Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 12.9s
Alternatives: 11
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 11 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: 82.7% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(a - 0.5\right) \cdot \log t\\ t_2 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + t\_1\\ \mathbf{if}\;t\_2 \leq -1000000000000 \lor \neg \left(t\_2 \leq 700\right):\\ \;\;\;\;\left(-t\right) + t\_1\\ \mathbf{else}:\\ \;\;\;\;\log \left(\left(z \cdot y\right) \cdot \sqrt{{t}^{-1}}\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (* (- a 0.5) (log t)))
        (t_2 (+ (- (+ (log (+ x y)) (log z)) t) t_1)))
   (if (or (<= t_2 -1000000000000.0) (not (<= t_2 700.0)))
     (+ (- t) t_1)
     (- (log (* (* z y) (sqrt (pow t -1.0)))) t))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = (a - 0.5) * log(t);
	double t_2 = ((log((x + y)) + log(z)) - t) + t_1;
	double tmp;
	if ((t_2 <= -1000000000000.0) || !(t_2 <= 700.0)) {
		tmp = -t + t_1;
	} else {
		tmp = log(((z * y) * sqrt(pow(t, -1.0)))) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: t_1
    real(8) :: t_2
    real(8) :: tmp
    t_1 = (a - 0.5d0) * log(t)
    t_2 = ((log((x + y)) + log(z)) - t) + t_1
    if ((t_2 <= (-1000000000000.0d0)) .or. (.not. (t_2 <= 700.0d0))) then
        tmp = -t + t_1
    else
        tmp = log(((z * y) * sqrt((t ** (-1.0d0))))) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = (a - 0.5) * Math.log(t);
	double t_2 = ((Math.log((x + y)) + Math.log(z)) - t) + t_1;
	double tmp;
	if ((t_2 <= -1000000000000.0) || !(t_2 <= 700.0)) {
		tmp = -t + t_1;
	} else {
		tmp = Math.log(((z * y) * Math.sqrt(Math.pow(t, -1.0)))) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = (a - 0.5) * math.log(t)
	t_2 = ((math.log((x + y)) + math.log(z)) - t) + t_1
	tmp = 0
	if (t_2 <= -1000000000000.0) or not (t_2 <= 700.0):
		tmp = -t + t_1
	else:
		tmp = math.log(((z * y) * math.sqrt(math.pow(t, -1.0)))) - t
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(Float64(a - 0.5) * log(t))
	t_2 = Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + t_1)
	tmp = 0.0
	if ((t_2 <= -1000000000000.0) || !(t_2 <= 700.0))
		tmp = Float64(Float64(-t) + t_1);
	else
		tmp = Float64(log(Float64(Float64(z * y) * sqrt((t ^ -1.0)))) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = (a - 0.5) * log(t);
	t_2 = ((log((x + y)) + log(z)) - t) + t_1;
	tmp = 0.0;
	if ((t_2 <= -1000000000000.0) || ~((t_2 <= 700.0)))
		tmp = -t + t_1;
	else
		tmp = log(((z * y) * sqrt((t ^ -1.0)))) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + t$95$1), $MachinePrecision]}, If[Or[LessEqual[t$95$2, -1000000000000.0], N[Not[LessEqual[t$95$2, 700.0]], $MachinePrecision]], N[((-t) + t$95$1), $MachinePrecision], N[(N[Log[N[(N[(z * y), $MachinePrecision] * N[Sqrt[N[Power[t, -1.0], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(a - 0.5\right) \cdot \log t\\
t_2 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + t\_1\\
\mathbf{if}\;t\_2 \leq -1000000000000 \lor \neg \left(t\_2 \leq 700\right):\\
\;\;\;\;\left(-t\right) + t\_1\\

\mathbf{else}:\\
\;\;\;\;\log \left(\left(z \cdot y\right) \cdot \sqrt{{t}^{-1}}\right) - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 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))) < -1e12 or 700 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t)))

    1. Initial program 99.8%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, \color{blue}{y - x}, x \cdot x\right)\right)\right) + \log z\right) - t\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
      16. lower-*.f6431.1

        \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, \color{blue}{x \cdot x}\right)\right)\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    4. Applied rewrites31.1%

      \[\leadsto \left(\left(\color{blue}{\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, x \cdot x\right)\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    5. Taylor expanded in y around inf

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(\color{blue}{-\log y}, -2, t\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
      14. lower-log.f6471.3

        \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\color{blue}{\log y}, -2, t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    7. Applied rewrites71.3%

      \[\leadsto \color{blue}{\left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\log y, -2, t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    8. Taylor expanded in t around inf

      \[\leadsto -1 \cdot \color{blue}{t} + \left(a - \frac{1}{2}\right) \cdot \log t \]
    9. Step-by-step derivation
      1. Applied rewrites92.7%

        \[\leadsto \left(-t\right) + \left(a - 0.5\right) \cdot \log t \]

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

      1. Initial program 98.9%

        \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
      2. Add Preprocessing
      3. Taylor expanded in 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.f6447.6

          \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
      5. Applied rewrites47.6%

        \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
      6. Step-by-step derivation
        1. Applied rewrites40.6%

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

          \[\leadsto \log \left(\sqrt{\frac{1}{t}} \cdot \left(y \cdot z\right)\right) - t \]
        3. Step-by-step derivation
          1. Applied rewrites44.2%

            \[\leadsto \log \left(\left(z \cdot y\right) \cdot \sqrt{\frac{1}{t}}\right) - t \]
        4. Recombined 2 regimes into one program.
        5. Final simplification84.4%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq -1000000000000 \lor \neg \left(\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq 700\right):\\ \;\;\;\;\left(-t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\log \left(\left(z \cdot y\right) \cdot \sqrt{{t}^{-1}}\right) - t\\ \end{array} \]
        6. Add Preprocessing

        Alternative 3: 83.3% accurate, 0.4× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(a - 0.5\right) \cdot \log t\\ t_2 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + t\_1\\ \mathbf{if}\;t\_2 \leq -1000000000000 \lor \neg \left(t\_2 \leq 940\right):\\ \;\;\;\;\left(-t\right) + t\_1\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, -0.5, \log \left(z \cdot y\right) - t\right)\\ \end{array} \end{array} \]
        (FPCore (x y z t a)
         :precision binary64
         (let* ((t_1 (* (- a 0.5) (log t)))
                (t_2 (+ (- (+ (log (+ x y)) (log z)) t) t_1)))
           (if (or (<= t_2 -1000000000000.0) (not (<= t_2 940.0)))
             (+ (- t) t_1)
             (fma (log t) -0.5 (- (log (* z y)) t)))))
        double code(double x, double y, double z, double t, double a) {
        	double t_1 = (a - 0.5) * log(t);
        	double t_2 = ((log((x + y)) + log(z)) - t) + t_1;
        	double tmp;
        	if ((t_2 <= -1000000000000.0) || !(t_2 <= 940.0)) {
        		tmp = -t + t_1;
        	} else {
        		tmp = fma(log(t), -0.5, (log((z * y)) - t));
        	}
        	return tmp;
        }
        
        function code(x, y, z, t, a)
        	t_1 = Float64(Float64(a - 0.5) * log(t))
        	t_2 = Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + t_1)
        	tmp = 0.0
        	if ((t_2 <= -1000000000000.0) || !(t_2 <= 940.0))
        		tmp = Float64(Float64(-t) + t_1);
        	else
        		tmp = fma(log(t), -0.5, Float64(log(Float64(z * y)) - t));
        	end
        	return tmp
        end
        
        code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + t$95$1), $MachinePrecision]}, If[Or[LessEqual[t$95$2, -1000000000000.0], N[Not[LessEqual[t$95$2, 940.0]], $MachinePrecision]], N[((-t) + t$95$1), $MachinePrecision], N[(N[Log[t], $MachinePrecision] * -0.5 + N[(N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]]]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        t_1 := \left(a - 0.5\right) \cdot \log t\\
        t_2 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + t\_1\\
        \mathbf{if}\;t\_2 \leq -1000000000000 \lor \neg \left(t\_2 \leq 940\right):\\
        \;\;\;\;\left(-t\right) + t\_1\\
        
        \mathbf{else}:\\
        \;\;\;\;\mathsf{fma}\left(\log t, -0.5, \log \left(z \cdot y\right) - t\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 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))) < -1e12 or 940 < (+.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 99.8%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

              \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, \color{blue}{y - x}, x \cdot x\right)\right)\right) + \log z\right) - t\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
            16. lower-*.f6430.8

              \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, \color{blue}{x \cdot x}\right)\right)\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
          4. Applied rewrites30.8%

            \[\leadsto \left(\left(\color{blue}{\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, x \cdot x\right)\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
          5. Taylor expanded in y around inf

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

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

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

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

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

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

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

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

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

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

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

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

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

              \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(\color{blue}{-\log y}, -2, t\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
            14. lower-log.f6472.1

              \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\color{blue}{\log y}, -2, t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
          7. Applied rewrites72.1%

            \[\leadsto \color{blue}{\left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\log y, -2, t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
          8. Taylor expanded in t around inf

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

              \[\leadsto \left(-t\right) + \left(a - 0.5\right) \cdot \log t \]

            if -1e12 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 940

            1. Initial program 99.0%

              \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
            2. Add Preprocessing
            3. 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.f6449.3

                \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
            5. Applied rewrites49.3%

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

              \[\leadsto \mathsf{fma}\left(\frac{-1}{2}, \log t, \log z\right) + \left(\log \color{blue}{y} - t\right) \]
            7. Step-by-step derivation
              1. Applied rewrites49.3%

                \[\leadsto \mathsf{fma}\left(-0.5, \log t, \log z\right) + \left(\log \color{blue}{y} - t\right) \]
              2. Step-by-step derivation
                1. Applied rewrites42.8%

                  \[\leadsto \mathsf{fma}\left(\log t, \color{blue}{-0.5}, \log \left(z \cdot y\right) - t\right) \]
              3. Recombined 2 regimes into one program.
              4. Final simplification85.2%

                \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq -1000000000000 \lor \neg \left(\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq 940\right):\\ \;\;\;\;\left(-t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, -0.5, \log \left(z \cdot y\right) - t\right)\\ \end{array} \]
              5. Add Preprocessing

              Alternative 4: 93.2% accurate, 0.5× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 662\right):\\ \;\;\;\;\left(-t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)\\ \end{array} \end{array} \]
              (FPCore (x y z t a)
               :precision binary64
               (let* ((t_1 (+ (log (+ x y)) (log z))))
                 (if (or (<= t_1 -750.0) (not (<= t_1 662.0)))
                   (+ (- t) (* (- a 0.5) (log t)))
                   (fma (- a 0.5) (log t) (- (log (* z (+ y x))) t)))))
              double code(double x, double y, double z, double t, double a) {
              	double t_1 = log((x + y)) + log(z);
              	double tmp;
              	if ((t_1 <= -750.0) || !(t_1 <= 662.0)) {
              		tmp = -t + ((a - 0.5) * log(t));
              	} else {
              		tmp = fma((a - 0.5), log(t), (log((z * (y + x))) - t));
              	}
              	return tmp;
              }
              
              function code(x, y, z, t, a)
              	t_1 = Float64(log(Float64(x + y)) + log(z))
              	tmp = 0.0
              	if ((t_1 <= -750.0) || !(t_1 <= 662.0))
              		tmp = Float64(Float64(-t) + Float64(Float64(a - 0.5) * log(t)));
              	else
              		tmp = fma(Float64(a - 0.5), log(t), Float64(log(Float64(z * Float64(y + x))) - t));
              	end
              	return tmp
              end
              
              code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$1, -750.0], N[Not[LessEqual[t$95$1, 662.0]], $MachinePrecision]], N[((-t) + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[(N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              t_1 := \log \left(x + y\right) + \log z\\
              \mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 662\right):\\
              \;\;\;\;\left(-t\right) + \left(a - 0.5\right) \cdot \log t\\
              
              \mathbf{else}:\\
              \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750 or 662 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

                1. Initial program 99.7%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, \color{blue}{y - x}, x \cdot x\right)\right)\right) + \log z\right) - t\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
                  16. lower-*.f648.5

                    \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, \color{blue}{x \cdot x}\right)\right)\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                4. Applied rewrites8.5%

                  \[\leadsto \left(\left(\color{blue}{\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, x \cdot x\right)\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                5. Taylor expanded in y around inf

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

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

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

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(\color{blue}{-\log y}, -2, t\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
                  14. lower-log.f6468.8

                    \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\color{blue}{\log y}, -2, t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
                7. Applied rewrites68.8%

                  \[\leadsto \color{blue}{\left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\log y, -2, t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
                8. Taylor expanded in t around inf

                  \[\leadsto -1 \cdot \color{blue}{t} + \left(a - \frac{1}{2}\right) \cdot \log t \]
                9. Step-by-step derivation
                  1. Applied rewrites84.4%

                    \[\leadsto \left(-t\right) + \left(a - 0.5\right) \cdot \log t \]

                  if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 662

                  1. Initial program 99.6%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)} \]
                10. Recombined 2 regimes into one program.
                11. Final simplification95.2%

                  \[\leadsto \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq -750 \lor \neg \left(\log \left(x + y\right) + \log z \leq 662\right):\\ \;\;\;\;\left(-t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)\\ \end{array} \]
                12. Add Preprocessing

                Alternative 5: 67.7% accurate, 0.5× speedup?

                \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 662\right):\\ \;\;\;\;\left(-t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(-0.5 + a, \log t, \log \left(z \cdot y\right) - t\right)\\ \end{array} \end{array} \]
                (FPCore (x y z t a)
                 :precision binary64
                 (let* ((t_1 (+ (log (+ x y)) (log z))))
                   (if (or (<= t_1 -750.0) (not (<= t_1 662.0)))
                     (+ (- t) (* (- a 0.5) (log t)))
                     (fma (+ -0.5 a) (log t) (- (log (* z y)) t)))))
                double code(double x, double y, double z, double t, double a) {
                	double t_1 = log((x + y)) + log(z);
                	double tmp;
                	if ((t_1 <= -750.0) || !(t_1 <= 662.0)) {
                		tmp = -t + ((a - 0.5) * log(t));
                	} else {
                		tmp = fma((-0.5 + a), log(t), (log((z * y)) - t));
                	}
                	return tmp;
                }
                
                function code(x, y, z, t, a)
                	t_1 = Float64(log(Float64(x + y)) + log(z))
                	tmp = 0.0
                	if ((t_1 <= -750.0) || !(t_1 <= 662.0))
                		tmp = Float64(Float64(-t) + Float64(Float64(a - 0.5) * log(t)));
                	else
                		tmp = fma(Float64(-0.5 + a), log(t), Float64(log(Float64(z * y)) - t));
                	end
                	return tmp
                end
                
                code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$1, -750.0], N[Not[LessEqual[t$95$1, 662.0]], $MachinePrecision]], N[((-t) + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(-0.5 + a), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[(N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]]]
                
                \begin{array}{l}
                
                \\
                \begin{array}{l}
                t_1 := \log \left(x + y\right) + \log z\\
                \mathbf{if}\;t\_1 \leq -750 \lor \neg \left(t\_1 \leq 662\right):\\
                \;\;\;\;\left(-t\right) + \left(a - 0.5\right) \cdot \log t\\
                
                \mathbf{else}:\\
                \;\;\;\;\mathsf{fma}\left(-0.5 + a, \log t, \log \left(z \cdot y\right) - t\right)\\
                
                
                \end{array}
                \end{array}
                
                Derivation
                1. Split input into 2 regimes
                2. if (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < -750 or 662 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

                  1. Initial program 99.7%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                      \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, \color{blue}{y - x}, x \cdot x\right)\right)\right) + \log z\right) - t\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
                    16. lower-*.f648.5

                      \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, \color{blue}{x \cdot x}\right)\right)\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                  4. Applied rewrites8.5%

                    \[\leadsto \left(\left(\color{blue}{\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, x \cdot x\right)\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                  5. Taylor expanded in y around inf

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

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

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

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

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

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

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

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

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

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

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

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

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

                      \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(\color{blue}{-\log y}, -2, t\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
                    14. lower-log.f6468.8

                      \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\color{blue}{\log y}, -2, t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
                  7. Applied rewrites68.8%

                    \[\leadsto \color{blue}{\left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\log y, -2, t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
                  8. Taylor expanded in t around inf

                    \[\leadsto -1 \cdot \color{blue}{t} + \left(a - \frac{1}{2}\right) \cdot \log t \]
                  9. Step-by-step derivation
                    1. Applied rewrites84.4%

                      \[\leadsto \left(-t\right) + \left(a - 0.5\right) \cdot \log t \]

                    if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 662

                    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.f6466.6

                        \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
                    5. Applied rewrites66.6%

                      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
                    6. Step-by-step derivation
                      1. Applied rewrites61.9%

                        \[\leadsto \mathsf{fma}\left(-0.5 + a, \color{blue}{\log t}, \log \left(z \cdot y\right) - t\right) \]
                    7. Recombined 2 regimes into one program.
                    8. Final simplification68.2%

                      \[\leadsto \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq -750 \lor \neg \left(\log \left(x + y\right) + \log z \leq 662\right):\\ \;\;\;\;\left(-t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(-0.5 + a, \log t, \log \left(z \cdot y\right) - t\right)\\ \end{array} \]
                    9. Add Preprocessing

                    Alternative 6: 80.0% accurate, 1.0× speedup?

                    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 460:\\ \;\;\;\;\log z + \mathsf{fma}\left(\log t, a - 0.5, \log y\right)\\ \mathbf{else}:\\ \;\;\;\;\left(-t\right) + \left(a - 0.5\right) \cdot \log t\\ \end{array} \end{array} \]
                    (FPCore (x y z t a)
                     :precision binary64
                     (if (<= t 460.0)
                       (+ (log z) (fma (log t) (- a 0.5) (log y)))
                       (+ (- t) (* (- a 0.5) (log t)))))
                    double code(double x, double y, double z, double t, double a) {
                    	double tmp;
                    	if (t <= 460.0) {
                    		tmp = log(z) + fma(log(t), (a - 0.5), log(y));
                    	} else {
                    		tmp = -t + ((a - 0.5) * log(t));
                    	}
                    	return tmp;
                    }
                    
                    function code(x, y, z, t, a)
                    	tmp = 0.0
                    	if (t <= 460.0)
                    		tmp = Float64(log(z) + fma(log(t), Float64(a - 0.5), log(y)));
                    	else
                    		tmp = Float64(Float64(-t) + Float64(Float64(a - 0.5) * log(t)));
                    	end
                    	return tmp
                    end
                    
                    code[x_, y_, z_, t_, a_] := If[LessEqual[t, 460.0], N[(N[Log[z], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[((-t) + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
                    
                    \begin{array}{l}
                    
                    \\
                    \begin{array}{l}
                    \mathbf{if}\;t \leq 460:\\
                    \;\;\;\;\log z + \mathsf{fma}\left(\log t, a - 0.5, \log y\right)\\
                    
                    \mathbf{else}:\\
                    \;\;\;\;\left(-t\right) + \left(a - 0.5\right) \cdot \log t\\
                    
                    
                    \end{array}
                    \end{array}
                    
                    Derivation
                    1. Split input into 2 regimes
                    2. if t < 460

                      1. Initial program 99.3%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                          \[\leadsto \mathsf{fma}\left(\frac{-1}{2} + a, \log t, \log z\right) + \color{blue}{\left(\log y - t\right)} \]
                        16. lower-log.f6459.7

                          \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
                      5. Applied rewrites59.7%

                        \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
                      6. Step-by-step derivation
                        1. Applied rewrites59.8%

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

                          \[\leadsto \log z + \left(\log y + \color{blue}{\log t \cdot \left(a - \frac{1}{2}\right)}\right) \]
                        3. Step-by-step derivation
                          1. Applied rewrites59.8%

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

                          if 460 < 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-log.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                              \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, \color{blue}{y - x}, x \cdot x\right)\right)\right) + \log z\right) - t\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
                            16. lower-*.f6430.1

                              \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, \color{blue}{x \cdot x}\right)\right)\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                          4. Applied rewrites30.1%

                            \[\leadsto \left(\left(\color{blue}{\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, x \cdot x\right)\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                          5. Taylor expanded in y around inf

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

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

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

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

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

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

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

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

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

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

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

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

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

                              \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(\color{blue}{-\log y}, -2, t\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
                            14. lower-log.f6474.2

                              \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\color{blue}{\log y}, -2, t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
                          7. Applied rewrites74.2%

                            \[\leadsto \color{blue}{\left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\log y, -2, t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
                          8. Taylor expanded in t around inf

                            \[\leadsto -1 \cdot \color{blue}{t} + \left(a - \frac{1}{2}\right) \cdot \log t \]
                          9. Step-by-step derivation
                            1. Applied rewrites99.9%

                              \[\leadsto \left(-t\right) + \left(a - 0.5\right) \cdot \log t \]
                          10. Recombined 2 regimes into one program.
                          11. Add Preprocessing

                          Alternative 7: 68.3% accurate, 1.0× speedup?

                          \[\begin{array}{l} \\ \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right) \end{array} \]
                          (FPCore (x y z t a)
                           :precision binary64
                           (+ (fma (+ -0.5 a) (log t) (log z)) (- (log y) t)))
                          double code(double x, double y, double z, double t, double a) {
                          	return fma((-0.5 + a), log(t), log(z)) + (log(y) - t);
                          }
                          
                          function code(x, y, z, t, a)
                          	return Float64(fma(Float64(-0.5 + a), log(t), log(z)) + Float64(log(y) - t))
                          end
                          
                          code[x_, y_, z_, t_, a_] := N[(N[(N[(-0.5 + a), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] + N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]
                          
                          \begin{array}{l}
                          
                          \\
                          \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)
                          \end{array}
                          
                          Derivation
                          1. Initial program 99.6%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                              \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
                          5. Applied rewrites67.2%

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

                          Alternative 8: 68.3% accurate, 1.0× speedup?

                          \[\begin{array}{l} \\ \log z + \mathsf{fma}\left(\log t, -0.5 + a, \log y - t\right) \end{array} \]
                          (FPCore (x y z t a)
                           :precision binary64
                           (+ (log z) (fma (log t) (+ -0.5 a) (- (log y) t))))
                          double code(double x, double y, double z, double t, double a) {
                          	return log(z) + fma(log(t), (-0.5 + a), (log(y) - t));
                          }
                          
                          function code(x, y, z, t, a)
                          	return Float64(log(z) + fma(log(t), Float64(-0.5 + a), Float64(log(y) - t)))
                          end
                          
                          code[x_, y_, z_, t_, a_] := N[(N[Log[z], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(-0.5 + a), $MachinePrecision] + N[(N[Log[y], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                          
                          \begin{array}{l}
                          
                          \\
                          \log z + \mathsf{fma}\left(\log t, -0.5 + a, \log y - t\right)
                          \end{array}
                          
                          Derivation
                          1. Initial program 99.6%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                              \[\leadsto \mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\color{blue}{\log y} - t\right) \]
                          5. Applied rewrites67.2%

                            \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5 + a, \log t, \log z\right) + \left(\log y - t\right)} \]
                          6. Step-by-step derivation
                            1. Applied rewrites67.2%

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

                            Alternative 9: 76.8% accurate, 2.8× speedup?

                            \[\begin{array}{l} \\ \left(-t\right) + \left(a - 0.5\right) \cdot \log t \end{array} \]
                            (FPCore (x y z t a) :precision binary64 (+ (- t) (* (- a 0.5) (log t))))
                            double code(double x, double y, double z, double t, double a) {
                            	return -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 = -t + ((a - 0.5d0) * log(t))
                            end function
                            
                            public static double code(double x, double y, double z, double t, double a) {
                            	return -t + ((a - 0.5) * Math.log(t));
                            }
                            
                            def code(x, y, z, t, a):
                            	return -t + ((a - 0.5) * math.log(t))
                            
                            function code(x, y, z, t, a)
                            	return Float64(Float64(-t) + Float64(Float64(a - 0.5) * log(t)))
                            end
                            
                            function tmp = code(x, y, z, t, a)
                            	tmp = -t + ((a - 0.5) * log(t));
                            end
                            
                            code[x_, y_, z_, t_, a_] := N[((-t) + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                            
                            \begin{array}{l}
                            
                            \\
                            \left(-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. Step-by-step derivation
                              1. lift-log.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                                \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, \color{blue}{y - x}, x \cdot x\right)\right)\right) + \log z\right) - t\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
                              16. lower-*.f6432.2

                                \[\leadsto \left(\left(\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, \color{blue}{x \cdot x}\right)\right)\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                            4. Applied rewrites32.2%

                              \[\leadsto \left(\left(\color{blue}{\left(\log \left({y}^{3} + {x}^{3}\right) - \log \left(\mathsf{fma}\left(y, y - x, x \cdot x\right)\right)\right)} + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
                            5. Taylor expanded in y around inf

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

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

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

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

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

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

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

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

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

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

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

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

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

                                \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(\color{blue}{-\log y}, -2, t\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
                              14. lower-log.f6467.2

                                \[\leadsto \left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\color{blue}{\log y}, -2, t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
                            7. Applied rewrites67.2%

                              \[\leadsto \color{blue}{\left(\mathsf{fma}\left(-\log y, -3, \log z\right) - \mathsf{fma}\left(-\log y, -2, t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
                            8. Taylor expanded in t around inf

                              \[\leadsto -1 \cdot \color{blue}{t} + \left(a - \frac{1}{2}\right) \cdot \log t \]
                            9. Step-by-step derivation
                              1. Applied rewrites79.2%

                                \[\leadsto \left(-t\right) + \left(a - 0.5\right) \cdot \log t \]
                              2. Add Preprocessing

                              Alternative 10: 62.4% accurate, 2.9× speedup?

                              \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 8.5 \cdot 10^{+29}:\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
                              (FPCore (x y z t a)
                               :precision binary64
                               (if (<= t 8.5e+29) (* (log t) a) (- t)))
                              double code(double x, double y, double z, double t, double a) {
                              	double tmp;
                              	if (t <= 8.5e+29) {
                              		tmp = log(t) * a;
                              	} else {
                              		tmp = -t;
                              	}
                              	return tmp;
                              }
                              
                              real(8) function code(x, y, z, t, a)
                                  real(8), intent (in) :: x
                                  real(8), intent (in) :: y
                                  real(8), intent (in) :: z
                                  real(8), intent (in) :: t
                                  real(8), intent (in) :: a
                                  real(8) :: tmp
                                  if (t <= 8.5d+29) then
                                      tmp = log(t) * a
                                  else
                                      tmp = -t
                                  end if
                                  code = tmp
                              end function
                              
                              public static double code(double x, double y, double z, double t, double a) {
                              	double tmp;
                              	if (t <= 8.5e+29) {
                              		tmp = Math.log(t) * a;
                              	} else {
                              		tmp = -t;
                              	}
                              	return tmp;
                              }
                              
                              def code(x, y, z, t, a):
                              	tmp = 0
                              	if t <= 8.5e+29:
                              		tmp = math.log(t) * a
                              	else:
                              		tmp = -t
                              	return tmp
                              
                              function code(x, y, z, t, a)
                              	tmp = 0.0
                              	if (t <= 8.5e+29)
                              		tmp = Float64(log(t) * a);
                              	else
                              		tmp = Float64(-t);
                              	end
                              	return tmp
                              end
                              
                              function tmp_2 = code(x, y, z, t, a)
                              	tmp = 0.0;
                              	if (t <= 8.5e+29)
                              		tmp = log(t) * a;
                              	else
                              		tmp = -t;
                              	end
                              	tmp_2 = tmp;
                              end
                              
                              code[x_, y_, z_, t_, a_] := If[LessEqual[t, 8.5e+29], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision], (-t)]
                              
                              \begin{array}{l}
                              
                              \\
                              \begin{array}{l}
                              \mathbf{if}\;t \leq 8.5 \cdot 10^{+29}:\\
                              \;\;\;\;\log t \cdot a\\
                              
                              \mathbf{else}:\\
                              \;\;\;\;-t\\
                              
                              
                              \end{array}
                              \end{array}
                              
                              Derivation
                              1. Split input into 2 regimes
                              2. if t < 8.5000000000000006e29

                                1. Initial program 99.3%

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

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

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

                                    \[\leadsto \color{blue}{\log t \cdot a} \]
                                  3. lower-log.f6453.8

                                    \[\leadsto \color{blue}{\log t} \cdot a \]
                                5. Applied rewrites53.8%

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

                                if 8.5000000000000006e29 < 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.f6473.4

                                    \[\leadsto \color{blue}{-t} \]
                                5. Applied rewrites73.4%

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

                              Alternative 11: 37.9% 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.f6437.5

                                  \[\leadsto \color{blue}{-t} \]
                              5. Applied rewrites37.5%

                                \[\leadsto \color{blue}{-t} \]
                              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 2024343 
                              (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))))