bug500, discussion (missed optimization)

Percentage Accurate: 54.0% → 96.9%
Time: 12.9s
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: 54.0% 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: 96.9% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(\mathsf{fma}\left(0.0003527336860670194, x \cdot x, -0.005555555555555556\right) \cdot x\right) \cdot x\\ t_1 := t\_0 - 0.16666666666666666\\ \frac{{t\_0}^{2} \cdot t\_1 - t\_1 \cdot 0.027777777777777776}{t\_1 \cdot t\_1} \cdot \left(x \cdot x\right) \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0
         (* (* (fma 0.0003527336860670194 (* x x) -0.005555555555555556) x) x))
        (t_1 (- t_0 0.16666666666666666)))
   (*
    (/ (- (* (pow t_0 2.0) t_1) (* t_1 0.027777777777777776)) (* t_1 t_1))
    (* x x))))
double code(double x) {
	double t_0 = (fma(0.0003527336860670194, (x * x), -0.005555555555555556) * x) * x;
	double t_1 = t_0 - 0.16666666666666666;
	return (((pow(t_0, 2.0) * t_1) - (t_1 * 0.027777777777777776)) / (t_1 * t_1)) * (x * x);
}
function code(x)
	t_0 = Float64(Float64(fma(0.0003527336860670194, Float64(x * x), -0.005555555555555556) * x) * x)
	t_1 = Float64(t_0 - 0.16666666666666666)
	return Float64(Float64(Float64(Float64((t_0 ^ 2.0) * t_1) - Float64(t_1 * 0.027777777777777776)) / Float64(t_1 * t_1)) * Float64(x * x))
end
code[x_] := Block[{t$95$0 = N[(N[(N[(0.0003527336860670194 * N[(x * x), $MachinePrecision] + -0.005555555555555556), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision]}, Block[{t$95$1 = N[(t$95$0 - 0.16666666666666666), $MachinePrecision]}, N[(N[(N[(N[(N[Power[t$95$0, 2.0], $MachinePrecision] * t$95$1), $MachinePrecision] - N[(t$95$1 * 0.027777777777777776), $MachinePrecision]), $MachinePrecision] / N[(t$95$1 * t$95$1), $MachinePrecision]), $MachinePrecision] * N[(x * x), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(\mathsf{fma}\left(0.0003527336860670194, x \cdot x, -0.005555555555555556\right) \cdot x\right) \cdot x\\
t_1 := t\_0 - 0.16666666666666666\\
\frac{{t\_0}^{2} \cdot t\_1 - t\_1 \cdot 0.027777777777777776}{t\_1 \cdot t\_1} \cdot \left(x \cdot x\right)
\end{array}
\end{array}
Derivation
  1. Initial program 52.7%

    \[\log \left(\frac{\sinh x}{x}\right) \]
  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 rewrites96.6%

      \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(0.0003527336860670194, x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
    2. Step-by-step derivation
      1. Applied rewrites96.6%

        \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot \color{blue}{\left(x \cdot x\right)} \]
      2. Step-by-step derivation
        1. Applied rewrites96.7%

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

        Alternative 2: 74.1% accurate, 4.0× speedup?

        \[\begin{array}{l} \\ \mathsf{fma}\left(\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x, x, \sqrt{0.027777777777777776 \cdot \left(x \cdot x\right)}\right) \cdot x \end{array} \]
        (FPCore (x)
         :precision binary64
         (*
          (fma
           (* (* (fma (* x x) 0.0003527336860670194 -0.005555555555555556) x) x)
           x
           (sqrt (* 0.027777777777777776 (* x x))))
          x))
        double code(double x) {
        	return fma(((fma((x * x), 0.0003527336860670194, -0.005555555555555556) * x) * x), x, sqrt((0.027777777777777776 * (x * x)))) * x;
        }
        
        function code(x)
        	return Float64(fma(Float64(Float64(fma(Float64(x * x), 0.0003527336860670194, -0.005555555555555556) * x) * x), x, sqrt(Float64(0.027777777777777776 * Float64(x * 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[Sqrt[N[(0.027777777777777776 * N[(x * x), $MachinePrecision]), $MachinePrecision]], $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, \sqrt{0.027777777777777776 \cdot \left(x \cdot x\right)}\right) \cdot x
        \end{array}
        
        Derivation
        1. Initial program 52.7%

          \[\log \left(\frac{\sinh x}{x}\right) \]
        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 rewrites96.6%

            \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(0.0003527336860670194, x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
          2. Step-by-step derivation
            1. Applied rewrites96.6%

              \[\leadsto \mathsf{fma}\left(\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x, x, 0.16666666666666666 \cdot x\right) \cdot x \]
            2. Step-by-step derivation
              1. Applied rewrites74.4%

                \[\leadsto \mathsf{fma}\left(\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right) \cdot x\right) \cdot x, x, \sqrt{0.027777777777777776 \cdot \left(x \cdot x\right)}\right) \cdot x \]
              2. Add Preprocessing

              Alternative 3: 96.9% accurate, 6.4× speedup?

              \[\begin{array}{l} \\ \mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot \left(x \cdot x\right) \end{array} \]
              (FPCore (x)
               :precision binary64
               (*
                (fma
                 (fma (* x x) 0.0003527336860670194 -0.005555555555555556)
                 (* x x)
                 0.16666666666666666)
                (* x x)))
              double code(double x) {
              	return fma(fma((x * x), 0.0003527336860670194, -0.005555555555555556), (x * x), 0.16666666666666666) * (x * x);
              }
              
              function code(x)
              	return Float64(fma(fma(Float64(x * x), 0.0003527336860670194, -0.005555555555555556), Float64(x * x), 0.16666666666666666) * Float64(x * x))
              end
              
              code[x_] := N[(N[(N[(N[(x * x), $MachinePrecision] * 0.0003527336860670194 + -0.005555555555555556), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.16666666666666666), $MachinePrecision] * N[(x * x), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, 0.0003527336860670194, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot \left(x \cdot x\right)
              \end{array}
              
              Derivation
              1. Initial program 52.7%

                \[\log \left(\frac{\sinh x}{x}\right) \]
              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 rewrites96.6%

                  \[\leadsto \color{blue}{\left(\mathsf{fma}\left(\mathsf{fma}\left(0.0003527336860670194, x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x} \]
                2. Step-by-step derivation
                  1. Applied rewrites96.6%

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

                  Alternative 4: 96.9% 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 52.7%

                    \[\log \left(\frac{\sinh x}{x}\right) \]
                  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 rewrites96.6%

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

                    Alternative 5: 96.5% accurate, 9.6× speedup?

                    \[\begin{array}{l} \\ \mathsf{fma}\left(-0.005555555555555556, x \cdot x, 0.16666666666666666\right) \cdot \left(x \cdot x\right) \end{array} \]
                    (FPCore (x)
                     :precision binary64
                     (* (fma -0.005555555555555556 (* x x) 0.16666666666666666) (* x x)))
                    double code(double x) {
                    	return fma(-0.005555555555555556, (x * x), 0.16666666666666666) * (x * x);
                    }
                    
                    function code(x)
                    	return Float64(fma(-0.005555555555555556, Float64(x * x), 0.16666666666666666) * Float64(x * x))
                    end
                    
                    code[x_] := N[(N[(-0.005555555555555556 * N[(x * x), $MachinePrecision] + 0.16666666666666666), $MachinePrecision] * N[(x * x), $MachinePrecision]), $MachinePrecision]
                    
                    \begin{array}{l}
                    
                    \\
                    \mathsf{fma}\left(-0.005555555555555556, x \cdot x, 0.16666666666666666\right) \cdot \left(x \cdot x\right)
                    \end{array}
                    
                    Derivation
                    1. Initial program 52.7%

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

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

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

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

                        Alternative 6: 96.5% accurate, 9.6× speedup?

                        \[\begin{array}{l} \\ \left(\mathsf{fma}\left(-0.005555555555555556, x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x \end{array} \]
                        (FPCore (x)
                         :precision binary64
                         (* (* (fma -0.005555555555555556 (* x x) 0.16666666666666666) x) x))
                        double code(double x) {
                        	return (fma(-0.005555555555555556, (x * x), 0.16666666666666666) * x) * x;
                        }
                        
                        function code(x)
                        	return Float64(Float64(fma(-0.005555555555555556, Float64(x * x), 0.16666666666666666) * x) * x)
                        end
                        
                        code[x_] := N[(N[(N[(-0.005555555555555556 * N[(x * x), $MachinePrecision] + 0.16666666666666666), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision]
                        
                        \begin{array}{l}
                        
                        \\
                        \left(\mathsf{fma}\left(-0.005555555555555556, x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x
                        \end{array}
                        
                        Derivation
                        1. Initial program 52.7%

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

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

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

                          Alternative 7: 96.4% 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 52.7%

                            \[\log \left(\frac{\sinh x}{x}\right) \]
                          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 rewrites96.1%

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

                            Developer Target 1: 97.8% 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 2025026 
                            (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)))