Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 8.8s
Alternatives: 15
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));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(x, y, z, t, a)
use fmin_fmax_functions
    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 15 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));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(x, y, z, t, a)
use fmin_fmax_functions
    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?

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

\\
\mathsf{fma}\left(a - 0.5, \log t, \left(\log \left(x + y\right) + \log z\right) - t\right)
\end{array}
Derivation
  1. Initial program 99.5%

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

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

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

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

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

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

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

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

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

      \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - t\right) \]
    11. lower-+.f6475.3

      \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - t\right) \]
  4. Applied rewrites75.3%

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

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

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

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

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

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

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

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

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

Alternative 2: 79.1% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(a - 0.5\right) \cdot \log t\\ t_2 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + t\_1\\ \mathbf{if}\;t\_2 \leq -200000000:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, -t\right)\\ \mathbf{elif}\;t\_2 \leq 860:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + \left(-t\right)\right) + t\_1\\ \end{array} \end{array} \]
(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 (<= t_2 -200000000.0)
     (fma (- a 0.5) (log t) (- t))
     (if (<= t_2 860.0)
       (fma (log t) (- a 0.5) (log (* z y)))
       (+ (+ (log y) (- t)) t_1)))))
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 <= -200000000.0) {
		tmp = fma((a - 0.5), log(t), -t);
	} else if (t_2 <= 860.0) {
		tmp = fma(log(t), (a - 0.5), log((z * y)));
	} else {
		tmp = (log(y) + -t) + t_1;
	}
	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 <= -200000000.0)
		tmp = fma(Float64(a - 0.5), log(t), Float64(-t));
	elseif (t_2 <= 860.0)
		tmp = fma(log(t), Float64(a - 0.5), log(Float64(z * y)));
	else
		tmp = Float64(Float64(log(y) + Float64(-t)) + t_1);
	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[LessEqual[t$95$2, -200000000.0], N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + (-t)), $MachinePrecision], If[LessEqual[t$95$2, 860.0], N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] + (-t)), $MachinePrecision] + t$95$1), $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 -200000000:\\
\;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, -t\right)\\

\mathbf{elif}\;t\_2 \leq 860:\\
\;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < -2e8

    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. +-commutativeN/A

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - t\right) \]
    4. Applied rewrites74.1%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, -1 \cdot t\right) \]
      2. sum-logN/A

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \mathsf{neg}\left(t\right)\right) \]
      4. lower-neg.f6499.5

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, -t\right) \]
    9. Applied rewrites99.5%

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

    if -2e8 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 860

    1. Initial program 98.8%

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f6442.2

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites42.2%

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

      \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) \]
    7. Step-by-step derivation
      1. pow-to-expN/A

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(z \cdot y\right)\right) \]
      12. lower-*.f6446.1

        \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right) \]
    8. Applied rewrites46.1%

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

    if 860 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t)))

    1. Initial program 99.6%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \left(\log \left(y + x\right) + \left(\mathsf{neg}\left(t\right)\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
      2. lower-neg.f6479.5

        \[\leadsto \left(\log \left(y + x\right) + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    7. Applied rewrites79.5%

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

      \[\leadsto \left(\log \color{blue}{y} + \left(-t\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
    9. Step-by-step derivation
      1. +-commutative52.3

        \[\leadsto \left(\log y + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    10. Applied rewrites52.3%

      \[\leadsto \left(\log \color{blue}{y} + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 3: 79.0% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{if}\;t\_1 \leq -200000000:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, -t\right)\\ \mathbf{elif}\;t\_1 \leq 860:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t)))))
   (if (<= t_1 -200000000.0)
     (fma (- a 0.5) (log t) (- t))
     (if (<= t_1 860.0)
       (fma (log t) (- a 0.5) (log (* z y)))
       (- (+ (* (log t) a) (log y)) t)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
	double tmp;
	if (t_1 <= -200000000.0) {
		tmp = fma((a - 0.5), log(t), -t);
	} else if (t_1 <= 860.0) {
		tmp = fma(log(t), (a - 0.5), log((z * y)));
	} else {
		tmp = ((log(t) * a) + log(y)) - t;
	}
	return tmp;
}
function code(x, y, z, t, a)
	t_1 = Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
	tmp = 0.0
	if (t_1 <= -200000000.0)
		tmp = fma(Float64(a - 0.5), log(t), Float64(-t));
	elseif (t_1 <= 860.0)
		tmp = fma(log(t), Float64(a - 0.5), log(Float64(z * y)));
	else
		tmp = Float64(Float64(Float64(log(t) * a) + log(y)) - t);
	end
	return tmp
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, -200000000.0], N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + (-t)), $MachinePrecision], If[LessEqual[t$95$1, 860.0], N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\
\mathbf{if}\;t\_1 \leq -200000000:\\
\;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, -t\right)\\

\mathbf{elif}\;t\_1 \leq 860:\\
\;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < -2e8

    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. +-commutativeN/A

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - t\right) \]
    4. Applied rewrites74.1%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, -1 \cdot t\right) \]
      2. sum-logN/A

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \mathsf{neg}\left(t\right)\right) \]
      4. lower-neg.f6499.5

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, -t\right) \]
    9. Applied rewrites99.5%

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

    if -2e8 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 860

    1. Initial program 98.8%

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f6442.2

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites42.2%

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

      \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) \]
    7. Step-by-step derivation
      1. pow-to-expN/A

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(z \cdot y\right)\right) \]
      12. lower-*.f6446.1

        \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right) \]
    8. Applied rewrites46.1%

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

    if 860 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t)))

    1. Initial program 99.6%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Add Preprocessing
    3. Taylor expanded in 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. lower--.f64N/A

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f643.1

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites3.1%

      \[\leadsto \color{blue}{\log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t} \]
    6. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \log \left(y \cdot \left(z \cdot {t}^{\left(a - \frac{1}{2}\right)}\right)\right) - t \]
      2. pow-to-expN/A

        \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) - t \]
      3. sum-logN/A

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

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

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

        \[\leadsto \left(\left(\log z + \log \left(e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      7. pow-to-expN/A

        \[\leadsto \left(\left(\log z + \log \left({t}^{\left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      8. log-pow-revN/A

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

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

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

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

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

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

        \[\leadsto \left(\mathsf{fma}\left(\log t, a - \frac{1}{2}, \log z\right) + \log y\right) - t \]
      15. lower-log.f6460.2

        \[\leadsto \left(\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\right) - t \]
    7. Applied rewrites60.2%

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

      \[\leadsto \left(a \cdot \log t + \log y\right) - t \]
    9. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
      2. lower-*.f64N/A

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
      3. lower-log.f6452.1

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
    10. Applied rewrites52.1%

      \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 4: 64.8% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{if}\;t\_1 \leq -530 \lor \neg \left(t\_1 \leq 860\right):\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot y\right)\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t)))))
   (if (or (<= t_1 -530.0) (not (<= t_1 860.0)))
     (- (+ (* (log t) a) (log y)) t)
     (fma -0.5 (log t) (log (* z y))))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
	double tmp;
	if ((t_1 <= -530.0) || !(t_1 <= 860.0)) {
		tmp = ((log(t) * a) + log(y)) - t;
	} else {
		tmp = fma(-0.5, log(t), log((z * y)));
	}
	return tmp;
}
function code(x, y, z, t, a)
	t_1 = Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
	tmp = 0.0
	if ((t_1 <= -530.0) || !(t_1 <= 860.0))
		tmp = Float64(Float64(Float64(log(t) * a) + log(y)) - t);
	else
		tmp = fma(-0.5, log(t), log(Float64(z * y)));
	end
	return tmp
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$1, -530.0], N[Not[LessEqual[t$95$1, 860.0]], $MachinePrecision]], N[(N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(-0.5 * N[Log[t], $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\
\mathbf{if}\;t\_1 \leq -530 \lor \neg \left(t\_1 \leq 860\right):\\
\;\;\;\;\left(\log t \cdot a + \log y\right) - t\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot y\right)\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))) < -530 or 860 < (+.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. 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. lower--.f64N/A

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f6419.1

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites19.1%

      \[\leadsto \color{blue}{\log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t} \]
    6. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \log \left(y \cdot \left(z \cdot {t}^{\left(a - \frac{1}{2}\right)}\right)\right) - t \]
      2. pow-to-expN/A

        \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) - t \]
      3. sum-logN/A

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

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

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

        \[\leadsto \left(\left(\log z + \log \left(e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      7. pow-to-expN/A

        \[\leadsto \left(\left(\log z + \log \left({t}^{\left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      8. log-pow-revN/A

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

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

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

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

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

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

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

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

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

      \[\leadsto \left(a \cdot \log t + \log y\right) - t \]
    9. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
      2. lower-*.f64N/A

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
      3. lower-log.f6467.0

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
    10. Applied rewrites67.0%

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

    if -530 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 860

    1. Initial program 98.8%

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f6445.7

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites45.7%

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

      \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) \]
    7. Step-by-step derivation
      1. pow-to-expN/A

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(z \cdot y\right)\right) \]
      12. lower-*.f6448.2

        \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right) \]
    8. Applied rewrites48.2%

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\frac{-1}{2}, \log t, \log \left(z \cdot y\right)\right) \]
      13. lower-*.f6447.5

        \[\leadsto \mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot y\right)\right) \]
    11. Applied rewrites47.5%

      \[\leadsto \mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot y\right)\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification62.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq -530 \lor \neg \left(\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq 860\right):\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot y\right)\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 83.6% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{if}\;t\_1 \leq -530:\\ \;\;\;\;\log t \cdot a - t\\ \mathbf{elif}\;t\_1 \leq 860:\\ \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot y\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, -t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t)))))
   (if (<= t_1 -530.0)
     (- (* (log t) a) t)
     (if (<= t_1 860.0)
       (fma -0.5 (log t) (log (* z y)))
       (fma (- a 0.5) (log t) (- t))))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = ((log((x + y)) + log(z)) - t) + ((a - 0.5) * log(t));
	double tmp;
	if (t_1 <= -530.0) {
		tmp = (log(t) * a) - t;
	} else if (t_1 <= 860.0) {
		tmp = fma(-0.5, log(t), log((z * y)));
	} else {
		tmp = fma((a - 0.5), log(t), -t);
	}
	return tmp;
}
function code(x, y, z, t, a)
	t_1 = Float64(Float64(Float64(log(Float64(x + y)) + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
	tmp = 0.0
	if (t_1 <= -530.0)
		tmp = Float64(Float64(log(t) * a) - t);
	elseif (t_1 <= 860.0)
		tmp = fma(-0.5, log(t), log(Float64(z * y)));
	else
		tmp = fma(Float64(a - 0.5), log(t), Float64(-t));
	end
	return tmp
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(N[(N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, -530.0], N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[t$95$1, 860.0], N[(-0.5 * N[Log[t], $MachinePrecision] + N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + (-t)), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\
\mathbf{if}\;t\_1 \leq -530:\\
\;\;\;\;\log t \cdot a - t\\

\mathbf{elif}\;t\_1 \leq 860:\\
\;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot y\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, -t\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < -530

    1. Initial program 99.8%

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f6424.7

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites24.7%

      \[\leadsto \color{blue}{\log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t} \]
    6. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \log \left(y \cdot \left(z \cdot {t}^{\left(a - \frac{1}{2}\right)}\right)\right) - t \]
      2. pow-to-expN/A

        \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) - t \]
      3. sum-logN/A

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

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

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

        \[\leadsto \left(\left(\log z + \log \left(e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      7. pow-to-expN/A

        \[\leadsto \left(\left(\log z + \log \left({t}^{\left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      8. log-pow-revN/A

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

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

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

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

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

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

        \[\leadsto \left(\mathsf{fma}\left(\log t, a - \frac{1}{2}, \log z\right) + \log y\right) - t \]
      15. lower-log.f6473.7

        \[\leadsto \left(\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\right) - t \]
    7. Applied rewrites73.7%

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

      \[\leadsto a \cdot \log t - t \]
    9. Step-by-step derivation
      1. associate-+l+N/A

        \[\leadsto a \cdot \log t - t \]
      2. +-commutativeN/A

        \[\leadsto a \cdot \log t - t \]
      3. sum-logN/A

        \[\leadsto a \cdot \log t - t \]
      4. +-commutativeN/A

        \[\leadsto a \cdot \log t - t \]
      5. *-commutativeN/A

        \[\leadsto a \cdot \log t - t \]
      6. log-pow-revN/A

        \[\leadsto a \cdot \log t - t \]
      7. log-prodN/A

        \[\leadsto a \cdot \log t - t \]
      8. *-commutativeN/A

        \[\leadsto \log t \cdot a - t \]
      9. lower-*.f64N/A

        \[\leadsto \log t \cdot a - t \]
      10. lower-log.f6496.8

        \[\leadsto \log t \cdot a - t \]
    10. Applied rewrites96.8%

      \[\leadsto \log t \cdot a - t \]

    if -530 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 860

    1. Initial program 98.8%

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f6445.7

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites45.7%

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

      \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) \]
    7. Step-by-step derivation
      1. pow-to-expN/A

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(z \cdot y\right)\right) \]
      12. lower-*.f6448.2

        \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right) \]
    8. Applied rewrites48.2%

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\frac{-1}{2}, \log t, \log \left(z \cdot y\right)\right) \]
      13. lower-*.f6447.5

        \[\leadsto \mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot y\right)\right) \]
    11. Applied rewrites47.5%

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

    if 860 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t)))

    1. Initial program 99.6%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - t\right) \]
    4. Applied rewrites57.2%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, -1 \cdot t\right) \]
      2. sum-logN/A

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \mathsf{neg}\left(t\right)\right) \]
      4. lower-neg.f6478.7

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, -t\right) \]
    9. Applied rewrites78.7%

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

Alternative 6: 89.3% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -750:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \mathbf{elif}\;t\_1 \leq 700:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (log (+ x y)) (log z))))
   (if (<= t_1 -750.0)
     (- (+ (* (log t) a) (log y)) t)
     (if (<= t_1 700.0)
       (fma (- a 0.5) (log t) (- (log (* z (+ y x))) t))
       (+ (+ (log y) (- t)) (* (- a 0.5) (log 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) {
		tmp = ((log(t) * a) + log(y)) - t;
	} else if (t_1 <= 700.0) {
		tmp = fma((a - 0.5), log(t), (log((z * (y + x))) - t));
	} else {
		tmp = (log(y) + -t) + ((a - 0.5) * log(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)
		tmp = Float64(Float64(Float64(log(t) * a) + log(y)) - t);
	elseif (t_1 <= 700.0)
		tmp = fma(Float64(a - 0.5), log(t), Float64(log(Float64(z * Float64(y + x))) - t));
	else
		tmp = Float64(Float64(log(y) + Float64(-t)) + Float64(Float64(a - 0.5) * log(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[LessEqual[t$95$1, -750.0], N[(N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[t$95$1, 700.0], N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[(N[Log[N[(z * N[(y + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] + (-t)), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

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

\mathbf{elif}\;t\_1 \leq 700:\\
\;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \left(y + x\right)\right) - t\right)\\

\mathbf{else}:\\
\;\;\;\;\left(\log y + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t\\


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

    1. Initial program 99.6%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    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. lower--.f64N/A

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f642.6

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites2.6%

      \[\leadsto \color{blue}{\log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t} \]
    6. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \log \left(y \cdot \left(z \cdot {t}^{\left(a - \frac{1}{2}\right)}\right)\right) - t \]
      2. pow-to-expN/A

        \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) - t \]
      3. sum-logN/A

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

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

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

        \[\leadsto \left(\left(\log z + \log \left(e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      7. pow-to-expN/A

        \[\leadsto \left(\left(\log z + \log \left({t}^{\left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      8. log-pow-revN/A

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

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

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

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

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

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

        \[\leadsto \left(\mathsf{fma}\left(\log t, a - \frac{1}{2}, \log z\right) + \log y\right) - t \]
      15. lower-log.f6474.7

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

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

      \[\leadsto \left(a \cdot \log t + \log y\right) - t \]
    9. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
      2. lower-*.f64N/A

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
      3. lower-log.f6461.0

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
    10. Applied rewrites61.0%

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

    if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 700

    1. Initial program 99.5%

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

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

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

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

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

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

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

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

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

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

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

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

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

    1. Initial program 99.8%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \left(\log \left(y + x\right) + \left(\mathsf{neg}\left(t\right)\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
      2. lower-neg.f6478.5

        \[\leadsto \left(\log \left(y + x\right) + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    7. Applied rewrites78.5%

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

      \[\leadsto \left(\log \color{blue}{y} + \left(-t\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
    9. Step-by-step derivation
      1. +-commutative62.8

        \[\leadsto \left(\log y + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    10. Applied rewrites62.8%

      \[\leadsto \left(\log \color{blue}{y} + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 7: 63.4% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -750:\\ \;\;\;\;\left(\log t \cdot a + \log y\right) - t\\ \mathbf{elif}\;t\_1 \leq 700:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot y\right) - t\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (log (+ x y)) (log z))))
   (if (<= t_1 -750.0)
     (- (+ (* (log t) a) (log y)) t)
     (if (<= t_1 700.0)
       (fma (- a 0.5) (log t) (- (log (* z y)) t))
       (+ (+ (log y) (- t)) (* (- a 0.5) (log 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) {
		tmp = ((log(t) * a) + log(y)) - t;
	} else if (t_1 <= 700.0) {
		tmp = fma((a - 0.5), log(t), (log((z * y)) - t));
	} else {
		tmp = (log(y) + -t) + ((a - 0.5) * log(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)
		tmp = Float64(Float64(Float64(log(t) * a) + log(y)) - t);
	elseif (t_1 <= 700.0)
		tmp = fma(Float64(a - 0.5), log(t), Float64(log(Float64(z * y)) - t));
	else
		tmp = Float64(Float64(log(y) + Float64(-t)) + Float64(Float64(a - 0.5) * log(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[LessEqual[t$95$1, -750.0], N[(N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[t$95$1, 700.0], N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[(N[Log[N[(z * y), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] + (-t)), $MachinePrecision] + N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

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

\mathbf{elif}\;t\_1 \leq 700:\\
\;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot y\right) - t\right)\\

\mathbf{else}:\\
\;\;\;\;\left(\log y + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t\\


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

    1. Initial program 99.6%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    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. lower--.f64N/A

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f642.6

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites2.6%

      \[\leadsto \color{blue}{\log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t} \]
    6. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \log \left(y \cdot \left(z \cdot {t}^{\left(a - \frac{1}{2}\right)}\right)\right) - t \]
      2. pow-to-expN/A

        \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) - t \]
      3. sum-logN/A

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

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

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

        \[\leadsto \left(\left(\log z + \log \left(e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      7. pow-to-expN/A

        \[\leadsto \left(\left(\log z + \log \left({t}^{\left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      8. log-pow-revN/A

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

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

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

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

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

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

        \[\leadsto \left(\mathsf{fma}\left(\log t, a - \frac{1}{2}, \log z\right) + \log y\right) - t \]
      15. lower-log.f6474.7

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

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

      \[\leadsto \left(a \cdot \log t + \log y\right) - t \]
    9. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
      2. lower-*.f64N/A

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
      3. lower-log.f6461.0

        \[\leadsto \left(\log t \cdot a + \log y\right) - t \]
    10. Applied rewrites61.0%

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

    if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 700

    1. Initial program 99.5%

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

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

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

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

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

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

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

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

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

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

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

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

      \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \left(z \cdot \color{blue}{y}\right) - t\right) \]
    6. Step-by-step derivation
      1. +-commutative61.0

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot y\right) - t\right) \]
    7. Applied rewrites61.0%

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

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

    1. Initial program 99.8%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \left(\log \left(y + x\right) + \left(\mathsf{neg}\left(t\right)\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
      2. lower-neg.f6478.5

        \[\leadsto \left(\log \left(y + x\right) + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    7. Applied rewrites78.5%

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

      \[\leadsto \left(\log \color{blue}{y} + \left(-t\right)\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
    9. Step-by-step derivation
      1. +-commutative62.8

        \[\leadsto \left(\log y + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
    10. Applied rewrites62.8%

      \[\leadsto \left(\log \color{blue}{y} + \left(-t\right)\right) + \left(a - 0.5\right) \cdot \log t \]
  3. Recombined 3 regimes into one program.
  4. Add Preprocessing

Alternative 8: 80.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 280:\\ \;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, -t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 280.0)
   (+ (fma (log t) (- a 0.5) (log z)) (log y))
   (fma (- a 0.5) (log t) (- t))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 280.0) {
		tmp = fma(log(t), (a - 0.5), log(z)) + log(y);
	} else {
		tmp = fma((a - 0.5), log(t), -t);
	}
	return tmp;
}
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 280.0)
		tmp = Float64(fma(log(t), Float64(a - 0.5), log(z)) + log(y));
	else
		tmp = fma(Float64(a - 0.5), log(t), Float64(-t));
	end
	return tmp
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 280.0], N[(N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision], N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + (-t)), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 280:\\
\;\;\;\;\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(a - 0.5, \log t, -t\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 280

    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. lower--.f64N/A

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f6424.3

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites24.3%

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

      \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) \]
    7. Step-by-step derivation
      1. pow-to-expN/A

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\log t, a - \frac{1}{2}, \log \left(z \cdot y\right)\right) \]
      12. lower-*.f6439.7

        \[\leadsto \mathsf{fma}\left(\log t, a - 0.5, \log \left(z \cdot y\right)\right) \]
    8. Applied rewrites39.7%

      \[\leadsto \mathsf{fma}\left(\log t, \color{blue}{a - 0.5}, \log \left(z \cdot y\right)\right) \]
    9. Step-by-step derivation
      1. sum-logN/A

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

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

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

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

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

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

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

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

        \[\leadsto \left(\log z + \log \left({t}^{\left(a - \frac{1}{2}\right)}\right)\right) + \log y \]
      10. pow-to-expN/A

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

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

        \[\leadsto \log \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right) + \log y \]
    10. Applied rewrites53.0%

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

    if 280 < 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. +-commutativeN/A

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - t\right) \]
      11. lower-+.f6476.8

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - t\right) \]
    4. Applied rewrites76.8%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, -1 \cdot t\right) \]
      2. sum-logN/A

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \mathsf{neg}\left(t\right)\right) \]
      4. lower-neg.f6499.5

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, -t\right) \]
    9. Applied rewrites99.5%

      \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \color{blue}{-t}\right) \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 9: 99.6% accurate, 1.0× speedup?

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

\\
\left(\mathsf{fma}\left(\log t, -0.5 + a, \log \left(y + x\right)\right) + \log z\right) - t
\end{array}
Derivation
  1. Initial program 99.5%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Alternative 10: 68.7% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \left(\left(\log y + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (+ (- (+ (log y) (log z)) t) (* (- a 0.5) (log t))))
double code(double x, double y, double z, double t, double a) {
	return ((log(y) + log(z)) - t) + ((a - 0.5) * log(t));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(x, y, z, t, a)
use fmin_fmax_functions
    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(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(y) + Math.log(z)) - t) + ((a - 0.5) * Math.log(t));
}
def code(x, y, z, t, a):
	return ((math.log(y) + math.log(z)) - t) + ((a - 0.5) * math.log(t))
function code(x, y, z, t, a)
	return Float64(Float64(Float64(log(y) + log(z)) - t) + Float64(Float64(a - 0.5) * log(t)))
end
function tmp = code(x, y, z, t, a)
	tmp = ((log(y) + log(z)) - t) + ((a - 0.5) * log(t));
end
code[x_, y_, z_, t_, a_] := N[(N[(N[(N[Log[y], $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 y + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t
\end{array}
Derivation
  1. Initial program 99.5%

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

    \[\leadsto \left(\left(\log \color{blue}{y} + \log z\right) - t\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
  4. Step-by-step derivation
    1. Applied rewrites65.4%

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

    Alternative 11: 68.7% accurate, 1.0× speedup?

    \[\begin{array}{l} \\ \left(\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\right) - t \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (- (+ (fma (log t) (- a 0.5) (log z)) (log y)) t))
    double code(double x, double y, double z, double t, double a) {
    	return (fma(log(t), (a - 0.5), log(z)) + log(y)) - t;
    }
    
    function code(x, y, z, t, a)
    	return Float64(Float64(fma(log(t), Float64(a - 0.5), log(z)) + log(y)) - t)
    end
    
    code[x_, y_, z_, t_, a_] := N[(N[(N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \left(\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\right) - t
    \end{array}
    
    Derivation
    1. Initial program 99.5%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Add Preprocessing
    3. Taylor expanded in 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. lower--.f64N/A

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f6425.0

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites25.0%

      \[\leadsto \color{blue}{\log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t} \]
    6. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \log \left(y \cdot \left(z \cdot {t}^{\left(a - \frac{1}{2}\right)}\right)\right) - t \]
      2. pow-to-expN/A

        \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) - t \]
      3. sum-logN/A

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

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

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

        \[\leadsto \left(\left(\log z + \log \left(e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      7. pow-to-expN/A

        \[\leadsto \left(\left(\log z + \log \left({t}^{\left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      8. log-pow-revN/A

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

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

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

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

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

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

        \[\leadsto \left(\mathsf{fma}\left(\log t, a - \frac{1}{2}, \log z\right) + \log y\right) - t \]
      15. lower-log.f6465.4

        \[\leadsto \left(\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\right) - t \]
    7. Applied rewrites65.4%

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

    Alternative 12: 61.7% accurate, 2.9× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 4.5 \cdot 10^{+67}:\\ \;\;\;\;\log t \cdot a\\ \mathbf{else}:\\ \;\;\;\;-t\\ \end{array} \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (if (<= t 4.5e+67) (* (log t) a) (- t)))
    double code(double x, double y, double z, double t, double a) {
    	double tmp;
    	if (t <= 4.5e+67) {
    		tmp = log(t) * a;
    	} else {
    		tmp = -t;
    	}
    	return tmp;
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(x, y, z, t, a)
    use fmin_fmax_functions
        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 <= 4.5d+67) 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 <= 4.5e+67) {
    		tmp = Math.log(t) * a;
    	} else {
    		tmp = -t;
    	}
    	return tmp;
    }
    
    def code(x, y, z, t, a):
    	tmp = 0
    	if t <= 4.5e+67:
    		tmp = math.log(t) * a
    	else:
    		tmp = -t
    	return tmp
    
    function code(x, y, z, t, a)
    	tmp = 0.0
    	if (t <= 4.5e+67)
    		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 <= 4.5e+67)
    		tmp = log(t) * a;
    	else
    		tmp = -t;
    	end
    	tmp_2 = tmp;
    end
    
    code[x_, y_, z_, t_, a_] := If[LessEqual[t, 4.5e+67], N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision], (-t)]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;t \leq 4.5 \cdot 10^{+67}:\\
    \;\;\;\;\log t \cdot a\\
    
    \mathbf{else}:\\
    \;\;\;\;-t\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if t < 4.4999999999999998e67

      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

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

          \[\leadsto \log t \cdot \color{blue}{a} \]
        3. lower-log.f6446.2

          \[\leadsto \log t \cdot a \]
      5. Applied rewrites46.2%

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

      if 4.4999999999999998e67 < 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

          \[\leadsto \mathsf{neg}\left(t\right) \]
        2. lower-neg.f6482.4

          \[\leadsto -t \]
      5. Applied rewrites82.4%

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

    Alternative 13: 77.8% accurate, 2.9× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left(a - 0.5, \log t, -t\right) \end{array} \]
    (FPCore (x y z t a) :precision binary64 (fma (- a 0.5) (log t) (- t)))
    double code(double x, double y, double z, double t, double a) {
    	return fma((a - 0.5), log(t), -t);
    }
    
    function code(x, y, z, t, a)
    	return fma(Float64(a - 0.5), log(t), Float64(-t))
    end
    
    code[x_, y_, z_, t_, a_] := N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + (-t)), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left(a - 0.5, \log t, -t\right)
    \end{array}
    
    Derivation
    1. Initial program 99.5%

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - t\right) \]
      11. lower-+.f6475.3

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, \log \left(z \cdot \color{blue}{\left(y + x\right)}\right) - t\right) \]
    4. Applied rewrites75.3%

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, -1 \cdot t\right) \]
      2. sum-logN/A

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

        \[\leadsto \mathsf{fma}\left(a - \frac{1}{2}, \log t, \mathsf{neg}\left(t\right)\right) \]
      4. lower-neg.f6474.7

        \[\leadsto \mathsf{fma}\left(a - 0.5, \log t, -t\right) \]
    9. Applied rewrites74.7%

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

    Alternative 14: 75.2% accurate, 2.9× speedup?

    \[\begin{array}{l} \\ \log t \cdot a - t \end{array} \]
    (FPCore (x y z t a) :precision binary64 (- (* (log t) a) t))
    double code(double x, double y, double z, double t, double a) {
    	return (log(t) * a) - t;
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(x, y, z, t, a)
    use fmin_fmax_functions
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        real(8), intent (in) :: z
        real(8), intent (in) :: t
        real(8), intent (in) :: a
        code = (log(t) * a) - t
    end function
    
    public static double code(double x, double y, double z, double t, double a) {
    	return (Math.log(t) * a) - t;
    }
    
    def code(x, y, z, t, a):
    	return (math.log(t) * a) - t
    
    function code(x, y, z, t, a)
    	return Float64(Float64(log(t) * a) - t)
    end
    
    function tmp = code(x, y, z, t, a)
    	tmp = (log(t) * a) - t;
    end
    
    code[x_, y_, z_, t_, a_] := N[(N[(N[Log[t], $MachinePrecision] * a), $MachinePrecision] - t), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \log t \cdot a - t
    \end{array}
    
    Derivation
    1. Initial program 99.5%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Add Preprocessing
    3. Taylor expanded in 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. lower--.f64N/A

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

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

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

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

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

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

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

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

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

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - \frac{1}{2}\right)}\right) - t \]
      11. lower--.f6425.0

        \[\leadsto \log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t \]
    5. Applied rewrites25.0%

      \[\leadsto \color{blue}{\log \left(\left(y \cdot z\right) \cdot {t}^{\left(a - 0.5\right)}\right) - t} \]
    6. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \log \left(y \cdot \left(z \cdot {t}^{\left(a - \frac{1}{2}\right)}\right)\right) - t \]
      2. pow-to-expN/A

        \[\leadsto \log \left(y \cdot \left(z \cdot e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) - t \]
      3. sum-logN/A

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

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

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

        \[\leadsto \left(\left(\log z + \log \left(e^{\log t \cdot \left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      7. pow-to-expN/A

        \[\leadsto \left(\left(\log z + \log \left({t}^{\left(a - \frac{1}{2}\right)}\right)\right) + \log y\right) - t \]
      8. log-pow-revN/A

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

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

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

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

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

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

        \[\leadsto \left(\mathsf{fma}\left(\log t, a - \frac{1}{2}, \log z\right) + \log y\right) - t \]
      15. lower-log.f6465.4

        \[\leadsto \left(\mathsf{fma}\left(\log t, a - 0.5, \log z\right) + \log y\right) - t \]
    7. Applied rewrites65.4%

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

      \[\leadsto a \cdot \log t - t \]
    9. Step-by-step derivation
      1. associate-+l+N/A

        \[\leadsto a \cdot \log t - t \]
      2. +-commutativeN/A

        \[\leadsto a \cdot \log t - t \]
      3. sum-logN/A

        \[\leadsto a \cdot \log t - t \]
      4. +-commutativeN/A

        \[\leadsto a \cdot \log t - t \]
      5. *-commutativeN/A

        \[\leadsto a \cdot \log t - t \]
      6. log-pow-revN/A

        \[\leadsto a \cdot \log t - t \]
      7. log-prodN/A

        \[\leadsto a \cdot \log t - t \]
      8. *-commutativeN/A

        \[\leadsto \log t \cdot a - t \]
      9. lower-*.f64N/A

        \[\leadsto \log t \cdot a - t \]
      10. lower-log.f6471.9

        \[\leadsto \log t \cdot a - t \]
    10. Applied rewrites71.9%

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

    Alternative 15: 38.0% 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;
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(x, y, z, t, a)
    use fmin_fmax_functions
        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 99.5%

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

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

        \[\leadsto \mathsf{neg}\left(t\right) \]
      2. lower-neg.f6438.7

        \[\leadsto -t \]
    5. Applied rewrites38.7%

      \[\leadsto \color{blue}{-t} \]
    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)));
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(x, y, z, t, a)
    use fmin_fmax_functions
        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 2025044 
    (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))))