
(FPCore (x y) :precision binary64 (- (* x y) x))
double code(double x, double y) {
return (x * y) - x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (x * y) - x
end function
public static double code(double x, double y) {
return (x * y) - x;
}
def code(x, y): return (x * y) - x
function code(x, y) return Float64(Float64(x * y) - x) end
function tmp = code(x, y) tmp = (x * y) - x; end
code[x_, y_] := N[(N[(x * y), $MachinePrecision] - x), $MachinePrecision]
\begin{array}{l}
\\
x \cdot y - x
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (- (* x y) x))
double code(double x, double y) {
return (x * y) - x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (x * y) - x
end function
public static double code(double x, double y) {
return (x * y) - x;
}
def code(x, y): return (x * y) - x
function code(x, y) return Float64(Float64(x * y) - x) end
function tmp = code(x, y) tmp = (x * y) - x; end
code[x_, y_] := N[(N[(x * y), $MachinePrecision] - x), $MachinePrecision]
\begin{array}{l}
\\
x \cdot y - x
\end{array}
(FPCore (x y) :precision binary64 (- (* y x) x))
double code(double x, double y) {
return (y * x) - x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = (y * x) - x
end function
public static double code(double x, double y) {
return (y * x) - x;
}
def code(x, y): return (y * x) - x
function code(x, y) return Float64(Float64(y * x) - x) end
function tmp = code(x, y) tmp = (y * x) - x; end
code[x_, y_] := N[(N[(y * x), $MachinePrecision] - x), $MachinePrecision]
\begin{array}{l}
\\
y \cdot x - x
\end{array}
Initial program 100.0%
Final simplification100.0%
(FPCore (x y) :precision binary64 (if (<= y -1.0) (* y x) (if (<= y 1.0) (- x) (* y x))))
double code(double x, double y) {
double tmp;
if (y <= -1.0) {
tmp = y * x;
} else if (y <= 1.0) {
tmp = -x;
} else {
tmp = y * x;
}
return tmp;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8) :: tmp
if (y <= (-1.0d0)) then
tmp = y * x
else if (y <= 1.0d0) then
tmp = -x
else
tmp = y * x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (y <= -1.0) {
tmp = y * x;
} else if (y <= 1.0) {
tmp = -x;
} else {
tmp = y * x;
}
return tmp;
}
def code(x, y): tmp = 0 if y <= -1.0: tmp = y * x elif y <= 1.0: tmp = -x else: tmp = y * x return tmp
function code(x, y) tmp = 0.0 if (y <= -1.0) tmp = Float64(y * x); elseif (y <= 1.0) tmp = Float64(-x); else tmp = Float64(y * x); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (y <= -1.0) tmp = y * x; elseif (y <= 1.0) tmp = -x; else tmp = y * x; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[y, -1.0], N[(y * x), $MachinePrecision], If[LessEqual[y, 1.0], (-x), N[(y * x), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1:\\
\;\;\;\;y \cdot x\\
\mathbf{elif}\;y \leq 1:\\
\;\;\;\;-x\\
\mathbf{else}:\\
\;\;\;\;y \cdot x\\
\end{array}
\end{array}
if y < -1 or 1 < y Initial program 100.0%
Taylor expanded in y around inf
*-commutativeN/A
lower-*.f6498.7
Applied rewrites98.7%
if -1 < y < 1Initial program 100.0%
Taylor expanded in y around 0
mul-1-negN/A
lower-neg.f6498.6
Applied rewrites98.6%
(FPCore (x y) :precision binary64 (- x))
double code(double x, double y) {
return -x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = -x
end function
public static double code(double x, double y) {
return -x;
}
def code(x, y): return -x
function code(x, y) return Float64(-x) end
function tmp = code(x, y) tmp = -x; end
code[x_, y_] := (-x)
\begin{array}{l}
\\
-x
\end{array}
Initial program 100.0%
Taylor expanded in y around 0
mul-1-negN/A
lower-neg.f6448.1
Applied rewrites48.1%
(FPCore (x y) :precision binary64 x)
double code(double x, double y) {
return x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x
end function
public static double code(double x, double y) {
return x;
}
def code(x, y): return x
function code(x, y) return x end
function tmp = code(x, y) tmp = x; end
code[x_, y_] := x
\begin{array}{l}
\\
x
\end{array}
Initial program 100.0%
Taylor expanded in y around 0
mul-1-negN/A
lower-neg.f6448.1
Applied rewrites48.1%
Applied rewrites2.8%
herbie shell --seed 2024257
(FPCore (x y)
:name "Data.Histogram.Bin.LogBinD:$cbinSizeN from histogram-fill-0.8.4.1"
:precision binary64
(- (* x y) x))