
(FPCore (ux uy maxCos) :precision binary32 (let* ((t_0 (+ (- 1.0 ux) (* ux maxCos)))) (* (sin (* (* uy 2.0) (PI))) (sqrt (- 1.0 (* t_0 t_0))))))
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) + ux \cdot maxCos\\
\sin \left(\left(uy \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{1 - t\_0 \cdot t\_0}
\end{array}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 15 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (ux uy maxCos) :precision binary32 (let* ((t_0 (+ (- 1.0 ux) (* ux maxCos)))) (* (sin (* (* uy 2.0) (PI))) (sqrt (- 1.0 (* t_0 t_0))))))
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) + ux \cdot maxCos\\
\sin \left(\left(uy \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{1 - t\_0 \cdot t\_0}
\end{array}
\end{array}
(FPCore (ux uy maxCos)
:precision binary32
(let* ((t_0 (fma (- maxCos 2.0) (- maxCos) -1.0)))
(*
(sin (* (* uy 2.0) (PI)))
(sqrt
(*
(/
(- (pow (fma -2.0 maxCos (* ux t_0)) 2.0) 4.0)
(fma -2.0 maxCos (fma ux t_0 -2.0)))
ux)))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(maxCos - 2, -maxCos, -1\right)\\
\sin \left(\left(uy \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\frac{{\left(\mathsf{fma}\left(-2, maxCos, ux \cdot t\_0\right)\right)}^{2} - 4}{\mathsf{fma}\left(-2, maxCos, \mathsf{fma}\left(ux, t\_0, -2\right)\right)} \cdot ux}
\end{array}
\end{array}
Initial program 58.2%
Taylor expanded in ux around 0
*-commutativeN/A
lower-*.f32N/A
fp-cancel-sub-sign-invN/A
metadata-evalN/A
+-commutativeN/A
lower-fma.f32N/A
associate-*r*N/A
mul-1-negN/A
fp-cancel-sub-signN/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-pow.f32N/A
lower--.f3298.2
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites98.1%
Taylor expanded in ux around 0
Applied rewrites98.2%
Applied rewrites98.3%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sin (* (* uy 2.0) (PI)))
(sqrt
(*
(- (fma (- (+ (* maxCos (- maxCos 2.0)) 1.0)) ux (* -2.0 maxCos)) -2.0)
ux))))\begin{array}{l}
\\
\sin \left(\left(uy \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\left(\mathsf{fma}\left(-\left(maxCos \cdot \left(maxCos - 2\right) + 1\right), ux, -2 \cdot maxCos\right) - -2\right) \cdot ux}
\end{array}
Initial program 58.2%
Taylor expanded in ux around 0
*-commutativeN/A
lower-*.f32N/A
fp-cancel-sub-sign-invN/A
metadata-evalN/A
+-commutativeN/A
lower-fma.f32N/A
associate-*r*N/A
mul-1-negN/A
fp-cancel-sub-signN/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-pow.f32N/A
lower--.f3298.2
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites98.1%
Taylor expanded in ux around 0
Applied rewrites98.2%
Final simplification98.2%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sin (* (* uy 2.0) (PI)))
(sqrt
(*
(fma (fma (- maxCos 2.0) (- maxCos) -1.0) ux (- (* -2.0 maxCos) -2.0))
ux))))\begin{array}{l}
\\
\sin \left(\left(uy \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(\mathsf{fma}\left(maxCos - 2, -maxCos, -1\right), ux, -2 \cdot maxCos - -2\right) \cdot ux}
\end{array}
Initial program 58.2%
Taylor expanded in ux around 0
*-commutativeN/A
lower-*.f32N/A
fp-cancel-sub-sign-invN/A
metadata-evalN/A
+-commutativeN/A
lower-fma.f32N/A
associate-*r*N/A
mul-1-negN/A
fp-cancel-sub-signN/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-pow.f32N/A
lower--.f3298.2
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites98.1%
Taylor expanded in ux around 0
Applied rewrites98.2%
Applied rewrites98.2%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* (* uy 2.0) (PI))) (sqrt (fma (- 2.0 ux) ux (* (* (fma (- 2.0 maxCos) ux -2.0) ux) maxCos)))))
\begin{array}{l}
\\
\sin \left(\left(uy \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(2 - ux, ux, \left(\mathsf{fma}\left(2 - maxCos, ux, -2\right) \cdot ux\right) \cdot maxCos\right)}
\end{array}
Initial program 58.2%
Taylor expanded in ux around 0
*-commutativeN/A
lower-*.f32N/A
fp-cancel-sub-sign-invN/A
metadata-evalN/A
+-commutativeN/A
lower-fma.f32N/A
associate-*r*N/A
mul-1-negN/A
fp-cancel-sub-signN/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-pow.f32N/A
lower--.f3298.2
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites98.1%
Taylor expanded in ux around 0
Applied rewrites98.1%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* (* uy 2.0) (PI))) (sqrt (* (- (fma (- (* 2.0 maxCos) 1.0) ux (* -2.0 maxCos)) -2.0) ux))))
\begin{array}{l}
\\
\sin \left(\left(uy \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\left(\mathsf{fma}\left(2 \cdot maxCos - 1, ux, -2 \cdot maxCos\right) - -2\right) \cdot ux}
\end{array}
Initial program 58.2%
Taylor expanded in ux around 0
*-commutativeN/A
lower-*.f32N/A
fp-cancel-sub-sign-invN/A
metadata-evalN/A
+-commutativeN/A
lower-fma.f32N/A
associate-*r*N/A
mul-1-negN/A
fp-cancel-sub-signN/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-pow.f32N/A
lower--.f3298.2
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites98.1%
Taylor expanded in ux around 0
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites97.5%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* (* uy 2.0) (PI))) (sqrt (* (- (fma (fma 2.0 ux -2.0) maxCos (- ux)) -2.0) ux))))
\begin{array}{l}
\\
\sin \left(\left(uy \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\left(\mathsf{fma}\left(\mathsf{fma}\left(2, ux, -2\right), maxCos, -ux\right) - -2\right) \cdot ux}
\end{array}
Initial program 58.2%
Taylor expanded in ux around 0
*-commutativeN/A
lower-*.f32N/A
fp-cancel-sub-sign-invN/A
metadata-evalN/A
+-commutativeN/A
lower-fma.f32N/A
associate-*r*N/A
mul-1-negN/A
fp-cancel-sub-signN/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-pow.f32N/A
lower--.f3298.2
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites98.1%
Taylor expanded in ux around 0
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites97.4%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* (* uy 2.0) (PI))) (sqrt (* (- (fma -1.0 ux (* -2.0 maxCos)) -2.0) ux))))
\begin{array}{l}
\\
\sin \left(\left(uy \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\left(\mathsf{fma}\left(-1, ux, -2 \cdot maxCos\right) - -2\right) \cdot ux}
\end{array}
Initial program 58.2%
Taylor expanded in ux around 0
*-commutativeN/A
lower-*.f32N/A
fp-cancel-sub-sign-invN/A
metadata-evalN/A
+-commutativeN/A
lower-fma.f32N/A
associate-*r*N/A
mul-1-negN/A
fp-cancel-sub-signN/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-pow.f32N/A
lower--.f3298.2
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites98.1%
Taylor expanded in ux around 0
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites96.9%
(FPCore (ux uy maxCos)
:precision binary32
(let* ((t_0 (sin (* (* uy 2.0) (PI)))))
(if (<= maxCos 0.0001500000071246177)
(* t_0 (sqrt (* (- 2.0 ux) ux)))
(* t_0 (sqrt (* (fma -2.0 maxCos 2.0) ux))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sin \left(\left(uy \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right)\\
\mathbf{if}\;maxCos \leq 0.0001500000071246177:\\
\;\;\;\;t\_0 \cdot \sqrt{\left(2 - ux\right) \cdot ux}\\
\mathbf{else}:\\
\;\;\;\;t\_0 \cdot \sqrt{\mathsf{fma}\left(-2, maxCos, 2\right) \cdot ux}\\
\end{array}
\end{array}
if maxCos < 1.50000007e-4Initial program 59.5%
Taylor expanded in ux around 0
*-commutativeN/A
lower-*.f32N/A
fp-cancel-sub-sign-invN/A
metadata-evalN/A
+-commutativeN/A
lower-fma.f32N/A
associate-*r*N/A
mul-1-negN/A
fp-cancel-sub-signN/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-pow.f32N/A
lower--.f3298.2
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites97.4%
if 1.50000007e-4 < maxCos Initial program 44.5%
Taylor expanded in ux around 0
metadata-evalN/A
fp-cancel-sign-sub-invN/A
*-commutativeN/A
lower-*.f32N/A
+-commutativeN/A
lower-fma.f3283.1
Applied rewrites83.1%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* (* uy 2.0) (PI))) (sqrt (* (- 2.0 ux) ux))))
\begin{array}{l}
\\
\sin \left(\left(uy \cdot 2\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\left(2 - ux\right) \cdot ux}
\end{array}
Initial program 58.2%
Taylor expanded in ux around 0
*-commutativeN/A
lower-*.f32N/A
fp-cancel-sub-sign-invN/A
metadata-evalN/A
+-commutativeN/A
lower-fma.f32N/A
associate-*r*N/A
mul-1-negN/A
fp-cancel-sub-signN/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-pow.f32N/A
lower--.f3298.2
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites92.9%
(FPCore (ux uy maxCos)
:precision binary32
(let* ((t_0 (+ (- 1.0 ux) (* ux maxCos))))
(if (<= (sqrt (- 1.0 (* t_0 t_0))) 0.014999999664723873)
(* (* (+ (PI) (PI)) uy) (sqrt (* (fma -2.0 maxCos 2.0) ux)))
(* (* (* (PI) 2.0) uy) (sqrt (- 1.0 (* t_0 (- 1.0 ux))))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) + ux \cdot maxCos\\
\mathbf{if}\;\sqrt{1 - t\_0 \cdot t\_0} \leq 0.014999999664723873:\\
\;\;\;\;\left(\left(\mathsf{PI}\left(\right) + \mathsf{PI}\left(\right)\right) \cdot uy\right) \cdot \sqrt{\mathsf{fma}\left(-2, maxCos, 2\right) \cdot ux}\\
\mathbf{else}:\\
\;\;\;\;\left(\left(\mathsf{PI}\left(\right) \cdot 2\right) \cdot uy\right) \cdot \sqrt{1 - t\_0 \cdot \left(1 - ux\right)}\\
\end{array}
\end{array}
if (sqrt.f32 (-.f32 #s(literal 1 binary32) (*.f32 (+.f32 (-.f32 #s(literal 1 binary32) ux) (*.f32 ux maxCos)) (+.f32 (-.f32 #s(literal 1 binary32) ux) (*.f32 ux maxCos))))) < 0.0149999997Initial program 35.3%
Taylor expanded in uy around 0
*-commutativeN/A
associate-*r*N/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3232.4
Applied rewrites32.4%
Taylor expanded in ux around 0
metadata-evalN/A
fp-cancel-sign-sub-invN/A
*-commutativeN/A
lower-*.f32N/A
+-commutativeN/A
lower-fma.f3275.1
Applied rewrites75.1%
Applied rewrites75.1%
if 0.0149999997 < (sqrt.f32 (-.f32 #s(literal 1 binary32) (*.f32 (+.f32 (-.f32 #s(literal 1 binary32) ux) (*.f32 ux maxCos)) (+.f32 (-.f32 #s(literal 1 binary32) ux) (*.f32 ux maxCos))))) Initial program 88.6%
Taylor expanded in uy around 0
*-commutativeN/A
associate-*r*N/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3276.8
Applied rewrites76.8%
Taylor expanded in maxCos around 0
lower--.f3275.6
Applied rewrites75.6%
(FPCore (ux uy maxCos) :precision binary32 (* (* (+ (fma (* (* uy uy) -1.3333333333333333) (* (* (PI) (PI)) (PI)) (PI)) (PI)) uy) (sqrt (* (- (/ 2.0 ux) 1.0) (* ux ux)))))
\begin{array}{l}
\\
\left(\left(\mathsf{fma}\left(\left(uy \cdot uy\right) \cdot -1.3333333333333333, \left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \mathsf{PI}\left(\right), \mathsf{PI}\left(\right)\right) + \mathsf{PI}\left(\right)\right) \cdot uy\right) \cdot \sqrt{\left(\frac{2}{ux} - 1\right) \cdot \left(ux \cdot ux\right)}
\end{array}
Initial program 58.2%
Taylor expanded in ux around inf
*-commutativeN/A
lower-*.f32N/A
associate--r+N/A
associate-*r/N/A
metadata-evalN/A
associate-*r/N/A
div-subN/A
metadata-evalN/A
fp-cancel-sign-sub-invN/A
lower--.f32N/A
lower-/.f32N/A
+-commutativeN/A
lower-fma.f32N/A
lower-pow.f32N/A
lower--.f32N/A
unpow2N/A
lower-*.f3298.2
Applied rewrites98.2%
Taylor expanded in uy around 0
*-commutativeN/A
*-commutativeN/A
associate-*r*N/A
+-commutativeN/A
lower-*.f32N/A
Applied rewrites88.8%
Taylor expanded in maxCos around 0
Applied rewrites84.7%
Applied rewrites84.7%
(FPCore (ux uy maxCos)
:precision binary32
(*
(* (* (PI) uy) 2.0)
(sqrt
(*
(- (fma (- (+ (* maxCos (- maxCos 2.0)) 1.0)) ux (* -2.0 maxCos)) -2.0)
ux))))\begin{array}{l}
\\
\left(\left(\mathsf{PI}\left(\right) \cdot uy\right) \cdot 2\right) \cdot \sqrt{\left(\mathsf{fma}\left(-\left(maxCos \cdot \left(maxCos - 2\right) + 1\right), ux, -2 \cdot maxCos\right) - -2\right) \cdot ux}
\end{array}
Initial program 58.2%
Taylor expanded in ux around 0
*-commutativeN/A
lower-*.f32N/A
fp-cancel-sub-sign-invN/A
metadata-evalN/A
+-commutativeN/A
lower-fma.f32N/A
associate-*r*N/A
mul-1-negN/A
fp-cancel-sub-signN/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-pow.f32N/A
lower--.f3298.2
Applied rewrites98.2%
Taylor expanded in maxCos around 0
Applied rewrites98.1%
Taylor expanded in ux around 0
Applied rewrites98.2%
Taylor expanded in uy around 0
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3280.4
Applied rewrites80.4%
Final simplification80.4%
(FPCore (ux uy maxCos) :precision binary32 (* (* (* (PI) 2.0) uy) (sqrt (* (- (/ 2.0 ux) 1.0) (* ux ux)))))
\begin{array}{l}
\\
\left(\left(\mathsf{PI}\left(\right) \cdot 2\right) \cdot uy\right) \cdot \sqrt{\left(\frac{2}{ux} - 1\right) \cdot \left(ux \cdot ux\right)}
\end{array}
Initial program 58.2%
Taylor expanded in ux around inf
*-commutativeN/A
lower-*.f32N/A
associate--r+N/A
associate-*r/N/A
metadata-evalN/A
associate-*r/N/A
div-subN/A
metadata-evalN/A
fp-cancel-sign-sub-invN/A
lower--.f32N/A
lower-/.f32N/A
+-commutativeN/A
lower-fma.f32N/A
lower-pow.f32N/A
lower--.f32N/A
unpow2N/A
lower-*.f3298.2
Applied rewrites98.2%
Taylor expanded in uy around 0
*-commutativeN/A
*-commutativeN/A
associate-*r*N/A
+-commutativeN/A
lower-*.f32N/A
Applied rewrites88.8%
Taylor expanded in maxCos around 0
Applied rewrites84.7%
Taylor expanded in uy around 0
Applied rewrites77.2%
(FPCore (ux uy maxCos) :precision binary32 (* (* (+ (PI) (PI)) uy) (sqrt (* (fma -2.0 maxCos 2.0) ux))))
\begin{array}{l}
\\
\left(\left(\mathsf{PI}\left(\right) + \mathsf{PI}\left(\right)\right) \cdot uy\right) \cdot \sqrt{\mathsf{fma}\left(-2, maxCos, 2\right) \cdot ux}
\end{array}
Initial program 58.2%
Taylor expanded in uy around 0
*-commutativeN/A
associate-*r*N/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3251.5
Applied rewrites51.5%
Taylor expanded in ux around 0
metadata-evalN/A
fp-cancel-sign-sub-invN/A
*-commutativeN/A
lower-*.f32N/A
+-commutativeN/A
lower-fma.f3264.2
Applied rewrites64.2%
Applied rewrites64.2%
(FPCore (ux uy maxCos) :precision binary32 (* (+ uy uy) (sqrt (* (fma -2.0 maxCos 2.0) ux))))
float code(float ux, float uy, float maxCos) {
return (uy + uy) * sqrtf((fmaf(-2.0f, maxCos, 2.0f) * ux));
}
function code(ux, uy, maxCos) return Float32(Float32(uy + uy) * sqrt(Float32(fma(Float32(-2.0), maxCos, Float32(2.0)) * ux))) end
\begin{array}{l}
\\
\left(uy + uy\right) \cdot \sqrt{\mathsf{fma}\left(-2, maxCos, 2\right) \cdot ux}
\end{array}
Initial program 58.2%
Taylor expanded in uy around 0
*-commutativeN/A
associate-*r*N/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3251.5
Applied rewrites51.5%
Taylor expanded in ux around 0
metadata-evalN/A
fp-cancel-sign-sub-invN/A
*-commutativeN/A
lower-*.f32N/A
+-commutativeN/A
lower-fma.f3264.2
Applied rewrites64.2%
Applied rewrites64.2%
Applied rewrites25.5%
herbie shell --seed 2025008
(FPCore (ux uy maxCos)
:name "UniformSampleCone, y"
:precision binary32
:pre (and (and (and (<= 2.328306437e-10 ux) (<= ux 1.0)) (and (<= 2.328306437e-10 uy) (<= uy 1.0))) (and (<= 0.0 maxCos) (<= maxCos 1.0)))
(* (sin (* (* uy 2.0) (PI))) (sqrt (- 1.0 (* (+ (- 1.0 ux) (* ux maxCos)) (+ (- 1.0 ux) (* ux maxCos)))))))