
(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 9 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 (* (sqrt (* ux (+ 2.0 (- (* (* ux (- 1.0 maxCos)) (+ maxCos -1.0)) (* 2.0 maxCos))))) (sin (* 2.0 (* uy PI)))))
float code(float ux, float uy, float maxCos) {
return sqrtf((ux * (2.0f + (((ux * (1.0f - maxCos)) * (maxCos + -1.0f)) - (2.0f * maxCos))))) * sinf((2.0f * (uy * ((float) M_PI))));
}
function code(ux, uy, maxCos) return Float32(sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(Float32(ux * Float32(Float32(1.0) - maxCos)) * Float32(maxCos + Float32(-1.0))) - Float32(Float32(2.0) * maxCos))))) * sin(Float32(Float32(2.0) * Float32(uy * Float32(pi))))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((ux * (single(2.0) + (((ux * (single(1.0) - maxCos)) * (maxCos + single(-1.0))) - (single(2.0) * maxCos))))) * sin((single(2.0) * (uy * single(pi)))); end
\begin{array}{l}
\\
\sqrt{ux \cdot \left(2 + \left(\left(ux \cdot \left(1 - maxCos\right)\right) \cdot \left(maxCos + -1\right) - 2 \cdot maxCos\right)\right)} \cdot \sin \left(2 \cdot \left(uy \cdot \pi\right)\right)
\end{array}
Initial program 58.1%
associate-*l*58.1%
sub-neg58.1%
+-commutative58.1%
distribute-rgt-neg-in58.1%
fma-define58.2%
Simplified58.5%
Taylor expanded in uy around inf 58.2%
Simplified58.3%
Taylor expanded in ux around -inf 98.3%
sub-neg98.3%
+-commutative98.3%
mul-1-neg98.3%
unsub-neg98.3%
+-commutative98.3%
mul-1-neg98.3%
unsub-neg98.3%
sub-neg98.3%
metadata-eval98.3%
+-commutative98.3%
mul-1-neg98.3%
remove-double-neg98.3%
*-commutative98.3%
Simplified98.3%
Taylor expanded in ux around 0 98.3%
associate--l+98.4%
associate-*r*98.4%
sub-neg98.4%
metadata-eval98.4%
Simplified98.4%
(FPCore (ux uy maxCos)
:precision binary32
(*
ux
(*
(sin (* 2.0 (* uy PI)))
(sqrt
(+ (* (- 1.0 maxCos) (+ maxCos -1.0)) (/ (- 2.0 (* 2.0 maxCos)) ux))))))
float code(float ux, float uy, float maxCos) {
return ux * (sinf((2.0f * (uy * ((float) M_PI)))) * sqrtf((((1.0f - maxCos) * (maxCos + -1.0f)) + ((2.0f - (2.0f * maxCos)) / ux))));
}
function code(ux, uy, maxCos) return Float32(ux * Float32(sin(Float32(Float32(2.0) * Float32(uy * Float32(pi)))) * sqrt(Float32(Float32(Float32(Float32(1.0) - maxCos) * Float32(maxCos + Float32(-1.0))) + Float32(Float32(Float32(2.0) - Float32(Float32(2.0) * maxCos)) / ux))))) end
function tmp = code(ux, uy, maxCos) tmp = ux * (sin((single(2.0) * (uy * single(pi)))) * sqrt((((single(1.0) - maxCos) * (maxCos + single(-1.0))) + ((single(2.0) - (single(2.0) * maxCos)) / ux)))); end
\begin{array}{l}
\\
ux \cdot \left(\sin \left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{\left(1 - maxCos\right) \cdot \left(maxCos + -1\right) + \frac{2 - 2 \cdot maxCos}{ux}}\right)
\end{array}
Initial program 58.1%
associate-*l*58.1%
sub-neg58.1%
+-commutative58.1%
distribute-rgt-neg-in58.1%
fma-define58.2%
Simplified58.5%
Taylor expanded in uy around inf 58.2%
Simplified58.3%
Taylor expanded in ux around -inf 98.3%
sub-neg98.3%
+-commutative98.3%
mul-1-neg98.3%
unsub-neg98.3%
+-commutative98.3%
mul-1-neg98.3%
unsub-neg98.3%
sub-neg98.3%
metadata-eval98.3%
+-commutative98.3%
mul-1-neg98.3%
remove-double-neg98.3%
*-commutative98.3%
Simplified98.3%
Taylor expanded in uy around inf 98.2%
associate-*l*98.0%
+-commutative98.0%
associate--l+98.0%
associate-*r/98.0%
metadata-eval98.0%
associate-*r/98.0%
div-sub98.1%
sub-neg98.1%
metadata-eval98.1%
Simplified98.1%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* 2.0 (* uy PI))) (sqrt (* ux (- 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
return sinf((2.0f * (uy * ((float) M_PI)))) * sqrtf((ux * (2.0f - ux)));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(2.0) * Float32(uy * Float32(pi)))) * sqrt(Float32(ux * Float32(Float32(2.0) - ux)))) end
function tmp = code(ux, uy, maxCos) tmp = sin((single(2.0) * (uy * single(pi)))) * sqrt((ux * (single(2.0) - ux))); end
\begin{array}{l}
\\
\sin \left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(2 - ux\right)}
\end{array}
Initial program 58.1%
associate-*l*58.1%
sub-neg58.1%
+-commutative58.1%
distribute-rgt-neg-in58.1%
fma-define58.2%
Simplified58.5%
Taylor expanded in ux around 0 98.4%
Taylor expanded in maxCos around 0 93.6%
*-commutative93.6%
mul-1-neg93.6%
unsub-neg93.6%
Simplified93.6%
(FPCore (ux uy maxCos)
:precision binary32
(*
2.0
(*
(* ux (* uy PI))
(sqrt
(-
(+ (* (- 1.0 maxCos) (+ maxCos -1.0)) (* 2.0 (/ 1.0 ux)))
(* 2.0 (/ maxCos ux)))))))
float code(float ux, float uy, float maxCos) {
return 2.0f * ((ux * (uy * ((float) M_PI))) * sqrtf(((((1.0f - maxCos) * (maxCos + -1.0f)) + (2.0f * (1.0f / ux))) - (2.0f * (maxCos / ux)))));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(Float32(ux * Float32(uy * Float32(pi))) * sqrt(Float32(Float32(Float32(Float32(Float32(1.0) - maxCos) * Float32(maxCos + Float32(-1.0))) + Float32(Float32(2.0) * Float32(Float32(1.0) / ux))) - Float32(Float32(2.0) * Float32(maxCos / ux)))))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * ((ux * (uy * single(pi))) * sqrt(((((single(1.0) - maxCos) * (maxCos + single(-1.0))) + (single(2.0) * (single(1.0) / ux))) - (single(2.0) * (maxCos / ux))))); end
\begin{array}{l}
\\
2 \cdot \left(\left(ux \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{\left(\left(1 - maxCos\right) \cdot \left(maxCos + -1\right) + 2 \cdot \frac{1}{ux}\right) - 2 \cdot \frac{maxCos}{ux}}\right)
\end{array}
Initial program 58.1%
associate-*l*58.1%
sub-neg58.1%
+-commutative58.1%
distribute-rgt-neg-in58.1%
fma-define58.2%
Simplified58.5%
Taylor expanded in uy around inf 58.2%
Simplified58.3%
Taylor expanded in ux around -inf 98.3%
sub-neg98.3%
+-commutative98.3%
mul-1-neg98.3%
unsub-neg98.3%
+-commutative98.3%
mul-1-neg98.3%
unsub-neg98.3%
sub-neg98.3%
metadata-eval98.3%
+-commutative98.3%
mul-1-neg98.3%
remove-double-neg98.3%
*-commutative98.3%
Simplified98.3%
Taylor expanded in uy around 0 83.0%
Final simplification83.0%
(FPCore (ux uy maxCos)
:precision binary32
(*
2.0
(*
ux
(*
(* uy PI)
(sqrt
(+ (* (- 1.0 maxCos) (+ maxCos -1.0)) (/ (- 2.0 (* 2.0 maxCos)) ux)))))))
float code(float ux, float uy, float maxCos) {
return 2.0f * (ux * ((uy * ((float) M_PI)) * sqrtf((((1.0f - maxCos) * (maxCos + -1.0f)) + ((2.0f - (2.0f * maxCos)) / ux)))));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(ux * Float32(Float32(uy * Float32(pi)) * sqrt(Float32(Float32(Float32(Float32(1.0) - maxCos) * Float32(maxCos + Float32(-1.0))) + Float32(Float32(Float32(2.0) - Float32(Float32(2.0) * maxCos)) / ux)))))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * (ux * ((uy * single(pi)) * sqrt((((single(1.0) - maxCos) * (maxCos + single(-1.0))) + ((single(2.0) - (single(2.0) * maxCos)) / ux))))); end
\begin{array}{l}
\\
2 \cdot \left(ux \cdot \left(\left(uy \cdot \pi\right) \cdot \sqrt{\left(1 - maxCos\right) \cdot \left(maxCos + -1\right) + \frac{2 - 2 \cdot maxCos}{ux}}\right)\right)
\end{array}
Initial program 58.1%
associate-*l*58.1%
sub-neg58.1%
+-commutative58.1%
distribute-rgt-neg-in58.1%
fma-define58.2%
Simplified58.5%
Taylor expanded in uy around inf 58.2%
Simplified58.3%
Taylor expanded in ux around -inf 98.3%
sub-neg98.3%
+-commutative98.3%
mul-1-neg98.3%
unsub-neg98.3%
+-commutative98.3%
mul-1-neg98.3%
unsub-neg98.3%
sub-neg98.3%
metadata-eval98.3%
+-commutative98.3%
mul-1-neg98.3%
remove-double-neg98.3%
*-commutative98.3%
Simplified98.3%
Taylor expanded in uy around 0 83.0%
associate-*l*82.8%
+-commutative82.8%
associate--l+82.8%
associate-*r/82.8%
metadata-eval82.8%
associate-*r/82.8%
div-sub82.9%
sub-neg82.9%
metadata-eval82.9%
Simplified82.9%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* (* ux (* uy PI)) (sqrt (+ -1.0 (/ 2.0 ux))))))
float code(float ux, float uy, float maxCos) {
return 2.0f * ((ux * (uy * ((float) M_PI))) * sqrtf((-1.0f + (2.0f / ux))));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(Float32(ux * Float32(uy * Float32(pi))) * sqrt(Float32(Float32(-1.0) + Float32(Float32(2.0) / ux))))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * ((ux * (uy * single(pi))) * sqrt((single(-1.0) + (single(2.0) / ux)))); end
\begin{array}{l}
\\
2 \cdot \left(\left(ux \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{-1 + \frac{2}{ux}}\right)
\end{array}
Initial program 58.1%
Taylor expanded in ux around inf 98.2%
Taylor expanded in maxCos around 0 93.5%
Taylor expanded in uy around 0 79.8%
associate-*l*79.7%
sub-neg79.7%
metadata-eval79.7%
+-commutative79.7%
associate-*r/79.7%
metadata-eval79.7%
Simplified79.7%
Taylor expanded in uy around 0 79.8%
*-commutative79.8%
sub-neg79.8%
metadata-eval79.8%
+-commutative79.8%
associate-*r/79.8%
metadata-eval79.8%
metadata-eval79.8%
associate-*r/79.8%
+-commutative79.8%
associate-*r/79.8%
metadata-eval79.8%
Simplified79.8%
Final simplification79.8%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* ux (* uy (* PI (sqrt (+ -1.0 (/ 2.0 ux))))))))
float code(float ux, float uy, float maxCos) {
return 2.0f * (ux * (uy * (((float) M_PI) * sqrtf((-1.0f + (2.0f / ux))))));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(ux * Float32(uy * Float32(Float32(pi) * sqrt(Float32(Float32(-1.0) + Float32(Float32(2.0) / ux))))))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * (ux * (uy * (single(pi) * sqrt((single(-1.0) + (single(2.0) / ux)))))); end
\begin{array}{l}
\\
2 \cdot \left(ux \cdot \left(uy \cdot \left(\pi \cdot \sqrt{-1 + \frac{2}{ux}}\right)\right)\right)
\end{array}
Initial program 58.1%
Taylor expanded in ux around inf 98.2%
Taylor expanded in maxCos around 0 93.5%
Taylor expanded in uy around 0 79.8%
associate-*l*79.7%
sub-neg79.7%
metadata-eval79.7%
+-commutative79.7%
associate-*r/79.7%
metadata-eval79.7%
Simplified79.7%
Taylor expanded in uy around 0 79.7%
sub-neg79.7%
metadata-eval79.7%
+-commutative79.7%
associate-*r/79.7%
metadata-eval79.7%
associate-*l*79.7%
metadata-eval79.7%
associate-*r/79.7%
+-commutative79.7%
associate-*r/79.7%
metadata-eval79.7%
Simplified79.7%
Final simplification79.7%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* ux (* uy (* PI (sqrt -1.0))))))
float code(float ux, float uy, float maxCos) {
return 2.0f * (ux * (uy * (((float) M_PI) * sqrtf(-1.0f))));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(ux * Float32(uy * Float32(Float32(pi) * sqrt(Float32(-1.0)))))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * (ux * (uy * (single(pi) * sqrt(single(-1.0))))); end
\begin{array}{l}
\\
2 \cdot \left(ux \cdot \left(uy \cdot \left(\pi \cdot \sqrt{-1}\right)\right)\right)
\end{array}
Initial program 58.1%
Taylor expanded in ux around inf 98.2%
Taylor expanded in maxCos around 0 93.5%
Taylor expanded in uy around 0 79.8%
associate-*l*79.7%
sub-neg79.7%
metadata-eval79.7%
+-commutative79.7%
associate-*r/79.7%
metadata-eval79.7%
Simplified79.7%
Taylor expanded in ux around inf -0.0%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* uy (* PI (sqrt 0.0)))))
float code(float ux, float uy, float maxCos) {
return 2.0f * (uy * (((float) M_PI) * sqrtf(0.0f)));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(uy * Float32(Float32(pi) * sqrt(Float32(0.0))))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * (uy * (single(pi) * sqrt(single(0.0)))); end
\begin{array}{l}
\\
2 \cdot \left(uy \cdot \left(\pi \cdot \sqrt{0}\right)\right)
\end{array}
Initial program 58.1%
associate-*l*58.1%
sub-neg58.1%
+-commutative58.1%
distribute-rgt-neg-in58.1%
fma-define58.2%
Simplified58.5%
Taylor expanded in uy around 0 52.5%
Simplified52.6%
Taylor expanded in ux around 0 7.1%
Final simplification7.1%
herbie shell --seed 2024108
(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)))))))