $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]]]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)\\
      t_1 := a \cdot t\_0\\
      \mathbf{if}\;a \leq -1 \cdot 10^{+103}:\\
      \;\;\;\;\frac{1}{a \cdot \left(-0.16666666666666666 \cdot \left(a \cdot a\right)\right)}\\
      
      \mathbf{elif}\;a \leq -2.25 \cdot 10^{+69}:\\
      \;\;\;\;\frac{1}{\frac{\mathsf{fma}\left(t\_1, t\_1, -4\right)}{\mathsf{fma}\left(a, t\_0, -2\right)}}\\
      
      \mathbf{else}:\\
      \;\;\;\;\frac{1}{e^{b} + 1}\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if a < -1e103

        1. Initial program 100.0%

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

            \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
          2. clear-numN/A

            \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
          3. lower-/.f64N/A

            \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
          4. div-invN/A

            \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
          5. lower-*.f64N/A

            \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
          6. lift-exp.f64N/A

            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
          7. rec-expN/A

            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
          8. lower-exp.f64N/A

            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
          9. lower-neg.f64100.0

            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
        4. Applied rewrites100.0%

          \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
        5. Taylor expanded in b around 0

          \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
        6. Step-by-step derivation
          1. +-commutativeN/A

            \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
          2. distribute-lft-inN/A

            \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
          3. exp-negN/A

            \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
          4. lft-mult-inverseN/A

            \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
          5. *-rgt-identityN/A

            \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
          6. lower-+.f64N/A

            \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
          7. neg-mul-1N/A

            \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
          8. lower-exp.f64N/A

            \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
          9. neg-mul-1N/A

            \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
          10. lower-neg.f64100.0

            \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
        7. Applied rewrites100.0%

          \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
        8. Taylor expanded in a around 0

          \[\leadsto \frac{1}{2 + \color{blue}{a \cdot \left(a \cdot \left(\frac{1}{2} + \frac{-1}{6} \cdot a\right) - 1\right)}} \]
        9. Step-by-step derivation
          1. Applied rewrites100.0%

            \[\leadsto \frac{1}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)}, 2\right)} \]
          2. Taylor expanded in a around inf

            \[\leadsto \frac{1}{\frac{-1}{6} \cdot {a}^{\color{blue}{3}}} \]
          3. Step-by-step derivation
            1. Applied rewrites100.0%

              \[\leadsto \frac{1}{a \cdot \left(-0.16666666666666666 \cdot \color{blue}{\left(a \cdot a\right)}\right)} \]

            if -1e103 < a < -2.25e69

            1. Initial program 100.0%

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

                \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
              2. clear-numN/A

                \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
              3. lower-/.f64N/A

                \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
              4. div-invN/A

                \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
              5. lower-*.f64N/A

                \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
              6. lift-exp.f64N/A

                \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
              7. rec-expN/A

                \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
              8. lower-exp.f64N/A

                \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
              9. lower-neg.f64100.0

                \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
            4. Applied rewrites100.0%

              \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
            5. Taylor expanded in b around 0

              \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
            6. Step-by-step derivation
              1. +-commutativeN/A

                \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
              2. distribute-lft-inN/A

                \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
              3. exp-negN/A

                \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
              4. lft-mult-inverseN/A

                \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
              5. *-rgt-identityN/A

                \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
              6. lower-+.f64N/A

                \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
              7. neg-mul-1N/A

                \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
              8. lower-exp.f64N/A

                \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
              9. neg-mul-1N/A

                \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
              10. lower-neg.f64100.0

                \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
            7. Applied rewrites100.0%

              \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
            8. Taylor expanded in a around 0

              \[\leadsto \frac{1}{2 + \color{blue}{a \cdot \left(a \cdot \left(\frac{1}{2} + \frac{-1}{6} \cdot a\right) - 1\right)}} \]
            9. Step-by-step derivation
              1. Applied rewrites7.6%

                \[\leadsto \frac{1}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)}, 2\right)} \]
              2. Step-by-step derivation
                1. Applied rewrites100.0%

                  \[\leadsto \frac{1}{\frac{\mathsf{fma}\left(a \cdot \mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right), a \cdot \mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right), -4\right)}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)}, -2\right)}} \]

                if -2.25e69 < a

                1. Initial program 97.9%

                  \[\frac{e^{a}}{e^{a} + e^{b}} \]
                2. Add Preprocessing
                3. Taylor expanded in a around 0

                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                4. Step-by-step derivation
                  1. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                  2. lower-+.f64N/A

                    \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                  3. lower-exp.f6496.6

                    \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                5. Applied rewrites96.6%

                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
              3. Recombined 3 regimes into one program.
              4. Final simplification97.4%

                \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -1 \cdot 10^{+103}:\\ \;\;\;\;\frac{1}{a \cdot \left(-0.16666666666666666 \cdot \left(a \cdot a\right)\right)}\\ \mathbf{elif}\;a \leq -2.25 \cdot 10^{+69}:\\ \;\;\;\;\frac{1}{\frac{\mathsf{fma}\left(a \cdot \mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right), a \cdot \mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right), -4\right)}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right), -2\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{e^{b} + 1}\\ \end{array} \]
              5. Add Preprocessing

              Alternative 4: 89.2% accurate, 2.9× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right)\\ \mathbf{if}\;b \leq -15.5:\\ \;\;\;\;e^{b} + 1\\ \mathbf{elif}\;b \leq 4.4 \cdot 10^{+51}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)}\\ \mathbf{elif}\;b \leq 10^{+103}:\\ \;\;\;\;\frac{1}{\frac{\mathsf{fma}\left(t\_0, t\_0, -4\right)}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right), -2\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{b \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\\ \end{array} \end{array} \]
              (FPCore (a b)
               :precision binary64
               (let* ((t_0 (fma (* b b) (fma b 0.16666666666666666 0.5) b)))
                 (if (<= b -15.5)
                   (+ (exp b) 1.0)
                   (if (<= b 4.4e+51)
                     (/ 1.0 (fma a (fma a (* a -0.16666666666666666) -1.0) 2.0))
                     (if (<= b 1e+103)
                       (/
                        1.0
                        (/
                         (fma t_0 t_0 -4.0)
                         (fma b (fma b (fma b 0.16666666666666666 0.5) 1.0) -2.0)))
                       (/ 1.0 (* b (* b (* b 0.16666666666666666)))))))))
              double code(double a, double b) {
              	double t_0 = fma((b * b), fma(b, 0.16666666666666666, 0.5), b);
              	double tmp;
              	if (b <= -15.5) {
              		tmp = exp(b) + 1.0;
              	} else if (b <= 4.4e+51) {
              		tmp = 1.0 / fma(a, fma(a, (a * -0.16666666666666666), -1.0), 2.0);
              	} else if (b <= 1e+103) {
              		tmp = 1.0 / (fma(t_0, t_0, -4.0) / fma(b, fma(b, fma(b, 0.16666666666666666, 0.5), 1.0), -2.0));
              	} else {
              		tmp = 1.0 / (b * (b * (b * 0.16666666666666666)));
              	}
              	return tmp;
              }
              
              function code(a, b)
              	t_0 = fma(Float64(b * b), fma(b, 0.16666666666666666, 0.5), b)
              	tmp = 0.0
              	if (b <= -15.5)
              		tmp = Float64(exp(b) + 1.0);
              	elseif (b <= 4.4e+51)
              		tmp = Float64(1.0 / fma(a, fma(a, Float64(a * -0.16666666666666666), -1.0), 2.0));
              	elseif (b <= 1e+103)
              		tmp = Float64(1.0 / Float64(fma(t_0, t_0, -4.0) / fma(b, fma(b, fma(b, 0.16666666666666666, 0.5), 1.0), -2.0)));
              	else
              		tmp = Float64(1.0 / Float64(b * Float64(b * Float64(b * 0.16666666666666666))));
              	end
              	return tmp
              end
              
              code[a_, b_] := Block[{t$95$0 = N[(N[(b * b), $MachinePrecision] * N[(b * 0.16666666666666666 + 0.5), $MachinePrecision] + b), $MachinePrecision]}, If[LessEqual[b, -15.5], N[(N[Exp[b], $MachinePrecision] + 1.0), $MachinePrecision], If[LessEqual[b, 4.4e+51], N[(1.0 / N[(a * N[(a * N[(a * -0.16666666666666666), $MachinePrecision] + -1.0), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[b, 1e+103], N[(1.0 / N[(N[(t$95$0 * t$95$0 + -4.0), $MachinePrecision] / N[(b * N[(b * N[(b * 0.16666666666666666 + 0.5), $MachinePrecision] + 1.0), $MachinePrecision] + -2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(b * N[(b * N[(b * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              t_0 := \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right)\\
              \mathbf{if}\;b \leq -15.5:\\
              \;\;\;\;e^{b} + 1\\
              
              \mathbf{elif}\;b \leq 4.4 \cdot 10^{+51}:\\
              \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)}\\
              
              \mathbf{elif}\;b \leq 10^{+103}:\\
              \;\;\;\;\frac{1}{\frac{\mathsf{fma}\left(t\_0, t\_0, -4\right)}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right), -2\right)}}\\
              
              \mathbf{else}:\\
              \;\;\;\;\frac{1}{b \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 4 regimes
              2. if b < -15.5

                1. Initial program 98.1%

                  \[\frac{e^{a}}{e^{a} + e^{b}} \]
                2. Add Preprocessing
                3. Taylor expanded in a around 0

                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                4. Step-by-step derivation
                  1. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                  2. lower-+.f64N/A

                    \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                  3. lower-exp.f64100.0

                    \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                5. Applied rewrites100.0%

                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                6. Applied rewrites100.0%

                  \[\leadsto \color{blue}{e^{b} + 1} \]

                if -15.5 < b < 4.39999999999999984e51

                1. Initial program 97.9%

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

                    \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                  2. clear-numN/A

                    \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                  3. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                  4. div-invN/A

                    \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                  5. lower-*.f64N/A

                    \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                  6. lift-exp.f64N/A

                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                  7. rec-expN/A

                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                  8. lower-exp.f64N/A

                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                  9. lower-neg.f6498.0

                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                4. Applied rewrites98.0%

                  \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                5. Taylor expanded in b around 0

                  \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                6. Step-by-step derivation
                  1. +-commutativeN/A

                    \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                  2. distribute-lft-inN/A

                    \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                  3. exp-negN/A

                    \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                  4. lft-mult-inverseN/A

                    \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                  5. *-rgt-identityN/A

                    \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                  6. lower-+.f64N/A

                    \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                  7. neg-mul-1N/A

                    \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                  8. lower-exp.f64N/A

                    \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                  9. neg-mul-1N/A

                    \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                  10. lower-neg.f6490.8

                    \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                7. Applied rewrites90.8%

                  \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                8. Taylor expanded in a around 0

                  \[\leadsto \frac{1}{2 + \color{blue}{a \cdot \left(a \cdot \left(\frac{1}{2} + \frac{-1}{6} \cdot a\right) - 1\right)}} \]
                9. Step-by-step derivation
                  1. Applied rewrites79.5%

                    \[\leadsto \frac{1}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)}, 2\right)} \]
                  2. Taylor expanded in a around inf

                    \[\leadsto \frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, \frac{-1}{6} \cdot a, -1\right), 2\right)} \]
                  3. Step-by-step derivation
                    1. Applied rewrites79.5%

                      \[\leadsto \frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)} \]

                    if 4.39999999999999984e51 < b < 1e103

                    1. Initial program 100.0%

                      \[\frac{e^{a}}{e^{a} + e^{b}} \]
                    2. Add Preprocessing
                    3. Taylor expanded in a around 0

                      \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                    4. Step-by-step derivation
                      1. lower-/.f64N/A

                        \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                      2. lower-+.f64N/A

                        \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                      3. lower-exp.f64100.0

                        \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                    5. Applied rewrites100.0%

                      \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                    6. Taylor expanded in b around 0

                      \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)}} \]
                    7. Step-by-step derivation
                      1. Applied rewrites7.7%

                        \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, 2\right)} \]
                      2. Step-by-step derivation
                        1. Applied rewrites100.0%

                          \[\leadsto \frac{1}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right), \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right), -4\right)}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, -2\right)}} \]

                        if 1e103 < b

                        1. Initial program 100.0%

                          \[\frac{e^{a}}{e^{a} + e^{b}} \]
                        2. Add Preprocessing
                        3. Taylor expanded in a around 0

                          \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                        4. Step-by-step derivation
                          1. lower-/.f64N/A

                            \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                          2. lower-+.f64N/A

                            \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                          3. lower-exp.f64100.0

                            \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                        5. Applied rewrites100.0%

                          \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                        6. Taylor expanded in b around 0

                          \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)}} \]
                        7. Step-by-step derivation
                          1. Applied rewrites100.0%

                            \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, 2\right)} \]
                          2. Taylor expanded in b around inf

                            \[\leadsto \frac{1}{\frac{1}{6} \cdot {b}^{\color{blue}{3}}} \]
                          3. Step-by-step derivation
                            1. Applied rewrites100.0%

                              \[\leadsto \frac{1}{b \cdot \left(b \cdot \color{blue}{\left(b \cdot 0.16666666666666666\right)}\right)} \]
                          4. Recombined 4 regimes into one program.
                          5. Add Preprocessing

                          Alternative 5: 74.4% accurate, 3.4× speedup?

                          \[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right)\\ \mathbf{if}\;b \leq 4.4 \cdot 10^{+51}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)}\\ \mathbf{elif}\;b \leq 10^{+103}:\\ \;\;\;\;\frac{1}{\frac{\mathsf{fma}\left(t\_0, t\_0, -4\right)}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right), -2\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{b \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\\ \end{array} \end{array} \]
                          (FPCore (a b)
                           :precision binary64
                           (let* ((t_0 (fma (* b b) (fma b 0.16666666666666666 0.5) b)))
                             (if (<= b 4.4e+51)
                               (/ 1.0 (fma a (fma a (* a -0.16666666666666666) -1.0) 2.0))
                               (if (<= b 1e+103)
                                 (/
                                  1.0
                                  (/
                                   (fma t_0 t_0 -4.0)
                                   (fma b (fma b (fma b 0.16666666666666666 0.5) 1.0) -2.0)))
                                 (/ 1.0 (* b (* b (* b 0.16666666666666666))))))))
                          double code(double a, double b) {
                          	double t_0 = fma((b * b), fma(b, 0.16666666666666666, 0.5), b);
                          	double tmp;
                          	if (b <= 4.4e+51) {
                          		tmp = 1.0 / fma(a, fma(a, (a * -0.16666666666666666), -1.0), 2.0);
                          	} else if (b <= 1e+103) {
                          		tmp = 1.0 / (fma(t_0, t_0, -4.0) / fma(b, fma(b, fma(b, 0.16666666666666666, 0.5), 1.0), -2.0));
                          	} else {
                          		tmp = 1.0 / (b * (b * (b * 0.16666666666666666)));
                          	}
                          	return tmp;
                          }
                          
                          function code(a, b)
                          	t_0 = fma(Float64(b * b), fma(b, 0.16666666666666666, 0.5), b)
                          	tmp = 0.0
                          	if (b <= 4.4e+51)
                          		tmp = Float64(1.0 / fma(a, fma(a, Float64(a * -0.16666666666666666), -1.0), 2.0));
                          	elseif (b <= 1e+103)
                          		tmp = Float64(1.0 / Float64(fma(t_0, t_0, -4.0) / fma(b, fma(b, fma(b, 0.16666666666666666, 0.5), 1.0), -2.0)));
                          	else
                          		tmp = Float64(1.0 / Float64(b * Float64(b * Float64(b * 0.16666666666666666))));
                          	end
                          	return tmp
                          end
                          
                          code[a_, b_] := Block[{t$95$0 = N[(N[(b * b), $MachinePrecision] * N[(b * 0.16666666666666666 + 0.5), $MachinePrecision] + b), $MachinePrecision]}, If[LessEqual[b, 4.4e+51], N[(1.0 / N[(a * N[(a * N[(a * -0.16666666666666666), $MachinePrecision] + -1.0), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[b, 1e+103], N[(1.0 / N[(N[(t$95$0 * t$95$0 + -4.0), $MachinePrecision] / N[(b * N[(b * N[(b * 0.16666666666666666 + 0.5), $MachinePrecision] + 1.0), $MachinePrecision] + -2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(b * N[(b * N[(b * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
                          
                          \begin{array}{l}
                          
                          \\
                          \begin{array}{l}
                          t_0 := \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right)\\
                          \mathbf{if}\;b \leq 4.4 \cdot 10^{+51}:\\
                          \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)}\\
                          
                          \mathbf{elif}\;b \leq 10^{+103}:\\
                          \;\;\;\;\frac{1}{\frac{\mathsf{fma}\left(t\_0, t\_0, -4\right)}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right), -2\right)}}\\
                          
                          \mathbf{else}:\\
                          \;\;\;\;\frac{1}{b \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\\
                          
                          
                          \end{array}
                          \end{array}
                          
                          Derivation
                          1. Split input into 3 regimes
                          2. if b < 4.39999999999999984e51

                            1. Initial program 98.0%

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

                                \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                              2. clear-numN/A

                                \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                              3. lower-/.f64N/A

                                \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                              4. div-invN/A

                                \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                              5. lower-*.f64N/A

                                \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                              6. lift-exp.f64N/A

                                \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                              7. rec-expN/A

                                \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                              8. lower-exp.f64N/A

                                \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                              9. lower-neg.f6498.0

                                \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                            4. Applied rewrites98.0%

                              \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                            5. Taylor expanded in b around 0

                              \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                            6. Step-by-step derivation
                              1. +-commutativeN/A

                                \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                              2. distribute-lft-inN/A

                                \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                              3. exp-negN/A

                                \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                              4. lft-mult-inverseN/A

                                \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                              5. *-rgt-identityN/A

                                \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                              6. lower-+.f64N/A

                                \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                              7. neg-mul-1N/A

                                \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                              8. lower-exp.f64N/A

                                \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                              9. neg-mul-1N/A

                                \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                              10. lower-neg.f6472.2

                                \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                            7. Applied rewrites72.2%

                              \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                            8. Taylor expanded in a around 0

                              \[\leadsto \frac{1}{2 + \color{blue}{a \cdot \left(a \cdot \left(\frac{1}{2} + \frac{-1}{6} \cdot a\right) - 1\right)}} \]
                            9. Step-by-step derivation
                              1. Applied rewrites63.8%

                                \[\leadsto \frac{1}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)}, 2\right)} \]
                              2. Taylor expanded in a around inf

                                \[\leadsto \frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, \frac{-1}{6} \cdot a, -1\right), 2\right)} \]
                              3. Step-by-step derivation
                                1. Applied rewrites63.8%

                                  \[\leadsto \frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)} \]

                                if 4.39999999999999984e51 < b < 1e103

                                1. Initial program 100.0%

                                  \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                2. Add Preprocessing
                                3. Taylor expanded in a around 0

                                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                4. Step-by-step derivation
                                  1. lower-/.f64N/A

                                    \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                  2. lower-+.f64N/A

                                    \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                  3. lower-exp.f64100.0

                                    \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                5. Applied rewrites100.0%

                                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                6. Taylor expanded in b around 0

                                  \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)}} \]
                                7. Step-by-step derivation
                                  1. Applied rewrites7.7%

                                    \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, 2\right)} \]
                                  2. Step-by-step derivation
                                    1. Applied rewrites100.0%

                                      \[\leadsto \frac{1}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right), \mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right), -4\right)}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, -2\right)}} \]

                                    if 1e103 < b

                                    1. Initial program 100.0%

                                      \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                    2. Add Preprocessing
                                    3. Taylor expanded in a around 0

                                      \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                    4. Step-by-step derivation
                                      1. lower-/.f64N/A

                                        \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                      2. lower-+.f64N/A

                                        \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                      3. lower-exp.f64100.0

                                        \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                    5. Applied rewrites100.0%

                                      \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                    6. Taylor expanded in b around 0

                                      \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)}} \]
                                    7. Step-by-step derivation
                                      1. Applied rewrites100.0%

                                        \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, 2\right)} \]
                                      2. Taylor expanded in b around inf

                                        \[\leadsto \frac{1}{\frac{1}{6} \cdot {b}^{\color{blue}{3}}} \]
                                      3. Step-by-step derivation
                                        1. Applied rewrites100.0%

                                          \[\leadsto \frac{1}{b \cdot \left(b \cdot \color{blue}{\left(b \cdot 0.16666666666666666\right)}\right)} \]
                                      4. Recombined 3 regimes into one program.
                                      5. Add Preprocessing

                                      Alternative 6: 72.5% accurate, 3.9× speedup?

                                      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 2.9 \cdot 10^{+64}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)}\\ \mathbf{elif}\;b \leq 2 \cdot 10^{+154}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(b, \frac{\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right) \cdot \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), -1\right)}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), -1\right)}, 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{b \cdot \left(b \cdot 0.5\right)}\\ \end{array} \end{array} \]
                                      (FPCore (a b)
                                       :precision binary64
                                       (if (<= b 2.9e+64)
                                         (/ 1.0 (fma a (fma a (* a -0.16666666666666666) -1.0) 2.0))
                                         (if (<= b 2e+154)
                                           (/
                                            1.0
                                            (fma
                                             b
                                             (/
                                              (fma
                                               (* b b)
                                               (* (fma b 0.16666666666666666 0.5) (fma b 0.16666666666666666 0.5))
                                               -1.0)
                                              (fma b (fma b 0.16666666666666666 0.5) -1.0))
                                             2.0))
                                           (/ 1.0 (* b (* b 0.5))))))
                                      double code(double a, double b) {
                                      	double tmp;
                                      	if (b <= 2.9e+64) {
                                      		tmp = 1.0 / fma(a, fma(a, (a * -0.16666666666666666), -1.0), 2.0);
                                      	} else if (b <= 2e+154) {
                                      		tmp = 1.0 / fma(b, (fma((b * b), (fma(b, 0.16666666666666666, 0.5) * fma(b, 0.16666666666666666, 0.5)), -1.0) / fma(b, fma(b, 0.16666666666666666, 0.5), -1.0)), 2.0);
                                      	} else {
                                      		tmp = 1.0 / (b * (b * 0.5));
                                      	}
                                      	return tmp;
                                      }
                                      
                                      function code(a, b)
                                      	tmp = 0.0
                                      	if (b <= 2.9e+64)
                                      		tmp = Float64(1.0 / fma(a, fma(a, Float64(a * -0.16666666666666666), -1.0), 2.0));
                                      	elseif (b <= 2e+154)
                                      		tmp = Float64(1.0 / fma(b, Float64(fma(Float64(b * b), Float64(fma(b, 0.16666666666666666, 0.5) * fma(b, 0.16666666666666666, 0.5)), -1.0) / fma(b, fma(b, 0.16666666666666666, 0.5), -1.0)), 2.0));
                                      	else
                                      		tmp = Float64(1.0 / Float64(b * Float64(b * 0.5)));
                                      	end
                                      	return tmp
                                      end
                                      
                                      code[a_, b_] := If[LessEqual[b, 2.9e+64], N[(1.0 / N[(a * N[(a * N[(a * -0.16666666666666666), $MachinePrecision] + -1.0), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[b, 2e+154], N[(1.0 / N[(b * N[(N[(N[(b * b), $MachinePrecision] * N[(N[(b * 0.16666666666666666 + 0.5), $MachinePrecision] * N[(b * 0.16666666666666666 + 0.5), $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision] / N[(b * N[(b * 0.16666666666666666 + 0.5), $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(b * N[(b * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
                                      
                                      \begin{array}{l}
                                      
                                      \\
                                      \begin{array}{l}
                                      \mathbf{if}\;b \leq 2.9 \cdot 10^{+64}:\\
                                      \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)}\\
                                      
                                      \mathbf{elif}\;b \leq 2 \cdot 10^{+154}:\\
                                      \;\;\;\;\frac{1}{\mathsf{fma}\left(b, \frac{\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right) \cdot \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), -1\right)}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), -1\right)}, 2\right)}\\
                                      
                                      \mathbf{else}:\\
                                      \;\;\;\;\frac{1}{b \cdot \left(b \cdot 0.5\right)}\\
                                      
                                      
                                      \end{array}
                                      \end{array}
                                      
                                      Derivation
                                      1. Split input into 3 regimes
                                      2. if b < 2.89999999999999993e64

                                        1. Initial program 98.0%

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

                                            \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                                          2. clear-numN/A

                                            \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                          3. lower-/.f64N/A

                                            \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                          4. div-invN/A

                                            \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                          5. lower-*.f64N/A

                                            \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                          6. lift-exp.f64N/A

                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                                          7. rec-expN/A

                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                          8. lower-exp.f64N/A

                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                          9. lower-neg.f6498.0

                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                                        4. Applied rewrites98.0%

                                          \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                                        5. Taylor expanded in b around 0

                                          \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                                        6. Step-by-step derivation
                                          1. +-commutativeN/A

                                            \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                                          2. distribute-lft-inN/A

                                            \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                                          3. exp-negN/A

                                            \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                          4. lft-mult-inverseN/A

                                            \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                          5. *-rgt-identityN/A

                                            \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                          6. lower-+.f64N/A

                                            \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                                          7. neg-mul-1N/A

                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                                          8. lower-exp.f64N/A

                                            \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                                          9. neg-mul-1N/A

                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                                          10. lower-neg.f6472.0

                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                                        7. Applied rewrites72.0%

                                          \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                                        8. Taylor expanded in a around 0

                                          \[\leadsto \frac{1}{2 + \color{blue}{a \cdot \left(a \cdot \left(\frac{1}{2} + \frac{-1}{6} \cdot a\right) - 1\right)}} \]
                                        9. Step-by-step derivation
                                          1. Applied rewrites63.7%

                                            \[\leadsto \frac{1}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)}, 2\right)} \]
                                          2. Taylor expanded in a around inf

                                            \[\leadsto \frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, \frac{-1}{6} \cdot a, -1\right), 2\right)} \]
                                          3. Step-by-step derivation
                                            1. Applied rewrites63.7%

                                              \[\leadsto \frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)} \]

                                            if 2.89999999999999993e64 < b < 2.00000000000000007e154

                                            1. Initial program 100.0%

                                              \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                            2. Add Preprocessing
                                            3. Taylor expanded in a around 0

                                              \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                            4. Step-by-step derivation
                                              1. lower-/.f64N/A

                                                \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                              2. lower-+.f64N/A

                                                \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                              3. lower-exp.f64100.0

                                                \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                            5. Applied rewrites100.0%

                                              \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                            6. Taylor expanded in b around 0

                                              \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)}} \]
                                            7. Step-by-step derivation
                                              1. Applied rewrites57.9%

                                                \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, 2\right)} \]
                                              2. Step-by-step derivation
                                                1. Applied rewrites84.3%

                                                  \[\leadsto \frac{1}{\mathsf{fma}\left(b, \frac{\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right) \cdot \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), -1\right)}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, 0.16666666666666666, 0.5\right)}, -1\right)}, 2\right)} \]

                                                if 2.00000000000000007e154 < b

                                                1. Initial program 100.0%

                                                  \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                2. Add Preprocessing
                                                3. Taylor expanded in a around 0

                                                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                4. Step-by-step derivation
                                                  1. lower-/.f64N/A

                                                    \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                  2. lower-+.f64N/A

                                                    \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                  3. lower-exp.f64100.0

                                                    \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                5. Applied rewrites100.0%

                                                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                6. Taylor expanded in b around 0

                                                  \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + \frac{1}{2} \cdot b\right)}} \]
                                                7. Step-by-step derivation
                                                  1. Applied rewrites100.0%

                                                    \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, 0.5, 1\right)}, 2\right)} \]
                                                  2. Taylor expanded in b around inf

                                                    \[\leadsto \frac{1}{\frac{1}{2} \cdot {b}^{\color{blue}{2}}} \]
                                                  3. Step-by-step derivation
                                                    1. Applied rewrites100.0%

                                                      \[\leadsto \frac{1}{b \cdot \left(b \cdot \color{blue}{0.5}\right)} \]
                                                  4. Recombined 3 regimes into one program.
                                                  5. Add Preprocessing

                                                  Alternative 7: 72.7% accurate, 4.7× speedup?

                                                  \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 1.3 \cdot 10^{+75}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)}\\ \mathbf{elif}\;b \leq 5.6 \cdot 10^{+102}:\\ \;\;\;\;\frac{1}{\frac{\left(b \cdot b\right) \cdot \left(b \cdot b\right) - 16}{\mathsf{fma}\left(b, b, 4\right) \cdot \left(b + -2\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{b \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\\ \end{array} \end{array} \]
                                                  (FPCore (a b)
                                                   :precision binary64
                                                   (if (<= b 1.3e+75)
                                                     (/ 1.0 (fma a (fma a (* a -0.16666666666666666) -1.0) 2.0))
                                                     (if (<= b 5.6e+102)
                                                       (/ 1.0 (/ (- (* (* b b) (* b b)) 16.0) (* (fma b b 4.0) (+ b -2.0))))
                                                       (/ 1.0 (* b (* b (* b 0.16666666666666666)))))))
                                                  double code(double a, double b) {
                                                  	double tmp;
                                                  	if (b <= 1.3e+75) {
                                                  		tmp = 1.0 / fma(a, fma(a, (a * -0.16666666666666666), -1.0), 2.0);
                                                  	} else if (b <= 5.6e+102) {
                                                  		tmp = 1.0 / ((((b * b) * (b * b)) - 16.0) / (fma(b, b, 4.0) * (b + -2.0)));
                                                  	} else {
                                                  		tmp = 1.0 / (b * (b * (b * 0.16666666666666666)));
                                                  	}
                                                  	return tmp;
                                                  }
                                                  
                                                  function code(a, b)
                                                  	tmp = 0.0
                                                  	if (b <= 1.3e+75)
                                                  		tmp = Float64(1.0 / fma(a, fma(a, Float64(a * -0.16666666666666666), -1.0), 2.0));
                                                  	elseif (b <= 5.6e+102)
                                                  		tmp = Float64(1.0 / Float64(Float64(Float64(Float64(b * b) * Float64(b * b)) - 16.0) / Float64(fma(b, b, 4.0) * Float64(b + -2.0))));
                                                  	else
                                                  		tmp = Float64(1.0 / Float64(b * Float64(b * Float64(b * 0.16666666666666666))));
                                                  	end
                                                  	return tmp
                                                  end
                                                  
                                                  code[a_, b_] := If[LessEqual[b, 1.3e+75], N[(1.0 / N[(a * N[(a * N[(a * -0.16666666666666666), $MachinePrecision] + -1.0), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[b, 5.6e+102], N[(1.0 / N[(N[(N[(N[(b * b), $MachinePrecision] * N[(b * b), $MachinePrecision]), $MachinePrecision] - 16.0), $MachinePrecision] / N[(N[(b * b + 4.0), $MachinePrecision] * N[(b + -2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(b * N[(b * N[(b * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
                                                  
                                                  \begin{array}{l}
                                                  
                                                  \\
                                                  \begin{array}{l}
                                                  \mathbf{if}\;b \leq 1.3 \cdot 10^{+75}:\\
                                                  \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)}\\
                                                  
                                                  \mathbf{elif}\;b \leq 5.6 \cdot 10^{+102}:\\
                                                  \;\;\;\;\frac{1}{\frac{\left(b \cdot b\right) \cdot \left(b \cdot b\right) - 16}{\mathsf{fma}\left(b, b, 4\right) \cdot \left(b + -2\right)}}\\
                                                  
                                                  \mathbf{else}:\\
                                                  \;\;\;\;\frac{1}{b \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\\
                                                  
                                                  
                                                  \end{array}
                                                  \end{array}
                                                  
                                                  Derivation
                                                  1. Split input into 3 regimes
                                                  2. if b < 1.29999999999999992e75

                                                    1. Initial program 98.0%

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

                                                        \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                                                      2. clear-numN/A

                                                        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                      3. lower-/.f64N/A

                                                        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                      4. div-invN/A

                                                        \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                      5. lower-*.f64N/A

                                                        \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                      6. lift-exp.f64N/A

                                                        \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                                                      7. rec-expN/A

                                                        \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                      8. lower-exp.f64N/A

                                                        \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                      9. lower-neg.f6498.0

                                                        \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                                                    4. Applied rewrites98.0%

                                                      \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                                                    5. Taylor expanded in b around 0

                                                      \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                                                    6. Step-by-step derivation
                                                      1. +-commutativeN/A

                                                        \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                                                      2. distribute-lft-inN/A

                                                        \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                                                      3. exp-negN/A

                                                        \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                      4. lft-mult-inverseN/A

                                                        \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                      5. *-rgt-identityN/A

                                                        \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                      6. lower-+.f64N/A

                                                        \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                                                      7. neg-mul-1N/A

                                                        \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                                                      8. lower-exp.f64N/A

                                                        \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                                                      9. neg-mul-1N/A

                                                        \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                                                      10. lower-neg.f6471.5

                                                        \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                                                    7. Applied rewrites71.5%

                                                      \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                                                    8. Taylor expanded in a around 0

                                                      \[\leadsto \frac{1}{2 + \color{blue}{a \cdot \left(a \cdot \left(\frac{1}{2} + \frac{-1}{6} \cdot a\right) - 1\right)}} \]
                                                    9. Step-by-step derivation
                                                      1. Applied rewrites62.8%

                                                        \[\leadsto \frac{1}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)}, 2\right)} \]
                                                      2. Taylor expanded in a around inf

                                                        \[\leadsto \frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, \frac{-1}{6} \cdot a, -1\right), 2\right)} \]
                                                      3. Step-by-step derivation
                                                        1. Applied rewrites62.8%

                                                          \[\leadsto \frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)} \]

                                                        if 1.29999999999999992e75 < b < 5.60000000000000037e102

                                                        1. Initial program 100.0%

                                                          \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                        2. Add Preprocessing
                                                        3. Taylor expanded in a around 0

                                                          \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                        4. Step-by-step derivation
                                                          1. lower-/.f64N/A

                                                            \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                          2. lower-+.f64N/A

                                                            \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                          3. lower-exp.f64100.0

                                                            \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                        5. Applied rewrites100.0%

                                                          \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                        6. Taylor expanded in b around 0

                                                          \[\leadsto \frac{1}{2 + \color{blue}{b}} \]
                                                        7. Step-by-step derivation
                                                          1. Applied rewrites3.9%

                                                            \[\leadsto \frac{1}{b + \color{blue}{2}} \]
                                                          2. Step-by-step derivation
                                                            1. Applied rewrites88.0%

                                                              \[\leadsto \frac{1}{\frac{\left(\left(b \cdot b\right) \cdot \left(b \cdot b\right) - 16\right) \cdot 1}{\mathsf{fma}\left(b, b, 4\right) \cdot \color{blue}{\left(b + -2\right)}}} \]

                                                            if 5.60000000000000037e102 < b

                                                            1. Initial program 100.0%

                                                              \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                            2. Add Preprocessing
                                                            3. Taylor expanded in a around 0

                                                              \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                            4. Step-by-step derivation
                                                              1. lower-/.f64N/A

                                                                \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                              2. lower-+.f64N/A

                                                                \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                              3. lower-exp.f64100.0

                                                                \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                            5. Applied rewrites100.0%

                                                              \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                            6. Taylor expanded in b around 0

                                                              \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)}} \]
                                                            7. Step-by-step derivation
                                                              1. Applied rewrites100.0%

                                                                \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, 2\right)} \]
                                                              2. Taylor expanded in b around inf

                                                                \[\leadsto \frac{1}{\frac{1}{6} \cdot {b}^{\color{blue}{3}}} \]
                                                              3. Step-by-step derivation
                                                                1. Applied rewrites100.0%

                                                                  \[\leadsto \frac{1}{b \cdot \left(b \cdot \color{blue}{\left(b \cdot 0.16666666666666666\right)}\right)} \]
                                                              4. Recombined 3 regimes into one program.
                                                              5. Final simplification69.6%

                                                                \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 1.3 \cdot 10^{+75}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)}\\ \mathbf{elif}\;b \leq 5.6 \cdot 10^{+102}:\\ \;\;\;\;\frac{1}{\frac{\left(b \cdot b\right) \cdot \left(b \cdot b\right) - 16}{\mathsf{fma}\left(b, b, 4\right) \cdot \left(b + -2\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{b \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\\ \end{array} \]
                                                              6. Add Preprocessing

                                                              Alternative 8: 71.0% accurate, 9.0× speedup?

                                                              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 5.2 \cdot 10^{+100}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right)}\\ \end{array} \end{array} \]
                                                              (FPCore (a b)
                                                               :precision binary64
                                                               (if (<= b 5.2e+100)
                                                                 (/ 1.0 (fma a (fma a (* a -0.16666666666666666) -1.0) 2.0))
                                                                 (/ 1.0 (fma (* b b) (fma b 0.16666666666666666 0.5) b))))
                                                              double code(double a, double b) {
                                                              	double tmp;
                                                              	if (b <= 5.2e+100) {
                                                              		tmp = 1.0 / fma(a, fma(a, (a * -0.16666666666666666), -1.0), 2.0);
                                                              	} else {
                                                              		tmp = 1.0 / fma((b * b), fma(b, 0.16666666666666666, 0.5), b);
                                                              	}
                                                              	return tmp;
                                                              }
                                                              
                                                              function code(a, b)
                                                              	tmp = 0.0
                                                              	if (b <= 5.2e+100)
                                                              		tmp = Float64(1.0 / fma(a, fma(a, Float64(a * -0.16666666666666666), -1.0), 2.0));
                                                              	else
                                                              		tmp = Float64(1.0 / fma(Float64(b * b), fma(b, 0.16666666666666666, 0.5), b));
                                                              	end
                                                              	return tmp
                                                              end
                                                              
                                                              code[a_, b_] := If[LessEqual[b, 5.2e+100], N[(1.0 / N[(a * N[(a * N[(a * -0.16666666666666666), $MachinePrecision] + -1.0), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[(b * b), $MachinePrecision] * N[(b * 0.16666666666666666 + 0.5), $MachinePrecision] + b), $MachinePrecision]), $MachinePrecision]]
                                                              
                                                              \begin{array}{l}
                                                              
                                                              \\
                                                              \begin{array}{l}
                                                              \mathbf{if}\;b \leq 5.2 \cdot 10^{+100}:\\
                                                              \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)}\\
                                                              
                                                              \mathbf{else}:\\
                                                              \;\;\;\;\frac{1}{\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right)}\\
                                                              
                                                              
                                                              \end{array}
                                                              \end{array}
                                                              
                                                              Derivation
                                                              1. Split input into 2 regimes
                                                              2. if b < 5.2000000000000003e100

                                                                1. Initial program 98.1%

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

                                                                    \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                                                                  2. clear-numN/A

                                                                    \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                  3. lower-/.f64N/A

                                                                    \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                  4. div-invN/A

                                                                    \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                  5. lower-*.f64N/A

                                                                    \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                  6. lift-exp.f64N/A

                                                                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                                                                  7. rec-expN/A

                                                                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                  8. lower-exp.f64N/A

                                                                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                  9. lower-neg.f6498.1

                                                                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                                                                4. Applied rewrites98.1%

                                                                  \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                                                                5. Taylor expanded in b around 0

                                                                  \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                                                                6. Step-by-step derivation
                                                                  1. +-commutativeN/A

                                                                    \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                                                                  2. distribute-lft-inN/A

                                                                    \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                                                                  3. exp-negN/A

                                                                    \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                  4. lft-mult-inverseN/A

                                                                    \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                  5. *-rgt-identityN/A

                                                                    \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                  6. lower-+.f64N/A

                                                                    \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                                                                  7. neg-mul-1N/A

                                                                    \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                                                                  8. lower-exp.f64N/A

                                                                    \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                                                                  9. neg-mul-1N/A

                                                                    \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                                                                  10. lower-neg.f6470.5

                                                                    \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                                                                7. Applied rewrites70.5%

                                                                  \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                                                                8. Taylor expanded in a around 0

                                                                  \[\leadsto \frac{1}{2 + \color{blue}{a \cdot \left(a \cdot \left(\frac{1}{2} + \frac{-1}{6} \cdot a\right) - 1\right)}} \]
                                                                9. Step-by-step derivation
                                                                  1. Applied rewrites62.1%

                                                                    \[\leadsto \frac{1}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)}, 2\right)} \]
                                                                  2. Taylor expanded in a around inf

                                                                    \[\leadsto \frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, \frac{-1}{6} \cdot a, -1\right), 2\right)} \]
                                                                  3. Step-by-step derivation
                                                                    1. Applied rewrites62.1%

                                                                      \[\leadsto \frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, a \cdot -0.16666666666666666, -1\right), 2\right)} \]

                                                                    if 5.2000000000000003e100 < b

                                                                    1. Initial program 100.0%

                                                                      \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                                    2. Add Preprocessing
                                                                    3. Taylor expanded in a around 0

                                                                      \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                    4. Step-by-step derivation
                                                                      1. lower-/.f64N/A

                                                                        \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                      2. lower-+.f64N/A

                                                                        \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                                      3. lower-exp.f64100.0

                                                                        \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                                    5. Applied rewrites100.0%

                                                                      \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                    6. Taylor expanded in b around 0

                                                                      \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)}} \]
                                                                    7. Step-by-step derivation
                                                                      1. Applied rewrites95.9%

                                                                        \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, 2\right)} \]
                                                                      2. Taylor expanded in b around inf

                                                                        \[\leadsto \frac{1}{{b}^{3} \cdot \left(\frac{1}{6} + \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{b} + \frac{1}{{b}^{2}}\right)}\right)} \]
                                                                      3. Step-by-step derivation
                                                                        1. Applied rewrites95.9%

                                                                          \[\leadsto \frac{1}{\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, \color{blue}{0.16666666666666666}, 0.5\right), b\right)} \]
                                                                      4. Recombined 2 regimes into one program.
                                                                      5. Add Preprocessing

                                                                      Alternative 9: 70.7% accurate, 9.0× speedup?

                                                                      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 5.2 \cdot 10^{+100}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(a, -0.16666666666666666 \cdot \left(a \cdot a\right), 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right)}\\ \end{array} \end{array} \]
                                                                      (FPCore (a b)
                                                                       :precision binary64
                                                                       (if (<= b 5.2e+100)
                                                                         (/ 1.0 (fma a (* -0.16666666666666666 (* a a)) 2.0))
                                                                         (/ 1.0 (fma (* b b) (fma b 0.16666666666666666 0.5) b))))
                                                                      double code(double a, double b) {
                                                                      	double tmp;
                                                                      	if (b <= 5.2e+100) {
                                                                      		tmp = 1.0 / fma(a, (-0.16666666666666666 * (a * a)), 2.0);
                                                                      	} else {
                                                                      		tmp = 1.0 / fma((b * b), fma(b, 0.16666666666666666, 0.5), b);
                                                                      	}
                                                                      	return tmp;
                                                                      }
                                                                      
                                                                      function code(a, b)
                                                                      	tmp = 0.0
                                                                      	if (b <= 5.2e+100)
                                                                      		tmp = Float64(1.0 / fma(a, Float64(-0.16666666666666666 * Float64(a * a)), 2.0));
                                                                      	else
                                                                      		tmp = Float64(1.0 / fma(Float64(b * b), fma(b, 0.16666666666666666, 0.5), b));
                                                                      	end
                                                                      	return tmp
                                                                      end
                                                                      
                                                                      code[a_, b_] := If[LessEqual[b, 5.2e+100], N[(1.0 / N[(a * N[(-0.16666666666666666 * N[(a * a), $MachinePrecision]), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[(b * b), $MachinePrecision] * N[(b * 0.16666666666666666 + 0.5), $MachinePrecision] + b), $MachinePrecision]), $MachinePrecision]]
                                                                      
                                                                      \begin{array}{l}
                                                                      
                                                                      \\
                                                                      \begin{array}{l}
                                                                      \mathbf{if}\;b \leq 5.2 \cdot 10^{+100}:\\
                                                                      \;\;\;\;\frac{1}{\mathsf{fma}\left(a, -0.16666666666666666 \cdot \left(a \cdot a\right), 2\right)}\\
                                                                      
                                                                      \mathbf{else}:\\
                                                                      \;\;\;\;\frac{1}{\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), b\right)}\\
                                                                      
                                                                      
                                                                      \end{array}
                                                                      \end{array}
                                                                      
                                                                      Derivation
                                                                      1. Split input into 2 regimes
                                                                      2. if b < 5.2000000000000003e100

                                                                        1. Initial program 98.1%

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

                                                                            \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                                                                          2. clear-numN/A

                                                                            \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                          3. lower-/.f64N/A

                                                                            \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                          4. div-invN/A

                                                                            \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                          5. lower-*.f64N/A

                                                                            \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                          6. lift-exp.f64N/A

                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                                                                          7. rec-expN/A

                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                          8. lower-exp.f64N/A

                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                          9. lower-neg.f6498.1

                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                                                                        4. Applied rewrites98.1%

                                                                          \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                                                                        5. Taylor expanded in b around 0

                                                                          \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                                                                        6. Step-by-step derivation
                                                                          1. +-commutativeN/A

                                                                            \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                                                                          2. distribute-lft-inN/A

                                                                            \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                                                                          3. exp-negN/A

                                                                            \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                          4. lft-mult-inverseN/A

                                                                            \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                          5. *-rgt-identityN/A

                                                                            \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                          6. lower-+.f64N/A

                                                                            \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                                                                          7. neg-mul-1N/A

                                                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                                                                          8. lower-exp.f64N/A

                                                                            \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                                                                          9. neg-mul-1N/A

                                                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                                                                          10. lower-neg.f6470.5

                                                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                                                                        7. Applied rewrites70.5%

                                                                          \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                                                                        8. Taylor expanded in a around 0

                                                                          \[\leadsto \frac{1}{2 + \color{blue}{a \cdot \left(a \cdot \left(\frac{1}{2} + \frac{-1}{6} \cdot a\right) - 1\right)}} \]
                                                                        9. Step-by-step derivation
                                                                          1. Applied rewrites62.1%

                                                                            \[\leadsto \frac{1}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)}, 2\right)} \]
                                                                          2. Taylor expanded in a around inf

                                                                            \[\leadsto \frac{1}{\mathsf{fma}\left(a, \frac{-1}{6} \cdot {a}^{\color{blue}{2}}, 2\right)} \]
                                                                          3. Step-by-step derivation
                                                                            1. Applied rewrites62.0%

                                                                              \[\leadsto \frac{1}{\mathsf{fma}\left(a, -0.16666666666666666 \cdot \left(a \cdot \color{blue}{a}\right), 2\right)} \]

                                                                            if 5.2000000000000003e100 < b

                                                                            1. Initial program 100.0%

                                                                              \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                                            2. Add Preprocessing
                                                                            3. Taylor expanded in a around 0

                                                                              \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                            4. Step-by-step derivation
                                                                              1. lower-/.f64N/A

                                                                                \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                              2. lower-+.f64N/A

                                                                                \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                                              3. lower-exp.f64100.0

                                                                                \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                                            5. Applied rewrites100.0%

                                                                              \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                            6. Taylor expanded in b around 0

                                                                              \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)}} \]
                                                                            7. Step-by-step derivation
                                                                              1. Applied rewrites95.9%

                                                                                \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, 2\right)} \]
                                                                              2. Taylor expanded in b around inf

                                                                                \[\leadsto \frac{1}{{b}^{3} \cdot \left(\frac{1}{6} + \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{b} + \frac{1}{{b}^{2}}\right)}\right)} \]
                                                                              3. Step-by-step derivation
                                                                                1. Applied rewrites95.9%

                                                                                  \[\leadsto \frac{1}{\mathsf{fma}\left(b \cdot b, \mathsf{fma}\left(b, \color{blue}{0.16666666666666666}, 0.5\right), b\right)} \]
                                                                              4. Recombined 2 regimes into one program.
                                                                              5. Add Preprocessing

                                                                              Alternative 10: 70.7% accurate, 9.3× speedup?

                                                                              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 5.2 \cdot 10^{+100}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(a, -0.16666666666666666 \cdot \left(a \cdot a\right), 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{b \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\\ \end{array} \end{array} \]
                                                                              (FPCore (a b)
                                                                               :precision binary64
                                                                               (if (<= b 5.2e+100)
                                                                                 (/ 1.0 (fma a (* -0.16666666666666666 (* a a)) 2.0))
                                                                                 (/ 1.0 (* b (* b (* b 0.16666666666666666))))))
                                                                              double code(double a, double b) {
                                                                              	double tmp;
                                                                              	if (b <= 5.2e+100) {
                                                                              		tmp = 1.0 / fma(a, (-0.16666666666666666 * (a * a)), 2.0);
                                                                              	} else {
                                                                              		tmp = 1.0 / (b * (b * (b * 0.16666666666666666)));
                                                                              	}
                                                                              	return tmp;
                                                                              }
                                                                              
                                                                              function code(a, b)
                                                                              	tmp = 0.0
                                                                              	if (b <= 5.2e+100)
                                                                              		tmp = Float64(1.0 / fma(a, Float64(-0.16666666666666666 * Float64(a * a)), 2.0));
                                                                              	else
                                                                              		tmp = Float64(1.0 / Float64(b * Float64(b * Float64(b * 0.16666666666666666))));
                                                                              	end
                                                                              	return tmp
                                                                              end
                                                                              
                                                                              code[a_, b_] := If[LessEqual[b, 5.2e+100], N[(1.0 / N[(a * N[(-0.16666666666666666 * N[(a * a), $MachinePrecision]), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(b * N[(b * N[(b * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                                                                              
                                                                              \begin{array}{l}
                                                                              
                                                                              \\
                                                                              \begin{array}{l}
                                                                              \mathbf{if}\;b \leq 5.2 \cdot 10^{+100}:\\
                                                                              \;\;\;\;\frac{1}{\mathsf{fma}\left(a, -0.16666666666666666 \cdot \left(a \cdot a\right), 2\right)}\\
                                                                              
                                                                              \mathbf{else}:\\
                                                                              \;\;\;\;\frac{1}{b \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\\
                                                                              
                                                                              
                                                                              \end{array}
                                                                              \end{array}
                                                                              
                                                                              Derivation
                                                                              1. Split input into 2 regimes
                                                                              2. if b < 5.2000000000000003e100

                                                                                1. Initial program 98.1%

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

                                                                                    \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                                                                                  2. clear-numN/A

                                                                                    \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                  3. lower-/.f64N/A

                                                                                    \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                  4. div-invN/A

                                                                                    \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                  5. lower-*.f64N/A

                                                                                    \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                  6. lift-exp.f64N/A

                                                                                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                                                                                  7. rec-expN/A

                                                                                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                  8. lower-exp.f64N/A

                                                                                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                  9. lower-neg.f6498.1

                                                                                    \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                                                                                4. Applied rewrites98.1%

                                                                                  \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                                                                                5. Taylor expanded in b around 0

                                                                                  \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                                                                                6. Step-by-step derivation
                                                                                  1. +-commutativeN/A

                                                                                    \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                                                                                  2. distribute-lft-inN/A

                                                                                    \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                                                                                  3. exp-negN/A

                                                                                    \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                  4. lft-mult-inverseN/A

                                                                                    \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                  5. *-rgt-identityN/A

                                                                                    \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                  6. lower-+.f64N/A

                                                                                    \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                  7. neg-mul-1N/A

                                                                                    \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                                                                                  8. lower-exp.f64N/A

                                                                                    \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                                                                                  9. neg-mul-1N/A

                                                                                    \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                                                                                  10. lower-neg.f6470.5

                                                                                    \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                                                                                7. Applied rewrites70.5%

                                                                                  \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                                                                                8. Taylor expanded in a around 0

                                                                                  \[\leadsto \frac{1}{2 + \color{blue}{a \cdot \left(a \cdot \left(\frac{1}{2} + \frac{-1}{6} \cdot a\right) - 1\right)}} \]
                                                                                9. Step-by-step derivation
                                                                                  1. Applied rewrites62.1%

                                                                                    \[\leadsto \frac{1}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, -0.16666666666666666, 0.5\right), -1\right)}, 2\right)} \]
                                                                                  2. Taylor expanded in a around inf

                                                                                    \[\leadsto \frac{1}{\mathsf{fma}\left(a, \frac{-1}{6} \cdot {a}^{\color{blue}{2}}, 2\right)} \]
                                                                                  3. Step-by-step derivation
                                                                                    1. Applied rewrites62.0%

                                                                                      \[\leadsto \frac{1}{\mathsf{fma}\left(a, -0.16666666666666666 \cdot \left(a \cdot \color{blue}{a}\right), 2\right)} \]

                                                                                    if 5.2000000000000003e100 < b

                                                                                    1. Initial program 100.0%

                                                                                      \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                                                    2. Add Preprocessing
                                                                                    3. Taylor expanded in a around 0

                                                                                      \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                    4. Step-by-step derivation
                                                                                      1. lower-/.f64N/A

                                                                                        \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                      2. lower-+.f64N/A

                                                                                        \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                                                      3. lower-exp.f64100.0

                                                                                        \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                                                    5. Applied rewrites100.0%

                                                                                      \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                    6. Taylor expanded in b around 0

                                                                                      \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)}} \]
                                                                                    7. Step-by-step derivation
                                                                                      1. Applied rewrites95.9%

                                                                                        \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, 2\right)} \]
                                                                                      2. Taylor expanded in b around inf

                                                                                        \[\leadsto \frac{1}{\frac{1}{6} \cdot {b}^{\color{blue}{3}}} \]
                                                                                      3. Step-by-step derivation
                                                                                        1. Applied rewrites95.9%

                                                                                          \[\leadsto \frac{1}{b \cdot \left(b \cdot \color{blue}{\left(b \cdot 0.16666666666666666\right)}\right)} \]
                                                                                      4. Recombined 2 regimes into one program.
                                                                                      5. Add Preprocessing

                                                                                      Alternative 11: 68.0% accurate, 9.5× speedup?

                                                                                      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 5 \cdot 10^{+100}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, 0.5, -1\right), 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{b \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\\ \end{array} \end{array} \]
                                                                                      (FPCore (a b)
                                                                                       :precision binary64
                                                                                       (if (<= b 5e+100)
                                                                                         (/ 1.0 (fma a (fma a 0.5 -1.0) 2.0))
                                                                                         (/ 1.0 (* b (* b (* b 0.16666666666666666))))))
                                                                                      double code(double a, double b) {
                                                                                      	double tmp;
                                                                                      	if (b <= 5e+100) {
                                                                                      		tmp = 1.0 / fma(a, fma(a, 0.5, -1.0), 2.0);
                                                                                      	} else {
                                                                                      		tmp = 1.0 / (b * (b * (b * 0.16666666666666666)));
                                                                                      	}
                                                                                      	return tmp;
                                                                                      }
                                                                                      
                                                                                      function code(a, b)
                                                                                      	tmp = 0.0
                                                                                      	if (b <= 5e+100)
                                                                                      		tmp = Float64(1.0 / fma(a, fma(a, 0.5, -1.0), 2.0));
                                                                                      	else
                                                                                      		tmp = Float64(1.0 / Float64(b * Float64(b * Float64(b * 0.16666666666666666))));
                                                                                      	end
                                                                                      	return tmp
                                                                                      end
                                                                                      
                                                                                      code[a_, b_] := If[LessEqual[b, 5e+100], N[(1.0 / N[(a * N[(a * 0.5 + -1.0), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(b * N[(b * N[(b * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                                                                                      
                                                                                      \begin{array}{l}
                                                                                      
                                                                                      \\
                                                                                      \begin{array}{l}
                                                                                      \mathbf{if}\;b \leq 5 \cdot 10^{+100}:\\
                                                                                      \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, 0.5, -1\right), 2\right)}\\
                                                                                      
                                                                                      \mathbf{else}:\\
                                                                                      \;\;\;\;\frac{1}{b \cdot \left(b \cdot \left(b \cdot 0.16666666666666666\right)\right)}\\
                                                                                      
                                                                                      
                                                                                      \end{array}
                                                                                      \end{array}
                                                                                      
                                                                                      Derivation
                                                                                      1. Split input into 2 regimes
                                                                                      2. if b < 4.9999999999999999e100

                                                                                        1. Initial program 98.1%

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

                                                                                            \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                                                                                          2. clear-numN/A

                                                                                            \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                          3. lower-/.f64N/A

                                                                                            \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                          4. div-invN/A

                                                                                            \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                          5. lower-*.f64N/A

                                                                                            \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                          6. lift-exp.f64N/A

                                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                                                                                          7. rec-expN/A

                                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                          8. lower-exp.f64N/A

                                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                          9. lower-neg.f6498.1

                                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                                                                                        4. Applied rewrites98.1%

                                                                                          \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                                                                                        5. Taylor expanded in b around 0

                                                                                          \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                                                                                        6. Step-by-step derivation
                                                                                          1. +-commutativeN/A

                                                                                            \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                                                                                          2. distribute-lft-inN/A

                                                                                            \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                                                                                          3. exp-negN/A

                                                                                            \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                          4. lft-mult-inverseN/A

                                                                                            \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                          5. *-rgt-identityN/A

                                                                                            \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                          6. lower-+.f64N/A

                                                                                            \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                          7. neg-mul-1N/A

                                                                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                                                                                          8. lower-exp.f64N/A

                                                                                            \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                                                                                          9. neg-mul-1N/A

                                                                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                                                                                          10. lower-neg.f6470.5

                                                                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                                                                                        7. Applied rewrites70.5%

                                                                                          \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                                                                                        8. Taylor expanded in a around 0

                                                                                          \[\leadsto \frac{1}{2 + \color{blue}{a \cdot \left(\frac{1}{2} \cdot a - 1\right)}} \]
                                                                                        9. Step-by-step derivation
                                                                                          1. Applied rewrites57.3%

                                                                                            \[\leadsto \frac{1}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, 0.5, -1\right)}, 2\right)} \]

                                                                                          if 4.9999999999999999e100 < b

                                                                                          1. Initial program 100.0%

                                                                                            \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                                                          2. Add Preprocessing
                                                                                          3. Taylor expanded in a around 0

                                                                                            \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                          4. Step-by-step derivation
                                                                                            1. lower-/.f64N/A

                                                                                              \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                            2. lower-+.f64N/A

                                                                                              \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                                                            3. lower-exp.f64100.0

                                                                                              \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                                                          5. Applied rewrites100.0%

                                                                                            \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                          6. Taylor expanded in b around 0

                                                                                            \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)}} \]
                                                                                          7. Step-by-step derivation
                                                                                            1. Applied rewrites95.9%

                                                                                              \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.16666666666666666, 0.5\right), 1\right)}, 2\right)} \]
                                                                                            2. Taylor expanded in b around inf

                                                                                              \[\leadsto \frac{1}{\frac{1}{6} \cdot {b}^{\color{blue}{3}}} \]
                                                                                            3. Step-by-step derivation
                                                                                              1. Applied rewrites95.9%

                                                                                                \[\leadsto \frac{1}{b \cdot \left(b \cdot \color{blue}{\left(b \cdot 0.16666666666666666\right)}\right)} \]
                                                                                            4. Recombined 2 regimes into one program.
                                                                                            5. Add Preprocessing

                                                                                            Alternative 12: 63.4% accurate, 10.5× speedup?

                                                                                            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 5.2 \cdot 10^{+100}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, 0.5, -1\right), 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{b \cdot \left(b \cdot 0.5\right)}\\ \end{array} \end{array} \]
                                                                                            (FPCore (a b)
                                                                                             :precision binary64
                                                                                             (if (<= b 5.2e+100)
                                                                                               (/ 1.0 (fma a (fma a 0.5 -1.0) 2.0))
                                                                                               (/ 1.0 (* b (* b 0.5)))))
                                                                                            double code(double a, double b) {
                                                                                            	double tmp;
                                                                                            	if (b <= 5.2e+100) {
                                                                                            		tmp = 1.0 / fma(a, fma(a, 0.5, -1.0), 2.0);
                                                                                            	} else {
                                                                                            		tmp = 1.0 / (b * (b * 0.5));
                                                                                            	}
                                                                                            	return tmp;
                                                                                            }
                                                                                            
                                                                                            function code(a, b)
                                                                                            	tmp = 0.0
                                                                                            	if (b <= 5.2e+100)
                                                                                            		tmp = Float64(1.0 / fma(a, fma(a, 0.5, -1.0), 2.0));
                                                                                            	else
                                                                                            		tmp = Float64(1.0 / Float64(b * Float64(b * 0.5)));
                                                                                            	end
                                                                                            	return tmp
                                                                                            end
                                                                                            
                                                                                            code[a_, b_] := If[LessEqual[b, 5.2e+100], N[(1.0 / N[(a * N[(a * 0.5 + -1.0), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(b * N[(b * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                                                                                            
                                                                                            \begin{array}{l}
                                                                                            
                                                                                            \\
                                                                                            \begin{array}{l}
                                                                                            \mathbf{if}\;b \leq 5.2 \cdot 10^{+100}:\\
                                                                                            \;\;\;\;\frac{1}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, 0.5, -1\right), 2\right)}\\
                                                                                            
                                                                                            \mathbf{else}:\\
                                                                                            \;\;\;\;\frac{1}{b \cdot \left(b \cdot 0.5\right)}\\
                                                                                            
                                                                                            
                                                                                            \end{array}
                                                                                            \end{array}
                                                                                            
                                                                                            Derivation
                                                                                            1. Split input into 2 regimes
                                                                                            2. if b < 5.2000000000000003e100

                                                                                              1. Initial program 98.1%

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

                                                                                                  \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                                                                                                2. clear-numN/A

                                                                                                  \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                                3. lower-/.f64N/A

                                                                                                  \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                                4. div-invN/A

                                                                                                  \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                                5. lower-*.f64N/A

                                                                                                  \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                                6. lift-exp.f64N/A

                                                                                                  \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                                                                                                7. rec-expN/A

                                                                                                  \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                8. lower-exp.f64N/A

                                                                                                  \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                9. lower-neg.f6498.1

                                                                                                  \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                                                                                              4. Applied rewrites98.1%

                                                                                                \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                                                                                              5. Taylor expanded in b around 0

                                                                                                \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                                                                                              6. Step-by-step derivation
                                                                                                1. +-commutativeN/A

                                                                                                  \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                                                                                                2. distribute-lft-inN/A

                                                                                                  \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                                                                                                3. exp-negN/A

                                                                                                  \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                                4. lft-mult-inverseN/A

                                                                                                  \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                                5. *-rgt-identityN/A

                                                                                                  \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                6. lower-+.f64N/A

                                                                                                  \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                7. neg-mul-1N/A

                                                                                                  \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                                                                                                8. lower-exp.f64N/A

                                                                                                  \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                                                                                                9. neg-mul-1N/A

                                                                                                  \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                                                                                                10. lower-neg.f6470.5

                                                                                                  \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                                                                                              7. Applied rewrites70.5%

                                                                                                \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                                                                                              8. Taylor expanded in a around 0

                                                                                                \[\leadsto \frac{1}{2 + \color{blue}{a \cdot \left(\frac{1}{2} \cdot a - 1\right)}} \]
                                                                                              9. Step-by-step derivation
                                                                                                1. Applied rewrites57.3%

                                                                                                  \[\leadsto \frac{1}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, 0.5, -1\right)}, 2\right)} \]

                                                                                                if 5.2000000000000003e100 < b

                                                                                                1. Initial program 100.0%

                                                                                                  \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                                                                2. Add Preprocessing
                                                                                                3. Taylor expanded in a around 0

                                                                                                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                4. Step-by-step derivation
                                                                                                  1. lower-/.f64N/A

                                                                                                    \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                  2. lower-+.f64N/A

                                                                                                    \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                                                                  3. lower-exp.f64100.0

                                                                                                    \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                                                                5. Applied rewrites100.0%

                                                                                                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                6. Taylor expanded in b around 0

                                                                                                  \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + \frac{1}{2} \cdot b\right)}} \]
                                                                                                7. Step-by-step derivation
                                                                                                  1. Applied rewrites67.8%

                                                                                                    \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, 0.5, 1\right)}, 2\right)} \]
                                                                                                  2. Taylor expanded in b around inf

                                                                                                    \[\leadsto \frac{1}{\frac{1}{2} \cdot {b}^{\color{blue}{2}}} \]
                                                                                                  3. Step-by-step derivation
                                                                                                    1. Applied rewrites67.8%

                                                                                                      \[\leadsto \frac{1}{b \cdot \left(b \cdot \color{blue}{0.5}\right)} \]
                                                                                                  4. Recombined 2 regimes into one program.
                                                                                                  5. Add Preprocessing

                                                                                                  Alternative 13: 53.4% accurate, 10.5× speedup?

                                                                                                  \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 3.2 \cdot 10^{-16}:\\ \;\;\;\;\frac{1}{2 - a}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.5, 1\right), 2\right)}\\ \end{array} \end{array} \]
                                                                                                  (FPCore (a b)
                                                                                                   :precision binary64
                                                                                                   (if (<= b 3.2e-16) (/ 1.0 (- 2.0 a)) (/ 1.0 (fma b (fma b 0.5 1.0) 2.0))))
                                                                                                  double code(double a, double b) {
                                                                                                  	double tmp;
                                                                                                  	if (b <= 3.2e-16) {
                                                                                                  		tmp = 1.0 / (2.0 - a);
                                                                                                  	} else {
                                                                                                  		tmp = 1.0 / fma(b, fma(b, 0.5, 1.0), 2.0);
                                                                                                  	}
                                                                                                  	return tmp;
                                                                                                  }
                                                                                                  
                                                                                                  function code(a, b)
                                                                                                  	tmp = 0.0
                                                                                                  	if (b <= 3.2e-16)
                                                                                                  		tmp = Float64(1.0 / Float64(2.0 - a));
                                                                                                  	else
                                                                                                  		tmp = Float64(1.0 / fma(b, fma(b, 0.5, 1.0), 2.0));
                                                                                                  	end
                                                                                                  	return tmp
                                                                                                  end
                                                                                                  
                                                                                                  code[a_, b_] := If[LessEqual[b, 3.2e-16], N[(1.0 / N[(2.0 - a), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(b * N[(b * 0.5 + 1.0), $MachinePrecision] + 2.0), $MachinePrecision]), $MachinePrecision]]
                                                                                                  
                                                                                                  \begin{array}{l}
                                                                                                  
                                                                                                  \\
                                                                                                  \begin{array}{l}
                                                                                                  \mathbf{if}\;b \leq 3.2 \cdot 10^{-16}:\\
                                                                                                  \;\;\;\;\frac{1}{2 - a}\\
                                                                                                  
                                                                                                  \mathbf{else}:\\
                                                                                                  \;\;\;\;\frac{1}{\mathsf{fma}\left(b, \mathsf{fma}\left(b, 0.5, 1\right), 2\right)}\\
                                                                                                  
                                                                                                  
                                                                                                  \end{array}
                                                                                                  \end{array}
                                                                                                  
                                                                                                  Derivation
                                                                                                  1. Split input into 2 regimes
                                                                                                  2. if b < 3.20000000000000023e-16

                                                                                                    1. Initial program 98.9%

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

                                                                                                        \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                                                                                                      2. clear-numN/A

                                                                                                        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                                      3. lower-/.f64N/A

                                                                                                        \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                                      4. div-invN/A

                                                                                                        \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                                      5. lower-*.f64N/A

                                                                                                        \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                                      6. lift-exp.f64N/A

                                                                                                        \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                                                                                                      7. rec-expN/A

                                                                                                        \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                      8. lower-exp.f64N/A

                                                                                                        \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                      9. lower-neg.f6498.9

                                                                                                        \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                                                                                                    4. Applied rewrites98.9%

                                                                                                      \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                                                                                                    5. Taylor expanded in b around 0

                                                                                                      \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                                                                                                    6. Step-by-step derivation
                                                                                                      1. +-commutativeN/A

                                                                                                        \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                                                                                                      2. distribute-lft-inN/A

                                                                                                        \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                                                                                                      3. exp-negN/A

                                                                                                        \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                                      4. lft-mult-inverseN/A

                                                                                                        \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                                      5. *-rgt-identityN/A

                                                                                                        \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                      6. lower-+.f64N/A

                                                                                                        \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                      7. neg-mul-1N/A

                                                                                                        \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                                                                                                      8. lower-exp.f64N/A

                                                                                                        \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                                                                                                      9. neg-mul-1N/A

                                                                                                        \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                                                                                                      10. lower-neg.f6475.4

                                                                                                        \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                                                                                                    7. Applied rewrites75.4%

                                                                                                      \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                                                                                                    8. Taylor expanded in a around 0

                                                                                                      \[\leadsto \frac{1}{2 + \color{blue}{-1 \cdot a}} \]
                                                                                                    9. Step-by-step derivation
                                                                                                      1. Applied rewrites46.7%

                                                                                                        \[\leadsto \frac{1}{2 - \color{blue}{a}} \]

                                                                                                      if 3.20000000000000023e-16 < b

                                                                                                      1. Initial program 97.3%

                                                                                                        \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                                                                      2. Add Preprocessing
                                                                                                      3. Taylor expanded in a around 0

                                                                                                        \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                      4. Step-by-step derivation
                                                                                                        1. lower-/.f64N/A

                                                                                                          \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                        2. lower-+.f64N/A

                                                                                                          \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                                                                        3. lower-exp.f6497.4

                                                                                                          \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                                                                      5. Applied rewrites97.4%

                                                                                                        \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                      6. Taylor expanded in b around 0

                                                                                                        \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + \frac{1}{2} \cdot b\right)}} \]
                                                                                                      7. Step-by-step derivation
                                                                                                        1. Applied rewrites44.4%

                                                                                                          \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, 0.5, 1\right)}, 2\right)} \]
                                                                                                      8. Recombined 2 regimes into one program.
                                                                                                      9. Add Preprocessing

                                                                                                      Alternative 14: 53.1% accurate, 10.9× speedup?

                                                                                                      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 65000:\\ \;\;\;\;\frac{1}{2 - a}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(b, b \cdot 0.5, b\right)}\\ \end{array} \end{array} \]
                                                                                                      (FPCore (a b)
                                                                                                       :precision binary64
                                                                                                       (if (<= b 65000.0) (/ 1.0 (- 2.0 a)) (/ 1.0 (fma b (* b 0.5) b))))
                                                                                                      double code(double a, double b) {
                                                                                                      	double tmp;
                                                                                                      	if (b <= 65000.0) {
                                                                                                      		tmp = 1.0 / (2.0 - a);
                                                                                                      	} else {
                                                                                                      		tmp = 1.0 / fma(b, (b * 0.5), b);
                                                                                                      	}
                                                                                                      	return tmp;
                                                                                                      }
                                                                                                      
                                                                                                      function code(a, b)
                                                                                                      	tmp = 0.0
                                                                                                      	if (b <= 65000.0)
                                                                                                      		tmp = Float64(1.0 / Float64(2.0 - a));
                                                                                                      	else
                                                                                                      		tmp = Float64(1.0 / fma(b, Float64(b * 0.5), b));
                                                                                                      	end
                                                                                                      	return tmp
                                                                                                      end
                                                                                                      
                                                                                                      code[a_, b_] := If[LessEqual[b, 65000.0], N[(1.0 / N[(2.0 - a), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(b * N[(b * 0.5), $MachinePrecision] + b), $MachinePrecision]), $MachinePrecision]]
                                                                                                      
                                                                                                      \begin{array}{l}
                                                                                                      
                                                                                                      \\
                                                                                                      \begin{array}{l}
                                                                                                      \mathbf{if}\;b \leq 65000:\\
                                                                                                      \;\;\;\;\frac{1}{2 - a}\\
                                                                                                      
                                                                                                      \mathbf{else}:\\
                                                                                                      \;\;\;\;\frac{1}{\mathsf{fma}\left(b, b \cdot 0.5, b\right)}\\
                                                                                                      
                                                                                                      
                                                                                                      \end{array}
                                                                                                      \end{array}
                                                                                                      
                                                                                                      Derivation
                                                                                                      1. Split input into 2 regimes
                                                                                                      2. if b < 65000

                                                                                                        1. Initial program 98.9%

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

                                                                                                            \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                                                                                                          2. clear-numN/A

                                                                                                            \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                                          3. lower-/.f64N/A

                                                                                                            \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                                          4. div-invN/A

                                                                                                            \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                                          5. lower-*.f64N/A

                                                                                                            \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                                          6. lift-exp.f64N/A

                                                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                                                                                                          7. rec-expN/A

                                                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                          8. lower-exp.f64N/A

                                                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                          9. lower-neg.f6498.9

                                                                                                            \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                                                                                                        4. Applied rewrites98.9%

                                                                                                          \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                                                                                                        5. Taylor expanded in b around 0

                                                                                                          \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                                                                                                        6. Step-by-step derivation
                                                                                                          1. +-commutativeN/A

                                                                                                            \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                                                                                                          2. distribute-lft-inN/A

                                                                                                            \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                                                                                                          3. exp-negN/A

                                                                                                            \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                                          4. lft-mult-inverseN/A

                                                                                                            \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                                          5. *-rgt-identityN/A

                                                                                                            \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                          6. lower-+.f64N/A

                                                                                                            \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                          7. neg-mul-1N/A

                                                                                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                                                                                                          8. lower-exp.f64N/A

                                                                                                            \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                                                                                                          9. neg-mul-1N/A

                                                                                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                                                                                                          10. lower-neg.f6475.7

                                                                                                            \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                                                                                                        7. Applied rewrites75.7%

                                                                                                          \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                                                                                                        8. Taylor expanded in a around 0

                                                                                                          \[\leadsto \frac{1}{2 + \color{blue}{-1 \cdot a}} \]
                                                                                                        9. Step-by-step derivation
                                                                                                          1. Applied rewrites46.4%

                                                                                                            \[\leadsto \frac{1}{2 - \color{blue}{a}} \]

                                                                                                          if 65000 < b

                                                                                                          1. Initial program 97.1%

                                                                                                            \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                                                                          2. Add Preprocessing
                                                                                                          3. Taylor expanded in a around 0

                                                                                                            \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                          4. Step-by-step derivation
                                                                                                            1. lower-/.f64N/A

                                                                                                              \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                            2. lower-+.f64N/A

                                                                                                              \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                                                                            3. lower-exp.f64100.0

                                                                                                              \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                                                                          5. Applied rewrites100.0%

                                                                                                            \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                          6. Taylor expanded in b around 0

                                                                                                            \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + \frac{1}{2} \cdot b\right)}} \]
                                                                                                          7. Step-by-step derivation
                                                                                                            1. Applied rewrites43.8%

                                                                                                              \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, 0.5, 1\right)}, 2\right)} \]
                                                                                                            2. Taylor expanded in b around inf

                                                                                                              \[\leadsto \frac{1}{{b}^{2} \cdot \left(\frac{1}{2} + \color{blue}{\frac{1}{b}}\right)} \]
                                                                                                            3. Step-by-step derivation
                                                                                                              1. Applied rewrites43.8%

                                                                                                                \[\leadsto \frac{1}{\mathsf{fma}\left(b, b \cdot \color{blue}{0.5}, b\right)} \]
                                                                                                            4. Recombined 2 regimes into one program.
                                                                                                            5. Add Preprocessing

                                                                                                            Alternative 15: 53.1% accurate, 11.2× speedup?

                                                                                                            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 65000:\\ \;\;\;\;\frac{1}{2 - a}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{b \cdot \left(b \cdot 0.5\right)}\\ \end{array} \end{array} \]
                                                                                                            (FPCore (a b)
                                                                                                             :precision binary64
                                                                                                             (if (<= b 65000.0) (/ 1.0 (- 2.0 a)) (/ 1.0 (* b (* b 0.5)))))
                                                                                                            double code(double a, double b) {
                                                                                                            	double tmp;
                                                                                                            	if (b <= 65000.0) {
                                                                                                            		tmp = 1.0 / (2.0 - a);
                                                                                                            	} else {
                                                                                                            		tmp = 1.0 / (b * (b * 0.5));
                                                                                                            	}
                                                                                                            	return tmp;
                                                                                                            }
                                                                                                            
                                                                                                            real(8) function code(a, b)
                                                                                                                real(8), intent (in) :: a
                                                                                                                real(8), intent (in) :: b
                                                                                                                real(8) :: tmp
                                                                                                                if (b <= 65000.0d0) then
                                                                                                                    tmp = 1.0d0 / (2.0d0 - a)
                                                                                                                else
                                                                                                                    tmp = 1.0d0 / (b * (b * 0.5d0))
                                                                                                                end if
                                                                                                                code = tmp
                                                                                                            end function
                                                                                                            
                                                                                                            public static double code(double a, double b) {
                                                                                                            	double tmp;
                                                                                                            	if (b <= 65000.0) {
                                                                                                            		tmp = 1.0 / (2.0 - a);
                                                                                                            	} else {
                                                                                                            		tmp = 1.0 / (b * (b * 0.5));
                                                                                                            	}
                                                                                                            	return tmp;
                                                                                                            }
                                                                                                            
                                                                                                            def code(a, b):
                                                                                                            	tmp = 0
                                                                                                            	if b <= 65000.0:
                                                                                                            		tmp = 1.0 / (2.0 - a)
                                                                                                            	else:
                                                                                                            		tmp = 1.0 / (b * (b * 0.5))
                                                                                                            	return tmp
                                                                                                            
                                                                                                            function code(a, b)
                                                                                                            	tmp = 0.0
                                                                                                            	if (b <= 65000.0)
                                                                                                            		tmp = Float64(1.0 / Float64(2.0 - a));
                                                                                                            	else
                                                                                                            		tmp = Float64(1.0 / Float64(b * Float64(b * 0.5)));
                                                                                                            	end
                                                                                                            	return tmp
                                                                                                            end
                                                                                                            
                                                                                                            function tmp_2 = code(a, b)
                                                                                                            	tmp = 0.0;
                                                                                                            	if (b <= 65000.0)
                                                                                                            		tmp = 1.0 / (2.0 - a);
                                                                                                            	else
                                                                                                            		tmp = 1.0 / (b * (b * 0.5));
                                                                                                            	end
                                                                                                            	tmp_2 = tmp;
                                                                                                            end
                                                                                                            
                                                                                                            code[a_, b_] := If[LessEqual[b, 65000.0], N[(1.0 / N[(2.0 - a), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(b * N[(b * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                                                                                                            
                                                                                                            \begin{array}{l}
                                                                                                            
                                                                                                            \\
                                                                                                            \begin{array}{l}
                                                                                                            \mathbf{if}\;b \leq 65000:\\
                                                                                                            \;\;\;\;\frac{1}{2 - a}\\
                                                                                                            
                                                                                                            \mathbf{else}:\\
                                                                                                            \;\;\;\;\frac{1}{b \cdot \left(b \cdot 0.5\right)}\\
                                                                                                            
                                                                                                            
                                                                                                            \end{array}
                                                                                                            \end{array}
                                                                                                            
                                                                                                            Derivation
                                                                                                            1. Split input into 2 regimes
                                                                                                            2. if b < 65000

                                                                                                              1. Initial program 98.9%

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

                                                                                                                  \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                                                                                                                2. clear-numN/A

                                                                                                                  \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                                                3. lower-/.f64N/A

                                                                                                                  \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                                                4. div-invN/A

                                                                                                                  \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                                                5. lower-*.f64N/A

                                                                                                                  \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                                                6. lift-exp.f64N/A

                                                                                                                  \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                                                                                                                7. rec-expN/A

                                                                                                                  \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                                8. lower-exp.f64N/A

                                                                                                                  \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                                9. lower-neg.f6498.9

                                                                                                                  \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                                                                                                              4. Applied rewrites98.9%

                                                                                                                \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                                                                                                              5. Taylor expanded in b around 0

                                                                                                                \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                                                                                                              6. Step-by-step derivation
                                                                                                                1. +-commutativeN/A

                                                                                                                  \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                                                                                                                2. distribute-lft-inN/A

                                                                                                                  \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                                                                                                                3. exp-negN/A

                                                                                                                  \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                                                4. lft-mult-inverseN/A

                                                                                                                  \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                                                5. *-rgt-identityN/A

                                                                                                                  \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                                6. lower-+.f64N/A

                                                                                                                  \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                                7. neg-mul-1N/A

                                                                                                                  \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                                                                                                                8. lower-exp.f64N/A

                                                                                                                  \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                                                                                                                9. neg-mul-1N/A

                                                                                                                  \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                                                                                                                10. lower-neg.f6475.7

                                                                                                                  \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                                                                                                              7. Applied rewrites75.7%

                                                                                                                \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                                                                                                              8. Taylor expanded in a around 0

                                                                                                                \[\leadsto \frac{1}{2 + \color{blue}{-1 \cdot a}} \]
                                                                                                              9. Step-by-step derivation
                                                                                                                1. Applied rewrites46.4%

                                                                                                                  \[\leadsto \frac{1}{2 - \color{blue}{a}} \]

                                                                                                                if 65000 < b

                                                                                                                1. Initial program 97.1%

                                                                                                                  \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                                                                                2. Add Preprocessing
                                                                                                                3. Taylor expanded in a around 0

                                                                                                                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                                4. Step-by-step derivation
                                                                                                                  1. lower-/.f64N/A

                                                                                                                    \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                                  2. lower-+.f64N/A

                                                                                                                    \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                                                                                  3. lower-exp.f64100.0

                                                                                                                    \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                                                                                5. Applied rewrites100.0%

                                                                                                                  \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                                6. Taylor expanded in b around 0

                                                                                                                  \[\leadsto \frac{1}{2 + \color{blue}{b \cdot \left(1 + \frac{1}{2} \cdot b\right)}} \]
                                                                                                                7. Step-by-step derivation
                                                                                                                  1. Applied rewrites43.8%

                                                                                                                    \[\leadsto \frac{1}{\mathsf{fma}\left(b, \color{blue}{\mathsf{fma}\left(b, 0.5, 1\right)}, 2\right)} \]
                                                                                                                  2. Taylor expanded in b around inf

                                                                                                                    \[\leadsto \frac{1}{\frac{1}{2} \cdot {b}^{\color{blue}{2}}} \]
                                                                                                                  3. Step-by-step derivation
                                                                                                                    1. Applied rewrites43.8%

                                                                                                                      \[\leadsto \frac{1}{b \cdot \left(b \cdot \color{blue}{0.5}\right)} \]
                                                                                                                  4. Recombined 2 regimes into one program.
                                                                                                                  5. Add Preprocessing

                                                                                                                  Alternative 16: 39.5% accurate, 21.0× speedup?

                                                                                                                  \[\begin{array}{l} \\ \frac{1}{2 - a} \end{array} \]
                                                                                                                  (FPCore (a b) :precision binary64 (/ 1.0 (- 2.0 a)))
                                                                                                                  double code(double a, double b) {
                                                                                                                  	return 1.0 / (2.0 - a);
                                                                                                                  }
                                                                                                                  
                                                                                                                  real(8) function code(a, b)
                                                                                                                      real(8), intent (in) :: a
                                                                                                                      real(8), intent (in) :: b
                                                                                                                      code = 1.0d0 / (2.0d0 - a)
                                                                                                                  end function
                                                                                                                  
                                                                                                                  public static double code(double a, double b) {
                                                                                                                  	return 1.0 / (2.0 - a);
                                                                                                                  }
                                                                                                                  
                                                                                                                  def code(a, b):
                                                                                                                  	return 1.0 / (2.0 - a)
                                                                                                                  
                                                                                                                  function code(a, b)
                                                                                                                  	return Float64(1.0 / Float64(2.0 - a))
                                                                                                                  end
                                                                                                                  
                                                                                                                  function tmp = code(a, b)
                                                                                                                  	tmp = 1.0 / (2.0 - a);
                                                                                                                  end
                                                                                                                  
                                                                                                                  code[a_, b_] := N[(1.0 / N[(2.0 - a), $MachinePrecision]), $MachinePrecision]
                                                                                                                  
                                                                                                                  \begin{array}{l}
                                                                                                                  
                                                                                                                  \\
                                                                                                                  \frac{1}{2 - a}
                                                                                                                  \end{array}
                                                                                                                  
                                                                                                                  Derivation
                                                                                                                  1. Initial program 98.4%

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

                                                                                                                      \[\leadsto \color{blue}{\frac{e^{a}}{e^{a} + e^{b}}} \]
                                                                                                                    2. clear-numN/A

                                                                                                                      \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                                                    3. lower-/.f64N/A

                                                                                                                      \[\leadsto \color{blue}{\frac{1}{\frac{e^{a} + e^{b}}{e^{a}}}} \]
                                                                                                                    4. div-invN/A

                                                                                                                      \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                                                    5. lower-*.f64N/A

                                                                                                                      \[\leadsto \frac{1}{\color{blue}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{e^{a}}}} \]
                                                                                                                    6. lift-exp.f64N/A

                                                                                                                      \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \frac{1}{\color{blue}{e^{a}}}} \]
                                                                                                                    7. rec-expN/A

                                                                                                                      \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                                    8. lower-exp.f64N/A

                                                                                                                      \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                                    9. lower-neg.f6498.4

                                                                                                                      \[\leadsto \frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{\color{blue}{-a}}} \]
                                                                                                                  4. Applied rewrites98.4%

                                                                                                                    \[\leadsto \color{blue}{\frac{1}{\left(e^{a} + e^{b}\right) \cdot e^{-a}}} \]
                                                                                                                  5. Taylor expanded in b around 0

                                                                                                                    \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot \left(1 + e^{a}\right)}} \]
                                                                                                                  6. Step-by-step derivation
                                                                                                                    1. +-commutativeN/A

                                                                                                                      \[\leadsto \frac{1}{e^{\mathsf{neg}\left(a\right)} \cdot \color{blue}{\left(e^{a} + 1\right)}} \]
                                                                                                                    2. distribute-lft-inN/A

                                                                                                                      \[\leadsto \frac{1}{\color{blue}{e^{\mathsf{neg}\left(a\right)} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1}} \]
                                                                                                                    3. exp-negN/A

                                                                                                                      \[\leadsto \frac{1}{\color{blue}{\frac{1}{e^{a}}} \cdot e^{a} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                                                    4. lft-mult-inverseN/A

                                                                                                                      \[\leadsto \frac{1}{\color{blue}{1} + e^{\mathsf{neg}\left(a\right)} \cdot 1} \]
                                                                                                                    5. *-rgt-identityN/A

                                                                                                                      \[\leadsto \frac{1}{1 + \color{blue}{e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                                    6. lower-+.f64N/A

                                                                                                                      \[\leadsto \frac{1}{\color{blue}{1 + e^{\mathsf{neg}\left(a\right)}}} \]
                                                                                                                    7. neg-mul-1N/A

                                                                                                                      \[\leadsto \frac{1}{1 + e^{\color{blue}{-1 \cdot a}}} \]
                                                                                                                    8. lower-exp.f64N/A

                                                                                                                      \[\leadsto \frac{1}{1 + \color{blue}{e^{-1 \cdot a}}} \]
                                                                                                                    9. neg-mul-1N/A

                                                                                                                      \[\leadsto \frac{1}{1 + e^{\color{blue}{\mathsf{neg}\left(a\right)}}} \]
                                                                                                                    10. lower-neg.f6462.9

                                                                                                                      \[\leadsto \frac{1}{1 + e^{\color{blue}{-a}}} \]
                                                                                                                  7. Applied rewrites62.9%

                                                                                                                    \[\leadsto \frac{1}{\color{blue}{1 + e^{-a}}} \]
                                                                                                                  8. Taylor expanded in a around 0

                                                                                                                    \[\leadsto \frac{1}{2 + \color{blue}{-1 \cdot a}} \]
                                                                                                                  9. Step-by-step derivation
                                                                                                                    1. Applied rewrites34.8%

                                                                                                                      \[\leadsto \frac{1}{2 - \color{blue}{a}} \]
                                                                                                                    2. Add Preprocessing

                                                                                                                    Alternative 17: 38.7% accurate, 315.0× speedup?

                                                                                                                    \[\begin{array}{l} \\ 0.5 \end{array} \]
                                                                                                                    (FPCore (a b) :precision binary64 0.5)
                                                                                                                    double code(double a, double b) {
                                                                                                                    	return 0.5;
                                                                                                                    }
                                                                                                                    
                                                                                                                    real(8) function code(a, b)
                                                                                                                        real(8), intent (in) :: a
                                                                                                                        real(8), intent (in) :: b
                                                                                                                        code = 0.5d0
                                                                                                                    end function
                                                                                                                    
                                                                                                                    public static double code(double a, double b) {
                                                                                                                    	return 0.5;
                                                                                                                    }
                                                                                                                    
                                                                                                                    def code(a, b):
                                                                                                                    	return 0.5
                                                                                                                    
                                                                                                                    function code(a, b)
                                                                                                                    	return 0.5
                                                                                                                    end
                                                                                                                    
                                                                                                                    function tmp = code(a, b)
                                                                                                                    	tmp = 0.5;
                                                                                                                    end
                                                                                                                    
                                                                                                                    code[a_, b_] := 0.5
                                                                                                                    
                                                                                                                    \begin{array}{l}
                                                                                                                    
                                                                                                                    \\
                                                                                                                    0.5
                                                                                                                    \end{array}
                                                                                                                    
                                                                                                                    Derivation
                                                                                                                    1. Initial program 98.4%

                                                                                                                      \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                                                                                    2. Add Preprocessing
                                                                                                                    3. Taylor expanded in a around 0

                                                                                                                      \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                                    4. Step-by-step derivation
                                                                                                                      1. lower-/.f64N/A

                                                                                                                        \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                                      2. lower-+.f64N/A

                                                                                                                        \[\leadsto \frac{1}{\color{blue}{1 + e^{b}}} \]
                                                                                                                      3. lower-exp.f6478.5

                                                                                                                        \[\leadsto \frac{1}{1 + \color{blue}{e^{b}}} \]
                                                                                                                    5. Applied rewrites78.5%

                                                                                                                      \[\leadsto \color{blue}{\frac{1}{1 + e^{b}}} \]
                                                                                                                    6. Taylor expanded in b around 0

                                                                                                                      \[\leadsto \frac{1}{2} \]
                                                                                                                    7. Step-by-step derivation
                                                                                                                      1. Applied rewrites34.3%

                                                                                                                        \[\leadsto 0.5 \]
                                                                                                                      2. Add Preprocessing

                                                                                                                      Developer Target 1: 100.0% accurate, 2.7× speedup?

                                                                                                                      \[\begin{array}{l} \\ \frac{1}{1 + e^{b - a}} \end{array} \]
                                                                                                                      (FPCore (a b) :precision binary64 (/ 1.0 (+ 1.0 (exp (- b a)))))
                                                                                                                      double code(double a, double b) {
                                                                                                                      	return 1.0 / (1.0 + exp((b - a)));
                                                                                                                      }
                                                                                                                      
                                                                                                                      real(8) function code(a, b)
                                                                                                                          real(8), intent (in) :: a
                                                                                                                          real(8), intent (in) :: b
                                                                                                                          code = 1.0d0 / (1.0d0 + exp((b - a)))
                                                                                                                      end function
                                                                                                                      
                                                                                                                      public static double code(double a, double b) {
                                                                                                                      	return 1.0 / (1.0 + Math.exp((b - a)));
                                                                                                                      }
                                                                                                                      
                                                                                                                      def code(a, b):
                                                                                                                      	return 1.0 / (1.0 + math.exp((b - a)))
                                                                                                                      
                                                                                                                      function code(a, b)
                                                                                                                      	return Float64(1.0 / Float64(1.0 + exp(Float64(b - a))))
                                                                                                                      end
                                                                                                                      
                                                                                                                      function tmp = code(a, b)
                                                                                                                      	tmp = 1.0 / (1.0 + exp((b - a)));
                                                                                                                      end
                                                                                                                      
                                                                                                                      code[a_, b_] := N[(1.0 / N[(1.0 + N[Exp[N[(b - a), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                                                                                                                      
                                                                                                                      \begin{array}{l}
                                                                                                                      
                                                                                                                      \\
                                                                                                                      \frac{1}{1 + e^{b - a}}
                                                                                                                      \end{array}
                                                                                                                      

                                                                                                                      Reproduce

                                                                                                                      ?
                                                                                                                      herbie shell --seed 2024216 
                                                                                                                      (FPCore (a b)
                                                                                                                        :name "Quotient of sum of exps"
                                                                                                                        :precision binary64
                                                                                                                      
                                                                                                                        :alt
                                                                                                                        (! :herbie-platform default (/ 1 (+ 1 (exp (- b a)))))
                                                                                                                      
                                                                                                                        (/ (exp a) (+ (exp a) (exp b))))