Given's Rotation SVD example

Percentage Accurate: 79.5% → 99.9%
Time: 9.5s
Alternatives: 5
Speedup: 0.6×

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)))))));
}
real(8) function code(p, x)
    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}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 5 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: 79.5% 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)))))));
}
real(8) function code(p, x)
    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: 99.9% accurate, 0.6× speedup?

\[\begin{array}{l} p_m = \left|p\right| \\ \begin{array}{l} \mathbf{if}\;\frac{x}{\sqrt{x \cdot x + \left(p\_m \cdot 4\right) \cdot p\_m}} \leq -0.99999:\\ \;\;\;\;\frac{-p\_m}{x}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{0.5}{\sqrt{\mathsf{fma}\left(p\_m \cdot 4, p\_m, x \cdot x\right)}}, x, 0.5\right)}\\ \end{array} \end{array} \]
p_m = (fabs.f64 p)
(FPCore (p_m x)
 :precision binary64
 (if (<= (/ x (sqrt (+ (* x x) (* (* p_m 4.0) p_m)))) -0.99999)
   (/ (- p_m) x)
   (sqrt (fma (/ 0.5 (sqrt (fma (* p_m 4.0) p_m (* x x)))) x 0.5))))
p_m = fabs(p);
double code(double p_m, double x) {
	double tmp;
	if ((x / sqrt(((x * x) + ((p_m * 4.0) * p_m)))) <= -0.99999) {
		tmp = -p_m / x;
	} else {
		tmp = sqrt(fma((0.5 / sqrt(fma((p_m * 4.0), p_m, (x * x)))), x, 0.5));
	}
	return tmp;
}
p_m = abs(p)
function code(p_m, x)
	tmp = 0.0
	if (Float64(x / sqrt(Float64(Float64(x * x) + Float64(Float64(p_m * 4.0) * p_m)))) <= -0.99999)
		tmp = Float64(Float64(-p_m) / x);
	else
		tmp = sqrt(fma(Float64(0.5 / sqrt(fma(Float64(p_m * 4.0), p_m, Float64(x * x)))), x, 0.5));
	end
	return tmp
end
p_m = N[Abs[p], $MachinePrecision]
code[p$95$m_, x_] := If[LessEqual[N[(x / N[Sqrt[N[(N[(x * x), $MachinePrecision] + N[(N[(p$95$m * 4.0), $MachinePrecision] * p$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], -0.99999], N[((-p$95$m) / x), $MachinePrecision], N[Sqrt[N[(N[(0.5 / N[Sqrt[N[(N[(p$95$m * 4.0), $MachinePrecision] * p$95$m + N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * x + 0.5), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
p_m = \left|p\right|

\\
\begin{array}{l}
\mathbf{if}\;\frac{x}{\sqrt{x \cdot x + \left(p\_m \cdot 4\right) \cdot p\_m}} \leq -0.99999:\\
\;\;\;\;\frac{-p\_m}{x}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))) < -0.999990000000000046

    1. Initial program 12.7%

      \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
    2. Add Preprocessing
    3. 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. metadata-evalN/A

        \[\leadsto \sqrt{\frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot \frac{1}{2} + \color{blue}{\frac{1}{2}}} \]
      6. lower-fma.f6412.7

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

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

        \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\color{blue}{\left(4 \cdot p\right) \cdot p} + x \cdot x}}, \frac{1}{2}, \frac{1}{2}\right)} \]
      9. lower-fma.f6412.7

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

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

        \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, \frac{1}{2}, \frac{1}{2}\right)} \]
      12. lower-*.f6412.7

        \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, 0.5, 0.5\right)} \]
    4. Applied rewrites12.7%

      \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, 0.5, 0.5\right)}} \]
    5. Taylor expanded in x around -inf

      \[\leadsto \color{blue}{-1 \cdot \frac{p}{x}} \]
    6. Step-by-step derivation
      1. associate-*r/N/A

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

        \[\leadsto \color{blue}{\frac{-1 \cdot p}{x}} \]
      3. mul-1-negN/A

        \[\leadsto \frac{\color{blue}{\mathsf{neg}\left(p\right)}}{x} \]
      4. lower-neg.f6448.9

        \[\leadsto \frac{\color{blue}{-p}}{x} \]
    7. Applied rewrites48.9%

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

    if -0.999990000000000046 < (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x))))

    1. Initial program 99.8%

      \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
    2. Add Preprocessing
    3. 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-lft-inN/A

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

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

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

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

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

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

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

        \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{1}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot \frac{1}{2}, x, \frac{1}{2}\right)}} \]
    4. Applied rewrites99.8%

      \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{0.5}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, x, 0.5\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification88.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x}{\sqrt{x \cdot x + \left(p \cdot 4\right) \cdot p}} \leq -0.99999:\\ \;\;\;\;\frac{-p}{x}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{0.5}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, x, 0.5\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 99.0% accurate, 0.5× speedup?

\[\begin{array}{l} p_m = \left|p\right| \\ \begin{array}{l} t_0 := \frac{x}{\sqrt{x \cdot x + \left(p\_m \cdot 4\right) \cdot p\_m}}\\ \mathbf{if}\;t\_0 \leq -0.6:\\ \;\;\;\;\frac{-p\_m}{x}\\ \mathbf{elif}\;t\_0 \leq 4 \cdot 10^{-7}:\\ \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{x}{p\_m}, 0.25, 0.5\right)}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
p_m = (fabs.f64 p)
(FPCore (p_m x)
 :precision binary64
 (let* ((t_0 (/ x (sqrt (+ (* x x) (* (* p_m 4.0) p_m))))))
   (if (<= t_0 -0.6)
     (/ (- p_m) x)
     (if (<= t_0 4e-7) (sqrt (fma (/ x p_m) 0.25 0.5)) 1.0))))
p_m = fabs(p);
double code(double p_m, double x) {
	double t_0 = x / sqrt(((x * x) + ((p_m * 4.0) * p_m)));
	double tmp;
	if (t_0 <= -0.6) {
		tmp = -p_m / x;
	} else if (t_0 <= 4e-7) {
		tmp = sqrt(fma((x / p_m), 0.25, 0.5));
	} else {
		tmp = 1.0;
	}
	return tmp;
}
p_m = abs(p)
function code(p_m, x)
	t_0 = Float64(x / sqrt(Float64(Float64(x * x) + Float64(Float64(p_m * 4.0) * p_m))))
	tmp = 0.0
	if (t_0 <= -0.6)
		tmp = Float64(Float64(-p_m) / x);
	elseif (t_0 <= 4e-7)
		tmp = sqrt(fma(Float64(x / p_m), 0.25, 0.5));
	else
		tmp = 1.0;
	end
	return tmp
end
p_m = N[Abs[p], $MachinePrecision]
code[p$95$m_, x_] := Block[{t$95$0 = N[(x / N[Sqrt[N[(N[(x * x), $MachinePrecision] + N[(N[(p$95$m * 4.0), $MachinePrecision] * p$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.6], N[((-p$95$m) / x), $MachinePrecision], If[LessEqual[t$95$0, 4e-7], N[Sqrt[N[(N[(x / p$95$m), $MachinePrecision] * 0.25 + 0.5), $MachinePrecision]], $MachinePrecision], 1.0]]]
\begin{array}{l}
p_m = \left|p\right|

\\
\begin{array}{l}
t_0 := \frac{x}{\sqrt{x \cdot x + \left(p\_m \cdot 4\right) \cdot p\_m}}\\
\mathbf{if}\;t\_0 \leq -0.6:\\
\;\;\;\;\frac{-p\_m}{x}\\

\mathbf{elif}\;t\_0 \leq 4 \cdot 10^{-7}:\\
\;\;\;\;\sqrt{\mathsf{fma}\left(\frac{x}{p\_m}, 0.25, 0.5\right)}\\

\mathbf{else}:\\
\;\;\;\;1\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))) < -0.599999999999999978

    1. Initial program 16.3%

      \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
    2. Add Preprocessing
    3. 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. metadata-evalN/A

        \[\leadsto \sqrt{\frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot \frac{1}{2} + \color{blue}{\frac{1}{2}}} \]
      6. lower-fma.f6416.3

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

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

        \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\color{blue}{\left(4 \cdot p\right) \cdot p} + x \cdot x}}, \frac{1}{2}, \frac{1}{2}\right)} \]
      9. lower-fma.f6416.3

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

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

        \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, \frac{1}{2}, \frac{1}{2}\right)} \]
      12. lower-*.f6416.3

        \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, 0.5, 0.5\right)} \]
    4. Applied rewrites16.3%

      \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, 0.5, 0.5\right)}} \]
    5. Taylor expanded in x around -inf

      \[\leadsto \color{blue}{-1 \cdot \frac{p}{x}} \]
    6. Step-by-step derivation
      1. associate-*r/N/A

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

        \[\leadsto \color{blue}{\frac{-1 \cdot p}{x}} \]
      3. mul-1-negN/A

        \[\leadsto \frac{\color{blue}{\mathsf{neg}\left(p\right)}}{x} \]
      4. lower-neg.f6446.9

        \[\leadsto \frac{\color{blue}{-p}}{x} \]
    7. Applied rewrites46.9%

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

    if -0.599999999999999978 < (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))) < 3.9999999999999998e-7

    1. Initial program 100.0%

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

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

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

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

        \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{x}{p}, \frac{1}{4}, \frac{1}{2}\right)}} \]
      4. lower-/.f6497.8

        \[\leadsto \sqrt{\mathsf{fma}\left(\color{blue}{\frac{x}{p}}, 0.25, 0.5\right)} \]
    5. Applied rewrites97.8%

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

    if 3.9999999999999998e-7 < (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x))))

    1. Initial program 100.0%

      \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
    2. Add Preprocessing
    3. 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. metadata-evalN/A

        \[\leadsto \sqrt{\frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot \frac{1}{2} + \color{blue}{\frac{1}{2}}} \]
      6. lower-fma.f64100.0

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

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

        \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\color{blue}{\left(4 \cdot p\right) \cdot p} + x \cdot x}}, \frac{1}{2}, \frac{1}{2}\right)} \]
      9. lower-fma.f64100.0

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

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

        \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, \frac{1}{2}, \frac{1}{2}\right)} \]
      12. lower-*.f64100.0

        \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, 0.5, 0.5\right)} \]
    4. Applied rewrites100.0%

      \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, 0.5, 0.5\right)}} \]
    5. Taylor expanded in p around 0

      \[\leadsto \color{blue}{1} \]
    6. Step-by-step derivation
      1. Applied rewrites100.0%

        \[\leadsto \color{blue}{1} \]
    7. Recombined 3 regimes into one program.
    8. Final simplification86.1%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x}{\sqrt{x \cdot x + \left(p \cdot 4\right) \cdot p}} \leq -0.6:\\ \;\;\;\;\frac{-p}{x}\\ \mathbf{elif}\;\frac{x}{\sqrt{x \cdot x + \left(p \cdot 4\right) \cdot p}} \leq 4 \cdot 10^{-7}:\\ \;\;\;\;\sqrt{\mathsf{fma}\left(\frac{x}{p}, 0.25, 0.5\right)}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
    9. Add Preprocessing

    Alternative 3: 98.5% accurate, 0.6× speedup?

    \[\begin{array}{l} p_m = \left|p\right| \\ \begin{array}{l} t_0 := \frac{x}{\sqrt{x \cdot x + \left(p\_m \cdot 4\right) \cdot p\_m}}\\ \mathbf{if}\;t\_0 \leq -0.6:\\ \;\;\;\;\frac{-p\_m}{x}\\ \mathbf{elif}\;t\_0 \leq 4 \cdot 10^{-7}:\\ \;\;\;\;\sqrt{0.5}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
    p_m = (fabs.f64 p)
    (FPCore (p_m x)
     :precision binary64
     (let* ((t_0 (/ x (sqrt (+ (* x x) (* (* p_m 4.0) p_m))))))
       (if (<= t_0 -0.6) (/ (- p_m) x) (if (<= t_0 4e-7) (sqrt 0.5) 1.0))))
    p_m = fabs(p);
    double code(double p_m, double x) {
    	double t_0 = x / sqrt(((x * x) + ((p_m * 4.0) * p_m)));
    	double tmp;
    	if (t_0 <= -0.6) {
    		tmp = -p_m / x;
    	} else if (t_0 <= 4e-7) {
    		tmp = sqrt(0.5);
    	} else {
    		tmp = 1.0;
    	}
    	return tmp;
    }
    
    p_m = abs(p)
    real(8) function code(p_m, x)
        real(8), intent (in) :: p_m
        real(8), intent (in) :: x
        real(8) :: t_0
        real(8) :: tmp
        t_0 = x / sqrt(((x * x) + ((p_m * 4.0d0) * p_m)))
        if (t_0 <= (-0.6d0)) then
            tmp = -p_m / x
        else if (t_0 <= 4d-7) then
            tmp = sqrt(0.5d0)
        else
            tmp = 1.0d0
        end if
        code = tmp
    end function
    
    p_m = Math.abs(p);
    public static double code(double p_m, double x) {
    	double t_0 = x / Math.sqrt(((x * x) + ((p_m * 4.0) * p_m)));
    	double tmp;
    	if (t_0 <= -0.6) {
    		tmp = -p_m / x;
    	} else if (t_0 <= 4e-7) {
    		tmp = Math.sqrt(0.5);
    	} else {
    		tmp = 1.0;
    	}
    	return tmp;
    }
    
    p_m = math.fabs(p)
    def code(p_m, x):
    	t_0 = x / math.sqrt(((x * x) + ((p_m * 4.0) * p_m)))
    	tmp = 0
    	if t_0 <= -0.6:
    		tmp = -p_m / x
    	elif t_0 <= 4e-7:
    		tmp = math.sqrt(0.5)
    	else:
    		tmp = 1.0
    	return tmp
    
    p_m = abs(p)
    function code(p_m, x)
    	t_0 = Float64(x / sqrt(Float64(Float64(x * x) + Float64(Float64(p_m * 4.0) * p_m))))
    	tmp = 0.0
    	if (t_0 <= -0.6)
    		tmp = Float64(Float64(-p_m) / x);
    	elseif (t_0 <= 4e-7)
    		tmp = sqrt(0.5);
    	else
    		tmp = 1.0;
    	end
    	return tmp
    end
    
    p_m = abs(p);
    function tmp_2 = code(p_m, x)
    	t_0 = x / sqrt(((x * x) + ((p_m * 4.0) * p_m)));
    	tmp = 0.0;
    	if (t_0 <= -0.6)
    		tmp = -p_m / x;
    	elseif (t_0 <= 4e-7)
    		tmp = sqrt(0.5);
    	else
    		tmp = 1.0;
    	end
    	tmp_2 = tmp;
    end
    
    p_m = N[Abs[p], $MachinePrecision]
    code[p$95$m_, x_] := Block[{t$95$0 = N[(x / N[Sqrt[N[(N[(x * x), $MachinePrecision] + N[(N[(p$95$m * 4.0), $MachinePrecision] * p$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -0.6], N[((-p$95$m) / x), $MachinePrecision], If[LessEqual[t$95$0, 4e-7], N[Sqrt[0.5], $MachinePrecision], 1.0]]]
    
    \begin{array}{l}
    p_m = \left|p\right|
    
    \\
    \begin{array}{l}
    t_0 := \frac{x}{\sqrt{x \cdot x + \left(p\_m \cdot 4\right) \cdot p\_m}}\\
    \mathbf{if}\;t\_0 \leq -0.6:\\
    \;\;\;\;\frac{-p\_m}{x}\\
    
    \mathbf{elif}\;t\_0 \leq 4 \cdot 10^{-7}:\\
    \;\;\;\;\sqrt{0.5}\\
    
    \mathbf{else}:\\
    \;\;\;\;1\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))) < -0.599999999999999978

      1. Initial program 16.3%

        \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
      2. Add Preprocessing
      3. 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. metadata-evalN/A

          \[\leadsto \sqrt{\frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot \frac{1}{2} + \color{blue}{\frac{1}{2}}} \]
        6. lower-fma.f6416.3

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

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

          \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\color{blue}{\left(4 \cdot p\right) \cdot p} + x \cdot x}}, \frac{1}{2}, \frac{1}{2}\right)} \]
        9. lower-fma.f6416.3

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

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

          \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, \frac{1}{2}, \frac{1}{2}\right)} \]
        12. lower-*.f6416.3

          \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, 0.5, 0.5\right)} \]
      4. Applied rewrites16.3%

        \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, 0.5, 0.5\right)}} \]
      5. Taylor expanded in x around -inf

        \[\leadsto \color{blue}{-1 \cdot \frac{p}{x}} \]
      6. Step-by-step derivation
        1. associate-*r/N/A

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

          \[\leadsto \color{blue}{\frac{-1 \cdot p}{x}} \]
        3. mul-1-negN/A

          \[\leadsto \frac{\color{blue}{\mathsf{neg}\left(p\right)}}{x} \]
        4. lower-neg.f6446.9

          \[\leadsto \frac{\color{blue}{-p}}{x} \]
      7. Applied rewrites46.9%

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

      if -0.599999999999999978 < (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))) < 3.9999999999999998e-7

      1. Initial program 100.0%

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

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2}}} \]
      4. Step-by-step derivation
        1. Applied rewrites96.5%

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

        if 3.9999999999999998e-7 < (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x))))

        1. Initial program 100.0%

          \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
        2. Add Preprocessing
        3. 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. metadata-evalN/A

            \[\leadsto \sqrt{\frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot \frac{1}{2} + \color{blue}{\frac{1}{2}}} \]
          6. lower-fma.f64100.0

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

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

            \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\color{blue}{\left(4 \cdot p\right) \cdot p} + x \cdot x}}, \frac{1}{2}, \frac{1}{2}\right)} \]
          9. lower-fma.f64100.0

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

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

            \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, \frac{1}{2}, \frac{1}{2}\right)} \]
          12. lower-*.f64100.0

            \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, 0.5, 0.5\right)} \]
        4. Applied rewrites100.0%

          \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, 0.5, 0.5\right)}} \]
        5. Taylor expanded in p around 0

          \[\leadsto \color{blue}{1} \]
        6. Step-by-step derivation
          1. Applied rewrites100.0%

            \[\leadsto \color{blue}{1} \]
        7. Recombined 3 regimes into one program.
        8. Final simplification85.5%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x}{\sqrt{x \cdot x + \left(p \cdot 4\right) \cdot p}} \leq -0.6:\\ \;\;\;\;\frac{-p}{x}\\ \mathbf{elif}\;\frac{x}{\sqrt{x \cdot x + \left(p \cdot 4\right) \cdot p}} \leq 4 \cdot 10^{-7}:\\ \;\;\;\;\sqrt{0.5}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
        9. Add Preprocessing

        Alternative 4: 75.3% accurate, 1.0× speedup?

        \[\begin{array}{l} p_m = \left|p\right| \\ \begin{array}{l} \mathbf{if}\;\frac{x}{\sqrt{x \cdot x + \left(p\_m \cdot 4\right) \cdot p\_m}} \leq 0.45:\\ \;\;\;\;\sqrt{0.5}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
        p_m = (fabs.f64 p)
        (FPCore (p_m x)
         :precision binary64
         (if (<= (/ x (sqrt (+ (* x x) (* (* p_m 4.0) p_m)))) 0.45) (sqrt 0.5) 1.0))
        p_m = fabs(p);
        double code(double p_m, double x) {
        	double tmp;
        	if ((x / sqrt(((x * x) + ((p_m * 4.0) * p_m)))) <= 0.45) {
        		tmp = sqrt(0.5);
        	} else {
        		tmp = 1.0;
        	}
        	return tmp;
        }
        
        p_m = abs(p)
        real(8) function code(p_m, x)
            real(8), intent (in) :: p_m
            real(8), intent (in) :: x
            real(8) :: tmp
            if ((x / sqrt(((x * x) + ((p_m * 4.0d0) * p_m)))) <= 0.45d0) then
                tmp = sqrt(0.5d0)
            else
                tmp = 1.0d0
            end if
            code = tmp
        end function
        
        p_m = Math.abs(p);
        public static double code(double p_m, double x) {
        	double tmp;
        	if ((x / Math.sqrt(((x * x) + ((p_m * 4.0) * p_m)))) <= 0.45) {
        		tmp = Math.sqrt(0.5);
        	} else {
        		tmp = 1.0;
        	}
        	return tmp;
        }
        
        p_m = math.fabs(p)
        def code(p_m, x):
        	tmp = 0
        	if (x / math.sqrt(((x * x) + ((p_m * 4.0) * p_m)))) <= 0.45:
        		tmp = math.sqrt(0.5)
        	else:
        		tmp = 1.0
        	return tmp
        
        p_m = abs(p)
        function code(p_m, x)
        	tmp = 0.0
        	if (Float64(x / sqrt(Float64(Float64(x * x) + Float64(Float64(p_m * 4.0) * p_m)))) <= 0.45)
        		tmp = sqrt(0.5);
        	else
        		tmp = 1.0;
        	end
        	return tmp
        end
        
        p_m = abs(p);
        function tmp_2 = code(p_m, x)
        	tmp = 0.0;
        	if ((x / sqrt(((x * x) + ((p_m * 4.0) * p_m)))) <= 0.45)
        		tmp = sqrt(0.5);
        	else
        		tmp = 1.0;
        	end
        	tmp_2 = tmp;
        end
        
        p_m = N[Abs[p], $MachinePrecision]
        code[p$95$m_, x_] := If[LessEqual[N[(x / N[Sqrt[N[(N[(x * x), $MachinePrecision] + N[(N[(p$95$m * 4.0), $MachinePrecision] * p$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], 0.45], N[Sqrt[0.5], $MachinePrecision], 1.0]
        
        \begin{array}{l}
        p_m = \left|p\right|
        
        \\
        \begin{array}{l}
        \mathbf{if}\;\frac{x}{\sqrt{x \cdot x + \left(p\_m \cdot 4\right) \cdot p\_m}} \leq 0.45:\\
        \;\;\;\;\sqrt{0.5}\\
        
        \mathbf{else}:\\
        \;\;\;\;1\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x)))) < 0.450000000000000011

          1. Initial program 72.1%

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

            \[\leadsto \sqrt{\color{blue}{\frac{1}{2}}} \]
          4. Step-by-step derivation
            1. Applied rewrites66.3%

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

            if 0.450000000000000011 < (/.f64 x (sqrt.f64 (+.f64 (*.f64 (*.f64 #s(literal 4 binary64) p) p) (*.f64 x x))))

            1. Initial program 100.0%

              \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
            2. Add Preprocessing
            3. 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. metadata-evalN/A

                \[\leadsto \sqrt{\frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot \frac{1}{2} + \color{blue}{\frac{1}{2}}} \]
              6. lower-fma.f64100.0

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

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

                \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\color{blue}{\left(4 \cdot p\right) \cdot p} + x \cdot x}}, \frac{1}{2}, \frac{1}{2}\right)} \]
              9. lower-fma.f64100.0

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

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

                \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, \frac{1}{2}, \frac{1}{2}\right)} \]
              12. lower-*.f64100.0

                \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, 0.5, 0.5\right)} \]
            4. Applied rewrites100.0%

              \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, 0.5, 0.5\right)}} \]
            5. Taylor expanded in p around 0

              \[\leadsto \color{blue}{1} \]
            6. Step-by-step derivation
              1. Applied rewrites100.0%

                \[\leadsto \color{blue}{1} \]
            7. Recombined 2 regimes into one program.
            8. Final simplification75.5%

              \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x}{\sqrt{x \cdot x + \left(p \cdot 4\right) \cdot p}} \leq 0.45:\\ \;\;\;\;\sqrt{0.5}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]
            9. Add Preprocessing

            Alternative 5: 37.0% accurate, 58.0× speedup?

            \[\begin{array}{l} p_m = \left|p\right| \\ 1 \end{array} \]
            p_m = (fabs.f64 p)
            (FPCore (p_m x) :precision binary64 1.0)
            p_m = fabs(p);
            double code(double p_m, double x) {
            	return 1.0;
            }
            
            p_m = abs(p)
            real(8) function code(p_m, x)
                real(8), intent (in) :: p_m
                real(8), intent (in) :: x
                code = 1.0d0
            end function
            
            p_m = Math.abs(p);
            public static double code(double p_m, double x) {
            	return 1.0;
            }
            
            p_m = math.fabs(p)
            def code(p_m, x):
            	return 1.0
            
            p_m = abs(p)
            function code(p_m, x)
            	return 1.0
            end
            
            p_m = abs(p);
            function tmp = code(p_m, x)
            	tmp = 1.0;
            end
            
            p_m = N[Abs[p], $MachinePrecision]
            code[p$95$m_, x_] := 1.0
            
            \begin{array}{l}
            p_m = \left|p\right|
            
            \\
            1
            \end{array}
            
            Derivation
            1. Initial program 79.7%

              \[\sqrt{0.5 \cdot \left(1 + \frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}}\right)} \]
            2. Add Preprocessing
            3. 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. metadata-evalN/A

                \[\leadsto \sqrt{\frac{x}{\sqrt{\left(4 \cdot p\right) \cdot p + x \cdot x}} \cdot \frac{1}{2} + \color{blue}{\frac{1}{2}}} \]
              6. lower-fma.f6479.7

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

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

                \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\color{blue}{\left(4 \cdot p\right) \cdot p} + x \cdot x}}, \frac{1}{2}, \frac{1}{2}\right)} \]
              9. lower-fma.f6479.7

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

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

                \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, \frac{1}{2}, \frac{1}{2}\right)} \]
              12. lower-*.f6479.7

                \[\leadsto \sqrt{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(\color{blue}{p \cdot 4}, p, x \cdot x\right)}}, 0.5, 0.5\right)} \]
            4. Applied rewrites79.7%

              \[\leadsto \sqrt{\color{blue}{\mathsf{fma}\left(\frac{x}{\sqrt{\mathsf{fma}\left(p \cdot 4, p, x \cdot x\right)}}, 0.5, 0.5\right)}} \]
            5. Taylor expanded in p around 0

              \[\leadsto \color{blue}{1} \]
            6. Step-by-step derivation
              1. Applied rewrites38.4%

                \[\leadsto \color{blue}{1} \]
              2. Add Preprocessing

              Developer Target 1: 79.5% accurate, 0.2× 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 2024236 
              (FPCore (p x)
                :name "Given's Rotation SVD example"
                :precision binary64
                :pre (and (< 1e-150 (fabs x)) (< (fabs x) 1e+150))
              
                :alt
                (! :herbie-platform default (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))))))))