
(FPCore (x) :precision binary32 (acosh x))
float code(float x) {
return acoshf(x);
}
function code(x) return acosh(x) end
function tmp = code(x) tmp = acosh(x); end
\begin{array}{l}
\\
\cosh^{-1} x
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary32 (log (+ x (sqrt (- (* x x) 1.0)))))
float code(float x) {
return logf((x + sqrtf(((x * x) - 1.0f))));
}
real(4) function code(x)
real(4), intent (in) :: x
code = log((x + sqrt(((x * x) - 1.0e0))))
end function
function code(x) return log(Float32(x + sqrt(Float32(Float32(x * x) - Float32(1.0))))) end
function tmp = code(x) tmp = log((x + sqrt(((x * x) - single(1.0))))); end
\begin{array}{l}
\\
\log \left(x + \sqrt{x \cdot x - 1}\right)
\end{array}
(FPCore (x) :precision binary32 (log (- (* x 2.0) (/ 0.5 x))))
float code(float x) {
return logf(((x * 2.0f) - (0.5f / x)));
}
real(4) function code(x)
real(4), intent (in) :: x
code = log(((x * 2.0e0) - (0.5e0 / x)))
end function
function code(x) return log(Float32(Float32(x * Float32(2.0)) - Float32(Float32(0.5) / x))) end
function tmp = code(x) tmp = log(((x * single(2.0)) - (single(0.5) / x))); end
\begin{array}{l}
\\
\log \left(x \cdot 2 - \frac{0.5}{x}\right)
\end{array}
Initial program 51.0%
Taylor expanded in x around inf 99.1%
*-commutative99.1%
associate-*r/99.1%
metadata-eval99.1%
Simplified99.1%
Final simplification99.1%
(FPCore (x) :precision binary32 (log (+ x -1.0)))
float code(float x) {
return logf((x + -1.0f));
}
real(4) function code(x)
real(4), intent (in) :: x
code = log((x + (-1.0e0)))
end function
function code(x) return log(Float32(x + Float32(-1.0))) end
function tmp = code(x) tmp = log((x + single(-1.0))); end
\begin{array}{l}
\\
\log \left(x + -1\right)
\end{array}
Initial program 51.0%
pow1/251.0%
pow-to-exp50.8%
fma-neg50.8%
metadata-eval50.8%
Applied egg-rr50.8%
Taylor expanded in x around 0 -0.0%
Simplified44.3%
Final simplification44.3%
(FPCore (x) :precision binary32 (log (+ x x)))
float code(float x) {
return logf((x + x));
}
real(4) function code(x)
real(4), intent (in) :: x
code = log((x + x))
end function
function code(x) return log(Float32(x + x)) end
function tmp = code(x) tmp = log((x + x)); end
\begin{array}{l}
\\
\log \left(x + x\right)
\end{array}
Initial program 51.0%
Taylor expanded in x around inf 97.9%
Final simplification97.9%
(FPCore (x) :precision binary32 (* x 0.3333333333333333))
float code(float x) {
return x * 0.3333333333333333f;
}
real(4) function code(x)
real(4), intent (in) :: x
code = x * 0.3333333333333333e0
end function
function code(x) return Float32(x * Float32(0.3333333333333333)) end
function tmp = code(x) tmp = x * single(0.3333333333333333); end
\begin{array}{l}
\\
x \cdot 0.3333333333333333
\end{array}
Initial program 51.0%
add-cbrt-cube35.3%
pow1/335.0%
log-pow34.9%
pow334.9%
log-pow50.5%
fma-neg50.5%
metadata-eval50.5%
Applied egg-rr50.5%
Taylor expanded in x around 0 -0.0%
Simplified11.4%
Taylor expanded in x around inf 11.5%
*-commutative11.5%
Simplified11.5%
Final simplification11.5%
(FPCore (x) :precision binary32 (/ x x))
float code(float x) {
return x / x;
}
real(4) function code(x)
real(4), intent (in) :: x
code = x / x
end function
function code(x) return Float32(x / x) end
function tmp = code(x) tmp = x / x; end
\begin{array}{l}
\\
\frac{x}{x}
\end{array}
Initial program 51.0%
add-cbrt-cube35.3%
pow1/335.0%
log-pow34.9%
pow334.9%
log-pow50.5%
fma-neg50.5%
metadata-eval50.5%
Applied egg-rr50.5%
Taylor expanded in x around 0 -0.0%
Simplified11.4%
Applied egg-rr19.7%
associate-/l*19.4%
div-inv19.4%
+-commutative19.4%
div-inv19.4%
metadata-eval19.4%
Applied egg-rr19.4%
Simplified21.0%
Final simplification21.0%
(FPCore (x) :precision binary32 -0.3333333333333333)
float code(float x) {
return -0.3333333333333333f;
}
real(4) function code(x)
real(4), intent (in) :: x
code = -0.3333333333333333e0
end function
function code(x) return Float32(-0.3333333333333333) end
function tmp = code(x) tmp = single(-0.3333333333333333); end
\begin{array}{l}
\\
-0.3333333333333333
\end{array}
Initial program 51.0%
add-cbrt-cube35.3%
pow1/335.0%
log-pow34.9%
pow334.9%
log-pow50.5%
fma-neg50.5%
metadata-eval50.5%
Applied egg-rr50.5%
Taylor expanded in x around 0 -0.0%
Simplified11.4%
Taylor expanded in x around 0 3.1%
Final simplification3.1%
(FPCore (x) :precision binary32 (log (+ x (* (sqrt (- x 1.0)) (sqrt (+ x 1.0))))))
float code(float x) {
return logf((x + (sqrtf((x - 1.0f)) * sqrtf((x + 1.0f)))));
}
real(4) function code(x)
real(4), intent (in) :: x
code = log((x + (sqrt((x - 1.0e0)) * sqrt((x + 1.0e0)))))
end function
function code(x) return log(Float32(x + Float32(sqrt(Float32(x - Float32(1.0))) * sqrt(Float32(x + Float32(1.0)))))) end
function tmp = code(x) tmp = log((x + (sqrt((x - single(1.0))) * sqrt((x + single(1.0)))))); end
\begin{array}{l}
\\
\log \left(x + \sqrt{x - 1} \cdot \sqrt{x + 1}\right)
\end{array}
herbie shell --seed 2024024
(FPCore (x)
:name "Rust f32::acosh"
:precision binary32
:pre (>= x 1.0)
:herbie-target
(log (+ x (* (sqrt (- x 1.0)) (sqrt (+ x 1.0)))))
(log (+ x (sqrt (- (* x x) 1.0)))))