Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 16.6s
Alternatives: 16
Speedup: 1.0×

Specification

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

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

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 16 alternatives:

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

Initial Program: 99.6% accurate, 1.0× speedup?

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

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

Alternative 1: 99.6% accurate, 1.0× speedup?

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

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

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

Alternative 2: 75.1% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\ t_2 := \mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-t\right)\\ \mathbf{if}\;t\_1 \leq -2 \cdot 10^{+15}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;t\_1 \leq 890:\\ \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log \left(\left(x + y\right) \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;t\_2\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))
        (t_2 (+ (fma (log t) (+ a -0.5) (log y)) (- t))))
   (if (<= t_1 -2e+15)
     t_2
     (if (<= t_1 890.0) (- (fma -0.5 (log t) (log (* (+ x y) z))) t) t_2))))
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 t_2 = fma(log(t), (a + -0.5), log(y)) + -t;
	double tmp;
	if (t_1 <= -2e+15) {
		tmp = t_2;
	} else if (t_1 <= 890.0) {
		tmp = fma(-0.5, log(t), log(((x + y) * z))) - t;
	} else {
		tmp = t_2;
	}
	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)))
	t_2 = Float64(fma(log(t), Float64(a + -0.5), log(y)) + Float64(-t))
	tmp = 0.0
	if (t_1 <= -2e+15)
		tmp = t_2;
	elseif (t_1 <= 890.0)
		tmp = Float64(fma(-0.5, log(t), log(Float64(Float64(x + y) * z))) - t);
	else
		tmp = t_2;
	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]}, Block[{t$95$2 = N[(N[(N[Log[t], $MachinePrecision] * N[(a + -0.5), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] + (-t)), $MachinePrecision]}, If[LessEqual[t$95$1, -2e+15], t$95$2, If[LessEqual[t$95$1, 890.0], N[(N[(-0.5 * N[Log[t], $MachinePrecision] + N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], t$95$2]]]]
\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\\
t_2 := \mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-t\right)\\
\mathbf{if}\;t\_1 \leq -2 \cdot 10^{+15}:\\
\;\;\;\;t\_2\\

\mathbf{elif}\;t\_1 \leq 890:\\
\;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log \left(\left(x + y\right) \cdot z\right)\right) - t\\

\mathbf{else}:\\
\;\;\;\;t\_2\\


\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))) < -2e15 or 890 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t)))

    1. Initial program 99.8%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(a + \frac{-1}{2}, \log t, \log \left(x + y\right)\right) + \color{blue}{\left(\mathsf{neg}\left(t\right)\right)} \]
      2. lower-neg.f6493.9

        \[\leadsto \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right) + \color{blue}{\left(-t\right)} \]
    7. Applied rewrites93.9%

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\log t, \color{blue}{a + \frac{-1}{2}}, \log y\right) + \left(\mathsf{neg}\left(t\right)\right) \]
      7. lower-log.f6469.3

        \[\leadsto \mathsf{fma}\left(\log t, a + -0.5, \color{blue}{\log y}\right) + \left(-t\right) \]
    10. Applied rewrites69.3%

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

    if -2e15 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 890

    1. Initial program 98.9%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(a, a, \frac{-1}{4}\right) \cdot \log t, \color{blue}{\frac{1}{a + \frac{1}{2}}}, \left(\log \left(x + y\right) + \log z\right) - t\right) \]
      15. lower-+.f6498.9

        \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(a, a, -0.25\right) \cdot \log t, \frac{1}{\color{blue}{a + 0.5}}, \left(\log \left(x + y\right) + \log z\right) - t\right) \]
    4. Applied rewrites93.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(a, a, -0.25\right) \cdot \log t, \frac{1}{a + 0.5}, \log \left(\left(x + y\right) \cdot z\right) - t\right)} \]
    5. Taylor expanded in a around 0

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\frac{-1}{2}, \log t, \log \color{blue}{\left(z \cdot \left(x + y\right)\right)}\right) - t \]
      7. lower-+.f6489.9

        \[\leadsto \mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot \color{blue}{\left(x + y\right)}\right)\right) - t \]
    7. Applied rewrites89.9%

      \[\leadsto \color{blue}{\mathsf{fma}\left(-0.5, \log t, \log \left(z \cdot \left(x + y\right)\right)\right) - t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification73.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq -2 \cdot 10^{+15}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-t\right)\\ \mathbf{elif}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq 890:\\ \;\;\;\;\mathsf{fma}\left(-0.5, \log t, \log \left(\left(x + y\right) \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-t\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 78.9% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\ \mathbf{if}\;t\_1 \leq -600:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \mathbf{elif}\;t\_1 \leq 890:\\ \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log \left(y \cdot z\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-t\right)\\ \end{array} \end{array} \]
(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 -600.0)
     (+ (- (log z) t) (* a (log t)))
     (if (<= t_1 890.0)
       (fma (log t) (+ a -0.5) (log (* y z)))
       (+ (fma (log t) (+ a -0.5) (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 <= -600.0) {
		tmp = (log(z) - t) + (a * log(t));
	} else if (t_1 <= 890.0) {
		tmp = fma(log(t), (a + -0.5), log((y * z)));
	} else {
		tmp = fma(log(t), (a + -0.5), 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 <= -600.0)
		tmp = Float64(Float64(log(z) - t) + Float64(a * log(t)));
	elseif (t_1 <= 890.0)
		tmp = fma(log(t), Float64(a + -0.5), log(Float64(y * z)));
	else
		tmp = Float64(fma(log(t), Float64(a + -0.5), log(y)) + 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, -600.0], N[(N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$1, 890.0], N[(N[Log[t], $MachinePrecision] * N[(a + -0.5), $MachinePrecision] + N[Log[N[(y * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[t], $MachinePrecision] * N[(a + -0.5), $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 -600:\\
\;\;\;\;\left(\log z - t\right) + a \cdot \log t\\

\mathbf{elif}\;t\_1 \leq 890:\\
\;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log \left(y \cdot z\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-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))) < -600

    1. Initial program 99.8%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

        \[\leadsto \color{blue}{\log t \cdot a} + \left(\log z - t\right) \]
      3. lower-log.f6496.4

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

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

    if -600 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 890

    1. Initial program 98.9%

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

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

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

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

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

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

      \[\leadsto \color{blue}{\mathsf{fma}\left({\log \left(\left(x + y\right) \cdot z\right)}^{2} - t \cdot t, \frac{1}{\log \left(\left(x + y\right) \cdot z\right) + t}, \left(a + -0.5\right) \cdot \log t\right)} \]
    5. Taylor expanded in t around 0

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

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

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

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

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

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

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

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

        \[\leadsto \mathsf{fma}\left(\log t, a + \frac{-1}{2}, \log \color{blue}{\left(z \cdot \left(x + y\right)\right)}\right) \]
      9. lower-+.f6497.1

        \[\leadsto \mathsf{fma}\left(\log t, a + -0.5, \log \left(z \cdot \color{blue}{\left(x + y\right)}\right)\right) \]
    7. Applied rewrites97.1%

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

      \[\leadsto \mathsf{fma}\left(\log t, a + \frac{-1}{2}, \log \left(y \cdot z\right)\right) \]
    9. Step-by-step derivation
      1. Applied rewrites47.1%

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

      if 890 < (+.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. lift-+.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

          \[\leadsto \mathsf{fma}\left(a + \frac{-1}{2}, \log t, \log \left(x + y\right)\right) + \color{blue}{\left(\mathsf{neg}\left(t\right)\right)} \]
        2. lower-neg.f6482.1

          \[\leadsto \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right) + \color{blue}{\left(-t\right)} \]
      7. Applied rewrites82.1%

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

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

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

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

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

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

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

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

          \[\leadsto \mathsf{fma}\left(\log t, a + -0.5, \color{blue}{\log y}\right) + \left(-t\right) \]
      10. Applied rewrites62.2%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\log t, a + -0.5, \log y\right)} + \left(-t\right) \]
    10. Recombined 3 regimes into one program.
    11. Final simplification79.1%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq -600:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \mathbf{elif}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq 890:\\ \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log \left(y \cdot z\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-t\right)\\ \end{array} \]
    12. Add Preprocessing

    Alternative 4: 83.8% accurate, 0.4× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\ t_2 := \left(\log z - t\right) + a \cdot \log t\\ \mathbf{if}\;t\_1 \leq -600:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;t\_1 \leq 890:\\ \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log \left(y \cdot z\right)\right)\\ \mathbf{else}:\\ \;\;\;\;t\_2\\ \end{array} \end{array} \]
    (FPCore (x y z t a)
     :precision binary64
     (let* ((t_1 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))
            (t_2 (+ (- (log z) t) (* a (log t)))))
       (if (<= t_1 -600.0)
         t_2
         (if (<= t_1 890.0) (fma (log t) (+ a -0.5) (log (* y z))) t_2))))
    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 t_2 = (log(z) - t) + (a * log(t));
    	double tmp;
    	if (t_1 <= -600.0) {
    		tmp = t_2;
    	} else if (t_1 <= 890.0) {
    		tmp = fma(log(t), (a + -0.5), log((y * z)));
    	} else {
    		tmp = t_2;
    	}
    	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)))
    	t_2 = Float64(Float64(log(z) - t) + Float64(a * log(t)))
    	tmp = 0.0
    	if (t_1 <= -600.0)
    		tmp = t_2;
    	elseif (t_1 <= 890.0)
    		tmp = fma(log(t), Float64(a + -0.5), log(Float64(y * z)));
    	else
    		tmp = t_2;
    	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]}, Block[{t$95$2 = N[(N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, -600.0], t$95$2, If[LessEqual[t$95$1, 890.0], N[(N[Log[t], $MachinePrecision] * N[(a + -0.5), $MachinePrecision] + N[Log[N[(y * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], t$95$2]]]]
    
    \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\\
    t_2 := \left(\log z - t\right) + a \cdot \log t\\
    \mathbf{if}\;t\_1 \leq -600:\\
    \;\;\;\;t\_2\\
    
    \mathbf{elif}\;t\_1 \leq 890:\\
    \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log \left(y \cdot z\right)\right)\\
    
    \mathbf{else}:\\
    \;\;\;\;t\_2\\
    
    
    \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))) < -600 or 890 < (+.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 99.7%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

          \[\leadsto \color{blue}{\log t \cdot a} + \left(\log z - t\right) \]
        3. lower-log.f6491.8

          \[\leadsto \color{blue}{\log t} \cdot a + \left(\log z - t\right) \]
      7. Applied rewrites91.8%

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

      if -600 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 890

      1. Initial program 98.9%

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

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

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

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

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

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

        \[\leadsto \color{blue}{\mathsf{fma}\left({\log \left(\left(x + y\right) \cdot z\right)}^{2} - t \cdot t, \frac{1}{\log \left(\left(x + y\right) \cdot z\right) + t}, \left(a + -0.5\right) \cdot \log t\right)} \]
      5. Taylor expanded in t around 0

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

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

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

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

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

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

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

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

          \[\leadsto \mathsf{fma}\left(\log t, a + \frac{-1}{2}, \log \color{blue}{\left(z \cdot \left(x + y\right)\right)}\right) \]
        9. lower-+.f6497.1

          \[\leadsto \mathsf{fma}\left(\log t, a + -0.5, \log \left(z \cdot \color{blue}{\left(x + y\right)}\right)\right) \]
      7. Applied rewrites97.1%

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

        \[\leadsto \mathsf{fma}\left(\log t, a + \frac{-1}{2}, \log \left(y \cdot z\right)\right) \]
      9. Step-by-step derivation
        1. Applied rewrites47.1%

          \[\leadsto \mathsf{fma}\left(\log t, a + -0.5, \log \left(y \cdot z\right)\right) \]
      10. Recombined 2 regimes into one program.
      11. Final simplification84.3%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq -600:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \mathbf{elif}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq 890:\\ \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log \left(y \cdot z\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \end{array} \]
      12. Add Preprocessing

      Alternative 5: 92.4% accurate, 0.4× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_1 := \left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\\ t_2 := \left(\log z - t\right) + a \cdot \log t\\ \mathbf{if}\;t\_1 \leq -600:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;t\_1 \leq 890:\\ \;\;\;\;\mathsf{fma}\left(\log t, -0.5, \log \left(\left(x + y\right) \cdot z\right)\right)\\ \mathbf{else}:\\ \;\;\;\;t\_2\\ \end{array} \end{array} \]
      (FPCore (x y z t a)
       :precision binary64
       (let* ((t_1 (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))
              (t_2 (+ (- (log z) t) (* a (log t)))))
         (if (<= t_1 -600.0)
           t_2
           (if (<= t_1 890.0) (fma (log t) -0.5 (log (* (+ x y) z))) t_2))))
      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 t_2 = (log(z) - t) + (a * log(t));
      	double tmp;
      	if (t_1 <= -600.0) {
      		tmp = t_2;
      	} else if (t_1 <= 890.0) {
      		tmp = fma(log(t), -0.5, log(((x + y) * z)));
      	} else {
      		tmp = t_2;
      	}
      	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)))
      	t_2 = Float64(Float64(log(z) - t) + Float64(a * log(t)))
      	tmp = 0.0
      	if (t_1 <= -600.0)
      		tmp = t_2;
      	elseif (t_1 <= 890.0)
      		tmp = fma(log(t), -0.5, log(Float64(Float64(x + y) * z)));
      	else
      		tmp = t_2;
      	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]}, Block[{t$95$2 = N[(N[(N[Log[z], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$1, -600.0], t$95$2, If[LessEqual[t$95$1, 890.0], N[(N[Log[t], $MachinePrecision] * -0.5 + N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], t$95$2]]]]
      
      \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\\
      t_2 := \left(\log z - t\right) + a \cdot \log t\\
      \mathbf{if}\;t\_1 \leq -600:\\
      \;\;\;\;t\_2\\
      
      \mathbf{elif}\;t\_1 \leq 890:\\
      \;\;\;\;\mathsf{fma}\left(\log t, -0.5, \log \left(\left(x + y\right) \cdot z\right)\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;t\_2\\
      
      
      \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))) < -600 or 890 < (+.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 99.7%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \color{blue}{\log t \cdot a} + \left(\log z - t\right) \]
          3. lower-log.f6491.8

            \[\leadsto \color{blue}{\log t} \cdot a + \left(\log z - t\right) \]
        7. Applied rewrites91.8%

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

        if -600 < (+.f64 (-.f64 (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) t) (*.f64 (-.f64 a #s(literal 1/2 binary64)) (log.f64 t))) < 890

        1. Initial program 98.9%

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

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

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

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

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

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

          \[\leadsto \color{blue}{\mathsf{fma}\left({\log \left(\left(x + y\right) \cdot z\right)}^{2} - t \cdot t, \frac{1}{\log \left(\left(x + y\right) \cdot z\right) + t}, \left(a + -0.5\right) \cdot \log t\right)} \]
        5. Taylor expanded in t around 0

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

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

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

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

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

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

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

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

            \[\leadsto \mathsf{fma}\left(\log t, a + \frac{-1}{2}, \log \color{blue}{\left(z \cdot \left(x + y\right)\right)}\right) \]
          9. lower-+.f6497.1

            \[\leadsto \mathsf{fma}\left(\log t, a + -0.5, \log \left(z \cdot \color{blue}{\left(x + y\right)}\right)\right) \]
        7. Applied rewrites97.1%

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

          \[\leadsto \mathsf{fma}\left(\log t, \frac{-1}{2}, \log \left(z \cdot \left(x + y\right)\right)\right) \]
        9. Step-by-step derivation
          1. Applied rewrites94.8%

            \[\leadsto \mathsf{fma}\left(\log t, -0.5, \log \left(z \cdot \left(x + y\right)\right)\right) \]
        10. Recombined 2 regimes into one program.
        11. Final simplification92.3%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq -600:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \mathbf{elif}\;\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \leq 890:\\ \;\;\;\;\mathsf{fma}\left(\log t, -0.5, \log \left(\left(x + y\right) \cdot z\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \end{array} \]
        12. Add Preprocessing

        Alternative 6: 93.9% accurate, 0.5× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -750:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \mathbf{elif}\;t\_1 \leq 650:\\ \;\;\;\;\mathsf{fma}\left(a + -0.5, \log t, \log \left(\left(x + y\right) \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(a - 0.5\right) \cdot \log t + \mathsf{fma}\left(\frac{\log z}{t}, t, -t\right)\\ \end{array} \end{array} \]
        (FPCore (x y z t a)
         :precision binary64
         (let* ((t_1 (+ (log (+ x y)) (log z))))
           (if (<= t_1 -750.0)
             (+ (- (log z) t) (* a (log t)))
             (if (<= t_1 650.0)
               (- (fma (+ a -0.5) (log t) (log (* (+ x y) z))) t)
               (+ (* (- a 0.5) (log t)) (fma (/ (log z) t) t (- 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(z) - t) + (a * log(t));
        	} else if (t_1 <= 650.0) {
        		tmp = fma((a + -0.5), log(t), log(((x + y) * z))) - t;
        	} else {
        		tmp = ((a - 0.5) * log(t)) + fma((log(z) / t), t, -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(log(z) - t) + Float64(a * log(t)));
        	elseif (t_1 <= 650.0)
        		tmp = Float64(fma(Float64(a + -0.5), log(t), log(Float64(Float64(x + y) * z))) - t);
        	else
        		tmp = Float64(Float64(Float64(a - 0.5) * log(t)) + fma(Float64(log(z) / t), t, Float64(-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[Log[z], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$1, 650.0], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Log[z], $MachinePrecision] / t), $MachinePrecision] * t + (-t)), $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 z - t\right) + a \cdot \log t\\
        
        \mathbf{elif}\;t\_1 \leq 650:\\
        \;\;\;\;\mathsf{fma}\left(a + -0.5, \log t, \log \left(\left(x + y\right) \cdot z\right)\right) - t\\
        
        \mathbf{else}:\\
        \;\;\;\;\left(a - 0.5\right) \cdot \log t + \mathsf{fma}\left(\frac{\log z}{t}, t, -t\right)\\
        
        
        \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. Step-by-step derivation
            1. lift-+.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

              \[\leadsto \color{blue}{\log t \cdot a} + \left(\log z - t\right) \]
            3. lower-log.f6479.1

              \[\leadsto \color{blue}{\log t} \cdot a + \left(\log z - t\right) \]
          7. Applied rewrites79.1%

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

          if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 650

          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. lift-+.f64N/A

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

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

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

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

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

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

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

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

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

              \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}, \log t, \log \left(x + y\right) + \log z\right) - t \]
            11. metadata-eval99.6

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

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

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

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

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

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

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

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

          if 650 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z))

          1. Initial program 99.8%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \color{blue}{\mathsf{fma}\left(t, \frac{\log z}{t} + \frac{\log \left(y + x\right)}{t}, -t\right)} + \left(a - 0.5\right) \cdot \log t \]
          6. Step-by-step derivation
            1. Applied rewrites99.7%

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

              \[\leadsto \mathsf{fma}\left(\frac{\log z}{t}, t, -1 \cdot t\right) + \left(a - \frac{1}{2}\right) \cdot \log t \]
            3. Step-by-step derivation
              1. Applied rewrites83.7%

                \[\leadsto \mathsf{fma}\left(\frac{\log z}{t}, t, -t\right) + \left(a - 0.5\right) \cdot \log t \]
            4. Recombined 3 regimes into one program.
            5. Final simplification94.7%

              \[\leadsto \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq -750:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \mathbf{elif}\;\log \left(x + y\right) + \log z \leq 650:\\ \;\;\;\;\mathsf{fma}\left(a + -0.5, \log t, \log \left(\left(x + y\right) \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(a - 0.5\right) \cdot \log t + \mathsf{fma}\left(\frac{\log z}{t}, t, -t\right)\\ \end{array} \]
            6. Add Preprocessing

            Alternative 7: 89.2% accurate, 0.5× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} t_1 := \log \left(x + y\right) + \log z\\ \mathbf{if}\;t\_1 \leq -750:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \mathbf{elif}\;t\_1 \leq 650:\\ \;\;\;\;\mathsf{fma}\left(a + -0.5, \log t, \log \left(\left(x + y\right) \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-t\right)\\ \end{array} \end{array} \]
            (FPCore (x y z t a)
             :precision binary64
             (let* ((t_1 (+ (log (+ x y)) (log z))))
               (if (<= t_1 -750.0)
                 (+ (- (log z) t) (* a (log t)))
                 (if (<= t_1 650.0)
                   (- (fma (+ a -0.5) (log t) (log (* (+ x y) z))) t)
                   (+ (fma (log t) (+ a -0.5) (log y)) (- t))))))
            double code(double x, double y, double z, double t, double a) {
            	double t_1 = log((x + y)) + log(z);
            	double tmp;
            	if (t_1 <= -750.0) {
            		tmp = (log(z) - t) + (a * log(t));
            	} else if (t_1 <= 650.0) {
            		tmp = fma((a + -0.5), log(t), log(((x + y) * z))) - t;
            	} else {
            		tmp = fma(log(t), (a + -0.5), log(y)) + -t;
            	}
            	return tmp;
            }
            
            function code(x, y, z, t, a)
            	t_1 = Float64(log(Float64(x + y)) + log(z))
            	tmp = 0.0
            	if (t_1 <= -750.0)
            		tmp = Float64(Float64(log(z) - t) + Float64(a * log(t)));
            	elseif (t_1 <= 650.0)
            		tmp = Float64(fma(Float64(a + -0.5), log(t), log(Float64(Float64(x + y) * z))) - t);
            	else
            		tmp = Float64(fma(log(t), Float64(a + -0.5), log(y)) + Float64(-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[Log[z], $MachinePrecision] - t), $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$1, 650.0], N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision] + N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(N[Log[t], $MachinePrecision] * N[(a + -0.5), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] + (-t)), $MachinePrecision]]]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            t_1 := \log \left(x + y\right) + \log z\\
            \mathbf{if}\;t\_1 \leq -750:\\
            \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\
            
            \mathbf{elif}\;t\_1 \leq 650:\\
            \;\;\;\;\mathsf{fma}\left(a + -0.5, \log t, \log \left(\left(x + y\right) \cdot z\right)\right) - t\\
            
            \mathbf{else}:\\
            \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-t\right)\\
            
            
            \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. Step-by-step derivation
                1. lift-+.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                  \[\leadsto \color{blue}{\log t \cdot a} + \left(\log z - t\right) \]
                3. lower-log.f6479.1

                  \[\leadsto \color{blue}{\log t} \cdot a + \left(\log z - t\right) \]
              7. Applied rewrites79.1%

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

              if -750 < (+.f64 (log.f64 (+.f64 x y)) (log.f64 z)) < 650

              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. lift-+.f64N/A

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

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

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

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

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

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

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

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

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

                  \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}, \log t, \log \left(x + y\right) + \log z\right) - t \]
                11. metadata-eval99.6

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

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

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

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

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

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

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

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

              if 650 < (+.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. lift-+.f64N/A

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                  \[\leadsto \mathsf{fma}\left(a + \frac{-1}{2}, \log t, \log \left(x + y\right)\right) + \color{blue}{\left(\mathsf{neg}\left(t\right)\right)} \]
                2. lower-neg.f6483.6

                  \[\leadsto \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right) + \color{blue}{\left(-t\right)} \]
              7. Applied rewrites83.6%

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

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

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

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

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

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

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

                  \[\leadsto \mathsf{fma}\left(\log t, \color{blue}{a + \frac{-1}{2}}, \log y\right) + \left(\mathsf{neg}\left(t\right)\right) \]
                7. lower-log.f6464.9

                  \[\leadsto \mathsf{fma}\left(\log t, a + -0.5, \color{blue}{\log y}\right) + \left(-t\right) \]
              10. Applied rewrites64.9%

                \[\leadsto \color{blue}{\mathsf{fma}\left(\log t, a + -0.5, \log y\right)} + \left(-t\right) \]
            3. Recombined 3 regimes into one program.
            4. Final simplification89.9%

              \[\leadsto \begin{array}{l} \mathbf{if}\;\log \left(x + y\right) + \log z \leq -750:\\ \;\;\;\;\left(\log z - t\right) + a \cdot \log t\\ \mathbf{elif}\;\log \left(x + y\right) + \log z \leq 650:\\ \;\;\;\;\mathsf{fma}\left(a + -0.5, \log t, \log \left(\left(x + y\right) \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-t\right)\\ \end{array} \]
            5. Add Preprocessing

            Alternative 8: 68.5% accurate, 1.0× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 0.0012:\\ \;\;\;\;\log y + \mathsf{fma}\left(\log t, a + -0.5, \log z\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-t\right)\\ \end{array} \end{array} \]
            (FPCore (x y z t a)
             :precision binary64
             (if (<= t 0.0012)
               (+ (log y) (fma (log t) (+ a -0.5) (log z)))
               (+ (fma (log t) (+ a -0.5) (log y)) (- t))))
            double code(double x, double y, double z, double t, double a) {
            	double tmp;
            	if (t <= 0.0012) {
            		tmp = log(y) + fma(log(t), (a + -0.5), log(z));
            	} else {
            		tmp = fma(log(t), (a + -0.5), log(y)) + -t;
            	}
            	return tmp;
            }
            
            function code(x, y, z, t, a)
            	tmp = 0.0
            	if (t <= 0.0012)
            		tmp = Float64(log(y) + fma(log(t), Float64(a + -0.5), log(z)));
            	else
            		tmp = Float64(fma(log(t), Float64(a + -0.5), log(y)) + Float64(-t));
            	end
            	return tmp
            end
            
            code[x_, y_, z_, t_, a_] := If[LessEqual[t, 0.0012], N[(N[Log[y], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * N[(a + -0.5), $MachinePrecision] + N[Log[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[t], $MachinePrecision] * N[(a + -0.5), $MachinePrecision] + N[Log[y], $MachinePrecision]), $MachinePrecision] + (-t)), $MachinePrecision]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;t \leq 0.0012:\\
            \;\;\;\;\log y + \mathsf{fma}\left(\log t, a + -0.5, \log z\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;\mathsf{fma}\left(\log t, a + -0.5, \log y\right) + \left(-t\right)\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if t < 0.00119999999999999989

              1. Initial program 99.3%

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

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

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

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

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

                  \[\leadsto \color{blue}{\mathsf{fma}\left(\left(\log \left(x + y\right) + \log z\right) \cdot \left(\log \left(x + y\right) + \log z\right) - t \cdot t, \frac{1}{\left(\log \left(x + y\right) + \log z\right) + t}, \left(a - \frac{1}{2}\right) \cdot \log t\right)} \]
              4. Applied rewrites71.9%

                \[\leadsto \color{blue}{\mathsf{fma}\left({\log \left(\left(x + y\right) \cdot z\right)}^{2} - t \cdot t, \frac{1}{\log \left(\left(x + y\right) \cdot z\right) + t}, \left(a + -0.5\right) \cdot \log t\right)} \]
              5. Taylor expanded in t around 0

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

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

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

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

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

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

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

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

                  \[\leadsto \mathsf{fma}\left(\log t, a + \frac{-1}{2}, \log \color{blue}{\left(z \cdot \left(x + y\right)\right)}\right) \]
                9. lower-+.f6471.9

                  \[\leadsto \mathsf{fma}\left(\log t, a + -0.5, \log \left(z \cdot \color{blue}{\left(x + y\right)}\right)\right) \]
              7. Applied rewrites71.9%

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

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

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

                if 0.00119999999999999989 < t

                1. Initial program 99.9%

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \mathsf{fma}\left(a + \frac{-1}{2}, \log t, \log \left(x + y\right)\right) + \color{blue}{\left(\mathsf{neg}\left(t\right)\right)} \]
                  2. lower-neg.f6498.7

                    \[\leadsto \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right) + \color{blue}{\left(-t\right)} \]
                7. Applied rewrites98.7%

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

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

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

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

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

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

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

                    \[\leadsto \mathsf{fma}\left(\log t, \color{blue}{a + \frac{-1}{2}}, \log y\right) + \left(\mathsf{neg}\left(t\right)\right) \]
                  7. lower-log.f6473.8

                    \[\leadsto \mathsf{fma}\left(\log t, a + -0.5, \color{blue}{\log y}\right) + \left(-t\right) \]
                10. Applied rewrites73.8%

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

              Alternative 9: 99.6% accurate, 1.0× speedup?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

              Alternative 10: 69.2% accurate, 1.0× speedup?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

              Alternative 11: 76.9% accurate, 1.5× speedup?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                  \[\leadsto \color{blue}{\log t \cdot a} + \left(\log z - t\right) \]
                3. lower-log.f6478.7

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

                \[\leadsto \color{blue}{\log t \cdot a} + \left(\log z - t\right) \]
              8. Final simplification78.7%

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

              Alternative 12: 64.6% accurate, 2.5× speedup?

              \[\begin{array}{l} \\ \begin{array}{l} t_1 := a \cdot \log t\\ \mathbf{if}\;a - 0.5 \leq -1 \cdot 10^{+55}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;a - 0.5 \leq 10^{+70}:\\ \;\;\;\;\log \left(x + y\right) + \left(-t\right)\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \end{array} \]
              (FPCore (x y z t a)
               :precision binary64
               (let* ((t_1 (* a (log t))))
                 (if (<= (- a 0.5) -1e+55)
                   t_1
                   (if (<= (- a 0.5) 1e+70) (+ (log (+ x y)) (- t)) t_1))))
              double code(double x, double y, double z, double t, double a) {
              	double t_1 = a * log(t);
              	double tmp;
              	if ((a - 0.5) <= -1e+55) {
              		tmp = t_1;
              	} else if ((a - 0.5) <= 1e+70) {
              		tmp = log((x + y)) + -t;
              	} else {
              		tmp = t_1;
              	}
              	return tmp;
              }
              
              real(8) function code(x, y, z, t, a)
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  real(8), intent (in) :: z
                  real(8), intent (in) :: t
                  real(8), intent (in) :: a
                  real(8) :: t_1
                  real(8) :: tmp
                  t_1 = a * log(t)
                  if ((a - 0.5d0) <= (-1d+55)) then
                      tmp = t_1
                  else if ((a - 0.5d0) <= 1d+70) then
                      tmp = log((x + y)) + -t
                  else
                      tmp = t_1
                  end if
                  code = tmp
              end function
              
              public static double code(double x, double y, double z, double t, double a) {
              	double t_1 = a * Math.log(t);
              	double tmp;
              	if ((a - 0.5) <= -1e+55) {
              		tmp = t_1;
              	} else if ((a - 0.5) <= 1e+70) {
              		tmp = Math.log((x + y)) + -t;
              	} else {
              		tmp = t_1;
              	}
              	return tmp;
              }
              
              def code(x, y, z, t, a):
              	t_1 = a * math.log(t)
              	tmp = 0
              	if (a - 0.5) <= -1e+55:
              		tmp = t_1
              	elif (a - 0.5) <= 1e+70:
              		tmp = math.log((x + y)) + -t
              	else:
              		tmp = t_1
              	return tmp
              
              function code(x, y, z, t, a)
              	t_1 = Float64(a * log(t))
              	tmp = 0.0
              	if (Float64(a - 0.5) <= -1e+55)
              		tmp = t_1;
              	elseif (Float64(a - 0.5) <= 1e+70)
              		tmp = Float64(log(Float64(x + y)) + Float64(-t));
              	else
              		tmp = t_1;
              	end
              	return tmp
              end
              
              function tmp_2 = code(x, y, z, t, a)
              	t_1 = a * log(t);
              	tmp = 0.0;
              	if ((a - 0.5) <= -1e+55)
              		tmp = t_1;
              	elseif ((a - 0.5) <= 1e+70)
              		tmp = log((x + y)) + -t;
              	else
              		tmp = t_1;
              	end
              	tmp_2 = tmp;
              end
              
              code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(a - 0.5), $MachinePrecision], -1e+55], t$95$1, If[LessEqual[N[(a - 0.5), $MachinePrecision], 1e+70], N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + (-t)), $MachinePrecision], t$95$1]]]
              
              \begin{array}{l}
              
              \\
              \begin{array}{l}
              t_1 := a \cdot \log t\\
              \mathbf{if}\;a - 0.5 \leq -1 \cdot 10^{+55}:\\
              \;\;\;\;t\_1\\
              
              \mathbf{elif}\;a - 0.5 \leq 10^{+70}:\\
              \;\;\;\;\log \left(x + y\right) + \left(-t\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;t\_1\\
              
              
              \end{array}
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if (-.f64 a #s(literal 1/2 binary64)) < -1.00000000000000001e55 or 1.00000000000000007e70 < (-.f64 a #s(literal 1/2 binary64))

                1. Initial program 99.7%

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

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

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

                    \[\leadsto \color{blue}{\log t \cdot a} \]
                  3. lower-log.f6481.4

                    \[\leadsto \color{blue}{\log t} \cdot a \]
                5. Applied rewrites81.4%

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

                if -1.00000000000000001e55 < (-.f64 a #s(literal 1/2 binary64)) < 1.00000000000000007e70

                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

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

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \log \left(y + x\right) + \left(\mathsf{fma}\left(\color{blue}{\log t}, \frac{-1}{2}, \log z\right) - t\right) \]
                  12. lower-log.f6490.7

                    \[\leadsto \log \left(y + x\right) + \left(\mathsf{fma}\left(\log t, -0.5, \color{blue}{\log z}\right) - t\right) \]
                5. Applied rewrites90.7%

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

                  \[\leadsto \log \left(y + x\right) + -1 \cdot \color{blue}{t} \]
                7. Step-by-step derivation
                  1. Applied rewrites57.5%

                    \[\leadsto \log \left(y + x\right) + \left(-t\right) \]
                8. Recombined 2 regimes into one program.
                9. Final simplification67.2%

                  \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -1 \cdot 10^{+55}:\\ \;\;\;\;a \cdot \log t\\ \mathbf{elif}\;a - 0.5 \leq 10^{+70}:\\ \;\;\;\;\log \left(x + y\right) + \left(-t\right)\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t\\ \end{array} \]
                10. Add Preprocessing

                Alternative 13: 61.9% accurate, 2.6× speedup?

                \[\begin{array}{l} \\ \begin{array}{l} t_1 := a \cdot \log t\\ \mathbf{if}\;a - 0.5 \leq -5 \cdot 10^{+25}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;a - 0.5 \leq 10^{+70}:\\ \;\;\;\;-t\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \end{array} \]
                (FPCore (x y z t a)
                 :precision binary64
                 (let* ((t_1 (* a (log t))))
                   (if (<= (- a 0.5) -5e+25) t_1 (if (<= (- a 0.5) 1e+70) (- t) t_1))))
                double code(double x, double y, double z, double t, double a) {
                	double t_1 = a * log(t);
                	double tmp;
                	if ((a - 0.5) <= -5e+25) {
                		tmp = t_1;
                	} else if ((a - 0.5) <= 1e+70) {
                		tmp = -t;
                	} else {
                		tmp = t_1;
                	}
                	return tmp;
                }
                
                real(8) function code(x, y, z, t, a)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    real(8), intent (in) :: z
                    real(8), intent (in) :: t
                    real(8), intent (in) :: a
                    real(8) :: t_1
                    real(8) :: tmp
                    t_1 = a * log(t)
                    if ((a - 0.5d0) <= (-5d+25)) then
                        tmp = t_1
                    else if ((a - 0.5d0) <= 1d+70) then
                        tmp = -t
                    else
                        tmp = t_1
                    end if
                    code = tmp
                end function
                
                public static double code(double x, double y, double z, double t, double a) {
                	double t_1 = a * Math.log(t);
                	double tmp;
                	if ((a - 0.5) <= -5e+25) {
                		tmp = t_1;
                	} else if ((a - 0.5) <= 1e+70) {
                		tmp = -t;
                	} else {
                		tmp = t_1;
                	}
                	return tmp;
                }
                
                def code(x, y, z, t, a):
                	t_1 = a * math.log(t)
                	tmp = 0
                	if (a - 0.5) <= -5e+25:
                		tmp = t_1
                	elif (a - 0.5) <= 1e+70:
                		tmp = -t
                	else:
                		tmp = t_1
                	return tmp
                
                function code(x, y, z, t, a)
                	t_1 = Float64(a * log(t))
                	tmp = 0.0
                	if (Float64(a - 0.5) <= -5e+25)
                		tmp = t_1;
                	elseif (Float64(a - 0.5) <= 1e+70)
                		tmp = Float64(-t);
                	else
                		tmp = t_1;
                	end
                	return tmp
                end
                
                function tmp_2 = code(x, y, z, t, a)
                	t_1 = a * log(t);
                	tmp = 0.0;
                	if ((a - 0.5) <= -5e+25)
                		tmp = t_1;
                	elseif ((a - 0.5) <= 1e+70)
                		tmp = -t;
                	else
                		tmp = t_1;
                	end
                	tmp_2 = tmp;
                end
                
                code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(a - 0.5), $MachinePrecision], -5e+25], t$95$1, If[LessEqual[N[(a - 0.5), $MachinePrecision], 1e+70], (-t), t$95$1]]]
                
                \begin{array}{l}
                
                \\
                \begin{array}{l}
                t_1 := a \cdot \log t\\
                \mathbf{if}\;a - 0.5 \leq -5 \cdot 10^{+25}:\\
                \;\;\;\;t\_1\\
                
                \mathbf{elif}\;a - 0.5 \leq 10^{+70}:\\
                \;\;\;\;-t\\
                
                \mathbf{else}:\\
                \;\;\;\;t\_1\\
                
                
                \end{array}
                \end{array}
                
                Derivation
                1. Split input into 2 regimes
                2. if (-.f64 a #s(literal 1/2 binary64)) < -5.00000000000000024e25 or 1.00000000000000007e70 < (-.f64 a #s(literal 1/2 binary64))

                  1. Initial program 99.7%

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

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

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

                      \[\leadsto \color{blue}{\log t \cdot a} \]
                    3. lower-log.f6479.3

                      \[\leadsto \color{blue}{\log t} \cdot a \]
                  5. Applied rewrites79.3%

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

                  if -5.00000000000000024e25 < (-.f64 a #s(literal 1/2 binary64)) < 1.00000000000000007e70

                  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

                      \[\leadsto \color{blue}{\mathsf{neg}\left(t\right)} \]
                    2. lower-neg.f6453.0

                      \[\leadsto \color{blue}{-t} \]
                  5. Applied rewrites53.0%

                    \[\leadsto \color{blue}{-t} \]
                3. Recombined 2 regimes into one program.
                4. Final simplification64.5%

                  \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -5 \cdot 10^{+25}:\\ \;\;\;\;a \cdot \log t\\ \mathbf{elif}\;a - 0.5 \leq 10^{+70}:\\ \;\;\;\;-t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t\\ \end{array} \]
                5. Add Preprocessing

                Alternative 14: 77.2% accurate, 2.8× speedup?

                \[\begin{array}{l} \\ \left(a - 0.5\right) \cdot \log t + \left(-t\right) \end{array} \]
                (FPCore (x y z t a) :precision binary64 (+ (* (- a 0.5) (log t)) (- t)))
                double code(double x, double y, double z, double t, double a) {
                	return ((a - 0.5) * log(t)) + -t;
                }
                
                real(8) function code(x, y, z, t, a)
                    real(8), intent (in) :: x
                    real(8), intent (in) :: y
                    real(8), intent (in) :: z
                    real(8), intent (in) :: t
                    real(8), intent (in) :: a
                    code = ((a - 0.5d0) * log(t)) + -t
                end function
                
                public static double code(double x, double y, double z, double t, double a) {
                	return ((a - 0.5) * Math.log(t)) + -t;
                }
                
                def code(x, y, z, t, a):
                	return ((a - 0.5) * math.log(t)) + -t
                
                function code(x, y, z, t, a)
                	return Float64(Float64(Float64(a - 0.5) * log(t)) + Float64(-t))
                end
                
                function tmp = code(x, y, z, t, a)
                	tmp = ((a - 0.5) * log(t)) + -t;
                end
                
                code[x_, y_, z_, t_, a_] := N[(N[(N[(a - 0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] + (-t)), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \left(a - 0.5\right) \cdot \log t + \left(-t\right)
                \end{array}
                
                Derivation
                1. Initial program 99.6%

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

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

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

                    \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
                5. Applied rewrites78.2%

                  \[\leadsto \color{blue}{\left(-t\right)} + \left(a - 0.5\right) \cdot \log t \]
                6. Final simplification78.2%

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

                Alternative 15: 74.5% accurate, 2.9× speedup?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

                    \[\leadsto \mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right)\right) + \color{blue}{\left(-t\right)} \]
                7. Applied rewrites78.8%

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

                  \[\leadsto \color{blue}{a \cdot \log t} + \left(\mathsf{neg}\left(t\right)\right) \]
                9. Step-by-step derivation
                  1. *-commutativeN/A

                    \[\leadsto \color{blue}{\log t \cdot a} + \left(\mathsf{neg}\left(t\right)\right) \]
                  2. lower-*.f64N/A

                    \[\leadsto \color{blue}{\log t \cdot a} + \left(\mathsf{neg}\left(t\right)\right) \]
                  3. lower-log.f6476.1

                    \[\leadsto \color{blue}{\log t} \cdot a + \left(-t\right) \]
                10. Applied rewrites76.1%

                  \[\leadsto \color{blue}{\log t \cdot a} + \left(-t\right) \]
                11. Final simplification76.1%

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

                Alternative 16: 37.6% accurate, 107.0× speedup?

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

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

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

                    \[\leadsto \color{blue}{\mathsf{neg}\left(t\right)} \]
                  2. lower-neg.f6439.2

                    \[\leadsto \color{blue}{-t} \]
                5. Applied rewrites39.2%

                  \[\leadsto \color{blue}{-t} \]
                6. Add Preprocessing

                Developer Target 1: 99.6% accurate, 1.0× speedup?

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

                Reproduce

                ?
                herbie shell --seed 2024219 
                (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))))