
(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 5 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
(*
(fma (pow x 6.0) 1.7146776406035666e-7 0.004629629629629629)
(*
(/
x
(fma
3.08641975308642e-5
(pow x 4.0)
(- 0.027777777777777776 (* -0.000925925925925926 (* x x)))))
x)))
double code(double x) {
return fma(pow(x, 6.0), 1.7146776406035666e-7, 0.004629629629629629) * ((x / fma(3.08641975308642e-5, pow(x, 4.0), (0.027777777777777776 - (-0.000925925925925926 * (x * x))))) * x);
}
function code(x) return Float64(fma((x ^ 6.0), 1.7146776406035666e-7, 0.004629629629629629) * Float64(Float64(x / fma(3.08641975308642e-5, (x ^ 4.0), Float64(0.027777777777777776 - Float64(-0.000925925925925926 * Float64(x * x))))) * x)) end
code[x_] := N[(N[(N[Power[x, 6.0], $MachinePrecision] * 1.7146776406035666e-7 + 0.004629629629629629), $MachinePrecision] * N[(N[(x / N[(3.08641975308642e-5 * N[Power[x, 4.0], $MachinePrecision] + N[(0.027777777777777776 - N[(-0.000925925925925926 * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left({x}^{6}, 1.7146776406035666 \cdot 10^{-7}, 0.004629629629629629\right) \cdot \left(\frac{x}{\mathsf{fma}\left(3.08641975308642 \cdot 10^{-5}, {x}^{4}, 0.027777777777777776 - -0.000925925925925926 \cdot \left(x \cdot x\right)\right)} \cdot x\right)
\end{array}
Initial program 47.4%
Taylor expanded in x around 0
*-commutativeN/A
unpow2N/A
associate-*r*N/A
lower-*.f64N/A
lower-*.f64N/A
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6495.2
Applied rewrites95.2%
Applied rewrites95.2%
Applied rewrites95.6%
(FPCore (x)
:precision binary64
(*
(/
(* 0.004629629629629629 x)
(fma
(pow x 4.0)
3.08641975308642e-5
(- 0.027777777777777776 (* (* x x) -0.000925925925925926))))
x))
double code(double x) {
return ((0.004629629629629629 * x) / fma(pow(x, 4.0), 3.08641975308642e-5, (0.027777777777777776 - ((x * x) * -0.000925925925925926)))) * x;
}
function code(x) return Float64(Float64(Float64(0.004629629629629629 * x) / fma((x ^ 4.0), 3.08641975308642e-5, Float64(0.027777777777777776 - Float64(Float64(x * x) * -0.000925925925925926)))) * x) end
code[x_] := N[(N[(N[(0.004629629629629629 * x), $MachinePrecision] / N[(N[Power[x, 4.0], $MachinePrecision] * 3.08641975308642e-5 + N[(0.027777777777777776 - N[(N[(x * x), $MachinePrecision] * -0.000925925925925926), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * x), $MachinePrecision]
\begin{array}{l}
\\
\frac{0.004629629629629629 \cdot x}{\mathsf{fma}\left({x}^{4}, 3.08641975308642 \cdot 10^{-5}, 0.027777777777777776 - \left(x \cdot x\right) \cdot -0.000925925925925926\right)} \cdot x
\end{array}
Initial program 47.4%
Taylor expanded in x around 0
*-commutativeN/A
unpow2N/A
associate-*r*N/A
lower-*.f64N/A
lower-*.f64N/A
+-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6495.2
Applied rewrites95.2%
Applied rewrites95.2%
Taylor expanded in x around 0
Applied rewrites95.6%
(FPCore (x)
:precision binary64
(*
(*
(fma
(- (* 0.0003527336860670194 (* x x)) 0.005555555555555556)
(* x x)
0.16666666666666666)
x)
x))
double code(double x) {
return (fma(((0.0003527336860670194 * (x * x)) - 0.005555555555555556), (x * x), 0.16666666666666666) * x) * x;
}
function code(x) return Float64(Float64(fma(Float64(Float64(0.0003527336860670194 * Float64(x * x)) - 0.005555555555555556), Float64(x * x), 0.16666666666666666) * x) * x) end
code[x_] := N[(N[(N[(N[(N[(0.0003527336860670194 * N[(x * x), $MachinePrecision]), $MachinePrecision] - 0.005555555555555556), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.16666666666666666), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision]
\begin{array}{l}
\\
\left(\mathsf{fma}\left(0.0003527336860670194 \cdot \left(x \cdot x\right) - 0.005555555555555556, x \cdot x, 0.16666666666666666\right) \cdot x\right) \cdot x
\end{array}
Initial program 47.4%
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
lower--.f64N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6495.6
Applied rewrites95.6%
(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(Float64(0.16666666666666666 * x) * x) end
function tmp = code(x) tmp = (0.16666666666666666 * x) * x; end
code[x_] := N[(N[(0.16666666666666666 * x), $MachinePrecision] * x), $MachinePrecision]
\begin{array}{l}
\\
\left(0.16666666666666666 \cdot x\right) \cdot x
\end{array}
Initial program 47.4%
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
lower--.f64N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6495.6
Applied rewrites95.6%
Taylor expanded in x around 0
Applied rewrites95.3%
(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(Float64(x * x) * 0.16666666666666666) end
function tmp = code(x) tmp = (x * x) * 0.16666666666666666; end
code[x_] := N[(N[(x * x), $MachinePrecision] * 0.16666666666666666), $MachinePrecision]
\begin{array}{l}
\\
\left(x \cdot x\right) \cdot 0.16666666666666666
\end{array}
Initial program 47.4%
Taylor expanded in x around 0
*-commutativeN/A
lower-*.f64N/A
unpow2N/A
lower-*.f6495.2
Applied rewrites95.2%
(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 2024337
(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)))