Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, B

Percentage Accurate: 85.5% → 99.8%
Time: 13.2s
Alternatives: 16
Speedup: 1.9×

Specification

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

\\
\left(x \cdot \log y + z \cdot \log \left(1 - y\right)\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 16 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: 85.5% accurate, 1.0× speedup?

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

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

Alternative 1: 99.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \log y \cdot x - t\right) \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (fma (log1p (- y)) z (- (* (log y) x) t)))
double code(double x, double y, double z, double t) {
	return fma(log1p(-y), z, ((log(y) * x) - t));
}
function code(x, y, z, t)
	return fma(log1p(Float64(-y)), z, Float64(Float64(log(y) * x) - t))
end
code[x_, y_, z_, t_] := N[(N[Log[1 + (-y)], $MachinePrecision] * z + N[(N[(N[Log[y], $MachinePrecision] * x), $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \log y \cdot x - t\right)
\end{array}
Derivation
  1. Initial program 80.7%

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\mathsf{fma}\left(\log \left(1 - y\right), z, x \cdot \log y - t\right)} \]
    8. lift-log.f64N/A

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

      \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 - y\right)}, z, x \cdot \log y - t\right) \]
    10. *-lft-identityN/A

      \[\leadsto \mathsf{fma}\left(\log \left(1 - \color{blue}{1 \cdot y}\right), z, x \cdot \log y - t\right) \]
    11. fp-cancel-sub-sign-invN/A

      \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 + \left(\mathsf{neg}\left(1\right)\right) \cdot y\right)}, z, x \cdot \log y - t\right) \]
    12. distribute-lft-neg-inN/A

      \[\leadsto \mathsf{fma}\left(\log \left(1 + \color{blue}{\left(\mathsf{neg}\left(1 \cdot y\right)\right)}\right), z, x \cdot \log y - t\right) \]
    13. *-lft-identityN/A

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

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{log1p}\left(\mathsf{neg}\left(y\right)\right)}, z, x \cdot \log y - t\right) \]
    15. lower-neg.f64N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(\color{blue}{-y}\right), z, x \cdot \log y - t\right) \]
    16. lower--.f6499.8

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y - t}\right) \]
    17. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y} - t\right) \]
    18. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
    19. lower-*.f6499.8

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
  4. Applied rewrites99.8%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \log y \cdot x - t\right)} \]
  5. Add Preprocessing

Alternative 2: 99.6% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \left(x \cdot \log y + \mathsf{fma}\left(\mathsf{fma}\left(z \cdot \mathsf{fma}\left(-0.25, y, -0.3333333333333333\right), y, -0.5 \cdot z\right), y, -z\right) \cdot y\right) - t \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (-
  (+
   (* x (log y))
   (*
    (fma (fma (* z (fma -0.25 y -0.3333333333333333)) y (* -0.5 z)) y (- z))
    y))
  t))
double code(double x, double y, double z, double t) {
	return ((x * log(y)) + (fma(fma((z * fma(-0.25, y, -0.3333333333333333)), y, (-0.5 * z)), y, -z) * y)) - t;
}
function code(x, y, z, t)
	return Float64(Float64(Float64(x * log(y)) + Float64(fma(fma(Float64(z * fma(-0.25, y, -0.3333333333333333)), y, Float64(-0.5 * z)), y, Float64(-z)) * y)) - t)
end
code[x_, y_, z_, t_] := N[(N[(N[(x * N[Log[y], $MachinePrecision]), $MachinePrecision] + N[(N[(N[(N[(z * N[(-0.25 * y + -0.3333333333333333), $MachinePrecision]), $MachinePrecision] * y + N[(-0.5 * z), $MachinePrecision]), $MachinePrecision] * y + (-z)), $MachinePrecision] * y), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot \log y + \mathsf{fma}\left(\mathsf{fma}\left(z \cdot \mathsf{fma}\left(-0.25, y, -0.3333333333333333\right), y, -0.5 \cdot z\right), y, -z\right) \cdot y\right) - t
\end{array}
Derivation
  1. Initial program 80.7%

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

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

      \[\leadsto \left(x \cdot \log y + \color{blue}{\left(-1 \cdot z + y \cdot \left(\frac{-1}{2} \cdot z + y \cdot \left(\frac{-1}{3} \cdot z + \frac{-1}{4} \cdot \left(y \cdot z\right)\right)\right)\right) \cdot y}\right) - t \]
    2. lower-*.f64N/A

      \[\leadsto \left(x \cdot \log y + \color{blue}{\left(-1 \cdot z + y \cdot \left(\frac{-1}{2} \cdot z + y \cdot \left(\frac{-1}{3} \cdot z + \frac{-1}{4} \cdot \left(y \cdot z\right)\right)\right)\right) \cdot y}\right) - t \]
  5. Applied rewrites99.7%

    \[\leadsto \left(x \cdot \log y + \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(z \cdot \mathsf{fma}\left(-0.25, y, -0.3333333333333333\right), y, -0.5 \cdot z\right), y, -z\right) \cdot y}\right) - t \]
  6. Add Preprocessing

Alternative 3: 99.6% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \left(x \cdot \log y + z \cdot \left(\left(\left(\left(-0.25 \cdot y - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y\right)\right) - t \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (-
  (+
   (* x (log y))
   (* z (* (- (* (- (* (- (* -0.25 y) 0.3333333333333333) y) 0.5) y) 1.0) y)))
  t))
double code(double x, double y, double z, double t) {
	return ((x * log(y)) + (z * (((((((-0.25 * y) - 0.3333333333333333) * y) - 0.5) * y) - 1.0) * y))) - 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(y)) + (z * ((((((((-0.25d0) * y) - 0.3333333333333333d0) * y) - 0.5d0) * y) - 1.0d0) * y))) - t
end function
public static double code(double x, double y, double z, double t) {
	return ((x * Math.log(y)) + (z * (((((((-0.25 * y) - 0.3333333333333333) * y) - 0.5) * y) - 1.0) * y))) - t;
}
def code(x, y, z, t):
	return ((x * math.log(y)) + (z * (((((((-0.25 * y) - 0.3333333333333333) * y) - 0.5) * y) - 1.0) * y))) - t
function code(x, y, z, t)
	return Float64(Float64(Float64(x * log(y)) + Float64(z * Float64(Float64(Float64(Float64(Float64(Float64(Float64(-0.25 * y) - 0.3333333333333333) * y) - 0.5) * y) - 1.0) * y))) - t)
end
function tmp = code(x, y, z, t)
	tmp = ((x * log(y)) + (z * (((((((-0.25 * y) - 0.3333333333333333) * y) - 0.5) * y) - 1.0) * y))) - t;
end
code[x_, y_, z_, t_] := N[(N[(N[(x * N[Log[y], $MachinePrecision]), $MachinePrecision] + N[(z * N[(N[(N[(N[(N[(N[(N[(-0.25 * y), $MachinePrecision] - 0.3333333333333333), $MachinePrecision] * y), $MachinePrecision] - 0.5), $MachinePrecision] * y), $MachinePrecision] - 1.0), $MachinePrecision] * y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]
\begin{array}{l}

\\
\left(x \cdot \log y + z \cdot \left(\left(\left(\left(-0.25 \cdot y - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y\right)\right) - t
\end{array}
Derivation
  1. Initial program 80.7%

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

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

      \[\leadsto \left(x \cdot \log y + z \cdot \color{blue}{\left(\left(y \cdot \left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) - 1\right) \cdot y\right)}\right) - t \]
    2. lower-*.f64N/A

      \[\leadsto \left(x \cdot \log y + z \cdot \color{blue}{\left(\left(y \cdot \left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) - 1\right) \cdot y\right)}\right) - t \]
    3. lower--.f64N/A

      \[\leadsto \left(x \cdot \log y + z \cdot \left(\color{blue}{\left(y \cdot \left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) - 1\right)} \cdot y\right)\right) - t \]
    4. *-commutativeN/A

      \[\leadsto \left(x \cdot \log y + z \cdot \left(\left(\color{blue}{\left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) \cdot y} - 1\right) \cdot y\right)\right) - t \]
    5. lower-*.f64N/A

      \[\leadsto \left(x \cdot \log y + z \cdot \left(\left(\color{blue}{\left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) \cdot y} - 1\right) \cdot y\right)\right) - t \]
    6. lower--.f64N/A

      \[\leadsto \left(x \cdot \log y + z \cdot \left(\left(\color{blue}{\left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right)} \cdot y - 1\right) \cdot y\right)\right) - t \]
    7. *-commutativeN/A

      \[\leadsto \left(x \cdot \log y + z \cdot \left(\left(\left(\color{blue}{\left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) \cdot y} - \frac{1}{2}\right) \cdot y - 1\right) \cdot y\right)\right) - t \]
    8. lower-*.f64N/A

      \[\leadsto \left(x \cdot \log y + z \cdot \left(\left(\left(\color{blue}{\left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) \cdot y} - \frac{1}{2}\right) \cdot y - 1\right) \cdot y\right)\right) - t \]
    9. lower--.f64N/A

      \[\leadsto \left(x \cdot \log y + z \cdot \left(\left(\left(\color{blue}{\left(\frac{-1}{4} \cdot y - \frac{1}{3}\right)} \cdot y - \frac{1}{2}\right) \cdot y - 1\right) \cdot y\right)\right) - t \]
    10. lower-*.f6499.7

      \[\leadsto \left(x \cdot \log y + z \cdot \left(\left(\left(\left(\color{blue}{-0.25 \cdot y} - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y\right)\right) - t \]
  5. Applied rewrites99.7%

    \[\leadsto \left(x \cdot \log y + z \cdot \color{blue}{\left(\left(\left(\left(-0.25 \cdot y - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y\right)}\right) - t \]
  6. Add Preprocessing

Alternative 4: 99.5% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(\mathsf{fma}\left(z \cdot \mathsf{fma}\left(-0.3333333333333333, y, -0.5\right), y, -z\right), y, \mathsf{fma}\left(\log y, x, -t\right)\right) \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (fma
  (fma (* z (fma -0.3333333333333333 y -0.5)) y (- z))
  y
  (fma (log y) x (- t))))
double code(double x, double y, double z, double t) {
	return fma(fma((z * fma(-0.3333333333333333, y, -0.5)), y, -z), y, fma(log(y), x, -t));
}
function code(x, y, z, t)
	return fma(fma(Float64(z * fma(-0.3333333333333333, y, -0.5)), y, Float64(-z)), y, fma(log(y), x, Float64(-t)))
end
code[x_, y_, z_, t_] := N[(N[(N[(z * N[(-0.3333333333333333 * y + -0.5), $MachinePrecision]), $MachinePrecision] * y + (-z)), $MachinePrecision] * y + N[(N[Log[y], $MachinePrecision] * x + (-t)), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(\mathsf{fma}\left(z \cdot \mathsf{fma}\left(-0.3333333333333333, y, -0.5\right), y, -z\right), y, \mathsf{fma}\left(\log y, x, -t\right)\right)
\end{array}
Derivation
  1. Initial program 80.7%

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

    \[\leadsto \color{blue}{\left(x \cdot \log y + y \cdot \left(-1 \cdot z + y \cdot \left(\frac{-1}{2} \cdot z + \frac{-1}{3} \cdot \left(y \cdot z\right)\right)\right)\right) - t} \]
  4. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \color{blue}{\left(y \cdot \left(-1 \cdot z + y \cdot \left(\frac{-1}{2} \cdot z + \frac{-1}{3} \cdot \left(y \cdot z\right)\right)\right) + x \cdot \log y\right)} - t \]
    2. associate--l+N/A

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

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

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

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

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

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

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{\frac{-1}{3} \cdot \left(y \cdot z\right) + \frac{-1}{2} \cdot z}, y, -1 \cdot z\right), y, x \cdot \log y - t\right) \]
    9. associate-*r*N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(\color{blue}{\left(\frac{-1}{3} \cdot y\right) \cdot z} + \frac{-1}{2} \cdot z, y, -1 \cdot z\right), y, x \cdot \log y - t\right) \]
    10. distribute-rgt-outN/A

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

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

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(z \cdot \color{blue}{\mathsf{fma}\left(\frac{-1}{3}, y, \frac{-1}{2}\right)}, y, -1 \cdot z\right), y, x \cdot \log y - t\right) \]
    13. mul-1-negN/A

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

      \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(z \cdot \mathsf{fma}\left(\frac{-1}{3}, y, \frac{-1}{2}\right), y, \color{blue}{-z}\right), y, x \cdot \log y - t\right) \]
  5. Applied rewrites99.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(z \cdot \mathsf{fma}\left(-0.3333333333333333, y, -0.5\right), y, -z\right), y, \mathsf{fma}\left(\log y, x, -t\right)\right)} \]
  6. Add Preprocessing

Alternative 5: 99.4% accurate, 1.7× speedup?

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

\\
\mathsf{fma}\left(z \cdot \mathsf{fma}\left(-0.5, y, -1\right), y, \mathsf{fma}\left(\log y, x, -t\right)\right)
\end{array}
Derivation
  1. Initial program 80.7%

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \mathsf{fma}\left(z \cdot \color{blue}{\mathsf{fma}\left(\frac{-1}{2}, y, -1\right)}, y, x \cdot \log y - t\right) \]
    10. remove-double-negN/A

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

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

      \[\leadsto \mathsf{fma}\left(z \cdot \mathsf{fma}\left(\frac{-1}{2}, y, -1\right), y, \color{blue}{\left(\mathsf{neg}\left(x \cdot \left(-1 \cdot \log y\right)\right)\right)} - t\right) \]
    13. mul-1-negN/A

      \[\leadsto \mathsf{fma}\left(z \cdot \mathsf{fma}\left(\frac{-1}{2}, y, -1\right), y, \left(\mathsf{neg}\left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right)\right) - t\right) \]
    14. log-recN/A

      \[\leadsto \mathsf{fma}\left(z \cdot \mathsf{fma}\left(\frac{-1}{2}, y, -1\right), y, \left(\mathsf{neg}\left(x \cdot \color{blue}{\log \left(\frac{1}{y}\right)}\right)\right) - t\right) \]
    15. mul-1-negN/A

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

      \[\leadsto \mathsf{fma}\left(z \cdot \mathsf{fma}\left(\frac{-1}{2}, y, -1\right), y, -1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) - \color{blue}{t \cdot 1}\right) \]
    17. fp-cancel-sub-sign-invN/A

      \[\leadsto \mathsf{fma}\left(z \cdot \mathsf{fma}\left(\frac{-1}{2}, y, -1\right), y, \color{blue}{-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) + \left(\mathsf{neg}\left(t\right)\right) \cdot 1}\right) \]
  5. Applied rewrites99.4%

    \[\leadsto \color{blue}{\mathsf{fma}\left(z \cdot \mathsf{fma}\left(-0.5, y, -1\right), y, \mathsf{fma}\left(\log y, x, -t\right)\right)} \]
  6. Add Preprocessing

Alternative 6: 89.7% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.42 \cdot 10^{-21} \lor \neg \left(x \leq 3.4 \cdot 10^{-138}\right):\\ \;\;\;\;\mathsf{fma}\left(\log y, x, -t\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, -t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (or (<= x -1.42e-21) (not (<= x 3.4e-138)))
   (fma (log y) x (- t))
   (fma (log1p (- y)) z (- t))))
double code(double x, double y, double z, double t) {
	double tmp;
	if ((x <= -1.42e-21) || !(x <= 3.4e-138)) {
		tmp = fma(log(y), x, -t);
	} else {
		tmp = fma(log1p(-y), z, -t);
	}
	return tmp;
}
function code(x, y, z, t)
	tmp = 0.0
	if ((x <= -1.42e-21) || !(x <= 3.4e-138))
		tmp = fma(log(y), x, Float64(-t));
	else
		tmp = fma(log1p(Float64(-y)), z, Float64(-t));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[Or[LessEqual[x, -1.42e-21], N[Not[LessEqual[x, 3.4e-138]], $MachinePrecision]], N[(N[Log[y], $MachinePrecision] * x + (-t)), $MachinePrecision], N[(N[Log[1 + (-y)], $MachinePrecision] * z + (-t)), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.42 \cdot 10^{-21} \lor \neg \left(x \leq 3.4 \cdot 10^{-138}\right):\\
\;\;\;\;\mathsf{fma}\left(\log y, x, -t\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, -t\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -1.42e-21 or 3.4000000000000001e-138 < x

    1. Initial program 90.9%

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

      \[\leadsto \color{blue}{x \cdot \log y - t} \]
    4. Step-by-step derivation
      1. remove-double-negN/A

        \[\leadsto x \cdot \color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\log y\right)\right)\right)\right)} - t \]
      2. mul-1-negN/A

        \[\leadsto x \cdot \left(\mathsf{neg}\left(\color{blue}{-1 \cdot \log y}\right)\right) - t \]
      3. distribute-rgt-neg-inN/A

        \[\leadsto \color{blue}{\left(\mathsf{neg}\left(x \cdot \left(-1 \cdot \log y\right)\right)\right)} - t \]
      4. mul-1-negN/A

        \[\leadsto \left(\mathsf{neg}\left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right)\right) - t \]
      5. log-recN/A

        \[\leadsto \left(\mathsf{neg}\left(x \cdot \color{blue}{\log \left(\frac{1}{y}\right)}\right)\right) - t \]
      6. mul-1-negN/A

        \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right)} - t \]
      7. *-rgt-identityN/A

        \[\leadsto -1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) - \color{blue}{t \cdot 1} \]
      8. fp-cancel-sub-sign-invN/A

        \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) + \left(\mathsf{neg}\left(t\right)\right) \cdot 1} \]
      9. log-recN/A

        \[\leadsto -1 \cdot \left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right) + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      10. mul-1-negN/A

        \[\leadsto -1 \cdot \left(x \cdot \color{blue}{\left(-1 \cdot \log y\right)}\right) + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      11. *-commutativeN/A

        \[\leadsto -1 \cdot \color{blue}{\left(\left(-1 \cdot \log y\right) \cdot x\right)} + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      12. associate-*r*N/A

        \[\leadsto \color{blue}{\left(-1 \cdot \left(-1 \cdot \log y\right)\right) \cdot x} + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      13. mul-1-negN/A

        \[\leadsto \left(-1 \cdot \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right) \cdot x + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      14. log-recN/A

        \[\leadsto \left(-1 \cdot \color{blue}{\log \left(\frac{1}{y}\right)}\right) \cdot x + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      15. mul-1-negN/A

        \[\leadsto \left(-1 \cdot \log \left(\frac{1}{y}\right)\right) \cdot x + \color{blue}{\left(-1 \cdot t\right)} \cdot 1 \]
      16. *-rgt-identityN/A

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

        \[\leadsto \color{blue}{\mathsf{fma}\left(-1 \cdot \log \left(\frac{1}{y}\right), x, -1 \cdot t\right)} \]
    5. Applied rewrites90.0%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\log y, x, -t\right)} \]

    if -1.42e-21 < x < 3.4000000000000001e-138

    1. Initial program 66.8%

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

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

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

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

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

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

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

        \[\leadsto \color{blue}{\mathsf{fma}\left(\log \left(1 - y\right), z, x \cdot \log y - t\right)} \]
      8. lift-log.f64N/A

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

        \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 - y\right)}, z, x \cdot \log y - t\right) \]
      10. *-lft-identityN/A

        \[\leadsto \mathsf{fma}\left(\log \left(1 - \color{blue}{1 \cdot y}\right), z, x \cdot \log y - t\right) \]
      11. fp-cancel-sub-sign-invN/A

        \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 + \left(\mathsf{neg}\left(1\right)\right) \cdot y\right)}, z, x \cdot \log y - t\right) \]
      12. distribute-lft-neg-inN/A

        \[\leadsto \mathsf{fma}\left(\log \left(1 + \color{blue}{\left(\mathsf{neg}\left(1 \cdot y\right)\right)}\right), z, x \cdot \log y - t\right) \]
      13. *-lft-identityN/A

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

        \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{log1p}\left(\mathsf{neg}\left(y\right)\right)}, z, x \cdot \log y - t\right) \]
      15. lower-neg.f64N/A

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(\color{blue}{-y}\right), z, x \cdot \log y - t\right) \]
      16. lower--.f6499.9

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y - t}\right) \]
      17. lift-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y} - t\right) \]
      18. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
      19. lower-*.f6499.9

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
    4. Applied rewrites99.9%

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

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{-1 \cdot t}\right) \]
    6. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\mathsf{neg}\left(t\right)}\right) \]
      2. lower-neg.f6491.0

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{-t}\right) \]
    7. Applied rewrites91.0%

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{-t}\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification90.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1.42 \cdot 10^{-21} \lor \neg \left(x \leq 3.4 \cdot 10^{-138}\right):\\ \;\;\;\;\mathsf{fma}\left(\log y, x, -t\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, -t\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 89.6% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.42 \cdot 10^{-21} \lor \neg \left(x \leq 3.4 \cdot 10^{-138}\right):\\ \;\;\;\;\mathsf{fma}\left(\log y, x, -t\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\left(\left(\left(-0.25 \cdot y - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (or (<= x -1.42e-21) (not (<= x 3.4e-138)))
   (fma (log y) x (- t))
   (fma
    (* (- (* (- (* (- (* -0.25 y) 0.3333333333333333) y) 0.5) y) 1.0) y)
    z
    (- t))))
double code(double x, double y, double z, double t) {
	double tmp;
	if ((x <= -1.42e-21) || !(x <= 3.4e-138)) {
		tmp = fma(log(y), x, -t);
	} else {
		tmp = fma((((((((-0.25 * y) - 0.3333333333333333) * y) - 0.5) * y) - 1.0) * y), z, -t);
	}
	return tmp;
}
function code(x, y, z, t)
	tmp = 0.0
	if ((x <= -1.42e-21) || !(x <= 3.4e-138))
		tmp = fma(log(y), x, Float64(-t));
	else
		tmp = fma(Float64(Float64(Float64(Float64(Float64(Float64(Float64(-0.25 * y) - 0.3333333333333333) * y) - 0.5) * y) - 1.0) * y), z, Float64(-t));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[Or[LessEqual[x, -1.42e-21], N[Not[LessEqual[x, 3.4e-138]], $MachinePrecision]], N[(N[Log[y], $MachinePrecision] * x + (-t)), $MachinePrecision], N[(N[(N[(N[(N[(N[(N[(N[(-0.25 * y), $MachinePrecision] - 0.3333333333333333), $MachinePrecision] * y), $MachinePrecision] - 0.5), $MachinePrecision] * y), $MachinePrecision] - 1.0), $MachinePrecision] * y), $MachinePrecision] * z + (-t)), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.42 \cdot 10^{-21} \lor \neg \left(x \leq 3.4 \cdot 10^{-138}\right):\\
\;\;\;\;\mathsf{fma}\left(\log y, x, -t\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\left(\left(\left(-0.25 \cdot y - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -1.42e-21 or 3.4000000000000001e-138 < x

    1. Initial program 90.9%

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

      \[\leadsto \color{blue}{x \cdot \log y - t} \]
    4. Step-by-step derivation
      1. remove-double-negN/A

        \[\leadsto x \cdot \color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\log y\right)\right)\right)\right)} - t \]
      2. mul-1-negN/A

        \[\leadsto x \cdot \left(\mathsf{neg}\left(\color{blue}{-1 \cdot \log y}\right)\right) - t \]
      3. distribute-rgt-neg-inN/A

        \[\leadsto \color{blue}{\left(\mathsf{neg}\left(x \cdot \left(-1 \cdot \log y\right)\right)\right)} - t \]
      4. mul-1-negN/A

        \[\leadsto \left(\mathsf{neg}\left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right)\right) - t \]
      5. log-recN/A

        \[\leadsto \left(\mathsf{neg}\left(x \cdot \color{blue}{\log \left(\frac{1}{y}\right)}\right)\right) - t \]
      6. mul-1-negN/A

        \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right)} - t \]
      7. *-rgt-identityN/A

        \[\leadsto -1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) - \color{blue}{t \cdot 1} \]
      8. fp-cancel-sub-sign-invN/A

        \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) + \left(\mathsf{neg}\left(t\right)\right) \cdot 1} \]
      9. log-recN/A

        \[\leadsto -1 \cdot \left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right) + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      10. mul-1-negN/A

        \[\leadsto -1 \cdot \left(x \cdot \color{blue}{\left(-1 \cdot \log y\right)}\right) + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      11. *-commutativeN/A

        \[\leadsto -1 \cdot \color{blue}{\left(\left(-1 \cdot \log y\right) \cdot x\right)} + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      12. associate-*r*N/A

        \[\leadsto \color{blue}{\left(-1 \cdot \left(-1 \cdot \log y\right)\right) \cdot x} + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      13. mul-1-negN/A

        \[\leadsto \left(-1 \cdot \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right) \cdot x + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      14. log-recN/A

        \[\leadsto \left(-1 \cdot \color{blue}{\log \left(\frac{1}{y}\right)}\right) \cdot x + \left(\mathsf{neg}\left(t\right)\right) \cdot 1 \]
      15. mul-1-negN/A

        \[\leadsto \left(-1 \cdot \log \left(\frac{1}{y}\right)\right) \cdot x + \color{blue}{\left(-1 \cdot t\right)} \cdot 1 \]
      16. *-rgt-identityN/A

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

        \[\leadsto \color{blue}{\mathsf{fma}\left(-1 \cdot \log \left(\frac{1}{y}\right), x, -1 \cdot t\right)} \]
    5. Applied rewrites90.0%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\log y, x, -t\right)} \]

    if -1.42e-21 < x < 3.4000000000000001e-138

    1. Initial program 66.8%

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

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

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

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

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

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

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

        \[\leadsto \color{blue}{\mathsf{fma}\left(\log \left(1 - y\right), z, x \cdot \log y - t\right)} \]
      8. lift-log.f64N/A

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

        \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 - y\right)}, z, x \cdot \log y - t\right) \]
      10. *-lft-identityN/A

        \[\leadsto \mathsf{fma}\left(\log \left(1 - \color{blue}{1 \cdot y}\right), z, x \cdot \log y - t\right) \]
      11. fp-cancel-sub-sign-invN/A

        \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 + \left(\mathsf{neg}\left(1\right)\right) \cdot y\right)}, z, x \cdot \log y - t\right) \]
      12. distribute-lft-neg-inN/A

        \[\leadsto \mathsf{fma}\left(\log \left(1 + \color{blue}{\left(\mathsf{neg}\left(1 \cdot y\right)\right)}\right), z, x \cdot \log y - t\right) \]
      13. *-lft-identityN/A

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

        \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{log1p}\left(\mathsf{neg}\left(y\right)\right)}, z, x \cdot \log y - t\right) \]
      15. lower-neg.f64N/A

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(\color{blue}{-y}\right), z, x \cdot \log y - t\right) \]
      16. lower--.f6499.9

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y - t}\right) \]
      17. lift-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y} - t\right) \]
      18. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
      19. lower-*.f6499.9

        \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
    4. Applied rewrites99.9%

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

      \[\leadsto \mathsf{fma}\left(\color{blue}{-1 \cdot y}, z, \log y \cdot x - t\right) \]
    6. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{neg}\left(y\right)}, z, \log y \cdot x - t\right) \]
      2. lower-neg.f6498.8

        \[\leadsto \mathsf{fma}\left(\color{blue}{-y}, z, \log y \cdot x - t\right) \]
    7. Applied rewrites98.8%

      \[\leadsto \mathsf{fma}\left(\color{blue}{-y}, z, \log y \cdot x - t\right) \]
    8. Taylor expanded in x around 0

      \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-1 \cdot t}\right) \]
    9. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{\mathsf{neg}\left(t\right)}\right) \]
      2. lower-neg.f6489.9

        \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-t}\right) \]
    10. Applied rewrites89.9%

      \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-t}\right) \]
    11. Taylor expanded in y around 0

      \[\leadsto \mathsf{fma}\left(\color{blue}{y \cdot \left(y \cdot \left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) - 1\right)}, z, -t\right) \]
    12. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\left(y \cdot \left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) - 1\right) \cdot y}, z, -t\right) \]
      2. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\left(y \cdot \left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) - 1\right) \cdot y}, z, -t\right) \]
      3. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\left(y \cdot \left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) - 1\right)} \cdot y, z, -t\right) \]
      4. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\left(\color{blue}{\left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) \cdot y} - 1\right) \cdot y, z, -t\right) \]
      5. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\left(\color{blue}{\left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) \cdot y} - 1\right) \cdot y, z, -t\right) \]
      6. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left(\left(\color{blue}{\left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right)} \cdot y - 1\right) \cdot y, z, -t\right) \]
      7. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(\left(\left(\color{blue}{\left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) \cdot y} - \frac{1}{2}\right) \cdot y - 1\right) \cdot y, z, -t\right) \]
      8. lower-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\left(\left(\color{blue}{\left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) \cdot y} - \frac{1}{2}\right) \cdot y - 1\right) \cdot y, z, -t\right) \]
      9. lower--.f64N/A

        \[\leadsto \mathsf{fma}\left(\left(\left(\color{blue}{\left(\frac{-1}{4} \cdot y - \frac{1}{3}\right)} \cdot y - \frac{1}{2}\right) \cdot y - 1\right) \cdot y, z, -t\right) \]
      10. lower-*.f6491.0

        \[\leadsto \mathsf{fma}\left(\left(\left(\left(\color{blue}{-0.25 \cdot y} - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right) \]
    13. Applied rewrites91.0%

      \[\leadsto \mathsf{fma}\left(\color{blue}{\left(\left(\left(-0.25 \cdot y - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y}, z, -t\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification90.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1.42 \cdot 10^{-21} \lor \neg \left(x \leq 3.4 \cdot 10^{-138}\right):\\ \;\;\;\;\mathsf{fma}\left(\log y, x, -t\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\left(\left(\left(-0.25 \cdot y - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 99.0% accurate, 1.9× speedup?

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

\\
\mathsf{fma}\left(-y, z, \log y \cdot x - t\right)
\end{array}
Derivation
  1. Initial program 80.7%

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\mathsf{fma}\left(\log \left(1 - y\right), z, x \cdot \log y - t\right)} \]
    8. lift-log.f64N/A

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

      \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 - y\right)}, z, x \cdot \log y - t\right) \]
    10. *-lft-identityN/A

      \[\leadsto \mathsf{fma}\left(\log \left(1 - \color{blue}{1 \cdot y}\right), z, x \cdot \log y - t\right) \]
    11. fp-cancel-sub-sign-invN/A

      \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 + \left(\mathsf{neg}\left(1\right)\right) \cdot y\right)}, z, x \cdot \log y - t\right) \]
    12. distribute-lft-neg-inN/A

      \[\leadsto \mathsf{fma}\left(\log \left(1 + \color{blue}{\left(\mathsf{neg}\left(1 \cdot y\right)\right)}\right), z, x \cdot \log y - t\right) \]
    13. *-lft-identityN/A

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

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{log1p}\left(\mathsf{neg}\left(y\right)\right)}, z, x \cdot \log y - t\right) \]
    15. lower-neg.f64N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(\color{blue}{-y}\right), z, x \cdot \log y - t\right) \]
    16. lower--.f6499.8

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y - t}\right) \]
    17. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y} - t\right) \]
    18. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
    19. lower-*.f6499.8

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
  4. Applied rewrites99.8%

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

    \[\leadsto \mathsf{fma}\left(\color{blue}{-1 \cdot y}, z, \log y \cdot x - t\right) \]
  6. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{neg}\left(y\right)}, z, \log y \cdot x - t\right) \]
    2. lower-neg.f6499.0

      \[\leadsto \mathsf{fma}\left(\color{blue}{-y}, z, \log y \cdot x - t\right) \]
  7. Applied rewrites99.0%

    \[\leadsto \mathsf{fma}\left(\color{blue}{-y}, z, \log y \cdot x - t\right) \]
  8. Final simplification99.0%

    \[\leadsto \mathsf{fma}\left(-y, z, \log y \cdot x - t\right) \]
  9. Add Preprocessing

Alternative 9: 99.0% accurate, 1.9× speedup?

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

\\
\log y \cdot x - \mathsf{fma}\left(z, y, t\right)
\end{array}
Derivation
  1. Initial program 80.7%

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

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

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

      \[\leadsto \left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\log y\right)\right)\right)\right)} + -1 \cdot \left(y \cdot z\right)\right) - t \]
    3. mul-1-negN/A

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

      \[\leadsto \left(\color{blue}{\left(\mathsf{neg}\left(x \cdot \left(-1 \cdot \log y\right)\right)\right)} + -1 \cdot \left(y \cdot z\right)\right) - t \]
    5. mul-1-negN/A

      \[\leadsto \left(\left(\mathsf{neg}\left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right)\right) + -1 \cdot \left(y \cdot z\right)\right) - t \]
    6. log-recN/A

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

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

      \[\leadsto \left(-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) + \color{blue}{\left(y \cdot z\right) \cdot -1}\right) - t \]
    9. cancel-sign-subN/A

      \[\leadsto \color{blue}{\left(-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) - \left(\mathsf{neg}\left(y \cdot z\right)\right) \cdot -1\right)} - t \]
    10. distribute-lft-neg-outN/A

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

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

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

      \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) - \left(\left(\mathsf{neg}\left(-1 \cdot \left(y \cdot z\right)\right)\right) + t\right)} \]
  5. Applied rewrites99.0%

    \[\leadsto \color{blue}{\log y \cdot x - \mathsf{fma}\left(z, y, t\right)} \]
  6. Add Preprocessing

Alternative 10: 58.1% accurate, 5.8× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(\left(\left(\left(-0.25 \cdot y - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right) \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (fma
  (* (- (* (- (* (- (* -0.25 y) 0.3333333333333333) y) 0.5) y) 1.0) y)
  z
  (- t)))
double code(double x, double y, double z, double t) {
	return fma((((((((-0.25 * y) - 0.3333333333333333) * y) - 0.5) * y) - 1.0) * y), z, -t);
}
function code(x, y, z, t)
	return fma(Float64(Float64(Float64(Float64(Float64(Float64(Float64(-0.25 * y) - 0.3333333333333333) * y) - 0.5) * y) - 1.0) * y), z, Float64(-t))
end
code[x_, y_, z_, t_] := N[(N[(N[(N[(N[(N[(N[(N[(-0.25 * y), $MachinePrecision] - 0.3333333333333333), $MachinePrecision] * y), $MachinePrecision] - 0.5), $MachinePrecision] * y), $MachinePrecision] - 1.0), $MachinePrecision] * y), $MachinePrecision] * z + (-t)), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(\left(\left(\left(-0.25 \cdot y - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right)
\end{array}
Derivation
  1. Initial program 80.7%

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\mathsf{fma}\left(\log \left(1 - y\right), z, x \cdot \log y - t\right)} \]
    8. lift-log.f64N/A

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

      \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 - y\right)}, z, x \cdot \log y - t\right) \]
    10. *-lft-identityN/A

      \[\leadsto \mathsf{fma}\left(\log \left(1 - \color{blue}{1 \cdot y}\right), z, x \cdot \log y - t\right) \]
    11. fp-cancel-sub-sign-invN/A

      \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 + \left(\mathsf{neg}\left(1\right)\right) \cdot y\right)}, z, x \cdot \log y - t\right) \]
    12. distribute-lft-neg-inN/A

      \[\leadsto \mathsf{fma}\left(\log \left(1 + \color{blue}{\left(\mathsf{neg}\left(1 \cdot y\right)\right)}\right), z, x \cdot \log y - t\right) \]
    13. *-lft-identityN/A

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

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{log1p}\left(\mathsf{neg}\left(y\right)\right)}, z, x \cdot \log y - t\right) \]
    15. lower-neg.f64N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(\color{blue}{-y}\right), z, x \cdot \log y - t\right) \]
    16. lower--.f6499.8

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y - t}\right) \]
    17. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y} - t\right) \]
    18. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
    19. lower-*.f6499.8

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
  4. Applied rewrites99.8%

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

    \[\leadsto \mathsf{fma}\left(\color{blue}{-1 \cdot y}, z, \log y \cdot x - t\right) \]
  6. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{neg}\left(y\right)}, z, \log y \cdot x - t\right) \]
    2. lower-neg.f6499.0

      \[\leadsto \mathsf{fma}\left(\color{blue}{-y}, z, \log y \cdot x - t\right) \]
  7. Applied rewrites99.0%

    \[\leadsto \mathsf{fma}\left(\color{blue}{-y}, z, \log y \cdot x - t\right) \]
  8. Taylor expanded in x around 0

    \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-1 \cdot t}\right) \]
  9. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{\mathsf{neg}\left(t\right)}\right) \]
    2. lower-neg.f6455.4

      \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-t}\right) \]
  10. Applied rewrites55.4%

    \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-t}\right) \]
  11. Taylor expanded in y around 0

    \[\leadsto \mathsf{fma}\left(\color{blue}{y \cdot \left(y \cdot \left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) - 1\right)}, z, -t\right) \]
  12. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\left(y \cdot \left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) - 1\right) \cdot y}, z, -t\right) \]
    2. lower-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\left(y \cdot \left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) - 1\right) \cdot y}, z, -t\right) \]
    3. lower--.f64N/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\left(y \cdot \left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) - 1\right)} \cdot y, z, -t\right) \]
    4. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\left(\color{blue}{\left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) \cdot y} - 1\right) \cdot y, z, -t\right) \]
    5. lower-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\left(\color{blue}{\left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right) \cdot y} - 1\right) \cdot y, z, -t\right) \]
    6. lower--.f64N/A

      \[\leadsto \mathsf{fma}\left(\left(\color{blue}{\left(y \cdot \left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) - \frac{1}{2}\right)} \cdot y - 1\right) \cdot y, z, -t\right) \]
    7. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\left(\left(\color{blue}{\left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) \cdot y} - \frac{1}{2}\right) \cdot y - 1\right) \cdot y, z, -t\right) \]
    8. lower-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\left(\left(\color{blue}{\left(\frac{-1}{4} \cdot y - \frac{1}{3}\right) \cdot y} - \frac{1}{2}\right) \cdot y - 1\right) \cdot y, z, -t\right) \]
    9. lower--.f64N/A

      \[\leadsto \mathsf{fma}\left(\left(\left(\color{blue}{\left(\frac{-1}{4} \cdot y - \frac{1}{3}\right)} \cdot y - \frac{1}{2}\right) \cdot y - 1\right) \cdot y, z, -t\right) \]
    10. lower-*.f6456.1

      \[\leadsto \mathsf{fma}\left(\left(\left(\left(\color{blue}{-0.25 \cdot y} - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right) \]
  13. Applied rewrites56.1%

    \[\leadsto \mathsf{fma}\left(\color{blue}{\left(\left(\left(-0.25 \cdot y - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y}, z, -t\right) \]
  14. Final simplification56.1%

    \[\leadsto \mathsf{fma}\left(\left(\left(\left(-0.25 \cdot y - 0.3333333333333333\right) \cdot y - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right) \]
  15. Add Preprocessing

Alternative 11: 58.0% accurate, 7.3× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(\left(\left(-0.3333333333333333 \cdot y - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right) \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (fma (* (- (* (- (* -0.3333333333333333 y) 0.5) y) 1.0) y) z (- t)))
double code(double x, double y, double z, double t) {
	return fma((((((-0.3333333333333333 * y) - 0.5) * y) - 1.0) * y), z, -t);
}
function code(x, y, z, t)
	return fma(Float64(Float64(Float64(Float64(Float64(-0.3333333333333333 * y) - 0.5) * y) - 1.0) * y), z, Float64(-t))
end
code[x_, y_, z_, t_] := N[(N[(N[(N[(N[(N[(-0.3333333333333333 * y), $MachinePrecision] - 0.5), $MachinePrecision] * y), $MachinePrecision] - 1.0), $MachinePrecision] * y), $MachinePrecision] * z + (-t)), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(\left(\left(-0.3333333333333333 \cdot y - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right)
\end{array}
Derivation
  1. Initial program 80.7%

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\mathsf{fma}\left(\log \left(1 - y\right), z, x \cdot \log y - t\right)} \]
    8. lift-log.f64N/A

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

      \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 - y\right)}, z, x \cdot \log y - t\right) \]
    10. *-lft-identityN/A

      \[\leadsto \mathsf{fma}\left(\log \left(1 - \color{blue}{1 \cdot y}\right), z, x \cdot \log y - t\right) \]
    11. fp-cancel-sub-sign-invN/A

      \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 + \left(\mathsf{neg}\left(1\right)\right) \cdot y\right)}, z, x \cdot \log y - t\right) \]
    12. distribute-lft-neg-inN/A

      \[\leadsto \mathsf{fma}\left(\log \left(1 + \color{blue}{\left(\mathsf{neg}\left(1 \cdot y\right)\right)}\right), z, x \cdot \log y - t\right) \]
    13. *-lft-identityN/A

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

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{log1p}\left(\mathsf{neg}\left(y\right)\right)}, z, x \cdot \log y - t\right) \]
    15. lower-neg.f64N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(\color{blue}{-y}\right), z, x \cdot \log y - t\right) \]
    16. lower--.f6499.8

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y - t}\right) \]
    17. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y} - t\right) \]
    18. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
    19. lower-*.f6499.8

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
  4. Applied rewrites99.8%

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

    \[\leadsto \mathsf{fma}\left(\color{blue}{-1 \cdot y}, z, \log y \cdot x - t\right) \]
  6. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{neg}\left(y\right)}, z, \log y \cdot x - t\right) \]
    2. lower-neg.f6499.0

      \[\leadsto \mathsf{fma}\left(\color{blue}{-y}, z, \log y \cdot x - t\right) \]
  7. Applied rewrites99.0%

    \[\leadsto \mathsf{fma}\left(\color{blue}{-y}, z, \log y \cdot x - t\right) \]
  8. Taylor expanded in x around 0

    \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-1 \cdot t}\right) \]
  9. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{\mathsf{neg}\left(t\right)}\right) \]
    2. lower-neg.f6455.4

      \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-t}\right) \]
  10. Applied rewrites55.4%

    \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-t}\right) \]
  11. Taylor expanded in y around 0

    \[\leadsto \mathsf{fma}\left(\color{blue}{y \cdot \left(y \cdot \left(\frac{-1}{3} \cdot y - \frac{1}{2}\right) - 1\right)}, z, -t\right) \]
  12. Step-by-step derivation
    1. *-commutativeN/A

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

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

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

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

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

      \[\leadsto \mathsf{fma}\left(\left(\color{blue}{\left(\frac{-1}{3} \cdot y - \frac{1}{2}\right)} \cdot y - 1\right) \cdot y, z, -t\right) \]
    7. lower-*.f6455.9

      \[\leadsto \mathsf{fma}\left(\left(\left(\color{blue}{-0.3333333333333333 \cdot y} - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right) \]
  13. Applied rewrites55.9%

    \[\leadsto \mathsf{fma}\left(\color{blue}{\left(\left(-0.3333333333333333 \cdot y - 0.5\right) \cdot y - 1\right) \cdot y}, z, -t\right) \]
  14. Final simplification55.9%

    \[\leadsto \mathsf{fma}\left(\left(\left(-0.3333333333333333 \cdot y - 0.5\right) \cdot y - 1\right) \cdot y, z, -t\right) \]
  15. Add Preprocessing

Alternative 12: 57.9% accurate, 10.0× speedup?

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

\\
\mathsf{fma}\left(\left(-0.5 \cdot y - 1\right) \cdot y, z, -t\right)
\end{array}
Derivation
  1. Initial program 80.7%

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

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

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

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

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

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

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

      \[\leadsto \color{blue}{\mathsf{fma}\left(\log \left(1 - y\right), z, x \cdot \log y - t\right)} \]
    8. lift-log.f64N/A

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

      \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 - y\right)}, z, x \cdot \log y - t\right) \]
    10. *-lft-identityN/A

      \[\leadsto \mathsf{fma}\left(\log \left(1 - \color{blue}{1 \cdot y}\right), z, x \cdot \log y - t\right) \]
    11. fp-cancel-sub-sign-invN/A

      \[\leadsto \mathsf{fma}\left(\log \color{blue}{\left(1 + \left(\mathsf{neg}\left(1\right)\right) \cdot y\right)}, z, x \cdot \log y - t\right) \]
    12. distribute-lft-neg-inN/A

      \[\leadsto \mathsf{fma}\left(\log \left(1 + \color{blue}{\left(\mathsf{neg}\left(1 \cdot y\right)\right)}\right), z, x \cdot \log y - t\right) \]
    13. *-lft-identityN/A

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

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{log1p}\left(\mathsf{neg}\left(y\right)\right)}, z, x \cdot \log y - t\right) \]
    15. lower-neg.f64N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(\color{blue}{-y}\right), z, x \cdot \log y - t\right) \]
    16. lower--.f6499.8

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y - t}\right) \]
    17. lift-*.f64N/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{x \cdot \log y} - t\right) \]
    18. *-commutativeN/A

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
    19. lower-*.f6499.8

      \[\leadsto \mathsf{fma}\left(\mathsf{log1p}\left(-y\right), z, \color{blue}{\log y \cdot x} - t\right) \]
  4. Applied rewrites99.8%

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

    \[\leadsto \mathsf{fma}\left(\color{blue}{-1 \cdot y}, z, \log y \cdot x - t\right) \]
  6. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \mathsf{fma}\left(\color{blue}{\mathsf{neg}\left(y\right)}, z, \log y \cdot x - t\right) \]
    2. lower-neg.f6499.0

      \[\leadsto \mathsf{fma}\left(\color{blue}{-y}, z, \log y \cdot x - t\right) \]
  7. Applied rewrites99.0%

    \[\leadsto \mathsf{fma}\left(\color{blue}{-y}, z, \log y \cdot x - t\right) \]
  8. Taylor expanded in x around 0

    \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-1 \cdot t}\right) \]
  9. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{\mathsf{neg}\left(t\right)}\right) \]
    2. lower-neg.f6455.4

      \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-t}\right) \]
  10. Applied rewrites55.4%

    \[\leadsto \mathsf{fma}\left(-y, z, \color{blue}{-t}\right) \]
  11. Taylor expanded in y around 0

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

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

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

      \[\leadsto \mathsf{fma}\left(\color{blue}{\left(\frac{-1}{2} \cdot y - 1\right)} \cdot y, z, -t\right) \]
    4. lower-*.f6455.7

      \[\leadsto \mathsf{fma}\left(\left(\color{blue}{-0.5 \cdot y} - 1\right) \cdot y, z, -t\right) \]
  13. Applied rewrites55.7%

    \[\leadsto \mathsf{fma}\left(\color{blue}{\left(-0.5 \cdot y - 1\right) \cdot y}, z, -t\right) \]
  14. Final simplification55.7%

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

Alternative 13: 57.9% accurate, 10.0× speedup?

\[\begin{array}{l} \\ \left(\left(-0.5 \cdot y - 1\right) \cdot z\right) \cdot y - t \end{array} \]
(FPCore (x y z t) :precision binary64 (- (* (* (- (* -0.5 y) 1.0) z) y) t))
double code(double x, double y, double z, double t) {
	return ((((-0.5 * y) - 1.0) * z) * y) - 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 = (((((-0.5d0) * y) - 1.0d0) * z) * y) - t
end function
public static double code(double x, double y, double z, double t) {
	return ((((-0.5 * y) - 1.0) * z) * y) - t;
}
def code(x, y, z, t):
	return ((((-0.5 * y) - 1.0) * z) * y) - t
function code(x, y, z, t)
	return Float64(Float64(Float64(Float64(Float64(-0.5 * y) - 1.0) * z) * y) - t)
end
function tmp = code(x, y, z, t)
	tmp = ((((-0.5 * y) - 1.0) * z) * y) - t;
end
code[x_, y_, z_, t_] := N[(N[(N[(N[(N[(-0.5 * y), $MachinePrecision] - 1.0), $MachinePrecision] * z), $MachinePrecision] * y), $MachinePrecision] - t), $MachinePrecision]
\begin{array}{l}

\\
\left(\left(-0.5 \cdot y - 1\right) \cdot z\right) \cdot y - t
\end{array}
Derivation
  1. Initial program 80.7%

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \mathsf{fma}\left(z \cdot \color{blue}{\mathsf{fma}\left(\frac{-1}{2}, y, -1\right)}, y, x \cdot \log y - t\right) \]
    10. remove-double-negN/A

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

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

      \[\leadsto \mathsf{fma}\left(z \cdot \mathsf{fma}\left(\frac{-1}{2}, y, -1\right), y, \color{blue}{\left(\mathsf{neg}\left(x \cdot \left(-1 \cdot \log y\right)\right)\right)} - t\right) \]
    13. mul-1-negN/A

      \[\leadsto \mathsf{fma}\left(z \cdot \mathsf{fma}\left(\frac{-1}{2}, y, -1\right), y, \left(\mathsf{neg}\left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right)\right) - t\right) \]
    14. log-recN/A

      \[\leadsto \mathsf{fma}\left(z \cdot \mathsf{fma}\left(\frac{-1}{2}, y, -1\right), y, \left(\mathsf{neg}\left(x \cdot \color{blue}{\log \left(\frac{1}{y}\right)}\right)\right) - t\right) \]
    15. mul-1-negN/A

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

      \[\leadsto \mathsf{fma}\left(z \cdot \mathsf{fma}\left(\frac{-1}{2}, y, -1\right), y, -1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) - \color{blue}{t \cdot 1}\right) \]
    17. fp-cancel-sub-sign-invN/A

      \[\leadsto \mathsf{fma}\left(z \cdot \mathsf{fma}\left(\frac{-1}{2}, y, -1\right), y, \color{blue}{-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) + \left(\mathsf{neg}\left(t\right)\right) \cdot 1}\right) \]
  5. Applied rewrites99.4%

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

    \[\leadsto y \cdot \left(z \cdot \left(\frac{-1}{2} \cdot y - 1\right)\right) - \color{blue}{t} \]
  7. Step-by-step derivation
    1. Applied rewrites55.7%

      \[\leadsto \left(\left(-0.5 \cdot y - 1\right) \cdot z\right) \cdot y - \color{blue}{t} \]
    2. Add Preprocessing

    Alternative 14: 48.9% accurate, 11.0× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq -1.02 \cdot 10^{-49} \lor \neg \left(t \leq 6.2 \cdot 10^{-63}\right):\\ \;\;\;\;-t\\ \mathbf{else}:\\ \;\;\;\;\left(-y\right) \cdot z\\ \end{array} \end{array} \]
    (FPCore (x y z t)
     :precision binary64
     (if (or (<= t -1.02e-49) (not (<= t 6.2e-63))) (- t) (* (- y) z)))
    double code(double x, double y, double z, double t) {
    	double tmp;
    	if ((t <= -1.02e-49) || !(t <= 6.2e-63)) {
    		tmp = -t;
    	} else {
    		tmp = -y * z;
    	}
    	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 ((t <= (-1.02d-49)) .or. (.not. (t <= 6.2d-63))) then
            tmp = -t
        else
            tmp = -y * z
        end if
        code = tmp
    end function
    
    public static double code(double x, double y, double z, double t) {
    	double tmp;
    	if ((t <= -1.02e-49) || !(t <= 6.2e-63)) {
    		tmp = -t;
    	} else {
    		tmp = -y * z;
    	}
    	return tmp;
    }
    
    def code(x, y, z, t):
    	tmp = 0
    	if (t <= -1.02e-49) or not (t <= 6.2e-63):
    		tmp = -t
    	else:
    		tmp = -y * z
    	return tmp
    
    function code(x, y, z, t)
    	tmp = 0.0
    	if ((t <= -1.02e-49) || !(t <= 6.2e-63))
    		tmp = Float64(-t);
    	else
    		tmp = Float64(Float64(-y) * z);
    	end
    	return tmp
    end
    
    function tmp_2 = code(x, y, z, t)
    	tmp = 0.0;
    	if ((t <= -1.02e-49) || ~((t <= 6.2e-63)))
    		tmp = -t;
    	else
    		tmp = -y * z;
    	end
    	tmp_2 = tmp;
    end
    
    code[x_, y_, z_, t_] := If[Or[LessEqual[t, -1.02e-49], N[Not[LessEqual[t, 6.2e-63]], $MachinePrecision]], (-t), N[((-y) * z), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;t \leq -1.02 \cdot 10^{-49} \lor \neg \left(t \leq 6.2 \cdot 10^{-63}\right):\\
    \;\;\;\;-t\\
    
    \mathbf{else}:\\
    \;\;\;\;\left(-y\right) \cdot z\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if t < -1.02000000000000009e-49 or 6.19999999999999968e-63 < t

      1. Initial program 91.3%

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

        \[\leadsto \color{blue}{-1 \cdot t} \]
      4. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto \color{blue}{\mathsf{neg}\left(t\right)} \]
        2. lower-neg.f6457.4

          \[\leadsto \color{blue}{-t} \]
      5. Applied rewrites57.4%

        \[\leadsto \color{blue}{-t} \]

      if -1.02000000000000009e-49 < t < 6.19999999999999968e-63

      1. Initial program 68.0%

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

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

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

          \[\leadsto \left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\log y\right)\right)\right)\right)} + -1 \cdot \left(y \cdot z\right)\right) - t \]
        3. mul-1-negN/A

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

          \[\leadsto \left(\color{blue}{\left(\mathsf{neg}\left(x \cdot \left(-1 \cdot \log y\right)\right)\right)} + -1 \cdot \left(y \cdot z\right)\right) - t \]
        5. mul-1-negN/A

          \[\leadsto \left(\left(\mathsf{neg}\left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right)\right) + -1 \cdot \left(y \cdot z\right)\right) - t \]
        6. log-recN/A

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

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

          \[\leadsto \left(-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) + \color{blue}{\left(y \cdot z\right) \cdot -1}\right) - t \]
        9. cancel-sign-subN/A

          \[\leadsto \color{blue}{\left(-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) - \left(\mathsf{neg}\left(y \cdot z\right)\right) \cdot -1\right)} - t \]
        10. distribute-lft-neg-outN/A

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

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

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

          \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) - \left(\left(\mathsf{neg}\left(-1 \cdot \left(y \cdot z\right)\right)\right) + t\right)} \]
      5. Applied rewrites98.7%

        \[\leadsto \color{blue}{\log y \cdot x - \mathsf{fma}\left(z, y, t\right)} \]
      6. Taylor expanded in y around inf

        \[\leadsto -1 \cdot \color{blue}{\left(y \cdot z\right)} \]
      7. Step-by-step derivation
        1. Applied rewrites33.4%

          \[\leadsto \left(-y\right) \cdot \color{blue}{z} \]
      8. Recombined 2 regimes into one program.
      9. Final simplification46.5%

        \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq -1.02 \cdot 10^{-49} \lor \neg \left(t \leq 6.2 \cdot 10^{-63}\right):\\ \;\;\;\;-t\\ \mathbf{else}:\\ \;\;\;\;\left(-y\right) \cdot z\\ \end{array} \]
      10. Add Preprocessing

      Alternative 15: 57.6% accurate, 24.4× speedup?

      \[\begin{array}{l} \\ -\mathsf{fma}\left(z, y, t\right) \end{array} \]
      (FPCore (x y z t) :precision binary64 (- (fma z y t)))
      double code(double x, double y, double z, double t) {
      	return -fma(z, y, t);
      }
      
      function code(x, y, z, t)
      	return Float64(-fma(z, y, t))
      end
      
      code[x_, y_, z_, t_] := (-N[(z * y + t), $MachinePrecision])
      
      \begin{array}{l}
      
      \\
      -\mathsf{fma}\left(z, y, t\right)
      \end{array}
      
      Derivation
      1. Initial program 80.7%

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

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

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

          \[\leadsto \left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\log y\right)\right)\right)\right)} + -1 \cdot \left(y \cdot z\right)\right) - t \]
        3. mul-1-negN/A

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

          \[\leadsto \left(\color{blue}{\left(\mathsf{neg}\left(x \cdot \left(-1 \cdot \log y\right)\right)\right)} + -1 \cdot \left(y \cdot z\right)\right) - t \]
        5. mul-1-negN/A

          \[\leadsto \left(\left(\mathsf{neg}\left(x \cdot \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right)\right) + -1 \cdot \left(y \cdot z\right)\right) - t \]
        6. log-recN/A

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

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

          \[\leadsto \left(-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) + \color{blue}{\left(y \cdot z\right) \cdot -1}\right) - t \]
        9. cancel-sign-subN/A

          \[\leadsto \color{blue}{\left(-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) - \left(\mathsf{neg}\left(y \cdot z\right)\right) \cdot -1\right)} - t \]
        10. distribute-lft-neg-outN/A

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

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

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

          \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \log \left(\frac{1}{y}\right)\right) - \left(\left(\mathsf{neg}\left(-1 \cdot \left(y \cdot z\right)\right)\right) + t\right)} \]
      5. Applied rewrites99.0%

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

        \[\leadsto -1 \cdot \color{blue}{\left(t + y \cdot z\right)} \]
      7. Step-by-step derivation
        1. Applied rewrites55.4%

          \[\leadsto -\mathsf{fma}\left(z, y, t\right) \]
        2. Add Preprocessing

        Alternative 16: 43.4% accurate, 73.3× speedup?

        \[\begin{array}{l} \\ -t \end{array} \]
        (FPCore (x y z t) :precision binary64 (- t))
        double code(double x, double y, double z, double t) {
        	return -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 = -t
        end function
        
        public static double code(double x, double y, double z, double t) {
        	return -t;
        }
        
        def code(x, y, z, t):
        	return -t
        
        function code(x, y, z, t)
        	return Float64(-t)
        end
        
        function tmp = code(x, y, z, t)
        	tmp = -t;
        end
        
        code[x_, y_, z_, t_] := (-t)
        
        \begin{array}{l}
        
        \\
        -t
        \end{array}
        
        Derivation
        1. Initial program 80.7%

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

          \[\leadsto \color{blue}{-1 \cdot t} \]
        4. Step-by-step derivation
          1. mul-1-negN/A

            \[\leadsto \color{blue}{\mathsf{neg}\left(t\right)} \]
          2. lower-neg.f6436.7

            \[\leadsto \color{blue}{-t} \]
        5. Applied rewrites36.7%

          \[\leadsto \color{blue}{-t} \]
        6. Add Preprocessing

        Developer Target 1: 99.5% accurate, 1.3× speedup?

        \[\begin{array}{l} \\ \left(-z\right) \cdot \left(\left(0.5 \cdot \left(y \cdot y\right) + y\right) + \frac{0.3333333333333333}{1 \cdot \left(1 \cdot 1\right)} \cdot \left(y \cdot \left(y \cdot y\right)\right)\right) - \left(t - x \cdot \log y\right) \end{array} \]
        (FPCore (x y z t)
         :precision binary64
         (-
          (*
           (- z)
           (+
            (+ (* 0.5 (* y y)) y)
            (* (/ 0.3333333333333333 (* 1.0 (* 1.0 1.0))) (* y (* y y)))))
          (- t (* x (log y)))))
        double code(double x, double y, double z, double t) {
        	return (-z * (((0.5 * (y * y)) + y) + ((0.3333333333333333 / (1.0 * (1.0 * 1.0))) * (y * (y * y))))) - (t - (x * log(y)));
        }
        
        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 = (-z * (((0.5d0 * (y * y)) + y) + ((0.3333333333333333d0 / (1.0d0 * (1.0d0 * 1.0d0))) * (y * (y * y))))) - (t - (x * log(y)))
        end function
        
        public static double code(double x, double y, double z, double t) {
        	return (-z * (((0.5 * (y * y)) + y) + ((0.3333333333333333 / (1.0 * (1.0 * 1.0))) * (y * (y * y))))) - (t - (x * Math.log(y)));
        }
        
        def code(x, y, z, t):
        	return (-z * (((0.5 * (y * y)) + y) + ((0.3333333333333333 / (1.0 * (1.0 * 1.0))) * (y * (y * y))))) - (t - (x * math.log(y)))
        
        function code(x, y, z, t)
        	return Float64(Float64(Float64(-z) * Float64(Float64(Float64(0.5 * Float64(y * y)) + y) + Float64(Float64(0.3333333333333333 / Float64(1.0 * Float64(1.0 * 1.0))) * Float64(y * Float64(y * y))))) - Float64(t - Float64(x * log(y))))
        end
        
        function tmp = code(x, y, z, t)
        	tmp = (-z * (((0.5 * (y * y)) + y) + ((0.3333333333333333 / (1.0 * (1.0 * 1.0))) * (y * (y * y))))) - (t - (x * log(y)));
        end
        
        code[x_, y_, z_, t_] := N[(N[((-z) * N[(N[(N[(0.5 * N[(y * y), $MachinePrecision]), $MachinePrecision] + y), $MachinePrecision] + N[(N[(0.3333333333333333 / N[(1.0 * N[(1.0 * 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(y * N[(y * y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(t - N[(x * N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \left(-z\right) \cdot \left(\left(0.5 \cdot \left(y \cdot y\right) + y\right) + \frac{0.3333333333333333}{1 \cdot \left(1 \cdot 1\right)} \cdot \left(y \cdot \left(y \cdot y\right)\right)\right) - \left(t - x \cdot \log y\right)
        \end{array}
        

        Reproduce

        ?
        herbie shell --seed 2024329 
        (FPCore (x y z t)
          :name "Numeric.SpecFunctions:invIncompleteBetaWorker from math-functions-0.1.5.2, B"
          :precision binary64
        
          :alt
          (! :herbie-platform default (- (* (- z) (+ (+ (* 1/2 (* y y)) y) (* (/ 1/3 (* 1 (* 1 1))) (* y (* y y))))) (- t (* x (log y)))))
        
          (- (+ (* x (log y)) (* z (log (- 1.0 y)))) t))