
(FPCore (ux uy maxCos) :precision binary32 (let* ((t_0 (+ (- 1.0 ux) (* ux maxCos)))) (* (sin (* (* uy 2.0) PI)) (sqrt (- 1.0 (* t_0 t_0))))))
float code(float ux, float uy, float maxCos) {
float t_0 = (1.0f - ux) + (ux * maxCos);
return sinf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((1.0f - (t_0 * t_0)));
}
function code(ux, uy, maxCos) t_0 = Float32(Float32(Float32(1.0) - ux) + Float32(ux * maxCos)) return Float32(sin(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0)))) end
function tmp = code(ux, uy, maxCos) t_0 = (single(1.0) - ux) + (ux * maxCos); tmp = sin(((uy * single(2.0)) * single(pi))) * sqrt((single(1.0) - (t_0 * t_0))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) + ux \cdot maxCos\\
\sin \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{1 - t\_0 \cdot t\_0}
\end{array}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 10 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (ux uy maxCos) :precision binary32 (let* ((t_0 (+ (- 1.0 ux) (* ux maxCos)))) (* (sin (* (* uy 2.0) PI)) (sqrt (- 1.0 (* t_0 t_0))))))
float code(float ux, float uy, float maxCos) {
float t_0 = (1.0f - ux) + (ux * maxCos);
return sinf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((1.0f - (t_0 * t_0)));
}
function code(ux, uy, maxCos) t_0 = Float32(Float32(Float32(1.0) - ux) + Float32(ux * maxCos)) return Float32(sin(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0)))) end
function tmp = code(ux, uy, maxCos) t_0 = (single(1.0) - ux) + (ux * maxCos); tmp = sin(((uy * single(2.0)) * single(pi))) * sqrt((single(1.0) - (t_0 * t_0))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) + ux \cdot maxCos\\
\sin \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{1 - t\_0 \cdot t\_0}
\end{array}
\end{array}
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* (log1p (expm1 (* uy 2.0))) PI)) (sqrt (* ux (- 2.0 (+ (* 2.0 maxCos) (* ux (pow (+ -1.0 maxCos) 2.0))))))))
float code(float ux, float uy, float maxCos) {
return sinf((log1pf(expm1f((uy * 2.0f))) * ((float) M_PI))) * sqrtf((ux * (2.0f - ((2.0f * maxCos) + (ux * powf((-1.0f + maxCos), 2.0f))))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(log1p(expm1(Float32(uy * Float32(2.0)))) * Float32(pi))) * sqrt(Float32(ux * Float32(Float32(2.0) - Float32(Float32(Float32(2.0) * maxCos) + Float32(ux * (Float32(Float32(-1.0) + maxCos) ^ Float32(2.0)))))))) end
\begin{array}{l}
\\
\sin \left(\mathsf{log1p}\left(\mathsf{expm1}\left(uy \cdot 2\right)\right) \cdot \pi\right) \cdot \sqrt{ux \cdot \left(2 - \left(2 \cdot maxCos + ux \cdot {\left(-1 + maxCos\right)}^{2}\right)\right)}
\end{array}
Initial program 56.9%
Taylor expanded in ux around 0 98.4%
associate--l+98.4%
associate-*r*98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
log1p-expm1-u98.5%
Applied egg-rr98.5%
Final simplification98.5%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* (* uy 2.0) PI)) (sqrt (* ux (- 2.0 (+ ux (* maxCos (+ 2.0 (* ux (+ maxCos -2.0))))))))))
float code(float ux, float uy, float maxCos) {
return sinf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((ux * (2.0f - (ux + (maxCos * (2.0f + (ux * (maxCos + -2.0f))))))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(ux * Float32(Float32(2.0) - Float32(ux + Float32(maxCos * Float32(Float32(2.0) + Float32(ux * Float32(maxCos + Float32(-2.0)))))))))) end
function tmp = code(ux, uy, maxCos) tmp = sin(((uy * single(2.0)) * single(pi))) * sqrt((ux * (single(2.0) - (ux + (maxCos * (single(2.0) + (ux * (maxCos + single(-2.0))))))))); end
\begin{array}{l}
\\
\sin \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{ux \cdot \left(2 - \left(ux + maxCos \cdot \left(2 + ux \cdot \left(maxCos + -2\right)\right)\right)\right)}
\end{array}
Initial program 56.9%
Taylor expanded in ux around 0 98.4%
associate--l+98.4%
associate-*r*98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in maxCos around 0 98.4%
Taylor expanded in ux around -inf 98.4%
associate-*r*98.4%
neg-mul-198.4%
sub-neg98.4%
metadata-eval98.4%
Simplified98.4%
Final simplification98.4%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* (* uy 2.0) PI)) (sqrt (* ux (+ 2.0 (- (* maxCos (- (* 2.0 ux) 2.0)) ux))))))
float code(float ux, float uy, float maxCos) {
return sinf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((ux * (2.0f + ((maxCos * ((2.0f * ux) - 2.0f)) - ux))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(maxCos * Float32(Float32(Float32(2.0) * ux) - Float32(2.0))) - ux))))) end
function tmp = code(ux, uy, maxCos) tmp = sin(((uy * single(2.0)) * single(pi))) * sqrt((ux * (single(2.0) + ((maxCos * ((single(2.0) * ux) - single(2.0))) - ux)))); end
\begin{array}{l}
\\
\sin \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{ux \cdot \left(2 + \left(maxCos \cdot \left(2 \cdot ux - 2\right) - ux\right)\right)}
\end{array}
Initial program 56.9%
Taylor expanded in ux around 0 98.4%
associate--l+98.4%
associate-*r*98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in maxCos around 0 98.0%
Final simplification98.0%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* (* uy 2.0) PI)) (sqrt (* ux (- 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
return sinf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((ux * (2.0f - ux)));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(ux * Float32(Float32(2.0) - ux)))) end
function tmp = code(ux, uy, maxCos) tmp = sin(((uy * single(2.0)) * single(pi))) * sqrt((ux * (single(2.0) - ux))); end
\begin{array}{l}
\\
\sin \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{ux \cdot \left(2 - ux\right)}
\end{array}
Initial program 56.9%
Taylor expanded in ux around 0 98.4%
associate--l+98.4%
associate-*r*98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
log1p-expm1-u98.5%
Applied egg-rr98.5%
Taylor expanded in maxCos around 0 94.3%
*-commutative94.3%
associate-*r*94.3%
*-commutative94.3%
*-commutative94.3%
*-commutative94.3%
mul-1-neg94.3%
unsub-neg94.3%
Simplified94.3%
Final simplification94.3%
(FPCore (ux uy maxCos) :precision binary32 (* (* 2.0 (* uy PI)) (sqrt (* ux (+ 2.0 (- (* maxCos (- (- (* 2.0 ux) (* ux maxCos)) 2.0)) ux))))))
float code(float ux, float uy, float maxCos) {
return (2.0f * (uy * ((float) M_PI))) * sqrtf((ux * (2.0f + ((maxCos * (((2.0f * ux) - (ux * maxCos)) - 2.0f)) - ux))));
}
function code(ux, uy, maxCos) return Float32(Float32(Float32(2.0) * Float32(uy * Float32(pi))) * sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(maxCos * Float32(Float32(Float32(Float32(2.0) * ux) - Float32(ux * maxCos)) - Float32(2.0))) - ux))))) end
function tmp = code(ux, uy, maxCos) tmp = (single(2.0) * (uy * single(pi))) * sqrt((ux * (single(2.0) + ((maxCos * (((single(2.0) * ux) - (ux * maxCos)) - single(2.0))) - ux)))); end
\begin{array}{l}
\\
\left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(2 + \left(maxCos \cdot \left(\left(2 \cdot ux - ux \cdot maxCos\right) - 2\right) - ux\right)\right)}
\end{array}
Initial program 56.9%
Taylor expanded in ux around 0 98.4%
associate--l+98.4%
associate-*r*98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in uy around 0 80.8%
Taylor expanded in maxCos around 0 80.8%
Final simplification80.8%
(FPCore (ux uy maxCos) :precision binary32 (* (sqrt (* ux (+ 2.0 (- (* maxCos (- (* 2.0 ux) 2.0)) ux)))) (* 2.0 (* uy PI))))
float code(float ux, float uy, float maxCos) {
return sqrtf((ux * (2.0f + ((maxCos * ((2.0f * ux) - 2.0f)) - ux)))) * (2.0f * (uy * ((float) M_PI)));
}
function code(ux, uy, maxCos) return Float32(sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(maxCos * Float32(Float32(Float32(2.0) * ux) - Float32(2.0))) - ux)))) * Float32(Float32(2.0) * Float32(uy * Float32(pi)))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((ux * (single(2.0) + ((maxCos * ((single(2.0) * ux) - single(2.0))) - ux)))) * (single(2.0) * (uy * single(pi))); end
\begin{array}{l}
\\
\sqrt{ux \cdot \left(2 + \left(maxCos \cdot \left(2 \cdot ux - 2\right) - ux\right)\right)} \cdot \left(2 \cdot \left(uy \cdot \pi\right)\right)
\end{array}
Initial program 56.9%
Taylor expanded in ux around 0 98.4%
associate--l+98.4%
associate-*r*98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in uy around 0 80.8%
Taylor expanded in maxCos around 0 80.4%
Final simplification80.4%
(FPCore (ux uy maxCos) :precision binary32 (* (* 2.0 (* uy PI)) (sqrt (* ux (* ux (+ -1.0 (/ (+ 2.0 (* maxCos -2.0)) ux)))))))
float code(float ux, float uy, float maxCos) {
return (2.0f * (uy * ((float) M_PI))) * sqrtf((ux * (ux * (-1.0f + ((2.0f + (maxCos * -2.0f)) / ux)))));
}
function code(ux, uy, maxCos) return Float32(Float32(Float32(2.0) * Float32(uy * Float32(pi))) * sqrt(Float32(ux * Float32(ux * Float32(Float32(-1.0) + Float32(Float32(Float32(2.0) + Float32(maxCos * Float32(-2.0))) / ux)))))) end
function tmp = code(ux, uy, maxCos) tmp = (single(2.0) * (uy * single(pi))) * sqrt((ux * (ux * (single(-1.0) + ((single(2.0) + (maxCos * single(-2.0))) / ux))))); end
\begin{array}{l}
\\
\left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(ux \cdot \left(-1 + \frac{2 + maxCos \cdot -2}{ux}\right)\right)}
\end{array}
Initial program 56.9%
Taylor expanded in ux around 0 98.4%
associate--l+98.4%
associate-*r*98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in uy around 0 80.8%
Taylor expanded in ux around inf 80.8%
associate--l+80.8%
mul-1-neg80.8%
sub-neg80.8%
metadata-eval80.8%
+-commutative80.8%
associate-*r/80.8%
metadata-eval80.8%
associate-*r/80.8%
div-sub80.8%
cancel-sign-sub-inv80.8%
metadata-eval80.8%
*-commutative80.8%
Simplified80.8%
Taylor expanded in maxCos around 0 80.1%
(FPCore (ux uy maxCos) :precision binary32 (* (* 2.0 (* uy PI)) (sqrt (* ux (* ux (+ -1.0 (/ 2.0 ux)))))))
float code(float ux, float uy, float maxCos) {
return (2.0f * (uy * ((float) M_PI))) * sqrtf((ux * (ux * (-1.0f + (2.0f / ux)))));
}
function code(ux, uy, maxCos) return Float32(Float32(Float32(2.0) * Float32(uy * Float32(pi))) * sqrt(Float32(ux * Float32(ux * Float32(Float32(-1.0) + Float32(Float32(2.0) / ux)))))) end
function tmp = code(ux, uy, maxCos) tmp = (single(2.0) * (uy * single(pi))) * sqrt((ux * (ux * (single(-1.0) + (single(2.0) / ux))))); end
\begin{array}{l}
\\
\left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(ux \cdot \left(-1 + \frac{2}{ux}\right)\right)}
\end{array}
Initial program 56.9%
Taylor expanded in ux around 0 98.4%
associate--l+98.4%
associate-*r*98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in uy around 0 80.8%
Taylor expanded in ux around inf 80.8%
associate--l+80.8%
mul-1-neg80.8%
sub-neg80.8%
metadata-eval80.8%
+-commutative80.8%
associate-*r/80.8%
metadata-eval80.8%
associate-*r/80.8%
div-sub80.8%
cancel-sign-sub-inv80.8%
metadata-eval80.8%
*-commutative80.8%
Simplified80.8%
Taylor expanded in maxCos around 0 77.7%
sub-neg77.7%
associate-*r/77.7%
metadata-eval77.7%
metadata-eval77.7%
Simplified77.7%
Final simplification77.7%
(FPCore (ux uy maxCos) :precision binary32 (* (sqrt (* ux (- 2.0 ux))) (* 2.0 (* uy PI))))
float code(float ux, float uy, float maxCos) {
return sqrtf((ux * (2.0f - ux))) * (2.0f * (uy * ((float) M_PI)));
}
function code(ux, uy, maxCos) return Float32(sqrt(Float32(ux * Float32(Float32(2.0) - ux))) * Float32(Float32(2.0) * Float32(uy * Float32(pi)))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((ux * (single(2.0) - ux))) * (single(2.0) * (uy * single(pi))); end
\begin{array}{l}
\\
\sqrt{ux \cdot \left(2 - ux\right)} \cdot \left(2 \cdot \left(uy \cdot \pi\right)\right)
\end{array}
Initial program 56.9%
Taylor expanded in ux around 0 98.4%
associate--l+98.4%
associate-*r*98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in uy around 0 80.8%
Taylor expanded in maxCos around 0 77.7%
mul-1-neg77.7%
unsub-neg77.7%
Simplified77.7%
Final simplification77.7%
(FPCore (ux uy maxCos) :precision binary32 0.0)
float code(float ux, float uy, float maxCos) {
return 0.0f;
}
real(4) function code(ux, uy, maxcos)
real(4), intent (in) :: ux
real(4), intent (in) :: uy
real(4), intent (in) :: maxcos
code = 0.0e0
end function
function code(ux, uy, maxCos) return Float32(0.0) end
function tmp = code(ux, uy, maxCos) tmp = single(0.0); end
\begin{array}{l}
\\
0
\end{array}
Initial program 56.9%
associate-*l*56.9%
sub-neg56.9%
+-commutative56.9%
distribute-rgt-neg-in56.9%
fma-define57.1%
Simplified57.1%
Taylor expanded in uy around 0 49.1%
Simplified49.2%
Taylor expanded in ux around 0 7.1%
Taylor expanded in uy around 0 7.1%
herbie shell --seed 2024139
(FPCore (ux uy maxCos)
:name "UniformSampleCone, y"
:precision binary32
:pre (and (and (and (<= 2.328306437e-10 ux) (<= ux 1.0)) (and (<= 2.328306437e-10 uy) (<= uy 1.0))) (and (<= 0.0 maxCos) (<= maxCos 1.0)))
(* (sin (* (* uy 2.0) PI)) (sqrt (- 1.0 (* (+ (- 1.0 ux) (* ux maxCos)) (+ (- 1.0 ux) (* ux maxCos)))))))