
(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
(pow
(expm1
(log1p
(sqrt
(log1p
(fma
0.0001984126984126984
(pow x 6.0)
(fma
x
(* x 0.16666666666666666)
(* (pow x 4.0) 0.008333333333333333)))))))
2.0))
double code(double x) {
return pow(expm1(log1p(sqrt(log1p(fma(0.0001984126984126984, pow(x, 6.0), fma(x, (x * 0.16666666666666666), (pow(x, 4.0) * 0.008333333333333333))))))), 2.0);
}
function code(x) return expm1(log1p(sqrt(log1p(fma(0.0001984126984126984, (x ^ 6.0), fma(x, Float64(x * 0.16666666666666666), Float64((x ^ 4.0) * 0.008333333333333333))))))) ^ 2.0 end
code[x_] := N[Power[N[(Exp[N[Log[1 + N[Sqrt[N[Log[1 + N[(0.0001984126984126984 * N[Power[x, 6.0], $MachinePrecision] + N[(x * N[(x * 0.16666666666666666), $MachinePrecision] + N[(N[Power[x, 4.0], $MachinePrecision] * 0.008333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]], $MachinePrecision]] - 1), $MachinePrecision], 2.0], $MachinePrecision]
\begin{array}{l}
\\
{\left(\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\mathsf{log1p}\left(\mathsf{fma}\left(0.0001984126984126984, {x}^{6}, \mathsf{fma}\left(x, x \cdot 0.16666666666666666, {x}^{4} \cdot 0.008333333333333333\right)\right)\right)}\right)\right)\right)}^{2}
\end{array}
Initial program 54.5%
add-sqr-sqrt54.5%
pow254.5%
Applied egg-rr54.5%
Taylor expanded in x around 0 54.2%
expm1-log1p-u54.2%
log1p-def96.6%
fma-def96.6%
+-commutative96.6%
pow296.6%
associate-*l*96.6%
*-commutative96.6%
fma-def96.6%
*-commutative96.6%
*-commutative96.6%
Applied egg-rr96.6%
Final simplification96.6%
(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(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 54.5%
Taylor expanded in x around 0 96.5%
unpow296.5%
Simplified96.5%
Final simplification96.5%
(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 54.5%
add-sqr-sqrt54.5%
pow254.5%
Applied egg-rr54.5%
Taylor expanded in x around 0 96.4%
unpow296.4%
swap-sqr96.5%
add-sqr-sqrt96.5%
*-commutative96.5%
associate-*r*96.5%
Applied egg-rr96.5%
Final simplification96.5%
(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 54.5%
add-sqr-sqrt54.5%
pow254.5%
Applied egg-rr54.5%
Taylor expanded in x around 0 96.4%
unpow296.4%
swap-sqr96.5%
add-sqr-sqrt96.5%
*-commutative96.5%
associate-*r*96.5%
Applied egg-rr96.5%
*-commutative96.5%
metadata-eval96.5%
div-inv96.5%
Applied egg-rr96.5%
Final simplification96.5%
(FPCore (x) :precision binary64 (/ x (/ 6.0 x)))
double code(double x) {
return x / (6.0 / x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = x / (6.0d0 / x)
end function
public static double code(double x) {
return x / (6.0 / x);
}
def code(x): return x / (6.0 / x)
function code(x) return Float64(x / Float64(6.0 / x)) end
function tmp = code(x) tmp = x / (6.0 / x); end
code[x_] := N[(x / N[(6.0 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{x}{\frac{6}{x}}
\end{array}
Initial program 54.5%
add-sqr-sqrt54.5%
pow254.5%
Applied egg-rr54.5%
Taylor expanded in x around 0 96.4%
unpow296.4%
swap-sqr96.5%
add-sqr-sqrt96.5%
metadata-eval96.5%
div-inv96.5%
Applied egg-rr96.5%
associate-/l*96.6%
Simplified96.6%
Final simplification96.6%
(FPCore (x) :precision binary64 0.0)
double code(double x) {
return 0.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = 0.0d0
end function
public static double code(double x) {
return 0.0;
}
def code(x): return 0.0
function code(x) return 0.0 end
function tmp = code(x) tmp = 0.0; end
code[x_] := 0.0
\begin{array}{l}
\\
0
\end{array}
Initial program 54.5%
add-sqr-sqrt54.5%
pow254.5%
Applied egg-rr54.5%
Taylor expanded in x around 0 96.4%
unpow296.4%
swap-sqr96.5%
add-sqr-sqrt96.5%
*-commutative96.5%
expm1-log1p-u96.5%
expm1-udef53.9%
log1p-udef53.9%
add-exp-log53.9%
Applied egg-rr53.9%
associate--l+53.9%
fma-neg53.9%
metadata-eval53.9%
Simplified53.9%
Taylor expanded in x around 0 53.4%
Final simplification53.4%
(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 2023292
(FPCore (x)
:name "bug500, discussion (missed optimization)"
:precision binary64
:herbie-target
(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)))
(log (/ (sinh x) x)))