
(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 5 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 (pow (sqrt t_0) 2.0)) 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(powf(sqrtf(t_0), 2.0f)) * 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((sqrt(t_0) ^ Float32(2.0))) * 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 \left({\left(\sqrt{t\_0}\right)}^{2}\right) \cdot xi + \sin t\_0 \cdot yi\right)\right)
\end{array}
\end{array}
Initial program 99.2%
Simplified99.2%
add-sqr-sqrt99.2%
pow299.2%
Applied egg-rr99.2%
Final simplification99.2%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* (- 1.0 ux) (* ux maxCos))))
(+
(fma
(*
(cos (* uy (* 2.0 PI)))
(sqrt (+ 1.0 (* t_0 (* (* ux maxCos) (+ ux -1.0))))))
xi
(* yi (sin (* 2.0 (* uy PI)))))
(* zi t_0))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = (1.0f - ux) * (ux * maxCos);
return fmaf((cosf((uy * (2.0f * ((float) M_PI)))) * sqrtf((1.0f + (t_0 * ((ux * maxCos) * (ux + -1.0f)))))), xi, (yi * sinf((2.0f * (uy * ((float) M_PI)))))) + (zi * t_0);
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(Float32(1.0) - ux) * Float32(ux * maxCos)) return Float32(fma(Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(Float32(1.0) + Float32(t_0 * Float32(Float32(ux * maxCos) * Float32(ux + Float32(-1.0))))))), xi, Float32(yi * sin(Float32(Float32(2.0) * Float32(uy * Float32(pi)))))) + Float32(zi * t_0)) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) \cdot \left(ux \cdot maxCos\right)\\
\mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{1 + t\_0 \cdot \left(\left(ux \cdot maxCos\right) \cdot \left(ux + -1\right)\right)}, xi, yi \cdot \sin \left(2 \cdot \left(uy \cdot \pi\right)\right)\right) + zi \cdot t\_0
\end{array}
\end{array}
Initial program 99.2%
Simplified99.2%
Taylor expanded in ux around 0 99.2%
Final simplification99.2%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* (- 1.0 ux) (* ux maxCos))))
(+
(* zi t_0)
(fma
(*
(cos (* uy (* 2.0 PI)))
(sqrt (+ 1.0 (* t_0 (* (* ux maxCos) (+ ux -1.0))))))
xi
(* yi (* 2.0 (* uy PI)))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = (1.0f - ux) * (ux * maxCos);
return (zi * t_0) + fmaf((cosf((uy * (2.0f * ((float) M_PI)))) * sqrtf((1.0f + (t_0 * ((ux * maxCos) * (ux + -1.0f)))))), xi, (yi * (2.0f * (uy * ((float) M_PI)))));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(Float32(1.0) - ux) * Float32(ux * maxCos)) return Float32(Float32(zi * t_0) + fma(Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(Float32(1.0) + Float32(t_0 * Float32(Float32(ux * maxCos) * Float32(ux + Float32(-1.0))))))), xi, Float32(yi * Float32(Float32(2.0) * Float32(uy * Float32(pi)))))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) \cdot \left(ux \cdot maxCos\right)\\
zi \cdot t\_0 + \mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{1 + t\_0 \cdot \left(\left(ux \cdot maxCos\right) \cdot \left(ux + -1\right)\right)}, xi, yi \cdot \left(2 \cdot \left(uy \cdot \pi\right)\right)\right)
\end{array}
\end{array}
Initial program 99.2%
Simplified99.2%
Taylor expanded in ux around 0 99.2%
Taylor expanded in uy around 0 89.6%
count-289.6%
*-commutative89.6%
associate-*r*89.6%
*-commutative89.6%
associate-*r*89.6%
distribute-rgt-out89.6%
count-289.6%
Simplified89.6%
Final simplification89.6%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* (- 1.0 ux) (* ux maxCos))))
(+
(* zi t_0)
(fma
(*
(cos (* uy (* 2.0 PI)))
(sqrt (+ 1.0 (* t_0 (* (* ux maxCos) (+ ux -1.0))))))
xi
(* PI (* yi (* uy 2.0)))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = (1.0f - ux) * (ux * maxCos);
return (zi * t_0) + fmaf((cosf((uy * (2.0f * ((float) M_PI)))) * sqrtf((1.0f + (t_0 * ((ux * maxCos) * (ux + -1.0f)))))), xi, (((float) M_PI) * (yi * (uy * 2.0f))));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(Float32(1.0) - ux) * Float32(ux * maxCos)) return Float32(Float32(zi * t_0) + fma(Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(Float32(1.0) + Float32(t_0 * Float32(Float32(ux * maxCos) * Float32(ux + Float32(-1.0))))))), xi, Float32(Float32(pi) * Float32(yi * Float32(uy * Float32(2.0)))))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) \cdot \left(ux \cdot maxCos\right)\\
zi \cdot t\_0 + \mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{1 + t\_0 \cdot \left(\left(ux \cdot maxCos\right) \cdot \left(ux + -1\right)\right)}, xi, \pi \cdot \left(yi \cdot \left(uy \cdot 2\right)\right)\right)
\end{array}
\end{array}
Initial program 99.2%
Simplified99.2%
Taylor expanded in ux around 0 99.2%
Taylor expanded in uy around 0 89.6%
count-289.6%
*-commutative89.6%
associate-*r*89.6%
*-commutative89.6%
associate-*r*89.6%
distribute-rgt-out89.6%
count-289.6%
Simplified89.6%
Taylor expanded in yi around 0 89.6%
*-commutative89.6%
associate-*l*89.6%
associate-*r*89.6%
*-commutative89.6%
associate-*r*89.6%
*-commutative89.6%
associate-*l*89.6%
associate-*l*89.6%
*-commutative89.6%
Simplified89.6%
Final simplification89.6%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(fma
(* (- 1.0 ux) maxCos)
(* ux zi)
(*
(sqrt
(+ 1.0 (* maxCos (* (- 1.0 ux) (* (* ux ux) (* maxCos (+ ux -1.0)))))))
(+ (* xi (cos (* uy (* 2.0 PI)))) (* (* PI yi) (* uy 2.0))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(((1.0f - ux) * maxCos), (ux * zi), (sqrtf((1.0f + (maxCos * ((1.0f - ux) * ((ux * ux) * (maxCos * (ux + -1.0f))))))) * ((xi * cosf((uy * (2.0f * ((float) M_PI))))) + ((((float) M_PI) * yi) * (uy * 2.0f)))));
}
function code(xi, yi, zi, ux, uy, maxCos) 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(xi * cos(Float32(uy * Float32(Float32(2.0) * Float32(pi))))) + Float32(Float32(Float32(pi) * yi) * Float32(uy * Float32(2.0)))))) end
\begin{array}{l}
\\
\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(xi \cdot \cos \left(uy \cdot \left(2 \cdot \pi\right)\right) + \left(\pi \cdot yi\right) \cdot \left(uy \cdot 2\right)\right)\right)
\end{array}
Initial program 99.2%
Simplified99.2%
Taylor expanded in uy around 0 89.6%
associate-*r*89.6%
*-commutative89.6%
Simplified89.6%
Final simplification89.6%
herbie shell --seed 2024084
(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)))