
(FPCore (x y) :precision binary64 (* x (+ y 1.0)))
double code(double x, double y) {
return x * (y + 1.0);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x * (y + 1.0d0)
end function
public static double code(double x, double y) {
return x * (y + 1.0);
}
def code(x, y): return x * (y + 1.0)
function code(x, y) return Float64(x * Float64(y + 1.0)) end
function tmp = code(x, y) tmp = x * (y + 1.0); end
code[x_, y_] := N[(x * N[(y + 1.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(y + 1\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 3 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y) :precision binary64 (* x (+ y 1.0)))
double code(double x, double y) {
return x * (y + 1.0);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x * (y + 1.0d0)
end function
public static double code(double x, double y) {
return x * (y + 1.0);
}
def code(x, y): return x * (y + 1.0)
function code(x, y) return Float64(x * Float64(y + 1.0)) end
function tmp = code(x, y) tmp = x * (y + 1.0); end
code[x_, y_] := N[(x * N[(y + 1.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(y + 1\right)
\end{array}
(FPCore (x y) :precision binary64 (fma x y x))
double code(double x, double y) {
return fma(x, y, x);
}
function code(x, y) return fma(x, y, x) end
code[x_, y_] := N[(x * y + x), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(x, y, x\right)
\end{array}
Initial program 100.0%
Taylor expanded in x around 0
+-commutativeN/A
distribute-lft-inN/A
*-rgt-identityN/A
lower-fma.f64100.0
Simplified100.0%
(FPCore (x y) :precision binary64 (if (<= (+ y 1.0) -100000.0) (* x y) (if (<= (+ y 1.0) 2.0) x (* x y))))
double code(double x, double y) {
double tmp;
if ((y + 1.0) <= -100000.0) {
tmp = x * y;
} else if ((y + 1.0) <= 2.0) {
tmp = x;
} else {
tmp = x * y;
}
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) <= (-100000.0d0)) then
tmp = x * y
else if ((y + 1.0d0) <= 2.0d0) then
tmp = x
else
tmp = x * y
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((y + 1.0) <= -100000.0) {
tmp = x * y;
} else if ((y + 1.0) <= 2.0) {
tmp = x;
} else {
tmp = x * y;
}
return tmp;
}
def code(x, y): tmp = 0 if (y + 1.0) <= -100000.0: tmp = x * y elif (y + 1.0) <= 2.0: tmp = x else: tmp = x * y return tmp
function code(x, y) tmp = 0.0 if (Float64(y + 1.0) <= -100000.0) tmp = Float64(x * y); elseif (Float64(y + 1.0) <= 2.0) tmp = x; else tmp = Float64(x * y); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((y + 1.0) <= -100000.0) tmp = x * y; elseif ((y + 1.0) <= 2.0) tmp = x; else tmp = x * y; end tmp_2 = tmp; end
code[x_, y_] := If[LessEqual[N[(y + 1.0), $MachinePrecision], -100000.0], N[(x * y), $MachinePrecision], If[LessEqual[N[(y + 1.0), $MachinePrecision], 2.0], x, N[(x * y), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y + 1 \leq -100000:\\
\;\;\;\;x \cdot y\\
\mathbf{elif}\;y + 1 \leq 2:\\
\;\;\;\;x\\
\mathbf{else}:\\
\;\;\;\;x \cdot y\\
\end{array}
\end{array}
if (+.f64 y #s(literal 1 binary64)) < -1e5 or 2 < (+.f64 y #s(literal 1 binary64)) Initial program 100.0%
Taylor expanded in y around inf
lower-*.f6496.8
Simplified96.8%
if -1e5 < (+.f64 y #s(literal 1 binary64)) < 2Initial program 100.0%
Taylor expanded in y around 0
Simplified97.7%
Final simplification97.2%
(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
Simplified50.9%
Final simplification50.9%
(FPCore (x y) :precision binary64 (+ x (* x y)))
double code(double x, double y) {
return x + (x * y);
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = x + (x * y)
end function
public static double code(double x, double y) {
return x + (x * y);
}
def code(x, y): return x + (x * y)
function code(x, y) return Float64(x + Float64(x * y)) end
function tmp = code(x, y) tmp = x + (x * y); end
code[x_, y_] := N[(x + N[(x * y), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
x + x \cdot y
\end{array}
herbie shell --seed 2024215
(FPCore (x y)
:name "Data.Colour.RGBSpace.HSL:hsl from colour-2.3.3, B"
:precision binary64
:alt
(! :herbie-platform default (+ x (* x y)))
(* x (+ y 1.0)))