
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* (* (- 1.0 ux) maxCos) ux))
(t_1 (sqrt (- 1.0 (* t_0 t_0))))
(t_2 (* (* uy 2.0) PI)))
(+ (+ (* (* (cos t_2) t_1) xi) (* (* (sin t_2) t_1) yi)) (* t_0 zi))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = ((1.0f - ux) * maxCos) * ux;
float t_1 = sqrtf((1.0f - (t_0 * t_0)));
float t_2 = (uy * 2.0f) * ((float) M_PI);
return (((cosf(t_2) * t_1) * xi) + ((sinf(t_2) * t_1) * yi)) + (t_0 * zi);
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(Float32(Float32(1.0) - ux) * maxCos) * ux) t_1 = sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0))) t_2 = Float32(Float32(uy * Float32(2.0)) * Float32(pi)) return Float32(Float32(Float32(Float32(cos(t_2) * t_1) * xi) + Float32(Float32(sin(t_2) * t_1) * yi)) + Float32(t_0 * zi)) end
function tmp = code(xi, yi, zi, ux, uy, maxCos) t_0 = ((single(1.0) - ux) * maxCos) * ux; t_1 = sqrt((single(1.0) - (t_0 * t_0))); t_2 = (uy * single(2.0)) * single(pi); tmp = (((cos(t_2) * t_1) * xi) + ((sin(t_2) * t_1) * yi)) + (t_0 * zi); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(\left(1 - ux\right) \cdot maxCos\right) \cdot ux\\
t_1 := \sqrt{1 - t\_0 \cdot t\_0}\\
t_2 := \left(uy \cdot 2\right) \cdot \pi\\
\left(\left(\cos t\_2 \cdot t\_1\right) \cdot xi + \left(\sin t\_2 \cdot t\_1\right) \cdot yi\right) + t\_0 \cdot zi
\end{array}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 7 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* (* (- 1.0 ux) maxCos) ux))
(t_1 (sqrt (- 1.0 (* t_0 t_0))))
(t_2 (* (* uy 2.0) PI)))
(+ (+ (* (* (cos t_2) t_1) xi) (* (* (sin t_2) t_1) yi)) (* t_0 zi))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = ((1.0f - ux) * maxCos) * ux;
float t_1 = sqrtf((1.0f - (t_0 * t_0)));
float t_2 = (uy * 2.0f) * ((float) M_PI);
return (((cosf(t_2) * t_1) * xi) + ((sinf(t_2) * t_1) * yi)) + (t_0 * zi);
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(Float32(Float32(1.0) - ux) * maxCos) * ux) t_1 = sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0))) t_2 = Float32(Float32(uy * Float32(2.0)) * Float32(pi)) return Float32(Float32(Float32(Float32(cos(t_2) * t_1) * xi) + Float32(Float32(sin(t_2) * t_1) * yi)) + Float32(t_0 * zi)) end
function tmp = code(xi, yi, zi, ux, uy, maxCos) t_0 = ((single(1.0) - ux) * maxCos) * ux; t_1 = sqrt((single(1.0) - (t_0 * t_0))); t_2 = (uy * single(2.0)) * single(pi); tmp = (((cos(t_2) * t_1) * xi) + ((sin(t_2) * t_1) * yi)) + (t_0 * zi); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(\left(1 - ux\right) \cdot maxCos\right) \cdot ux\\
t_1 := \sqrt{1 - t\_0 \cdot t\_0}\\
t_2 := \left(uy \cdot 2\right) \cdot \pi\\
\left(\left(\cos t\_2 \cdot t\_1\right) \cdot xi + \left(\sin t\_2 \cdot t\_1\right) \cdot yi\right) + t\_0 \cdot zi
\end{array}
\end{array}
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi) (+ (* maxCos (- (* ux zi) (* ux (* ux zi)))) (* yi (sin (* 2.0 (* uy PI)))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(cosf((uy * (2.0f * ((float) M_PI)))), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), ((maxCos * ((ux * zi) - (ux * (ux * zi)))) + (yi * sinf((2.0f * (uy * ((float) M_PI)))))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), Float32(Float32(maxCos * Float32(Float32(ux * zi) - Float32(ux * Float32(ux * zi)))) + Float32(yi * sin(Float32(Float32(2.0) * Float32(uy * Float32(pi))))))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, maxCos \cdot \left(ux \cdot zi - ux \cdot \left(ux \cdot zi\right)\right) + yi \cdot \sin \left(2 \cdot \left(uy \cdot \pi\right)\right)\right)
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in maxCos around 0 99.1%
Taylor expanded in ux around 0 99.1%
Taylor expanded in ux around 0 99.1%
associate-*r*99.1%
sub-neg99.1%
distribute-rgt-in99.1%
*-un-lft-identity99.1%
Applied egg-rr99.1%
Final simplification99.1%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi) (+ (* yi (sin (* 2.0 (* uy PI)))) (* maxCos (* ux (* zi (- 1.0 ux)))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(cosf((uy * (2.0f * ((float) M_PI)))), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), ((yi * sinf((2.0f * (uy * ((float) M_PI))))) + (maxCos * (ux * (zi * (1.0f - ux))))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), Float32(Float32(yi * sin(Float32(Float32(2.0) * Float32(uy * Float32(pi))))) + Float32(maxCos * Float32(ux * Float32(zi * Float32(Float32(1.0) - ux)))))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, yi \cdot \sin \left(2 \cdot \left(uy \cdot \pi\right)\right) + maxCos \cdot \left(ux \cdot \left(zi \cdot \left(1 - ux\right)\right)\right)\right)
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in maxCos around 0 99.1%
Taylor expanded in ux around 0 99.1%
Taylor expanded in ux around 0 99.1%
Final simplification99.1%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* ux (* maxCos (- 1.0 ux)))))
(+
(+
(* yi (sin (* 2.0 (* uy PI))))
(*
xi
(*
(cos (* PI (* uy 2.0)))
(sqrt (+ 1.0 (* t_0 (* ux (* maxCos (+ ux -1.0)))))))))
(* zi t_0))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = ux * (maxCos * (1.0f - ux));
return ((yi * sinf((2.0f * (uy * ((float) M_PI))))) + (xi * (cosf((((float) M_PI) * (uy * 2.0f))) * sqrtf((1.0f + (t_0 * (ux * (maxCos * (ux + -1.0f))))))))) + (zi * t_0);
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(ux * Float32(maxCos * Float32(Float32(1.0) - ux))) return Float32(Float32(Float32(yi * sin(Float32(Float32(2.0) * Float32(uy * Float32(pi))))) + Float32(xi * Float32(cos(Float32(Float32(pi) * Float32(uy * Float32(2.0)))) * sqrt(Float32(Float32(1.0) + Float32(t_0 * Float32(ux * Float32(maxCos * Float32(ux + Float32(-1.0)))))))))) + Float32(zi * t_0)) end
function tmp = code(xi, yi, zi, ux, uy, maxCos) t_0 = ux * (maxCos * (single(1.0) - ux)); tmp = ((yi * sin((single(2.0) * (uy * single(pi))))) + (xi * (cos((single(pi) * (uy * single(2.0)))) * sqrt((single(1.0) + (t_0 * (ux * (maxCos * (ux + single(-1.0)))))))))) + (zi * t_0); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := ux \cdot \left(maxCos \cdot \left(1 - ux\right)\right)\\
\left(yi \cdot \sin \left(2 \cdot \left(uy \cdot \pi\right)\right) + xi \cdot \left(\cos \left(\pi \cdot \left(uy \cdot 2\right)\right) \cdot \sqrt{1 + t\_0 \cdot \left(ux \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\right)}\right)\right) + zi \cdot t\_0
\end{array}
\end{array}
Initial program 99.0%
Taylor expanded in ux around 0 99.0%
Final simplification99.0%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi) (+ (* maxCos (* ux (* zi (- 1.0 ux)))) (* (* uy 2.0) (* PI yi)))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(cosf((uy * (2.0f * ((float) M_PI)))), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), ((maxCos * (ux * (zi * (1.0f - ux)))) + ((uy * 2.0f) * (((float) M_PI) * yi))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), Float32(Float32(maxCos * Float32(ux * Float32(zi * Float32(Float32(1.0) - ux)))) + Float32(Float32(uy * Float32(2.0)) * Float32(Float32(pi) * yi)))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, maxCos \cdot \left(ux \cdot \left(zi \cdot \left(1 - ux\right)\right)\right) + \left(uy \cdot 2\right) \cdot \left(\pi \cdot yi\right)\right)
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in maxCos around 0 99.1%
Taylor expanded in ux around 0 99.1%
Taylor expanded in ux around 0 99.1%
Taylor expanded in uy around 0 91.5%
associate-*r*91.5%
*-commutative91.5%
*-commutative91.5%
*-commutative91.5%
*-commutative91.5%
Simplified91.5%
Final simplification91.5%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi) (* maxCos (* ux (* zi (- 1.0 ux))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(cosf((uy * (2.0f * ((float) M_PI)))), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), (maxCos * (ux * (zi * (1.0f - ux)))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), Float32(maxCos * Float32(ux * Float32(zi * Float32(Float32(1.0) - ux))))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, maxCos \cdot \left(ux \cdot \left(zi \cdot \left(1 - ux\right)\right)\right)\right)
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in uy around 0 59.5%
*-commutative59.5%
Simplified59.5%
Taylor expanded in ux around 0 59.5%
Taylor expanded in ux around 0 59.5%
Final simplification59.5%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi) (* maxCos (* (* ux zi) (- 1.0 ux)))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(cosf((uy * (2.0f * ((float) M_PI)))), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), (maxCos * ((ux * zi) * (1.0f - ux))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), Float32(maxCos * Float32(Float32(ux * zi) * Float32(Float32(1.0) - ux)))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, maxCos \cdot \left(\left(ux \cdot zi\right) \cdot \left(1 - ux\right)\right)\right)
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in uy around 0 59.5%
*-commutative59.5%
Simplified59.5%
Taylor expanded in ux around 0 59.5%
Taylor expanded in ux around 0 59.5%
Taylor expanded in ux around 0 59.4%
distribute-lft-in59.5%
*-lft-identity59.5%
mul-1-neg59.5%
distribute-rgt-neg-out59.5%
distribute-lft-neg-in59.5%
distribute-rgt-in59.5%
sub-neg59.5%
*-commutative59.5%
Simplified59.5%
Final simplification59.5%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma (cos (* uy (* 2.0 PI))) (* (sqrt (- 1.0 (* (* maxCos ux) (* maxCos ux)))) xi) (* maxCos (* ux zi))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(cosf((uy * (2.0f * ((float) M_PI)))), (sqrtf((1.0f - ((maxCos * ux) * (maxCos * ux)))) * xi), (maxCos * (ux * zi)));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))), Float32(sqrt(Float32(Float32(1.0) - Float32(Float32(maxCos * ux) * Float32(maxCos * ux)))) * xi), Float32(maxCos * Float32(ux * zi))) end
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right), \sqrt{1 - \left(maxCos \cdot ux\right) \cdot \left(maxCos \cdot ux\right)} \cdot xi, maxCos \cdot \left(ux \cdot zi\right)\right)
\end{array}
Initial program 99.0%
associate-+l+99.0%
associate-*l*99.0%
fma-define99.0%
Simplified99.1%
Taylor expanded in uy around 0 59.5%
*-commutative59.5%
Simplified59.5%
Taylor expanded in ux around 0 59.5%
Taylor expanded in ux around 0 59.5%
Taylor expanded in ux around 0 57.6%
Final simplification57.6%
herbie shell --seed 2024053
(FPCore (xi yi zi ux uy maxCos)
:name "UniformSampleCone 2"
:precision binary32
:pre (and (and (and (and (and (and (<= -10000.0 xi) (<= xi 10000.0)) (and (<= -10000.0 yi) (<= yi 10000.0))) (and (<= -10000.0 zi) (<= zi 10000.0))) (and (<= 2.328306437e-10 ux) (<= ux 1.0))) (and (<= 2.328306437e-10 uy) (<= uy 1.0))) (and (<= 0.0 maxCos) (<= maxCos 1.0)))
(+ (+ (* (* (cos (* (* uy 2.0) PI)) (sqrt (- 1.0 (* (* (* (- 1.0 ux) maxCos) ux) (* (* (- 1.0 ux) maxCos) ux))))) xi) (* (* (sin (* (* uy 2.0) PI)) (sqrt (- 1.0 (* (* (* (- 1.0 ux) maxCos) ux) (* (* (- 1.0 ux) maxCos) ux))))) yi)) (* (* (* (- 1.0 ux) maxCos) ux) zi)))