
(FPCore (v t) :precision binary64 (/ (- 1.0 (* 5.0 (* v v))) (* (* (* (PI) t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))
\begin{array}{l}
\\
\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 10 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (v t) :precision binary64 (/ (- 1.0 (* 5.0 (* v v))) (* (* (* (PI) t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))
\begin{array}{l}
\\
\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)}
\end{array}
(FPCore (v t) :precision binary64 (/ (/ (/ (fma -5.0 (* v v) 1.0) (PI)) (sqrt (* (fma (* v v) -3.0 1.0) 2.0))) (* t (- 1.0 (* v v)))))
\begin{array}{l}
\\
\frac{\frac{\frac{\mathsf{fma}\left(-5, v \cdot v, 1\right)}{\mathsf{PI}\left(\right)}}{\sqrt{\mathsf{fma}\left(v \cdot v, -3, 1\right) \cdot 2}}}{t \cdot \left(1 - v \cdot v\right)}
\end{array}
Initial program 98.8%
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f6498.7
lift-*.f64N/A
*-commutativeN/A
lower-*.f6498.7
lift--.f64N/A
lift-*.f64N/A
fp-cancel-sub-sign-invN/A
+-commutativeN/A
lower-fma.f64N/A
metadata-eval98.7
Applied rewrites98.7%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
Applied rewrites99.8%
(FPCore (v t) :precision binary64 (/ (/ (/ (fma -5.0 (* v v) 1.0) (PI)) t) (* (sqrt (* (fma (* v v) -3.0 1.0) 2.0)) (- 1.0 (* v v)))))
\begin{array}{l}
\\
\frac{\frac{\frac{\mathsf{fma}\left(-5, v \cdot v, 1\right)}{\mathsf{PI}\left(\right)}}{t}}{\sqrt{\mathsf{fma}\left(v \cdot v, -3, 1\right) \cdot 2} \cdot \left(1 - v \cdot v\right)}
\end{array}
Initial program 98.8%
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f6498.7
lift-*.f64N/A
*-commutativeN/A
lower-*.f6498.7
lift--.f64N/A
lift-*.f64N/A
fp-cancel-sub-sign-invN/A
+-commutativeN/A
lower-fma.f64N/A
metadata-eval98.7
Applied rewrites98.7%
Applied rewrites99.6%
(FPCore (v t) :precision binary64 (/ (/ (fma -5.0 (* v v) 1.0) (PI)) (* (* (sqrt (fma (* v v) -6.0 2.0)) t) (- 1.0 (* v v)))))
\begin{array}{l}
\\
\frac{\frac{\mathsf{fma}\left(-5, v \cdot v, 1\right)}{\mathsf{PI}\left(\right)}}{\left(\sqrt{\mathsf{fma}\left(v \cdot v, -6, 2\right)} \cdot t\right) \cdot \left(1 - v \cdot v\right)}
\end{array}
Initial program 98.8%
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f6498.7
lift-*.f64N/A
*-commutativeN/A
lower-*.f6498.7
lift--.f64N/A
lift-*.f64N/A
fp-cancel-sub-sign-invN/A
+-commutativeN/A
lower-fma.f64N/A
metadata-eval98.7
Applied rewrites98.7%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
Applied rewrites99.2%
Taylor expanded in v around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6499.2
Applied rewrites99.2%
(FPCore (v t) :precision binary64 (/ (fma (* v v) -5.0 1.0) (* (* (* (PI) t) (sqrt (fma (* v v) -6.0 2.0))) (- 1.0 (* v v)))))
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(v \cdot v, -5, 1\right)}{\left(\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{\mathsf{fma}\left(v \cdot v, -6, 2\right)}\right) \cdot \left(1 - v \cdot v\right)}
\end{array}
Initial program 98.8%
Taylor expanded in v around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6498.8
Applied rewrites98.8%
lift--.f64N/A
lift-*.f64N/A
fp-cancel-sub-sign-invN/A
metadata-evalN/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f6498.8
Applied rewrites98.8%
(FPCore (v t) :precision binary64 (/ (/ 1.0 (* (sqrt 2.0) (PI))) (* t (- 1.0 (* v v)))))
\begin{array}{l}
\\
\frac{\frac{1}{\sqrt{2} \cdot \mathsf{PI}\left(\right)}}{t \cdot \left(1 - v \cdot v\right)}
\end{array}
Initial program 98.8%
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f6498.7
lift-*.f64N/A
*-commutativeN/A
lower-*.f6498.7
lift--.f64N/A
lift-*.f64N/A
fp-cancel-sub-sign-invN/A
+-commutativeN/A
lower-fma.f64N/A
metadata-eval98.7
Applied rewrites98.7%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
Applied rewrites99.8%
Taylor expanded in v around 0
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6498.5
Applied rewrites98.5%
(FPCore (v t) :precision binary64 (/ (/ (fma -2.5 (* v v) 1.0) (PI)) (* (sqrt 2.0) t)))
\begin{array}{l}
\\
\frac{\frac{\mathsf{fma}\left(-2.5, v \cdot v, 1\right)}{\mathsf{PI}\left(\right)}}{\sqrt{2} \cdot t}
\end{array}
Initial program 98.8%
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f6498.7
lift-*.f64N/A
*-commutativeN/A
lower-*.f6498.7
lift--.f64N/A
lift-*.f64N/A
fp-cancel-sub-sign-invN/A
+-commutativeN/A
lower-fma.f64N/A
metadata-eval98.7
Applied rewrites98.7%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
Applied rewrites99.8%
Taylor expanded in v around 0
associate-*r/N/A
div-add-revN/A
lower-/.f64N/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6498.2
Applied rewrites98.2%
Applied rewrites98.5%
(FPCore (v t) :precision binary64 (* (/ 1.0 (sqrt 2.0)) (/ (/ 1.0 (PI)) t)))
\begin{array}{l}
\\
\frac{1}{\sqrt{2}} \cdot \frac{\frac{1}{\mathsf{PI}\left(\right)}}{t}
\end{array}
Initial program 98.8%
Taylor expanded in v around 0
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6497.6
Applied rewrites97.6%
Applied rewrites97.8%
Taylor expanded in t around 0
Applied rewrites98.2%
(FPCore (v t) :precision binary64 (/ (/ 1.0 t) (* (sqrt 2.0) (PI))))
\begin{array}{l}
\\
\frac{\frac{1}{t}}{\sqrt{2} \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 98.8%
Taylor expanded in v around 0
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6497.6
Applied rewrites97.6%
Applied rewrites97.5%
Applied rewrites98.2%
(FPCore (v t) :precision binary64 (/ 1.0 (* (* (sqrt 2.0) (PI)) t)))
\begin{array}{l}
\\
\frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t}
\end{array}
Initial program 98.8%
Taylor expanded in v around 0
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6497.6
Applied rewrites97.6%
(FPCore (v t) :precision binary64 (/ 1.0 (* (* (PI) t) (sqrt 2.0))))
\begin{array}{l}
\\
\frac{1}{\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{2}}
\end{array}
Initial program 98.8%
Taylor expanded in v around 0
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6497.6
Applied rewrites97.6%
Applied rewrites97.5%
herbie shell --seed 2025012
(FPCore (v t)
:name "Falkner and Boettcher, Equation (20:1,3)"
:precision binary64
(/ (- 1.0 (* 5.0 (* v v))) (* (* (* (PI) t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))