Logarithmic Transform

Percentage Accurate: 41.2% → 98.7%
Time: 5.9s
Alternatives: 8
Speedup: 5.0×

Specification

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

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 8 alternatives:

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

Initial Program: 41.2% accurate, 1.0× speedup?

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

Alternative 1: 98.7% accurate, 0.7× speedup?

\[\begin{array}{l} t_0 := c \cdot \mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right)\\ \mathbf{if}\;y \leq -5 \cdot 10^{-23}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y \leq 3.8 \cdot 10^{-133}:\\ \;\;\;\;\left(c \cdot \mathsf{fma}\left(\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot \mathsf{expm1}\left(x\right), -0.5, \mathsf{expm1}\left(x\right)\right)\right) \cdot y\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \]
(FPCore (c x y)
  :precision binary64
  (let* ((t_0 (* c (log1p (* y (expm1 x))))))
  (if (<= y -5e-23)
    t_0
    (if (<= y 3.8e-133)
      (* (* c (fma (* (* (expm1 x) y) (expm1 x)) -0.5 (expm1 x))) y)
      t_0))))
double code(double c, double x, double y) {
	double t_0 = c * log1p((y * expm1(x)));
	double tmp;
	if (y <= -5e-23) {
		tmp = t_0;
	} else if (y <= 3.8e-133) {
		tmp = (c * fma(((expm1(x) * y) * expm1(x)), -0.5, expm1(x))) * y;
	} else {
		tmp = t_0;
	}
	return tmp;
}
function code(c, x, y)
	t_0 = Float64(c * log1p(Float64(y * expm1(x))))
	tmp = 0.0
	if (y <= -5e-23)
		tmp = t_0;
	elseif (y <= 3.8e-133)
		tmp = Float64(Float64(c * fma(Float64(Float64(expm1(x) * y) * expm1(x)), -0.5, expm1(x))) * y);
	else
		tmp = t_0;
	end
	return tmp
end
code[c_, x_, y_] := Block[{t$95$0 = N[(c * N[Log[1 + N[(y * N[(Exp[x] - 1), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -5e-23], t$95$0, If[LessEqual[y, 3.8e-133], N[(N[(c * N[(N[(N[(N[(Exp[x] - 1), $MachinePrecision] * y), $MachinePrecision] * N[(Exp[x] - 1), $MachinePrecision]), $MachinePrecision] * -0.5 + N[(Exp[x] - 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * y), $MachinePrecision], t$95$0]]]
\begin{array}{l}
t_0 := c \cdot \mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right)\\
\mathbf{if}\;y \leq -5 \cdot 10^{-23}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;y \leq 3.8 \cdot 10^{-133}:\\
\;\;\;\;\left(c \cdot \mathsf{fma}\left(\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot \mathsf{expm1}\left(x\right), -0.5, \mathsf{expm1}\left(x\right)\right)\right) \cdot y\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -5.0000000000000002e-23 or 3.8000000000000003e-133 < y

    1. Initial program 41.2%

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

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

        \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
      3. lower-log1p.f6456.1%

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(\color{blue}{y \cdot \left({e}^{x} - 1\right)}\right) \]
      6. lower-*.f6456.1%

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

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

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

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

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \]
      13. lower-expm1.f6493.4%

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \]
    3. Applied rewrites93.4%

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

    if -5.0000000000000002e-23 < y < 3.8000000000000003e-133

    1. Initial program 41.2%

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

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

        \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
      3. lower-log1p.f6456.1%

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(\color{blue}{y \cdot \left({e}^{x} - 1\right)}\right) \]
      6. lower-*.f6456.1%

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

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

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

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

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \]
      13. lower-expm1.f6493.4%

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \]
    3. Applied rewrites93.4%

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

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

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

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

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

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

        \[\leadsto y \cdot \mathsf{fma}\left(\frac{-1}{2}, c \cdot \left(y \cdot {\left(e^{x} - 1\right)}^{\color{blue}{2}}\right), c \cdot \left(e^{x} - 1\right)\right) \]
      6. lower-expm1.f64N/A

        \[\leadsto y \cdot \mathsf{fma}\left(\frac{-1}{2}, c \cdot \left(y \cdot {\left(\mathsf{expm1}\left(x\right)\right)}^{2}\right), c \cdot \left(e^{x} - 1\right)\right) \]
      7. lower-*.f64N/A

        \[\leadsto y \cdot \mathsf{fma}\left(\frac{-1}{2}, c \cdot \left(y \cdot {\left(\mathsf{expm1}\left(x\right)\right)}^{2}\right), c \cdot \left(e^{x} - 1\right)\right) \]
      8. lower-expm1.f6476.1%

        \[\leadsto y \cdot \mathsf{fma}\left(-0.5, c \cdot \left(y \cdot {\left(\mathsf{expm1}\left(x\right)\right)}^{2}\right), c \cdot \mathsf{expm1}\left(x\right)\right) \]
    6. Applied rewrites76.1%

      \[\leadsto \color{blue}{y \cdot \mathsf{fma}\left(-0.5, c \cdot \left(y \cdot {\left(\mathsf{expm1}\left(x\right)\right)}^{2}\right), c \cdot \mathsf{expm1}\left(x\right)\right)} \]
    7. Step-by-step derivation
      1. lift-*.f64N/A

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

        \[\leadsto \mathsf{fma}\left(\frac{-1}{2}, c \cdot \left(y \cdot {\left(\mathsf{expm1}\left(x\right)\right)}^{2}\right), c \cdot \mathsf{expm1}\left(x\right)\right) \cdot \color{blue}{y} \]
      3. lower-*.f6476.1%

        \[\leadsto \mathsf{fma}\left(-0.5, c \cdot \left(y \cdot {\left(\mathsf{expm1}\left(x\right)\right)}^{2}\right), c \cdot \mathsf{expm1}\left(x\right)\right) \cdot \color{blue}{y} \]
    8. Applied rewrites76.1%

      \[\leadsto \left(c \cdot \mathsf{fma}\left(\left(\mathsf{expm1}\left(x\right) \cdot y\right) \cdot \mathsf{expm1}\left(x\right), -0.5, \mathsf{expm1}\left(x\right)\right)\right) \cdot \color{blue}{y} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 2: 93.4% accurate, 1.4× speedup?

\[c \cdot \mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right) \]
(FPCore (c x y)
  :precision binary64
  (* c (log1p (* y (expm1 x)))))
double code(double c, double x, double y) {
	return c * log1p((y * expm1(x)));
}
public static double code(double c, double x, double y) {
	return c * Math.log1p((y * Math.expm1(x)));
}
def code(c, x, y):
	return c * math.log1p((y * math.expm1(x)))
function code(c, x, y)
	return Float64(c * log1p(Float64(y * expm1(x))))
end
code[c_, x_, y_] := N[(c * N[Log[1 + N[(y * N[(Exp[x] - 1), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
c \cdot \mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(x\right)\right)
Derivation
  1. Initial program 41.2%

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

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

      \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
    3. lower-log1p.f6456.1%

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

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

      \[\leadsto c \cdot \mathsf{log1p}\left(\color{blue}{y \cdot \left({e}^{x} - 1\right)}\right) \]
    6. lower-*.f6456.1%

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

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

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

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

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

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

      \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \]
    13. lower-expm1.f6493.4%

      \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \]
  3. Applied rewrites93.4%

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

Alternative 3: 92.2% accurate, 0.3× speedup?

\[\begin{array}{l} t_0 := \left({e}^{x} - 1\right) \cdot y\\ t_1 := c \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right)\\ \mathbf{if}\;t\_0 \leq -1 \cdot 10^{-278}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;t\_0 \leq 0:\\ \;\;\;\;c \cdot \mathsf{log1p}\left(x \cdot y\right)\\ \mathbf{elif}\;t\_0 \leq 2 \cdot 10^{-18}:\\ \;\;\;\;t\_1\\ \mathbf{else}:\\ \;\;\;\;\log \left(\mathsf{fma}\left(y, \mathsf{expm1}\left(x\right), 1\right)\right) \cdot c\\ \end{array} \]
(FPCore (c x y)
  :precision binary64
  (let* ((t_0 (* (- (pow E x) 1.0) y)) (t_1 (* c (* y (expm1 x)))))
  (if (<= t_0 -1e-278)
    t_1
    (if (<= t_0 0.0)
      (* c (log1p (* x y)))
      (if (<= t_0 2e-18) t_1 (* (log (fma y (expm1 x) 1.0)) c))))))
double code(double c, double x, double y) {
	double t_0 = (pow(((double) M_E), x) - 1.0) * y;
	double t_1 = c * (y * expm1(x));
	double tmp;
	if (t_0 <= -1e-278) {
		tmp = t_1;
	} else if (t_0 <= 0.0) {
		tmp = c * log1p((x * y));
	} else if (t_0 <= 2e-18) {
		tmp = t_1;
	} else {
		tmp = log(fma(y, expm1(x), 1.0)) * c;
	}
	return tmp;
}
function code(c, x, y)
	t_0 = Float64(Float64((exp(1) ^ x) - 1.0) * y)
	t_1 = Float64(c * Float64(y * expm1(x)))
	tmp = 0.0
	if (t_0 <= -1e-278)
		tmp = t_1;
	elseif (t_0 <= 0.0)
		tmp = Float64(c * log1p(Float64(x * y)));
	elseif (t_0 <= 2e-18)
		tmp = t_1;
	else
		tmp = Float64(log(fma(y, expm1(x), 1.0)) * c);
	end
	return tmp
end
code[c_, x_, y_] := Block[{t$95$0 = N[(N[(N[Power[E, x], $MachinePrecision] - 1.0), $MachinePrecision] * y), $MachinePrecision]}, Block[{t$95$1 = N[(c * N[(y * N[(Exp[x] - 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -1e-278], t$95$1, If[LessEqual[t$95$0, 0.0], N[(c * N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 2e-18], t$95$1, N[(N[Log[N[(y * N[(Exp[x] - 1), $MachinePrecision] + 1.0), $MachinePrecision]], $MachinePrecision] * c), $MachinePrecision]]]]]]
\begin{array}{l}
t_0 := \left({e}^{x} - 1\right) \cdot y\\
t_1 := c \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right)\\
\mathbf{if}\;t\_0 \leq -1 \cdot 10^{-278}:\\
\;\;\;\;t\_1\\

\mathbf{elif}\;t\_0 \leq 0:\\
\;\;\;\;c \cdot \mathsf{log1p}\left(x \cdot y\right)\\

\mathbf{elif}\;t\_0 \leq 2 \cdot 10^{-18}:\\
\;\;\;\;t\_1\\

\mathbf{else}:\\
\;\;\;\;\log \left(\mathsf{fma}\left(y, \mathsf{expm1}\left(x\right), 1\right)\right) \cdot c\\


\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (*.f64 (-.f64 (pow.f64 (E.f64) x) #s(literal 1 binary64)) y) < -9.9999999999999994e-279 or 0.0 < (*.f64 (-.f64 (pow.f64 (E.f64) x) #s(literal 1 binary64)) y) < 2.0000000000000001e-18

    1. Initial program 41.2%

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

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

        \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
      3. lower-log1p.f6456.1%

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(\color{blue}{y \cdot \left({e}^{x} - 1\right)}\right) \]
      6. lower-*.f6456.1%

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

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

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

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

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \]
      13. lower-expm1.f6493.4%

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \]
    3. Applied rewrites93.4%

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

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

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

        \[\leadsto c \cdot \left(y \cdot \color{blue}{\left(e^{x} - 1\right)}\right) \]
      3. lower-expm1.f6473.6%

        \[\leadsto c \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right) \]
    6. Applied rewrites73.6%

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

    if -9.9999999999999994e-279 < (*.f64 (-.f64 (pow.f64 (E.f64) x) #s(literal 1 binary64)) y) < 0.0

    1. Initial program 41.2%

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

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

        \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
      3. lower-log1p.f6456.1%

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(\color{blue}{y \cdot \left({e}^{x} - 1\right)}\right) \]
      6. lower-*.f6456.1%

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

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

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

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

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \]
      13. lower-expm1.f6493.4%

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \]
    3. Applied rewrites93.4%

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

      \[\leadsto c \cdot \mathsf{log1p}\left(\color{blue}{x \cdot y}\right) \]
    5. Step-by-step derivation
      1. lower-*.f6466.3%

        \[\leadsto c \cdot \mathsf{log1p}\left(x \cdot \color{blue}{y}\right) \]
    6. Applied rewrites66.3%

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

    if 2.0000000000000001e-18 < (*.f64 (-.f64 (pow.f64 (E.f64) x) #s(literal 1 binary64)) y)

    1. Initial program 41.2%

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

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

        \[\leadsto \color{blue}{\log \left(1 + \left({e}^{x} - 1\right) \cdot y\right) \cdot c} \]
      3. lower-*.f6441.2%

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

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

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

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

        \[\leadsto \log \left(\color{blue}{y \cdot \left({e}^{x} - 1\right)} + 1\right) \cdot c \]
      8. lower-fma.f6441.2%

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

        \[\leadsto \log \left(\mathsf{fma}\left(y, \color{blue}{{e}^{x} - 1}, 1\right)\right) \cdot c \]
      10. lift-pow.f64N/A

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

        \[\leadsto \log \left(\mathsf{fma}\left(y, {\color{blue}{\mathsf{E}\left(\right)}}^{x} - 1, 1\right)\right) \cdot c \]
      12. e-exp-1N/A

        \[\leadsto \log \left(\mathsf{fma}\left(y, {\color{blue}{\left(e^{1}\right)}}^{x} - 1, 1\right)\right) \cdot c \]
      13. pow-expN/A

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

        \[\leadsto \log \left(\mathsf{fma}\left(y, e^{\color{blue}{x}} - 1, 1\right)\right) \cdot c \]
      15. lower-expm1.f6451.3%

        \[\leadsto \log \left(\mathsf{fma}\left(y, \color{blue}{\mathsf{expm1}\left(x\right)}, 1\right)\right) \cdot c \]
    3. Applied rewrites51.3%

      \[\leadsto \color{blue}{\log \left(\mathsf{fma}\left(y, \mathsf{expm1}\left(x\right), 1\right)\right) \cdot c} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 4: 82.7% accurate, 1.7× speedup?

\[\begin{array}{l} \mathbf{if}\;x \leq -3.35 \cdot 10^{-12}:\\ \;\;\;\;c \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right)\\ \mathbf{else}:\\ \;\;\;\;c \cdot \mathsf{log1p}\left(x \cdot y\right)\\ \end{array} \]
(FPCore (c x y)
  :precision binary64
  (if (<= x -3.35e-12) (* c (* y (expm1 x))) (* c (log1p (* x y)))))
double code(double c, double x, double y) {
	double tmp;
	if (x <= -3.35e-12) {
		tmp = c * (y * expm1(x));
	} else {
		tmp = c * log1p((x * y));
	}
	return tmp;
}
public static double code(double c, double x, double y) {
	double tmp;
	if (x <= -3.35e-12) {
		tmp = c * (y * Math.expm1(x));
	} else {
		tmp = c * Math.log1p((x * y));
	}
	return tmp;
}
def code(c, x, y):
	tmp = 0
	if x <= -3.35e-12:
		tmp = c * (y * math.expm1(x))
	else:
		tmp = c * math.log1p((x * y))
	return tmp
function code(c, x, y)
	tmp = 0.0
	if (x <= -3.35e-12)
		tmp = Float64(c * Float64(y * expm1(x)));
	else
		tmp = Float64(c * log1p(Float64(x * y)));
	end
	return tmp
end
code[c_, x_, y_] := If[LessEqual[x, -3.35e-12], N[(c * N[(y * N[(Exp[x] - 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(c * N[Log[1 + N[(x * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\mathbf{if}\;x \leq -3.35 \cdot 10^{-12}:\\
\;\;\;\;c \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right)\\

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


\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -3.3500000000000001e-12

    1. Initial program 41.2%

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

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

        \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
      3. lower-log1p.f6456.1%

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(\color{blue}{y \cdot \left({e}^{x} - 1\right)}\right) \]
      6. lower-*.f6456.1%

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

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

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

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

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \]
      13. lower-expm1.f6493.4%

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \]
    3. Applied rewrites93.4%

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

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

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

        \[\leadsto c \cdot \left(y \cdot \color{blue}{\left(e^{x} - 1\right)}\right) \]
      3. lower-expm1.f6473.6%

        \[\leadsto c \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right) \]
    6. Applied rewrites73.6%

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

    if -3.3500000000000001e-12 < x

    1. Initial program 41.2%

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

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

        \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
      3. lower-log1p.f6456.1%

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(\color{blue}{y \cdot \left({e}^{x} - 1\right)}\right) \]
      6. lower-*.f6456.1%

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

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

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

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

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \]
      13. lower-expm1.f6493.4%

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \]
    3. Applied rewrites93.4%

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

      \[\leadsto c \cdot \mathsf{log1p}\left(\color{blue}{x \cdot y}\right) \]
    5. Step-by-step derivation
      1. lower-*.f6466.3%

        \[\leadsto c \cdot \mathsf{log1p}\left(x \cdot \color{blue}{y}\right) \]
    6. Applied rewrites66.3%

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

Alternative 5: 76.0% accurate, 2.0× speedup?

\[\begin{array}{l} \mathbf{if}\;x \leq -1.45 \cdot 10^{-86}:\\ \;\;\;\;c \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right)\\ \mathbf{elif}\;x \leq 4.38 \cdot 10^{-277}:\\ \;\;\;\;\left(y \cdot c\right) \cdot x\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot c\right) \cdot y\\ \end{array} \]
(FPCore (c x y)
  :precision binary64
  (if (<= x -1.45e-86)
  (* c (* y (expm1 x)))
  (if (<= x 4.38e-277) (* (* y c) x) (* (* x c) y))))
double code(double c, double x, double y) {
	double tmp;
	if (x <= -1.45e-86) {
		tmp = c * (y * expm1(x));
	} else if (x <= 4.38e-277) {
		tmp = (y * c) * x;
	} else {
		tmp = (x * c) * y;
	}
	return tmp;
}
public static double code(double c, double x, double y) {
	double tmp;
	if (x <= -1.45e-86) {
		tmp = c * (y * Math.expm1(x));
	} else if (x <= 4.38e-277) {
		tmp = (y * c) * x;
	} else {
		tmp = (x * c) * y;
	}
	return tmp;
}
def code(c, x, y):
	tmp = 0
	if x <= -1.45e-86:
		tmp = c * (y * math.expm1(x))
	elif x <= 4.38e-277:
		tmp = (y * c) * x
	else:
		tmp = (x * c) * y
	return tmp
function code(c, x, y)
	tmp = 0.0
	if (x <= -1.45e-86)
		tmp = Float64(c * Float64(y * expm1(x)));
	elseif (x <= 4.38e-277)
		tmp = Float64(Float64(y * c) * x);
	else
		tmp = Float64(Float64(x * c) * y);
	end
	return tmp
end
code[c_, x_, y_] := If[LessEqual[x, -1.45e-86], N[(c * N[(y * N[(Exp[x] - 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 4.38e-277], N[(N[(y * c), $MachinePrecision] * x), $MachinePrecision], N[(N[(x * c), $MachinePrecision] * y), $MachinePrecision]]]
\begin{array}{l}
\mathbf{if}\;x \leq -1.45 \cdot 10^{-86}:\\
\;\;\;\;c \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right)\\

\mathbf{elif}\;x \leq 4.38 \cdot 10^{-277}:\\
\;\;\;\;\left(y \cdot c\right) \cdot x\\

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


\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -1.45e-86

    1. Initial program 41.2%

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

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

        \[\leadsto c \cdot \log \color{blue}{\left(1 + \left({e}^{x} - 1\right) \cdot y\right)} \]
      3. lower-log1p.f6456.1%

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(\color{blue}{y \cdot \left({e}^{x} - 1\right)}\right) \]
      6. lower-*.f6456.1%

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

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

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

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

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

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

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \left(e^{\color{blue}{x}} - 1\right)\right) \]
      13. lower-expm1.f6493.4%

        \[\leadsto c \cdot \mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(x\right)}\right) \]
    3. Applied rewrites93.4%

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

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

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

        \[\leadsto c \cdot \left(y \cdot \color{blue}{\left(e^{x} - 1\right)}\right) \]
      3. lower-expm1.f6473.6%

        \[\leadsto c \cdot \left(y \cdot \mathsf{expm1}\left(x\right)\right) \]
    6. Applied rewrites73.6%

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

    if -1.45e-86 < x < 4.3800000000000001e-277

    1. Initial program 41.2%

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

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

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

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

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

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log \mathsf{E}\left(\right)\right)\right) \]
      5. lower-E.f6455.9%

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log e\right)\right) \]
    4. Applied rewrites55.9%

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

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

        \[\leadsto c \cdot \left(x \cdot \color{blue}{\left(y \cdot \log e\right)}\right) \]
      3. associate-*r*N/A

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

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

        \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \log e\right) \]
      6. lift-E.f64N/A

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

        \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot 1\right) \]
      8. *-rgt-identityN/A

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

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

        \[\leadsto \left(x \cdot c\right) \cdot y \]
      11. lower-*.f6459.0%

        \[\leadsto \left(x \cdot c\right) \cdot y \]
    6. Applied rewrites59.0%

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

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

        \[\leadsto \left(x \cdot c\right) \cdot y \]
      3. associate-*l*N/A

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

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

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

        \[\leadsto \left(y \cdot c\right) \cdot x \]
      7. lower-*.f6461.4%

        \[\leadsto \left(y \cdot c\right) \cdot x \]
    8. Applied rewrites61.4%

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

    if 4.3800000000000001e-277 < x

    1. Initial program 41.2%

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

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

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

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

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

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log \mathsf{E}\left(\right)\right)\right) \]
      5. lower-E.f6455.9%

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log e\right)\right) \]
    4. Applied rewrites55.9%

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

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

        \[\leadsto c \cdot \left(x \cdot \color{blue}{\left(y \cdot \log e\right)}\right) \]
      3. associate-*r*N/A

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

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

        \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \log e\right) \]
      6. lift-E.f64N/A

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

        \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot 1\right) \]
      8. *-rgt-identityN/A

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

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

        \[\leadsto \left(x \cdot c\right) \cdot y \]
      11. lower-*.f6459.0%

        \[\leadsto \left(x \cdot c\right) \cdot y \]
    6. Applied rewrites59.0%

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

Alternative 6: 64.4% accurate, 1.9× speedup?

\[\mathsf{copysign}\left(1, c\right) \cdot \begin{array}{l} \mathbf{if}\;\left|c\right| \leq 5.5 \cdot 10^{-41}:\\ \;\;\;\;\left(y \cdot \left|c\right|\right) \cdot x\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot \left|c\right|\right) \cdot y\\ \end{array} \]
(FPCore (c x y)
  :precision binary64
  (*
 (copysign 1.0 c)
 (if (<= (fabs c) 5.5e-41) (* (* y (fabs c)) x) (* (* x (fabs c)) y))))
double code(double c, double x, double y) {
	double tmp;
	if (fabs(c) <= 5.5e-41) {
		tmp = (y * fabs(c)) * x;
	} else {
		tmp = (x * fabs(c)) * y;
	}
	return copysign(1.0, c) * tmp;
}
public static double code(double c, double x, double y) {
	double tmp;
	if (Math.abs(c) <= 5.5e-41) {
		tmp = (y * Math.abs(c)) * x;
	} else {
		tmp = (x * Math.abs(c)) * y;
	}
	return Math.copySign(1.0, c) * tmp;
}
def code(c, x, y):
	tmp = 0
	if math.fabs(c) <= 5.5e-41:
		tmp = (y * math.fabs(c)) * x
	else:
		tmp = (x * math.fabs(c)) * y
	return math.copysign(1.0, c) * tmp
function code(c, x, y)
	tmp = 0.0
	if (abs(c) <= 5.5e-41)
		tmp = Float64(Float64(y * abs(c)) * x);
	else
		tmp = Float64(Float64(x * abs(c)) * y);
	end
	return Float64(copysign(1.0, c) * tmp)
end
function tmp_2 = code(c, x, y)
	tmp = 0.0;
	if (abs(c) <= 5.5e-41)
		tmp = (y * abs(c)) * x;
	else
		tmp = (x * abs(c)) * y;
	end
	tmp_2 = (sign(c) * abs(1.0)) * tmp;
end
code[c_, x_, y_] := N[(N[With[{TMP1 = Abs[1.0], TMP2 = Sign[c]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision] * If[LessEqual[N[Abs[c], $MachinePrecision], 5.5e-41], N[(N[(y * N[Abs[c], $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision], N[(N[(x * N[Abs[c], $MachinePrecision]), $MachinePrecision] * y), $MachinePrecision]]), $MachinePrecision]
\mathsf{copysign}\left(1, c\right) \cdot \begin{array}{l}
\mathbf{if}\;\left|c\right| \leq 5.5 \cdot 10^{-41}:\\
\;\;\;\;\left(y \cdot \left|c\right|\right) \cdot x\\

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


\end{array}
Derivation
  1. Split input into 2 regimes
  2. if c < 5.5000000000000002e-41

    1. Initial program 41.2%

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

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

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

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

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

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log \mathsf{E}\left(\right)\right)\right) \]
      5. lower-E.f6455.9%

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log e\right)\right) \]
    4. Applied rewrites55.9%

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

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

        \[\leadsto c \cdot \left(x \cdot \color{blue}{\left(y \cdot \log e\right)}\right) \]
      3. associate-*r*N/A

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

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

        \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \log e\right) \]
      6. lift-E.f64N/A

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

        \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot 1\right) \]
      8. *-rgt-identityN/A

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

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

        \[\leadsto \left(x \cdot c\right) \cdot y \]
      11. lower-*.f6459.0%

        \[\leadsto \left(x \cdot c\right) \cdot y \]
    6. Applied rewrites59.0%

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

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

        \[\leadsto \left(x \cdot c\right) \cdot y \]
      3. associate-*l*N/A

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

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

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

        \[\leadsto \left(y \cdot c\right) \cdot x \]
      7. lower-*.f6461.4%

        \[\leadsto \left(y \cdot c\right) \cdot x \]
    8. Applied rewrites61.4%

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

    if 5.5000000000000002e-41 < c

    1. Initial program 41.2%

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

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

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

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

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

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log \mathsf{E}\left(\right)\right)\right) \]
      5. lower-E.f6455.9%

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log e\right)\right) \]
    4. Applied rewrites55.9%

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

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

        \[\leadsto c \cdot \left(x \cdot \color{blue}{\left(y \cdot \log e\right)}\right) \]
      3. associate-*r*N/A

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

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

        \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \log e\right) \]
      6. lift-E.f64N/A

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

        \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot 1\right) \]
      8. *-rgt-identityN/A

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

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

        \[\leadsto \left(x \cdot c\right) \cdot y \]
      11. lower-*.f6459.0%

        \[\leadsto \left(x \cdot c\right) \cdot y \]
    6. Applied rewrites59.0%

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

Alternative 7: 61.8% accurate, 1.9× speedup?

\[\mathsf{copysign}\left(1, c\right) \cdot \begin{array}{l} \mathbf{if}\;\left|c\right| \leq 5.5 \cdot 10^{-41}:\\ \;\;\;\;\left(x \cdot y\right) \cdot \left|c\right|\\ \mathbf{else}:\\ \;\;\;\;\left(x \cdot \left|c\right|\right) \cdot y\\ \end{array} \]
(FPCore (c x y)
  :precision binary64
  (*
 (copysign 1.0 c)
 (if (<= (fabs c) 5.5e-41) (* (* x y) (fabs c)) (* (* x (fabs c)) y))))
double code(double c, double x, double y) {
	double tmp;
	if (fabs(c) <= 5.5e-41) {
		tmp = (x * y) * fabs(c);
	} else {
		tmp = (x * fabs(c)) * y;
	}
	return copysign(1.0, c) * tmp;
}
public static double code(double c, double x, double y) {
	double tmp;
	if (Math.abs(c) <= 5.5e-41) {
		tmp = (x * y) * Math.abs(c);
	} else {
		tmp = (x * Math.abs(c)) * y;
	}
	return Math.copySign(1.0, c) * tmp;
}
def code(c, x, y):
	tmp = 0
	if math.fabs(c) <= 5.5e-41:
		tmp = (x * y) * math.fabs(c)
	else:
		tmp = (x * math.fabs(c)) * y
	return math.copysign(1.0, c) * tmp
function code(c, x, y)
	tmp = 0.0
	if (abs(c) <= 5.5e-41)
		tmp = Float64(Float64(x * y) * abs(c));
	else
		tmp = Float64(Float64(x * abs(c)) * y);
	end
	return Float64(copysign(1.0, c) * tmp)
end
function tmp_2 = code(c, x, y)
	tmp = 0.0;
	if (abs(c) <= 5.5e-41)
		tmp = (x * y) * abs(c);
	else
		tmp = (x * abs(c)) * y;
	end
	tmp_2 = (sign(c) * abs(1.0)) * tmp;
end
code[c_, x_, y_] := N[(N[With[{TMP1 = Abs[1.0], TMP2 = Sign[c]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision] * If[LessEqual[N[Abs[c], $MachinePrecision], 5.5e-41], N[(N[(x * y), $MachinePrecision] * N[Abs[c], $MachinePrecision]), $MachinePrecision], N[(N[(x * N[Abs[c], $MachinePrecision]), $MachinePrecision] * y), $MachinePrecision]]), $MachinePrecision]
\mathsf{copysign}\left(1, c\right) \cdot \begin{array}{l}
\mathbf{if}\;\left|c\right| \leq 5.5 \cdot 10^{-41}:\\
\;\;\;\;\left(x \cdot y\right) \cdot \left|c\right|\\

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


\end{array}
Derivation
  1. Split input into 2 regimes
  2. if c < 5.5000000000000002e-41

    1. Initial program 41.2%

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

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

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

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

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

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log \mathsf{E}\left(\right)\right)\right) \]
      5. lower-E.f6455.9%

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log e\right)\right) \]
    4. Applied rewrites55.9%

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

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

        \[\leadsto \left(x \cdot \left(y \cdot \log e\right)\right) \cdot \color{blue}{c} \]
      3. lower-*.f6455.9%

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

        \[\leadsto \left(x \cdot \left(y \cdot \log e\right)\right) \cdot c \]
      5. lift-log.f64N/A

        \[\leadsto \left(x \cdot \left(y \cdot \log e\right)\right) \cdot c \]
      6. lift-E.f64N/A

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

        \[\leadsto \left(x \cdot \left(y \cdot 1\right)\right) \cdot c \]
      8. *-rgt-identity55.9%

        \[\leadsto \left(x \cdot y\right) \cdot c \]
    6. Applied rewrites55.9%

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

    if 5.5000000000000002e-41 < c

    1. Initial program 41.2%

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

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

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

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

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

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log \mathsf{E}\left(\right)\right)\right) \]
      5. lower-E.f6455.9%

        \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log e\right)\right) \]
    4. Applied rewrites55.9%

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

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

        \[\leadsto c \cdot \left(x \cdot \color{blue}{\left(y \cdot \log e\right)}\right) \]
      3. associate-*r*N/A

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

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

        \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \log e\right) \]
      6. lift-E.f64N/A

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

        \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot 1\right) \]
      8. *-rgt-identityN/A

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

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

        \[\leadsto \left(x \cdot c\right) \cdot y \]
      11. lower-*.f6459.0%

        \[\leadsto \left(x \cdot c\right) \cdot y \]
    6. Applied rewrites59.0%

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

Alternative 8: 59.0% accurate, 5.0× speedup?

\[\left(x \cdot c\right) \cdot y \]
(FPCore (c x y)
  :precision binary64
  (* (* x c) y))
double code(double c, double x, double y) {
	return (x * c) * y;
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(c, x, y)
use fmin_fmax_functions
    real(8), intent (in) :: c
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    code = (x * c) * y
end function
public static double code(double c, double x, double y) {
	return (x * c) * y;
}
def code(c, x, y):
	return (x * c) * y
function code(c, x, y)
	return Float64(Float64(x * c) * y)
end
function tmp = code(c, x, y)
	tmp = (x * c) * y;
end
code[c_, x_, y_] := N[(N[(x * c), $MachinePrecision] * y), $MachinePrecision]
\left(x \cdot c\right) \cdot y
Derivation
  1. Initial program 41.2%

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

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

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

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

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

      \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log \mathsf{E}\left(\right)\right)\right) \]
    5. lower-E.f6455.9%

      \[\leadsto c \cdot \left(x \cdot \left(y \cdot \log e\right)\right) \]
  4. Applied rewrites55.9%

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

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

      \[\leadsto c \cdot \left(x \cdot \color{blue}{\left(y \cdot \log e\right)}\right) \]
    3. associate-*r*N/A

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

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

      \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot \log e\right) \]
    6. lift-E.f64N/A

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

      \[\leadsto \left(c \cdot x\right) \cdot \left(y \cdot 1\right) \]
    8. *-rgt-identityN/A

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

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

      \[\leadsto \left(x \cdot c\right) \cdot y \]
    11. lower-*.f6459.0%

      \[\leadsto \left(x \cdot c\right) \cdot y \]
  6. Applied rewrites59.0%

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

Developer Target 1: 93.4% accurate, 1.4× speedup?

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

Reproduce

?
herbie shell --seed 2025226 
(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)))))