Logarithmic Transform

Percentage Accurate: 41.9% → 99.0%
Time: 14.1s
Alternatives: 12
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 12 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: 41.9% 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: 99.0% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -0.000205:\\ \;\;\;\;c \cdot \mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right)\\ \mathbf{elif}\;y \leq 3.8 \cdot 10^{+15}:\\ \;\;\;\;\left(\mathsf{fma}\left(-0.5 \cdot {\left(\mathsf{expm1}\left(x\right)\right)}^{2}, y, \mathsf{expm1}\left(x\right)\right) \cdot c\right) \cdot y\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \end{array} \end{array} \]
(FPCore (c x y)
 :precision binary64
 (if (<= y -0.000205)
   (* c (log1p (* (expm1 x) y)))
   (if (<= y 3.8e+15)
     (* (* (fma (* -0.5 (pow (expm1 x) 2.0)) y (expm1 x)) c) y)
     (* (log1p (* x y)) c))))
double code(double c, double x, double y) {
	double tmp;
	if (y <= -0.000205) {
		tmp = c * log1p((expm1(x) * y));
	} else if (y <= 3.8e+15) {
		tmp = (fma((-0.5 * pow(expm1(x), 2.0)), y, expm1(x)) * c) * y;
	} else {
		tmp = log1p((x * y)) * c;
	}
	return tmp;
}
function code(c, x, y)
	tmp = 0.0
	if (y <= -0.000205)
		tmp = Float64(c * log1p(Float64(expm1(x) * y)));
	elseif (y <= 3.8e+15)
		tmp = Float64(Float64(fma(Float64(-0.5 * (expm1(x) ^ 2.0)), y, expm1(x)) * c) * y);
	else
		tmp = Float64(log1p(Float64(x * y)) * c);
	end
	return tmp
end
code[c_, x_, y_] := If[LessEqual[y, -0.000205], N[(c * N[Log[1 + N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 3.8e+15], N[(N[(N[(N[(-0.5 * N[Power[N[(Exp[x] - 1), $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] * y + N[(Exp[x] - 1), $MachinePrecision]), $MachinePrecision] * c), $MachinePrecision] * y), $MachinePrecision], N[(N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -0.000205:\\
\;\;\;\;c \cdot \mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right)\\

\mathbf{elif}\;y \leq 3.8 \cdot 10^{+15}:\\
\;\;\;\;\left(\mathsf{fma}\left(-0.5 \cdot {\left(\mathsf{expm1}\left(x\right)\right)}^{2}, y, \mathsf{expm1}\left(x\right)\right) \cdot c\right) \cdot y\\

\mathbf{else}:\\
\;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < -2.05e-4

    1. Initial program 51.1%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6451.1

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6451.3

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6451.3

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6499.7

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites99.7%

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

    if -2.05e-4 < y < 3.8e15

    1. Initial program 35.0%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6435.0

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6460.2

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6460.2

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6489.7

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites89.7%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
    5. Step-by-step derivation
      1. lift-log1p.f64N/A

        \[\leadsto \color{blue}{\log \left(1 + y \cdot \mathsf{expm1}\left(x\right)\right)} \cdot c \]
      2. flip-+N/A

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

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

        \[\leadsto \color{blue}{\left(\log \left(1 \cdot 1 - \left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right)\right) - \log \left(1 - y \cdot \mathsf{expm1}\left(x\right)\right)\right)} \cdot c \]
      5. metadata-evalN/A

        \[\leadsto \left(\log \left(\color{blue}{1} - \left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right)\right) - \log \left(1 - y \cdot \mathsf{expm1}\left(x\right)\right)\right) \cdot c \]
      6. sub-negN/A

        \[\leadsto \left(\log \color{blue}{\left(1 + \left(\mathsf{neg}\left(\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right)\right)\right)\right)} - \log \left(1 - y \cdot \mathsf{expm1}\left(x\right)\right)\right) \cdot c \]
      7. lower-log1p.f64N/A

        \[\leadsto \left(\color{blue}{\mathsf{log1p}\left(\mathsf{neg}\left(\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right)\right)\right)} - \log \left(1 - y \cdot \mathsf{expm1}\left(x\right)\right)\right) \cdot c \]
      8. lower-neg.f64N/A

        \[\leadsto \left(\mathsf{log1p}\left(\color{blue}{-\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right)}\right) - \log \left(1 - y \cdot \mathsf{expm1}\left(x\right)\right)\right) \cdot c \]
      9. pow2N/A

        \[\leadsto \left(\mathsf{log1p}\left(-\color{blue}{{\left(y \cdot \mathsf{expm1}\left(x\right)\right)}^{2}}\right) - \log \left(1 - y \cdot \mathsf{expm1}\left(x\right)\right)\right) \cdot c \]
      10. lower-pow.f64N/A

        \[\leadsto \left(\mathsf{log1p}\left(-\color{blue}{{\left(y \cdot \mathsf{expm1}\left(x\right)\right)}^{2}}\right) - \log \left(1 - y \cdot \mathsf{expm1}\left(x\right)\right)\right) \cdot c \]
      11. lift-*.f64N/A

        \[\leadsto \left(\mathsf{log1p}\left(-{\color{blue}{\left(y \cdot \mathsf{expm1}\left(x\right)\right)}}^{2}\right) - \log \left(1 - y \cdot \mathsf{expm1}\left(x\right)\right)\right) \cdot c \]
      12. *-commutativeN/A

        \[\leadsto \left(\mathsf{log1p}\left(-{\color{blue}{\left(\mathsf{expm1}\left(x\right) \cdot y\right)}}^{2}\right) - \log \left(1 - y \cdot \mathsf{expm1}\left(x\right)\right)\right) \cdot c \]
      13. lower-*.f64N/A

        \[\leadsto \left(\mathsf{log1p}\left(-{\color{blue}{\left(\mathsf{expm1}\left(x\right) \cdot y\right)}}^{2}\right) - \log \left(1 - y \cdot \mathsf{expm1}\left(x\right)\right)\right) \cdot c \]
      14. lift-*.f64N/A

        \[\leadsto \left(\mathsf{log1p}\left(-{\left(\mathsf{expm1}\left(x\right) \cdot y\right)}^{2}\right) - \log \left(1 - \color{blue}{y \cdot \mathsf{expm1}\left(x\right)}\right)\right) \cdot c \]
      15. cancel-sign-sub-invN/A

        \[\leadsto \left(\mathsf{log1p}\left(-{\left(\mathsf{expm1}\left(x\right) \cdot y\right)}^{2}\right) - \log \color{blue}{\left(1 + \left(\mathsf{neg}\left(y\right)\right) \cdot \mathsf{expm1}\left(x\right)\right)}\right) \cdot c \]
    6. Applied rewrites89.7%

      \[\leadsto \color{blue}{\left(\mathsf{log1p}\left(-{\left(\mathsf{expm1}\left(x\right) \cdot y\right)}^{2}\right) - \mathsf{log1p}\left(\left(-y\right) \cdot \mathsf{expm1}\left(x\right)\right)\right)} \cdot c \]
    7. Taylor expanded in y around 0

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

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

        \[\leadsto \color{blue}{\left(c \cdot \left(y \cdot \left(-1 \cdot {\left(e^{x} - 1\right)}^{2} - \frac{-1}{2} \cdot {\left(e^{x} - 1\right)}^{2}\right)\right) + c \cdot \left(e^{x} - 1\right)\right) \cdot y} \]
    9. Applied rewrites99.2%

      \[\leadsto \color{blue}{\left(c \cdot \mathsf{fma}\left({\left(\mathsf{expm1}\left(x\right)\right)}^{2} \cdot -0.5, y, \mathsf{expm1}\left(x\right)\right)\right) \cdot y} \]

    if 3.8e15 < y

    1. Initial program 17.7%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6417.7

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6417.7

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6417.7

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6499.6

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites99.6%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
    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. lower-*.f6499.6

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

      \[\leadsto \mathsf{log1p}\left(\color{blue}{x \cdot y}\right) \cdot c \]
  3. Recombined 3 regimes into one program.
  4. Final simplification99.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -0.000205:\\ \;\;\;\;c \cdot \mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right)\\ \mathbf{elif}\;y \leq 3.8 \cdot 10^{+15}:\\ \;\;\;\;\left(\mathsf{fma}\left(-0.5 \cdot {\left(\mathsf{expm1}\left(x\right)\right)}^{2}, y, \mathsf{expm1}\left(x\right)\right) \cdot c\right) \cdot y\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 83.2% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;{\mathsf{E}\left(\right)}^{x} \leq 0:\\ \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \end{array} \]
(FPCore (c x y)
 :precision binary64
 (if (<= (pow (E) x) 0.0)
   (* (* (expm1 x) y) c)
   (*
    (log1p
     (*
      (*
       (fma (fma (fma 0.041666666666666664 x 0.16666666666666666) x 0.5) x 1.0)
       x)
      y))
    c)))
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;{\mathsf{E}\left(\right)}^{x} \leq 0:\\
\;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\

\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 2 regimes
  2. if (pow.f64 (E.f64) x) < 0.0

    1. Initial program 50.5%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6450.5

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6499.8

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6499.8

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6499.8

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites99.8%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
    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. *-commutativeN/A

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

        \[\leadsto \color{blue}{\left(\left(e^{x} - 1\right) \cdot y\right)} \cdot c \]
      3. lower-expm1.f6459.7

        \[\leadsto \left(\color{blue}{\mathsf{expm1}\left(x\right)} \cdot y\right) \cdot c \]
    7. Applied rewrites59.7%

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

    if 0.0 < (pow.f64 (E.f64) x)

    1. Initial program 30.8%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6430.8

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6431.8

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6431.8

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6491.9

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites91.9%

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

      \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left(x \cdot \left(1 + x \cdot \left(\frac{1}{2} + x \cdot \left(\frac{1}{6} + \frac{1}{24} \cdot x\right)\right)\right)\right)}\right) \cdot c \]
    6. Applied rewrites91.9%

      \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right)}\right) \cdot c \]
  3. Recombined 2 regimes into one program.
  4. Final simplification83.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;{\mathsf{E}\left(\right)}^{x} \leq 0:\\ \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x, 0.16666666666666666\right), x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 93.3% 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}
Derivation
  1. Initial program 36.2%

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

      \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
    3. lower-*.f6436.2

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

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

      \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
    6. lower-log1p.f6450.4

      \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
    7. lift-*.f64N/A

      \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
    8. *-commutativeN/A

      \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
    9. lower-*.f6450.4

      \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
    10. lift--.f64N/A

      \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
    11. lift-pow.f64N/A

      \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
    12. pow-to-expN/A

      \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
    13. lift-E.f64N/A

      \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
    14. log-EN/A

      \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
    15. *-lft-identityN/A

      \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
    16. lower-expm1.f6494.0

      \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
  4. Applied rewrites94.0%

    \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
  5. Final simplification94.0%

    \[\leadsto c \cdot \mathsf{log1p}\left(\mathsf{expm1}\left(x\right) \cdot y\right) \]
  6. Add Preprocessing

Alternative 4: 85.4% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -0.5:\\ \;\;\;\;\mathsf{log1p}\left(\frac{y}{\frac{\mathsf{fma}\left(-0.5, x, 1\right)}{x}}\right) \cdot c\\ \mathbf{elif}\;y \leq 8 \cdot 10^{-19}:\\ \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \end{array} \end{array} \]
(FPCore (c x y)
 :precision binary64
 (if (<= y -0.5)
   (* (log1p (/ y (/ (fma -0.5 x 1.0) x))) c)
   (if (<= y 8e-19) (* (* (expm1 x) y) c) (* (log1p (* x y)) c))))
double code(double c, double x, double y) {
	double tmp;
	if (y <= -0.5) {
		tmp = log1p((y / (fma(-0.5, x, 1.0) / x))) * c;
	} else if (y <= 8e-19) {
		tmp = (expm1(x) * y) * c;
	} else {
		tmp = log1p((x * y)) * c;
	}
	return tmp;
}
function code(c, x, y)
	tmp = 0.0
	if (y <= -0.5)
		tmp = Float64(log1p(Float64(y / Float64(fma(-0.5, x, 1.0) / x))) * c);
	elseif (y <= 8e-19)
		tmp = Float64(Float64(expm1(x) * y) * c);
	else
		tmp = Float64(log1p(Float64(x * y)) * c);
	end
	return tmp
end
code[c_, x_, y_] := If[LessEqual[y, -0.5], N[(N[Log[1 + N[(y / N[(N[(-0.5 * x + 1.0), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision], If[LessEqual[y, 8e-19], N[(N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision] * c), $MachinePrecision], N[(N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -0.5:\\
\;\;\;\;\mathsf{log1p}\left(\frac{y}{\frac{\mathsf{fma}\left(-0.5, x, 1\right)}{x}}\right) \cdot c\\

\mathbf{elif}\;y \leq 8 \cdot 10^{-19}:\\
\;\;\;\;\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 3 regimes
  2. if y < -0.5

    1. Initial program 50.5%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6450.5

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6450.5

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6450.5

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6499.7

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites99.7%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
    5. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \mathsf{expm1}\left(x\right)}\right) \cdot c \]
      2. lift-expm1.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left(e^{x} - 1\right)}\right) \cdot c \]
      3. flip3--N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\frac{{\left(e^{x}\right)}^{3} - {1}^{3}}{e^{x} \cdot e^{x} + \left(1 \cdot 1 + e^{x} \cdot 1\right)}}\right) \cdot c \]
      4. clear-numN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\frac{1}{\frac{e^{x} \cdot e^{x} + \left(1 \cdot 1 + e^{x} \cdot 1\right)}{{\left(e^{x}\right)}^{3} - {1}^{3}}}}\right) \cdot c \]
      5. un-div-invN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\frac{y}{\frac{e^{x} \cdot e^{x} + \left(1 \cdot 1 + e^{x} \cdot 1\right)}{{\left(e^{x}\right)}^{3} - {1}^{3}}}}\right) \cdot c \]
      6. lower-/.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\frac{y}{\frac{e^{x} \cdot e^{x} + \left(1 \cdot 1 + e^{x} \cdot 1\right)}{{\left(e^{x}\right)}^{3} - {1}^{3}}}}\right) \cdot c \]
      7. clear-numN/A

        \[\leadsto \mathsf{log1p}\left(\frac{y}{\color{blue}{\frac{1}{\frac{{\left(e^{x}\right)}^{3} - {1}^{3}}{e^{x} \cdot e^{x} + \left(1 \cdot 1 + e^{x} \cdot 1\right)}}}}\right) \cdot c \]
      8. flip3--N/A

        \[\leadsto \mathsf{log1p}\left(\frac{y}{\frac{1}{\color{blue}{e^{x} - 1}}}\right) \cdot c \]
      9. lift-expm1.f64N/A

        \[\leadsto \mathsf{log1p}\left(\frac{y}{\frac{1}{\color{blue}{\mathsf{expm1}\left(x\right)}}}\right) \cdot c \]
      10. lower-/.f6499.7

        \[\leadsto \mathsf{log1p}\left(\frac{y}{\color{blue}{\frac{1}{\mathsf{expm1}\left(x\right)}}}\right) \cdot c \]
    6. Applied rewrites99.7%

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

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

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

        \[\leadsto \mathsf{log1p}\left(\frac{y}{\frac{\color{blue}{\frac{-1}{2} \cdot x + 1}}{x}}\right) \cdot c \]
      3. lower-fma.f6468.9

        \[\leadsto \mathsf{log1p}\left(\frac{y}{\frac{\color{blue}{\mathsf{fma}\left(-0.5, x, 1\right)}}{x}}\right) \cdot c \]
    9. Applied rewrites68.9%

      \[\leadsto \mathsf{log1p}\left(\frac{y}{\color{blue}{\frac{\mathsf{fma}\left(-0.5, x, 1\right)}{x}}}\right) \cdot c \]

    if -0.5 < y < 7.9999999999999998e-19

    1. Initial program 35.3%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6435.3

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6462.7

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6462.7

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6488.9

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites88.9%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
    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. *-commutativeN/A

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

        \[\leadsto \color{blue}{\left(\left(e^{x} - 1\right) \cdot y\right)} \cdot c \]
      3. lower-expm1.f6488.1

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

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

    if 7.9999999999999998e-19 < y

    1. Initial program 21.6%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6421.6

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6421.6

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6421.6

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6499.6

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites99.6%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
    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. lower-*.f6499.6

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

      \[\leadsto \mathsf{log1p}\left(\color{blue}{x \cdot y}\right) \cdot c \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 5: 83.1% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -240000:\\ \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \end{array} \]
(FPCore (c x y)
 :precision binary64
 (if (<= x -240000.0)
   (* (* (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 (x <= -240000.0) {
		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 (x <= -240000.0)
		tmp = Float64(Float64(expm1(x) * 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[x, -240000.0], N[(N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision] * c), $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}\;x \leq -240000:\\
\;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\

\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 2 regimes
  2. if x < -2.4e5

    1. Initial program 49.1%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6449.1

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6499.8

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6499.8

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6499.8

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites99.8%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
    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. *-commutativeN/A

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

        \[\leadsto \color{blue}{\left(\left(e^{x} - 1\right) \cdot y\right)} \cdot c \]
      3. lower-expm1.f6459.9

        \[\leadsto \left(\color{blue}{\mathsf{expm1}\left(x\right)} \cdot y\right) \cdot c \]
    7. Applied rewrites59.9%

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

    if -2.4e5 < x

    1. Initial program 31.5%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6431.5

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6432.5

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6432.5

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6491.9

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites91.9%

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

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

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

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

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

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\left(\color{blue}{\left(\frac{1}{2} + \frac{1}{6} \cdot x\right) \cdot x} + 1\right) \cdot x\right)\right) \cdot c \]
      5. lower-fma.f64N/A

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

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\mathsf{fma}\left(\color{blue}{\frac{1}{6} \cdot x + \frac{1}{2}}, x, 1\right) \cdot x\right)\right) \cdot c \]
      7. lower-fma.f6491.5

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(0.16666666666666666, x, 0.5\right)}, x, 1\right) \cdot x\right)\right) \cdot c \]
    7. Applied rewrites91.5%

      \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.5\right), x, 1\right) \cdot x\right)}\right) \cdot c \]
  3. Recombined 2 regimes into one program.
  4. Final simplification83.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -240000:\\ \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x, 0.5\right), x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 83.1% accurate, 1.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -0.00075:\\ \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \end{array} \]
(FPCore (c x y)
 :precision binary64
 (if (<= x -0.00075)
   (* (* (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 (x <= -0.00075) {
		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 (x <= -0.00075)
		tmp = Float64(Float64(expm1(x) * 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[x, -0.00075], N[(N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision] * c), $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}\;x \leq -0.00075:\\
\;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\

\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 2 regimes
  2. if x < -7.5000000000000002e-4

    1. Initial program 50.5%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6450.5

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6499.8

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6499.8

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6499.8

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites99.8%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
    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. *-commutativeN/A

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

        \[\leadsto \color{blue}{\left(\left(e^{x} - 1\right) \cdot y\right)} \cdot c \]
      3. lower-expm1.f6459.7

        \[\leadsto \left(\color{blue}{\mathsf{expm1}\left(x\right)} \cdot y\right) \cdot c \]
    7. Applied rewrites59.7%

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

    if -7.5000000000000002e-4 < x

    1. Initial program 30.8%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6430.8

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6431.8

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6431.8

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6491.9

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites91.9%

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

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

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

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

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{\left(\frac{1}{2} \cdot x + 1\right)} \cdot x\right)\right) \cdot c \]
      4. lower-fma.f6491.5

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{\mathsf{fma}\left(0.5, x, 1\right)} \cdot x\right)\right) \cdot c \]
    7. Applied rewrites91.5%

      \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right)}\right) \cdot c \]
  3. Recombined 2 regimes into one program.
  4. Final simplification82.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -0.00075:\\ \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(\left(\mathsf{fma}\left(0.5, x, 1\right) \cdot x\right) \cdot y\right) \cdot c\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 82.4% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -240000:\\ \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\mathsf{log1p}\left(x \cdot y\right) \cdot c\\ \end{array} \end{array} \]
(FPCore (c x y)
 :precision binary64
 (if (<= x -240000.0) (* (* (expm1 x) y) c) (* (log1p (* x y)) c)))
double code(double c, double x, double y) {
	double tmp;
	if (x <= -240000.0) {
		tmp = (expm1(x) * y) * c;
	} else {
		tmp = log1p((x * y)) * c;
	}
	return tmp;
}
public static double code(double c, double x, double y) {
	double tmp;
	if (x <= -240000.0) {
		tmp = (Math.expm1(x) * y) * c;
	} else {
		tmp = Math.log1p((x * y)) * c;
	}
	return tmp;
}
def code(c, x, y):
	tmp = 0
	if x <= -240000.0:
		tmp = (math.expm1(x) * y) * c
	else:
		tmp = math.log1p((x * y)) * c
	return tmp
function code(c, x, y)
	tmp = 0.0
	if (x <= -240000.0)
		tmp = Float64(Float64(expm1(x) * y) * c);
	else
		tmp = Float64(log1p(Float64(x * y)) * c);
	end
	return tmp
end
code[c_, x_, y_] := If[LessEqual[x, -240000.0], N[(N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision] * c), $MachinePrecision], N[(N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -240000:\\
\;\;\;\;\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 x < -2.4e5

    1. Initial program 49.1%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6449.1

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6499.8

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6499.8

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6499.8

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites99.8%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
    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. *-commutativeN/A

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

        \[\leadsto \color{blue}{\left(\left(e^{x} - 1\right) \cdot y\right)} \cdot c \]
      3. lower-expm1.f6459.9

        \[\leadsto \left(\color{blue}{\mathsf{expm1}\left(x\right)} \cdot y\right) \cdot c \]
    7. Applied rewrites59.9%

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

    if -2.4e5 < x

    1. Initial program 31.5%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6431.5

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6432.5

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6432.5

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6491.9

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites91.9%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
    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. lower-*.f6490.7

        \[\leadsto \mathsf{log1p}\left(\color{blue}{x \cdot y}\right) \cdot c \]
    7. Applied rewrites90.7%

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

Alternative 8: 76.4% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.6 \cdot 10^{-49}:\\ \;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot y, 0.3333333333333333, \mathsf{fma}\left(-0.5, x, -0.5\right)\right), y, \mathsf{fma}\left(0.16666666666666666, x, 0.5\right)\right), x, 1\right) \cdot c\right) \cdot x\right) \cdot y\\ \end{array} \end{array} \]
(FPCore (c x y)
 :precision binary64
 (if (<= x -1.6e-49)
   (* (* (expm1 x) y) c)
   (*
    (*
     (*
      (fma
       (fma
        (fma (* x y) 0.3333333333333333 (fma -0.5 x -0.5))
        y
        (fma 0.16666666666666666 x 0.5))
       x
       1.0)
      c)
     x)
    y)))
double code(double c, double x, double y) {
	double tmp;
	if (x <= -1.6e-49) {
		tmp = (expm1(x) * y) * c;
	} else {
		tmp = ((fma(fma(fma((x * y), 0.3333333333333333, fma(-0.5, x, -0.5)), y, fma(0.16666666666666666, x, 0.5)), x, 1.0) * c) * x) * y;
	}
	return tmp;
}
function code(c, x, y)
	tmp = 0.0
	if (x <= -1.6e-49)
		tmp = Float64(Float64(expm1(x) * y) * c);
	else
		tmp = Float64(Float64(Float64(fma(fma(fma(Float64(x * y), 0.3333333333333333, fma(-0.5, x, -0.5)), y, fma(0.16666666666666666, x, 0.5)), x, 1.0) * c) * x) * y);
	end
	return tmp
end
code[c_, x_, y_] := If[LessEqual[x, -1.6e-49], N[(N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision] * c), $MachinePrecision], N[(N[(N[(N[(N[(N[(N[(x * y), $MachinePrecision] * 0.3333333333333333 + N[(-0.5 * x + -0.5), $MachinePrecision]), $MachinePrecision] * y + N[(0.16666666666666666 * x + 0.5), $MachinePrecision]), $MachinePrecision] * x + 1.0), $MachinePrecision] * c), $MachinePrecision] * x), $MachinePrecision] * y), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.6 \cdot 10^{-49}:\\
\;\;\;\;\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot c\\

\mathbf{else}:\\
\;\;\;\;\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot y, 0.3333333333333333, \mathsf{fma}\left(-0.5, x, -0.5\right)\right), y, \mathsf{fma}\left(0.16666666666666666, x, 0.5\right)\right), x, 1\right) \cdot c\right) \cdot x\right) \cdot y\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -1.60000000000000001e-49

    1. Initial program 47.1%

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

        \[\leadsto \color{blue}{\log \left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6447.1

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

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

        \[\leadsto \log \color{blue}{\left(1 + \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      6. lower-log1p.f6489.6

        \[\leadsto \color{blue}{\mathsf{log1p}\left(\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y\right)} \cdot c \]
      7. lift-*.f64N/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot y}\right) \cdot c \]
      8. *-commutativeN/A

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      9. lower-*.f6489.6

        \[\leadsto \mathsf{log1p}\left(\color{blue}{y \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      10. lift--.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\left({\mathsf{E}\left(\right)}^{x} - 1\right)}\right) \cdot c \]
      11. lift-pow.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{{\mathsf{E}\left(\right)}^{x}} - 1\right)\right) \cdot c \]
      12. pow-to-expN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(\color{blue}{e^{\log \mathsf{E}\left(\right) \cdot x}} - 1\right)\right) \cdot c \]
      13. lift-E.f64N/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\log \color{blue}{\mathsf{E}\left(\right)} \cdot x} - 1\right)\right) \cdot c \]
      14. log-EN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{1} \cdot x} - 1\right)\right) \cdot c \]
      15. *-lft-identityN/A

        \[\leadsto \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \cdot c \]
      16. lower-expm1.f6499.8

        \[\leadsto \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \cdot c \]
    4. Applied rewrites99.8%

      \[\leadsto \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \cdot c} \]
    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. *-commutativeN/A

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

        \[\leadsto \color{blue}{\left(\left(e^{x} - 1\right) \cdot y\right)} \cdot c \]
      3. lower-expm1.f6458.6

        \[\leadsto \left(\color{blue}{\mathsf{expm1}\left(x\right)} \cdot y\right) \cdot c \]
    7. Applied rewrites58.6%

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

    if -1.60000000000000001e-49 < x

    1. Initial program 31.0%

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

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

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

        \[\leadsto \color{blue}{\left(c \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right) + y \cdot \left(\frac{-1}{2} \cdot \left(c \cdot {\left({\mathsf{E}\left(\right)}^{x} - 1\right)}^{2}\right) + \frac{1}{3} \cdot \left(c \cdot \left(y \cdot {\left({\mathsf{E}\left(\right)}^{x} - 1\right)}^{3}\right)\right)\right)\right) \cdot y} \]
    5. Applied rewrites31.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(c \cdot \left({\left({\mathsf{E}\left(\right)}^{x} - 1\right)}^{2} \cdot \mathsf{fma}\left(0.3333333333333333 \cdot y, {\mathsf{E}\left(\right)}^{x} - 1, -0.5\right)\right), y, \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot c\right) \cdot y} \]
    6. Taylor expanded in x around 0

      \[\leadsto \left(x \cdot \left(c \cdot \log \mathsf{E}\left(\right) + x \cdot \left(\frac{-1}{2} \cdot \left(c \cdot \left(y \cdot {\log \mathsf{E}\left(\right)}^{2}\right)\right) + \left(\frac{1}{2} \cdot \left(c \cdot {\log \mathsf{E}\left(\right)}^{2}\right) + x \cdot \left(\frac{1}{6} \cdot \left(c \cdot {\log \mathsf{E}\left(\right)}^{3}\right) + c \cdot \left(y \cdot \left(\frac{-1}{2} \cdot {\log \mathsf{E}\left(\right)}^{3} + \frac{1}{3} \cdot \left(y \cdot {\log \mathsf{E}\left(\right)}^{3}\right)\right)\right)\right)\right)\right)\right)\right) \cdot y \]
    7. Applied rewrites69.5%

      \[\leadsto \left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.3333333333333333, y, -0.5\right) \cdot y, c, 0.16666666666666666 \cdot c\right), x, \mathsf{fma}\left(-0.5, y \cdot c, 0.5 \cdot c\right)\right), x, c\right) \cdot x\right) \cdot y \]
    8. Taylor expanded in c around 0

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

        \[\leadsto \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.3333333333333333, y, -0.5\right), y, 0.16666666666666666\right), x, \mathsf{fma}\left(-0.5, y, 0.5\right)\right), x, 1\right) \cdot c\right) \cdot x\right) \cdot y \]
      2. Taylor expanded in y around 0

        \[\leadsto \left(\left(\mathsf{fma}\left(\frac{1}{2} + \left(\frac{1}{6} \cdot x + y \cdot \left(\left(\frac{-1}{2} \cdot x + \frac{1}{3} \cdot \left(x \cdot y\right)\right) - \frac{1}{2}\right)\right), x, 1\right) \cdot c\right) \cdot x\right) \cdot y \]
      3. Step-by-step derivation
        1. Applied rewrites82.6%

          \[\leadsto \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot y, 0.3333333333333333, \mathsf{fma}\left(-0.5, x, -0.5\right)\right), y, \mathsf{fma}\left(0.16666666666666666, x, 0.5\right)\right), x, 1\right) \cdot c\right) \cdot x\right) \cdot y \]
      4. Recombined 2 regimes into one program.
      5. Add Preprocessing

      Alternative 9: 63.2% accurate, 3.8× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;c \leq 6 \cdot 10^{-70}:\\ \;\;\;\;\left(c \cdot y\right) \cdot x\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot y, 0.3333333333333333, \mathsf{fma}\left(-0.5, x, -0.5\right)\right), y, \mathsf{fma}\left(0.16666666666666666, x, 0.5\right)\right), x, 1\right) \cdot c\right) \cdot x\right) \cdot y\\ \end{array} \end{array} \]
      (FPCore (c x y)
       :precision binary64
       (if (<= c 6e-70)
         (* (* c y) x)
         (*
          (*
           (*
            (fma
             (fma
              (fma (* x y) 0.3333333333333333 (fma -0.5 x -0.5))
              y
              (fma 0.16666666666666666 x 0.5))
             x
             1.0)
            c)
           x)
          y)))
      double code(double c, double x, double y) {
      	double tmp;
      	if (c <= 6e-70) {
      		tmp = (c * y) * x;
      	} else {
      		tmp = ((fma(fma(fma((x * y), 0.3333333333333333, fma(-0.5, x, -0.5)), y, fma(0.16666666666666666, x, 0.5)), x, 1.0) * c) * x) * y;
      	}
      	return tmp;
      }
      
      function code(c, x, y)
      	tmp = 0.0
      	if (c <= 6e-70)
      		tmp = Float64(Float64(c * y) * x);
      	else
      		tmp = Float64(Float64(Float64(fma(fma(fma(Float64(x * y), 0.3333333333333333, fma(-0.5, x, -0.5)), y, fma(0.16666666666666666, x, 0.5)), x, 1.0) * c) * x) * y);
      	end
      	return tmp
      end
      
      code[c_, x_, y_] := If[LessEqual[c, 6e-70], N[(N[(c * y), $MachinePrecision] * x), $MachinePrecision], N[(N[(N[(N[(N[(N[(N[(x * y), $MachinePrecision] * 0.3333333333333333 + N[(-0.5 * x + -0.5), $MachinePrecision]), $MachinePrecision] * y + N[(0.16666666666666666 * x + 0.5), $MachinePrecision]), $MachinePrecision] * x + 1.0), $MachinePrecision] * c), $MachinePrecision] * x), $MachinePrecision] * y), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;c \leq 6 \cdot 10^{-70}:\\
      \;\;\;\;\left(c \cdot y\right) \cdot x\\
      
      \mathbf{else}:\\
      \;\;\;\;\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot y, 0.3333333333333333, \mathsf{fma}\left(-0.5, x, -0.5\right)\right), y, \mathsf{fma}\left(0.16666666666666666, x, 0.5\right)\right), x, 1\right) \cdot c\right) \cdot x\right) \cdot y\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if c < 6.0000000000000003e-70

        1. Initial program 43.2%

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

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

            \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \color{blue}{1}\right) \]
          3. *-rgt-identityN/A

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

            \[\leadsto \color{blue}{y \cdot \left(c \cdot x\right)} \]
          5. associate-*l*N/A

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

            \[\leadsto \color{blue}{\left(c \cdot y\right)} \cdot x \]
          7. *-lft-identityN/A

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

            \[\leadsto \left(c \cdot \color{blue}{\left(y \cdot 1\right)}\right) \cdot x \]
          9. metadata-evalN/A

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

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

            \[\leadsto \left(c \cdot \left(y \cdot {\color{blue}{1}}^{2}\right)\right) \cdot x \]
          12. metadata-evalN/A

            \[\leadsto \left(c \cdot \left(y \cdot \color{blue}{1}\right)\right) \cdot x \]
          13. log-EN/A

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

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

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

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

            \[\leadsto \left(\color{blue}{\left(1 \cdot y\right)} \cdot c\right) \cdot x \]
          18. *-lft-identityN/A

            \[\leadsto \left(\color{blue}{y} \cdot c\right) \cdot x \]
          19. lower-*.f6461.3

            \[\leadsto \color{blue}{\left(y \cdot c\right)} \cdot x \]
        5. Applied rewrites61.3%

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

        if 6.0000000000000003e-70 < c

        1. Initial program 20.5%

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

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

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

            \[\leadsto \color{blue}{\left(c \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right) + y \cdot \left(\frac{-1}{2} \cdot \left(c \cdot {\left({\mathsf{E}\left(\right)}^{x} - 1\right)}^{2}\right) + \frac{1}{3} \cdot \left(c \cdot \left(y \cdot {\left({\mathsf{E}\left(\right)}^{x} - 1\right)}^{3}\right)\right)\right)\right) \cdot y} \]
        5. Applied rewrites28.0%

          \[\leadsto \color{blue}{\mathsf{fma}\left(c \cdot \left({\left({\mathsf{E}\left(\right)}^{x} - 1\right)}^{2} \cdot \mathsf{fma}\left(0.3333333333333333 \cdot y, {\mathsf{E}\left(\right)}^{x} - 1, -0.5\right)\right), y, \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot c\right) \cdot y} \]
        6. Taylor expanded in x around 0

          \[\leadsto \left(x \cdot \left(c \cdot \log \mathsf{E}\left(\right) + x \cdot \left(\frac{-1}{2} \cdot \left(c \cdot \left(y \cdot {\log \mathsf{E}\left(\right)}^{2}\right)\right) + \left(\frac{1}{2} \cdot \left(c \cdot {\log \mathsf{E}\left(\right)}^{2}\right) + x \cdot \left(\frac{1}{6} \cdot \left(c \cdot {\log \mathsf{E}\left(\right)}^{3}\right) + c \cdot \left(y \cdot \left(\frac{-1}{2} \cdot {\log \mathsf{E}\left(\right)}^{3} + \frac{1}{3} \cdot \left(y \cdot {\log \mathsf{E}\left(\right)}^{3}\right)\right)\right)\right)\right)\right)\right)\right) \cdot y \]
        7. Applied rewrites44.6%

          \[\leadsto \left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.3333333333333333, y, -0.5\right) \cdot y, c, 0.16666666666666666 \cdot c\right), x, \mathsf{fma}\left(-0.5, y \cdot c, 0.5 \cdot c\right)\right), x, c\right) \cdot x\right) \cdot y \]
        8. Taylor expanded in c around 0

          \[\leadsto \left(\left(c \cdot \left(1 + x \cdot \left(\frac{1}{2} + \left(\frac{-1}{2} \cdot y + x \cdot \left(\frac{1}{6} + y \cdot \left(\frac{1}{3} \cdot y - \frac{1}{2}\right)\right)\right)\right)\right)\right) \cdot x\right) \cdot y \]
        9. Step-by-step derivation
          1. Applied rewrites55.0%

            \[\leadsto \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.3333333333333333, y, -0.5\right), y, 0.16666666666666666\right), x, \mathsf{fma}\left(-0.5, y, 0.5\right)\right), x, 1\right) \cdot c\right) \cdot x\right) \cdot y \]
          2. Taylor expanded in y around 0

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

              \[\leadsto \left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot y, 0.3333333333333333, \mathsf{fma}\left(-0.5, x, -0.5\right)\right), y, \mathsf{fma}\left(0.16666666666666666, x, 0.5\right)\right), x, 1\right) \cdot c\right) \cdot x\right) \cdot y \]
          4. Recombined 2 regimes into one program.
          5. Final simplification61.5%

            \[\leadsto \begin{array}{l} \mathbf{if}\;c \leq 6 \cdot 10^{-70}:\\ \;\;\;\;\left(c \cdot y\right) \cdot x\\ \mathbf{else}:\\ \;\;\;\;\left(\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot y, 0.3333333333333333, \mathsf{fma}\left(-0.5, x, -0.5\right)\right), y, \mathsf{fma}\left(0.16666666666666666, x, 0.5\right)\right), x, 1\right) \cdot c\right) \cdot x\right) \cdot y\\ \end{array} \]
          6. Add Preprocessing

          Alternative 10: 63.2% accurate, 5.6× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;c \leq 2.6 \cdot 10^{+135}:\\ \;\;\;\;\left(c \cdot y\right) \cdot x\\ \mathbf{else}:\\ \;\;\;\;\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, c \cdot x, 0.5 \cdot c\right), x, c\right) \cdot x\right) \cdot y\\ \end{array} \end{array} \]
          (FPCore (c x y)
           :precision binary64
           (if (<= c 2.6e+135)
             (* (* c y) x)
             (* (* (fma (fma 0.16666666666666666 (* c x) (* 0.5 c)) x c) x) y)))
          double code(double c, double x, double y) {
          	double tmp;
          	if (c <= 2.6e+135) {
          		tmp = (c * y) * x;
          	} else {
          		tmp = (fma(fma(0.16666666666666666, (c * x), (0.5 * c)), x, c) * x) * y;
          	}
          	return tmp;
          }
          
          function code(c, x, y)
          	tmp = 0.0
          	if (c <= 2.6e+135)
          		tmp = Float64(Float64(c * y) * x);
          	else
          		tmp = Float64(Float64(fma(fma(0.16666666666666666, Float64(c * x), Float64(0.5 * c)), x, c) * x) * y);
          	end
          	return tmp
          end
          
          code[c_, x_, y_] := If[LessEqual[c, 2.6e+135], N[(N[(c * y), $MachinePrecision] * x), $MachinePrecision], N[(N[(N[(N[(0.16666666666666666 * N[(c * x), $MachinePrecision] + N[(0.5 * c), $MachinePrecision]), $MachinePrecision] * x + c), $MachinePrecision] * x), $MachinePrecision] * y), $MachinePrecision]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;c \leq 2.6 \cdot 10^{+135}:\\
          \;\;\;\;\left(c \cdot y\right) \cdot x\\
          
          \mathbf{else}:\\
          \;\;\;\;\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, c \cdot x, 0.5 \cdot c\right), x, c\right) \cdot x\right) \cdot y\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if c < 2.6e135

            1. Initial program 39.5%

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

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

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

                \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \color{blue}{1}\right) \]
              3. *-rgt-identityN/A

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

                \[\leadsto \color{blue}{y \cdot \left(c \cdot x\right)} \]
              5. associate-*l*N/A

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

                \[\leadsto \color{blue}{\left(c \cdot y\right)} \cdot x \]
              7. *-lft-identityN/A

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

                \[\leadsto \left(c \cdot \color{blue}{\left(y \cdot 1\right)}\right) \cdot x \]
              9. metadata-evalN/A

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

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

                \[\leadsto \left(c \cdot \left(y \cdot {\color{blue}{1}}^{2}\right)\right) \cdot x \]
              12. metadata-evalN/A

                \[\leadsto \left(c \cdot \left(y \cdot \color{blue}{1}\right)\right) \cdot x \]
              13. log-EN/A

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

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

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

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

                \[\leadsto \left(\color{blue}{\left(1 \cdot y\right)} \cdot c\right) \cdot x \]
              18. *-lft-identityN/A

                \[\leadsto \left(\color{blue}{y} \cdot c\right) \cdot x \]
              19. lower-*.f6460.5

                \[\leadsto \color{blue}{\left(y \cdot c\right)} \cdot x \]
            5. Applied rewrites60.5%

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

            if 2.6e135 < c

            1. Initial program 17.5%

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

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

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

                \[\leadsto \color{blue}{\left(c \cdot \left({\mathsf{E}\left(\right)}^{x} - 1\right) + y \cdot \left(\frac{-1}{2} \cdot \left(c \cdot {\left({\mathsf{E}\left(\right)}^{x} - 1\right)}^{2}\right) + \frac{1}{3} \cdot \left(c \cdot \left(y \cdot {\left({\mathsf{E}\left(\right)}^{x} - 1\right)}^{3}\right)\right)\right)\right) \cdot y} \]
            5. Applied rewrites17.0%

              \[\leadsto \color{blue}{\mathsf{fma}\left(c \cdot \left({\left({\mathsf{E}\left(\right)}^{x} - 1\right)}^{2} \cdot \mathsf{fma}\left(0.3333333333333333 \cdot y, {\mathsf{E}\left(\right)}^{x} - 1, -0.5\right)\right), y, \left({\mathsf{E}\left(\right)}^{x} - 1\right) \cdot c\right) \cdot y} \]
            6. Taylor expanded in x around 0

              \[\leadsto \left(x \cdot \left(c \cdot \log \mathsf{E}\left(\right) + x \cdot \left(\frac{-1}{2} \cdot \left(c \cdot \left(y \cdot {\log \mathsf{E}\left(\right)}^{2}\right)\right) + \left(\frac{1}{2} \cdot \left(c \cdot {\log \mathsf{E}\left(\right)}^{2}\right) + x \cdot \left(\frac{1}{6} \cdot \left(c \cdot {\log \mathsf{E}\left(\right)}^{3}\right) + c \cdot \left(y \cdot \left(\frac{-1}{2} \cdot {\log \mathsf{E}\left(\right)}^{3} + \frac{1}{3} \cdot \left(y \cdot {\log \mathsf{E}\left(\right)}^{3}\right)\right)\right)\right)\right)\right)\right)\right) \cdot y \]
            7. Applied rewrites37.4%

              \[\leadsto \left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.3333333333333333, y, -0.5\right) \cdot y, c, 0.16666666666666666 \cdot c\right), x, \mathsf{fma}\left(-0.5, y \cdot c, 0.5 \cdot c\right)\right), x, c\right) \cdot x\right) \cdot y \]
            8. Taylor expanded in y around 0

              \[\leadsto \left(\mathsf{fma}\left(\frac{1}{6} \cdot \left(c \cdot x\right) + \frac{1}{2} \cdot c, x, c\right) \cdot x\right) \cdot y \]
            9. Step-by-step derivation
              1. Applied rewrites64.5%

                \[\leadsto \left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, x \cdot c, 0.5 \cdot c\right), x, c\right) \cdot x\right) \cdot y \]
            10. Recombined 2 regimes into one program.
            11. Final simplification61.1%

              \[\leadsto \begin{array}{l} \mathbf{if}\;c \leq 2.6 \cdot 10^{+135}:\\ \;\;\;\;\left(c \cdot y\right) \cdot x\\ \mathbf{else}:\\ \;\;\;\;\left(\mathsf{fma}\left(\mathsf{fma}\left(0.16666666666666666, c \cdot x, 0.5 \cdot c\right), x, c\right) \cdot x\right) \cdot y\\ \end{array} \]
            12. Add Preprocessing

            Alternative 11: 63.3% accurate, 12.8× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;c \leq 0.0001:\\ \;\;\;\;\left(c \cdot y\right) \cdot x\\ \mathbf{else}:\\ \;\;\;\;\left(c \cdot x\right) \cdot y\\ \end{array} \end{array} \]
            (FPCore (c x y)
             :precision binary64
             (if (<= c 0.0001) (* (* c y) x) (* (* c x) y)))
            double code(double c, double x, double y) {
            	double tmp;
            	if (c <= 0.0001) {
            		tmp = (c * y) * x;
            	} else {
            		tmp = (c * x) * y;
            	}
            	return tmp;
            }
            
            real(8) function code(c, x, y)
                real(8), intent (in) :: c
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                real(8) :: tmp
                if (c <= 0.0001d0) 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 <= 0.0001) {
            		tmp = (c * y) * x;
            	} else {
            		tmp = (c * x) * y;
            	}
            	return tmp;
            }
            
            def code(c, x, y):
            	tmp = 0
            	if c <= 0.0001:
            		tmp = (c * y) * x
            	else:
            		tmp = (c * x) * y
            	return tmp
            
            function code(c, x, y)
            	tmp = 0.0
            	if (c <= 0.0001)
            		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 <= 0.0001)
            		tmp = (c * y) * x;
            	else
            		tmp = (c * x) * y;
            	end
            	tmp_2 = tmp;
            end
            
            code[c_, x_, y_] := If[LessEqual[c, 0.0001], N[(N[(c * y), $MachinePrecision] * x), $MachinePrecision], N[(N[(c * x), $MachinePrecision] * y), $MachinePrecision]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;c \leq 0.0001:\\
            \;\;\;\;\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 < 1.00000000000000005e-4

              1. Initial program 43.0%

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

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

                  \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \color{blue}{1}\right) \]
                3. *-rgt-identityN/A

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

                  \[\leadsto \color{blue}{y \cdot \left(c \cdot x\right)} \]
                5. associate-*l*N/A

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

                  \[\leadsto \color{blue}{\left(c \cdot y\right)} \cdot x \]
                7. *-lft-identityN/A

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

                  \[\leadsto \left(c \cdot \color{blue}{\left(y \cdot 1\right)}\right) \cdot x \]
                9. metadata-evalN/A

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

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

                  \[\leadsto \left(c \cdot \left(y \cdot {\color{blue}{1}}^{2}\right)\right) \cdot x \]
                12. metadata-evalN/A

                  \[\leadsto \left(c \cdot \left(y \cdot \color{blue}{1}\right)\right) \cdot x \]
                13. log-EN/A

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

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

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

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

                  \[\leadsto \left(\color{blue}{\left(1 \cdot y\right)} \cdot c\right) \cdot x \]
                18. *-lft-identityN/A

                  \[\leadsto \left(\color{blue}{y} \cdot c\right) \cdot x \]
                19. lower-*.f6460.8

                  \[\leadsto \color{blue}{\left(y \cdot c\right)} \cdot x \]
              5. Applied rewrites60.8%

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

              if 1.00000000000000005e-4 < c

              1. Initial program 17.4%

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

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

                  \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \color{blue}{1}\right) \]
                3. *-rgt-identityN/A

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

                  \[\leadsto \color{blue}{y \cdot \left(c \cdot x\right)} \]
                5. associate-*l*N/A

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

                  \[\leadsto \color{blue}{\left(c \cdot y\right)} \cdot x \]
                7. *-lft-identityN/A

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

                  \[\leadsto \left(c \cdot \color{blue}{\left(y \cdot 1\right)}\right) \cdot x \]
                9. metadata-evalN/A

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

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

                  \[\leadsto \left(c \cdot \left(y \cdot {\color{blue}{1}}^{2}\right)\right) \cdot x \]
                12. metadata-evalN/A

                  \[\leadsto \left(c \cdot \left(y \cdot \color{blue}{1}\right)\right) \cdot x \]
                13. log-EN/A

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

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

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

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

                  \[\leadsto \left(\color{blue}{\left(1 \cdot y\right)} \cdot c\right) \cdot x \]
                18. *-lft-identityN/A

                  \[\leadsto \left(\color{blue}{y} \cdot c\right) \cdot x \]
                19. lower-*.f6451.5

                  \[\leadsto \color{blue}{\left(y \cdot c\right)} \cdot x \]
              5. Applied rewrites51.5%

                \[\leadsto \color{blue}{\left(y \cdot c\right) \cdot x} \]
              6. Step-by-step derivation
                1. Applied rewrites61.8%

                  \[\leadsto \left(c \cdot x\right) \cdot \color{blue}{y} \]
              7. Recombined 2 regimes into one program.
              8. Final simplification61.0%

                \[\leadsto \begin{array}{l} \mathbf{if}\;c \leq 0.0001:\\ \;\;\;\;\left(c \cdot y\right) \cdot x\\ \mathbf{else}:\\ \;\;\;\;\left(c \cdot x\right) \cdot y\\ \end{array} \]
              9. Add Preprocessing

              Alternative 12: 58.9% 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;
              }
              
              real(8) function code(c, x, y)
                  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 36.2%

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

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

                  \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \color{blue}{1}\right) \]
                3. *-rgt-identityN/A

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

                  \[\leadsto \color{blue}{y \cdot \left(c \cdot x\right)} \]
                5. associate-*l*N/A

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

                  \[\leadsto \color{blue}{\left(c \cdot y\right)} \cdot x \]
                7. *-lft-identityN/A

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

                  \[\leadsto \left(c \cdot \color{blue}{\left(y \cdot 1\right)}\right) \cdot x \]
                9. metadata-evalN/A

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

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

                  \[\leadsto \left(c \cdot \left(y \cdot {\color{blue}{1}}^{2}\right)\right) \cdot x \]
                12. metadata-evalN/A

                  \[\leadsto \left(c \cdot \left(y \cdot \color{blue}{1}\right)\right) \cdot x \]
                13. log-EN/A

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

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

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

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

                  \[\leadsto \left(\color{blue}{\left(1 \cdot y\right)} \cdot c\right) \cdot x \]
                18. *-lft-identityN/A

                  \[\leadsto \left(\color{blue}{y} \cdot c\right) \cdot x \]
                19. lower-*.f6458.3

                  \[\leadsto \color{blue}{\left(y \cdot c\right)} \cdot x \]
              5. Applied rewrites58.3%

                \[\leadsto \color{blue}{\left(y \cdot c\right) \cdot x} \]
              6. Step-by-step derivation
                1. Applied rewrites59.2%

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

                Developer Target 1: 93.3% 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 2024277 
                (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)))))