
(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 (* (sin (* (* uy 2.0) PI)) (sqrt (* ux (- 2.0 (+ ux (* maxCos (+ 2.0 (* ux (+ maxCos -2.0))))))))))
float code(float ux, float uy, float maxCos) {
return sinf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((ux * (2.0f - (ux + (maxCos * (2.0f + (ux * (maxCos + -2.0f))))))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(ux * Float32(Float32(2.0) - Float32(ux + Float32(maxCos * Float32(Float32(2.0) + Float32(ux * Float32(maxCos + Float32(-2.0)))))))))) end
function tmp = code(ux, uy, maxCos) tmp = sin(((uy * single(2.0)) * single(pi))) * sqrt((ux * (single(2.0) - (ux + (maxCos * (single(2.0) + (ux * (maxCos + single(-2.0))))))))); end
\begin{array}{l}
\\
\sin \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{ux \cdot \left(2 - \left(ux + maxCos \cdot \left(2 + ux \cdot \left(maxCos + -2\right)\right)\right)\right)}
\end{array}
Initial program 56.6%
Taylor expanded in ux around 0 98.3%
associate--l+98.3%
associate-*r*98.3%
mul-1-neg98.3%
sub-neg98.3%
metadata-eval98.3%
+-commutative98.3%
Simplified98.3%
Taylor expanded in maxCos around 0 98.3%
Taylor expanded in ux around -inf 98.3%
associate-*r*98.3%
neg-mul-198.3%
sub-neg98.3%
metadata-eval98.3%
Simplified98.3%
Final simplification98.3%
(FPCore (ux uy maxCos) :precision binary32 (* (sqrt (* ux (- 2.0 (+ ux (* maxCos (+ 2.0 (* ux -2.0))))))) (sin (* 2.0 (* uy PI)))))
float code(float ux, float uy, float maxCos) {
return sqrtf((ux * (2.0f - (ux + (maxCos * (2.0f + (ux * -2.0f))))))) * sinf((2.0f * (uy * ((float) M_PI))));
}
function code(ux, uy, maxCos) return Float32(sqrt(Float32(ux * Float32(Float32(2.0) - Float32(ux + Float32(maxCos * Float32(Float32(2.0) + Float32(ux * Float32(-2.0)))))))) * sin(Float32(Float32(2.0) * Float32(uy * Float32(pi))))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((ux * (single(2.0) - (ux + (maxCos * (single(2.0) + (ux * single(-2.0)))))))) * sin((single(2.0) * (uy * single(pi)))); end
\begin{array}{l}
\\
\sqrt{ux \cdot \left(2 - \left(ux + maxCos \cdot \left(2 + ux \cdot -2\right)\right)\right)} \cdot \sin \left(2 \cdot \left(uy \cdot \pi\right)\right)
\end{array}
Initial program 56.6%
Taylor expanded in ux around 0 98.3%
associate--l+98.3%
associate-*r*98.3%
mul-1-neg98.3%
sub-neg98.3%
metadata-eval98.3%
+-commutative98.3%
Simplified98.3%
Taylor expanded in maxCos around -inf 50.1%
Taylor expanded in maxCos around 0 97.2%
fma-define97.2%
mul-1-neg97.2%
fmm-undef97.2%
neg-mul-197.2%
*-commutative97.2%
Simplified97.2%
Taylor expanded in uy around inf 97.2%
Final simplification97.2%
(FPCore (ux uy maxCos)
:precision binary32
(if (<= (* uy 2.0) 0.0006500000017695129)
(*
(sqrt (* ux (- 2.0 (+ ux (* maxCos (+ 2.0 (* ux (+ maxCos -2.0))))))))
(* (* uy 2.0) PI))
(* (sin (* 2.0 (* uy PI))) (sqrt (* ux (- 2.0 ux))))))
float code(float ux, float uy, float maxCos) {
float tmp;
if ((uy * 2.0f) <= 0.0006500000017695129f) {
tmp = sqrtf((ux * (2.0f - (ux + (maxCos * (2.0f + (ux * (maxCos + -2.0f)))))))) * ((uy * 2.0f) * ((float) M_PI));
} else {
tmp = sinf((2.0f * (uy * ((float) M_PI)))) * sqrtf((ux * (2.0f - ux)));
}
return tmp;
}
function code(ux, uy, maxCos) tmp = Float32(0.0) if (Float32(uy * Float32(2.0)) <= Float32(0.0006500000017695129)) tmp = Float32(sqrt(Float32(ux * Float32(Float32(2.0) - Float32(ux + Float32(maxCos * Float32(Float32(2.0) + Float32(ux * Float32(maxCos + Float32(-2.0))))))))) * Float32(Float32(uy * Float32(2.0)) * Float32(pi))); else tmp = Float32(sin(Float32(Float32(2.0) * Float32(uy * Float32(pi)))) * sqrt(Float32(ux * 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(0.0006500000017695129)) tmp = sqrt((ux * (single(2.0) - (ux + (maxCos * (single(2.0) + (ux * (maxCos + single(-2.0))))))))) * ((uy * single(2.0)) * single(pi)); else tmp = sin((single(2.0) * (uy * single(pi)))) * sqrt((ux * (single(2.0) - ux))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;uy \cdot 2 \leq 0.0006500000017695129:\\
\;\;\;\;\sqrt{ux \cdot \left(2 - \left(ux + maxCos \cdot \left(2 + ux \cdot \left(maxCos + -2\right)\right)\right)\right)} \cdot \left(\left(uy \cdot 2\right) \cdot \pi\right)\\
\mathbf{else}:\\
\;\;\;\;\sin \left(2 \cdot \left(uy \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(2 - ux\right)}\\
\end{array}
\end{array}
if (*.f32 uy #s(literal 2 binary32)) < 6.50000002e-4Initial program 58.2%
Taylor expanded in ux around 0 98.5%
associate--l+98.5%
associate-*r*98.5%
mul-1-neg98.5%
sub-neg98.5%
metadata-eval98.5%
+-commutative98.5%
Simplified98.5%
Taylor expanded in maxCos around 0 98.5%
Taylor expanded in ux around -inf 98.5%
associate-*r*98.5%
neg-mul-198.5%
sub-neg98.5%
metadata-eval98.5%
Simplified98.5%
Taylor expanded in uy around 0 97.9%
associate-*r*97.9%
*-commutative97.9%
Simplified97.9%
if 6.50000002e-4 < (*.f32 uy #s(literal 2 binary32)) Initial program 53.6%
Taylor expanded in ux around 0 97.9%
associate--l+97.9%
associate-*r*97.9%
mul-1-neg97.9%
sub-neg97.9%
metadata-eval97.9%
+-commutative97.9%
Simplified97.9%
Taylor expanded in maxCos around -inf 51.4%
Taylor expanded in maxCos around 0 97.2%
fma-define97.2%
mul-1-neg97.2%
fmm-undef97.2%
neg-mul-197.2%
*-commutative97.2%
Simplified97.2%
Taylor expanded in maxCos around 0 93.3%
Final simplification96.3%
(FPCore (ux uy maxCos) :precision binary32 (* (sqrt (* ux (- 2.0 (+ ux (* maxCos (+ 2.0 (* ux (+ maxCos -2.0)))))))) (* (* uy 2.0) PI)))
float code(float ux, float uy, float maxCos) {
return sqrtf((ux * (2.0f - (ux + (maxCos * (2.0f + (ux * (maxCos + -2.0f)))))))) * ((uy * 2.0f) * ((float) M_PI));
}
function code(ux, uy, maxCos) return Float32(sqrt(Float32(ux * Float32(Float32(2.0) - Float32(ux + Float32(maxCos * Float32(Float32(2.0) + Float32(ux * Float32(maxCos + Float32(-2.0))))))))) * Float32(Float32(uy * Float32(2.0)) * Float32(pi))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((ux * (single(2.0) - (ux + (maxCos * (single(2.0) + (ux * (maxCos + single(-2.0))))))))) * ((uy * single(2.0)) * single(pi)); end
\begin{array}{l}
\\
\sqrt{ux \cdot \left(2 - \left(ux + maxCos \cdot \left(2 + ux \cdot \left(maxCos + -2\right)\right)\right)\right)} \cdot \left(\left(uy \cdot 2\right) \cdot \pi\right)
\end{array}
Initial program 56.6%
Taylor expanded in ux around 0 98.3%
associate--l+98.3%
associate-*r*98.3%
mul-1-neg98.3%
sub-neg98.3%
metadata-eval98.3%
+-commutative98.3%
Simplified98.3%
Taylor expanded in maxCos around 0 98.3%
Taylor expanded in ux around -inf 98.3%
associate-*r*98.3%
neg-mul-198.3%
sub-neg98.3%
metadata-eval98.3%
Simplified98.3%
Taylor expanded in uy around 0 81.7%
associate-*r*81.7%
*-commutative81.7%
Simplified81.7%
Final simplification81.7%
(FPCore (ux uy maxCos) :precision binary32 (if (<= ux 0.00018000000272877514) (* 2.0 (* (* uy PI) (sqrt (* ux (- 2.0 (* 2.0 maxCos)))))) (* 2.0 (* (* uy PI) (sqrt (+ 1.0 (* (- 1.0 ux) (+ ux -1.0))))))))
float code(float ux, float uy, float maxCos) {
float tmp;
if (ux <= 0.00018000000272877514f) {
tmp = 2.0f * ((uy * ((float) M_PI)) * sqrtf((ux * (2.0f - (2.0f * maxCos)))));
} else {
tmp = 2.0f * ((uy * ((float) M_PI)) * sqrtf((1.0f + ((1.0f - ux) * (ux + -1.0f)))));
}
return tmp;
}
function code(ux, uy, maxCos) tmp = Float32(0.0) if (ux <= Float32(0.00018000000272877514)) tmp = Float32(Float32(2.0) * Float32(Float32(uy * Float32(pi)) * sqrt(Float32(ux * Float32(Float32(2.0) - Float32(Float32(2.0) * maxCos)))))); else tmp = Float32(Float32(2.0) * Float32(Float32(uy * Float32(pi)) * sqrt(Float32(Float32(1.0) + Float32(Float32(Float32(1.0) - ux) * Float32(ux + Float32(-1.0))))))); end return tmp end
function tmp_2 = code(ux, uy, maxCos) tmp = single(0.0); if (ux <= single(0.00018000000272877514)) tmp = single(2.0) * ((uy * single(pi)) * sqrt((ux * (single(2.0) - (single(2.0) * maxCos))))); else tmp = single(2.0) * ((uy * single(pi)) * sqrt((single(1.0) + ((single(1.0) - ux) * (ux + single(-1.0)))))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;ux \leq 0.00018000000272877514:\\
\;\;\;\;2 \cdot \left(\left(uy \cdot \pi\right) \cdot \sqrt{ux \cdot \left(2 - 2 \cdot maxCos\right)}\right)\\
\mathbf{else}:\\
\;\;\;\;2 \cdot \left(\left(uy \cdot \pi\right) \cdot \sqrt{1 + \left(1 - ux\right) \cdot \left(ux + -1\right)}\right)\\
\end{array}
\end{array}
if ux < 1.80000003e-4Initial program 34.2%
associate-*l*34.2%
sub-neg34.2%
+-commutative34.2%
distribute-rgt-neg-in34.2%
fma-define34.3%
Simplified34.3%
Taylor expanded in uy around 0 32.1%
Simplified32.1%
Taylor expanded in ux around 0 76.3%
if 1.80000003e-4 < ux Initial program 91.0%
associate-*l*91.0%
sub-neg91.0%
+-commutative91.0%
distribute-rgt-neg-in91.0%
fma-define91.3%
Simplified91.4%
Taylor expanded in uy around 0 78.4%
Simplified78.5%
Taylor expanded in maxCos around 0 72.6%
Final simplification74.8%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* (sqrt (* ux (- 2.0 (+ ux (* maxCos (+ 2.0 (* ux -2.0))))))) (* uy PI))))
float code(float ux, float uy, float maxCos) {
return 2.0f * (sqrtf((ux * (2.0f - (ux + (maxCos * (2.0f + (ux * -2.0f))))))) * (uy * ((float) M_PI)));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(sqrt(Float32(ux * Float32(Float32(2.0) - Float32(ux + Float32(maxCos * Float32(Float32(2.0) + Float32(ux * Float32(-2.0)))))))) * Float32(uy * Float32(pi)))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * (sqrt((ux * (single(2.0) - (ux + (maxCos * (single(2.0) + (ux * single(-2.0)))))))) * (uy * single(pi))); end
\begin{array}{l}
\\
2 \cdot \left(\sqrt{ux \cdot \left(2 - \left(ux + maxCos \cdot \left(2 + ux \cdot -2\right)\right)\right)} \cdot \left(uy \cdot \pi\right)\right)
\end{array}
Initial program 56.6%
Taylor expanded in ux around 0 98.3%
associate--l+98.3%
associate-*r*98.3%
mul-1-neg98.3%
sub-neg98.3%
metadata-eval98.3%
+-commutative98.3%
Simplified98.3%
Taylor expanded in maxCos around -inf 50.1%
Taylor expanded in maxCos around 0 97.2%
fma-define97.2%
mul-1-neg97.2%
fmm-undef97.2%
neg-mul-197.2%
*-commutative97.2%
Simplified97.2%
Taylor expanded in uy around 0 80.8%
Final simplification80.8%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* (* uy PI) (sqrt (* ux (- 2.0 (* 2.0 maxCos)))))))
float code(float ux, float uy, float maxCos) {
return 2.0f * ((uy * ((float) M_PI)) * sqrtf((ux * (2.0f - (2.0f * maxCos)))));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(Float32(uy * Float32(pi)) * sqrt(Float32(ux * Float32(Float32(2.0) - Float32(Float32(2.0) * maxCos)))))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * ((uy * single(pi)) * sqrt((ux * (single(2.0) - (single(2.0) * maxCos))))); end
\begin{array}{l}
\\
2 \cdot \left(\left(uy \cdot \pi\right) \cdot \sqrt{ux \cdot \left(2 - 2 \cdot maxCos\right)}\right)
\end{array}
Initial program 56.6%
associate-*l*56.6%
sub-neg56.6%
+-commutative56.6%
distribute-rgt-neg-in56.6%
fma-define56.8%
Simplified56.8%
Taylor expanded in uy around 0 50.4%
Simplified50.4%
Taylor expanded in ux around 0 65.0%
Final simplification65.0%
(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 56.6%
associate-*l*56.6%
sub-neg56.6%
+-commutative56.6%
distribute-rgt-neg-in56.6%
fma-define56.8%
Simplified56.8%
Taylor expanded in uy around 0 50.4%
Simplified50.4%
Taylor expanded in ux around 0 7.1%
Taylor expanded in uy around 0 7.1%
herbie shell --seed 2024181
(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)))))))