
(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 6 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 (* (- 1.0 ux) maxCos))
(t_1 (* uy (* 2.0 PI)))
(t_2 (sqrt (+ 1.0 (* (* ux t_0) (* ux (* maxCos (+ ux -1.0))))))))
(+ (fma (* (cos t_1) t_2) xi (* (sin t_1) (* t_2 yi))) (* t_0 (* ux zi)))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = (1.0f - ux) * maxCos;
float t_1 = uy * (2.0f * ((float) M_PI));
float t_2 = sqrtf((1.0f + ((ux * t_0) * (ux * (maxCos * (ux + -1.0f))))));
return fmaf((cosf(t_1) * t_2), xi, (sinf(t_1) * (t_2 * yi))) + (t_0 * (ux * zi));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(Float32(1.0) - ux) * maxCos) t_1 = Float32(uy * Float32(Float32(2.0) * Float32(pi))) t_2 = sqrt(Float32(Float32(1.0) + Float32(Float32(ux * t_0) * Float32(ux * Float32(maxCos * Float32(ux + Float32(-1.0))))))) return Float32(fma(Float32(cos(t_1) * t_2), xi, Float32(sin(t_1) * Float32(t_2 * yi))) + Float32(t_0 * Float32(ux * zi))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) \cdot maxCos\\
t_1 := uy \cdot \left(2 \cdot \pi\right)\\
t_2 := \sqrt{1 + \left(ux \cdot t_0\right) \cdot \left(ux \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\right)}\\
\mathsf{fma}\left(\cos t_1 \cdot t_2, xi, \sin t_1 \cdot \left(t_2 \cdot yi\right)\right) + t_0 \cdot \left(ux \cdot zi\right)
\end{array}
\end{array}
Initial program 98.9%
Simplified98.9%
Final simplification98.9%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* (- 1.0 ux) maxCos)))
(+
(* t_0 (* ux zi))
(fma
(*
(cos (* uy (* 2.0 PI)))
(sqrt (+ 1.0 (* (* ux t_0) (* ux (* maxCos (+ ux -1.0)))))))
xi
(* yi (sin (* 2.0 (* uy PI))))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = (1.0f - ux) * maxCos;
return (t_0 * (ux * zi)) + fmaf((cosf((uy * (2.0f * ((float) M_PI)))) * sqrtf((1.0f + ((ux * t_0) * (ux * (maxCos * (ux + -1.0f))))))), xi, (yi * sinf((2.0f * (uy * ((float) M_PI))))));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(Float32(1.0) - ux) * maxCos) return Float32(Float32(t_0 * Float32(ux * zi)) + fma(Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(Float32(1.0) + Float32(Float32(ux * t_0) * Float32(ux * Float32(maxCos * Float32(ux + Float32(-1.0)))))))), xi, Float32(yi * sin(Float32(Float32(2.0) * Float32(uy * Float32(pi))))))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) \cdot maxCos\\
t_0 \cdot \left(ux \cdot zi\right) + \mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{1 + \left(ux \cdot t_0\right) \cdot \left(ux \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\right)}, xi, yi \cdot \sin \left(2 \cdot \left(uy \cdot \pi\right)\right)\right)
\end{array}
\end{array}
Initial program 98.9%
Simplified98.9%
Taylor expanded in ux around 0 98.9%
*-commutative98.9%
Simplified98.9%
Final simplification98.9%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(+
(* (* (- 1.0 ux) maxCos) (* ux zi))
(fma
(*
(cos (* uy (* 2.0 PI)))
(sqrt (+ 1.0 (* (* ux maxCos) (* ux (* maxCos (+ ux -1.0)))))))
xi
(* yi (sin (* 2.0 (* uy PI)))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return (((1.0f - ux) * maxCos) * (ux * zi)) + fmaf((cosf((uy * (2.0f * ((float) M_PI)))) * sqrtf((1.0f + ((ux * maxCos) * (ux * (maxCos * (ux + -1.0f))))))), xi, (yi * sinf((2.0f * (uy * ((float) M_PI))))));
}
function code(xi, yi, zi, ux, uy, maxCos) return Float32(Float32(Float32(Float32(Float32(1.0) - ux) * maxCos) * Float32(ux * zi)) + fma(Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(Float32(1.0) + Float32(Float32(ux * maxCos) * Float32(ux * Float32(maxCos * Float32(ux + Float32(-1.0)))))))), xi, Float32(yi * sin(Float32(Float32(2.0) * Float32(uy * Float32(pi))))))) end
\begin{array}{l}
\\
\left(\left(1 - ux\right) \cdot maxCos\right) \cdot \left(ux \cdot zi\right) + \mathsf{fma}\left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{1 + \left(ux \cdot maxCos\right) \cdot \left(ux \cdot \left(maxCos \cdot \left(ux + -1\right)\right)\right)}, xi, yi \cdot \sin \left(2 \cdot \left(uy \cdot \pi\right)\right)\right)
\end{array}
Initial program 98.9%
Simplified98.9%
Taylor expanded in ux around 0 98.9%
*-commutative98.9%
Simplified98.9%
Taylor expanded in ux around 0 98.9%
*-commutative98.9%
Simplified98.9%
Final simplification98.9%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* uy (* 2.0 PI))))
(fma
ux
(* (- 1.0 ux) (* maxCos zi))
(*
(sqrt (- 1.0 (* ux (* ux (* maxCos maxCos)))))
(+ (* (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(ux, ((1.0f - ux) * (maxCos * zi)), (sqrtf((1.0f - (ux * (ux * (maxCos * maxCos))))) * ((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(ux, Float32(Float32(Float32(1.0) - ux) * Float32(maxCos * zi)), Float32(sqrt(Float32(Float32(1.0) - Float32(ux * Float32(ux * Float32(maxCos * maxCos))))) * 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(ux, \left(1 - ux\right) \cdot \left(maxCos \cdot zi\right), \sqrt{1 - ux \cdot \left(ux \cdot \left(maxCos \cdot maxCos\right)\right)} \cdot \left(\cos t_0 \cdot xi + \sin t_0 \cdot yi\right)\right)
\end{array}
\end{array}
Initial program 98.9%
+-commutative98.9%
*-commutative98.9%
associate-*l*98.9%
fma-def98.9%
Simplified98.9%
Taylor expanded in ux around 0 98.9%
Final simplification98.9%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma ux (* (- 1.0 ux) (* maxCos zi)) (* (sqrt (+ 1.0 (* ux (* ux (* maxCos (* maxCos (- -1.0 (* ux -2.0)))))))) (+ (* (cos (* uy (* 2.0 PI))) xi) (* 2.0 (* uy (* PI yi)))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(ux, ((1.0f - ux) * (maxCos * zi)), (sqrtf((1.0f + (ux * (ux * (maxCos * (maxCos * (-1.0f - (ux * -2.0f)))))))) * ((cosf((uy * (2.0f * ((float) M_PI)))) * xi) + (2.0f * (uy * (((float) M_PI) * yi))))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(ux, Float32(Float32(Float32(1.0) - ux) * Float32(maxCos * zi)), Float32(sqrt(Float32(Float32(1.0) + Float32(ux * Float32(ux * Float32(maxCos * Float32(maxCos * Float32(Float32(-1.0) - Float32(ux * Float32(-2.0))))))))) * Float32(Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * xi) + Float32(Float32(2.0) * Float32(uy * Float32(Float32(pi) * yi)))))) end
\begin{array}{l}
\\
\mathsf{fma}\left(ux, \left(1 - ux\right) \cdot \left(maxCos \cdot zi\right), \sqrt{1 + ux \cdot \left(ux \cdot \left(maxCos \cdot \left(maxCos \cdot \left(-1 - ux \cdot -2\right)\right)\right)\right)} \cdot \left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot xi + 2 \cdot \left(uy \cdot \left(\pi \cdot yi\right)\right)\right)\right)
\end{array}
Initial program 98.9%
+-commutative98.9%
*-commutative98.9%
associate-*l*98.9%
fma-def98.9%
Simplified98.9%
Taylor expanded in uy around 0 89.5%
Taylor expanded in ux around 0 89.5%
*-commutative89.5%
Simplified89.5%
Final simplification89.5%
(FPCore (xi yi zi ux uy maxCos) :precision binary32 (fma ux (* (- 1.0 ux) (* maxCos zi)) (* (sqrt (- 1.0 (* ux (* ux (* maxCos maxCos))))) (+ (* (cos (* uy (* 2.0 PI))) xi) (* 2.0 (* uy (* PI yi)))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
return fmaf(ux, ((1.0f - ux) * (maxCos * zi)), (sqrtf((1.0f - (ux * (ux * (maxCos * maxCos))))) * ((cosf((uy * (2.0f * ((float) M_PI)))) * xi) + (2.0f * (uy * (((float) M_PI) * yi))))));
}
function code(xi, yi, zi, ux, uy, maxCos) return fma(ux, Float32(Float32(Float32(1.0) - ux) * Float32(maxCos * zi)), Float32(sqrt(Float32(Float32(1.0) - Float32(ux * Float32(ux * Float32(maxCos * maxCos))))) * Float32(Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * xi) + Float32(Float32(2.0) * Float32(uy * Float32(Float32(pi) * yi)))))) end
\begin{array}{l}
\\
\mathsf{fma}\left(ux, \left(1 - ux\right) \cdot \left(maxCos \cdot zi\right), \sqrt{1 - ux \cdot \left(ux \cdot \left(maxCos \cdot maxCos\right)\right)} \cdot \left(\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot xi + 2 \cdot \left(uy \cdot \left(\pi \cdot yi\right)\right)\right)\right)
\end{array}
Initial program 98.9%
+-commutative98.9%
*-commutative98.9%
associate-*l*98.9%
fma-def98.9%
Simplified98.9%
Taylor expanded in uy around 0 89.5%
Taylor expanded in ux around 0 89.4%
Final simplification89.4%
herbie shell --seed 2023178
(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)))