
(FPCore (alpha u0) :precision binary32 (* (* (- alpha) alpha) (log (- 1.0 u0))))
float code(float alpha, float u0) {
return (-alpha * alpha) * logf((1.0f - u0));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = (-alpha * alpha) * log((1.0e0 - u0))
end function
function code(alpha, u0) return Float32(Float32(Float32(-alpha) * alpha) * log(Float32(Float32(1.0) - u0))) end
function tmp = code(alpha, u0) tmp = (-alpha * alpha) * log((single(1.0) - u0)); end
\begin{array}{l}
\\
\left(\left(-\alpha\right) \cdot \alpha\right) \cdot \log \left(1 - u0\right)
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 9 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (alpha u0) :precision binary32 (* (* (- alpha) alpha) (log (- 1.0 u0))))
float code(float alpha, float u0) {
return (-alpha * alpha) * logf((1.0f - u0));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = (-alpha * alpha) * log((1.0e0 - u0))
end function
function code(alpha, u0) return Float32(Float32(Float32(-alpha) * alpha) * log(Float32(Float32(1.0) - u0))) end
function tmp = code(alpha, u0) tmp = (-alpha * alpha) * log((single(1.0) - u0)); end
\begin{array}{l}
\\
\left(\left(-\alpha\right) \cdot \alpha\right) \cdot \log \left(1 - u0\right)
\end{array}
(FPCore (alpha u0) :precision binary32 (* alpha (* (- alpha) (log1p (- u0)))))
float code(float alpha, float u0) {
return alpha * (-alpha * log1pf(-u0));
}
function code(alpha, u0) return Float32(alpha * Float32(Float32(-alpha) * log1p(Float32(-u0)))) end
\begin{array}{l}
\\
\alpha \cdot \left(\left(-\alpha\right) \cdot \mathsf{log1p}\left(-u0\right)\right)
\end{array}
Initial program 56.3%
associate-*l*56.3%
sub-neg56.3%
log1p-def99.0%
Simplified99.0%
Final simplification99.0%
(FPCore (alpha u0) :precision binary32 (* (* alpha alpha) (+ u0 (* (* u0 u0) (+ 0.5 (* u0 0.3333333333333333))))))
float code(float alpha, float u0) {
return (alpha * alpha) * (u0 + ((u0 * u0) * (0.5f + (u0 * 0.3333333333333333f))));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = (alpha * alpha) * (u0 + ((u0 * u0) * (0.5e0 + (u0 * 0.3333333333333333e0))))
end function
function code(alpha, u0) return Float32(Float32(alpha * alpha) * Float32(u0 + Float32(Float32(u0 * u0) * Float32(Float32(0.5) + Float32(u0 * Float32(0.3333333333333333)))))) end
function tmp = code(alpha, u0) tmp = (alpha * alpha) * (u0 + ((u0 * u0) * (single(0.5) + (u0 * single(0.3333333333333333))))); end
\begin{array}{l}
\\
\left(\alpha \cdot \alpha\right) \cdot \left(u0 + \left(u0 \cdot u0\right) \cdot \left(0.5 + u0 \cdot 0.3333333333333333\right)\right)
\end{array}
Initial program 56.3%
associate-*l*56.3%
sub-neg56.3%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 91.9%
*-commutative91.9%
+-commutative91.9%
associate-*r*91.9%
associate-*r*91.9%
distribute-rgt-out91.9%
distribute-lft-out91.8%
unpow291.8%
cube-mult91.8%
unpow291.8%
associate-*r*91.8%
distribute-rgt-out91.8%
unpow291.8%
Simplified91.8%
Final simplification91.8%
(FPCore (alpha u0) :precision binary32 (* alpha (* alpha (- u0 (* (* u0 u0) (+ -0.5 (* u0 -0.3333333333333333)))))))
float code(float alpha, float u0) {
return alpha * (alpha * (u0 - ((u0 * u0) * (-0.5f + (u0 * -0.3333333333333333f)))));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = alpha * (alpha * (u0 - ((u0 * u0) * ((-0.5e0) + (u0 * (-0.3333333333333333e0))))))
end function
function code(alpha, u0) return Float32(alpha * Float32(alpha * Float32(u0 - Float32(Float32(u0 * u0) * Float32(Float32(-0.5) + Float32(u0 * Float32(-0.3333333333333333))))))) end
function tmp = code(alpha, u0) tmp = alpha * (alpha * (u0 - ((u0 * u0) * (single(-0.5) + (u0 * single(-0.3333333333333333)))))); end
\begin{array}{l}
\\
\alpha \cdot \left(\alpha \cdot \left(u0 - \left(u0 \cdot u0\right) \cdot \left(-0.5 + u0 \cdot -0.3333333333333333\right)\right)\right)
\end{array}
Initial program 56.3%
associate-*l*56.3%
sub-neg56.3%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 91.8%
associate-+r+91.8%
+-commutative91.8%
associate-*r*91.8%
*-commutative91.8%
associate-*r*91.8%
associate-*r*91.8%
distribute-rgt-out91.9%
distribute-lft-out91.9%
associate-+l+92.0%
mul-1-neg92.0%
unsub-neg92.0%
*-commutative92.0%
*-commutative92.0%
unpow392.0%
unpow292.0%
associate-*l*92.0%
distribute-lft-out92.0%
unpow292.0%
Simplified92.0%
Final simplification92.0%
(FPCore (alpha u0) :precision binary32 (* alpha (* (+ (* u0 0.5) 1.0) (* alpha u0))))
float code(float alpha, float u0) {
return alpha * (((u0 * 0.5f) + 1.0f) * (alpha * u0));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = alpha * (((u0 * 0.5e0) + 1.0e0) * (alpha * u0))
end function
function code(alpha, u0) return Float32(alpha * Float32(Float32(Float32(u0 * Float32(0.5)) + Float32(1.0)) * Float32(alpha * u0))) end
function tmp = code(alpha, u0) tmp = alpha * (((u0 * single(0.5)) + single(1.0)) * (alpha * u0)); end
\begin{array}{l}
\\
\alpha \cdot \left(\left(u0 \cdot 0.5 + 1\right) \cdot \left(\alpha \cdot u0\right)\right)
\end{array}
Initial program 56.3%
associate-*l*56.3%
sub-neg56.3%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 88.2%
associate-*r*88.2%
distribute-rgt-out88.1%
unpow288.1%
*-commutative88.1%
unpow288.1%
Simplified88.1%
distribute-rgt-in88.2%
associate-*l*88.2%
Applied egg-rr88.2%
+-commutative88.2%
associate-*r*88.2%
fma-def88.2%
add-sqr-sqrt87.6%
sqrt-prod88.2%
associate-*r*88.2%
associate-*r*88.3%
swap-sqr87.9%
sqr-neg87.9%
distribute-rgt-neg-out87.9%
distribute-rgt-neg-out87.9%
sqr-neg87.9%
swap-sqr88.3%
*-commutative88.3%
*-commutative88.3%
sqrt-unprod87.6%
add-sqr-sqrt88.3%
Applied egg-rr88.3%
fma-udef88.3%
associate-*l*88.3%
associate-*l*88.3%
associate-*l*88.3%
*-commutative88.3%
associate-*l*88.2%
Applied egg-rr88.2%
associate-*r*88.2%
associate-*r*88.3%
distribute-rgt-out88.2%
associate-*r*88.2%
*-commutative88.2%
associate-*l*88.2%
+-commutative88.2%
*-rgt-identity88.2%
distribute-lft-out88.0%
*-commutative88.0%
*-commutative88.0%
Simplified88.0%
Final simplification88.0%
(FPCore (alpha u0) :precision binary32 (* (* alpha alpha) (* u0 (+ (* u0 0.5) 1.0))))
float code(float alpha, float u0) {
return (alpha * alpha) * (u0 * ((u0 * 0.5f) + 1.0f));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = (alpha * alpha) * (u0 * ((u0 * 0.5e0) + 1.0e0))
end function
function code(alpha, u0) return Float32(Float32(alpha * alpha) * Float32(u0 * Float32(Float32(u0 * Float32(0.5)) + Float32(1.0)))) end
function tmp = code(alpha, u0) tmp = (alpha * alpha) * (u0 * ((u0 * single(0.5)) + single(1.0))); end
\begin{array}{l}
\\
\left(\alpha \cdot \alpha\right) \cdot \left(u0 \cdot \left(u0 \cdot 0.5 + 1\right)\right)
\end{array}
Initial program 56.3%
associate-*l*56.3%
sub-neg56.3%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 88.2%
associate-*r*88.2%
distribute-rgt-out88.1%
unpow288.1%
unpow288.1%
associate-*r*88.1%
distribute-rgt1-in88.1%
Simplified88.1%
Final simplification88.1%
(FPCore (alpha u0) :precision binary32 (* (* alpha alpha) (+ u0 (* (* u0 u0) 0.5))))
float code(float alpha, float u0) {
return (alpha * alpha) * (u0 + ((u0 * u0) * 0.5f));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = (alpha * alpha) * (u0 + ((u0 * u0) * 0.5e0))
end function
function code(alpha, u0) return Float32(Float32(alpha * alpha) * Float32(u0 + Float32(Float32(u0 * u0) * Float32(0.5)))) end
function tmp = code(alpha, u0) tmp = (alpha * alpha) * (u0 + ((u0 * u0) * single(0.5))); end
\begin{array}{l}
\\
\left(\alpha \cdot \alpha\right) \cdot \left(u0 + \left(u0 \cdot u0\right) \cdot 0.5\right)
\end{array}
Initial program 56.3%
associate-*l*56.3%
sub-neg56.3%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 88.2%
associate-*r*88.2%
distribute-rgt-out88.1%
unpow288.1%
*-commutative88.1%
unpow288.1%
Simplified88.1%
Final simplification88.1%
(FPCore (alpha u0) :precision binary32 (* alpha (* alpha (- u0 (* u0 (* u0 -0.5))))))
float code(float alpha, float u0) {
return alpha * (alpha * (u0 - (u0 * (u0 * -0.5f))));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = alpha * (alpha * (u0 - (u0 * (u0 * (-0.5e0)))))
end function
function code(alpha, u0) return Float32(alpha * Float32(alpha * Float32(u0 - Float32(u0 * Float32(u0 * Float32(-0.5)))))) end
function tmp = code(alpha, u0) tmp = alpha * (alpha * (u0 - (u0 * (u0 * single(-0.5))))); end
\begin{array}{l}
\\
\alpha \cdot \left(\alpha \cdot \left(u0 - u0 \cdot \left(u0 \cdot -0.5\right)\right)\right)
\end{array}
Initial program 56.3%
associate-*l*56.3%
sub-neg56.3%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 88.2%
+-commutative88.2%
mul-1-neg88.2%
unsub-neg88.2%
associate-*r*88.2%
distribute-rgt-out--88.3%
*-commutative88.3%
unpow288.3%
associate-*l*88.3%
Simplified88.3%
Final simplification88.3%
(FPCore (alpha u0) :precision binary32 (* u0 (* alpha alpha)))
float code(float alpha, float u0) {
return u0 * (alpha * alpha);
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = u0 * (alpha * alpha)
end function
function code(alpha, u0) return Float32(u0 * Float32(alpha * alpha)) end
function tmp = code(alpha, u0) tmp = u0 * (alpha * alpha); end
\begin{array}{l}
\\
u0 \cdot \left(\alpha \cdot \alpha\right)
\end{array}
Initial program 56.3%
associate-*l*56.3%
sub-neg56.3%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 74.9%
unpow274.9%
Simplified74.9%
Final simplification74.9%
(FPCore (alpha u0) :precision binary32 (* alpha (* alpha u0)))
float code(float alpha, float u0) {
return alpha * (alpha * u0);
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = alpha * (alpha * u0)
end function
function code(alpha, u0) return Float32(alpha * Float32(alpha * u0)) end
function tmp = code(alpha, u0) tmp = alpha * (alpha * u0); end
\begin{array}{l}
\\
\alpha \cdot \left(\alpha \cdot u0\right)
\end{array}
Initial program 56.3%
associate-*l*56.3%
sub-neg56.3%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 74.9%
unpow274.9%
Simplified74.9%
add-cbrt-cube67.7%
Applied egg-rr67.7%
add-cbrt-cube74.9%
associate-*r*75.0%
Applied egg-rr75.0%
Final simplification75.0%
herbie shell --seed 2023257
(FPCore (alpha u0)
:name "Beckmann Distribution sample, tan2theta, alphax == alphay"
:precision binary32
:pre (and (and (<= 0.0001 alpha) (<= alpha 1.0)) (and (<= 2.328306437e-10 u0) (<= u0 1.0)))
(* (* (- alpha) alpha) (log (- 1.0 u0))))