
(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 6 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
(cbrt
(*
(pow
(-
(* (* (- 1.0 maxCos) (+ maxCos -1.0)) (pow ux 2.0))
(* ux (+ -2.0 (* maxCos 2.0))))
1.5)
(pow (sin (* PI (* 2.0 uy))) 3.0))))
float code(float ux, float uy, float maxCos) {
return cbrtf((powf(((((1.0f - maxCos) * (maxCos + -1.0f)) * powf(ux, 2.0f)) - (ux * (-2.0f + (maxCos * 2.0f)))), 1.5f) * powf(sinf((((float) M_PI) * (2.0f * uy))), 3.0f)));
}
function code(ux, uy, maxCos) return cbrt(Float32((Float32(Float32(Float32(Float32(Float32(1.0) - maxCos) * Float32(maxCos + Float32(-1.0))) * (ux ^ Float32(2.0))) - Float32(ux * Float32(Float32(-2.0) + Float32(maxCos * Float32(2.0))))) ^ Float32(1.5)) * (sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy))) ^ Float32(3.0)))) end
\begin{array}{l}
\\
\sqrt[3]{{\left(\left(\left(1 - maxCos\right) \cdot \left(maxCos + -1\right)\right) \cdot {ux}^{2} - ux \cdot \left(-2 + maxCos \cdot 2\right)\right)}^{1.5} \cdot {\sin \left(\pi \cdot \left(2 \cdot uy\right)\right)}^{3}}
\end{array}
Initial program 59.5%
associate-*l*59.5%
sub-neg59.5%
+-commutative59.5%
distribute-rgt-neg-in59.5%
fma-def59.8%
Simplified59.7%
Taylor expanded in ux around -inf 98.4%
+-commutative98.4%
mul-1-neg98.4%
unsub-neg98.4%
*-commutative98.4%
mul-1-neg98.4%
sub-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
sub-neg98.4%
mul-1-neg98.4%
unsub-neg98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
Simplified98.4%
*-commutative98.4%
add-cbrt-cube98.3%
add-cbrt-cube98.3%
pow398.4%
cbrt-unprod98.3%
Applied egg-rr98.5%
Applied egg-rr44.7%
expm1-def98.5%
expm1-log1p98.5%
Simplified98.5%
Final simplification98.5%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sin (* 2.0 (* PI uy)))
(sqrt
(-
(* (* (- 1.0 maxCos) (+ maxCos -1.0)) (pow ux 2.0))
(* ux (- (* maxCos 2.0) 2.0))))))
float code(float ux, float uy, float maxCos) {
return sinf((2.0f * (((float) M_PI) * uy))) * sqrtf(((((1.0f - maxCos) * (maxCos + -1.0f)) * powf(ux, 2.0f)) - (ux * ((maxCos * 2.0f) - 2.0f))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(2.0) * Float32(Float32(pi) * uy))) * sqrt(Float32(Float32(Float32(Float32(Float32(1.0) - maxCos) * Float32(maxCos + Float32(-1.0))) * (ux ^ Float32(2.0))) - Float32(ux * Float32(Float32(maxCos * Float32(2.0)) - Float32(2.0)))))) end
function tmp = code(ux, uy, maxCos) tmp = sin((single(2.0) * (single(pi) * uy))) * sqrt(((((single(1.0) - maxCos) * (maxCos + single(-1.0))) * (ux ^ single(2.0))) - (ux * ((maxCos * single(2.0)) - single(2.0))))); end
\begin{array}{l}
\\
\sin \left(2 \cdot \left(\pi \cdot uy\right)\right) \cdot \sqrt{\left(\left(1 - maxCos\right) \cdot \left(maxCos + -1\right)\right) \cdot {ux}^{2} - ux \cdot \left(maxCos \cdot 2 - 2\right)}
\end{array}
Initial program 59.5%
associate-*l*59.5%
sub-neg59.5%
+-commutative59.5%
distribute-rgt-neg-in59.5%
fma-def59.8%
Simplified59.7%
Taylor expanded in ux around -inf 98.4%
+-commutative98.4%
mul-1-neg98.4%
unsub-neg98.4%
*-commutative98.4%
mul-1-neg98.4%
sub-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
sub-neg98.4%
mul-1-neg98.4%
unsub-neg98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
Simplified98.4%
Taylor expanded in uy around inf 98.4%
Final simplification98.4%
(FPCore (ux uy maxCos)
:precision binary32
(if (<= (* 2.0 uy) 0.00039999998989515007)
(*
2.0
(*
(* PI uy)
(sqrt
(-
(* (* (- 1.0 maxCos) (+ maxCos -1.0)) (pow ux 2.0))
(* ux (- (* maxCos 2.0) 2.0))))))
(* (sqrt (* ux (- 2.0 ux))) (sin (* PI (* 2.0 uy))))))
float code(float ux, float uy, float maxCos) {
float tmp;
if ((2.0f * uy) <= 0.00039999998989515007f) {
tmp = 2.0f * ((((float) M_PI) * uy) * sqrtf(((((1.0f - maxCos) * (maxCos + -1.0f)) * powf(ux, 2.0f)) - (ux * ((maxCos * 2.0f) - 2.0f)))));
} else {
tmp = sqrtf((ux * (2.0f - ux))) * sinf((((float) M_PI) * (2.0f * uy)));
}
return tmp;
}
function code(ux, uy, maxCos) tmp = Float32(0.0) if (Float32(Float32(2.0) * uy) <= Float32(0.00039999998989515007)) tmp = Float32(Float32(2.0) * Float32(Float32(Float32(pi) * uy) * sqrt(Float32(Float32(Float32(Float32(Float32(1.0) - maxCos) * Float32(maxCos + Float32(-1.0))) * (ux ^ Float32(2.0))) - Float32(ux * Float32(Float32(maxCos * Float32(2.0)) - Float32(2.0))))))); else tmp = Float32(sqrt(Float32(ux * Float32(Float32(2.0) - ux))) * sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy)))); end return tmp end
function tmp_2 = code(ux, uy, maxCos) tmp = single(0.0); if ((single(2.0) * uy) <= single(0.00039999998989515007)) tmp = single(2.0) * ((single(pi) * uy) * sqrt(((((single(1.0) - maxCos) * (maxCos + single(-1.0))) * (ux ^ single(2.0))) - (ux * ((maxCos * single(2.0)) - single(2.0)))))); else tmp = sqrt((ux * (single(2.0) - ux))) * sin((single(pi) * (single(2.0) * uy))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;2 \cdot uy \leq 0.00039999998989515007:\\
\;\;\;\;2 \cdot \left(\left(\pi \cdot uy\right) \cdot \sqrt{\left(\left(1 - maxCos\right) \cdot \left(maxCos + -1\right)\right) \cdot {ux}^{2} - ux \cdot \left(maxCos \cdot 2 - 2\right)}\right)\\
\mathbf{else}:\\
\;\;\;\;\sqrt{ux \cdot \left(2 - ux\right)} \cdot \sin \left(\pi \cdot \left(2 \cdot uy\right)\right)\\
\end{array}
\end{array}
if (*.f32 uy 2) < 3.9999999e-4Initial program 61.1%
associate-*l*61.1%
sub-neg61.1%
+-commutative61.1%
distribute-rgt-neg-in61.1%
fma-def61.3%
Simplified61.2%
Taylor expanded in ux around -inf 98.6%
+-commutative98.6%
mul-1-neg98.6%
unsub-neg98.6%
*-commutative98.6%
mul-1-neg98.6%
sub-neg98.6%
sub-neg98.6%
metadata-eval98.6%
+-commutative98.6%
sub-neg98.6%
mul-1-neg98.6%
unsub-neg98.6%
mul-1-neg98.6%
sub-neg98.6%
metadata-eval98.6%
Simplified98.6%
Taylor expanded in uy around 0 98.4%
if 3.9999999e-4 < (*.f32 uy 2) Initial program 56.9%
associate-*l*56.9%
sub-neg56.9%
+-commutative56.9%
distribute-rgt-neg-in56.9%
fma-def57.3%
Simplified57.1%
Taylor expanded in ux around -inf 98.0%
+-commutative98.0%
mul-1-neg98.0%
unsub-neg98.0%
*-commutative98.0%
mul-1-neg98.0%
sub-neg98.0%
sub-neg98.0%
metadata-eval98.0%
+-commutative98.0%
sub-neg98.0%
mul-1-neg98.0%
unsub-neg98.0%
mul-1-neg98.0%
sub-neg98.0%
metadata-eval98.0%
Simplified98.0%
Taylor expanded in maxCos around 0 92.2%
cancel-sign-sub-inv92.2%
mul-1-neg92.2%
metadata-eval92.2%
Simplified92.2%
expm1-log1p-u92.1%
*-commutative92.1%
Applied egg-rr92.1%
Taylor expanded in uy around inf 92.2%
associate-*r*92.2%
unpow292.2%
distribute-rgt-out--92.2%
Simplified92.2%
Final simplification96.1%
(FPCore (ux uy maxCos) :precision binary32 (if (<= (* 2.0 uy) 0.0044999998062849045) (* 2.0 (* (* PI uy) (sqrt (* ux (- 2.0 ux))))) (* (sin (* PI (* 2.0 uy))) (sqrt (* ux 2.0)))))
float code(float ux, float uy, float maxCos) {
float tmp;
if ((2.0f * uy) <= 0.0044999998062849045f) {
tmp = 2.0f * ((((float) M_PI) * uy) * sqrtf((ux * (2.0f - ux))));
} else {
tmp = sinf((((float) M_PI) * (2.0f * uy))) * sqrtf((ux * 2.0f));
}
return tmp;
}
function code(ux, uy, maxCos) tmp = Float32(0.0) if (Float32(Float32(2.0) * uy) <= Float32(0.0044999998062849045)) tmp = Float32(Float32(2.0) * Float32(Float32(Float32(pi) * uy) * sqrt(Float32(ux * Float32(Float32(2.0) - ux))))); else tmp = Float32(sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy))) * sqrt(Float32(ux * Float32(2.0)))); end return tmp end
function tmp_2 = code(ux, uy, maxCos) tmp = single(0.0); if ((single(2.0) * uy) <= single(0.0044999998062849045)) tmp = single(2.0) * ((single(pi) * uy) * sqrt((ux * (single(2.0) - ux)))); else tmp = sin((single(pi) * (single(2.0) * uy))) * sqrt((ux * single(2.0))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;2 \cdot uy \leq 0.0044999998062849045:\\
\;\;\;\;2 \cdot \left(\left(\pi \cdot uy\right) \cdot \sqrt{ux \cdot \left(2 - ux\right)}\right)\\
\mathbf{else}:\\
\;\;\;\;\sin \left(\pi \cdot \left(2 \cdot uy\right)\right) \cdot \sqrt{ux \cdot 2}\\
\end{array}
\end{array}
if (*.f32 uy 2) < 0.00449999981Initial program 60.3%
associate-*l*60.3%
sub-neg60.3%
+-commutative60.3%
distribute-rgt-neg-in60.3%
fma-def60.8%
Simplified60.6%
Taylor expanded in ux around -inf 98.6%
+-commutative98.6%
mul-1-neg98.6%
unsub-neg98.6%
*-commutative98.6%
mul-1-neg98.6%
sub-neg98.6%
sub-neg98.6%
metadata-eval98.6%
+-commutative98.6%
sub-neg98.6%
mul-1-neg98.6%
unsub-neg98.6%
mul-1-neg98.6%
sub-neg98.6%
metadata-eval98.6%
Simplified98.6%
Taylor expanded in maxCos around 0 92.9%
cancel-sign-sub-inv92.9%
mul-1-neg92.9%
metadata-eval92.9%
Simplified92.9%
expm1-log1p-u92.9%
*-commutative92.9%
Applied egg-rr92.9%
Taylor expanded in uy around 0 91.1%
unpow291.1%
distribute-rgt-out--91.2%
Simplified91.2%
if 0.00449999981 < (*.f32 uy 2) Initial program 57.3%
Taylor expanded in ux around 0 42.7%
Taylor expanded in maxCos around 0 72.4%
Final simplification85.9%
(FPCore (ux uy maxCos) :precision binary32 (* (sqrt (* ux (- 2.0 ux))) (sin (* PI (* 2.0 uy)))))
float code(float ux, float uy, float maxCos) {
return sqrtf((ux * (2.0f - ux))) * sinf((((float) M_PI) * (2.0f * uy)));
}
function code(ux, uy, maxCos) return Float32(sqrt(Float32(ux * Float32(Float32(2.0) - ux))) * sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy)))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((ux * (single(2.0) - ux))) * sin((single(pi) * (single(2.0) * uy))); end
\begin{array}{l}
\\
\sqrt{ux \cdot \left(2 - ux\right)} \cdot \sin \left(\pi \cdot \left(2 \cdot uy\right)\right)
\end{array}
Initial program 59.5%
associate-*l*59.5%
sub-neg59.5%
+-commutative59.5%
distribute-rgt-neg-in59.5%
fma-def59.8%
Simplified59.7%
Taylor expanded in ux around -inf 98.4%
+-commutative98.4%
mul-1-neg98.4%
unsub-neg98.4%
*-commutative98.4%
mul-1-neg98.4%
sub-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
sub-neg98.4%
mul-1-neg98.4%
unsub-neg98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
Simplified98.4%
Taylor expanded in maxCos around 0 92.6%
cancel-sign-sub-inv92.6%
mul-1-neg92.6%
metadata-eval92.6%
Simplified92.6%
expm1-log1p-u92.6%
*-commutative92.6%
Applied egg-rr92.6%
Taylor expanded in uy around inf 92.6%
associate-*r*92.6%
unpow292.6%
distribute-rgt-out--92.7%
Simplified92.7%
Final simplification92.7%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* (* PI uy) (sqrt (* ux (- 2.0 ux))))))
float code(float ux, float uy, float maxCos) {
return 2.0f * ((((float) M_PI) * uy) * sqrtf((ux * (2.0f - ux))));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(Float32(Float32(pi) * uy) * sqrt(Float32(ux * Float32(Float32(2.0) - ux))))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * ((single(pi) * uy) * sqrt((ux * (single(2.0) - ux)))); end
\begin{array}{l}
\\
2 \cdot \left(\left(\pi \cdot uy\right) \cdot \sqrt{ux \cdot \left(2 - ux\right)}\right)
\end{array}
Initial program 59.5%
associate-*l*59.5%
sub-neg59.5%
+-commutative59.5%
distribute-rgt-neg-in59.5%
fma-def59.8%
Simplified59.7%
Taylor expanded in ux around -inf 98.4%
+-commutative98.4%
mul-1-neg98.4%
unsub-neg98.4%
*-commutative98.4%
mul-1-neg98.4%
sub-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
sub-neg98.4%
mul-1-neg98.4%
unsub-neg98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
Simplified98.4%
Taylor expanded in maxCos around 0 92.6%
cancel-sign-sub-inv92.6%
mul-1-neg92.6%
metadata-eval92.6%
Simplified92.6%
expm1-log1p-u92.6%
*-commutative92.6%
Applied egg-rr92.6%
Taylor expanded in uy around 0 77.5%
unpow277.5%
distribute-rgt-out--77.5%
Simplified77.5%
Final simplification77.5%
herbie shell --seed 2023315
(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)))))))