Trigonometry B

Percentage Accurate: 99.5% → 99.7%
Time: 3.7s
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. 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. Step-by-step derivation
              1. lift-/.f64N/A

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

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

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

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

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

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

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

                \[\leadsto \color{blue}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right) \cdot 1} \]
              9. lower-*.f6455.2%

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

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

                \[\leadsto \left(\color{blue}{\frac{1}{2} \cdot \cos \left(x + x\right)} + \frac{1}{2}\right) \cdot 1 \]
              12. lift-fma.f6455.2%

                \[\leadsto \color{blue}{\mathsf{fma}\left(0.5, \cos \left(x + x\right), 0.5\right)} \cdot 1 \]
            5. 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)))))