
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log (- 1.0 u1)))) (cos (* (* 2.0 PI) u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-logf((1.0f - u1))) * cosf(((2.0f * ((float) M_PI)) * u2));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log(Float32(Float32(1.0) - u1)))) * cos(Float32(Float32(Float32(2.0) * Float32(pi)) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt(-log((single(1.0) - u1))) * cos(((single(2.0) * single(pi)) * u2)); end
\begin{array}{l}
\\
\sqrt{-\log \left(1 - u1\right)} \cdot \cos \left(\left(2 \cdot \pi\right) \cdot u2\right)
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 13 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log (- 1.0 u1)))) (cos (* (* 2.0 PI) u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-logf((1.0f - u1))) * cosf(((2.0f * ((float) M_PI)) * u2));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log(Float32(Float32(1.0) - u1)))) * cos(Float32(Float32(Float32(2.0) * Float32(pi)) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt(-log((single(1.0) - u1))) * cos(((single(2.0) * single(pi)) * u2)); end
\begin{array}{l}
\\
\sqrt{-\log \left(1 - u1\right)} \cdot \cos \left(\left(2 \cdot \pi\right) \cdot u2\right)
\end{array}
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (sin (* PI u2))))
(*
(sqrt (- (log1p (- u1))))
(+
(cos (* u2 (* 2.0 PI)))
(fma (- t_0) t_0 (* t_0 (sin (* u2 (+ (+ PI 1.0) -1.0)))))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = sinf((((float) M_PI) * u2));
return sqrtf(-log1pf(-u1)) * (cosf((u2 * (2.0f * ((float) M_PI)))) + fmaf(-t_0, t_0, (t_0 * sinf((u2 * ((((float) M_PI) + 1.0f) + -1.0f))))));
}
function code(cosTheta_i, u1, u2) t_0 = sin(Float32(Float32(pi) * u2)) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * Float32(cos(Float32(u2 * Float32(Float32(2.0) * Float32(pi)))) + fma(Float32(-t_0), t_0, Float32(t_0 * sin(Float32(u2 * Float32(Float32(Float32(pi) + Float32(1.0)) + Float32(-1.0)))))))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sin \left(\pi \cdot u2\right)\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \left(\cos \left(u2 \cdot \left(2 \cdot \pi\right)\right) + \mathsf{fma}\left(-t\_0, t\_0, t\_0 \cdot \sin \left(u2 \cdot \left(\left(\pi + 1\right) + -1\right)\right)\right)\right)
\end{array}
\end{array}
Initial program 58.4%
sub-neg58.4%
log1p-define99.1%
Simplified99.1%
associate-*l*99.1%
cos-298.9%
prod-diff98.9%
fma-neg98.9%
cos-299.1%
Applied egg-rr99.1%
associate-*r*99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
Simplified99.1%
expm1-log1p-u99.1%
Applied egg-rr99.1%
expm1-undefine99.1%
log1p-undefine99.1%
rem-exp-log99.1%
+-commutative99.1%
Applied egg-rr99.1%
Final simplification99.1%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (sin (* PI u2))))
(*
(sqrt (- (log1p (- u1))))
(+ (cos (* u2 (* 2.0 PI))) (fma (- t_0) t_0 (* t_0 t_0))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = sinf((((float) M_PI) * u2));
return sqrtf(-log1pf(-u1)) * (cosf((u2 * (2.0f * ((float) M_PI)))) + fmaf(-t_0, t_0, (t_0 * t_0)));
}
function code(cosTheta_i, u1, u2) t_0 = sin(Float32(Float32(pi) * u2)) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * Float32(cos(Float32(u2 * Float32(Float32(2.0) * Float32(pi)))) + fma(Float32(-t_0), t_0, Float32(t_0 * t_0)))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sin \left(\pi \cdot u2\right)\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \left(\cos \left(u2 \cdot \left(2 \cdot \pi\right)\right) + \mathsf{fma}\left(-t\_0, t\_0, t\_0 \cdot t\_0\right)\right)
\end{array}
\end{array}
Initial program 58.4%
sub-neg58.4%
log1p-define99.1%
Simplified99.1%
associate-*l*99.1%
cos-298.9%
prod-diff98.9%
fma-neg98.9%
cos-299.1%
Applied egg-rr99.1%
associate-*r*99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
Simplified99.1%
Final simplification99.1%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (sin (* PI u2))) (t_1 (cos (* u2 (* 2.0 PI)))))
(*
(sqrt (- (log1p (- u1))))
(+ t_1 (fma (- t_0) t_0 (- 0.5 (* t_1 0.5)))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = sinf((((float) M_PI) * u2));
float t_1 = cosf((u2 * (2.0f * ((float) M_PI))));
return sqrtf(-log1pf(-u1)) * (t_1 + fmaf(-t_0, t_0, (0.5f - (t_1 * 0.5f))));
}
function code(cosTheta_i, u1, u2) t_0 = sin(Float32(Float32(pi) * u2)) t_1 = cos(Float32(u2 * Float32(Float32(2.0) * Float32(pi)))) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * Float32(t_1 + fma(Float32(-t_0), t_0, Float32(Float32(0.5) - Float32(t_1 * Float32(0.5)))))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sin \left(\pi \cdot u2\right)\\
t_1 := \cos \left(u2 \cdot \left(2 \cdot \pi\right)\right)\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \left(t\_1 + \mathsf{fma}\left(-t\_0, t\_0, 0.5 - t\_1 \cdot 0.5\right)\right)
\end{array}
\end{array}
Initial program 58.4%
sub-neg58.4%
log1p-define99.1%
Simplified99.1%
associate-*l*99.1%
cos-298.9%
prod-diff98.9%
fma-neg98.9%
cos-299.1%
Applied egg-rr99.1%
associate-*r*99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
*-commutative99.1%
Simplified99.1%
expm1-log1p-u99.1%
Applied egg-rr99.1%
expm1-undefine99.1%
log1p-undefine99.1%
rem-exp-log99.1%
+-commutative99.1%
Applied egg-rr99.1%
add-sqr-sqrt99.1%
add-sqr-sqrt99.1%
associate--l+99.1%
metadata-eval99.1%
+-rgt-identity99.1%
add-sqr-sqrt99.1%
add-sqr-sqrt99.1%
*-commutative99.1%
*-commutative99.1%
sqr-sin-a99.1%
associate-*r*99.1%
*-commutative99.1%
*-commutative99.1%
Applied egg-rr99.1%
Final simplification99.1%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (cos (* u2 (* 2.0 PI)))))
(if (<= t_0 0.9999995827674866)
(*
t_0
(sqrt
(*
u1
(+ 1.0 (* u1 (+ 0.5 (* u1 (- 0.3333333333333333 (* u1 -0.25)))))))))
(sqrt (- (log1p (- u1)))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = cosf((u2 * (2.0f * ((float) M_PI))));
float tmp;
if (t_0 <= 0.9999995827674866f) {
tmp = t_0 * sqrtf((u1 * (1.0f + (u1 * (0.5f + (u1 * (0.3333333333333333f - (u1 * -0.25f))))))));
} else {
tmp = sqrtf(-log1pf(-u1));
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = cos(Float32(u2 * Float32(Float32(2.0) * Float32(pi)))) tmp = Float32(0.0) if (t_0 <= Float32(0.9999995827674866)) tmp = Float32(t_0 * sqrt(Float32(u1 * Float32(Float32(1.0) + Float32(u1 * Float32(Float32(0.5) + Float32(u1 * Float32(Float32(0.3333333333333333) - Float32(u1 * Float32(-0.25)))))))))); else tmp = sqrt(Float32(-log1p(Float32(-u1)))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \cos \left(u2 \cdot \left(2 \cdot \pi\right)\right)\\
\mathbf{if}\;t\_0 \leq 0.9999995827674866:\\
\;\;\;\;t\_0 \cdot \sqrt{u1 \cdot \left(1 + u1 \cdot \left(0.5 + u1 \cdot \left(0.3333333333333333 - u1 \cdot -0.25\right)\right)\right)}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)}\\
\end{array}
\end{array}
if (cos.f32 (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2)) < 0.999999583Initial program 56.7%
Taylor expanded in u1 around 0 93.1%
if 0.999999583 < (cos.f32 (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2)) Initial program 59.8%
sub-neg59.8%
log1p-define99.7%
Simplified99.7%
Taylor expanded in u2 around 0 99.6%
Final simplification96.6%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (cos (* u2 (* 2.0 PI)))))
(if (<= t_0 0.9999986886978149)
(* t_0 (sqrt (* u1 (- 1.0 (* u1 -0.5)))))
(sqrt (- (log1p (- u1)))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = cosf((u2 * (2.0f * ((float) M_PI))));
float tmp;
if (t_0 <= 0.9999986886978149f) {
tmp = t_0 * sqrtf((u1 * (1.0f - (u1 * -0.5f))));
} else {
tmp = sqrtf(-log1pf(-u1));
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = cos(Float32(u2 * Float32(Float32(2.0) * Float32(pi)))) tmp = Float32(0.0) if (t_0 <= Float32(0.9999986886978149)) tmp = Float32(t_0 * sqrt(Float32(u1 * Float32(Float32(1.0) - Float32(u1 * Float32(-0.5)))))); else tmp = sqrt(Float32(-log1p(Float32(-u1)))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \cos \left(u2 \cdot \left(2 \cdot \pi\right)\right)\\
\mathbf{if}\;t\_0 \leq 0.9999986886978149:\\
\;\;\;\;t\_0 \cdot \sqrt{u1 \cdot \left(1 - u1 \cdot -0.5\right)}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)}\\
\end{array}
\end{array}
if (cos.f32 (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2)) < 0.999998689Initial program 57.3%
Taylor expanded in u1 around 0 88.4%
if 0.999998689 < (cos.f32 (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2)) Initial program 59.1%
sub-neg59.1%
log1p-define99.6%
Simplified99.6%
Taylor expanded in u2 around 0 98.9%
Final simplification94.4%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log1p (- u1)))) (cos (* u2 (* 2.0 PI)))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-log1pf(-u1)) * cosf((u2 * (2.0f * ((float) M_PI))));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * cos(Float32(u2 * Float32(Float32(2.0) * Float32(pi))))) end
\begin{array}{l}
\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \cos \left(u2 \cdot \left(2 \cdot \pi\right)\right)
\end{array}
Initial program 58.4%
sub-neg58.4%
log1p-define99.1%
Simplified99.1%
Final simplification99.1%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (* u2 (* 2.0 PI))))
(if (<= t_0 0.0013650000328198075)
(sqrt (- (log1p (- u1))))
(*
(cos t_0)
(sqrt (* u1 (+ 1.0 (* u1 (- 0.5 (* u1 -0.3333333333333333))))))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = u2 * (2.0f * ((float) M_PI));
float tmp;
if (t_0 <= 0.0013650000328198075f) {
tmp = sqrtf(-log1pf(-u1));
} else {
tmp = cosf(t_0) * sqrtf((u1 * (1.0f + (u1 * (0.5f - (u1 * -0.3333333333333333f))))));
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = Float32(u2 * Float32(Float32(2.0) * Float32(pi))) tmp = Float32(0.0) if (t_0 <= Float32(0.0013650000328198075)) tmp = sqrt(Float32(-log1p(Float32(-u1)))); else tmp = Float32(cos(t_0) * sqrt(Float32(u1 * Float32(Float32(1.0) + Float32(u1 * Float32(Float32(0.5) - Float32(u1 * Float32(-0.3333333333333333)))))))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := u2 \cdot \left(2 \cdot \pi\right)\\
\mathbf{if}\;t\_0 \leq 0.0013650000328198075:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)}\\
\mathbf{else}:\\
\;\;\;\;\cos t\_0 \cdot \sqrt{u1 \cdot \left(1 + u1 \cdot \left(0.5 - u1 \cdot -0.3333333333333333\right)\right)}\\
\end{array}
\end{array}
if (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) < 0.00136500003Initial program 59.2%
sub-neg59.2%
log1p-define99.7%
Simplified99.7%
Taylor expanded in u2 around 0 99.2%
if 0.00136500003 < (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) Initial program 57.3%
Taylor expanded in u1 around 0 91.5%
Final simplification95.8%
(FPCore (cosTheta_i u1 u2) :precision binary32 (if (<= (* u2 (* 2.0 PI)) 0.011500000022351742) (sqrt (- (log1p (- u1)))) (* (sqrt u1) (cos (* 2.0 (* PI u2))))))
float code(float cosTheta_i, float u1, float u2) {
float tmp;
if ((u2 * (2.0f * ((float) M_PI))) <= 0.011500000022351742f) {
tmp = sqrtf(-log1pf(-u1));
} else {
tmp = sqrtf(u1) * cosf((2.0f * (((float) M_PI) * u2)));
}
return tmp;
}
function code(cosTheta_i, u1, u2) tmp = Float32(0.0) if (Float32(u2 * Float32(Float32(2.0) * Float32(pi))) <= Float32(0.011500000022351742)) tmp = sqrt(Float32(-log1p(Float32(-u1)))); else tmp = Float32(sqrt(u1) * cos(Float32(Float32(2.0) * Float32(Float32(pi) * u2)))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;u2 \cdot \left(2 \cdot \pi\right) \leq 0.011500000022351742:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{u1} \cdot \cos \left(2 \cdot \left(\pi \cdot u2\right)\right)\\
\end{array}
\end{array}
if (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) < 0.0115Initial program 59.4%
sub-neg59.4%
log1p-define99.5%
Simplified99.5%
Taylor expanded in u2 around 0 95.9%
if 0.0115 < (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) Initial program 56.3%
Taylor expanded in u1 around 0 77.6%
mul-1-neg77.6%
Simplified77.6%
Taylor expanded in u1 around 0 77.6%
Final simplification89.8%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt (- (log1p (- u1)))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-log1pf(-u1));
}
function code(cosTheta_i, u1, u2) return sqrt(Float32(-log1p(Float32(-u1)))) end
\begin{array}{l}
\\
\sqrt{-\mathsf{log1p}\left(-u1\right)}
\end{array}
Initial program 58.4%
sub-neg58.4%
log1p-define99.1%
Simplified99.1%
Taylor expanded in u2 around 0 77.9%
Final simplification77.9%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt (* u1 (+ 1.0 (* u1 (+ 0.5 (* u1 (- 0.3333333333333333 (* u1 -0.25)))))))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 * (1.0f + (u1 * (0.5f + (u1 * (0.3333333333333333f - (u1 * -0.25f))))))));
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt((u1 * (1.0e0 + (u1 * (0.5e0 + (u1 * (0.3333333333333333e0 - (u1 * (-0.25e0)))))))))
end function
function code(cosTheta_i, u1, u2) return sqrt(Float32(u1 * Float32(Float32(1.0) + Float32(u1 * Float32(Float32(0.5) + Float32(u1 * Float32(Float32(0.3333333333333333) - Float32(u1 * Float32(-0.25))))))))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt((u1 * (single(1.0) + (u1 * (single(0.5) + (u1 * (single(0.3333333333333333) - (u1 * single(-0.25))))))))); end
\begin{array}{l}
\\
\sqrt{u1 \cdot \left(1 + u1 \cdot \left(0.5 + u1 \cdot \left(0.3333333333333333 - u1 \cdot -0.25\right)\right)\right)}
\end{array}
Initial program 58.4%
sub-neg58.4%
log1p-define99.1%
Simplified99.1%
Taylor expanded in u2 around 0 77.9%
Taylor expanded in u1 around 0 74.0%
Final simplification74.0%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt (* u1 (+ 1.0 (* u1 (- 0.5 (* u1 -0.3333333333333333)))))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 * (1.0f + (u1 * (0.5f - (u1 * -0.3333333333333333f))))));
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt((u1 * (1.0e0 + (u1 * (0.5e0 - (u1 * (-0.3333333333333333e0)))))))
end function
function code(cosTheta_i, u1, u2) return sqrt(Float32(u1 * Float32(Float32(1.0) + Float32(u1 * Float32(Float32(0.5) - Float32(u1 * Float32(-0.3333333333333333))))))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt((u1 * (single(1.0) + (u1 * (single(0.5) - (u1 * single(-0.3333333333333333))))))); end
\begin{array}{l}
\\
\sqrt{u1 \cdot \left(1 + u1 \cdot \left(0.5 - u1 \cdot -0.3333333333333333\right)\right)}
\end{array}
Initial program 58.4%
sub-neg58.4%
log1p-define99.1%
Simplified99.1%
Taylor expanded in u2 around 0 77.9%
Taylor expanded in u1 around 0 72.7%
Final simplification72.7%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt (* u1 (- 1.0 (* u1 -0.5)))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 * (1.0f - (u1 * -0.5f))));
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt((u1 * (1.0e0 - (u1 * (-0.5e0)))))
end function
function code(cosTheta_i, u1, u2) return sqrt(Float32(u1 * Float32(Float32(1.0) - Float32(u1 * Float32(-0.5))))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt((u1 * (single(1.0) - (u1 * single(-0.5))))); end
\begin{array}{l}
\\
\sqrt{u1 \cdot \left(1 - u1 \cdot -0.5\right)}
\end{array}
Initial program 58.4%
sub-neg58.4%
log1p-define99.1%
Simplified99.1%
Taylor expanded in u2 around 0 77.9%
Taylor expanded in u1 around 0 70.2%
Final simplification70.2%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt u1))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(u1);
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt(u1)
end function
function code(cosTheta_i, u1, u2) return sqrt(u1) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt(u1); end
\begin{array}{l}
\\
\sqrt{u1}
\end{array}
Initial program 58.4%
Taylor expanded in u1 around 0 75.8%
mul-1-neg75.8%
Simplified75.8%
Taylor expanded in u2 around 0 62.9%
Final simplification62.9%
herbie shell --seed 2024067
(FPCore (cosTheta_i u1 u2)
:name "Beckmann Sample, near normal, slope_x"
:precision binary32
:pre (and (and (and (> cosTheta_i 0.9999) (<= cosTheta_i 1.0)) (and (<= 2.328306437e-10 u1) (<= u1 1.0))) (and (<= 2.328306437e-10 u2) (<= u2 1.0)))
(* (sqrt (- (log (- 1.0 u1)))) (cos (* (* 2.0 PI) u2))))