
(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
(let* ((t_0 (sqrt (- 1.0 (+ maxCos (+ maxCos -1.0))))))
(*
(sin (cbrt (* (pow (* uy 2.0) 3.0) (pow PI 3.0))))
(sqrt
(+
(* (* (- 1.0 maxCos) (pow ux 2.0)) (+ maxCos -1.0))
(* ux (* t_0 t_0)))))))
float code(float ux, float uy, float maxCos) {
float t_0 = sqrtf((1.0f - (maxCos + (maxCos + -1.0f))));
return sinf(cbrtf((powf((uy * 2.0f), 3.0f) * powf(((float) M_PI), 3.0f)))) * sqrtf(((((1.0f - maxCos) * powf(ux, 2.0f)) * (maxCos + -1.0f)) + (ux * (t_0 * t_0))));
}
function code(ux, uy, maxCos) t_0 = sqrt(Float32(Float32(1.0) - Float32(maxCos + Float32(maxCos + Float32(-1.0))))) return Float32(sin(cbrt(Float32((Float32(uy * Float32(2.0)) ^ Float32(3.0)) * (Float32(pi) ^ Float32(3.0))))) * sqrt(Float32(Float32(Float32(Float32(Float32(1.0) - maxCos) * (ux ^ Float32(2.0))) * Float32(maxCos + Float32(-1.0))) + Float32(ux * Float32(t_0 * t_0))))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt{1 - \left(maxCos + \left(maxCos + -1\right)\right)}\\
\sin \left(\sqrt[3]{{\left(uy \cdot 2\right)}^{3} \cdot {\pi}^{3}}\right) \cdot \sqrt{\left(\left(1 - maxCos\right) \cdot {ux}^{2}\right) \cdot \left(maxCos + -1\right) + ux \cdot \left(t_0 \cdot t_0\right)}
\end{array}
\end{array}
Initial program 56.8%
associate-*l*56.8%
sub-neg56.8%
+-commutative56.8%
distribute-rgt-neg-in56.8%
fma-def57.0%
+-commutative57.0%
associate-+r-57.0%
fma-def57.0%
neg-sub057.0%
+-commutative57.0%
associate-+r-56.9%
associate--r-56.9%
neg-sub056.9%
+-commutative56.9%
sub-neg56.9%
fma-def56.9%
Simplified56.9%
Taylor expanded in ux around 0 98.2%
associate-*r*98.2%
add-cbrt-cube98.2%
add-cbrt-cube98.2%
cbrt-unprod98.2%
pow398.2%
pow398.2%
Applied egg-rr98.2%
add-sqr-sqrt98.4%
associate--l+98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
associate--l+98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
Applied egg-rr98.4%
Final simplification98.4%
(FPCore (ux uy maxCos)
:precision binary32
(expm1
(log1p
(*
(sin (* uy (* 2.0 PI)))
(sqrt
(fma
(+ maxCos -1.0)
(* (- 1.0 maxCos) (* ux ux))
(* ux (- (- 1.0 (+ maxCos -1.0)) maxCos))))))))
float code(float ux, float uy, float maxCos) {
return expm1f(log1pf((sinf((uy * (2.0f * ((float) M_PI)))) * sqrtf(fmaf((maxCos + -1.0f), ((1.0f - maxCos) * (ux * ux)), (ux * ((1.0f - (maxCos + -1.0f)) - maxCos)))))));
}
function code(ux, uy, maxCos) return expm1(log1p(Float32(sin(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(fma(Float32(maxCos + Float32(-1.0)), Float32(Float32(Float32(1.0) - maxCos) * Float32(ux * ux)), Float32(ux * Float32(Float32(Float32(1.0) - Float32(maxCos + Float32(-1.0))) - maxCos))))))) end
\begin{array}{l}
\\
\mathsf{expm1}\left(\mathsf{log1p}\left(\sin \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{\mathsf{fma}\left(maxCos + -1, \left(1 - maxCos\right) \cdot \left(ux \cdot ux\right), ux \cdot \left(\left(1 - \left(maxCos + -1\right)\right) - maxCos\right)\right)}\right)\right)
\end{array}
Initial program 56.8%
associate-*l*56.8%
sub-neg56.8%
+-commutative56.8%
distribute-rgt-neg-in56.8%
fma-def57.0%
+-commutative57.0%
associate-+r-57.0%
fma-def57.0%
neg-sub057.0%
+-commutative57.0%
associate-+r-56.9%
associate--r-56.9%
neg-sub056.9%
+-commutative56.9%
sub-neg56.9%
fma-def56.9%
Simplified56.9%
Taylor expanded in ux around 0 98.2%
expm1-log1p-u98.2%
*-commutative98.2%
fma-def98.2%
sub-neg98.2%
metadata-eval98.2%
unpow298.2%
mul-1-neg98.2%
sub-neg98.2%
metadata-eval98.2%
Applied egg-rr98.2%
Final simplification98.2%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sin (* uy (* 2.0 PI)))
(sqrt
(fma
ux
(+ 1.0 (- (- 1.0 maxCos) maxCos))
(* (+ maxCos -1.0) (* (- 1.0 maxCos) (* ux ux)))))))
float code(float ux, float uy, float maxCos) {
return sinf((uy * (2.0f * ((float) M_PI)))) * sqrtf(fmaf(ux, (1.0f + ((1.0f - maxCos) - maxCos)), ((maxCos + -1.0f) * ((1.0f - maxCos) * (ux * ux)))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(fma(ux, Float32(Float32(1.0) + Float32(Float32(Float32(1.0) - maxCos) - maxCos)), Float32(Float32(maxCos + Float32(-1.0)) * Float32(Float32(Float32(1.0) - maxCos) * Float32(ux * ux)))))) end
\begin{array}{l}
\\
\sin \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{\mathsf{fma}\left(ux, 1 + \left(\left(1 - maxCos\right) - maxCos\right), \left(maxCos + -1\right) \cdot \left(\left(1 - maxCos\right) \cdot \left(ux \cdot ux\right)\right)\right)}
\end{array}
Initial program 56.8%
associate-*l*56.8%
sub-neg56.8%
+-commutative56.8%
distribute-rgt-neg-in56.8%
fma-def57.0%
+-commutative57.0%
associate-+r-57.0%
fma-def57.0%
neg-sub057.0%
+-commutative57.0%
associate-+r-56.9%
associate--r-56.9%
neg-sub056.9%
+-commutative56.9%
sub-neg56.9%
fma-def56.9%
Simplified56.9%
Taylor expanded in ux around 0 98.2%
+-commutative98.2%
fma-def98.2%
associate--l+98.2%
mul-1-neg98.2%
sub-neg98.2%
metadata-eval98.2%
distribute-neg-in98.2%
metadata-eval98.2%
+-commutative98.2%
sub-neg98.2%
sub-neg98.2%
metadata-eval98.2%
*-commutative98.2%
unpow298.2%
Simplified98.2%
Final simplification98.2%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sin (* 2.0 (* uy PI)))
(sqrt
(fma
(+ maxCos -1.0)
(* (- 1.0 maxCos) (* ux ux))
(* ux (+ 1.0 (- (- 1.0 maxCos) maxCos)))))))
float code(float ux, float uy, float maxCos) {
return sinf((2.0f * (uy * ((float) M_PI)))) * sqrtf(fmaf((maxCos + -1.0f), ((1.0f - maxCos) * (ux * ux)), (ux * (1.0f + ((1.0f - maxCos) - maxCos)))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(2.0) * Float32(uy * Float32(pi)))) * sqrt(fma(Float32(maxCos + Float32(-1.0)), Float32(Float32(Float32(1.0) - maxCos) * Float32(ux * ux)), Float32(ux * Float32(Float32(1.0) + Float32(Float32(Float32(1.0) - maxCos) - maxCos)))))) end
\begin{array}{l}
\\
\sin \left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{\mathsf{fma}\left(maxCos + -1, \left(1 - maxCos\right) \cdot \left(ux \cdot ux\right), ux \cdot \left(1 + \left(\left(1 - maxCos\right) - maxCos\right)\right)\right)}
\end{array}
Initial program 56.8%
associate-*l*56.8%
sub-neg56.8%
+-commutative56.8%
distribute-rgt-neg-in56.8%
fma-def57.0%
+-commutative57.0%
associate-+r-57.0%
fma-def57.0%
neg-sub057.0%
+-commutative57.0%
associate-+r-56.9%
associate--r-56.9%
neg-sub056.9%
+-commutative56.9%
sub-neg56.9%
fma-def56.9%
Simplified56.9%
Taylor expanded in ux around 0 98.2%
Taylor expanded in uy around inf 98.2%
fma-def98.2%
sub-neg98.2%
metadata-eval98.2%
unpow298.2%
neg-mul-198.2%
associate--l+98.2%
neg-sub098.2%
associate--r-98.2%
neg-sub098.2%
+-commutative98.2%
sub-neg98.2%
Simplified98.2%
Final simplification98.2%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sqrt
(fma
(+ maxCos -1.0)
(* (- 1.0 maxCos) (* ux ux))
(* ux (- (- (- 1.0 maxCos) -1.0) maxCos))))
(sin (* 2.0 (* uy PI)))))
float code(float ux, float uy, float maxCos) {
return sqrtf(fmaf((maxCos + -1.0f), ((1.0f - maxCos) * (ux * ux)), (ux * (((1.0f - maxCos) - -1.0f) - maxCos)))) * sinf((2.0f * (uy * ((float) M_PI))));
}
function code(ux, uy, maxCos) return Float32(sqrt(fma(Float32(maxCos + Float32(-1.0)), Float32(Float32(Float32(1.0) - maxCos) * Float32(ux * ux)), Float32(ux * Float32(Float32(Float32(Float32(1.0) - maxCos) - Float32(-1.0)) - maxCos)))) * sin(Float32(Float32(2.0) * Float32(uy * Float32(pi))))) end
\begin{array}{l}
\\
\sqrt{\mathsf{fma}\left(maxCos + -1, \left(1 - maxCos\right) \cdot \left(ux \cdot ux\right), ux \cdot \left(\left(\left(1 - maxCos\right) - -1\right) - maxCos\right)\right)} \cdot \sin \left(2 \cdot \left(uy \cdot \pi\right)\right)
\end{array}
Initial program 56.8%
associate-*l*56.8%
sub-neg56.8%
+-commutative56.8%
distribute-rgt-neg-in56.8%
fma-def57.0%
+-commutative57.0%
associate-+r-57.0%
fma-def57.0%
neg-sub057.0%
+-commutative57.0%
associate-+r-56.9%
associate--r-56.9%
neg-sub056.9%
+-commutative56.9%
sub-neg56.9%
fma-def56.9%
Simplified56.9%
Taylor expanded in uy around inf 56.7%
*-un-lft-identity56.7%
associate--l+56.9%
Applied egg-rr56.9%
*-lft-identity56.9%
Simplified56.9%
Taylor expanded in ux around 0 98.2%
associate-*r*98.2%
*-commutative98.2%
associate-*r*98.2%
fma-def98.2%
sub-neg98.2%
metadata-eval98.2%
unpow298.2%
mul-1-neg98.2%
sub-neg98.2%
metadata-eval98.2%
sub-neg98.2%
associate--r+98.2%
Simplified98.2%
Final simplification98.2%
(FPCore (ux uy maxCos)
:precision binary32
(*
(sin (* 2.0 (* uy PI)))
(sqrt
(fma
ux
(- (- 2.0 maxCos) maxCos)
(* (+ maxCos -1.0) (* (- 1.0 maxCos) (* ux ux)))))))
float code(float ux, float uy, float maxCos) {
return sinf((2.0f * (uy * ((float) M_PI)))) * sqrtf(fmaf(ux, ((2.0f - maxCos) - maxCos), ((maxCos + -1.0f) * ((1.0f - maxCos) * (ux * ux)))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(2.0) * Float32(uy * Float32(pi)))) * sqrt(fma(ux, Float32(Float32(Float32(2.0) - maxCos) - maxCos), Float32(Float32(maxCos + Float32(-1.0)) * Float32(Float32(Float32(1.0) - maxCos) * Float32(ux * ux)))))) end
\begin{array}{l}
\\
\sin \left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{\mathsf{fma}\left(ux, \left(2 - maxCos\right) - maxCos, \left(maxCos + -1\right) \cdot \left(\left(1 - maxCos\right) \cdot \left(ux \cdot ux\right)\right)\right)}
\end{array}
Initial program 56.8%
associate-*l*56.8%
sub-neg56.8%
+-commutative56.8%
distribute-rgt-neg-in56.8%
fma-def57.0%
+-commutative57.0%
associate-+r-57.0%
fma-def57.0%
neg-sub057.0%
+-commutative57.0%
associate-+r-56.9%
associate--r-56.9%
neg-sub056.9%
+-commutative56.9%
sub-neg56.9%
fma-def56.9%
Simplified56.9%
Taylor expanded in uy around inf 56.7%
*-un-lft-identity56.7%
associate--l+56.9%
Applied egg-rr56.9%
*-lft-identity56.9%
Simplified56.9%
Taylor expanded in ux around 0 98.2%
+-commutative98.2%
fma-def98.2%
mul-1-neg98.2%
sub-neg98.2%
metadata-eval98.2%
sub-neg98.2%
+-commutative98.2%
associate--r+98.2%
metadata-eval98.2%
associate-*r*98.2%
*-commutative98.2%
associate-*r*98.2%
sub-neg98.2%
metadata-eval98.2%
unpow298.2%
Simplified98.2%
Final simplification98.2%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* 2.0 (* uy PI))) (sqrt (- (* 2.0 ux) (* ux ux)))))
float code(float ux, float uy, float maxCos) {
return sinf((2.0f * (uy * ((float) M_PI)))) * sqrtf(((2.0f * ux) - (ux * ux)));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(2.0) * Float32(uy * Float32(pi)))) * sqrt(Float32(Float32(Float32(2.0) * ux) - Float32(ux * ux)))) end
function tmp = code(ux, uy, maxCos) tmp = sin((single(2.0) * (uy * single(pi)))) * sqrt(((single(2.0) * ux) - (ux * ux))); end
\begin{array}{l}
\\
\sin \left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{2 \cdot ux - ux \cdot ux}
\end{array}
Initial program 56.8%
associate-*l*56.8%
sub-neg56.8%
+-commutative56.8%
distribute-rgt-neg-in56.8%
fma-def57.0%
+-commutative57.0%
associate-+r-57.0%
fma-def57.0%
neg-sub057.0%
+-commutative57.0%
associate-+r-56.9%
associate--r-56.9%
neg-sub056.9%
+-commutative56.9%
sub-neg56.9%
fma-def56.9%
Simplified56.9%
Taylor expanded in ux around 0 98.2%
Taylor expanded in maxCos around 0 93.9%
+-commutative93.9%
mul-1-neg93.9%
unsub-neg93.9%
unpow293.9%
Simplified93.9%
Final simplification93.9%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* uy (* PI (sqrt (- (* 2.0 ux) (* ux ux)))))))
float code(float ux, float uy, float maxCos) {
return 2.0f * (uy * (((float) M_PI) * sqrtf(((2.0f * ux) - (ux * ux)))));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(uy * Float32(Float32(pi) * sqrt(Float32(Float32(Float32(2.0) * ux) - Float32(ux * ux)))))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * (uy * (single(pi) * sqrt(((single(2.0) * ux) - (ux * ux))))); end
\begin{array}{l}
\\
2 \cdot \left(uy \cdot \left(\pi \cdot \sqrt{2 \cdot ux - ux \cdot ux}\right)\right)
\end{array}
Initial program 56.8%
associate-*l*56.8%
sub-neg56.8%
+-commutative56.8%
distribute-rgt-neg-in56.8%
fma-def57.0%
+-commutative57.0%
associate-+r-57.0%
fma-def57.0%
neg-sub057.0%
+-commutative57.0%
associate-+r-56.9%
associate--r-56.9%
neg-sub056.9%
+-commutative56.9%
sub-neg56.9%
fma-def56.9%
Simplified56.9%
Taylor expanded in ux around 0 98.2%
Taylor expanded in uy around 0 79.5%
Taylor expanded in maxCos around 0 76.8%
associate-*l*76.8%
+-commutative76.8%
mul-1-neg76.8%
unsub-neg76.8%
unpow276.8%
Simplified76.8%
Final simplification76.8%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* (* uy PI) (sqrt (* 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
return 2.0f * ((uy * ((float) M_PI)) * sqrtf((2.0f * ux)));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(Float32(uy * Float32(pi)) * sqrt(Float32(Float32(2.0) * ux)))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * ((uy * single(pi)) * sqrt((single(2.0) * ux))); end
\begin{array}{l}
\\
2 \cdot \left(\left(uy \cdot \pi\right) \cdot \sqrt{2 \cdot ux}\right)
\end{array}
Initial program 56.8%
associate-*l*56.8%
sub-neg56.8%
+-commutative56.8%
distribute-rgt-neg-in56.8%
fma-def57.0%
+-commutative57.0%
associate-+r-57.0%
fma-def57.0%
neg-sub057.0%
+-commutative57.0%
associate-+r-56.9%
associate--r-56.9%
neg-sub056.9%
+-commutative56.9%
sub-neg56.9%
fma-def56.9%
Simplified56.9%
Taylor expanded in uy around 0 50.2%
Taylor expanded in ux around 0 64.7%
sub-neg64.7%
sub-neg64.7%
neg-mul-164.7%
associate--l+64.7%
sub-neg64.7%
metadata-eval64.7%
associate--l+64.7%
distribute-neg-in64.7%
metadata-eval64.7%
+-commutative64.7%
sub-neg64.7%
associate-+r-64.7%
metadata-eval64.7%
Simplified64.7%
Taylor expanded in maxCos around 0 63.1%
Final simplification63.1%
(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 56.8%
associate-*l*56.8%
sub-neg56.8%
+-commutative56.8%
distribute-rgt-neg-in56.8%
fma-def57.0%
+-commutative57.0%
associate-+r-57.0%
fma-def57.0%
neg-sub057.0%
+-commutative57.0%
associate-+r-56.9%
associate--r-56.9%
neg-sub056.9%
+-commutative56.9%
sub-neg56.9%
fma-def56.9%
Simplified56.9%
Taylor expanded in ux around 0 98.2%
add-cube-cbrt97.0%
pow397.1%
Applied egg-rr97.1%
Taylor expanded in uy around 0 7.1%
Final simplification7.1%
herbie shell --seed 2023240
(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)))))))