
(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 14 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
(*
(log (pow (* alpha alpha) (PI)))
(+ 1.0 (* (* t_0 cosTheta) cosTheta))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t\_0}{\log \left({\left(\alpha \cdot \alpha\right)}^{\mathsf{PI}\left(\right)}\right) \cdot \left(1 + \left(t\_0 \cdot cosTheta\right) \cdot cosTheta\right)}
\end{array}
\end{array}
Initial program 98.6%
lift-PI.f32N/A
lift-*.f32N/A
lift-log.f32N/A
log-pow-revN/A
lift-*.f32N/A
pow2N/A
lower-log.f32N/A
lower-pow.f32N/A
pow2N/A
lift-*.f32N/A
lift-PI.f3298.6
Applied rewrites98.6%
(FPCore (cosTheta alpha)
:precision binary32
(/
(- (* alpha alpha) 1.0)
(*
(PI)
(*
(fma (* (fma alpha alpha -1.0) cosTheta) cosTheta 1.0)
(log (* alpha alpha))))))\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{\mathsf{PI}\left(\right) \cdot \left(\mathsf{fma}\left(\mathsf{fma}\left(\alpha, \alpha, -1\right) \cdot cosTheta, cosTheta, 1\right) \cdot \log \left(\alpha \cdot \alpha\right)\right)}
\end{array}
Initial program 98.6%
lift-*.f32N/A
lift-PI.f32N/A
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
pow2N/A
lift-+.f32N/A
lift-*.f32N/A
lift-*.f32N/A
lift--.f32N/A
lift-*.f32N/A
associate-*l*N/A
lower-*.f32N/A
lift-PI.f32N/A
lower-*.f32N/A
Applied rewrites98.6%
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
pow2N/A
lift-fma.f32N/A
lift-*.f32N/A
lift--.f32N/A
lift-*.f32N/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
*-commutativeN/A
+-commutativeN/A
lower-*.f32N/A
Applied rewrites98.6%
(FPCore (cosTheta alpha)
:precision binary32
(/
(fma alpha alpha -1.0)
(*
(PI)
(*
(fma (* (fma alpha alpha -1.0) cosTheta) cosTheta 1.0)
(log (* alpha alpha))))))\begin{array}{l}
\\
\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\mathsf{PI}\left(\right) \cdot \left(\mathsf{fma}\left(\mathsf{fma}\left(\alpha, \alpha, -1\right) \cdot cosTheta, cosTheta, 1\right) \cdot \log \left(\alpha \cdot \alpha\right)\right)}
\end{array}
Initial program 98.6%
lift-*.f32N/A
lift-PI.f32N/A
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
pow2N/A
lift-+.f32N/A
lift-*.f32N/A
lift-*.f32N/A
lift--.f32N/A
lift-*.f32N/A
associate-*l*N/A
lower-*.f32N/A
lift-PI.f32N/A
lower-*.f32N/A
Applied rewrites98.6%
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
pow2N/A
lift-fma.f32N/A
lift-*.f32N/A
lift--.f32N/A
lift-*.f32N/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
*-commutativeN/A
+-commutativeN/A
lower-*.f32N/A
Applied rewrites98.6%
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1N/A
lift-fma.f3298.5
Applied rewrites98.5%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (PI) (* (fma (- cosTheta) cosTheta 1.0) (log (* alpha alpha))))))
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{\mathsf{PI}\left(\right) \cdot \left(\mathsf{fma}\left(-cosTheta, cosTheta, 1\right) \cdot \log \left(\alpha \cdot \alpha\right)\right)}
\end{array}
Initial program 98.6%
lift-*.f32N/A
lift-PI.f32N/A
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
pow2N/A
lift-+.f32N/A
lift-*.f32N/A
lift-*.f32N/A
lift--.f32N/A
lift-*.f32N/A
associate-*l*N/A
lower-*.f32N/A
lift-PI.f32N/A
lower-*.f32N/A
Applied rewrites98.6%
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
pow2N/A
lift-fma.f32N/A
lift-*.f32N/A
lift--.f32N/A
lift-*.f32N/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
*-commutativeN/A
+-commutativeN/A
lower-*.f32N/A
Applied rewrites98.6%
Taylor expanded in alpha around 0
mul-1-negN/A
lower-neg.f3297.6
Applied rewrites97.6%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (* 2.0 (PI)) (* (fma cosTheta (- cosTheta) 1.0) (log alpha)))))
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(\mathsf{fma}\left(cosTheta, -cosTheta, 1\right) \cdot \log \alpha\right)}
\end{array}
Initial program 98.6%
lift-*.f32N/A
lift-PI.f32N/A
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
pow2N/A
lift-+.f32N/A
lift-*.f32N/A
lift-*.f32N/A
lift--.f32N/A
lift-*.f32N/A
associate-*l*N/A
lower-*.f32N/A
lift-PI.f32N/A
lower-*.f32N/A
Applied rewrites98.6%
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
pow2N/A
lift-fma.f32N/A
lift-*.f32N/A
lift--.f32N/A
lift-*.f32N/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
*-commutativeN/A
+-commutativeN/A
lower-*.f32N/A
Applied rewrites98.6%
Taylor expanded in alpha around 0
associate-*r*N/A
lower-*.f32N/A
lower-*.f32N/A
lift-PI.f32N/A
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
pow2N/A
+-commutativeN/A
associate-*l*N/A
*-commutativeN/A
lower-fma.f32N/A
mul-1-negN/A
lower-neg.f32N/A
lift-log.f3297.5
Applied rewrites97.5%
(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
pow2N/A
lift-*.f32N/A
lift--.f32N/A
lift-PI.f32N/A
lower-log.f32N/A
pow2N/A
lift-*.f3295.7
Applied rewrites95.7%
(FPCore (cosTheta alpha) :precision binary32 (* 0.5 (/ (/ (fma alpha alpha -1.0) (PI)) (log alpha))))
\begin{array}{l}
\\
0.5 \cdot \frac{\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\mathsf{PI}\left(\right)}}{\log \alpha}
\end{array}
Initial program 98.6%
lift--.f32N/A
lift-*.f32N/A
pow2N/A
flip--N/A
lower-/.f32N/A
metadata-evalN/A
lower--.f32N/A
pow-prod-upN/A
metadata-evalN/A
lower-pow.f32N/A
pow2N/A
lower-fma.f3298.3
Applied rewrites98.3%
Taylor expanded in cosTheta around 0
metadata-evalN/A
pow-prod-upN/A
metadata-evalN/A
pow2N/A
flip--N/A
pow2N/A
associate-/r*N/A
lower-/.f32N/A
lower-/.f32N/A
lift-pow.f32N/A
lift--.f32N/A
lift-PI.f32N/A
*-commutativeN/A
Applied rewrites95.3%
Taylor expanded in alpha around 0
distribute-lft-out--N/A
lower-*.f32N/A
associate-/r*N/A
associate-/r*N/A
sub-divN/A
sub-divN/A
pow2N/A
lower-/.f32N/A
lower-/.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1N/A
lift-fma.f32N/A
lift-PI.f32N/A
lift-log.f3295.7
Applied rewrites95.7%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (PI) (log (* alpha alpha)))))
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{\mathsf{PI}\left(\right) \cdot \log \left(\alpha \cdot \alpha\right)}
\end{array}
Initial program 98.6%
lift-*.f32N/A
lift-PI.f32N/A
lift-*.f32N/A
lift-log.f32N/A
lift-*.f32N/A
pow2N/A
lift-+.f32N/A
lift-*.f32N/A
lift-*.f32N/A
lift--.f32N/A
lift-*.f32N/A
associate-*l*N/A
lower-*.f32N/A
lift-PI.f32N/A
lower-*.f32N/A
Applied rewrites98.6%
Taylor expanded in cosTheta around 0
lower-log.f32N/A
pow2N/A
lift-*.f3295.7
Applied rewrites95.7%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (* 2.0 (PI)) (log alpha))))
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot \log \alpha}
\end{array}
Initial program 98.6%
lift-PI.f32N/A
lift-*.f32N/A
lift-log.f32N/A
log-pow-revN/A
lift-*.f32N/A
pow2N/A
lower-log.f32N/A
lower-pow.f32N/A
pow2N/A
lift-*.f32N/A
lift-PI.f3298.6
Applied rewrites98.6%
Taylor expanded in cosTheta around 0
log-pow-revN/A
pow-powN/A
log-pow-revN/A
lower-*.f32N/A
lower-*.f32N/A
lift-PI.f32N/A
lower-log.f3295.6
Applied rewrites95.6%
Final simplification95.6%
(FPCore (cosTheta alpha) :precision binary32 (/ -0.5 (* (* (log alpha) (PI)) (fma cosTheta (- cosTheta) 1.0))))
\begin{array}{l}
\\
\frac{-0.5}{\left(\log \alpha \cdot \mathsf{PI}\left(\right)\right) \cdot \mathsf{fma}\left(cosTheta, -cosTheta, 1\right)}
\end{array}
Initial program 98.6%
Taylor expanded in alpha around 0
associate-/r*N/A
lower-/.f32N/A
lower-/.f32N/A
lift-PI.f32N/A
*-commutativeN/A
log-pow-revN/A
lower-log.f32N/A
lower-pow.f32N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f32N/A
unpow2N/A
lower-*.f3265.8
Applied rewrites65.8%
lift-/.f32N/A
lift-PI.f32N/A
lift-/.f32N/A
lift-log.f32N/A
lift-pow.f32N/A
lift-*.f32N/A
lift-fma.f32N/A
log-powN/A
+-commutativeN/A
pow2N/A
*-commutativeN/A
*-commutativeN/A
associate-/r*N/A
lower-/.f32N/A
associate-*r*N/A
lower-*.f32N/A
Applied rewrites65.8%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* -0.5 (* cosTheta cosTheta)) 0.5) (* (log alpha) (PI))))
\begin{array}{l}
\\
\frac{-0.5 \cdot \left(cosTheta \cdot cosTheta\right) - 0.5}{\log \alpha \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 98.6%
Taylor expanded in alpha around 0
associate-/r*N/A
lower-/.f32N/A
lower-/.f32N/A
lift-PI.f32N/A
*-commutativeN/A
log-pow-revN/A
lower-log.f32N/A
lower-pow.f32N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f32N/A
unpow2N/A
lower-*.f3265.8
Applied rewrites65.8%
Taylor expanded in cosTheta around 0
lower-/.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-log.f32N/A
lift-PI.f3265.2
Applied rewrites65.2%
Taylor expanded in cosTheta around 0
associate-*r/N/A
associate-*r/N/A
metadata-evalN/A
sub-divN/A
lower-/.f32N/A
lower--.f32N/A
lower-*.f32N/A
pow2N/A
lift-*.f32N/A
*-commutativeN/A
lift-log.f32N/A
lift-*.f32N/A
lift-PI.f3265.7
Applied rewrites65.7%
(FPCore (cosTheta alpha) :precision binary32 (/ (/ -0.5 (PI)) (log alpha)))
\begin{array}{l}
\\
\frac{\frac{-0.5}{\mathsf{PI}\left(\right)}}{\log \alpha}
\end{array}
Initial program 98.6%
Taylor expanded in alpha around 0
associate-/r*N/A
lower-/.f32N/A
lower-/.f32N/A
lift-PI.f32N/A
*-commutativeN/A
log-pow-revN/A
lower-log.f32N/A
lower-pow.f32N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f32N/A
unpow2N/A
lower-*.f3265.8
Applied rewrites65.8%
Taylor expanded in cosTheta around 0
Applied rewrites65.3%
(FPCore (cosTheta alpha) :precision binary32 (/ (/ -0.5 (log alpha)) (PI)))
\begin{array}{l}
\\
\frac{\frac{-0.5}{\log \alpha}}{\mathsf{PI}\left(\right)}
\end{array}
Initial program 98.6%
Taylor expanded in alpha around 0
associate-/r*N/A
lower-/.f32N/A
lower-/.f32N/A
lift-PI.f32N/A
*-commutativeN/A
log-pow-revN/A
lower-log.f32N/A
lower-pow.f32N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f32N/A
unpow2N/A
lower-*.f3265.8
Applied rewrites65.8%
Taylor expanded in cosTheta around 0
lower-/.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-log.f32N/A
lift-PI.f3265.2
Applied rewrites65.2%
lift-/.f32N/A
lift-PI.f32N/A
lift-*.f32N/A
lift-log.f32N/A
associate-/r*N/A
lower-/.f32N/A
lower-/.f32N/A
lift-log.f32N/A
lift-PI.f3265.3
Applied rewrites65.3%
(FPCore (cosTheta alpha) :precision binary32 (/ -0.5 (* (log alpha) (PI))))
\begin{array}{l}
\\
\frac{-0.5}{\log \alpha \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 98.6%
Taylor expanded in alpha around 0
associate-/r*N/A
lower-/.f32N/A
lower-/.f32N/A
lift-PI.f32N/A
*-commutativeN/A
log-pow-revN/A
lower-log.f32N/A
lower-pow.f32N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f32N/A
unpow2N/A
lower-*.f3265.8
Applied rewrites65.8%
Taylor expanded in cosTheta around 0
lower-/.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-log.f32N/A
lift-PI.f3265.2
Applied rewrites65.2%
herbie shell --seed 2025037
(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)))))