
(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 (* (* ux maxCos) (+ ux -1.0)))
(t_1 (* uy (* 2.0 PI)))
(t_2 (sqrt (- 1.0 (* t_0 t_0)))))
(fma
(cos t_1)
(* xi t_2)
(fma (sin t_1) (* yi t_2) (* (- 1.0 ux) (* (* ux maxCos) zi))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = (ux * maxCos) * (ux + -1.0f);
float t_1 = uy * (2.0f * ((float) M_PI));
float t_2 = sqrtf((1.0f - (t_0 * t_0)));
return fmaf(cosf(t_1), (xi * t_2), fmaf(sinf(t_1), (yi * t_2), ((1.0f - ux) * ((ux * maxCos) * zi))));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(ux * maxCos) * Float32(ux + Float32(-1.0))) t_1 = Float32(uy * Float32(Float32(2.0) * Float32(pi))) t_2 = sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0))) return fma(cos(t_1), Float32(xi * t_2), fma(sin(t_1), Float32(yi * t_2), Float32(Float32(Float32(1.0) - ux) * Float32(Float32(ux * maxCos) * zi)))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(ux \cdot maxCos\right) \cdot \left(ux + -1\right)\\
t_1 := uy \cdot \left(2 \cdot \pi\right)\\
t_2 := \sqrt{1 - t\_0 \cdot t\_0}\\
\mathsf{fma}\left(\cos t\_1, xi \cdot t\_2, \mathsf{fma}\left(\sin t\_1, yi \cdot t\_2, \left(1 - ux\right) \cdot \left(\left(ux \cdot maxCos\right) \cdot zi\right)\right)\right)
\end{array}
\end{array}
Initial program 98.8%
associate-+l+98.8%
associate-*l*98.8%
fma-def98.9%
Simplified98.9%
Final simplification98.9%
(FPCore (xi yi zi ux uy maxCos)
:precision binary32
(let* ((t_0 (* (* ux maxCos) (+ ux -1.0)))
(t_1 (* uy (* 2.0 PI)))
(t_2 (sqrt (- 1.0 (* t_0 t_0)))))
(+
(fma (* (cos t_1) t_2) xi (* (sin t_1) (* yi t_2)))
(* zi (* (- 1.0 ux) (* ux maxCos))))))
float code(float xi, float yi, float zi, float ux, float uy, float maxCos) {
float t_0 = (ux * maxCos) * (ux + -1.0f);
float t_1 = uy * (2.0f * ((float) M_PI));
float t_2 = sqrtf((1.0f - (t_0 * t_0)));
return fmaf((cosf(t_1) * t_2), xi, (sinf(t_1) * (yi * t_2))) + (zi * ((1.0f - ux) * (ux * maxCos)));
}
function code(xi, yi, zi, ux, uy, maxCos) t_0 = Float32(Float32(ux * maxCos) * Float32(ux + Float32(-1.0))) t_1 = Float32(uy * Float32(Float32(2.0) * Float32(pi))) t_2 = sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0))) return Float32(fma(Float32(cos(t_1) * t_2), xi, Float32(sin(t_1) * Float32(yi * t_2))) + Float32(zi * Float32(Float32(Float32(1.0) - ux) * Float32(ux * maxCos)))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(ux \cdot maxCos\right) \cdot \left(ux + -1\right)\\
t_1 := uy \cdot \left(2 \cdot \pi\right)\\
t_2 := \sqrt{1 - t\_0 \cdot t\_0}\\
\mathsf{fma}\left(\cos t\_1 \cdot t\_2, xi, \sin t\_1 \cdot \left(yi \cdot t\_2\right)\right) + zi \cdot \left(\left(1 - ux\right) \cdot \left(ux \cdot maxCos\right)\right)
\end{array}
\end{array}
Initial program 98.8%
Simplified98.9%
Final simplification98.9%
(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 98.8%
Simplified98.8%
Final simplification98.8%
herbie shell --seed 2024034
(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)))