Migdal et al, Equation (64)

Percentage Accurate: 99.6% → 99.6%
Time: 12.9s
Alternatives: 11
Speedup: 1.9×

Specification

?
\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{\cos th}{\sqrt{2}}\\ t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2 \cdot a2\right) \end{array} \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (let* ((t_1 (/ (cos th) (sqrt 2.0))))
   (+ (* t_1 (* a1 a1)) (* t_1 (* a2 a2)))))
double code(double a1, double a2, double th) {
	double t_1 = cos(th) / sqrt(2.0);
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
}
real(8) function code(a1, a2, th)
    real(8), intent (in) :: a1
    real(8), intent (in) :: a2
    real(8), intent (in) :: th
    real(8) :: t_1
    t_1 = cos(th) / sqrt(2.0d0)
    code = (t_1 * (a1 * a1)) + (t_1 * (a2 * a2))
end function
public static double code(double a1, double a2, double th) {
	double t_1 = Math.cos(th) / Math.sqrt(2.0);
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
}
def code(a1, a2, th):
	t_1 = math.cos(th) / math.sqrt(2.0)
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2))
function code(a1, a2, th)
	t_1 = Float64(cos(th) / sqrt(2.0))
	return Float64(Float64(t_1 * Float64(a1 * a1)) + Float64(t_1 * Float64(a2 * a2)))
end
function tmp = code(a1, a2, th)
	t_1 = cos(th) / sqrt(2.0);
	tmp = (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
end
code[a1_, a2_, th_] := Block[{t$95$1 = N[(N[Cos[th], $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, N[(N[(t$95$1 * N[(a1 * a1), $MachinePrecision]), $MachinePrecision] + N[(t$95$1 * N[(a2 * a2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{\cos th}{\sqrt{2}}\\
t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2 \cdot a2\right)
\end{array}
\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 11 alternatives:

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

Initial Program: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{\cos th}{\sqrt{2}}\\ t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2 \cdot a2\right) \end{array} \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (let* ((t_1 (/ (cos th) (sqrt 2.0))))
   (+ (* t_1 (* a1 a1)) (* t_1 (* a2 a2)))))
double code(double a1, double a2, double th) {
	double t_1 = cos(th) / sqrt(2.0);
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
}
real(8) function code(a1, a2, th)
    real(8), intent (in) :: a1
    real(8), intent (in) :: a2
    real(8), intent (in) :: th
    real(8) :: t_1
    t_1 = cos(th) / sqrt(2.0d0)
    code = (t_1 * (a1 * a1)) + (t_1 * (a2 * a2))
end function
public static double code(double a1, double a2, double th) {
	double t_1 = Math.cos(th) / Math.sqrt(2.0);
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
}
def code(a1, a2, th):
	t_1 = math.cos(th) / math.sqrt(2.0)
	return (t_1 * (a1 * a1)) + (t_1 * (a2 * a2))
function code(a1, a2, th)
	t_1 = Float64(cos(th) / sqrt(2.0))
	return Float64(Float64(t_1 * Float64(a1 * a1)) + Float64(t_1 * Float64(a2 * a2)))
end
function tmp = code(a1, a2, th)
	t_1 = cos(th) / sqrt(2.0);
	tmp = (t_1 * (a1 * a1)) + (t_1 * (a2 * a2));
end
code[a1_, a2_, th_] := Block[{t$95$1 = N[(N[Cos[th], $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, N[(N[(t$95$1 * N[(a1 * a1), $MachinePrecision]), $MachinePrecision] + N[(t$95$1 * N[(a2 * a2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{\cos th}{\sqrt{2}}\\
t\_1 \cdot \left(a1 \cdot a1\right) + t\_1 \cdot \left(a2 \cdot a2\right)
\end{array}
\end{array}

Alternative 1: 99.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(\sqrt{2}, \cos th \cdot \left(a2 \cdot a2\right), \sqrt{2} \cdot \left(\cos th \cdot \left(a1 \cdot a1\right)\right)\right) \cdot 0.5 \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (*
  (fma (sqrt 2.0) (* (cos th) (* a2 a2)) (* (sqrt 2.0) (* (cos th) (* a1 a1))))
  0.5))
double code(double a1, double a2, double th) {
	return fma(sqrt(2.0), (cos(th) * (a2 * a2)), (sqrt(2.0) * (cos(th) * (a1 * a1)))) * 0.5;
}
function code(a1, a2, th)
	return Float64(fma(sqrt(2.0), Float64(cos(th) * Float64(a2 * a2)), Float64(sqrt(2.0) * Float64(cos(th) * Float64(a1 * a1)))) * 0.5)
end
code[a1_, a2_, th_] := N[(N[(N[Sqrt[2.0], $MachinePrecision] * N[(N[Cos[th], $MachinePrecision] * N[(a2 * a2), $MachinePrecision]), $MachinePrecision] + N[(N[Sqrt[2.0], $MachinePrecision] * N[(N[Cos[th], $MachinePrecision] * N[(a1 * a1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(\sqrt{2}, \cos th \cdot \left(a2 \cdot a2\right), \sqrt{2} \cdot \left(\cos th \cdot \left(a1 \cdot a1\right)\right)\right) \cdot 0.5
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. associate-*l/N/A

      \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. associate-*l/N/A

      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
    3. frac-addN/A

      \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
    4. rem-square-sqrtN/A

      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
    5. div-invN/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
    6. metadata-evalN/A

      \[\leadsto \left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \color{blue}{\frac{1}{2}} \]
    7. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
  4. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{2}, \cos th \cdot \left(a2 \cdot a2\right), \sqrt{2} \cdot \left(\cos th \cdot \left(a1 \cdot a1\right)\right)\right) \cdot 0.5} \]
  5. Add Preprocessing

Alternative 2: 74.8% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{a2}{\sqrt{2}}\\ t_2 := \frac{\cos th}{\sqrt{2}}\\ \mathbf{if}\;\left(a1 \cdot a1\right) \cdot t\_2 + \left(a2 \cdot a2\right) \cdot t\_2 \leq -1 \cdot 10^{-180}:\\ \;\;\;\;\mathsf{fma}\left(a2, t\_1, \mathsf{fma}\left(a2, a2, 0\right) \cdot \left(\left(th \cdot \frac{th}{\sqrt{2}}\right) \cdot -0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(t\_1, a2, \frac{a1 \cdot a1}{\sqrt{2}}\right)\\ \end{array} \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (let* ((t_1 (/ a2 (sqrt 2.0))) (t_2 (/ (cos th) (sqrt 2.0))))
   (if (<= (+ (* (* a1 a1) t_2) (* (* a2 a2) t_2)) -1e-180)
     (fma a2 t_1 (* (fma a2 a2 0.0) (* (* th (/ th (sqrt 2.0))) -0.5)))
     (fma t_1 a2 (/ (* a1 a1) (sqrt 2.0))))))
double code(double a1, double a2, double th) {
	double t_1 = a2 / sqrt(2.0);
	double t_2 = cos(th) / sqrt(2.0);
	double tmp;
	if ((((a1 * a1) * t_2) + ((a2 * a2) * t_2)) <= -1e-180) {
		tmp = fma(a2, t_1, (fma(a2, a2, 0.0) * ((th * (th / sqrt(2.0))) * -0.5)));
	} else {
		tmp = fma(t_1, a2, ((a1 * a1) / sqrt(2.0)));
	}
	return tmp;
}
function code(a1, a2, th)
	t_1 = Float64(a2 / sqrt(2.0))
	t_2 = Float64(cos(th) / sqrt(2.0))
	tmp = 0.0
	if (Float64(Float64(Float64(a1 * a1) * t_2) + Float64(Float64(a2 * a2) * t_2)) <= -1e-180)
		tmp = fma(a2, t_1, Float64(fma(a2, a2, 0.0) * Float64(Float64(th * Float64(th / sqrt(2.0))) * -0.5)));
	else
		tmp = fma(t_1, a2, Float64(Float64(a1 * a1) / sqrt(2.0)));
	end
	return tmp
end
code[a1_, a2_, th_] := Block[{t$95$1 = N[(a2 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[Cos[th], $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(a1 * a1), $MachinePrecision] * t$95$2), $MachinePrecision] + N[(N[(a2 * a2), $MachinePrecision] * t$95$2), $MachinePrecision]), $MachinePrecision], -1e-180], N[(a2 * t$95$1 + N[(N[(a2 * a2 + 0.0), $MachinePrecision] * N[(N[(th * N[(th / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(t$95$1 * a2 + N[(N[(a1 * a1), $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{a2}{\sqrt{2}}\\
t_2 := \frac{\cos th}{\sqrt{2}}\\
\mathbf{if}\;\left(a1 \cdot a1\right) \cdot t\_2 + \left(a2 \cdot a2\right) \cdot t\_2 \leq -1 \cdot 10^{-180}:\\
\;\;\;\;\mathsf{fma}\left(a2, t\_1, \mathsf{fma}\left(a2, a2, 0\right) \cdot \left(\left(th \cdot \frac{th}{\sqrt{2}}\right) \cdot -0.5\right)\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(t\_1, a2, \frac{a1 \cdot a1}{\sqrt{2}}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a1 a1)) (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a2 a2))) < -1e-180

    1. Initial program 99.7%

      \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. distribute-lft-outN/A

        \[\leadsto \color{blue}{\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)} \]
      2. *-commutativeN/A

        \[\leadsto \color{blue}{\left(a1 \cdot a1 + a2 \cdot a2\right) \cdot \frac{\cos th}{\sqrt{2}}} \]
      3. clear-numN/A

        \[\leadsto \left(a1 \cdot a1 + a2 \cdot a2\right) \cdot \color{blue}{\frac{1}{\frac{\sqrt{2}}{\cos th}}} \]
      4. un-div-invN/A

        \[\leadsto \color{blue}{\frac{a1 \cdot a1 + a2 \cdot a2}{\frac{\sqrt{2}}{\cos th}}} \]
      5. div-invN/A

        \[\leadsto \frac{a1 \cdot a1 + a2 \cdot a2}{\color{blue}{\sqrt{2} \cdot \frac{1}{\cos th}}} \]
      6. associate-/r*N/A

        \[\leadsto \color{blue}{\frac{\frac{a1 \cdot a1 + a2 \cdot a2}{\sqrt{2}}}{\frac{1}{\cos th}}} \]
      7. *-lft-identityN/A

        \[\leadsto \frac{\frac{\color{blue}{1 \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)}}{\sqrt{2}}}{\frac{1}{\cos th}} \]
      8. associate-*l/N/A

        \[\leadsto \frac{\color{blue}{\frac{1}{\sqrt{2}} \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)}}{\frac{1}{\cos th}} \]
      9. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{1}{\sqrt{2}} \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)}{\frac{1}{\cos th}}} \]
      10. associate-*l/N/A

        \[\leadsto \frac{\color{blue}{\frac{1 \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)}{\sqrt{2}}}}{\frac{1}{\cos th}} \]
      11. *-lft-identityN/A

        \[\leadsto \frac{\frac{\color{blue}{a1 \cdot a1 + a2 \cdot a2}}{\sqrt{2}}}{\frac{1}{\cos th}} \]
      12. /-lowering-/.f64N/A

        \[\leadsto \frac{\color{blue}{\frac{a1 \cdot a1 + a2 \cdot a2}{\sqrt{2}}}}{\frac{1}{\cos th}} \]
      13. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{\frac{\color{blue}{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}}{\sqrt{2}}}{\frac{1}{\cos th}} \]
      14. *-lowering-*.f64N/A

        \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)}{\sqrt{2}}}{\frac{1}{\cos th}} \]
      15. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\color{blue}{\sqrt{2}}}}{\frac{1}{\cos th}} \]
      16. /-lowering-/.f64N/A

        \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}}{\color{blue}{\frac{1}{\cos th}}} \]
      17. cos-lowering-cos.f6499.7

        \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}}{\frac{1}{\color{blue}{\cos th}}} \]
    4. Applied egg-rr99.7%

      \[\leadsto \color{blue}{\frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}}{\frac{1}{\cos th}}} \]
    5. Taylor expanded in th around 0

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}}{\color{blue}{1 + \frac{1}{2} \cdot {th}^{2}}} \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}}{\color{blue}{\frac{1}{2} \cdot {th}^{2} + 1}} \]
      2. *-commutativeN/A

        \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}}{\color{blue}{{th}^{2} \cdot \frac{1}{2}} + 1} \]
      3. unpow2N/A

        \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}}{\color{blue}{\left(th \cdot th\right)} \cdot \frac{1}{2} + 1} \]
      4. associate-*l*N/A

        \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}}{\color{blue}{th \cdot \left(th \cdot \frac{1}{2}\right)} + 1} \]
      5. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}}{\color{blue}{\mathsf{fma}\left(th, th \cdot \frac{1}{2}, 1\right)}} \]
      6. *-lowering-*.f640.9

        \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}}{\mathsf{fma}\left(th, \color{blue}{th \cdot 0.5}, 1\right)} \]
    7. Simplified0.9%

      \[\leadsto \frac{\frac{\mathsf{fma}\left(a1, a1, a2 \cdot a2\right)}{\sqrt{2}}}{\color{blue}{\mathsf{fma}\left(th, th \cdot 0.5, 1\right)}} \]
    8. Taylor expanded in a1 around 0

      \[\leadsto \color{blue}{\frac{{a2}^{2}}{\sqrt{2} \cdot \left(1 + \frac{1}{2} \cdot {th}^{2}\right)}} \]
    9. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{{a2}^{2}}{\sqrt{2} \cdot \left(1 + \frac{1}{2} \cdot {th}^{2}\right)}} \]
      2. unpow2N/A

        \[\leadsto \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2} \cdot \left(1 + \frac{1}{2} \cdot {th}^{2}\right)} \]
      3. *-lowering-*.f64N/A

        \[\leadsto \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2} \cdot \left(1 + \frac{1}{2} \cdot {th}^{2}\right)} \]
      4. *-lowering-*.f64N/A

        \[\leadsto \frac{a2 \cdot a2}{\color{blue}{\sqrt{2} \cdot \left(1 + \frac{1}{2} \cdot {th}^{2}\right)}} \]
      5. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \frac{a2 \cdot a2}{\color{blue}{\sqrt{2}} \cdot \left(1 + \frac{1}{2} \cdot {th}^{2}\right)} \]
      6. +-commutativeN/A

        \[\leadsto \frac{a2 \cdot a2}{\sqrt{2} \cdot \color{blue}{\left(\frac{1}{2} \cdot {th}^{2} + 1\right)}} \]
      7. accelerator-lowering-fma.f64N/A

        \[\leadsto \frac{a2 \cdot a2}{\sqrt{2} \cdot \color{blue}{\mathsf{fma}\left(\frac{1}{2}, {th}^{2}, 1\right)}} \]
      8. unpow2N/A

        \[\leadsto \frac{a2 \cdot a2}{\sqrt{2} \cdot \mathsf{fma}\left(\frac{1}{2}, \color{blue}{th \cdot th}, 1\right)} \]
      9. *-lowering-*.f641.4

        \[\leadsto \frac{a2 \cdot a2}{\sqrt{2} \cdot \mathsf{fma}\left(0.5, \color{blue}{th \cdot th}, 1\right)} \]
    10. Simplified1.4%

      \[\leadsto \color{blue}{\frac{a2 \cdot a2}{\sqrt{2} \cdot \mathsf{fma}\left(0.5, th \cdot th, 1\right)}} \]
    11. Taylor expanded in th around 0

      \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{{a2}^{2} \cdot {th}^{2}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}}} \]
    12. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\frac{{a2}^{2}}{\sqrt{2}} + \frac{-1}{2} \cdot \frac{{a2}^{2} \cdot {th}^{2}}{\sqrt{2}}} \]
      2. unpow2N/A

        \[\leadsto \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}} + \frac{-1}{2} \cdot \frac{{a2}^{2} \cdot {th}^{2}}{\sqrt{2}} \]
      3. associate-/l*N/A

        \[\leadsto \color{blue}{a2 \cdot \frac{a2}{\sqrt{2}}} + \frac{-1}{2} \cdot \frac{{a2}^{2} \cdot {th}^{2}}{\sqrt{2}} \]
      4. accelerator-lowering-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \frac{-1}{2} \cdot \frac{{a2}^{2} \cdot {th}^{2}}{\sqrt{2}}\right)} \]
      5. /-lowering-/.f64N/A

        \[\leadsto \mathsf{fma}\left(a2, \color{blue}{\frac{a2}{\sqrt{2}}}, \frac{-1}{2} \cdot \frac{{a2}^{2} \cdot {th}^{2}}{\sqrt{2}}\right) \]
      6. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\color{blue}{\sqrt{2}}}, \frac{-1}{2} \cdot \frac{{a2}^{2} \cdot {th}^{2}}{\sqrt{2}}\right) \]
      7. *-commutativeN/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \color{blue}{\frac{{a2}^{2} \cdot {th}^{2}}{\sqrt{2}} \cdot \frac{-1}{2}}\right) \]
      8. associate-/l*N/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \color{blue}{\left({a2}^{2} \cdot \frac{{th}^{2}}{\sqrt{2}}\right)} \cdot \frac{-1}{2}\right) \]
      9. associate-*l*N/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \color{blue}{{a2}^{2} \cdot \left(\frac{{th}^{2}}{\sqrt{2}} \cdot \frac{-1}{2}\right)}\right) \]
      10. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \color{blue}{{a2}^{2} \cdot \left(\frac{{th}^{2}}{\sqrt{2}} \cdot \frac{-1}{2}\right)}\right) \]
      11. +-rgt-identityN/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \color{blue}{\left({a2}^{2} + 0\right)} \cdot \left(\frac{{th}^{2}}{\sqrt{2}} \cdot \frac{-1}{2}\right)\right) \]
      12. unpow2N/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \left(\color{blue}{a2 \cdot a2} + 0\right) \cdot \left(\frac{{th}^{2}}{\sqrt{2}} \cdot \frac{-1}{2}\right)\right) \]
      13. accelerator-lowering-fma.f64N/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \color{blue}{\mathsf{fma}\left(a2, a2, 0\right)} \cdot \left(\frac{{th}^{2}}{\sqrt{2}} \cdot \frac{-1}{2}\right)\right) \]
      14. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \mathsf{fma}\left(a2, a2, 0\right) \cdot \color{blue}{\left(\frac{{th}^{2}}{\sqrt{2}} \cdot \frac{-1}{2}\right)}\right) \]
      15. unpow2N/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \mathsf{fma}\left(a2, a2, 0\right) \cdot \left(\frac{\color{blue}{th \cdot th}}{\sqrt{2}} \cdot \frac{-1}{2}\right)\right) \]
      16. associate-/l*N/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \mathsf{fma}\left(a2, a2, 0\right) \cdot \left(\color{blue}{\left(th \cdot \frac{th}{\sqrt{2}}\right)} \cdot \frac{-1}{2}\right)\right) \]
      17. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \mathsf{fma}\left(a2, a2, 0\right) \cdot \left(\color{blue}{\left(th \cdot \frac{th}{\sqrt{2}}\right)} \cdot \frac{-1}{2}\right)\right) \]
      18. /-lowering-/.f64N/A

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \mathsf{fma}\left(a2, a2, 0\right) \cdot \left(\left(th \cdot \color{blue}{\frac{th}{\sqrt{2}}}\right) \cdot \frac{-1}{2}\right)\right) \]
      19. sqrt-lowering-sqrt.f6439.8

        \[\leadsto \mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \mathsf{fma}\left(a2, a2, 0\right) \cdot \left(\left(th \cdot \frac{th}{\color{blue}{\sqrt{2}}}\right) \cdot -0.5\right)\right) \]
    13. Simplified39.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \mathsf{fma}\left(a2, a2, 0\right) \cdot \left(\left(th \cdot \frac{th}{\sqrt{2}}\right) \cdot -0.5\right)\right)} \]

    if -1e-180 < (+.f64 (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a1 a1)) (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a2 a2)))

    1. Initial program 99.5%

      \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. Add Preprocessing
    3. Taylor expanded in th around 0

      \[\leadsto \color{blue}{\frac{{a1}^{2}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}}} \]
    4. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto \frac{\color{blue}{a1 \cdot a1}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}} \]
      2. associate-/l*N/A

        \[\leadsto \color{blue}{a1 \cdot \frac{a1}{\sqrt{2}}} + \frac{{a2}^{2}}{\sqrt{2}} \]
      3. accelerator-lowering-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{{a2}^{2}}{\sqrt{2}}\right)} \]
      4. /-lowering-/.f64N/A

        \[\leadsto \mathsf{fma}\left(a1, \color{blue}{\frac{a1}{\sqrt{2}}}, \frac{{a2}^{2}}{\sqrt{2}}\right) \]
      5. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\color{blue}{\sqrt{2}}}, \frac{{a2}^{2}}{\sqrt{2}}\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \color{blue}{\frac{{a2}^{2}}{\sqrt{2}}}\right) \]
      7. unpow2N/A

        \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}}\right) \]
      8. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}}\right) \]
      9. sqrt-lowering-sqrt.f6483.8

        \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{a2 \cdot a2}{\color{blue}{\sqrt{2}}}\right) \]
    5. Simplified83.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{a2 \cdot a2}{\sqrt{2}}\right)} \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\frac{a2 \cdot a2}{\sqrt{2}} + a1 \cdot \frac{a1}{\sqrt{2}}} \]
      2. associate-/l*N/A

        \[\leadsto \color{blue}{a2 \cdot \frac{a2}{\sqrt{2}}} + a1 \cdot \frac{a1}{\sqrt{2}} \]
      3. *-commutativeN/A

        \[\leadsto \color{blue}{\frac{a2}{\sqrt{2}} \cdot a2} + a1 \cdot \frac{a1}{\sqrt{2}} \]
      4. accelerator-lowering-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, a1 \cdot \frac{a1}{\sqrt{2}}\right)} \]
      5. /-lowering-/.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{a2}{\sqrt{2}}}, a2, a1 \cdot \frac{a1}{\sqrt{2}}\right) \]
      6. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{a2}{\color{blue}{\sqrt{2}}}, a2, a1 \cdot \frac{a1}{\sqrt{2}}\right) \]
      7. associate-*r/N/A

        \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \color{blue}{\frac{a1 \cdot a1}{\sqrt{2}}}\right) \]
      8. /-lowering-/.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \color{blue}{\frac{a1 \cdot a1}{\sqrt{2}}}\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{\color{blue}{a1 \cdot a1}}{\sqrt{2}}\right) \]
      10. sqrt-lowering-sqrt.f6483.8

        \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1 \cdot a1}{\color{blue}{\sqrt{2}}}\right) \]
    7. Applied egg-rr83.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1 \cdot a1}{\sqrt{2}}\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification74.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(a1 \cdot a1\right) \cdot \frac{\cos th}{\sqrt{2}} + \left(a2 \cdot a2\right) \cdot \frac{\cos th}{\sqrt{2}} \leq -1 \cdot 10^{-180}:\\ \;\;\;\;\mathsf{fma}\left(a2, \frac{a2}{\sqrt{2}}, \mathsf{fma}\left(a2, a2, 0\right) \cdot \left(\left(th \cdot \frac{th}{\sqrt{2}}\right) \cdot -0.5\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1 \cdot a1}{\sqrt{2}}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 77.9% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{\cos th}{\sqrt{2}}\\ \mathbf{if}\;\left(a1 \cdot a1\right) \cdot t\_1 + \left(a2 \cdot a2\right) \cdot t\_1 \leq -1 \cdot 10^{-180}:\\ \;\;\;\;\left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \mathsf{fma}\left(-0.25, th \cdot th, 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1 \cdot a1}{\sqrt{2}}\right)\\ \end{array} \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (let* ((t_1 (/ (cos th) (sqrt 2.0))))
   (if (<= (+ (* (* a1 a1) t_1) (* (* a2 a2) t_1)) -1e-180)
     (* (* (sqrt 2.0) (fma a1 a1 (* a2 a2))) (fma -0.25 (* th th) 0.5))
     (fma (/ a2 (sqrt 2.0)) a2 (/ (* a1 a1) (sqrt 2.0))))))
double code(double a1, double a2, double th) {
	double t_1 = cos(th) / sqrt(2.0);
	double tmp;
	if ((((a1 * a1) * t_1) + ((a2 * a2) * t_1)) <= -1e-180) {
		tmp = (sqrt(2.0) * fma(a1, a1, (a2 * a2))) * fma(-0.25, (th * th), 0.5);
	} else {
		tmp = fma((a2 / sqrt(2.0)), a2, ((a1 * a1) / sqrt(2.0)));
	}
	return tmp;
}
function code(a1, a2, th)
	t_1 = Float64(cos(th) / sqrt(2.0))
	tmp = 0.0
	if (Float64(Float64(Float64(a1 * a1) * t_1) + Float64(Float64(a2 * a2) * t_1)) <= -1e-180)
		tmp = Float64(Float64(sqrt(2.0) * fma(a1, a1, Float64(a2 * a2))) * fma(-0.25, Float64(th * th), 0.5));
	else
		tmp = fma(Float64(a2 / sqrt(2.0)), a2, Float64(Float64(a1 * a1) / sqrt(2.0)));
	end
	return tmp
end
code[a1_, a2_, th_] := Block[{t$95$1 = N[(N[Cos[th], $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(a1 * a1), $MachinePrecision] * t$95$1), $MachinePrecision] + N[(N[(a2 * a2), $MachinePrecision] * t$95$1), $MachinePrecision]), $MachinePrecision], -1e-180], N[(N[(N[Sqrt[2.0], $MachinePrecision] * N[(a1 * a1 + N[(a2 * a2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(-0.25 * N[(th * th), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision], N[(N[(a2 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * a2 + N[(N[(a1 * a1), $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{\cos th}{\sqrt{2}}\\
\mathbf{if}\;\left(a1 \cdot a1\right) \cdot t\_1 + \left(a2 \cdot a2\right) \cdot t\_1 \leq -1 \cdot 10^{-180}:\\
\;\;\;\;\left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \mathsf{fma}\left(-0.25, th \cdot th, 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1 \cdot a1}{\sqrt{2}}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a1 a1)) (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a2 a2))) < -1e-180

    1. Initial program 99.7%

      \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. associate-*l/N/A

        \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
      2. associate-*l/N/A

        \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
      3. frac-addN/A

        \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
      4. rem-square-sqrtN/A

        \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
      5. div-invN/A

        \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
      6. metadata-evalN/A

        \[\leadsto \left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \color{blue}{\frac{1}{2}} \]
      7. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
    4. Applied egg-rr99.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{2}, \cos th \cdot \left(a2 \cdot a2\right), \sqrt{2} \cdot \left(\cos th \cdot \left(a1 \cdot a1\right)\right)\right) \cdot 0.5} \]
    5. Step-by-step derivation
      1. distribute-lft-outN/A

        \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right)\right)} \cdot \frac{1}{2} \]
      2. *-commutativeN/A

        \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot \frac{1}{2} \]
      3. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot \frac{1}{2} \]
      4. distribute-lft-outN/A

        \[\leadsto \left(\color{blue}{\left(\cos th \cdot \left(a2 \cdot a2 + a1 \cdot a1\right)\right)} \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      5. +-commutativeN/A

        \[\leadsto \left(\left(\cos th \cdot \color{blue}{\left(a1 \cdot a1 + a2 \cdot a2\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      6. *-lowering-*.f64N/A

        \[\leadsto \left(\color{blue}{\left(\cos th \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)\right)} \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      7. cos-lowering-cos.f64N/A

        \[\leadsto \left(\left(\color{blue}{\cos th} \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      8. +-commutativeN/A

        \[\leadsto \left(\left(\cos th \cdot \color{blue}{\left(a2 \cdot a2 + a1 \cdot a1\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      9. accelerator-lowering-fma.f64N/A

        \[\leadsto \left(\left(\cos th \cdot \color{blue}{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      10. *-lowering-*.f64N/A

        \[\leadsto \left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, \color{blue}{a1 \cdot a1}\right)\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      11. sqrt-lowering-sqrt.f6499.7

        \[\leadsto \left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right) \cdot \color{blue}{\sqrt{2}}\right) \cdot 0.5 \]
    6. Applied egg-rr99.7%

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot 0.5 \]
    7. Taylor expanded in th around 0

      \[\leadsto \color{blue}{\frac{-1}{4} \cdot \left({th}^{2} \cdot \left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)\right) + \frac{1}{2} \cdot \left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \]
    8. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\frac{-1}{4} \cdot {th}^{2}\right) \cdot \left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} + \frac{1}{2} \cdot \left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \]
      2. distribute-rgt-outN/A

        \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right)} \]
      3. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right)} \]
      4. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      5. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \left(\color{blue}{\sqrt{2}} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      6. unpow2N/A

        \[\leadsto \left(\sqrt{2} \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      7. accelerator-lowering-fma.f64N/A

        \[\leadsto \left(\sqrt{2} \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)}\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      8. unpow2N/A

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      10. accelerator-lowering-fma.f64N/A

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \color{blue}{\mathsf{fma}\left(\frac{-1}{4}, {th}^{2}, \frac{1}{2}\right)} \]
      11. unpow2N/A

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \mathsf{fma}\left(\frac{-1}{4}, \color{blue}{th \cdot th}, \frac{1}{2}\right) \]
      12. *-lowering-*.f6458.0

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \mathsf{fma}\left(-0.25, \color{blue}{th \cdot th}, 0.5\right) \]
    9. Simplified58.0%

      \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \mathsf{fma}\left(-0.25, th \cdot th, 0.5\right)} \]

    if -1e-180 < (+.f64 (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a1 a1)) (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a2 a2)))

    1. Initial program 99.5%

      \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. Add Preprocessing
    3. Taylor expanded in th around 0

      \[\leadsto \color{blue}{\frac{{a1}^{2}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}}} \]
    4. Step-by-step derivation
      1. unpow2N/A

        \[\leadsto \frac{\color{blue}{a1 \cdot a1}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}} \]
      2. associate-/l*N/A

        \[\leadsto \color{blue}{a1 \cdot \frac{a1}{\sqrt{2}}} + \frac{{a2}^{2}}{\sqrt{2}} \]
      3. accelerator-lowering-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{{a2}^{2}}{\sqrt{2}}\right)} \]
      4. /-lowering-/.f64N/A

        \[\leadsto \mathsf{fma}\left(a1, \color{blue}{\frac{a1}{\sqrt{2}}}, \frac{{a2}^{2}}{\sqrt{2}}\right) \]
      5. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\color{blue}{\sqrt{2}}}, \frac{{a2}^{2}}{\sqrt{2}}\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \color{blue}{\frac{{a2}^{2}}{\sqrt{2}}}\right) \]
      7. unpow2N/A

        \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}}\right) \]
      8. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}}\right) \]
      9. sqrt-lowering-sqrt.f6483.8

        \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{a2 \cdot a2}{\color{blue}{\sqrt{2}}}\right) \]
    5. Simplified83.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{a2 \cdot a2}{\sqrt{2}}\right)} \]
    6. Step-by-step derivation
      1. +-commutativeN/A

        \[\leadsto \color{blue}{\frac{a2 \cdot a2}{\sqrt{2}} + a1 \cdot \frac{a1}{\sqrt{2}}} \]
      2. associate-/l*N/A

        \[\leadsto \color{blue}{a2 \cdot \frac{a2}{\sqrt{2}}} + a1 \cdot \frac{a1}{\sqrt{2}} \]
      3. *-commutativeN/A

        \[\leadsto \color{blue}{\frac{a2}{\sqrt{2}} \cdot a2} + a1 \cdot \frac{a1}{\sqrt{2}} \]
      4. accelerator-lowering-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, a1 \cdot \frac{a1}{\sqrt{2}}\right)} \]
      5. /-lowering-/.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{a2}{\sqrt{2}}}, a2, a1 \cdot \frac{a1}{\sqrt{2}}\right) \]
      6. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{a2}{\color{blue}{\sqrt{2}}}, a2, a1 \cdot \frac{a1}{\sqrt{2}}\right) \]
      7. associate-*r/N/A

        \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \color{blue}{\frac{a1 \cdot a1}{\sqrt{2}}}\right) \]
      8. /-lowering-/.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \color{blue}{\frac{a1 \cdot a1}{\sqrt{2}}}\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{\color{blue}{a1 \cdot a1}}{\sqrt{2}}\right) \]
      10. sqrt-lowering-sqrt.f6483.8

        \[\leadsto \mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1 \cdot a1}{\color{blue}{\sqrt{2}}}\right) \]
    7. Applied egg-rr83.8%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1 \cdot a1}{\sqrt{2}}\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification78.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(a1 \cdot a1\right) \cdot \frac{\cos th}{\sqrt{2}} + \left(a2 \cdot a2\right) \cdot \frac{\cos th}{\sqrt{2}} \leq -1 \cdot 10^{-180}:\\ \;\;\;\;\left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \mathsf{fma}\left(-0.25, th \cdot th, 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\mathsf{fma}\left(\frac{a2}{\sqrt{2}}, a2, \frac{a1 \cdot a1}{\sqrt{2}}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 77.9% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\\ t_2 := \frac{\cos th}{\sqrt{2}}\\ \mathbf{if}\;\left(a1 \cdot a1\right) \cdot t\_2 + \left(a2 \cdot a2\right) \cdot t\_2 \leq -1 \cdot 10^{-180}:\\ \;\;\;\;t\_1 \cdot \mathsf{fma}\left(-0.25, th \cdot th, 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot t\_1\\ \end{array} \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (let* ((t_1 (* (sqrt 2.0) (fma a1 a1 (* a2 a2))))
        (t_2 (/ (cos th) (sqrt 2.0))))
   (if (<= (+ (* (* a1 a1) t_2) (* (* a2 a2) t_2)) -1e-180)
     (* t_1 (fma -0.25 (* th th) 0.5))
     (* 0.5 t_1))))
double code(double a1, double a2, double th) {
	double t_1 = sqrt(2.0) * fma(a1, a1, (a2 * a2));
	double t_2 = cos(th) / sqrt(2.0);
	double tmp;
	if ((((a1 * a1) * t_2) + ((a2 * a2) * t_2)) <= -1e-180) {
		tmp = t_1 * fma(-0.25, (th * th), 0.5);
	} else {
		tmp = 0.5 * t_1;
	}
	return tmp;
}
function code(a1, a2, th)
	t_1 = Float64(sqrt(2.0) * fma(a1, a1, Float64(a2 * a2)))
	t_2 = Float64(cos(th) / sqrt(2.0))
	tmp = 0.0
	if (Float64(Float64(Float64(a1 * a1) * t_2) + Float64(Float64(a2 * a2) * t_2)) <= -1e-180)
		tmp = Float64(t_1 * fma(-0.25, Float64(th * th), 0.5));
	else
		tmp = Float64(0.5 * t_1);
	end
	return tmp
end
code[a1_, a2_, th_] := Block[{t$95$1 = N[(N[Sqrt[2.0], $MachinePrecision] * N[(a1 * a1 + N[(a2 * a2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$2 = N[(N[Cos[th], $MachinePrecision] / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(N[(a1 * a1), $MachinePrecision] * t$95$2), $MachinePrecision] + N[(N[(a2 * a2), $MachinePrecision] * t$95$2), $MachinePrecision]), $MachinePrecision], -1e-180], N[(t$95$1 * N[(-0.25 * N[(th * th), $MachinePrecision] + 0.5), $MachinePrecision]), $MachinePrecision], N[(0.5 * t$95$1), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\\
t_2 := \frac{\cos th}{\sqrt{2}}\\
\mathbf{if}\;\left(a1 \cdot a1\right) \cdot t\_2 + \left(a2 \cdot a2\right) \cdot t\_2 \leq -1 \cdot 10^{-180}:\\
\;\;\;\;t\_1 \cdot \mathsf{fma}\left(-0.25, th \cdot th, 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;0.5 \cdot t\_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a1 a1)) (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a2 a2))) < -1e-180

    1. Initial program 99.7%

      \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. associate-*l/N/A

        \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
      2. associate-*l/N/A

        \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
      3. frac-addN/A

        \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
      4. rem-square-sqrtN/A

        \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
      5. div-invN/A

        \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
      6. metadata-evalN/A

        \[\leadsto \left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \color{blue}{\frac{1}{2}} \]
      7. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
    4. Applied egg-rr99.7%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{2}, \cos th \cdot \left(a2 \cdot a2\right), \sqrt{2} \cdot \left(\cos th \cdot \left(a1 \cdot a1\right)\right)\right) \cdot 0.5} \]
    5. Step-by-step derivation
      1. distribute-lft-outN/A

        \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right)\right)} \cdot \frac{1}{2} \]
      2. *-commutativeN/A

        \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot \frac{1}{2} \]
      3. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot \frac{1}{2} \]
      4. distribute-lft-outN/A

        \[\leadsto \left(\color{blue}{\left(\cos th \cdot \left(a2 \cdot a2 + a1 \cdot a1\right)\right)} \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      5. +-commutativeN/A

        \[\leadsto \left(\left(\cos th \cdot \color{blue}{\left(a1 \cdot a1 + a2 \cdot a2\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      6. *-lowering-*.f64N/A

        \[\leadsto \left(\color{blue}{\left(\cos th \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)\right)} \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      7. cos-lowering-cos.f64N/A

        \[\leadsto \left(\left(\color{blue}{\cos th} \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      8. +-commutativeN/A

        \[\leadsto \left(\left(\cos th \cdot \color{blue}{\left(a2 \cdot a2 + a1 \cdot a1\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      9. accelerator-lowering-fma.f64N/A

        \[\leadsto \left(\left(\cos th \cdot \color{blue}{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      10. *-lowering-*.f64N/A

        \[\leadsto \left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, \color{blue}{a1 \cdot a1}\right)\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
      11. sqrt-lowering-sqrt.f6499.7

        \[\leadsto \left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right) \cdot \color{blue}{\sqrt{2}}\right) \cdot 0.5 \]
    6. Applied egg-rr99.7%

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot 0.5 \]
    7. Taylor expanded in th around 0

      \[\leadsto \color{blue}{\frac{-1}{4} \cdot \left({th}^{2} \cdot \left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)\right) + \frac{1}{2} \cdot \left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \]
    8. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \color{blue}{\left(\frac{-1}{4} \cdot {th}^{2}\right) \cdot \left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} + \frac{1}{2} \cdot \left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \]
      2. distribute-rgt-outN/A

        \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right)} \]
      3. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right)} \]
      4. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      5. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \left(\color{blue}{\sqrt{2}} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      6. unpow2N/A

        \[\leadsto \left(\sqrt{2} \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      7. accelerator-lowering-fma.f64N/A

        \[\leadsto \left(\sqrt{2} \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)}\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      8. unpow2N/A

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      9. *-lowering-*.f64N/A

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \left(\frac{-1}{4} \cdot {th}^{2} + \frac{1}{2}\right) \]
      10. accelerator-lowering-fma.f64N/A

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \color{blue}{\mathsf{fma}\left(\frac{-1}{4}, {th}^{2}, \frac{1}{2}\right)} \]
      11. unpow2N/A

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \mathsf{fma}\left(\frac{-1}{4}, \color{blue}{th \cdot th}, \frac{1}{2}\right) \]
      12. *-lowering-*.f6458.0

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \mathsf{fma}\left(-0.25, \color{blue}{th \cdot th}, 0.5\right) \]
    9. Simplified58.0%

      \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \mathsf{fma}\left(-0.25, th \cdot th, 0.5\right)} \]

    if -1e-180 < (+.f64 (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a1 a1)) (*.f64 (/.f64 (cos.f64 th) (sqrt.f64 #s(literal 2 binary64))) (*.f64 a2 a2)))

    1. Initial program 99.5%

      \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. associate-*l/N/A

        \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
      2. associate-*l/N/A

        \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
      3. frac-addN/A

        \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
      4. rem-square-sqrtN/A

        \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
      5. div-invN/A

        \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
      6. metadata-evalN/A

        \[\leadsto \left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \color{blue}{\frac{1}{2}} \]
      7. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
    4. Applied egg-rr99.6%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{2}, \cos th \cdot \left(a2 \cdot a2\right), \sqrt{2} \cdot \left(\cos th \cdot \left(a1 \cdot a1\right)\right)\right) \cdot 0.5} \]
    5. Taylor expanded in th around 0

      \[\leadsto \color{blue}{\left({a1}^{2} \cdot \sqrt{2} + {a2}^{2} \cdot \sqrt{2}\right)} \cdot \frac{1}{2} \]
    6. Step-by-step derivation
      1. distribute-rgt-outN/A

        \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \cdot \frac{1}{2} \]
      2. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \cdot \frac{1}{2} \]
      3. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \left(\color{blue}{\sqrt{2}} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \frac{1}{2} \]
      4. unpow2N/A

        \[\leadsto \left(\sqrt{2} \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right)\right) \cdot \frac{1}{2} \]
      5. accelerator-lowering-fma.f64N/A

        \[\leadsto \left(\sqrt{2} \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)}\right) \cdot \frac{1}{2} \]
      6. unpow2N/A

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \frac{1}{2} \]
      7. *-lowering-*.f6483.8

        \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot 0.5 \]
    7. Simplified83.8%

      \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right)} \cdot 0.5 \]
  3. Recombined 2 regimes into one program.
  4. Final simplification78.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(a1 \cdot a1\right) \cdot \frac{\cos th}{\sqrt{2}} + \left(a2 \cdot a2\right) \cdot \frac{\cos th}{\sqrt{2}} \leq -1 \cdot 10^{-180}:\\ \;\;\;\;\left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \cdot \mathsf{fma}\left(-0.25, th \cdot th, 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;0.5 \cdot \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 99.6% accurate, 1.9× speedup?

\[\begin{array}{l} \\ 0.5 \cdot \left(\sqrt{2} \cdot \left(\cos th \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right)\right) \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (* 0.5 (* (sqrt 2.0) (* (cos th) (fma a2 a2 (* a1 a1))))))
double code(double a1, double a2, double th) {
	return 0.5 * (sqrt(2.0) * (cos(th) * fma(a2, a2, (a1 * a1))));
}
function code(a1, a2, th)
	return Float64(0.5 * Float64(sqrt(2.0) * Float64(cos(th) * fma(a2, a2, Float64(a1 * a1)))))
end
code[a1_, a2_, th_] := N[(0.5 * N[(N[Sqrt[2.0], $MachinePrecision] * N[(N[Cos[th], $MachinePrecision] * N[(a2 * a2 + N[(a1 * a1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
0.5 \cdot \left(\sqrt{2} \cdot \left(\cos th \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right)\right)
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. associate-*l/N/A

      \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. associate-*l/N/A

      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
    3. frac-addN/A

      \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
    4. rem-square-sqrtN/A

      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
    5. div-invN/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
    6. metadata-evalN/A

      \[\leadsto \left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \color{blue}{\frac{1}{2}} \]
    7. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
  4. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{2}, \cos th \cdot \left(a2 \cdot a2\right), \sqrt{2} \cdot \left(\cos th \cdot \left(a1 \cdot a1\right)\right)\right) \cdot 0.5} \]
  5. Step-by-step derivation
    1. distribute-lft-outN/A

      \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right)\right)} \cdot \frac{1}{2} \]
    2. *-commutativeN/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot \frac{1}{2} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot \frac{1}{2} \]
    4. distribute-lft-outN/A

      \[\leadsto \left(\color{blue}{\left(\cos th \cdot \left(a2 \cdot a2 + a1 \cdot a1\right)\right)} \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    5. +-commutativeN/A

      \[\leadsto \left(\left(\cos th \cdot \color{blue}{\left(a1 \cdot a1 + a2 \cdot a2\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    6. *-lowering-*.f64N/A

      \[\leadsto \left(\color{blue}{\left(\cos th \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)\right)} \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    7. cos-lowering-cos.f64N/A

      \[\leadsto \left(\left(\color{blue}{\cos th} \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    8. +-commutativeN/A

      \[\leadsto \left(\left(\cos th \cdot \color{blue}{\left(a2 \cdot a2 + a1 \cdot a1\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    9. accelerator-lowering-fma.f64N/A

      \[\leadsto \left(\left(\cos th \cdot \color{blue}{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    10. *-lowering-*.f64N/A

      \[\leadsto \left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, \color{blue}{a1 \cdot a1}\right)\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    11. sqrt-lowering-sqrt.f6499.6

      \[\leadsto \left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right) \cdot \color{blue}{\sqrt{2}}\right) \cdot 0.5 \]
  6. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot 0.5 \]
  7. Final simplification99.6%

    \[\leadsto 0.5 \cdot \left(\sqrt{2} \cdot \left(\cos th \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right)\right) \]
  8. Add Preprocessing

Alternative 6: 56.9% accurate, 2.0× speedup?

\[\begin{array}{l} \\ 0.5 \cdot \left(\sqrt{2} \cdot \left(a2 \cdot \left(\cos th \cdot a2\right)\right)\right) \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (* 0.5 (* (sqrt 2.0) (* a2 (* (cos th) a2)))))
double code(double a1, double a2, double th) {
	return 0.5 * (sqrt(2.0) * (a2 * (cos(th) * a2)));
}
real(8) function code(a1, a2, th)
    real(8), intent (in) :: a1
    real(8), intent (in) :: a2
    real(8), intent (in) :: th
    code = 0.5d0 * (sqrt(2.0d0) * (a2 * (cos(th) * a2)))
end function
public static double code(double a1, double a2, double th) {
	return 0.5 * (Math.sqrt(2.0) * (a2 * (Math.cos(th) * a2)));
}
def code(a1, a2, th):
	return 0.5 * (math.sqrt(2.0) * (a2 * (math.cos(th) * a2)))
function code(a1, a2, th)
	return Float64(0.5 * Float64(sqrt(2.0) * Float64(a2 * Float64(cos(th) * a2))))
end
function tmp = code(a1, a2, th)
	tmp = 0.5 * (sqrt(2.0) * (a2 * (cos(th) * a2)));
end
code[a1_, a2_, th_] := N[(0.5 * N[(N[Sqrt[2.0], $MachinePrecision] * N[(a2 * N[(N[Cos[th], $MachinePrecision] * a2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
0.5 \cdot \left(\sqrt{2} \cdot \left(a2 \cdot \left(\cos th \cdot a2\right)\right)\right)
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. associate-*l/N/A

      \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. associate-*l/N/A

      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
    3. frac-addN/A

      \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
    4. rem-square-sqrtN/A

      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
    5. div-invN/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
    6. metadata-evalN/A

      \[\leadsto \left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \color{blue}{\frac{1}{2}} \]
    7. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
  4. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{2}, \cos th \cdot \left(a2 \cdot a2\right), \sqrt{2} \cdot \left(\cos th \cdot \left(a1 \cdot a1\right)\right)\right) \cdot 0.5} \]
  5. Step-by-step derivation
    1. distribute-lft-outN/A

      \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right)\right)} \cdot \frac{1}{2} \]
    2. *-commutativeN/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot \frac{1}{2} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a2 \cdot a2\right) + \cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot \frac{1}{2} \]
    4. distribute-lft-outN/A

      \[\leadsto \left(\color{blue}{\left(\cos th \cdot \left(a2 \cdot a2 + a1 \cdot a1\right)\right)} \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    5. +-commutativeN/A

      \[\leadsto \left(\left(\cos th \cdot \color{blue}{\left(a1 \cdot a1 + a2 \cdot a2\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    6. *-lowering-*.f64N/A

      \[\leadsto \left(\color{blue}{\left(\cos th \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)\right)} \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    7. cos-lowering-cos.f64N/A

      \[\leadsto \left(\left(\color{blue}{\cos th} \cdot \left(a1 \cdot a1 + a2 \cdot a2\right)\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    8. +-commutativeN/A

      \[\leadsto \left(\left(\cos th \cdot \color{blue}{\left(a2 \cdot a2 + a1 \cdot a1\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    9. accelerator-lowering-fma.f64N/A

      \[\leadsto \left(\left(\cos th \cdot \color{blue}{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    10. *-lowering-*.f64N/A

      \[\leadsto \left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, \color{blue}{a1 \cdot a1}\right)\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    11. sqrt-lowering-sqrt.f6499.6

      \[\leadsto \left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right) \cdot \color{blue}{\sqrt{2}}\right) \cdot 0.5 \]
  6. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\left(\left(\cos th \cdot \mathsf{fma}\left(a2, a2, a1 \cdot a1\right)\right) \cdot \sqrt{2}\right)} \cdot 0.5 \]
  7. Taylor expanded in a2 around inf

    \[\leadsto \left(\color{blue}{\left({a2}^{2} \cdot \cos th\right)} \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
  8. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \left(\left(\color{blue}{\left(a2 \cdot a2\right)} \cdot \cos th\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    2. associate-*l*N/A

      \[\leadsto \left(\color{blue}{\left(a2 \cdot \left(a2 \cdot \cos th\right)\right)} \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \left(\color{blue}{\left(a2 \cdot \left(a2 \cdot \cos th\right)\right)} \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \left(\left(a2 \cdot \color{blue}{\left(a2 \cdot \cos th\right)}\right) \cdot \sqrt{2}\right) \cdot \frac{1}{2} \]
    5. cos-lowering-cos.f6456.4

      \[\leadsto \left(\left(a2 \cdot \left(a2 \cdot \color{blue}{\cos th}\right)\right) \cdot \sqrt{2}\right) \cdot 0.5 \]
  9. Simplified56.4%

    \[\leadsto \left(\color{blue}{\left(a2 \cdot \left(a2 \cdot \cos th\right)\right)} \cdot \sqrt{2}\right) \cdot 0.5 \]
  10. Final simplification56.4%

    \[\leadsto 0.5 \cdot \left(\sqrt{2} \cdot \left(a2 \cdot \left(\cos th \cdot a2\right)\right)\right) \]
  11. Add Preprocessing

Alternative 7: 56.9% accurate, 2.0× speedup?

\[\begin{array}{l} \\ 0.5 \cdot \left(\left(a2 \cdot a2\right) \cdot \left(\sqrt{2} \cdot \cos th\right)\right) \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (* 0.5 (* (* a2 a2) (* (sqrt 2.0) (cos th)))))
double code(double a1, double a2, double th) {
	return 0.5 * ((a2 * a2) * (sqrt(2.0) * cos(th)));
}
real(8) function code(a1, a2, th)
    real(8), intent (in) :: a1
    real(8), intent (in) :: a2
    real(8), intent (in) :: th
    code = 0.5d0 * ((a2 * a2) * (sqrt(2.0d0) * cos(th)))
end function
public static double code(double a1, double a2, double th) {
	return 0.5 * ((a2 * a2) * (Math.sqrt(2.0) * Math.cos(th)));
}
def code(a1, a2, th):
	return 0.5 * ((a2 * a2) * (math.sqrt(2.0) * math.cos(th)))
function code(a1, a2, th)
	return Float64(0.5 * Float64(Float64(a2 * a2) * Float64(sqrt(2.0) * cos(th))))
end
function tmp = code(a1, a2, th)
	tmp = 0.5 * ((a2 * a2) * (sqrt(2.0) * cos(th)));
end
code[a1_, a2_, th_] := N[(0.5 * N[(N[(a2 * a2), $MachinePrecision] * N[(N[Sqrt[2.0], $MachinePrecision] * N[Cos[th], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
0.5 \cdot \left(\left(a2 \cdot a2\right) \cdot \left(\sqrt{2} \cdot \cos th\right)\right)
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. associate-*l/N/A

      \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. associate-*l/N/A

      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
    3. frac-addN/A

      \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
    4. rem-square-sqrtN/A

      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
    5. div-invN/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
    6. metadata-evalN/A

      \[\leadsto \left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \color{blue}{\frac{1}{2}} \]
    7. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
  4. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{2}, \cos th \cdot \left(a2 \cdot a2\right), \sqrt{2} \cdot \left(\cos th \cdot \left(a1 \cdot a1\right)\right)\right) \cdot 0.5} \]
  5. Taylor expanded in a2 around inf

    \[\leadsto \color{blue}{\left({a2}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right)} \cdot \frac{1}{2} \]
  6. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\left({a2}^{2} \cdot \left(\cos th \cdot \sqrt{2}\right)\right)} \cdot \frac{1}{2} \]
    2. unpow2N/A

      \[\leadsto \left(\color{blue}{\left(a2 \cdot a2\right)} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) \cdot \frac{1}{2} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \left(\color{blue}{\left(a2 \cdot a2\right)} \cdot \left(\cos th \cdot \sqrt{2}\right)\right) \cdot \frac{1}{2} \]
    4. *-commutativeN/A

      \[\leadsto \left(\left(a2 \cdot a2\right) \cdot \color{blue}{\left(\sqrt{2} \cdot \cos th\right)}\right) \cdot \frac{1}{2} \]
    5. *-lowering-*.f64N/A

      \[\leadsto \left(\left(a2 \cdot a2\right) \cdot \color{blue}{\left(\sqrt{2} \cdot \cos th\right)}\right) \cdot \frac{1}{2} \]
    6. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \left(\left(a2 \cdot a2\right) \cdot \left(\color{blue}{\sqrt{2}} \cdot \cos th\right)\right) \cdot \frac{1}{2} \]
    7. cos-lowering-cos.f6456.4

      \[\leadsto \left(\left(a2 \cdot a2\right) \cdot \left(\sqrt{2} \cdot \color{blue}{\cos th}\right)\right) \cdot 0.5 \]
  7. Simplified56.4%

    \[\leadsto \color{blue}{\left(\left(a2 \cdot a2\right) \cdot \left(\sqrt{2} \cdot \cos th\right)\right)} \cdot 0.5 \]
  8. Final simplification56.4%

    \[\leadsto 0.5 \cdot \left(\left(a2 \cdot a2\right) \cdot \left(\sqrt{2} \cdot \cos th\right)\right) \]
  9. Add Preprocessing

Alternative 8: 65.7% accurate, 8.3× speedup?

\[\begin{array}{l} \\ 0.5 \cdot \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \end{array} \]
(FPCore (a1 a2 th)
 :precision binary64
 (* 0.5 (* (sqrt 2.0) (fma a1 a1 (* a2 a2)))))
double code(double a1, double a2, double th) {
	return 0.5 * (sqrt(2.0) * fma(a1, a1, (a2 * a2)));
}
function code(a1, a2, th)
	return Float64(0.5 * Float64(sqrt(2.0) * fma(a1, a1, Float64(a2 * a2))))
end
code[a1_, a2_, th_] := N[(0.5 * N[(N[Sqrt[2.0], $MachinePrecision] * N[(a1 * a1 + N[(a2 * a2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
0.5 \cdot \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right)
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. associate-*l/N/A

      \[\leadsto \color{blue}{\frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}}} + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
    2. associate-*l/N/A

      \[\leadsto \frac{\cos th \cdot \left(a1 \cdot a1\right)}{\sqrt{2}} + \color{blue}{\frac{\cos th \cdot \left(a2 \cdot a2\right)}{\sqrt{2}}} \]
    3. frac-addN/A

      \[\leadsto \color{blue}{\frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\sqrt{2} \cdot \sqrt{2}}} \]
    4. rem-square-sqrtN/A

      \[\leadsto \frac{\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)}{\color{blue}{2}} \]
    5. div-invN/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
    6. metadata-evalN/A

      \[\leadsto \left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \color{blue}{\frac{1}{2}} \]
    7. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\left(\left(\cos th \cdot \left(a1 \cdot a1\right)\right) \cdot \sqrt{2} + \sqrt{2} \cdot \left(\cos th \cdot \left(a2 \cdot a2\right)\right)\right) \cdot \frac{1}{2}} \]
  4. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\sqrt{2}, \cos th \cdot \left(a2 \cdot a2\right), \sqrt{2} \cdot \left(\cos th \cdot \left(a1 \cdot a1\right)\right)\right) \cdot 0.5} \]
  5. Taylor expanded in th around 0

    \[\leadsto \color{blue}{\left({a1}^{2} \cdot \sqrt{2} + {a2}^{2} \cdot \sqrt{2}\right)} \cdot \frac{1}{2} \]
  6. Step-by-step derivation
    1. distribute-rgt-outN/A

      \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \cdot \frac{1}{2} \]
    2. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \left({a1}^{2} + {a2}^{2}\right)\right)} \cdot \frac{1}{2} \]
    3. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \left(\color{blue}{\sqrt{2}} \cdot \left({a1}^{2} + {a2}^{2}\right)\right) \cdot \frac{1}{2} \]
    4. unpow2N/A

      \[\leadsto \left(\sqrt{2} \cdot \left(\color{blue}{a1 \cdot a1} + {a2}^{2}\right)\right) \cdot \frac{1}{2} \]
    5. accelerator-lowering-fma.f64N/A

      \[\leadsto \left(\sqrt{2} \cdot \color{blue}{\mathsf{fma}\left(a1, a1, {a2}^{2}\right)}\right) \cdot \frac{1}{2} \]
    6. unpow2N/A

      \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot \frac{1}{2} \]
    7. *-lowering-*.f6466.2

      \[\leadsto \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, \color{blue}{a2 \cdot a2}\right)\right) \cdot 0.5 \]
  7. Simplified66.2%

    \[\leadsto \color{blue}{\left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right)} \cdot 0.5 \]
  8. Final simplification66.2%

    \[\leadsto 0.5 \cdot \left(\sqrt{2} \cdot \mathsf{fma}\left(a1, a1, a2 \cdot a2\right)\right) \]
  9. Add Preprocessing

Alternative 9: 39.5% accurate, 9.9× speedup?

\[\begin{array}{l} \\ a2 \cdot \frac{a2}{\sqrt{2}} \end{array} \]
(FPCore (a1 a2 th) :precision binary64 (* a2 (/ a2 (sqrt 2.0))))
double code(double a1, double a2, double th) {
	return a2 * (a2 / sqrt(2.0));
}
real(8) function code(a1, a2, th)
    real(8), intent (in) :: a1
    real(8), intent (in) :: a2
    real(8), intent (in) :: th
    code = a2 * (a2 / sqrt(2.0d0))
end function
public static double code(double a1, double a2, double th) {
	return a2 * (a2 / Math.sqrt(2.0));
}
def code(a1, a2, th):
	return a2 * (a2 / math.sqrt(2.0))
function code(a1, a2, th)
	return Float64(a2 * Float64(a2 / sqrt(2.0)))
end
function tmp = code(a1, a2, th)
	tmp = a2 * (a2 / sqrt(2.0));
end
code[a1_, a2_, th_] := N[(a2 * N[(a2 / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
a2 \cdot \frac{a2}{\sqrt{2}}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
  2. Add Preprocessing
  3. Taylor expanded in th around 0

    \[\leadsto \color{blue}{\frac{{a1}^{2}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}}} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \frac{\color{blue}{a1 \cdot a1}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}} \]
    2. associate-/l*N/A

      \[\leadsto \color{blue}{a1 \cdot \frac{a1}{\sqrt{2}}} + \frac{{a2}^{2}}{\sqrt{2}} \]
    3. accelerator-lowering-fma.f64N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{{a2}^{2}}{\sqrt{2}}\right)} \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \color{blue}{\frac{a1}{\sqrt{2}}}, \frac{{a2}^{2}}{\sqrt{2}}\right) \]
    5. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\color{blue}{\sqrt{2}}}, \frac{{a2}^{2}}{\sqrt{2}}\right) \]
    6. /-lowering-/.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \color{blue}{\frac{{a2}^{2}}{\sqrt{2}}}\right) \]
    7. unpow2N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}}\right) \]
    8. *-lowering-*.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}}\right) \]
    9. sqrt-lowering-sqrt.f6466.2

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{a2 \cdot a2}{\color{blue}{\sqrt{2}}}\right) \]
  5. Simplified66.2%

    \[\leadsto \color{blue}{\mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{a2 \cdot a2}{\sqrt{2}}\right)} \]
  6. Step-by-step derivation
    1. associate-*r/N/A

      \[\leadsto \color{blue}{\frac{a1 \cdot a1}{\sqrt{2}}} + \frac{a2 \cdot a2}{\sqrt{2}} \]
    2. clear-numN/A

      \[\leadsto \color{blue}{\frac{1}{\frac{\sqrt{2}}{a1 \cdot a1}}} + \frac{a2 \cdot a2}{\sqrt{2}} \]
    3. clear-numN/A

      \[\leadsto \frac{1}{\frac{\sqrt{2}}{a1 \cdot a1}} + \color{blue}{\frac{1}{\frac{\sqrt{2}}{a2 \cdot a2}}} \]
    4. frac-addN/A

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{\sqrt{2}}{a2 \cdot a2} + \frac{\sqrt{2}}{a1 \cdot a1} \cdot 1}{\frac{\sqrt{2}}{a1 \cdot a1} \cdot \frac{\sqrt{2}}{a2 \cdot a2}}} \]
    5. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{\sqrt{2}}{a2 \cdot a2} + \frac{\sqrt{2}}{a1 \cdot a1} \cdot 1}{\frac{\sqrt{2}}{a1 \cdot a1} \cdot \frac{\sqrt{2}}{a2 \cdot a2}}} \]
  7. Applied egg-rr27.5%

    \[\leadsto \color{blue}{\frac{\frac{\sqrt{2}}{a2 \cdot a2} + \frac{\sqrt{2}}{a1 \cdot a1} \cdot 1}{\frac{\sqrt{2}}{a1 \cdot a1} \cdot \frac{\sqrt{2}}{a2 \cdot a2}}} \]
  8. Taylor expanded in a2 around inf

    \[\leadsto \color{blue}{\frac{{a2}^{2}}{\sqrt{2}}} \]
  9. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}} \]
    2. associate-/l*N/A

      \[\leadsto \color{blue}{a2 \cdot \frac{a2}{\sqrt{2}}} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{a2 \cdot \frac{a2}{\sqrt{2}}} \]
    4. /-lowering-/.f64N/A

      \[\leadsto a2 \cdot \color{blue}{\frac{a2}{\sqrt{2}}} \]
    5. sqrt-lowering-sqrt.f6440.0

      \[\leadsto a2 \cdot \frac{a2}{\color{blue}{\sqrt{2}}} \]
  10. Simplified40.0%

    \[\leadsto \color{blue}{a2 \cdot \frac{a2}{\sqrt{2}}} \]
  11. Add Preprocessing

Alternative 10: 39.5% accurate, 10.2× speedup?

\[\begin{array}{l} \\ \left(a2 \cdot a2\right) \cdot \left(\sqrt{2} \cdot 0.5\right) \end{array} \]
(FPCore (a1 a2 th) :precision binary64 (* (* a2 a2) (* (sqrt 2.0) 0.5)))
double code(double a1, double a2, double th) {
	return (a2 * a2) * (sqrt(2.0) * 0.5);
}
real(8) function code(a1, a2, th)
    real(8), intent (in) :: a1
    real(8), intent (in) :: a2
    real(8), intent (in) :: th
    code = (a2 * a2) * (sqrt(2.0d0) * 0.5d0)
end function
public static double code(double a1, double a2, double th) {
	return (a2 * a2) * (Math.sqrt(2.0) * 0.5);
}
def code(a1, a2, th):
	return (a2 * a2) * (math.sqrt(2.0) * 0.5)
function code(a1, a2, th)
	return Float64(Float64(a2 * a2) * Float64(sqrt(2.0) * 0.5))
end
function tmp = code(a1, a2, th)
	tmp = (a2 * a2) * (sqrt(2.0) * 0.5);
end
code[a1_, a2_, th_] := N[(N[(a2 * a2), $MachinePrecision] * N[(N[Sqrt[2.0], $MachinePrecision] * 0.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(a2 \cdot a2\right) \cdot \left(\sqrt{2} \cdot 0.5\right)
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
  2. Add Preprocessing
  3. Taylor expanded in th around 0

    \[\leadsto \color{blue}{\frac{{a1}^{2}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}}} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \frac{\color{blue}{a1 \cdot a1}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}} \]
    2. associate-/l*N/A

      \[\leadsto \color{blue}{a1 \cdot \frac{a1}{\sqrt{2}}} + \frac{{a2}^{2}}{\sqrt{2}} \]
    3. accelerator-lowering-fma.f64N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{{a2}^{2}}{\sqrt{2}}\right)} \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \color{blue}{\frac{a1}{\sqrt{2}}}, \frac{{a2}^{2}}{\sqrt{2}}\right) \]
    5. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\color{blue}{\sqrt{2}}}, \frac{{a2}^{2}}{\sqrt{2}}\right) \]
    6. /-lowering-/.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \color{blue}{\frac{{a2}^{2}}{\sqrt{2}}}\right) \]
    7. unpow2N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}}\right) \]
    8. *-lowering-*.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}}\right) \]
    9. sqrt-lowering-sqrt.f6466.2

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{a2 \cdot a2}{\color{blue}{\sqrt{2}}}\right) \]
  5. Simplified66.2%

    \[\leadsto \color{blue}{\mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{a2 \cdot a2}{\sqrt{2}}\right)} \]
  6. Step-by-step derivation
    1. associate-*r/N/A

      \[\leadsto \color{blue}{\frac{a1 \cdot a1}{\sqrt{2}}} + \frac{a2 \cdot a2}{\sqrt{2}} \]
    2. clear-numN/A

      \[\leadsto \color{blue}{\frac{1}{\frac{\sqrt{2}}{a1 \cdot a1}}} + \frac{a2 \cdot a2}{\sqrt{2}} \]
    3. clear-numN/A

      \[\leadsto \frac{1}{\frac{\sqrt{2}}{a1 \cdot a1}} + \color{blue}{\frac{1}{\frac{\sqrt{2}}{a2 \cdot a2}}} \]
    4. frac-addN/A

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{\sqrt{2}}{a2 \cdot a2} + \frac{\sqrt{2}}{a1 \cdot a1} \cdot 1}{\frac{\sqrt{2}}{a1 \cdot a1} \cdot \frac{\sqrt{2}}{a2 \cdot a2}}} \]
    5. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{1 \cdot \frac{\sqrt{2}}{a2 \cdot a2} + \frac{\sqrt{2}}{a1 \cdot a1} \cdot 1}{\frac{\sqrt{2}}{a1 \cdot a1} \cdot \frac{\sqrt{2}}{a2 \cdot a2}}} \]
  7. Applied egg-rr27.5%

    \[\leadsto \color{blue}{\frac{\frac{\sqrt{2}}{a2 \cdot a2} + \frac{\sqrt{2}}{a1 \cdot a1} \cdot 1}{\frac{\sqrt{2}}{a1 \cdot a1} \cdot \frac{\sqrt{2}}{a2 \cdot a2}}} \]
  8. Taylor expanded in a2 around inf

    \[\leadsto \color{blue}{\frac{{a2}^{2}}{\sqrt{2}}} \]
  9. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}} \]
    2. associate-/l*N/A

      \[\leadsto \color{blue}{a2 \cdot \frac{a2}{\sqrt{2}}} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{a2 \cdot \frac{a2}{\sqrt{2}}} \]
    4. /-lowering-/.f64N/A

      \[\leadsto a2 \cdot \color{blue}{\frac{a2}{\sqrt{2}}} \]
    5. sqrt-lowering-sqrt.f6440.0

      \[\leadsto a2 \cdot \frac{a2}{\color{blue}{\sqrt{2}}} \]
  10. Simplified40.0%

    \[\leadsto \color{blue}{a2 \cdot \frac{a2}{\sqrt{2}}} \]
  11. Step-by-step derivation
    1. associate-*r/N/A

      \[\leadsto \color{blue}{\frac{a2 \cdot a2}{\sqrt{2}}} \]
    2. div-invN/A

      \[\leadsto \color{blue}{\left(a2 \cdot a2\right) \cdot \frac{1}{\sqrt{2}}} \]
    3. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\left(a2 \cdot a2\right) \cdot \frac{1}{\sqrt{2}}} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\left(a2 \cdot a2\right)} \cdot \frac{1}{\sqrt{2}} \]
    5. pow1/2N/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \frac{1}{\color{blue}{{2}^{\frac{1}{2}}}} \]
    6. metadata-evalN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \frac{1}{{2}^{\color{blue}{\left(\frac{-1}{2} + 1\right)}}} \]
    7. metadata-evalN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \frac{1}{{2}^{\left(\color{blue}{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)} + 1\right)}} \]
    8. pow-plusN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \frac{1}{\color{blue}{{2}^{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)} \cdot 2}} \]
    9. pow-flipN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \frac{1}{\color{blue}{\frac{1}{{2}^{\frac{1}{2}}}} \cdot 2} \]
    10. pow1/2N/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \frac{1}{\frac{1}{\color{blue}{\sqrt{2}}} \cdot 2} \]
    11. metadata-evalN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \frac{1}{\frac{1}{\sqrt{2}} \cdot \color{blue}{\frac{1}{\frac{1}{2}}}} \]
    12. div-invN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \frac{1}{\color{blue}{\frac{\frac{1}{\sqrt{2}}}{\frac{1}{2}}}} \]
    13. clear-numN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \color{blue}{\frac{\frac{1}{2}}{\frac{1}{\sqrt{2}}}} \]
    14. div-invN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \color{blue}{\left(\frac{1}{2} \cdot \frac{1}{\frac{1}{\sqrt{2}}}\right)} \]
    15. clear-numN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \left(\frac{1}{2} \cdot \color{blue}{\frac{\sqrt{2}}{1}}\right) \]
    16. div-invN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \left(\frac{1}{2} \cdot \color{blue}{\left(\sqrt{2} \cdot \frac{1}{1}\right)}\right) \]
    17. metadata-evalN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \left(\frac{1}{2} \cdot \left(\sqrt{2} \cdot \color{blue}{1}\right)\right) \]
    18. *-rgt-identityN/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \left(\frac{1}{2} \cdot \color{blue}{\sqrt{2}}\right) \]
    19. *-lowering-*.f64N/A

      \[\leadsto \left(a2 \cdot a2\right) \cdot \color{blue}{\left(\frac{1}{2} \cdot \sqrt{2}\right)} \]
    20. sqrt-lowering-sqrt.f6440.0

      \[\leadsto \left(a2 \cdot a2\right) \cdot \left(0.5 \cdot \color{blue}{\sqrt{2}}\right) \]
  12. Applied egg-rr40.0%

    \[\leadsto \color{blue}{\left(a2 \cdot a2\right) \cdot \left(0.5 \cdot \sqrt{2}\right)} \]
  13. Final simplification40.0%

    \[\leadsto \left(a2 \cdot a2\right) \cdot \left(\sqrt{2} \cdot 0.5\right) \]
  14. Add Preprocessing

Alternative 11: 39.6% accurate, 10.2× speedup?

\[\begin{array}{l} \\ 0.5 \cdot \left(a1 \cdot \left(\sqrt{2} \cdot a1\right)\right) \end{array} \]
(FPCore (a1 a2 th) :precision binary64 (* 0.5 (* a1 (* (sqrt 2.0) a1))))
double code(double a1, double a2, double th) {
	return 0.5 * (a1 * (sqrt(2.0) * a1));
}
real(8) function code(a1, a2, th)
    real(8), intent (in) :: a1
    real(8), intent (in) :: a2
    real(8), intent (in) :: th
    code = 0.5d0 * (a1 * (sqrt(2.0d0) * a1))
end function
public static double code(double a1, double a2, double th) {
	return 0.5 * (a1 * (Math.sqrt(2.0) * a1));
}
def code(a1, a2, th):
	return 0.5 * (a1 * (math.sqrt(2.0) * a1))
function code(a1, a2, th)
	return Float64(0.5 * Float64(a1 * Float64(sqrt(2.0) * a1)))
end
function tmp = code(a1, a2, th)
	tmp = 0.5 * (a1 * (sqrt(2.0) * a1));
end
code[a1_, a2_, th_] := N[(0.5 * N[(a1 * N[(N[Sqrt[2.0], $MachinePrecision] * a1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
0.5 \cdot \left(a1 \cdot \left(\sqrt{2} \cdot a1\right)\right)
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{\cos th}{\sqrt{2}} \cdot \left(a1 \cdot a1\right) + \frac{\cos th}{\sqrt{2}} \cdot \left(a2 \cdot a2\right) \]
  2. Add Preprocessing
  3. Taylor expanded in th around 0

    \[\leadsto \color{blue}{\frac{{a1}^{2}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}}} \]
  4. Step-by-step derivation
    1. unpow2N/A

      \[\leadsto \frac{\color{blue}{a1 \cdot a1}}{\sqrt{2}} + \frac{{a2}^{2}}{\sqrt{2}} \]
    2. associate-/l*N/A

      \[\leadsto \color{blue}{a1 \cdot \frac{a1}{\sqrt{2}}} + \frac{{a2}^{2}}{\sqrt{2}} \]
    3. accelerator-lowering-fma.f64N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{{a2}^{2}}{\sqrt{2}}\right)} \]
    4. /-lowering-/.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \color{blue}{\frac{a1}{\sqrt{2}}}, \frac{{a2}^{2}}{\sqrt{2}}\right) \]
    5. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\color{blue}{\sqrt{2}}}, \frac{{a2}^{2}}{\sqrt{2}}\right) \]
    6. /-lowering-/.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \color{blue}{\frac{{a2}^{2}}{\sqrt{2}}}\right) \]
    7. unpow2N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}}\right) \]
    8. *-lowering-*.f64N/A

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{\color{blue}{a2 \cdot a2}}{\sqrt{2}}\right) \]
    9. sqrt-lowering-sqrt.f6466.2

      \[\leadsto \mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{a2 \cdot a2}{\color{blue}{\sqrt{2}}}\right) \]
  5. Simplified66.2%

    \[\leadsto \color{blue}{\mathsf{fma}\left(a1, \frac{a1}{\sqrt{2}}, \frac{a2 \cdot a2}{\sqrt{2}}\right)} \]
  6. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \color{blue}{\frac{a2 \cdot a2}{\sqrt{2}} + a1 \cdot \frac{a1}{\sqrt{2}}} \]
    2. flip-+N/A

      \[\leadsto \color{blue}{\frac{\frac{a2 \cdot a2}{\sqrt{2}} \cdot \frac{a2 \cdot a2}{\sqrt{2}} - \left(a1 \cdot \frac{a1}{\sqrt{2}}\right) \cdot \left(a1 \cdot \frac{a1}{\sqrt{2}}\right)}{\frac{a2 \cdot a2}{\sqrt{2}} - a1 \cdot \frac{a1}{\sqrt{2}}}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{\frac{a2 \cdot a2}{\sqrt{2}} \cdot \frac{a2 \cdot a2}{\sqrt{2}} - \left(a1 \cdot \frac{a1}{\sqrt{2}}\right) \cdot \left(a1 \cdot \frac{a1}{\sqrt{2}}\right)}{\frac{a2 \cdot a2}{\sqrt{2}} - a1 \cdot \frac{a1}{\sqrt{2}}}} \]
  7. Applied egg-rr18.4%

    \[\leadsto \color{blue}{\frac{\frac{\mathsf{fma}\left(a2, a2, a1 \cdot a1\right) \cdot \left(\left(a2 + a1\right) \cdot \left(a2 - a1\right)\right)}{2}}{\frac{\left(a2 + a1\right) \cdot \left(a2 - a1\right)}{\sqrt{2}}}} \]
  8. Taylor expanded in a2 around 0

    \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \sqrt{2}\right)} \]
  9. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\frac{1}{2} \cdot \left({a1}^{2} \cdot \sqrt{2}\right)} \]
    2. unpow2N/A

      \[\leadsto \frac{1}{2} \cdot \left(\color{blue}{\left(a1 \cdot a1\right)} \cdot \sqrt{2}\right) \]
    3. associate-*l*N/A

      \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(a1 \cdot \left(a1 \cdot \sqrt{2}\right)\right)} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \frac{1}{2} \cdot \color{blue}{\left(a1 \cdot \left(a1 \cdot \sqrt{2}\right)\right)} \]
    5. *-commutativeN/A

      \[\leadsto \frac{1}{2} \cdot \left(a1 \cdot \color{blue}{\left(\sqrt{2} \cdot a1\right)}\right) \]
    6. *-lowering-*.f64N/A

      \[\leadsto \frac{1}{2} \cdot \left(a1 \cdot \color{blue}{\left(\sqrt{2} \cdot a1\right)}\right) \]
    7. sqrt-lowering-sqrt.f6439.3

      \[\leadsto 0.5 \cdot \left(a1 \cdot \left(\color{blue}{\sqrt{2}} \cdot a1\right)\right) \]
  10. Simplified39.3%

    \[\leadsto \color{blue}{0.5 \cdot \left(a1 \cdot \left(\sqrt{2} \cdot a1\right)\right)} \]
  11. Add Preprocessing

Reproduce

?
herbie shell --seed 2024194 
(FPCore (a1 a2 th)
  :name "Migdal et al, Equation (64)"
  :precision binary64
  (+ (* (/ (cos th) (sqrt 2.0)) (* a1 a1)) (* (/ (cos th) (sqrt 2.0)) (* a2 a2))))