Logarithmic Transform

Percentage Accurate: 42.0% → 99.1%
Time: 29.0s
Alternatives: 9
Speedup: 19.8×

Specification

?
\[\begin{array}{l} \\ c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \end{array} \]
(FPCore (c x y)
 :precision binary64
 (* c (log (+ 1.0 (* (- (pow (E) x) 1.0) y)))))
\begin{array}{l}

\\
c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{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 9 alternatives:

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

Initial Program: 42.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \end{array} \]
(FPCore (c x y)
 :precision binary64
 (* c (log (+ 1.0 (* (- (pow (E) x) 1.0) y)))))
\begin{array}{l}

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

Alternative 1: 99.1% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -4.8 \cdot 10^{-92} \lor \neg \left(y \leq 1.2 \cdot 10^{-31}\right):\\ \;\;\;\;\mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\right)\\ \end{array} \end{array} \]
(FPCore (c x y)
 :precision binary64
 (if (or (<= y -4.8e-92) (not (<= y 1.2e-31)))
   (* (log1p (* (expm1 x) y)) c)
   (* (* c y) (expm1 x))))
double code(double c, double x, double y) {
	double tmp;
	if ((y <= -4.8e-92) || !(y <= 1.2e-31)) {
		tmp = log1p((expm1(x) * y)) * c;
	} else {
		tmp = (c * y) * expm1(x);
	}
	return tmp;
}
public static double code(double c, double x, double y) {
	double tmp;
	if ((y <= -4.8e-92) || !(y <= 1.2e-31)) {
		tmp = Math.log1p((Math.expm1(x) * y)) * c;
	} else {
		tmp = (c * y) * Math.expm1(x);
	}
	return tmp;
}
def code(c, x, y):
	tmp = 0
	if (y <= -4.8e-92) or not (y <= 1.2e-31):
		tmp = math.log1p((math.expm1(x) * y)) * c
	else:
		tmp = (c * y) * math.expm1(x)
	return tmp
function code(c, x, y)
	tmp = 0.0
	if ((y <= -4.8e-92) || !(y <= 1.2e-31))
		tmp = Float64(log1p(Float64(expm1(x) * y)) * c);
	else
		tmp = Float64(Float64(c * y) * expm1(x));
	end
	return tmp
end
code[c_, x_, y_] := If[Or[LessEqual[y, -4.8e-92], N[Not[LessEqual[y, 1.2e-31]], $MachinePrecision]], N[(N[Log[1 + N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], N[(N[(c * y), $MachinePrecision] * N[(Exp[x] - 1), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -4.8 \cdot 10^{-92} \lor \neg \left(y \leq 1.2 \cdot 10^{-31}\right):\\
\;\;\;\;\mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -4.8000000000000002e-92 or 1.2e-31 < y

    1. Initial program 36.3%

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

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

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

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

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

        \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \cdot y\right) \]
      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 rewrites99.0%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
    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 rewrites99.0%

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

      if -4.8000000000000002e-92 < y < 1.2e-31

      1. Initial program 40.6%

        \[c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \]
      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-*.f6499.8

          \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
      5. Applied rewrites99.8%

        \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]
    7. Recombined 2 regimes into one program.
    8. Final simplification99.4%

      \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -4.8 \cdot 10^{-92} \lor \neg \left(y \leq 1.2 \cdot 10^{-31}\right):\\ \;\;\;\;\mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\right)\\ \end{array} \]
    9. Add Preprocessing

    Alternative 2: 83.0% accurate, 1.0× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;{\mathsf{E}\left(\right)}^{x} - 1 \leq -1 \cdot 10^{-12}:\\ \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \end{array} \end{array} \]
    (FPCore (c x y)
     :precision binary64
     (if (<= (- (pow (E) x) 1.0) -1e-12)
       (* (* (expm1 x) y) c)
       (* (log1p (* x y)) c)))
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;{\mathsf{E}\left(\right)}^{x} - 1 \leq -1 \cdot 10^{-12}:\\
    \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\
    
    \mathbf{else}:\\
    \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (-.f64 (pow.f64 (E.f64) x) #s(literal 1 binary64)) < -9.9999999999999998e-13

      1. Initial program 41.8%

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

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

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

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

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

          \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \cdot y\right) \]
        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 rewrites100.0%

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

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

          \[\leadsto \left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c \]
        2. *-rgt-identityN/A

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

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

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

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

          \[\leadsto \left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c \]
        7. lift-*.f6471.0

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

          \[\leadsto \left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c \]
        9. *-rgt-identity71.0

          \[\leadsto \left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c \]
      7. Applied rewrites71.0%

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

      if -9.9999999999999998e-13 < (-.f64 (pow.f64 (E.f64) x) #s(literal 1 binary64))

      1. Initial program 37.0%

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

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

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

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

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

          \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \cdot y\right) \]
        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 rewrites89.4%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
      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 rewrites88.5%

          \[\leadsto \mathsf{log1p}\left(\color{blue}{x} \cdot y\right) \cdot c \]
      7. Recombined 2 regimes into one program.
      8. Add Preprocessing

      Alternative 3: 90.3% accurate, 1.5× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -70:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 2 \cdot 10^{+23}:\\ \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \end{array} \]
      (FPCore (c x y)
       :precision binary64
       (if (<= y -70.0)
         (* (log1p (* x y)) c)
         (if (<= y 2e+23)
           (* (* c y) (expm1 x))
           (*
            (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 <= -70.0) {
      		tmp = log1p((x * y)) * c;
      	} else if (y <= 2e+23) {
      		tmp = (c * y) * expm1(x);
      	} 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 <= -70.0)
      		tmp = Float64(log1p(Float64(x * y)) * c);
      	elseif (y <= 2e+23)
      		tmp = Float64(Float64(c * y) * expm1(x));
      	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, -70.0], N[(N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], If[LessEqual[y, 2e+23], N[(N[(c * y), $MachinePrecision] * N[(Exp[x] - 1), $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 -70:\\
      \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\
      
      \mathbf{elif}\;y \leq 2 \cdot 10^{+23}:\\
      \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\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 < -70

        1. Initial program 47.7%

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

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

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

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

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

            \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \cdot y\right) \]
          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 rewrites99.8%

          \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
        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 rewrites64.1%

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

          if -70 < y < 1.9999999999999998e23

          1. Initial program 38.0%

            \[c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \]
          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-*.f6499.4

              \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
          5. Applied rewrites99.4%

            \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]

          if 1.9999999999999998e23 < y

          1. Initial program 23.5%

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

            \[\leadsto c \cdot \log \left(1 + \color{blue}{\left(x \cdot \left(\log \mathsf{E}\left(\right) + x \cdot \left(\frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2} + x \cdot \left(\frac{1}{24} \cdot \left(x \cdot {\log \mathsf{E}\left(\right)}^{4}\right) + \frac{1}{6} \cdot {\log \mathsf{E}\left(\right)}^{3}\right)\right)\right)\right)} \cdot y\right) \]
          4. Step-by-step derivation
            1. *-commutativeN/A

              \[\leadsto c \cdot \log \left(1 + \left(\left(\log \mathsf{E}\left(\right) + x \cdot \left(\frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2} + x \cdot \left(\frac{1}{24} \cdot \left(x \cdot {\log \mathsf{E}\left(\right)}^{4}\right) + \frac{1}{6} \cdot {\log \mathsf{E}\left(\right)}^{3}\right)\right)\right) \cdot \color{blue}{x}\right) \cdot y\right) \]
            2. lower-*.f64N/A

              \[\leadsto c \cdot \log \left(1 + \left(\left(\log \mathsf{E}\left(\right) + x \cdot \left(\frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2} + x \cdot \left(\frac{1}{24} \cdot \left(x \cdot {\log \mathsf{E}\left(\right)}^{4}\right) + \frac{1}{6} \cdot {\log \mathsf{E}\left(\right)}^{3}\right)\right)\right) \cdot \color{blue}{x}\right) \cdot y\right) \]
          5. Applied rewrites48.4%

            \[\leadsto c \cdot \log \left(1 + \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664 \cdot x, 1, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right)} \cdot y\right) \]
          6. Step-by-step derivation
            1. lift-*.f64N/A

              \[\leadsto \color{blue}{c \cdot \log \left(1 + \left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{24} \cdot x, 1, \frac{1}{6}\right), x, \frac{1}{2}\right), x, 1\right) \cdot x\right) \cdot y\right)} \]
            2. *-commutativeN/A

              \[\leadsto \color{blue}{\log \left(1 + \left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{24} \cdot x, 1, \frac{1}{6}\right), x, \frac{1}{2}\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c} \]
            3. lower-*.f6448.4

              \[\leadsto \color{blue}{\log \left(1 + \left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664 \cdot x, 1, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c} \]
          7. Applied rewrites94.7%

            \[\leadsto \color{blue}{\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c} \]
        7. Recombined 3 regimes into one program.
        8. Final simplification90.5%

          \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -70:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 2 \cdot 10^{+23}:\\ \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \]
        9. Add Preprocessing

        Alternative 4: 90.3% accurate, 1.6× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -70:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 2 \cdot 10^{+23}:\\ \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \end{array} \]
        (FPCore (c x y)
         :precision binary64
         (if (<= y -70.0)
           (* (log1p (* x y)) c)
           (if (<= y 2e+23)
             (* (* c y) (expm1 x))
             (* (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 <= -70.0) {
        		tmp = log1p((x * y)) * c;
        	} else if (y <= 2e+23) {
        		tmp = (c * y) * expm1(x);
        	} 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 <= -70.0)
        		tmp = Float64(log1p(Float64(x * y)) * c);
        	elseif (y <= 2e+23)
        		tmp = Float64(Float64(c * y) * expm1(x));
        	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, -70.0], N[(N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], If[LessEqual[y, 2e+23], N[(N[(c * y), $MachinePrecision] * N[(Exp[x] - 1), $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 -70:\\
        \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\
        
        \mathbf{elif}\;y \leq 2 \cdot 10^{+23}:\\
        \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\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 < -70

          1. Initial program 47.7%

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

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

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

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

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

              \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \cdot y\right) \]
            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 rewrites99.8%

            \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
          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 rewrites64.1%

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

            if -70 < y < 1.9999999999999998e23

            1. Initial program 38.0%

              \[c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \]
            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-*.f6499.4

                \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
            5. Applied rewrites99.4%

              \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]

            if 1.9999999999999998e23 < y

            1. Initial program 23.5%

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

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

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

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

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

                \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \cdot y\right) \]
              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 rewrites96.6%

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

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

                \[\leadsto \mathsf{log1p}\left(\left(\left(1 + x \cdot \left(\frac{1}{2} + \frac{1}{6} \cdot x\right)\right) \cdot \color{blue}{x}\right) \cdot y\right) \cdot c \]
              2. metadata-evalN/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(1 + x \cdot \left(\frac{1}{2} \cdot 1 + \frac{1}{6} \cdot x\right)\right) \cdot x\right) \cdot y\right) \cdot c \]
              3. metadata-evalN/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(1 + x \cdot \left(\frac{1}{2} \cdot {1}^{2} + \frac{1}{6} \cdot x\right)\right) \cdot x\right) \cdot y\right) \cdot c \]
              4. log-EN/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(1 + x \cdot \left(\frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2} + \frac{1}{6} \cdot x\right)\right) \cdot x\right) \cdot y\right) \cdot c \]
              5. *-rgt-identityN/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(1 + x \cdot \left(\frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2} + \frac{1}{6} \cdot \left(x \cdot 1\right)\right)\right) \cdot x\right) \cdot y\right) \cdot c \]
              6. metadata-evalN/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(1 + x \cdot \left(\frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2} + \frac{1}{6} \cdot \left(x \cdot {1}^{3}\right)\right)\right) \cdot x\right) \cdot y\right) \cdot c \]
              7. log-EN/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(1 + x \cdot \left(\frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2} + \frac{1}{6} \cdot \left(x \cdot {\log \mathsf{E}\left(\right)}^{3}\right)\right)\right) \cdot x\right) \cdot y\right) \cdot c \]
              8. +-commutativeN/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(1 + x \cdot \left(\frac{1}{6} \cdot \left(x \cdot {\log \mathsf{E}\left(\right)}^{3}\right) + \frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2}\right)\right) \cdot x\right) \cdot y\right) \cdot c \]
              9. log-EN/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(\log \mathsf{E}\left(\right) + x \cdot \left(\frac{1}{6} \cdot \left(x \cdot {\log \mathsf{E}\left(\right)}^{3}\right) + \frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2}\right)\right) \cdot x\right) \cdot y\right) \cdot c \]
              10. lower-*.f64N/A

                \[\leadsto \mathsf{log1p}\left(\left(\left(\log \mathsf{E}\left(\right) + x \cdot \left(\frac{1}{6} \cdot \left(x \cdot {\log \mathsf{E}\left(\right)}^{3}\right) + \frac{1}{2} \cdot {\log \mathsf{E}\left(\right)}^{2}\right)\right) \cdot \color{blue}{x}\right) \cdot y\right) \cdot c \]
            7. Applied rewrites94.6%

              \[\leadsto \mathsf{log1p}\left(\color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.5\right), x, 1\right) \cdot x\right)} \cdot y\right) \cdot c \]
          7. Recombined 3 regimes into one program.
          8. Final simplification90.5%

            \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -70:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 2 \cdot 10^{+23}:\\ \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \]
          9. Add Preprocessing

          Alternative 5: 90.2% accurate, 1.6× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -70:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 2 \cdot 10^{+23}:\\ \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \end{array} \]
          (FPCore (c x y)
           :precision binary64
           (if (<= y -70.0)
             (* (log1p (* x y)) c)
             (if (<= y 2e+23)
               (* (* c y) (expm1 x))
               (* (log1p (* (* (fma 0.5 x 1.0) x) y)) c))))
          double code(double c, double x, double y) {
          	double tmp;
          	if (y <= -70.0) {
          		tmp = log1p((x * y)) * c;
          	} else if (y <= 2e+23) {
          		tmp = (c * y) * expm1(x);
          	} else {
          		tmp = log1p(((fma(0.5, x, 1.0) * x) * y)) * c;
          	}
          	return tmp;
          }
          
          function code(c, x, y)
          	tmp = 0.0
          	if (y <= -70.0)
          		tmp = Float64(log1p(Float64(x * y)) * c);
          	elseif (y <= 2e+23)
          		tmp = Float64(Float64(c * y) * expm1(x));
          	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, -70.0], N[(N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], If[LessEqual[y, 2e+23], N[(N[(c * y), $MachinePrecision] * N[(Exp[x] - 1), $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 -70:\\
          \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\
          
          \mathbf{elif}\;y \leq 2 \cdot 10^{+23}:\\
          \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\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 < -70

            1. Initial program 47.7%

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

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

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

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

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

                \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \cdot y\right) \]
              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 rewrites99.8%

              \[\leadsto \color{blue}{\mathsf{log1p}\left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c} \]
            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 rewrites64.1%

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

              if -70 < y < 1.9999999999999998e23

              1. Initial program 38.0%

                \[c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \]
              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-*.f6499.4

                  \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
              5. Applied rewrites99.4%

                \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]

              if 1.9999999999999998e23 < y

              1. Initial program 23.5%

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

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

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

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

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

                  \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \cdot y\right) \]
                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 rewrites96.6%

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

                \[\leadsto \mathsf{log1p}\left(\color{blue}{\left(x \cdot \left(1 + \frac{1}{2} \cdot x\right)\right)} \cdot y\right) \cdot c \]
              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.f6494.6

                  \[\leadsto \mathsf{log1p}\left(\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right) \cdot y\right) \cdot c \]
              7. Applied rewrites94.6%

                \[\leadsto \mathsf{log1p}\left(\color{blue}{\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right)} \cdot y\right) \cdot c \]
            7. Recombined 3 regimes into one program.
            8. Final simplification90.5%

              \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -70:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{elif}\;y \leq 2 \cdot 10^{+23}:\\ \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \]
            9. Add Preprocessing

            Alternative 6: 90.1% accurate, 1.8× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -70 \lor \neg \left(y \leq 2 \cdot 10^{+23}\right):\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\right)\\ \end{array} \end{array} \]
            (FPCore (c x y)
             :precision binary64
             (if (or (<= y -70.0) (not (<= y 2e+23)))
               (* (log1p (* x y)) c)
               (* (* c y) (expm1 x))))
            double code(double c, double x, double y) {
            	double tmp;
            	if ((y <= -70.0) || !(y <= 2e+23)) {
            		tmp = log1p((x * y)) * c;
            	} else {
            		tmp = (c * y) * expm1(x);
            	}
            	return tmp;
            }
            
            public static double code(double c, double x, double y) {
            	double tmp;
            	if ((y <= -70.0) || !(y <= 2e+23)) {
            		tmp = Math.log1p((x * y)) * c;
            	} else {
            		tmp = (c * y) * Math.expm1(x);
            	}
            	return tmp;
            }
            
            def code(c, x, y):
            	tmp = 0
            	if (y <= -70.0) or not (y <= 2e+23):
            		tmp = math.log1p((x * y)) * c
            	else:
            		tmp = (c * y) * math.expm1(x)
            	return tmp
            
            function code(c, x, y)
            	tmp = 0.0
            	if ((y <= -70.0) || !(y <= 2e+23))
            		tmp = Float64(log1p(Float64(x * y)) * c);
            	else
            		tmp = Float64(Float64(c * y) * expm1(x));
            	end
            	return tmp
            end
            
            code[c_, x_, y_] := If[Or[LessEqual[y, -70.0], N[Not[LessEqual[y, 2e+23]], $MachinePrecision]], N[(N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], N[(N[(c * y), $MachinePrecision] * N[(Exp[x] - 1), $MachinePrecision]), $MachinePrecision]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;y \leq -70 \lor \neg \left(y \leq 2 \cdot 10^{+23}\right):\\
            \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\
            
            \mathbf{else}:\\
            \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if y < -70 or 1.9999999999999998e23 < y

              1. Initial program 39.3%

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

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

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

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

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

                  \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \cdot y\right) \]
                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 rewrites98.7%

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

                \[\leadsto \mathsf{log1p}\left(\color{blue}{x} \cdot y\right) \cdot c \]
              6. Step-by-step derivation
                1. Applied rewrites74.6%

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

                if -70 < y < 1.9999999999999998e23

                1. Initial program 38.0%

                  \[c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \]
                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-*.f6499.4

                    \[\leadsto \left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right) \]
                5. Applied rewrites99.4%

                  \[\leadsto \color{blue}{\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x \cdot 1\right)} \]
              7. Recombined 2 regimes into one program.
              8. Final simplification90.5%

                \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -70 \lor \neg \left(y \leq 2 \cdot 10^{+23}\right):\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\left(c \cdot y\right) \cdot \mathsf{expm1}\left(x\right)\\ \end{array} \]
              9. Add Preprocessing

              Alternative 7: 76.8% accurate, 1.9× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -2.5 \cdot 10^{-99}:\\ \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\left(c \cdot x\right) \cdot y\\ \end{array} \end{array} \]
              (FPCore (c x y)
               :precision binary64
               (if (<= x -2.5e-99) (* (* (expm1 x) y) c) (* (* c x) y)))
              double code(double c, double x, double y) {
              	double tmp;
              	if (x <= -2.5e-99) {
              		tmp = (expm1(x) * y) * c;
              	} else {
              		tmp = (c * x) * y;
              	}
              	return tmp;
              }
              
              public static double code(double c, double x, double y) {
              	double tmp;
              	if (x <= -2.5e-99) {
              		tmp = (Math.expm1(x) * y) * c;
              	} else {
              		tmp = (c * x) * y;
              	}
              	return tmp;
              }
              
              def code(c, x, y):
              	tmp = 0
              	if x <= -2.5e-99:
              		tmp = (math.expm1(x) * y) * c
              	else:
              		tmp = (c * x) * y
              	return tmp
              
              function code(c, x, y)
              	tmp = 0.0
              	if (x <= -2.5e-99)
              		tmp = Float64(Float64(expm1(x) * y) * c);
              	else
              		tmp = Float64(Float64(c * x) * y);
              	end
              	return tmp
              end
              
              code[c_, x_, y_] := If[LessEqual[x, -2.5e-99], N[(N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision] * c), $MachinePrecision], N[(N[(c * x), $MachinePrecision] * y), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;x \leq -2.5 \cdot 10^{-99}:\\
              \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(c \cdot x\right) \cdot y\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if x < -2.49999999999999985e-99

                1. Initial program 40.8%

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

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

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

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

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

                    \[\leadsto c \cdot \log \left(1 + \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)} \cdot y\right) \]
                  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 rewrites99.9%

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

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

                    \[\leadsto \left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c \]
                  2. *-rgt-identityN/A

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

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

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

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

                    \[\leadsto \left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c \]
                  7. lift-*.f6474.8

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

                    \[\leadsto \left(\mathsf{expm1}\left(x \cdot 1\right) \cdot y\right) \cdot c \]
                  9. *-rgt-identity74.8

                    \[\leadsto \left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c \]
                7. Applied rewrites74.8%

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

                if -2.49999999999999985e-99 < x

                1. Initial program 36.9%

                  \[c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \]
                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-*.f6482.8

                    \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \color{blue}{1}\right) \]
                5. Applied rewrites82.8%

                  \[\leadsto \color{blue}{\left(c \cdot x\right) \cdot \left(y \cdot 1\right)} \]
                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-identity82.8

                    \[\leadsto \left(c \cdot x\right) \cdot y \]
                7. Applied rewrites82.8%

                  \[\leadsto \left(c \cdot x\right) \cdot \color{blue}{y} \]
              3. Recombined 2 regimes into one program.
              4. Add Preprocessing

              Alternative 8: 63.8% accurate, 12.8× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;c \leq 10^{-19}:\\ \;\;\;\;\left(c \cdot y\right) \cdot x\\ \mathbf{else}:\\ \;\;\;\;\left(c \cdot x\right) \cdot y\\ \end{array} \end{array} \]
              (FPCore (c x y)
               :precision binary64
               (if (<= c 1e-19) (* (* c y) x) (* (* c x) y)))
              double code(double c, double x, double y) {
              	double tmp;
              	if (c <= 1e-19) {
              		tmp = (c * y) * x;
              	} else {
              		tmp = (c * x) * y;
              	}
              	return tmp;
              }
              
              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
                  real(8) :: tmp
                  if (c <= 1d-19) then
                      tmp = (c * y) * x
                  else
                      tmp = (c * x) * y
                  end if
                  code = tmp
              end function
              
              public static double code(double c, double x, double y) {
              	double tmp;
              	if (c <= 1e-19) {
              		tmp = (c * y) * x;
              	} else {
              		tmp = (c * x) * y;
              	}
              	return tmp;
              }
              
              def code(c, x, y):
              	tmp = 0
              	if c <= 1e-19:
              		tmp = (c * y) * x
              	else:
              		tmp = (c * x) * y
              	return tmp
              
              function code(c, x, y)
              	tmp = 0.0
              	if (c <= 1e-19)
              		tmp = Float64(Float64(c * y) * x);
              	else
              		tmp = Float64(Float64(c * x) * y);
              	end
              	return tmp
              end
              
              function tmp_2 = code(c, x, y)
              	tmp = 0.0;
              	if (c <= 1e-19)
              		tmp = (c * y) * x;
              	else
              		tmp = (c * x) * y;
              	end
              	tmp_2 = tmp;
              end
              
              code[c_, x_, y_] := If[LessEqual[c, 1e-19], N[(N[(c * y), $MachinePrecision] * x), $MachinePrecision], N[(N[(c * x), $MachinePrecision] * y), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;c \leq 10^{-19}:\\
              \;\;\;\;\left(c \cdot y\right) \cdot x\\
              
              \mathbf{else}:\\
              \;\;\;\;\left(c \cdot x\right) \cdot y\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if c < 9.9999999999999998e-20

                1. Initial program 44.8%

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

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

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

                    \[\leadsto \left(\frac{1}{2} \cdot \left(c \cdot \left(x \cdot \left(-1 \cdot \left({y}^{2} \cdot {\log \mathsf{E}\left(\right)}^{2}\right) + y \cdot {\log \mathsf{E}\left(\right)}^{2}\right)\right)\right) + c \cdot \left(y \cdot \log \mathsf{E}\left(\right)\right)\right) \cdot \color{blue}{x} \]
                5. Applied rewrites56.2%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(0.5 \cdot c, \mathsf{fma}\left(y, 1, -\left(y \cdot y\right) \cdot 1\right) \cdot x, \left(c \cdot y\right) \cdot 1\right) \cdot x} \]
                6. Taylor expanded in x around 0

                  \[\leadsto \left(c \cdot y\right) \cdot x \]
                7. Step-by-step derivation
                  1. lift-*.f6460.9

                    \[\leadsto \left(c \cdot y\right) \cdot x \]
                8. Applied rewrites60.9%

                  \[\leadsto \left(c \cdot y\right) \cdot x \]

                if 9.9999999999999998e-20 < c

                1. Initial program 19.7%

                  \[c \cdot \log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \]
                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-*.f6465.0

                    \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \color{blue}{1}\right) \]
                5. Applied rewrites65.0%

                  \[\leadsto \color{blue}{\left(c \cdot x\right) \cdot \left(y \cdot 1\right)} \]
                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-identity65.0

                    \[\leadsto \left(c \cdot x\right) \cdot y \]
                7. Applied rewrites65.0%

                  \[\leadsto \left(c \cdot x\right) \cdot \color{blue}{y} \]
              3. Recombined 2 regimes into one program.
              4. Add Preprocessing

              Alternative 9: 62.4% 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 38.5%

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

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

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

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

                \[\leadsto \color{blue}{\mathsf{fma}\left(0.5 \cdot c, \mathsf{fma}\left(y, 1, -\left(y \cdot y\right) \cdot 1\right) \cdot x, \left(c \cdot y\right) \cdot 1\right) \cdot x} \]
              6. Taylor expanded in x around 0

                \[\leadsto \left(c \cdot y\right) \cdot x \]
              7. Step-by-step derivation
                1. lift-*.f6459.4

                  \[\leadsto \left(c \cdot y\right) \cdot x \]
              8. Applied rewrites59.4%

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

              Developer Target 1: 93.5% 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 2025037 
              (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)))))