Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2

Percentage Accurate: 99.6% → 99.6%
Time: 30.0s
Alternatives: 14
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 14 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, 0.8× speedup?

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

\\
\mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right) + \left(\log z - t\right)\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. Step-by-step derivation
    1. +-commutative99.6%

      \[\leadsto \color{blue}{\left(a - 0.5\right) \cdot \log t + \left(\left(\log \left(x + y\right) + \log z\right) - t\right)} \]
    2. fma-def99.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \left(\log \left(x + y\right) + \log z\right) - t\right)} \]
    3. sub-neg99.7%

      \[\leadsto \mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \left(\log \left(x + y\right) + \log z\right) - t\right) \]
    4. metadata-eval99.7%

      \[\leadsto \mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \left(\log \left(x + y\right) + \log z\right) - t\right) \]
    5. associate--l+99.6%

      \[\leadsto \mathsf{fma}\left(a + -0.5, \log t, \color{blue}{\log \left(x + y\right) + \left(\log z - t\right)}\right) \]
  3. Simplified99.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(a + -0.5, \log t, \log \left(x + y\right) + \left(\log z - t\right)\right)} \]
  4. Final simplification99.6%

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

Alternative 2: 80.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -2000000 \lor \neg \left(a - 0.5 \leq 0.4\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + \left(\log z + -0.5 \cdot \log t\right)\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (or (<= (- a 0.5) -2000000.0) (not (<= (- a 0.5) 0.4)))
   (- (* a (log t)) t)
   (- (+ (log y) (+ (log z) (* -0.5 (log t)))) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (((a - 0.5) <= -2000000.0) || !((a - 0.5) <= 0.4)) {
		tmp = (a * log(t)) - t;
	} else {
		tmp = (log(y) + (log(z) + (-0.5 * log(t)))) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (((a - 0.5d0) <= (-2000000.0d0)) .or. (.not. ((a - 0.5d0) <= 0.4d0))) then
        tmp = (a * log(t)) - t
    else
        tmp = (log(y) + (log(z) + ((-0.5d0) * log(t)))) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (((a - 0.5) <= -2000000.0) || !((a - 0.5) <= 0.4)) {
		tmp = (a * Math.log(t)) - t;
	} else {
		tmp = (Math.log(y) + (Math.log(z) + (-0.5 * Math.log(t)))) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if ((a - 0.5) <= -2000000.0) or not ((a - 0.5) <= 0.4):
		tmp = (a * math.log(t)) - t
	else:
		tmp = (math.log(y) + (math.log(z) + (-0.5 * math.log(t)))) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if ((Float64(a - 0.5) <= -2000000.0) || !(Float64(a - 0.5) <= 0.4))
		tmp = Float64(Float64(a * log(t)) - t);
	else
		tmp = Float64(Float64(log(y) + Float64(log(z) + Float64(-0.5 * log(t)))) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (((a - 0.5) <= -2000000.0) || ~(((a - 0.5) <= 0.4)))
		tmp = (a * log(t)) - t;
	else
		tmp = (log(y) + (log(z) + (-0.5 * log(t)))) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[Or[LessEqual[N[(a - 0.5), $MachinePrecision], -2000000.0], N[Not[LessEqual[N[(a - 0.5), $MachinePrecision], 0.4]], $MachinePrecision]], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] + N[(N[Log[z], $MachinePrecision] + N[(-0.5 * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a - 0.5 \leq -2000000 \lor \neg \left(a - 0.5 \leq 0.4\right):\\
\;\;\;\;a \cdot \log t - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 a 1/2) < -2e6 or 0.40000000000000002 < (-.f64 a 1/2)

    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. Step-by-step derivation
      1. associate--l+99.8%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.8%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.8%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in x around 0 70.6%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    5. Taylor expanded in a around inf 98.3%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    6. Step-by-step derivation
      1. *-commutative98.3%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    7. Simplified98.3%

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

    if -2e6 < (-.f64 a 1/2) < 0.40000000000000002

    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. Step-by-step derivation
      1. associate--l+99.5%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.5%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.5%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.5%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.5%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.5%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.5%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.5%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in x around 0 61.9%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    5. Taylor expanded in a around 0 61.6%

      \[\leadsto \left(\log y + \color{blue}{\left(\log z + -0.5 \cdot \log t\right)}\right) - t \]
    6. Step-by-step derivation
      1. *-commutative61.6%

        \[\leadsto \left(\log y + \left(\log z + \color{blue}{\log t \cdot -0.5}\right)\right) - t \]
    7. Simplified61.6%

      \[\leadsto \left(\log y + \color{blue}{\left(\log z + \log t \cdot -0.5\right)}\right) - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -2000000 \lor \neg \left(a - 0.5 \leq 0.4\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + \left(\log z + -0.5 \cdot \log t\right)\right) - t\\ \end{array} \]

Alternative 3: 76.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -2000000 \lor \neg \left(a - 0.5 \leq 0.4\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log z + \log \left(y \cdot {t}^{-0.5}\right)\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (or (<= (- a 0.5) -2000000.0) (not (<= (- a 0.5) 0.4)))
   (- (* a (log t)) t)
   (- (+ (log z) (log (* y (pow t -0.5)))) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (((a - 0.5) <= -2000000.0) || !((a - 0.5) <= 0.4)) {
		tmp = (a * log(t)) - t;
	} else {
		tmp = (log(z) + log((y * pow(t, -0.5)))) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (((a - 0.5d0) <= (-2000000.0d0)) .or. (.not. ((a - 0.5d0) <= 0.4d0))) then
        tmp = (a * log(t)) - t
    else
        tmp = (log(z) + log((y * (t ** (-0.5d0))))) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (((a - 0.5) <= -2000000.0) || !((a - 0.5) <= 0.4)) {
		tmp = (a * Math.log(t)) - t;
	} else {
		tmp = (Math.log(z) + Math.log((y * Math.pow(t, -0.5)))) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if ((a - 0.5) <= -2000000.0) or not ((a - 0.5) <= 0.4):
		tmp = (a * math.log(t)) - t
	else:
		tmp = (math.log(z) + math.log((y * math.pow(t, -0.5)))) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if ((Float64(a - 0.5) <= -2000000.0) || !(Float64(a - 0.5) <= 0.4))
		tmp = Float64(Float64(a * log(t)) - t);
	else
		tmp = Float64(Float64(log(z) + log(Float64(y * (t ^ -0.5)))) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (((a - 0.5) <= -2000000.0) || ~(((a - 0.5) <= 0.4)))
		tmp = (a * log(t)) - t;
	else
		tmp = (log(z) + log((y * (t ^ -0.5)))) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[Or[LessEqual[N[(a - 0.5), $MachinePrecision], -2000000.0], N[Not[LessEqual[N[(a - 0.5), $MachinePrecision], 0.4]], $MachinePrecision]], N[(N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(N[Log[z], $MachinePrecision] + N[Log[N[(y * N[Power[t, -0.5], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;a - 0.5 \leq -2000000 \lor \neg \left(a - 0.5 \leq 0.4\right):\\
\;\;\;\;a \cdot \log t - t\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 a 1/2) < -2e6 or 0.40000000000000002 < (-.f64 a 1/2)

    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. Step-by-step derivation
      1. associate--l+99.8%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.8%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.8%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in x around 0 70.6%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    5. Taylor expanded in a around inf 98.3%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    6. Step-by-step derivation
      1. *-commutative98.3%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    7. Simplified98.3%

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

    if -2e6 < (-.f64 a 1/2) < 0.40000000000000002

    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. Step-by-step derivation
      1. associate--l+99.5%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.5%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.5%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.5%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.5%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.5%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.5%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.5%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around 0 98.5%

      \[\leadsto \color{blue}{\left(\log z + \left(\log \left(x + y\right) + -0.5 \cdot \log t\right)\right) - t} \]
    5. Taylor expanded in z around inf 98.5%

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(-1 \cdot \log \left(\frac{1}{z}\right) + -0.5 \cdot \log t\right)\right)} - t \]
    6. Step-by-step derivation
      1. associate-+r+98.6%

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + -1 \cdot \log \left(\frac{1}{z}\right)\right) + -0.5 \cdot \log t\right)} - t \]
      2. +-commutative98.6%

        \[\leadsto \left(\color{blue}{\left(-1 \cdot \log \left(\frac{1}{z}\right) + \log \left(x + y\right)\right)} + -0.5 \cdot \log t\right) - t \]
      3. mul-1-neg98.6%

        \[\leadsto \left(\left(\color{blue}{\left(-\log \left(\frac{1}{z}\right)\right)} + \log \left(x + y\right)\right) + -0.5 \cdot \log t\right) - t \]
      4. log-rec98.6%

        \[\leadsto \left(\left(\left(-\color{blue}{\left(-\log z\right)}\right) + \log \left(x + y\right)\right) + -0.5 \cdot \log t\right) - t \]
      5. remove-double-neg98.6%

        \[\leadsto \left(\left(\color{blue}{\log z} + \log \left(x + y\right)\right) + -0.5 \cdot \log t\right) - t \]
      6. log-prod76.6%

        \[\leadsto \left(\color{blue}{\log \left(z \cdot \left(x + y\right)\right)} + -0.5 \cdot \log t\right) - t \]
      7. +-commutative76.6%

        \[\leadsto \left(\log \left(z \cdot \color{blue}{\left(y + x\right)}\right) + -0.5 \cdot \log t\right) - t \]
      8. log-pow76.6%

        \[\leadsto \left(\log \left(z \cdot \left(y + x\right)\right) + \color{blue}{\log \left({t}^{-0.5}\right)}\right) - t \]
      9. log-prod69.8%

        \[\leadsto \color{blue}{\log \left(\left(z \cdot \left(y + x\right)\right) \cdot {t}^{-0.5}\right)} - t \]
      10. *-commutative69.8%

        \[\leadsto \log \color{blue}{\left({t}^{-0.5} \cdot \left(z \cdot \left(y + x\right)\right)\right)} - t \]
    7. Simplified69.8%

      \[\leadsto \color{blue}{\log \left({t}^{-0.5} \cdot \left(z \cdot \left(y + x\right)\right)\right)} - t \]
    8. Taylor expanded in y around inf 43.1%

      \[\leadsto \log \left({t}^{-0.5} \cdot \color{blue}{\left(y \cdot z\right)}\right) - t \]
    9. Step-by-step derivation
      1. associate-*r*42.5%

        \[\leadsto \log \color{blue}{\left(\left({t}^{-0.5} \cdot y\right) \cdot z\right)} - t \]
      2. log-prod51.8%

        \[\leadsto \color{blue}{\left(\log \left({t}^{-0.5} \cdot y\right) + \log z\right)} - t \]
    10. Applied egg-rr51.8%

      \[\leadsto \color{blue}{\left(\log \left({t}^{-0.5} \cdot y\right) + \log z\right)} - t \]
  3. Recombined 2 regimes into one program.
  4. Final simplification76.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a - 0.5 \leq -2000000 \lor \neg \left(a - 0.5 \leq 0.4\right):\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log z + \log \left(y \cdot {t}^{-0.5}\right)\right) - t\\ \end{array} \]

Alternative 4: 99.6% accurate, 1.0× speedup?

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

\\
\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \log t \cdot \left(a - 0.5\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. Final simplification99.6%

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

Alternative 5: 69.2% accurate, 1.0× speedup?

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

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

    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
  2. Step-by-step derivation
    1. associate--l+99.6%

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    2. associate-+l+99.6%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
    3. +-commutative99.6%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
    4. associate-+r-99.6%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
    5. fma-def99.6%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
    6. sub-neg99.6%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
    7. metadata-eval99.6%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
  3. Simplified99.6%

    \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
  4. Taylor expanded in x around 0 66.5%

    \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
  5. Final simplification66.5%

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

Alternative 6: 85.7% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq 3.1 \cdot 10^{+97}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \left(\left(a + -0.5\right) \cdot \log t - t\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + y\right) + \mathsf{fma}\left(\log t, a, -t\right)\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= z 3.1e+97)
   (+ (log (* (+ x y) z)) (- (* (+ a -0.5) (log t)) t))
   (+ (log (+ x y)) (fma (log t) a (- t)))))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (z <= 3.1e+97) {
		tmp = log(((x + y) * z)) + (((a + -0.5) * log(t)) - t);
	} else {
		tmp = log((x + y)) + fma(log(t), a, -t);
	}
	return tmp;
}
function code(x, y, z, t, a)
	tmp = 0.0
	if (z <= 3.1e+97)
		tmp = Float64(log(Float64(Float64(x + y) * z)) + Float64(Float64(Float64(a + -0.5) * log(t)) - t));
	else
		tmp = Float64(log(Float64(x + y)) + fma(log(t), a, Float64(-t)));
	end
	return tmp
end
code[x_, y_, z_, t_, a_] := If[LessEqual[z, 3.1e+97], N[(N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision] + N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision], N[(N[Log[N[(x + y), $MachinePrecision]], $MachinePrecision] + N[(N[Log[t], $MachinePrecision] * a + (-t)), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq 3.1 \cdot 10^{+97}:\\
\;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \left(\left(a + -0.5\right) \cdot \log t - t\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < 3.09999999999999981e97

    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. Step-by-step derivation
      1. associate-+l-99.5%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right) - \left(t - \left(a - 0.5\right) \cdot \log t\right)} \]
      2. +-commutative99.5%

        \[\leadsto \color{blue}{\left(\log z + \log \left(x + y\right)\right)} - \left(t - \left(a - 0.5\right) \cdot \log t\right) \]
      3. sum-log91.1%

        \[\leadsto \color{blue}{\log \left(z \cdot \left(x + y\right)\right)} - \left(t - \left(a - 0.5\right) \cdot \log t\right) \]
      4. sub-neg91.1%

        \[\leadsto \log \left(z \cdot \left(x + y\right)\right) - \left(t - \color{blue}{\left(a + \left(-0.5\right)\right)} \cdot \log t\right) \]
      5. metadata-eval91.1%

        \[\leadsto \log \left(z \cdot \left(x + y\right)\right) - \left(t - \left(a + \color{blue}{-0.5}\right) \cdot \log t\right) \]
    3. Applied egg-rr91.1%

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

    if 3.09999999999999981e97 < 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. Step-by-step derivation
      1. associate--l+99.8%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.8%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.8%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 82.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative82.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified82.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    7. Taylor expanded in t around 0 82.9%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(-1 \cdot t + a \cdot \log t\right)} \]
    8. Step-by-step derivation
      1. neg-mul-182.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\left(-t\right)} + a \cdot \log t\right) \]
      2. +-commutative82.9%

        \[\leadsto \log \color{blue}{\left(y + x\right)} + \left(\left(-t\right) + a \cdot \log t\right) \]
      3. +-commutative82.9%

        \[\leadsto \log \left(y + x\right) + \color{blue}{\left(a \cdot \log t + \left(-t\right)\right)} \]
      4. *-commutative82.9%

        \[\leadsto \log \left(y + x\right) + \left(\color{blue}{\log t \cdot a} + \left(-t\right)\right) \]
      5. fma-udef82.9%

        \[\leadsto \log \left(y + x\right) + \color{blue}{\mathsf{fma}\left(\log t, a, -t\right)} \]
    9. Simplified82.9%

      \[\leadsto \color{blue}{\log \left(y + x\right) + \mathsf{fma}\left(\log t, a, -t\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification88.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq 3.1 \cdot 10^{+97}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \left(\left(a + -0.5\right) \cdot \log t - t\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(x + y\right) + \mathsf{fma}\left(\log t, a, -t\right)\\ \end{array} \]

Alternative 7: 79.2% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq 2.2 \cdot 10^{+97}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \left(\left(a + -0.5\right) \cdot \log t - t\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= z 2.2e+97)
   (+ (log (* (+ x y) z)) (- (* (+ a -0.5) (log t)) t))
   (- (+ (log y) (* a (log t))) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (z <= 2.2e+97) {
		tmp = log(((x + y) * z)) + (((a + -0.5) * log(t)) - t);
	} else {
		tmp = (log(y) + (a * log(t))) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (z <= 2.2d+97) then
        tmp = log(((x + y) * z)) + (((a + (-0.5d0)) * log(t)) - t)
    else
        tmp = (log(y) + (a * log(t))) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (z <= 2.2e+97) {
		tmp = Math.log(((x + y) * z)) + (((a + -0.5) * Math.log(t)) - t);
	} else {
		tmp = (Math.log(y) + (a * Math.log(t))) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if z <= 2.2e+97:
		tmp = math.log(((x + y) * z)) + (((a + -0.5) * math.log(t)) - t)
	else:
		tmp = (math.log(y) + (a * math.log(t))) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (z <= 2.2e+97)
		tmp = Float64(log(Float64(Float64(x + y) * z)) + Float64(Float64(Float64(a + -0.5) * log(t)) - t));
	else
		tmp = Float64(Float64(log(y) + Float64(a * log(t))) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (z <= 2.2e+97)
		tmp = log(((x + y) * z)) + (((a + -0.5) * log(t)) - t);
	else
		tmp = (log(y) + (a * log(t))) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[z, 2.2e+97], N[(N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision] + N[(N[(N[(a + -0.5), $MachinePrecision] * N[Log[t], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq 2.2 \cdot 10^{+97}:\\
\;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \left(\left(a + -0.5\right) \cdot \log t - t\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < 2.2000000000000001e97

    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. Step-by-step derivation
      1. associate-+l-99.5%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \log z\right) - \left(t - \left(a - 0.5\right) \cdot \log t\right)} \]
      2. +-commutative99.5%

        \[\leadsto \color{blue}{\left(\log z + \log \left(x + y\right)\right)} - \left(t - \left(a - 0.5\right) \cdot \log t\right) \]
      3. sum-log91.1%

        \[\leadsto \color{blue}{\log \left(z \cdot \left(x + y\right)\right)} - \left(t - \left(a - 0.5\right) \cdot \log t\right) \]
      4. sub-neg91.1%

        \[\leadsto \log \left(z \cdot \left(x + y\right)\right) - \left(t - \color{blue}{\left(a + \left(-0.5\right)\right)} \cdot \log t\right) \]
      5. metadata-eval91.1%

        \[\leadsto \log \left(z \cdot \left(x + y\right)\right) - \left(t - \left(a + \color{blue}{-0.5}\right) \cdot \log t\right) \]
    3. Applied egg-rr91.1%

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

    if 2.2000000000000001e97 < 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. Step-by-step derivation
      1. associate--l+99.8%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.8%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.8%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 82.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative82.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified82.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    7. Taylor expanded in x around 0 62.0%

      \[\leadsto \color{blue}{\left(\log y + a \cdot \log t\right) - t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq 2.2 \cdot 10^{+97}:\\ \;\;\;\;\log \left(\left(x + y\right) \cdot z\right) + \left(\left(a + -0.5\right) \cdot \log t - t\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \end{array} \]

Alternative 8: 67.0% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := a \cdot \log t\\ \mathbf{if}\;a \leq -0.00088:\\ \;\;\;\;t_1 - t\\ \mathbf{elif}\;a \leq 6 \cdot 10^{-45}:\\ \;\;\;\;\left(-0.5 \cdot \log t + \log \left(y \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + t_1\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (* a (log t))))
   (if (<= a -0.00088)
     (- t_1 t)
     (if (<= a 6e-45)
       (- (+ (* -0.5 (log t)) (log (* y z))) t)
       (- (+ (log y) t_1) t)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = a * log(t);
	double tmp;
	if (a <= -0.00088) {
		tmp = t_1 - t;
	} else if (a <= 6e-45) {
		tmp = ((-0.5 * log(t)) + log((y * z))) - t;
	} else {
		tmp = (log(y) + t_1) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: t_1
    real(8) :: tmp
    t_1 = a * log(t)
    if (a <= (-0.00088d0)) then
        tmp = t_1 - t
    else if (a <= 6d-45) then
        tmp = (((-0.5d0) * log(t)) + log((y * z))) - t
    else
        tmp = (log(y) + t_1) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = a * Math.log(t);
	double tmp;
	if (a <= -0.00088) {
		tmp = t_1 - t;
	} else if (a <= 6e-45) {
		tmp = ((-0.5 * Math.log(t)) + Math.log((y * z))) - t;
	} else {
		tmp = (Math.log(y) + t_1) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = a * math.log(t)
	tmp = 0
	if a <= -0.00088:
		tmp = t_1 - t
	elif a <= 6e-45:
		tmp = ((-0.5 * math.log(t)) + math.log((y * z))) - t
	else:
		tmp = (math.log(y) + t_1) - t
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(a * log(t))
	tmp = 0.0
	if (a <= -0.00088)
		tmp = Float64(t_1 - t);
	elseif (a <= 6e-45)
		tmp = Float64(Float64(Float64(-0.5 * log(t)) + log(Float64(y * z))) - t);
	else
		tmp = Float64(Float64(log(y) + t_1) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = a * log(t);
	tmp = 0.0;
	if (a <= -0.00088)
		tmp = t_1 - t;
	elseif (a <= 6e-45)
		tmp = ((-0.5 * log(t)) + log((y * z))) - t;
	else
		tmp = (log(y) + t_1) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[a, -0.00088], N[(t$95$1 - t), $MachinePrecision], If[LessEqual[a, 6e-45], N[(N[(N[(-0.5 * N[Log[t], $MachinePrecision]), $MachinePrecision] + N[Log[N[(y * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] + t$95$1), $MachinePrecision] - t), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := a \cdot \log t\\
\mathbf{if}\;a \leq -0.00088:\\
\;\;\;\;t_1 - t\\

\mathbf{elif}\;a \leq 6 \cdot 10^{-45}:\\
\;\;\;\;\left(-0.5 \cdot \log t + \log \left(y \cdot z\right)\right) - t\\

\mathbf{else}:\\
\;\;\;\;\left(\log y + t_1\right) - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if a < -8.80000000000000031e-4

    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. Step-by-step derivation
      1. associate--l+99.8%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.8%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.8%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in x around 0 62.2%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    5. Taylor expanded in a around inf 99.1%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    6. Step-by-step derivation
      1. *-commutative99.1%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    7. Simplified99.1%

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

    if -8.80000000000000031e-4 < a < 6.00000000000000022e-45

    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. Step-by-step derivation
      1. associate--l+99.5%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.5%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.5%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.5%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.5%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.5%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.5%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.5%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in x around 0 60.9%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    5. Taylor expanded in a around 0 60.9%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + -0.5 \cdot \log t\right)\right)} - t \]
    6. Step-by-step derivation
      1. associate-+r+60.8%

        \[\leadsto \color{blue}{\left(\left(\log y + \log z\right) + -0.5 \cdot \log t\right)} - t \]
      2. log-prod50.4%

        \[\leadsto \left(\color{blue}{\log \left(y \cdot z\right)} + -0.5 \cdot \log t\right) - t \]
      3. *-commutative50.4%

        \[\leadsto \left(\log \color{blue}{\left(z \cdot y\right)} + -0.5 \cdot \log t\right) - t \]
      4. *-commutative50.4%

        \[\leadsto \left(\log \left(z \cdot y\right) + \color{blue}{\log t \cdot -0.5}\right) - t \]
    7. Simplified50.4%

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

    if 6.00000000000000022e-45 < a

    1. Initial program 99.7%

      \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
    2. Step-by-step derivation
      1. associate--l+99.7%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.7%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.7%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.7%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 92.6%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative92.6%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified92.6%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    7. Taylor expanded in x around 0 73.3%

      \[\leadsto \color{blue}{\left(\log y + a \cdot \log t\right) - t} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification70.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -0.00088:\\ \;\;\;\;a \cdot \log t - t\\ \mathbf{elif}\;a \leq 6 \cdot 10^{-45}:\\ \;\;\;\;\left(-0.5 \cdot \log t + \log \left(y \cdot z\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \end{array} \]

Alternative 9: 74.4% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq 0.0013:\\ \;\;\;\;\log t \cdot \left(a - 0.5\right) + \log \left(\left(x + y\right) \cdot z\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (if (<= t 0.0013)
   (+ (* (log t) (- a 0.5)) (log (* (+ x y) z)))
   (- (+ (log y) (* a (log t))) t)))
double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.0013) {
		tmp = (log(t) * (a - 0.5)) + log(((x + y) * z));
	} else {
		tmp = (log(y) + (a * log(t))) - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: tmp
    if (t <= 0.0013d0) then
        tmp = (log(t) * (a - 0.5d0)) + log(((x + y) * z))
    else
        tmp = (log(y) + (a * log(t))) - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double tmp;
	if (t <= 0.0013) {
		tmp = (Math.log(t) * (a - 0.5)) + Math.log(((x + y) * z));
	} else {
		tmp = (Math.log(y) + (a * Math.log(t))) - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	tmp = 0
	if t <= 0.0013:
		tmp = (math.log(t) * (a - 0.5)) + math.log(((x + y) * z))
	else:
		tmp = (math.log(y) + (a * math.log(t))) - t
	return tmp
function code(x, y, z, t, a)
	tmp = 0.0
	if (t <= 0.0013)
		tmp = Float64(Float64(log(t) * Float64(a - 0.5)) + log(Float64(Float64(x + y) * z)));
	else
		tmp = Float64(Float64(log(y) + Float64(a * log(t))) - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	tmp = 0.0;
	if (t <= 0.0013)
		tmp = (log(t) * (a - 0.5)) + log(((x + y) * z));
	else
		tmp = (log(y) + (a * log(t))) - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := If[LessEqual[t, 0.0013], N[(N[(N[Log[t], $MachinePrecision] * N[(a - 0.5), $MachinePrecision]), $MachinePrecision] + N[Log[N[(N[(x + y), $MachinePrecision] * z), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[(N[Log[y], $MachinePrecision] + N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq 0.0013:\\
\;\;\;\;\log t \cdot \left(a - 0.5\right) + \log \left(\left(x + y\right) \cdot z\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < 0.0012999999999999999

    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. Step-by-step derivation
      1. add-cbrt-cube70.4%

        \[\leadsto \color{blue}{\sqrt[3]{\left(\left(\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\right) \cdot \left(\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\right)\right) \cdot \left(\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\right)}} \]
      2. pow370.5%

        \[\leadsto \sqrt[3]{\color{blue}{{\left(\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\right)}^{3}}} \]
      3. +-commutative70.5%

        \[\leadsto \sqrt[3]{{\color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\left(\log \left(x + y\right) + \log z\right) - t\right)\right)}}^{3}} \]
      4. sub-neg70.5%

        \[\leadsto \sqrt[3]{{\left(\color{blue}{\left(a + \left(-0.5\right)\right)} \cdot \log t + \left(\left(\log \left(x + y\right) + \log z\right) - t\right)\right)}^{3}} \]
      5. metadata-eval70.5%

        \[\leadsto \sqrt[3]{{\left(\left(a + \color{blue}{-0.5}\right) \cdot \log t + \left(\left(\log \left(x + y\right) + \log z\right) - t\right)\right)}^{3}} \]
      6. fma-def70.5%

        \[\leadsto \sqrt[3]{{\color{blue}{\left(\mathsf{fma}\left(a + -0.5, \log t, \left(\log \left(x + y\right) + \log z\right) - t\right)\right)}}^{3}} \]
      7. +-commutative70.5%

        \[\leadsto \sqrt[3]{{\left(\mathsf{fma}\left(a + -0.5, \log t, \color{blue}{\left(\log z + \log \left(x + y\right)\right)} - t\right)\right)}^{3}} \]
      8. sum-log55.3%

        \[\leadsto \sqrt[3]{{\left(\mathsf{fma}\left(a + -0.5, \log t, \color{blue}{\log \left(z \cdot \left(x + y\right)\right)} - t\right)\right)}^{3}} \]
    3. Applied egg-rr55.3%

      \[\leadsto \color{blue}{\sqrt[3]{{\left(\mathsf{fma}\left(a + -0.5, \log t, \log \left(z \cdot \left(x + y\right)\right) - t\right)\right)}^{3}}} \]
    4. Taylor expanded in t around 0 75.7%

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

    if 0.0012999999999999999 < 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. Step-by-step derivation
      1. associate--l+99.9%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.9%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.9%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.9%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.9%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 99.4%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative99.4%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified99.4%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    7. Taylor expanded in x around 0 70.1%

      \[\leadsto \color{blue}{\left(\log y + a \cdot \log t\right) - t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification72.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq 0.0013:\\ \;\;\;\;\log t \cdot \left(a - 0.5\right) + \log \left(\left(x + y\right) \cdot z\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \end{array} \]

Alternative 10: 65.0% accurate, 1.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := a \cdot \log t\\ \mathbf{if}\;a \leq -3.5 \cdot 10^{-20}:\\ \;\;\;\;\left(\log y + t_1\right) - t\\ \mathbf{elif}\;a \leq 0.00055:\\ \;\;\;\;\log \left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;t_1 - t\\ \end{array} \end{array} \]
(FPCore (x y z t a)
 :precision binary64
 (let* ((t_1 (* a (log t))))
   (if (<= a -3.5e-20)
     (- (+ (log y) t_1) t)
     (if (<= a 0.00055) (- (log (* y (* z (pow t -0.5)))) t) (- t_1 t)))))
double code(double x, double y, double z, double t, double a) {
	double t_1 = a * log(t);
	double tmp;
	if (a <= -3.5e-20) {
		tmp = (log(y) + t_1) - t;
	} else if (a <= 0.00055) {
		tmp = log((y * (z * pow(t, -0.5)))) - t;
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
real(8) function code(x, y, z, t, a)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8), intent (in) :: a
    real(8) :: t_1
    real(8) :: tmp
    t_1 = a * log(t)
    if (a <= (-3.5d-20)) then
        tmp = (log(y) + t_1) - t
    else if (a <= 0.00055d0) then
        tmp = log((y * (z * (t ** (-0.5d0))))) - t
    else
        tmp = t_1 - t
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t, double a) {
	double t_1 = a * Math.log(t);
	double tmp;
	if (a <= -3.5e-20) {
		tmp = (Math.log(y) + t_1) - t;
	} else if (a <= 0.00055) {
		tmp = Math.log((y * (z * Math.pow(t, -0.5)))) - t;
	} else {
		tmp = t_1 - t;
	}
	return tmp;
}
def code(x, y, z, t, a):
	t_1 = a * math.log(t)
	tmp = 0
	if a <= -3.5e-20:
		tmp = (math.log(y) + t_1) - t
	elif a <= 0.00055:
		tmp = math.log((y * (z * math.pow(t, -0.5)))) - t
	else:
		tmp = t_1 - t
	return tmp
function code(x, y, z, t, a)
	t_1 = Float64(a * log(t))
	tmp = 0.0
	if (a <= -3.5e-20)
		tmp = Float64(Float64(log(y) + t_1) - t);
	elseif (a <= 0.00055)
		tmp = Float64(log(Float64(y * Float64(z * (t ^ -0.5)))) - t);
	else
		tmp = Float64(t_1 - t);
	end
	return tmp
end
function tmp_2 = code(x, y, z, t, a)
	t_1 = a * log(t);
	tmp = 0.0;
	if (a <= -3.5e-20)
		tmp = (log(y) + t_1) - t;
	elseif (a <= 0.00055)
		tmp = log((y * (z * (t ^ -0.5)))) - t;
	else
		tmp = t_1 - t;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_, a_] := Block[{t$95$1 = N[(a * N[Log[t], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[a, -3.5e-20], N[(N[(N[Log[y], $MachinePrecision] + t$95$1), $MachinePrecision] - t), $MachinePrecision], If[LessEqual[a, 0.00055], N[(N[Log[N[(y * N[(z * N[Power[t, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - t), $MachinePrecision], N[(t$95$1 - t), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := a \cdot \log t\\
\mathbf{if}\;a \leq -3.5 \cdot 10^{-20}:\\
\;\;\;\;\left(\log y + t_1\right) - t\\

\mathbf{elif}\;a \leq 0.00055:\\
\;\;\;\;\log \left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right) - t\\

\mathbf{else}:\\
\;\;\;\;t_1 - t\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if a < -3.50000000000000003e-20

    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. Step-by-step derivation
      1. associate--l+99.8%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.8%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.8%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.8%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.8%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around inf 97.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
    5. Step-by-step derivation
      1. *-commutative97.9%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    6. Simplified97.9%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
    7. Taylor expanded in x around 0 61.6%

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

    if -3.50000000000000003e-20 < a < 5.50000000000000033e-4

    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. Step-by-step derivation
      1. associate--l+99.5%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.5%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.5%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.5%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.5%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.5%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.5%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.5%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in a around 0 98.6%

      \[\leadsto \color{blue}{\left(\log z + \left(\log \left(x + y\right) + -0.5 \cdot \log t\right)\right) - t} \]
    5. Taylor expanded in z around inf 98.7%

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(-1 \cdot \log \left(\frac{1}{z}\right) + -0.5 \cdot \log t\right)\right)} - t \]
    6. Step-by-step derivation
      1. associate-+r+98.7%

        \[\leadsto \color{blue}{\left(\left(\log \left(x + y\right) + -1 \cdot \log \left(\frac{1}{z}\right)\right) + -0.5 \cdot \log t\right)} - t \]
      2. +-commutative98.7%

        \[\leadsto \left(\color{blue}{\left(-1 \cdot \log \left(\frac{1}{z}\right) + \log \left(x + y\right)\right)} + -0.5 \cdot \log t\right) - t \]
      3. mul-1-neg98.7%

        \[\leadsto \left(\left(\color{blue}{\left(-\log \left(\frac{1}{z}\right)\right)} + \log \left(x + y\right)\right) + -0.5 \cdot \log t\right) - t \]
      4. log-rec98.7%

        \[\leadsto \left(\left(\left(-\color{blue}{\left(-\log z\right)}\right) + \log \left(x + y\right)\right) + -0.5 \cdot \log t\right) - t \]
      5. remove-double-neg98.7%

        \[\leadsto \left(\left(\color{blue}{\log z} + \log \left(x + y\right)\right) + -0.5 \cdot \log t\right) - t \]
      6. log-prod77.6%

        \[\leadsto \left(\color{blue}{\log \left(z \cdot \left(x + y\right)\right)} + -0.5 \cdot \log t\right) - t \]
      7. +-commutative77.6%

        \[\leadsto \left(\log \left(z \cdot \color{blue}{\left(y + x\right)}\right) + -0.5 \cdot \log t\right) - t \]
      8. log-pow77.6%

        \[\leadsto \left(\log \left(z \cdot \left(y + x\right)\right) + \color{blue}{\log \left({t}^{-0.5}\right)}\right) - t \]
      9. log-prod71.4%

        \[\leadsto \color{blue}{\log \left(\left(z \cdot \left(y + x\right)\right) \cdot {t}^{-0.5}\right)} - t \]
      10. *-commutative71.4%

        \[\leadsto \log \color{blue}{\left({t}^{-0.5} \cdot \left(z \cdot \left(y + x\right)\right)\right)} - t \]
    7. Simplified71.4%

      \[\leadsto \color{blue}{\log \left({t}^{-0.5} \cdot \left(z \cdot \left(y + x\right)\right)\right)} - t \]
    8. Taylor expanded in y around inf 44.5%

      \[\leadsto \log \left({t}^{-0.5} \cdot \color{blue}{\left(y \cdot z\right)}\right) - t \]
    9. Taylor expanded in y around 0 57.5%

      \[\leadsto \color{blue}{\left(\log y + \log \left(\sqrt{\frac{1}{t}} \cdot z\right)\right)} - t \]
    10. Step-by-step derivation
      1. log-prod61.0%

        \[\leadsto \left(\log y + \color{blue}{\left(\log \left(\sqrt{\frac{1}{t}}\right) + \log z\right)}\right) - t \]
      2. unpow1/261.0%

        \[\leadsto \left(\log y + \left(\log \color{blue}{\left({\left(\frac{1}{t}\right)}^{0.5}\right)} + \log z\right)\right) - t \]
      3. log-pow61.0%

        \[\leadsto \left(\log y + \left(\color{blue}{0.5 \cdot \log \left(\frac{1}{t}\right)} + \log z\right)\right) - t \]
      4. *-commutative61.0%

        \[\leadsto \left(\log y + \left(\color{blue}{\log \left(\frac{1}{t}\right) \cdot 0.5} + \log z\right)\right) - t \]
      5. log-rec61.0%

        \[\leadsto \left(\log y + \left(\color{blue}{\left(-\log t\right)} \cdot 0.5 + \log z\right)\right) - t \]
      6. distribute-lft-neg-out61.0%

        \[\leadsto \left(\log y + \left(\color{blue}{\left(-\log t \cdot 0.5\right)} + \log z\right)\right) - t \]
      7. distribute-rgt-neg-in61.0%

        \[\leadsto \left(\log y + \left(\color{blue}{\log t \cdot \left(-0.5\right)} + \log z\right)\right) - t \]
      8. metadata-eval61.0%

        \[\leadsto \left(\log y + \left(\log t \cdot \color{blue}{-0.5} + \log z\right)\right) - t \]
      9. *-commutative61.0%

        \[\leadsto \left(\log y + \left(\color{blue}{-0.5 \cdot \log t} + \log z\right)\right) - t \]
      10. log-pow61.0%

        \[\leadsto \left(\log y + \left(\color{blue}{\log \left({t}^{-0.5}\right)} + \log z\right)\right) - t \]
      11. log-prod57.5%

        \[\leadsto \left(\log y + \color{blue}{\log \left({t}^{-0.5} \cdot z\right)}\right) - t \]
      12. log-prod45.3%

        \[\leadsto \color{blue}{\log \left(y \cdot \left({t}^{-0.5} \cdot z\right)\right)} - t \]
      13. *-commutative45.3%

        \[\leadsto \log \left(y \cdot \color{blue}{\left(z \cdot {t}^{-0.5}\right)}\right) - t \]
    11. Simplified45.3%

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

    if 5.50000000000000033e-4 < a

    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. Step-by-step derivation
      1. associate--l+99.7%

        \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
      2. associate-+l+99.7%

        \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
      3. +-commutative99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
      4. associate-+r-99.7%

        \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
      5. fma-def99.7%

        \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
      6. sub-neg99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
      7. metadata-eval99.7%

        \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
    3. Simplified99.7%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
    4. Taylor expanded in x around 0 80.2%

      \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
    5. Taylor expanded in a around inf 97.4%

      \[\leadsto \color{blue}{a \cdot \log t} - t \]
    6. Step-by-step derivation
      1. *-commutative97.4%

        \[\leadsto \color{blue}{\log t \cdot a} - t \]
    7. Simplified97.4%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  3. Recombined 3 regimes into one program.
  4. Final simplification63.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;a \leq -3.5 \cdot 10^{-20}:\\ \;\;\;\;\left(\log y + a \cdot \log t\right) - t\\ \mathbf{elif}\;a \leq 0.00055:\\ \;\;\;\;\log \left(y \cdot \left(z \cdot {t}^{-0.5}\right)\right) - t\\ \mathbf{else}:\\ \;\;\;\;a \cdot \log t - t\\ \end{array} \]

Alternative 11: 58.0% accurate, 1.5× speedup?

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

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

    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
  2. Step-by-step derivation
    1. associate--l+99.6%

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    2. associate-+l+99.6%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
    3. +-commutative99.6%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
    4. associate-+r-99.6%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
    5. fma-def99.6%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
    6. sub-neg99.6%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
    7. metadata-eval99.6%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
  3. Simplified99.6%

    \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
  4. Taylor expanded in a around inf 77.3%

    \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
  5. Step-by-step derivation
    1. *-commutative77.3%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
  6. Simplified77.3%

    \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
  7. Taylor expanded in x around 0 55.1%

    \[\leadsto \color{blue}{\left(\log y + a \cdot \log t\right) - t} \]
  8. Final simplification55.1%

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

Alternative 12: 41.4% accurate, 3.0× speedup?

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

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

    \[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t \]
  2. Step-by-step derivation
    1. associate--l+99.6%

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    2. associate-+l+99.6%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
    3. +-commutative99.6%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
    4. associate-+r-99.6%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
    5. fma-def99.6%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
    6. sub-neg99.6%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
    7. metadata-eval99.6%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
  3. Simplified99.6%

    \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
  4. Taylor expanded in a around inf 77.3%

    \[\leadsto \log \left(x + y\right) + \left(\color{blue}{a \cdot \log t} - t\right) \]
  5. Step-by-step derivation
    1. *-commutative77.3%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
  6. Simplified77.3%

    \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\log t \cdot a} - t\right) \]
  7. Taylor expanded in a around 0 39.0%

    \[\leadsto \color{blue}{\log \left(x + y\right) - t} \]
  8. Step-by-step derivation
    1. +-commutative39.0%

      \[\leadsto \log \color{blue}{\left(y + x\right)} - t \]
  9. Simplified39.0%

    \[\leadsto \color{blue}{\log \left(y + x\right) - t} \]
  10. Final simplification39.0%

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

Alternative 13: 74.6% accurate, 3.0× speedup?

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

\\
a \cdot \log t - 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. Step-by-step derivation
    1. associate--l+99.6%

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    2. associate-+l+99.6%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
    3. +-commutative99.6%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
    4. associate-+r-99.6%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
    5. fma-def99.6%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
    6. sub-neg99.6%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
    7. metadata-eval99.6%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
  3. Simplified99.6%

    \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
  4. Taylor expanded in x around 0 66.5%

    \[\leadsto \color{blue}{\left(\log y + \left(\log z + \log t \cdot \left(a - 0.5\right)\right)\right) - t} \]
  5. Taylor expanded in a around inf 74.5%

    \[\leadsto \color{blue}{a \cdot \log t} - t \]
  6. Step-by-step derivation
    1. *-commutative74.5%

      \[\leadsto \color{blue}{\log t \cdot a} - t \]
  7. Simplified74.5%

    \[\leadsto \color{blue}{\log t \cdot a} - t \]
  8. Final simplification74.5%

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

Alternative 14: 38.1% accurate, 156.5× 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. Step-by-step derivation
    1. associate--l+99.6%

      \[\leadsto \color{blue}{\left(\log \left(x + y\right) + \left(\log z - t\right)\right)} + \left(a - 0.5\right) \cdot \log t \]
    2. associate-+l+99.6%

      \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\left(\log z - t\right) + \left(a - 0.5\right) \cdot \log t\right)} \]
    3. +-commutative99.6%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(a - 0.5\right) \cdot \log t + \left(\log z - t\right)\right)} \]
    4. associate-+r-99.6%

      \[\leadsto \log \left(x + y\right) + \color{blue}{\left(\left(\left(a - 0.5\right) \cdot \log t + \log z\right) - t\right)} \]
    5. fma-def99.6%

      \[\leadsto \log \left(x + y\right) + \left(\color{blue}{\mathsf{fma}\left(a - 0.5, \log t, \log z\right)} - t\right) \]
    6. sub-neg99.6%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(\color{blue}{a + \left(-0.5\right)}, \log t, \log z\right) - t\right) \]
    7. metadata-eval99.6%

      \[\leadsto \log \left(x + y\right) + \left(\mathsf{fma}\left(a + \color{blue}{-0.5}, \log t, \log z\right) - t\right) \]
  3. Simplified99.6%

    \[\leadsto \color{blue}{\log \left(x + y\right) + \left(\mathsf{fma}\left(a + -0.5, \log t, \log z\right) - t\right)} \]
  4. Taylor expanded in t around inf 35.8%

    \[\leadsto \color{blue}{-1 \cdot t} \]
  5. Step-by-step derivation
    1. neg-mul-135.8%

      \[\leadsto \color{blue}{-t} \]
  6. Simplified35.8%

    \[\leadsto \color{blue}{-t} \]
  7. Final simplification35.8%

    \[\leadsto -t \]

Developer target: 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 2023275 
(FPCore (x y z t a)
  :name "Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2"
  :precision binary64

  :herbie-target
  (+ (log (+ x y)) (+ (- (log z) t) (* (- a 0.5) (log t))))

  (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))