
(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 9 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
(-
(* ux (* (- ux) (pow (+ -1.0 maxCos) 2.0)))
(* ux (fma maxCos 2.0 -2.0))))))
float code(float ux, float uy, float maxCos) {
return cosf((uy * (2.0f * ((float) M_PI)))) * sqrtf(((ux * (-ux * powf((-1.0f + maxCos), 2.0f))) - (ux * fmaf(maxCos, 2.0f, -2.0f))));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(Float32(ux * Float32(Float32(-ux) * (Float32(Float32(-1.0) + maxCos) ^ Float32(2.0)))) - Float32(ux * fma(maxCos, Float32(2.0), Float32(-2.0)))))) end
\begin{array}{l}
\\
\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(\left(-ux\right) \cdot {\left(-1 + maxCos\right)}^{2}\right) - ux \cdot \mathsf{fma}\left(maxCos, 2, -2\right)}
\end{array}
Initial program 58.0%
associate-*l*58.0%
sub-neg58.0%
+-commutative58.0%
distribute-rgt-neg-in58.0%
fma-define58.1%
Simplified58.4%
Taylor expanded in ux around 0 99.0%
distribute-rgt-in99.1%
associate-*r*99.1%
neg-mul-199.1%
sub-neg99.1%
metadata-eval99.1%
+-commutative99.1%
mul-1-neg99.1%
*-commutative99.1%
fma-neg99.1%
metadata-eval99.1%
Applied egg-rr99.1%
Final simplification99.1%
(FPCore (ux uy maxCos) :precision binary32 (* (cos (* uy (* 2.0 PI))) (sqrt (* ux (- (- 2.0 (* 2.0 maxCos)) (* ux (pow (+ -1.0 maxCos) 2.0)))))))
float code(float ux, float uy, float maxCos) {
return cosf((uy * (2.0f * ((float) M_PI)))) * sqrtf((ux * ((2.0f - (2.0f * maxCos)) - (ux * powf((-1.0f + maxCos), 2.0f)))));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(ux * Float32(Float32(Float32(2.0) - Float32(Float32(2.0) * maxCos)) - Float32(ux * (Float32(Float32(-1.0) + maxCos) ^ Float32(2.0))))))) end
function tmp = code(ux, uy, maxCos) tmp = cos((uy * (single(2.0) * single(pi)))) * sqrt((ux * ((single(2.0) - (single(2.0) * maxCos)) - (ux * ((single(-1.0) + maxCos) ^ single(2.0)))))); end
\begin{array}{l}
\\
\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(\left(2 - 2 \cdot maxCos\right) - ux \cdot {\left(-1 + maxCos\right)}^{2}\right)}
\end{array}
Initial program 58.0%
associate-*l*58.0%
sub-neg58.0%
+-commutative58.0%
distribute-rgt-neg-in58.0%
fma-define58.1%
Simplified58.4%
Taylor expanded in ux around 0 99.0%
Final simplification99.0%
(FPCore (ux uy maxCos) :precision binary32 (* (cos (* PI (* uy 2.0))) (sqrt (* ux (+ (- 2.0 (* ux (pow (+ -1.0 maxCos) 2.0))) (* maxCos -2.0))))))
float code(float ux, float uy, float maxCos) {
return cosf((((float) M_PI) * (uy * 2.0f))) * sqrtf((ux * ((2.0f - (ux * powf((-1.0f + maxCos), 2.0f))) + (maxCos * -2.0f))));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(Float32(pi) * Float32(uy * Float32(2.0)))) * sqrt(Float32(ux * Float32(Float32(Float32(2.0) - Float32(ux * (Float32(Float32(-1.0) + maxCos) ^ Float32(2.0)))) + Float32(maxCos * Float32(-2.0)))))) end
function tmp = code(ux, uy, maxCos) tmp = cos((single(pi) * (uy * single(2.0)))) * sqrt((ux * ((single(2.0) - (ux * ((single(-1.0) + maxCos) ^ single(2.0)))) + (maxCos * single(-2.0))))); end
\begin{array}{l}
\\
\cos \left(\pi \cdot \left(uy \cdot 2\right)\right) \cdot \sqrt{ux \cdot \left(\left(2 - ux \cdot {\left(-1 + maxCos\right)}^{2}\right) + maxCos \cdot -2\right)}
\end{array}
Initial program 58.0%
Taylor expanded in ux around 0 99.0%
cancel-sign-sub-inv99.0%
associate-*r*99.0%
mul-1-neg99.0%
sub-neg99.0%
metadata-eval99.0%
+-commutative99.0%
metadata-eval99.0%
*-commutative99.0%
Simplified99.0%
Final simplification99.0%
(FPCore (ux uy maxCos) :precision binary32 (* (cos (* uy (* 2.0 PI))) (sqrt (+ (* maxCos (* ux (- (* 2.0 ux) 2.0))) (* ux (- 2.0 ux))))))
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 * (2.0f - ux))));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(Float32(maxCos * Float32(ux * Float32(Float32(Float32(2.0) * ux) - Float32(2.0)))) + Float32(ux * Float32(Float32(2.0) - ux))))) 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 * (single(2.0) - ux)))); end
\begin{array}{l}
\\
\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{maxCos \cdot \left(ux \cdot \left(2 \cdot ux - 2\right)\right) + ux \cdot \left(2 - ux\right)}
\end{array}
Initial program 58.0%
associate-*l*58.0%
sub-neg58.0%
+-commutative58.0%
distribute-rgt-neg-in58.0%
fma-define58.1%
Simplified58.4%
Taylor expanded in ux around 0 99.0%
Taylor expanded in maxCos around 0 98.4%
Final simplification98.4%
(FPCore (ux uy maxCos) :precision binary32 (* (cos (* uy (* 2.0 PI))) (sqrt (* ux (+ 2.0 (+ (* maxCos -2.0) (* ux (+ -1.0 (* 2.0 maxCos)))))))))
float code(float ux, float uy, float maxCos) {
return cosf((uy * (2.0f * ((float) M_PI)))) * sqrtf((ux * (2.0f + ((maxCos * -2.0f) + (ux * (-1.0f + (2.0f * maxCos)))))));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(maxCos * Float32(-2.0)) + Float32(ux * Float32(Float32(-1.0) + 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) + ((maxCos * single(-2.0)) + (ux * (single(-1.0) + (single(2.0) * maxCos))))))); end
\begin{array}{l}
\\
\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(2 + \left(maxCos \cdot -2 + ux \cdot \left(-1 + 2 \cdot maxCos\right)\right)\right)}
\end{array}
Initial program 58.0%
associate-*l*58.0%
sub-neg58.0%
+-commutative58.0%
distribute-rgt-neg-in58.0%
fma-define58.1%
Simplified58.4%
Taylor expanded in maxCos around 0 57.6%
Taylor expanded in ux around 0 98.4%
Final simplification98.4%
(FPCore (ux uy maxCos) :precision binary32 (if (<= uy 0.0007999999797903001) (sqrt (* ux (- 2.0 ux))) (* (cos (* uy (* 2.0 PI))) (sqrt (* 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
float tmp;
if (uy <= 0.0007999999797903001f) {
tmp = sqrtf((ux * (2.0f - ux)));
} 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(0.0007999999797903001)) tmp = sqrt(Float32(ux * Float32(Float32(2.0) - ux))); 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(0.0007999999797903001)) tmp = sqrt((ux * (single(2.0) - ux))); 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 0.0007999999797903001:\\
\;\;\;\;\sqrt{ux \cdot \left(2 - ux\right)}\\
\mathbf{else}:\\
\;\;\;\;\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{2 \cdot ux}\\
\end{array}
\end{array}
if uy < 7.9999998e-4Initial program 59.9%
associate-*l*59.9%
sub-neg59.9%
+-commutative59.9%
distribute-rgt-neg-in59.9%
fma-define60.2%
Simplified60.5%
Taylor expanded in ux around 0 99.3%
distribute-rgt-in99.5%
associate-*r*99.5%
neg-mul-199.5%
sub-neg99.5%
metadata-eval99.5%
+-commutative99.5%
mul-1-neg99.5%
*-commutative99.5%
fma-neg99.5%
metadata-eval99.5%
Applied egg-rr99.5%
Taylor expanded in maxCos around 0 94.9%
associate-*r*94.9%
+-commutative94.9%
mul-1-neg94.9%
unpow294.9%
distribute-lft-neg-in94.9%
distribute-rgt-in94.8%
unsub-neg94.8%
Simplified94.8%
Taylor expanded in uy around 0 93.3%
if 7.9999998e-4 < uy Initial program 53.2%
associate-*l*53.2%
sub-neg53.2%
+-commutative53.2%
distribute-rgt-neg-in53.2%
fma-define53.1%
Simplified53.2%
Taylor expanded in maxCos around 0 51.5%
Taylor expanded in ux around 0 74.1%
*-commutative74.1%
Simplified74.1%
Final simplification87.7%
(FPCore (ux uy maxCos) :precision binary32 (* (cos (* uy (* 2.0 PI))) (sqrt (* ux (- 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
return cosf((uy * (2.0f * ((float) M_PI)))) * sqrtf((ux * (2.0f - ux)));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(ux * Float32(Float32(2.0) - ux)))) end
function tmp = code(ux, uy, maxCos) tmp = cos((uy * (single(2.0) * single(pi)))) * sqrt((ux * (single(2.0) - ux))); end
\begin{array}{l}
\\
\cos \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(2 - ux\right)}
\end{array}
Initial program 58.0%
associate-*l*58.0%
sub-neg58.0%
+-commutative58.0%
distribute-rgt-neg-in58.0%
fma-define58.1%
Simplified58.4%
Taylor expanded in ux around 0 99.0%
Taylor expanded in maxCos around 0 94.1%
neg-mul-194.1%
unsub-neg94.1%
Simplified94.1%
(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 58.0%
associate-*l*58.0%
sub-neg58.0%
+-commutative58.0%
distribute-rgt-neg-in58.0%
fma-define58.1%
Simplified58.4%
Taylor expanded in ux around 0 99.0%
distribute-rgt-in99.1%
associate-*r*99.1%
neg-mul-199.1%
sub-neg99.1%
metadata-eval99.1%
+-commutative99.1%
mul-1-neg99.1%
*-commutative99.1%
fma-neg99.1%
metadata-eval99.1%
Applied egg-rr99.1%
Taylor expanded in maxCos around 0 94.1%
associate-*r*94.1%
+-commutative94.1%
mul-1-neg94.1%
unpow294.1%
distribute-lft-neg-in94.1%
distribute-rgt-in94.1%
unsub-neg94.1%
Simplified94.1%
Taylor expanded in uy around 0 78.3%
(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 58.0%
associate-*l*58.0%
sub-neg58.0%
+-commutative58.0%
distribute-rgt-neg-in58.0%
fma-define58.1%
Simplified58.4%
Taylor expanded in uy around 0 51.1%
Simplified51.2%
Taylor expanded in ux around 0 63.9%
Taylor expanded in maxCos around 0 62.3%
herbie shell --seed 2024108
(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)))))))