
(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 3 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
(let* ((t_0 (* uy (* 2.0 PI))))
(fma
(* (- 1.0 ux) maxCos)
(* ux zi)
(*
(sqrt
(+ 1.0 (* maxCos (* (- 1.0 ux) (* (* ux ux) (* maxCos (+ ux -1.0)))))))
(+ (* (cos t_0) xi) (* (sin t_0) yi))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = uy * (2.0f * ((float) M_PI));
return fmaf(((1.0f - ux) * maxCos), (ux * zi), (sqrtf((1.0f + (maxCos * ((1.0f - ux) * ((ux * ux) * (maxCos * (ux + -1.0f))))))) * ((cosf(t_0) * xi) + (sinf(t_0) * yi))));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(uy * Float32(Float32(2.0) * Float32(pi))) return fma(Float32(Float32(Float32(1.0) - ux) * maxCos), Float32(ux * zi), Float32(sqrt(Float32(Float32(1.0) + Float32(maxCos * Float32(Float32(Float32(1.0) - ux) * Float32(Float32(ux * ux) * Float32(maxCos * Float32(ux + Float32(-1.0)))))))) * Float32(Float32(cos(t_0) * xi) + Float32(sin(t_0) * yi)))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := uy \cdot \left(2 \cdot \pi\right)\\
\mathsf{fma}\left(\left(1 - ux\right) \cdot maxCos, ux \cdot zi, \sqrt{1 + maxCos \cdot \left(\left(1 - ux\right) \cdot \left(\left(ux \cdot ux\right) \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\right)\right)} \cdot \left(\cos t\_0 \cdot xi + \sin t\_0 \cdot yi\right)\right)
\end{array}
\end{array}
Initial program 99.1%
Simplified99.1%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* ux (* (- 1.0 ux) maxCos))) (t_1 (sqrt (- 1.0 (* t_0 t_0)))))
(+
(+ (* xi (* (cos (* PI (* uy 2.0))) t_1)) (* yi (* t_1 (* 2.0 (* uy PI)))))
(* zi t_0))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = ux * ((1.0f - ux) * maxCos);
float t_1 = sqrtf((1.0f - (t_0 * t_0)));
return ((xi * (cosf((((float) M_PI) * (uy * 2.0f))) * t_1)) + (yi * (t_1 * (2.0f * (uy * ((float) M_PI)))))) + (zi * t_0);
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(ux * Float32(Float32(Float32(1.0) - ux) * maxCos)) t_1 = sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0))) return Float32(Float32(Float32(xi * Float32(cos(Float32(Float32(pi) * Float32(uy * Float32(2.0)))) * t_1)) + Float32(yi * Float32(t_1 * Float32(Float32(2.0) * Float32(uy * Float32(pi)))))) + Float32(zi * t_0)) end
function tmp = code(xi, yi, zi, ux, uy, maxCos) t_0 = ux * ((single(1.0) - ux) * maxCos); t_1 = sqrt((single(1.0) - (t_0 * t_0))); tmp = ((xi * (cos((single(pi) * (uy * single(2.0)))) * t_1)) + (yi * (t_1 * (single(2.0) * (uy * single(pi)))))) + (zi * t_0); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := ux \cdot \left(\left(1 - ux\right) \cdot maxCos\right)\\
t_1 := \sqrt{1 - t\_0 \cdot t\_0}\\
\left(xi \cdot \left(\cos \left(\pi \cdot \left(uy \cdot 2\right)\right) \cdot t\_1\right) + yi \cdot \left(t\_1 \cdot \left(2 \cdot \left(uy \cdot \pi\right)\right)\right)\right) + zi \cdot t\_0
\end{array}
\end{array}
Initial program 99.1%
associate-*r*99.1%
add-cbrt-cube99.1%
pow1/393.8%
pow393.8%
Applied egg-rr93.8%
Taylor expanded in uy around 0 86.7%
associate-*r*86.7%
metadata-eval86.7%
cube-prod86.7%
*-commutative86.7%
cube-prod86.7%
associate-*l*86.7%
Simplified86.7%
unpow1/388.0%
rem-cbrt-cube88.0%
associate-*r*88.0%
*-commutative88.0%
associate-*r*88.0%
Applied egg-rr88.0%
Final simplification88.0%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* ux (* (- 1.0 ux) maxCos))))
(+
(* zi t_0)
(+
(* xi (* (cos (* PI (* uy 2.0))) (sqrt (- 1.0 (* t_0 t_0)))))
(* 2.0 (* uy (* PI yi)))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = ux * ((1.0f - ux) * maxCos);
return (zi * t_0) + ((xi * (cosf((((float) M_PI) * (uy * 2.0f))) * sqrtf((1.0f - (t_0 * t_0))))) + (2.0f * (uy * (((float) M_PI) * yi))));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(ux * Float32(Float32(Float32(1.0) - ux) * maxCos)) return Float32(Float32(zi * t_0) + Float32(Float32(xi * Float32(cos(Float32(Float32(pi) * Float32(uy * Float32(2.0)))) * sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0))))) + Float32(Float32(2.0) * Float32(uy * Float32(Float32(pi) * yi))))) end
function tmp = code(xi, yi, zi, ux, uy, maxCos) t_0 = ux * ((single(1.0) - ux) * maxCos); tmp = (zi * t_0) + ((xi * (cos((single(pi) * (uy * single(2.0)))) * sqrt((single(1.0) - (t_0 * t_0))))) + (single(2.0) * (uy * (single(pi) * yi)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := ux \cdot \left(\left(1 - ux\right) \cdot maxCos\right)\\
zi \cdot t\_0 + \left(xi \cdot \left(\cos \left(\pi \cdot \left(uy \cdot 2\right)\right) \cdot \sqrt{1 - t\_0 \cdot t\_0}\right) + 2 \cdot \left(uy \cdot \left(\pi \cdot yi\right)\right)\right)
\end{array}
\end{array}
Initial program 99.1%
associate-*r*99.1%
add-cbrt-cube99.1%
pow1/393.8%
pow393.8%
Applied egg-rr93.8%
Taylor expanded in uy around 0 86.7%
associate-*r*86.7%
metadata-eval86.7%
cube-prod86.7%
*-commutative86.7%
cube-prod86.7%
associate-*l*86.7%
Simplified86.7%
unpow1/388.0%
rem-cbrt-cube88.0%
associate-*r*88.0%
*-commutative88.0%
associate-*r*88.0%
Applied egg-rr88.0%
Taylor expanded in ux around 0 87.9%
*-commutative87.9%
Simplified87.9%
Final simplification87.9%
herbie shell --seed 2024096
(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)))