
(FPCore (u0 u1 alphax alphay)
:precision binary32
(let* ((t_0
(atan (* (/ alphay alphax) (tan (+ (* (* 2.0 PI) u1) (* 0.5 PI))))))
(t_1 (sin t_0))
(t_2 (cos t_0)))
(/
1.0
(sqrt
(+
1.0
(/
(*
(/
1.0
(+
(/ (* t_2 t_2) (* alphax alphax))
(/ (* t_1 t_1) (* alphay alphay))))
u0)
(- 1.0 u0)))))))
float code(float u0, float u1, float alphax, float alphay) {
float t_0 = atanf(((alphay / alphax) * tanf((((2.0f * ((float) M_PI)) * u1) + (0.5f * ((float) M_PI))))));
float t_1 = sinf(t_0);
float t_2 = cosf(t_0);
return 1.0f / sqrtf((1.0f + (((1.0f / (((t_2 * t_2) / (alphax * alphax)) + ((t_1 * t_1) / (alphay * alphay)))) * u0) / (1.0f - u0))));
}
function code(u0, u1, alphax, alphay) t_0 = atan(Float32(Float32(alphay / alphax) * tan(Float32(Float32(Float32(Float32(2.0) * Float32(pi)) * u1) + Float32(Float32(0.5) * Float32(pi)))))) t_1 = sin(t_0) t_2 = cos(t_0) return Float32(Float32(1.0) / sqrt(Float32(Float32(1.0) + Float32(Float32(Float32(Float32(1.0) / Float32(Float32(Float32(t_2 * t_2) / Float32(alphax * alphax)) + Float32(Float32(t_1 * t_1) / Float32(alphay * alphay)))) * u0) / Float32(Float32(1.0) - u0))))) end
function tmp = code(u0, u1, alphax, alphay) t_0 = atan(((alphay / alphax) * tan((((single(2.0) * single(pi)) * u1) + (single(0.5) * single(pi)))))); t_1 = sin(t_0); t_2 = cos(t_0); tmp = single(1.0) / sqrt((single(1.0) + (((single(1.0) / (((t_2 * t_2) / (alphax * alphax)) + ((t_1 * t_1) / (alphay * alphay)))) * u0) / (single(1.0) - u0)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \tan^{-1} \left(\frac{alphay}{alphax} \cdot \tan \left(\left(2 \cdot \pi\right) \cdot u1 + 0.5 \cdot \pi\right)\right)\\
t_1 := \sin t\_0\\
t_2 := \cos t\_0\\
\frac{1}{\sqrt{1 + \frac{\frac{1}{\frac{t\_2 \cdot t\_2}{alphax \cdot alphax} + \frac{t\_1 \cdot t\_1}{alphay \cdot alphay}} \cdot u0}{1 - u0}}}
\end{array}
\end{array}
Herbie found 9 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (u0 u1 alphax alphay)
:precision binary32
(let* ((t_0
(atan (* (/ alphay alphax) (tan (+ (* (* 2.0 PI) u1) (* 0.5 PI))))))
(t_1 (sin t_0))
(t_2 (cos t_0)))
(/
1.0
(sqrt
(+
1.0
(/
(*
(/
1.0
(+
(/ (* t_2 t_2) (* alphax alphax))
(/ (* t_1 t_1) (* alphay alphay))))
u0)
(- 1.0 u0)))))))
float code(float u0, float u1, float alphax, float alphay) {
float t_0 = atanf(((alphay / alphax) * tanf((((2.0f * ((float) M_PI)) * u1) + (0.5f * ((float) M_PI))))));
float t_1 = sinf(t_0);
float t_2 = cosf(t_0);
return 1.0f / sqrtf((1.0f + (((1.0f / (((t_2 * t_2) / (alphax * alphax)) + ((t_1 * t_1) / (alphay * alphay)))) * u0) / (1.0f - u0))));
}
function code(u0, u1, alphax, alphay) t_0 = atan(Float32(Float32(alphay / alphax) * tan(Float32(Float32(Float32(Float32(2.0) * Float32(pi)) * u1) + Float32(Float32(0.5) * Float32(pi)))))) t_1 = sin(t_0) t_2 = cos(t_0) return Float32(Float32(1.0) / sqrt(Float32(Float32(1.0) + Float32(Float32(Float32(Float32(1.0) / Float32(Float32(Float32(t_2 * t_2) / Float32(alphax * alphax)) + Float32(Float32(t_1 * t_1) / Float32(alphay * alphay)))) * u0) / Float32(Float32(1.0) - u0))))) end
function tmp = code(u0, u1, alphax, alphay) t_0 = atan(((alphay / alphax) * tan((((single(2.0) * single(pi)) * u1) + (single(0.5) * single(pi)))))); t_1 = sin(t_0); t_2 = cos(t_0); tmp = single(1.0) / sqrt((single(1.0) + (((single(1.0) / (((t_2 * t_2) / (alphax * alphax)) + ((t_1 * t_1) / (alphay * alphay)))) * u0) / (single(1.0) - u0)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \tan^{-1} \left(\frac{alphay}{alphax} \cdot \tan \left(\left(2 \cdot \pi\right) \cdot u1 + 0.5 \cdot \pi\right)\right)\\
t_1 := \sin t\_0\\
t_2 := \cos t\_0\\
\frac{1}{\sqrt{1 + \frac{\frac{1}{\frac{t\_2 \cdot t\_2}{alphax \cdot alphax} + \frac{t\_1 \cdot t\_1}{alphay \cdot alphay}} \cdot u0}{1 - u0}}}
\end{array}
\end{array}
(FPCore (u0 u1 alphax alphay)
:precision binary32
(let* ((t_0
(atan (* (tan (fma (* PI 2.0) u1 (* PI 0.5))) (/ alphay alphax)))))
(sqrt
(/
1.0
(+
(/
(/
u0
(+
(/ (pow (sin t_0) 2.0) (* alphay alphay))
(/ (pow (cos t_0) 2.0) (* alphax alphax))))
(- 1.0 u0))
1.0)))))
float code(float u0, float u1, float alphax, float alphay) {
float t_0 = atanf((tanf(fmaf((((float) M_PI) * 2.0f), u1, (((float) M_PI) * 0.5f))) * (alphay / alphax)));
return sqrtf((1.0f / (((u0 / ((powf(sinf(t_0), 2.0f) / (alphay * alphay)) + (powf(cosf(t_0), 2.0f) / (alphax * alphax)))) / (1.0f - u0)) + 1.0f)));
}
function code(u0, u1, alphax, alphay) t_0 = atan(Float32(tan(fma(Float32(Float32(pi) * Float32(2.0)), u1, Float32(Float32(pi) * Float32(0.5)))) * Float32(alphay / alphax))) return sqrt(Float32(Float32(1.0) / Float32(Float32(Float32(u0 / Float32(Float32((sin(t_0) ^ Float32(2.0)) / Float32(alphay * alphay)) + Float32((cos(t_0) ^ Float32(2.0)) / Float32(alphax * alphax)))) / Float32(Float32(1.0) - u0)) + Float32(1.0)))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \tan^{-1} \left(\tan \left(\mathsf{fma}\left(\pi \cdot 2, u1, \pi \cdot 0.5\right)\right) \cdot \frac{alphay}{alphax}\right)\\
\sqrt{\frac{1}{\frac{\frac{u0}{\frac{{\sin t\_0}^{2}}{alphay \cdot alphay} + \frac{{\cos t\_0}^{2}}{alphax \cdot alphax}}}{1 - u0} + 1}}
\end{array}
\end{array}
Initial program 99.4%
Taylor expanded in u1 around 0
Applied rewrites99.9%
(FPCore (u0 u1 alphax alphay)
:precision binary32
(sqrt
(/
1.0
(+
(/
(/
u0
(+
(/
(pow (sin (atan (* (tan (* 0.5 PI)) (/ alphay alphax)))) 2.0)
(* alphay alphay))
(/
(pow
(cos
(atan (* (tan (fma (* PI 2.0) u1 (* PI 0.5))) (/ alphay alphax))))
2.0)
(* alphax alphax))))
(- 1.0 u0))
1.0))))
float code(float u0, float u1, float alphax, float alphay) {
return sqrtf((1.0f / (((u0 / ((powf(sinf(atanf((tanf((0.5f * ((float) M_PI))) * (alphay / alphax)))), 2.0f) / (alphay * alphay)) + (powf(cosf(atanf((tanf(fmaf((((float) M_PI) * 2.0f), u1, (((float) M_PI) * 0.5f))) * (alphay / alphax)))), 2.0f) / (alphax * alphax)))) / (1.0f - u0)) + 1.0f)));
}
function code(u0, u1, alphax, alphay) return sqrt(Float32(Float32(1.0) / Float32(Float32(Float32(u0 / Float32(Float32((sin(atan(Float32(tan(Float32(Float32(0.5) * Float32(pi))) * Float32(alphay / alphax)))) ^ Float32(2.0)) / Float32(alphay * alphay)) + Float32((cos(atan(Float32(tan(fma(Float32(Float32(pi) * Float32(2.0)), u1, Float32(Float32(pi) * Float32(0.5)))) * Float32(alphay / alphax)))) ^ Float32(2.0)) / Float32(alphax * alphax)))) / Float32(Float32(1.0) - u0)) + Float32(1.0)))) end
\begin{array}{l}
\\
\sqrt{\frac{1}{\frac{\frac{u0}{\frac{{\sin \tan^{-1} \left(\tan \left(0.5 \cdot \pi\right) \cdot \frac{alphay}{alphax}\right)}^{2}}{alphay \cdot alphay} + \frac{{\cos \tan^{-1} \left(\tan \left(\mathsf{fma}\left(\pi \cdot 2, u1, \pi \cdot 0.5\right)\right) \cdot \frac{alphay}{alphax}\right)}^{2}}{alphax \cdot alphax}}}{1 - u0} + 1}}
\end{array}
Initial program 99.4%
Taylor expanded in u1 around 0
Applied rewrites99.9%
Taylor expanded in u1 around 0
lower-*.f32N/A
lift-PI.f3298.7
Applied rewrites98.7%
(FPCore (u0 u1 alphax alphay)
:precision binary32
(sqrt
(/
1.0
(fma
(/
(* alphay alphay)
(pow
(sin (atan (* (tan (fma (* PI 2.0) u1 (* PI 0.5))) (/ alphay alphax))))
2.0))
(/ u0 (- 1.0 u0))
1.0))))
float code(float u0, float u1, float alphax, float alphay) {
return sqrtf((1.0f / fmaf(((alphay * alphay) / powf(sinf(atanf((tanf(fmaf((((float) M_PI) * 2.0f), u1, (((float) M_PI) * 0.5f))) * (alphay / alphax)))), 2.0f)), (u0 / (1.0f - u0)), 1.0f)));
}
function code(u0, u1, alphax, alphay) return sqrt(Float32(Float32(1.0) / fma(Float32(Float32(alphay * alphay) / (sin(atan(Float32(tan(fma(Float32(Float32(pi) * Float32(2.0)), u1, Float32(Float32(pi) * Float32(0.5)))) * Float32(alphay / alphax)))) ^ Float32(2.0))), Float32(u0 / Float32(Float32(1.0) - u0)), Float32(1.0)))) end
\begin{array}{l}
\\
\sqrt{\frac{1}{\mathsf{fma}\left(\frac{alphay \cdot alphay}{{\sin \tan^{-1} \left(\tan \left(\mathsf{fma}\left(\pi \cdot 2, u1, \pi \cdot 0.5\right)\right) \cdot \frac{alphay}{alphax}\right)}^{2}}, \frac{u0}{1 - u0}, 1\right)}}
\end{array}
Initial program 99.4%
Taylor expanded in alphax around inf
Applied rewrites98.1%
(FPCore (u0 u1 alphax alphay)
:precision binary32
(sqrt
(/
1.0
(fma
(/
(* alphay alphay)
(pow (sin (atan (* (tan (* 0.5 PI)) (/ alphay alphax)))) 2.0))
(/ u0 (- 1.0 u0))
1.0))))
float code(float u0, float u1, float alphax, float alphay) {
return sqrtf((1.0f / fmaf(((alphay * alphay) / powf(sinf(atanf((tanf((0.5f * ((float) M_PI))) * (alphay / alphax)))), 2.0f)), (u0 / (1.0f - u0)), 1.0f)));
}
function code(u0, u1, alphax, alphay) return sqrt(Float32(Float32(1.0) / fma(Float32(Float32(alphay * alphay) / (sin(atan(Float32(tan(Float32(Float32(0.5) * Float32(pi))) * Float32(alphay / alphax)))) ^ Float32(2.0))), Float32(u0 / Float32(Float32(1.0) - u0)), Float32(1.0)))) end
\begin{array}{l}
\\
\sqrt{\frac{1}{\mathsf{fma}\left(\frac{alphay \cdot alphay}{{\sin \tan^{-1} \left(\tan \left(0.5 \cdot \pi\right) \cdot \frac{alphay}{alphax}\right)}^{2}}, \frac{u0}{1 - u0}, 1\right)}}
\end{array}
Initial program 99.4%
Taylor expanded in alphax around inf
Applied rewrites98.1%
Taylor expanded in u1 around 0
lift-*.f32N/A
lift-PI.f3298.0
Applied rewrites98.0%
(FPCore (u0 u1 alphax alphay)
:precision binary32
(fma
(/
(* (* alphay alphay) u0)
(*
(pow (sin (atan (* (tan (* 0.5 PI)) (/ alphay alphax)))) 2.0)
(- 1.0 u0)))
-0.5
1.0))
float code(float u0, float u1, float alphax, float alphay) {
return fmaf((((alphay * alphay) * u0) / (powf(sinf(atanf((tanf((0.5f * ((float) M_PI))) * (alphay / alphax)))), 2.0f) * (1.0f - u0))), -0.5f, 1.0f);
}
function code(u0, u1, alphax, alphay) return fma(Float32(Float32(Float32(alphay * alphay) * u0) / Float32((sin(atan(Float32(tan(Float32(Float32(0.5) * Float32(pi))) * Float32(alphay / alphax)))) ^ Float32(2.0)) * Float32(Float32(1.0) - u0))), Float32(-0.5), Float32(1.0)) end
\begin{array}{l}
\\
\mathsf{fma}\left(\frac{\left(alphay \cdot alphay\right) \cdot u0}{{\sin \tan^{-1} \left(\tan \left(0.5 \cdot \pi\right) \cdot \frac{alphay}{alphax}\right)}^{2} \cdot \left(1 - u0\right)}, -0.5, 1\right)
\end{array}
Initial program 99.4%
Taylor expanded in alphay around 0
Applied rewrites96.6%
Taylor expanded in u1 around 0
lower-*.f32N/A
lift-PI.f3296.5
Applied rewrites96.5%
lift-*.f32N/A
lift-*.f32N/A
lift-/.f32N/A
pow2N/A
lift--.f32N/A
lift-/.f32N/A
frac-timesN/A
lower-/.f32N/A
Applied rewrites96.5%
(FPCore (u0 u1 alphax alphay)
:precision binary32
(fma
(*
(/
(* alphay alphay)
(pow (sin (atan (* (tan (* 0.5 PI)) (/ alphay alphax)))) 2.0))
(/ u0 (- 1.0 u0)))
-0.5
1.0))
float code(float u0, float u1, float alphax, float alphay) {
return fmaf((((alphay * alphay) / powf(sinf(atanf((tanf((0.5f * ((float) M_PI))) * (alphay / alphax)))), 2.0f)) * (u0 / (1.0f - u0))), -0.5f, 1.0f);
}
function code(u0, u1, alphax, alphay) return fma(Float32(Float32(Float32(alphay * alphay) / (sin(atan(Float32(tan(Float32(Float32(0.5) * Float32(pi))) * Float32(alphay / alphax)))) ^ Float32(2.0))) * Float32(u0 / Float32(Float32(1.0) - u0))), Float32(-0.5), Float32(1.0)) end
\begin{array}{l}
\\
\mathsf{fma}\left(\frac{alphay \cdot alphay}{{\sin \tan^{-1} \left(\tan \left(0.5 \cdot \pi\right) \cdot \frac{alphay}{alphax}\right)}^{2}} \cdot \frac{u0}{1 - u0}, -0.5, 1\right)
\end{array}
Initial program 99.4%
Taylor expanded in alphay around 0
Applied rewrites96.6%
Taylor expanded in u1 around 0
lower-*.f32N/A
lift-PI.f3296.5
Applied rewrites96.5%
(FPCore (u0 u1 alphax alphay)
:precision binary32
(fma
(*
(/
(* alphay alphay)
(pow (sin (atan (* (tan (* 0.5 PI)) (/ alphay alphax)))) 2.0))
(* u0 (+ 1.0 u0)))
-0.5
1.0))
float code(float u0, float u1, float alphax, float alphay) {
return fmaf((((alphay * alphay) / powf(sinf(atanf((tanf((0.5f * ((float) M_PI))) * (alphay / alphax)))), 2.0f)) * (u0 * (1.0f + u0))), -0.5f, 1.0f);
}
function code(u0, u1, alphax, alphay) return fma(Float32(Float32(Float32(alphay * alphay) / (sin(atan(Float32(tan(Float32(Float32(0.5) * Float32(pi))) * Float32(alphay / alphax)))) ^ Float32(2.0))) * Float32(u0 * Float32(Float32(1.0) + u0))), Float32(-0.5), Float32(1.0)) end
\begin{array}{l}
\\
\mathsf{fma}\left(\frac{alphay \cdot alphay}{{\sin \tan^{-1} \left(\tan \left(0.5 \cdot \pi\right) \cdot \frac{alphay}{alphax}\right)}^{2}} \cdot \left(u0 \cdot \left(1 + u0\right)\right), -0.5, 1\right)
\end{array}
Initial program 99.4%
Taylor expanded in alphay around 0
Applied rewrites96.6%
Taylor expanded in u1 around 0
lower-*.f32N/A
lift-PI.f3296.5
Applied rewrites96.5%
Taylor expanded in u0 around 0
lower-*.f32N/A
lower-+.f3295.8
Applied rewrites95.8%
(FPCore (u0 u1 alphax alphay)
:precision binary32
(fma
(*
(/
(* alphay alphay)
(pow (sin (atan (* (tan (* 0.5 PI)) (/ alphay alphax)))) 2.0))
u0)
-0.5
1.0))
float code(float u0, float u1, float alphax, float alphay) {
return fmaf((((alphay * alphay) / powf(sinf(atanf((tanf((0.5f * ((float) M_PI))) * (alphay / alphax)))), 2.0f)) * u0), -0.5f, 1.0f);
}
function code(u0, u1, alphax, alphay) return fma(Float32(Float32(Float32(alphay * alphay) / (sin(atan(Float32(tan(Float32(Float32(0.5) * Float32(pi))) * Float32(alphay / alphax)))) ^ Float32(2.0))) * u0), Float32(-0.5), Float32(1.0)) end
\begin{array}{l}
\\
\mathsf{fma}\left(\frac{alphay \cdot alphay}{{\sin \tan^{-1} \left(\tan \left(0.5 \cdot \pi\right) \cdot \frac{alphay}{alphax}\right)}^{2}} \cdot u0, -0.5, 1\right)
\end{array}
Initial program 99.4%
Taylor expanded in alphay around 0
Applied rewrites96.6%
Taylor expanded in u1 around 0
lower-*.f32N/A
lift-PI.f3296.5
Applied rewrites96.5%
Taylor expanded in u0 around 0
Applied rewrites95.1%
(FPCore (u0 u1 alphax alphay) :precision binary32 1.0)
float code(float u0, float u1, float alphax, float alphay) {
return 1.0f;
}
module fmin_fmax_functions
implicit none
private
public fmax
public fmin
interface fmax
module procedure fmax88
module procedure fmax44
module procedure fmax84
module procedure fmax48
end interface
interface fmin
module procedure fmin88
module procedure fmin44
module procedure fmin84
module procedure fmin48
end interface
contains
real(8) function fmax88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(4) function fmax44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, max(x, y), y /= y), x /= x)
end function
real(8) function fmax84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmax48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
end function
real(8) function fmin88(x, y) result (res)
real(8), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(4) function fmin44(x, y) result (res)
real(4), intent (in) :: x
real(4), intent (in) :: y
res = merge(y, merge(x, min(x, y), y /= y), x /= x)
end function
real(8) function fmin84(x, y) result(res)
real(8), intent (in) :: x
real(4), intent (in) :: y
res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
end function
real(8) function fmin48(x, y) result(res)
real(4), intent (in) :: x
real(8), intent (in) :: y
res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
end function
end module
real(4) function code(u0, u1, alphax, alphay)
use fmin_fmax_functions
real(4), intent (in) :: u0
real(4), intent (in) :: u1
real(4), intent (in) :: alphax
real(4), intent (in) :: alphay
code = 1.0e0
end function
function code(u0, u1, alphax, alphay) return Float32(1.0) end
function tmp = code(u0, u1, alphax, alphay) tmp = single(1.0); end
\begin{array}{l}
\\
1
\end{array}
Initial program 99.4%
Taylor expanded in u0 around 0
Applied rewrites91.6%
herbie shell --seed 2025101
(FPCore (u0 u1 alphax alphay)
:name "Trowbridge-Reitz Sample, sample surface normal, cosTheta"
:precision binary32
:pre (and (and (and (and (<= 2.328306437e-10 u0) (<= u0 1.0)) (and (<= 2.328306437e-10 u1) (<= u1 0.5))) (and (<= 0.0001 alphax) (<= alphax 1.0))) (and (<= 0.0001 alphay) (<= alphay 1.0)))
(/ 1.0 (sqrt (+ 1.0 (/ (* (/ 1.0 (+ (/ (* (cos (atan (* (/ alphay alphax) (tan (+ (* (* 2.0 PI) u1) (* 0.5 PI)))))) (cos (atan (* (/ alphay alphax) (tan (+ (* (* 2.0 PI) u1) (* 0.5 PI))))))) (* alphax alphax)) (/ (* (sin (atan (* (/ alphay alphax) (tan (+ (* (* 2.0 PI) u1) (* 0.5 PI)))))) (sin (atan (* (/ alphay alphax) (tan (+ (* (* 2.0 PI) u1) (* 0.5 PI))))))) (* alphay alphay)))) u0) (- 1.0 u0))))))