
(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 y x x))
double code(double x, double y) {
return fma(y, x, x);
}
function code(x, y) return fma(y, x, x) end
code[x_, y_] := N[(y * x + x), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(y, x, x\right)
\end{array}
Initial program 100.0%
lift-*.f64N/A
lift-+.f64N/A
distribute-rgt-inN/A
*-lft-identityN/A
lower-fma.f64100.0
Applied rewrites100.0%
(FPCore (x y) :precision binary64 (if (or (<= (+ y 1.0) -20000000.0) (not (<= (+ y 1.0) 2.0))) (* y x) (* x 1.0)))
double code(double x, double y) {
double tmp;
if (((y + 1.0) <= -20000000.0) || !((y + 1.0) <= 2.0)) {
tmp = y * x;
} else {
tmp = x * 1.0;
}
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) <= (-20000000.0d0)) .or. (.not. ((y + 1.0d0) <= 2.0d0))) then
tmp = y * x
else
tmp = x * 1.0d0
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if (((y + 1.0) <= -20000000.0) || !((y + 1.0) <= 2.0)) {
tmp = y * x;
} else {
tmp = x * 1.0;
}
return tmp;
}
def code(x, y): tmp = 0 if ((y + 1.0) <= -20000000.0) or not ((y + 1.0) <= 2.0): tmp = y * x else: tmp = x * 1.0 return tmp
function code(x, y) tmp = 0.0 if ((Float64(y + 1.0) <= -20000000.0) || !(Float64(y + 1.0) <= 2.0)) tmp = Float64(y * x); else tmp = Float64(x * 1.0); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if (((y + 1.0) <= -20000000.0) || ~(((y + 1.0) <= 2.0))) tmp = y * x; else tmp = x * 1.0; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[N[(y + 1.0), $MachinePrecision], -20000000.0], N[Not[LessEqual[N[(y + 1.0), $MachinePrecision], 2.0]], $MachinePrecision]], N[(y * x), $MachinePrecision], N[(x * 1.0), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y + 1 \leq -20000000 \lor \neg \left(y + 1 \leq 2\right):\\
\;\;\;\;y \cdot x\\
\mathbf{else}:\\
\;\;\;\;x \cdot 1\\
\end{array}
\end{array}
if (+.f64 y #s(literal 1 binary64)) < -2e7 or 2 < (+.f64 y #s(literal 1 binary64)) Initial program 100.0%
Taylor expanded in y around inf
*-commutativeN/A
lower-*.f6498.7
Applied rewrites98.7%
if -2e7 < (+.f64 y #s(literal 1 binary64)) < 2Initial program 100.0%
Taylor expanded in y around 0
Applied rewrites96.3%
Final simplification97.6%
(FPCore (x y) :precision binary64 (* y x))
double code(double x, double y) {
return y * x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = y * x
end function
public static double code(double x, double y) {
return y * x;
}
def code(x, y): return y * x
function code(x, y) return Float64(y * x) end
function tmp = code(x, y) tmp = y * x; end
code[x_, y_] := N[(y * x), $MachinePrecision]
\begin{array}{l}
\\
y \cdot x
\end{array}
Initial program 100.0%
Taylor expanded in y around inf
*-commutativeN/A
lower-*.f6456.5
Applied rewrites56.5%
(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 2024307
(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)))