
(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 4 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 1.5 x (* -0.5 y)))
double code(double x, double y) {
return fma(1.5, x, (-0.5 * y));
}
function code(x, y) return fma(1.5, x, Float64(-0.5 * y)) end
code[x_, y_] := N[(1.5 * x + N[(-0.5 * y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(1.5, x, -0.5 \cdot y\right)
\end{array}
Initial program 99.9%
Taylor expanded in x around 0
+-commutativeN/A
lower-fma.f64N/A
lower-*.f64100.0
Applied rewrites100.0%
(FPCore (x y) :precision binary64 (if (or (<= x -1.32e-9) (not (<= x 0.051))) (* 1.5 x) (* -0.5 y)))
double code(double x, double y) {
double tmp;
if ((x <= -1.32e-9) || !(x <= 0.051)) {
tmp = 1.5 * x;
} else {
tmp = -0.5 * y;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if ((x <= (-1.32d-9)) .or. (.not. (x <= 0.051d0))) then
tmp = 1.5d0 * x
else
tmp = (-0.5d0) * y
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((x <= -1.32e-9) || !(x <= 0.051)) {
tmp = 1.5 * x;
} else {
tmp = -0.5 * y;
}
return tmp;
}
def code(x, y): tmp = 0 if (x <= -1.32e-9) or not (x <= 0.051): tmp = 1.5 * x else: tmp = -0.5 * y return tmp
function code(x, y) tmp = 0.0 if ((x <= -1.32e-9) || !(x <= 0.051)) tmp = Float64(1.5 * x); else tmp = Float64(-0.5 * y); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((x <= -1.32e-9) || ~((x <= 0.051))) tmp = 1.5 * x; else tmp = -0.5 * y; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[x, -1.32e-9], N[Not[LessEqual[x, 0.051]], $MachinePrecision]], N[(1.5 * x), $MachinePrecision], N[(-0.5 * y), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.32 \cdot 10^{-9} \lor \neg \left(x \leq 0.051\right):\\
\;\;\;\;1.5 \cdot x\\
\mathbf{else}:\\
\;\;\;\;-0.5 \cdot y\\
\end{array}
\end{array}
if x < -1.32e-9 or 0.0509999999999999967 < x Initial program 99.8%
Taylor expanded in x around inf
lower-*.f6476.4
Applied rewrites76.4%
if -1.32e-9 < x < 0.0509999999999999967Initial program 99.9%
Taylor expanded in x around 0
lower-*.f6479.8
Applied rewrites79.8%
Final simplification78.1%
(FPCore (x y) :precision binary64 (fma (- y x) -0.5 x))
double code(double x, double y) {
return fma((y - x), -0.5, x);
}
function code(x, y) return fma(Float64(y - x), -0.5, x) end
code[x_, y_] := N[(N[(y - x), $MachinePrecision] * -0.5 + x), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(y - x, -0.5, x\right)
\end{array}
Initial program 99.9%
lift-+.f64N/A
+-commutativeN/A
lift-/.f64N/A
frac-2negN/A
div-invN/A
lower-fma.f64N/A
neg-sub0N/A
lift--.f64N/A
sub-negN/A
+-commutativeN/A
associate--r+N/A
neg-sub0N/A
remove-double-negN/A
lower--.f64N/A
metadata-evalN/A
metadata-eval99.9
Applied rewrites99.9%
(FPCore (x y) :precision binary64 (* -0.5 y))
double code(double x, double y) {
return -0.5 * y;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (-0.5d0) * y
end function
public static double code(double x, double y) {
return -0.5 * y;
}
def code(x, y): return -0.5 * y
function code(x, y) return Float64(-0.5 * y) end
function tmp = code(x, y) tmp = -0.5 * y; end
code[x_, y_] := N[(-0.5 * y), $MachinePrecision]
\begin{array}{l}
\\
-0.5 \cdot y
\end{array}
Initial program 99.9%
Taylor expanded in x around 0
lower-*.f6453.1
Applied rewrites53.1%
(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 2024318
(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)))