
(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 11 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 (/ (fma alpha alpha -1.0) (* (fma (* cosTheta (fma alpha alpha -1.0)) cosTheta 1.0) (log (pow (* alpha alpha) (PI))))))
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\mathsf{fma}\left(cosTheta \cdot \mathsf{fma}\left(\alpha, \alpha, -1\right), cosTheta, 1\right) \cdot \log \left({\left(\alpha \cdot \alpha\right)}^{\mathsf{PI}\left(\right)}\right)}
\end{array}
Initial program 98.5%
lift-/.f32N/A
frac-2negN/A
lower-/.f32N/A
lower-neg.f32N/A
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1-revN/A
lower-fma.f32N/A
lift-*.f32N/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f32N/A
Applied rewrites98.6%
Final simplification98.6%
(FPCore (cosTheta alpha) :precision binary32 (/ (/ (fma alpha alpha -1.0) (fma (* (fma alpha alpha -1.0) cosTheta) cosTheta 1.0)) (* (* 2.0 (log alpha)) (PI))))
\begin{array}{l}
\\
\frac{\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\mathsf{fma}\left(\mathsf{fma}\left(\alpha, \alpha, -1\right) \cdot cosTheta, cosTheta, 1\right)}}{\left(2 \cdot \log \alpha\right) \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 98.5%
lift-/.f32N/A
frac-2negN/A
lower-/.f32N/A
lower-neg.f32N/A
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1-revN/A
lower-fma.f32N/A
lift-*.f32N/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f32N/A
Applied rewrites98.6%
Applied rewrites98.5%
(FPCore (cosTheta alpha)
:precision binary32
(/
(fma alpha alpha -1.0)
(*
(*
(* -2.0 (fma (* (fma alpha alpha -1.0) cosTheta) (- cosTheta) -1.0))
(log alpha))
(PI))))\begin{array}{l}
\\
\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\left(\left(-2 \cdot \mathsf{fma}\left(\mathsf{fma}\left(\alpha, \alpha, -1\right) \cdot cosTheta, -cosTheta, -1\right)\right) \cdot \log \alpha\right) \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 98.5%
lift-/.f32N/A
frac-2negN/A
lower-/.f32N/A
lower-neg.f32N/A
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1-revN/A
lower-fma.f32N/A
lift-*.f32N/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f32N/A
Applied rewrites98.6%
Applied rewrites98.5%
lift-/.f32N/A
frac-2negN/A
distribute-frac-neg2N/A
lift-/.f32N/A
distribute-neg-frac2N/A
lift-fma.f32N/A
distribute-neg-inN/A
*-commutativeN/A
distribute-lft-neg-outN/A
lift-neg.f32N/A
metadata-evalN/A
lift-fma.f32N/A
associate-/r*N/A
Applied rewrites98.5%
lift-*.f32N/A
lift-*.f32N/A
associate-*r*N/A
lift-*.f32N/A
*-commutativeN/A
associate-*r*N/A
lower-*.f32N/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f3298.5
lift-fma.f32N/A
*-commutativeN/A
lower-fma.f3298.5
lift-*.f32N/A
*-commutativeN/A
lower-*.f3298.5
Applied rewrites98.5%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (* (PI) (log (* alpha alpha))) (fma (* cosTheta (fma alpha alpha -1.0)) cosTheta 1.0))))
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{\left(\mathsf{PI}\left(\right) \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \mathsf{fma}\left(cosTheta \cdot \mathsf{fma}\left(\alpha, \alpha, -1\right), cosTheta, 1\right)}
\end{array}
Initial program 98.5%
lift-+.f32N/A
+-commutativeN/A
lift-*.f32N/A
lower-fma.f3298.5
lift-*.f32N/A
*-commutativeN/A
lower-*.f3298.5
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1-revN/A
lower-fma.f3298.5
Applied rewrites98.5%
(FPCore (cosTheta alpha) :precision binary32 (/ (fma alpha alpha -1.0) (* (* (fma (* (fma alpha alpha -1.0) cosTheta) cosTheta 1.0) (PI)) (* 2.0 (log alpha)))))
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\left(\mathsf{fma}\left(\mathsf{fma}\left(\alpha, \alpha, -1\right) \cdot cosTheta, cosTheta, 1\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \left(2 \cdot \log \alpha\right)}
\end{array}
Initial program 98.5%
lift-/.f32N/A
frac-2negN/A
lower-/.f32N/A
lower-neg.f32N/A
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1-revN/A
lower-fma.f32N/A
lift-*.f32N/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f32N/A
Applied rewrites98.6%
Applied rewrites98.5%
(FPCore (cosTheta alpha) :precision binary32 (/ (fma alpha alpha -1.0) (* (* (fma (* cosTheta (fma alpha alpha -1.0)) cosTheta 1.0) (PI)) (log (* alpha alpha)))))
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\left(\mathsf{fma}\left(cosTheta \cdot \mathsf{fma}\left(\alpha, \alpha, -1\right), cosTheta, 1\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \log \left(\alpha \cdot \alpha\right)}
\end{array}
Initial program 98.5%
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1-revN/A
lower-fma.f3298.4
lift-*.f32N/A
*-commutativeN/A
lift-*.f32N/A
associate-*r*N/A
lower-*.f32N/A
Applied rewrites98.4%
(FPCore (cosTheta alpha) :precision binary32 (/ (/ (fma alpha alpha -1.0) (fma (- cosTheta) cosTheta 1.0)) (* (* 2.0 (log alpha)) (PI))))
\begin{array}{l}
\\
\frac{\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\mathsf{fma}\left(-cosTheta, cosTheta, 1\right)}}{\left(2 \cdot \log \alpha\right) \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 98.5%
lift-/.f32N/A
frac-2negN/A
lower-/.f32N/A
lower-neg.f32N/A
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1-revN/A
lower-fma.f32N/A
lift-*.f32N/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f32N/A
Applied rewrites98.6%
Applied rewrites98.5%
Taylor expanded in alpha around 0
mul-1-negN/A
lower-neg.f3297.3
Applied rewrites97.3%
(FPCore (cosTheta alpha) :precision binary32 (/ (fma alpha alpha -1.0) (* (fma (- cosTheta) (- cosTheta) -1.0) (* -2.0 (* (PI) (log alpha))))))
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\mathsf{fma}\left(-cosTheta, -cosTheta, -1\right) \cdot \left(-2 \cdot \left(\mathsf{PI}\left(\right) \cdot \log \alpha\right)\right)}
\end{array}
Initial program 98.5%
lift-/.f32N/A
frac-2negN/A
lower-/.f32N/A
lower-neg.f32N/A
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1-revN/A
lower-fma.f32N/A
lift-*.f32N/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f32N/A
Applied rewrites98.6%
Applied rewrites98.5%
lift-/.f32N/A
frac-2negN/A
distribute-frac-neg2N/A
lift-/.f32N/A
distribute-neg-frac2N/A
lift-fma.f32N/A
distribute-neg-inN/A
*-commutativeN/A
distribute-lft-neg-outN/A
lift-neg.f32N/A
metadata-evalN/A
lift-fma.f32N/A
associate-/r*N/A
Applied rewrites98.5%
Taylor expanded in alpha around 0
mul-1-negN/A
lower-neg.f3297.3
Applied rewrites97.3%
Final simplification97.3%
(FPCore (cosTheta alpha) :precision binary32 (/ (fma alpha alpha -1.0) (* (- (* cosTheta cosTheta) 1.0) (* -2.0 (* (PI) (log alpha))))))
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\left(cosTheta \cdot cosTheta - 1\right) \cdot \left(-2 \cdot \left(\mathsf{PI}\left(\right) \cdot \log \alpha\right)\right)}
\end{array}
Initial program 98.5%
lift-/.f32N/A
frac-2negN/A
lower-/.f32N/A
lower-neg.f32N/A
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1-revN/A
lower-fma.f32N/A
lift-*.f32N/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f32N/A
Applied rewrites98.6%
Applied rewrites98.5%
lift-/.f32N/A
frac-2negN/A
distribute-frac-neg2N/A
lift-/.f32N/A
distribute-neg-frac2N/A
lift-fma.f32N/A
distribute-neg-inN/A
*-commutativeN/A
distribute-lft-neg-outN/A
lift-neg.f32N/A
metadata-evalN/A
lift-fma.f32N/A
associate-/r*N/A
Applied rewrites98.5%
Taylor expanded in alpha around 0
lower--.f32N/A
unpow2N/A
lower-*.f3297.3
Applied rewrites97.3%
(FPCore (cosTheta alpha) :precision binary32 (/ (fma alpha alpha -1.0) (* (* 2.0 (log alpha)) (PI))))
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(\alpha, \alpha, -1\right)}{\left(2 \cdot \log \alpha\right) \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 98.5%
lift-/.f32N/A
frac-2negN/A
lower-/.f32N/A
lower-neg.f32N/A
lift--.f32N/A
lift-*.f32N/A
difference-of-sqr-1N/A
difference-of-sqr--1-revN/A
lower-fma.f32N/A
lift-*.f32N/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower-*.f32N/A
Applied rewrites98.6%
Applied rewrites98.5%
Taylor expanded in cosTheta around 0
unpow2N/A
difference-of-sqr-1-revN/A
difference-of-sqr--1-revN/A
lower-fma.f3295.8
Applied rewrites95.8%
(FPCore (cosTheta alpha) :precision binary32 (/ -1.0 (* (log (* alpha alpha)) (PI))))
\begin{array}{l}
\\
\frac{-1}{\log \left(\alpha \cdot \alpha\right) \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 98.5%
Taylor expanded in alpha around 0
Applied rewrites68.8%
Taylor expanded in cosTheta around 0
Applied rewrites67.7%
Taylor expanded in cosTheta around 0
*-commutativeN/A
lower-*.f32N/A
lower-log.f32N/A
unpow2N/A
lower-*.f32N/A
lower-PI.f3267.7
Applied rewrites67.7%
herbie shell --seed 2025010
(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)))))