
(FPCore (u v) :precision binary32 (+ 1.0 (* v (log (+ u (* (- 1.0 u) (exp (/ -2.0 v))))))))
float code(float u, float v) {
return 1.0f + (v * logf((u + ((1.0f - u) * expf((-2.0f / v))))));
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
code = 1.0e0 + (v * log((u + ((1.0e0 - u) * exp(((-2.0e0) / v))))))
end function
function code(u, v) return Float32(Float32(1.0) + Float32(v * log(Float32(u + Float32(Float32(Float32(1.0) - u) * exp(Float32(Float32(-2.0) / v))))))) end
function tmp = code(u, v) tmp = single(1.0) + (v * log((u + ((single(1.0) - u) * exp((single(-2.0) / v)))))); end
\begin{array}{l}
\\
1 + v \cdot \log \left(u + \left(1 - u\right) \cdot e^{\frac{-2}{v}}\right)
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 11 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (u v) :precision binary32 (+ 1.0 (* v (log (+ u (* (- 1.0 u) (exp (/ -2.0 v))))))))
float code(float u, float v) {
return 1.0f + (v * logf((u + ((1.0f - u) * expf((-2.0f / v))))));
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
code = 1.0e0 + (v * log((u + ((1.0e0 - u) * exp(((-2.0e0) / v))))))
end function
function code(u, v) return Float32(Float32(1.0) + Float32(v * log(Float32(u + Float32(Float32(Float32(1.0) - u) * exp(Float32(Float32(-2.0) / v))))))) end
function tmp = code(u, v) tmp = single(1.0) + (v * log((u + ((single(1.0) - u) * exp((single(-2.0) / v)))))); end
\begin{array}{l}
\\
1 + v \cdot \log \left(u + \left(1 - u\right) \cdot e^{\frac{-2}{v}}\right)
\end{array}
(FPCore (u v) :precision binary32 (+ 1.0 (* v (* 2.0 (log (sqrt (+ u (* (exp (/ -2.0 v)) (- 1.0 u)))))))))
float code(float u, float v) {
return 1.0f + (v * (2.0f * logf(sqrtf((u + (expf((-2.0f / v)) * (1.0f - u)))))));
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
code = 1.0e0 + (v * (2.0e0 * log(sqrt((u + (exp(((-2.0e0) / v)) * (1.0e0 - u)))))))
end function
function code(u, v) return Float32(Float32(1.0) + Float32(v * Float32(Float32(2.0) * log(sqrt(Float32(u + Float32(exp(Float32(Float32(-2.0) / v)) * Float32(Float32(1.0) - u)))))))) end
function tmp = code(u, v) tmp = single(1.0) + (v * (single(2.0) * log(sqrt((u + (exp((single(-2.0) / v)) * (single(1.0) - u))))))); end
\begin{array}{l}
\\
1 + v \cdot \left(2 \cdot \log \left(\sqrt{u + e^{\frac{-2}{v}} \cdot \left(1 - u\right)}\right)\right)
\end{array}
Initial program 99.4%
add-sqr-sqrt99.4%
log-prod99.5%
+-commutative99.5%
fma-undefine99.5%
+-commutative99.5%
fma-undefine99.5%
Applied egg-rr99.5%
count-299.5%
Simplified99.5%
Taylor expanded in v around 0 99.5%
Final simplification99.5%
(FPCore (u v) :precision binary32 (+ 1.0 (* v (log (+ u (* (exp (/ -2.0 v)) (- 1.0 u)))))))
float code(float u, float v) {
return 1.0f + (v * logf((u + (expf((-2.0f / v)) * (1.0f - u)))));
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
code = 1.0e0 + (v * log((u + (exp(((-2.0e0) / v)) * (1.0e0 - u)))))
end function
function code(u, v) return Float32(Float32(1.0) + Float32(v * log(Float32(u + Float32(exp(Float32(Float32(-2.0) / v)) * Float32(Float32(1.0) - u)))))) end
function tmp = code(u, v) tmp = single(1.0) + (v * log((u + (exp((single(-2.0) / v)) * (single(1.0) - u))))); end
\begin{array}{l}
\\
1 + v \cdot \log \left(u + e^{\frac{-2}{v}} \cdot \left(1 - u\right)\right)
\end{array}
Initial program 99.4%
Final simplification99.4%
(FPCore (u v) :precision binary32 (if (<= v 0.10000000149011612) 1.0 (+ (* u (* v (+ (/ 1.0 (exp (/ -2.0 v))) -1.0))) -1.0)))
float code(float u, float v) {
float tmp;
if (v <= 0.10000000149011612f) {
tmp = 1.0f;
} else {
tmp = (u * (v * ((1.0f / expf((-2.0f / v))) + -1.0f))) + -1.0f;
}
return tmp;
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
real(4) :: tmp
if (v <= 0.10000000149011612e0) then
tmp = 1.0e0
else
tmp = (u * (v * ((1.0e0 / exp(((-2.0e0) / v))) + (-1.0e0)))) + (-1.0e0)
end if
code = tmp
end function
function code(u, v) tmp = Float32(0.0) if (v <= Float32(0.10000000149011612)) tmp = Float32(1.0); else tmp = Float32(Float32(u * Float32(v * Float32(Float32(Float32(1.0) / exp(Float32(Float32(-2.0) / v))) + Float32(-1.0)))) + Float32(-1.0)); end return tmp end
function tmp_2 = code(u, v) tmp = single(0.0); if (v <= single(0.10000000149011612)) tmp = single(1.0); else tmp = (u * (v * ((single(1.0) / exp((single(-2.0) / v))) + single(-1.0)))) + single(-1.0); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;v \leq 0.10000000149011612:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;u \cdot \left(v \cdot \left(\frac{1}{e^{\frac{-2}{v}}} + -1\right)\right) + -1\\
\end{array}
\end{array}
if v < 0.100000001Initial program 100.0%
add-sqr-sqrt100.0%
log-prod100.0%
+-commutative100.0%
fma-undefine100.0%
+-commutative100.0%
fma-undefine100.0%
Applied egg-rr100.0%
count-2100.0%
Simplified100.0%
Taylor expanded in v around 0 93.8%
if 0.100000001 < v Initial program 93.3%
Taylor expanded in u around 0 74.6%
Final simplification92.2%
(FPCore (u v) :precision binary32 (if (<= v 0.10000000149011612) 1.0 (+ -1.0 (* (* v u) (expm1 (/ 2.0 v))))))
float code(float u, float v) {
float tmp;
if (v <= 0.10000000149011612f) {
tmp = 1.0f;
} else {
tmp = -1.0f + ((v * u) * expm1f((2.0f / v)));
}
return tmp;
}
function code(u, v) tmp = Float32(0.0) if (v <= Float32(0.10000000149011612)) tmp = Float32(1.0); else tmp = Float32(Float32(-1.0) + Float32(Float32(v * u) * expm1(Float32(Float32(2.0) / v)))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;v \leq 0.10000000149011612:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1 + \left(v \cdot u\right) \cdot \mathsf{expm1}\left(\frac{2}{v}\right)\\
\end{array}
\end{array}
if v < 0.100000001Initial program 100.0%
add-sqr-sqrt100.0%
log-prod100.0%
+-commutative100.0%
fma-undefine100.0%
+-commutative100.0%
fma-undefine100.0%
Applied egg-rr100.0%
count-2100.0%
Simplified100.0%
Taylor expanded in v around 0 93.8%
if 0.100000001 < v Initial program 93.3%
*-un-lft-identity93.3%
exp-prod93.3%
Applied egg-rr93.3%
exp-1-e93.3%
Simplified93.3%
Taylor expanded in u around 0 72.9%
associate-+r+72.8%
log-E74.6%
metadata-eval74.6%
metadata-eval74.6%
associate-*r*74.6%
*-commutative74.6%
rec-exp74.6%
log-E74.6%
metadata-eval74.6%
log-E74.6%
associate-*r/74.6%
log-E74.6%
metadata-eval74.6%
metadata-eval74.6%
Simplified74.6%
Final simplification92.2%
(FPCore (u v) :precision binary32 (if (<= v 0.10000000149011612) 1.0 (* u (+ 2.0 (- (/ (+ 2.0 (/ 1.3333333333333333 v)) v) (/ 1.0 u))))))
float code(float u, float v) {
float tmp;
if (v <= 0.10000000149011612f) {
tmp = 1.0f;
} else {
tmp = u * (2.0f + (((2.0f + (1.3333333333333333f / v)) / v) - (1.0f / u)));
}
return tmp;
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
real(4) :: tmp
if (v <= 0.10000000149011612e0) then
tmp = 1.0e0
else
tmp = u * (2.0e0 + (((2.0e0 + (1.3333333333333333e0 / v)) / v) - (1.0e0 / u)))
end if
code = tmp
end function
function code(u, v) tmp = Float32(0.0) if (v <= Float32(0.10000000149011612)) tmp = Float32(1.0); else tmp = Float32(u * Float32(Float32(2.0) + Float32(Float32(Float32(Float32(2.0) + Float32(Float32(1.3333333333333333) / v)) / v) - Float32(Float32(1.0) / u)))); end return tmp end
function tmp_2 = code(u, v) tmp = single(0.0); if (v <= single(0.10000000149011612)) tmp = single(1.0); else tmp = u * (single(2.0) + (((single(2.0) + (single(1.3333333333333333) / v)) / v) - (single(1.0) / u))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;v \leq 0.10000000149011612:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;u \cdot \left(2 + \left(\frac{2 + \frac{1.3333333333333333}{v}}{v} - \frac{1}{u}\right)\right)\\
\end{array}
\end{array}
if v < 0.100000001Initial program 100.0%
add-sqr-sqrt100.0%
log-prod100.0%
+-commutative100.0%
fma-undefine100.0%
+-commutative100.0%
fma-undefine100.0%
Applied egg-rr100.0%
count-2100.0%
Simplified100.0%
Taylor expanded in v around 0 93.8%
if 0.100000001 < v Initial program 93.3%
Taylor expanded in u around 0 73.5%
Taylor expanded in v around -inf 69.3%
associate-+r+69.4%
mul-1-neg69.4%
unsub-neg69.4%
distribute-lft-in69.4%
metadata-eval69.4%
associate-+r+69.9%
metadata-eval69.9%
mul-1-neg69.9%
fma-define69.9%
Simplified69.9%
Taylor expanded in u around inf 69.3%
associate--r+69.3%
cancel-sign-sub-inv69.3%
metadata-eval69.3%
*-lft-identity69.3%
associate--l+69.3%
associate-*r/69.3%
metadata-eval69.3%
Simplified69.3%
Final simplification91.8%
(FPCore (u v) :precision binary32 (if (<= v 0.10000000149011612) 1.0 (- (- -1.0 (* u -2.0)) (/ (* u (+ -2.0 (/ -1.3333333333333333 v))) v))))
float code(float u, float v) {
float tmp;
if (v <= 0.10000000149011612f) {
tmp = 1.0f;
} else {
tmp = (-1.0f - (u * -2.0f)) - ((u * (-2.0f + (-1.3333333333333333f / v))) / v);
}
return tmp;
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
real(4) :: tmp
if (v <= 0.10000000149011612e0) then
tmp = 1.0e0
else
tmp = ((-1.0e0) - (u * (-2.0e0))) - ((u * ((-2.0e0) + ((-1.3333333333333333e0) / v))) / v)
end if
code = tmp
end function
function code(u, v) tmp = Float32(0.0) if (v <= Float32(0.10000000149011612)) tmp = Float32(1.0); else tmp = Float32(Float32(Float32(-1.0) - Float32(u * Float32(-2.0))) - Float32(Float32(u * Float32(Float32(-2.0) + Float32(Float32(-1.3333333333333333) / v))) / v)); end return tmp end
function tmp_2 = code(u, v) tmp = single(0.0); if (v <= single(0.10000000149011612)) tmp = single(1.0); else tmp = (single(-1.0) - (u * single(-2.0))) - ((u * (single(-2.0) + (single(-1.3333333333333333) / v))) / v); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;v \leq 0.10000000149011612:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;\left(-1 - u \cdot -2\right) - \frac{u \cdot \left(-2 + \frac{-1.3333333333333333}{v}\right)}{v}\\
\end{array}
\end{array}
if v < 0.100000001Initial program 100.0%
add-sqr-sqrt100.0%
log-prod100.0%
+-commutative100.0%
fma-undefine100.0%
+-commutative100.0%
fma-undefine100.0%
Applied egg-rr100.0%
count-2100.0%
Simplified100.0%
Taylor expanded in v around 0 93.8%
if 0.100000001 < v Initial program 93.3%
Taylor expanded in u around 0 73.5%
Taylor expanded in v around -inf 69.3%
associate-+r+69.4%
mul-1-neg69.4%
unsub-neg69.4%
distribute-lft-in69.4%
metadata-eval69.4%
associate-+r+69.9%
metadata-eval69.9%
mul-1-neg69.9%
fma-define69.9%
Simplified69.9%
Taylor expanded in u around 0 69.9%
mul-1-neg69.9%
distribute-rgt-neg-in69.9%
mul-1-neg69.9%
distribute-lft-in69.9%
metadata-eval69.9%
neg-mul-169.9%
distribute-lft-neg-in69.9%
metadata-eval69.9%
associate-*r/69.9%
metadata-eval69.9%
Simplified69.9%
Final simplification91.8%
(FPCore (u v) :precision binary32 (if (<= v 0.10000000149011612) 1.0 (+ 1.0 (+ -2.0 (* 2.0 (+ u (/ u v)))))))
float code(float u, float v) {
float tmp;
if (v <= 0.10000000149011612f) {
tmp = 1.0f;
} else {
tmp = 1.0f + (-2.0f + (2.0f * (u + (u / v))));
}
return tmp;
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
real(4) :: tmp
if (v <= 0.10000000149011612e0) then
tmp = 1.0e0
else
tmp = 1.0e0 + ((-2.0e0) + (2.0e0 * (u + (u / v))))
end if
code = tmp
end function
function code(u, v) tmp = Float32(0.0) if (v <= Float32(0.10000000149011612)) tmp = Float32(1.0); else tmp = Float32(Float32(1.0) + Float32(Float32(-2.0) + Float32(Float32(2.0) * Float32(u + Float32(u / v))))); end return tmp end
function tmp_2 = code(u, v) tmp = single(0.0); if (v <= single(0.10000000149011612)) tmp = single(1.0); else tmp = single(1.0) + (single(-2.0) + (single(2.0) * (u + (u / v)))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;v \leq 0.10000000149011612:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;1 + \left(-2 + 2 \cdot \left(u + \frac{u}{v}\right)\right)\\
\end{array}
\end{array}
if v < 0.100000001Initial program 100.0%
add-sqr-sqrt100.0%
log-prod100.0%
+-commutative100.0%
fma-undefine100.0%
+-commutative100.0%
fma-undefine100.0%
Applied egg-rr100.0%
count-2100.0%
Simplified100.0%
Taylor expanded in v around 0 93.8%
if 0.100000001 < v Initial program 93.3%
Taylor expanded in u around 0 73.5%
Taylor expanded in v around inf 65.9%
sub-neg65.9%
distribute-lft-out65.9%
metadata-eval65.9%
Simplified65.9%
Final simplification91.5%
(FPCore (u v) :precision binary32 (if (<= v 0.10000000149011612) 1.0 (+ -1.0 (* 2.0 (+ u (/ u v))))))
float code(float u, float v) {
float tmp;
if (v <= 0.10000000149011612f) {
tmp = 1.0f;
} else {
tmp = -1.0f + (2.0f * (u + (u / v)));
}
return tmp;
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
real(4) :: tmp
if (v <= 0.10000000149011612e0) then
tmp = 1.0e0
else
tmp = (-1.0e0) + (2.0e0 * (u + (u / v)))
end if
code = tmp
end function
function code(u, v) tmp = Float32(0.0) if (v <= Float32(0.10000000149011612)) tmp = Float32(1.0); else tmp = Float32(Float32(-1.0) + Float32(Float32(2.0) * Float32(u + Float32(u / v)))); end return tmp end
function tmp_2 = code(u, v) tmp = single(0.0); if (v <= single(0.10000000149011612)) tmp = single(1.0); else tmp = single(-1.0) + (single(2.0) * (u + (u / v))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;v \leq 0.10000000149011612:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1 + 2 \cdot \left(u + \frac{u}{v}\right)\\
\end{array}
\end{array}
if v < 0.100000001Initial program 100.0%
add-sqr-sqrt100.0%
log-prod100.0%
+-commutative100.0%
fma-undefine100.0%
+-commutative100.0%
fma-undefine100.0%
Applied egg-rr100.0%
count-2100.0%
Simplified100.0%
Taylor expanded in v around 0 93.8%
if 0.100000001 < v Initial program 93.3%
Taylor expanded in u around 0 73.5%
Taylor expanded in v around inf 65.7%
sub-neg65.7%
distribute-lft-out65.7%
metadata-eval65.7%
Simplified65.7%
Final simplification91.5%
(FPCore (u v) :precision binary32 (if (<= v 0.10000000149011612) 1.0 (+ -1.0 (* 2.0 u))))
float code(float u, float v) {
float tmp;
if (v <= 0.10000000149011612f) {
tmp = 1.0f;
} else {
tmp = -1.0f + (2.0f * u);
}
return tmp;
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
real(4) :: tmp
if (v <= 0.10000000149011612e0) then
tmp = 1.0e0
else
tmp = (-1.0e0) + (2.0e0 * u)
end if
code = tmp
end function
function code(u, v) tmp = Float32(0.0) if (v <= Float32(0.10000000149011612)) tmp = Float32(1.0); else tmp = Float32(Float32(-1.0) + Float32(Float32(2.0) * u)); end return tmp end
function tmp_2 = code(u, v) tmp = single(0.0); if (v <= single(0.10000000149011612)) tmp = single(1.0); else tmp = single(-1.0) + (single(2.0) * u); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;v \leq 0.10000000149011612:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1 + 2 \cdot u\\
\end{array}
\end{array}
if v < 0.100000001Initial program 100.0%
add-sqr-sqrt100.0%
log-prod100.0%
+-commutative100.0%
fma-undefine100.0%
+-commutative100.0%
fma-undefine100.0%
Applied egg-rr100.0%
count-2100.0%
Simplified100.0%
Taylor expanded in v around 0 93.8%
if 0.100000001 < v Initial program 93.3%
Taylor expanded in u around 0 73.5%
Taylor expanded in v around inf 56.9%
Final simplification90.8%
(FPCore (u v) :precision binary32 (if (<= v 0.10000000149011612) 1.0 -1.0))
float code(float u, float v) {
float tmp;
if (v <= 0.10000000149011612f) {
tmp = 1.0f;
} else {
tmp = -1.0f;
}
return tmp;
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
real(4) :: tmp
if (v <= 0.10000000149011612e0) then
tmp = 1.0e0
else
tmp = -1.0e0
end if
code = tmp
end function
function code(u, v) tmp = Float32(0.0) if (v <= Float32(0.10000000149011612)) tmp = Float32(1.0); else tmp = Float32(-1.0); end return tmp end
function tmp_2 = code(u, v) tmp = single(0.0); if (v <= single(0.10000000149011612)) tmp = single(1.0); else tmp = single(-1.0); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;v \leq 0.10000000149011612:\\
\;\;\;\;1\\
\mathbf{else}:\\
\;\;\;\;-1\\
\end{array}
\end{array}
if v < 0.100000001Initial program 100.0%
add-sqr-sqrt100.0%
log-prod100.0%
+-commutative100.0%
fma-undefine100.0%
+-commutative100.0%
fma-undefine100.0%
Applied egg-rr100.0%
count-2100.0%
Simplified100.0%
Taylor expanded in v around 0 93.8%
if 0.100000001 < v Initial program 93.3%
Taylor expanded in u around 0 46.7%
Final simplification89.9%
(FPCore (u v) :precision binary32 -1.0)
float code(float u, float v) {
return -1.0f;
}
real(4) function code(u, v)
real(4), intent (in) :: u
real(4), intent (in) :: v
code = -1.0e0
end function
function code(u, v) return Float32(-1.0) end
function tmp = code(u, v) tmp = single(-1.0); end
\begin{array}{l}
\\
-1
\end{array}
Initial program 99.4%
Taylor expanded in u around 0 6.7%
Final simplification6.7%
herbie shell --seed 2024080
(FPCore (u v)
:name "HairBSDF, sample_f, cosTheta"
:precision binary32
:pre (and (and (<= 1e-5 u) (<= u 1.0)) (and (<= 0.0 v) (<= v 109.746574)))
(+ 1.0 (* v (log (+ u (* (- 1.0 u) (exp (/ -2.0 v))))))))