
(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
(*
(sin (* uy (* 2.0 PI)))
(sqrt
(*
ux
(-
(+
1.0
(+
(* maxCos (+ (/ 1.0 maxCos) -1.0))
(* ux (* (- 1.0 maxCos) (+ maxCos -1.0)))))
maxCos)))))
float code(float ux, float uy, float maxCos) {
return sinf((uy * (2.0f * ((float) M_PI)))) * sqrtf((ux * ((1.0f + ((maxCos * ((1.0f / maxCos) + -1.0f)) + (ux * ((1.0f - maxCos) * (maxCos + -1.0f))))) - maxCos)));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(ux * Float32(Float32(Float32(1.0) + Float32(Float32(maxCos * Float32(Float32(Float32(1.0) / maxCos) + Float32(-1.0))) + Float32(ux * Float32(Float32(Float32(1.0) - maxCos) * Float32(maxCos + Float32(-1.0)))))) - maxCos)))) end
function tmp = code(ux, uy, maxCos) tmp = sin((uy * (single(2.0) * single(pi)))) * sqrt((ux * ((single(1.0) + ((maxCos * ((single(1.0) / maxCos) + single(-1.0))) + (ux * ((single(1.0) - maxCos) * (maxCos + single(-1.0)))))) - maxCos))); end
\begin{array}{l}
\\
\sin \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(\left(1 + \left(maxCos \cdot \left(\frac{1}{maxCos} + -1\right) + ux \cdot \left(\left(1 - maxCos\right) \cdot \left(maxCos + -1\right)\right)\right)\right) - maxCos\right)}
\end{array}
Initial program 54.3%
associate-*l*54.3%
sub-neg54.3%
+-commutative54.3%
distribute-rgt-neg-in54.3%
fma-define54.3%
Simplified54.4%
Taylor expanded in ux around inf 98.3%
Taylor expanded in maxCos around inf 88.7%
Taylor expanded in ux around 0 98.5%
Final simplification98.5%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sin (* uy (* 2.0 PI)))
(sqrt
(*
ux
(+
1.0
(-
(+ (- 1.0 maxCos) (* (* ux (- 1.0 maxCos)) (+ maxCos -1.0)))
maxCos))))))
float code(float ux, float uy, float maxCos) {
return sinf((uy * (2.0f * ((float) M_PI)))) * sqrtf((ux * (1.0f + (((1.0f - maxCos) + ((ux * (1.0f - maxCos)) * (maxCos + -1.0f))) - maxCos))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(ux * Float32(Float32(1.0) + Float32(Float32(Float32(Float32(1.0) - maxCos) + Float32(Float32(ux * Float32(Float32(1.0) - maxCos)) * Float32(maxCos + Float32(-1.0)))) - maxCos))))) end
function tmp = code(ux, uy, maxCos) tmp = sin((uy * (single(2.0) * single(pi)))) * sqrt((ux * (single(1.0) + (((single(1.0) - maxCos) + ((ux * (single(1.0) - maxCos)) * (maxCos + single(-1.0)))) - maxCos)))); end
\begin{array}{l}
\\
\sin \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(1 + \left(\left(\left(1 - maxCos\right) + \left(ux \cdot \left(1 - maxCos\right)\right) \cdot \left(maxCos + -1\right)\right) - maxCos\right)\right)}
\end{array}
Initial program 54.3%
associate-*l*54.3%
sub-neg54.3%
+-commutative54.3%
distribute-rgt-neg-in54.3%
fma-define54.3%
Simplified54.4%
Taylor expanded in ux around inf 98.3%
Taylor expanded in ux around 0 98.5%
associate--l+98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
distribute-lft-in98.4%
metadata-eval98.4%
neg-mul-198.4%
sub-neg98.4%
associate-*r*98.4%
sub-neg98.4%
metadata-eval98.4%
Simplified98.4%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sin (* uy (* 2.0 PI)))
(sqrt
(*
ux
(- (+ 2.0 (* ux (* (- 1.0 maxCos) (+ maxCos -1.0)))) (* 2.0 maxCos))))))
float code(float ux, float uy, float maxCos) {
return sinf((uy * (2.0f * ((float) M_PI)))) * sqrtf((ux * ((2.0f + (ux * ((1.0f - maxCos) * (maxCos + -1.0f)))) - (2.0f * maxCos))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(ux * Float32(Float32(Float32(2.0) + Float32(ux * Float32(Float32(Float32(1.0) - maxCos) * Float32(maxCos + Float32(-1.0))))) - Float32(Float32(2.0) * maxCos))))) end
function tmp = code(ux, uy, maxCos) tmp = sin((uy * (single(2.0) * single(pi)))) * sqrt((ux * ((single(2.0) + (ux * ((single(1.0) - maxCos) * (maxCos + single(-1.0))))) - (single(2.0) * maxCos)))); end
\begin{array}{l}
\\
\sin \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(\left(2 + ux \cdot \left(\left(1 - maxCos\right) \cdot \left(maxCos + -1\right)\right)\right) - 2 \cdot maxCos\right)}
\end{array}
Initial program 54.3%
associate-*l*54.3%
sub-neg54.3%
+-commutative54.3%
distribute-rgt-neg-in54.3%
fma-define54.3%
Simplified54.4%
Taylor expanded in ux around inf 98.3%
Taylor expanded in maxCos around 0 98.3%
+-commutative98.3%
mul-1-neg98.3%
unsub-neg98.3%
div-sub98.3%
Simplified98.3%
Taylor expanded in ux around 0 98.4%
Final simplification98.4%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* PI (* uy 2.0))) (sqrt (* ux (+ 2.0 (- (* maxCos (- (* 2.0 ux) 2.0)) ux))))))
float code(float ux, float uy, float maxCos) {
return sinf((((float) M_PI) * (uy * 2.0f))) * sqrtf((ux * (2.0f + ((maxCos * ((2.0f * ux) - 2.0f)) - ux))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(pi) * Float32(uy * Float32(2.0)))) * 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((single(pi) * (uy * single(2.0)))) * sqrt((ux * (single(2.0) + ((maxCos * ((single(2.0) * ux) - single(2.0))) - ux)))); end
\begin{array}{l}
\\
\sin \left(\pi \cdot \left(uy \cdot 2\right)\right) \cdot \sqrt{ux \cdot \left(2 + \left(maxCos \cdot \left(2 \cdot ux - 2\right) - ux\right)\right)}
\end{array}
Initial program 54.3%
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 97.6%
Final simplification97.6%
(FPCore (ux uy maxCos)
:precision binary32
(let* ((t_0 (* PI (* uy 2.0))))
(if (<= (* uy 2.0) 0.0003000000142492354)
(*
(sqrt
(*
ux
(+
1.0
(-
(+ (- 1.0 maxCos) (* (* ux (- 1.0 maxCos)) (+ maxCos -1.0)))
maxCos))))
t_0)
(* (sin t_0) (sqrt (* ux (- 2.0 ux)))))))
float code(float ux, float uy, float maxCos) {
float t_0 = ((float) M_PI) * (uy * 2.0f);
float tmp;
if ((uy * 2.0f) <= 0.0003000000142492354f) {
tmp = sqrtf((ux * (1.0f + (((1.0f - maxCos) + ((ux * (1.0f - maxCos)) * (maxCos + -1.0f))) - maxCos)))) * t_0;
} else {
tmp = sinf(t_0) * sqrtf((ux * (2.0f - ux)));
}
return tmp;
}
function code(ux, uy, maxCos) t_0 = Float32(Float32(pi) * Float32(uy * Float32(2.0))) tmp = Float32(0.0) if (Float32(uy * Float32(2.0)) <= Float32(0.0003000000142492354)) tmp = Float32(sqrt(Float32(ux * Float32(Float32(1.0) + Float32(Float32(Float32(Float32(1.0) - maxCos) + Float32(Float32(ux * Float32(Float32(1.0) - maxCos)) * Float32(maxCos + Float32(-1.0)))) - maxCos)))) * t_0); else tmp = Float32(sin(t_0) * sqrt(Float32(ux * Float32(Float32(2.0) - ux)))); end return tmp end
function tmp_2 = code(ux, uy, maxCos) t_0 = single(pi) * (uy * single(2.0)); tmp = single(0.0); if ((uy * single(2.0)) <= single(0.0003000000142492354)) tmp = sqrt((ux * (single(1.0) + (((single(1.0) - maxCos) + ((ux * (single(1.0) - maxCos)) * (maxCos + single(-1.0)))) - maxCos)))) * t_0; else tmp = sin(t_0) * sqrt((ux * (single(2.0) - ux))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \pi \cdot \left(uy \cdot 2\right)\\
\mathbf{if}\;uy \cdot 2 \leq 0.0003000000142492354:\\
\;\;\;\;\sqrt{ux \cdot \left(1 + \left(\left(\left(1 - maxCos\right) + \left(ux \cdot \left(1 - maxCos\right)\right) \cdot \left(maxCos + -1\right)\right) - maxCos\right)\right)} \cdot t\_0\\
\mathbf{else}:\\
\;\;\;\;\sin t\_0 \cdot \sqrt{ux \cdot \left(2 - ux\right)}\\
\end{array}
\end{array}
if (*.f32 uy #s(literal 2 binary32)) < 3.00000014e-4Initial program 54.3%
associate-*l*54.3%
sub-neg54.3%
+-commutative54.3%
distribute-rgt-neg-in54.3%
fma-define54.5%
Simplified54.5%
Taylor expanded in ux around inf 98.4%
Taylor expanded in ux around 0 98.7%
associate--l+98.6%
sub-neg98.6%
metadata-eval98.6%
+-commutative98.6%
distribute-lft-in98.6%
metadata-eval98.6%
neg-mul-198.6%
sub-neg98.6%
associate-*r*98.6%
sub-neg98.6%
metadata-eval98.6%
Simplified98.6%
Taylor expanded in uy around 0 98.4%
associate-*r*98.4%
Simplified98.4%
if 3.00000014e-4 < (*.f32 uy #s(literal 2 binary32)) Initial program 54.2%
Taylor expanded in ux around 0 98.1%
associate--l+98.1%
associate-*r*98.1%
mul-1-neg98.1%
sub-neg98.1%
metadata-eval98.1%
+-commutative98.1%
Simplified98.1%
Taylor expanded in maxCos around 0 92.3%
neg-mul-192.3%
unsub-neg92.3%
Simplified92.3%
Final simplification96.2%
(FPCore (ux uy maxCos)
:precision binary32
(if (<= (* uy 2.0) 0.01600000075995922)
(*
(sqrt
(*
ux
(+
1.0
(-
(+ (- 1.0 maxCos) (* (* ux (- 1.0 maxCos)) (+ maxCos -1.0)))
maxCos))))
(* PI (* uy 2.0)))
(* (sin (* uy (* 2.0 PI))) (sqrt (* 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
float tmp;
if ((uy * 2.0f) <= 0.01600000075995922f) {
tmp = sqrtf((ux * (1.0f + (((1.0f - maxCos) + ((ux * (1.0f - maxCos)) * (maxCos + -1.0f))) - maxCos)))) * (((float) M_PI) * (uy * 2.0f));
} else {
tmp = sinf((uy * (2.0f * ((float) M_PI)))) * sqrtf((2.0f * ux));
}
return tmp;
}
function code(ux, uy, maxCos) tmp = Float32(0.0) if (Float32(uy * Float32(2.0)) <= Float32(0.01600000075995922)) tmp = Float32(sqrt(Float32(ux * Float32(Float32(1.0) + Float32(Float32(Float32(Float32(1.0) - maxCos) + Float32(Float32(ux * Float32(Float32(1.0) - maxCos)) * Float32(maxCos + Float32(-1.0)))) - maxCos)))) * Float32(Float32(pi) * Float32(uy * Float32(2.0)))); else tmp = Float32(sin(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(Float32(2.0) * ux))); end return tmp end
function tmp_2 = code(ux, uy, maxCos) tmp = single(0.0); if ((uy * single(2.0)) <= single(0.01600000075995922)) tmp = sqrt((ux * (single(1.0) + (((single(1.0) - maxCos) + ((ux * (single(1.0) - maxCos)) * (maxCos + single(-1.0)))) - maxCos)))) * (single(pi) * (uy * single(2.0))); else tmp = sin((uy * (single(2.0) * single(pi)))) * sqrt((single(2.0) * ux)); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;uy \cdot 2 \leq 0.01600000075995922:\\
\;\;\;\;\sqrt{ux \cdot \left(1 + \left(\left(\left(1 - maxCos\right) + \left(ux \cdot \left(1 - maxCos\right)\right) \cdot \left(maxCos + -1\right)\right) - maxCos\right)\right)} \cdot \left(\pi \cdot \left(uy \cdot 2\right)\right)\\
\mathbf{else}:\\
\;\;\;\;\sin \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{2 \cdot ux}\\
\end{array}
\end{array}
if (*.f32 uy #s(literal 2 binary32)) < 0.0160000008Initial program 56.2%
associate-*l*56.2%
sub-neg56.2%
+-commutative56.2%
distribute-rgt-neg-in56.2%
fma-define56.3%
Simplified56.4%
Taylor expanded in ux around inf 98.3%
Taylor expanded in ux around 0 98.6%
associate--l+98.5%
sub-neg98.5%
metadata-eval98.5%
+-commutative98.5%
distribute-lft-in98.5%
metadata-eval98.5%
neg-mul-198.5%
sub-neg98.5%
associate-*r*98.5%
sub-neg98.5%
metadata-eval98.5%
Simplified98.5%
Taylor expanded in uy around 0 95.5%
associate-*r*95.5%
Simplified95.5%
if 0.0160000008 < (*.f32 uy #s(literal 2 binary32)) Initial program 47.9%
associate-*l*47.9%
sub-neg47.9%
+-commutative47.9%
distribute-rgt-neg-in47.9%
fma-define47.8%
Simplified48.0%
Taylor expanded in maxCos around 0 47.5%
Taylor expanded in ux around 0 77.0%
*-commutative77.0%
Simplified77.0%
Final simplification91.2%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sqrt
(*
ux
(+
1.0
(- (+ (- 1.0 maxCos) (* (* ux (- 1.0 maxCos)) (+ maxCos -1.0))) maxCos))))
(* PI (* uy 2.0))))
float code(float ux, float uy, float maxCos) {
return sqrtf((ux * (1.0f + (((1.0f - maxCos) + ((ux * (1.0f - maxCos)) * (maxCos + -1.0f))) - maxCos)))) * (((float) M_PI) * (uy * 2.0f));
}
function code(ux, uy, maxCos) return Float32(sqrt(Float32(ux * Float32(Float32(1.0) + Float32(Float32(Float32(Float32(1.0) - maxCos) + Float32(Float32(ux * Float32(Float32(1.0) - maxCos)) * Float32(maxCos + Float32(-1.0)))) - maxCos)))) * Float32(Float32(pi) * Float32(uy * Float32(2.0)))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((ux * (single(1.0) + (((single(1.0) - maxCos) + ((ux * (single(1.0) - maxCos)) * (maxCos + single(-1.0)))) - maxCos)))) * (single(pi) * (uy * single(2.0))); end
\begin{array}{l}
\\
\sqrt{ux \cdot \left(1 + \left(\left(\left(1 - maxCos\right) + \left(ux \cdot \left(1 - maxCos\right)\right) \cdot \left(maxCos + -1\right)\right) - maxCos\right)\right)} \cdot \left(\pi \cdot \left(uy \cdot 2\right)\right)
\end{array}
Initial program 54.3%
associate-*l*54.3%
sub-neg54.3%
+-commutative54.3%
distribute-rgt-neg-in54.3%
fma-define54.3%
Simplified54.4%
Taylor expanded in ux around inf 98.3%
Taylor expanded in ux around 0 98.5%
associate--l+98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
distribute-lft-in98.4%
metadata-eval98.4%
neg-mul-198.4%
sub-neg98.4%
associate-*r*98.4%
sub-neg98.4%
metadata-eval98.4%
Simplified98.4%
Taylor expanded in uy around 0 82.2%
associate-*r*82.2%
Simplified82.2%
Final simplification82.2%
(FPCore (ux uy maxCos) :precision binary32 (* (* uy 2.0) (* PI (sqrt (* ux (- 2.0 ux))))))
float code(float ux, float uy, float maxCos) {
return (uy * 2.0f) * (((float) M_PI) * sqrtf((ux * (2.0f - ux))));
}
function code(ux, uy, maxCos) return Float32(Float32(uy * Float32(2.0)) * Float32(Float32(pi) * sqrt(Float32(ux * Float32(Float32(2.0) - ux))))) end
function tmp = code(ux, uy, maxCos) tmp = (uy * single(2.0)) * (single(pi) * sqrt((ux * (single(2.0) - ux)))); end
\begin{array}{l}
\\
\left(uy \cdot 2\right) \cdot \left(\pi \cdot \sqrt{ux \cdot \left(2 - ux\right)}\right)
\end{array}
Initial program 54.3%
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 92.6%
neg-mul-192.6%
unsub-neg92.6%
Simplified92.6%
Taylor expanded in uy around 0 78.1%
associate-*r*78.1%
Simplified78.1%
pow178.1%
associate-*l*78.1%
Applied egg-rr78.1%
unpow178.1%
*-commutative78.1%
Simplified78.1%
Final simplification78.1%
(FPCore (ux uy maxCos) :precision binary32 (* (* PI (* uy 2.0)) (sqrt (* 2.0 ux))))
float code(float ux, float uy, float maxCos) {
return (((float) M_PI) * (uy * 2.0f)) * sqrtf((2.0f * ux));
}
function code(ux, uy, maxCos) return Float32(Float32(Float32(pi) * Float32(uy * Float32(2.0))) * sqrt(Float32(Float32(2.0) * ux))) end
function tmp = code(ux, uy, maxCos) tmp = (single(pi) * (uy * single(2.0))) * sqrt((single(2.0) * ux)); end
\begin{array}{l}
\\
\left(\pi \cdot \left(uy \cdot 2\right)\right) \cdot \sqrt{2 \cdot ux}
\end{array}
Initial program 54.3%
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 92.6%
neg-mul-192.6%
unsub-neg92.6%
Simplified92.6%
Taylor expanded in uy around 0 78.1%
associate-*r*78.1%
Simplified78.1%
Taylor expanded in ux around 0 65.3%
Final simplification65.3%
herbie shell --seed 2024130
(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)))))))