
(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 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 (let* ((t_0 (+ (* -0.5 y) x))) (if (<= y -5.7e-62) t_0 (if (<= y 2.1e-14) (* 1.5 x) t_0))))
double code(double x, double y) {
double t_0 = (-0.5 * y) + x;
double tmp;
if (y <= -5.7e-62) {
tmp = t_0;
} else if (y <= 2.1e-14) {
tmp = 1.5 * x;
} else {
tmp = t_0;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: t_0
real(8) :: tmp
t_0 = ((-0.5d0) * y) + x
if (y <= (-5.7d-62)) then
tmp = t_0
else if (y <= 2.1d-14) then
tmp = 1.5d0 * x
else
tmp = t_0
end if
code = tmp
end function
public static double code(double x, double y) {
double t_0 = (-0.5 * y) + x;
double tmp;
if (y <= -5.7e-62) {
tmp = t_0;
} else if (y <= 2.1e-14) {
tmp = 1.5 * x;
} else {
tmp = t_0;
}
return tmp;
}
def code(x, y): t_0 = (-0.5 * y) + x tmp = 0 if y <= -5.7e-62: tmp = t_0 elif y <= 2.1e-14: tmp = 1.5 * x else: tmp = t_0 return tmp
function code(x, y) t_0 = Float64(Float64(-0.5 * y) + x) tmp = 0.0 if (y <= -5.7e-62) tmp = t_0; elseif (y <= 2.1e-14) tmp = Float64(1.5 * x); else tmp = t_0; end return tmp end
function tmp_2 = code(x, y) t_0 = (-0.5 * y) + x; tmp = 0.0; if (y <= -5.7e-62) tmp = t_0; elseif (y <= 2.1e-14) tmp = 1.5 * x; else tmp = t_0; end tmp_2 = tmp; end
code[x_, y_] := Block[{t$95$0 = N[(N[(-0.5 * y), $MachinePrecision] + x), $MachinePrecision]}, If[LessEqual[y, -5.7e-62], t$95$0, If[LessEqual[y, 2.1e-14], N[(1.5 * x), $MachinePrecision], t$95$0]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := -0.5 \cdot y + x\\
\mathbf{if}\;y \leq -5.7 \cdot 10^{-62}:\\
\;\;\;\;t\_0\\
\mathbf{elif}\;y \leq 2.1 \cdot 10^{-14}:\\
\;\;\;\;1.5 \cdot x\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
if y < -5.69999999999999988e-62 or 2.0999999999999999e-14 < y Initial program 100.0%
Taylor expanded in x around 0
lower-*.f6481.6
Applied rewrites81.6%
if -5.69999999999999988e-62 < y < 2.0999999999999999e-14Initial program 99.7%
Taylor expanded in x around inf
lower-*.f6482.4
Applied rewrites82.4%
Final simplification82.0%
(FPCore (x y) :precision binary64 (if (<= y -3.8e-61) (* -0.5 y) (if (<= y 0.0075) (* 1.5 x) (* -0.5 y))))
double code(double x, double y) {
double tmp;
if (y <= -3.8e-61) {
tmp = -0.5 * y;
} else if (y <= 0.0075) {
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 (y <= (-3.8d-61)) then
tmp = (-0.5d0) * y
else if (y <= 0.0075d0) 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 (y <= -3.8e-61) {
tmp = -0.5 * y;
} else if (y <= 0.0075) {
tmp = 1.5 * x;
} else {
tmp = -0.5 * y;
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -3.8e-61: tmp = -0.5 * y elif y <= 0.0075: tmp = 1.5 * x else: tmp = -0.5 * y return tmp
function code(x, y) tmp = 0.0 if (y <= -3.8e-61) tmp = Float64(-0.5 * y); elseif (y <= 0.0075) 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 (y <= -3.8e-61) tmp = -0.5 * y; elseif (y <= 0.0075) tmp = 1.5 * x; else tmp = -0.5 * y; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -3.8e-61], N[(-0.5 * y), $MachinePrecision], If[LessEqual[y, 0.0075], N[(1.5 * x), $MachinePrecision], N[(-0.5 * y), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -3.8 \cdot 10^{-61}:\\
\;\;\;\;-0.5 \cdot y\\
\mathbf{elif}\;y \leq 0.0075:\\
\;\;\;\;1.5 \cdot x\\
\mathbf{else}:\\
\;\;\;\;-0.5 \cdot y\\
\end{array}
\end{array}
if y < -3.7999999999999998e-61 or 0.0074999999999999997 < y Initial program 100.0%
Taylor expanded in x around inf
lower-*.f6422.2
Applied rewrites22.2%
Taylor expanded in x around 0
lower-*.f6478.5
Applied rewrites78.5%
if -3.7999999999999998e-61 < y < 0.0074999999999999997Initial program 99.7%
Taylor expanded in x around inf
lower-*.f6481.9
Applied rewrites81.9%
(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 inf
lower-*.f6449.9
Applied rewrites49.9%
Taylor expanded in x around 0
lower-*.f6451.0
Applied rewrites51.0%
(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 2024294
(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)))