
(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 4 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%
distribute-lft-in100.0%
fma-define100.0%
*-rgt-identity100.0%
Simplified100.0%
Final simplification100.0%
(FPCore (x y) :precision binary64 (if (or (<= y -1.0) (not (<= y 1.0))) (* x y) x))
double code(double x, double y) {
double tmp;
if ((y <= -1.0) || !(y <= 1.0)) {
tmp = x * y;
} else {
tmp = 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)) .or. (.not. (y <= 1.0d0))) then
tmp = x * y
else
tmp = x
end if
code = tmp
end function
public static double code(double x, double y) {
double tmp;
if ((y <= -1.0) || !(y <= 1.0)) {
tmp = x * y;
} else {
tmp = x;
}
return tmp;
}
def code(x, y): tmp = 0 if (y <= -1.0) or not (y <= 1.0): tmp = x * y else: tmp = x return tmp
function code(x, y) tmp = 0.0 if ((y <= -1.0) || !(y <= 1.0)) tmp = Float64(x * y); else tmp = x; end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((y <= -1.0) || ~((y <= 1.0))) tmp = x * y; else tmp = x; end tmp_2 = tmp; end
code[x_, y_] := If[Or[LessEqual[y, -1.0], N[Not[LessEqual[y, 1.0]], $MachinePrecision]], N[(x * y), $MachinePrecision], x]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1 \lor \neg \left(y \leq 1\right):\\
\;\;\;\;x \cdot y\\
\mathbf{else}:\\
\;\;\;\;x\\
\end{array}
\end{array}
if y < -1 or 1 < y Initial program 100.0%
Taylor expanded in y around inf 99.2%
if -1 < y < 1Initial program 100.0%
Taylor expanded in y around 0 97.5%
Final simplification98.4%
(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}
Initial program 100.0%
Final simplification100.0%
(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 51.3%
Final simplification51.3%
(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 2024074
(FPCore (x y)
:name "Data.Colour.RGBSpace.HSL:hsl from colour-2.3.3, B"
:precision binary64
:alt
(+ x (* x y))
(* x (+ y 1.0)))