
(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 11 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
(let* ((t_0 (+ (* alpha alpha) -1.0)))
(/
t_0
(* (log (pow (* alpha alpha) PI)) (+ 1.0 (* cosTheta (* t_0 cosTheta)))))))
float code(float cosTheta, float alpha) {
float t_0 = (alpha * alpha) + -1.0f;
return t_0 / (logf(powf((alpha * alpha), ((float) M_PI))) * (1.0f + (cosTheta * (t_0 * cosTheta))));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(alpha * alpha) + Float32(-1.0)) return Float32(t_0 / Float32(log((Float32(alpha * alpha) ^ Float32(pi))) * Float32(Float32(1.0) + Float32(cosTheta * Float32(t_0 * cosTheta))))) end
function tmp = code(cosTheta, alpha) t_0 = (alpha * alpha) + single(-1.0); tmp = t_0 / (log(((alpha * alpha) ^ single(pi))) * (single(1.0) + (cosTheta * (t_0 * cosTheta)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha + -1\\
\frac{t_0}{\log \left({\left(\alpha \cdot \alpha\right)}^{\pi}\right) \cdot \left(1 + cosTheta \cdot \left(t_0 \cdot cosTheta\right)\right)}
\end{array}
\end{array}
Initial program 98.7%
add-log-exp98.7%
*-commutative98.7%
exp-to-pow98.8%
Applied egg-rr98.8%
Final simplification98.8%
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (+ (* alpha alpha) -1.0)))
(/
t_0
(* (+ 1.0 (* cosTheta (* t_0 cosTheta))) (* PI (log (* alpha alpha)))))))
float code(float cosTheta, float alpha) {
float t_0 = (alpha * alpha) + -1.0f;
return t_0 / ((1.0f + (cosTheta * (t_0 * cosTheta))) * (((float) M_PI) * logf((alpha * alpha))));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(alpha * alpha) + Float32(-1.0)) return Float32(t_0 / Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(t_0 * cosTheta))) * Float32(Float32(pi) * log(Float32(alpha * alpha))))) end
function tmp = code(cosTheta, alpha) t_0 = (alpha * alpha) + single(-1.0); tmp = t_0 / ((single(1.0) + (cosTheta * (t_0 * cosTheta))) * (single(pi) * log((alpha * alpha)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha + -1\\
\frac{t_0}{\left(1 + cosTheta \cdot \left(t_0 \cdot cosTheta\right)\right) \cdot \left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right)}
\end{array}
\end{array}
Initial program 98.7%
Final simplification98.7%
(FPCore (cosTheta alpha) :precision binary32 (/ (- 1.0 (* alpha alpha)) (* PI (* (- 1.0 (* cosTheta cosTheta)) (* (log alpha) -2.0)))))
float code(float cosTheta, float alpha) {
return (1.0f - (alpha * alpha)) / (((float) M_PI) * ((1.0f - (cosTheta * cosTheta)) * (logf(alpha) * -2.0f)));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(1.0) - Float32(alpha * alpha)) / Float32(Float32(pi) * Float32(Float32(Float32(1.0) - Float32(cosTheta * cosTheta)) * Float32(log(alpha) * Float32(-2.0))))) end
function tmp = code(cosTheta, alpha) tmp = (single(1.0) - (alpha * alpha)) / (single(pi) * ((single(1.0) - (cosTheta * cosTheta)) * (log(alpha) * single(-2.0)))); end
\begin{array}{l}
\\
\frac{1 - \alpha \cdot \alpha}{\pi \cdot \left(\left(1 - cosTheta \cdot cosTheta\right) \cdot \left(\log \alpha \cdot -2\right)\right)}
\end{array}
Initial program 98.7%
associate-/r*98.8%
associate-/r*98.5%
log-prod98.4%
count-298.4%
fma-neg98.4%
metadata-eval98.4%
*-commutative98.4%
+-commutative98.4%
associate-*l*98.4%
fma-def98.4%
fma-neg98.4%
metadata-eval98.4%
Simplified98.4%
Taylor expanded in alpha around 0 96.8%
clear-num96.7%
inv-pow96.8%
Applied egg-rr96.8%
Simplified96.7%
div-inv96.7%
metadata-eval96.7%
fma-neg96.7%
associate-/r/96.5%
fma-neg96.6%
metadata-eval96.6%
mul-1-neg96.6%
unpow296.6%
Applied egg-rr96.6%
un-div-inv96.6%
associate-*l/96.8%
*-un-lft-identity96.8%
associate-/l/97.1%
*-commutative97.1%
distribute-lft-neg-in97.1%
associate-/r*97.1%
frac-2neg97.1%
associate-*l*97.1%
distribute-lft-neg-in97.1%
+-commutative97.1%
distribute-rgt-neg-in97.1%
fma-def97.1%
Applied egg-rr97.1%
neg-sub097.1%
metadata-eval97.1%
fma-def97.1%
unpow297.1%
+-commutative97.1%
associate--r+97.1%
metadata-eval97.1%
metadata-eval97.1%
unpow297.1%
distribute-rgt-neg-in97.1%
*-commutative97.1%
fma-udef97.1%
distribute-rgt-neg-out97.1%
unpow297.1%
mul-1-neg97.1%
+-commutative97.1%
distribute-rgt-neg-in97.1%
mul-1-neg97.1%
sub-neg97.1%
unpow297.1%
Simplified97.1%
Final simplification97.1%
(FPCore (cosTheta alpha) :precision binary32 (/ (+ (* alpha alpha) -1.0) (* (* 2.0 (log alpha)) (* PI (- 1.0 (* cosTheta cosTheta))))))
float code(float cosTheta, float alpha) {
return ((alpha * alpha) + -1.0f) / ((2.0f * logf(alpha)) * (((float) M_PI) * (1.0f - (cosTheta * cosTheta))));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(alpha * alpha) + Float32(-1.0)) / Float32(Float32(Float32(2.0) * log(alpha)) * Float32(Float32(pi) * Float32(Float32(1.0) - Float32(cosTheta * cosTheta))))) end
function tmp = code(cosTheta, alpha) tmp = ((alpha * alpha) + single(-1.0)) / ((single(2.0) * log(alpha)) * (single(pi) * (single(1.0) - (cosTheta * cosTheta)))); end
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha + -1}{\left(2 \cdot \log \alpha\right) \cdot \left(\pi \cdot \left(1 - cosTheta \cdot cosTheta\right)\right)}
\end{array}
Initial program 98.7%
pow298.7%
log-pow98.7%
*-commutative98.7%
Applied egg-rr98.7%
Taylor expanded in alpha around 0 97.1%
Simplified97.1%
Taylor expanded in alpha around 0 97.1%
associate-*r*97.1%
mul-1-neg97.1%
sub-neg97.1%
unpow297.1%
Simplified97.1%
Final simplification97.1%
(FPCore (cosTheta alpha) :precision binary32 (/ (+ (* alpha alpha) -1.0) (* (* PI (log (* alpha alpha))) (- 1.0 (* cosTheta cosTheta)))))
float code(float cosTheta, float alpha) {
return ((alpha * alpha) + -1.0f) / ((((float) M_PI) * logf((alpha * alpha))) * (1.0f - (cosTheta * cosTheta)));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(alpha * alpha) + Float32(-1.0)) / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(Float32(1.0) - Float32(cosTheta * cosTheta)))) end
function tmp = code(cosTheta, alpha) tmp = ((alpha * alpha) + single(-1.0)) / ((single(pi) * log((alpha * alpha))) * (single(1.0) - (cosTheta * cosTheta))); end
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha + -1}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 - cosTheta \cdot cosTheta\right)}
\end{array}
Initial program 98.7%
pow298.7%
log-pow98.7%
*-commutative98.7%
Applied egg-rr98.7%
Taylor expanded in alpha around 0 97.1%
Simplified97.1%
add-log-exp97.1%
distribute-lft-neg-in97.1%
exp-prod97.1%
*-commutative97.1%
*-commutative97.1%
log-pow97.2%
pow297.2%
exp-to-pow97.3%
+-commutative97.3%
distribute-rgt-neg-in97.3%
fma-def97.3%
Applied egg-rr97.3%
log-pow97.2%
fma-udef97.3%
distribute-rgt-neg-out97.3%
unpow297.3%
mul-1-neg97.3%
+-commutative97.3%
mul-1-neg97.3%
sub-neg97.3%
unpow297.3%
unpow297.3%
log-pow97.2%
unpow297.2%
Simplified97.2%
Final simplification97.2%
(FPCore (cosTheta alpha) :precision binary32 (/ -0.5 (* (log alpha) (* PI (- 1.0 (* cosTheta cosTheta))))))
float code(float cosTheta, float alpha) {
return -0.5f / (logf(alpha) * (((float) M_PI) * (1.0f - (cosTheta * cosTheta))));
}
function code(cosTheta, alpha) return Float32(Float32(-0.5) / Float32(log(alpha) * Float32(Float32(pi) * Float32(Float32(1.0) - Float32(cosTheta * cosTheta))))) end
function tmp = code(cosTheta, alpha) tmp = single(-0.5) / (log(alpha) * (single(pi) * (single(1.0) - (cosTheta * cosTheta)))); end
\begin{array}{l}
\\
\frac{-0.5}{\log \alpha \cdot \left(\pi \cdot \left(1 - cosTheta \cdot cosTheta\right)\right)}
\end{array}
Initial program 98.7%
add-log-exp98.7%
*-commutative98.7%
exp-to-pow98.8%
Applied egg-rr98.8%
Taylor expanded in alpha around 0 66.9%
*-commutative66.9%
neg-mul-166.9%
unsub-neg66.9%
unpow266.9%
Simplified66.9%
Final simplification66.9%
(FPCore (cosTheta alpha) :precision binary32 (/ -0.5 (* (- 1.0 (* cosTheta cosTheta)) (* PI (log alpha)))))
float code(float cosTheta, float alpha) {
return -0.5f / ((1.0f - (cosTheta * cosTheta)) * (((float) M_PI) * logf(alpha)));
}
function code(cosTheta, alpha) return Float32(Float32(-0.5) / Float32(Float32(Float32(1.0) - Float32(cosTheta * cosTheta)) * Float32(Float32(pi) * log(alpha)))) end
function tmp = code(cosTheta, alpha) tmp = single(-0.5) / ((single(1.0) - (cosTheta * cosTheta)) * (single(pi) * log(alpha))); end
\begin{array}{l}
\\
\frac{-0.5}{\left(1 - cosTheta \cdot cosTheta\right) \cdot \left(\pi \cdot \log \alpha\right)}
\end{array}
Initial program 98.7%
associate-/r*98.8%
associate-/r*98.5%
log-prod98.4%
count-298.4%
fma-neg98.4%
metadata-eval98.4%
*-commutative98.4%
+-commutative98.4%
associate-*l*98.4%
fma-def98.4%
fma-neg98.4%
metadata-eval98.4%
Simplified98.4%
fma-udef98.4%
Applied egg-rr98.4%
Taylor expanded in alpha around 0 66.9%
mul-1-neg66.9%
sub-neg66.9%
*-commutative66.9%
sub-neg66.9%
mul-1-neg66.9%
associate-*r*66.9%
mul-1-neg66.9%
sub-neg66.9%
*-commutative66.9%
unpow266.9%
Simplified66.9%
Final simplification66.9%
(FPCore (cosTheta alpha) :precision binary32 (/ (+ (* alpha alpha) -1.0) (* 2.0 (* PI (log alpha)))))
float code(float cosTheta, float alpha) {
return ((alpha * alpha) + -1.0f) / (2.0f * (((float) M_PI) * logf(alpha)));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(alpha * alpha) + Float32(-1.0)) / Float32(Float32(2.0) * Float32(Float32(pi) * log(alpha)))) end
function tmp = code(cosTheta, alpha) tmp = ((alpha * alpha) + single(-1.0)) / (single(2.0) * (single(pi) * log(alpha))); end
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha + -1}{2 \cdot \left(\pi \cdot \log \alpha\right)}
\end{array}
Initial program 98.7%
pow298.7%
log-pow98.7%
*-commutative98.7%
Applied egg-rr98.7%
Taylor expanded in alpha around 0 97.1%
Simplified97.1%
Taylor expanded in cosTheta around 0 93.5%
Final simplification93.5%
(FPCore (cosTheta alpha) :precision binary32 (/ 1.0 (/ PI (/ -0.5 (log alpha)))))
float code(float cosTheta, float alpha) {
return 1.0f / (((float) M_PI) / (-0.5f / logf(alpha)));
}
function code(cosTheta, alpha) return Float32(Float32(1.0) / Float32(Float32(pi) / Float32(Float32(-0.5) / log(alpha)))) end
function tmp = code(cosTheta, alpha) tmp = single(1.0) / (single(pi) / (single(-0.5) / log(alpha))); end
\begin{array}{l}
\\
\frac{1}{\frac{\pi}{\frac{-0.5}{\log \alpha}}}
\end{array}
Initial program 98.7%
Taylor expanded in cosTheta around 0 93.6%
Simplified93.5%
Taylor expanded in alpha around 0 64.4%
clear-num64.4%
inv-pow64.4%
*-commutative64.4%
Applied egg-rr64.4%
unpow-164.4%
associate-/l*64.5%
Simplified64.5%
Final simplification64.5%
(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 98.7%
Taylor expanded in cosTheta around 0 93.6%
Simplified93.5%
Taylor expanded in alpha around 0 64.4%
Final simplification64.4%
(FPCore (cosTheta alpha) :precision binary32 (/ (/ -0.5 (log alpha)) PI))
float code(float cosTheta, float alpha) {
return (-0.5f / logf(alpha)) / ((float) M_PI);
}
function code(cosTheta, alpha) return Float32(Float32(Float32(-0.5) / log(alpha)) / Float32(pi)) end
function tmp = code(cosTheta, alpha) tmp = (single(-0.5) / log(alpha)) / single(pi); end
\begin{array}{l}
\\
\frac{\frac{-0.5}{\log \alpha}}{\pi}
\end{array}
Initial program 98.7%
Taylor expanded in cosTheta around 0 93.6%
Simplified93.5%
Taylor expanded in alpha around 0 64.4%
associate-/r*64.5%
Simplified64.5%
Final simplification64.5%
herbie shell --seed 2023279
(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)))))