
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v)
:precision binary32
(exp
(+
(+
(-
(- (/ (* cosTheta_i cosTheta_O) v) (/ (* sinTheta_i sinTheta_O) v))
(/ 1.0 v))
0.6931)
(log (/ 1.0 (* 2.0 v))))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return expf(((((((cosTheta_i * cosTheta_O) / v) - ((sinTheta_i * sinTheta_O) / v)) - (1.0f / v)) + 0.6931f) + logf((1.0f / (2.0f * v)))));
}
real(4) function code(costheta_i, costheta_o, sintheta_i, sintheta_o, v)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: costheta_o
real(4), intent (in) :: sintheta_i
real(4), intent (in) :: sintheta_o
real(4), intent (in) :: v
code = exp(((((((costheta_i * costheta_o) / v) - ((sintheta_i * sintheta_o) / v)) - (1.0e0 / v)) + 0.6931e0) + log((1.0e0 / (2.0e0 * v)))))
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return exp(Float32(Float32(Float32(Float32(Float32(Float32(cosTheta_i * cosTheta_O) / v) - Float32(Float32(sinTheta_i * sinTheta_O) / v)) - Float32(Float32(1.0) / v)) + Float32(0.6931)) + log(Float32(Float32(1.0) / Float32(Float32(2.0) * v))))) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = exp(((((((cosTheta_i * cosTheta_O) / v) - ((sinTheta_i * sinTheta_O) / v)) - (single(1.0) / v)) + single(0.6931)) + log((single(1.0) / (single(2.0) * v))))); end
\begin{array}{l}
\\
e^{\left(\left(\left(\frac{cosTheta\_i \cdot cosTheta\_O}{v} - \frac{sinTheta\_i \cdot sinTheta\_O}{v}\right) - \frac{1}{v}\right) + 0.6931\right) + \log \left(\frac{1}{2 \cdot v}\right)}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v)
:precision binary32
(exp
(+
(+
(-
(- (/ (* cosTheta_i cosTheta_O) v) (/ (* sinTheta_i sinTheta_O) v))
(/ 1.0 v))
0.6931)
(log (/ 1.0 (* 2.0 v))))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return expf(((((((cosTheta_i * cosTheta_O) / v) - ((sinTheta_i * sinTheta_O) / v)) - (1.0f / v)) + 0.6931f) + logf((1.0f / (2.0f * v)))));
}
real(4) function code(costheta_i, costheta_o, sintheta_i, sintheta_o, v)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: costheta_o
real(4), intent (in) :: sintheta_i
real(4), intent (in) :: sintheta_o
real(4), intent (in) :: v
code = exp(((((((costheta_i * costheta_o) / v) - ((sintheta_i * sintheta_o) / v)) - (1.0e0 / v)) + 0.6931e0) + log((1.0e0 / (2.0e0 * v)))))
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return exp(Float32(Float32(Float32(Float32(Float32(Float32(cosTheta_i * cosTheta_O) / v) - Float32(Float32(sinTheta_i * sinTheta_O) / v)) - Float32(Float32(1.0) / v)) + Float32(0.6931)) + log(Float32(Float32(1.0) / Float32(Float32(2.0) * v))))) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = exp(((((((cosTheta_i * cosTheta_O) / v) - ((sinTheta_i * sinTheta_O) / v)) - (single(1.0) / v)) + single(0.6931)) + log((single(1.0) / (single(2.0) * v))))); end
\begin{array}{l}
\\
e^{\left(\left(\left(\frac{cosTheta\_i \cdot cosTheta\_O}{v} - \frac{sinTheta\_i \cdot sinTheta\_O}{v}\right) - \frac{1}{v}\right) + 0.6931\right) + \log \left(\frac{1}{2 \cdot v}\right)}
\end{array}
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 (pow (sqrt E) (* 2.0 (+ (+ 0.6931 (log (/ 0.5 v))) (/ -1.0 v)))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return powf(sqrtf(((float) M_E)), (2.0f * ((0.6931f + logf((0.5f / v))) + (-1.0f / v))));
}
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return sqrt(Float32(exp(1))) ^ Float32(Float32(2.0) * Float32(Float32(Float32(0.6931) + log(Float32(Float32(0.5) / v))) + Float32(Float32(-1.0) / v))) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = sqrt(single(2.71828182845904523536)) ^ (single(2.0) * ((single(0.6931) + log((single(0.5) / v))) + (single(-1.0) / v))); end
\begin{array}{l}
\\
{\left(\sqrt{e}\right)}^{\left(2 \cdot \left(\left(0.6931 + \log \left(\frac{0.5}{v}\right)\right) + \frac{-1}{v}\right)\right)}
\end{array}
Initial program 99.7%
associate-+l+99.7%
associate--l-99.7%
associate-/l*99.7%
associate-/l*99.7%
associate-/r*99.7%
metadata-eval99.7%
Simplified99.7%
*-un-lft-identity99.7%
exp-prod99.7%
associate--r+99.7%
associate-*r/99.7%
associate-*r/99.7%
sub-div99.7%
Applied egg-rr99.7%
add-sqr-sqrt99.7%
unpow-prod-down99.8%
exp-1-e99.8%
sub-div99.8%
fmm-def99.8%
distribute-rgt-neg-out99.8%
exp-1-e99.8%
Applied egg-rr99.8%
pow-sqr99.7%
+-commutative99.7%
sub-neg99.7%
distribute-rgt-neg-in99.7%
fmm-def99.7%
*-commutative99.7%
*-commutative99.7%
metadata-eval99.7%
Simplified99.7%
Taylor expanded in cosTheta_O around inf 99.7%
Taylor expanded in cosTheta_O around 0 99.7%
Final simplification99.7%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v)
:precision binary32
(let* ((t_0
(pow
E
(/ (- (+ 0.6931 (/ -1.0 v)) (* sinTheta_O (/ sinTheta_i v))) 2.0))))
(* (/ 0.5 v) (* t_0 t_0))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
float t_0 = powf(((float) M_E), (((0.6931f + (-1.0f / v)) - (sinTheta_O * (sinTheta_i / v))) / 2.0f));
return (0.5f / v) * (t_0 * t_0);
}
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) t_0 = Float32(exp(1)) ^ Float32(Float32(Float32(Float32(0.6931) + Float32(Float32(-1.0) / v)) - Float32(sinTheta_O * Float32(sinTheta_i / v))) / Float32(2.0)) return Float32(Float32(Float32(0.5) / v) * Float32(t_0 * t_0)) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) t_0 = single(2.71828182845904523536) ^ (((single(0.6931) + (single(-1.0) / v)) - (sinTheta_O * (sinTheta_i / v))) / single(2.0)); tmp = (single(0.5) / v) * (t_0 * t_0); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := {e}^{\left(\frac{\left(0.6931 + \frac{-1}{v}\right) - sinTheta\_O \cdot \frac{sinTheta\_i}{v}}{2}\right)}\\
\frac{0.5}{v} \cdot \left(t\_0 \cdot t\_0\right)
\end{array}
\end{array}
Initial program 99.7%
exp-sum99.7%
*-commutative99.7%
rem-exp-log99.7%
associate-/r*99.7%
metadata-eval99.7%
associate--l-99.7%
associate-/l*99.7%
associate-/l*99.7%
fma-define99.7%
Simplified99.7%
*-un-lft-identity99.7%
exp-prod99.7%
fma-define99.7%
associate--r+99.7%
associate-*r/99.7%
associate-*r/99.7%
sub-div99.7%
Applied egg-rr99.7%
Taylor expanded in cosTheta_i around 0 99.7%
associate--r+99.7%
associate-/l*99.7%
Simplified99.7%
*-un-lft-identity99.7%
exp-prod99.7%
e-exp-199.7%
Applied egg-rr99.7%
sqr-pow99.7%
Applied egg-rr99.7%
Final simplification99.7%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 (* (/ 0.5 v) (pow E (+ 0.6931 (/ -1.0 v)))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return (0.5f / v) * powf(((float) M_E), (0.6931f + (-1.0f / v)));
}
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(Float32(0.5) / v) * (Float32(exp(1)) ^ Float32(Float32(0.6931) + Float32(Float32(-1.0) / v)))) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = (single(0.5) / v) * (single(2.71828182845904523536) ^ (single(0.6931) + (single(-1.0) / v))); end
\begin{array}{l}
\\
\frac{0.5}{v} \cdot {e}^{\left(0.6931 + \frac{-1}{v}\right)}
\end{array}
Initial program 99.7%
exp-sum99.7%
*-commutative99.7%
rem-exp-log99.7%
associate-/r*99.7%
metadata-eval99.7%
associate--l-99.7%
associate-/l*99.7%
associate-/l*99.7%
fma-define99.7%
Simplified99.7%
*-un-lft-identity99.7%
exp-prod99.7%
fma-define99.7%
associate--r+99.7%
associate-*r/99.7%
associate-*r/99.7%
sub-div99.7%
Applied egg-rr99.7%
Taylor expanded in cosTheta_i around 0 99.7%
associate--r+99.7%
associate-/l*99.7%
Simplified99.7%
*-un-lft-identity99.7%
exp-prod99.7%
e-exp-199.7%
Applied egg-rr99.7%
Taylor expanded in sinTheta_O around 0 99.5%
exp-to-pow99.7%
Simplified99.7%
Final simplification99.7%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 (* (/ 0.5 v) (exp (+ 0.6931 (/ -1.0 v)))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return (0.5f / v) * expf((0.6931f + (-1.0f / v)));
}
real(4) function code(costheta_i, costheta_o, sintheta_i, sintheta_o, v)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: costheta_o
real(4), intent (in) :: sintheta_i
real(4), intent (in) :: sintheta_o
real(4), intent (in) :: v
code = (0.5e0 / v) * exp((0.6931e0 + ((-1.0e0) / v)))
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(Float32(0.5) / v) * exp(Float32(Float32(0.6931) + Float32(Float32(-1.0) / v)))) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = (single(0.5) / v) * exp((single(0.6931) + (single(-1.0) / v))); end
\begin{array}{l}
\\
\frac{0.5}{v} \cdot e^{0.6931 + \frac{-1}{v}}
\end{array}
Initial program 99.7%
exp-sum99.7%
*-commutative99.7%
rem-exp-log99.7%
associate-/r*99.7%
metadata-eval99.7%
associate--l-99.7%
associate-/l*99.7%
associate-/l*99.7%
fma-define99.7%
Simplified99.7%
*-un-lft-identity99.7%
exp-prod99.7%
fma-define99.7%
associate--r+99.7%
associate-*r/99.7%
associate-*r/99.7%
sub-div99.7%
Applied egg-rr99.7%
Taylor expanded in cosTheta_i around 0 99.7%
associate--r+99.7%
associate-/l*99.7%
Simplified99.7%
Taylor expanded in sinTheta_O around 0 99.7%
Final simplification99.7%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 (exp (/ -1.0 v)))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return expf((-1.0f / v));
}
real(4) function code(costheta_i, costheta_o, sintheta_i, sintheta_o, v)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: costheta_o
real(4), intent (in) :: sintheta_i
real(4), intent (in) :: sintheta_o
real(4), intent (in) :: v
code = exp(((-1.0e0) / v))
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return exp(Float32(Float32(-1.0) / v)) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = exp((single(-1.0) / v)); end
\begin{array}{l}
\\
e^{\frac{-1}{v}}
\end{array}
Initial program 99.7%
associate-+l+99.7%
associate--l-99.7%
associate-/l*99.7%
associate-/l*99.7%
associate-/r*99.7%
metadata-eval99.7%
Simplified99.7%
Taylor expanded in sinTheta_i around 0 99.7%
Taylor expanded in v around 0 97.6%
Taylor expanded in cosTheta_O around 0 97.6%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 1.0)
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return 1.0f;
}
real(4) function code(costheta_i, costheta_o, sintheta_i, sintheta_o, v)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: costheta_o
real(4), intent (in) :: sintheta_i
real(4), intent (in) :: sintheta_o
real(4), intent (in) :: v
code = 1.0e0
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(1.0) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = single(1.0); end
\begin{array}{l}
\\
1
\end{array}
Initial program 99.7%
associate-+l+99.7%
associate--l-99.7%
associate-/l*99.7%
associate-/l*99.7%
associate-/r*99.7%
metadata-eval99.7%
Simplified99.7%
Taylor expanded in sinTheta_i around 0 99.7%
Taylor expanded in v around 0 97.6%
Taylor expanded in v around inf 6.5%
herbie shell --seed 2024151
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v)
:name "HairBSDF, Mp, lower"
:precision binary32
:pre (and (and (and (and (and (<= -1.0 cosTheta_i) (<= cosTheta_i 1.0)) (and (<= -1.0 cosTheta_O) (<= cosTheta_O 1.0))) (and (<= -1.0 sinTheta_i) (<= sinTheta_i 1.0))) (and (<= -1.0 sinTheta_O) (<= sinTheta_O 1.0))) (and (<= -1.5707964 v) (<= v 0.1)))
(exp (+ (+ (- (- (/ (* cosTheta_i cosTheta_O) v) (/ (* sinTheta_i sinTheta_O) v)) (/ 1.0 v)) 0.6931) (log (/ 1.0 (* 2.0 v))))))