Trigonometry B

Percentage Accurate: 99.5% → 99.7%
Time: 3.8s
Alternatives: 15
Speedup: 1.0×

Specification

?
\[\begin{array}{l} t_0 := \tan x \cdot \tan x\\ \frac{1 - t\_0}{1 + t\_0} \end{array} \]
(FPCore (x)
  :precision binary64
  (let* ((t_0 (* (tan x) (tan x)))) (/ (- 1.0 t_0) (+ 1.0 t_0))))
double code(double x) {
	double t_0 = tan(x) * tan(x);
	return (1.0 - t_0) / (1.0 + t_0);
}
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
    real(8) :: t_0
    t_0 = tan(x) * tan(x)
    code = (1.0d0 - t_0) / (1.0d0 + t_0)
end function
public static double code(double x) {
	double t_0 = Math.tan(x) * Math.tan(x);
	return (1.0 - t_0) / (1.0 + t_0);
}
def code(x):
	t_0 = math.tan(x) * math.tan(x)
	return (1.0 - t_0) / (1.0 + t_0)
function code(x)
	t_0 = Float64(tan(x) * tan(x))
	return Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0))
end
function tmp = code(x)
	t_0 = tan(x) * tan(x);
	tmp = (1.0 - t_0) / (1.0 + t_0);
end
code[x_] := Block[{t$95$0 = N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]}, N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
t_0 := \tan x \cdot \tan x\\
\frac{1 - t\_0}{1 + t\_0}
\end{array}

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 15 alternatives:

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

Initial Program: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} t_0 := \tan x \cdot \tan x\\ \frac{1 - t\_0}{1 + t\_0} \end{array} \]
(FPCore (x)
  :precision binary64
  (let* ((t_0 (* (tan x) (tan x)))) (/ (- 1.0 t_0) (+ 1.0 t_0))))
double code(double x) {
	double t_0 = tan(x) * tan(x);
	return (1.0 - t_0) / (1.0 + t_0);
}
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
    real(8) :: t_0
    t_0 = tan(x) * tan(x)
    code = (1.0d0 - t_0) / (1.0d0 + t_0)
end function
public static double code(double x) {
	double t_0 = Math.tan(x) * Math.tan(x);
	return (1.0 - t_0) / (1.0 + t_0);
}
def code(x):
	t_0 = math.tan(x) * math.tan(x)
	return (1.0 - t_0) / (1.0 + t_0)
function code(x)
	t_0 = Float64(tan(x) * tan(x))
	return Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0))
end
function tmp = code(x)
	t_0 = tan(x) * tan(x);
	tmp = (1.0 - t_0) / (1.0 + t_0);
end
code[x_] := Block[{t$95$0 = N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]}, N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
t_0 := \tan x \cdot \tan x\\
\frac{1 - t\_0}{1 + t\_0}
\end{array}

Alternative 1: 99.7% accurate, 0.9× speedup?

\[\begin{array}{l} t_0 := \cos \left(x + x\right)\\ \frac{t\_0 \cdot \frac{1}{\mathsf{fma}\left(t\_0, 0.5, 0.5\right)}}{1 + \frac{\mathsf{fma}\left(0.5, t\_0, -0.5\right)}{\mathsf{fma}\left(-0.5, t\_0, -0.5\right)}} \end{array} \]
(FPCore (x)
  :precision binary64
  (let* ((t_0 (cos (+ x x))))
  (/
   (* t_0 (/ 1.0 (fma t_0 0.5 0.5)))
   (+ 1.0 (/ (fma 0.5 t_0 -0.5) (fma -0.5 t_0 -0.5))))))
double code(double x) {
	double t_0 = cos((x + x));
	return (t_0 * (1.0 / fma(t_0, 0.5, 0.5))) / (1.0 + (fma(0.5, t_0, -0.5) / fma(-0.5, t_0, -0.5)));
}
function code(x)
	t_0 = cos(Float64(x + x))
	return Float64(Float64(t_0 * Float64(1.0 / fma(t_0, 0.5, 0.5))) / Float64(1.0 + Float64(fma(0.5, t_0, -0.5) / fma(-0.5, t_0, -0.5))))
end
code[x_] := Block[{t$95$0 = N[Cos[N[(x + x), $MachinePrecision]], $MachinePrecision]}, N[(N[(t$95$0 * N[(1.0 / N[(t$95$0 * 0.5 + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[(N[(0.5 * t$95$0 + -0.5), $MachinePrecision] / N[(-0.5 * t$95$0 + -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
t_0 := \cos \left(x + x\right)\\
\frac{t\_0 \cdot \frac{1}{\mathsf{fma}\left(t\_0, 0.5, 0.5\right)}}{1 + \frac{\mathsf{fma}\left(0.5, t\_0, -0.5\right)}{\mathsf{fma}\left(-0.5, t\_0, -0.5\right)}}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}}{1 + \tan x \cdot \tan x} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}}{1 + \tan x \cdot \tan x} \]
    6. frac-timesN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
    7. lower-/.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
  3. Applied rewrites98.9%

    \[\leadsto \frac{1 - \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(x + x\right)}{0.5 + 0.5 \cdot \cos \left(x + x\right)}}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \color{blue}{\tan x} \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
    6. frac-timesN/A

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

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}} \]
  5. Applied rewrites99.5%

    \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(x + x\right)}{0.5 + 0.5 \cdot \cos \left(x + x\right)}}{1 + \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(x + x\right)}{0.5 + 0.5 \cdot \cos \left(x + x\right)}}} \]
  6. Applied rewrites99.7%

    \[\leadsto \frac{\color{blue}{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}}{1 + \frac{0.5 - 0.5 \cdot \cos \left(x + x\right)}{0.5 + 0.5 \cdot \cos \left(x + x\right)}} \]
  7. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \color{blue}{\frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}} \]
    2. lift--.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    3. lift-*.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(x + x\right)}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    4. lift-cos.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(x + x\right)}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    5. lift-+.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(x + x\right)}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    6. count-2N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    7. sqr-sin-a-revN/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\color{blue}{\sin x \cdot \sin x}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    8. lift-sin.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\color{blue}{\sin x} \cdot \sin x}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    9. lift-sin.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\sin x \cdot \color{blue}{\sin x}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    10. unpow2N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    11. lift-pow.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    12. frac-2neg-revN/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \color{blue}{\frac{\mathsf{neg}\left({\sin x}^{2}\right)}{\mathsf{neg}\left(\left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)\right)\right)}}} \]
    13. lower-/.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \color{blue}{\frac{\mathsf{neg}\left({\sin x}^{2}\right)}{\mathsf{neg}\left(\left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)\right)\right)}}} \]
  8. Applied rewrites99.7%

    \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}{1 + \color{blue}{\frac{\mathsf{fma}\left(0.5, \cos \left(x + x\right), -0.5\right)}{\mathsf{fma}\left(-0.5, \cos \left(x + x\right), -0.5\right)}}} \]
  9. Add Preprocessing

Alternative 2: 99.6% accurate, 0.9× speedup?

\[\begin{array}{l} t_0 := \cos \left(x + x\right)\\ \frac{\frac{t\_0}{\mathsf{fma}\left(0.5, t\_0, 0.5\right)}}{1 + \frac{\mathsf{fma}\left(0.5, t\_0, -0.5\right)}{\mathsf{fma}\left(-0.5, t\_0, -0.5\right)}} \end{array} \]
(FPCore (x)
  :precision binary64
  (let* ((t_0 (cos (+ x x))))
  (/
   (/ t_0 (fma 0.5 t_0 0.5))
   (+ 1.0 (/ (fma 0.5 t_0 -0.5) (fma -0.5 t_0 -0.5))))))
double code(double x) {
	double t_0 = cos((x + x));
	return (t_0 / fma(0.5, t_0, 0.5)) / (1.0 + (fma(0.5, t_0, -0.5) / fma(-0.5, t_0, -0.5)));
}
function code(x)
	t_0 = cos(Float64(x + x))
	return Float64(Float64(t_0 / fma(0.5, t_0, 0.5)) / Float64(1.0 + Float64(fma(0.5, t_0, -0.5) / fma(-0.5, t_0, -0.5))))
end
code[x_] := Block[{t$95$0 = N[Cos[N[(x + x), $MachinePrecision]], $MachinePrecision]}, N[(N[(t$95$0 / N[(0.5 * t$95$0 + 0.5), $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[(N[(0.5 * t$95$0 + -0.5), $MachinePrecision] / N[(-0.5 * t$95$0 + -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
t_0 := \cos \left(x + x\right)\\
\frac{\frac{t\_0}{\mathsf{fma}\left(0.5, t\_0, 0.5\right)}}{1 + \frac{\mathsf{fma}\left(0.5, t\_0, -0.5\right)}{\mathsf{fma}\left(-0.5, t\_0, -0.5\right)}}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}}{1 + \tan x \cdot \tan x} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}}{1 + \tan x \cdot \tan x} \]
    6. frac-timesN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
    7. lower-/.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
  3. Applied rewrites98.9%

    \[\leadsto \frac{1 - \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(x + x\right)}{0.5 + 0.5 \cdot \cos \left(x + x\right)}}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \color{blue}{\tan x} \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
    6. frac-timesN/A

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

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}{1 + \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}} \]
  5. Applied rewrites99.5%

    \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(x + x\right)}{0.5 + 0.5 \cdot \cos \left(x + x\right)}}{1 + \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(x + x\right)}{0.5 + 0.5 \cdot \cos \left(x + x\right)}}} \]
  6. Applied rewrites99.7%

    \[\leadsto \frac{\color{blue}{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}}{1 + \frac{0.5 - 0.5 \cdot \cos \left(x + x\right)}{0.5 + 0.5 \cdot \cos \left(x + x\right)}} \]
  7. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \color{blue}{\frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}} \]
    2. lift--.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(x + x\right)}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    3. lift-*.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(x + x\right)}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    4. lift-cos.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(x + x\right)}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    5. lift-+.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(x + x\right)}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    6. count-2N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    7. sqr-sin-a-revN/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\color{blue}{\sin x \cdot \sin x}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    8. lift-sin.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\color{blue}{\sin x} \cdot \sin x}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    9. lift-sin.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\sin x \cdot \color{blue}{\sin x}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    10. unpow2N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    11. lift-pow.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}} \]
    12. frac-2neg-revN/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \color{blue}{\frac{\mathsf{neg}\left({\sin x}^{2}\right)}{\mathsf{neg}\left(\left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)\right)\right)}}} \]
    13. lower-/.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1 + \color{blue}{\frac{\mathsf{neg}\left({\sin x}^{2}\right)}{\mathsf{neg}\left(\left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)\right)\right)}}} \]
  8. Applied rewrites99.7%

    \[\leadsto \frac{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}{1 + \color{blue}{\frac{\mathsf{fma}\left(0.5, \cos \left(x + x\right), -0.5\right)}{\mathsf{fma}\left(-0.5, \cos \left(x + x\right), -0.5\right)}}} \]
  9. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{\color{blue}{\cos \left(x + x\right) \cdot \frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}}{1 + \frac{\mathsf{fma}\left(\frac{1}{2}, \cos \left(x + x\right), \frac{-1}{2}\right)}{\mathsf{fma}\left(\frac{-1}{2}, \cos \left(x + x\right), \frac{-1}{2}\right)}} \]
    2. lift-/.f64N/A

      \[\leadsto \frac{\cos \left(x + x\right) \cdot \color{blue}{\frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}}{1 + \frac{\mathsf{fma}\left(\frac{1}{2}, \cos \left(x + x\right), \frac{-1}{2}\right)}{\mathsf{fma}\left(\frac{-1}{2}, \cos \left(x + x\right), \frac{-1}{2}\right)}} \]
    3. mult-flip-revN/A

      \[\leadsto \frac{\color{blue}{\frac{\cos \left(x + x\right)}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}}{1 + \frac{\mathsf{fma}\left(\frac{1}{2}, \cos \left(x + x\right), \frac{-1}{2}\right)}{\mathsf{fma}\left(\frac{-1}{2}, \cos \left(x + x\right), \frac{-1}{2}\right)}} \]
    4. lower-/.f6499.6%

      \[\leadsto \frac{\color{blue}{\frac{\cos \left(x + x\right)}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}}{1 + \frac{\mathsf{fma}\left(0.5, \cos \left(x + x\right), -0.5\right)}{\mathsf{fma}\left(-0.5, \cos \left(x + x\right), -0.5\right)}} \]
    5. lift-fma.f64N/A

      \[\leadsto \frac{\frac{\cos \left(x + x\right)}{\color{blue}{\cos \left(x + x\right) \cdot \frac{1}{2} + \frac{1}{2}}}}{1 + \frac{\mathsf{fma}\left(\frac{1}{2}, \cos \left(x + x\right), \frac{-1}{2}\right)}{\mathsf{fma}\left(\frac{-1}{2}, \cos \left(x + x\right), \frac{-1}{2}\right)}} \]
    6. *-commutativeN/A

      \[\leadsto \frac{\frac{\cos \left(x + x\right)}{\color{blue}{\frac{1}{2} \cdot \cos \left(x + x\right)} + \frac{1}{2}}}{1 + \frac{\mathsf{fma}\left(\frac{1}{2}, \cos \left(x + x\right), \frac{-1}{2}\right)}{\mathsf{fma}\left(\frac{-1}{2}, \cos \left(x + x\right), \frac{-1}{2}\right)}} \]
    7. lift-fma.f6499.6%

      \[\leadsto \frac{\frac{\cos \left(x + x\right)}{\color{blue}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}}}{1 + \frac{\mathsf{fma}\left(0.5, \cos \left(x + x\right), -0.5\right)}{\mathsf{fma}\left(-0.5, \cos \left(x + x\right), -0.5\right)}} \]
  10. Applied rewrites99.6%

    \[\leadsto \frac{\color{blue}{\frac{\cos \left(x + x\right)}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}}}{1 + \frac{\mathsf{fma}\left(0.5, \cos \left(x + x\right), -0.5\right)}{\mathsf{fma}\left(-0.5, \cos \left(x + x\right), -0.5\right)}} \]
  11. Add Preprocessing

Alternative 3: 99.5% accurate, 1.0× speedup?

\[\frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \tan x \cdot \tan x} \]
(FPCore (x)
  :precision binary64
  (/ (fma (tan x) (- (tan x)) 1.0) (+ 1.0 (* (tan x) (tan x)))))
double code(double x) {
	return fma(tan(x), -tan(x), 1.0) / (1.0 + (tan(x) * tan(x)));
}
function code(x)
	return Float64(fma(tan(x), Float64(-tan(x)), 1.0) / Float64(1.0 + Float64(tan(x) * tan(x))))
end
code[x_] := N[(N[(N[Tan[x], $MachinePrecision] * (-N[Tan[x], $MachinePrecision]) + 1.0), $MachinePrecision] / N[(1.0 + N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\frac{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}{1 + \tan x \cdot \tan x}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \frac{\color{blue}{1 - \tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
    2. sub-flipN/A

      \[\leadsto \frac{\color{blue}{1 + \left(\mathsf{neg}\left(\tan x \cdot \tan x\right)\right)}}{1 + \tan x \cdot \tan x} \]
    3. +-commutativeN/A

      \[\leadsto \frac{\color{blue}{\left(\mathsf{neg}\left(\tan x \cdot \tan x\right)\right) + 1}}{1 + \tan x \cdot \tan x} \]
    4. lift-*.f64N/A

      \[\leadsto \frac{\left(\mathsf{neg}\left(\color{blue}{\tan x \cdot \tan x}\right)\right) + 1}{1 + \tan x \cdot \tan x} \]
    5. distribute-rgt-neg-inN/A

      \[\leadsto \frac{\color{blue}{\tan x \cdot \left(\mathsf{neg}\left(\tan x\right)\right)} + 1}{1 + \tan x \cdot \tan x} \]
    6. lower-fma.f64N/A

      \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\tan x, \mathsf{neg}\left(\tan x\right), 1\right)}}{1 + \tan x \cdot \tan x} \]
    7. lower-neg.f6499.5%

      \[\leadsto \frac{\mathsf{fma}\left(\tan x, \color{blue}{-\tan x}, 1\right)}{1 + \tan x \cdot \tan x} \]
  3. Applied rewrites99.5%

    \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\tan x, -\tan x, 1\right)}}{1 + \tan x \cdot \tan x} \]
  4. Add Preprocessing

Alternative 4: 99.5% accurate, 1.0× speedup?

\[\frac{1 - \tan x \cdot \tan x}{\mathsf{fma}\left(\tan x, \tan x, 1\right)} \]
(FPCore (x)
  :precision binary64
  (/ (- 1.0 (* (tan x) (tan x))) (fma (tan x) (tan x) 1.0)))
double code(double x) {
	return (1.0 - (tan(x) * tan(x))) / fma(tan(x), tan(x), 1.0);
}
function code(x)
	return Float64(Float64(1.0 - Float64(tan(x) * tan(x))) / fma(tan(x), tan(x), 1.0))
end
code[x_] := N[(N[(1.0 - N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]
\frac{1 - \tan x \cdot \tan x}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{1 + \tan x \cdot \tan x}} \]
    2. +-commutativeN/A

      \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{\tan x \cdot \tan x + 1}} \]
    3. lift-*.f64N/A

      \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{\tan x \cdot \tan x} + 1} \]
    4. lower-fma.f6499.5%

      \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
  3. Applied rewrites99.5%

    \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{\mathsf{fma}\left(\tan x, \tan x, 1\right)}} \]
  4. Add Preprocessing

Alternative 5: 99.5% accurate, 1.4× speedup?

\[\begin{array}{l} t_0 := {\tan x}^{2}\\ \frac{1 - t\_0}{1 + t\_0} \end{array} \]
(FPCore (x)
  :precision binary64
  (let* ((t_0 (pow (tan x) 2.0))) (/ (- 1.0 t_0) (+ 1.0 t_0))))
double code(double x) {
	double t_0 = pow(tan(x), 2.0);
	return (1.0 - t_0) / (1.0 + t_0);
}
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
    real(8) :: t_0
    t_0 = tan(x) ** 2.0d0
    code = (1.0d0 - t_0) / (1.0d0 + t_0)
end function
public static double code(double x) {
	double t_0 = Math.pow(Math.tan(x), 2.0);
	return (1.0 - t_0) / (1.0 + t_0);
}
def code(x):
	t_0 = math.pow(math.tan(x), 2.0)
	return (1.0 - t_0) / (1.0 + t_0)
function code(x)
	t_0 = tan(x) ^ 2.0
	return Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0))
end
function tmp = code(x)
	t_0 = tan(x) ^ 2.0;
	tmp = (1.0 - t_0) / (1.0 + t_0);
end
code[x_] := Block[{t$95$0 = N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]}, N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
t_0 := {\tan x}^{2}\\
\frac{1 - t\_0}{1 + t\_0}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
    2. pow2N/A

      \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
    3. lower-pow.f6499.5%

      \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
  3. Applied rewrites99.5%

    \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    2. pow2N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
    3. lower-pow.f6499.5%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
  5. Applied rewrites99.5%

    \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
  6. Add Preprocessing

Alternative 6: 98.8% accurate, 1.5× speedup?

\[\frac{1 - {\tan x}^{2}}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}} \]
(FPCore (x)
  :precision binary64
  (/ (- 1.0 (pow (tan x) 2.0)) (/ 1.0 (fma 0.5 (cos (+ x x)) 0.5))))
double code(double x) {
	return (1.0 - pow(tan(x), 2.0)) / (1.0 / fma(0.5, cos((x + x)), 0.5));
}
function code(x)
	return Float64(Float64(1.0 - (tan(x) ^ 2.0)) / Float64(1.0 / fma(0.5, cos(Float64(x + x)), 0.5)))
end
code[x_] := N[(N[(1.0 - N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] / N[(1.0 / N[(0.5 * N[Cos[N[(x + x), $MachinePrecision]], $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\frac{1 - {\tan x}^{2}}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
    2. pow2N/A

      \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
    3. lower-pow.f6499.5%

      \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
  3. Applied rewrites99.5%

    \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    2. pow2N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
    3. lower-pow.f6499.5%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
  5. Applied rewrites99.5%

    \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
  6. Taylor expanded in x around inf

    \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
  7. Step-by-step derivation
    1. lower-+.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
    2. lower-/.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}} \]
    3. lower-pow.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\color{blue}{\cos x}}^{2}}} \]
    4. lower-sin.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\cos \color{blue}{x}}^{2}}} \]
    5. lower-pow.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\cos x}^{\color{blue}{2}}}} \]
    6. lower-cos.f6499.3%

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}} \]
  8. Applied rewrites99.3%

    \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
  9. Applied rewrites98.8%

    \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}}} \]
  10. Add Preprocessing

Alternative 7: 79.0% accurate, 1.1× speedup?

\[\begin{array}{l} t_0 := \tan \left(\left|x\right|\right)\\ \mathbf{if}\;t\_0 \leq -0.01:\\ \;\;\;\;\left(t\_0 - -1\right) \cdot \frac{t\_0 - 1}{\frac{1}{-1}}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{expm1}\left(\log t\_0 \cdot 2\right) \cdot \frac{-1}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(\left|x\right| + \left|x\right|\right), 0.5\right)}}\\ \end{array} \]
(FPCore (x)
  :precision binary64
  (let* ((t_0 (tan (fabs x))))
  (if (<= t_0 -0.01)
    (* (- t_0 -1.0) (/ (- t_0 1.0) (/ 1.0 -1.0)))
    (*
     (expm1 (* (log t_0) 2.0))
     (/ -1.0 (/ 1.0 (fma 0.5 (cos (+ (fabs x) (fabs x))) 0.5)))))))
double code(double x) {
	double t_0 = tan(fabs(x));
	double tmp;
	if (t_0 <= -0.01) {
		tmp = (t_0 - -1.0) * ((t_0 - 1.0) / (1.0 / -1.0));
	} else {
		tmp = expm1((log(t_0) * 2.0)) * (-1.0 / (1.0 / fma(0.5, cos((fabs(x) + fabs(x))), 0.5)));
	}
	return tmp;
}
function code(x)
	t_0 = tan(abs(x))
	tmp = 0.0
	if (t_0 <= -0.01)
		tmp = Float64(Float64(t_0 - -1.0) * Float64(Float64(t_0 - 1.0) / Float64(1.0 / -1.0)));
	else
		tmp = Float64(expm1(Float64(log(t_0) * 2.0)) * Float64(-1.0 / Float64(1.0 / fma(0.5, cos(Float64(abs(x) + abs(x))), 0.5))));
	end
	return tmp
end
code[x_] := Block[{t$95$0 = N[Tan[N[Abs[x], $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$0, -0.01], N[(N[(t$95$0 - -1.0), $MachinePrecision] * N[(N[(t$95$0 - 1.0), $MachinePrecision] / N[(1.0 / -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(Exp[N[(N[Log[t$95$0], $MachinePrecision] * 2.0), $MachinePrecision]] - 1), $MachinePrecision] * N[(-1.0 / N[(1.0 / N[(0.5 * N[Cos[N[(N[Abs[x], $MachinePrecision] + N[Abs[x], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
t_0 := \tan \left(\left|x\right|\right)\\
\mathbf{if}\;t\_0 \leq -0.01:\\
\;\;\;\;\left(t\_0 - -1\right) \cdot \frac{t\_0 - 1}{\frac{1}{-1}}\\

\mathbf{else}:\\
\;\;\;\;\mathsf{expm1}\left(\log t\_0 \cdot 2\right) \cdot \frac{-1}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(\left|x\right| + \left|x\right|\right), 0.5\right)}}\\


\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (tan.f64 x) < -0.01

    1. Initial program 99.5%

      \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    2. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \color{blue}{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}} \]
      2. frac-2negN/A

        \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(\left(1 - \tan x \cdot \tan x\right)\right)}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
      3. lift--.f64N/A

        \[\leadsto \frac{\mathsf{neg}\left(\color{blue}{\left(1 - \tan x \cdot \tan x\right)}\right)}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
      4. sub-negate-revN/A

        \[\leadsto \frac{\color{blue}{\tan x \cdot \tan x - 1}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
      5. lift-*.f64N/A

        \[\leadsto \frac{\color{blue}{\tan x \cdot \tan x} - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
      6. difference-of-sqr-1N/A

        \[\leadsto \frac{\color{blue}{\left(\tan x + 1\right) \cdot \left(\tan x - 1\right)}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
      7. associate-/l*N/A

        \[\leadsto \color{blue}{\left(\tan x + 1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
      8. lower-*.f64N/A

        \[\leadsto \color{blue}{\left(\tan x + 1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
      9. add-flipN/A

        \[\leadsto \color{blue}{\left(\tan x - \left(\mathsf{neg}\left(1\right)\right)\right)} \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
      10. metadata-evalN/A

        \[\leadsto \left(\tan x - \color{blue}{-1}\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
      11. lower--.f64N/A

        \[\leadsto \color{blue}{\left(\tan x - -1\right)} \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
      12. lower-/.f64N/A

        \[\leadsto \left(\tan x - -1\right) \cdot \color{blue}{\frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
      13. lower--.f64N/A

        \[\leadsto \left(\tan x - -1\right) \cdot \frac{\color{blue}{\tan x - 1}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
      14. lift-+.f64N/A

        \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)}\right)} \]
      15. distribute-neg-inN/A

        \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{\left(\mathsf{neg}\left(1\right)\right) + \left(\mathsf{neg}\left(\tan x \cdot \tan x\right)\right)}} \]
      16. metadata-evalN/A

        \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1} + \left(\mathsf{neg}\left(\tan x \cdot \tan x\right)\right)} \]
      17. sub-flip-reverseN/A

        \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1 - \tan x \cdot \tan x}} \]
      18. lower--.f6499.4%

        \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1 - \tan x \cdot \tan x}} \]
    3. Applied rewrites99.4%

      \[\leadsto \color{blue}{\left(\tan x - -1\right) \cdot \frac{\tan x - 1}{-1 - {\tan x}^{2}}} \]
    4. Applied rewrites98.8%

      \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{\frac{1}{\mathsf{fma}\left(-0.5, \cos \left(x + x\right), -0.5\right)}}} \]
    5. Taylor expanded in x around 0

      \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\frac{1}{\color{blue}{-1}}} \]
    6. Step-by-step derivation
      1. Applied rewrites59.1%

        \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\frac{1}{\color{blue}{-1}}} \]

      if -0.01 < (tan.f64 x)

      1. Initial program 99.5%

        \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
      2. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
        2. pow2N/A

          \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
        3. lower-pow.f6499.5%

          \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
      3. Applied rewrites99.5%

        \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
      4. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
        2. pow2N/A

          \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
        3. lower-pow.f6499.5%

          \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
      5. Applied rewrites99.5%

        \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
      6. Taylor expanded in x around inf

        \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
      7. Step-by-step derivation
        1. lower-+.f64N/A

          \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
        2. lower-/.f64N/A

          \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}} \]
        3. lower-pow.f64N/A

          \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\color{blue}{\cos x}}^{2}}} \]
        4. lower-sin.f64N/A

          \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\cos \color{blue}{x}}^{2}}} \]
        5. lower-pow.f64N/A

          \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\cos x}^{\color{blue}{2}}}} \]
        6. lower-cos.f6499.3%

          \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}} \]
      8. Applied rewrites99.3%

        \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
      9. Applied rewrites48.9%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(\log \tan x \cdot 2\right) \cdot \frac{-1}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}}} \]
    7. Recombined 2 regimes into one program.
    8. Add Preprocessing

    Alternative 8: 79.0% accurate, 1.1× speedup?

    \[\begin{array}{l} t_0 := \tan \left(\left|x\right|\right)\\ \mathbf{if}\;t\_0 \leq -0.01:\\ \;\;\;\;\left(t\_0 - -1\right) \cdot \frac{t\_0 - 1}{\frac{1}{-1}}\\ \mathbf{else}:\\ \;\;\;\;\frac{-\mathsf{expm1}\left(\log t\_0 \cdot 2\right)}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(\left|x\right| + \left|x\right|\right), 0.5\right)}}\\ \end{array} \]
    (FPCore (x)
      :precision binary64
      (let* ((t_0 (tan (fabs x))))
      (if (<= t_0 -0.01)
        (* (- t_0 -1.0) (/ (- t_0 1.0) (/ 1.0 -1.0)))
        (/
         (- (expm1 (* (log t_0) 2.0)))
         (/ 1.0 (fma 0.5 (cos (+ (fabs x) (fabs x))) 0.5))))))
    double code(double x) {
    	double t_0 = tan(fabs(x));
    	double tmp;
    	if (t_0 <= -0.01) {
    		tmp = (t_0 - -1.0) * ((t_0 - 1.0) / (1.0 / -1.0));
    	} else {
    		tmp = -expm1((log(t_0) * 2.0)) / (1.0 / fma(0.5, cos((fabs(x) + fabs(x))), 0.5));
    	}
    	return tmp;
    }
    
    function code(x)
    	t_0 = tan(abs(x))
    	tmp = 0.0
    	if (t_0 <= -0.01)
    		tmp = Float64(Float64(t_0 - -1.0) * Float64(Float64(t_0 - 1.0) / Float64(1.0 / -1.0)));
    	else
    		tmp = Float64(Float64(-expm1(Float64(log(t_0) * 2.0))) / Float64(1.0 / fma(0.5, cos(Float64(abs(x) + abs(x))), 0.5)));
    	end
    	return tmp
    end
    
    code[x_] := Block[{t$95$0 = N[Tan[N[Abs[x], $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$0, -0.01], N[(N[(t$95$0 - -1.0), $MachinePrecision] * N[(N[(t$95$0 - 1.0), $MachinePrecision] / N[(1.0 / -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[((-N[(Exp[N[(N[Log[t$95$0], $MachinePrecision] * 2.0), $MachinePrecision]] - 1), $MachinePrecision]) / N[(1.0 / N[(0.5 * N[Cos[N[(N[Abs[x], $MachinePrecision] + N[Abs[x], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
    
    \begin{array}{l}
    t_0 := \tan \left(\left|x\right|\right)\\
    \mathbf{if}\;t\_0 \leq -0.01:\\
    \;\;\;\;\left(t\_0 - -1\right) \cdot \frac{t\_0 - 1}{\frac{1}{-1}}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{-\mathsf{expm1}\left(\log t\_0 \cdot 2\right)}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(\left|x\right| + \left|x\right|\right), 0.5\right)}}\\
    
    
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (tan.f64 x) < -0.01

      1. Initial program 99.5%

        \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
      2. Step-by-step derivation
        1. lift-/.f64N/A

          \[\leadsto \color{blue}{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}} \]
        2. frac-2negN/A

          \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(\left(1 - \tan x \cdot \tan x\right)\right)}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
        3. lift--.f64N/A

          \[\leadsto \frac{\mathsf{neg}\left(\color{blue}{\left(1 - \tan x \cdot \tan x\right)}\right)}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        4. sub-negate-revN/A

          \[\leadsto \frac{\color{blue}{\tan x \cdot \tan x - 1}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        5. lift-*.f64N/A

          \[\leadsto \frac{\color{blue}{\tan x \cdot \tan x} - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        6. difference-of-sqr-1N/A

          \[\leadsto \frac{\color{blue}{\left(\tan x + 1\right) \cdot \left(\tan x - 1\right)}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        7. associate-/l*N/A

          \[\leadsto \color{blue}{\left(\tan x + 1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
        8. lower-*.f64N/A

          \[\leadsto \color{blue}{\left(\tan x + 1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
        9. add-flipN/A

          \[\leadsto \color{blue}{\left(\tan x - \left(\mathsf{neg}\left(1\right)\right)\right)} \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        10. metadata-evalN/A

          \[\leadsto \left(\tan x - \color{blue}{-1}\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        11. lower--.f64N/A

          \[\leadsto \color{blue}{\left(\tan x - -1\right)} \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        12. lower-/.f64N/A

          \[\leadsto \left(\tan x - -1\right) \cdot \color{blue}{\frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
        13. lower--.f64N/A

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\color{blue}{\tan x - 1}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        14. lift-+.f64N/A

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)}\right)} \]
        15. distribute-neg-inN/A

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{\left(\mathsf{neg}\left(1\right)\right) + \left(\mathsf{neg}\left(\tan x \cdot \tan x\right)\right)}} \]
        16. metadata-evalN/A

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1} + \left(\mathsf{neg}\left(\tan x \cdot \tan x\right)\right)} \]
        17. sub-flip-reverseN/A

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1 - \tan x \cdot \tan x}} \]
        18. lower--.f6499.4%

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1 - \tan x \cdot \tan x}} \]
      3. Applied rewrites99.4%

        \[\leadsto \color{blue}{\left(\tan x - -1\right) \cdot \frac{\tan x - 1}{-1 - {\tan x}^{2}}} \]
      4. Applied rewrites98.8%

        \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{\frac{1}{\mathsf{fma}\left(-0.5, \cos \left(x + x\right), -0.5\right)}}} \]
      5. Taylor expanded in x around 0

        \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\frac{1}{\color{blue}{-1}}} \]
      6. Step-by-step derivation
        1. Applied rewrites59.1%

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\frac{1}{\color{blue}{-1}}} \]

        if -0.01 < (tan.f64 x)

        1. Initial program 99.5%

          \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
        2. Step-by-step derivation
          1. lift-*.f64N/A

            \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
          2. pow2N/A

            \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
          3. lower-pow.f6499.5%

            \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
        3. Applied rewrites99.5%

          \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
        4. Step-by-step derivation
          1. lift-*.f64N/A

            \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
          2. pow2N/A

            \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
          3. lower-pow.f6499.5%

            \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
        5. Applied rewrites99.5%

          \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{{\tan x}^{2}}} \]
        6. Taylor expanded in x around inf

          \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
        7. Step-by-step derivation
          1. lower-+.f64N/A

            \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
          2. lower-/.f64N/A

            \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}} \]
          3. lower-pow.f64N/A

            \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\color{blue}{\cos x}}^{2}}} \]
          4. lower-sin.f64N/A

            \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\cos \color{blue}{x}}^{2}}} \]
          5. lower-pow.f64N/A

            \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\cos x}^{\color{blue}{2}}}} \]
          6. lower-cos.f6499.3%

            \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}} \]
        8. Applied rewrites99.3%

          \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{1 + \frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
        9. Applied rewrites48.9%

          \[\leadsto \color{blue}{\frac{-\mathsf{expm1}\left(\log \tan x \cdot 2\right)}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}}} \]
      7. Recombined 2 regimes into one program.
      8. Add Preprocessing

      Alternative 9: 59.1% accurate, 1.8× speedup?

      \[\left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\frac{1}{-1}} \]
      (FPCore (x)
        :precision binary64
        (* (- (tan x) -1.0) (/ (- (tan x) 1.0) (/ 1.0 -1.0))))
      double code(double x) {
      	return (tan(x) - -1.0) * ((tan(x) - 1.0) / (1.0 / -1.0));
      }
      
      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 = (tan(x) - (-1.0d0)) * ((tan(x) - 1.0d0) / (1.0d0 / (-1.0d0)))
      end function
      
      public static double code(double x) {
      	return (Math.tan(x) - -1.0) * ((Math.tan(x) - 1.0) / (1.0 / -1.0));
      }
      
      def code(x):
      	return (math.tan(x) - -1.0) * ((math.tan(x) - 1.0) / (1.0 / -1.0))
      
      function code(x)
      	return Float64(Float64(tan(x) - -1.0) * Float64(Float64(tan(x) - 1.0) / Float64(1.0 / -1.0)))
      end
      
      function tmp = code(x)
      	tmp = (tan(x) - -1.0) * ((tan(x) - 1.0) / (1.0 / -1.0));
      end
      
      code[x_] := N[(N[(N[Tan[x], $MachinePrecision] - -1.0), $MachinePrecision] * N[(N[(N[Tan[x], $MachinePrecision] - 1.0), $MachinePrecision] / N[(1.0 / -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\frac{1}{-1}}
      
      Derivation
      1. Initial program 99.5%

        \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
      2. Step-by-step derivation
        1. lift-/.f64N/A

          \[\leadsto \color{blue}{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}} \]
        2. frac-2negN/A

          \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(\left(1 - \tan x \cdot \tan x\right)\right)}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
        3. lift--.f64N/A

          \[\leadsto \frac{\mathsf{neg}\left(\color{blue}{\left(1 - \tan x \cdot \tan x\right)}\right)}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        4. sub-negate-revN/A

          \[\leadsto \frac{\color{blue}{\tan x \cdot \tan x - 1}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        5. lift-*.f64N/A

          \[\leadsto \frac{\color{blue}{\tan x \cdot \tan x} - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        6. difference-of-sqr-1N/A

          \[\leadsto \frac{\color{blue}{\left(\tan x + 1\right) \cdot \left(\tan x - 1\right)}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        7. associate-/l*N/A

          \[\leadsto \color{blue}{\left(\tan x + 1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
        8. lower-*.f64N/A

          \[\leadsto \color{blue}{\left(\tan x + 1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
        9. add-flipN/A

          \[\leadsto \color{blue}{\left(\tan x - \left(\mathsf{neg}\left(1\right)\right)\right)} \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        10. metadata-evalN/A

          \[\leadsto \left(\tan x - \color{blue}{-1}\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        11. lower--.f64N/A

          \[\leadsto \color{blue}{\left(\tan x - -1\right)} \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        12. lower-/.f64N/A

          \[\leadsto \left(\tan x - -1\right) \cdot \color{blue}{\frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
        13. lower--.f64N/A

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\color{blue}{\tan x - 1}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
        14. lift-+.f64N/A

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)}\right)} \]
        15. distribute-neg-inN/A

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{\left(\mathsf{neg}\left(1\right)\right) + \left(\mathsf{neg}\left(\tan x \cdot \tan x\right)\right)}} \]
        16. metadata-evalN/A

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1} + \left(\mathsf{neg}\left(\tan x \cdot \tan x\right)\right)} \]
        17. sub-flip-reverseN/A

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1 - \tan x \cdot \tan x}} \]
        18. lower--.f6499.4%

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1 - \tan x \cdot \tan x}} \]
      3. Applied rewrites99.4%

        \[\leadsto \color{blue}{\left(\tan x - -1\right) \cdot \frac{\tan x - 1}{-1 - {\tan x}^{2}}} \]
      4. Applied rewrites98.8%

        \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{\frac{1}{\mathsf{fma}\left(-0.5, \cos \left(x + x\right), -0.5\right)}}} \]
      5. Taylor expanded in x around 0

        \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\frac{1}{\color{blue}{-1}}} \]
      6. Step-by-step derivation
        1. Applied rewrites59.1%

          \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\frac{1}{\color{blue}{-1}}} \]
        2. Add Preprocessing

        Alternative 10: 57.4% accurate, 0.8× speedup?

        \[\begin{array}{l} t_0 := \tan x \cdot \tan x\\ \mathbf{if}\;\frac{1 - t\_0}{1 + t\_0} \leq -0.05:\\ \;\;\;\;\frac{1 - {x}^{2}}{1 + {x}^{2}}\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right) \cdot 1\\ \end{array} \]
        (FPCore (x)
          :precision binary64
          (let* ((t_0 (* (tan x) (tan x))))
          (if (<= (/ (- 1.0 t_0) (+ 1.0 t_0)) -0.05)
            (/ (- 1.0 (pow x 2.0)) (+ 1.0 (pow x 2.0)))
            (* (fma 0.5 (cos (+ x x)) 0.5) 1.0))))
        double code(double x) {
        	double t_0 = tan(x) * tan(x);
        	double tmp;
        	if (((1.0 - t_0) / (1.0 + t_0)) <= -0.05) {
        		tmp = (1.0 - pow(x, 2.0)) / (1.0 + pow(x, 2.0));
        	} else {
        		tmp = fma(0.5, cos((x + x)), 0.5) * 1.0;
        	}
        	return tmp;
        }
        
        function code(x)
        	t_0 = Float64(tan(x) * tan(x))
        	tmp = 0.0
        	if (Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0)) <= -0.05)
        		tmp = Float64(Float64(1.0 - (x ^ 2.0)) / Float64(1.0 + (x ^ 2.0)));
        	else
        		tmp = Float64(fma(0.5, cos(Float64(x + x)), 0.5) * 1.0);
        	end
        	return tmp
        end
        
        code[x_] := Block[{t$95$0 = N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision], -0.05], N[(N[(1.0 - N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(0.5 * N[Cos[N[(x + x), $MachinePrecision]], $MachinePrecision] + 0.5), $MachinePrecision] * 1.0), $MachinePrecision]]]
        
        \begin{array}{l}
        t_0 := \tan x \cdot \tan x\\
        \mathbf{if}\;\frac{1 - t\_0}{1 + t\_0} \leq -0.05:\\
        \;\;\;\;\frac{1 - {x}^{2}}{1 + {x}^{2}}\\
        
        \mathbf{else}:\\
        \;\;\;\;\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right) \cdot 1\\
        
        
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (/.f64 (-.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))) (+.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x)))) < -0.050000000000000003

          1. Initial program 99.5%

            \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
          2. Taylor expanded in x around 0

            \[\leadsto \frac{1 - \color{blue}{{x}^{2}}}{1 + \tan x \cdot \tan x} \]
          3. Step-by-step derivation
            1. lower-pow.f6450.6%

              \[\leadsto \frac{1 - {x}^{\color{blue}{2}}}{1 + \tan x \cdot \tan x} \]
          4. Applied rewrites50.6%

            \[\leadsto \frac{1 - \color{blue}{{x}^{2}}}{1 + \tan x \cdot \tan x} \]
          5. Taylor expanded in x around 0

            \[\leadsto \frac{1 - {x}^{2}}{1 + \color{blue}{{x}^{2}}} \]
          6. Step-by-step derivation
            1. lower-pow.f6452.2%

              \[\leadsto \frac{1 - {x}^{2}}{1 + {x}^{\color{blue}{2}}} \]
          7. Applied rewrites52.2%

            \[\leadsto \frac{1 - {x}^{2}}{1 + \color{blue}{{x}^{2}}} \]

          if -0.050000000000000003 < (/.f64 (-.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))) (+.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))))

          1. Initial program 99.5%

            \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
          2. Taylor expanded in x around 0

            \[\leadsto \frac{\color{blue}{1}}{1 + \tan x \cdot \tan x} \]
          3. Step-by-step derivation
            1. Applied rewrites55.2%

              \[\leadsto \frac{\color{blue}{1}}{1 + \tan x \cdot \tan x} \]
            2. Applied rewrites55.2%

              \[\leadsto \color{blue}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right) \cdot 1} \]
          4. Recombined 2 regimes into one program.
          5. Add Preprocessing

          Alternative 11: 57.4% accurate, 0.8× speedup?

          \[\begin{array}{l} t_0 := \tan x \cdot \tan x\\ \mathbf{if}\;\frac{1 - t\_0}{1 + t\_0} \leq -0.05:\\ \;\;\;\;\frac{1 - {x}^{2}}{1 + {x}^{2}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}}\\ \end{array} \]
          (FPCore (x)
            :precision binary64
            (let* ((t_0 (* (tan x) (tan x))))
            (if (<= (/ (- 1.0 t_0) (+ 1.0 t_0)) -0.05)
              (/ (- 1.0 (pow x 2.0)) (+ 1.0 (pow x 2.0)))
              (/ 1.0 (/ 1.0 (fma 0.5 (cos (+ x x)) 0.5))))))
          double code(double x) {
          	double t_0 = tan(x) * tan(x);
          	double tmp;
          	if (((1.0 - t_0) / (1.0 + t_0)) <= -0.05) {
          		tmp = (1.0 - pow(x, 2.0)) / (1.0 + pow(x, 2.0));
          	} else {
          		tmp = 1.0 / (1.0 / fma(0.5, cos((x + x)), 0.5));
          	}
          	return tmp;
          }
          
          function code(x)
          	t_0 = Float64(tan(x) * tan(x))
          	tmp = 0.0
          	if (Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0)) <= -0.05)
          		tmp = Float64(Float64(1.0 - (x ^ 2.0)) / Float64(1.0 + (x ^ 2.0)));
          	else
          		tmp = Float64(1.0 / Float64(1.0 / fma(0.5, cos(Float64(x + x)), 0.5)));
          	end
          	return tmp
          end
          
          code[x_] := Block[{t$95$0 = N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision], -0.05], N[(N[(1.0 - N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(1.0 / N[(0.5 * N[Cos[N[(x + x), $MachinePrecision]], $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
          
          \begin{array}{l}
          t_0 := \tan x \cdot \tan x\\
          \mathbf{if}\;\frac{1 - t\_0}{1 + t\_0} \leq -0.05:\\
          \;\;\;\;\frac{1 - {x}^{2}}{1 + {x}^{2}}\\
          
          \mathbf{else}:\\
          \;\;\;\;\frac{1}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}}\\
          
          
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if (/.f64 (-.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))) (+.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x)))) < -0.050000000000000003

            1. Initial program 99.5%

              \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
            2. Taylor expanded in x around 0

              \[\leadsto \frac{1 - \color{blue}{{x}^{2}}}{1 + \tan x \cdot \tan x} \]
            3. Step-by-step derivation
              1. lower-pow.f6450.6%

                \[\leadsto \frac{1 - {x}^{\color{blue}{2}}}{1 + \tan x \cdot \tan x} \]
            4. Applied rewrites50.6%

              \[\leadsto \frac{1 - \color{blue}{{x}^{2}}}{1 + \tan x \cdot \tan x} \]
            5. Taylor expanded in x around 0

              \[\leadsto \frac{1 - {x}^{2}}{1 + \color{blue}{{x}^{2}}} \]
            6. Step-by-step derivation
              1. lower-pow.f6452.2%

                \[\leadsto \frac{1 - {x}^{2}}{1 + {x}^{\color{blue}{2}}} \]
            7. Applied rewrites52.2%

              \[\leadsto \frac{1 - {x}^{2}}{1 + \color{blue}{{x}^{2}}} \]

            if -0.050000000000000003 < (/.f64 (-.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))) (+.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))))

            1. Initial program 99.5%

              \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
            2. Taylor expanded in x around 0

              \[\leadsto \frac{\color{blue}{1}}{1 + \tan x \cdot \tan x} \]
            3. Step-by-step derivation
              1. Applied rewrites55.2%

                \[\leadsto \frac{\color{blue}{1}}{1 + \tan x \cdot \tan x} \]
              2. Step-by-step derivation
                1. lift-+.f64N/A

                  \[\leadsto \frac{1}{\color{blue}{1 + \tan x \cdot \tan x}} \]
                2. lift-*.f64N/A

                  \[\leadsto \frac{1}{1 + \color{blue}{\tan x \cdot \tan x}} \]
                3. lift-tan.f64N/A

                  \[\leadsto \frac{1}{1 + \color{blue}{\tan x} \cdot \tan x} \]
                4. lift-tan.f64N/A

                  \[\leadsto \frac{1}{1 + \tan x \cdot \color{blue}{\tan x}} \]
                5. tan-quotN/A

                  \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x} \]
                6. lift-sin.f64N/A

                  \[\leadsto \frac{1}{1 + \frac{\color{blue}{\sin x}}{\cos x} \cdot \tan x} \]
                7. lift-cos.f64N/A

                  \[\leadsto \frac{1}{1 + \frac{\sin x}{\color{blue}{\cos x}} \cdot \tan x} \]
                8. tan-quotN/A

                  \[\leadsto \frac{1}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
                9. lift-sin.f64N/A

                  \[\leadsto \frac{1}{1 + \frac{\sin x}{\cos x} \cdot \frac{\color{blue}{\sin x}}{\cos x}} \]
                10. lift-cos.f64N/A

                  \[\leadsto \frac{1}{1 + \frac{\sin x}{\cos x} \cdot \frac{\sin x}{\color{blue}{\cos x}}} \]
                11. frac-timesN/A

                  \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}} \]
                12. unpow2N/A

                  \[\leadsto \frac{1}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}} \]
                13. lift-pow.f64N/A

                  \[\leadsto \frac{1}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}} \]
                14. lift-cos.f64N/A

                  \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\color{blue}{\cos x} \cdot \cos x}} \]
                15. lift-cos.f64N/A

                  \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\cos x \cdot \color{blue}{\cos x}}} \]
                16. sqr-cos-a-revN/A

                  \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
                17. count-2N/A

                  \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \color{blue}{\left(x + x\right)}}} \]
                18. lift-+.f64N/A

                  \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \color{blue}{\left(x + x\right)}}} \]
                19. lift-cos.f64N/A

                  \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(x + x\right)}}} \]
                20. lift-*.f64N/A

                  \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(x + x\right)}}} \]
                21. lift-+.f64N/A

                  \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}} \]
              3. Applied rewrites55.2%

                \[\leadsto \color{blue}{\frac{1}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}}} \]
            4. Recombined 2 regimes into one program.
            5. Add Preprocessing

            Alternative 12: 57.0% accurate, 0.8× speedup?

            \[\begin{array}{l} t_0 := \tan x \cdot \tan x\\ \mathbf{if}\;\frac{1 - t\_0}{1 + t\_0} \leq -0.05:\\ \;\;\;\;\frac{1 - {x}^{2}}{1 + {x}^{2}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\frac{1}{\mathsf{fma}\left(0.5, 1, 0.5\right)}}\\ \end{array} \]
            (FPCore (x)
              :precision binary64
              (let* ((t_0 (* (tan x) (tan x))))
              (if (<= (/ (- 1.0 t_0) (+ 1.0 t_0)) -0.05)
                (/ (- 1.0 (pow x 2.0)) (+ 1.0 (pow x 2.0)))
                (/ 1.0 (/ 1.0 (fma 0.5 1.0 0.5))))))
            double code(double x) {
            	double t_0 = tan(x) * tan(x);
            	double tmp;
            	if (((1.0 - t_0) / (1.0 + t_0)) <= -0.05) {
            		tmp = (1.0 - pow(x, 2.0)) / (1.0 + pow(x, 2.0));
            	} else {
            		tmp = 1.0 / (1.0 / fma(0.5, 1.0, 0.5));
            	}
            	return tmp;
            }
            
            function code(x)
            	t_0 = Float64(tan(x) * tan(x))
            	tmp = 0.0
            	if (Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0)) <= -0.05)
            		tmp = Float64(Float64(1.0 - (x ^ 2.0)) / Float64(1.0 + (x ^ 2.0)));
            	else
            		tmp = Float64(1.0 / Float64(1.0 / fma(0.5, 1.0, 0.5)));
            	end
            	return tmp
            end
            
            code[x_] := Block[{t$95$0 = N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision], -0.05], N[(N[(1.0 - N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(1.0 / N[(1.0 / N[(0.5 * 1.0 + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
            
            \begin{array}{l}
            t_0 := \tan x \cdot \tan x\\
            \mathbf{if}\;\frac{1 - t\_0}{1 + t\_0} \leq -0.05:\\
            \;\;\;\;\frac{1 - {x}^{2}}{1 + {x}^{2}}\\
            
            \mathbf{else}:\\
            \;\;\;\;\frac{1}{\frac{1}{\mathsf{fma}\left(0.5, 1, 0.5\right)}}\\
            
            
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if (/.f64 (-.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))) (+.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x)))) < -0.050000000000000003

              1. Initial program 99.5%

                \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
              2. Taylor expanded in x around 0

                \[\leadsto \frac{1 - \color{blue}{{x}^{2}}}{1 + \tan x \cdot \tan x} \]
              3. Step-by-step derivation
                1. lower-pow.f6450.6%

                  \[\leadsto \frac{1 - {x}^{\color{blue}{2}}}{1 + \tan x \cdot \tan x} \]
              4. Applied rewrites50.6%

                \[\leadsto \frac{1 - \color{blue}{{x}^{2}}}{1 + \tan x \cdot \tan x} \]
              5. Taylor expanded in x around 0

                \[\leadsto \frac{1 - {x}^{2}}{1 + \color{blue}{{x}^{2}}} \]
              6. Step-by-step derivation
                1. lower-pow.f6452.2%

                  \[\leadsto \frac{1 - {x}^{2}}{1 + {x}^{\color{blue}{2}}} \]
              7. Applied rewrites52.2%

                \[\leadsto \frac{1 - {x}^{2}}{1 + \color{blue}{{x}^{2}}} \]

              if -0.050000000000000003 < (/.f64 (-.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))) (+.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))))

              1. Initial program 99.5%

                \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
              2. Taylor expanded in x around 0

                \[\leadsto \frac{\color{blue}{1}}{1 + \tan x \cdot \tan x} \]
              3. Step-by-step derivation
                1. Applied rewrites55.2%

                  \[\leadsto \frac{\color{blue}{1}}{1 + \tan x \cdot \tan x} \]
                2. Step-by-step derivation
                  1. lift-+.f64N/A

                    \[\leadsto \frac{1}{\color{blue}{1 + \tan x \cdot \tan x}} \]
                  2. lift-*.f64N/A

                    \[\leadsto \frac{1}{1 + \color{blue}{\tan x \cdot \tan x}} \]
                  3. lift-tan.f64N/A

                    \[\leadsto \frac{1}{1 + \color{blue}{\tan x} \cdot \tan x} \]
                  4. lift-tan.f64N/A

                    \[\leadsto \frac{1}{1 + \tan x \cdot \color{blue}{\tan x}} \]
                  5. tan-quotN/A

                    \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x} \]
                  6. lift-sin.f64N/A

                    \[\leadsto \frac{1}{1 + \frac{\color{blue}{\sin x}}{\cos x} \cdot \tan x} \]
                  7. lift-cos.f64N/A

                    \[\leadsto \frac{1}{1 + \frac{\sin x}{\color{blue}{\cos x}} \cdot \tan x} \]
                  8. tan-quotN/A

                    \[\leadsto \frac{1}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
                  9. lift-sin.f64N/A

                    \[\leadsto \frac{1}{1 + \frac{\sin x}{\cos x} \cdot \frac{\color{blue}{\sin x}}{\cos x}} \]
                  10. lift-cos.f64N/A

                    \[\leadsto \frac{1}{1 + \frac{\sin x}{\cos x} \cdot \frac{\sin x}{\color{blue}{\cos x}}} \]
                  11. frac-timesN/A

                    \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}} \]
                  12. unpow2N/A

                    \[\leadsto \frac{1}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}} \]
                  13. lift-pow.f64N/A

                    \[\leadsto \frac{1}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}} \]
                  14. lift-cos.f64N/A

                    \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\color{blue}{\cos x} \cdot \cos x}} \]
                  15. lift-cos.f64N/A

                    \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\cos x \cdot \color{blue}{\cos x}}} \]
                  16. sqr-cos-a-revN/A

                    \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
                  17. count-2N/A

                    \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \color{blue}{\left(x + x\right)}}} \]
                  18. lift-+.f64N/A

                    \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \color{blue}{\left(x + x\right)}}} \]
                  19. lift-cos.f64N/A

                    \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(x + x\right)}}} \]
                  20. lift-*.f64N/A

                    \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(x + x\right)}}} \]
                  21. lift-+.f64N/A

                    \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}} \]
                3. Applied rewrites55.2%

                  \[\leadsto \color{blue}{\frac{1}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}}} \]
                4. Taylor expanded in x around 0

                  \[\leadsto \frac{1}{\frac{1}{\mathsf{fma}\left(0.5, \color{blue}{1}, 0.5\right)}} \]
                5. Step-by-step derivation
                  1. Applied rewrites54.8%

                    \[\leadsto \frac{1}{\frac{1}{\mathsf{fma}\left(0.5, \color{blue}{1}, 0.5\right)}} \]
                6. Recombined 2 regimes into one program.
                7. Add Preprocessing

                Alternative 13: 56.1% accurate, 1.8× speedup?

                \[\left(\tan \left(\left|x\right|\right) - -1\right) \cdot \left(\mathsf{fma}\left(-0.5, \cos \left(\left|x\right| + \left|x\right|\right), -0.5\right) \cdot -1\right) \]
                (FPCore (x)
                  :precision binary64
                  (*
                 (- (tan (fabs x)) -1.0)
                 (* (fma -0.5 (cos (+ (fabs x) (fabs x))) -0.5) -1.0)))
                double code(double x) {
                	return (tan(fabs(x)) - -1.0) * (fma(-0.5, cos((fabs(x) + fabs(x))), -0.5) * -1.0);
                }
                
                function code(x)
                	return Float64(Float64(tan(abs(x)) - -1.0) * Float64(fma(-0.5, cos(Float64(abs(x) + abs(x))), -0.5) * -1.0))
                end
                
                code[x_] := N[(N[(N[Tan[N[Abs[x], $MachinePrecision]], $MachinePrecision] - -1.0), $MachinePrecision] * N[(N[(-0.5 * N[Cos[N[(N[Abs[x], $MachinePrecision] + N[Abs[x], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + -0.5), $MachinePrecision] * -1.0), $MachinePrecision]), $MachinePrecision]
                
                \left(\tan \left(\left|x\right|\right) - -1\right) \cdot \left(\mathsf{fma}\left(-0.5, \cos \left(\left|x\right| + \left|x\right|\right), -0.5\right) \cdot -1\right)
                
                Derivation
                1. Initial program 99.5%

                  \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
                2. Step-by-step derivation
                  1. lift-/.f64N/A

                    \[\leadsto \color{blue}{\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}} \]
                  2. frac-2negN/A

                    \[\leadsto \color{blue}{\frac{\mathsf{neg}\left(\left(1 - \tan x \cdot \tan x\right)\right)}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
                  3. lift--.f64N/A

                    \[\leadsto \frac{\mathsf{neg}\left(\color{blue}{\left(1 - \tan x \cdot \tan x\right)}\right)}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
                  4. sub-negate-revN/A

                    \[\leadsto \frac{\color{blue}{\tan x \cdot \tan x - 1}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
                  5. lift-*.f64N/A

                    \[\leadsto \frac{\color{blue}{\tan x \cdot \tan x} - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
                  6. difference-of-sqr-1N/A

                    \[\leadsto \frac{\color{blue}{\left(\tan x + 1\right) \cdot \left(\tan x - 1\right)}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
                  7. associate-/l*N/A

                    \[\leadsto \color{blue}{\left(\tan x + 1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
                  8. lower-*.f64N/A

                    \[\leadsto \color{blue}{\left(\tan x + 1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
                  9. add-flipN/A

                    \[\leadsto \color{blue}{\left(\tan x - \left(\mathsf{neg}\left(1\right)\right)\right)} \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
                  10. metadata-evalN/A

                    \[\leadsto \left(\tan x - \color{blue}{-1}\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
                  11. lower--.f64N/A

                    \[\leadsto \color{blue}{\left(\tan x - -1\right)} \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
                  12. lower-/.f64N/A

                    \[\leadsto \left(\tan x - -1\right) \cdot \color{blue}{\frac{\tan x - 1}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)}} \]
                  13. lower--.f64N/A

                    \[\leadsto \left(\tan x - -1\right) \cdot \frac{\color{blue}{\tan x - 1}}{\mathsf{neg}\left(\left(1 + \tan x \cdot \tan x\right)\right)} \]
                  14. lift-+.f64N/A

                    \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\mathsf{neg}\left(\color{blue}{\left(1 + \tan x \cdot \tan x\right)}\right)} \]
                  15. distribute-neg-inN/A

                    \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{\left(\mathsf{neg}\left(1\right)\right) + \left(\mathsf{neg}\left(\tan x \cdot \tan x\right)\right)}} \]
                  16. metadata-evalN/A

                    \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1} + \left(\mathsf{neg}\left(\tan x \cdot \tan x\right)\right)} \]
                  17. sub-flip-reverseN/A

                    \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1 - \tan x \cdot \tan x}} \]
                  18. lower--.f6499.4%

                    \[\leadsto \left(\tan x - -1\right) \cdot \frac{\tan x - 1}{\color{blue}{-1 - \tan x \cdot \tan x}} \]
                3. Applied rewrites99.4%

                  \[\leadsto \color{blue}{\left(\tan x - -1\right) \cdot \frac{\tan x - 1}{-1 - {\tan x}^{2}}} \]
                4. Taylor expanded in x around 0

                  \[\leadsto \left(\tan x - -1\right) \cdot \frac{\color{blue}{-1}}{-1 - {\tan x}^{2}} \]
                5. Step-by-step derivation
                  1. Applied rewrites56.1%

                    \[\leadsto \left(\tan x - -1\right) \cdot \frac{\color{blue}{-1}}{-1 - {\tan x}^{2}} \]
                  2. Applied rewrites56.1%

                    \[\leadsto \left(\tan x - -1\right) \cdot \color{blue}{\left(\mathsf{fma}\left(-0.5, \cos \left(x + x\right), -0.5\right) \cdot -1\right)} \]
                  3. Add Preprocessing

                  Alternative 14: 54.8% accurate, 12.1× speedup?

                  \[\frac{1}{\frac{1}{\mathsf{fma}\left(0.5, 1, 0.5\right)}} \]
                  (FPCore (x)
                    :precision binary64
                    (/ 1.0 (/ 1.0 (fma 0.5 1.0 0.5))))
                  double code(double x) {
                  	return 1.0 / (1.0 / fma(0.5, 1.0, 0.5));
                  }
                  
                  function code(x)
                  	return Float64(1.0 / Float64(1.0 / fma(0.5, 1.0, 0.5)))
                  end
                  
                  code[x_] := N[(1.0 / N[(1.0 / N[(0.5 * 1.0 + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                  
                  \frac{1}{\frac{1}{\mathsf{fma}\left(0.5, 1, 0.5\right)}}
                  
                  Derivation
                  1. Initial program 99.5%

                    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
                  2. Taylor expanded in x around 0

                    \[\leadsto \frac{\color{blue}{1}}{1 + \tan x \cdot \tan x} \]
                  3. Step-by-step derivation
                    1. Applied rewrites55.2%

                      \[\leadsto \frac{\color{blue}{1}}{1 + \tan x \cdot \tan x} \]
                    2. Step-by-step derivation
                      1. lift-+.f64N/A

                        \[\leadsto \frac{1}{\color{blue}{1 + \tan x \cdot \tan x}} \]
                      2. lift-*.f64N/A

                        \[\leadsto \frac{1}{1 + \color{blue}{\tan x \cdot \tan x}} \]
                      3. lift-tan.f64N/A

                        \[\leadsto \frac{1}{1 + \color{blue}{\tan x} \cdot \tan x} \]
                      4. lift-tan.f64N/A

                        \[\leadsto \frac{1}{1 + \tan x \cdot \color{blue}{\tan x}} \]
                      5. tan-quotN/A

                        \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x} \]
                      6. lift-sin.f64N/A

                        \[\leadsto \frac{1}{1 + \frac{\color{blue}{\sin x}}{\cos x} \cdot \tan x} \]
                      7. lift-cos.f64N/A

                        \[\leadsto \frac{1}{1 + \frac{\sin x}{\color{blue}{\cos x}} \cdot \tan x} \]
                      8. tan-quotN/A

                        \[\leadsto \frac{1}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
                      9. lift-sin.f64N/A

                        \[\leadsto \frac{1}{1 + \frac{\sin x}{\cos x} \cdot \frac{\color{blue}{\sin x}}{\cos x}} \]
                      10. lift-cos.f64N/A

                        \[\leadsto \frac{1}{1 + \frac{\sin x}{\cos x} \cdot \frac{\sin x}{\color{blue}{\cos x}}} \]
                      11. frac-timesN/A

                        \[\leadsto \frac{1}{1 + \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}} \]
                      12. unpow2N/A

                        \[\leadsto \frac{1}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}} \]
                      13. lift-pow.f64N/A

                        \[\leadsto \frac{1}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}} \]
                      14. lift-cos.f64N/A

                        \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\color{blue}{\cos x} \cdot \cos x}} \]
                      15. lift-cos.f64N/A

                        \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\cos x \cdot \color{blue}{\cos x}}} \]
                      16. sqr-cos-a-revN/A

                        \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
                      17. count-2N/A

                        \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \color{blue}{\left(x + x\right)}}} \]
                      18. lift-+.f64N/A

                        \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \frac{1}{2} \cdot \cos \color{blue}{\left(x + x\right)}}} \]
                      19. lift-cos.f64N/A

                        \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(x + x\right)}}} \]
                      20. lift-*.f64N/A

                        \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(x + x\right)}}} \]
                      21. lift-+.f64N/A

                        \[\leadsto \frac{1}{1 + \frac{{\sin x}^{2}}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(x + x\right)}}} \]
                    3. Applied rewrites55.2%

                      \[\leadsto \color{blue}{\frac{1}{\frac{1}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)}}} \]
                    4. Taylor expanded in x around 0

                      \[\leadsto \frac{1}{\frac{1}{\mathsf{fma}\left(0.5, \color{blue}{1}, 0.5\right)}} \]
                    5. Step-by-step derivation
                      1. Applied rewrites54.8%

                        \[\leadsto \frac{1}{\frac{1}{\mathsf{fma}\left(0.5, \color{blue}{1}, 0.5\right)}} \]
                      2. Add Preprocessing

                      Alternative 15: 50.6% accurate, 18.3× speedup?

                      \[\mathsf{fma}\left(x \cdot x, -2, 1\right) \]
                      (FPCore (x)
                        :precision binary64
                        (fma (* x x) -2.0 1.0))
                      double code(double x) {
                      	return fma((x * x), -2.0, 1.0);
                      }
                      
                      function code(x)
                      	return fma(Float64(x * x), -2.0, 1.0)
                      end
                      
                      code[x_] := N[(N[(x * x), $MachinePrecision] * -2.0 + 1.0), $MachinePrecision]
                      
                      \mathsf{fma}\left(x \cdot x, -2, 1\right)
                      
                      Derivation
                      1. Initial program 99.5%

                        \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
                      2. Taylor expanded in x around 0

                        \[\leadsto \color{blue}{1 + -2 \cdot {x}^{2}} \]
                      3. Step-by-step derivation
                        1. lower-+.f64N/A

                          \[\leadsto 1 + \color{blue}{-2 \cdot {x}^{2}} \]
                        2. lower-*.f64N/A

                          \[\leadsto 1 + -2 \cdot \color{blue}{{x}^{2}} \]
                        3. lower-pow.f6450.6%

                          \[\leadsto 1 + -2 \cdot {x}^{\color{blue}{2}} \]
                      4. Applied rewrites50.6%

                        \[\leadsto \color{blue}{1 + -2 \cdot {x}^{2}} \]
                      5. Step-by-step derivation
                        1. lift-+.f64N/A

                          \[\leadsto 1 + \color{blue}{-2 \cdot {x}^{2}} \]
                        2. +-commutativeN/A

                          \[\leadsto -2 \cdot {x}^{2} + \color{blue}{1} \]
                        3. lift-*.f64N/A

                          \[\leadsto -2 \cdot {x}^{2} + 1 \]
                        4. *-commutativeN/A

                          \[\leadsto {x}^{2} \cdot -2 + 1 \]
                        5. lower-fma.f6450.6%

                          \[\leadsto \mathsf{fma}\left({x}^{2}, \color{blue}{-2}, 1\right) \]
                        6. lift-pow.f64N/A

                          \[\leadsto \mathsf{fma}\left({x}^{2}, -2, 1\right) \]
                        7. unpow2N/A

                          \[\leadsto \mathsf{fma}\left(x \cdot x, -2, 1\right) \]
                        8. lower-*.f6450.6%

                          \[\leadsto \mathsf{fma}\left(x \cdot x, -2, 1\right) \]
                      6. Applied rewrites50.6%

                        \[\leadsto \mathsf{fma}\left(x \cdot x, \color{blue}{-2}, 1\right) \]
                      7. Add Preprocessing

                      Reproduce

                      ?
                      herbie shell --seed 2025212 
                      (FPCore (x)
                        :name "Trigonometry B"
                        :precision binary64
                        (/ (- 1.0 (* (tan x) (tan x))) (+ 1.0 (* (tan x) (tan x)))))