System.Random.MWC.Distributions:truncatedExp from mwc-random-0.13.3.2

Percentage Accurate: 61.7% → 98.5%
Time: 20.3s
Alternatives: 9
Speedup: 226.0×

Specification

?
\[\begin{array}{l} \\ x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (- x (/ (log (+ (- 1.0 y) (* y (exp z)))) t)))
double code(double x, double y, double z, double t) {
	return x - (log(((1.0 - y) + (y * exp(z)))) / t);
}
real(8) function code(x, y, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    code = x - (log(((1.0d0 - y) + (y * exp(z)))) / t)
end function
public static double code(double x, double y, double z, double t) {
	return x - (Math.log(((1.0 - y) + (y * Math.exp(z)))) / t);
}
def code(x, y, z, t):
	return x - (math.log(((1.0 - y) + (y * math.exp(z)))) / t)
function code(x, y, z, t)
	return Float64(x - Float64(log(Float64(Float64(1.0 - y) + Float64(y * exp(z)))) / t))
end
function tmp = code(x, y, z, t)
	tmp = x - (log(((1.0 - y) + (y * exp(z)))) / t);
end
code[x_, y_, z_, t_] := N[(x - N[(N[Log[N[(N[(1.0 - y), $MachinePrecision] + N[(y * N[Exp[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

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

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 9 alternatives:

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

Initial Program: 61.7% accurate, 1.0× speedup?

\[\begin{array}{l} \\ x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (- x (/ (log (+ (- 1.0 y) (* y (exp z)))) t)))
double code(double x, double y, double z, double t) {
	return x - (log(((1.0 - y) + (y * exp(z)))) / t);
}
real(8) function code(x, y, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    code = x - (log(((1.0d0 - y) + (y * exp(z)))) / t)
end function
public static double code(double x, double y, double z, double t) {
	return x - (Math.log(((1.0 - y) + (y * Math.exp(z)))) / t);
}
def code(x, y, z, t):
	return x - (math.log(((1.0 - y) + (y * math.exp(z)))) / t)
function code(x, y, z, t)
	return Float64(x - Float64(log(Float64(Float64(1.0 - y) + Float64(y * exp(z)))) / t))
end
function tmp = code(x, y, z, t)
	tmp = x - (log(((1.0 - y) + (y * exp(z)))) / t);
end
code[x_, y_, z_, t_] := N[(x - N[(N[Log[N[(N[(1.0 - y), $MachinePrecision] + N[(y * N[Exp[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

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

Alternative 1: 98.5% accurate, 1.0× speedup?

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

\\
x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}
\end{array}
Derivation
  1. Initial program 64.1%

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

    \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 + y \cdot e^{z}\right) - y\right)}}{t} \]
  4. Step-by-step derivation
    1. sub-negN/A

      \[\leadsto x - \frac{\log \color{blue}{\left(\left(1 + y \cdot e^{z}\right) + \left(\mathsf{neg}\left(y\right)\right)\right)}}{t} \]
    2. associate-+l+N/A

      \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(y \cdot e^{z} + \left(\mathsf{neg}\left(y\right)\right)\right)\right)}}{t} \]
    3. *-rgt-identityN/A

      \[\leadsto x - \frac{\log \left(1 + \left(y \cdot e^{z} + \color{blue}{\left(\mathsf{neg}\left(y\right)\right) \cdot 1}\right)\right)}{t} \]
    4. cancel-sign-sub-invN/A

      \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(y \cdot e^{z} - y \cdot 1\right)}\right)}{t} \]
    5. distribute-lft-out--N/A

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

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(y \cdot \left(e^{z} - 1\right)\right)}}{t} \]
    7. lower-*.f64N/A

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
    8. lower-expm1.f6499.4

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
  5. Simplified99.4%

    \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}{t} \]
  6. Add Preprocessing

Alternative 2: 93.3% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(1 - y\right) + y \cdot e^{z}\\ \mathbf{if}\;t\_1 \leq 0:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\ \mathbf{elif}\;t\_1 \leq 1:\\ \;\;\;\;x - \frac{y \cdot \mathsf{expm1}\left(z\right)}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{2}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (let* ((t_1 (+ (- 1.0 y) (* y (exp z)))))
   (if (<= t_1 0.0)
     (- x (/ (log1p (* y z)) t))
     (if (<= t_1 1.0) (- x (/ (* y (expm1 z)) t)) (- x (/ 2.0 t))))))
double code(double x, double y, double z, double t) {
	double t_1 = (1.0 - y) + (y * exp(z));
	double tmp;
	if (t_1 <= 0.0) {
		tmp = x - (log1p((y * z)) / t);
	} else if (t_1 <= 1.0) {
		tmp = x - ((y * expm1(z)) / t);
	} else {
		tmp = x - (2.0 / t);
	}
	return tmp;
}
public static double code(double x, double y, double z, double t) {
	double t_1 = (1.0 - y) + (y * Math.exp(z));
	double tmp;
	if (t_1 <= 0.0) {
		tmp = x - (Math.log1p((y * z)) / t);
	} else if (t_1 <= 1.0) {
		tmp = x - ((y * Math.expm1(z)) / t);
	} else {
		tmp = x - (2.0 / t);
	}
	return tmp;
}
def code(x, y, z, t):
	t_1 = (1.0 - y) + (y * math.exp(z))
	tmp = 0
	if t_1 <= 0.0:
		tmp = x - (math.log1p((y * z)) / t)
	elif t_1 <= 1.0:
		tmp = x - ((y * math.expm1(z)) / t)
	else:
		tmp = x - (2.0 / t)
	return tmp
function code(x, y, z, t)
	t_1 = Float64(Float64(1.0 - y) + Float64(y * exp(z)))
	tmp = 0.0
	if (t_1 <= 0.0)
		tmp = Float64(x - Float64(log1p(Float64(y * z)) / t));
	elseif (t_1 <= 1.0)
		tmp = Float64(x - Float64(Float64(y * expm1(z)) / t));
	else
		tmp = Float64(x - Float64(2.0 / t));
	end
	return tmp
end
code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[(1.0 - y), $MachinePrecision] + N[(y * N[Exp[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, 0.0], N[(x - N[(N[Log[1 + N[(y * z), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$1, 1.0], N[(x - N[(N[(y * N[(Exp[z] - 1), $MachinePrecision]), $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision], N[(x - N[(2.0 / t), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(1 - y\right) + y \cdot e^{z}\\
\mathbf{if}\;t\_1 \leq 0:\\
\;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\

\mathbf{elif}\;t\_1 \leq 1:\\
\;\;\;\;x - \frac{y \cdot \mathsf{expm1}\left(z\right)}{t}\\

\mathbf{else}:\\
\;\;\;\;x - \frac{2}{t}\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (+.f64 (-.f64 #s(literal 1 binary64) y) (*.f64 y (exp.f64 z))) < 0.0

    1. Initial program 2.1%

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

      \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 + y \cdot e^{z}\right) - y\right)}}{t} \]
    4. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto x - \frac{\log \color{blue}{\left(\left(1 + y \cdot e^{z}\right) + \left(\mathsf{neg}\left(y\right)\right)\right)}}{t} \]
      2. associate-+l+N/A

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(y \cdot e^{z} + \left(\mathsf{neg}\left(y\right)\right)\right)\right)}}{t} \]
      3. *-rgt-identityN/A

        \[\leadsto x - \frac{\log \left(1 + \left(y \cdot e^{z} + \color{blue}{\left(\mathsf{neg}\left(y\right)\right) \cdot 1}\right)\right)}{t} \]
      4. cancel-sign-sub-invN/A

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(y \cdot e^{z} - y \cdot 1\right)}\right)}{t} \]
      5. distribute-lft-out--N/A

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

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(y \cdot \left(e^{z} - 1\right)\right)}}{t} \]
      7. lower-*.f64N/A

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      8. lower-expm1.f6499.9

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    5. Simplified99.9%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}{t} \]
    6. Taylor expanded in z around 0

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]
    7. Step-by-step derivation
      1. lower-*.f6499.9

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]
    8. Simplified99.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]

    if 0.0 < (+.f64 (-.f64 #s(literal 1 binary64) y) (*.f64 y (exp.f64 z))) < 1

    1. Initial program 84.0%

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

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

        \[\leadsto x - \frac{\color{blue}{y \cdot \left(e^{z} - 1\right)}}{t} \]
      2. lower-expm1.f6499.1

        \[\leadsto x - \frac{y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}}{t} \]
    5. Simplified99.1%

      \[\leadsto x - \frac{\color{blue}{y \cdot \mathsf{expm1}\left(z\right)}}{t} \]

    if 1 < (+.f64 (-.f64 #s(literal 1 binary64) y) (*.f64 y (exp.f64 z)))

    1. Initial program 98.7%

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

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

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

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

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

        \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}{t} \]
      6. remove-double-negN/A

        \[\leadsto x - \frac{\color{blue}{\mathsf{neg}\left(\left(\mathsf{neg}\left(\log \left(\left(1 - y\right) + y \cdot e^{z}\right)\right)\right)\right)}}{t} \]
      7. remove-double-negN/A

        \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}{t} \]
      8. clear-numN/A

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}} \]
      9. lower-/.f64N/A

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}} \]
      10. lower-/.f6498.8

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

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

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

        \[\leadsto x - \frac{1}{\frac{t}{\log \left(\color{blue}{\left(1 - y\right)} + y \cdot e^{z}\right)}} \]
      14. sub-negN/A

        \[\leadsto x - \frac{1}{\frac{t}{\log \left(\color{blue}{\left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)} + y \cdot e^{z}\right)}} \]
      15. associate-+l+N/A

        \[\leadsto x - \frac{1}{\frac{t}{\log \color{blue}{\left(1 + \left(\left(\mathsf{neg}\left(y\right)\right) + y \cdot e^{z}\right)\right)}}} \]
      16. lower-log1p.f64N/A

        \[\leadsto x - \frac{1}{\frac{t}{\color{blue}{\mathsf{log1p}\left(\left(\mathsf{neg}\left(y\right)\right) + y \cdot e^{z}\right)}}} \]
      17. +-commutativeN/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(\mathsf{neg}\left(y\right)\right)}\right)}} \]
      18. lift-*.f64N/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z}} + \left(\mathsf{neg}\left(y\right)\right)\right)}} \]
      19. lower-fma.f64N/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, e^{z}, \mathsf{neg}\left(y\right)\right)}\right)}} \]
    4. Applied egg-rr99.0%

      \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(\mathsf{fma}\left(y, e^{z}, -y\right)\right)}}} \]
    5. Step-by-step derivation
      1. lift-exp.f64N/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \color{blue}{e^{z}} + \left(\mathsf{neg}\left(y\right)\right)\right)}} \]
      2. neg-mul-1N/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}} \]
      3. *-commutativeN/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{y \cdot -1}\right)}} \]
      4. distribute-lft-inN/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} + -1\right)}\right)}} \]
      5. metadata-evalN/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \left(e^{z} + \color{blue}{\left(\mathsf{neg}\left(1\right)\right)}\right)\right)}} \]
      6. sub-negN/A

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

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

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}} \]
      9. *-commutativeN/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{\mathsf{expm1}\left(z\right) \cdot y}\right)}} \]
      10. lower-*.f6499.9

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{\mathsf{expm1}\left(z\right) \cdot y}\right)}} \]
    6. Applied egg-rr99.9%

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

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

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

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

        \[\leadsto x - \frac{1}{\frac{\color{blue}{\left(y \cdot t\right)} \cdot \frac{1}{2} + \frac{t}{e^{z} - 1}}{y}} \]
      4. associate-*l*N/A

        \[\leadsto x - \frac{1}{\frac{\color{blue}{y \cdot \left(t \cdot \frac{1}{2}\right)} + \frac{t}{e^{z} - 1}}{y}} \]
      5. metadata-evalN/A

        \[\leadsto x - \frac{1}{\frac{y \cdot \left(t \cdot \color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)}\right) + \frac{t}{e^{z} - 1}}{y}} \]
      6. distribute-rgt-neg-inN/A

        \[\leadsto x - \frac{1}{\frac{y \cdot \color{blue}{\left(\mathsf{neg}\left(t \cdot \frac{-1}{2}\right)\right)} + \frac{t}{e^{z} - 1}}{y}} \]
      7. *-commutativeN/A

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

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

        \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, \mathsf{neg}\left(\color{blue}{t \cdot \frac{-1}{2}}\right), \frac{t}{e^{z} - 1}\right)}{y}} \]
      10. distribute-rgt-neg-inN/A

        \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, \color{blue}{t \cdot \left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)}, \frac{t}{e^{z} - 1}\right)}{y}} \]
      11. metadata-evalN/A

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

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

        \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, t \cdot \frac{1}{2}, \color{blue}{\frac{t}{e^{z} - 1}}\right)}{y}} \]
      14. lower-expm1.f6465.1

        \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, t \cdot 0.5, \frac{t}{\color{blue}{\mathsf{expm1}\left(z\right)}}\right)}{y}} \]
    9. Simplified65.1%

      \[\leadsto x - \frac{1}{\color{blue}{\frac{\mathsf{fma}\left(y, t \cdot 0.5, \frac{t}{\mathsf{expm1}\left(z\right)}\right)}{y}}} \]
    10. Taylor expanded in y around inf

      \[\leadsto x - \color{blue}{\frac{2}{t}} \]
    11. Step-by-step derivation
      1. lower-/.f6465.1

        \[\leadsto x - \color{blue}{\frac{2}{t}} \]
    12. Simplified65.1%

      \[\leadsto x - \color{blue}{\frac{2}{t}} \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 3: 94.6% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\left(1 - y\right) + y \cdot e^{z} \leq 0:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\ \mathbf{else}:\\ \;\;\;\;x + \frac{-1}{\frac{\mathsf{fma}\left(0.5, y \cdot t, \frac{t}{\mathsf{expm1}\left(z\right)}\right)}{y}}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= (+ (- 1.0 y) (* y (exp z))) 0.0)
   (- x (/ (log1p (* y z)) t))
   (+ x (/ -1.0 (/ (fma 0.5 (* y t) (/ t (expm1 z))) y)))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (((1.0 - y) + (y * exp(z))) <= 0.0) {
		tmp = x - (log1p((y * z)) / t);
	} else {
		tmp = x + (-1.0 / (fma(0.5, (y * t), (t / expm1(z))) / y));
	}
	return tmp;
}
function code(x, y, z, t)
	tmp = 0.0
	if (Float64(Float64(1.0 - y) + Float64(y * exp(z))) <= 0.0)
		tmp = Float64(x - Float64(log1p(Float64(y * z)) / t));
	else
		tmp = Float64(x + Float64(-1.0 / Float64(fma(0.5, Float64(y * t), Float64(t / expm1(z))) / y)));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[N[(N[(1.0 - y), $MachinePrecision] + N[(y * N[Exp[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.0], N[(x - N[(N[Log[1 + N[(y * z), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision], N[(x + N[(-1.0 / N[(N[(0.5 * N[(y * t), $MachinePrecision] + N[(t / N[(Exp[z] - 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\left(1 - y\right) + y \cdot e^{z} \leq 0:\\
\;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\

\mathbf{else}:\\
\;\;\;\;x + \frac{-1}{\frac{\mathsf{fma}\left(0.5, y \cdot t, \frac{t}{\mathsf{expm1}\left(z\right)}\right)}{y}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (-.f64 #s(literal 1 binary64) y) (*.f64 y (exp.f64 z))) < 0.0

    1. Initial program 2.1%

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

      \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 + y \cdot e^{z}\right) - y\right)}}{t} \]
    4. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto x - \frac{\log \color{blue}{\left(\left(1 + y \cdot e^{z}\right) + \left(\mathsf{neg}\left(y\right)\right)\right)}}{t} \]
      2. associate-+l+N/A

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(y \cdot e^{z} + \left(\mathsf{neg}\left(y\right)\right)\right)\right)}}{t} \]
      3. *-rgt-identityN/A

        \[\leadsto x - \frac{\log \left(1 + \left(y \cdot e^{z} + \color{blue}{\left(\mathsf{neg}\left(y\right)\right) \cdot 1}\right)\right)}{t} \]
      4. cancel-sign-sub-invN/A

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(y \cdot e^{z} - y \cdot 1\right)}\right)}{t} \]
      5. distribute-lft-out--N/A

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

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(y \cdot \left(e^{z} - 1\right)\right)}}{t} \]
      7. lower-*.f64N/A

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      8. lower-expm1.f6499.9

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    5. Simplified99.9%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}{t} \]
    6. Taylor expanded in z around 0

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]
    7. Step-by-step derivation
      1. lower-*.f6499.9

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]
    8. Simplified99.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]

    if 0.0 < (+.f64 (-.f64 #s(literal 1 binary64) y) (*.f64 y (exp.f64 z)))

    1. Initial program 86.1%

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

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

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

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

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

        \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}{t} \]
      6. remove-double-negN/A

        \[\leadsto x - \frac{\color{blue}{\mathsf{neg}\left(\left(\mathsf{neg}\left(\log \left(\left(1 - y\right) + y \cdot e^{z}\right)\right)\right)\right)}}{t} \]
      7. remove-double-negN/A

        \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}{t} \]
      8. clear-numN/A

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}} \]
      9. lower-/.f64N/A

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}} \]
      10. lower-/.f6486.1

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

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

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

        \[\leadsto x - \frac{1}{\frac{t}{\log \left(\color{blue}{\left(1 - y\right)} + y \cdot e^{z}\right)}} \]
      14. sub-negN/A

        \[\leadsto x - \frac{1}{\frac{t}{\log \left(\color{blue}{\left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)} + y \cdot e^{z}\right)}} \]
      15. associate-+l+N/A

        \[\leadsto x - \frac{1}{\frac{t}{\log \color{blue}{\left(1 + \left(\left(\mathsf{neg}\left(y\right)\right) + y \cdot e^{z}\right)\right)}}} \]
      16. lower-log1p.f64N/A

        \[\leadsto x - \frac{1}{\frac{t}{\color{blue}{\mathsf{log1p}\left(\left(\mathsf{neg}\left(y\right)\right) + y \cdot e^{z}\right)}}} \]
      17. +-commutativeN/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(\mathsf{neg}\left(y\right)\right)}\right)}} \]
      18. lift-*.f64N/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z}} + \left(\mathsf{neg}\left(y\right)\right)\right)}} \]
      19. lower-fma.f64N/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, e^{z}, \mathsf{neg}\left(y\right)\right)}\right)}} \]
    4. Applied egg-rr94.2%

      \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(\mathsf{fma}\left(y, e^{z}, -y\right)\right)}}} \]
    5. Taylor expanded in y around 0

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

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

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

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

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

        \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(\frac{1}{2}, y \cdot t, \color{blue}{\frac{t}{e^{z} - 1}}\right)}{y}} \]
      6. lower-expm1.f6495.0

        \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(0.5, y \cdot t, \frac{t}{\color{blue}{\mathsf{expm1}\left(z\right)}}\right)}{y}} \]
    7. Simplified95.0%

      \[\leadsto x - \frac{1}{\color{blue}{\frac{\mathsf{fma}\left(0.5, y \cdot t, \frac{t}{\mathsf{expm1}\left(z\right)}\right)}{y}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification96.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(1 - y\right) + y \cdot e^{z} \leq 0:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\ \mathbf{else}:\\ \;\;\;\;x + \frac{-1}{\frac{\mathsf{fma}\left(0.5, y \cdot t, \frac{t}{\mathsf{expm1}\left(z\right)}\right)}{y}}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 89.7% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\left(1 - y\right) + y \cdot e^{z} \leq 0:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\ \mathbf{else}:\\ \;\;\;\;x + \frac{-1}{\frac{\frac{\mathsf{fma}\left(z, 0.5 \cdot \left(y \cdot t - t\right), t\right)}{z}}{y}}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= (+ (- 1.0 y) (* y (exp z))) 0.0)
   (- x (/ (log1p (* y z)) t))
   (+ x (/ -1.0 (/ (/ (fma z (* 0.5 (- (* y t) t)) t) z) y)))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (((1.0 - y) + (y * exp(z))) <= 0.0) {
		tmp = x - (log1p((y * z)) / t);
	} else {
		tmp = x + (-1.0 / ((fma(z, (0.5 * ((y * t) - t)), t) / z) / y));
	}
	return tmp;
}
function code(x, y, z, t)
	tmp = 0.0
	if (Float64(Float64(1.0 - y) + Float64(y * exp(z))) <= 0.0)
		tmp = Float64(x - Float64(log1p(Float64(y * z)) / t));
	else
		tmp = Float64(x + Float64(-1.0 / Float64(Float64(fma(z, Float64(0.5 * Float64(Float64(y * t) - t)), t) / z) / y)));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[N[(N[(1.0 - y), $MachinePrecision] + N[(y * N[Exp[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.0], N[(x - N[(N[Log[1 + N[(y * z), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision], N[(x + N[(-1.0 / N[(N[(N[(z * N[(0.5 * N[(N[(y * t), $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision] + t), $MachinePrecision] / z), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\left(1 - y\right) + y \cdot e^{z} \leq 0:\\
\;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\

\mathbf{else}:\\
\;\;\;\;x + \frac{-1}{\frac{\frac{\mathsf{fma}\left(z, 0.5 \cdot \left(y \cdot t - t\right), t\right)}{z}}{y}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (-.f64 #s(literal 1 binary64) y) (*.f64 y (exp.f64 z))) < 0.0

    1. Initial program 2.1%

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

      \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 + y \cdot e^{z}\right) - y\right)}}{t} \]
    4. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto x - \frac{\log \color{blue}{\left(\left(1 + y \cdot e^{z}\right) + \left(\mathsf{neg}\left(y\right)\right)\right)}}{t} \]
      2. associate-+l+N/A

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(y \cdot e^{z} + \left(\mathsf{neg}\left(y\right)\right)\right)\right)}}{t} \]
      3. *-rgt-identityN/A

        \[\leadsto x - \frac{\log \left(1 + \left(y \cdot e^{z} + \color{blue}{\left(\mathsf{neg}\left(y\right)\right) \cdot 1}\right)\right)}{t} \]
      4. cancel-sign-sub-invN/A

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(y \cdot e^{z} - y \cdot 1\right)}\right)}{t} \]
      5. distribute-lft-out--N/A

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

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(y \cdot \left(e^{z} - 1\right)\right)}}{t} \]
      7. lower-*.f64N/A

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      8. lower-expm1.f6499.9

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    5. Simplified99.9%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}{t} \]
    6. Taylor expanded in z around 0

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]
    7. Step-by-step derivation
      1. lower-*.f6499.9

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]
    8. Simplified99.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]

    if 0.0 < (+.f64 (-.f64 #s(literal 1 binary64) y) (*.f64 y (exp.f64 z)))

    1. Initial program 86.1%

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

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

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

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

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

        \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}{t} \]
      6. remove-double-negN/A

        \[\leadsto x - \frac{\color{blue}{\mathsf{neg}\left(\left(\mathsf{neg}\left(\log \left(\left(1 - y\right) + y \cdot e^{z}\right)\right)\right)\right)}}{t} \]
      7. remove-double-negN/A

        \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}{t} \]
      8. clear-numN/A

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}} \]
      9. lower-/.f64N/A

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}} \]
      10. lower-/.f6486.1

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

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

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

        \[\leadsto x - \frac{1}{\frac{t}{\log \left(\color{blue}{\left(1 - y\right)} + y \cdot e^{z}\right)}} \]
      14. sub-negN/A

        \[\leadsto x - \frac{1}{\frac{t}{\log \left(\color{blue}{\left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)} + y \cdot e^{z}\right)}} \]
      15. associate-+l+N/A

        \[\leadsto x - \frac{1}{\frac{t}{\log \color{blue}{\left(1 + \left(\left(\mathsf{neg}\left(y\right)\right) + y \cdot e^{z}\right)\right)}}} \]
      16. lower-log1p.f64N/A

        \[\leadsto x - \frac{1}{\frac{t}{\color{blue}{\mathsf{log1p}\left(\left(\mathsf{neg}\left(y\right)\right) + y \cdot e^{z}\right)}}} \]
      17. +-commutativeN/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(\mathsf{neg}\left(y\right)\right)}\right)}} \]
      18. lift-*.f64N/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z}} + \left(\mathsf{neg}\left(y\right)\right)\right)}} \]
      19. lower-fma.f64N/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, e^{z}, \mathsf{neg}\left(y\right)\right)}\right)}} \]
    4. Applied egg-rr94.2%

      \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(\mathsf{fma}\left(y, e^{z}, -y\right)\right)}}} \]
    5. Step-by-step derivation
      1. lift-exp.f64N/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \color{blue}{e^{z}} + \left(\mathsf{neg}\left(y\right)\right)\right)}} \]
      2. neg-mul-1N/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}} \]
      3. *-commutativeN/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{y \cdot -1}\right)}} \]
      4. distribute-lft-inN/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} + -1\right)}\right)}} \]
      5. metadata-evalN/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \left(e^{z} + \color{blue}{\left(\mathsf{neg}\left(1\right)\right)}\right)\right)}} \]
      6. sub-negN/A

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

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

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}} \]
      9. *-commutativeN/A

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{\mathsf{expm1}\left(z\right) \cdot y}\right)}} \]
      10. lower-*.f6499.2

        \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{\mathsf{expm1}\left(z\right) \cdot y}\right)}} \]
    6. Applied egg-rr99.2%

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

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

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

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

        \[\leadsto x - \frac{1}{\frac{\color{blue}{\left(y \cdot t\right)} \cdot \frac{1}{2} + \frac{t}{e^{z} - 1}}{y}} \]
      4. associate-*l*N/A

        \[\leadsto x - \frac{1}{\frac{\color{blue}{y \cdot \left(t \cdot \frac{1}{2}\right)} + \frac{t}{e^{z} - 1}}{y}} \]
      5. metadata-evalN/A

        \[\leadsto x - \frac{1}{\frac{y \cdot \left(t \cdot \color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)}\right) + \frac{t}{e^{z} - 1}}{y}} \]
      6. distribute-rgt-neg-inN/A

        \[\leadsto x - \frac{1}{\frac{y \cdot \color{blue}{\left(\mathsf{neg}\left(t \cdot \frac{-1}{2}\right)\right)} + \frac{t}{e^{z} - 1}}{y}} \]
      7. *-commutativeN/A

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

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

        \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, \mathsf{neg}\left(\color{blue}{t \cdot \frac{-1}{2}}\right), \frac{t}{e^{z} - 1}\right)}{y}} \]
      10. distribute-rgt-neg-inN/A

        \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, \color{blue}{t \cdot \left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)}, \frac{t}{e^{z} - 1}\right)}{y}} \]
      11. metadata-evalN/A

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

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

        \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, t \cdot \frac{1}{2}, \color{blue}{\frac{t}{e^{z} - 1}}\right)}{y}} \]
      14. lower-expm1.f6495.0

        \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, t \cdot 0.5, \frac{t}{\color{blue}{\mathsf{expm1}\left(z\right)}}\right)}{y}} \]
    9. Simplified95.0%

      \[\leadsto x - \frac{1}{\color{blue}{\frac{\mathsf{fma}\left(y, t \cdot 0.5, \frac{t}{\mathsf{expm1}\left(z\right)}\right)}{y}}} \]
    10. Taylor expanded in z around 0

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

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

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

        \[\leadsto x - \frac{1}{\frac{\frac{\color{blue}{\mathsf{fma}\left(z, \frac{1}{2} \cdot \left(t \cdot y\right) - \frac{1}{2} \cdot t, t\right)}}{z}}{y}} \]
      4. distribute-lft-out--N/A

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

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

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

        \[\leadsto x - \frac{1}{\frac{\frac{\mathsf{fma}\left(z, \frac{1}{2} \cdot \left(\color{blue}{y \cdot t} - t\right), t\right)}{z}}{y}} \]
      8. lower-*.f6487.9

        \[\leadsto x - \frac{1}{\frac{\frac{\mathsf{fma}\left(z, 0.5 \cdot \left(\color{blue}{y \cdot t} - t\right), t\right)}{z}}{y}} \]
    12. Simplified87.9%

      \[\leadsto x - \frac{1}{\frac{\color{blue}{\frac{\mathsf{fma}\left(z, 0.5 \cdot \left(y \cdot t - t\right), t\right)}{z}}}{y}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification91.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(1 - y\right) + y \cdot e^{z} \leq 0:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\ \mathbf{else}:\\ \;\;\;\;x + \frac{-1}{\frac{\frac{\mathsf{fma}\left(z, 0.5 \cdot \left(y \cdot t - t\right), t\right)}{z}}{y}}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 85.1% accurate, 4.0× speedup?

\[\begin{array}{l} \\ x + \frac{-1}{\frac{\frac{\mathsf{fma}\left(z, 0.5 \cdot \left(y \cdot t - t\right), t\right)}{z}}{y}} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (+ x (/ -1.0 (/ (/ (fma z (* 0.5 (- (* y t) t)) t) z) y))))
double code(double x, double y, double z, double t) {
	return x + (-1.0 / ((fma(z, (0.5 * ((y * t) - t)), t) / z) / y));
}
function code(x, y, z, t)
	return Float64(x + Float64(-1.0 / Float64(Float64(fma(z, Float64(0.5 * Float64(Float64(y * t) - t)), t) / z) / y)))
end
code[x_, y_, z_, t_] := N[(x + N[(-1.0 / N[(N[(N[(z * N[(0.5 * N[(N[(y * t), $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision] + t), $MachinePrecision] / z), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x + \frac{-1}{\frac{\frac{\mathsf{fma}\left(z, 0.5 \cdot \left(y \cdot t - t\right), t\right)}{z}}{y}}
\end{array}
Derivation
  1. Initial program 64.1%

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

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

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

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

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

      \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}{t} \]
    6. remove-double-negN/A

      \[\leadsto x - \frac{\color{blue}{\mathsf{neg}\left(\left(\mathsf{neg}\left(\log \left(\left(1 - y\right) + y \cdot e^{z}\right)\right)\right)\right)}}{t} \]
    7. remove-double-negN/A

      \[\leadsto x - \frac{\color{blue}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}{t} \]
    8. clear-numN/A

      \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}} \]
    9. lower-/.f64N/A

      \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}}} \]
    10. lower-/.f6464.1

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

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

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

      \[\leadsto x - \frac{1}{\frac{t}{\log \left(\color{blue}{\left(1 - y\right)} + y \cdot e^{z}\right)}} \]
    14. sub-negN/A

      \[\leadsto x - \frac{1}{\frac{t}{\log \left(\color{blue}{\left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)} + y \cdot e^{z}\right)}} \]
    15. associate-+l+N/A

      \[\leadsto x - \frac{1}{\frac{t}{\log \color{blue}{\left(1 + \left(\left(\mathsf{neg}\left(y\right)\right) + y \cdot e^{z}\right)\right)}}} \]
    16. lower-log1p.f64N/A

      \[\leadsto x - \frac{1}{\frac{t}{\color{blue}{\mathsf{log1p}\left(\left(\mathsf{neg}\left(y\right)\right) + y \cdot e^{z}\right)}}} \]
    17. +-commutativeN/A

      \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(\mathsf{neg}\left(y\right)\right)}\right)}} \]
    18. lift-*.f64N/A

      \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z}} + \left(\mathsf{neg}\left(y\right)\right)\right)}} \]
    19. lower-fma.f64N/A

      \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, e^{z}, \mathsf{neg}\left(y\right)\right)}\right)}} \]
  4. Applied egg-rr87.1%

    \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(\mathsf{fma}\left(y, e^{z}, -y\right)\right)}}} \]
  5. Step-by-step derivation
    1. lift-exp.f64N/A

      \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \color{blue}{e^{z}} + \left(\mathsf{neg}\left(y\right)\right)\right)}} \]
    2. neg-mul-1N/A

      \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}} \]
    3. *-commutativeN/A

      \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{y \cdot -1}\right)}} \]
    4. distribute-lft-inN/A

      \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} + -1\right)}\right)}} \]
    5. metadata-evalN/A

      \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \left(e^{z} + \color{blue}{\left(\mathsf{neg}\left(1\right)\right)}\right)\right)}} \]
    6. sub-negN/A

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

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

      \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}} \]
    9. *-commutativeN/A

      \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{\mathsf{expm1}\left(z\right) \cdot y}\right)}} \]
    10. lower-*.f6499.4

      \[\leadsto x - \frac{1}{\frac{t}{\mathsf{log1p}\left(\color{blue}{\mathsf{expm1}\left(z\right) \cdot y}\right)}} \]
  6. Applied egg-rr99.4%

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

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

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

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

      \[\leadsto x - \frac{1}{\frac{\color{blue}{\left(y \cdot t\right)} \cdot \frac{1}{2} + \frac{t}{e^{z} - 1}}{y}} \]
    4. associate-*l*N/A

      \[\leadsto x - \frac{1}{\frac{\color{blue}{y \cdot \left(t \cdot \frac{1}{2}\right)} + \frac{t}{e^{z} - 1}}{y}} \]
    5. metadata-evalN/A

      \[\leadsto x - \frac{1}{\frac{y \cdot \left(t \cdot \color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)}\right) + \frac{t}{e^{z} - 1}}{y}} \]
    6. distribute-rgt-neg-inN/A

      \[\leadsto x - \frac{1}{\frac{y \cdot \color{blue}{\left(\mathsf{neg}\left(t \cdot \frac{-1}{2}\right)\right)} + \frac{t}{e^{z} - 1}}{y}} \]
    7. *-commutativeN/A

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

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

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, \mathsf{neg}\left(\color{blue}{t \cdot \frac{-1}{2}}\right), \frac{t}{e^{z} - 1}\right)}{y}} \]
    10. distribute-rgt-neg-inN/A

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, \color{blue}{t \cdot \left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)}, \frac{t}{e^{z} - 1}\right)}{y}} \]
    11. metadata-evalN/A

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

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

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, t \cdot \frac{1}{2}, \color{blue}{\frac{t}{e^{z} - 1}}\right)}{y}} \]
    14. lower-expm1.f6492.1

      \[\leadsto x - \frac{1}{\frac{\mathsf{fma}\left(y, t \cdot 0.5, \frac{t}{\color{blue}{\mathsf{expm1}\left(z\right)}}\right)}{y}} \]
  9. Simplified92.1%

    \[\leadsto x - \frac{1}{\color{blue}{\frac{\mathsf{fma}\left(y, t \cdot 0.5, \frac{t}{\mathsf{expm1}\left(z\right)}\right)}{y}}} \]
  10. Taylor expanded in z around 0

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

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

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

      \[\leadsto x - \frac{1}{\frac{\frac{\color{blue}{\mathsf{fma}\left(z, \frac{1}{2} \cdot \left(t \cdot y\right) - \frac{1}{2} \cdot t, t\right)}}{z}}{y}} \]
    4. distribute-lft-out--N/A

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

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

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

      \[\leadsto x - \frac{1}{\frac{\frac{\mathsf{fma}\left(z, \frac{1}{2} \cdot \left(\color{blue}{y \cdot t} - t\right), t\right)}{z}}{y}} \]
    8. lower-*.f6486.9

      \[\leadsto x - \frac{1}{\frac{\frac{\mathsf{fma}\left(z, 0.5 \cdot \left(\color{blue}{y \cdot t} - t\right), t\right)}{z}}{y}} \]
  12. Simplified86.9%

    \[\leadsto x - \frac{1}{\frac{\color{blue}{\frac{\mathsf{fma}\left(z, 0.5 \cdot \left(y \cdot t - t\right), t\right)}{z}}}{y}} \]
  13. Final simplification86.9%

    \[\leadsto x + \frac{-1}{\frac{\frac{\mathsf{fma}\left(z, 0.5 \cdot \left(y \cdot t - t\right), t\right)}{z}}{y}} \]
  14. Add Preprocessing

Alternative 6: 81.4% accurate, 8.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -3.3 \cdot 10^{-58}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(-y, \frac{z}{t}, x\right)\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -3.3e-58) x (fma (- y) (/ z t) x)))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -3.3e-58) {
		tmp = x;
	} else {
		tmp = fma(-y, (z / t), x);
	}
	return tmp;
}
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -3.3e-58)
		tmp = x;
	else
		tmp = fma(Float64(-y), Float64(z / t), x);
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[z, -3.3e-58], x, N[((-y) * N[(z / t), $MachinePrecision] + x), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -3.3 \cdot 10^{-58}:\\
\;\;\;\;x\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(-y, \frac{z}{t}, x\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -3.30000000000000026e-58

    1. Initial program 79.1%

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

      \[\leadsto x - \frac{\log \color{blue}{1}}{t} \]
    4. Step-by-step derivation
      1. Simplified68.9%

        \[\leadsto x - \frac{\log \color{blue}{1}}{t} \]
      2. Step-by-step derivation
        1. metadata-evalN/A

          \[\leadsto x - \frac{\color{blue}{0}}{t} \]
        2. div0N/A

          \[\leadsto x - \color{blue}{0} \]
        3. --rgt-identity68.9

          \[\leadsto \color{blue}{x} \]
      3. Applied egg-rr68.9%

        \[\leadsto \color{blue}{x} \]

      if -3.30000000000000026e-58 < z

      1. Initial program 56.1%

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

        \[\leadsto x - \frac{\color{blue}{y \cdot z}}{t} \]
      4. Step-by-step derivation
        1. lower-*.f6493.1

          \[\leadsto x - \frac{\color{blue}{y \cdot z}}{t} \]
      5. Simplified93.1%

        \[\leadsto x - \frac{\color{blue}{y \cdot z}}{t} \]
      6. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto x - \frac{\color{blue}{y \cdot z}}{t} \]
        2. lift-/.f64N/A

          \[\leadsto x - \color{blue}{\frac{y \cdot z}{t}} \]
        3. sub-negN/A

          \[\leadsto \color{blue}{x + \left(\mathsf{neg}\left(\frac{y \cdot z}{t}\right)\right)} \]
        4. +-commutativeN/A

          \[\leadsto \color{blue}{\left(\mathsf{neg}\left(\frac{y \cdot z}{t}\right)\right) + x} \]
        5. lift-/.f64N/A

          \[\leadsto \left(\mathsf{neg}\left(\color{blue}{\frac{y \cdot z}{t}}\right)\right) + x \]
        6. lift-*.f64N/A

          \[\leadsto \left(\mathsf{neg}\left(\frac{\color{blue}{y \cdot z}}{t}\right)\right) + x \]
        7. associate-/l*N/A

          \[\leadsto \left(\mathsf{neg}\left(\color{blue}{y \cdot \frac{z}{t}}\right)\right) + x \]
        8. distribute-lft-neg-inN/A

          \[\leadsto \color{blue}{\left(\mathsf{neg}\left(y\right)\right) \cdot \frac{z}{t}} + x \]
        9. lift-neg.f64N/A

          \[\leadsto \color{blue}{\left(\mathsf{neg}\left(y\right)\right)} \cdot \frac{z}{t} + x \]
        10. lower-fma.f64N/A

          \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(y\right), \frac{z}{t}, x\right)} \]
        11. lower-/.f6494.0

          \[\leadsto \mathsf{fma}\left(-y, \color{blue}{\frac{z}{t}}, x\right) \]
      7. Applied egg-rr94.0%

        \[\leadsto \color{blue}{\mathsf{fma}\left(-y, \frac{z}{t}, x\right)} \]
    5. Recombined 2 regimes into one program.
    6. Add Preprocessing

    Alternative 7: 80.7% accurate, 8.7× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -3.3 \cdot 10^{-58}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - \frac{y \cdot z}{t}\\ \end{array} \end{array} \]
    (FPCore (x y z t)
     :precision binary64
     (if (<= z -3.3e-58) x (- x (/ (* y z) t))))
    double code(double x, double y, double z, double t) {
    	double tmp;
    	if (z <= -3.3e-58) {
    		tmp = x;
    	} else {
    		tmp = x - ((y * z) / t);
    	}
    	return tmp;
    }
    
    real(8) function code(x, y, z, t)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        real(8), intent (in) :: z
        real(8), intent (in) :: t
        real(8) :: tmp
        if (z <= (-3.3d-58)) then
            tmp = x
        else
            tmp = x - ((y * z) / t)
        end if
        code = tmp
    end function
    
    public static double code(double x, double y, double z, double t) {
    	double tmp;
    	if (z <= -3.3e-58) {
    		tmp = x;
    	} else {
    		tmp = x - ((y * z) / t);
    	}
    	return tmp;
    }
    
    def code(x, y, z, t):
    	tmp = 0
    	if z <= -3.3e-58:
    		tmp = x
    	else:
    		tmp = x - ((y * z) / t)
    	return tmp
    
    function code(x, y, z, t)
    	tmp = 0.0
    	if (z <= -3.3e-58)
    		tmp = x;
    	else
    		tmp = Float64(x - Float64(Float64(y * z) / t));
    	end
    	return tmp
    end
    
    function tmp_2 = code(x, y, z, t)
    	tmp = 0.0;
    	if (z <= -3.3e-58)
    		tmp = x;
    	else
    		tmp = x - ((y * z) / t);
    	end
    	tmp_2 = tmp;
    end
    
    code[x_, y_, z_, t_] := If[LessEqual[z, -3.3e-58], x, N[(x - N[(N[(y * z), $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;z \leq -3.3 \cdot 10^{-58}:\\
    \;\;\;\;x\\
    
    \mathbf{else}:\\
    \;\;\;\;x - \frac{y \cdot z}{t}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if z < -3.30000000000000026e-58

      1. Initial program 79.1%

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

        \[\leadsto x - \frac{\log \color{blue}{1}}{t} \]
      4. Step-by-step derivation
        1. Simplified68.9%

          \[\leadsto x - \frac{\log \color{blue}{1}}{t} \]
        2. Step-by-step derivation
          1. metadata-evalN/A

            \[\leadsto x - \frac{\color{blue}{0}}{t} \]
          2. div0N/A

            \[\leadsto x - \color{blue}{0} \]
          3. --rgt-identity68.9

            \[\leadsto \color{blue}{x} \]
        3. Applied egg-rr68.9%

          \[\leadsto \color{blue}{x} \]

        if -3.30000000000000026e-58 < z

        1. Initial program 56.1%

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

          \[\leadsto x - \frac{\color{blue}{y \cdot z}}{t} \]
        4. Step-by-step derivation
          1. lower-*.f6493.1

            \[\leadsto x - \frac{\color{blue}{y \cdot z}}{t} \]
        5. Simplified93.1%

          \[\leadsto x - \frac{\color{blue}{y \cdot z}}{t} \]
      5. Recombined 2 regimes into one program.
      6. Add Preprocessing

      Alternative 8: 78.7% accurate, 8.7× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -3.3 \cdot 10^{-58}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - z \cdot \frac{y}{t}\\ \end{array} \end{array} \]
      (FPCore (x y z t)
       :precision binary64
       (if (<= z -3.3e-58) x (- x (* z (/ y t)))))
      double code(double x, double y, double z, double t) {
      	double tmp;
      	if (z <= -3.3e-58) {
      		tmp = x;
      	} else {
      		tmp = x - (z * (y / t));
      	}
      	return tmp;
      }
      
      real(8) function code(x, y, z, t)
          real(8), intent (in) :: x
          real(8), intent (in) :: y
          real(8), intent (in) :: z
          real(8), intent (in) :: t
          real(8) :: tmp
          if (z <= (-3.3d-58)) then
              tmp = x
          else
              tmp = x - (z * (y / t))
          end if
          code = tmp
      end function
      
      public static double code(double x, double y, double z, double t) {
      	double tmp;
      	if (z <= -3.3e-58) {
      		tmp = x;
      	} else {
      		tmp = x - (z * (y / t));
      	}
      	return tmp;
      }
      
      def code(x, y, z, t):
      	tmp = 0
      	if z <= -3.3e-58:
      		tmp = x
      	else:
      		tmp = x - (z * (y / t))
      	return tmp
      
      function code(x, y, z, t)
      	tmp = 0.0
      	if (z <= -3.3e-58)
      		tmp = x;
      	else
      		tmp = Float64(x - Float64(z * Float64(y / t)));
      	end
      	return tmp
      end
      
      function tmp_2 = code(x, y, z, t)
      	tmp = 0.0;
      	if (z <= -3.3e-58)
      		tmp = x;
      	else
      		tmp = x - (z * (y / t));
      	end
      	tmp_2 = tmp;
      end
      
      code[x_, y_, z_, t_] := If[LessEqual[z, -3.3e-58], x, N[(x - N[(z * N[(y / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;z \leq -3.3 \cdot 10^{-58}:\\
      \;\;\;\;x\\
      
      \mathbf{else}:\\
      \;\;\;\;x - z \cdot \frac{y}{t}\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if z < -3.30000000000000026e-58

        1. Initial program 79.1%

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

          \[\leadsto x - \frac{\log \color{blue}{1}}{t} \]
        4. Step-by-step derivation
          1. Simplified68.9%

            \[\leadsto x - \frac{\log \color{blue}{1}}{t} \]
          2. Step-by-step derivation
            1. metadata-evalN/A

              \[\leadsto x - \frac{\color{blue}{0}}{t} \]
            2. div0N/A

              \[\leadsto x - \color{blue}{0} \]
            3. --rgt-identity68.9

              \[\leadsto \color{blue}{x} \]
          3. Applied egg-rr68.9%

            \[\leadsto \color{blue}{x} \]

          if -3.30000000000000026e-58 < z

          1. Initial program 56.1%

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

            \[\leadsto x - \frac{\color{blue}{y \cdot z}}{t} \]
          4. Step-by-step derivation
            1. lower-*.f6493.1

              \[\leadsto x - \frac{\color{blue}{y \cdot z}}{t} \]
          5. Simplified93.1%

            \[\leadsto x - \frac{\color{blue}{y \cdot z}}{t} \]
          6. Step-by-step derivation
            1. *-commutativeN/A

              \[\leadsto x - \frac{\color{blue}{z \cdot y}}{t} \]
            2. associate-/l*N/A

              \[\leadsto x - \color{blue}{z \cdot \frac{y}{t}} \]
            3. lower-*.f64N/A

              \[\leadsto x - \color{blue}{z \cdot \frac{y}{t}} \]
            4. lower-/.f6486.3

              \[\leadsto x - z \cdot \color{blue}{\frac{y}{t}} \]
          7. Applied egg-rr86.3%

            \[\leadsto x - \color{blue}{z \cdot \frac{y}{t}} \]
        5. Recombined 2 regimes into one program.
        6. Add Preprocessing

        Alternative 9: 71.8% accurate, 226.0× speedup?

        \[\begin{array}{l} \\ x \end{array} \]
        (FPCore (x y z t) :precision binary64 x)
        double code(double x, double y, double z, double t) {
        	return x;
        }
        
        real(8) function code(x, y, z, t)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            real(8), intent (in) :: z
            real(8), intent (in) :: t
            code = x
        end function
        
        public static double code(double x, double y, double z, double t) {
        	return x;
        }
        
        def code(x, y, z, t):
        	return x
        
        function code(x, y, z, t)
        	return x
        end
        
        function tmp = code(x, y, z, t)
        	tmp = x;
        end
        
        code[x_, y_, z_, t_] := x
        
        \begin{array}{l}
        
        \\
        x
        \end{array}
        
        Derivation
        1. Initial program 64.1%

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

          \[\leadsto x - \frac{\log \color{blue}{1}}{t} \]
        4. Step-by-step derivation
          1. Simplified77.1%

            \[\leadsto x - \frac{\log \color{blue}{1}}{t} \]
          2. Step-by-step derivation
            1. metadata-evalN/A

              \[\leadsto x - \frac{\color{blue}{0}}{t} \]
            2. div0N/A

              \[\leadsto x - \color{blue}{0} \]
            3. --rgt-identity77.1

              \[\leadsto \color{blue}{x} \]
          3. Applied egg-rr77.1%

            \[\leadsto \color{blue}{x} \]
          4. Add Preprocessing

          Developer Target 1: 75.2% accurate, 1.8× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{-0.5}{y \cdot t}\\ \mathbf{if}\;z < -2.8874623088207947 \cdot 10^{+119}:\\ \;\;\;\;\left(x - \frac{t\_1}{z \cdot z}\right) - t\_1 \cdot \frac{\frac{2}{z}}{z \cdot z}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\log \left(1 + z \cdot y\right)}{t}\\ \end{array} \end{array} \]
          (FPCore (x y z t)
           :precision binary64
           (let* ((t_1 (/ (- 0.5) (* y t))))
             (if (< z -2.8874623088207947e+119)
               (- (- x (/ t_1 (* z z))) (* t_1 (/ (/ 2.0 z) (* z z))))
               (- x (/ (log (+ 1.0 (* z y))) t)))))
          double code(double x, double y, double z, double t) {
          	double t_1 = -0.5 / (y * t);
          	double tmp;
          	if (z < -2.8874623088207947e+119) {
          		tmp = (x - (t_1 / (z * z))) - (t_1 * ((2.0 / z) / (z * z)));
          	} else {
          		tmp = x - (log((1.0 + (z * y))) / t);
          	}
          	return tmp;
          }
          
          real(8) function code(x, y, z, t)
              real(8), intent (in) :: x
              real(8), intent (in) :: y
              real(8), intent (in) :: z
              real(8), intent (in) :: t
              real(8) :: t_1
              real(8) :: tmp
              t_1 = -0.5d0 / (y * t)
              if (z < (-2.8874623088207947d+119)) then
                  tmp = (x - (t_1 / (z * z))) - (t_1 * ((2.0d0 / z) / (z * z)))
              else
                  tmp = x - (log((1.0d0 + (z * y))) / t)
              end if
              code = tmp
          end function
          
          public static double code(double x, double y, double z, double t) {
          	double t_1 = -0.5 / (y * t);
          	double tmp;
          	if (z < -2.8874623088207947e+119) {
          		tmp = (x - (t_1 / (z * z))) - (t_1 * ((2.0 / z) / (z * z)));
          	} else {
          		tmp = x - (Math.log((1.0 + (z * y))) / t);
          	}
          	return tmp;
          }
          
          def code(x, y, z, t):
          	t_1 = -0.5 / (y * t)
          	tmp = 0
          	if z < -2.8874623088207947e+119:
          		tmp = (x - (t_1 / (z * z))) - (t_1 * ((2.0 / z) / (z * z)))
          	else:
          		tmp = x - (math.log((1.0 + (z * y))) / t)
          	return tmp
          
          function code(x, y, z, t)
          	t_1 = Float64(Float64(-0.5) / Float64(y * t))
          	tmp = 0.0
          	if (z < -2.8874623088207947e+119)
          		tmp = Float64(Float64(x - Float64(t_1 / Float64(z * z))) - Float64(t_1 * Float64(Float64(2.0 / z) / Float64(z * z))));
          	else
          		tmp = Float64(x - Float64(log(Float64(1.0 + Float64(z * y))) / t));
          	end
          	return tmp
          end
          
          function tmp_2 = code(x, y, z, t)
          	t_1 = -0.5 / (y * t);
          	tmp = 0.0;
          	if (z < -2.8874623088207947e+119)
          		tmp = (x - (t_1 / (z * z))) - (t_1 * ((2.0 / z) / (z * z)));
          	else
          		tmp = x - (log((1.0 + (z * y))) / t);
          	end
          	tmp_2 = tmp;
          end
          
          code[x_, y_, z_, t_] := Block[{t$95$1 = N[((-0.5) / N[(y * t), $MachinePrecision]), $MachinePrecision]}, If[Less[z, -2.8874623088207947e+119], N[(N[(x - N[(t$95$1 / N[(z * z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(t$95$1 * N[(N[(2.0 / z), $MachinePrecision] / N[(z * z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x - N[(N[Log[N[(1.0 + N[(z * y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          t_1 := \frac{-0.5}{y \cdot t}\\
          \mathbf{if}\;z < -2.8874623088207947 \cdot 10^{+119}:\\
          \;\;\;\;\left(x - \frac{t\_1}{z \cdot z}\right) - t\_1 \cdot \frac{\frac{2}{z}}{z \cdot z}\\
          
          \mathbf{else}:\\
          \;\;\;\;x - \frac{\log \left(1 + z \cdot y\right)}{t}\\
          
          
          \end{array}
          \end{array}
          

          Reproduce

          ?
          herbie shell --seed 2024207 
          (FPCore (x y z t)
            :name "System.Random.MWC.Distributions:truncatedExp from mwc-random-0.13.3.2"
            :precision binary64
          
            :alt
            (! :herbie-platform default (if (< z -288746230882079470000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000) (- (- x (/ (/ (- 1/2) (* y t)) (* z z))) (* (/ (- 1/2) (* y t)) (/ (/ 2 z) (* z z)))) (- x (/ (log (+ 1 (* z y))) t))))
          
            (- x (/ (log (+ (- 1.0 y) (* y (exp z)))) t)))