
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(* (* PI (log (* alpha alpha))) (+ 1.0 (* (* t_0 cosTheta) cosTheta))))))
float code(float cosTheta, float alpha) {
float t_0 = (alpha * alpha) - 1.0f;
return t_0 / ((((float) M_PI) * logf((alpha * alpha))) * (1.0f + ((t_0 * cosTheta) * cosTheta)));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(alpha * alpha) - Float32(1.0)) return Float32(t_0 / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(Float32(1.0) + Float32(Float32(t_0 * cosTheta) * cosTheta)))) end
function tmp = code(cosTheta, alpha) t_0 = (alpha * alpha) - single(1.0); tmp = t_0 / ((single(pi) * log((alpha * alpha))) * (single(1.0) + ((t_0 * cosTheta) * cosTheta))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t\_0}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 + \left(t\_0 \cdot cosTheta\right) \cdot cosTheta\right)}
\end{array}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 12 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(* (* PI (log (* alpha alpha))) (+ 1.0 (* (* t_0 cosTheta) cosTheta))))))
float code(float cosTheta, float alpha) {
float t_0 = (alpha * alpha) - 1.0f;
return t_0 / ((((float) M_PI) * logf((alpha * alpha))) * (1.0f + ((t_0 * cosTheta) * cosTheta)));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(alpha * alpha) - Float32(1.0)) return Float32(t_0 / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(Float32(1.0) + Float32(Float32(t_0 * cosTheta) * cosTheta)))) end
function tmp = code(cosTheta, alpha) t_0 = (alpha * alpha) - single(1.0); tmp = t_0 / ((single(pi) * log((alpha * alpha))) * (single(1.0) + ((t_0 * cosTheta) * cosTheta))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t\_0}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 + \left(t\_0 \cdot cosTheta\right) \cdot cosTheta\right)}
\end{array}
\end{array}
(FPCore (cosTheta alpha) :precision binary32 (/ (pow (* PI (/ (* 2.0 (log alpha)) (fma alpha alpha -1.0))) -1.0) (fma (fma alpha alpha -1.0) (* cosTheta cosTheta) 1.0)))
float code(float cosTheta, float alpha) {
return powf((((float) M_PI) * ((2.0f * logf(alpha)) / fmaf(alpha, alpha, -1.0f))), -1.0f) / fmaf(fmaf(alpha, alpha, -1.0f), (cosTheta * cosTheta), 1.0f);
}
function code(cosTheta, alpha) return Float32((Float32(Float32(pi) * Float32(Float32(Float32(2.0) * log(alpha)) / fma(alpha, alpha, Float32(-1.0)))) ^ Float32(-1.0)) / fma(fma(alpha, alpha, Float32(-1.0)), Float32(cosTheta * cosTheta), Float32(1.0))) end
\begin{array}{l}
\\
\frac{{\left(\pi \cdot \frac{2 \cdot \log \alpha}{\mathsf{fma}\left(\alpha, \alpha, -1\right)}\right)}^{-1}}{\mathsf{fma}\left(\mathsf{fma}\left(\alpha, \alpha, -1\right), cosTheta \cdot cosTheta, 1\right)}
\end{array}
Initial program 98.4%
associate-/r*98.5%
fmm-def98.5%
metadata-eval98.5%
+-commutative98.5%
associate-*l*98.5%
fma-define98.5%
fmm-def98.5%
metadata-eval98.5%
Simplified98.5%
clear-num98.3%
inv-pow98.3%
associate-/l*98.5%
pow298.5%
log-pow98.6%
Applied egg-rr98.6%
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (+ -1.0 (* alpha alpha))))
(/
t_0
(* (log (pow (* alpha alpha) PI)) (+ 1.0 (* cosTheta (* cosTheta t_0)))))))
float code(float cosTheta, float alpha) {
float t_0 = -1.0f + (alpha * alpha);
return t_0 / (logf(powf((alpha * alpha), ((float) M_PI))) * (1.0f + (cosTheta * (cosTheta * t_0))));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(-1.0) + Float32(alpha * alpha)) return Float32(t_0 / Float32(log((Float32(alpha * alpha) ^ Float32(pi))) * Float32(Float32(1.0) + Float32(cosTheta * Float32(cosTheta * t_0))))) end
function tmp = code(cosTheta, alpha) t_0 = single(-1.0) + (alpha * alpha); tmp = t_0 / (log(((alpha * alpha) ^ single(pi))) * (single(1.0) + (cosTheta * (cosTheta * t_0)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := -1 + \alpha \cdot \alpha\\
\frac{t\_0}{\log \left({\left(\alpha \cdot \alpha\right)}^{\pi}\right) \cdot \left(1 + cosTheta \cdot \left(cosTheta \cdot t\_0\right)\right)}
\end{array}
\end{array}
Initial program 98.4%
*-commutative98.4%
add-log-exp98.4%
exp-to-pow98.5%
pow298.5%
Applied egg-rr98.5%
pow298.5%
Applied egg-rr98.5%
Final simplification98.5%
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (+ -1.0 (* alpha alpha))))
(/
t_0
(* (+ 1.0 (* cosTheta (* cosTheta t_0))) (* PI (* 2.0 (log alpha)))))))
float code(float cosTheta, float alpha) {
float t_0 = -1.0f + (alpha * alpha);
return t_0 / ((1.0f + (cosTheta * (cosTheta * t_0))) * (((float) M_PI) * (2.0f * logf(alpha))));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(-1.0) + Float32(alpha * alpha)) return Float32(t_0 / Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(cosTheta * t_0))) * Float32(Float32(pi) * Float32(Float32(2.0) * log(alpha))))) end
function tmp = code(cosTheta, alpha) t_0 = single(-1.0) + (alpha * alpha); tmp = t_0 / ((single(1.0) + (cosTheta * (cosTheta * t_0))) * (single(pi) * (single(2.0) * log(alpha)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := -1 + \alpha \cdot \alpha\\
\frac{t\_0}{\left(1 + cosTheta \cdot \left(cosTheta \cdot t\_0\right)\right) \cdot \left(\pi \cdot \left(2 \cdot \log \alpha\right)\right)}
\end{array}
\end{array}
Initial program 98.4%
Taylor expanded in alpha around 0 98.5%
Final simplification98.5%
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (+ -1.0 (* alpha alpha))))
(/
t_0
(* (+ 1.0 (* cosTheta (* cosTheta t_0))) (* PI (log (* alpha alpha)))))))
float code(float cosTheta, float alpha) {
float t_0 = -1.0f + (alpha * alpha);
return t_0 / ((1.0f + (cosTheta * (cosTheta * t_0))) * (((float) M_PI) * logf((alpha * alpha))));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(-1.0) + Float32(alpha * alpha)) return Float32(t_0 / Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(cosTheta * t_0))) * Float32(Float32(pi) * log(Float32(alpha * alpha))))) end
function tmp = code(cosTheta, alpha) t_0 = single(-1.0) + (alpha * alpha); tmp = t_0 / ((single(1.0) + (cosTheta * (cosTheta * t_0))) * (single(pi) * log((alpha * alpha)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := -1 + \alpha \cdot \alpha\\
\frac{t\_0}{\left(1 + cosTheta \cdot \left(cosTheta \cdot t\_0\right)\right) \cdot \left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right)}
\end{array}
\end{array}
Initial program 98.4%
Final simplification98.4%
(FPCore (cosTheta alpha) :precision binary32 (/ (+ -1.0 (* alpha alpha)) (* (* PI (* 2.0 (log alpha))) (- 1.0 (* cosTheta cosTheta)))))
float code(float cosTheta, float alpha) {
return (-1.0f + (alpha * alpha)) / ((((float) M_PI) * (2.0f * logf(alpha))) * (1.0f - (cosTheta * cosTheta)));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(-1.0) + Float32(alpha * alpha)) / Float32(Float32(Float32(pi) * Float32(Float32(2.0) * log(alpha))) * Float32(Float32(1.0) - Float32(cosTheta * cosTheta)))) end
function tmp = code(cosTheta, alpha) tmp = (single(-1.0) + (alpha * alpha)) / ((single(pi) * (single(2.0) * log(alpha))) * (single(1.0) - (cosTheta * cosTheta))); end
\begin{array}{l}
\\
\frac{-1 + \alpha \cdot \alpha}{\left(\pi \cdot \left(2 \cdot \log \alpha\right)\right) \cdot \left(1 - cosTheta \cdot cosTheta\right)}
\end{array}
Initial program 98.4%
Taylor expanded in alpha around 0 97.9%
Simplified97.9%
Taylor expanded in alpha around 0 97.9%
Final simplification97.9%
(FPCore (cosTheta alpha) :precision binary32 (/ (+ -1.0 (* alpha alpha)) (* (* PI (log (* alpha alpha))) (- 1.0 (* cosTheta cosTheta)))))
float code(float cosTheta, float alpha) {
return (-1.0f + (alpha * alpha)) / ((((float) M_PI) * logf((alpha * alpha))) * (1.0f - (cosTheta * cosTheta)));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(-1.0) + Float32(alpha * alpha)) / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(Float32(1.0) - Float32(cosTheta * cosTheta)))) end
function tmp = code(cosTheta, alpha) tmp = (single(-1.0) + (alpha * alpha)) / ((single(pi) * log((alpha * alpha))) * (single(1.0) - (cosTheta * cosTheta))); end
\begin{array}{l}
\\
\frac{-1 + \alpha \cdot \alpha}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 - cosTheta \cdot cosTheta\right)}
\end{array}
Initial program 98.4%
Taylor expanded in alpha around 0 97.9%
Simplified97.9%
Final simplification97.9%
(FPCore (cosTheta alpha) :precision binary32 (* 0.5 (/ (+ (- -1.0 alpha) (* alpha (+ alpha 1.0))) (* PI (log alpha)))))
float code(float cosTheta, float alpha) {
return 0.5f * (((-1.0f - alpha) + (alpha * (alpha + 1.0f))) / (((float) M_PI) * logf(alpha)));
}
function code(cosTheta, alpha) return Float32(Float32(0.5) * Float32(Float32(Float32(Float32(-1.0) - alpha) + Float32(alpha * Float32(alpha + Float32(1.0)))) / Float32(Float32(pi) * log(alpha)))) end
function tmp = code(cosTheta, alpha) tmp = single(0.5) * (((single(-1.0) - alpha) + (alpha * (alpha + single(1.0)))) / (single(pi) * log(alpha))); end
\begin{array}{l}
\\
0.5 \cdot \frac{\left(-1 - \alpha\right) + \alpha \cdot \left(\alpha + 1\right)}{\pi \cdot \log \alpha}
\end{array}
Initial program 98.4%
associate-/r*98.5%
fmm-def98.5%
metadata-eval98.5%
+-commutative98.5%
associate-*l*98.5%
fma-define98.5%
fmm-def98.5%
metadata-eval98.5%
Simplified98.5%
fma-undefine98.5%
difference-of-sqr--198.2%
*-commutative98.2%
times-frac98.1%
pow298.1%
log-pow98.1%
sub-neg98.1%
metadata-eval98.1%
Applied egg-rr98.1%
Taylor expanded in cosTheta around 0 95.5%
+-commutative95.5%
sub-neg95.5%
metadata-eval95.5%
distribute-lft-out95.7%
+-commutative95.7%
*-commutative95.7%
Applied egg-rr95.7%
Final simplification95.7%
(FPCore (cosTheta alpha) :precision binary32 (* 0.5 (/ (* (+ alpha 1.0) (+ alpha -1.0)) (* PI (log alpha)))))
float code(float cosTheta, float alpha) {
return 0.5f * (((alpha + 1.0f) * (alpha + -1.0f)) / (((float) M_PI) * logf(alpha)));
}
function code(cosTheta, alpha) return Float32(Float32(0.5) * Float32(Float32(Float32(alpha + Float32(1.0)) * Float32(alpha + Float32(-1.0))) / Float32(Float32(pi) * log(alpha)))) end
function tmp = code(cosTheta, alpha) tmp = single(0.5) * (((alpha + single(1.0)) * (alpha + single(-1.0))) / (single(pi) * log(alpha))); end
\begin{array}{l}
\\
0.5 \cdot \frac{\left(\alpha + 1\right) \cdot \left(\alpha + -1\right)}{\pi \cdot \log \alpha}
\end{array}
Initial program 98.4%
associate-/r*98.5%
fmm-def98.5%
metadata-eval98.5%
+-commutative98.5%
associate-*l*98.5%
fma-define98.5%
fmm-def98.5%
metadata-eval98.5%
Simplified98.5%
fma-undefine98.5%
difference-of-sqr--198.2%
*-commutative98.2%
times-frac98.1%
pow298.1%
log-pow98.1%
sub-neg98.1%
metadata-eval98.1%
Applied egg-rr98.1%
Taylor expanded in cosTheta around 0 95.5%
Final simplification95.5%
(FPCore (cosTheta alpha) :precision binary32 (* 0.5 (* (/ (+ alpha 1.0) PI) (/ (+ alpha -1.0) (log alpha)))))
float code(float cosTheta, float alpha) {
return 0.5f * (((alpha + 1.0f) / ((float) M_PI)) * ((alpha + -1.0f) / logf(alpha)));
}
function code(cosTheta, alpha) return Float32(Float32(0.5) * Float32(Float32(Float32(alpha + Float32(1.0)) / Float32(pi)) * Float32(Float32(alpha + Float32(-1.0)) / log(alpha)))) end
function tmp = code(cosTheta, alpha) tmp = single(0.5) * (((alpha + single(1.0)) / single(pi)) * ((alpha + single(-1.0)) / log(alpha))); end
\begin{array}{l}
\\
0.5 \cdot \left(\frac{\alpha + 1}{\pi} \cdot \frac{\alpha + -1}{\log \alpha}\right)
\end{array}
Initial program 98.4%
associate-/r*98.5%
fmm-def98.5%
metadata-eval98.5%
+-commutative98.5%
associate-*l*98.5%
fma-define98.5%
fmm-def98.5%
metadata-eval98.5%
Simplified98.5%
fma-undefine98.5%
difference-of-sqr--198.2%
*-commutative98.2%
times-frac98.1%
pow298.1%
log-pow98.1%
sub-neg98.1%
metadata-eval98.1%
Applied egg-rr98.1%
Taylor expanded in cosTheta around 0 95.5%
times-frac95.4%
+-commutative95.4%
sub-neg95.4%
metadata-eval95.4%
Applied egg-rr95.4%
(FPCore (cosTheta alpha) :precision binary32 (/ (+ -1.0 (* alpha alpha)) (* PI (log (* alpha alpha)))))
float code(float cosTheta, float alpha) {
return (-1.0f + (alpha * alpha)) / (((float) M_PI) * logf((alpha * alpha)));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(-1.0) + Float32(alpha * alpha)) / Float32(Float32(pi) * log(Float32(alpha * alpha)))) end
function tmp = code(cosTheta, alpha) tmp = (single(-1.0) + (alpha * alpha)) / (single(pi) * log((alpha * alpha))); end
\begin{array}{l}
\\
\frac{-1 + \alpha \cdot \alpha}{\pi \cdot \log \left(\alpha \cdot \alpha\right)}
\end{array}
Initial program 98.4%
Taylor expanded in alpha around 0 97.9%
Simplified97.9%
Taylor expanded in cosTheta around 0 95.6%
Final simplification95.6%
(FPCore (cosTheta alpha) :precision binary32 (/ 0.5 (* PI (log (/ 1.0 alpha)))))
float code(float cosTheta, float alpha) {
return 0.5f / (((float) M_PI) * logf((1.0f / alpha)));
}
function code(cosTheta, alpha) return Float32(Float32(0.5) / Float32(Float32(pi) * log(Float32(Float32(1.0) / alpha)))) end
function tmp = code(cosTheta, alpha) tmp = single(0.5) / (single(pi) * log((single(1.0) / alpha))); end
\begin{array}{l}
\\
\frac{0.5}{\pi \cdot \log \left(\frac{1}{\alpha}\right)}
\end{array}
Initial program 98.4%
associate-/r*98.5%
fmm-def98.5%
metadata-eval98.5%
+-commutative98.5%
associate-*l*98.5%
fma-define98.5%
fmm-def98.5%
metadata-eval98.5%
Simplified98.5%
fma-undefine98.5%
difference-of-sqr--198.2%
*-commutative98.2%
times-frac98.1%
pow298.1%
log-pow98.1%
sub-neg98.1%
metadata-eval98.1%
Applied egg-rr98.1%
Taylor expanded in cosTheta around 0 95.5%
Taylor expanded in alpha around 0 64.7%
Taylor expanded in alpha around inf 64.7%
(FPCore (cosTheta alpha) :precision binary32 (/ -0.5 (* PI (log alpha))))
float code(float cosTheta, float alpha) {
return -0.5f / (((float) M_PI) * logf(alpha));
}
function code(cosTheta, alpha) return Float32(Float32(-0.5) / Float32(Float32(pi) * log(alpha))) end
function tmp = code(cosTheta, alpha) tmp = single(-0.5) / (single(pi) * log(alpha)); end
\begin{array}{l}
\\
\frac{-0.5}{\pi \cdot \log \alpha}
\end{array}
Initial program 98.4%
associate-/r*98.5%
fmm-def98.5%
metadata-eval98.5%
+-commutative98.5%
associate-*l*98.5%
fma-define98.5%
fmm-def98.5%
metadata-eval98.5%
Simplified98.5%
fma-undefine98.5%
difference-of-sqr--198.2%
*-commutative98.2%
times-frac98.1%
pow298.1%
log-pow98.1%
sub-neg98.1%
metadata-eval98.1%
Applied egg-rr98.1%
Taylor expanded in cosTheta around 0 95.5%
Taylor expanded in alpha around 0 64.7%
Taylor expanded in alpha around 0 64.7%
herbie shell --seed 2024160
(FPCore (cosTheta alpha)
:name "GTR1 distribution"
:precision binary32
:pre (and (and (<= 0.0 cosTheta) (<= cosTheta 1.0)) (and (<= 0.0001 alpha) (<= alpha 1.0)))
(/ (- (* alpha alpha) 1.0) (* (* PI (log (* alpha alpha))) (+ 1.0 (* (* (- (* alpha alpha) 1.0) cosTheta) cosTheta)))))