
(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 14 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
(+
1.0
(+
c
(/
(cbrt (pow (fma cosTheta -2.0 1.0) 1.5))
(* (sqrt PI) (* cosTheta (exp (* cosTheta cosTheta)))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + (cbrtf(powf(fmaf(cosTheta, -2.0f, 1.0f), 1.5f)) / (sqrtf(((float) M_PI)) * (cosTheta * expf((cosTheta * cosTheta)))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(cbrt((fma(cosTheta, Float32(-2.0), Float32(1.0)) ^ Float32(1.5))) / Float32(sqrt(Float32(pi)) * Float32(cosTheta * exp(Float32(cosTheta * cosTheta)))))))) end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{\sqrt[3]{{\left(\mathsf{fma}\left(cosTheta, -2, 1\right)\right)}^{1.5}}}{\sqrt{\pi} \cdot \left(cosTheta \cdot e^{cosTheta \cdot cosTheta}\right)}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*97.9%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.5%
associate-/l/98.6%
Simplified98.6%
add-cbrt-cube98.6%
add-sqr-sqrt98.5%
Applied egg-rr98.5%
*-commutative98.5%
unpow1/298.5%
pow-plus98.6%
metadata-eval98.6%
Simplified98.6%
Final simplification98.6%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(/
(sqrt (fma cosTheta -2.0 1.0))
(* (sqrt PI) (* cosTheta (exp (* cosTheta cosTheta)))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + (sqrtf(fmaf(cosTheta, -2.0f, 1.0f)) / (sqrtf(((float) M_PI)) * (cosTheta * expf((cosTheta * cosTheta)))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(sqrt(fma(cosTheta, Float32(-2.0), Float32(1.0))) / Float32(sqrt(Float32(pi)) * Float32(cosTheta * exp(Float32(cosTheta * cosTheta)))))))) end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{\sqrt{\mathsf{fma}\left(cosTheta, -2, 1\right)}}{\sqrt{\pi} \cdot \left(cosTheta \cdot e^{cosTheta \cdot cosTheta}\right)}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*97.9%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.5%
associate-/l/98.6%
Simplified98.6%
Final simplification98.6%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(*
(sqrt (/ (+ 1.0 (* cosTheta -2.0)) PI))
(/ 1.0 (* cosTheta (exp (pow cosTheta 2.0))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (sqrtf(((1.0f + (cosTheta * -2.0f)) / ((float) M_PI))) * (1.0f / (cosTheta * expf(powf(cosTheta, 2.0f))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(sqrt(Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(-2.0))) / Float32(pi))) * Float32(Float32(1.0) / Float32(cosTheta * exp((cosTheta ^ Float32(2.0)))))))) 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 * exp((cosTheta ^ single(2.0))))))); end
\begin{array}{l}
\\
\frac{1}{1 + \sqrt{\frac{1 + cosTheta \cdot -2}{\pi}} \cdot \frac{1}{cosTheta \cdot e^{{cosTheta}^{2}}}}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*97.9%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.5%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in c around 0 98.0%
Final simplification98.0%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(*
(/ (exp (- (pow cosTheta 2.0))) cosTheta)
(sqrt (/ (- 1.0 (* cosTheta 2.0)) PI))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + ((expf(-powf(cosTheta, 2.0f)) / cosTheta) * sqrtf(((1.0f - (cosTheta * 2.0f)) / ((float) M_PI)))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(Float32(exp(Float32(-(cosTheta ^ Float32(2.0)))) / 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) + ((exp(-(cosTheta ^ single(2.0))) / cosTheta) * sqrt(((single(1.0) - (cosTheta * single(2.0))) / single(pi))))); end
\begin{array}{l}
\\
\frac{1}{1 + \frac{e^{-{cosTheta}^{2}}}{cosTheta} \cdot \sqrt{\frac{1 - cosTheta \cdot 2}{\pi}}}
\end{array}
Initial program 98.0%
Taylor expanded in c around 0 98.0%
Final simplification98.0%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(/
(sqrt (/ (fma cosTheta -2.0 1.0) PI))
(* cosTheta (exp (* cosTheta cosTheta)))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (sqrtf((fmaf(cosTheta, -2.0f, 1.0f) / ((float) M_PI))) / (cosTheta * expf((cosTheta * cosTheta)))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(sqrt(Float32(fma(cosTheta, Float32(-2.0), Float32(1.0)) / Float32(pi))) / Float32(cosTheta * exp(Float32(cosTheta * cosTheta)))))) end
\begin{array}{l}
\\
\frac{1}{1 + \frac{\sqrt{\frac{\mathsf{fma}\left(cosTheta, -2, 1\right)}{\pi}}}{cosTheta \cdot e^{cosTheta \cdot cosTheta}}}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*97.9%
associate-*l/98.4%
*-lft-identity98.4%
associate-/l*98.5%
/-rgt-identity98.5%
associate-/l*98.5%
Simplified98.5%
add-sqr-sqrt97.8%
Applied egg-rr97.8%
Taylor expanded in c around 0 98.0%
+-commutative98.0%
associate-*r/97.9%
+-commutative97.9%
*-commutative97.9%
fma-udef97.9%
*-rgt-identity97.9%
*-commutative97.9%
unpow297.9%
Simplified97.9%
Final simplification97.9%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(/
(+ (- 1.0 cosTheta) (* (* cosTheta cosTheta) -0.5))
(* (sqrt PI) (+ cosTheta (pow cosTheta 3.0))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + (((1.0f - cosTheta) + ((cosTheta * cosTheta) * -0.5f)) / (sqrtf(((float) M_PI)) * (cosTheta + powf(cosTheta, 3.0f))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(Float32(Float32(1.0) - cosTheta) + Float32(Float32(cosTheta * cosTheta) * Float32(-0.5))) / Float32(sqrt(Float32(pi)) * Float32(cosTheta + (cosTheta ^ Float32(3.0)))))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c + (((single(1.0) - cosTheta) + ((cosTheta * cosTheta) * single(-0.5))) / (sqrt(single(pi)) * (cosTheta + (cosTheta ^ single(3.0))))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{\left(1 - cosTheta\right) + \left(cosTheta \cdot cosTheta\right) \cdot -0.5}{\sqrt{\pi} \cdot \left(cosTheta + {cosTheta}^{3}\right)}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*97.9%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.5%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in cosTheta around 0 97.0%
neg-mul-197.0%
associate-+r+97.0%
sub-neg97.0%
*-commutative97.0%
unpow297.0%
Simplified97.0%
Taylor expanded in cosTheta around 0 97.0%
Final simplification97.0%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(/
(+ -1.0 (+ (* cosTheta -0.5) (/ 1.0 cosTheta)))
(* (sqrt PI) (exp (* cosTheta cosTheta))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + ((-1.0f + ((cosTheta * -0.5f) + (1.0f / cosTheta))) / (sqrtf(((float) M_PI)) * expf((cosTheta * cosTheta))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(Float32(-1.0) + Float32(Float32(cosTheta * Float32(-0.5)) + Float32(Float32(1.0) / cosTheta))) / Float32(sqrt(Float32(pi)) * exp(Float32(cosTheta * cosTheta))))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c + ((single(-1.0) + ((cosTheta * single(-0.5)) + (single(1.0) / cosTheta))) / (sqrt(single(pi)) * exp((cosTheta * cosTheta)))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{-1 + \left(cosTheta \cdot -0.5 + \frac{1}{cosTheta}\right)}{\sqrt{\pi} \cdot e^{cosTheta \cdot cosTheta}}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*97.9%
associate-*l/98.4%
*-lft-identity98.4%
associate-/l*98.5%
/-rgt-identity98.5%
associate-/l*98.5%
Simplified98.5%
Taylor expanded in cosTheta around 0 96.9%
Final simplification96.9%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(/
(+ -1.0 (+ (* cosTheta -0.5) (/ 1.0 cosTheta)))
(* (sqrt PI) (+ 1.0 (* cosTheta cosTheta))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + ((-1.0f + ((cosTheta * -0.5f) + (1.0f / cosTheta))) / (sqrtf(((float) M_PI)) * (1.0f + (cosTheta * cosTheta))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(Float32(-1.0) + Float32(Float32(cosTheta * Float32(-0.5)) + Float32(Float32(1.0) / cosTheta))) / Float32(sqrt(Float32(pi)) * Float32(Float32(1.0) + Float32(cosTheta * cosTheta))))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c + ((single(-1.0) + ((cosTheta * single(-0.5)) + (single(1.0) / cosTheta))) / (sqrt(single(pi)) * (single(1.0) + (cosTheta * cosTheta)))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{-1 + \left(cosTheta \cdot -0.5 + \frac{1}{cosTheta}\right)}{\sqrt{\pi} \cdot \left(1 + cosTheta \cdot cosTheta\right)}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*97.9%
associate-*l/98.4%
*-lft-identity98.4%
associate-/l*98.5%
/-rgt-identity98.5%
associate-/l*98.5%
Simplified98.5%
Taylor expanded in cosTheta around 0 96.9%
Taylor expanded in cosTheta around 0 97.0%
distribute-rgt1-in96.9%
unpow296.9%
Simplified96.9%
Final simplification96.9%
(FPCore (cosTheta c) :precision binary32 (/ 1.0 (+ 1.0 (* (sqrt (/ 1.0 PI)) (+ -1.0 (+ (/ 1.0 cosTheta) (* cosTheta -1.5)))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (sqrtf((1.0f / ((float) M_PI))) * (-1.0f + ((1.0f / cosTheta) + (cosTheta * -1.5f)))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(sqrt(Float32(Float32(1.0) / Float32(pi))) * Float32(Float32(-1.0) + Float32(Float32(Float32(1.0) / cosTheta) + Float32(cosTheta * Float32(-1.5))))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (sqrt((single(1.0) / single(pi))) * (single(-1.0) + ((single(1.0) / cosTheta) + (cosTheta * single(-1.5)))))); end
\begin{array}{l}
\\
\frac{1}{1 + \sqrt{\frac{1}{\pi}} \cdot \left(-1 + \left(\frac{1}{cosTheta} + cosTheta \cdot -1.5\right)\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*97.9%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.5%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in cosTheta around 0 97.0%
neg-mul-197.0%
associate-+r+97.0%
sub-neg97.0%
*-commutative97.0%
unpow297.0%
Simplified97.0%
Taylor expanded in c around 0 96.4%
*-commutative96.4%
*-commutative96.4%
unpow296.4%
associate-*r*96.4%
*-commutative96.4%
unpow296.4%
Simplified96.4%
Taylor expanded in cosTheta around 0 96.4%
Final simplification96.4%
(FPCore (cosTheta c) :precision binary32 (/ 1.0 (+ c (+ 1.0 (/ (+ -1.0 (/ 1.0 cosTheta)) (sqrt PI))))))
float code(float cosTheta, float c) {
return 1.0f / (c + (1.0f + ((-1.0f + (1.0f / cosTheta)) / sqrtf(((float) M_PI)))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(c + Float32(Float32(1.0) + Float32(Float32(Float32(-1.0) + Float32(Float32(1.0) / cosTheta)) / sqrt(Float32(pi)))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (c + (single(1.0) + ((single(-1.0) + (single(1.0) / cosTheta)) / sqrt(single(pi))))); end
\begin{array}{l}
\\
\frac{1}{c + \left(1 + \frac{-1 + \frac{1}{cosTheta}}{\sqrt{\pi}}\right)}
\end{array}
Initial program 98.0%
+-commutative98.0%
fma-def98.0%
Simplified98.4%
Taylor expanded in cosTheta around 0 95.5%
+-commutative95.5%
distribute-rgt-out95.5%
fma-def95.5%
Simplified95.5%
fma-udef95.5%
sqrt-div95.5%
metadata-eval95.5%
inv-pow95.5%
Applied egg-rr95.5%
+-commutative95.5%
associate-*l/95.9%
*-lft-identity95.9%
unpow-195.9%
Simplified95.9%
Final simplification95.9%
(FPCore (cosTheta c) :precision binary32 (/ 1.0 (+ 1.0 (/ (+ -1.0 (/ 1.0 cosTheta)) (sqrt PI)))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + ((-1.0f + (1.0f / cosTheta)) / sqrtf(((float) M_PI))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(Float32(Float32(-1.0) + Float32(Float32(1.0) / cosTheta)) / sqrt(Float32(pi))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + ((single(-1.0) + (single(1.0) / cosTheta)) / sqrt(single(pi)))); end
\begin{array}{l}
\\
\frac{1}{1 + \frac{-1 + \frac{1}{cosTheta}}{\sqrt{\pi}}}
\end{array}
Initial program 98.0%
+-commutative98.0%
fma-def98.0%
Simplified98.4%
Taylor expanded in cosTheta around 0 95.5%
+-commutative95.5%
distribute-rgt-out95.5%
fma-def95.5%
Simplified95.5%
Taylor expanded in c around 0 95.4%
pow195.4%
sub-neg95.4%
metadata-eval95.4%
sqrt-div95.4%
metadata-eval95.4%
Applied egg-rr95.4%
unpow195.4%
associate-*r/95.8%
*-rgt-identity95.8%
+-commutative95.8%
Simplified95.8%
Final simplification95.8%
(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%
associate-*l*97.9%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.5%
associate-/l/98.6%
Simplified98.6%
add-cbrt-cube98.6%
add-sqr-sqrt98.5%
Applied egg-rr98.5%
*-commutative98.5%
unpow1/298.5%
pow-plus98.6%
metadata-eval98.6%
Simplified98.6%
Taylor expanded in cosTheta around 0 93.2%
Final simplification93.2%
(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%
associate-*l*97.9%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.5%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in cosTheta around inf 10.8%
Taylor expanded in c around 0 10.8%
+-commutative10.8%
mul-1-neg10.8%
unsub-neg10.8%
Simplified10.8%
Final simplification10.8%
(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%
associate-*l*97.9%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.5%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in c around 0 98.0%
Taylor expanded in cosTheta around inf 10.8%
Final simplification10.8%
herbie shell --seed 2023309
(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))))))