Given's Rotation SVD example

Percentage Accurate: 78.8% → 99.8%
Time: 5.1s
Alternatives: 6
Speedup: 0.5×

Specification

?
\[10^{-150} < \left|x\right| \land \left|x\right| < 10^{+150}\]
\[\begin{array}{l} \\ \sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \end{array} \]
(FPCore (p x)
 :precision binary64
 (sqrt (* 0.5 (+ 1.0 (/ x (sqrt (+ (* (* 4.0 p) p) (* x x))))))))
double code(double p, double x) {
	return sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x)))))));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

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

real(8) function code(p, x)
use fmin_fmax_functions
    real(8), intent (in) :: p
    real(8), intent (in) :: x
    code = sqrt((0.5d0 * (1.0d0 + (x / sqrt((((4.0d0 * p) * p) + (x * x)))))))
end function
public static double code(double p, double x) {
	return Math.sqrt((0.5 * (1.0 + (x / Math.sqrt((((4.0 * p) * p) + (x * x)))))));
}
def code(p, x):
	return math.sqrt((0.5 * (1.0 + (x / math.sqrt((((4.0 * p) * p) + (x * x)))))))
function code(p, x)
	return sqrt(Float64(0.5 * Float64(1.0 + Float64(x / sqrt(Float64(Float64(Float64(4.0 * p) * p) + Float64(x * x)))))))
end
function tmp = code(p, x)
	tmp = sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x)))))));
end
code[p_, x_] := N[Sqrt[N[(0.5 * N[(1.0 + N[(x / N[Sqrt[N[(N[(N[(4.0 * p), $MachinePrecision] * p), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)}
\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 6 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: 78.8% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \end{array} \]
(FPCore (p x)
 :precision binary64
 (sqrt (* 0.5 (+ 1.0 (/ x (sqrt (+ (* (* 4.0 p) p) (* x x))))))))
double code(double p, double x) {
	return sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x)))))));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

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

real(8) function code(p, x)
use fmin_fmax_functions
    real(8), intent (in) :: p
    real(8), intent (in) :: x
    code = sqrt((0.5d0 * (1.0d0 + (x / sqrt((((4.0d0 * p) * p) + (x * x)))))))
end function
public static double code(double p, double x) {
	return Math.sqrt((0.5 * (1.0 + (x / Math.sqrt((((4.0 * p) * p) + (x * x)))))));
}
def code(p, x):
	return math.sqrt((0.5 * (1.0 + (x / math.sqrt((((4.0 * p) * p) + (x * x)))))))
function code(p, x)
	return sqrt(Float64(0.5 * Float64(1.0 + Float64(x / sqrt(Float64(Float64(Float64(4.0 * p) * p) + Float64(x * x)))))))
end
function tmp = code(p, x)
	tmp = sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x)))))));
end
code[p_, x_] := N[Sqrt[N[(0.5 * N[(1.0 + N[(x / N[Sqrt[N[(N[(N[(4.0 * p), $MachinePrecision] * p), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)}
\end{array}

Alternative 1: 99.8% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \leq 2 \cdot 10^{-6}:\\ \;\;\;\;\frac{\left|p\right|}{-x}\\ \mathbf{else}:\\ \;\;\;\;e^{\log \left(\mathsf{fma}\left(\sqrt{\frac{1}{\mathsf{fma}\left(4 \cdot p, p, x \cdot x\right)}}, x, 1\right) \cdot 0.5\right) \cdot 0.5}\\ \end{array} \end{array} \]
(FPCore (p x)
 :precision binary64
 (if (<= (sqrt (* 0.5 (+ 1.0 (/ x (sqrt (+ (* (* 4.0 p) p) (* x x))))))) 2e-6)
   (/ (fabs p) (- x))
   (exp
    (*
     (log (* (fma (sqrt (/ 1.0 (fma (* 4.0 p) p (* x x)))) x 1.0) 0.5))
     0.5))))
double code(double p, double x) {
	double tmp;
	if (sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x))))))) <= 2e-6) {
		tmp = fabs(p) / -x;
	} else {
		tmp = exp((log((fma(sqrt((1.0 / fma((4.0 * p), p, (x * x)))), x, 1.0) * 0.5)) * 0.5));
	}
	return tmp;
}
function code(p, x)
	tmp = 0.0
	if (sqrt(Float64(0.5 * Float64(1.0 + Float64(x / sqrt(Float64(Float64(Float64(4.0 * p) * p) + Float64(x * x))))))) <= 2e-6)
		tmp = Float64(abs(p) / Float64(-x));
	else
		tmp = exp(Float64(log(Float64(fma(sqrt(Float64(1.0 / fma(Float64(4.0 * p), p, Float64(x * x)))), x, 1.0) * 0.5)) * 0.5));
	end
	return tmp
end
code[p_, x_] := If[LessEqual[N[Sqrt[N[(0.5 * N[(1.0 + N[(x / N[Sqrt[N[(N[(N[(4.0 * p), $MachinePrecision] * p), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], 2e-6], N[(N[Abs[p], $MachinePrecision] / (-x)), $MachinePrecision], N[Exp[N[(N[Log[N[(N[(N[Sqrt[N[(1.0 / N[(N[(4.0 * p), $MachinePrecision] * p + N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * x + 1.0), $MachinePrecision] * 0.5), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \leq 2 \cdot 10^{-6}:\\
\;\;\;\;\frac{\left|p\right|}{-x}\\

\mathbf{else}:\\
\;\;\;\;e^{\log \left(\mathsf{fma}\left(\sqrt{\frac{1}{\mathsf{fma}\left(4 \cdot p, p, x \cdot x\right)}}, x, 1\right) \cdot 0.5\right) \cdot 0.5}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x))))))) < 1.99999999999999991e-6

    1. Initial program 78.8%

      \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
    2. Taylor expanded in x around -inf

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

        \[\leadsto -1 \cdot \color{blue}{\frac{\sqrt{{p}^{2}}}{x}} \]
      2. lower-/.f64N/A

        \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{\color{blue}{x}} \]
      3. lower-sqrt.f64N/A

        \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{x} \]
      4. lower-pow.f6418.6

        \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{x} \]
    4. Applied rewrites18.6%

      \[\leadsto \color{blue}{-1 \cdot \frac{\sqrt{{p}^{2}}}{x}} \]
    5. Step-by-step derivation
      1. Applied rewrites27.4%

        \[\leadsto \color{blue}{\frac{\left|p\right|}{-x}} \]

      if 1.99999999999999991e-6 < (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))))))

      1. Initial program 78.8%

        \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
      2. Step-by-step derivation
        1. lift-/.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}}\right)} \]
        2. mult-flipN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{x \cdot \frac{1}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}}\right)} \]
        3. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\frac{1}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot x}\right)} \]
        4. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\frac{1}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot x}\right)} \]
        5. metadata-evalN/A

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

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \frac{\sqrt{1}}{\color{blue}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}} \cdot x\right)} \]
        7. sqrt-undivN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\sqrt{\frac{1}{\left(4 \cdot p\right) \cdot p + x \cdot x}}} \cdot x\right)} \]
        8. lower-sqrt.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\sqrt{\frac{1}{\left(4 \cdot p\right) \cdot p + x \cdot x}}} \cdot x\right)} \]
        9. lower-/.f6478.2

          \[\leadsto \sqrt{0.5 \cdot \left(1 + \sqrt{\color{blue}{\frac{1}{\left(4 \cdot p\right) \cdot p + x \cdot x}}} \cdot x\right)} \]
        10. lift-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \sqrt{\frac{1}{\color{blue}{\left(4 \cdot p\right) \cdot p + x \cdot x}}} \cdot x\right)} \]
        11. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \sqrt{\frac{1}{\color{blue}{\left(4 \cdot p\right) \cdot p} + x \cdot x}} \cdot x\right)} \]
        12. lower-fma.f6478.2

          \[\leadsto \sqrt{0.5 \cdot \left(1 + \sqrt{\frac{1}{\color{blue}{\mathsf{fma}\left(4 \cdot p, p, x \cdot x\right)}}} \cdot x\right)} \]
        13. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \sqrt{\frac{1}{\mathsf{fma}\left(\color{blue}{4 \cdot p}, p, x \cdot x\right)}} \cdot x\right)} \]
        14. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \sqrt{\frac{1}{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}} \cdot x\right)} \]
        15. lower-*.f6478.2

          \[\leadsto \sqrt{0.5 \cdot \left(1 + \sqrt{\frac{1}{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}} \cdot x\right)} \]
      3. Applied rewrites78.2%

        \[\leadsto \sqrt{0.5 \cdot \left(1 + \color{blue}{\sqrt{\frac{1}{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}} \cdot x}\right)} \]
      4. Step-by-step derivation
        1. lift-sqrt.f64N/A

          \[\leadsto \color{blue}{\sqrt{\frac{1}{2} \cdot \left(1 + \sqrt{\frac{1}{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}} \cdot x\right)}} \]
        2. pow1/2N/A

          \[\leadsto \color{blue}{{\left(\frac{1}{2} \cdot \left(1 + \sqrt{\frac{1}{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}} \cdot x\right)\right)}^{\frac{1}{2}}} \]
        3. pow-to-expN/A

          \[\leadsto \color{blue}{e^{\log \left(\frac{1}{2} \cdot \left(1 + \sqrt{\frac{1}{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}} \cdot x\right)\right) \cdot \frac{1}{2}}} \]
        4. lower-unsound-exp.f64N/A

          \[\leadsto \color{blue}{e^{\log \left(\frac{1}{2} \cdot \left(1 + \sqrt{\frac{1}{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}} \cdot x\right)\right) \cdot \frac{1}{2}}} \]
        5. lower-unsound-*.f64N/A

          \[\leadsto e^{\color{blue}{\log \left(\frac{1}{2} \cdot \left(1 + \sqrt{\frac{1}{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}} \cdot x\right)\right) \cdot \frac{1}{2}}} \]
      5. Applied rewrites75.5%

        \[\leadsto \color{blue}{e^{\log \left(\mathsf{fma}\left(\sqrt{\frac{1}{\mathsf{fma}\left(4 \cdot p, p, x \cdot x\right)}}, x, 1\right) \cdot 0.5\right) \cdot 0.5}} \]
    6. Recombined 2 regimes into one program.
    7. Add Preprocessing

    Alternative 2: 99.8% accurate, 0.5× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \leq 2 \cdot 10^{-6}:\\ \;\;\;\;\frac{\left|p\right|}{-x}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{0.5}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, x, 0.5\right)}\\ \end{array} \end{array} \]
    (FPCore (p x)
     :precision binary64
     (if (<= (sqrt (* 0.5 (+ 1.0 (/ x (sqrt (+ (* (* 4.0 p) p) (* x x))))))) 2e-6)
       (/ (fabs p) (- x))
       (sqrt (fma (/ 0.5 (sqrt (fma (* p 4.0) p (* x x)))) x 0.5))))
    double code(double p, double x) {
    	double tmp;
    	if (sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x))))))) <= 2e-6) {
    		tmp = fabs(p) / -x;
    	} else {
    		tmp = sqrt(fma((0.5 / sqrt(fma((p * 4.0), p, (x * x)))), x, 0.5));
    	}
    	return tmp;
    }
    
    function code(p, x)
    	tmp = 0.0
    	if (sqrt(Float64(0.5 * Float64(1.0 + Float64(x / sqrt(Float64(Float64(Float64(4.0 * p) * p) + Float64(x * x))))))) <= 2e-6)
    		tmp = Float64(abs(p) / Float64(-x));
    	else
    		tmp = sqrt(fma(Float64(0.5 / sqrt(fma(Float64(p * 4.0), p, Float64(x * x)))), x, 0.5));
    	end
    	return tmp
    end
    
    code[p_, x_] := If[LessEqual[N[Sqrt[N[(0.5 * N[(1.0 + N[(x / N[Sqrt[N[(N[(N[(4.0 * p), $MachinePrecision] * p), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], 2e-6], N[(N[Abs[p], $MachinePrecision] / (-x)), $MachinePrecision], N[Sqrt[N[(N[(0.5 / N[Sqrt[N[(N[(p * 4.0), $MachinePrecision] * p + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * x + 0.5), $MachinePrecision]], $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \leq 2 \cdot 10^{-6}:\\
    \;\;\;\;\frac{\left|p\right|}{-x}\\
    
    \mathbf{else}:\\
    \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{0.5}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, x, 0.5\right)}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x))))))) < 1.99999999999999991e-6

      1. Initial program 78.8%

        \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
      2. Taylor expanded in x around -inf

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

          \[\leadsto -1 \cdot \color{blue}{\frac{\sqrt{{p}^{2}}}{x}} \]
        2. lower-/.f64N/A

          \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{\color{blue}{x}} \]
        3. lower-sqrt.f64N/A

          \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{x} \]
        4. lower-pow.f6418.6

          \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{x} \]
      4. Applied rewrites18.6%

        \[\leadsto \color{blue}{-1 \cdot \frac{\sqrt{{p}^{2}}}{x}} \]
      5. Step-by-step derivation
        1. Applied rewrites27.4%

          \[\leadsto \color{blue}{\frac{\left|p\right|}{-x}} \]

        if 1.99999999999999991e-6 < (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))))))

        1. Initial program 78.8%

          \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
        2. Step-by-step derivation
          1. lift-*.f64N/A

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

            \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)}} \]
          3. +-commutativeN/A

            \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} + 1\right)}} \]
          4. distribute-rgt-inN/A

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

            \[\leadsto \sqrt{\color{blue}{\frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}} \cdot \frac{1}{2} + 1 \cdot \frac{1}{2}} \]
          6. associate-*l/N/A

            \[\leadsto \sqrt{\color{blue}{\frac{x \cdot \frac{1}{2}}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}} + 1 \cdot \frac{1}{2}} \]
          7. associate-/l*N/A

            \[\leadsto \sqrt{\color{blue}{x \cdot \frac{\frac{1}{2}}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}} + 1 \cdot \frac{1}{2}} \]
          8. *-commutativeN/A

            \[\leadsto \sqrt{\color{blue}{\frac{\frac{1}{2}}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot x} + 1 \cdot \frac{1}{2}} \]
          9. metadata-evalN/A

            \[\leadsto \sqrt{\frac{\frac{1}{2}}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot x + \color{blue}{\frac{1}{2}}} \]
          10. lower-fma.f64N/A

            \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{\frac{1}{2}}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}, x, \frac{1}{2}\right)}} \]
        3. Applied rewrites75.5%

          \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{0.5}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, x, 0.5\right)}} \]
      6. Recombined 2 regimes into one program.
      7. Add Preprocessing

      Alternative 3: 98.7% accurate, 0.4× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)}\\ \mathbf{if}\;t\_0 \leq 2 \cdot 10^{-6}:\\ \;\;\;\;\frac{\left|p\right|}{-x}\\ \mathbf{elif}\;t\_0 \leq 0.7073982243349322:\\ \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{x}{p}, 0.25, 0.5\right)}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{0.5 \cdot 2}\\ \end{array} \end{array} \]
      (FPCore (p x)
       :precision binary64
       (let* ((t_0 (sqrt (* 0.5 (+ 1.0 (/ x (sqrt (+ (* (* 4.0 p) p) (* x x)))))))))
         (if (<= t_0 2e-6)
           (/ (fabs p) (- x))
           (if (<= t_0 0.7073982243349322)
             (sqrt (fma (/ x p) 0.25 0.5))
             (sqrt (* 0.5 2.0))))))
      double code(double p, double x) {
      	double t_0 = sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x)))))));
      	double tmp;
      	if (t_0 <= 2e-6) {
      		tmp = fabs(p) / -x;
      	} else if (t_0 <= 0.7073982243349322) {
      		tmp = sqrt(fma((x / p), 0.25, 0.5));
      	} else {
      		tmp = sqrt((0.5 * 2.0));
      	}
      	return tmp;
      }
      
      function code(p, x)
      	t_0 = sqrt(Float64(0.5 * Float64(1.0 + Float64(x / sqrt(Float64(Float64(Float64(4.0 * p) * p) + Float64(x * x)))))))
      	tmp = 0.0
      	if (t_0 <= 2e-6)
      		tmp = Float64(abs(p) / Float64(-x));
      	elseif (t_0 <= 0.7073982243349322)
      		tmp = sqrt(fma(Float64(x / p), 0.25, 0.5));
      	else
      		tmp = sqrt(Float64(0.5 * 2.0));
      	end
      	return tmp
      end
      
      code[p_, x_] := Block[{t$95$0 = N[Sqrt[N[(0.5 * N[(1.0 + N[(x / N[Sqrt[N[(N[(N[(4.0 * p), $MachinePrecision] * p), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$0, 2e-6], N[(N[Abs[p], $MachinePrecision] / (-x)), $MachinePrecision], If[LessEqual[t$95$0, 0.7073982243349322], N[Sqrt[N[(N[(x / p), $MachinePrecision] * 0.25 + 0.5), $MachinePrecision]], $MachinePrecision], N[Sqrt[N[(0.5 * 2.0), $MachinePrecision]], $MachinePrecision]]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)}\\
      \mathbf{if}\;t\_0 \leq 2 \cdot 10^{-6}:\\
      \;\;\;\;\frac{\left|p\right|}{-x}\\
      
      \mathbf{elif}\;t\_0 \leq 0.7073982243349322:\\
      \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{x}{p}, 0.25, 0.5\right)}\\
      
      \mathbf{else}:\\
      \;\;\;\;\sqrt{0.5 \cdot 2}\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x))))))) < 1.99999999999999991e-6

        1. Initial program 78.8%

          \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
        2. Taylor expanded in x around -inf

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

            \[\leadsto -1 \cdot \color{blue}{\frac{\sqrt{{p}^{2}}}{x}} \]
          2. lower-/.f64N/A

            \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{\color{blue}{x}} \]
          3. lower-sqrt.f64N/A

            \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{x} \]
          4. lower-pow.f6418.6

            \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{x} \]
        4. Applied rewrites18.6%

          \[\leadsto \color{blue}{-1 \cdot \frac{\sqrt{{p}^{2}}}{x}} \]
        5. Step-by-step derivation
          1. Applied rewrites27.4%

            \[\leadsto \color{blue}{\frac{\left|p\right|}{-x}} \]

          if 1.99999999999999991e-6 < (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x))))))) < 0.70739822433493216

          1. Initial program 78.8%

            \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
          2. Taylor expanded in p around inf

            \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \frac{1}{4} \cdot \frac{x}{p}}} \]
          3. Step-by-step derivation
            1. lower-+.f64N/A

              \[\leadsto \sqrt{\frac{1}{2} + \color{blue}{\frac{1}{4} \cdot \frac{x}{p}}} \]
            2. lower-*.f64N/A

              \[\leadsto \sqrt{\frac{1}{2} + \frac{1}{4} \cdot \color{blue}{\frac{x}{p}}} \]
            3. lower-/.f6450.9

              \[\leadsto \sqrt{0.5 + 0.25 \cdot \frac{x}{\color{blue}{p}}} \]
          4. Applied rewrites50.9%

            \[\leadsto \sqrt{\color{blue}{0.5 + 0.25 \cdot \frac{x}{p}}} \]
          5. Step-by-step derivation
            1. lift-+.f64N/A

              \[\leadsto \sqrt{\frac{1}{2} + \color{blue}{\frac{1}{4} \cdot \frac{x}{p}}} \]
            2. +-commutativeN/A

              \[\leadsto \sqrt{\frac{1}{4} \cdot \frac{x}{p} + \color{blue}{\frac{1}{2}}} \]
            3. lift-*.f64N/A

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

              \[\leadsto \sqrt{\frac{x}{p} \cdot \frac{1}{4} + \frac{1}{2}} \]
            5. lower-fma.f6450.9

              \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{p}, \color{blue}{0.25}, 0.5\right)} \]
          6. Applied rewrites50.9%

            \[\leadsto \color{blue}{\sqrt{\mathsf{fma}\left(\frac{x}{p}, 0.25, 0.5\right)}} \]

          if 0.70739822433493216 < (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))))))

          1. Initial program 78.8%

            \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
          2. Taylor expanded in x around inf

            \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{2}} \]
          3. Step-by-step derivation
            1. Applied rewrites35.5%

              \[\leadsto \sqrt{0.5 \cdot \color{blue}{2}} \]
          4. Recombined 3 regimes into one program.
          5. Add Preprocessing

          Alternative 4: 98.5% accurate, 0.4× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)}\\ \mathbf{if}\;t\_0 \leq 2 \cdot 10^{-6}:\\ \;\;\;\;\frac{\left|p\right|}{-x}\\ \mathbf{elif}\;t\_0 \leq 0.7073982243349322:\\ \;\;\;\;\sqrt{0.5}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{0.5 \cdot 2}\\ \end{array} \end{array} \]
          (FPCore (p x)
           :precision binary64
           (let* ((t_0 (sqrt (* 0.5 (+ 1.0 (/ x (sqrt (+ (* (* 4.0 p) p) (* x x)))))))))
             (if (<= t_0 2e-6)
               (/ (fabs p) (- x))
               (if (<= t_0 0.7073982243349322) (sqrt 0.5) (sqrt (* 0.5 2.0))))))
          double code(double p, double x) {
          	double t_0 = sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x)))))));
          	double tmp;
          	if (t_0 <= 2e-6) {
          		tmp = fabs(p) / -x;
          	} else if (t_0 <= 0.7073982243349322) {
          		tmp = sqrt(0.5);
          	} else {
          		tmp = sqrt((0.5 * 2.0));
          	}
          	return tmp;
          }
          
          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(p, x)
          use fmin_fmax_functions
              real(8), intent (in) :: p
              real(8), intent (in) :: x
              real(8) :: t_0
              real(8) :: tmp
              t_0 = sqrt((0.5d0 * (1.0d0 + (x / sqrt((((4.0d0 * p) * p) + (x * x)))))))
              if (t_0 <= 2d-6) then
                  tmp = abs(p) / -x
              else if (t_0 <= 0.7073982243349322d0) then
                  tmp = sqrt(0.5d0)
              else
                  tmp = sqrt((0.5d0 * 2.0d0))
              end if
              code = tmp
          end function
          
          public static double code(double p, double x) {
          	double t_0 = Math.sqrt((0.5 * (1.0 + (x / Math.sqrt((((4.0 * p) * p) + (x * x)))))));
          	double tmp;
          	if (t_0 <= 2e-6) {
          		tmp = Math.abs(p) / -x;
          	} else if (t_0 <= 0.7073982243349322) {
          		tmp = Math.sqrt(0.5);
          	} else {
          		tmp = Math.sqrt((0.5 * 2.0));
          	}
          	return tmp;
          }
          
          def code(p, x):
          	t_0 = math.sqrt((0.5 * (1.0 + (x / math.sqrt((((4.0 * p) * p) + (x * x)))))))
          	tmp = 0
          	if t_0 <= 2e-6:
          		tmp = math.fabs(p) / -x
          	elif t_0 <= 0.7073982243349322:
          		tmp = math.sqrt(0.5)
          	else:
          		tmp = math.sqrt((0.5 * 2.0))
          	return tmp
          
          function code(p, x)
          	t_0 = sqrt(Float64(0.5 * Float64(1.0 + Float64(x / sqrt(Float64(Float64(Float64(4.0 * p) * p) + Float64(x * x)))))))
          	tmp = 0.0
          	if (t_0 <= 2e-6)
          		tmp = Float64(abs(p) / Float64(-x));
          	elseif (t_0 <= 0.7073982243349322)
          		tmp = sqrt(0.5);
          	else
          		tmp = sqrt(Float64(0.5 * 2.0));
          	end
          	return tmp
          end
          
          function tmp_2 = code(p, x)
          	t_0 = sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x)))))));
          	tmp = 0.0;
          	if (t_0 <= 2e-6)
          		tmp = abs(p) / -x;
          	elseif (t_0 <= 0.7073982243349322)
          		tmp = sqrt(0.5);
          	else
          		tmp = sqrt((0.5 * 2.0));
          	end
          	tmp_2 = tmp;
          end
          
          code[p_, x_] := Block[{t$95$0 = N[Sqrt[N[(0.5 * N[(1.0 + N[(x / N[Sqrt[N[(N[(N[(4.0 * p), $MachinePrecision] * p), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$0, 2e-6], N[(N[Abs[p], $MachinePrecision] / (-x)), $MachinePrecision], If[LessEqual[t$95$0, 0.7073982243349322], N[Sqrt[0.5], $MachinePrecision], N[Sqrt[N[(0.5 * 2.0), $MachinePrecision]], $MachinePrecision]]]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          t_0 := \sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)}\\
          \mathbf{if}\;t\_0 \leq 2 \cdot 10^{-6}:\\
          \;\;\;\;\frac{\left|p\right|}{-x}\\
          
          \mathbf{elif}\;t\_0 \leq 0.7073982243349322:\\
          \;\;\;\;\sqrt{0.5}\\
          
          \mathbf{else}:\\
          \;\;\;\;\sqrt{0.5 \cdot 2}\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 3 regimes
          2. if (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x))))))) < 1.99999999999999991e-6

            1. Initial program 78.8%

              \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
            2. Taylor expanded in x around -inf

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

                \[\leadsto -1 \cdot \color{blue}{\frac{\sqrt{{p}^{2}}}{x}} \]
              2. lower-/.f64N/A

                \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{\color{blue}{x}} \]
              3. lower-sqrt.f64N/A

                \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{x} \]
              4. lower-pow.f6418.6

                \[\leadsto -1 \cdot \frac{\sqrt{{p}^{2}}}{x} \]
            4. Applied rewrites18.6%

              \[\leadsto \color{blue}{-1 \cdot \frac{\sqrt{{p}^{2}}}{x}} \]
            5. Step-by-step derivation
              1. Applied rewrites27.4%

                \[\leadsto \color{blue}{\frac{\left|p\right|}{-x}} \]

              if 1.99999999999999991e-6 < (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x))))))) < 0.70739822433493216

              1. Initial program 78.8%

                \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
              2. Taylor expanded in p around inf

                \[\leadsto \sqrt{\color{blue}{\frac{1}{2}}} \]
              3. Step-by-step derivation
                1. Applied rewrites55.4%

                  \[\leadsto \sqrt{\color{blue}{0.5}} \]

                if 0.70739822433493216 < (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))))))

                1. Initial program 78.8%

                  \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
                2. Taylor expanded in x around inf

                  \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{2}} \]
                3. Step-by-step derivation
                  1. Applied rewrites35.5%

                    \[\leadsto \sqrt{0.5 \cdot \color{blue}{2}} \]
                4. Recombined 3 regimes into one program.
                5. Add Preprocessing

                Alternative 5: 74.7% accurate, 0.7× speedup?

                \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \leq 0.85:\\ \;\;\;\;\sqrt{0.5}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{0.5 \cdot 2}\\ \end{array} \end{array} \]
                (FPCore (p x)
                 :precision binary64
                 (if (<= (sqrt (* 0.5 (+ 1.0 (/ x (sqrt (+ (* (* 4.0 p) p) (* x x))))))) 0.85)
                   (sqrt 0.5)
                   (sqrt (* 0.5 2.0))))
                double code(double p, double x) {
                	double tmp;
                	if (sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x))))))) <= 0.85) {
                		tmp = sqrt(0.5);
                	} else {
                		tmp = sqrt((0.5 * 2.0));
                	}
                	return tmp;
                }
                
                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(p, x)
                use fmin_fmax_functions
                    real(8), intent (in) :: p
                    real(8), intent (in) :: x
                    real(8) :: tmp
                    if (sqrt((0.5d0 * (1.0d0 + (x / sqrt((((4.0d0 * p) * p) + (x * x))))))) <= 0.85d0) then
                        tmp = sqrt(0.5d0)
                    else
                        tmp = sqrt((0.5d0 * 2.0d0))
                    end if
                    code = tmp
                end function
                
                public static double code(double p, double x) {
                	double tmp;
                	if (Math.sqrt((0.5 * (1.0 + (x / Math.sqrt((((4.0 * p) * p) + (x * x))))))) <= 0.85) {
                		tmp = Math.sqrt(0.5);
                	} else {
                		tmp = Math.sqrt((0.5 * 2.0));
                	}
                	return tmp;
                }
                
                def code(p, x):
                	tmp = 0
                	if math.sqrt((0.5 * (1.0 + (x / math.sqrt((((4.0 * p) * p) + (x * x))))))) <= 0.85:
                		tmp = math.sqrt(0.5)
                	else:
                		tmp = math.sqrt((0.5 * 2.0))
                	return tmp
                
                function code(p, x)
                	tmp = 0.0
                	if (sqrt(Float64(0.5 * Float64(1.0 + Float64(x / sqrt(Float64(Float64(Float64(4.0 * p) * p) + Float64(x * x))))))) <= 0.85)
                		tmp = sqrt(0.5);
                	else
                		tmp = sqrt(Float64(0.5 * 2.0));
                	end
                	return tmp
                end
                
                function tmp_2 = code(p, x)
                	tmp = 0.0;
                	if (sqrt((0.5 * (1.0 + (x / sqrt((((4.0 * p) * p) + (x * x))))))) <= 0.85)
                		tmp = sqrt(0.5);
                	else
                		tmp = sqrt((0.5 * 2.0));
                	end
                	tmp_2 = tmp;
                end
                
                code[p_, x_] := If[LessEqual[N[Sqrt[N[(0.5 * N[(1.0 + N[(x / N[Sqrt[N[(N[(N[(4.0 * p), $MachinePrecision] * p), $MachinePrecision] + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], 0.85], N[Sqrt[0.5], $MachinePrecision], N[Sqrt[N[(0.5 * 2.0), $MachinePrecision]], $MachinePrecision]]
                
                \begin{array}{l}
                
                \\
                \begin{array}{l}
                \mathbf{if}\;\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \leq 0.85:\\
                \;\;\;\;\sqrt{0.5}\\
                
                \mathbf{else}:\\
                \;\;\;\;\sqrt{0.5 \cdot 2}\\
                
                
                \end{array}
                \end{array}
                
                Derivation
                1. Split input into 2 regimes
                2. if (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x))))))) < 0.849999999999999978

                  1. Initial program 78.8%

                    \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
                  2. Taylor expanded in p around inf

                    \[\leadsto \sqrt{\color{blue}{\frac{1}{2}}} \]
                  3. Step-by-step derivation
                    1. Applied rewrites55.4%

                      \[\leadsto \sqrt{\color{blue}{0.5}} \]

                    if 0.849999999999999978 < (sqrt.f64 (*.f64 #s(literal 1/2 binary64) (+.f64 #s(literal 1 binary64) (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))))))

                    1. Initial program 78.8%

                      \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
                    2. Taylor expanded in x around inf

                      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{2}} \]
                    3. Step-by-step derivation
                      1. Applied rewrites35.5%

                        \[\leadsto \sqrt{0.5 \cdot \color{blue}{2}} \]
                    4. Recombined 2 regimes into one program.
                    5. Add Preprocessing

                    Alternative 6: 55.4% accurate, 9.1× speedup?

                    \[\begin{array}{l} \\ \sqrt{0.5} \end{array} \]
                    (FPCore (p x) :precision binary64 (sqrt 0.5))
                    double code(double p, double x) {
                    	return sqrt(0.5);
                    }
                    
                    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(p, x)
                    use fmin_fmax_functions
                        real(8), intent (in) :: p
                        real(8), intent (in) :: x
                        code = sqrt(0.5d0)
                    end function
                    
                    public static double code(double p, double x) {
                    	return Math.sqrt(0.5);
                    }
                    
                    def code(p, x):
                    	return math.sqrt(0.5)
                    
                    function code(p, x)
                    	return sqrt(0.5)
                    end
                    
                    function tmp = code(p, x)
                    	tmp = sqrt(0.5);
                    end
                    
                    code[p_, x_] := N[Sqrt[0.5], $MachinePrecision]
                    
                    \begin{array}{l}
                    
                    \\
                    \sqrt{0.5}
                    \end{array}
                    
                    Derivation
                    1. Initial program 78.8%

                      \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
                    2. Taylor expanded in p around inf

                      \[\leadsto \sqrt{\color{blue}{\frac{1}{2}}} \]
                    3. Step-by-step derivation
                      1. Applied rewrites55.4%

                        \[\leadsto \sqrt{\color{blue}{0.5}} \]
                      2. Add Preprocessing

                      Developer Target 1: 78.8% accurate, 0.8× speedup?

                      \[\begin{array}{l} \\ \sqrt{0.5 + \frac{\mathsf{copysign}\left(0.5, x\right)}{\mathsf{hypot}\left(1, \frac{2 \cdot p}{x}\right)}} \end{array} \]
                      (FPCore (p x)
                       :precision binary64
                       (sqrt (+ 0.5 (/ (copysign 0.5 x) (hypot 1.0 (/ (* 2.0 p) x))))))
                      double code(double p, double x) {
                      	return sqrt((0.5 + (copysign(0.5, x) / hypot(1.0, ((2.0 * p) / x)))));
                      }
                      
                      public static double code(double p, double x) {
                      	return Math.sqrt((0.5 + (Math.copySign(0.5, x) / Math.hypot(1.0, ((2.0 * p) / x)))));
                      }
                      
                      def code(p, x):
                      	return math.sqrt((0.5 + (math.copysign(0.5, x) / math.hypot(1.0, ((2.0 * p) / x)))))
                      
                      function code(p, x)
                      	return sqrt(Float64(0.5 + Float64(copysign(0.5, x) / hypot(1.0, Float64(Float64(2.0 * p) / x)))))
                      end
                      
                      function tmp = code(p, x)
                      	tmp = sqrt((0.5 + ((sign(x) * abs(0.5)) / hypot(1.0, ((2.0 * p) / x)))));
                      end
                      
                      code[p_, x_] := N[Sqrt[N[(0.5 + N[(N[With[{TMP1 = Abs[0.5], TMP2 = Sign[x]}, TMP1 * If[TMP2 == 0, 1, TMP2]], $MachinePrecision] / N[Sqrt[1.0 ^ 2 + N[(N[(2.0 * p), $MachinePrecision] / x), $MachinePrecision] ^ 2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
                      
                      \begin{array}{l}
                      
                      \\
                      \sqrt{0.5 + \frac{\mathsf{copysign}\left(0.5, x\right)}{\mathsf{hypot}\left(1, \frac{2 \cdot p}{x}\right)}}
                      \end{array}
                      

                      Reproduce

                      ?
                      herbie shell --seed 2025159 
                      (FPCore (p x)
                        :name "Given's Rotation SVD example"
                        :precision binary64
                        :pre (and (< 1e-150 (fabs x)) (< (fabs x) 1e+150))
                      
                        :alt
                        (! :herbie-platform c (sqrt (+ 1/2 (/ (copysign 1/2 x) (hypot 1 (/ (* 2 p) x))))))
                      
                        (sqrt (* 0.5 (+ 1.0 (/ x (sqrt (+ (* (* 4.0 p) p) (* x x))))))))