
(FPCore (ux uy maxCos) :precision binary32 (let* ((t_0 (+ (- 1.0 ux) (* ux maxCos)))) (* (cos (* (* 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 cosf(((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(cos(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 = cos(((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\\
\cos \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)))) (* (cos (* (* 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 cosf(((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(cos(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 = cos(((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\\
\cos \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
(*
(cos (* (* uy 2.0) PI))
(sqrt
(-
(* maxCos (- (* (- maxCos) (pow ux 2.0)) (* ux (+ 2.0 (* ux -2.0)))))
(* ux (+ ux -2.0))))))
float code(float ux, float uy, float maxCos) {
return cosf(((uy * 2.0f) * ((float) M_PI))) * sqrtf(((maxCos * ((-maxCos * powf(ux, 2.0f)) - (ux * (2.0f + (ux * -2.0f))))) - (ux * (ux + -2.0f))));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(Float32(maxCos * Float32(Float32(Float32(-maxCos) * (ux ^ Float32(2.0))) - Float32(ux * Float32(Float32(2.0) + Float32(ux * Float32(-2.0)))))) - Float32(ux * Float32(ux + Float32(-2.0)))))) end
function tmp = code(ux, uy, maxCos) tmp = cos(((uy * single(2.0)) * single(pi))) * sqrt(((maxCos * ((-maxCos * (ux ^ single(2.0))) - (ux * (single(2.0) + (ux * single(-2.0)))))) - (ux * (ux + single(-2.0))))); end
\begin{array}{l}
\\
\cos \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{maxCos \cdot \left(\left(-maxCos\right) \cdot {ux}^{2} - ux \cdot \left(2 + ux \cdot -2\right)\right) - ux \cdot \left(ux + -2\right)}
\end{array}
Initial program 54.5%
Taylor expanded in ux around 0 57.5%
Taylor expanded in maxCos around 0 99.0%
associate-*r*99.0%
mul-1-neg99.0%
*-commutative99.0%
sub-neg99.0%
metadata-eval99.0%
Simplified99.0%
(FPCore (ux uy maxCos)
:precision binary32
(let* ((t_0 (cos (* (* uy 2.0) PI))))
(if (<= t_0 0.9997900128364563)
(* t_0 (sqrt (* ux (- 2.0 ux))))
(sqrt
(*
ux
(+
2.0
(+ (* maxCos -2.0) (* ux (+ -1.0 (* maxCos (- 2.0 maxCos)))))))))))
float code(float ux, float uy, float maxCos) {
float t_0 = cosf(((uy * 2.0f) * ((float) M_PI)));
float tmp;
if (t_0 <= 0.9997900128364563f) {
tmp = t_0 * sqrtf((ux * (2.0f - ux)));
} else {
tmp = sqrtf((ux * (2.0f + ((maxCos * -2.0f) + (ux * (-1.0f + (maxCos * (2.0f - maxCos))))))));
}
return tmp;
}
function code(ux, uy, maxCos) t_0 = cos(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) tmp = Float32(0.0) if (t_0 <= Float32(0.9997900128364563)) tmp = Float32(t_0 * sqrt(Float32(ux * Float32(Float32(2.0) - ux)))); else tmp = sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(maxCos * Float32(-2.0)) + Float32(ux * Float32(Float32(-1.0) + Float32(maxCos * Float32(Float32(2.0) - maxCos)))))))); end return tmp end
function tmp_2 = code(ux, uy, maxCos) t_0 = cos(((uy * single(2.0)) * single(pi))); tmp = single(0.0); if (t_0 <= single(0.9997900128364563)) tmp = t_0 * sqrt((ux * (single(2.0) - ux))); else tmp = sqrt((ux * (single(2.0) + ((maxCos * single(-2.0)) + (ux * (single(-1.0) + (maxCos * (single(2.0) - maxCos)))))))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \cos \left(\left(uy \cdot 2\right) \cdot \pi\right)\\
\mathbf{if}\;t\_0 \leq 0.9997900128364563:\\
\;\;\;\;t\_0 \cdot \sqrt{ux \cdot \left(2 - ux\right)}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{ux \cdot \left(2 + \left(maxCos \cdot -2 + ux \cdot \left(-1 + maxCos \cdot \left(2 - maxCos\right)\right)\right)\right)}\\
\end{array}
\end{array}
if (cos.f32 (*.f32 (*.f32 uy #s(literal 2 binary32)) (PI.f32))) < 0.999790013Initial program 52.5%
Taylor expanded in ux around 0 98.0%
Taylor expanded in maxCos around 0 92.4%
neg-mul-192.4%
unsub-neg92.4%
Simplified92.4%
if 0.999790013 < (cos.f32 (*.f32 (*.f32 uy #s(literal 2 binary32)) (PI.f32))) Initial program 55.3%
associate-*l*55.3%
sub-neg55.3%
+-commutative55.3%
distribute-rgt-neg-in55.3%
fma-define55.1%
Simplified55.6%
Taylor expanded in uy around 0 54.9%
Simplified54.5%
Taylor expanded in ux around inf 94.8%
Taylor expanded in maxCos around 0 94.8%
associate--l+94.8%
associate-*r/94.8%
metadata-eval94.8%
mul-1-neg94.8%
associate-*r/94.8%
metadata-eval94.8%
Simplified94.8%
Taylor expanded in ux around 0 94.9%
Final simplification94.2%
(FPCore (ux uy maxCos) :precision binary32 (* (cos (* (* uy 2.0) PI)) (sqrt (* ux (- (- 2.0 (* ux (pow (+ maxCos -1.0) 2.0))) (* 2.0 maxCos))))))
float code(float ux, float uy, float maxCos) {
return cosf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((ux * ((2.0f - (ux * powf((maxCos + -1.0f), 2.0f))) - (2.0f * maxCos))));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(ux * Float32(Float32(Float32(2.0) - Float32(ux * (Float32(maxCos + Float32(-1.0)) ^ Float32(2.0)))) - Float32(Float32(2.0) * maxCos))))) end
function tmp = code(ux, uy, maxCos) tmp = cos(((uy * single(2.0)) * single(pi))) * sqrt((ux * ((single(2.0) - (ux * ((maxCos + single(-1.0)) ^ single(2.0)))) - (single(2.0) * maxCos)))); end
\begin{array}{l}
\\
\cos \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{ux \cdot \left(\left(2 - ux \cdot {\left(maxCos + -1\right)}^{2}\right) - 2 \cdot maxCos\right)}
\end{array}
Initial program 54.5%
Taylor expanded in ux around 0 99.0%
Final simplification99.0%
(FPCore (ux uy maxCos) :precision binary32 (* (cos (* (* uy 2.0) PI)) (sqrt (- (* (- maxCos) (* ux (+ 2.0 (* ux -2.0)))) (* ux (+ ux -2.0))))))
float code(float ux, float uy, float maxCos) {
return cosf(((uy * 2.0f) * ((float) M_PI))) * sqrtf(((-maxCos * (ux * (2.0f + (ux * -2.0f)))) - (ux * (ux + -2.0f))));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(Float32(Float32(-maxCos) * Float32(ux * Float32(Float32(2.0) + Float32(ux * Float32(-2.0))))) - Float32(ux * Float32(ux + Float32(-2.0)))))) end
function tmp = code(ux, uy, maxCos) tmp = cos(((uy * single(2.0)) * single(pi))) * sqrt(((-maxCos * (ux * (single(2.0) + (ux * single(-2.0))))) - (ux * (ux + single(-2.0))))); end
\begin{array}{l}
\\
\cos \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{\left(-maxCos\right) \cdot \left(ux \cdot \left(2 + ux \cdot -2\right)\right) - ux \cdot \left(ux + -2\right)}
\end{array}
Initial program 54.5%
Taylor expanded in ux around 0 57.5%
Taylor expanded in maxCos around 0 98.0%
associate-*r*98.0%
mul-1-neg98.0%
*-commutative98.0%
sub-neg98.0%
metadata-eval98.0%
Simplified98.0%
(FPCore (ux uy maxCos)
:precision binary32
(if (<= uy 0.0010000000474974513)
(sqrt
(*
ux
(+ 2.0 (+ (* maxCos -2.0) (* ux (+ -1.0 (* maxCos (- 2.0 maxCos))))))))
(* (cos (* uy (* 2.0 PI))) (sqrt (* 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
float tmp;
if (uy <= 0.0010000000474974513f) {
tmp = sqrtf((ux * (2.0f + ((maxCos * -2.0f) + (ux * (-1.0f + (maxCos * (2.0f - maxCos))))))));
} else {
tmp = cosf((uy * (2.0f * ((float) M_PI)))) * sqrtf((2.0f * ux));
}
return tmp;
}
function code(ux, uy, maxCos) tmp = Float32(0.0) if (uy <= Float32(0.0010000000474974513)) tmp = sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(maxCos * Float32(-2.0)) + Float32(ux * Float32(Float32(-1.0) + Float32(maxCos * Float32(Float32(2.0) - maxCos)))))))); else tmp = Float32(cos(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(0.0010000000474974513)) tmp = sqrt((ux * (single(2.0) + ((maxCos * single(-2.0)) + (ux * (single(-1.0) + (maxCos * (single(2.0) - maxCos)))))))); else tmp = cos((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 \leq 0.0010000000474974513:\\
\;\;\;\;\sqrt{ux \cdot \left(2 + \left(maxCos \cdot -2 + ux \cdot \left(-1 + maxCos \cdot \left(2 - maxCos\right)\right)\right)\right)}\\
\mathbf{else}:\\
\;\;\;\;\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{2 \cdot ux}\\
\end{array}
\end{array}
if uy < 0.00100000005Initial program 55.4%
associate-*l*55.4%
sub-neg55.4%
+-commutative55.4%
distribute-rgt-neg-in55.4%
fma-define55.2%
Simplified55.6%
Taylor expanded in uy around 0 55.3%
Simplified54.9%
Taylor expanded in ux around inf 97.0%
Taylor expanded in maxCos around 0 97.0%
associate--l+97.0%
associate-*r/97.0%
metadata-eval97.0%
mul-1-neg97.0%
associate-*r/97.0%
metadata-eval97.0%
Simplified97.0%
Taylor expanded in ux around 0 97.1%
if 0.00100000005 < uy Initial program 52.8%
associate-*l*52.8%
sub-neg52.8%
+-commutative52.8%
distribute-rgt-neg-in52.8%
fma-define53.1%
Simplified53.2%
Taylor expanded in maxCos around 0 50.0%
Taylor expanded in ux around 0 75.7%
Final simplification89.5%
(FPCore (ux uy maxCos) :precision binary32 (sqrt (* ux (+ 2.0 (+ (* maxCos -2.0) (* ux (+ -1.0 (* maxCos (- 2.0 maxCos)))))))))
float code(float ux, float uy, float maxCos) {
return sqrtf((ux * (2.0f + ((maxCos * -2.0f) + (ux * (-1.0f + (maxCos * (2.0f - maxCos))))))));
}
real(4) function code(ux, uy, maxcos)
real(4), intent (in) :: ux
real(4), intent (in) :: uy
real(4), intent (in) :: maxcos
code = sqrt((ux * (2.0e0 + ((maxcos * (-2.0e0)) + (ux * ((-1.0e0) + (maxcos * (2.0e0 - maxcos))))))))
end function
function code(ux, uy, maxCos) return sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(maxCos * Float32(-2.0)) + Float32(ux * Float32(Float32(-1.0) + Float32(maxCos * Float32(Float32(2.0) - maxCos)))))))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((ux * (single(2.0) + ((maxCos * single(-2.0)) + (ux * (single(-1.0) + (maxCos * (single(2.0) - maxCos)))))))); end
\begin{array}{l}
\\
\sqrt{ux \cdot \left(2 + \left(maxCos \cdot -2 + ux \cdot \left(-1 + maxCos \cdot \left(2 - maxCos\right)\right)\right)\right)}
\end{array}
Initial program 54.5%
associate-*l*54.5%
sub-neg54.5%
+-commutative54.5%
distribute-rgt-neg-in54.5%
fma-define54.4%
Simplified54.8%
Taylor expanded in uy around 0 46.2%
Simplified46.0%
Taylor expanded in ux around inf 76.6%
Taylor expanded in maxCos around 0 76.6%
associate--l+76.6%
associate-*r/76.6%
metadata-eval76.6%
mul-1-neg76.6%
associate-*r/76.6%
metadata-eval76.6%
Simplified76.6%
Taylor expanded in ux around 0 76.8%
Final simplification76.8%
(FPCore (ux uy maxCos) :precision binary32 (sqrt (- (* 2.0 ux) (* ux ux))))
float code(float ux, float uy, float maxCos) {
return sqrtf(((2.0f * ux) - (ux * ux)));
}
real(4) function code(ux, uy, maxcos)
real(4), intent (in) :: ux
real(4), intent (in) :: uy
real(4), intent (in) :: maxcos
code = sqrt(((2.0e0 * ux) - (ux * ux)))
end function
function code(ux, uy, maxCos) return sqrt(Float32(Float32(Float32(2.0) * ux) - Float32(ux * ux))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt(((single(2.0) * ux) - (ux * ux))); end
\begin{array}{l}
\\
\sqrt{2 \cdot ux - ux \cdot ux}
\end{array}
Initial program 54.5%
associate-*l*54.5%
sub-neg54.5%
+-commutative54.5%
distribute-rgt-neg-in54.5%
fma-define54.4%
Simplified54.8%
Taylor expanded in uy around 0 46.2%
Simplified46.0%
Taylor expanded in ux around inf 76.6%
Taylor expanded in maxCos around 0 70.7%
sub-neg70.7%
associate-*r/70.7%
metadata-eval70.7%
metadata-eval70.7%
Simplified70.7%
Taylor expanded in ux around 0 70.8%
mul-1-neg70.8%
unsub-neg70.8%
Simplified70.8%
sub-neg70.8%
distribute-rgt-in70.9%
Applied egg-rr70.9%
Final simplification70.9%
(FPCore (ux uy maxCos) :precision binary32 (sqrt (* ux (- 2.0 ux))))
float code(float ux, float uy, float maxCos) {
return sqrtf((ux * (2.0f - ux)));
}
real(4) function code(ux, uy, maxcos)
real(4), intent (in) :: ux
real(4), intent (in) :: uy
real(4), intent (in) :: maxcos
code = sqrt((ux * (2.0e0 - ux)))
end function
function code(ux, uy, maxCos) return sqrt(Float32(ux * Float32(Float32(2.0) - ux))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((ux * (single(2.0) - ux))); end
\begin{array}{l}
\\
\sqrt{ux \cdot \left(2 - ux\right)}
\end{array}
Initial program 54.5%
associate-*l*54.5%
sub-neg54.5%
+-commutative54.5%
distribute-rgt-neg-in54.5%
fma-define54.4%
Simplified54.8%
Taylor expanded in uy around 0 46.2%
Simplified46.0%
Taylor expanded in ux around inf 76.6%
Taylor expanded in maxCos around 0 70.7%
sub-neg70.7%
associate-*r/70.7%
metadata-eval70.7%
metadata-eval70.7%
Simplified70.7%
Taylor expanded in ux around 0 70.8%
mul-1-neg70.8%
unsub-neg70.8%
Simplified70.8%
(FPCore (ux uy maxCos) :precision binary32 (sqrt (* 2.0 ux)))
float code(float ux, float uy, float maxCos) {
return sqrtf((2.0f * ux));
}
real(4) function code(ux, uy, maxcos)
real(4), intent (in) :: ux
real(4), intent (in) :: uy
real(4), intent (in) :: maxcos
code = sqrt((2.0e0 * ux))
end function
function code(ux, uy, maxCos) return sqrt(Float32(Float32(2.0) * ux)) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((single(2.0) * ux)); end
\begin{array}{l}
\\
\sqrt{2 \cdot ux}
\end{array}
Initial program 54.5%
associate-*l*54.5%
sub-neg54.5%
+-commutative54.5%
distribute-rgt-neg-in54.5%
fma-define54.4%
Simplified54.8%
Taylor expanded in uy around 0 46.2%
Simplified46.0%
Taylor expanded in ux around 0 63.5%
Taylor expanded in maxCos around 0 60.0%
(FPCore (ux uy maxCos) :precision binary32 1.0)
float code(float ux, float uy, float maxCos) {
return 1.0f;
}
real(4) function code(ux, uy, maxcos)
real(4), intent (in) :: ux
real(4), intent (in) :: uy
real(4), intent (in) :: maxcos
code = 1.0e0
end function
function code(ux, uy, maxCos) return Float32(1.0) end
function tmp = code(ux, uy, maxCos) tmp = single(1.0); end
\begin{array}{l}
\\
1
\end{array}
Initial program 54.5%
associate-*l*54.5%
sub-neg54.5%
+-commutative54.5%
distribute-rgt-neg-in54.5%
fma-define54.4%
Simplified54.8%
Taylor expanded in uy around 0 46.2%
Simplified46.0%
Taylor expanded in ux around -inf 19.1%
mul-1-neg19.1%
associate-*r*19.1%
distribute-rgt-neg-in19.1%
sub-neg19.1%
metadata-eval19.1%
distribute-neg-in19.1%
mul-1-neg19.1%
metadata-eval19.1%
+-commutative19.1%
associate-*r*19.1%
unpow219.1%
swap-sqr19.1%
+-commutative19.1%
fma-undefine19.1%
+-commutative19.1%
fma-undefine19.1%
unpow219.1%
fma-undefine19.1%
+-commutative19.1%
mul-1-neg19.1%
unsub-neg19.1%
Simplified19.1%
Taylor expanded in ux around 0 19.2%
herbie shell --seed 2024107
(FPCore (ux uy maxCos)
:name "UniformSampleCone, x"
: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)))
(* (cos (* (* uy 2.0) PI)) (sqrt (- 1.0 (* (+ (- 1.0 ux) (* ux maxCos)) (+ (- 1.0 ux) (* ux maxCos)))))))