
(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 10 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 (* (- 0.0 (* alpha alpha)) (log1p (- u0))))
float code(float alpha, float u0) {
return (0.0f - (alpha * alpha)) * log1pf(-u0);
}
function code(alpha, u0) return Float32(Float32(Float32(0.0) - Float32(alpha * alpha)) * log1p(Float32(-u0))) end
\begin{array}{l}
\\
\left(0 - \alpha \cdot \alpha\right) \cdot \mathsf{log1p}\left(-u0\right)
\end{array}
Initial program 55.8%
sub-negN/A
accelerator-lowering-log1p.f32N/A
neg-lowering-neg.f3299.0
Applied egg-rr99.0%
Final simplification99.0%
(FPCore (alpha u0)
:precision binary32
(*
u0
(fma
u0
(*
(fma alpha alpha 0.0)
(fma u0 (* u0 0.25) (fma u0 0.3333333333333333 0.5)))
(fma alpha alpha 0.0))))
float code(float alpha, float u0) {
return u0 * fmaf(u0, (fmaf(alpha, alpha, 0.0f) * fmaf(u0, (u0 * 0.25f), fmaf(u0, 0.3333333333333333f, 0.5f))), fmaf(alpha, alpha, 0.0f));
}
function code(alpha, u0) return Float32(u0 * fma(u0, Float32(fma(alpha, alpha, Float32(0.0)) * fma(u0, Float32(u0 * Float32(0.25)), fma(u0, Float32(0.3333333333333333), Float32(0.5)))), fma(alpha, alpha, Float32(0.0)))) end
\begin{array}{l}
\\
u0 \cdot \mathsf{fma}\left(u0, \mathsf{fma}\left(\alpha, \alpha, 0\right) \cdot \mathsf{fma}\left(u0, u0 \cdot 0.25, \mathsf{fma}\left(u0, 0.3333333333333333, 0.5\right)\right), \mathsf{fma}\left(\alpha, \alpha, 0\right)\right)
\end{array}
Initial program 55.8%
Taylor expanded in u0 around 0
*-lowering-*.f32N/A
accelerator-lowering-fma.f32N/A
Simplified93.6%
(FPCore (alpha u0) :precision binary32 (* (* alpha alpha) (* u0 (fma u0 (fma u0 (fma u0 0.25 0.3333333333333333) 0.5) 1.0))))
float code(float alpha, float u0) {
return (alpha * alpha) * (u0 * fmaf(u0, fmaf(u0, fmaf(u0, 0.25f, 0.3333333333333333f), 0.5f), 1.0f));
}
function code(alpha, u0) return Float32(Float32(alpha * alpha) * Float32(u0 * fma(u0, fma(u0, fma(u0, Float32(0.25), Float32(0.3333333333333333)), Float32(0.5)), Float32(1.0)))) end
\begin{array}{l}
\\
\left(\alpha \cdot \alpha\right) \cdot \left(u0 \cdot \mathsf{fma}\left(u0, \mathsf{fma}\left(u0, \mathsf{fma}\left(u0, 0.25, 0.3333333333333333\right), 0.5\right), 1\right)\right)
\end{array}
Initial program 55.8%
sub-negN/A
accelerator-lowering-log1p.f32N/A
neg-lowering-neg.f3299.0
Applied egg-rr99.0%
Applied egg-rr98.8%
Taylor expanded in alpha around 0
mul-1-negN/A
distribute-rgt-neg-inN/A
*-lowering-*.f32N/A
unpow2N/A
*-lowering-*.f32N/A
sub-negN/A
+-commutativeN/A
distribute-neg-inN/A
unsub-negN/A
remove-double-negN/A
--lowering--.f32N/A
accelerator-lowering-log1p.f32N/A
sub-negN/A
accelerator-lowering-log1p.f32N/A
neg-sub0N/A
--lowering--.f32N/A
unpow2N/A
*-lowering-*.f3298.8
Simplified98.8%
Taylor expanded in u0 around 0
*-lowering-*.f32N/A
+-commutativeN/A
accelerator-lowering-fma.f32N/A
+-commutativeN/A
accelerator-lowering-fma.f32N/A
+-commutativeN/A
*-commutativeN/A
accelerator-lowering-fma.f3293.2
Simplified93.2%
(FPCore (alpha u0) :precision binary32 (* u0 (fma alpha alpha (* (fma u0 0.3333333333333333 0.5) (* u0 (* alpha alpha))))))
float code(float alpha, float u0) {
return u0 * fmaf(alpha, alpha, (fmaf(u0, 0.3333333333333333f, 0.5f) * (u0 * (alpha * alpha))));
}
function code(alpha, u0) return Float32(u0 * fma(alpha, alpha, Float32(fma(u0, Float32(0.3333333333333333), Float32(0.5)) * Float32(u0 * Float32(alpha * alpha))))) end
\begin{array}{l}
\\
u0 \cdot \mathsf{fma}\left(\alpha, \alpha, \mathsf{fma}\left(u0, 0.3333333333333333, 0.5\right) \cdot \left(u0 \cdot \left(\alpha \cdot \alpha\right)\right)\right)
\end{array}
Initial program 55.8%
sub-negN/A
accelerator-lowering-log1p.f32N/A
neg-lowering-neg.f3299.0
Applied egg-rr99.0%
Taylor expanded in u0 around 0
*-lowering-*.f32N/A
+-commutativeN/A
unpow2N/A
accelerator-lowering-fma.f32N/A
distribute-rgt-inN/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
associate-*r*N/A
distribute-rgt-outN/A
+-commutativeN/A
*-lowering-*.f32N/A
*-commutativeN/A
*-lowering-*.f32N/A
unpow2N/A
*-lowering-*.f32N/A
+-commutativeN/A
*-commutativeN/A
accelerator-lowering-fma.f3292.0
Simplified92.0%
Final simplification92.0%
(FPCore (alpha u0) :precision binary32 (* u0 (* (fma alpha alpha 0.0) (fma (fma 0.3333333333333333 u0 0.5) u0 1.0))))
float code(float alpha, float u0) {
return u0 * (fmaf(alpha, alpha, 0.0f) * fmaf(fmaf(0.3333333333333333f, u0, 0.5f), u0, 1.0f));
}
function code(alpha, u0) return Float32(u0 * Float32(fma(alpha, alpha, Float32(0.0)) * fma(fma(Float32(0.3333333333333333), u0, Float32(0.5)), u0, Float32(1.0)))) end
\begin{array}{l}
\\
u0 \cdot \left(\mathsf{fma}\left(\alpha, \alpha, 0\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(0.3333333333333333, u0, 0.5\right), u0, 1\right)\right)
\end{array}
Initial program 55.8%
Taylor expanded in u0 around 0
distribute-rgt-inN/A
associate-*r*N/A
associate-+l+N/A
distribute-lft-inN/A
*-commutativeN/A
associate-*r*N/A
associate-*r*N/A
*-commutativeN/A
distribute-lft-inN/A
associate-*r*N/A
*-commutativeN/A
distribute-lft1-inN/A
Simplified91.5%
associate-+r+N/A
+-lowering-+.f32N/A
distribute-lft-outN/A
*-lowering-*.f32N/A
accelerator-lowering-fma.f3291.5
Applied egg-rr91.5%
Applied egg-rr91.6%
Final simplification91.6%
(FPCore (alpha u0) :precision binary32 (* u0 (* alpha (* alpha (fma u0 (fma u0 0.3333333333333333 0.5) 1.0)))))
float code(float alpha, float u0) {
return u0 * (alpha * (alpha * fmaf(u0, fmaf(u0, 0.3333333333333333f, 0.5f), 1.0f)));
}
function code(alpha, u0) return Float32(u0 * Float32(alpha * Float32(alpha * fma(u0, fma(u0, Float32(0.3333333333333333), Float32(0.5)), Float32(1.0))))) end
\begin{array}{l}
\\
u0 \cdot \left(\alpha \cdot \left(\alpha \cdot \mathsf{fma}\left(u0, \mathsf{fma}\left(u0, 0.3333333333333333, 0.5\right), 1\right)\right)\right)
\end{array}
Initial program 55.8%
Taylor expanded in u0 around 0
distribute-rgt-inN/A
associate-*r*N/A
associate-+l+N/A
distribute-lft-inN/A
*-commutativeN/A
associate-*r*N/A
associate-*r*N/A
*-commutativeN/A
distribute-lft-inN/A
associate-*r*N/A
*-commutativeN/A
distribute-lft1-inN/A
Simplified91.5%
+-rgt-identityN/A
associate-*l*N/A
*-commutativeN/A
*-lowering-*.f32N/A
associate-*l*N/A
*-lowering-*.f32N/A
*-lowering-*.f32N/A
associate-+r+N/A
distribute-lft-outN/A
accelerator-lowering-fma.f32N/A
accelerator-lowering-fma.f3291.5
Applied egg-rr91.5%
Final simplification91.5%
(FPCore (alpha u0) :precision binary32 (* (* alpha alpha) (* u0 (fma u0 (fma u0 0.3333333333333333 0.5) 1.0))))
float code(float alpha, float u0) {
return (alpha * alpha) * (u0 * fmaf(u0, fmaf(u0, 0.3333333333333333f, 0.5f), 1.0f));
}
function code(alpha, u0) return Float32(Float32(alpha * alpha) * Float32(u0 * fma(u0, fma(u0, Float32(0.3333333333333333), Float32(0.5)), Float32(1.0)))) end
\begin{array}{l}
\\
\left(\alpha \cdot \alpha\right) \cdot \left(u0 \cdot \mathsf{fma}\left(u0, \mathsf{fma}\left(u0, 0.3333333333333333, 0.5\right), 1\right)\right)
\end{array}
Initial program 55.8%
Taylor expanded in u0 around 0
distribute-rgt-inN/A
associate-*r*N/A
associate-+l+N/A
distribute-lft-inN/A
*-commutativeN/A
associate-*r*N/A
associate-*r*N/A
*-commutativeN/A
distribute-lft-inN/A
associate-*r*N/A
*-commutativeN/A
distribute-lft1-inN/A
Simplified91.5%
Taylor expanded in alpha around 0
*-lowering-*.f32N/A
unpow2N/A
*-lowering-*.f32N/A
*-lowering-*.f32N/A
+-commutativeN/A
associate-+r+N/A
unpow2N/A
associate-*r*N/A
associate-+r+N/A
distribute-rgt-inN/A
+-commutativeN/A
accelerator-lowering-fma.f32N/A
+-commutativeN/A
*-commutativeN/A
accelerator-lowering-fma.f3291.5
Simplified91.5%
(FPCore (alpha u0) :precision binary32 (* alpha (* alpha (* u0 (fma u0 (fma u0 0.3333333333333333 0.5) 1.0)))))
float code(float alpha, float u0) {
return alpha * (alpha * (u0 * fmaf(u0, fmaf(u0, 0.3333333333333333f, 0.5f), 1.0f)));
}
function code(alpha, u0) return Float32(alpha * Float32(alpha * Float32(u0 * fma(u0, fma(u0, Float32(0.3333333333333333), Float32(0.5)), Float32(1.0))))) end
\begin{array}{l}
\\
\alpha \cdot \left(\alpha \cdot \left(u0 \cdot \mathsf{fma}\left(u0, \mathsf{fma}\left(u0, 0.3333333333333333, 0.5\right), 1\right)\right)\right)
\end{array}
Initial program 55.8%
sub-negN/A
accelerator-lowering-log1p.f32N/A
neg-lowering-neg.f3299.0
Applied egg-rr99.0%
Applied egg-rr98.8%
Taylor expanded in u0 around 0
distribute-lft-inN/A
associate-*r*N/A
unpow2N/A
+-commutativeN/A
*-commutativeN/A
associate-*r*N/A
distribute-rgt-inN/A
*-commutativeN/A
associate-*l*N/A
distribute-rgt-inN/A
unpow2N/A
associate-*r*N/A
*-rgt-identityN/A
distribute-lft-inN/A
+-commutativeN/A
associate-*r*N/A
Simplified91.5%
associate-*l*N/A
associate-*l*N/A
*-lowering-*.f32N/A
*-lowering-*.f32N/A
*-lowering-*.f32N/A
accelerator-lowering-fma.f32N/A
accelerator-lowering-fma.f3291.4
Applied egg-rr91.4%
(FPCore (alpha u0) :precision binary32 (* u0 (* (* alpha alpha) (fma u0 0.5 1.0))))
float code(float alpha, float u0) {
return u0 * ((alpha * alpha) * fmaf(u0, 0.5f, 1.0f));
}
function code(alpha, u0) return Float32(u0 * Float32(Float32(alpha * alpha) * fma(u0, Float32(0.5), Float32(1.0)))) end
\begin{array}{l}
\\
u0 \cdot \left(\left(\alpha \cdot \alpha\right) \cdot \mathsf{fma}\left(u0, 0.5, 1\right)\right)
\end{array}
Initial program 55.8%
sub-negN/A
accelerator-lowering-log1p.f32N/A
neg-lowering-neg.f3299.0
Applied egg-rr99.0%
Taylor expanded in u0 around 0
*-lowering-*.f32N/A
*-commutativeN/A
associate-*r*N/A
distribute-lft1-inN/A
lft-mult-inverseN/A
distribute-rgt-inN/A
*-lowering-*.f32N/A
distribute-lft-inN/A
rgt-mult-inverseN/A
accelerator-lowering-fma.f32N/A
unpow2N/A
*-lowering-*.f3288.0
Simplified88.0%
Final simplification88.0%
(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 55.8%
Taylor expanded in u0 around 0
*-commutativeN/A
*-lowering-*.f32N/A
--rgt-identityN/A
sub-negN/A
unpow2N/A
metadata-evalN/A
accelerator-lowering-fma.f3275.2
Simplified75.2%
+-rgt-identityN/A
*-lowering-*.f3275.2
Applied egg-rr75.2%
herbie shell --seed 2024198
(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))))