
(FPCore (x) :precision binary32 (copysign (log (+ (fabs x) (sqrt (+ (* x x) 1.0)))) x))
float code(float x) {
return copysignf(logf((fabsf(x) + sqrtf(((x * x) + 1.0f)))), x);
}
function code(x) return copysign(log(Float32(abs(x) + sqrt(Float32(Float32(x * x) + Float32(1.0))))), x) end
function tmp = code(x) tmp = sign(x) * abs(log((abs(x) + sqrt(((x * x) + single(1.0)))))); end
\begin{array}{l}
\\
\mathsf{copysign}\left(\log \left(\left|x\right| + \sqrt{x \cdot x + 1}\right), x\right)
\end{array}
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary32 (copysign (log (+ (fabs x) (sqrt (+ (* x x) 1.0)))) x))
float code(float x) {
return copysignf(logf((fabsf(x) + sqrtf(((x * x) + 1.0f)))), x);
}
function code(x) return copysign(log(Float32(abs(x) + sqrt(Float32(Float32(x * x) + Float32(1.0))))), x) end
function tmp = code(x) tmp = sign(x) * abs(log((abs(x) + sqrt(((x * x) + single(1.0)))))); end
\begin{array}{l}
\\
\mathsf{copysign}\left(\log \left(\left|x\right| + \sqrt{x \cdot x + 1}\right), x\right)
\end{array}
(FPCore (x) :precision binary32 (copysign (asinh x) x))
float code(float x) {
return copysignf(asinhf(x), x);
}
function code(x) return copysign(asinh(x), x) end
function tmp = code(x) tmp = sign(x) * abs(asinh(x)); end
\begin{array}{l}
\\
\mathsf{copysign}\left(\sinh^{-1} x, x\right)
\end{array}
Initial program 37.8%
lift-log.f32N/A
lift-+.f32N/A
lift-fabs.f32N/A
lift-sqrt.f32N/A
lift-*.f32N/A
lift-+.f32N/A
sqr-abs-revN/A
asinh-def-revN/A
rem-sqrt-square-revN/A
pow2N/A
sqrt-pow1N/A
metadata-evalN/A
unpow1N/A
lower-asinh.f3299.5
Applied rewrites99.5%
(FPCore (x) :precision binary32 (if (<= x -10.0) (copysign (log (- x)) x) (if (<= x 2.0) (copysign x x) (copysign (log (+ x x)) x))))
float code(float x) {
float tmp;
if (x <= -10.0f) {
tmp = copysignf(logf(-x), x);
} else if (x <= 2.0f) {
tmp = copysignf(x, x);
} else {
tmp = copysignf(logf((x + x)), x);
}
return tmp;
}
function code(x) tmp = Float32(0.0) if (x <= Float32(-10.0)) tmp = copysign(log(Float32(-x)), x); elseif (x <= Float32(2.0)) tmp = copysign(x, x); else tmp = copysign(log(Float32(x + x)), x); end return tmp end
function tmp_2 = code(x) tmp = single(0.0); if (x <= single(-10.0)) tmp = sign(x) * abs(log(-x)); elseif (x <= single(2.0)) tmp = sign(x) * abs(x); else tmp = sign(x) * abs(log((x + x))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -10:\\
\;\;\;\;\mathsf{copysign}\left(\log \left(-x\right), x\right)\\
\mathbf{elif}\;x \leq 2:\\
\;\;\;\;\mathsf{copysign}\left(x, x\right)\\
\mathbf{else}:\\
\;\;\;\;\mathsf{copysign}\left(\log \left(x + x\right), x\right)\\
\end{array}
\end{array}
if x < -10Initial program 50.6%
Taylor expanded in x around -inf
mul-1-negN/A
lower-neg.f3244.6
Applied rewrites44.6%
if -10 < x < 2Initial program 23.8%
lift-log.f32N/A
lift-+.f32N/A
lift-fabs.f32N/A
lift-sqrt.f32N/A
lift-*.f32N/A
lift-+.f32N/A
sqr-abs-revN/A
asinh-def-revN/A
rem-sqrt-square-revN/A
pow2N/A
sqrt-pow1N/A
metadata-evalN/A
unpow1N/A
lower-asinh.f3299.9
Applied rewrites99.9%
Taylor expanded in x around 0
unpow196.2
metadata-eval96.2
sqrt-pow196.2
pow296.2
rem-sqrt-square-rev96.2
asinh-def-rev96.2
sqr-abs-rev96.2
pow296.2
+-commutative96.2
+-commutative96.2
pow296.2
Applied rewrites96.2%
if 2 < x Initial program 53.3%
lift-+.f32N/A
lift-fabs.f32N/A
lift-sqrt.f32N/A
lift-*.f32N/A
lift-+.f32N/A
+-commutativeN/A
rem-sqrt-square-revN/A
pow2N/A
sqrt-pow1N/A
metadata-evalN/A
unpow1N/A
lower-+.f32N/A
lower-sqrt.f32N/A
lower-fma.f3253.3
Applied rewrites53.3%
Taylor expanded in x around inf
Applied rewrites97.4%
(FPCore (x)
:precision binary32
(let* ((t_0 (copysign (log (+ (fabs x) (sqrt (+ (* x x) 1.0)))) x)))
(if (<= t_0 -2.0)
(copysign (log (- x)) x)
(if (<= t_0 1.0) (copysign x x) (copysign (log (- x -1.0)) x)))))
float code(float x) {
float t_0 = copysignf(logf((fabsf(x) + sqrtf(((x * x) + 1.0f)))), x);
float tmp;
if (t_0 <= -2.0f) {
tmp = copysignf(logf(-x), x);
} else if (t_0 <= 1.0f) {
tmp = copysignf(x, x);
} else {
tmp = copysignf(logf((x - -1.0f)), x);
}
return tmp;
}
function code(x) t_0 = copysign(log(Float32(abs(x) + sqrt(Float32(Float32(x * x) + Float32(1.0))))), x) tmp = Float32(0.0) if (t_0 <= Float32(-2.0)) tmp = copysign(log(Float32(-x)), x); elseif (t_0 <= Float32(1.0)) tmp = copysign(x, x); else tmp = copysign(log(Float32(x - Float32(-1.0))), x); end return tmp end
function tmp_2 = code(x) t_0 = sign(x) * abs(log((abs(x) + sqrt(((x * x) + single(1.0)))))); tmp = single(0.0); if (t_0 <= single(-2.0)) tmp = sign(x) * abs(log(-x)); elseif (t_0 <= single(1.0)) tmp = sign(x) * abs(x); else tmp = sign(x) * abs(log((x - single(-1.0)))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{copysign}\left(\log \left(\left|x\right| + \sqrt{x \cdot x + 1}\right), x\right)\\
\mathbf{if}\;t\_0 \leq -2:\\
\;\;\;\;\mathsf{copysign}\left(\log \left(-x\right), x\right)\\
\mathbf{elif}\;t\_0 \leq 1:\\
\;\;\;\;\mathsf{copysign}\left(x, x\right)\\
\mathbf{else}:\\
\;\;\;\;\mathsf{copysign}\left(\log \left(x - -1\right), x\right)\\
\end{array}
\end{array}
if (copysign.f32 (log.f32 (+.f32 (fabs.f32 x) (sqrt.f32 (+.f32 (*.f32 x x) #s(literal 1 binary32))))) x) < -2Initial program 51.2%
Taylor expanded in x around -inf
mul-1-negN/A
lower-neg.f3244.4
Applied rewrites44.4%
if -2 < (copysign.f32 (log.f32 (+.f32 (fabs.f32 x) (sqrt.f32 (+.f32 (*.f32 x x) #s(literal 1 binary32))))) x) < 1Initial program 23.0%
lift-log.f32N/A
lift-+.f32N/A
lift-fabs.f32N/A
lift-sqrt.f32N/A
lift-*.f32N/A
lift-+.f32N/A
sqr-abs-revN/A
asinh-def-revN/A
rem-sqrt-square-revN/A
pow2N/A
sqrt-pow1N/A
metadata-evalN/A
unpow1N/A
lower-asinh.f3299.9
Applied rewrites99.9%
Taylor expanded in x around 0
unpow196.9
metadata-eval96.9
sqrt-pow196.9
pow296.9
rem-sqrt-square-rev96.9
asinh-def-rev96.9
sqr-abs-rev96.9
pow296.9
+-commutative96.9
+-commutative96.9
pow296.9
Applied rewrites96.9%
if 1 < (copysign.f32 (log.f32 (+.f32 (fabs.f32 x) (sqrt.f32 (+.f32 (*.f32 x x) #s(literal 1 binary32))))) x) Initial program 53.6%
lift-+.f32N/A
lift-fabs.f32N/A
lift-sqrt.f32N/A
lift-*.f32N/A
lift-+.f32N/A
+-commutativeN/A
rem-sqrt-square-revN/A
pow2N/A
sqrt-pow1N/A
metadata-evalN/A
unpow1N/A
lower-+.f32N/A
lower-sqrt.f32N/A
lower-fma.f3253.6
Applied rewrites53.6%
Taylor expanded in x around -inf
lower-/.f32-0.0
Applied rewrites-0.0%
Taylor expanded in x around 0
+-commutativeN/A
metadata-evalN/A
fp-cancel-sign-sub-invN/A
metadata-evalN/A
metadata-evalN/A
lower--.f3244.2
Applied rewrites44.2%
(FPCore (x)
:precision binary32
(let* ((t_0 (copysign (log (+ (fabs x) (sqrt (+ (* x x) 1.0)))) x)))
(if (<= t_0 -2.0)
(copysign (log (- x)) x)
(if (<= t_0 1.0) (copysign x x) (copysign (log x) x)))))
float code(float x) {
float t_0 = copysignf(logf((fabsf(x) + sqrtf(((x * x) + 1.0f)))), x);
float tmp;
if (t_0 <= -2.0f) {
tmp = copysignf(logf(-x), x);
} else if (t_0 <= 1.0f) {
tmp = copysignf(x, x);
} else {
tmp = copysignf(logf(x), x);
}
return tmp;
}
function code(x) t_0 = copysign(log(Float32(abs(x) + sqrt(Float32(Float32(x * x) + Float32(1.0))))), x) tmp = Float32(0.0) if (t_0 <= Float32(-2.0)) tmp = copysign(log(Float32(-x)), x); elseif (t_0 <= Float32(1.0)) tmp = copysign(x, x); else tmp = copysign(log(x), x); end return tmp end
function tmp_2 = code(x) t_0 = sign(x) * abs(log((abs(x) + sqrt(((x * x) + single(1.0)))))); tmp = single(0.0); if (t_0 <= single(-2.0)) tmp = sign(x) * abs(log(-x)); elseif (t_0 <= single(1.0)) tmp = sign(x) * abs(x); else tmp = sign(x) * abs(log(x)); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{copysign}\left(\log \left(\left|x\right| + \sqrt{x \cdot x + 1}\right), x\right)\\
\mathbf{if}\;t\_0 \leq -2:\\
\;\;\;\;\mathsf{copysign}\left(\log \left(-x\right), x\right)\\
\mathbf{elif}\;t\_0 \leq 1:\\
\;\;\;\;\mathsf{copysign}\left(x, x\right)\\
\mathbf{else}:\\
\;\;\;\;\mathsf{copysign}\left(\log x, x\right)\\
\end{array}
\end{array}
if (copysign.f32 (log.f32 (+.f32 (fabs.f32 x) (sqrt.f32 (+.f32 (*.f32 x x) #s(literal 1 binary32))))) x) < -2Initial program 51.2%
Taylor expanded in x around -inf
mul-1-negN/A
lower-neg.f3244.4
Applied rewrites44.4%
if -2 < (copysign.f32 (log.f32 (+.f32 (fabs.f32 x) (sqrt.f32 (+.f32 (*.f32 x x) #s(literal 1 binary32))))) x) < 1Initial program 23.0%
lift-log.f32N/A
lift-+.f32N/A
lift-fabs.f32N/A
lift-sqrt.f32N/A
lift-*.f32N/A
lift-+.f32N/A
sqr-abs-revN/A
asinh-def-revN/A
rem-sqrt-square-revN/A
pow2N/A
sqrt-pow1N/A
metadata-evalN/A
unpow1N/A
lower-asinh.f3299.9
Applied rewrites99.9%
Taylor expanded in x around 0
unpow196.9
metadata-eval96.9
sqrt-pow196.9
pow296.9
rem-sqrt-square-rev96.9
asinh-def-rev96.9
sqr-abs-rev96.9
pow296.9
+-commutative96.9
+-commutative96.9
pow296.9
Applied rewrites96.9%
if 1 < (copysign.f32 (log.f32 (+.f32 (fabs.f32 x) (sqrt.f32 (+.f32 (*.f32 x x) #s(literal 1 binary32))))) x) Initial program 53.6%
Taylor expanded in x around inf
Applied rewrites44.1%
(FPCore (x) :precision binary32 (if (<= (copysign (log (+ (fabs x) (sqrt (+ (* x x) 1.0)))) x) 1.0) (copysign x x) (copysign (log x) x)))
float code(float x) {
float tmp;
if (copysignf(logf((fabsf(x) + sqrtf(((x * x) + 1.0f)))), x) <= 1.0f) {
tmp = copysignf(x, x);
} else {
tmp = copysignf(logf(x), x);
}
return tmp;
}
function code(x) tmp = Float32(0.0) if (copysign(log(Float32(abs(x) + sqrt(Float32(Float32(x * x) + Float32(1.0))))), x) <= Float32(1.0)) tmp = copysign(x, x); else tmp = copysign(log(x), x); end return tmp end
function tmp_2 = code(x) tmp = single(0.0); if ((sign(x) * abs(log((abs(x) + sqrt(((x * x) + single(1.0))))))) <= single(1.0)) tmp = sign(x) * abs(x); else tmp = sign(x) * abs(log(x)); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\mathsf{copysign}\left(\log \left(\left|x\right| + \sqrt{x \cdot x + 1}\right), x\right) \leq 1:\\
\;\;\;\;\mathsf{copysign}\left(x, x\right)\\
\mathbf{else}:\\
\;\;\;\;\mathsf{copysign}\left(\log x, x\right)\\
\end{array}
\end{array}
if (copysign.f32 (log.f32 (+.f32 (fabs.f32 x) (sqrt.f32 (+.f32 (*.f32 x x) #s(literal 1 binary32))))) x) < 1Initial program 32.5%
lift-log.f32N/A
lift-+.f32N/A
lift-fabs.f32N/A
lift-sqrt.f32N/A
lift-*.f32N/A
lift-+.f32N/A
sqr-abs-revN/A
asinh-def-revN/A
rem-sqrt-square-revN/A
pow2N/A
sqrt-pow1N/A
metadata-evalN/A
unpow1N/A
lower-asinh.f3299.7
Applied rewrites99.7%
Taylor expanded in x around 0
unpow168.1
metadata-eval68.1
sqrt-pow168.1
pow268.1
rem-sqrt-square-rev68.1
asinh-def-rev68.1
sqr-abs-rev68.1
pow268.1
+-commutative68.1
+-commutative68.1
pow268.1
Applied rewrites68.1%
if 1 < (copysign.f32 (log.f32 (+.f32 (fabs.f32 x) (sqrt.f32 (+.f32 (*.f32 x x) #s(literal 1 binary32))))) x) Initial program 53.6%
Taylor expanded in x around inf
Applied rewrites44.1%
(FPCore (x) :precision binary32 (copysign x x))
float code(float x) {
return copysignf(x, x);
}
function code(x) return copysign(x, x) end
function tmp = code(x) tmp = sign(x) * abs(x); end
\begin{array}{l}
\\
\mathsf{copysign}\left(x, x\right)
\end{array}
Initial program 37.8%
lift-log.f32N/A
lift-+.f32N/A
lift-fabs.f32N/A
lift-sqrt.f32N/A
lift-*.f32N/A
lift-+.f32N/A
sqr-abs-revN/A
asinh-def-revN/A
rem-sqrt-square-revN/A
pow2N/A
sqrt-pow1N/A
metadata-evalN/A
unpow1N/A
lower-asinh.f3299.5
Applied rewrites99.5%
Taylor expanded in x around 0
unpow153.9
metadata-eval53.9
sqrt-pow153.9
pow253.9
rem-sqrt-square-rev53.9
asinh-def-rev53.9
sqr-abs-rev53.9
pow253.9
+-commutative53.9
+-commutative53.9
pow253.9
Applied rewrites53.9%
(FPCore (x) :precision binary32 (let* ((t_0 (/ 1.0 (fabs x)))) (copysign (log1p (+ (fabs x) (/ (fabs x) (+ (hypot 1.0 t_0) t_0)))) x)))
float code(float x) {
float t_0 = 1.0f / fabsf(x);
return copysignf(log1pf((fabsf(x) + (fabsf(x) / (hypotf(1.0f, t_0) + t_0)))), x);
}
function code(x) t_0 = Float32(Float32(1.0) / abs(x)) return copysign(log1p(Float32(abs(x) + Float32(abs(x) / Float32(hypot(Float32(1.0), t_0) + t_0)))), x) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{1}{\left|x\right|}\\
\mathsf{copysign}\left(\mathsf{log1p}\left(\left|x\right| + \frac{\left|x\right|}{\mathsf{hypot}\left(1, t\_0\right) + t\_0}\right), x\right)
\end{array}
\end{array}
herbie shell --seed 2025112
(FPCore (x)
:name "Rust f32::asinh"
:precision binary32
:alt
(! :herbie-platform c (let* ((ax (fabs x)) (ix (/ 1 ax))) (copysign (log1p (+ ax (/ ax (+ (hypot 1 ix) ix)))) x)))
(copysign (log (+ (fabs x) (sqrt (+ (* x x) 1.0)))) x))