
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
(+ 1.0 c)
(*
(* (/ 1.0 (sqrt PI)) (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta))
(exp (* (- cosTheta) cosTheta))))))
float code(float cosTheta, float c) {
return 1.0f / ((1.0f + c) + (((1.0f / sqrtf(((float) M_PI))) * (sqrtf(((1.0f - cosTheta) - cosTheta)) / cosTheta)) * expf((-cosTheta * cosTheta))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(Float32(1.0) + c) + Float32(Float32(Float32(Float32(1.0) / sqrt(Float32(pi))) * Float32(sqrt(Float32(Float32(Float32(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp(Float32(Float32(-cosTheta) * cosTheta))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / ((single(1.0) + c) + (((single(1.0) / sqrt(single(pi))) * (sqrt(((single(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp((-cosTheta * cosTheta)))); end
\begin{array}{l}
\\
\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 12 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
(+ 1.0 c)
(*
(* (/ 1.0 (sqrt PI)) (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta))
(exp (* (- cosTheta) cosTheta))))))
float code(float cosTheta, float c) {
return 1.0f / ((1.0f + c) + (((1.0f / sqrtf(((float) M_PI))) * (sqrtf(((1.0f - cosTheta) - cosTheta)) / cosTheta)) * expf((-cosTheta * cosTheta))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(Float32(1.0) + c) + Float32(Float32(Float32(Float32(1.0) / sqrt(Float32(pi))) * Float32(sqrt(Float32(Float32(Float32(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp(Float32(Float32(-cosTheta) * cosTheta))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / ((single(1.0) + c) + (((single(1.0) / sqrt(single(pi))) * (sqrt(((single(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp((-cosTheta * cosTheta)))); end
\begin{array}{l}
\\
\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}
\end{array}
(FPCore (cosTheta c) :precision binary32 (/ 1.0 (fma (/ (/ (sqrt (+ 1.0 (* cosTheta -2.0))) cosTheta) (sqrt PI)) (pow (exp cosTheta) (- cosTheta)) (+ 1.0 c))))
float code(float cosTheta, float c) {
return 1.0f / fmaf(((sqrtf((1.0f + (cosTheta * -2.0f))) / cosTheta) / sqrtf(((float) M_PI))), powf(expf(cosTheta), -cosTheta), (1.0f + c));
}
function code(cosTheta, c) return Float32(Float32(1.0) / fma(Float32(Float32(sqrt(Float32(Float32(1.0) + Float32(cosTheta * Float32(-2.0)))) / cosTheta) / sqrt(Float32(pi))), (exp(cosTheta) ^ Float32(-cosTheta)), Float32(Float32(1.0) + c))) end
\begin{array}{l}
\\
\frac{1}{\mathsf{fma}\left(\frac{\frac{\sqrt{1 + cosTheta \cdot -2}}{cosTheta}}{\sqrt{\pi}}, {\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)}, 1 + c\right)}
\end{array}
Initial program 98.0%
+-commutative98.0%
fma-define98.1%
associate-*l/98.6%
*-lft-identity98.6%
sub-neg98.6%
associate--l+98.6%
unsub-neg98.6%
neg-mul-198.6%
neg-mul-198.6%
distribute-rgt-out98.6%
metadata-eval98.6%
*-commutative98.6%
exp-prod98.6%
Simplified98.6%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(/
(exp (- (pow cosTheta 2.0)))
(/ (* cosTheta (sqrt PI)) (sqrt (fma cosTheta -2.0 1.0))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + (expf(-powf(cosTheta, 2.0f)) / ((cosTheta * sqrtf(((float) M_PI))) / sqrtf(fmaf(cosTheta, -2.0f, 1.0f))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(exp(Float32(-(cosTheta ^ Float32(2.0)))) / Float32(Float32(cosTheta * sqrt(Float32(pi))) / sqrt(fma(cosTheta, Float32(-2.0), Float32(1.0)))))))) end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{e^{-{cosTheta}^{2}}}{\frac{cosTheta \cdot \sqrt{\pi}}{\sqrt{\mathsf{fma}\left(cosTheta, -2, 1\right)}}}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
+-commutative98.0%
fma-define98.0%
Simplified98.6%
associate-/l/98.6%
clear-num98.6%
inv-pow98.6%
+-commutative98.6%
fma-define98.6%
Applied egg-rr98.6%
*-un-lft-identity98.6%
unpow-198.6%
associate-/r/98.5%
pow-exp98.6%
distribute-lft-neg-out98.6%
unpow298.6%
Applied egg-rr98.6%
*-lft-identity98.6%
fma-define98.6%
+-commutative98.6%
associate-*l/98.5%
neg-mul-198.5%
*-lft-identity98.5%
neg-mul-198.5%
associate-*l/98.6%
*-commutative98.6%
Simplified98.6%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(*
(/ (exp (* cosTheta (- cosTheta))) cosTheta)
(sqrt (/ (+ 1.0 (* cosTheta -2.0)) PI)))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + ((expf((cosTheta * -cosTheta)) / cosTheta) * sqrtf(((1.0f + (cosTheta * -2.0f)) / ((float) M_PI))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(exp(Float32(cosTheta * Float32(-cosTheta))) / cosTheta) * sqrt(Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(-2.0))) / Float32(pi))))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c + ((exp((cosTheta * -cosTheta)) / cosTheta) * sqrt(((single(1.0) + (cosTheta * single(-2.0))) / single(pi)))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{e^{cosTheta \cdot \left(-cosTheta\right)}}{cosTheta} \cdot \sqrt{\frac{1 + cosTheta \cdot -2}{\pi}}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
+-commutative98.0%
fma-define98.0%
Simplified98.6%
associate-/l/98.6%
clear-num98.6%
inv-pow98.6%
+-commutative98.6%
fma-define98.6%
Applied egg-rr98.6%
*-un-lft-identity98.6%
unpow-198.6%
associate-/r/98.5%
pow-exp98.6%
distribute-lft-neg-out98.6%
unpow298.6%
Applied egg-rr98.6%
*-lft-identity98.6%
fma-define98.6%
+-commutative98.6%
associate-*l/98.5%
neg-mul-198.5%
*-lft-identity98.5%
neg-mul-198.5%
associate-*l/98.6%
*-commutative98.6%
Simplified98.6%
Taylor expanded in c around 0 98.2%
unpow298.2%
Applied egg-rr98.2%
Final simplification98.2%
(FPCore (cosTheta c) :precision binary32 (* cosTheta (- (sqrt PI) (* cosTheta (* PI (+ 1.0 (- c (sqrt (/ 1.0 PI)))))))))
float code(float cosTheta, float c) {
return cosTheta * (sqrtf(((float) M_PI)) - (cosTheta * (((float) M_PI) * (1.0f + (c - sqrtf((1.0f / ((float) M_PI))))))));
}
function code(cosTheta, c) return Float32(cosTheta * Float32(sqrt(Float32(pi)) - Float32(cosTheta * Float32(Float32(pi) * Float32(Float32(1.0) + Float32(c - sqrt(Float32(Float32(1.0) / Float32(pi))))))))) end
function tmp = code(cosTheta, c) tmp = cosTheta * (sqrt(single(pi)) - (cosTheta * (single(pi) * (single(1.0) + (c - sqrt((single(1.0) / single(pi)))))))); end
\begin{array}{l}
\\
cosTheta \cdot \left(\sqrt{\pi} - cosTheta \cdot \left(\pi \cdot \left(1 + \left(c - \sqrt{\frac{1}{\pi}}\right)\right)\right)\right)
\end{array}
Initial program 98.0%
associate-+l+98.0%
+-commutative98.0%
fma-define98.0%
Simplified98.6%
Taylor expanded in cosTheta around 0 96.3%
associate-*r*96.3%
mul-1-neg96.3%
mul-1-neg96.3%
Simplified96.3%
Final simplification96.3%
(FPCore (cosTheta c) :precision binary32 (* cosTheta (+ (sqrt PI) (* (* cosTheta PI) (+ (sqrt (/ 1.0 PI)) (- -1.0 c))))))
float code(float cosTheta, float c) {
return cosTheta * (sqrtf(((float) M_PI)) + ((cosTheta * ((float) M_PI)) * (sqrtf((1.0f / ((float) M_PI))) + (-1.0f - c))));
}
function code(cosTheta, c) return Float32(cosTheta * Float32(sqrt(Float32(pi)) + Float32(Float32(cosTheta * Float32(pi)) * Float32(sqrt(Float32(Float32(1.0) / Float32(pi))) + Float32(Float32(-1.0) - c))))) end
function tmp = code(cosTheta, c) tmp = cosTheta * (sqrt(single(pi)) + ((cosTheta * single(pi)) * (sqrt((single(1.0) / single(pi))) + (single(-1.0) - c)))); end
\begin{array}{l}
\\
cosTheta \cdot \left(\sqrt{\pi} + \left(cosTheta \cdot \pi\right) \cdot \left(\sqrt{\frac{1}{\pi}} + \left(-1 - c\right)\right)\right)
\end{array}
Initial program 98.0%
associate-+l+98.0%
+-commutative98.0%
fma-define98.0%
Simplified98.6%
Taylor expanded in cosTheta around 0 96.3%
mul-1-neg96.3%
unsub-neg96.3%
associate-*r*96.3%
associate-+r+96.3%
mul-1-neg96.3%
unsub-neg96.3%
Simplified96.3%
Final simplification96.3%
(FPCore (cosTheta c) :precision binary32 (* cosTheta (+ (sqrt PI) (* (* cosTheta PI) (+ (sqrt (/ 1.0 PI)) -1.0)))))
float code(float cosTheta, float c) {
return cosTheta * (sqrtf(((float) M_PI)) + ((cosTheta * ((float) M_PI)) * (sqrtf((1.0f / ((float) M_PI))) + -1.0f)));
}
function code(cosTheta, c) return Float32(cosTheta * Float32(sqrt(Float32(pi)) + Float32(Float32(cosTheta * Float32(pi)) * Float32(sqrt(Float32(Float32(1.0) / Float32(pi))) + Float32(-1.0))))) end
function tmp = code(cosTheta, c) tmp = cosTheta * (sqrt(single(pi)) + ((cosTheta * single(pi)) * (sqrt((single(1.0) / single(pi))) + single(-1.0)))); end
\begin{array}{l}
\\
cosTheta \cdot \left(\sqrt{\pi} + \left(cosTheta \cdot \pi\right) \cdot \left(\sqrt{\frac{1}{\pi}} + -1\right)\right)
\end{array}
Initial program 98.0%
associate-+l+98.0%
+-commutative98.0%
fma-define98.0%
Simplified98.6%
Taylor expanded in cosTheta around 0 96.3%
mul-1-neg96.3%
unsub-neg96.3%
associate-*r*96.3%
associate-+r+96.3%
mul-1-neg96.3%
unsub-neg96.3%
Simplified96.3%
Taylor expanded in c around 0 96.3%
Final simplification96.3%
(FPCore (cosTheta c) :precision binary32 (/ 1.0 (- 1.0 (- (* (sqrt (/ (+ 1.0 (* cosTheta -2.0)) PI)) (/ -1.0 cosTheta)) c))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f - ((sqrtf(((1.0f + (cosTheta * -2.0f)) / ((float) M_PI))) * (-1.0f / cosTheta)) - c));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) - Float32(Float32(sqrt(Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(-2.0))) / Float32(pi))) * Float32(Float32(-1.0) / cosTheta)) - c))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) - ((sqrt(((single(1.0) + (cosTheta * single(-2.0))) / single(pi))) * (single(-1.0) / cosTheta)) - c)); end
\begin{array}{l}
\\
\frac{1}{1 - \left(\sqrt{\frac{1 + cosTheta \cdot -2}{\pi}} \cdot \frac{-1}{cosTheta} - c\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
+-commutative98.0%
fma-define98.0%
Simplified98.6%
associate-/l/98.6%
clear-num98.6%
inv-pow98.6%
+-commutative98.6%
fma-define98.6%
Applied egg-rr98.6%
*-un-lft-identity98.6%
unpow-198.6%
associate-/r/98.5%
pow-exp98.6%
distribute-lft-neg-out98.6%
unpow298.6%
Applied egg-rr98.6%
*-lft-identity98.6%
fma-define98.6%
+-commutative98.6%
associate-*l/98.5%
neg-mul-198.5%
*-lft-identity98.5%
neg-mul-198.5%
associate-*l/98.6%
*-commutative98.6%
Simplified98.6%
Taylor expanded in c around 0 98.2%
Taylor expanded in cosTheta around 0 96.0%
Final simplification96.0%
(FPCore (cosTheta c) :precision binary32 (/ 1.0 (+ 1.0 (- c (* (sqrt (/ 1.0 PI)) (- (/ -1.0 cosTheta) -1.0))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c - (sqrtf((1.0f / ((float) M_PI))) * ((-1.0f / cosTheta) - -1.0f))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c - Float32(sqrt(Float32(Float32(1.0) / Float32(pi))) * Float32(Float32(Float32(-1.0) / cosTheta) - Float32(-1.0)))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c - (sqrt((single(1.0) / single(pi))) * ((single(-1.0) / cosTheta) - single(-1.0))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c - \sqrt{\frac{1}{\pi}} \cdot \left(\frac{-1}{cosTheta} - -1\right)\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
+-commutative98.0%
fma-define98.0%
Simplified98.6%
Taylor expanded in cosTheta around 0 95.7%
mul-1-neg95.7%
Simplified95.7%
Taylor expanded in cosTheta around inf 95.8%
associate--l+95.8%
sub-neg95.8%
mul-1-neg95.8%
+-commutative95.8%
distribute-rgt-out95.8%
Simplified95.8%
Final simplification95.8%
(FPCore (cosTheta c) :precision binary32 (/ 1.0 (+ 1.0 (* (sqrt (/ 1.0 PI)) (+ (/ 1.0 cosTheta) -1.0)))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (sqrtf((1.0f / ((float) M_PI))) * ((1.0f / cosTheta) + -1.0f)));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(sqrt(Float32(Float32(1.0) / Float32(pi))) * Float32(Float32(Float32(1.0) / cosTheta) + Float32(-1.0))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (sqrt((single(1.0) / single(pi))) * ((single(1.0) / cosTheta) + single(-1.0)))); end
\begin{array}{l}
\\
\frac{1}{1 + \sqrt{\frac{1}{\pi}} \cdot \left(\frac{1}{cosTheta} + -1\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
+-commutative98.0%
fma-define98.0%
Simplified98.6%
Taylor expanded in cosTheta around 0 95.7%
mul-1-neg95.7%
Simplified95.7%
Taylor expanded in c around 0 95.7%
associate--l+95.7%
sub-neg95.7%
mul-1-neg95.7%
+-commutative95.7%
distribute-rgt-out95.7%
Simplified95.7%
Final simplification95.7%
(FPCore (cosTheta c) :precision binary32 (* cosTheta (sqrt PI)))
float code(float cosTheta, float c) {
return cosTheta * sqrtf(((float) M_PI));
}
function code(cosTheta, c) return Float32(cosTheta * sqrt(Float32(pi))) end
function tmp = code(cosTheta, c) tmp = cosTheta * sqrt(single(pi)); end
\begin{array}{l}
\\
cosTheta \cdot \sqrt{\pi}
\end{array}
Initial program 98.0%
associate-+l+98.0%
+-commutative98.0%
fma-define98.0%
Simplified98.6%
associate-/l/98.6%
clear-num98.6%
inv-pow98.6%
+-commutative98.6%
fma-define98.6%
Applied egg-rr98.6%
Taylor expanded in cosTheta around 0 93.3%
(FPCore (cosTheta c) :precision binary32 (- 1.0 c))
float code(float cosTheta, float c) {
return 1.0f - c;
}
real(4) function code(costheta, c)
real(4), intent (in) :: costheta
real(4), intent (in) :: c
code = 1.0e0 - c
end function
function code(cosTheta, c) return Float32(Float32(1.0) - c) end
function tmp = code(cosTheta, c) tmp = single(1.0) - c; end
\begin{array}{l}
\\
1 - c
\end{array}
Initial program 98.0%
associate-+l+98.0%
+-commutative98.0%
fma-define98.0%
Simplified98.6%
Taylor expanded in c around inf 10.7%
Taylor expanded in c around 0 10.7%
mul-1-neg10.7%
unsub-neg10.7%
Simplified10.7%
(FPCore (cosTheta c) :precision binary32 1.0)
float code(float cosTheta, float c) {
return 1.0f;
}
real(4) function code(costheta, c)
real(4), intent (in) :: costheta
real(4), intent (in) :: c
code = 1.0e0
end function
function code(cosTheta, c) return Float32(1.0) end
function tmp = code(cosTheta, c) tmp = single(1.0); end
\begin{array}{l}
\\
1
\end{array}
Initial program 98.0%
associate-+l+98.0%
+-commutative98.0%
fma-define98.0%
Simplified98.6%
Taylor expanded in c around inf 10.7%
Taylor expanded in c around 0 10.7%
herbie shell --seed 2024150
(FPCore (cosTheta c)
:name "Beckmann Sample, normalization factor"
:precision binary32
:pre (and (and (< 0.0 cosTheta) (< cosTheta 0.9999)) (and (< -1.0 c) (< c 1.0)))
(/ 1.0 (+ (+ 1.0 c) (* (* (/ 1.0 (sqrt PI)) (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta)) (exp (* (- cosTheta) cosTheta))))))