
(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 8 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
(let* ((t_0 (+ 0.6931 (/ (fma cosTheta_O cosTheta_i -1.0) v))))
(/
1.0
(/
(*
(pow (cbrt v) 2.0)
(exp (* (- (log (* v 2.0)) t_0) 0.3333333333333333)))
(pow (cbrt (* 0.5 (exp t_0))) 2.0)))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
float t_0 = 0.6931f + (fmaf(cosTheta_O, cosTheta_i, -1.0f) / v);
return 1.0f / ((powf(cbrtf(v), 2.0f) * expf(((logf((v * 2.0f)) - t_0) * 0.3333333333333333f))) / powf(cbrtf((0.5f * expf(t_0))), 2.0f));
}
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) t_0 = Float32(Float32(0.6931) + Float32(fma(cosTheta_O, cosTheta_i, Float32(-1.0)) / v)) return Float32(Float32(1.0) / Float32(Float32((cbrt(v) ^ Float32(2.0)) * exp(Float32(Float32(log(Float32(v * Float32(2.0))) - t_0) * Float32(0.3333333333333333)))) / (cbrt(Float32(Float32(0.5) * exp(t_0))) ^ Float32(2.0)))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := 0.6931 + \frac{\mathsf{fma}\left(cosTheta\_O, cosTheta\_i, -1\right)}{v}\\
\frac{1}{\frac{{\left(\sqrt[3]{v}\right)}^{2} \cdot e^{\left(\log \left(v \cdot 2\right) - t\_0\right) \cdot 0.3333333333333333}}{{\left(\sqrt[3]{0.5 \cdot e^{t\_0}}\right)}^{2}}}
\end{array}
\end{array}
Initial program 99.4%
associate-+l+99.4%
associate--l-99.4%
associate-/l*99.4%
associate-/l*99.4%
associate-/r*99.4%
metadata-eval99.4%
Simplified99.4%
Applied egg-rr99.8%
Taylor expanded in sinTheta_i around 0 99.8%
add-cube-cbrt99.8%
add-cube-cbrt99.8%
times-frac99.8%
Applied egg-rr99.8%
associate-*l/99.8%
Simplified99.8%
pow1/399.8%
associate-*r/99.8%
*-commutative99.8%
metadata-eval99.8%
div-inv99.8%
add-exp-log99.8%
exp-sum99.8%
metadata-eval99.8%
fma-neg99.8%
prod-exp99.8%
exp-diff99.8%
pow-to-exp99.8%
Applied egg-rr99.8%
Final simplification99.8%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v)
:precision binary32
(/
1.0
(/
(*
(pow (cbrt v) 2.0)
(* (cbrt (/ v (exp (+ 0.6931 (/ -1.0 v))))) (cbrt 2.0)))
(pow
(cbrt (* 0.5 (exp (+ 0.6931 (/ (fma cosTheta_O cosTheta_i -1.0) v)))))
2.0))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return 1.0f / ((powf(cbrtf(v), 2.0f) * (cbrtf((v / expf((0.6931f + (-1.0f / v))))) * cbrtf(2.0f))) / powf(cbrtf((0.5f * expf((0.6931f + (fmaf(cosTheta_O, cosTheta_i, -1.0f) / v))))), 2.0f));
}
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(1.0) / Float32(Float32((cbrt(v) ^ Float32(2.0)) * Float32(cbrt(Float32(v / exp(Float32(Float32(0.6931) + Float32(Float32(-1.0) / v))))) * cbrt(Float32(2.0)))) / (cbrt(Float32(Float32(0.5) * exp(Float32(Float32(0.6931) + Float32(fma(cosTheta_O, cosTheta_i, Float32(-1.0)) / v))))) ^ Float32(2.0)))) end
\begin{array}{l}
\\
\frac{1}{\frac{{\left(\sqrt[3]{v}\right)}^{2} \cdot \left(\sqrt[3]{\frac{v}{e^{0.6931 + \frac{-1}{v}}}} \cdot \sqrt[3]{2}\right)}{{\left(\sqrt[3]{0.5 \cdot e^{0.6931 + \frac{\mathsf{fma}\left(cosTheta\_O, cosTheta\_i, -1\right)}{v}}}\right)}^{2}}}
\end{array}
Initial program 99.4%
associate-+l+99.4%
associate--l-99.4%
associate-/l*99.4%
associate-/l*99.4%
associate-/r*99.4%
metadata-eval99.4%
Simplified99.4%
Applied egg-rr99.8%
Taylor expanded in sinTheta_i around 0 99.8%
add-cube-cbrt99.8%
add-cube-cbrt99.8%
times-frac99.8%
Applied egg-rr99.8%
associate-*l/99.8%
Simplified99.8%
Taylor expanded in cosTheta_O around 0 99.8%
unpow1/399.8%
*-lft-identity99.8%
Simplified99.8%
Final simplification99.8%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v)
:precision binary32
(/
1.0
(/
(* (pow (cbrt v) 2.0) (cbrt (* 2.0 (/ v (exp (+ 0.6931 (/ -1.0 v)))))))
(pow
(cbrt (* 0.5 (exp (+ 0.6931 (/ (fma cosTheta_O cosTheta_i -1.0) v)))))
2.0))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return 1.0f / ((powf(cbrtf(v), 2.0f) * cbrtf((2.0f * (v / expf((0.6931f + (-1.0f / v))))))) / powf(cbrtf((0.5f * expf((0.6931f + (fmaf(cosTheta_O, cosTheta_i, -1.0f) / v))))), 2.0f));
}
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(1.0) / Float32(Float32((cbrt(v) ^ Float32(2.0)) * cbrt(Float32(Float32(2.0) * Float32(v / exp(Float32(Float32(0.6931) + Float32(Float32(-1.0) / v))))))) / (cbrt(Float32(Float32(0.5) * exp(Float32(Float32(0.6931) + Float32(fma(cosTheta_O, cosTheta_i, Float32(-1.0)) / v))))) ^ Float32(2.0)))) end
\begin{array}{l}
\\
\frac{1}{\frac{{\left(\sqrt[3]{v}\right)}^{2} \cdot \sqrt[3]{2 \cdot \frac{v}{e^{0.6931 + \frac{-1}{v}}}}}{{\left(\sqrt[3]{0.5 \cdot e^{0.6931 + \frac{\mathsf{fma}\left(cosTheta\_O, cosTheta\_i, -1\right)}{v}}}\right)}^{2}}}
\end{array}
Initial program 99.4%
associate-+l+99.4%
associate--l-99.4%
associate-/l*99.4%
associate-/l*99.4%
associate-/r*99.4%
metadata-eval99.4%
Simplified99.4%
Applied egg-rr99.8%
Taylor expanded in sinTheta_i around 0 99.8%
add-cube-cbrt99.8%
add-cube-cbrt99.8%
times-frac99.8%
Applied egg-rr99.8%
associate-*l/99.8%
Simplified99.8%
Taylor expanded in cosTheta_O around 0 99.8%
Final simplification99.8%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 (/ 1.0 (/ v (* 0.5 (exp (+ 0.6931 (/ -1.0 v)))))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return 1.0f / (v / (0.5f * 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 = 1.0e0 / (v / (0.5e0 * exp((0.6931e0 + ((-1.0e0) / v)))))
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(1.0) / Float32(v / Float32(Float32(0.5) * 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(1.0) / (v / (single(0.5) * exp((single(0.6931) + (single(-1.0) / v))))); end
\begin{array}{l}
\\
\frac{1}{\frac{v}{0.5 \cdot e^{0.6931 + \frac{-1}{v}}}}
\end{array}
Initial program 99.4%
associate-+l+99.4%
associate--l-99.4%
associate-/l*99.4%
associate-/l*99.4%
associate-/r*99.4%
metadata-eval99.4%
Simplified99.4%
Applied egg-rr99.8%
Taylor expanded in sinTheta_i around 0 99.8%
Taylor expanded in cosTheta_O around 0 99.8%
Final simplification99.8%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 (* 0.5 (/ (exp (+ 0.6931 (/ -1.0 v))) v)))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return 0.5f * (expf((0.6931f + (-1.0f / v))) / 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 * (exp((0.6931e0 + ((-1.0e0) / v))) / v)
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(0.5) * Float32(exp(Float32(Float32(0.6931) + Float32(Float32(-1.0) / v))) / v)) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = single(0.5) * (exp((single(0.6931) + (single(-1.0) / v))) / v); end
\begin{array}{l}
\\
0.5 \cdot \frac{e^{0.6931 + \frac{-1}{v}}}{v}
\end{array}
Initial program 99.4%
+-commutative99.4%
exp-sum99.4%
rem-exp-log99.4%
associate-/r*99.4%
metadata-eval99.4%
+-rgt-identity99.4%
metadata-eval99.4%
metadata-eval99.4%
+-rgt-identity99.4%
+-commutative99.4%
associate--l-99.4%
associate-+r-99.4%
Simplified99.4%
Taylor expanded in sinTheta_i around 0 99.8%
Taylor expanded in cosTheta_O around 0 99.8%
Final simplification99.8%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 (/ (* 0.5 (exp (+ 0.6931 (/ -1.0 v)))) v))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return (0.5f * expf((0.6931f + (-1.0f / v)))) / 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 * exp((0.6931e0 + ((-1.0e0) / v)))) / v
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(Float32(0.5) * exp(Float32(Float32(0.6931) + Float32(Float32(-1.0) / v)))) / v) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = (single(0.5) * exp((single(0.6931) + (single(-1.0) / v)))) / v; end
\begin{array}{l}
\\
\frac{0.5 \cdot e^{0.6931 + \frac{-1}{v}}}{v}
\end{array}
Initial program 99.4%
associate-+l+99.4%
associate--l-99.4%
associate-/l*99.4%
associate-/l*99.4%
associate-/r*99.4%
metadata-eval99.4%
Simplified99.4%
Taylor expanded in sinTheta_i around 0 99.4%
Taylor expanded in cosTheta_O around 0 99.4%
sub-neg99.4%
exp-sum99.4%
exp-sum99.4%
rem-exp-log99.4%
distribute-neg-frac99.4%
metadata-eval99.4%
Simplified99.4%
Taylor expanded in v around 0 99.8%
associate-*r/99.8%
prod-exp99.8%
Simplified99.8%
Final simplification99.8%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 (* 0.5 (/ (pow E (/ -1.0 v)) v)))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return 0.5f * (powf(((float) M_E), (-1.0f / v)) / v);
}
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(0.5) * Float32((Float32(exp(1)) ^ Float32(Float32(-1.0) / v)) / v)) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = single(0.5) * ((single(2.71828182845904523536) ^ (single(-1.0) / v)) / v); end
\begin{array}{l}
\\
0.5 \cdot \frac{{e}^{\left(\frac{-1}{v}\right)}}{v}
\end{array}
Initial program 99.4%
+-commutative99.4%
exp-sum99.4%
rem-exp-log99.4%
associate-/r*99.4%
metadata-eval99.4%
+-rgt-identity99.4%
metadata-eval99.4%
metadata-eval99.4%
+-rgt-identity99.4%
+-commutative99.4%
associate--l-99.4%
associate-+r-99.4%
Simplified99.4%
Taylor expanded in sinTheta_i around 0 99.8%
*-un-lft-identity99.8%
exp-prod99.7%
exp-1-e99.7%
+-commutative99.7%
associate-/l*99.7%
fma-define99.7%
Applied egg-rr99.7%
Taylor expanded in cosTheta_O around 0 99.7%
Taylor expanded in v around 0 98.3%
Final simplification98.3%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 (* 0.5 (/ (exp 0.6931) v)))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return 0.5f * (expf(0.6931f) / 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 * (exp(0.6931e0) / v)
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(0.5) * Float32(exp(Float32(0.6931)) / v)) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = single(0.5) * (exp(single(0.6931)) / v); end
\begin{array}{l}
\\
0.5 \cdot \frac{e^{0.6931}}{v}
\end{array}
Initial program 99.4%
+-commutative99.4%
exp-sum99.4%
rem-exp-log99.4%
associate-/r*99.4%
metadata-eval99.4%
+-rgt-identity99.4%
metadata-eval99.4%
metadata-eval99.4%
+-rgt-identity99.4%
+-commutative99.4%
associate--l-99.4%
associate-+r-99.4%
Simplified99.4%
Taylor expanded in v around inf 4.6%
Final simplification4.6%
herbie shell --seed 2024050
(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))))))