bug500, discussion (missed optimization)

Percentage Accurate: 52.0% → 97.3%
Time: 12.3s
Alternatives: 7
Speedup: 19.3×

Specification

?
\[\begin{array}{l} \\ \log \left(\frac{\sinh x}{x}\right) \end{array} \]
(FPCore (x) :precision binary64 (log (/ (sinh x) x)))
double code(double x) {
	return log((sinh(x) / x));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

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

real(8) function code(x)
use fmin_fmax_functions
    real(8), intent (in) :: x
    code = log((sinh(x) / x))
end function
public static double code(double x) {
	return Math.log((Math.sinh(x) / x));
}
def code(x):
	return math.log((math.sinh(x) / x))
function code(x)
	return log(Float64(sinh(x) / x))
end
function tmp = code(x)
	tmp = log((sinh(x) / x));
end
code[x_] := N[Log[N[(N[Sinh[x], $MachinePrecision] / x), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\log \left(\frac{\sinh x}{x}\right)
\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 7 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: 52.0% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \log \left(\frac{\sinh x}{x}\right) \end{array} \]
(FPCore (x) :precision binary64 (log (/ (sinh x) x)))
double code(double x) {
	return log((sinh(x) / x));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

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

real(8) function code(x)
use fmin_fmax_functions
    real(8), intent (in) :: x
    code = log((sinh(x) / x))
end function
public static double code(double x) {
	return Math.log((Math.sinh(x) / x));
}
def code(x):
	return math.log((math.sinh(x) / x))
function code(x)
	return log(Float64(sinh(x) / x))
end
function tmp = code(x)
	tmp = log((sinh(x) / x));
end
code[x_] := N[Log[N[(N[Sinh[x], $MachinePrecision] / x), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\log \left(\frac{\sinh x}{x}\right)
\end{array}

Alternative 1: 97.3% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \left(\mathsf{fma}\left({x}^{4}, 3.08641975308642 \cdot 10^{-5}, -0.027777777777777776\right) \cdot \frac{x}{\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x - 0.16666666666666666}\right) \cdot x \end{array} \]
(FPCore (x)
 :precision binary64
 (*
  (*
   (fma (pow x 4.0) 3.08641975308642e-5 -0.027777777777777776)
   (/
    x
    (-
     (* (* (fma (* x x) 0.0003527336860670194 -0.005555555555555556) x) x)
     0.16666666666666666)))
  x))
double code(double x) {
	return (fma(pow(x, 4.0), 3.08641975308642e-5, -0.027777777777777776) * (x / (((fma((x * x), 0.0003527336860670194, -0.005555555555555556) * x) * x) - 0.16666666666666666))) * x;
}
function code(x)
	return Float64(Float64(fma((x ^ 4.0), 3.08641975308642e-5, -0.027777777777777776) * Float64(x / Float64(Float64(Float64(fma(Float64(x * x), 0.0003527336860670194, -0.005555555555555556) * x) * x) - 0.16666666666666666))) * x)
end
code[x_] := N[(N[(N[(N[Power[x, 4.0], $MachinePrecision] * 3.08641975308642e-5 + -0.027777777777777776), $MachinePrecision] * N[(x / N[(N[(N[(N[(N[(x * x), $MachinePrecision] * 0.0003527336860670194 + -0.005555555555555556), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] - 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]
\begin{array}{l}

\\
\left(\mathsf{fma}\left({x}^{4}, 3.08641975308642 \cdot 10^{-5}, -0.027777777777777776\right) \cdot \frac{x}{\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x - 0.16666666666666666}\right) \cdot x
\end{array}
Derivation
  1. Initial program 52.6%

    \[\log \left(\frac{\sinh x}{x}\right) \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{1}{2835} \cdot {x}^{2} - \frac{1}{180}\right)\right)} \]
  4. Step-by-step derivation
    1. Applied rewrites96.3%

      \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(0.0003527336860670194, x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
    2. Step-by-step derivation
      1. Applied rewrites96.4%

        \[\leadsto \frac{\mathsf{fma}\left({\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right)\right)}^{2}, {x}^{4}, -0.027777777777777776\right) \cdot x}{\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x - 0.16666666666666666} \cdot x \]
      2. Taylor expanded in x around 0

        \[\leadsto \frac{\mathsf{fma}\left(\frac{1}{32400}, {x}^{4}, \frac{-1}{36}\right) \cdot x}{\left(\mathsf{fma}\left(x \cdot x, \frac{1}{2835}, \frac{-1}{180}\right) \cdot x\right) \cdot x - \frac{1}{6}} \cdot x \]
      3. Step-by-step derivation
        1. Applied rewrites96.6%

          \[\leadsto \frac{\mathsf{fma}\left(3.08641975308642 \cdot 10^{-5}, {x}^{4}, -0.027777777777777776\right) \cdot x}{\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x - 0.16666666666666666} \cdot x \]
        2. Step-by-step derivation
          1. Applied rewrites96.6%

            \[\leadsto \left(\mathsf{fma}\left({x}^{4}, 3.08641975308642 \cdot 10^{-5}, -0.027777777777777776\right) \cdot \frac{x}{\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x - 0.16666666666666666}\right) \cdot x \]
          2. Add Preprocessing

          Alternative 2: 97.3% accurate, 3.2× speedup?

          \[\begin{array}{l} \\ \frac{\mathsf{fma}\left(3.08641975308642 \cdot 10^{-5} \cdot \left(x \cdot x\right), x \cdot x, -0.027777777777777776\right) \cdot x}{\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x - 0.16666666666666666} \cdot x \end{array} \]
          (FPCore (x)
           :precision binary64
           (*
            (/
             (* (fma (* 3.08641975308642e-5 (* x x)) (* x x) -0.027777777777777776) x)
             (-
              (* (* (fma (* x x) 0.0003527336860670194 -0.005555555555555556) x) x)
              0.16666666666666666))
            x))
          double code(double x) {
          	return ((fma((3.08641975308642e-5 * (x * x)), (x * x), -0.027777777777777776) * x) / (((fma((x * x), 0.0003527336860670194, -0.005555555555555556) * x) * x) - 0.16666666666666666)) * x;
          }
          
          function code(x)
          	return Float64(Float64(Float64(fma(Float64(3.08641975308642e-5 * Float64(x * x)), Float64(x * x), -0.027777777777777776) * x) / Float64(Float64(Float64(fma(Float64(x * x), 0.0003527336860670194, -0.005555555555555556) * x) * x) - 0.16666666666666666)) * x)
          end
          
          code[x_] := N[(N[(N[(N[(N[(3.08641975308642e-5 * N[(x * x), $MachinePrecision]), $MachinePrecision] * N[(x * x), $MachinePrecision] + -0.027777777777777776), $MachinePrecision] * x), $MachinePrecision] / N[(N[(N[(N[(N[(x * x), $MachinePrecision] * 0.0003527336860670194 + -0.005555555555555556), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] - 0.16666666666666666), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \frac{\mathsf{fma}\left(3.08641975308642 \cdot 10^{-5} \cdot \left(x \cdot x\right), x \cdot x, -0.027777777777777776\right) \cdot x}{\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x - 0.16666666666666666} \cdot x
          \end{array}
          
          Derivation
          1. Initial program 52.6%

            \[\log \left(\frac{\sinh x}{x}\right) \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{1}{2835} \cdot {x}^{2} - \frac{1}{180}\right)\right)} \]
          4. Step-by-step derivation
            1. Applied rewrites96.3%

              \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(0.0003527336860670194, x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
            2. Step-by-step derivation
              1. Applied rewrites96.4%

                \[\leadsto \frac{\mathsf{fma}\left({\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right)\right)}^{2}, {x}^{4}, -0.027777777777777776\right) \cdot x}{\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x - 0.16666666666666666} \cdot x \]
              2. Taylor expanded in x around 0

                \[\leadsto \frac{\mathsf{fma}\left(\frac{1}{32400}, {x}^{4}, \frac{-1}{36}\right) \cdot x}{\left(\mathsf{fma}\left(x \cdot x, \frac{1}{2835}, \frac{-1}{180}\right) \cdot x\right) \cdot x - \frac{1}{6}} \cdot x \]
              3. Step-by-step derivation
                1. Applied rewrites96.6%

                  \[\leadsto \frac{\mathsf{fma}\left(3.08641975308642 \cdot 10^{-5}, {x}^{4}, -0.027777777777777776\right) \cdot x}{\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x - 0.16666666666666666} \cdot x \]
                2. Step-by-step derivation
                  1. Applied rewrites96.6%

                    \[\leadsto \frac{\mathsf{fma}\left(3.08641975308642 \cdot 10^{-5} \cdot \left(x \cdot x\right), x \cdot x, -0.027777777777777776\right) \cdot x}{\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x - 0.16666666666666666} \cdot x \]
                  2. Add Preprocessing

                  Alternative 3: 97.1% accurate, 3.9× speedup?

                  \[\begin{array}{l} \\ \left(\frac{0.004629629629629629}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(4.899078973153048 \cdot 10^{-7}, x \cdot x, -2.792475014697237 \cdot 10^{-5}\right), x \cdot x, 0.000925925925925926\right), x \cdot x, 0.027777777777777776\right)} \cdot x\right) \cdot x \end{array} \]
                  (FPCore (x)
                   :precision binary64
                   (*
                    (*
                     (/
                      0.004629629629629629
                      (fma
                       (fma
                        (fma 4.899078973153048e-7 (* x x) -2.792475014697237e-5)
                        (* x x)
                        0.000925925925925926)
                       (* x x)
                       0.027777777777777776))
                     x)
                    x))
                  double code(double x) {
                  	return ((0.004629629629629629 / fma(fma(fma(4.899078973153048e-7, (x * x), -2.792475014697237e-5), (x * x), 0.000925925925925926), (x * x), 0.027777777777777776)) * x) * x;
                  }
                  
                  function code(x)
                  	return Float64(Float64(Float64(0.004629629629629629 / fma(fma(fma(4.899078973153048e-7, Float64(x * x), -2.792475014697237e-5), Float64(x * x), 0.000925925925925926), Float64(x * x), 0.027777777777777776)) * x) * x)
                  end
                  
                  code[x_] := N[(N[(N[(0.004629629629629629 / N[(N[(N[(4.899078973153048e-7 * N[(x * x), $MachinePrecision] + -2.792475014697237e-5), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.000925925925925926), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.027777777777777776), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \left(\frac{0.004629629629629629}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(4.899078973153048 \cdot 10^{-7}, x \cdot x, -2.792475014697237 \cdot 10^{-5}\right), x \cdot x, 0.000925925925925926\right), x \cdot x, 0.027777777777777776\right)} \cdot x\right) \cdot x
                  \end{array}
                  
                  Derivation
                  1. Initial program 52.6%

                    \[\log \left(\frac{\sinh x}{x}\right) \]
                  2. Add Preprocessing
                  3. Taylor expanded in x around 0

                    \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{1}{2835} + \frac{-1}{37800} \cdot {x}^{2}\right) - \frac{1}{180}\right)\right)} \]
                  4. Step-by-step derivation
                    1. Applied rewrites96.1%

                      \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-2.6455026455026456 \cdot 10^{-5}, x \cdot x, 0.0003527336860670194\right), x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
                    2. Step-by-step derivation
                      1. Applied rewrites96.1%

                        \[\leadsto \left(\frac{0.004629629629629629 - {\left(\left(-\mathsf{fma}\left(\mathsf{fma}\left(-2.6455026455026456 \cdot 10^{-5}, x \cdot x, 0.0003527336860670194\right), x \cdot x, -0.005555555555555556\right)\right) \cdot \left(x \cdot x\right)\right)}^{3}}{0.027777777777777776 + \mathsf{fma}\left(\left(-\mathsf{fma}\left(\mathsf{fma}\left(-2.6455026455026456 \cdot 10^{-5}, x \cdot x, 0.0003527336860670194\right), x \cdot x, -0.005555555555555556\right)\right) \cdot \left(x \cdot x\right), \left(-\mathsf{fma}\left(\mathsf{fma}\left(-2.6455026455026456 \cdot 10^{-5}, x \cdot x, 0.0003527336860670194\right), x \cdot x, -0.005555555555555556\right)\right) \cdot \left(x \cdot x\right), 0.16666666666666666 \cdot \left(\left(-\mathsf{fma}\left(\mathsf{fma}\left(-2.6455026455026456 \cdot 10^{-5}, x \cdot x, 0.0003527336860670194\right), x \cdot x, -0.005555555555555556\right)\right) \cdot \left(x \cdot x\right)\right)\right)} \cdot x\right) \cdot x \]
                      2. Taylor expanded in x around 0

                        \[\leadsto \left(\frac{\frac{1}{216} - {\left(\left(-\mathsf{fma}\left(\mathsf{fma}\left(\frac{-1}{37800}, x \cdot x, \frac{1}{2835}\right), x \cdot x, \frac{-1}{180}\right)\right) \cdot \left(x \cdot x\right)\right)}^{3}}{\frac{1}{36} + {x}^{2} \cdot \left(\frac{1}{1080} + {x}^{2} \cdot \left(\frac{1}{2041200} \cdot {x}^{2} - \frac{19}{680400}\right)\right)} \cdot x\right) \cdot x \]
                      3. Step-by-step derivation
                        1. Applied rewrites96.2%

                          \[\leadsto \left(\frac{0.004629629629629629 - {\left(\left(-\mathsf{fma}\left(\mathsf{fma}\left(-2.6455026455026456 \cdot 10^{-5}, x \cdot x, 0.0003527336860670194\right), x \cdot x, -0.005555555555555556\right)\right) \cdot \left(x \cdot x\right)\right)}^{3}}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(4.899078973153048 \cdot 10^{-7}, x \cdot x, -2.792475014697237 \cdot 10^{-5}\right), x \cdot x, 0.000925925925925926\right), x \cdot x, 0.027777777777777776\right)} \cdot x\right) \cdot x \]
                        2. Taylor expanded in x around 0

                          \[\leadsto \left(\frac{\frac{1}{216}}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{2041200}, x \cdot x, \frac{-19}{680400}\right), x \cdot x, \frac{1}{1080}\right), x \cdot x, \frac{1}{36}\right)} \cdot x\right) \cdot x \]
                        3. Step-by-step derivation
                          1. Applied rewrites96.4%

                            \[\leadsto \left(\frac{0.004629629629629629}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(4.899078973153048 \cdot 10^{-7}, x \cdot x, -2.792475014697237 \cdot 10^{-5}\right), x \cdot x, 0.000925925925925926\right), x \cdot x, 0.027777777777777776\right)} \cdot x\right) \cdot x \]
                          2. Add Preprocessing

                          Alternative 4: 97.1% accurate, 5.6× speedup?

                          \[\begin{array}{l} \\ \mathsf{fma}\left(\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x, x, 0.16666666666666666 \cdot x\right) \cdot x \end{array} \]
                          (FPCore (x)
                           :precision binary64
                           (*
                            (fma
                             (* (* (fma (* x x) 0.0003527336860670194 -0.005555555555555556) x) x)
                             x
                             (* 0.16666666666666666 x))
                            x))
                          double code(double x) {
                          	return fma(((fma((x * x), 0.0003527336860670194, -0.005555555555555556) * x) * x), x, (0.16666666666666666 * x)) * x;
                          }
                          
                          function code(x)
                          	return Float64(fma(Float64(Float64(fma(Float64(x * x), 0.0003527336860670194, -0.005555555555555556) * x) * x), x, Float64(0.16666666666666666 * x)) * x)
                          end
                          
                          code[x_] := N[(N[(N[(N[(N[(N[(x * x), $MachinePrecision] * 0.0003527336860670194 + -0.005555555555555556), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] * x + N[(0.16666666666666666 * x), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]
                          
                          \begin{array}{l}
                          
                          \\
                          \mathsf{fma}\left(\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x, x, 0.16666666666666666 \cdot x\right) \cdot x
                          \end{array}
                          
                          Derivation
                          1. Initial program 52.6%

                            \[\log \left(\frac{\sinh x}{x}\right) \]
                          2. Add Preprocessing
                          3. Taylor expanded in x around 0

                            \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{1}{2835} \cdot {x}^{2} - \frac{1}{180}\right)\right)} \]
                          4. Step-by-step derivation
                            1. Applied rewrites96.3%

                              \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(0.0003527336860670194, x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
                            2. Step-by-step derivation
                              1. Applied rewrites96.3%

                                \[\leadsto \mathsf{fma}\left(\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x, x, 0.16666666666666666 \cdot x\right) \cdot x \]
                              2. Add Preprocessing

                              Alternative 5: 97.1% accurate, 6.4× speedup?

                              \[\begin{array}{l} \\ \left(\mathsf{fma}\left(\mathsf{fma}\left(0.0003527336860670194, x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x \end{array} \]
                              (FPCore (x)
                               :precision binary64
                               (*
                                (*
                                 (fma
                                  (fma 0.0003527336860670194 (* x x) -0.005555555555555556)
                                  (* x x)
                                  0.16666666666666666)
                                 x)
                                x))
                              double code(double x) {
                              	return (fma(fma(0.0003527336860670194, (x * x), -0.005555555555555556), (x * x), 0.16666666666666666) * x) * x;
                              }
                              
                              function code(x)
                              	return Float64(Float64(fma(fma(0.0003527336860670194, Float64(x * x), -0.005555555555555556), Float64(x * x), 0.16666666666666666) * x) * x)
                              end
                              
                              code[x_] := N[(N[(N[(N[(0.0003527336860670194 * N[(x * x), $MachinePrecision] + -0.005555555555555556), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.16666666666666666), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision]
                              
                              \begin{array}{l}
                              
                              \\
                              \left(\mathsf{fma}\left(\mathsf{fma}\left(0.0003527336860670194, x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x
                              \end{array}
                              
                              Derivation
                              1. Initial program 52.6%

                                \[\log \left(\frac{\sinh x}{x}\right) \]
                              2. Add Preprocessing
                              3. Taylor expanded in x around 0

                                \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left(\frac{1}{2835} \cdot {x}^{2} - \frac{1}{180}\right)\right)} \]
                              4. Step-by-step derivation
                                1. Applied rewrites96.3%

                                  \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(0.0003527336860670194, x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
                                2. Add Preprocessing

                                Alternative 6: 96.6% accurate, 19.3× speedup?

                                \[\begin{array}{l} \\ \left(0.16666666666666666 \cdot x\right) \cdot x \end{array} \]
                                (FPCore (x) :precision binary64 (* (* 0.16666666666666666 x) x))
                                double code(double x) {
                                	return (0.16666666666666666 * x) * x;
                                }
                                
                                module fmin_fmax_functions
                                    implicit none
                                    private
                                    public fmax
                                    public fmin
                                
                                    interface fmax
                                        module procedure fmax88
                                        module procedure fmax44
                                        module procedure fmax84
                                        module procedure fmax48
                                    end interface
                                    interface fmin
                                        module procedure fmin88
                                        module procedure fmin44
                                        module procedure fmin84
                                        module procedure fmin48
                                    end interface
                                contains
                                    real(8) function fmax88(x, y) result (res)
                                        real(8), intent (in) :: x
                                        real(8), intent (in) :: y
                                        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                    end function
                                    real(4) function fmax44(x, y) result (res)
                                        real(4), intent (in) :: x
                                        real(4), intent (in) :: y
                                        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                    end function
                                    real(8) function fmax84(x, y) result(res)
                                        real(8), intent (in) :: x
                                        real(4), intent (in) :: y
                                        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                    end function
                                    real(8) function fmax48(x, y) result(res)
                                        real(4), intent (in) :: x
                                        real(8), intent (in) :: y
                                        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                    end function
                                    real(8) function fmin88(x, y) result (res)
                                        real(8), intent (in) :: x
                                        real(8), intent (in) :: y
                                        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                    end function
                                    real(4) function fmin44(x, y) result (res)
                                        real(4), intent (in) :: x
                                        real(4), intent (in) :: y
                                        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                    end function
                                    real(8) function fmin84(x, y) result(res)
                                        real(8), intent (in) :: x
                                        real(4), intent (in) :: y
                                        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                    end function
                                    real(8) function fmin48(x, y) result(res)
                                        real(4), intent (in) :: x
                                        real(8), intent (in) :: y
                                        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                    end function
                                end module
                                
                                real(8) function code(x)
                                use fmin_fmax_functions
                                    real(8), intent (in) :: x
                                    code = (0.16666666666666666d0 * x) * x
                                end function
                                
                                public static double code(double x) {
                                	return (0.16666666666666666 * x) * x;
                                }
                                
                                def code(x):
                                	return (0.16666666666666666 * x) * x
                                
                                function code(x)
                                	return Float64(Float64(0.16666666666666666 * x) * x)
                                end
                                
                                function tmp = code(x)
                                	tmp = (0.16666666666666666 * x) * x;
                                end
                                
                                code[x_] := N[(N[(0.16666666666666666 * x), $MachinePrecision] * x), $MachinePrecision]
                                
                                \begin{array}{l}
                                
                                \\
                                \left(0.16666666666666666 \cdot x\right) \cdot x
                                \end{array}
                                
                                Derivation
                                1. Initial program 52.6%

                                  \[\log \left(\frac{\sinh x}{x}\right) \]
                                2. Add Preprocessing
                                3. Taylor expanded in x around 0

                                  \[\leadsto \color{blue}{{x}^{2} \cdot \left(\frac{1}{6} + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{1}{2835} + \frac{-1}{37800} \cdot {x}^{2}\right) - \frac{1}{180}\right)\right)} \]
                                4. Step-by-step derivation
                                  1. Applied rewrites96.1%

                                    \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-2.6455026455026456 \cdot 10^{-5}, x \cdot x, 0.0003527336860670194\right), x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
                                  2. Taylor expanded in x around 0

                                    \[\leadsto \left(\frac{1}{6} \cdot x\right) \cdot x \]
                                  3. Step-by-step derivation
                                    1. Applied rewrites95.9%

                                      \[\leadsto \left(0.16666666666666666 \cdot x\right) \cdot x \]
                                    2. Add Preprocessing

                                    Alternative 7: 96.5% accurate, 19.3× speedup?

                                    \[\begin{array}{l} \\ \left(x \cdot x\right) \cdot 0.16666666666666666 \end{array} \]
                                    (FPCore (x) :precision binary64 (* (* x x) 0.16666666666666666))
                                    double code(double x) {
                                    	return (x * x) * 0.16666666666666666;
                                    }
                                    
                                    module fmin_fmax_functions
                                        implicit none
                                        private
                                        public fmax
                                        public fmin
                                    
                                        interface fmax
                                            module procedure fmax88
                                            module procedure fmax44
                                            module procedure fmax84
                                            module procedure fmax48
                                        end interface
                                        interface fmin
                                            module procedure fmin88
                                            module procedure fmin44
                                            module procedure fmin84
                                            module procedure fmin48
                                        end interface
                                    contains
                                        real(8) function fmax88(x, y) result (res)
                                            real(8), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                        end function
                                        real(4) function fmax44(x, y) result (res)
                                            real(4), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
                                        end function
                                        real(8) function fmax84(x, y) result(res)
                                            real(8), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
                                        end function
                                        real(8) function fmax48(x, y) result(res)
                                            real(4), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
                                        end function
                                        real(8) function fmin88(x, y) result (res)
                                            real(8), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                        end function
                                        real(4) function fmin44(x, y) result (res)
                                            real(4), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
                                        end function
                                        real(8) function fmin84(x, y) result(res)
                                            real(8), intent (in) :: x
                                            real(4), intent (in) :: y
                                            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
                                        end function
                                        real(8) function fmin48(x, y) result(res)
                                            real(4), intent (in) :: x
                                            real(8), intent (in) :: y
                                            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
                                        end function
                                    end module
                                    
                                    real(8) function code(x)
                                    use fmin_fmax_functions
                                        real(8), intent (in) :: x
                                        code = (x * x) * 0.16666666666666666d0
                                    end function
                                    
                                    public static double code(double x) {
                                    	return (x * x) * 0.16666666666666666;
                                    }
                                    
                                    def code(x):
                                    	return (x * x) * 0.16666666666666666
                                    
                                    function code(x)
                                    	return Float64(Float64(x * x) * 0.16666666666666666)
                                    end
                                    
                                    function tmp = code(x)
                                    	tmp = (x * x) * 0.16666666666666666;
                                    end
                                    
                                    code[x_] := N[(N[(x * x), $MachinePrecision] * 0.16666666666666666), $MachinePrecision]
                                    
                                    \begin{array}{l}
                                    
                                    \\
                                    \left(x \cdot x\right) \cdot 0.16666666666666666
                                    \end{array}
                                    
                                    Derivation
                                    1. Initial program 52.6%

                                      \[\log \left(\frac{\sinh x}{x}\right) \]
                                    2. Add Preprocessing
                                    3. Taylor expanded in x around 0

                                      \[\leadsto \color{blue}{\frac{1}{6} \cdot {x}^{2}} \]
                                    4. Step-by-step derivation
                                      1. Applied rewrites95.9%

                                        \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot 0.16666666666666666} \]
                                      2. Add Preprocessing

                                      Developer Target 1: 97.9% accurate, 1.0× speedup?

                                      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\left|x\right| < 0.085:\\ \;\;\;\;\left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-2.6455026455026456 \cdot 10^{-5}, x \cdot x, 0.0003527336860670194\right), x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right)\\ \mathbf{else}:\\ \;\;\;\;\log \left(\frac{\sinh x}{x}\right)\\ \end{array} \end{array} \]
                                      (FPCore (x)
                                       :precision binary64
                                       (if (< (fabs x) 0.085)
                                         (*
                                          (* x x)
                                          (fma
                                           (fma
                                            (fma -2.6455026455026456e-5 (* x x) 0.0003527336860670194)
                                            (* x x)
                                            -0.005555555555555556)
                                           (* x x)
                                           0.16666666666666666))
                                         (log (/ (sinh x) x))))
                                      double code(double x) {
                                      	double tmp;
                                      	if (fabs(x) < 0.085) {
                                      		tmp = (x * x) * fma(fma(fma(-2.6455026455026456e-5, (x * x), 0.0003527336860670194), (x * x), -0.005555555555555556), (x * x), 0.16666666666666666);
                                      	} else {
                                      		tmp = log((sinh(x) / x));
                                      	}
                                      	return tmp;
                                      }
                                      
                                      function code(x)
                                      	tmp = 0.0
                                      	if (abs(x) < 0.085)
                                      		tmp = Float64(Float64(x * x) * fma(fma(fma(-2.6455026455026456e-5, Float64(x * x), 0.0003527336860670194), Float64(x * x), -0.005555555555555556), Float64(x * x), 0.16666666666666666));
                                      	else
                                      		tmp = log(Float64(sinh(x) / x));
                                      	end
                                      	return tmp
                                      end
                                      
                                      code[x_] := If[Less[N[Abs[x], $MachinePrecision], 0.085], N[(N[(x * x), $MachinePrecision] * N[(N[(N[(-2.6455026455026456e-5 * N[(x * x), $MachinePrecision] + 0.0003527336860670194), $MachinePrecision] * N[(x * x), $MachinePrecision] + -0.005555555555555556), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.16666666666666666), $MachinePrecision]), $MachinePrecision], N[Log[N[(N[Sinh[x], $MachinePrecision] / x), $MachinePrecision]], $MachinePrecision]]
                                      
                                      \begin{array}{l}
                                      
                                      \\
                                      \begin{array}{l}
                                      \mathbf{if}\;\left|x\right| < 0.085:\\
                                      \;\;\;\;\left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-2.6455026455026456 \cdot 10^{-5}, x \cdot x, 0.0003527336860670194\right), x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right)\\
                                      
                                      \mathbf{else}:\\
                                      \;\;\;\;\log \left(\frac{\sinh x}{x}\right)\\
                                      
                                      
                                      \end{array}
                                      \end{array}
                                      

                                      Reproduce

                                      ?
                                      herbie shell --seed 2025018 
                                      (FPCore (x)
                                        :name "bug500, discussion (missed optimization)"
                                        :precision binary64
                                      
                                        :alt
                                        (! :herbie-platform default (if (< (fabs x) 17/200) (let ((x2 (* x x))) (* x2 (fma (fma (fma -1/37800 x2 1/2835) x2 -1/180) x2 1/6))) (log (/ (sinh x) x))))
                                      
                                        (log (/ (sinh x) x)))