Quotient of sum of exps

Percentage Accurate: 98.9% → 98.9%
Time: 6.1s
Alternatives: 18
Speedup: 1.4×

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 18 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: 98.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;e^{a} \leq 5 \cdot 10^{-129}:\\ \;\;\;\;\frac{e^{a}}{1 + e^{a}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + e^{b}}\\ \end{array} \end{array} \]
(FPCore (a b)
 :precision binary64
 (if (<= (exp a) 5e-129)
   (/ (exp a) (+ 1.0 (exp a)))
   (/ (+ 1.0 a) (+ (+ 1.0 a) (exp b)))))
double code(double a, double b) {
	double tmp;
	if (exp(a) <= 5e-129) {
		tmp = exp(a) / (1.0 + exp(a));
	} else {
		tmp = (1.0 + a) / ((1.0 + a) + exp(b));
	}
	return tmp;
}
real(8) function code(a, b)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8) :: tmp
    if (exp(a) <= 5d-129) then
        tmp = exp(a) / (1.0d0 + exp(a))
    else
        tmp = (1.0d0 + a) / ((1.0d0 + a) + exp(b))
    end if
    code = tmp
end function
public static double code(double a, double b) {
	double tmp;
	if (Math.exp(a) <= 5e-129) {
		tmp = Math.exp(a) / (1.0 + Math.exp(a));
	} else {
		tmp = (1.0 + a) / ((1.0 + a) + Math.exp(b));
	}
	return tmp;
}
def code(a, b):
	tmp = 0
	if math.exp(a) <= 5e-129:
		tmp = math.exp(a) / (1.0 + math.exp(a))
	else:
		tmp = (1.0 + a) / ((1.0 + a) + math.exp(b))
	return tmp
function code(a, b)
	tmp = 0.0
	if (exp(a) <= 5e-129)
		tmp = Float64(exp(a) / Float64(1.0 + exp(a)));
	else
		tmp = Float64(Float64(1.0 + a) / Float64(Float64(1.0 + a) + exp(b)));
	end
	return tmp
end
function tmp_2 = code(a, b)
	tmp = 0.0;
	if (exp(a) <= 5e-129)
		tmp = exp(a) / (1.0 + exp(a));
	else
		tmp = (1.0 + a) / ((1.0 + a) + exp(b));
	end
	tmp_2 = tmp;
end
code[a_, b_] := If[LessEqual[N[Exp[a], $MachinePrecision], 5e-129], N[(N[Exp[a], $MachinePrecision] / N[(1.0 + N[Exp[a], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 + a), $MachinePrecision] / N[(N[(1.0 + a), $MachinePrecision] + N[Exp[b], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;e^{a} \leq 5 \cdot 10^{-129}:\\
\;\;\;\;\frac{e^{a}}{1 + e^{a}}\\

\mathbf{else}:\\
\;\;\;\;\frac{1 + a}{\left(1 + a\right) + e^{b}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (exp.f64 a) < 5.00000000000000027e-129

    1. Initial program 100.0%

      \[\frac{e^{a}}{e^{a} + e^{b}} \]
    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 rewrites100.0%

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

      if 5.00000000000000027e-129 < (exp.f64 a)

      1. Initial program 99.4%

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

        \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
      4. Step-by-step derivation
        1. lower-+.f6499.4

          \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
      5. Applied rewrites99.4%

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

        \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
      7. Step-by-step derivation
        1. lower-+.f6499.6

          \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
      8. Applied rewrites99.6%

        \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
    5. Recombined 2 regimes into one program.
    6. Final simplification99.7%

      \[\leadsto \begin{array}{l} \mathbf{if}\;e^{a} \leq 5 \cdot 10^{-129}:\\ \;\;\;\;\frac{e^{a}}{1 + e^{a}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + e^{b}}\\ \end{array} \]
    7. Add Preprocessing

    Alternative 2: 59.3% accurate, 0.9× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{\mathsf{fma}\left(0.027777777777777776, b \cdot b, -0.25\right)}{-0.5}, b, 1\right), b, 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \end{array} \end{array} \]
    (FPCore (a b)
     :precision binary64
     (if (<= (/ (exp a) (+ (exp b) (exp a))) 0.49999995)
       (/
        1.0
        (fma (fma (/ (fma 0.027777777777777776 (* b b) -0.25) -0.5) b 1.0) b 2.0))
       (/ (+ 1.0 a) (+ (+ 1.0 a) 1.0))))
    double code(double a, double b) {
    	double tmp;
    	if ((exp(a) / (exp(b) + exp(a))) <= 0.49999995) {
    		tmp = 1.0 / fma(fma((fma(0.027777777777777776, (b * b), -0.25) / -0.5), b, 1.0), b, 2.0);
    	} else {
    		tmp = (1.0 + a) / ((1.0 + a) + 1.0);
    	}
    	return tmp;
    }
    
    function code(a, b)
    	tmp = 0.0
    	if (Float64(exp(a) / Float64(exp(b) + exp(a))) <= 0.49999995)
    		tmp = Float64(1.0 / fma(fma(Float64(fma(0.027777777777777776, Float64(b * b), -0.25) / -0.5), b, 1.0), b, 2.0));
    	else
    		tmp = Float64(Float64(1.0 + a) / Float64(Float64(1.0 + a) + 1.0));
    	end
    	return tmp
    end
    
    code[a_, b_] := If[LessEqual[N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[b], $MachinePrecision] + N[Exp[a], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.49999995], N[(1.0 / N[(N[(N[(N[(0.027777777777777776 * N[(b * b), $MachinePrecision] + -0.25), $MachinePrecision] / -0.5), $MachinePrecision] * b + 1.0), $MachinePrecision] * b + 2.0), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 + a), $MachinePrecision] / N[(N[(1.0 + a), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\
    \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{\mathsf{fma}\left(0.027777777777777776, b \cdot b, -0.25\right)}{-0.5}, b, 1\right), b, 2\right)}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (/.f64 (exp.f64 a) (+.f64 (exp.f64 a) (exp.f64 b))) < 0.499999950000000026

      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. +-commutativeN/A

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

          \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
        4. lower-exp.f6462.4

          \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
      5. Applied rewrites62.4%

        \[\leadsto \color{blue}{\frac{1}{e^{b} + 1}} \]
      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 rewrites48.2%

          \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, b, 0.5\right), b, 1\right), \color{blue}{b}, 2\right)} \]
        2. Step-by-step derivation
          1. Applied rewrites48.2%

            \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{\mathsf{fma}\left(0.027777777777777776, b \cdot b, -0.25\right)}{\mathsf{fma}\left(0.16666666666666666, b, -0.5\right)}, b, 1\right), b, 2\right)} \]
          2. Taylor expanded in b around 0

            \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{\mathsf{fma}\left(\frac{1}{36}, b \cdot b, \frac{-1}{4}\right)}{\frac{-1}{2}}, b, 1\right), b, 2\right)} \]
          3. Step-by-step derivation
            1. Applied rewrites49.0%

              \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{\mathsf{fma}\left(0.027777777777777776, b \cdot b, -0.25\right)}{-0.5}, b, 1\right), b, 2\right)} \]

            if 0.499999950000000026 < (/.f64 (exp.f64 a) (+.f64 (exp.f64 a) (exp.f64 b)))

            1. Initial program 99.2%

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

              \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
            4. Step-by-step derivation
              1. lower-+.f6499.2

                \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
            5. Applied rewrites99.2%

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

              \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
            7. Step-by-step derivation
              1. lower-+.f6499.5

                \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
            8. Applied rewrites99.5%

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

              \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
            10. Step-by-step derivation
              1. Applied rewrites68.9%

                \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
            11. Recombined 2 regimes into one program.
            12. Final simplification59.5%

              \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{\mathsf{fma}\left(0.027777777777777776, b \cdot b, -0.25\right)}{-0.5}, b, 1\right), b, 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \end{array} \]
            13. Add Preprocessing

            Alternative 3: 57.6% accurate, 0.9× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.5000905931675143:\\ \;\;\;\;\frac{1 + a}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, b, 0.5\right), b, 1\right), b, 1\right) + \left(1 + a\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \end{array} \end{array} \]
            (FPCore (a b)
             :precision binary64
             (if (<= (/ (exp a) (+ (exp b) (exp a))) 0.5000905931675143)
               (/
                (+ 1.0 a)
                (+ (fma (fma (fma 0.16666666666666666 b 0.5) b 1.0) b 1.0) (+ 1.0 a)))
               (/ (+ 1.0 a) (+ (+ 1.0 a) 1.0))))
            double code(double a, double b) {
            	double tmp;
            	if ((exp(a) / (exp(b) + exp(a))) <= 0.5000905931675143) {
            		tmp = (1.0 + a) / (fma(fma(fma(0.16666666666666666, b, 0.5), b, 1.0), b, 1.0) + (1.0 + a));
            	} else {
            		tmp = (1.0 + a) / ((1.0 + a) + 1.0);
            	}
            	return tmp;
            }
            
            function code(a, b)
            	tmp = 0.0
            	if (Float64(exp(a) / Float64(exp(b) + exp(a))) <= 0.5000905931675143)
            		tmp = Float64(Float64(1.0 + a) / Float64(fma(fma(fma(0.16666666666666666, b, 0.5), b, 1.0), b, 1.0) + Float64(1.0 + a)));
            	else
            		tmp = Float64(Float64(1.0 + a) / Float64(Float64(1.0 + a) + 1.0));
            	end
            	return tmp
            end
            
            code[a_, b_] := If[LessEqual[N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[b], $MachinePrecision] + N[Exp[a], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.5000905931675143], N[(N[(1.0 + a), $MachinePrecision] / N[(N[(N[(N[(0.16666666666666666 * b + 0.5), $MachinePrecision] * b + 1.0), $MachinePrecision] * b + 1.0), $MachinePrecision] + N[(1.0 + a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 + a), $MachinePrecision] / N[(N[(1.0 + a), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.5000905931675143:\\
            \;\;\;\;\frac{1 + a}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, b, 0.5\right), b, 1\right), b, 1\right) + \left(1 + a\right)}\\
            
            \mathbf{else}:\\
            \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if (/.f64 (exp.f64 a) (+.f64 (exp.f64 a) (exp.f64 b))) < 0.500090593167514252

              1. Initial program 100.0%

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

                \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
              4. Step-by-step derivation
                1. lower-+.f6477.5

                  \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
              5. Applied rewrites77.5%

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

                \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
              7. Step-by-step derivation
                1. lower-+.f6477.8

                  \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
              8. Applied rewrites77.8%

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

                \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{\left(1 + b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)\right)}} \]
              10. Step-by-step derivation
                1. +-commutativeN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{\left(b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right) + 1\right)}} \]
                2. *-commutativeN/A

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

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{\mathsf{fma}\left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right), b, 1\right)}} \]
                4. +-commutativeN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\color{blue}{b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right) + 1}, b, 1\right)} \]
                5. *-commutativeN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\color{blue}{\left(\frac{1}{2} + \frac{1}{6} \cdot b\right) \cdot b} + 1, b, 1\right)} \]
                6. metadata-evalN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\left(\color{blue}{\frac{1}{2} \cdot 1} + \frac{1}{6} \cdot b\right) \cdot b + 1, b, 1\right)} \]
                7. lft-mult-inverseN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\left(\frac{1}{2} \cdot \color{blue}{\left(\frac{1}{b} \cdot b\right)} + \frac{1}{6} \cdot b\right) \cdot b + 1, b, 1\right)} \]
                8. associate-*l*N/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\left(\color{blue}{\left(\frac{1}{2} \cdot \frac{1}{b}\right) \cdot b} + \frac{1}{6} \cdot b\right) \cdot b + 1, b, 1\right)} \]
                9. *-commutativeN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\left(\color{blue}{b \cdot \left(\frac{1}{2} \cdot \frac{1}{b}\right)} + \frac{1}{6} \cdot b\right) \cdot b + 1, b, 1\right)} \]
                10. *-commutativeN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\left(b \cdot \left(\frac{1}{2} \cdot \frac{1}{b}\right) + \color{blue}{b \cdot \frac{1}{6}}\right) \cdot b + 1, b, 1\right)} \]
                11. distribute-lft-inN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\color{blue}{\left(b \cdot \left(\frac{1}{2} \cdot \frac{1}{b} + \frac{1}{6}\right)\right)} \cdot b + 1, b, 1\right)} \]
                12. +-commutativeN/A

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

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(b \cdot \left(\frac{1}{6} + \frac{1}{2} \cdot \frac{1}{b}\right), b, 1\right)}, b, 1\right)} \]
                14. distribute-lft-inN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{b \cdot \frac{1}{6} + b \cdot \left(\frac{1}{2} \cdot \frac{1}{b}\right)}, b, 1\right), b, 1\right)} \]
                15. *-commutativeN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{\frac{1}{6} \cdot b} + b \cdot \left(\frac{1}{2} \cdot \frac{1}{b}\right), b, 1\right), b, 1\right)} \]
                16. *-commutativeN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot b + \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{b}\right) \cdot b}, b, 1\right), b, 1\right)} \]
                17. associate-*l*N/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot b + \color{blue}{\frac{1}{2} \cdot \left(\frac{1}{b} \cdot b\right)}, b, 1\right), b, 1\right)} \]
                18. lft-mult-inverseN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot b + \frac{1}{2} \cdot \color{blue}{1}, b, 1\right), b, 1\right)} \]
                19. metadata-evalN/A

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot b + \color{blue}{\frac{1}{2}}, b, 1\right), b, 1\right)} \]
                20. lower-fma.f6469.4

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(0.16666666666666666, b, 0.5\right)}, b, 1\right), b, 1\right)} \]
              11. Applied rewrites69.4%

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

              if 0.500090593167514252 < (/.f64 (exp.f64 a) (+.f64 (exp.f64 a) (exp.f64 b)))

              1. Initial program 98.0%

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

                \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
              4. Step-by-step derivation
                1. lower-+.f6498.1

                  \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
              5. Applied rewrites98.1%

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

                \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
              7. Step-by-step derivation
                1. lower-+.f6498.8

                  \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
              8. Applied rewrites98.8%

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

                \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
              10. Step-by-step derivation
                1. Applied rewrites19.1%

                  \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
              11. Recombined 2 regimes into one program.
              12. Final simplification59.4%

                \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.5000905931675143:\\ \;\;\;\;\frac{1 + a}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, b, 0.5\right), b, 1\right), b, 1\right) + \left(1 + a\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \end{array} \]
              13. Add Preprocessing

              Alternative 4: 57.3% accurate, 0.9× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, b, 0.5\right), b, 1\right), b, 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \end{array} \end{array} \]
              (FPCore (a b)
               :precision binary64
               (if (<= (/ (exp a) (+ (exp b) (exp a))) 0.49999995)
                 (/ 1.0 (fma (fma (fma 0.16666666666666666 b 0.5) b 1.0) b 2.0))
                 (/ (+ 1.0 a) (+ (+ 1.0 a) 1.0))))
              double code(double a, double b) {
              	double tmp;
              	if ((exp(a) / (exp(b) + exp(a))) <= 0.49999995) {
              		tmp = 1.0 / fma(fma(fma(0.16666666666666666, b, 0.5), b, 1.0), b, 2.0);
              	} else {
              		tmp = (1.0 + a) / ((1.0 + a) + 1.0);
              	}
              	return tmp;
              }
              
              function code(a, b)
              	tmp = 0.0
              	if (Float64(exp(a) / Float64(exp(b) + exp(a))) <= 0.49999995)
              		tmp = Float64(1.0 / fma(fma(fma(0.16666666666666666, b, 0.5), b, 1.0), b, 2.0));
              	else
              		tmp = Float64(Float64(1.0 + a) / Float64(Float64(1.0 + a) + 1.0));
              	end
              	return tmp
              end
              
              code[a_, b_] := If[LessEqual[N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[b], $MachinePrecision] + N[Exp[a], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.49999995], N[(1.0 / N[(N[(N[(0.16666666666666666 * b + 0.5), $MachinePrecision] * b + 1.0), $MachinePrecision] * b + 2.0), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 + a), $MachinePrecision] / N[(N[(1.0 + a), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\
              \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, b, 0.5\right), b, 1\right), b, 2\right)}\\
              
              \mathbf{else}:\\
              \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if (/.f64 (exp.f64 a) (+.f64 (exp.f64 a) (exp.f64 b))) < 0.499999950000000026

                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. +-commutativeN/A

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

                    \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
                  4. lower-exp.f6462.4

                    \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
                5. Applied rewrites62.4%

                  \[\leadsto \color{blue}{\frac{1}{e^{b} + 1}} \]
                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 rewrites48.2%

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

                  if 0.499999950000000026 < (/.f64 (exp.f64 a) (+.f64 (exp.f64 a) (exp.f64 b)))

                  1. Initial program 99.2%

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

                    \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                  4. Step-by-step derivation
                    1. lower-+.f6499.2

                      \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                  5. Applied rewrites99.2%

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

                    \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                  7. Step-by-step derivation
                    1. lower-+.f6499.5

                      \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                  8. Applied rewrites99.5%

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

                    \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
                  10. Step-by-step derivation
                    1. Applied rewrites68.9%

                      \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
                  11. Recombined 2 regimes into one program.
                  12. Final simplification59.1%

                    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, b, 0.5\right), b, 1\right), b, 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \end{array} \]
                  13. Add Preprocessing

                  Alternative 5: 57.2% accurate, 0.9× speedup?

                  \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666 \cdot b, b, 1\right), b, 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \end{array} \end{array} \]
                  (FPCore (a b)
                   :precision binary64
                   (if (<= (/ (exp a) (+ (exp b) (exp a))) 0.49999995)
                     (/ 1.0 (fma (fma (* 0.16666666666666666 b) b 1.0) b 2.0))
                     (/ (+ 1.0 a) (+ (+ 1.0 a) 1.0))))
                  double code(double a, double b) {
                  	double tmp;
                  	if ((exp(a) / (exp(b) + exp(a))) <= 0.49999995) {
                  		tmp = 1.0 / fma(fma((0.16666666666666666 * b), b, 1.0), b, 2.0);
                  	} else {
                  		tmp = (1.0 + a) / ((1.0 + a) + 1.0);
                  	}
                  	return tmp;
                  }
                  
                  function code(a, b)
                  	tmp = 0.0
                  	if (Float64(exp(a) / Float64(exp(b) + exp(a))) <= 0.49999995)
                  		tmp = Float64(1.0 / fma(fma(Float64(0.16666666666666666 * b), b, 1.0), b, 2.0));
                  	else
                  		tmp = Float64(Float64(1.0 + a) / Float64(Float64(1.0 + a) + 1.0));
                  	end
                  	return tmp
                  end
                  
                  code[a_, b_] := If[LessEqual[N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[b], $MachinePrecision] + N[Exp[a], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.49999995], N[(1.0 / N[(N[(N[(0.16666666666666666 * b), $MachinePrecision] * b + 1.0), $MachinePrecision] * b + 2.0), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 + a), $MachinePrecision] / N[(N[(1.0 + a), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]]
                  
                  \begin{array}{l}
                  
                  \\
                  \begin{array}{l}
                  \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\
                  \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666 \cdot b, b, 1\right), b, 2\right)}\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\
                  
                  
                  \end{array}
                  \end{array}
                  
                  Derivation
                  1. Split input into 2 regimes
                  2. if (/.f64 (exp.f64 a) (+.f64 (exp.f64 a) (exp.f64 b))) < 0.499999950000000026

                    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. +-commutativeN/A

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

                        \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
                      4. lower-exp.f6462.4

                        \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
                    5. Applied rewrites62.4%

                      \[\leadsto \color{blue}{\frac{1}{e^{b} + 1}} \]
                    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 rewrites48.2%

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

                        \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot b, b, 1\right), b, 2\right)} \]
                      3. Step-by-step derivation
                        1. Applied rewrites47.8%

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

                        if 0.499999950000000026 < (/.f64 (exp.f64 a) (+.f64 (exp.f64 a) (exp.f64 b)))

                        1. Initial program 99.2%

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

                          \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                        4. Step-by-step derivation
                          1. lower-+.f6499.2

                            \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                        5. Applied rewrites99.2%

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

                          \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                        7. Step-by-step derivation
                          1. lower-+.f6499.5

                            \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                        8. Applied rewrites99.5%

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

                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
                        10. Step-by-step derivation
                          1. Applied rewrites68.9%

                            \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
                        11. Recombined 2 regimes into one program.
                        12. Final simplification59.0%

                          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666 \cdot b, b, 1\right), b, 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \end{array} \]
                        13. Add Preprocessing

                        Alternative 6: 53.2% accurate, 0.9× speedup?

                        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(b, 0.5, 1\right), b, 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \end{array} \end{array} \]
                        (FPCore (a b)
                         :precision binary64
                         (if (<= (/ (exp a) (+ (exp b) (exp a))) 0.49999995)
                           (/ 1.0 (fma (fma b 0.5 1.0) b 2.0))
                           (/ (+ 1.0 a) (+ (+ 1.0 a) 1.0))))
                        double code(double a, double b) {
                        	double tmp;
                        	if ((exp(a) / (exp(b) + exp(a))) <= 0.49999995) {
                        		tmp = 1.0 / fma(fma(b, 0.5, 1.0), b, 2.0);
                        	} else {
                        		tmp = (1.0 + a) / ((1.0 + a) + 1.0);
                        	}
                        	return tmp;
                        }
                        
                        function code(a, b)
                        	tmp = 0.0
                        	if (Float64(exp(a) / Float64(exp(b) + exp(a))) <= 0.49999995)
                        		tmp = Float64(1.0 / fma(fma(b, 0.5, 1.0), b, 2.0));
                        	else
                        		tmp = Float64(Float64(1.0 + a) / Float64(Float64(1.0 + a) + 1.0));
                        	end
                        	return tmp
                        end
                        
                        code[a_, b_] := If[LessEqual[N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[b], $MachinePrecision] + N[Exp[a], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.49999995], N[(1.0 / N[(N[(b * 0.5 + 1.0), $MachinePrecision] * b + 2.0), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 + a), $MachinePrecision] / N[(N[(1.0 + a), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]]
                        
                        \begin{array}{l}
                        
                        \\
                        \begin{array}{l}
                        \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\
                        \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(b, 0.5, 1\right), b, 2\right)}\\
                        
                        \mathbf{else}:\\
                        \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\
                        
                        
                        \end{array}
                        \end{array}
                        
                        Derivation
                        1. Split input into 2 regimes
                        2. if (/.f64 (exp.f64 a) (+.f64 (exp.f64 a) (exp.f64 b))) < 0.499999950000000026

                          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. +-commutativeN/A

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

                              \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
                            4. lower-exp.f6462.4

                              \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
                          5. Applied rewrites62.4%

                            \[\leadsto \color{blue}{\frac{1}{e^{b} + 1}} \]
                          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 rewrites34.3%

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

                            if 0.499999950000000026 < (/.f64 (exp.f64 a) (+.f64 (exp.f64 a) (exp.f64 b)))

                            1. Initial program 99.2%

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

                              \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                            4. Step-by-step derivation
                              1. lower-+.f6499.2

                                \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                            5. Applied rewrites99.2%

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

                              \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                            7. Step-by-step derivation
                              1. lower-+.f6499.5

                                \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                            8. Applied rewrites99.5%

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

                              \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
                            10. Step-by-step derivation
                              1. Applied rewrites68.9%

                                \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
                            11. Recombined 2 regimes into one program.
                            12. Final simplification52.6%

                              \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{e^{a}}{e^{b} + e^{a}} \leq 0.49999995:\\ \;\;\;\;\frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(b, 0.5, 1\right), b, 2\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \end{array} \]
                            13. Add Preprocessing

                            Alternative 7: 98.9% accurate, 1.0× speedup?

                            \[\begin{array}{l} \\ \frac{e^{a}}{e^{b} + e^{a}} \end{array} \]
                            (FPCore (a b) :precision binary64 (/ (exp a) (+ (exp b) (exp a))))
                            double code(double a, double b) {
                            	return exp(a) / (exp(b) + exp(a));
                            }
                            
                            real(8) function code(a, b)
                                real(8), intent (in) :: a
                                real(8), intent (in) :: b
                                code = exp(a) / (exp(b) + exp(a))
                            end function
                            
                            public static double code(double a, double b) {
                            	return Math.exp(a) / (Math.exp(b) + Math.exp(a));
                            }
                            
                            def code(a, b):
                            	return math.exp(a) / (math.exp(b) + math.exp(a))
                            
                            function code(a, b)
                            	return Float64(exp(a) / Float64(exp(b) + exp(a)))
                            end
                            
                            function tmp = code(a, b)
                            	tmp = exp(a) / (exp(b) + exp(a));
                            end
                            
                            code[a_, b_] := N[(N[Exp[a], $MachinePrecision] / N[(N[Exp[b], $MachinePrecision] + N[Exp[a], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                            
                            \begin{array}{l}
                            
                            \\
                            \frac{e^{a}}{e^{b} + e^{a}}
                            \end{array}
                            
                            Derivation
                            1. Initial program 99.6%

                              \[\frac{e^{a}}{e^{a} + e^{b}} \]
                            2. Add Preprocessing
                            3. Final simplification99.6%

                              \[\leadsto \frac{e^{a}}{e^{b} + e^{a}} \]
                            4. Add Preprocessing

                            Alternative 8: 98.9% accurate, 1.4× speedup?

                            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;e^{a} \leq 5 \cdot 10^{-129}:\\ \;\;\;\;\frac{e^{a}}{1 + 1}\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + e^{b}}\\ \end{array} \end{array} \]
                            (FPCore (a b)
                             :precision binary64
                             (if (<= (exp a) 5e-129)
                               (/ (exp a) (+ 1.0 1.0))
                               (/ (+ 1.0 a) (+ (+ 1.0 a) (exp b)))))
                            double code(double a, double b) {
                            	double tmp;
                            	if (exp(a) <= 5e-129) {
                            		tmp = exp(a) / (1.0 + 1.0);
                            	} else {
                            		tmp = (1.0 + a) / ((1.0 + a) + exp(b));
                            	}
                            	return tmp;
                            }
                            
                            real(8) function code(a, b)
                                real(8), intent (in) :: a
                                real(8), intent (in) :: b
                                real(8) :: tmp
                                if (exp(a) <= 5d-129) then
                                    tmp = exp(a) / (1.0d0 + 1.0d0)
                                else
                                    tmp = (1.0d0 + a) / ((1.0d0 + a) + exp(b))
                                end if
                                code = tmp
                            end function
                            
                            public static double code(double a, double b) {
                            	double tmp;
                            	if (Math.exp(a) <= 5e-129) {
                            		tmp = Math.exp(a) / (1.0 + 1.0);
                            	} else {
                            		tmp = (1.0 + a) / ((1.0 + a) + Math.exp(b));
                            	}
                            	return tmp;
                            }
                            
                            def code(a, b):
                            	tmp = 0
                            	if math.exp(a) <= 5e-129:
                            		tmp = math.exp(a) / (1.0 + 1.0)
                            	else:
                            		tmp = (1.0 + a) / ((1.0 + a) + math.exp(b))
                            	return tmp
                            
                            function code(a, b)
                            	tmp = 0.0
                            	if (exp(a) <= 5e-129)
                            		tmp = Float64(exp(a) / Float64(1.0 + 1.0));
                            	else
                            		tmp = Float64(Float64(1.0 + a) / Float64(Float64(1.0 + a) + exp(b)));
                            	end
                            	return tmp
                            end
                            
                            function tmp_2 = code(a, b)
                            	tmp = 0.0;
                            	if (exp(a) <= 5e-129)
                            		tmp = exp(a) / (1.0 + 1.0);
                            	else
                            		tmp = (1.0 + a) / ((1.0 + a) + exp(b));
                            	end
                            	tmp_2 = tmp;
                            end
                            
                            code[a_, b_] := If[LessEqual[N[Exp[a], $MachinePrecision], 5e-129], N[(N[Exp[a], $MachinePrecision] / N[(1.0 + 1.0), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 + a), $MachinePrecision] / N[(N[(1.0 + a), $MachinePrecision] + N[Exp[b], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                            
                            \begin{array}{l}
                            
                            \\
                            \begin{array}{l}
                            \mathbf{if}\;e^{a} \leq 5 \cdot 10^{-129}:\\
                            \;\;\;\;\frac{e^{a}}{1 + 1}\\
                            
                            \mathbf{else}:\\
                            \;\;\;\;\frac{1 + a}{\left(1 + a\right) + e^{b}}\\
                            
                            
                            \end{array}
                            \end{array}
                            
                            Derivation
                            1. Split input into 2 regimes
                            2. if (exp.f64 a) < 5.00000000000000027e-129

                              1. Initial program 100.0%

                                \[\frac{e^{a}}{e^{a} + e^{b}} \]
                              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 rewrites100.0%

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

                                  \[\leadsto \frac{e^{a}}{\color{blue}{1} + 1} \]
                                3. Step-by-step derivation
                                  1. Applied rewrites98.8%

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

                                  if 5.00000000000000027e-129 < (exp.f64 a)

                                  1. Initial program 99.4%

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

                                    \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                  4. Step-by-step derivation
                                    1. lower-+.f6499.4

                                      \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                  5. Applied rewrites99.4%

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

                                    \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                  7. Step-by-step derivation
                                    1. lower-+.f6499.6

                                      \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                  8. Applied rewrites99.6%

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

                                Alternative 9: 98.4% accurate, 1.4× speedup?

                                \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;e^{a} \leq 5 \cdot 10^{-129}:\\ \;\;\;\;\frac{e^{a}}{1 + 1}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{1 + e^{b}}\\ \end{array} \end{array} \]
                                (FPCore (a b)
                                 :precision binary64
                                 (if (<= (exp a) 5e-129) (/ (exp a) (+ 1.0 1.0)) (/ 1.0 (+ 1.0 (exp b)))))
                                double code(double a, double b) {
                                	double tmp;
                                	if (exp(a) <= 5e-129) {
                                		tmp = exp(a) / (1.0 + 1.0);
                                	} else {
                                		tmp = 1.0 / (1.0 + exp(b));
                                	}
                                	return tmp;
                                }
                                
                                real(8) function code(a, b)
                                    real(8), intent (in) :: a
                                    real(8), intent (in) :: b
                                    real(8) :: tmp
                                    if (exp(a) <= 5d-129) then
                                        tmp = exp(a) / (1.0d0 + 1.0d0)
                                    else
                                        tmp = 1.0d0 / (1.0d0 + exp(b))
                                    end if
                                    code = tmp
                                end function
                                
                                public static double code(double a, double b) {
                                	double tmp;
                                	if (Math.exp(a) <= 5e-129) {
                                		tmp = Math.exp(a) / (1.0 + 1.0);
                                	} else {
                                		tmp = 1.0 / (1.0 + Math.exp(b));
                                	}
                                	return tmp;
                                }
                                
                                def code(a, b):
                                	tmp = 0
                                	if math.exp(a) <= 5e-129:
                                		tmp = math.exp(a) / (1.0 + 1.0)
                                	else:
                                		tmp = 1.0 / (1.0 + math.exp(b))
                                	return tmp
                                
                                function code(a, b)
                                	tmp = 0.0
                                	if (exp(a) <= 5e-129)
                                		tmp = Float64(exp(a) / Float64(1.0 + 1.0));
                                	else
                                		tmp = Float64(1.0 / Float64(1.0 + exp(b)));
                                	end
                                	return tmp
                                end
                                
                                function tmp_2 = code(a, b)
                                	tmp = 0.0;
                                	if (exp(a) <= 5e-129)
                                		tmp = exp(a) / (1.0 + 1.0);
                                	else
                                		tmp = 1.0 / (1.0 + exp(b));
                                	end
                                	tmp_2 = tmp;
                                end
                                
                                code[a_, b_] := If[LessEqual[N[Exp[a], $MachinePrecision], 5e-129], N[(N[Exp[a], $MachinePrecision] / N[(1.0 + 1.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(1.0 + N[Exp[b], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                                
                                \begin{array}{l}
                                
                                \\
                                \begin{array}{l}
                                \mathbf{if}\;e^{a} \leq 5 \cdot 10^{-129}:\\
                                \;\;\;\;\frac{e^{a}}{1 + 1}\\
                                
                                \mathbf{else}:\\
                                \;\;\;\;\frac{1}{1 + e^{b}}\\
                                
                                
                                \end{array}
                                \end{array}
                                
                                Derivation
                                1. Split input into 2 regimes
                                2. if (exp.f64 a) < 5.00000000000000027e-129

                                  1. Initial program 100.0%

                                    \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                  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 rewrites100.0%

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

                                      \[\leadsto \frac{e^{a}}{\color{blue}{1} + 1} \]
                                    3. Step-by-step derivation
                                      1. Applied rewrites98.8%

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

                                      if 5.00000000000000027e-129 < (exp.f64 a)

                                      1. Initial program 99.4%

                                        \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                      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. +-commutativeN/A

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

                                          \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
                                        4. lower-exp.f6498.9

                                          \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
                                      5. Applied rewrites98.9%

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

                                      \[\leadsto \begin{array}{l} \mathbf{if}\;e^{a} \leq 5 \cdot 10^{-129}:\\ \;\;\;\;\frac{e^{a}}{1 + 1}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{1 + e^{b}}\\ \end{array} \]
                                    6. Add Preprocessing

                                    Alternative 10: 57.3% accurate, 2.4× speedup?

                                    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;e^{b} \leq 2:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\left(0.16666666666666666 \cdot b\right) \cdot \left(b \cdot b\right)}\\ \end{array} \end{array} \]
                                    (FPCore (a b)
                                     :precision binary64
                                     (if (<= (exp b) 2.0)
                                       (/ (+ 1.0 a) (+ (+ 1.0 a) 1.0))
                                       (/ 1.0 (* (* 0.16666666666666666 b) (* b b)))))
                                    double code(double a, double b) {
                                    	double tmp;
                                    	if (exp(b) <= 2.0) {
                                    		tmp = (1.0 + a) / ((1.0 + a) + 1.0);
                                    	} else {
                                    		tmp = 1.0 / ((0.16666666666666666 * b) * (b * b));
                                    	}
                                    	return tmp;
                                    }
                                    
                                    real(8) function code(a, b)
                                        real(8), intent (in) :: a
                                        real(8), intent (in) :: b
                                        real(8) :: tmp
                                        if (exp(b) <= 2.0d0) then
                                            tmp = (1.0d0 + a) / ((1.0d0 + a) + 1.0d0)
                                        else
                                            tmp = 1.0d0 / ((0.16666666666666666d0 * b) * (b * b))
                                        end if
                                        code = tmp
                                    end function
                                    
                                    public static double code(double a, double b) {
                                    	double tmp;
                                    	if (Math.exp(b) <= 2.0) {
                                    		tmp = (1.0 + a) / ((1.0 + a) + 1.0);
                                    	} else {
                                    		tmp = 1.0 / ((0.16666666666666666 * b) * (b * b));
                                    	}
                                    	return tmp;
                                    }
                                    
                                    def code(a, b):
                                    	tmp = 0
                                    	if math.exp(b) <= 2.0:
                                    		tmp = (1.0 + a) / ((1.0 + a) + 1.0)
                                    	else:
                                    		tmp = 1.0 / ((0.16666666666666666 * b) * (b * b))
                                    	return tmp
                                    
                                    function code(a, b)
                                    	tmp = 0.0
                                    	if (exp(b) <= 2.0)
                                    		tmp = Float64(Float64(1.0 + a) / Float64(Float64(1.0 + a) + 1.0));
                                    	else
                                    		tmp = Float64(1.0 / Float64(Float64(0.16666666666666666 * b) * Float64(b * b)));
                                    	end
                                    	return tmp
                                    end
                                    
                                    function tmp_2 = code(a, b)
                                    	tmp = 0.0;
                                    	if (exp(b) <= 2.0)
                                    		tmp = (1.0 + a) / ((1.0 + a) + 1.0);
                                    	else
                                    		tmp = 1.0 / ((0.16666666666666666 * b) * (b * b));
                                    	end
                                    	tmp_2 = tmp;
                                    end
                                    
                                    code[a_, b_] := If[LessEqual[N[Exp[b], $MachinePrecision], 2.0], N[(N[(1.0 + a), $MachinePrecision] / N[(N[(1.0 + a), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[(0.16666666666666666 * b), $MachinePrecision] * N[(b * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                                    
                                    \begin{array}{l}
                                    
                                    \\
                                    \begin{array}{l}
                                    \mathbf{if}\;e^{b} \leq 2:\\
                                    \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\
                                    
                                    \mathbf{else}:\\
                                    \;\;\;\;\frac{1}{\left(0.16666666666666666 \cdot b\right) \cdot \left(b \cdot b\right)}\\
                                    
                                    
                                    \end{array}
                                    \end{array}
                                    
                                    Derivation
                                    1. Split input into 2 regimes
                                    2. if (exp.f64 b) < 2

                                      1. Initial program 99.4%

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

                                        \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                      4. Step-by-step derivation
                                        1. lower-+.f6474.8

                                          \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                      5. Applied rewrites74.8%

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

                                        \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                      7. Step-by-step derivation
                                        1. lower-+.f6475.3

                                          \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                      8. Applied rewrites75.3%

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

                                        \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
                                      10. Step-by-step derivation
                                        1. Applied rewrites52.2%

                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]

                                        if 2 < (exp.f64 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. +-commutativeN/A

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

                                            \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
                                          4. lower-exp.f6498.7

                                            \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
                                        5. Applied rewrites98.7%

                                          \[\leadsto \color{blue}{\frac{1}{e^{b} + 1}} \]
                                        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 rewrites75.2%

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

                                            \[\leadsto \frac{1}{{b}^{3} \cdot \left(\frac{1}{6} + \color{blue}{\frac{1}{2} \cdot \frac{1}{b}}\right)} \]
                                          3. Step-by-step derivation
                                            1. Applied rewrites75.2%

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

                                              \[\leadsto \frac{1}{\left(\frac{1}{6} \cdot b\right) \cdot \left(b \cdot b\right)} \]
                                            3. Step-by-step derivation
                                              1. Applied rewrites75.2%

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

                                            Alternative 11: 83.2% accurate, 2.6× speedup?

                                            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -5 \cdot 10^{+41}:\\ \;\;\;\;{b}^{3} \cdot 0.020833333333333332\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{1 + e^{b}}\\ \end{array} \end{array} \]
                                            (FPCore (a b)
                                             :precision binary64
                                             (if (<= a -5e+41)
                                               (* (pow b 3.0) 0.020833333333333332)
                                               (/ 1.0 (+ 1.0 (exp b)))))
                                            double code(double a, double b) {
                                            	double tmp;
                                            	if (a <= -5e+41) {
                                            		tmp = pow(b, 3.0) * 0.020833333333333332;
                                            	} else {
                                            		tmp = 1.0 / (1.0 + exp(b));
                                            	}
                                            	return tmp;
                                            }
                                            
                                            real(8) function code(a, b)
                                                real(8), intent (in) :: a
                                                real(8), intent (in) :: b
                                                real(8) :: tmp
                                                if (a <= (-5d+41)) then
                                                    tmp = (b ** 3.0d0) * 0.020833333333333332d0
                                                else
                                                    tmp = 1.0d0 / (1.0d0 + exp(b))
                                                end if
                                                code = tmp
                                            end function
                                            
                                            public static double code(double a, double b) {
                                            	double tmp;
                                            	if (a <= -5e+41) {
                                            		tmp = Math.pow(b, 3.0) * 0.020833333333333332;
                                            	} else {
                                            		tmp = 1.0 / (1.0 + Math.exp(b));
                                            	}
                                            	return tmp;
                                            }
                                            
                                            def code(a, b):
                                            	tmp = 0
                                            	if a <= -5e+41:
                                            		tmp = math.pow(b, 3.0) * 0.020833333333333332
                                            	else:
                                            		tmp = 1.0 / (1.0 + math.exp(b))
                                            	return tmp
                                            
                                            function code(a, b)
                                            	tmp = 0.0
                                            	if (a <= -5e+41)
                                            		tmp = Float64((b ^ 3.0) * 0.020833333333333332);
                                            	else
                                            		tmp = Float64(1.0 / Float64(1.0 + exp(b)));
                                            	end
                                            	return tmp
                                            end
                                            
                                            function tmp_2 = code(a, b)
                                            	tmp = 0.0;
                                            	if (a <= -5e+41)
                                            		tmp = (b ^ 3.0) * 0.020833333333333332;
                                            	else
                                            		tmp = 1.0 / (1.0 + exp(b));
                                            	end
                                            	tmp_2 = tmp;
                                            end
                                            
                                            code[a_, b_] := If[LessEqual[a, -5e+41], N[(N[Power[b, 3.0], $MachinePrecision] * 0.020833333333333332), $MachinePrecision], N[(1.0 / N[(1.0 + N[Exp[b], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                                            
                                            \begin{array}{l}
                                            
                                            \\
                                            \begin{array}{l}
                                            \mathbf{if}\;a \leq -5 \cdot 10^{+41}:\\
                                            \;\;\;\;{b}^{3} \cdot 0.020833333333333332\\
                                            
                                            \mathbf{else}:\\
                                            \;\;\;\;\frac{1}{1 + e^{b}}\\
                                            
                                            
                                            \end{array}
                                            \end{array}
                                            
                                            Derivation
                                            1. Split input into 2 regimes
                                            2. if a < -5.00000000000000022e41

                                              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. +-commutativeN/A

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

                                                  \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
                                                4. lower-exp.f6431.3

                                                  \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
                                              5. Applied rewrites31.3%

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

                                                \[\leadsto \frac{1}{2} + \color{blue}{b \cdot \left(\frac{1}{48} \cdot {b}^{2} - \frac{1}{4}\right)} \]
                                              7. Step-by-step derivation
                                                1. Applied rewrites2.7%

                                                  \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(b \cdot b, 0.020833333333333332, -0.25\right), \color{blue}{b}, 0.5\right) \]
                                                2. Taylor expanded in b around inf

                                                  \[\leadsto \frac{1}{48} \cdot {b}^{\color{blue}{3}} \]
                                                3. Step-by-step derivation
                                                  1. Applied rewrites50.5%

                                                    \[\leadsto {b}^{3} \cdot 0.020833333333333332 \]

                                                  if -5.00000000000000022e41 < a

                                                  1. Initial program 99.5%

                                                    \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                  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. +-commutativeN/A

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

                                                      \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
                                                    4. lower-exp.f6495.1

                                                      \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
                                                  5. Applied rewrites95.1%

                                                    \[\leadsto \color{blue}{\frac{1}{e^{b} + 1}} \]
                                                4. Recombined 2 regimes into one program.
                                                5. Final simplification85.5%

                                                  \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -5 \cdot 10^{+41}:\\ \;\;\;\;{b}^{3} \cdot 0.020833333333333332\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{1 + e^{b}}\\ \end{array} \]
                                                6. Add Preprocessing

                                                Alternative 12: 58.9% accurate, 2.8× speedup?

                                                \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -1.9 \cdot 10^{+41}:\\ \;\;\;\;{b}^{3} \cdot 0.020833333333333332\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, b, 0.5\right), b, 1\right), b, 1\right) + \left(1 + a\right)}\\ \end{array} \end{array} \]
                                                (FPCore (a b)
                                                 :precision binary64
                                                 (if (<= a -1.9e+41)
                                                   (* (pow b 3.0) 0.020833333333333332)
                                                   (/
                                                    (+ 1.0 a)
                                                    (+ (fma (fma (fma 0.16666666666666666 b 0.5) b 1.0) b 1.0) (+ 1.0 a)))))
                                                double code(double a, double b) {
                                                	double tmp;
                                                	if (a <= -1.9e+41) {
                                                		tmp = pow(b, 3.0) * 0.020833333333333332;
                                                	} else {
                                                		tmp = (1.0 + a) / (fma(fma(fma(0.16666666666666666, b, 0.5), b, 1.0), b, 1.0) + (1.0 + a));
                                                	}
                                                	return tmp;
                                                }
                                                
                                                function code(a, b)
                                                	tmp = 0.0
                                                	if (a <= -1.9e+41)
                                                		tmp = Float64((b ^ 3.0) * 0.020833333333333332);
                                                	else
                                                		tmp = Float64(Float64(1.0 + a) / Float64(fma(fma(fma(0.16666666666666666, b, 0.5), b, 1.0), b, 1.0) + Float64(1.0 + a)));
                                                	end
                                                	return tmp
                                                end
                                                
                                                code[a_, b_] := If[LessEqual[a, -1.9e+41], N[(N[Power[b, 3.0], $MachinePrecision] * 0.020833333333333332), $MachinePrecision], N[(N[(1.0 + a), $MachinePrecision] / N[(N[(N[(N[(0.16666666666666666 * b + 0.5), $MachinePrecision] * b + 1.0), $MachinePrecision] * b + 1.0), $MachinePrecision] + N[(1.0 + a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                                                
                                                \begin{array}{l}
                                                
                                                \\
                                                \begin{array}{l}
                                                \mathbf{if}\;a \leq -1.9 \cdot 10^{+41}:\\
                                                \;\;\;\;{b}^{3} \cdot 0.020833333333333332\\
                                                
                                                \mathbf{else}:\\
                                                \;\;\;\;\frac{1 + a}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, b, 0.5\right), b, 1\right), b, 1\right) + \left(1 + a\right)}\\
                                                
                                                
                                                \end{array}
                                                \end{array}
                                                
                                                Derivation
                                                1. Split input into 2 regimes
                                                2. if a < -1.9000000000000001e41

                                                  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. +-commutativeN/A

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

                                                      \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
                                                    4. lower-exp.f6431.3

                                                      \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
                                                  5. Applied rewrites31.3%

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

                                                    \[\leadsto \frac{1}{2} + \color{blue}{b \cdot \left(\frac{1}{48} \cdot {b}^{2} - \frac{1}{4}\right)} \]
                                                  7. Step-by-step derivation
                                                    1. Applied rewrites2.7%

                                                      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(b \cdot b, 0.020833333333333332, -0.25\right), \color{blue}{b}, 0.5\right) \]
                                                    2. Taylor expanded in b around inf

                                                      \[\leadsto \frac{1}{48} \cdot {b}^{\color{blue}{3}} \]
                                                    3. Step-by-step derivation
                                                      1. Applied rewrites50.5%

                                                        \[\leadsto {b}^{3} \cdot 0.020833333333333332 \]

                                                      if -1.9000000000000001e41 < a

                                                      1. Initial program 99.5%

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

                                                        \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                                      4. Step-by-step derivation
                                                        1. lower-+.f6495.6

                                                          \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                                      5. Applied rewrites95.6%

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

                                                        \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                                      7. Step-by-step derivation
                                                        1. lower-+.f6495.8

                                                          \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                                      8. Applied rewrites95.8%

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

                                                        \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{\left(1 + b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right)\right)}} \]
                                                      10. Step-by-step derivation
                                                        1. +-commutativeN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{\left(b \cdot \left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right)\right) + 1\right)}} \]
                                                        2. *-commutativeN/A

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

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{\mathsf{fma}\left(1 + b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right), b, 1\right)}} \]
                                                        4. +-commutativeN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\color{blue}{b \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot b\right) + 1}, b, 1\right)} \]
                                                        5. *-commutativeN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\color{blue}{\left(\frac{1}{2} + \frac{1}{6} \cdot b\right) \cdot b} + 1, b, 1\right)} \]
                                                        6. metadata-evalN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\left(\color{blue}{\frac{1}{2} \cdot 1} + \frac{1}{6} \cdot b\right) \cdot b + 1, b, 1\right)} \]
                                                        7. lft-mult-inverseN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\left(\frac{1}{2} \cdot \color{blue}{\left(\frac{1}{b} \cdot b\right)} + \frac{1}{6} \cdot b\right) \cdot b + 1, b, 1\right)} \]
                                                        8. associate-*l*N/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\left(\color{blue}{\left(\frac{1}{2} \cdot \frac{1}{b}\right) \cdot b} + \frac{1}{6} \cdot b\right) \cdot b + 1, b, 1\right)} \]
                                                        9. *-commutativeN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\left(\color{blue}{b \cdot \left(\frac{1}{2} \cdot \frac{1}{b}\right)} + \frac{1}{6} \cdot b\right) \cdot b + 1, b, 1\right)} \]
                                                        10. *-commutativeN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\left(b \cdot \left(\frac{1}{2} \cdot \frac{1}{b}\right) + \color{blue}{b \cdot \frac{1}{6}}\right) \cdot b + 1, b, 1\right)} \]
                                                        11. distribute-lft-inN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\color{blue}{\left(b \cdot \left(\frac{1}{2} \cdot \frac{1}{b} + \frac{1}{6}\right)\right)} \cdot b + 1, b, 1\right)} \]
                                                        12. +-commutativeN/A

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

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(b \cdot \left(\frac{1}{6} + \frac{1}{2} \cdot \frac{1}{b}\right), b, 1\right)}, b, 1\right)} \]
                                                        14. distribute-lft-inN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{b \cdot \frac{1}{6} + b \cdot \left(\frac{1}{2} \cdot \frac{1}{b}\right)}, b, 1\right), b, 1\right)} \]
                                                        15. *-commutativeN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{\frac{1}{6} \cdot b} + b \cdot \left(\frac{1}{2} \cdot \frac{1}{b}\right), b, 1\right), b, 1\right)} \]
                                                        16. *-commutativeN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot b + \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{b}\right) \cdot b}, b, 1\right), b, 1\right)} \]
                                                        17. associate-*l*N/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot b + \color{blue}{\frac{1}{2} \cdot \left(\frac{1}{b} \cdot b\right)}, b, 1\right), b, 1\right)} \]
                                                        18. lft-mult-inverseN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot b + \frac{1}{2} \cdot \color{blue}{1}, b, 1\right), b, 1\right)} \]
                                                        19. metadata-evalN/A

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot b + \color{blue}{\frac{1}{2}}, b, 1\right), b, 1\right)} \]
                                                        20. lower-fma.f6464.5

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(0.16666666666666666, b, 0.5\right)}, b, 1\right), b, 1\right)} \]
                                                      11. Applied rewrites64.5%

                                                        \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, b, 0.5\right), b, 1\right), b, 1\right)}} \]
                                                    4. Recombined 2 regimes into one program.
                                                    5. Final simplification61.5%

                                                      \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -1.9 \cdot 10^{+41}:\\ \;\;\;\;{b}^{3} \cdot 0.020833333333333332\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + a}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, b, 0.5\right), b, 1\right), b, 1\right) + \left(1 + a\right)}\\ \end{array} \]
                                                    6. Add Preprocessing

                                                    Alternative 13: 57.3% accurate, 9.3× speedup?

                                                    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;b \leq 1.62:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\left(b \cdot b\right) \cdot \mathsf{fma}\left(0.16666666666666666, b, 0.5\right)}\\ \end{array} \end{array} \]
                                                    (FPCore (a b)
                                                     :precision binary64
                                                     (if (<= b 1.62)
                                                       (/ (+ 1.0 a) (+ (+ 1.0 a) 1.0))
                                                       (/ 1.0 (* (* b b) (fma 0.16666666666666666 b 0.5)))))
                                                    double code(double a, double b) {
                                                    	double tmp;
                                                    	if (b <= 1.62) {
                                                    		tmp = (1.0 + a) / ((1.0 + a) + 1.0);
                                                    	} else {
                                                    		tmp = 1.0 / ((b * b) * fma(0.16666666666666666, b, 0.5));
                                                    	}
                                                    	return tmp;
                                                    }
                                                    
                                                    function code(a, b)
                                                    	tmp = 0.0
                                                    	if (b <= 1.62)
                                                    		tmp = Float64(Float64(1.0 + a) / Float64(Float64(1.0 + a) + 1.0));
                                                    	else
                                                    		tmp = Float64(1.0 / Float64(Float64(b * b) * fma(0.16666666666666666, b, 0.5)));
                                                    	end
                                                    	return tmp
                                                    end
                                                    
                                                    code[a_, b_] := If[LessEqual[b, 1.62], N[(N[(1.0 + a), $MachinePrecision] / N[(N[(1.0 + a), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(N[(b * b), $MachinePrecision] * N[(0.16666666666666666 * b + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                                                    
                                                    \begin{array}{l}
                                                    
                                                    \\
                                                    \begin{array}{l}
                                                    \mathbf{if}\;b \leq 1.62:\\
                                                    \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\
                                                    
                                                    \mathbf{else}:\\
                                                    \;\;\;\;\frac{1}{\left(b \cdot b\right) \cdot \mathsf{fma}\left(0.16666666666666666, b, 0.5\right)}\\
                                                    
                                                    
                                                    \end{array}
                                                    \end{array}
                                                    
                                                    Derivation
                                                    1. Split input into 2 regimes
                                                    2. if b < 1.6200000000000001

                                                      1. Initial program 99.4%

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

                                                        \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                                      4. Step-by-step derivation
                                                        1. lower-+.f6474.8

                                                          \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                                      5. Applied rewrites74.8%

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

                                                        \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                                      7. Step-by-step derivation
                                                        1. lower-+.f6475.3

                                                          \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                                      8. Applied rewrites75.3%

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

                                                        \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
                                                      10. Step-by-step derivation
                                                        1. Applied rewrites52.2%

                                                          \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]

                                                        if 1.6200000000000001 < 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. +-commutativeN/A

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

                                                            \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
                                                          4. lower-exp.f6498.7

                                                            \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
                                                        5. Applied rewrites98.7%

                                                          \[\leadsto \color{blue}{\frac{1}{e^{b} + 1}} \]
                                                        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 rewrites75.2%

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

                                                            \[\leadsto \frac{1}{{b}^{3} \cdot \left(\frac{1}{6} + \color{blue}{\frac{1}{2} \cdot \frac{1}{b}}\right)} \]
                                                          3. Step-by-step derivation
                                                            1. Applied rewrites75.2%

                                                              \[\leadsto \frac{1}{\mathsf{fma}\left(0.16666666666666666, b, 0.5\right) \cdot \left(b \cdot \color{blue}{b}\right)} \]
                                                          4. Recombined 2 regimes into one program.
                                                          5. Final simplification58.7%

                                                            \[\leadsto \begin{array}{l} \mathbf{if}\;b \leq 1.62:\\ \;\;\;\;\frac{1 + a}{\left(1 + a\right) + 1}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\left(b \cdot b\right) \cdot \mathsf{fma}\left(0.16666666666666666, b, 0.5\right)}\\ \end{array} \]
                                                          6. Add Preprocessing

                                                          Alternative 14: 53.2% accurate, 11.2× speedup?

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

                                                            1. Initial program 99.4%

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

                                                              \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                                            4. Step-by-step derivation
                                                              1. lower-+.f6474.8

                                                                \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                                            5. Applied rewrites74.8%

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

                                                              \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                                            7. Step-by-step derivation
                                                              1. lower-+.f6475.3

                                                                \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                                            8. Applied rewrites75.3%

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

                                                              \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
                                                            10. Step-by-step derivation
                                                              1. Applied rewrites52.2%

                                                                \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]

                                                              if 2 < 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. +-commutativeN/A

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

                                                                  \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
                                                                4. lower-exp.f6498.7

                                                                  \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
                                                              5. Applied rewrites98.7%

                                                                \[\leadsto \color{blue}{\frac{1}{e^{b} + 1}} \]
                                                              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 rewrites75.2%

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

                                                                  \[\leadsto \frac{1}{{b}^{3} \cdot \left(\frac{1}{6} + \color{blue}{\frac{1}{2} \cdot \frac{1}{b}}\right)} \]
                                                                3. Step-by-step derivation
                                                                  1. Applied rewrites75.2%

                                                                    \[\leadsto \frac{1}{\mathsf{fma}\left(0.16666666666666666, b, 0.5\right) \cdot \left(b \cdot \color{blue}{b}\right)} \]
                                                                  2. Taylor expanded in b around 0

                                                                    \[\leadsto \frac{1}{\frac{1}{2} \cdot \left(b \cdot b\right)} \]
                                                                  3. Step-by-step derivation
                                                                    1. Applied rewrites52.3%

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

                                                                  Alternative 15: 40.0% accurate, 15.0× speedup?

                                                                  \[\begin{array}{l} \\ \frac{1 + a}{\left(1 + a\right) + 1} \end{array} \]
                                                                  (FPCore (a b) :precision binary64 (/ (+ 1.0 a) (+ (+ 1.0 a) 1.0)))
                                                                  double code(double a, double b) {
                                                                  	return (1.0 + a) / ((1.0 + a) + 1.0);
                                                                  }
                                                                  
                                                                  real(8) function code(a, b)
                                                                      real(8), intent (in) :: a
                                                                      real(8), intent (in) :: b
                                                                      code = (1.0d0 + a) / ((1.0d0 + a) + 1.0d0)
                                                                  end function
                                                                  
                                                                  public static double code(double a, double b) {
                                                                  	return (1.0 + a) / ((1.0 + a) + 1.0);
                                                                  }
                                                                  
                                                                  def code(a, b):
                                                                  	return (1.0 + a) / ((1.0 + a) + 1.0)
                                                                  
                                                                  function code(a, b)
                                                                  	return Float64(Float64(1.0 + a) / Float64(Float64(1.0 + a) + 1.0))
                                                                  end
                                                                  
                                                                  function tmp = code(a, b)
                                                                  	tmp = (1.0 + a) / ((1.0 + a) + 1.0);
                                                                  end
                                                                  
                                                                  code[a_, b_] := N[(N[(1.0 + a), $MachinePrecision] / N[(N[(1.0 + a), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]
                                                                  
                                                                  \begin{array}{l}
                                                                  
                                                                  \\
                                                                  \frac{1 + a}{\left(1 + a\right) + 1}
                                                                  \end{array}
                                                                  
                                                                  Derivation
                                                                  1. Initial program 99.6%

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

                                                                    \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                                                  4. Step-by-step derivation
                                                                    1. lower-+.f6481.6

                                                                      \[\leadsto \frac{\color{blue}{1 + a}}{e^{a} + e^{b}} \]
                                                                  5. Applied rewrites81.6%

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

                                                                    \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                                                  7. Step-by-step derivation
                                                                    1. lower-+.f6481.9

                                                                      \[\leadsto \frac{1 + a}{\color{blue}{\left(1 + a\right)} + e^{b}} \]
                                                                  8. Applied rewrites81.9%

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

                                                                    \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
                                                                  10. Step-by-step derivation
                                                                    1. Applied rewrites38.2%

                                                                      \[\leadsto \frac{1 + a}{\left(1 + a\right) + \color{blue}{1}} \]
                                                                    2. Add Preprocessing

                                                                    Alternative 16: 39.6% accurate, 15.0× speedup?

                                                                    \[\begin{array}{l} \\ \mathsf{fma}\left(\mathsf{fma}\left(0.375, a, -0.375 \cdot a + 0.25\right), a, 0.5\right) \end{array} \]
                                                                    (FPCore (a b)
                                                                     :precision binary64
                                                                     (fma (fma 0.375 a (+ (* -0.375 a) 0.25)) a 0.5))
                                                                    double code(double a, double b) {
                                                                    	return fma(fma(0.375, a, ((-0.375 * a) + 0.25)), a, 0.5);
                                                                    }
                                                                    
                                                                    function code(a, b)
                                                                    	return fma(fma(0.375, a, Float64(Float64(-0.375 * a) + 0.25)), a, 0.5)
                                                                    end
                                                                    
                                                                    code[a_, b_] := N[(N[(0.375 * a + N[(N[(-0.375 * a), $MachinePrecision] + 0.25), $MachinePrecision]), $MachinePrecision] * a + 0.5), $MachinePrecision]
                                                                    
                                                                    \begin{array}{l}
                                                                    
                                                                    \\
                                                                    \mathsf{fma}\left(\mathsf{fma}\left(0.375, a, -0.375 \cdot a + 0.25\right), a, 0.5\right)
                                                                    \end{array}
                                                                    
                                                                    Derivation
                                                                    1. Initial program 99.6%

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

                                                                      \[\leadsto \color{blue}{a \cdot \left(\left(a \cdot \left(\left(\frac{1}{2} \cdot \frac{1}{1 + e^{b}} + \frac{1}{{\left(1 + e^{b}\right)}^{3}}\right) - \frac{3}{2} \cdot \frac{1}{{\left(1 + e^{b}\right)}^{2}}\right) + \frac{1}{1 + e^{b}}\right) - \frac{1}{{\left(1 + e^{b}\right)}^{2}}\right) + \frac{1}{1 + e^{b}}} \]
                                                                    4. Applied rewrites81.7%

                                                                      \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.5, a, 1\right), \frac{1}{e^{b} + 1}, \frac{a}{{\left(e^{b} + 1\right)}^{3}} + \mathsf{fma}\left(a, 1.5, 1\right) \cdot \frac{-1}{{\left(e^{b} + 1\right)}^{2}}\right), a, \frac{1}{e^{b} + 1}\right)} \]
                                                                    5. Taylor expanded in b around 0

                                                                      \[\leadsto \frac{1}{2} + \color{blue}{a \cdot \left(\frac{1}{2} + \left(\frac{-1}{4} \cdot \left(1 + \frac{3}{2} \cdot a\right) + \left(\frac{1}{8} \cdot a + \frac{1}{4} \cdot a\right)\right)\right)} \]
                                                                    6. Step-by-step derivation
                                                                      1. Applied rewrites37.9%

                                                                        \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(0.375, a, 0.25 + -0.375 \cdot a\right), \color{blue}{a}, 0.5\right) \]
                                                                      2. Final simplification37.9%

                                                                        \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(0.375, a, -0.375 \cdot a + 0.25\right), a, 0.5\right) \]
                                                                      3. Add Preprocessing

                                                                      Alternative 17: 39.6% accurate, 45.0× speedup?

                                                                      \[\begin{array}{l} \\ \mathsf{fma}\left(0.25, a, 0.5\right) \end{array} \]
                                                                      (FPCore (a b) :precision binary64 (fma 0.25 a 0.5))
                                                                      double code(double a, double b) {
                                                                      	return fma(0.25, a, 0.5);
                                                                      }
                                                                      
                                                                      function code(a, b)
                                                                      	return fma(0.25, a, 0.5)
                                                                      end
                                                                      
                                                                      code[a_, b_] := N[(0.25 * a + 0.5), $MachinePrecision]
                                                                      
                                                                      \begin{array}{l}
                                                                      
                                                                      \\
                                                                      \mathsf{fma}\left(0.25, a, 0.5\right)
                                                                      \end{array}
                                                                      
                                                                      Derivation
                                                                      1. Initial program 99.6%

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

                                                                        \[\leadsto \color{blue}{a \cdot \left(\left(a \cdot \left(\left(\frac{1}{2} \cdot \frac{1}{1 + e^{b}} + \frac{1}{{\left(1 + e^{b}\right)}^{3}}\right) - \frac{3}{2} \cdot \frac{1}{{\left(1 + e^{b}\right)}^{2}}\right) + \frac{1}{1 + e^{b}}\right) - \frac{1}{{\left(1 + e^{b}\right)}^{2}}\right) + \frac{1}{1 + e^{b}}} \]
                                                                      4. Applied rewrites81.7%

                                                                        \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.5, a, 1\right), \frac{1}{e^{b} + 1}, \frac{a}{{\left(e^{b} + 1\right)}^{3}} + \mathsf{fma}\left(a, 1.5, 1\right) \cdot \frac{-1}{{\left(e^{b} + 1\right)}^{2}}\right), a, \frac{1}{e^{b} + 1}\right)} \]
                                                                      5. Taylor expanded in b around 0

                                                                        \[\leadsto \frac{1}{2} + \color{blue}{a \cdot \left(\frac{1}{2} + \left(\frac{-1}{4} \cdot \left(1 + \frac{3}{2} \cdot a\right) + \left(\frac{1}{8} \cdot a + \frac{1}{4} \cdot a\right)\right)\right)} \]
                                                                      6. Step-by-step derivation
                                                                        1. Applied rewrites37.9%

                                                                          \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(0.375, a, 0.25 + -0.375 \cdot a\right), \color{blue}{a}, 0.5\right) \]
                                                                        2. Taylor expanded in a around 0

                                                                          \[\leadsto \mathsf{fma}\left(\frac{1}{4}, a, \frac{1}{2}\right) \]
                                                                        3. Step-by-step derivation
                                                                          1. Applied rewrites37.9%

                                                                            \[\leadsto \mathsf{fma}\left(0.25, a, 0.5\right) \]
                                                                          2. Add Preprocessing

                                                                          Alternative 18: 39.4% 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 99.6%

                                                                            \[\frac{e^{a}}{e^{a} + e^{b}} \]
                                                                          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. +-commutativeN/A

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

                                                                              \[\leadsto \frac{1}{\color{blue}{e^{b} + 1}} \]
                                                                            4. lower-exp.f6481.4

                                                                              \[\leadsto \frac{1}{\color{blue}{e^{b}} + 1} \]
                                                                          5. Applied rewrites81.4%

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

                                                                            \[\leadsto \frac{1}{2} \]
                                                                          7. Step-by-step derivation
                                                                            1. Applied rewrites37.6%

                                                                              \[\leadsto 0.5 \]
                                                                            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 2024268 
                                                                            (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))))