Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 11.8s
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?

\[\begin{array}{l} \\ \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \end{array} \]
(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: 74.2% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right)\\ t_2 := \left(\left(t\_1 + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{if}\;t\_2 \leq -1000000:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot y\right)\right) - t\\ \mathbf{elif}\;t\_2 \leq 2000:\\ \;\;\;\;\mathsf{fma}\left(-0.5, \log t, t\_1\right) + \log z\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (log (+ x y)))
        (t_2 (+ (- (+ t_1 (log z)) t) (* (- a 0.5) (log t)))))
   (if (<= t_2 -1000000.0)
     (- (fma (- a 0.5) (log t) (log (* z y))) t)
     (if (<= t_2 2000.0) (+ (fma -0.5 (log t) t_1) (log z)) (* (log t) a)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = log((x + y));
	double t_2 = ((t_1 + log(z)) - t) + ((a - 0.5) * log(t));
	double tmp;
	if (t_2 <= -1000000.0) {
		tmp = fma((a - 0.5), log(t), log((z * y))) - t;
	} else if (t_2 <= 2000.0) {
		tmp = fma(-0.5, log(t), t_1) + log(z);
	} else {
		tmp = log(t) * a;
	}
	return tmp;
}
function code(x, y, z, t, a)
	t_1 = log(Float64(x + y))
	t_2 = Float64(Float64(Float64(t_1 + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
	tmp = 0.0
	if (t_2 <= -1000000.0)
		tmp = Float64(fma(Float64(a - 0.5), log(t), log(Float64(z * y))) - t);
	elseif (t_2 <= 2000.0)
		tmp = Float64(fma(-0.5, log(t), t_1) + log(z));
	else
		tmp = Float64(log(t) * a);
	end
	return tmp
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[(N[(N[(t$95$1 + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$2, -1000000.0], N[(N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[t$95$2, 2000.0], N[(N[(-0.5 * N[Log[t], $MachinePrecision] + t$95$1), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \log \left(x + y\right)\\
t_2 := \left(\left(t\_1 + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\
\mathbf{if}\;t\_2 \leq -1000000:\\
\;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot y\right)\right) - t\\

\mathbf{elif}\;t\_2 \leq 2000:\\
\;\;\;\;\mathsf{fma}\left(-0.5, \log t, t\_1\right) + \log z\\

\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))) < -1e6

    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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \color{blue}{\left(y + x\right)}\right) + \left(\log z - t\right) \]
      14. lower--.f6499.9

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

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

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

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

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

        \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(y + x\right)\right) + \log z\right) - t} \]
    6. Applied rewrites74.9%

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

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

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
      3. lower-*.f6451.3

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
    9. Applied rewrites51.3%

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

    if -1e6 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 2e3

    1. Initial program 99.2%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    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.f6498.8

        \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log \left(y + x\right)\right) + \color{blue}{\log z} \]
    5. Applied rewrites98.8%

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

      \[\leadsto \log z + \color{blue}{\left(\log \left(x + y\right) + \frac{-1}{2} \cdot \log t\right)} \]
    7. Step-by-step derivation
      1. Applied rewrites96.8%

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

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

      1. Initial program 99.5%

        \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      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.f6498.2

          \[\leadsto \color{blue}{\log t} \cdot a \]
      5. Applied rewrites98.2%

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

    Alternative 3: 84.3% accurate, 0.5× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -800:\\ \;\;\;\;-t\\ \mathbf{elif}\;t\_1 \leq 700:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \left(y + x\right)\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (let* ((t_1 (+ (log (+ x y)) (log z))))
       (if (<= t_1 -800.0)
         (- t)
         (if (<= t_1 700.0)
           (- (fma (log t) (- a 0.5) (log (* z (+ y x)))) t)
           (* (log t) a)))))
    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 <= -800.0) {
    		tmp = -t;
    	} else if (t_1 <= 700.0) {
    		tmp = fma(log(t), (a - 0.5), log((z * (y + x)))) - t;
    	} else {
    		tmp = log(t) * a;
    	}
    	return tmp;
    }
    
    function code(x, y, z, t, a)
    	t_1 = Float64(log(Float64(x + y)) + log(z))
    	tmp = 0.0
    	if (t_1 <= -800.0)
    		tmp = Float64(-t);
    	elseif (t_1 <= 700.0)
    		tmp = Float64(fma(log(t), Float64(a - 0.5), log(Float64(z * Float64(y + x)))) - t);
    	else
    		tmp = Float64(log(t) * a);
    	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[LessEqual[t$95$1, -800.0], (-t), If[LessEqual[t$95$1, 700.0], N[(N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision]]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_1 := \log \left(x + y\right) + \log z\\
    \mathbf{if}\;t\_1 \leq -800:\\
    \;\;\;\;-t\\
    
    \mathbf{elif}\;t\_1 \leq 700:\\
    \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \left(y + x\right)\right)\right) - t\\
    
    \mathbf{else}:\\
    \;\;\;\;\log t \cdot a\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -800

      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.f6444.4

          \[\leadsto \color{blue}{-t} \]
      5. Applied rewrites44.4%

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

      if -800 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 700

      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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

      if 700 < (+.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.f6439.4

          \[\leadsto \color{blue}{\log t} \cdot a \]
      5. Applied rewrites39.4%

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

    Alternative 4: 58.1% accurate, 0.5× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -800:\\ \;\;\;\;-t\\ \mathbf{elif}\;t\_1 \leq 700:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot y\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\log t \cdot a\\ \end{array} \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (let* ((t_1 (+ (log (+ x y)) (log z))))
       (if (<= t_1 -800.0)
         (- t)
         (if (<= t_1 700.0)
           (- (fma (- a 0.5) (log t) (log (* z y))) t)
           (* (log t) a)))))
    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 <= -800.0) {
    		tmp = -t;
    	} else if (t_1 <= 700.0) {
    		tmp = fma((a - 0.5), log(t), log((z * y))) - t;
    	} else {
    		tmp = log(t) * a;
    	}
    	return tmp;
    }
    
    function code(x, y, z, t, a)
    	t_1 = Float64(log(Float64(x + y)) + log(z))
    	tmp = 0.0
    	if (t_1 <= -800.0)
    		tmp = Float64(-t);
    	elseif (t_1 <= 700.0)
    		tmp = Float64(fma(Float64(a - 0.5), log(t), log(Float64(z * y))) - t);
    	else
    		tmp = Float64(log(t) * a);
    	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[LessEqual[t$95$1, -800.0], (-t), If[LessEqual[t$95$1, 700.0], N[(N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision]]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_1 := \log \left(x + y\right) + \log z\\
    \mathbf{if}\;t\_1 \leq -800:\\
    \;\;\;\;-t\\
    
    \mathbf{elif}\;t\_1 \leq 700:\\
    \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot y\right)\right) - t\\
    
    \mathbf{else}:\\
    \;\;\;\;\log t \cdot a\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -800

      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.f6444.4

          \[\leadsto \color{blue}{-t} \]
      5. Applied rewrites44.4%

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

      if -800 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 700

      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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

          \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
        3. lower-*.f6456.5

          \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
      9. Applied rewrites56.5%

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

      if 700 < (+.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.f6439.4

          \[\leadsto \color{blue}{\log t} \cdot a \]
      5. Applied rewrites39.4%

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

    Alternative 5: 69.0% accurate, 1.0× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 7.5 \cdot 10^{-6}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\\ \mathbf{elif}\;t \leq 1.6 \cdot 10^{+227}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \left(y + x\right)\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log y\right) + \left(\log z - t\right)\\ \end{array} \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (if (<= t 7.5e-6)
       (+ (fma (log t) (- a 0.5) (log z)) (log y))
       (if (<= t 1.6e+227)
         (- (fma (log t) (- a 0.5) (log (* z (+ y x)))) t)
         (+ (fma -0.5 (log t) (log y)) (- (log z) t)))))
    double code(double x, double y, double z, double t, double a) {
    	double tmp;
    	if (t <= 7.5e-6) {
    		tmp = fma(log(t), (a - 0.5), log(z)) + log(y);
    	} else if (t <= 1.6e+227) {
    		tmp = fma(log(t), (a - 0.5), log((z * (y + x)))) - t;
    	} else {
    		tmp = fma(-0.5, log(t), log(y)) + (log(z) - t);
    	}
    	return tmp;
    }
    
    function code(x, y, z, t, a)
    	tmp = 0.0
    	if (t <= 7.5e-6)
    		tmp = Float64(fma(log(t), Float64(a - 0.5), log(z)) + log(y));
    	elseif (t <= 1.6e+227)
    		tmp = Float64(fma(log(t), Float64(a - 0.5), log(Float64(z * Float64(y + x)))) - t);
    	else
    		tmp = Float64(fma(-0.5, log(t), log(y)) + Float64(log(z) - t));
    	end
    	return tmp
    end
    
    code[x_, y_, z_, t_, a_] := If[LessEqual[t, 7.5e-6], N[(N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision], If[LessEqual[t, 1.6e+227], N[(N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(-0.5 * N[Log[t], $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] + N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;t \leq 7.5 \cdot 10^{-6}:\\
    \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\\
    
    \mathbf{elif}\;t \leq 1.6 \cdot 10^{+227}:\\
    \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \left(y + x\right)\right)\right) - t\\
    
    \mathbf{else}:\\
    \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log y\right) + \left(\log z - t\right)\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if t < 7.50000000000000019e-6

      1. Initial program 99.4%

        \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      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.f6499.2

          \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log \left(y + x\right)\right) + \color{blue}{\log z} \]
      5. Applied rewrites99.2%

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

        \[\leadsto \log y + \color{blue}{\left(\log z + \log t \cdot \left(a - \frac{1}{2}\right)\right)} \]
      7. Step-by-step derivation
        1. Applied rewrites60.4%

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

        if 7.50000000000000019e-6 < t < 1.59999999999999994e227

        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

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

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

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

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

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

            \[\leadsto \left(\color{blue}{\log t \cdot \left(a - \frac{1}{2}\right)} + \left(\log \left(x + y\right) + \log z\right)\right) - t \]
          8. lower-fma.f6499.9

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

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

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

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

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

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

            \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \color{blue}{\left(z \cdot \left(x + y\right)\right)}\right) - t \]
          15. lower-*.f6479.7

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

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

            \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right)\right) - t \]
          18. lower-+.f6479.7

            \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right)\right) - t \]
        4. Applied rewrites79.7%

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

        if 1.59999999999999994e227 < 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

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \color{blue}{\left(y + x\right)}\right) + \left(\log z - t\right) \]
          14. lower--.f6499.9

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

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

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

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

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

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

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

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

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

          \[\leadsto \left(\log y + \color{blue}{\frac{-1}{2} \cdot \log t}\right) + \left(\log z - t\right) \]
        9. Step-by-step derivation
          1. Applied rewrites55.8%

            \[\leadsto \mathsf{fma}\left(-0.5, \color{blue}{\log t}, \log y\right) + \left(\log z - t\right) \]
        10. Recombined 3 regimes into one program.
        11. Add Preprocessing

        Alternative 6: 72.2% accurate, 1.0× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 7.5 \cdot 10^{-6}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\\ \mathbf{elif}\;t \leq 1.6 \cdot 10^{+227}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \left(y + x\right)\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
        (FPCore (x y z t a)
         :precision binary64
         (if (<= t 7.5e-6)
           (+ (fma (log t) (- a 0.5) (log z)) (log y))
           (if (<= t 1.6e+227)
             (- (fma (log t) (- a 0.5) (log (* z (+ y x)))) t)
             (- t))))
        double code(double x, double y, double z, double t, double a) {
        	double tmp;
        	if (t <= 7.5e-6) {
        		tmp = fma(log(t), (a - 0.5), log(z)) + log(y);
        	} else if (t <= 1.6e+227) {
        		tmp = fma(log(t), (a - 0.5), log((z * (y + x)))) - t;
        	} else {
        		tmp = -t;
        	}
        	return tmp;
        }
        
        function code(x, y, z, t, a)
        	tmp = 0.0
        	if (t <= 7.5e-6)
        		tmp = Float64(fma(log(t), Float64(a - 0.5), log(z)) + log(y));
        	elseif (t <= 1.6e+227)
        		tmp = Float64(fma(log(t), Float64(a - 0.5), log(Float64(z * Float64(y + x)))) - t);
        	else
        		tmp = Float64(-t);
        	end
        	return tmp
        end
        
        code[x_, y_, z_, t_, a_] := If[LessEqual[t, 7.5e-6], N[(N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision], If[LessEqual[t, 1.6e+227], N[(N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], (-t)]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;t \leq 7.5 \cdot 10^{-6}:\\
        \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\\
        
        \mathbf{elif}\;t \leq 1.6 \cdot 10^{+227}:\\
        \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \left(y + x\right)\right)\right) - t\\
        
        \mathbf{else}:\\
        \;\;\;\;-t\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 3 regimes
        2. if t < 7.50000000000000019e-6

          1. Initial program 99.4%

            \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
          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.f6499.2

              \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log \left(y + x\right)\right) + \color{blue}{\log z} \]
          5. Applied rewrites99.2%

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

            \[\leadsto \log y + \color{blue}{\left(\log z + \log t \cdot \left(a - \frac{1}{2}\right)\right)} \]
          7. Step-by-step derivation
            1. Applied rewrites60.4%

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

            if 7.50000000000000019e-6 < t < 1.59999999999999994e227

            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

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

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

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

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

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

                \[\leadsto \left(\color{blue}{\log t \cdot \left(a - \frac{1}{2}\right)} + \left(\log \left(x + y\right) + \log z\right)\right) - t \]
              8. lower-fma.f6499.9

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

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

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

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

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

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

                \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \color{blue}{\left(z \cdot \left(x + y\right)\right)}\right) - t \]
              15. lower-*.f6479.7

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

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

                \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right)\right) - t \]
              18. lower-+.f6479.7

                \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right)\right) - t \]
            4. Applied rewrites79.7%

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

            if 1.59999999999999994e227 < t

            1. Initial program 99.9%

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

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

                \[\leadsto \color{blue}{\mathsf{neg}\left(t\right)} \]
              2. lower-neg.f6492.9

                \[\leadsto \color{blue}{-t} \]
            5. Applied rewrites92.9%

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

          Alternative 7: 99.6% accurate, 1.0× speedup?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

          Alternative 8: 68.2% accurate, 1.0× speedup?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

              \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(y + x\right)\right) + \log z\right) - t} \]
          6. Applied rewrites74.0%

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

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

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

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

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

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

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

              \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \color{blue}{\log y} + \log z\right) - t \]
            7. lower-log.f6462.7

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

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

          Alternative 9: 68.2% accurate, 1.0× speedup?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

              \[\leadsto \mathsf{fma}\left(\log t, \color{blue}{a - \frac{1}{2}}, \log y\right) + \left(\log z - t\right) \]
            5. lower-log.f6462.7

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

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

          Alternative 10: 68.2% 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.f6462.7

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

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

          Alternative 11: 61.2% accurate, 1.4× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -1 \cdot 10^{+21} \lor \neg \left(a - 0.5 \leq 40000000\right):\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot y\right)\right) - t\\ \end{array} \end{array} \]
          (FPCore (x y z t a)
           :precision binary64
           (if (or (<= (- a 0.5) -1e+21) (not (<= (- a 0.5) 40000000.0)))
             (* (log t) a)
             (- (fma -0.5 (log t) (log (* z y))) t)))
          double code(double x, double y, double z, double t, double a) {
          	double tmp;
          	if (((a - 0.5) <= -1e+21) || !((a - 0.5) <= 40000000.0)) {
          		tmp = log(t) * a;
          	} else {
          		tmp = fma(-0.5, log(t), log((z * y))) - t;
          	}
          	return tmp;
          }
          
          function code(x, y, z, t, a)
          	tmp = 0.0
          	if ((Float64(a - 0.5) <= -1e+21) || !(Float64(a - 0.5) <= 40000000.0))
          		tmp = Float64(log(t) * a);
          	else
          		tmp = Float64(fma(-0.5, log(t), log(Float64(z * y))) - t);
          	end
          	return tmp
          end
          
          code[x_, y_, z_, t_, a_] := If[Or[LessEqual[N[(a - 0.5), $MachinePrecision], -1e+21], N[Not[LessEqual[N[(a - 0.5), $MachinePrecision], 40000000.0]], $MachinePrecision]], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision], N[(N[(-0.5 * N[Log[t], $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          \mathbf{if}\;a - 0.5 \leq -1 \cdot 10^{+21} \lor \neg \left(a - 0.5 \leq 40000000\right):\\
          \;\;\;\;\log t \cdot a\\
          
          \mathbf{else}:\\
          \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot y\right)\right) - t\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if (-.f64 a #s(literal 1/2 binary64)) < -1e21 or 4e7 < (-.f64 a #s(literal 1/2 binary64))

            1. Initial program 99.7%

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

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

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

                \[\leadsto \color{blue}{\log t \cdot a} \]
              3. lower-log.f6481.3

                \[\leadsto \color{blue}{\log t} \cdot a \]
            5. Applied rewrites81.3%

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

            if -1e21 < (-.f64 a #s(literal 1/2 binary64)) < 4e7

            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

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

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

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

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

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

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

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

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

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

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

                \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \color{blue}{\left(y + x\right)}\right) + \left(\log z - t\right) \]
              14. lower--.f6499.5

                \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \left(y + x\right)\right) + \color{blue}{\left(\log z - t\right)} \]
            4. Applied rewrites99.5%

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

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

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

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

                \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(y + x\right)\right) + \log z\right) - t} \]
            6. Applied rewrites73.8%

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

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

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

                \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
              3. lower-*.f6441.5

                \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \color{blue}{\left(z \cdot y\right)}\right) - t \]
            9. Applied rewrites41.5%

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

              \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{-1}{2}}, \log t, \log \left(z \cdot y\right)\right) - t \]
            11. Step-by-step derivation
              1. Applied rewrites40.2%

                \[\leadsto \mathsf{fma}\left(\color{blue}{-0.5}, \log t, \log \left(z \cdot y\right)\right) - t \]
            12. Recombined 2 regimes into one program.
            13. Final simplification59.3%

              \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -1 \cdot 10^{+21} \lor \neg \left(a - 0.5 \leq 40000000\right):\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot y\right)\right) - t\\ \end{array} \]
            14. Add Preprocessing

            Alternative 12: 61.9% accurate, 2.7× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a \leq -7 \cdot 10^{+65} \lor \neg \left(a \leq 110000000000\right):\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
            (FPCore (x y z t a)
             :precision binary64
             (if (or (<= a -7e+65) (not (<= a 110000000000.0))) (* (log t) a) (- t)))
            double code(double x, double y, double z, double t, double a) {
            	double tmp;
            	if ((a <= -7e+65) || !(a <= 110000000000.0)) {
            		tmp = log(t) * a;
            	} else {
            		tmp = -t;
            	}
            	return tmp;
            }
            
            real(8) function code(x, y, z, t, a)
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                real(8), intent (in) :: z
                real(8), intent (in) :: t
                real(8), intent (in) :: a
                real(8) :: tmp
                if ((a <= (-7d+65)) .or. (.not. (a <= 110000000000.0d0))) then
                    tmp = log(t) * a
                else
                    tmp = -t
                end if
                code = tmp
            end function
            
            public static double code(double x, double y, double z, double t, double a) {
            	double tmp;
            	if ((a <= -7e+65) || !(a <= 110000000000.0)) {
            		tmp = Math.log(t) * a;
            	} else {
            		tmp = -t;
            	}
            	return tmp;
            }
            
            def code(x, y, z, t, a):
            	tmp = 0
            	if (a <= -7e+65) or not (a <= 110000000000.0):
            		tmp = math.log(t) * a
            	else:
            		tmp = -t
            	return tmp
            
            function code(x, y, z, t, a)
            	tmp = 0.0
            	if ((a <= -7e+65) || !(a <= 110000000000.0))
            		tmp = Float64(log(t) * a);
            	else
            		tmp = Float64(-t);
            	end
            	return tmp
            end
            
            function tmp_2 = code(x, y, z, t, a)
            	tmp = 0.0;
            	if ((a <= -7e+65) || ~((a <= 110000000000.0)))
            		tmp = log(t) * a;
            	else
            		tmp = -t;
            	end
            	tmp_2 = tmp;
            end
            
            code[x_, y_, z_, t_, a_] := If[Or[LessEqual[a, -7e+65], N[Not[LessEqual[a, 110000000000.0]], $MachinePrecision]], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision], (-t)]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;a \leq -7 \cdot 10^{+65} \lor \neg \left(a \leq 110000000000\right):\\
            \;\;\;\;\log t \cdot a\\
            
            \mathbf{else}:\\
            \;\;\;\;-t\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if a < -7.0000000000000002e65 or 1.1e11 < a

              1. Initial program 99.7%

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

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

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

                  \[\leadsto \color{blue}{\log t \cdot a} \]
                3. lower-log.f6483.9

                  \[\leadsto \color{blue}{\log t} \cdot a \]
              5. Applied rewrites83.9%

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

              if -7.0000000000000002e65 < a < 1.1e11

              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.f6448.9

                  \[\leadsto \color{blue}{-t} \]
              5. Applied rewrites48.9%

                \[\leadsto \color{blue}{-t} \]
            3. Recombined 2 regimes into one program.
            4. Final simplification63.9%

              \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -7 \cdot 10^{+65} \lor \neg \left(a \leq 110000000000\right):\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \]
            5. Add Preprocessing

            Alternative 13: 37.4% accurate, 107.0× speedup?

            \[\begin{array}{l} \\ -t \end{array} \]
            (FPCore (x y z t a) :precision binary64 (- t))
            double code(double x, double y, double z, double t, double a) {
            	return -t;
            }
            
            real(8) function code(x, y, z, t, a)
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                real(8), intent (in) :: z
                real(8), intent (in) :: t
                real(8), intent (in) :: a
                code = -t
            end function
            
            public static double code(double x, double y, double z, double t, double a) {
            	return -t;
            }
            
            def code(x, y, z, t, a):
            	return -t
            
            function code(x, y, z, t, a)
            	return Float64(-t)
            end
            
            function tmp = code(x, y, z, t, a)
            	tmp = -t;
            end
            
            code[x_, y_, z_, t_, a_] := (-t)
            
            \begin{array}{l}
            
            \\
            -t
            \end{array}
            
            Derivation
            1. Initial program 99.6%

              \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
            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.f6435.4

                \[\leadsto \color{blue}{-t} \]
            5. Applied rewrites35.4%

              \[\leadsto \color{blue}{-t} \]
            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 2024329 
            (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))))