
(FPCore (x) :precision binary64 (log (/ (sinh x) x)))
double code(double x) {
return log((sinh(x) / x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = log((sinh(x) / x))
end function
public static double code(double x) {
return Math.log((Math.sinh(x) / x));
}
def code(x): return math.log((math.sinh(x) / x))
function code(x) return log(Float64(sinh(x) / x)) end
function tmp = code(x) tmp = log((sinh(x) / x)); end
code[x_] := N[Log[N[(N[Sinh[x], $MachinePrecision] / x), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\log \left(\frac{\sinh x}{x}\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (log (/ (sinh x) x)))
double code(double x) {
return log((sinh(x) / x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = log((sinh(x) / x))
end function
public static double code(double x) {
return Math.log((Math.sinh(x) / x));
}
def code(x): return math.log((math.sinh(x) / x))
function code(x) return log(Float64(sinh(x) / x)) end
function tmp = code(x) tmp = log((sinh(x) / x)); end
code[x_] := N[Log[N[(N[Sinh[x], $MachinePrecision] / x), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\log \left(\frac{\sinh x}{x}\right)
\end{array}
(FPCore (x) :precision binary64 (* x (/ x (fma x (* x 0.2) 6.0))))
double code(double x) {
return x * (x / fma(x, (x * 0.2), 6.0));
}
function code(x) return Float64(x * Float64(x / fma(x, Float64(x * 0.2), 6.0))) end
code[x_] := N[(x * N[(x / N[(x * N[(x * 0.2), $MachinePrecision] + 6.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \frac{x}{\mathsf{fma}\left(x, x \cdot 0.2, 6\right)}
\end{array}
Initial program 53.8%
Taylor expanded in x around 0
unpow2N/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6498.4
Applied rewrites98.4%
Applied rewrites98.5%
Taylor expanded in x around 0
Applied rewrites98.6%
Applied rewrites98.7%
Final simplification98.7%
(FPCore (x) :precision binary64 (* x (fma (* -0.005555555555555556 (* x x)) x (* x 0.16666666666666666))))
double code(double x) {
return x * fma((-0.005555555555555556 * (x * x)), x, (x * 0.16666666666666666));
}
function code(x) return Float64(x * fma(Float64(-0.005555555555555556 * Float64(x * x)), x, Float64(x * 0.16666666666666666))) end
code[x_] := N[(x * N[(N[(-0.005555555555555556 * N[(x * x), $MachinePrecision]), $MachinePrecision] * x + N[(x * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \mathsf{fma}\left(-0.005555555555555556 \cdot \left(x \cdot x\right), x, x \cdot 0.16666666666666666\right)
\end{array}
Initial program 53.8%
Taylor expanded in x around 0
unpow2N/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6498.4
Applied rewrites98.4%
Applied rewrites98.4%
Final simplification98.4%
(FPCore (x) :precision binary64 (* x (* x (fma (* x x) -0.005555555555555556 0.16666666666666666))))
double code(double x) {
return x * (x * fma((x * x), -0.005555555555555556, 0.16666666666666666));
}
function code(x) return Float64(x * Float64(x * fma(Float64(x * x), -0.005555555555555556, 0.16666666666666666))) end
code[x_] := N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * -0.005555555555555556 + 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(x \cdot \mathsf{fma}\left(x \cdot x, -0.005555555555555556, 0.16666666666666666\right)\right)
\end{array}
Initial program 53.8%
Taylor expanded in x around 0
unpow2N/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6498.4
Applied rewrites98.4%
(FPCore (x) :precision binary64 (* x (/ x 6.0)))
double code(double x) {
return x * (x / 6.0);
}
real(8) function code(x)
real(8), intent (in) :: x
code = x * (x / 6.0d0)
end function
public static double code(double x) {
return x * (x / 6.0);
}
def code(x): return x * (x / 6.0)
function code(x) return Float64(x * Float64(x / 6.0)) end
function tmp = code(x) tmp = x * (x / 6.0); end
code[x_] := N[(x * N[(x / 6.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \frac{x}{6}
\end{array}
Initial program 53.8%
Taylor expanded in x around 0
unpow2N/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6498.4
Applied rewrites98.4%
Applied rewrites98.5%
Taylor expanded in x around 0
Applied rewrites98.3%
Applied rewrites98.4%
Final simplification98.4%
(FPCore (x) :precision binary64 (* x (* x 0.16666666666666666)))
double code(double x) {
return x * (x * 0.16666666666666666);
}
real(8) function code(x)
real(8), intent (in) :: x
code = x * (x * 0.16666666666666666d0)
end function
public static double code(double x) {
return x * (x * 0.16666666666666666);
}
def code(x): return x * (x * 0.16666666666666666)
function code(x) return Float64(x * Float64(x * 0.16666666666666666)) end
function tmp = code(x) tmp = x * (x * 0.16666666666666666); end
code[x_] := N[(x * N[(x * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(x \cdot 0.16666666666666666\right)
\end{array}
Initial program 53.8%
Taylor expanded in x around 0
lower-*.f64N/A
unpow2N/A
lower-*.f6498.2
Applied rewrites98.2%
Applied rewrites98.2%
Final simplification98.2%
(FPCore (x) :precision binary64 (* 0.16666666666666666 (* x x)))
double code(double x) {
return 0.16666666666666666 * (x * x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.16666666666666666d0 * (x * x)
end function
public static double code(double x) {
return 0.16666666666666666 * (x * x);
}
def code(x): return 0.16666666666666666 * (x * x)
function code(x) return Float64(0.16666666666666666 * Float64(x * x)) end
function tmp = code(x) tmp = 0.16666666666666666 * (x * x); end
code[x_] := N[(0.16666666666666666 * N[(x * x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
0.16666666666666666 \cdot \left(x \cdot x\right)
\end{array}
Initial program 53.8%
Taylor expanded in x around 0
lower-*.f64N/A
unpow2N/A
lower-*.f6498.2
Applied rewrites98.2%
(FPCore (x)
:precision binary64
(if (< (fabs x) 0.085)
(*
(* x x)
(fma
(fma
(fma -2.6455026455026456e-5 (* x x) 0.0003527336860670194)
(* x x)
-0.005555555555555556)
(* x x)
0.16666666666666666))
(log (/ (sinh x) x))))
double code(double x) {
double tmp;
if (fabs(x) < 0.085) {
tmp = (x * x) * fma(fma(fma(-2.6455026455026456e-5, (x * x), 0.0003527336860670194), (x * x), -0.005555555555555556), (x * x), 0.16666666666666666);
} else {
tmp = log((sinh(x) / x));
}
return tmp;
}
function code(x) tmp = 0.0 if (abs(x) < 0.085) tmp = Float64(Float64(x * x) * fma(fma(fma(-2.6455026455026456e-5, Float64(x * x), 0.0003527336860670194), Float64(x * x), -0.005555555555555556), Float64(x * x), 0.16666666666666666)); else tmp = log(Float64(sinh(x) / x)); end return tmp end
code[x_] := If[Less[N[Abs[x], $MachinePrecision], 0.085], N[(N[(x * x), $MachinePrecision] * N[(N[(N[(-2.6455026455026456e-5 * N[(x * x), $MachinePrecision] + 0.0003527336860670194), $MachinePrecision] * N[(x * x), $MachinePrecision] + -0.005555555555555556), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.16666666666666666), $MachinePrecision]), $MachinePrecision], N[Log[N[(N[Sinh[x], $MachinePrecision] / x), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\left|x\right| < 0.085:\\
\;\;\;\;\left(x \cdot x\right) \cdot \mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-2.6455026455026456 \cdot 10^{-5}, x \cdot x, 0.0003527336860670194\right), x \cdot x, -0.005555555555555556\right), x \cdot x, 0.16666666666666666\right)\\
\mathbf{else}:\\
\;\;\;\;\log \left(\frac{\sinh x}{x}\right)\\
\end{array}
\end{array}
herbie shell --seed 2024223
(FPCore (x)
:name "bug500, discussion (missed optimization)"
:precision binary64
:alt
(! :herbie-platform default (if (< (fabs x) 17/200) (let ((x2 (* x x))) (* x2 (fma (fma (fma -1/37800 x2 1/2835) x2 -1/180) x2 1/6))) (log (/ (sinh x) x))))
(log (/ (sinh x) x)))