
(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 13 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 (/ (/ (- 1.0 (pow alpha 4.0)) (- -1.0 (* alpha alpha))) (* (+ (* (* cosTheta (- (* alpha alpha) 1.0)) cosTheta) 1.0) (* (* (log alpha) 2.0) (PI)))))
\begin{array}{l}
\\
\frac{\frac{1 - {\alpha}^{4}}{-1 - \alpha \cdot \alpha}}{\left(\left(cosTheta \cdot \left(\alpha \cdot \alpha - 1\right)\right) \cdot cosTheta + 1\right) \cdot \left(\left(\log \alpha \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right)}
\end{array}
Initial program 98.3%
lift--.f32N/A
sub-negN/A
+-commutativeN/A
flip-+N/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
lower-/.f32N/A
metadata-evalN/A
lower--.f32N/A
pow2N/A
lift-*.f32N/A
pow-prod-downN/A
pow-prod-upN/A
lower-pow.f32N/A
metadata-evalN/A
lower--.f32N/A
metadata-eval98.2
Applied rewrites98.2%
Taylor expanded in alpha around 0
lower-*.f32N/A
lower-log.f3298.3
Applied rewrites98.3%
Final simplification98.3%
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(* (* (log (* alpha alpha)) (PI)) (+ (* (* cosTheta t_0) cosTheta) 1.0)))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t\_0}{\left(\log \left(\alpha \cdot \alpha\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \left(\left(cosTheta \cdot t\_0\right) \cdot cosTheta + 1\right)}
\end{array}
\end{array}
Initial program 98.3%
Final simplification98.3%
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(* (* (+ (PI) (PI)) (log alpha)) (+ (* (* cosTheta t_0) cosTheta) 1.0)))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t\_0}{\left(\left(\mathsf{PI}\left(\right) + \mathsf{PI}\left(\right)\right) \cdot \log \alpha\right) \cdot \left(\left(cosTheta \cdot t\_0\right) \cdot cosTheta + 1\right)}
\end{array}
\end{array}
Initial program 98.3%
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-+.f3298.3
Applied rewrites98.3%
Final simplification98.3%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (- 1.0 (* cosTheta cosTheta)) (* (log (* alpha alpha)) (PI)))))
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{\left(1 - cosTheta \cdot cosTheta\right) \cdot \left(\log \left(\alpha \cdot \alpha\right) \cdot \mathsf{PI}\left(\right)\right)}
\end{array}
Initial program 98.3%
Taylor expanded in alpha around 0
mul-1-negN/A
unsub-negN/A
lower--.f32N/A
unpow2N/A
lower-*.f3297.4
Applied rewrites97.4%
Final simplification97.4%
(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 98.3%
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-+.f3298.3
Applied rewrites98.3%
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.f3297.3
Applied rewrites97.3%
Final simplification97.3%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (log (* alpha alpha)) (PI))))
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{\log \left(\alpha \cdot \alpha\right) \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 98.3%
Taylor expanded in cosTheta around 0
Applied rewrites94.5%
Taylor expanded in cosTheta around 0
*-commutativeN/A
lower-*.f32N/A
lower-log.f32N/A
unpow2N/A
lower-*.f32N/A
lower-PI.f3294.5
Applied rewrites94.5%
(FPCore (cosTheta alpha) :precision binary32 (/ -1.0 (* 1.0 (* (log (* alpha alpha)) (PI)))))
\begin{array}{l}
\\
\frac{-1}{1 \cdot \left(\log \left(\alpha \cdot \alpha\right) \cdot \mathsf{PI}\left(\right)\right)}
\end{array}
Initial program 98.3%
Taylor expanded in cosTheta around 0
Applied rewrites94.5%
Taylor expanded in alpha around 0
Applied rewrites67.7%
Final simplification67.7%
(FPCore (cosTheta alpha) :precision binary32 (/ -1.0 (* (* (log alpha) (PI)) 2.0)))
\begin{array}{l}
\\
\frac{-1}{\left(\log \alpha \cdot \mathsf{PI}\left(\right)\right) \cdot 2}
\end{array}
Initial program 98.3%
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-+.f3298.3
Applied rewrites98.3%
Taylor expanded in cosTheta around 0
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-log.f32N/A
lower-PI.f3294.5
Applied rewrites94.5%
Taylor expanded in alpha around 0
Applied rewrites67.7%
(FPCore (cosTheta alpha) :precision binary32 (fma -1.0 (/ (/ 1.0 (* (* (* cosTheta cosTheta) alpha) alpha)) (* (/ 0.0 0.0) (PI))) (* (/ alpha (/ 0.0 0.0)) (/ alpha (* (fma (* (fma alpha alpha -1.0) cosTheta) cosTheta 1.0) (PI))))))
\begin{array}{l}
\\
\mathsf{fma}\left(-1, \frac{\frac{1}{\left(\left(cosTheta \cdot cosTheta\right) \cdot \alpha\right) \cdot \alpha}}{\frac{0}{0} \cdot \mathsf{PI}\left(\right)}, \frac{\alpha}{\frac{0}{0}} \cdot \frac{\alpha}{\mathsf{fma}\left(\mathsf{fma}\left(\alpha, \alpha, -1\right) \cdot cosTheta, cosTheta, 1\right) \cdot \mathsf{PI}\left(\right)}\right)
\end{array}
Initial program 98.3%
Applied rewrites-0.0%
Taylor expanded in alpha around inf
*-commutativeN/A
unpow2N/A
associate-*r*N/A
lower-*.f32N/A
lower-*.f32N/A
unpow2N/A
lower-*.f32-0.0
Applied rewrites-0.0%
Final simplification-0.0%
(FPCore (cosTheta alpha)
:precision binary32
(fma
(/ (* alpha alpha) (/ 0.0 0.0))
(/ 1.0 (* (fma (- cosTheta) cosTheta 1.0) (PI)))
(/
-1.0
(*
(* (fma (* (fma alpha alpha -1.0) cosTheta) cosTheta 1.0) (PI))
(/ 0.0 0.0)))))\begin{array}{l}
\\
\mathsf{fma}\left(\frac{\alpha \cdot \alpha}{\frac{0}{0}}, \frac{1}{\mathsf{fma}\left(-cosTheta, cosTheta, 1\right) \cdot \mathsf{PI}\left(\right)}, \frac{-1}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\alpha, \alpha, -1\right) \cdot cosTheta, cosTheta, 1\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \frac{0}{0}}\right)
\end{array}
Initial program 98.3%
lift-/.f32N/A
lift--.f32N/A
div-subN/A
sub-negN/A
Applied rewrites-0.0%
Taylor expanded in alpha around 0
Applied rewrites-0.0%
Taylor expanded in alpha around 0
mul-1-negN/A
lower-neg.f32-0.0
Applied rewrites-0.0%
Final simplification-0.0%
(FPCore (cosTheta alpha) :precision binary32 (fma (/ (* alpha alpha) (/ 0.0 0.0)) (/ 1.0 (* (fma (* -1.0 cosTheta) cosTheta 1.0) (PI))) (/ -1.0 (* (* (fma (- cosTheta) cosTheta 1.0) (PI)) (/ 0.0 0.0)))))
\begin{array}{l}
\\
\mathsf{fma}\left(\frac{\alpha \cdot \alpha}{\frac{0}{0}}, \frac{1}{\mathsf{fma}\left(-1 \cdot cosTheta, cosTheta, 1\right) \cdot \mathsf{PI}\left(\right)}, \frac{-1}{\left(\mathsf{fma}\left(-cosTheta, cosTheta, 1\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \frac{0}{0}}\right)
\end{array}
Initial program 98.3%
lift-/.f32N/A
lift--.f32N/A
div-subN/A
sub-negN/A
Applied rewrites-0.0%
Taylor expanded in alpha around 0
Applied rewrites-0.0%
Taylor expanded in alpha around 0
mul-1-negN/A
lower-neg.f32-0.0
Applied rewrites-0.0%
Final simplification-0.0%
(FPCore (cosTheta alpha) :precision binary32 (fma (/ (* alpha alpha) (/ 0.0 0.0)) (/ 1.0 (* (fma (* -1.0 cosTheta) cosTheta 1.0) (PI))) (/ -1.0 (* (PI) (/ 0.0 0.0)))))
\begin{array}{l}
\\
\mathsf{fma}\left(\frac{\alpha \cdot \alpha}{\frac{0}{0}}, \frac{1}{\mathsf{fma}\left(-1 \cdot cosTheta, cosTheta, 1\right) \cdot \mathsf{PI}\left(\right)}, \frac{-1}{\mathsf{PI}\left(\right) \cdot \frac{0}{0}}\right)
\end{array}
Initial program 98.3%
lift-/.f32N/A
lift--.f32N/A
div-subN/A
sub-negN/A
Applied rewrites-0.0%
Taylor expanded in alpha around 0
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 (/ -1.0 (* (PI) (/ 0.0 0.0))))
\begin{array}{l}
\\
\frac{-1}{\mathsf{PI}\left(\right) \cdot \frac{0}{0}}
\end{array}
Initial program 98.3%
lift--.f32N/A
sub-negN/A
lift-*.f32N/A
lower-fma.f32N/A
metadata-eval7.3
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 2024248
(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)))))