
(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 12 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 (* (log1p (expm1 (sin (* 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 log1pf(expm1f(sinf((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(log1p(expm1(sin(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
\begin{array}{l}
\\
\mathsf{log1p}\left(\mathsf{expm1}\left(\sin \left(uy \cdot \left(2 \cdot \pi\right)\right)\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 61.0%
associate-*l*61.0%
sub-neg61.0%
+-commutative61.0%
distribute-rgt-neg-in61.0%
fma-define61.0%
Simplified61.1%
Taylor expanded in ux around 0 98.4%
log1p-expm1-u98.4%
Applied egg-rr98.4%
Final simplification98.4%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* 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 sinf((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(sin(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 = sin((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}
\\
\sin \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 61.0%
associate-*l*61.0%
sub-neg61.0%
+-commutative61.0%
distribute-rgt-neg-in61.0%
fma-define61.0%
Simplified61.1%
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 (+ (* 2.0 maxCos) (* ux (pow (+ -1.0 maxCos) 2.0))))))))
float code(float ux, float uy, float maxCos) {
return sinf((((float) M_PI) * (uy * 2.0f))) * sqrtf((ux * (2.0f - ((2.0f * maxCos) + (ux * powf((-1.0f + maxCos), 2.0f))))));
}
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(Float32(2.0) * maxCos) + Float32(ux * (Float32(Float32(-1.0) + maxCos) ^ Float32(2.0)))))))) end
function tmp = code(ux, uy, maxCos) tmp = sin((single(pi) * (uy * single(2.0)))) * sqrt((ux * (single(2.0) - ((single(2.0) * maxCos) + (ux * ((single(-1.0) + maxCos) ^ single(2.0))))))); end
\begin{array}{l}
\\
\sin \left(\pi \cdot \left(uy \cdot 2\right)\right) \cdot \sqrt{ux \cdot \left(2 - \left(2 \cdot maxCos + ux \cdot {\left(-1 + maxCos\right)}^{2}\right)\right)}
\end{array}
Initial program 61.0%
Taylor expanded in ux around 0 98.3%
associate--l+98.4%
associate-*r*98.4%
mul-1-neg98.4%
sub-neg98.4%
metadata-eval98.4%
+-commutative98.4%
Simplified98.4%
Final simplification98.4%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* uy (* 2.0 PI))) (sqrt (* ux (+ 2.0 (- (* maxCos (- (- (* 2.0 ux) (* ux maxCos)) 2.0)) ux))))))
float code(float ux, float uy, float maxCos) {
return sinf((uy * (2.0f * ((float) M_PI)))) * sqrtf((ux * (2.0f + ((maxCos * (((2.0f * ux) - (ux * maxCos)) - 2.0f)) - ux))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(maxCos * Float32(Float32(Float32(Float32(2.0) * ux) - Float32(ux * maxCos)) - Float32(2.0))) - ux))))) end
function tmp = code(ux, uy, maxCos) tmp = sin((uy * (single(2.0) * single(pi)))) * sqrt((ux * (single(2.0) + ((maxCos * (((single(2.0) * ux) - (ux * maxCos)) - single(2.0))) - ux)))); end
\begin{array}{l}
\\
\sin \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(2 + \left(maxCos \cdot \left(\left(2 \cdot ux - ux \cdot maxCos\right) - 2\right) - ux\right)\right)}
\end{array}
Initial program 61.0%
associate-*l*61.0%
sub-neg61.0%
+-commutative61.0%
distribute-rgt-neg-in61.0%
fma-define61.0%
Simplified61.1%
Taylor expanded in ux around 0 98.4%
Taylor expanded in maxCos around 0 98.3%
Final simplification98.3%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* uy (* 2.0 PI))) (sqrt (* ux (+ 2.0 (+ (+ -1.0 (- 1.0 ux)) (* maxCos (- (* 2.0 ux) 2.0))))))))
float code(float ux, float uy, float maxCos) {
return sinf((uy * (2.0f * ((float) M_PI)))) * sqrtf((ux * (2.0f + ((-1.0f + (1.0f - ux)) + (maxCos * ((2.0f * ux) - 2.0f))))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(Float32(-1.0) + Float32(Float32(1.0) - ux)) + Float32(maxCos * Float32(Float32(Float32(2.0) * ux) - Float32(2.0)))))))) end
function tmp = code(ux, uy, maxCos) tmp = sin((uy * (single(2.0) * single(pi)))) * sqrt((ux * (single(2.0) + ((single(-1.0) + (single(1.0) - ux)) + (maxCos * ((single(2.0) * ux) - single(2.0))))))); end
\begin{array}{l}
\\
\sin \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(2 + \left(\left(-1 + \left(1 - ux\right)\right) + maxCos \cdot \left(2 \cdot ux - 2\right)\right)\right)}
\end{array}
Initial program 61.0%
associate-*l*61.0%
sub-neg61.0%
+-commutative61.0%
distribute-rgt-neg-in61.0%
fma-define61.0%
Simplified61.1%
Taylor expanded in ux around 0 98.4%
Taylor expanded in maxCos around 0 97.9%
expm1-log1p-u97.9%
expm1-undefine97.9%
neg-mul-197.9%
Applied egg-rr97.9%
sub-neg97.9%
log1p-undefine97.9%
rem-exp-log97.9%
unsub-neg97.9%
metadata-eval97.9%
Simplified97.9%
Final simplification97.9%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* uy (* 2.0 PI))) (sqrt (* ux (+ 2.0 (- (* maxCos (- (* 2.0 ux) 2.0)) ux))))))
float code(float ux, float uy, float maxCos) {
return sinf((uy * (2.0f * ((float) M_PI)))) * sqrtf((ux * (2.0f + ((maxCos * ((2.0f * ux) - 2.0f)) - ux))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * 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((uy * (single(2.0) * single(pi)))) * sqrt((ux * (single(2.0) + ((maxCos * ((single(2.0) * ux) - single(2.0))) - ux)))); end
\begin{array}{l}
\\
\sin \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(2 + \left(maxCos \cdot \left(2 \cdot ux - 2\right) - ux\right)\right)}
\end{array}
Initial program 61.0%
associate-*l*61.0%
sub-neg61.0%
+-commutative61.0%
distribute-rgt-neg-in61.0%
fma-define61.0%
Simplified61.1%
Taylor expanded in ux around 0 98.4%
Taylor expanded in maxCos around 0 97.9%
neg-mul-197.9%
neg-sub097.9%
Applied egg-rr97.9%
neg-sub097.9%
Simplified97.9%
Final simplification97.9%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* uy (* 2.0 PI))) (sqrt (* ux (+ 2.0 (- (* maxCos -2.0) ux))))))
float code(float ux, float uy, float maxCos) {
return sinf((uy * (2.0f * ((float) M_PI)))) * sqrtf((ux * (2.0f + ((maxCos * -2.0f) - ux))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(maxCos * Float32(-2.0)) - ux))))) end
function tmp = code(ux, uy, maxCos) tmp = sin((uy * (single(2.0) * single(pi)))) * sqrt((ux * (single(2.0) + ((maxCos * single(-2.0)) - ux)))); end
\begin{array}{l}
\\
\sin \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(2 + \left(maxCos \cdot -2 - ux\right)\right)}
\end{array}
Initial program 61.0%
associate-*l*61.0%
sub-neg61.0%
+-commutative61.0%
distribute-rgt-neg-in61.0%
fma-define61.0%
Simplified61.1%
Taylor expanded in ux around 0 98.4%
Taylor expanded in maxCos around 0 97.9%
Taylor expanded in ux around 0 97.1%
Final simplification97.1%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* uy (* 2.0 PI))) (sqrt (* ux (- 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
return sinf((uy * (2.0f * ((float) M_PI)))) * sqrtf((ux * (2.0f - ux)));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(uy * Float32(Float32(2.0) * Float32(pi)))) * sqrt(Float32(ux * Float32(Float32(2.0) - ux)))) end
function tmp = code(ux, uy, maxCos) tmp = sin((uy * (single(2.0) * single(pi)))) * sqrt((ux * (single(2.0) - ux))); end
\begin{array}{l}
\\
\sin \left(uy \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{ux \cdot \left(2 - ux\right)}
\end{array}
Initial program 61.0%
associate-*l*61.0%
sub-neg61.0%
+-commutative61.0%
distribute-rgt-neg-in61.0%
fma-define61.0%
Simplified61.1%
Taylor expanded in ux around 0 98.4%
log1p-expm1-u98.4%
Applied egg-rr98.4%
Taylor expanded in maxCos around 0 93.0%
*-commutative93.0%
associate-*r*93.0%
*-commutative93.0%
associate-*l*93.0%
mul-1-neg93.0%
unsub-neg93.0%
Simplified93.0%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* (sqrt (+ (* maxCos (* ux (- (* 2.0 ux) 2.0))) (* ux (- 2.0 ux)))) (* uy PI))))
float code(float ux, float uy, float maxCos) {
return 2.0f * (sqrtf(((maxCos * (ux * ((2.0f * ux) - 2.0f))) + (ux * (2.0f - ux)))) * (uy * ((float) M_PI)));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(sqrt(Float32(Float32(maxCos * Float32(ux * Float32(Float32(Float32(2.0) * ux) - Float32(2.0)))) + Float32(ux * Float32(Float32(2.0) - ux)))) * Float32(uy * Float32(pi)))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * (sqrt(((maxCos * (ux * ((single(2.0) * ux) - single(2.0)))) + (ux * (single(2.0) - ux)))) * (uy * single(pi))); end
\begin{array}{l}
\\
2 \cdot \left(\sqrt{maxCos \cdot \left(ux \cdot \left(2 \cdot ux - 2\right)\right) + ux \cdot \left(2 - ux\right)} \cdot \left(uy \cdot \pi\right)\right)
\end{array}
Initial program 61.0%
associate-*l*61.0%
sub-neg61.0%
+-commutative61.0%
distribute-rgt-neg-in61.0%
fma-define61.0%
Simplified61.1%
Taylor expanded in ux around 0 98.4%
Taylor expanded in uy around 0 82.4%
Taylor expanded in maxCos around 0 82.1%
Final simplification82.1%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* (sqrt (* ux (+ 2.0 (- (* maxCos (- (* 2.0 ux) 2.0)) ux)))) (* uy PI))))
float code(float ux, float uy, float maxCos) {
return 2.0f * (sqrtf((ux * (2.0f + ((maxCos * ((2.0f * ux) - 2.0f)) - ux)))) * (uy * ((float) M_PI)));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(maxCos * Float32(Float32(Float32(2.0) * ux) - Float32(2.0))) - ux)))) * Float32(uy * Float32(pi)))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * (sqrt((ux * (single(2.0) + ((maxCos * ((single(2.0) * ux) - single(2.0))) - ux)))) * (uy * single(pi))); end
\begin{array}{l}
\\
2 \cdot \left(\sqrt{ux \cdot \left(2 + \left(maxCos \cdot \left(2 \cdot ux - 2\right) - ux\right)\right)} \cdot \left(uy \cdot \pi\right)\right)
\end{array}
Initial program 61.0%
associate-*l*61.0%
sub-neg61.0%
+-commutative61.0%
distribute-rgt-neg-in61.0%
fma-define61.0%
Simplified61.1%
Taylor expanded in ux around 0 98.4%
Taylor expanded in maxCos around 0 97.9%
Taylor expanded in uy around 0 82.1%
Final simplification82.1%
(FPCore (ux uy maxCos) :precision binary32 (* (* uy PI) (* 2.0 (sqrt (* ux (- 2.0 ux))))))
float code(float ux, float uy, float maxCos) {
return (uy * ((float) M_PI)) * (2.0f * sqrtf((ux * (2.0f - ux))));
}
function code(ux, uy, maxCos) return Float32(Float32(uy * Float32(pi)) * Float32(Float32(2.0) * sqrt(Float32(ux * Float32(Float32(2.0) - ux))))) end
function tmp = code(ux, uy, maxCos) tmp = (uy * single(pi)) * (single(2.0) * sqrt((ux * (single(2.0) - ux)))); end
\begin{array}{l}
\\
\left(uy \cdot \pi\right) \cdot \left(2 \cdot \sqrt{ux \cdot \left(2 - ux\right)}\right)
\end{array}
Initial program 61.0%
associate-*l*61.0%
sub-neg61.0%
+-commutative61.0%
distribute-rgt-neg-in61.0%
fma-define61.0%
Simplified61.1%
Taylor expanded in ux around 0 98.4%
Taylor expanded in uy around 0 82.4%
Taylor expanded in maxCos around 0 78.9%
associate-*r*78.9%
mul-1-neg78.9%
unsub-neg78.9%
Simplified78.9%
Final simplification78.9%
(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 61.0%
associate-*l*61.0%
sub-neg61.0%
+-commutative61.0%
distribute-rgt-neg-in61.0%
fma-define61.0%
Simplified61.1%
Taylor expanded in uy around 0 52.9%
Simplified53.0%
Taylor expanded in ux around 0 7.1%
Taylor expanded in uy around 0 7.1%
herbie shell --seed 2024110
(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)))))))