Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 15.7s
Alternatives: 13
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 13 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?

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

\\
\left(\left(\log z + \log \left(y + x\right)\right) - t\right) - \left(0.5 - a\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. Final simplification99.7%

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

Alternative 2: 89.2% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log t \cdot a\\ t_2 := \log z + \log \left(y + x\right)\\ \mathbf{if}\;t\_2 \leq -750:\\ \;\;\;\;\frac{1}{\frac{1}{\left(\log z - t\right) + t\_1}}\\ \mathbf{elif}\;t\_2 \leq 655:\\ \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(t\_1 + \log y\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (* (log t) a)) (t_2 (+ (log z) (log (+ y x)))))
   (if (<= t_2 -750.0)
     (/ 1.0 (/ 1.0 (+ (- (log z) t) t_1)))
     (if (<= t_2 655.0)
       (- (log (* z (+ y x))) (- t (* (log t) (- a 0.5))))
       (- (+ t_1 (log y)) t)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = log(t) * a;
	double t_2 = log(z) + log((y + x));
	double tmp;
	if (t_2 <= -750.0) {
		tmp = 1.0 / (1.0 / ((log(z) - t) + t_1));
	} else if (t_2 <= 655.0) {
		tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5)));
	} else {
		tmp = (t_1 + log(y)) - 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) :: t_1
    real(8) :: t_2
    real(8) :: tmp
    t_1 = log(t) * a
    t_2 = log(z) + log((y + x))
    if (t_2 <= (-750.0d0)) then
        tmp = 1.0d0 / (1.0d0 / ((log(z) - t) + t_1))
    else if (t_2 <= 655.0d0) then
        tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5d0)))
    else
        tmp = (t_1 + log(y)) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = Math.log(t) * a;
	double t_2 = Math.log(z) + Math.log((y + x));
	double tmp;
	if (t_2 <= -750.0) {
		tmp = 1.0 / (1.0 / ((Math.log(z) - t) + t_1));
	} else if (t_2 <= 655.0) {
		tmp = Math.log((z * (y + x))) - (t - (Math.log(t) * (a - 0.5)));
	} else {
		tmp = (t_1 + Math.log(y)) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = math.log(t) * a
	t_2 = math.log(z) + math.log((y + x))
	tmp = 0
	if t_2 <= -750.0:
		tmp = 1.0 / (1.0 / ((math.log(z) - t) + t_1))
	elif t_2 <= 655.0:
		tmp = math.log((z * (y + x))) - (t - (math.log(t) * (a - 0.5)))
	else:
		tmp = (t_1 + math.log(y)) - t
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(log(t) * a)
	t_2 = Float64(log(z) + log(Float64(y + x)))
	tmp = 0.0
	if (t_2 <= -750.0)
		tmp = Float64(1.0 / Float64(1.0 / Float64(Float64(log(z) - t) + t_1)));
	elseif (t_2 <= 655.0)
		tmp = Float64(log(Float64(z * Float64(y + x))) - Float64(t - Float64(log(t) * Float64(a - 0.5))));
	else
		tmp = Float64(Float64(t_1 + log(y)) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = log(t) * a;
	t_2 = log(z) + log((y + x));
	tmp = 0.0;
	if (t_2 <= -750.0)
		tmp = 1.0 / (1.0 / ((log(z) - t) + t_1));
	elseif (t_2 <= 655.0)
		tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5)));
	else
		tmp = (t_1 + log(y)) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision]}, Block[{t$95$2 = N[(N[Log[z], $MachinePrecision] + N[Log[N[(y + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$2, -750.0], N[(1.0 / N[(1.0 / N[(N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision] + t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$2, 655.0], N[(N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - N[(t - N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(t$95$1 + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \log t \cdot a\\
t_2 := \log z + \log \left(y + x\right)\\
\mathbf{if}\;t\_2 \leq -750:\\
\;\;\;\;\frac{1}{\frac{1}{\left(\log z - t\right) + t\_1}}\\

\mathbf{elif}\;t\_2 \leq 655:\\
\;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\left(t\_1 + \log y\right) - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750

    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

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - \frac{1}{2}\right) \cdot \log t} \]
      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 rewrites2.9%

      \[\leadsto \color{blue}{\frac{1}{\frac{1}{\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \left(y + x\right)\right) - t\right)}}} \]
    5. Step-by-step derivation
      1. lift-fma.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{\left(\log t \cdot \left(a - \frac{1}{2}\right) + \log \left(x + y\right)\right) + \left(\log z - t\right)}}} \]
    6. Applied rewrites99.9%

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

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

        \[\leadsto \frac{1}{\frac{1}{\color{blue}{a \cdot \log t} + \left(\log z - t\right)}} \]
      2. lower-log.f6486.1

        \[\leadsto \frac{1}{\frac{1}{a \cdot \color{blue}{\log t} + \left(\log z - t\right)}} \]
    9. Applied rewrites86.1%

      \[\leadsto \frac{1}{\frac{1}{\color{blue}{a \cdot \log t} + \left(\log z - t\right)}} \]

    if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 655

    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. lift--.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(z \cdot \left(y + x\right)\right) - \color{blue}{\left(t - \left(a - 0.5\right) \cdot \log t\right)} \]
      16. lift-*.f64N/A

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

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

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

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

    if 655 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

    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. 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-/.f6499.8

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
    4. Applied rewrites99.8%

      \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
    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. lower--.f64N/A

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

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

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

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

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

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

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

        \[\leadsto \left(\log y + \mathsf{fma}\left(a - \frac{1}{2}, \color{blue}{\log t}, \log z\right)\right) - t \]
      9. lower-log.f6462.9

        \[\leadsto \left(\log y + \mathsf{fma}\left(a - 0.5, \log t, \color{blue}{\log z}\right)\right) - t \]
    7. Applied rewrites62.9%

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

      \[\leadsto \left(\log y + a \cdot \log t\right) - t \]
    9. Step-by-step derivation
      1. Applied rewrites56.9%

        \[\leadsto \left(\log y + a \cdot \log t\right) - t \]
    10. Recombined 3 regimes into one program.
    11. Final simplification88.7%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\log z + \log \left(y + x\right) \leq -750:\\ \;\;\;\;\frac{1}{\frac{1}{\left(\log z - t\right) + \log t \cdot a}}\\ \mathbf{elif}\;\log z + \log \left(y + x\right) \leq 655:\\ \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \end{array} \]
    12. Add Preprocessing

    Alternative 3: 88.6% accurate, 0.5× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log z + \log \left(y + x\right)\\ t_2 := \left(\log t \cdot a + \log y\right) - t\\ \mathbf{if}\;t\_1 \leq -750:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;t\_1 \leq 655:\\ \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;t\_2\\ \end{array} \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (let* ((t_1 (+ (log z) (log (+ y x)))) (t_2 (- (+ (* (log t) a) (log y)) t)))
       (if (<= t_1 -750.0)
         t_2
         (if (<= t_1 655.0)
           (- (log (* z (+ y x))) (- t (* (log t) (- a 0.5))))
           t_2))))
    double code(double x, double y, double z, double t, double a) {
    	double t_1 = log(z) + log((y + x));
    	double t_2 = ((log(t) * a) + log(y)) - t;
    	double tmp;
    	if (t_1 <= -750.0) {
    		tmp = t_2;
    	} else if (t_1 <= 655.0) {
    		tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5)));
    	} else {
    		tmp = t_2;
    	}
    	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) :: t_1
        real(8) :: t_2
        real(8) :: tmp
        t_1 = log(z) + log((y + x))
        t_2 = ((log(t) * a) + log(y)) - t
        if (t_1 <= (-750.0d0)) then
            tmp = t_2
        else if (t_1 <= 655.0d0) then
            tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5d0)))
        else
            tmp = t_2
        end if
        code = tmp
    end function
    
    public static double code(double x, double y, double z, double t, double a) {
    	double t_1 = Math.log(z) + Math.log((y + x));
    	double t_2 = ((Math.log(t) * a) + Math.log(y)) - t;
    	double tmp;
    	if (t_1 <= -750.0) {
    		tmp = t_2;
    	} else if (t_1 <= 655.0) {
    		tmp = Math.log((z * (y + x))) - (t - (Math.log(t) * (a - 0.5)));
    	} else {
    		tmp = t_2;
    	}
    	return tmp;
    }
    
    def code(x, y, z, t, a):
    	t_1 = math.log(z) + math.log((y + x))
    	t_2 = ((math.log(t) * a) + math.log(y)) - t
    	tmp = 0
    	if t_1 <= -750.0:
    		tmp = t_2
    	elif t_1 <= 655.0:
    		tmp = math.log((z * (y + x))) - (t - (math.log(t) * (a - 0.5)))
    	else:
    		tmp = t_2
    	return tmp
    
    function code(x, y, z, t, a)
    	t_1 = Float64(log(z) + log(Float64(y + x)))
    	t_2 = Float64(Float64(Float64(log(t) * a) + log(y)) - t)
    	tmp = 0.0
    	if (t_1 <= -750.0)
    		tmp = t_2;
    	elseif (t_1 <= 655.0)
    		tmp = Float64(log(Float64(z * Float64(y + x))) - Float64(t - Float64(log(t) * Float64(a - 0.5))));
    	else
    		tmp = t_2;
    	end
    	return tmp
    end
    
    function tmp_2 = code(x, y, z, t, a)
    	t_1 = log(z) + log((y + x));
    	t_2 = ((log(t) * a) + log(y)) - t;
    	tmp = 0.0;
    	if (t_1 <= -750.0)
    		tmp = t_2;
    	elseif (t_1 <= 655.0)
    		tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5)));
    	else
    		tmp = t_2;
    	end
    	tmp_2 = tmp;
    end
    
    code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[z], $MachinePrecision] + N[Log[N[(y + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]}, If[LessEqual[t$95$1, -750.0], t$95$2, If[LessEqual[t$95$1, 655.0], N[(N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - N[(t - N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], t$95$2]]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_1 := \log z + \log \left(y + x\right)\\
    t_2 := \left(\log t \cdot a + \log y\right) - t\\
    \mathbf{if}\;t\_1 \leq -750:\\
    \;\;\;\;t\_2\\
    
    \mathbf{elif}\;t\_1 \leq 655:\\
    \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;t\_2\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750 or 655 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

      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. 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-/.f6499.8

          \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
      4. Applied rewrites99.8%

        \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
      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. lower--.f64N/A

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

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

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

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

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

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

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

          \[\leadsto \left(\log y + \mathsf{fma}\left(a - \frac{1}{2}, \color{blue}{\log t}, \log z\right)\right) - t \]
        9. lower-log.f6463.0

          \[\leadsto \left(\log y + \mathsf{fma}\left(a - 0.5, \log t, \color{blue}{\log z}\right)\right) - t \]
      7. Applied rewrites63.0%

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

        \[\leadsto \left(\log y + a \cdot \log t\right) - t \]
      9. Step-by-step derivation
        1. Applied rewrites56.8%

          \[\leadsto \left(\log y + a \cdot \log t\right) - t \]

        if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 655

        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. lift--.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \log \left(z \cdot \left(y + x\right)\right) - \color{blue}{\left(t - \left(a - 0.5\right) \cdot \log t\right)} \]
          16. lift-*.f64N/A

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

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

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

          \[\leadsto \color{blue}{\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)} \]
      10. Recombined 2 regimes into one program.
      11. Final simplification87.4%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\log z + \log \left(y + x\right) \leq -750:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \mathbf{elif}\;\log z + \log \left(y + x\right) \leq 655:\\ \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \end{array} \]
      12. Add Preprocessing

      Alternative 4: 88.6% accurate, 0.5× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log z + \log \left(y + x\right)\\ t_2 := \left(\log t \cdot a + \log y\right) - t\\ \mathbf{if}\;t\_1 \leq -750:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;t\_1 \leq 655:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)\\ \mathbf{else}:\\ \;\;\;\;t\_2\\ \end{array} \end{array} \]
      (FPCore (x y z t a)
       :precision binary64
       (let* ((t_1 (+ (log z) (log (+ y x)))) (t_2 (- (+ (* (log t) a) (log y)) t)))
         (if (<= t_1 -750.0)
           t_2
           (if (<= t_1 655.0)
             (fma (- a 0.5) (log t) (- (log (* z (+ y x))) t))
             t_2))))
      double code(double x, double y, double z, double t, double a) {
      	double t_1 = log(z) + log((y + x));
      	double t_2 = ((log(t) * a) + log(y)) - t;
      	double tmp;
      	if (t_1 <= -750.0) {
      		tmp = t_2;
      	} else if (t_1 <= 655.0) {
      		tmp = fma((a - 0.5), log(t), (log((z * (y + x))) - t));
      	} else {
      		tmp = t_2;
      	}
      	return tmp;
      }
      
      function code(x, y, z, t, a)
      	t_1 = Float64(log(z) + log(Float64(y + x)))
      	t_2 = Float64(Float64(Float64(log(t) * a) + log(y)) - t)
      	tmp = 0.0
      	if (t_1 <= -750.0)
      		tmp = t_2;
      	elseif (t_1 <= 655.0)
      		tmp = fma(Float64(a - 0.5), log(t), Float64(log(Float64(z * Float64(y + x))) - t));
      	else
      		tmp = t_2;
      	end
      	return tmp
      end
      
      code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[z], $MachinePrecision] + N[Log[N[(y + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]}, If[LessEqual[t$95$1, -750.0], t$95$2, If[LessEqual[t$95$1, 655.0], N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[(N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision], t$95$2]]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_1 := \log z + \log \left(y + x\right)\\
      t_2 := \left(\log t \cdot a + \log y\right) - t\\
      \mathbf{if}\;t\_1 \leq -750:\\
      \;\;\;\;t\_2\\
      
      \mathbf{elif}\;t\_1 \leq 655:\\
      \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;t\_2\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750 or 655 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

        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. 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-/.f6499.8

            \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
        4. Applied rewrites99.8%

          \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
        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. lower--.f64N/A

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

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

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

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

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

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

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

            \[\leadsto \left(\log y + \mathsf{fma}\left(a - \frac{1}{2}, \color{blue}{\log t}, \log z\right)\right) - t \]
          9. lower-log.f6463.0

            \[\leadsto \left(\log y + \mathsf{fma}\left(a - 0.5, \log t, \color{blue}{\log z}\right)\right) - t \]
        7. Applied rewrites63.0%

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

          \[\leadsto \left(\log y + a \cdot \log t\right) - t \]
        9. Step-by-step derivation
          1. Applied rewrites56.8%

            \[\leadsto \left(\log y + a \cdot \log t\right) - t \]

          if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 655

          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. +-commutativeN/A

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

              \[\leadsto \color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} + \left(\left(\log \left(x + y\right) + \log z\right) - t\right) \]
            4. lower-fma.f6499.6

              \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \left(\log \left(x + y\right) + \log z\right) - t\right)} \]
            5. lift-+.f64N/A

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

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

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

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

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

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

              \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \color{blue}{\left(z \cdot \left(x + y\right)\right)} - t\right) \]
            12. lift-+.f64N/A

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

              \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - t\right) \]
            14. lower-+.f6499.7

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

            \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)} \]
        10. Recombined 2 regimes into one program.
        11. Final simplification87.4%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\log z + \log \left(y + x\right) \leq -750:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \mathbf{elif}\;\log z + \log \left(y + x\right) \leq 655:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \end{array} \]
        12. Add Preprocessing

        Alternative 5: 64.4% accurate, 0.5× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log z + \log \left(y + x\right)\\ t_2 := \left(\log t \cdot a + \log y\right) - t\\ \mathbf{if}\;t\_1 \leq -750:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;t\_1 \leq 655:\\ \;\;\;\;\log \left(z \cdot y\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;t\_2\\ \end{array} \end{array} \]
        (FPCore (x y z t a)
         :precision binary64
         (let* ((t_1 (+ (log z) (log (+ y x)))) (t_2 (- (+ (* (log t) a) (log y)) t)))
           (if (<= t_1 -750.0)
             t_2
             (if (<= t_1 655.0) (- (log (* z y)) (- t (* (log t) (- a 0.5)))) t_2))))
        double code(double x, double y, double z, double t, double a) {
        	double t_1 = log(z) + log((y + x));
        	double t_2 = ((log(t) * a) + log(y)) - t;
        	double tmp;
        	if (t_1 <= -750.0) {
        		tmp = t_2;
        	} else if (t_1 <= 655.0) {
        		tmp = log((z * y)) - (t - (log(t) * (a - 0.5)));
        	} else {
        		tmp = t_2;
        	}
        	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) :: t_1
            real(8) :: t_2
            real(8) :: tmp
            t_1 = log(z) + log((y + x))
            t_2 = ((log(t) * a) + log(y)) - t
            if (t_1 <= (-750.0d0)) then
                tmp = t_2
            else if (t_1 <= 655.0d0) then
                tmp = log((z * y)) - (t - (log(t) * (a - 0.5d0)))
            else
                tmp = t_2
            end if
            code = tmp
        end function
        
        public static double code(double x, double y, double z, double t, double a) {
        	double t_1 = Math.log(z) + Math.log((y + x));
        	double t_2 = ((Math.log(t) * a) + Math.log(y)) - t;
        	double tmp;
        	if (t_1 <= -750.0) {
        		tmp = t_2;
        	} else if (t_1 <= 655.0) {
        		tmp = Math.log((z * y)) - (t - (Math.log(t) * (a - 0.5)));
        	} else {
        		tmp = t_2;
        	}
        	return tmp;
        }
        
        def code(x, y, z, t, a):
        	t_1 = math.log(z) + math.log((y + x))
        	t_2 = ((math.log(t) * a) + math.log(y)) - t
        	tmp = 0
        	if t_1 <= -750.0:
        		tmp = t_2
        	elif t_1 <= 655.0:
        		tmp = math.log((z * y)) - (t - (math.log(t) * (a - 0.5)))
        	else:
        		tmp = t_2
        	return tmp
        
        function code(x, y, z, t, a)
        	t_1 = Float64(log(z) + log(Float64(y + x)))
        	t_2 = Float64(Float64(Float64(log(t) * a) + log(y)) - t)
        	tmp = 0.0
        	if (t_1 <= -750.0)
        		tmp = t_2;
        	elseif (t_1 <= 655.0)
        		tmp = Float64(log(Float64(z * y)) - Float64(t - Float64(log(t) * Float64(a - 0.5))));
        	else
        		tmp = t_2;
        	end
        	return tmp
        end
        
        function tmp_2 = code(x, y, z, t, a)
        	t_1 = log(z) + log((y + x));
        	t_2 = ((log(t) * a) + log(y)) - t;
        	tmp = 0.0;
        	if (t_1 <= -750.0)
        		tmp = t_2;
        	elseif (t_1 <= 655.0)
        		tmp = log((z * y)) - (t - (log(t) * (a - 0.5)));
        	else
        		tmp = t_2;
        	end
        	tmp_2 = tmp;
        end
        
        code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[z], $MachinePrecision] + N[Log[N[(y + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]}, If[LessEqual[t$95$1, -750.0], t$95$2, If[LessEqual[t$95$1, 655.0], N[(N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision] - N[(t - N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], t$95$2]]]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        t_1 := \log z + \log \left(y + x\right)\\
        t_2 := \left(\log t \cdot a + \log y\right) - t\\
        \mathbf{if}\;t\_1 \leq -750:\\
        \;\;\;\;t\_2\\
        
        \mathbf{elif}\;t\_1 \leq 655:\\
        \;\;\;\;\log \left(z \cdot y\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;t\_2\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750 or 655 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

          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. 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-/.f6499.8

              \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
          4. Applied rewrites99.8%

            \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
          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. lower--.f64N/A

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

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

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

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

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

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

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

              \[\leadsto \left(\log y + \mathsf{fma}\left(a - \frac{1}{2}, \color{blue}{\log t}, \log z\right)\right) - t \]
            9. lower-log.f6463.0

              \[\leadsto \left(\log y + \mathsf{fma}\left(a - 0.5, \log t, \color{blue}{\log z}\right)\right) - t \]
          7. Applied rewrites63.0%

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

            \[\leadsto \left(\log y + a \cdot \log t\right) - t \]
          9. Step-by-step derivation
            1. Applied rewrites56.8%

              \[\leadsto \left(\log y + a \cdot \log t\right) - t \]

            if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 655

            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 rewrites99.5%

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

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

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

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

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

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

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

                \[\leadsto \frac{1}{\frac{1}{\mathsf{fma}\left(\log t, a - \frac{1}{2}, \left(\log z - \color{blue}{\left(\mathsf{neg}\left(\log y\right)\right)}\right) - t\right)}} \]
              7. lower-log.f6468.7

                \[\leadsto \frac{1}{\frac{1}{\mathsf{fma}\left(\log t, a - 0.5, \left(\log z - \left(-\color{blue}{\log y}\right)\right) - t\right)}} \]
            7. Applied rewrites68.7%

              \[\leadsto \frac{1}{\frac{1}{\mathsf{fma}\left(\log t, a - 0.5, \color{blue}{\left(\log z - \left(-\log y\right)\right)} - t\right)}} \]
            8. Step-by-step derivation
              1. lift-/.f64N/A

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

                \[\leadsto \frac{1}{\color{blue}{\frac{1}{\mathsf{fma}\left(\log t, a - \frac{1}{2}, \left(\log z - \left(\mathsf{neg}\left(\log y\right)\right)\right) - t\right)}}} \]
              3. remove-double-div68.8

                \[\leadsto \color{blue}{\mathsf{fma}\left(\log t, a - 0.5, \left(\log z - \left(-\log y\right)\right) - t\right)} \]
              4. lift-fma.f64N/A

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

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

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

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

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

                \[\leadsto \color{blue}{\left(\log z - \left(\mathsf{neg}\left(\log y\right)\right)\right) - \left(t - \left(a - \frac{1}{2}\right) \cdot \log t\right)} \]
            9. Applied rewrites67.0%

              \[\leadsto \color{blue}{\log \left(z \cdot y\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)} \]
          10. Recombined 2 regimes into one program.
          11. Final simplification64.1%

            \[\leadsto \begin{array}{l} \mathbf{if}\;\log z + \log \left(y + x\right) \leq -750:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \mathbf{elif}\;\log z + \log \left(y + x\right) \leq 655:\\ \;\;\;\;\log \left(z \cdot y\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \end{array} \]
          12. Add Preprocessing

          Alternative 6: 64.4% accurate, 0.5× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log z + \log \left(y + x\right)\\ t_2 := \left(\log t \cdot a + \log y\right) - t\\ \mathbf{if}\;t\_1 \leq -750:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;t\_1 \leq 655:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot y\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;t\_2\\ \end{array} \end{array} \]
          (FPCore (x y z t a)
           :precision binary64
           (let* ((t_1 (+ (log z) (log (+ y x)))) (t_2 (- (+ (* (log t) a) (log y)) t)))
             (if (<= t_1 -750.0)
               t_2
               (if (<= t_1 655.0) (- (fma (- a 0.5) (log t) (log (* z y))) t) t_2))))
          double code(double x, double y, double z, double t, double a) {
          	double t_1 = log(z) + log((y + x));
          	double t_2 = ((log(t) * a) + log(y)) - t;
          	double tmp;
          	if (t_1 <= -750.0) {
          		tmp = t_2;
          	} else if (t_1 <= 655.0) {
          		tmp = fma((a - 0.5), log(t), log((z * y))) - t;
          	} else {
          		tmp = t_2;
          	}
          	return tmp;
          }
          
          function code(x, y, z, t, a)
          	t_1 = Float64(log(z) + log(Float64(y + x)))
          	t_2 = Float64(Float64(Float64(log(t) * a) + log(y)) - t)
          	tmp = 0.0
          	if (t_1 <= -750.0)
          		tmp = t_2;
          	elseif (t_1 <= 655.0)
          		tmp = Float64(fma(Float64(a - 0.5), log(t), log(Float64(z * y))) - t);
          	else
          		tmp = t_2;
          	end
          	return tmp
          end
          
          code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[z], $MachinePrecision] + N[Log[N[(y + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]}, If[LessEqual[t$95$1, -750.0], t$95$2, If[LessEqual[t$95$1, 655.0], N[(N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], t$95$2]]]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          t_1 := \log z + \log \left(y + x\right)\\
          t_2 := \left(\log t \cdot a + \log y\right) - t\\
          \mathbf{if}\;t\_1 \leq -750:\\
          \;\;\;\;t\_2\\
          
          \mathbf{elif}\;t\_1 \leq 655:\\
          \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot y\right)\right) - t\\
          
          \mathbf{else}:\\
          \;\;\;\;t\_2\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750 or 655 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

            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. 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-/.f6499.8

                \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
            4. Applied rewrites99.8%

              \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
            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. lower--.f64N/A

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

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

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

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

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

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

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

                \[\leadsto \left(\log y + \mathsf{fma}\left(a - \frac{1}{2}, \color{blue}{\log t}, \log z\right)\right) - t \]
              9. lower-log.f6463.0

                \[\leadsto \left(\log y + \mathsf{fma}\left(a - 0.5, \log t, \color{blue}{\log z}\right)\right) - t \]
            7. Applied rewrites63.0%

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

              \[\leadsto \left(\log y + a \cdot \log t\right) - t \]
            9. Step-by-step derivation
              1. Applied rewrites56.8%

                \[\leadsto \left(\log y + a \cdot \log t\right) - t \]

              if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 655

              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 rewrites99.5%

                \[\leadsto \color{blue}{\frac{1}{\frac{1}{\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \left(y + x\right)\right) - t\right)}}} \]
              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. *-commutativeN/A

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

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

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

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

                  \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \color{blue}{\log \left(y \cdot z\right)}\right) - t \]
                8. lower-*.f6467.0

                  \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \color{blue}{\left(y \cdot z\right)}\right) - t \]
              7. Applied rewrites67.0%

                \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log \left(y \cdot z\right)\right) - t} \]
            10. Recombined 2 regimes into one program.
            11. Final simplification64.1%

              \[\leadsto \begin{array}{l} \mathbf{if}\;\log z + \log \left(y + x\right) \leq -750:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \mathbf{elif}\;\log z + \log \left(y + x\right) \leq 655:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot y\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \end{array} \]
            12. Add Preprocessing

            Alternative 7: 69.5% accurate, 1.0× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 520:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log z\right) + \log y\\ \mathbf{else}:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \end{array} \end{array} \]
            (FPCore (x y z t a)
             :precision binary64
             (if (<= t 520.0)
               (+ (fma (- a 0.5) (log t) (log z)) (log y))
               (- (+ (* (log t) a) (log y)) 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(z)) + log(y);
            	} else {
            		tmp = ((log(t) * a) + log(y)) - 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(z)) + log(y));
            	else
            		tmp = Float64(Float64(Float64(log(t) * a) + log(y)) - 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[z], $MachinePrecision]), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;t \leq 520:\\
            \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log z\right) + \log y\\
            
            \mathbf{else}:\\
            \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\
            
            
            \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. lower--.f64N/A

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

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

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

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

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

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

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

                  \[\leadsto \left(\log y + \mathsf{fma}\left(a - \frac{1}{2}, \color{blue}{\log t}, \log z\right)\right) - t \]
                9. lower-log.f6461.5

                  \[\leadsto \left(\log y + \mathsf{fma}\left(a - 0.5, \log t, \color{blue}{\log z}\right)\right) - t \]
              7. Applied rewrites61.5%

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

                \[\leadsto \log y + \color{blue}{\left(\log z + \log t \cdot \left(a - \frac{1}{2}\right)\right)} \]
              9. Step-by-step derivation
                1. Applied rewrites61.3%

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

                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. 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-/.f6499.9

                    \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
                4. Applied rewrites99.9%

                  \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
                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. lower--.f64N/A

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

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

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

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

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

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

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

                    \[\leadsto \left(\log y + \mathsf{fma}\left(a - \frac{1}{2}, \color{blue}{\log t}, \log z\right)\right) - t \]
                  9. lower-log.f6472.2

                    \[\leadsto \left(\log y + \mathsf{fma}\left(a - 0.5, \log t, \color{blue}{\log z}\right)\right) - t \]
                7. Applied rewrites72.2%

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

                  \[\leadsto \left(\log y + a \cdot \log t\right) - t \]
                9. Step-by-step derivation
                  1. Applied rewrites72.0%

                    \[\leadsto \left(\log y + a \cdot \log t\right) - t \]
                10. Recombined 2 regimes into one program.
                11. Final simplification67.0%

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

                Alternative 8: 70.0% accurate, 1.0× speedup?

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - \frac{1}{2}\right)\right)\right) - t} \]
                5. Applied rewrites67.1%

                  \[\leadsto \color{blue}{\left(\log y + \mathsf{fma}\left(a - 0.5, \log t, \log z\right)\right) - t} \]
                6. Final simplification67.1%

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

                Alternative 9: 58.0% accurate, 1.5× speedup?

                \[\begin{array}{l} \\ \left(\log t \cdot a + \log y\right) - t \end{array} \]
                (FPCore (x y z t a) :precision binary64 (- (+ (* (log t) a) (log y)) t))
                double code(double x, double y, double z, double t, double a) {
                	return ((log(t) * a) + log(y)) - 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(t) * a) + log(y)) - t
                end function
                
                public static double code(double x, double y, double z, double t, double a) {
                	return ((Math.log(t) * a) + Math.log(y)) - t;
                }
                
                def code(x, y, z, t, a):
                	return ((math.log(t) * a) + math.log(y)) - t
                
                function code(x, y, z, t, a)
                	return Float64(Float64(Float64(log(t) * a) + log(y)) - t)
                end
                
                function tmp = code(x, y, z, t, a)
                	tmp = ((log(t) * a) + log(y)) - t;
                end
                
                code[x_, y_, z_, t_, a_] := N[(N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \left(\log t \cdot a + \log y\right) - 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. 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-/.f6499.6

                    \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
                4. Applied rewrites99.6%

                  \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
                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. lower--.f64N/A

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

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

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

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

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

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

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

                    \[\leadsto \left(\log y + \mathsf{fma}\left(a - \frac{1}{2}, \color{blue}{\log t}, \log z\right)\right) - t \]
                  9. lower-log.f6467.1

                    \[\leadsto \left(\log y + \mathsf{fma}\left(a - 0.5, \log t, \color{blue}{\log z}\right)\right) - t \]
                7. Applied rewrites67.1%

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

                  \[\leadsto \left(\log y + a \cdot \log t\right) - t \]
                9. Step-by-step derivation
                  1. Applied rewrites57.1%

                    \[\leadsto \left(\log y + a \cdot \log t\right) - t \]
                  2. Final simplification57.1%

                    \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
                  3. Add Preprocessing

                  Alternative 10: 61.7% accurate, 2.6× speedup?

                  \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log t \cdot a\\ \mathbf{if}\;a - 0.5 \leq -2 \cdot 10^{+23}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;a - 0.5 \leq 10^{+55}:\\ \;\;\;\;-t\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \end{array} \]
                  (FPCore (x y z t a)
                   :precision binary64
                   (let* ((t_1 (* (log t) a)))
                     (if (<= (- a 0.5) -2e+23) t_1 (if (<= (- a 0.5) 1e+55) (- t) t_1))))
                  double code(double x, double y, double z, double t, double a) {
                  	double t_1 = log(t) * a;
                  	double tmp;
                  	if ((a - 0.5) <= -2e+23) {
                  		tmp = t_1;
                  	} else if ((a - 0.5) <= 1e+55) {
                  		tmp = -t;
                  	} else {
                  		tmp = t_1;
                  	}
                  	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) :: t_1
                      real(8) :: tmp
                      t_1 = log(t) * a
                      if ((a - 0.5d0) <= (-2d+23)) then
                          tmp = t_1
                      else if ((a - 0.5d0) <= 1d+55) then
                          tmp = -t
                      else
                          tmp = t_1
                      end if
                      code = tmp
                  end function
                  
                  public static double code(double x, double y, double z, double t, double a) {
                  	double t_1 = Math.log(t) * a;
                  	double tmp;
                  	if ((a - 0.5) <= -2e+23) {
                  		tmp = t_1;
                  	} else if ((a - 0.5) <= 1e+55) {
                  		tmp = -t;
                  	} else {
                  		tmp = t_1;
                  	}
                  	return tmp;
                  }
                  
                  def code(x, y, z, t, a):
                  	t_1 = math.log(t) * a
                  	tmp = 0
                  	if (a - 0.5) <= -2e+23:
                  		tmp = t_1
                  	elif (a - 0.5) <= 1e+55:
                  		tmp = -t
                  	else:
                  		tmp = t_1
                  	return tmp
                  
                  function code(x, y, z, t, a)
                  	t_1 = Float64(log(t) * a)
                  	tmp = 0.0
                  	if (Float64(a - 0.5) <= -2e+23)
                  		tmp = t_1;
                  	elseif (Float64(a - 0.5) <= 1e+55)
                  		tmp = Float64(-t);
                  	else
                  		tmp = t_1;
                  	end
                  	return tmp
                  end
                  
                  function tmp_2 = code(x, y, z, t, a)
                  	t_1 = log(t) * a;
                  	tmp = 0.0;
                  	if ((a - 0.5) <= -2e+23)
                  		tmp = t_1;
                  	elseif ((a - 0.5) <= 1e+55)
                  		tmp = -t;
                  	else
                  		tmp = t_1;
                  	end
                  	tmp_2 = tmp;
                  end
                  
                  code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision]}, If[LessEqual[N[(a - 0.5), $MachinePrecision], -2e+23], t$95$1, If[LessEqual[N[(a - 0.5), $MachinePrecision], 1e+55], (-t), t$95$1]]]
                  
                  \begin{array}{l}
                  
                  \\
                  \begin{array}{l}
                  t_1 := \log t \cdot a\\
                  \mathbf{if}\;a - 0.5 \leq -2 \cdot 10^{+23}:\\
                  \;\;\;\;t\_1\\
                  
                  \mathbf{elif}\;a - 0.5 \leq 10^{+55}:\\
                  \;\;\;\;-t\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;t\_1\\
                  
                  
                  \end{array}
                  \end{array}
                  
                  Derivation
                  1. Split input into 2 regimes
                  2. if (-.f64 a #s(literal 1/2 binary64)) < -1.9999999999999998e23 or 1.00000000000000001e55 < (-.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. lower-*.f64N/A

                        \[\leadsto \color{blue}{a \cdot \log t} \]
                      2. lower-log.f6481.6

                        \[\leadsto a \cdot \color{blue}{\log t} \]
                    5. Applied rewrites81.6%

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

                    if -1.9999999999999998e23 < (-.f64 a #s(literal 1/2 binary64)) < 1.00000000000000001e55

                    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.f6456.0

                        \[\leadsto \color{blue}{-t} \]
                    5. Applied rewrites56.0%

                      \[\leadsto \color{blue}{-t} \]
                  3. Recombined 2 regimes into one program.
                  4. Final simplification66.7%

                    \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -2 \cdot 10^{+23}:\\ \;\;\;\;\log t \cdot a\\ \mathbf{elif}\;a - 0.5 \leq 10^{+55}:\\ \;\;\;\;-t\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \]
                  5. Add Preprocessing

                  Alternative 11: 76.7% accurate, 2.9× speedup?

                  \[\begin{array}{l} \\ \mathsf{fma}\left(a - 0.5, \log t, -t\right) \end{array} \]
                  (FPCore (x y z t a) :precision binary64 (fma (- a 0.5) (log t) (- t)))
                  double code(double x, double y, double z, double t, double a) {
                  	return fma((a - 0.5), log(t), -t);
                  }
                  
                  function code(x, y, z, t, a)
                  	return fma(Float64(a - 0.5), log(t), Float64(-t))
                  end
                  
                  code[x_, y_, z_, t_, a_] := N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + (-t)), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \mathsf{fma}\left(a - 0.5, \log t, -t\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. 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-/.f6499.6

                      \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
                  4. Applied rewrites99.6%

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

                    \[\leadsto \color{blue}{-1 \cdot t} + \frac{\log t}{\frac{1}{a - \frac{1}{2}}} \]
                  6. Step-by-step derivation
                    1. mul-1-negN/A

                      \[\leadsto \color{blue}{\left(\mathsf{neg}\left(t\right)\right)} + \frac{\log t}{\frac{1}{a - \frac{1}{2}}} \]
                    2. lower-neg.f6478.1

                      \[\leadsto \color{blue}{\left(-t\right)} + \frac{\log t}{\frac{1}{a - 0.5}} \]
                  7. Applied rewrites78.1%

                    \[\leadsto \color{blue}{\left(-t\right)} + \frac{\log t}{\frac{1}{a - 0.5}} \]
                  8. Step-by-step derivation
                    1. lift-+.f64N/A

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

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

                      \[\leadsto \color{blue}{\frac{\log t}{\frac{1}{a - \frac{1}{2}}}} + \left(\mathsf{neg}\left(t\right)\right) \]
                    4. lift-/.f64N/A

                      \[\leadsto \frac{\log t}{\color{blue}{\frac{1}{a - \frac{1}{2}}}} + \left(\mathsf{neg}\left(t\right)\right) \]
                    5. associate-/r/N/A

                      \[\leadsto \color{blue}{\frac{\log t}{1} \cdot \left(a - \frac{1}{2}\right)} + \left(\mathsf{neg}\left(t\right)\right) \]
                    6. /-rgt-identityN/A

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

                      \[\leadsto \color{blue}{\left(a - \frac{1}{2}\right) \cdot \log t} + \left(\mathsf{neg}\left(t\right)\right) \]
                    8. lower-fma.f6478.2

                      \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, -t\right)} \]
                  9. Applied rewrites78.2%

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

                  Alternative 12: 74.1% accurate, 2.9× speedup?

                  \[\begin{array}{l} \\ \log t \cdot a - t \end{array} \]
                  (FPCore (x y z t a) :precision binary64 (- (* (log t) a) t))
                  double code(double x, double y, double z, double t, double a) {
                  	return (log(t) * a) - 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(t) * a) - t
                  end function
                  
                  public static double code(double x, double y, double z, double t, double a) {
                  	return (Math.log(t) * a) - t;
                  }
                  
                  def code(x, y, z, t, a):
                  	return (math.log(t) * a) - t
                  
                  function code(x, y, z, t, a)
                  	return Float64(Float64(log(t) * a) - t)
                  end
                  
                  function tmp = code(x, y, z, t, a)
                  	tmp = (log(t) * a) - t;
                  end
                  
                  code[x_, y_, z_, t_, a_] := N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] - t), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \log t \cdot a - 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. 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-/.f6499.6

                      \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \frac{\log t}{\color{blue}{\frac{1}{a - 0.5}}} \]
                  4. Applied rewrites99.6%

                    \[\leadsto \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \color{blue}{\frac{\log t}{\frac{1}{a - 0.5}}} \]
                  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. lower--.f64N/A

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

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

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

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

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

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

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

                      \[\leadsto \left(\log y + \mathsf{fma}\left(a - \frac{1}{2}, \color{blue}{\log t}, \log z\right)\right) - t \]
                    9. lower-log.f6467.1

                      \[\leadsto \left(\log y + \mathsf{fma}\left(a - 0.5, \log t, \color{blue}{\log z}\right)\right) - t \]
                  7. Applied rewrites67.1%

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

                    \[\leadsto a \cdot \log t - t \]
                  9. Step-by-step derivation
                    1. Applied rewrites75.8%

                      \[\leadsto a \cdot \log t - t \]
                    2. Final simplification75.8%

                      \[\leadsto \log t \cdot a - t \]
                    3. Add Preprocessing

                    Alternative 13: 37.2% 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.f6440.2

                        \[\leadsto \color{blue}{-t} \]
                    5. Applied rewrites40.2%

                      \[\leadsto \color{blue}{-t} \]
                    6. 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 2024235 
                    (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))))