Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 13.1s
Alternatives: 12
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 12 alternatives:

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

Initial Program: 99.6% accurate, 1.0× speedup?

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

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

Alternative 1: 99.6% accurate, 1.0× speedup?

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

\\
\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t
\end{array}
Derivation
  1. Initial program 99.6%

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

Alternative 2: 71.1% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{if}\;t\_1 \leq -5000000000000:\\ \;\;\;\;-t\\ \mathbf{elif}\;t\_1 \leq 700:\\ \;\;\;\;\log \left(\left(y + x\right) \cdot \left(\sqrt{{t}^{-1}} \cdot z\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t)))))
   (if (<= t_1 -5000000000000.0)
     (- t)
     (if (<= t_1 700.0)
       (log (* (+ y x) (* (sqrt (pow t -1.0)) z)))
       (* (log t) a)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
	double tmp;
	if (t_1 <= -5000000000000.0) {
		tmp = -t;
	} else if (t_1 <= 700.0) {
		tmp = log(((y + x) * (sqrt(pow(t, -1.0)) * z)));
	} else {
		tmp = log(t) * a;
	}
	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((x + y)) + log(z)) - t) + ((a - 0.5d0) * log(t))
    if (t_1 <= (-5000000000000.0d0)) then
        tmp = -t
    else if (t_1 <= 700.0d0) then
        tmp = log(((y + x) * (sqrt((t ** (-1.0d0))) * z)))
    else
        tmp = log(t) * a
    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((x + y)) + Math.log(z)) - t) + ((a - 0.5) * Math.log(t));
	double tmp;
	if (t_1 <= -5000000000000.0) {
		tmp = -t;
	} else if (t_1 <= 700.0) {
		tmp = Math.log(((y + x) * (Math.sqrt(Math.pow(t, -1.0)) * z)));
	} else {
		tmp = Math.log(t) * a;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = ((math.log((x + y)) + math.log(z)) - t) + ((a - 0.5) * math.log(t))
	tmp = 0
	if t_1 <= -5000000000000.0:
		tmp = -t
	elif t_1 <= 700.0:
		tmp = math.log(((y + x) * (math.sqrt(math.pow(t, -1.0)) * z)))
	else:
		tmp = math.log(t) * a
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
	tmp = 0.0
	if (t_1 <= -5000000000000.0)
		tmp = Float64(-t);
	elseif (t_1 <= 700.0)
		tmp = log(Float64(Float64(y + x) * Float64(sqrt((t ^ -1.0)) * z)));
	else
		tmp = Float64(log(t) * a);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
	tmp = 0.0;
	if (t_1 <= -5000000000000.0)
		tmp = -t;
	elseif (t_1 <= 700.0)
		tmp = log(((y + x) * (sqrt((t ^ -1.0)) * z)));
	else
		tmp = log(t) * a;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, -5000000000000.0], (-t), If[LessEqual[t$95$1, 700.0], N[Log[N[(N[(y + x), $MachinePrecision] * N[(N[Sqrt[N[Power[t, -1.0], $MachinePrecision]], $MachinePrecision] * z), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\
\mathbf{if}\;t\_1 \leq -5000000000000:\\
\;\;\;\;-t\\

\mathbf{elif}\;t\_1 \leq 700:\\
\;\;\;\;\log \left(\left(y + x\right) \cdot \left(\sqrt{{t}^{-1}} \cdot z\right)\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < -5e12

    1. Initial program 99.8%

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

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

        \[\leadsto \color{blue}{\mathsf{neg}\left(t\right)} \]
      2. lower-neg.f6465.3

        \[\leadsto \color{blue}{-t} \]
    5. Applied rewrites65.3%

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

    if -5e12 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 700

    1. Initial program 98.7%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log \color{blue}{\left(y + x\right)}\right) + \log z \]
      16. lower-log.f6496.2

        \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log \left(y + x\right)\right) + \color{blue}{\log z} \]
    5. Applied rewrites96.2%

      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log \left(y + x\right)\right) + \log z} \]
    6. Step-by-step derivation
      1. Applied rewrites95.0%

        \[\leadsto \log \left(\left(y + x\right) \cdot \left({t}^{\left(-0.5 + a\right)} \cdot z\right)\right) \]
      2. Taylor expanded in a around 0

        \[\leadsto \log \left(\left(y + x\right) \cdot \left(\sqrt{\frac{1}{t}} \cdot z\right)\right) \]
      3. Step-by-step derivation
        1. Applied rewrites93.1%

          \[\leadsto \log \left(\left(y + x\right) \cdot \left(\sqrt{\frac{1}{t}} \cdot z\right)\right) \]

        if 700 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t)))

        1. Initial program 99.6%

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

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

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

            \[\leadsto \color{blue}{\log t \cdot a} \]
          3. lower-log.f6466.2

            \[\leadsto \color{blue}{\log t} \cdot a \]
        5. Applied rewrites66.2%

          \[\leadsto \color{blue}{\log t \cdot a} \]
      4. Recombined 3 regimes into one program.
      5. Final simplification69.7%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq -5000000000000:\\ \;\;\;\;-t\\ \mathbf{elif}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq 700:\\ \;\;\;\;\log \left(\left(y + x\right) \cdot \left(\sqrt{{t}^{-1}} \cdot z\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \]
      6. Add Preprocessing

      Alternative 3: 84.3% accurate, 0.4× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 673.8\right):\\ \;\;\;\;\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \log y\\ \mathbf{else}:\\ \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\ \end{array} \end{array} \]
      (FPCore (x y z t a)
       :precision binary64
       (let* ((t_1 (+ (log (+ x y)) (log z))))
         (if (or (<= t_1 -750.0) (not (<= t_1 673.8)))
           (+ (fma (+ -0.5 a) (log t) (log z)) (log y))
           (- (log (* z (+ y x))) (- t (* (log t) (- a 0.5)))))))
      double code(double x, double y, double z, double t, double a) {
      	double t_1 = log((x + y)) + log(z);
      	double tmp;
      	if ((t_1 <= -750.0) || !(t_1 <= 673.8)) {
      		tmp = fma((-0.5 + a), log(t), log(z)) + log(y);
      	} else {
      		tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5)));
      	}
      	return tmp;
      }
      
      function code(x, y, z, t, a)
      	t_1 = Float64(log(Float64(x + y)) + log(z))
      	tmp = 0.0
      	if ((t_1 <= -750.0) || !(t_1 <= 673.8))
      		tmp = Float64(fma(Float64(-0.5 + a), log(t), log(z)) + log(y));
      	else
      		tmp = Float64(log(Float64(z * Float64(y + x))) - Float64(t - Float64(log(t) * Float64(a - 0.5))));
      	end
      	return tmp
      end
      
      code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$1, -750.0], N[Not[LessEqual[t$95$1, 673.8]], $MachinePrecision]], N[(N[(N[(-0.5 + a), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision], 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]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_1 := \log \left(x + y\right) + \log z\\
      \mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 673.8\right):\\
      \;\;\;\;\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \log y\\
      
      \mathbf{else}:\\
      \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750 or 673.79999999999995 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

        1. Initial program 99.8%

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

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

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

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

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

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

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

            \[\leadsto \left(\left(a \cdot \log t - \color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)} \cdot \log t\right) + \log z\right) + \left(\log y - t\right) \]
          7. fp-cancel-sign-sub-invN/A

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

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

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

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

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

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

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

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

            \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log z\right) + \color{blue}{\left(\log y - t\right)} \]
          16. lower-log.f6470.5

            \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
        5. Applied rewrites70.5%

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

          \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log z\right) + \log y \]
        7. Step-by-step derivation
          1. Applied rewrites54.4%

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

          if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 673.79999999999995

          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%

            \[\leadsto \color{blue}{\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)} \]
        8. Recombined 2 regimes into one program.
        9. Final simplification89.2%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq -750 \lor \neg \left(\log \left(x + y\right) + \log z \leq 673.8\right):\\ \;\;\;\;\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \log y\\ \mathbf{else}:\\ \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\ \end{array} \]
        10. Add Preprocessing

        Alternative 4: 82.7% accurate, 0.7× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq 673.8:\\ \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \end{array} \]
        (FPCore (x y z t a)
         :precision binary64
         (if (<= (+ (log (+ x y)) (log z)) 673.8)
           (- (log (* z (+ y x))) (- t (* (log t) (- a 0.5))))
           (* (log t) a)))
        double code(double x, double y, double z, double t, double a) {
        	double tmp;
        	if ((log((x + y)) + log(z)) <= 673.8) {
        		tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5)));
        	} else {
        		tmp = log(t) * a;
        	}
        	return tmp;
        }
        
        real(8) function code(x, y, z, t, a)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            real(8), intent (in) :: z
            real(8), intent (in) :: t
            real(8), intent (in) :: a
            real(8) :: tmp
            if ((log((x + y)) + log(z)) <= 673.8d0) then
                tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5d0)))
            else
                tmp = log(t) * a
            end if
            code = tmp
        end function
        
        public static double code(double x, double y, double z, double t, double a) {
        	double tmp;
        	if ((Math.log((x + y)) + Math.log(z)) <= 673.8) {
        		tmp = Math.log((z * (y + x))) - (t - (Math.log(t) * (a - 0.5)));
        	} else {
        		tmp = Math.log(t) * a;
        	}
        	return tmp;
        }
        
        def code(x, y, z, t, a):
        	tmp = 0
        	if (math.log((x + y)) + math.log(z)) <= 673.8:
        		tmp = math.log((z * (y + x))) - (t - (math.log(t) * (a - 0.5)))
        	else:
        		tmp = math.log(t) * a
        	return tmp
        
        function code(x, y, z, t, a)
        	tmp = 0.0
        	if (Float64(log(Float64(x + y)) + log(z)) <= 673.8)
        		tmp = Float64(log(Float64(z * Float64(y + x))) - Float64(t - Float64(log(t) * Float64(a - 0.5))));
        	else
        		tmp = Float64(log(t) * a);
        	end
        	return tmp
        end
        
        function tmp_2 = code(x, y, z, t, a)
        	tmp = 0.0;
        	if ((log((x + y)) + log(z)) <= 673.8)
        		tmp = log((z * (y + x))) - (t - (log(t) * (a - 0.5)));
        	else
        		tmp = log(t) * a;
        	end
        	tmp_2 = tmp;
        end
        
        code[x_, y_, z_, t_, a_] := If[LessEqual[N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision], 673.8], 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[Log[t], $MachinePrecision] * a), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;\log \left(x + y\right) + \log z \leq 673.8:\\
        \;\;\;\;\log \left(z \cdot \left(y + x\right)\right) - \left(t - \log t \cdot \left(a - 0.5\right)\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\log t \cdot a\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 673.79999999999995

          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--.f6496.3

              \[\leadsto \log \left(z \cdot \left(y + x\right)\right) - \color{blue}{\left(t - \left(a - 0.5\right) \cdot \log t\right)} \]
            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-*.f6496.3

              \[\leadsto \log \left(z \cdot \left(y + x\right)\right) - \left(t - \color{blue}{\log t \cdot \left(a - 0.5\right)}\right) \]
          4. Applied rewrites96.3%

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

          if 673.79999999999995 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

          1. Initial program 99.8%

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

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

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

              \[\leadsto \color{blue}{\log t \cdot a} \]
            3. lower-log.f6444.2

              \[\leadsto \color{blue}{\log t} \cdot a \]
          5. Applied rewrites44.2%

            \[\leadsto \color{blue}{\log t \cdot a} \]
        3. Recombined 2 regimes into one program.
        4. Add Preprocessing

        Alternative 5: 82.7% accurate, 0.7× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq 673.8:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \end{array} \]
        (FPCore (x y z t a)
         :precision binary64
         (if (<= (+ (log (+ x y)) (log z)) 673.8)
           (fma (- a 0.5) (log t) (- (log (* z (+ y x))) t))
           (* (log t) a)))
        double code(double x, double y, double z, double t, double a) {
        	double tmp;
        	if ((log((x + y)) + log(z)) <= 673.8) {
        		tmp = fma((a - 0.5), log(t), (log((z * (y + x))) - t));
        	} else {
        		tmp = log(t) * a;
        	}
        	return tmp;
        }
        
        function code(x, y, z, t, a)
        	tmp = 0.0
        	if (Float64(log(Float64(x + y)) + log(z)) <= 673.8)
        		tmp = fma(Float64(a - 0.5), log(t), Float64(log(Float64(z * Float64(y + x))) - t));
        	else
        		tmp = Float64(log(t) * a);
        	end
        	return tmp
        end
        
        code[x_, y_, z_, t_, a_] := If[LessEqual[N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision], 673.8], N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[(N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;\log \left(x + y\right) + \log z \leq 673.8:\\
        \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\log t \cdot a\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 673.79999999999995

          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.f6499.5

              \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \left(\log \left(x + y\right) + \log z\right) - t\right)} \]
            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-*.f6496.3

              \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \color{blue}{\left(z \cdot \left(x + y\right)\right)} - t\right) \]
            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-+.f6496.3

              \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - t\right) \]
          4. Applied rewrites96.3%

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

          if 673.79999999999995 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

          1. Initial program 99.8%

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

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

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

              \[\leadsto \color{blue}{\log t \cdot a} \]
            3. lower-log.f6444.2

              \[\leadsto \color{blue}{\log t} \cdot a \]
          5. Applied rewrites44.2%

            \[\leadsto \color{blue}{\log t \cdot a} \]
        3. Recombined 2 regimes into one program.
        4. Add Preprocessing

        Alternative 6: 57.1% accurate, 0.7× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq 673.8:\\ \;\;\;\;\left(\log \left(z \cdot y\right) - t\right) + \log t \cdot \left(-0.5 + a\right)\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \end{array} \]
        (FPCore (x y z t a)
         :precision binary64
         (if (<= (+ (log (+ x y)) (log z)) 673.8)
           (+ (- (log (* z y)) t) (* (log t) (+ -0.5 a)))
           (* (log t) a)))
        double code(double x, double y, double z, double t, double a) {
        	double tmp;
        	if ((log((x + y)) + log(z)) <= 673.8) {
        		tmp = (log((z * y)) - t) + (log(t) * (-0.5 + a));
        	} else {
        		tmp = log(t) * a;
        	}
        	return tmp;
        }
        
        real(8) function code(x, y, z, t, a)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            real(8), intent (in) :: z
            real(8), intent (in) :: t
            real(8), intent (in) :: a
            real(8) :: tmp
            if ((log((x + y)) + log(z)) <= 673.8d0) then
                tmp = (log((z * y)) - t) + (log(t) * ((-0.5d0) + a))
            else
                tmp = log(t) * a
            end if
            code = tmp
        end function
        
        public static double code(double x, double y, double z, double t, double a) {
        	double tmp;
        	if ((Math.log((x + y)) + Math.log(z)) <= 673.8) {
        		tmp = (Math.log((z * y)) - t) + (Math.log(t) * (-0.5 + a));
        	} else {
        		tmp = Math.log(t) * a;
        	}
        	return tmp;
        }
        
        def code(x, y, z, t, a):
        	tmp = 0
        	if (math.log((x + y)) + math.log(z)) <= 673.8:
        		tmp = (math.log((z * y)) - t) + (math.log(t) * (-0.5 + a))
        	else:
        		tmp = math.log(t) * a
        	return tmp
        
        function code(x, y, z, t, a)
        	tmp = 0.0
        	if (Float64(log(Float64(x + y)) + log(z)) <= 673.8)
        		tmp = Float64(Float64(log(Float64(z * y)) - t) + Float64(log(t) * Float64(-0.5 + a)));
        	else
        		tmp = Float64(log(t) * a);
        	end
        	return tmp
        end
        
        function tmp_2 = code(x, y, z, t, a)
        	tmp = 0.0;
        	if ((log((x + y)) + log(z)) <= 673.8)
        		tmp = (log((z * y)) - t) + (log(t) * (-0.5 + a));
        	else
        		tmp = log(t) * a;
        	end
        	tmp_2 = tmp;
        end
        
        code[x_, y_, z_, t_, a_] := If[LessEqual[N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision], 673.8], N[(N[(N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(-0.5 + a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;\log \left(x + y\right) + \log z \leq 673.8:\\
        \;\;\;\;\left(\log \left(z \cdot y\right) - t\right) + \log t \cdot \left(-0.5 + a\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\log t \cdot a\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 673.79999999999995

          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 x around 0

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

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

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

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

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

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

              \[\leadsto \left(\left(a \cdot \log t - \color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)} \cdot \log t\right) + \log z\right) + \left(\log y - t\right) \]
            7. fp-cancel-sign-sub-invN/A

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

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

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

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

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

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

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

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

              \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log z\right) + \color{blue}{\left(\log y - t\right)} \]
            16. lower-log.f6470.2

              \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
          5. Applied rewrites70.2%

            \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
          6. Step-by-step derivation
            1. Applied rewrites64.7%

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

            if 673.79999999999995 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

            1. Initial program 99.8%

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

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

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

                \[\leadsto \color{blue}{\log t \cdot a} \]
              3. lower-log.f6444.2

                \[\leadsto \color{blue}{\log t} \cdot a \]
            5. Applied rewrites44.2%

              \[\leadsto \color{blue}{\log t \cdot a} \]
          7. Recombined 2 regimes into one program.
          8. Add Preprocessing

          Alternative 7: 57.1% accurate, 0.7× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq 673.8:\\ \;\;\;\;\mathsf{fma}\left(-0.5 + a, \log t, \log \left(z \cdot y\right) - t\right)\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \end{array} \]
          (FPCore (x y z t a)
           :precision binary64
           (if (<= (+ (log (+ x y)) (log z)) 673.8)
             (fma (+ -0.5 a) (log t) (- (log (* z y)) t))
             (* (log t) a)))
          double code(double x, double y, double z, double t, double a) {
          	double tmp;
          	if ((log((x + y)) + log(z)) <= 673.8) {
          		tmp = fma((-0.5 + a), log(t), (log((z * y)) - t));
          	} else {
          		tmp = log(t) * a;
          	}
          	return tmp;
          }
          
          function code(x, y, z, t, a)
          	tmp = 0.0
          	if (Float64(log(Float64(x + y)) + log(z)) <= 673.8)
          		tmp = fma(Float64(-0.5 + a), log(t), Float64(log(Float64(z * y)) - t));
          	else
          		tmp = Float64(log(t) * a);
          	end
          	return tmp
          end
          
          code[x_, y_, z_, t_, a_] := If[LessEqual[N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision], 673.8], N[(N[(-0.5 + a), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[(N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;\log \left(x + y\right) + \log z \leq 673.8:\\
          \;\;\;\;\mathsf{fma}\left(-0.5 + a, \log t, \log \left(z \cdot y\right) - t\right)\\
          
          \mathbf{else}:\\
          \;\;\;\;\log t \cdot a\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 673.79999999999995

            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 x around 0

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

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

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

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

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

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

                \[\leadsto \left(\left(a \cdot \log t - \color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)} \cdot \log t\right) + \log z\right) + \left(\log y - t\right) \]
              7. fp-cancel-sign-sub-invN/A

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

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

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

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

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

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

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

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

                \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log z\right) + \color{blue}{\left(\log y - t\right)} \]
              16. lower-log.f6470.2

                \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
            5. Applied rewrites70.2%

              \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
            6. Step-by-step derivation
              1. Applied rewrites64.7%

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

              if 673.79999999999995 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

              1. Initial program 99.8%

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

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

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

                  \[\leadsto \color{blue}{\log t \cdot a} \]
                3. lower-log.f6444.2

                  \[\leadsto \color{blue}{\log t} \cdot a \]
              5. Applied rewrites44.2%

                \[\leadsto \color{blue}{\log t \cdot a} \]
            7. Recombined 2 regimes into one program.
            8. Add Preprocessing

            Alternative 8: 68.3% accurate, 1.0× speedup?

            \[\begin{array}{l} \\ \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right) \end{array} \]
            (FPCore (x y z t a)
             :precision binary64
             (+ (fma (+ -0.5 a) (log t) (log z)) (- (log y) t)))
            double code(double x, double y, double z, double t, double a) {
            	return fma((-0.5 + a), log(t), log(z)) + (log(y) - t);
            }
            
            function code(x, y, z, t, a)
            	return Float64(fma(Float64(-0.5 + a), log(t), log(z)) + Float64(log(y) - t))
            end
            
            code[x_, y_, z_, t_, a_] := N[(N[(N[(-0.5 + a), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] + N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)
            \end{array}
            
            Derivation
            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 x around 0

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

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

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

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

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

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

                \[\leadsto \left(\left(a \cdot \log t - \color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)} \cdot \log t\right) + \log z\right) + \left(\log y - t\right) \]
              7. fp-cancel-sign-sub-invN/A

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

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

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

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

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

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

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

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

                \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log z\right) + \color{blue}{\left(\log y - t\right)} \]
              16. lower-log.f6470.6

                \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
            5. Applied rewrites70.6%

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

            Alternative 9: 68.3% accurate, 1.0× speedup?

            \[\begin{array}{l} \\ \log z + \mathsf{fma}\left(\log t, -0.5 + a, \log y - t\right) \end{array} \]
            (FPCore (x y z t a)
             :precision binary64
             (+ (log z) (fma (log t) (+ -0.5 a) (- (log y) t))))
            double code(double x, double y, double z, double t, double a) {
            	return log(z) + fma(log(t), (-0.5 + a), (log(y) - t));
            }
            
            function code(x, y, z, t, a)
            	return Float64(log(z) + fma(log(t), Float64(-0.5 + a), Float64(log(y) - t)))
            end
            
            code[x_, y_, z_, t_, a_] := N[(N[Log[z], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(-0.5 + a), $MachinePrecision] + N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \log z + \mathsf{fma}\left(\log t, -0.5 + a, \log y - t\right)
            \end{array}
            
            Derivation
            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 x around 0

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

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

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

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

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

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

                \[\leadsto \left(\left(a \cdot \log t - \color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)} \cdot \log t\right) + \log z\right) + \left(\log y - t\right) \]
              7. fp-cancel-sign-sub-invN/A

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

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

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

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

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

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

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

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

                \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log z\right) + \color{blue}{\left(\log y - t\right)} \]
              16. lower-log.f6470.6

                \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
            5. Applied rewrites70.6%

              \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
            6. Step-by-step derivation
              1. Applied rewrites70.6%

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

              Alternative 10: 61.0% accurate, 1.5× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 3.25 \cdot 10^{+18}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right)\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
              (FPCore (x y z t a)
               :precision binary64
               (if (<= t 3.25e+18) (fma (log t) (- a 0.5) (log (* z y))) (- t)))
              double code(double x, double y, double z, double t, double a) {
              	double tmp;
              	if (t <= 3.25e+18) {
              		tmp = fma(log(t), (a - 0.5), log((z * y)));
              	} else {
              		tmp = -t;
              	}
              	return tmp;
              }
              
              function code(x, y, z, t, a)
              	tmp = 0.0
              	if (t <= 3.25e+18)
              		tmp = fma(log(t), Float64(a - 0.5), log(Float64(z * y)));
              	else
              		tmp = Float64(-t);
              	end
              	return tmp
              end
              
              code[x_, y_, z_, t_, a_] := If[LessEqual[t, 3.25e+18], N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], (-t)]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              \mathbf{if}\;t \leq 3.25 \cdot 10^{+18}:\\
              \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;-t\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if t < 3.25e18

                1. Initial program 99.3%

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

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

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

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

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

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

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

                    \[\leadsto \left(\left(a \cdot \log t - \color{blue}{\left(\mathsf{neg}\left(\frac{-1}{2}\right)\right)} \cdot \log t\right) + \log z\right) + \left(\log y - t\right) \]
                  7. fp-cancel-sign-sub-invN/A

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

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

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

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

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

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

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

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

                    \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log z\right) + \color{blue}{\left(\log y - t\right)} \]
                  16. lower-log.f6467.5

                    \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
                5. Applied rewrites67.5%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
                6. Step-by-step derivation
                  1. Applied rewrites51.4%

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

                    \[\leadsto \log \left(y \cdot z\right) + \color{blue}{\log t \cdot \left(a - \frac{1}{2}\right)} \]
                  3. Step-by-step derivation
                    1. Applied rewrites50.2%

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

                    if 3.25e18 < t

                    1. Initial program 99.8%

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

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

                        \[\leadsto \color{blue}{\mathsf{neg}\left(t\right)} \]
                      2. lower-neg.f6471.8

                        \[\leadsto \color{blue}{-t} \]
                    5. Applied rewrites71.8%

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

                  Alternative 11: 62.7% accurate, 2.9× speedup?

                  \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 3.7 \cdot 10^{+18}:\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
                  (FPCore (x y z t a)
                   :precision binary64
                   (if (<= t 3.7e+18) (* (log t) a) (- t)))
                  double code(double x, double y, double z, double t, double a) {
                  	double tmp;
                  	if (t <= 3.7e+18) {
                  		tmp = log(t) * a;
                  	} else {
                  		tmp = -t;
                  	}
                  	return tmp;
                  }
                  
                  real(8) function code(x, y, z, t, a)
                      real(8), intent (in) :: x
                      real(8), intent (in) :: y
                      real(8), intent (in) :: z
                      real(8), intent (in) :: t
                      real(8), intent (in) :: a
                      real(8) :: tmp
                      if (t <= 3.7d+18) then
                          tmp = log(t) * a
                      else
                          tmp = -t
                      end if
                      code = tmp
                  end function
                  
                  public static double code(double x, double y, double z, double t, double a) {
                  	double tmp;
                  	if (t <= 3.7e+18) {
                  		tmp = Math.log(t) * a;
                  	} else {
                  		tmp = -t;
                  	}
                  	return tmp;
                  }
                  
                  def code(x, y, z, t, a):
                  	tmp = 0
                  	if t <= 3.7e+18:
                  		tmp = math.log(t) * a
                  	else:
                  		tmp = -t
                  	return tmp
                  
                  function code(x, y, z, t, a)
                  	tmp = 0.0
                  	if (t <= 3.7e+18)
                  		tmp = Float64(log(t) * a);
                  	else
                  		tmp = Float64(-t);
                  	end
                  	return tmp
                  end
                  
                  function tmp_2 = code(x, y, z, t, a)
                  	tmp = 0.0;
                  	if (t <= 3.7e+18)
                  		tmp = log(t) * a;
                  	else
                  		tmp = -t;
                  	end
                  	tmp_2 = tmp;
                  end
                  
                  code[x_, y_, z_, t_, a_] := If[LessEqual[t, 3.7e+18], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision], (-t)]
                  
                  \begin{array}{l}
                  
                  \\
                  \begin{array}{l}
                  \mathbf{if}\;t \leq 3.7 \cdot 10^{+18}:\\
                  \;\;\;\;\log t \cdot a\\
                  
                  \mathbf{else}:\\
                  \;\;\;\;-t\\
                  
                  
                  \end{array}
                  \end{array}
                  
                  Derivation
                  1. Split input into 2 regimes
                  2. if t < 3.7e18

                    1. Initial program 99.3%

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

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

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

                        \[\leadsto \color{blue}{\log t \cdot a} \]
                      3. lower-log.f6452.6

                        \[\leadsto \color{blue}{\log t} \cdot a \]
                    5. Applied rewrites52.6%

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

                    if 3.7e18 < t

                    1. Initial program 99.8%

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

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

                        \[\leadsto \color{blue}{\mathsf{neg}\left(t\right)} \]
                      2. lower-neg.f6471.8

                        \[\leadsto \color{blue}{-t} \]
                    5. Applied rewrites71.8%

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

                  Alternative 12: 37.6% 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 99.6%

                    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                  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.f6439.0

                      \[\leadsto \color{blue}{-t} \]
                  5. Applied rewrites39.0%

                    \[\leadsto \color{blue}{-t} \]
                  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 2024337 
                  (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))))