Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 11.3s
Alternatives: 10
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))
double code(double x, double y, double z, double t, double a) {
	return ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    code = ((log((x + y)) + log(z)) - t) + ((a - 0.5d0) * log(t))
end function
public static double code(double x, double y, double z, double t, double a) {
	return ((Math.log((x + y)) + Math.log(z)) - t) + ((a - 0.5) * Math.log(t));
}
def code(x, y, z, t, a):
	return ((math.log((x + y)) + math.log(z)) - t) + ((a - 0.5) * math.log(t))
function code(x, y, z, t, a)
	return Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
end
function tmp = code(x, y, z, t, a)
	tmp = ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
end
code[x_, y_, z_, t_, a_] := N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log 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 10 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: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))
double code(double x, double y, double z, double t, double a) {
	return ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    code = ((log((x + y)) + log(z)) - t) + ((a - 0.5d0) * log(t))
end function
public static double code(double x, double y, double z, double t, double a) {
	return ((Math.log((x + y)) + Math.log(z)) - t) + ((a - 0.5) * Math.log(t));
}
def code(x, y, z, t, a):
	return ((math.log((x + y)) + math.log(z)) - t) + ((a - 0.5) * math.log(t))
function code(x, y, z, t, a)
	return Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
end
function tmp = code(x, y, z, t, a)
	tmp = ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
end
code[x_, y_, z_, t_, a_] := N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t
\end{array}

Alternative 1: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))
double code(double x, double y, double z, double t, double a) {
	return ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    code = ((log((x + y)) + log(z)) - t) + ((a - 0.5d0) * log(t))
end function
public static double code(double x, double y, double z, double t, double a) {
	return ((Math.log((x + y)) + Math.log(z)) - t) + ((a - 0.5) * Math.log(t));
}
def code(x, y, z, t, a):
	return ((math.log((x + y)) + math.log(z)) - t) + ((a - 0.5) * math.log(t))
function code(x, y, z, t, a)
	return Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
end
function tmp = code(x, y, z, t, a)
	tmp = ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
end
code[x_, y_, z_, t_, a_] := N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t
\end{array}
Derivation
  1. Initial program 99.7%

    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
  2. Add Preprocessing
  3. Add Preprocessing

Alternative 2: 84.8% accurate, 0.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{if}\;t\_1 \leq -4000000000000:\\ \;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\ \mathbf{elif}\;t\_1 \leq 500:\\ \;\;\;\;\mathsf{fma}\left(\log t, -0.5 + a, \log \left(z \cdot y\right)\right) - t\\ \mathbf{elif}\;t\_1 \leq 2000:\\ \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log z + \log \left(y + x\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t)))))
   (if (<= t_1 -4000000000000.0)
     (fma (* a (/ (log t) t)) t (- t))
     (if (<= t_1 500.0)
       (- (fma (log t) (+ -0.5 a) (log (* z y))) t)
       (if (<= t_1 2000.0)
         (fma -0.5 (log t) (+ (log z) (log (+ y x))))
         (* (log t) a))))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
	double tmp;
	if (t_1 <= -4000000000000.0) {
		tmp = fma((a * (log(t) / t)), t, -t);
	} else if (t_1 <= 500.0) {
		tmp = fma(log(t), (-0.5 + a), log((z * y))) - t;
	} else if (t_1 <= 2000.0) {
		tmp = fma(-0.5, log(t), (log(z) + log((y + x))));
	} else {
		tmp = log(t) * a;
	}
	return tmp;
}
function code(x, y, z, t, a)
	t_1 = Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
	tmp = 0.0
	if (t_1 <= -4000000000000.0)
		tmp = fma(Float64(a * Float64(log(t) / t)), t, Float64(-t));
	elseif (t_1 <= 500.0)
		tmp = Float64(fma(log(t), Float64(-0.5 + a), log(Float64(z * y))) - t);
	elseif (t_1 <= 2000.0)
		tmp = fma(-0.5, log(t), Float64(log(z) + log(Float64(y + x))));
	else
		tmp = Float64(log(t) * a);
	end
	return tmp
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, -4000000000000.0], N[(N[(a * N[(N[Log[t], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision] * t + (-t)), $MachinePrecision], If[LessEqual[t$95$1, 500.0], N[(N[(N[Log[t], $MachinePrecision] * N[(-0.5 + a), $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[t$95$1, 2000.0], N[(-0.5 * N[Log[t], $MachinePrecision] + N[(N[Log[z], $MachinePrecision] + N[Log[N[(y + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\
\mathbf{if}\;t\_1 \leq -4000000000000:\\
\;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\

\mathbf{elif}\;t\_1 \leq 500:\\
\;\;\;\;\mathsf{fma}\left(\log t, -0.5 + a, \log \left(z \cdot y\right)\right) - t\\

\mathbf{elif}\;t\_1 \leq 2000:\\
\;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log z + \log \left(y + x\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\log t \cdot a\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < -4e12

    1. Initial program 99.8%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Add Preprocessing
    3. Taylor expanded in t around inf

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

        \[\leadsto t \cdot \color{blue}{\left(\left(-1 \cdot \frac{\log \left(\frac{1}{t}\right) \cdot \left(a - \frac{1}{2}\right)}{t} + \left(\frac{\log z}{t} + \frac{\log \left(x + y\right)}{t}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)\right)} \]
      2. metadata-evalN/A

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

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

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

        \[\leadsto \color{blue}{\mathsf{fma}\left(-1 \cdot \frac{\log \left(\frac{1}{t}\right) \cdot \left(a - \frac{1}{2}\right)}{t} + \left(\frac{\log z}{t} + \frac{\log \left(x + y\right)}{t}\right), t, \mathsf{neg}\left(t\right)\right)} \]
    5. Applied rewrites93.2%

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

      \[\leadsto \mathsf{fma}\left(\frac{a \cdot \log t}{t}, t, -t\right) \]
    7. Step-by-step derivation
      1. Applied rewrites92.8%

        \[\leadsto \mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right) \]

      if -4e12 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 500

      1. Initial program 99.0%

        \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift-+.f64N/A

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

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

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

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

          \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\left(\log \left(x + y\right) + \log z\right) - t\right) \cdot \left(\left(\log \left(x + y\right) + \log z\right) - t\right) - \left(\left(a - \frac{1}{2}\right) \cdot \log t\right) \cdot \left(\left(a - \frac{1}{2}\right) \cdot \log t\right)}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right) - \left(a - \frac{1}{2}\right) \cdot \log t}}}} \]
      4. Applied rewrites96.9%

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

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

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

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

          \[\leadsto \left(\log t \cdot \color{blue}{\left(a + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)} + \log \left(y \cdot z\right)\right) - t \]
        4. metadata-evalN/A

          \[\leadsto \left(\log t \cdot \left(a + \color{blue}{\frac{-1}{2}}\right) + \log \left(y \cdot z\right)\right) - t \]
        5. distribute-rgt-inN/A

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

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

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

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

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

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

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

          \[\leadsto \mathsf{fma}\left(\log t, \frac{-1}{2} + a, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
        13. lower-*.f6457.7

          \[\leadsto \mathsf{fma}\left(\log t, -0.5 + a, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
      7. Applied rewrites57.7%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\log t, -0.5 + a, \log \left(z \cdot y\right)\right) - t} \]

      if 500 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 2e3

      1. Initial program 99.7%

        \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift-*.f64N/A

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

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

          \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\left(a - \frac{1}{2}\right)} \]
        4. flip3--N/A

          \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\frac{{a}^{3} - {\frac{1}{2}}^{3}}{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}} \]
        5. clear-numN/A

          \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\frac{1}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
        6. un-div-invN/A

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

          \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
        8. clear-numN/A

          \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{\frac{{a}^{3} - {\frac{1}{2}}^{3}}{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}}}} \]
        9. flip3--N/A

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

          \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\frac{1}{\color{blue}{a - \frac{1}{2}}}} \]
        11. lower-/.f6499.7

          \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
      4. Applied rewrites99.7%

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
      5. Taylor expanded in t around 0

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

          \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log \color{blue}{\left(y + x\right)}\right) + \log z \]
        16. lower-log.f6499.8

          \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log \left(y + x\right)\right) + \color{blue}{\log z} \]
      7. Applied rewrites99.8%

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

        \[\leadsto \log z + \color{blue}{\left(\log \left(x + y\right) + \frac{-1}{2} \cdot \log t\right)} \]
      9. Step-by-step derivation
        1. Applied rewrites97.5%

          \[\leadsto \mathsf{fma}\left(-0.5, \color{blue}{\log t}, \log z + \log \left(y + x\right)\right) \]

        if 2e3 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t)))

        1. Initial program 99.7%

          \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
        2. Add Preprocessing
        3. Taylor expanded in a around inf

          \[\leadsto \color{blue}{a \cdot \log t} \]
        4. Step-by-step derivation
          1. *-commutativeN/A

            \[\leadsto \color{blue}{\log t \cdot a} \]
          2. lower-*.f64N/A

            \[\leadsto \color{blue}{\log t \cdot a} \]
          3. lower-log.f6497.8

            \[\leadsto \color{blue}{\log t} \cdot a \]
        5. Applied rewrites97.8%

          \[\leadsto \color{blue}{\log t \cdot a} \]
      10. Recombined 4 regimes into one program.
      11. Final simplification88.1%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq -4000000000000:\\ \;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\ \mathbf{elif}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq 500:\\ \;\;\;\;\mathsf{fma}\left(\log t, -0.5 + a, \log \left(z \cdot y\right)\right) - t\\ \mathbf{elif}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq 2000:\\ \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log z + \log \left(y + x\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \]
      12. Add Preprocessing

      Alternative 3: 63.4% accurate, 0.7× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq 710:\\ \;\;\;\;\mathsf{fma}\left(\log t, -0.5 + a, \log \left(z \cdot y\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\ \end{array} \end{array} \]
      (FPCore (x y z t a)
       :precision binary64
       (if (<= (+ (log (+ x y)) (log z)) 710.0)
         (- (fma (log t) (+ -0.5 a) (log (* z y))) t)
         (fma (* a (/ (log t) t)) t (- t))))
      double code(double x, double y, double z, double t, double a) {
      	double tmp;
      	if ((log((x + y)) + log(z)) <= 710.0) {
      		tmp = fma(log(t), (-0.5 + a), log((z * y))) - t;
      	} else {
      		tmp = fma((a * (log(t) / t)), t, -t);
      	}
      	return tmp;
      }
      
      function code(x, y, z, t, a)
      	tmp = 0.0
      	if (Float64(log(Float64(x + y)) + log(z)) <= 710.0)
      		tmp = Float64(fma(log(t), Float64(-0.5 + a), log(Float64(z * y))) - t);
      	else
      		tmp = fma(Float64(a * Float64(log(t) / t)), t, Float64(-t));
      	end
      	return tmp
      end
      
      code[x_, y_, z_, t_, a_] := If[LessEqual[N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision], 710.0], N[(N[(N[Log[t], $MachinePrecision] * N[(-0.5 + a), $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(a * N[(N[Log[t], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision] * t + (-t)), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\log \left(x + y\right) + \log z \leq 710:\\
      \;\;\;\;\mathsf{fma}\left(\log t, -0.5 + a, \log \left(z \cdot y\right)\right) - t\\
      
      \mathbf{else}:\\
      \;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 710

        1. Initial program 99.6%

          \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. lift-+.f64N/A

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

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

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

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

            \[\leadsto \frac{1}{\color{blue}{\frac{1}{\frac{\left(\left(\log \left(x + y\right) + \log z\right) - t\right) \cdot \left(\left(\log \left(x + y\right) + \log z\right) - t\right) - \left(\left(a - \frac{1}{2}\right) \cdot \log t\right) \cdot \left(\left(a - \frac{1}{2}\right) \cdot \log t\right)}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right) - \left(a - \frac{1}{2}\right) \cdot \log t}}}} \]
        4. Applied rewrites95.9%

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

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

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

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

            \[\leadsto \left(\log t \cdot \color{blue}{\left(a + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)} + \log \left(y \cdot z\right)\right) - t \]
          4. metadata-evalN/A

            \[\leadsto \left(\log t \cdot \left(a + \color{blue}{\frac{-1}{2}}\right) + \log \left(y \cdot z\right)\right) - t \]
          5. distribute-rgt-inN/A

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

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

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

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

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

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

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

            \[\leadsto \mathsf{fma}\left(\log t, \frac{-1}{2} + a, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
          13. lower-*.f6460.0

            \[\leadsto \mathsf{fma}\left(\log t, -0.5 + a, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
        7. Applied rewrites60.0%

          \[\leadsto \color{blue}{\mathsf{fma}\left(\log t, -0.5 + a, \log \left(z \cdot y\right)\right) - t} \]

        if 710 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

        1. Initial program 99.8%

          \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
        2. Add Preprocessing
        3. Taylor expanded in t around inf

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

            \[\leadsto t \cdot \color{blue}{\left(\left(-1 \cdot \frac{\log \left(\frac{1}{t}\right) \cdot \left(a - \frac{1}{2}\right)}{t} + \left(\frac{\log z}{t} + \frac{\log \left(x + y\right)}{t}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)\right)} \]
          2. metadata-evalN/A

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

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

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

            \[\leadsto \color{blue}{\mathsf{fma}\left(-1 \cdot \frac{\log \left(\frac{1}{t}\right) \cdot \left(a - \frac{1}{2}\right)}{t} + \left(\frac{\log z}{t} + \frac{\log \left(x + y\right)}{t}\right), t, \mathsf{neg}\left(t\right)\right)} \]
        5. Applied rewrites87.8%

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

          \[\leadsto \mathsf{fma}\left(\frac{a \cdot \log t}{t}, t, -t\right) \]
        7. Step-by-step derivation
          1. Applied rewrites72.5%

            \[\leadsto \mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right) \]
        8. Recombined 2 regimes into one program.
        9. Add Preprocessing

        Alternative 4: 98.5% accurate, 1.0× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 520:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(y + x\right)\right) + \log z\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\ \end{array} \end{array} \]
        (FPCore (x y z t a)
         :precision binary64
         (if (<= t 520.0)
           (+ (fma (- a 0.5) (log t) (log (+ y x))) (log z))
           (fma (* a (/ (log t) t)) t (- t))))
        double code(double x, double y, double z, double t, double a) {
        	double tmp;
        	if (t <= 520.0) {
        		tmp = fma((a - 0.5), log(t), log((y + x))) + log(z);
        	} else {
        		tmp = fma((a * (log(t) / t)), t, -t);
        	}
        	return tmp;
        }
        
        function code(x, y, z, t, a)
        	tmp = 0.0
        	if (t <= 520.0)
        		tmp = Float64(fma(Float64(a - 0.5), log(t), log(Float64(y + x))) + log(z));
        	else
        		tmp = fma(Float64(a * Float64(log(t) / t)), t, Float64(-t));
        	end
        	return tmp
        end
        
        code[x_, y_, z_, t_, a_] := If[LessEqual[t, 520.0], N[(N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[N[(y + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision], N[(N[(a * N[(N[Log[t], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision] * t + (-t)), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;t \leq 520:\\
        \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(y + x\right)\right) + \log z\\
        
        \mathbf{else}:\\
        \;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if t < 520

          1. Initial program 99.3%

            \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
          2. Add Preprocessing
          3. Taylor expanded in t around 0

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

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

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

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

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

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

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

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

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

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

              \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \color{blue}{\left(y + x\right)}\right) + \log z \]
            11. lower-log.f6498.1

              \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \left(y + x\right)\right) + \color{blue}{\log z} \]
          5. Applied rewrites98.1%

            \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log \left(y + x\right)\right) + \log z} \]

          if 520 < t

          1. Initial program 99.9%

            \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
          2. Add Preprocessing
          3. Taylor expanded in t around inf

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

              \[\leadsto t \cdot \color{blue}{\left(\left(-1 \cdot \frac{\log \left(\frac{1}{t}\right) \cdot \left(a - \frac{1}{2}\right)}{t} + \left(\frac{\log z}{t} + \frac{\log \left(x + y\right)}{t}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)\right)} \]
            2. metadata-evalN/A

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

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

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

              \[\leadsto \color{blue}{\mathsf{fma}\left(-1 \cdot \frac{\log \left(\frac{1}{t}\right) \cdot \left(a - \frac{1}{2}\right)}{t} + \left(\frac{\log z}{t} + \frac{\log \left(x + y\right)}{t}\right), t, \mathsf{neg}\left(t\right)\right)} \]
          5. Applied rewrites99.8%

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

            \[\leadsto \mathsf{fma}\left(\frac{a \cdot \log t}{t}, t, -t\right) \]
          7. Step-by-step derivation
            1. Applied rewrites98.8%

              \[\leadsto \mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right) \]
          8. Recombined 2 regimes into one program.
          9. Add Preprocessing

          Alternative 5: 80.8% accurate, 1.0× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 520:\\ \;\;\;\;\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \log y\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\ \end{array} \end{array} \]
          (FPCore (x y z t a)
           :precision binary64
           (if (<= t 520.0)
             (+ (fma (+ -0.5 a) (log t) (log z)) (log y))
             (fma (* a (/ (log t) t)) t (- t))))
          double code(double x, double y, double z, double t, double a) {
          	double tmp;
          	if (t <= 520.0) {
          		tmp = fma((-0.5 + a), log(t), log(z)) + log(y);
          	} else {
          		tmp = fma((a * (log(t) / t)), t, -t);
          	}
          	return tmp;
          }
          
          function code(x, y, z, t, a)
          	tmp = 0.0
          	if (t <= 520.0)
          		tmp = Float64(fma(Float64(-0.5 + a), log(t), log(z)) + log(y));
          	else
          		tmp = fma(Float64(a * Float64(log(t) / t)), t, Float64(-t));
          	end
          	return tmp
          end
          
          code[x_, y_, z_, t_, a_] := If[LessEqual[t, 520.0], N[(N[(N[(-0.5 + a), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision], N[(N[(a * N[(N[Log[t], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision] * t + (-t)), $MachinePrecision]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;t \leq 520:\\
          \;\;\;\;\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \log y\\
          
          \mathbf{else}:\\
          \;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if t < 520

            1. Initial program 99.3%

              \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
            2. Add Preprocessing
            3. Step-by-step derivation
              1. lift-*.f64N/A

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

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

                \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\left(a - \frac{1}{2}\right)} \]
              4. flip3--N/A

                \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\frac{{a}^{3} - {\frac{1}{2}}^{3}}{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}} \]
              5. clear-numN/A

                \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \color{blue}{\frac{1}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
              6. un-div-invN/A

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

                \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}{{a}^{3} - {\frac{1}{2}}^{3}}}} \]
              8. clear-numN/A

                \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{\frac{{a}^{3} - {\frac{1}{2}}^{3}}{a \cdot a + \left(\frac{1}{2} \cdot \frac{1}{2} + a \cdot \frac{1}{2}\right)}}}} \]
              9. flip3--N/A

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

                \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\frac{1}{\color{blue}{a - \frac{1}{2}}}} \]
              11. lower-/.f6499.3

                \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
            4. Applied rewrites99.3%

              \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
            5. Taylor expanded in x around 0

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

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

                \[\leadsto \left(\left(\log z + \log t \cdot \left(a - \frac{1}{2}\right)\right) + \color{blue}{\left(\mathsf{neg}\left(\left(\mathsf{neg}\left(\log y\right)\right)\right)\right)}\right) - t \]
              3. log-recN/A

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

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

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

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

                \[\leadsto \color{blue}{\left(\log t \cdot \left(a - \frac{1}{2}\right) + \log z\right)} + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right) \]
              8. sub-negN/A

                \[\leadsto \left(\log t \cdot \color{blue}{\left(a + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)\right)} + \log z\right) + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right) \]
              9. metadata-evalN/A

                \[\leadsto \left(\log t \cdot \left(a + \color{blue}{\frac{-1}{2}}\right) + \log z\right) + \left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right) \]
              10. distribute-rgt-inN/A

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

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

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

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

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

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

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

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

                \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log z\right) + \color{blue}{\left(-1 \cdot \log \left(\frac{1}{y}\right) - t\right)} \]
            7. Applied rewrites55.9%

              \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
            8. Taylor expanded in t around 0

              \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log z\right) + \log y \]
            9. Step-by-step derivation
              1. Applied rewrites54.8%

                \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \log y \]

              if 520 < t

              1. Initial program 99.9%

                \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
              2. Add Preprocessing
              3. Taylor expanded in t around inf

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

                  \[\leadsto t \cdot \color{blue}{\left(\left(-1 \cdot \frac{\log \left(\frac{1}{t}\right) \cdot \left(a - \frac{1}{2}\right)}{t} + \left(\frac{\log z}{t} + \frac{\log \left(x + y\right)}{t}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)\right)} \]
                2. metadata-evalN/A

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

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

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

                  \[\leadsto \color{blue}{\mathsf{fma}\left(-1 \cdot \frac{\log \left(\frac{1}{t}\right) \cdot \left(a - \frac{1}{2}\right)}{t} + \left(\frac{\log z}{t} + \frac{\log \left(x + y\right)}{t}\right), t, \mathsf{neg}\left(t\right)\right)} \]
              5. Applied rewrites99.8%

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

                \[\leadsto \mathsf{fma}\left(\frac{a \cdot \log t}{t}, t, -t\right) \]
              7. Step-by-step derivation
                1. Applied rewrites98.8%

                  \[\leadsto \mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right) \]
              8. Recombined 2 regimes into one program.
              9. Final simplification79.2%

                \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 520:\\ \;\;\;\;\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \log y\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\ \end{array} \]
              10. Add Preprocessing

              Alternative 6: 69.3% accurate, 1.0× speedup?

              \[\begin{array}{l} \\ \mathsf{fma}\left(a - 0.5, \log t, \log z\right) - \left(t - \log y\right) \end{array} \]
              (FPCore (x y z t a)
               :precision binary64
               (- (fma (- a 0.5) (log t) (log z)) (- t (log y))))
              double code(double x, double y, double z, double t, double a) {
              	return fma((a - 0.5), log(t), log(z)) - (t - log(y));
              }
              
              function code(x, y, z, t, a)
              	return Float64(fma(Float64(a - 0.5), log(t), log(z)) - Float64(t - log(y)))
              end
              
              code[x_, y_, z_, t_, a_] := N[(N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - N[(t - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \mathsf{fma}\left(a - 0.5, \log t, \log z\right) - \left(t - \log y\right)
              \end{array}
              
              Derivation
              1. Initial program 99.7%

                \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
              2. Add Preprocessing
              3. Taylor expanded in x around 0

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

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

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

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

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

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

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

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

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

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

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

                  \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log z\right) - \color{blue}{\left(t - \log y\right)} \]
                12. lower-log.f6463.4

                  \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log z\right) - \left(t - \color{blue}{\log y}\right) \]
              5. Applied rewrites63.4%

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

              Alternative 7: 75.0% accurate, 2.5× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 1.25 \cdot 10^{-44}:\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\ \end{array} \end{array} \]
              (FPCore (x y z t a)
               :precision binary64
               (if (<= t 1.25e-44) (* (log t) a) (fma (* a (/ (log t) t)) t (- t))))
              double code(double x, double y, double z, double t, double a) {
              	double tmp;
              	if (t <= 1.25e-44) {
              		tmp = log(t) * a;
              	} else {
              		tmp = fma((a * (log(t) / t)), t, -t);
              	}
              	return tmp;
              }
              
              function code(x, y, z, t, a)
              	tmp = 0.0
              	if (t <= 1.25e-44)
              		tmp = Float64(log(t) * a);
              	else
              		tmp = fma(Float64(a * Float64(log(t) / t)), t, Float64(-t));
              	end
              	return tmp
              end
              
              code[x_, y_, z_, t_, a_] := If[LessEqual[t, 1.25e-44], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision], N[(N[(a * N[(N[Log[t], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision] * t + (-t)), $MachinePrecision]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;t \leq 1.25 \cdot 10^{-44}:\\
              \;\;\;\;\log t \cdot a\\
              
              \mathbf{else}:\\
              \;\;\;\;\mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right)\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if t < 1.2500000000000001e-44

                1. Initial program 99.3%

                  \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                2. Add Preprocessing
                3. Taylor expanded in a around inf

                  \[\leadsto \color{blue}{a \cdot \log t} \]
                4. Step-by-step derivation
                  1. *-commutativeN/A

                    \[\leadsto \color{blue}{\log t \cdot a} \]
                  2. lower-*.f64N/A

                    \[\leadsto \color{blue}{\log t \cdot a} \]
                  3. lower-log.f6447.9

                    \[\leadsto \color{blue}{\log t} \cdot a \]
                5. Applied rewrites47.9%

                  \[\leadsto \color{blue}{\log t \cdot a} \]

                if 1.2500000000000001e-44 < t

                1. Initial program 99.8%

                  \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                2. Add Preprocessing
                3. Taylor expanded in t around inf

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

                    \[\leadsto t \cdot \color{blue}{\left(\left(-1 \cdot \frac{\log \left(\frac{1}{t}\right) \cdot \left(a - \frac{1}{2}\right)}{t} + \left(\frac{\log z}{t} + \frac{\log \left(x + y\right)}{t}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)\right)} \]
                  2. metadata-evalN/A

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

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

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

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

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

                  \[\leadsto \mathsf{fma}\left(\frac{a \cdot \log t}{t}, t, -t\right) \]
                7. Step-by-step derivation
                  1. Applied rewrites94.0%

                    \[\leadsto \mathsf{fma}\left(a \cdot \frac{\log t}{t}, t, -t\right) \]
                8. Recombined 2 regimes into one program.
                9. Add Preprocessing

                Alternative 8: 62.8% accurate, 2.6× speedup?

                \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -2 \cdot 10^{+44} \lor \neg \left(a - 0.5 \leq 2 \cdot 10^{+57}\right):\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
                (FPCore (x y z t a)
                 :precision binary64
                 (if (or (<= (- a 0.5) -2e+44) (not (<= (- a 0.5) 2e+57)))
                   (* (log t) a)
                   (- t)))
                double code(double x, double y, double z, double t, double a) {
                	double tmp;
                	if (((a - 0.5) <= -2e+44) || !((a - 0.5) <= 2e+57)) {
                		tmp = log(t) * a;
                	} else {
                		tmp = -t;
                	}
                	return tmp;
                }
                
                real(8) function code(x, y, z, t, a)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    real(8), intent (in) :: z
                    real(8), intent (in) :: t
                    real(8), intent (in) :: a
                    real(8) :: tmp
                    if (((a - 0.5d0) <= (-2d+44)) .or. (.not. ((a - 0.5d0) <= 2d+57))) then
                        tmp = log(t) * a
                    else
                        tmp = -t
                    end if
                    code = tmp
                end function
                
                public static double code(double x, double y, double z, double t, double a) {
                	double tmp;
                	if (((a - 0.5) <= -2e+44) || !((a - 0.5) <= 2e+57)) {
                		tmp = Math.log(t) * a;
                	} else {
                		tmp = -t;
                	}
                	return tmp;
                }
                
                def code(x, y, z, t, a):
                	tmp = 0
                	if ((a - 0.5) <= -2e+44) or not ((a - 0.5) <= 2e+57):
                		tmp = math.log(t) * a
                	else:
                		tmp = -t
                	return tmp
                
                function code(x, y, z, t, a)
                	tmp = 0.0
                	if ((Float64(a - 0.5) <= -2e+44) || !(Float64(a - 0.5) <= 2e+57))
                		tmp = Float64(log(t) * a);
                	else
                		tmp = Float64(-t);
                	end
                	return tmp
                end
                
                function tmp_2 = code(x, y, z, t, a)
                	tmp = 0.0;
                	if (((a - 0.5) <= -2e+44) || ~(((a - 0.5) <= 2e+57)))
                		tmp = log(t) * a;
                	else
                		tmp = -t;
                	end
                	tmp_2 = tmp;
                end
                
                code[x_, y_, z_, t_, a_] := If[Or[LessEqual[N[(a - 0.5), $MachinePrecision], -2e+44], N[Not[LessEqual[N[(a - 0.5), $MachinePrecision], 2e+57]], $MachinePrecision]], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision], (-t)]
                
                \begin{array}{l}
                
                \\
                \begin{array}{l}
                \mathbf{if}\;a - 0.5 \leq -2 \cdot 10^{+44} \lor \neg \left(a - 0.5 \leq 2 \cdot 10^{+57}\right):\\
                \;\;\;\;\log t \cdot a\\
                
                \mathbf{else}:\\
                \;\;\;\;-t\\
                
                
                \end{array}
                \end{array}
                
                Derivation
                1. Split input into 2 regimes
                2. if (-.f64 a #s(literal 1/2 binary64)) < -2.0000000000000002e44 or 2.0000000000000001e57 < (-.f64 a #s(literal 1/2 binary64))

                  1. Initial program 99.7%

                    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                  2. Add Preprocessing
                  3. Taylor expanded in a around inf

                    \[\leadsto \color{blue}{a \cdot \log t} \]
                  4. Step-by-step derivation
                    1. *-commutativeN/A

                      \[\leadsto \color{blue}{\log t \cdot a} \]
                    2. lower-*.f64N/A

                      \[\leadsto \color{blue}{\log t \cdot a} \]
                    3. lower-log.f6483.1

                      \[\leadsto \color{blue}{\log t} \cdot a \]
                  5. Applied rewrites83.1%

                    \[\leadsto \color{blue}{\log t \cdot a} \]

                  if -2.0000000000000002e44 < (-.f64 a #s(literal 1/2 binary64)) < 2.0000000000000001e57

                  1. Initial program 99.6%

                    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                  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.f6455.7

                      \[\leadsto \color{blue}{-t} \]
                  5. Applied rewrites55.7%

                    \[\leadsto \color{blue}{-t} \]
                3. Recombined 2 regimes into one program.
                4. Final simplification67.4%

                  \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -2 \cdot 10^{+44} \lor \neg \left(a - 0.5 \leq 2 \cdot 10^{+57}\right):\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]
                5. Add Preprocessing

                Alternative 9: 38.4% accurate, 107.0× speedup?

                \[\begin{array}{l} \\ -t \end{array} \]
                (FPCore (x y z t a) :precision binary64 (- t))
                double code(double x, double y, double z, double t, double a) {
                	return -t;
                }
                
                real(8) function code(x, y, z, t, a)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    real(8), intent (in) :: z
                    real(8), intent (in) :: t
                    real(8), intent (in) :: a
                    code = -t
                end function
                
                public static double code(double x, double y, double z, double t, double a) {
                	return -t;
                }
                
                def code(x, y, z, t, a):
                	return -t
                
                function code(x, y, z, t, a)
                	return Float64(-t)
                end
                
                function tmp = code(x, y, z, t, a)
                	tmp = -t;
                end
                
                code[x_, y_, z_, t_, a_] := (-t)
                
                \begin{array}{l}
                
                \\
                -t
                \end{array}
                
                Derivation
                1. Initial program 99.7%

                  \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                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.f6439.3

                    \[\leadsto \color{blue}{-t} \]
                5. Applied rewrites39.3%

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

                Alternative 10: 2.4% accurate, 321.0× speedup?

                \[\begin{array}{l} \\ t \end{array} \]
                (FPCore (x y z t a) :precision binary64 t)
                double code(double x, double y, double z, double t, double a) {
                	return t;
                }
                
                real(8) function code(x, y, z, t, a)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    real(8), intent (in) :: z
                    real(8), intent (in) :: t
                    real(8), intent (in) :: a
                    code = t
                end function
                
                public static double code(double x, double y, double z, double t, double a) {
                	return t;
                }
                
                def code(x, y, z, t, a):
                	return t
                
                function code(x, y, z, t, a)
                	return t
                end
                
                function tmp = code(x, y, z, t, a)
                	tmp = t;
                end
                
                code[x_, y_, z_, t_, a_] := t
                
                \begin{array}{l}
                
                \\
                t
                \end{array}
                
                Derivation
                1. Initial program 99.7%

                  \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                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.f6439.3

                    \[\leadsto \color{blue}{-t} \]
                5. Applied rewrites39.3%

                  \[\leadsto \color{blue}{-t} \]
                6. Step-by-step derivation
                  1. Applied rewrites20.0%

                    \[\leadsto \frac{0 - t \cdot t}{\color{blue}{0 + t}} \]
                  2. Applied rewrites2.4%

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

                  Developer Target 1: 99.6% accurate, 1.0× speedup?

                  \[\begin{array}{l} \\ \log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right) \end{array} \]
                  (FPCore (x y z t a)
                   :precision binary64
                   (+ (log (+ x y)) (+ (- (log z) t) (* (- a 0.5) (log t)))))
                  double code(double x, double y, double z, double t, double a) {
                  	return log((x + y)) + ((log(z) - t) + ((a - 0.5) * log(t)));
                  }
                  
                  real(8) function code(x, y, z, t, a)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      real(8), intent (in) :: z
                      real(8), intent (in) :: t
                      real(8), intent (in) :: a
                      code = log((x + y)) + ((log(z) - t) + ((a - 0.5d0) * log(t)))
                  end function
                  
                  public static double code(double x, double y, double z, double t, double a) {
                  	return Math.log((x + y)) + ((Math.log(z) - t) + ((a - 0.5) * Math.log(t)));
                  }
                  
                  def code(x, y, z, t, a):
                  	return math.log((x + y)) + ((math.log(z) - t) + ((a - 0.5) * math.log(t)))
                  
                  function code(x, y, z, t, a)
                  	return Float64(log(Float64(x + y)) + Float64(Float64(log(z) - t) + Float64(Float64(a - 0.5) * log(t))))
                  end
                  
                  function tmp = code(x, y, z, t, a)
                  	tmp = log((x + y)) + ((log(z) - t) + ((a - 0.5) * log(t)));
                  end
                  
                  code[x_, y_, z_, t_, a_] := N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[(N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)
                  \end{array}
                  

                  Reproduce

                  ?
                  herbie shell --seed 2024313 
                  (FPCore (x y z t a)
                    :name "Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2"
                    :precision binary64
                  
                    :alt
                    (! :herbie-platform default (+ (log (+ x y)) (+ (- (log z) t) (* (- a 1/2) (log t)))))
                  
                    (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))