Logarithmic Transform

Percentage Accurate: 41.0% → 99.1%
Time: 6.1s
Alternatives: 8
Speedup: 19.8×

Specification

?
\[\begin{array}{l} \\ c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \end{array} \]
(FPCore (c x y)
 :precision binary64
 (* c (log (+ 1.0 (* (- (pow E x) 1.0) y)))))
double code(double c, double x, double y) {
	return c * log((1.0 + ((pow(((double) M_E), x) - 1.0) * y)));
}
public static double code(double c, double x, double y) {
	return c * Math.log((1.0 + ((Math.pow(Math.E, x) - 1.0) * y)));
}
def code(c, x, y):
	return c * math.log((1.0 + ((math.pow(math.e, x) - 1.0) * y)))
function code(c, x, y)
	return Float64(c * log(Float64(1.0 + Float64(Float64((exp(1) ^ x) - 1.0) * y))))
end
function tmp = code(c, x, y)
	tmp = c * log((1.0 + (((2.71828182845904523536 ^ x) - 1.0) * y)));
end
code[c_, x_, y_] := N[(c * N[Log[N[(1.0 + N[(N[(N[Power[E, x], $MachinePrecision] - 1.0), $MachinePrecision] * y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)
\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 8 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: 41.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \end{array} \]
(FPCore (c x y)
 :precision binary64
 (* c (log (+ 1.0 (* (- (pow E x) 1.0) y)))))
double code(double c, double x, double y) {
	return c * log((1.0 + ((pow(((double) M_E), x) - 1.0) * y)));
}
public static double code(double c, double x, double y) {
	return c * Math.log((1.0 + ((Math.pow(Math.E, x) - 1.0) * y)));
}
def code(c, x, y):
	return c * math.log((1.0 + ((math.pow(math.e, x) - 1.0) * y)))
function code(c, x, y)
	return Float64(c * log(Float64(1.0 + Float64(Float64((exp(1) ^ x) - 1.0) * y))))
end
function tmp = code(c, x, y)
	tmp = c * log((1.0 + (((2.71828182845904523536 ^ x) - 1.0) * y)));
end
code[c_, x_, y_] := N[(c * N[Log[N[(1.0 + N[(N[(N[Power[E, x], $MachinePrecision] - 1.0), $MachinePrecision] * y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)
\end{array}

Alternative 1: 99.1% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -4 \cdot 10^{-16}:\\ \;\;\;\;\mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \end{array} \]
(FPCore (c x y)
 :precision binary64
 (if (<= y -4e-16)
   (* (log1p (* (expm1 x) y)) c)
   (if (<= y 1.0)
     (* (expm1 x) (* y c))
     (*
      (log1p
       (*
        (*
         (fma
          (fma (fma 0.041666666666666664 x 0.16666666666666666) x 0.5)
          x
          1.0)
         x)
        y))
      c))))
double code(double c, double x, double y) {
	double tmp;
	if (y <= -4e-16) {
		tmp = log1p((expm1(x) * y)) * c;
	} else if (y <= 1.0) {
		tmp = expm1(x) * (y * c);
	} else {
		tmp = log1p(((fma(fma(fma(0.041666666666666664, x, 0.16666666666666666), x, 0.5), x, 1.0) * x) * y)) * c;
	}
	return tmp;
}
function code(c, x, y)
	tmp = 0.0
	if (y <= -4e-16)
		tmp = Float64(log1p(Float64(expm1(x) * y)) * c);
	elseif (y <= 1.0)
		tmp = Float64(expm1(x) * Float64(y * c));
	else
		tmp = Float64(log1p(Float64(Float64(fma(fma(fma(0.041666666666666664, x, 0.16666666666666666), x, 0.5), x, 1.0) * x) * y)) * c);
	end
	return tmp
end
code[c_, x_, y_] := If[LessEqual[y, -4e-16], N[(N[Log[1 + N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], If[LessEqual[y, 1.0], N[(N[(Exp[x] - 1), $MachinePrecision] * N[(y * c), $MachinePrecision]), $MachinePrecision], N[(N[Log[1 + N[(N[(N[(N[(N[(0.041666666666666664 * x + 0.16666666666666666), $MachinePrecision] * x + 0.5), $MachinePrecision] * x + 1.0), $MachinePrecision] * x), $MachinePrecision] * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -4 \cdot 10^{-16}:\\
\;\;\;\;\mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\

\mathbf{elif}\;y \leq 1:\\
\;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < -3.9999999999999999e-16

    1. Initial program 48.6%

      \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \color{blue}{c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
      2. lift-log.f64N/A

        \[\leadsto c \cdot \color{blue}{\log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
      3. lift-+.f64N/A

        \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
      4. lift-*.f64N/A

        \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right) \cdot y}\right) \]
      5. lift--.f64N/A

        \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right)} \cdot y\right) \]
      6. lift-E.f64N/A

        \[\leadsto c \cdot \log \left(1 + \left({\color{blue}{\mathsf{E}\left(\right)}}^{x} - 1\right) \cdot y\right) \]
      7. lift-pow.f64N/A

        \[\leadsto c \cdot \log \left(1 + \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \cdot y\right) \]
      8. *-commutativeN/A

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      9. lower-*.f64N/A

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
    4. Applied rewrites99.6%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
    5. Taylor expanded in x around 0

      \[\leadsto \mathsf{log1p}\left(\mathsf{expm1}\left(\color{blue}{x}\right) \cdot y\right) \cdot c \]
    6. Step-by-step derivation
      1. Applied rewrites99.6%

        \[\leadsto \mathsf{log1p}\left(\mathsf{expm1}\left(\color{blue}{x}\right) \cdot y\right) \cdot c \]

      if -3.9999999999999999e-16 < y < 1

      1. Initial program 32.4%

        \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
      2. Add Preprocessing
      3. Taylor expanded in y around 0

        \[\leadsto \color{blue}{c \cdot \left(y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)\right)} \]
      4. Step-by-step derivation
        1. associate-*r*N/A

          \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
        2. lower-*.f64N/A

          \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
        3. lower-*.f64N/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \]
        4. pow-to-expN/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(e^{\log \mathsf{E}\left(\right) \cdot x} - 1\right) \]
        5. log-EN/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(e^{1 \cdot x} - 1\right) \]
        6. *-commutativeN/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
        7. lower-expm1.f64N/A

          \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
        8. lower-*.f6498.0

          \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
      5. Applied rewrites98.0%

        \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]
      6. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\mathsf{expm1}\left(x \cdot 1\right)} \]
        2. lift-*.f64N/A

          \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(\color{blue}{x \cdot 1}\right) \]
        3. lift-*.f64N/A

          \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
        4. lift-expm1.f64N/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - \color{blue}{1}\right) \]
        5. *-commutativeN/A

          \[\leadsto \color{blue}{\left(c \cdot y\right)} \cdot \left(e^{x \cdot 1} - 1\right) \]
        6. pow-to-expN/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
        7. log-EN/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
        8. *-commutativeN/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
        9. *-rgt-identityN/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
        10. lower-expm1.f64N/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
        11. *-rgt-identityN/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
        12. lift-expm1.f64N/A

          \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
        13. *-commutativeN/A

          \[\leadsto \left(e^{x \cdot 1} - 1\right) \cdot \color{blue}{\left(c \cdot y\right)} \]
      7. Applied rewrites98.0%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)} \]

      if 1 < y

      1. Initial program 30.3%

        \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \color{blue}{c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
        2. lift-log.f64N/A

          \[\leadsto c \cdot \color{blue}{\log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
        3. lift-+.f64N/A

          \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
        4. lift-*.f64N/A

          \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right) \cdot y}\right) \]
        5. lift--.f64N/A

          \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right)} \cdot y\right) \]
        6. lift-E.f64N/A

          \[\leadsto c \cdot \log \left(1 + \left({\color{blue}{\mathsf{E}\left(\right)}}^{x} - 1\right) \cdot y\right) \]
        7. lift-pow.f64N/A

          \[\leadsto c \cdot \log \left(1 + \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \cdot y\right) \]
        8. *-commutativeN/A

          \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
        9. lower-*.f64N/A

          \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      4. Applied rewrites99.7%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
      5. Taylor expanded in x around 0

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left(x \cdot \left(1 + x \cdot \left(\frac{1}{2} + x \cdot \left(\frac{1}{6} + \frac{1}{24} \cdot x\right)\right)\right)\right)} \cdot y\right) \cdot c \]
      6. Applied rewrites99.7%

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right)} \cdot y\right) \cdot c \]
    7. Recombined 3 regimes into one program.
    8. Final simplification98.6%

      \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -4 \cdot 10^{-16}:\\ \;\;\;\;\mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \]
    9. Add Preprocessing

    Alternative 2: 89.6% accurate, 1.5× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.32 \cdot 10^{-14}:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \end{array} \]
    (FPCore (c x y)
     :precision binary64
     (if (<= y -1.32e-14)
       (* (log1p (* x y)) c)
       (if (<= y 1.0)
         (* (expm1 x) (* y c))
         (*
          (log1p
           (*
            (*
             (fma
              (fma (fma 0.041666666666666664 x 0.16666666666666666) x 0.5)
              x
              1.0)
             x)
            y))
          c))))
    double code(double c, double x, double y) {
    	double tmp;
    	if (y <= -1.32e-14) {
    		tmp = log1p((x * y)) * c;
    	} else if (y <= 1.0) {
    		tmp = expm1(x) * (y * c);
    	} else {
    		tmp = log1p(((fma(fma(fma(0.041666666666666664, x, 0.16666666666666666), x, 0.5), x, 1.0) * x) * y)) * c;
    	}
    	return tmp;
    }
    
    function code(c, x, y)
    	tmp = 0.0
    	if (y <= -1.32e-14)
    		tmp = Float64(log1p(Float64(x * y)) * c);
    	elseif (y <= 1.0)
    		tmp = Float64(expm1(x) * Float64(y * c));
    	else
    		tmp = Float64(log1p(Float64(Float64(fma(fma(fma(0.041666666666666664, x, 0.16666666666666666), x, 0.5), x, 1.0) * x) * y)) * c);
    	end
    	return tmp
    end
    
    code[c_, x_, y_] := If[LessEqual[y, -1.32e-14], N[(N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], If[LessEqual[y, 1.0], N[(N[(Exp[x] - 1), $MachinePrecision] * N[(y * c), $MachinePrecision]), $MachinePrecision], N[(N[Log[1 + N[(N[(N[(N[(N[(0.041666666666666664 * x + 0.16666666666666666), $MachinePrecision] * x + 0.5), $MachinePrecision] * x + 1.0), $MachinePrecision] * x), $MachinePrecision] * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;y \leq -1.32 \cdot 10^{-14}:\\
    \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\
    
    \mathbf{elif}\;y \leq 1:\\
    \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if y < -1.32e-14

      1. Initial program 48.6%

        \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \color{blue}{c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
        2. lift-log.f64N/A

          \[\leadsto c \cdot \color{blue}{\log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
        3. lift-+.f64N/A

          \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
        4. lift-*.f64N/A

          \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right) \cdot y}\right) \]
        5. lift--.f64N/A

          \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right)} \cdot y\right) \]
        6. lift-E.f64N/A

          \[\leadsto c \cdot \log \left(1 + \left({\color{blue}{\mathsf{E}\left(\right)}}^{x} - 1\right) \cdot y\right) \]
        7. lift-pow.f64N/A

          \[\leadsto c \cdot \log \left(1 + \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \cdot y\right) \]
        8. *-commutativeN/A

          \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
        9. lower-*.f64N/A

          \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      4. Applied rewrites99.6%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
      5. Taylor expanded in x around 0

        \[\leadsto \mathsf{log1p}\left(\color{blue}{x} \cdot y\right) \cdot c \]
      6. Step-by-step derivation
        1. Applied rewrites62.3%

          \[\leadsto \mathsf{log1p}\left(\color{blue}{x} \cdot y\right) \cdot c \]

        if -1.32e-14 < y < 1

        1. Initial program 32.4%

          \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
        2. Add Preprocessing
        3. Taylor expanded in y around 0

          \[\leadsto \color{blue}{c \cdot \left(y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)\right)} \]
        4. Step-by-step derivation
          1. associate-*r*N/A

            \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
          2. lower-*.f64N/A

            \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
          3. lower-*.f64N/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \]
          4. pow-to-expN/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(e^{\log \mathsf{E}\left(\right) \cdot x} - 1\right) \]
          5. log-EN/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(e^{1 \cdot x} - 1\right) \]
          6. *-commutativeN/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
          7. lower-expm1.f64N/A

            \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
          8. lower-*.f6498.0

            \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
        5. Applied rewrites98.0%

          \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]
        6. Step-by-step derivation
          1. lift-*.f64N/A

            \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\mathsf{expm1}\left(x \cdot 1\right)} \]
          2. lift-*.f64N/A

            \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(\color{blue}{x \cdot 1}\right) \]
          3. lift-*.f64N/A

            \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
          4. lift-expm1.f64N/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - \color{blue}{1}\right) \]
          5. *-commutativeN/A

            \[\leadsto \color{blue}{\left(c \cdot y\right)} \cdot \left(e^{x \cdot 1} - 1\right) \]
          6. pow-to-expN/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
          7. log-EN/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
          8. *-commutativeN/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
          9. *-rgt-identityN/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
          10. lower-expm1.f64N/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
          11. *-rgt-identityN/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
          12. lift-expm1.f64N/A

            \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
          13. *-commutativeN/A

            \[\leadsto \left(e^{x \cdot 1} - 1\right) \cdot \color{blue}{\left(c \cdot y\right)} \]
        7. Applied rewrites98.0%

          \[\leadsto \color{blue}{\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)} \]

        if 1 < y

        1. Initial program 30.3%

          \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. lift-*.f64N/A

            \[\leadsto \color{blue}{c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
          2. lift-log.f64N/A

            \[\leadsto c \cdot \color{blue}{\log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
          3. lift-+.f64N/A

            \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
          4. lift-*.f64N/A

            \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right) \cdot y}\right) \]
          5. lift--.f64N/A

            \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right)} \cdot y\right) \]
          6. lift-E.f64N/A

            \[\leadsto c \cdot \log \left(1 + \left({\color{blue}{\mathsf{E}\left(\right)}}^{x} - 1\right) \cdot y\right) \]
          7. lift-pow.f64N/A

            \[\leadsto c \cdot \log \left(1 + \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \cdot y\right) \]
          8. *-commutativeN/A

            \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
          9. lower-*.f64N/A

            \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
        4. Applied rewrites99.7%

          \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
        5. Taylor expanded in x around 0

          \[\leadsto \mathsf{log1p}\left(\color{blue}{\left(x \cdot \left(1 + x \cdot \left(\frac{1}{2} + x \cdot \left(\frac{1}{6} + \frac{1}{24} \cdot x\right)\right)\right)\right)} \cdot y\right) \cdot c \]
        6. Applied rewrites99.7%

          \[\leadsto \mathsf{log1p}\left(\color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right)} \cdot y\right) \cdot c \]
      7. Recombined 3 regimes into one program.
      8. Final simplification89.6%

        \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.32 \cdot 10^{-14}:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \]
      9. Add Preprocessing

      Alternative 3: 89.6% accurate, 1.6× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.32 \cdot 10^{-14}:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \end{array} \]
      (FPCore (c x y)
       :precision binary64
       (if (<= y -1.32e-14)
         (* (log1p (* x y)) c)
         (if (<= y 1.0)
           (* (expm1 x) (* y c))
           (* (log1p (* (* (fma (fma 0.16666666666666666 x 0.5) x 1.0) x) y)) c))))
      double code(double c, double x, double y) {
      	double tmp;
      	if (y <= -1.32e-14) {
      		tmp = log1p((x * y)) * c;
      	} else if (y <= 1.0) {
      		tmp = expm1(x) * (y * c);
      	} else {
      		tmp = log1p(((fma(fma(0.16666666666666666, x, 0.5), x, 1.0) * x) * y)) * c;
      	}
      	return tmp;
      }
      
      function code(c, x, y)
      	tmp = 0.0
      	if (y <= -1.32e-14)
      		tmp = Float64(log1p(Float64(x * y)) * c);
      	elseif (y <= 1.0)
      		tmp = Float64(expm1(x) * Float64(y * c));
      	else
      		tmp = Float64(log1p(Float64(Float64(fma(fma(0.16666666666666666, x, 0.5), x, 1.0) * x) * y)) * c);
      	end
      	return tmp
      end
      
      code[c_, x_, y_] := If[LessEqual[y, -1.32e-14], N[(N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], If[LessEqual[y, 1.0], N[(N[(Exp[x] - 1), $MachinePrecision] * N[(y * c), $MachinePrecision]), $MachinePrecision], N[(N[Log[1 + N[(N[(N[(N[(0.16666666666666666 * x + 0.5), $MachinePrecision] * x + 1.0), $MachinePrecision] * x), $MachinePrecision] * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;y \leq -1.32 \cdot 10^{-14}:\\
      \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\
      
      \mathbf{elif}\;y \leq 1:\\
      \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if y < -1.32e-14

        1. Initial program 48.6%

          \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. lift-*.f64N/A

            \[\leadsto \color{blue}{c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
          2. lift-log.f64N/A

            \[\leadsto c \cdot \color{blue}{\log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
          3. lift-+.f64N/A

            \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
          4. lift-*.f64N/A

            \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right) \cdot y}\right) \]
          5. lift--.f64N/A

            \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right)} \cdot y\right) \]
          6. lift-E.f64N/A

            \[\leadsto c \cdot \log \left(1 + \left({\color{blue}{\mathsf{E}\left(\right)}}^{x} - 1\right) \cdot y\right) \]
          7. lift-pow.f64N/A

            \[\leadsto c \cdot \log \left(1 + \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \cdot y\right) \]
          8. *-commutativeN/A

            \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
          9. lower-*.f64N/A

            \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
        4. Applied rewrites99.6%

          \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
        5. Taylor expanded in x around 0

          \[\leadsto \mathsf{log1p}\left(\color{blue}{x} \cdot y\right) \cdot c \]
        6. Step-by-step derivation
          1. Applied rewrites62.3%

            \[\leadsto \mathsf{log1p}\left(\color{blue}{x} \cdot y\right) \cdot c \]

          if -1.32e-14 < y < 1

          1. Initial program 32.4%

            \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
          2. Add Preprocessing
          3. Taylor expanded in y around 0

            \[\leadsto \color{blue}{c \cdot \left(y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)\right)} \]
          4. Step-by-step derivation
            1. associate-*r*N/A

              \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
            2. lower-*.f64N/A

              \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
            3. lower-*.f64N/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \]
            4. pow-to-expN/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(e^{\log \mathsf{E}\left(\right) \cdot x} - 1\right) \]
            5. log-EN/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(e^{1 \cdot x} - 1\right) \]
            6. *-commutativeN/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
            7. lower-expm1.f64N/A

              \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
            8. lower-*.f6498.0

              \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
          5. Applied rewrites98.0%

            \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]
          6. Step-by-step derivation
            1. lift-*.f64N/A

              \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\mathsf{expm1}\left(x \cdot 1\right)} \]
            2. lift-*.f64N/A

              \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(\color{blue}{x \cdot 1}\right) \]
            3. lift-*.f64N/A

              \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
            4. lift-expm1.f64N/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - \color{blue}{1}\right) \]
            5. *-commutativeN/A

              \[\leadsto \color{blue}{\left(c \cdot y\right)} \cdot \left(e^{x \cdot 1} - 1\right) \]
            6. pow-to-expN/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
            7. log-EN/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
            8. *-commutativeN/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
            9. *-rgt-identityN/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
            10. lower-expm1.f64N/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
            11. *-rgt-identityN/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
            12. lift-expm1.f64N/A

              \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
            13. *-commutativeN/A

              \[\leadsto \left(e^{x \cdot 1} - 1\right) \cdot \color{blue}{\left(c \cdot y\right)} \]
          7. Applied rewrites98.0%

            \[\leadsto \color{blue}{\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)} \]

          if 1 < y

          1. Initial program 30.3%

            \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto c \cdot \log \left(1 + \color{blue}{\left(x \cdot \left(\log \mathsf{E}\left(\right) + x \cdot \left(\frac{1}{6} \cdot \left(x \cdot {\log \mathsf{E}\left(\right)}^{3}\right) + \frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2}\right)\right)\right)} \cdot y\right) \]
          4. Step-by-step derivation
            1. *-commutativeN/A

              \[\leadsto c \cdot \log \left(1 + \left(\left(\log \mathsf{E}\left(\right) + x \cdot \left(\frac{1}{6} \cdot \left(x \cdot {\log \mathsf{E}\left(\right)}^{3}\right) + \frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2}\right)\right) \cdot \color{blue}{x}\right) \cdot y\right) \]
            2. lower-*.f64N/A

              \[\leadsto c \cdot \log \left(1 + \left(\left(\log \mathsf{E}\left(\right) + x \cdot \left(\frac{1}{6} \cdot \left(x \cdot {\log \mathsf{E}\left(\right)}^{3}\right) + \frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2}\right)\right) \cdot \color{blue}{x}\right) \cdot y\right) \]
          5. Applied rewrites55.7%

            \[\leadsto c \cdot \log \left(1 + \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666 \cdot x, 1, 0.5\right), x, 1\right) \cdot x\right)} \cdot y\right) \]
          6. Step-by-step derivation
            1. lift-*.f64N/A

              \[\leadsto \color{blue}{c \cdot \log \left(1 + \left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot x, 1, \frac{1}{2}\right), x, 1\right) \cdot x\right) \cdot y\right)} \]
            2. *-commutativeN/A

              \[\leadsto \color{blue}{\log \left(1 + \left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{6} \cdot x, 1, \frac{1}{2}\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c} \]
            3. lower-*.f6455.7

              \[\leadsto \color{blue}{\log \left(1 + \left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666 \cdot x, 1, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c} \]
          7. Applied rewrites99.4%

            \[\leadsto \color{blue}{\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c} \]
        7. Recombined 3 regimes into one program.
        8. Final simplification89.6%

          \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.32 \cdot 10^{-14}:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \]
        9. Add Preprocessing

        Alternative 4: 89.6% accurate, 1.6× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.32 \cdot 10^{-14}:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \end{array} \]
        (FPCore (c x y)
         :precision binary64
         (if (<= y -1.32e-14)
           (* (log1p (* x y)) c)
           (if (<= y 1.0)
             (* (expm1 x) (* y c))
             (* (log1p (* (* (fma 0.5 x 1.0) x) y)) c))))
        double code(double c, double x, double y) {
        	double tmp;
        	if (y <= -1.32e-14) {
        		tmp = log1p((x * y)) * c;
        	} else if (y <= 1.0) {
        		tmp = expm1(x) * (y * c);
        	} else {
        		tmp = log1p(((fma(0.5, x, 1.0) * x) * y)) * c;
        	}
        	return tmp;
        }
        
        function code(c, x, y)
        	tmp = 0.0
        	if (y <= -1.32e-14)
        		tmp = Float64(log1p(Float64(x * y)) * c);
        	elseif (y <= 1.0)
        		tmp = Float64(expm1(x) * Float64(y * c));
        	else
        		tmp = Float64(log1p(Float64(Float64(fma(0.5, x, 1.0) * x) * y)) * c);
        	end
        	return tmp
        end
        
        code[c_, x_, y_] := If[LessEqual[y, -1.32e-14], N[(N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], If[LessEqual[y, 1.0], N[(N[(Exp[x] - 1), $MachinePrecision] * N[(y * c), $MachinePrecision]), $MachinePrecision], N[(N[Log[1 + N[(N[(N[(0.5 * x + 1.0), $MachinePrecision] * x), $MachinePrecision] * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision]]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;y \leq -1.32 \cdot 10^{-14}:\\
        \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\
        
        \mathbf{elif}\;y \leq 1:\\
        \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 3 regimes
        2. if y < -1.32e-14

          1. Initial program 48.6%

            \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-*.f64N/A

              \[\leadsto \color{blue}{c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
            2. lift-log.f64N/A

              \[\leadsto c \cdot \color{blue}{\log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
            3. lift-+.f64N/A

              \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
            4. lift-*.f64N/A

              \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right) \cdot y}\right) \]
            5. lift--.f64N/A

              \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right)} \cdot y\right) \]
            6. lift-E.f64N/A

              \[\leadsto c \cdot \log \left(1 + \left({\color{blue}{\mathsf{E}\left(\right)}}^{x} - 1\right) \cdot y\right) \]
            7. lift-pow.f64N/A

              \[\leadsto c \cdot \log \left(1 + \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \cdot y\right) \]
            8. *-commutativeN/A

              \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
            9. lower-*.f64N/A

              \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
          4. Applied rewrites99.6%

            \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
          5. Taylor expanded in x around 0

            \[\leadsto \mathsf{log1p}\left(\color{blue}{x} \cdot y\right) \cdot c \]
          6. Step-by-step derivation
            1. Applied rewrites62.3%

              \[\leadsto \mathsf{log1p}\left(\color{blue}{x} \cdot y\right) \cdot c \]

            if -1.32e-14 < y < 1

            1. Initial program 32.4%

              \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
            2. Add Preprocessing
            3. Taylor expanded in y around 0

              \[\leadsto \color{blue}{c \cdot \left(y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)\right)} \]
            4. Step-by-step derivation
              1. associate-*r*N/A

                \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
              2. lower-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
              3. lower-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \]
              4. pow-to-expN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{\log \mathsf{E}\left(\right) \cdot x} - 1\right) \]
              5. log-EN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{1 \cdot x} - 1\right) \]
              6. *-commutativeN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              7. lower-expm1.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
              8. lower-*.f6498.0

                \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
            5. Applied rewrites98.0%

              \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]
            6. Step-by-step derivation
              1. lift-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\mathsf{expm1}\left(x \cdot 1\right)} \]
              2. lift-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(\color{blue}{x \cdot 1}\right) \]
              3. lift-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
              4. lift-expm1.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - \color{blue}{1}\right) \]
              5. *-commutativeN/A

                \[\leadsto \color{blue}{\left(c \cdot y\right)} \cdot \left(e^{x \cdot 1} - 1\right) \]
              6. pow-to-expN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              7. log-EN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              8. *-commutativeN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              9. *-rgt-identityN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              10. lower-expm1.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              11. *-rgt-identityN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              12. lift-expm1.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              13. *-commutativeN/A

                \[\leadsto \left(e^{x \cdot 1} - 1\right) \cdot \color{blue}{\left(c \cdot y\right)} \]
            7. Applied rewrites98.0%

              \[\leadsto \color{blue}{\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)} \]

            if 1 < y

            1. Initial program 30.3%

              \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
            2. Add Preprocessing
            3. Step-by-step derivation
              1. lift-*.f64N/A

                \[\leadsto \color{blue}{c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
              2. lift-log.f64N/A

                \[\leadsto c \cdot \color{blue}{\log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
              3. lift-+.f64N/A

                \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
              4. lift-*.f64N/A

                \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right) \cdot y}\right) \]
              5. lift--.f64N/A

                \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right)} \cdot y\right) \]
              6. lift-E.f64N/A

                \[\leadsto c \cdot \log \left(1 + \left({\color{blue}{\mathsf{E}\left(\right)}}^{x} - 1\right) \cdot y\right) \]
              7. lift-pow.f64N/A

                \[\leadsto c \cdot \log \left(1 + \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \cdot y\right) \]
              8. *-commutativeN/A

                \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
              9. lower-*.f64N/A

                \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
            4. Applied rewrites99.7%

              \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
            5. Taylor expanded in x around 0

              \[\leadsto \mathsf{log1p}\left(\color{blue}{\left(x \cdot \left(1 + \frac{1}{2} \cdot x\right)\right)} \cdot y\right) \cdot c \]
            6. Step-by-step derivation
              1. *-commutativeN/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(1 + \frac{1}{2} \cdot x\right) \cdot \color{blue}{x}\right) \cdot y\right) \cdot c \]
              2. lower-*.f64N/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(1 + \frac{1}{2} \cdot x\right) \cdot \color{blue}{x}\right) \cdot y\right) \cdot c \]
              3. +-commutativeN/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(\frac{1}{2} \cdot x + 1\right) \cdot x\right) \cdot y\right) \cdot c \]
              4. lower-fma.f6498.9

                \[\leadsto \mathsf{log1p}\left(\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right) \cdot y\right) \cdot c \]
            7. Applied rewrites98.9%

              \[\leadsto \mathsf{log1p}\left(\color{blue}{\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right)} \cdot y\right) \cdot c \]
          7. Recombined 3 regimes into one program.
          8. Final simplification89.5%

            \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.32 \cdot 10^{-14}:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \]
          9. Add Preprocessing

          Alternative 5: 89.6% accurate, 1.8× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.32 \cdot 10^{-14} \lor \neg \left(y \leq 1\right):\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\ \end{array} \end{array} \]
          (FPCore (c x y)
           :precision binary64
           (if (or (<= y -1.32e-14) (not (<= y 1.0)))
             (* (log1p (* x y)) c)
             (* (expm1 x) (* y c))))
          double code(double c, double x, double y) {
          	double tmp;
          	if ((y <= -1.32e-14) || !(y <= 1.0)) {
          		tmp = log1p((x * y)) * c;
          	} else {
          		tmp = expm1(x) * (y * c);
          	}
          	return tmp;
          }
          
          public static double code(double c, double x, double y) {
          	double tmp;
          	if ((y <= -1.32e-14) || !(y <= 1.0)) {
          		tmp = Math.log1p((x * y)) * c;
          	} else {
          		tmp = Math.expm1(x) * (y * c);
          	}
          	return tmp;
          }
          
          def code(c, x, y):
          	tmp = 0
          	if (y <= -1.32e-14) or not (y <= 1.0):
          		tmp = math.log1p((x * y)) * c
          	else:
          		tmp = math.expm1(x) * (y * c)
          	return tmp
          
          function code(c, x, y)
          	tmp = 0.0
          	if ((y <= -1.32e-14) || !(y <= 1.0))
          		tmp = Float64(log1p(Float64(x * y)) * c);
          	else
          		tmp = Float64(expm1(x) * Float64(y * c));
          	end
          	return tmp
          end
          
          code[c_, x_, y_] := If[Or[LessEqual[y, -1.32e-14], N[Not[LessEqual[y, 1.0]], $MachinePrecision]], N[(N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], N[(N[(Exp[x] - 1), $MachinePrecision] * N[(y * c), $MachinePrecision]), $MachinePrecision]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;y \leq -1.32 \cdot 10^{-14} \lor \neg \left(y \leq 1\right):\\
          \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\
          
          \mathbf{else}:\\
          \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if y < -1.32e-14 or 1 < y

            1. Initial program 41.3%

              \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
            2. Add Preprocessing
            3. Step-by-step derivation
              1. lift-*.f64N/A

                \[\leadsto \color{blue}{c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
              2. lift-log.f64N/A

                \[\leadsto c \cdot \color{blue}{\log \left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
              3. lift-+.f64N/A

                \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
              4. lift-*.f64N/A

                \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right) \cdot y}\right) \]
              5. lift--.f64N/A

                \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({e}^{x} - 1\right)} \cdot y\right) \]
              6. lift-E.f64N/A

                \[\leadsto c \cdot \log \left(1 + \left({\color{blue}{\mathsf{E}\left(\right)}}^{x} - 1\right) \cdot y\right) \]
              7. lift-pow.f64N/A

                \[\leadsto c \cdot \log \left(1 + \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \cdot y\right) \]
              8. *-commutativeN/A

                \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
              9. lower-*.f64N/A

                \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
            4. Applied rewrites99.6%

              \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
            5. Taylor expanded in x around 0

              \[\leadsto \mathsf{log1p}\left(\color{blue}{x} \cdot y\right) \cdot c \]
            6. Step-by-step derivation
              1. Applied rewrites76.6%

                \[\leadsto \mathsf{log1p}\left(\color{blue}{x} \cdot y\right) \cdot c \]

              if -1.32e-14 < y < 1

              1. Initial program 32.4%

                \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
              2. Add Preprocessing
              3. Taylor expanded in y around 0

                \[\leadsto \color{blue}{c \cdot \left(y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)\right)} \]
              4. Step-by-step derivation
                1. associate-*r*N/A

                  \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
                2. lower-*.f64N/A

                  \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
                3. lower-*.f64N/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \]
                4. pow-to-expN/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(e^{\log \mathsf{E}\left(\right) \cdot x} - 1\right) \]
                5. log-EN/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(e^{1 \cdot x} - 1\right) \]
                6. *-commutativeN/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
                7. lower-expm1.f64N/A

                  \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
                8. lower-*.f6498.0

                  \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
              5. Applied rewrites98.0%

                \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]
              6. Step-by-step derivation
                1. lift-*.f64N/A

                  \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\mathsf{expm1}\left(x \cdot 1\right)} \]
                2. lift-*.f64N/A

                  \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(\color{blue}{x \cdot 1}\right) \]
                3. lift-*.f64N/A

                  \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
                4. lift-expm1.f64N/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - \color{blue}{1}\right) \]
                5. *-commutativeN/A

                  \[\leadsto \color{blue}{\left(c \cdot y\right)} \cdot \left(e^{x \cdot 1} - 1\right) \]
                6. pow-to-expN/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
                7. log-EN/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
                8. *-commutativeN/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
                9. *-rgt-identityN/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
                10. lower-expm1.f64N/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
                11. *-rgt-identityN/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
                12. lift-expm1.f64N/A

                  \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
                13. *-commutativeN/A

                  \[\leadsto \left(e^{x \cdot 1} - 1\right) \cdot \color{blue}{\left(c \cdot y\right)} \]
              7. Applied rewrites98.0%

                \[\leadsto \color{blue}{\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)} \]
            7. Recombined 2 regimes into one program.
            8. Final simplification89.4%

              \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.32 \cdot 10^{-14} \lor \neg \left(y \leq 1\right):\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)\\ \end{array} \]
            9. Add Preprocessing

            Alternative 6: 76.5% accurate, 2.0× speedup?

            \[\begin{array}{l} \\ \mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right) \end{array} \]
            (FPCore (c x y) :precision binary64 (* (expm1 x) (* y c)))
            double code(double c, double x, double y) {
            	return expm1(x) * (y * c);
            }
            
            public static double code(double c, double x, double y) {
            	return Math.expm1(x) * (y * c);
            }
            
            def code(c, x, y):
            	return math.expm1(x) * (y * c)
            
            function code(c, x, y)
            	return Float64(expm1(x) * Float64(y * c))
            end
            
            code[c_, x_, y_] := N[(N[(Exp[x] - 1), $MachinePrecision] * N[(y * c), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)
            \end{array}
            
            Derivation
            1. Initial program 36.0%

              \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
            2. Add Preprocessing
            3. Taylor expanded in y around 0

              \[\leadsto \color{blue}{c \cdot \left(y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)\right)} \]
            4. Step-by-step derivation
              1. associate-*r*N/A

                \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
              2. lower-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
              3. lower-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \]
              4. pow-to-expN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{\log \mathsf{E}\left(\right) \cdot x} - 1\right) \]
              5. log-EN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{1 \cdot x} - 1\right) \]
              6. *-commutativeN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              7. lower-expm1.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
              8. lower-*.f6477.7

                \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
            5. Applied rewrites77.7%

              \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]
            6. Step-by-step derivation
              1. lift-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\mathsf{expm1}\left(x \cdot 1\right)} \]
              2. lift-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(\color{blue}{x \cdot 1}\right) \]
              3. lift-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
              4. lift-expm1.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - \color{blue}{1}\right) \]
              5. *-commutativeN/A

                \[\leadsto \color{blue}{\left(c \cdot y\right)} \cdot \left(e^{x \cdot 1} - 1\right) \]
              6. pow-to-expN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              7. log-EN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              8. *-commutativeN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              9. *-rgt-identityN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              10. lower-expm1.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              11. *-rgt-identityN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              12. lift-expm1.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              13. *-commutativeN/A

                \[\leadsto \left(e^{x \cdot 1} - 1\right) \cdot \color{blue}{\left(c \cdot y\right)} \]
            7. Applied rewrites77.7%

              \[\leadsto \color{blue}{\mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right)} \]
            8. Final simplification77.7%

              \[\leadsto \mathsf{expm1}\left(x\right) \cdot \left(y \cdot c\right) \]
            9. Add Preprocessing

            Alternative 7: 61.4% accurate, 19.8× speedup?

            \[\begin{array}{l} \\ \left(c \cdot y\right) \cdot x \end{array} \]
            (FPCore (c x y) :precision binary64 (* (* c y) x))
            double code(double c, double x, double y) {
            	return (c * y) * x;
            }
            
            module fmin_fmax_functions
                implicit none
                private
                public fmax
                public fmin
            
                interface fmax
                    module procedure fmax88
                    module procedure fmax44
                    module procedure fmax84
                    module procedure fmax48
                end interface
                interface fmin
                    module procedure fmin88
                    module procedure fmin44
                    module procedure fmin84
                    module procedure fmin48
                end interface
            contains
                real(8) function fmax88(x, y) result (res)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                end function
                real(4) function fmax44(x, y) result (res)
                    real(4), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                end function
                real(8) function fmax84(x, y) result(res)
                    real(8), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                end function
                real(8) function fmax48(x, y) result(res)
                    real(4), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                end function
                real(8) function fmin88(x, y) result (res)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                end function
                real(4) function fmin44(x, y) result (res)
                    real(4), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                end function
                real(8) function fmin84(x, y) result(res)
                    real(8), intent (in) :: x
                    real(4), intent (in) :: y
                    res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                end function
                real(8) function fmin48(x, y) result(res)
                    real(4), intent (in) :: x
                    real(8), intent (in) :: y
                    res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                end function
            end module
            
            real(8) function code(c, x, y)
            use fmin_fmax_functions
                real(8), intent (in) :: c
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                code = (c * y) * x
            end function
            
            public static double code(double c, double x, double y) {
            	return (c * y) * x;
            }
            
            def code(c, x, y):
            	return (c * y) * x
            
            function code(c, x, y)
            	return Float64(Float64(c * y) * x)
            end
            
            function tmp = code(c, x, y)
            	tmp = (c * y) * x;
            end
            
            code[c_, x_, y_] := N[(N[(c * y), $MachinePrecision] * x), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \left(c \cdot y\right) \cdot x
            \end{array}
            
            Derivation
            1. Initial program 36.0%

              \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
            2. Add Preprocessing
            3. Taylor expanded in y around 0

              \[\leadsto \color{blue}{c \cdot \left(y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)\right)} \]
            4. Step-by-step derivation
              1. associate-*r*N/A

                \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
              2. lower-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \]
              3. lower-*.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right) \]
              4. pow-to-expN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{\log \mathsf{E}\left(\right) \cdot x} - 1\right) \]
              5. log-EN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{1 \cdot x} - 1\right) \]
              6. *-commutativeN/A

                \[\leadsto \left(c \cdot y\right) \cdot \left(e^{x \cdot 1} - 1\right) \]
              7. lower-expm1.f64N/A

                \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
              8. lower-*.f6477.7

                \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
            5. Applied rewrites77.7%

              \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]
            6. Taylor expanded in x around 0

              \[\leadsto \left(c \cdot y\right) \cdot x \]
            7. Step-by-step derivation
              1. Applied rewrites61.3%

                \[\leadsto \left(c \cdot y\right) \cdot x \]
              2. Add Preprocessing

              Alternative 8: 58.2% accurate, 19.8× speedup?

              \[\begin{array}{l} \\ \left(c \cdot x\right) \cdot y \end{array} \]
              (FPCore (c x y) :precision binary64 (* (* c x) y))
              double code(double c, double x, double y) {
              	return (c * x) * y;
              }
              
              module fmin_fmax_functions
                  implicit none
                  private
                  public fmax
                  public fmin
              
                  interface fmax
                      module procedure fmax88
                      module procedure fmax44
                      module procedure fmax84
                      module procedure fmax48
                  end interface
                  interface fmin
                      module procedure fmin88
                      module procedure fmin44
                      module procedure fmin84
                      module procedure fmin48
                  end interface
              contains
                  real(8) function fmax88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmax44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmax84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmax48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                  end function
                  real(8) function fmin88(x, y) result (res)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(4) function fmin44(x, y) result (res)
                      real(4), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                  end function
                  real(8) function fmin84(x, y) result(res)
                      real(8), intent (in) :: x
                      real(4), intent (in) :: y
                      res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                  end function
                  real(8) function fmin48(x, y) result(res)
                      real(4), intent (in) :: x
                      real(8), intent (in) :: y
                      res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                  end function
              end module
              
              real(8) function code(c, x, y)
              use fmin_fmax_functions
                  real(8), intent (in) :: c
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  code = (c * x) * y
              end function
              
              public static double code(double c, double x, double y) {
              	return (c * x) * y;
              }
              
              def code(c, x, y):
              	return (c * x) * y
              
              function code(c, x, y)
              	return Float64(Float64(c * x) * y)
              end
              
              function tmp = code(c, x, y)
              	tmp = (c * x) * y;
              end
              
              code[c_, x_, y_] := N[(N[(c * x), $MachinePrecision] * y), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \left(c \cdot x\right) \cdot y
              \end{array}
              
              Derivation
              1. Initial program 36.0%

                \[c \cdot \log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \]
              2. Add Preprocessing
              3. Taylor expanded in x around 0

                \[\leadsto \color{blue}{c \cdot \left(x \cdot \left(y \cdot \log \mathsf{E}\left(\right)\right)\right)} \]
              4. Step-by-step derivation
                1. associate-*r*N/A

                  \[\leadsto \left(c \cdot x\right) \cdot \color{blue}{\left(y \cdot \log \mathsf{E}\left(\right)\right)} \]
                2. log-EN/A

                  \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot 1\right) \]
                3. lower-*.f64N/A

                  \[\leadsto \left(c \cdot x\right) \cdot \color{blue}{\left(y \cdot 1\right)} \]
                4. lower-*.f64N/A

                  \[\leadsto \left(c \cdot x\right) \cdot \left(\color{blue}{y} \cdot 1\right) \]
                5. lower-*.f6457.8

                  \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \color{blue}{1}\right) \]
              5. Applied rewrites57.8%

                \[\leadsto \color{blue}{\left(c \cdot x\right) \cdot \left(y \cdot 1\right)} \]
              6. Step-by-step derivation
                1. lift-*.f64N/A

                  \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \color{blue}{1}\right) \]
                2. *-rgt-identity57.8

                  \[\leadsto \left(c \cdot x\right) \cdot y \]
              7. Applied rewrites57.8%

                \[\leadsto \left(c \cdot x\right) \cdot \color{blue}{y} \]
              8. Add Preprocessing

              Developer Target 1: 93.7% accurate, 1.0× speedup?

              \[\begin{array}{l} \\ c \cdot \mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right) \end{array} \]
              (FPCore (c x y) :precision binary64 (* c (log1p (* (expm1 x) y))))
              double code(double c, double x, double y) {
              	return c * log1p((expm1(x) * y));
              }
              
              public static double code(double c, double x, double y) {
              	return c * Math.log1p((Math.expm1(x) * y));
              }
              
              def code(c, x, y):
              	return c * math.log1p((math.expm1(x) * y))
              
              function code(c, x, y)
              	return Float64(c * log1p(Float64(expm1(x) * y)))
              end
              
              code[c_, x_, y_] := N[(c * N[Log[1 + N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              c \cdot \mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right)
              \end{array}
              

              Reproduce

              ?
              herbie shell --seed 2025085 
              (FPCore (c x y)
                :name "Logarithmic Transform"
                :precision binary64
              
                :alt
                (* c (log1p (* (expm1 x) y)))
              
                (* c (log (+ 1.0 (* (- (pow E x) 1.0) y)))))