
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(* (* (PI) (log (* alpha alpha))) (+ 1.0 (* (* t_0 cosTheta) cosTheta))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t\_0}{\left(\mathsf{PI}\left(\right) \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 + \left(t\_0 \cdot cosTheta\right) \cdot cosTheta\right)}
\end{array}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 9 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(* (* (PI) (log (* alpha alpha))) (+ 1.0 (* (* t_0 cosTheta) cosTheta))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t\_0}{\left(\mathsf{PI}\left(\right) \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 + \left(t\_0 \cdot cosTheta\right) \cdot cosTheta\right)}
\end{array}
\end{array}
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(* (+ (* (* cosTheta t_0) cosTheta) 1.0) (* (+ (PI) (PI)) (log alpha))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t\_0}{\left(\left(cosTheta \cdot t\_0\right) \cdot cosTheta + 1\right) \cdot \left(\left(\mathsf{PI}\left(\right) + \mathsf{PI}\left(\right)\right) \cdot \log \alpha\right)}
\end{array}
\end{array}
Initial program 98.6%
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
log-prodN/A
distribute-rgt-inN/A
distribute-lft-outN/A
lower-*.f32N/A
lower-log.f32N/A
lower-+.f3298.7
Applied rewrites98.7%
Final simplification98.7%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (* (- 1.0 (* cosTheta cosTheta)) (log alpha)) (* 2.0 (PI)))))
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{\left(\left(1 - cosTheta \cdot cosTheta\right) \cdot \log \alpha\right) \cdot \left(2 \cdot \mathsf{PI}\left(\right)\right)}
\end{array}
Initial program 98.6%
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
log-prodN/A
distribute-rgt-inN/A
distribute-lft-outN/A
lower-*.f32N/A
lower-log.f32N/A
lower-+.f3298.7
Applied rewrites98.7%
Taylor expanded in alpha around 0
associate-*r*N/A
lower-*.f32N/A
lower-*.f32N/A
lower-PI.f32N/A
*-commutativeN/A
lower-*.f32N/A
mul-1-negN/A
unsub-negN/A
lower--.f32N/A
unpow2N/A
lower-*.f32N/A
lower-log.f3297.2
Applied rewrites97.2%
Final simplification97.2%
(FPCore (cosTheta alpha) :precision binary32 (/ (/ (- (* alpha alpha) 1.0) (PI)) (log (* alpha alpha))))
\begin{array}{l}
\\
\frac{\frac{\alpha \cdot \alpha - 1}{\mathsf{PI}\left(\right)}}{\log \left(\alpha \cdot \alpha\right)}
\end{array}
Initial program 98.6%
Taylor expanded in cosTheta around 0
associate-/r*N/A
lower-/.f32N/A
lower-/.f32N/A
sub-negN/A
unpow2N/A
metadata-evalN/A
lower-fma.f32N/A
lower-PI.f32N/A
lower-log.f32N/A
unpow2N/A
lower-*.f3210.8
Applied rewrites10.3%
Applied rewrites93.5%
Final simplification93.5%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (* (PI) (log alpha)) 2.0)))
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{\left(\mathsf{PI}\left(\right) \cdot \log \alpha\right) \cdot 2}
\end{array}
Initial program 98.6%
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
log-prodN/A
distribute-rgt-inN/A
distribute-lft-outN/A
lower-*.f32N/A
lower-log.f32N/A
lower-+.f3298.7
Applied rewrites98.7%
Taylor expanded in cosTheta around 0
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-log.f32N/A
lower-PI.f3293.5
Applied rewrites93.5%
Final simplification93.5%
(FPCore (cosTheta alpha) :precision binary32 (/ (/ -1.0 (PI)) (* 2.0 (log alpha))))
\begin{array}{l}
\\
\frac{\frac{-1}{\mathsf{PI}\left(\right)}}{2 \cdot \log \alpha}
\end{array}
Initial program 98.6%
Taylor expanded in cosTheta around 0
associate-/r*N/A
lower-/.f32N/A
lower-/.f32N/A
sub-negN/A
unpow2N/A
metadata-evalN/A
lower-fma.f32N/A
lower-PI.f32N/A
lower-log.f32N/A
unpow2N/A
lower-*.f3210.4
Applied rewrites10.3%
Taylor expanded in alpha around 0
Applied rewrites64.6%
Taylor expanded in alpha around 0
Applied rewrites64.6%
Final simplification64.6%
(FPCore (cosTheta alpha) :precision binary32 (/ -0.5 (* (PI) (log alpha))))
\begin{array}{l}
\\
\frac{-0.5}{\mathsf{PI}\left(\right) \cdot \log \alpha}
\end{array}
Initial program 98.6%
Taylor expanded in cosTheta around 0
associate-/r*N/A
lower-/.f32N/A
lower-/.f32N/A
sub-negN/A
unpow2N/A
metadata-evalN/A
lower-fma.f32N/A
lower-PI.f32N/A
lower-log.f32N/A
unpow2N/A
lower-*.f3210.8
Applied rewrites10.0%
Taylor expanded in alpha around 0
Applied rewrites64.5%
Final simplification64.5%
(FPCore (cosTheta alpha) :precision binary32 (fma (/ alpha (fma (* (fma alpha alpha -1.0) cosTheta) cosTheta 1.0)) (/ alpha (* (/ 0.0 0.0) (PI))) (/ -1.0 (* (PI) (/ 0.0 0.0)))))
\begin{array}{l}
\\
\mathsf{fma}\left(\frac{\alpha}{\mathsf{fma}\left(\mathsf{fma}\left(\alpha, \alpha, -1\right) \cdot cosTheta, cosTheta, 1\right)}, \frac{\alpha}{\frac{0}{0} \cdot \mathsf{PI}\left(\right)}, \frac{-1}{\mathsf{PI}\left(\right) \cdot \frac{0}{0}}\right)
\end{array}
Initial program 98.6%
Applied rewrites-0.0%
Taylor expanded in cosTheta around 0
lower-PI.f32-0.0
Applied rewrites-0.0%
Final simplification-0.0%
(FPCore (cosTheta alpha) :precision binary32 (fma (/ alpha 1.0) (/ alpha (* (/ 0.0 0.0) (PI))) (/ -1.0 (* (* (fma (* -1.0 cosTheta) cosTheta 1.0) (PI)) (/ 0.0 0.0)))))
\begin{array}{l}
\\
\mathsf{fma}\left(\frac{\alpha}{1}, \frac{\alpha}{\frac{0}{0} \cdot \mathsf{PI}\left(\right)}, \frac{-1}{\left(\mathsf{fma}\left(-1 \cdot cosTheta, cosTheta, 1\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \frac{0}{0}}\right)
\end{array}
Initial program 98.6%
Applied rewrites-0.0%
Applied rewrites-0.0%
Taylor expanded in alpha around 0
Applied rewrites-0.0%
Taylor expanded in cosTheta around 0
Applied rewrites-0.0%
Final simplification-0.0%
(FPCore (cosTheta alpha) :precision binary32 (/ -1.0 (* (PI) (/ 0.0 0.0))))
\begin{array}{l}
\\
\frac{-1}{\mathsf{PI}\left(\right) \cdot \frac{0}{0}}
\end{array}
Initial program 98.6%
lift--.f32N/A
sub-negN/A
lift-*.f32N/A
lower-fma.f32N/A
metadata-eval12.2
lift-*.f32N/A
lift-*.f32N/A
associate-*l*N/A
*-commutativeN/A
associate-*r*N/A
lower-*.f32N/A
Applied rewrites-0.0%
Taylor expanded in cosTheta around 0
lower-PI.f32-0.0
Applied rewrites-0.0%
Taylor expanded in alpha around 0
Applied rewrites-0.0%
herbie shell --seed 2024276
(FPCore (cosTheta alpha)
:name "GTR1 distribution"
:precision binary32
:pre (and (and (<= 0.0 cosTheta) (<= cosTheta 1.0)) (and (<= 0.0001 alpha) (<= alpha 1.0)))
(/ (- (* alpha alpha) 1.0) (* (* (PI) (log (* alpha alpha))) (+ 1.0 (* (* (- (* alpha alpha) 1.0) cosTheta) cosTheta)))))