
(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 7 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 (* 0.5 (pow E (/ (fma cosTheta_O cosTheta_i (fma v (- 0.6931 (log v)) -1.0)) v))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return 0.5f * powf(((float) M_E), (fmaf(cosTheta_O, cosTheta_i, fmaf(v, (0.6931f - logf(v)), -1.0f)) / v));
}
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(0.5) * (Float32(exp(1)) ^ Float32(fma(cosTheta_O, cosTheta_i, fma(v, Float32(Float32(0.6931) - log(v)), Float32(-1.0))) / v))) end
\begin{array}{l}
\\
0.5 \cdot {e}^{\left(\frac{\mathsf{fma}\left(cosTheta\_O, cosTheta\_i, \mathsf{fma}\left(v, 0.6931 - \log v, -1\right)\right)}{v}\right)}
\end{array}
Initial program 99.4%
exp-sum99.3%
*-commutative99.3%
rem-exp-log99.3%
associate-/r*99.3%
metadata-eval99.3%
associate--l-99.3%
associate-/l*99.3%
associate-/l*99.3%
fma-define99.3%
Simplified99.3%
Taylor expanded in sinTheta_i around 0 99.7%
add-exp-log99.7%
log-div99.7%
add-log-exp99.8%
+-commutative99.8%
associate-/l*99.8%
fma-define99.8%
Applied egg-rr99.8%
Taylor expanded in v around 0 99.8%
*-un-lft-identity99.8%
exp-prod99.8%
associate--l+99.8%
fma-define99.8%
fma-neg99.8%
metadata-eval99.8%
Applied egg-rr99.8%
Final simplification99.8%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 (* 0.5 (exp (/ (+ -1.0 (* v (- 0.6931 (log v)))) v))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return 0.5f * expf(((-1.0f + (v * (0.6931f - logf(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((((-1.0e0) + (v * (0.6931e0 - log(v)))) / v))
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(0.5) * exp(Float32(Float32(Float32(-1.0) + Float32(v * Float32(Float32(0.6931) - log(v)))) / v))) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = single(0.5) * exp(((single(-1.0) + (v * (single(0.6931) - log(v)))) / v)); end
\begin{array}{l}
\\
0.5 \cdot e^{\frac{-1 + v \cdot \left(0.6931 - \log v\right)}{v}}
\end{array}
Initial program 99.4%
exp-sum99.3%
*-commutative99.3%
rem-exp-log99.3%
associate-/r*99.3%
metadata-eval99.3%
associate--l-99.3%
associate-/l*99.3%
associate-/l*99.3%
fma-define99.3%
Simplified99.3%
Taylor expanded in sinTheta_i around 0 99.7%
add-exp-log99.7%
log-div99.7%
add-log-exp99.8%
+-commutative99.8%
associate-/l*99.8%
fma-define99.8%
Applied egg-rr99.8%
Taylor expanded in v 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)) (log 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)) - logf(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)) - log(v)))
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(0.5) * exp(Float32(Float32(Float32(0.6931) + Float32(Float32(-1.0) / v)) - log(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)) - log(v))); end
\begin{array}{l}
\\
0.5 \cdot e^{\left(0.6931 + \frac{-1}{v}\right) - \log v}
\end{array}
Initial program 99.4%
exp-sum99.3%
*-commutative99.3%
rem-exp-log99.3%
associate-/r*99.3%
metadata-eval99.3%
associate--l-99.3%
associate-/l*99.3%
associate-/l*99.3%
fma-define99.3%
Simplified99.3%
Taylor expanded in sinTheta_i around 0 99.7%
add-exp-log99.7%
log-div99.7%
add-log-exp99.8%
+-commutative99.8%
associate-/l*99.8%
fma-define99.8%
Applied egg-rr99.8%
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%
exp-sum99.3%
*-commutative99.3%
rem-exp-log99.3%
associate-/r*99.3%
metadata-eval99.3%
associate--l-99.3%
associate-/l*99.3%
associate-/l*99.3%
fma-define99.3%
Simplified99.3%
Taylor expanded in sinTheta_i around 0 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 (* (/ 0.5 v) (exp (/ -1.0 v))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return (0.5f / v) * 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 = (0.5e0 / v) * exp(((-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(-1.0) / v))) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = (single(0.5) / v) * exp((single(-1.0) / v)); end
\begin{array}{l}
\\
\frac{0.5}{v} \cdot e^{\frac{-1}{v}}
\end{array}
Initial program 99.4%
exp-sum99.3%
*-commutative99.3%
rem-exp-log99.3%
associate-/r*99.3%
metadata-eval99.3%
associate--l-99.3%
associate-/l*99.3%
associate-/l*99.3%
fma-define99.3%
Simplified99.3%
Taylor expanded in sinTheta_i around 0 99.3%
Taylor expanded in cosTheta_O around 0 99.3%
Taylor expanded in v around 0 97.7%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 (* 0.5 (exp (* cosTheta_O (/ cosTheta_i v)))))
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return 0.5f * expf((cosTheta_O * (cosTheta_i / 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((costheta_o * (costheta_i / v)))
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(Float32(0.5) * exp(Float32(cosTheta_O * Float32(cosTheta_i / v)))) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = single(0.5) * exp((cosTheta_O * (cosTheta_i / v))); end
\begin{array}{l}
\\
0.5 \cdot e^{cosTheta\_O \cdot \frac{cosTheta\_i}{v}}
\end{array}
Initial program 99.4%
exp-sum99.3%
*-commutative99.3%
rem-exp-log99.3%
associate-/r*99.3%
metadata-eval99.3%
associate--l-99.3%
associate-/l*99.3%
associate-/l*99.3%
fma-define99.3%
Simplified99.3%
Taylor expanded in sinTheta_i around 0 99.7%
add-exp-log99.7%
log-div99.7%
add-log-exp99.8%
+-commutative99.8%
associate-/l*99.8%
fma-define99.8%
Applied egg-rr99.8%
Taylor expanded in cosTheta_O around inf 12.0%
associate-*r/12.0%
Simplified12.0%
(FPCore (cosTheta_i cosTheta_O sinTheta_i sinTheta_O v) :precision binary32 0.5)
float code(float cosTheta_i, float cosTheta_O, float sinTheta_i, float sinTheta_O, float v) {
return 0.5f;
}
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
end function
function code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) return Float32(0.5) end
function tmp = code(cosTheta_i, cosTheta_O, sinTheta_i, sinTheta_O, v) tmp = single(0.5); end
\begin{array}{l}
\\
0.5
\end{array}
Initial program 99.4%
exp-sum99.3%
*-commutative99.3%
rem-exp-log99.3%
associate-/r*99.3%
metadata-eval99.3%
associate--l-99.3%
associate-/l*99.3%
associate-/l*99.3%
fma-define99.3%
Simplified99.3%
Taylor expanded in sinTheta_i around 0 99.7%
add-exp-log99.7%
log-div99.7%
add-log-exp99.8%
+-commutative99.8%
associate-/l*99.8%
fma-define99.8%
Applied egg-rr99.8%
Taylor expanded in cosTheta_O around inf 12.0%
associate-*r/12.0%
Simplified12.0%
Taylor expanded in cosTheta_O around 0 6.5%
herbie shell --seed 2024144
(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))))))