
(FPCore (x y) :precision binary64 (+ (+ (+ (* x x) (* y y)) (* y y)) (* y y)))
double code(double x, double y) {
return (((x * x) + (y * y)) + (y * y)) + (y * y);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (((x * x) + (y * y)) + (y * y)) + (y * y)
end function
public static double code(double x, double y) {
return (((x * x) + (y * y)) + (y * y)) + (y * y);
}
def code(x, y): return (((x * x) + (y * y)) + (y * y)) + (y * y)
function code(x, y) return Float64(Float64(Float64(Float64(x * x) + Float64(y * y)) + Float64(y * y)) + Float64(y * y)) end
function tmp = code(x, y) tmp = (((x * x) + (y * y)) + (y * y)) + (y * y); end
code[x_, y_] := N[(N[(N[(N[(x * x), $MachinePrecision] + N[(y * y), $MachinePrecision]), $MachinePrecision] + N[(y * y), $MachinePrecision]), $MachinePrecision] + N[(y * y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(x \cdot x + y \cdot y\right) + y \cdot y\right) + y \cdot y
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 8 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (+ (+ (+ (* x x) (* y y)) (* y y)) (* y y)))
double code(double x, double y) {
return (((x * x) + (y * y)) + (y * y)) + (y * y);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (((x * x) + (y * y)) + (y * y)) + (y * y)
end function
public static double code(double x, double y) {
return (((x * x) + (y * y)) + (y * y)) + (y * y);
}
def code(x, y): return (((x * x) + (y * y)) + (y * y)) + (y * y)
function code(x, y) return Float64(Float64(Float64(Float64(x * x) + Float64(y * y)) + Float64(y * y)) + Float64(y * y)) end
function tmp = code(x, y) tmp = (((x * x) + (y * y)) + (y * y)) + (y * y); end
code[x_, y_] := N[(N[(N[(N[(x * x), $MachinePrecision] + N[(y * y), $MachinePrecision]), $MachinePrecision] + N[(y * y), $MachinePrecision]), $MachinePrecision] + N[(y * y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\left(x \cdot x + y \cdot y\right) + y \cdot y\right) + y \cdot y
\end{array}
(FPCore (x y) :precision binary64 (fma (+ y y) y (fma y y (* x x))))
double code(double x, double y) {
return fma((y + y), y, fma(y, y, (x * x)));
}
function code(x, y) return fma(Float64(y + y), y, fma(y, y, Float64(x * x))) end
code[x_, y_] := N[(N[(y + y), $MachinePrecision] * y + N[(y * y + N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(y + y, y, \mathsf{fma}\left(y, y, x \cdot x\right)\right)
\end{array}
Initial program 99.9%
lift-+.f64N/A
lift-+.f64N/A
associate-+l+N/A
+-commutativeN/A
count-2N/A
lift-*.f64N/A
associate-*r*N/A
count-2N/A
lower-fma.f64N/A
lower-+.f64100.0
lift-+.f64N/A
+-commutativeN/A
lift-*.f64N/A
lower-fma.f64100.0
Applied rewrites100.0%
(FPCore (x y) :precision binary64 (if (<= (* x x) 1.3e-135) (fma (+ y y) y (* y y)) (fma (+ y y) y (* x x))))
double code(double x, double y) {
double tmp;
if ((x * x) <= 1.3e-135) {
tmp = fma((y + y), y, (y * y));
} else {
tmp = fma((y + y), y, (x * x));
}
return tmp;
}
function code(x, y) tmp = 0.0 if (Float64(x * x) <= 1.3e-135) tmp = fma(Float64(y + y), y, Float64(y * y)); else tmp = fma(Float64(y + y), y, Float64(x * x)); end return tmp end
code[x_, y_] := If[LessEqual[N[(x * x), $MachinePrecision], 1.3e-135], N[(N[(y + y), $MachinePrecision] * y + N[(y * y), $MachinePrecision]), $MachinePrecision], N[(N[(y + y), $MachinePrecision] * y + N[(x * x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \cdot x \leq 1.3 \cdot 10^{-135}:\\
\;\;\;\;\mathsf{fma}\left(y + y, y, y \cdot y\right)\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(y + y, y, x \cdot x\right)\\
\end{array}
\end{array}
if (*.f64 x x) < 1.30000000000000002e-135Initial program 99.8%
lift-+.f64N/A
lift-+.f64N/A
associate-+l+N/A
+-commutativeN/A
count-2N/A
lift-*.f64N/A
associate-*r*N/A
count-2N/A
lower-fma.f64N/A
lower-+.f6499.9
lift-+.f64N/A
+-commutativeN/A
lift-*.f64N/A
lower-fma.f6499.9
Applied rewrites99.9%
Taylor expanded in y around inf
unpow2N/A
lower-*.f6487.8
Applied rewrites87.8%
if 1.30000000000000002e-135 < (*.f64 x x) Initial program 99.9%
lift-+.f64N/A
lift-+.f64N/A
associate-+l+N/A
+-commutativeN/A
count-2N/A
lift-*.f64N/A
associate-*r*N/A
count-2N/A
lower-fma.f64N/A
lower-+.f64100.0
lift-+.f64N/A
+-commutativeN/A
lift-*.f64N/A
lower-fma.f64100.0
Applied rewrites100.0%
Taylor expanded in y around 0
unpow2N/A
lower-*.f6490.8
Applied rewrites90.8%
(FPCore (x y) :precision binary64 (+ (* x x) (* y (+ y (+ y y)))))
double code(double x, double y) {
return (x * x) + (y * (y + (y + y)));
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (x * x) + (y * (y + (y + y)))
end function
public static double code(double x, double y) {
return (x * x) + (y * (y + (y + y)));
}
def code(x, y): return (x * x) + (y * (y + (y + y)))
function code(x, y) return Float64(Float64(x * x) + Float64(y * Float64(y + Float64(y + y)))) end
function tmp = code(x, y) tmp = (x * x) + (y * (y + (y + y))); end
code[x_, y_] := N[(N[(x * x), $MachinePrecision] + N[(y * N[(y + N[(y + y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot x + y \cdot \left(y + \left(y + y\right)\right)
\end{array}
herbie shell --seed 2024230
(FPCore (x y)
:name "Linear.Quaternion:$c/ from linear-1.19.1.3, E"
:precision binary64
:alt
(! :herbie-platform default (+ (* x x) (* y (+ y (+ y y)))))
(+ (+ (+ (* x x) (* y y)) (* y y)) (* y y)))