
(FPCore (x y) :precision binary64 (+ x (/ (- x y) 2.0)))
double code(double x, double y) {
return x + ((x - y) / 2.0);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x + ((x - y) / 2.0d0)
end function
public static double code(double x, double y) {
return x + ((x - y) / 2.0);
}
def code(x, y): return x + ((x - y) / 2.0)
function code(x, y) return Float64(x + Float64(Float64(x - y) / 2.0)) end
function tmp = code(x, y) tmp = x + ((x - y) / 2.0); end
code[x_, y_] := N[(x + N[(N[(x - y), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \frac{x - y}{2}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (+ x (/ (- x y) 2.0)))
double code(double x, double y) {
return x + ((x - y) / 2.0);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x + ((x - y) / 2.0d0)
end function
public static double code(double x, double y) {
return x + ((x - y) / 2.0);
}
def code(x, y): return x + ((x - y) / 2.0)
function code(x, y) return Float64(x + Float64(Float64(x - y) / 2.0)) end
function tmp = code(x, y) tmp = x + ((x - y) / 2.0); end
code[x_, y_] := N[(x + N[(N[(x - y), $MachinePrecision] / 2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + \frac{x - y}{2}
\end{array}
(FPCore (x y) :precision binary64 (fma x 1.5 (* y -0.5)))
double code(double x, double y) {
return fma(x, 1.5, (y * -0.5));
}
function code(x, y) return fma(x, 1.5, Float64(y * -0.5)) end
code[x_, y_] := N[(x * 1.5 + N[(y * -0.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(x, 1.5, y \cdot -0.5\right)
\end{array}
Initial program 99.8%
lift-+.f64N/A
+-commutativeN/A
flip-+N/A
lower-/.f64N/A
lower--.f64N/A
lift-/.f64N/A
div-invN/A
associate-*l*N/A
lower-*.f64N/A
lift-/.f64N/A
clear-numN/A
associate-/r/N/A
associate-*r*N/A
lower-*.f64N/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
lower-*.f64N/A
sub-negN/A
Applied rewrites52.7%
Taylor expanded in x around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
lower-*.f64100.0
Applied rewrites100.0%
Final simplification100.0%
(FPCore (x y) :precision binary64 (if (<= x -1900.0) (* x 1.5) (if (<= x 2e-89) (+ x (* y -0.5)) (* x 1.5))))
double code(double x, double y) {
double tmp;
if (x <= -1900.0) {
tmp = x * 1.5;
} else if (x <= 2e-89) {
tmp = x + (y * -0.5);
} else {
tmp = x * 1.5;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (x <= (-1900.0d0)) then
tmp = x * 1.5d0
else if (x <= 2d-89) then
tmp = x + (y * (-0.5d0))
else
tmp = x * 1.5d0
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (x <= -1900.0) {
tmp = x * 1.5;
} else if (x <= 2e-89) {
tmp = x + (y * -0.5);
} else {
tmp = x * 1.5;
}
return tmp;
}
def code(x, y): tmp = 0 if x <= -1900.0: tmp = x * 1.5 elif x <= 2e-89: tmp = x + (y * -0.5) else: tmp = x * 1.5 return tmp
function code(x, y) tmp = 0.0 if (x <= -1900.0) tmp = Float64(x * 1.5); elseif (x <= 2e-89) tmp = Float64(x + Float64(y * -0.5)); else tmp = Float64(x * 1.5); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (x <= -1900.0) tmp = x * 1.5; elseif (x <= 2e-89) tmp = x + (y * -0.5); else tmp = x * 1.5; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[x, -1900.0], N[(x * 1.5), $MachinePrecision], If[LessEqual[x, 2e-89], N[(x + N[(y * -0.5), $MachinePrecision]), $MachinePrecision], N[(x * 1.5), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1900:\\
\;\;\;\;x \cdot 1.5\\
\mathbf{elif}\;x \leq 2 \cdot 10^{-89}:\\
\;\;\;\;x + y \cdot -0.5\\
\mathbf{else}:\\
\;\;\;\;x \cdot 1.5\\
\end{array}
\end{array}
if x < -1900 or 2.00000000000000008e-89 < x Initial program 99.8%
Taylor expanded in x around inf
*-commutativeN/A
lower-*.f6470.6
Applied rewrites70.6%
if -1900 < x < 2.00000000000000008e-89Initial program 99.9%
Taylor expanded in x around 0
lower-*.f6481.5
Applied rewrites81.5%
Final simplification75.2%
(FPCore (x y) :precision binary64 (- (* 1.5 x) (* 0.5 y)))
double code(double x, double y) {
return (1.5 * x) - (0.5 * y);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (1.5d0 * x) - (0.5d0 * y)
end function
public static double code(double x, double y) {
return (1.5 * x) - (0.5 * y);
}
def code(x, y): return (1.5 * x) - (0.5 * y)
function code(x, y) return Float64(Float64(1.5 * x) - Float64(0.5 * y)) end
function tmp = code(x, y) tmp = (1.5 * x) - (0.5 * y); end
code[x_, y_] := N[(N[(1.5 * x), $MachinePrecision] - N[(0.5 * y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
1.5 \cdot x - 0.5 \cdot y
\end{array}
herbie shell --seed 2024228
(FPCore (x y)
:name "Graphics.Rendering.Chart.Axis.Types:hBufferRect from Chart-1.5.3"
:precision binary64
:alt
(! :herbie-platform default (- (* 3/2 x) (* 1/2 y)))
(+ x (/ (- x y) 2.0)))