
(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 8 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
(fma
ux
(* 2.0 (- 1.0 maxCos))
(* (pow ux 2.0) (* (- 1.0 maxCos) (+ maxCos -1.0))))
1.5)
(pow (sin (* 2.0 (* uy PI))) 3.0))))
float code(float ux, float uy, float maxCos) {
return cbrtf((powf(fmaf(ux, (2.0f * (1.0f - maxCos)), (powf(ux, 2.0f) * ((1.0f - maxCos) * (maxCos + -1.0f)))), 1.5f) * powf(sinf((2.0f * (uy * ((float) M_PI)))), 3.0f)));
}
function code(ux, uy, maxCos) return cbrt(Float32((fma(ux, Float32(Float32(2.0) * Float32(Float32(1.0) - maxCos)), Float32((ux ^ Float32(2.0)) * Float32(Float32(Float32(1.0) - maxCos) * Float32(maxCos + Float32(-1.0))))) ^ Float32(1.5)) * (sin(Float32(Float32(2.0) * Float32(uy * Float32(pi)))) ^ Float32(3.0)))) end
\begin{array}{l}
\\
\sqrt[3]{{\left(\mathsf{fma}\left(ux, 2 \cdot \left(1 - maxCos\right), {ux}^{2} \cdot \left(\left(1 - maxCos\right) \cdot \left(maxCos + -1\right)\right)\right)\right)}^{1.5} \cdot {\sin \left(2 \cdot \left(uy \cdot \pi\right)\right)}^{3}}
\end{array}
Initial program 55.7%
associate-*l*55.7%
sub-neg55.7%
+-commutative55.7%
distribute-rgt-neg-in55.7%
fma-def55.9%
Simplified55.9%
Taylor expanded in ux around 0 98.3%
fma-def98.4%
+-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
distribute-lft-in98.4%
metadata-eval98.4%
associate--l+98.4%
mul-1-neg98.4%
sub-neg98.4%
*-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
*-commutative98.4%
add-cbrt-cube98.4%
*-commutative98.4%
associate-*r*98.4%
add-cbrt-cube98.4%
cbrt-unprod98.3%
Applied egg-rr98.4%
Final simplification98.4%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sqrt
(fma
ux
(+ 2.0 (* maxCos -2.0))
(* (pow ux 2.0) (* (- 1.0 maxCos) (+ maxCos -1.0)))))
(sin (* PI (* 2.0 uy)))))
float code(float ux, float uy, float maxCos) {
return sqrtf(fmaf(ux, (2.0f + (maxCos * -2.0f)), (powf(ux, 2.0f) * ((1.0f - maxCos) * (maxCos + -1.0f))))) * sinf((((float) M_PI) * (2.0f * uy)));
}
function code(ux, uy, maxCos) return Float32(sqrt(fma(ux, Float32(Float32(2.0) + Float32(maxCos * Float32(-2.0))), Float32((ux ^ Float32(2.0)) * Float32(Float32(Float32(1.0) - maxCos) * Float32(maxCos + Float32(-1.0)))))) * sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy)))) end
\begin{array}{l}
\\
\sqrt{\mathsf{fma}\left(ux, 2 + maxCos \cdot -2, {ux}^{2} \cdot \left(\left(1 - maxCos\right) \cdot \left(maxCos + -1\right)\right)\right)} \cdot \sin \left(\pi \cdot \left(2 \cdot uy\right)\right)
\end{array}
Initial program 55.7%
associate-*l*55.7%
sub-neg55.7%
+-commutative55.7%
distribute-rgt-neg-in55.7%
fma-def55.9%
Simplified55.9%
Taylor expanded in ux around 0 98.3%
fma-def98.4%
+-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
distribute-lft-in98.4%
metadata-eval98.4%
associate--l+98.4%
mul-1-neg98.4%
sub-neg98.4%
*-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in uy around inf 98.4%
*-commutative98.4%
fma-def98.4%
cancel-sign-sub-inv98.4%
metadata-eval98.4%
*-commutative98.4%
*-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
associate-*r*98.4%
Simplified98.4%
Final simplification98.4%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sin (* 2.0 (* uy PI)))
(sqrt
(+
(* (pow ux 2.0) (* (- 1.0 maxCos) (+ maxCos -1.0)))
(* ux (- 2.0 (* 2.0 maxCos)))))))
float code(float ux, float uy, float maxCos) {
return sinf((2.0f * (uy * ((float) M_PI)))) * sqrtf(((powf(ux, 2.0f) * ((1.0f - maxCos) * (maxCos + -1.0f))) + (ux * (2.0f - (2.0f * maxCos)))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(2.0) * Float32(uy * Float32(pi)))) * sqrt(Float32(Float32((ux ^ Float32(2.0)) * Float32(Float32(Float32(1.0) - maxCos) * Float32(maxCos + Float32(-1.0)))) + Float32(ux * Float32(Float32(2.0) - Float32(Float32(2.0) * maxCos)))))) end
function tmp = code(ux, uy, maxCos) tmp = sin((single(2.0) * (uy * single(pi)))) * sqrt((((ux ^ single(2.0)) * ((single(1.0) - maxCos) * (maxCos + single(-1.0)))) + (ux * (single(2.0) - (single(2.0) * maxCos))))); end
\begin{array}{l}
\\
\sin \left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{{ux}^{2} \cdot \left(\left(1 - maxCos\right) \cdot \left(maxCos + -1\right)\right) + ux \cdot \left(2 - 2 \cdot maxCos\right)}
\end{array}
Initial program 55.7%
associate-*l*55.7%
sub-neg55.7%
+-commutative55.7%
distribute-rgt-neg-in55.7%
fma-def55.9%
Simplified55.9%
Taylor expanded in ux around 0 98.3%
fma-def98.4%
+-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
distribute-lft-in98.4%
metadata-eval98.4%
associate--l+98.4%
mul-1-neg98.4%
sub-neg98.4%
*-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in uy around inf 98.4%
Final simplification98.4%
(FPCore (ux uy maxCos)
:precision binary32
(let* ((t_0 (sin (* PI (* 2.0 uy)))))
(if (<= maxCos 4.999999987376214e-7)
(* t_0 (sqrt (- (* ux 2.0) (pow ux 2.0))))
(* t_0 (sqrt (* ux (- 2.0 (* 2.0 maxCos))))))))
float code(float ux, float uy, float maxCos) {
float t_0 = sinf((((float) M_PI) * (2.0f * uy)));
float tmp;
if (maxCos <= 4.999999987376214e-7f) {
tmp = t_0 * sqrtf(((ux * 2.0f) - powf(ux, 2.0f)));
} else {
tmp = t_0 * sqrtf((ux * (2.0f - (2.0f * maxCos))));
}
return tmp;
}
function code(ux, uy, maxCos) t_0 = sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy))) tmp = Float32(0.0) if (maxCos <= Float32(4.999999987376214e-7)) tmp = Float32(t_0 * sqrt(Float32(Float32(ux * Float32(2.0)) - (ux ^ Float32(2.0))))); else tmp = Float32(t_0 * sqrt(Float32(ux * Float32(Float32(2.0) - Float32(Float32(2.0) * maxCos))))); end return tmp end
function tmp_2 = code(ux, uy, maxCos) t_0 = sin((single(pi) * (single(2.0) * uy))); tmp = single(0.0); if (maxCos <= single(4.999999987376214e-7)) tmp = t_0 * sqrt(((ux * single(2.0)) - (ux ^ single(2.0)))); else tmp = t_0 * sqrt((ux * (single(2.0) - (single(2.0) * maxCos)))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sin \left(\pi \cdot \left(2 \cdot uy\right)\right)\\
\mathbf{if}\;maxCos \leq 4.999999987376214 \cdot 10^{-7}:\\
\;\;\;\;t_0 \cdot \sqrt{ux \cdot 2 - {ux}^{2}}\\
\mathbf{else}:\\
\;\;\;\;t_0 \cdot \sqrt{ux \cdot \left(2 - 2 \cdot maxCos\right)}\\
\end{array}
\end{array}
if maxCos < 4.99999999e-7Initial program 58.2%
associate-*l*58.2%
sub-neg58.2%
+-commutative58.2%
distribute-rgt-neg-in58.2%
fma-def58.4%
Simplified58.4%
Taylor expanded in ux around 0 98.4%
fma-def98.4%
+-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
distribute-lft-in98.4%
metadata-eval98.4%
associate--l+98.4%
mul-1-neg98.4%
sub-neg98.4%
*-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in maxCos around 0 98.3%
associate-*r*98.3%
+-commutative98.3%
neg-mul-198.3%
unsub-neg98.3%
Simplified98.3%
if 4.99999999e-7 < maxCos Initial program 35.3%
Taylor expanded in ux around 0 88.6%
*-commutative88.6%
Simplified88.6%
Final simplification97.2%
(FPCore (ux uy maxCos)
:precision binary32
(let* ((t_0 (sin (* PI (* 2.0 uy)))))
(if (<= maxCos 4.999999987376214e-7)
(* t_0 (sqrt (* ux (- 2.0 ux))))
(* t_0 (sqrt (* ux (- 2.0 (* 2.0 maxCos))))))))
float code(float ux, float uy, float maxCos) {
float t_0 = sinf((((float) M_PI) * (2.0f * uy)));
float tmp;
if (maxCos <= 4.999999987376214e-7f) {
tmp = t_0 * sqrtf((ux * (2.0f - ux)));
} else {
tmp = t_0 * sqrtf((ux * (2.0f - (2.0f * maxCos))));
}
return tmp;
}
function code(ux, uy, maxCos) t_0 = sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy))) tmp = Float32(0.0) if (maxCos <= Float32(4.999999987376214e-7)) tmp = Float32(t_0 * sqrt(Float32(ux * Float32(Float32(2.0) - ux)))); else tmp = Float32(t_0 * sqrt(Float32(ux * Float32(Float32(2.0) - Float32(Float32(2.0) * maxCos))))); end return tmp end
function tmp_2 = code(ux, uy, maxCos) t_0 = sin((single(pi) * (single(2.0) * uy))); tmp = single(0.0); if (maxCos <= single(4.999999987376214e-7)) tmp = t_0 * sqrt((ux * (single(2.0) - ux))); else tmp = t_0 * sqrt((ux * (single(2.0) - (single(2.0) * maxCos)))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sin \left(\pi \cdot \left(2 \cdot uy\right)\right)\\
\mathbf{if}\;maxCos \leq 4.999999987376214 \cdot 10^{-7}:\\
\;\;\;\;t_0 \cdot \sqrt{ux \cdot \left(2 - ux\right)}\\
\mathbf{else}:\\
\;\;\;\;t_0 \cdot \sqrt{ux \cdot \left(2 - 2 \cdot maxCos\right)}\\
\end{array}
\end{array}
if maxCos < 4.99999999e-7Initial program 58.2%
associate-*l*58.2%
sub-neg58.2%
+-commutative58.2%
distribute-rgt-neg-in58.2%
fma-def58.4%
Simplified58.4%
Taylor expanded in ux around 0 98.4%
fma-def98.4%
+-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
distribute-lft-in98.4%
metadata-eval98.4%
associate--l+98.4%
mul-1-neg98.4%
sub-neg98.4%
*-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in uy around inf 98.4%
*-commutative98.4%
fma-def98.4%
cancel-sign-sub-inv98.4%
metadata-eval98.4%
*-commutative98.4%
*-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
associate-*r*98.4%
Simplified98.4%
Taylor expanded in maxCos around 0 98.3%
mul-1-neg98.3%
+-commutative98.3%
*-commutative98.3%
sub-neg98.3%
unpow298.3%
distribute-lft-out--98.2%
Simplified98.2%
if 4.99999999e-7 < maxCos Initial program 35.3%
Taylor expanded in ux around 0 88.6%
*-commutative88.6%
Simplified88.6%
Final simplification97.2%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* PI (* 2.0 uy))) (sqrt (* ux (- 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
return sinf((((float) M_PI) * (2.0f * uy))) * sqrtf((ux * (2.0f - ux)));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy))) * sqrt(Float32(ux * Float32(Float32(2.0) - ux)))) end
function tmp = code(ux, uy, maxCos) tmp = sin((single(pi) * (single(2.0) * uy))) * sqrt((ux * (single(2.0) - ux))); end
\begin{array}{l}
\\
\sin \left(\pi \cdot \left(2 \cdot uy\right)\right) \cdot \sqrt{ux \cdot \left(2 - ux\right)}
\end{array}
Initial program 55.7%
associate-*l*55.7%
sub-neg55.7%
+-commutative55.7%
distribute-rgt-neg-in55.7%
fma-def55.9%
Simplified55.9%
Taylor expanded in ux around 0 98.3%
fma-def98.4%
+-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
distribute-lft-in98.4%
metadata-eval98.4%
associate--l+98.4%
mul-1-neg98.4%
sub-neg98.4%
*-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in uy around inf 98.4%
*-commutative98.4%
fma-def98.4%
cancel-sign-sub-inv98.4%
metadata-eval98.4%
*-commutative98.4%
*-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
associate-*r*98.4%
Simplified98.4%
Taylor expanded in maxCos around 0 94.0%
mul-1-neg94.0%
+-commutative94.0%
*-commutative94.0%
sub-neg94.0%
unpow294.0%
distribute-lft-out--93.9%
Simplified93.9%
Final simplification93.9%
(FPCore (ux uy maxCos) :precision binary32 (* (* 2.0 (* uy PI)) (sqrt (* ux (- 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
return (2.0f * (uy * ((float) M_PI))) * sqrtf((ux * (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) - ux)))) end
function tmp = code(ux, uy, maxCos) tmp = (single(2.0) * (uy * single(pi))) * sqrt((ux * (single(2.0) - ux))); end
\begin{array}{l}
\\
\left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(2 - ux\right)}
\end{array}
Initial program 55.7%
associate-*l*55.7%
sub-neg55.7%
+-commutative55.7%
distribute-rgt-neg-in55.7%
fma-def55.9%
Simplified55.9%
Taylor expanded in ux around 0 98.3%
fma-def98.4%
+-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
distribute-lft-in98.4%
metadata-eval98.4%
associate--l+98.4%
mul-1-neg98.4%
sub-neg98.4%
*-commutative98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Taylor expanded in maxCos around 0 94.0%
associate-*r*94.0%
+-commutative94.0%
neg-mul-194.0%
unsub-neg94.0%
Simplified94.0%
add-exp-log91.1%
*-commutative91.1%
Applied egg-rr91.1%
Taylor expanded in uy around 0 79.0%
associate-*r*79.0%
*-commutative79.0%
unpow279.0%
distribute-lft-out--79.0%
Simplified79.0%
Final simplification79.0%
(FPCore (ux uy maxCos) :precision binary32 (* (* 2.0 (* uy PI)) (sqrt (* ux 2.0))))
float code(float ux, float uy, float maxCos) {
return (2.0f * (uy * ((float) M_PI))) * sqrtf((ux * 2.0f));
}
function code(ux, uy, maxCos) return Float32(Float32(Float32(2.0) * Float32(uy * Float32(pi))) * sqrt(Float32(ux * Float32(2.0)))) end
function tmp = code(ux, uy, maxCos) tmp = (single(2.0) * (uy * single(pi))) * sqrt((ux * single(2.0))); end
\begin{array}{l}
\\
\left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{ux \cdot 2}
\end{array}
Initial program 55.7%
associate-*l*55.7%
sub-neg55.7%
+-commutative55.7%
distribute-rgt-neg-in55.7%
fma-def55.9%
Simplified55.9%
Taylor expanded in uy around 0 48.8%
Simplified48.9%
Taylor expanded in ux around 0 67.0%
Taylor expanded in maxCos around 0 64.4%
*-commutative64.4%
Simplified64.4%
Final simplification64.4%
herbie shell --seed 2023320
(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)))))))