
(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 (fma y x (- x)))
double code(double x, double y) {
return fma(y, x, -x);
}
function code(x, y) return fma(y, x, Float64(-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%
sub-neg100.0%
*-commutative100.0%
neg-mul-1100.0%
distribute-rgt-out100.0%
Simplified100.0%
distribute-rgt-in100.0%
fma-def100.0%
neg-mul-1100.0%
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (x y) :precision binary64 (if (or (<= y -1.0) (not (<= y 1.0))) (* y x) (- x)))
double code(double x, double y) {
double tmp;
if ((y <= -1.0) || !(y <= 1.0)) {
tmp = y * x;
} 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 = y * x
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 = y * x;
} else {
tmp = -x;
}
return tmp;
}
def code(x, y): tmp = 0 if (y <= -1.0) or not (y <= 1.0): tmp = y * x else: tmp = -x return tmp
function code(x, y) tmp = 0.0 if ((y <= -1.0) || !(y <= 1.0)) tmp = Float64(y * x); else tmp = Float64(-x); end return tmp end
function tmp_2 = code(x, y) tmp = 0.0; if ((y <= -1.0) || ~((y <= 1.0))) tmp = y * x; 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[(y * x), $MachinePrecision], (-x)]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;y \leq -1 \lor \neg \left(y \leq 1\right):\\
\;\;\;\;y \cdot x\\
\mathbf{else}:\\
\;\;\;\;-x\\
\end{array}
\end{array}
if y < -1 or 1 < y Initial program 100.0%
sub-neg100.0%
*-commutative100.0%
neg-mul-1100.0%
distribute-rgt-out100.0%
Simplified100.0%
Taylor expanded in y around inf 98.5%
if -1 < y < 1Initial program 100.0%
sub-neg100.0%
*-commutative100.0%
neg-mul-1100.0%
distribute-rgt-out100.0%
Simplified100.0%
Taylor expanded in y around 0 97.3%
neg-mul-197.3%
Simplified97.3%
Final simplification97.9%
(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]), $MachinePrecision]
\begin{array}{l}
\\
x \cdot \left(y + -1\right)
\end{array}
Initial program 100.0%
sub-neg100.0%
*-commutative100.0%
neg-mul-1100.0%
distribute-rgt-out100.0%
Simplified100.0%
Final simplification100.0%
(FPCore (x y) :precision binary64 (- x))
double code(double x, double y) {
return -x;
}
real(8) function code(x, y)
real(8), intent (in) :: x
real(8), intent (in) :: y
code = -x
end function
public static double code(double x, double y) {
return -x;
}
def code(x, y): return -x
function code(x, y) return Float64(-x) end
function tmp = code(x, y) tmp = -x; end
code[x_, y_] := (-x)
\begin{array}{l}
\\
-x
\end{array}
Initial program 100.0%
sub-neg100.0%
*-commutative100.0%
neg-mul-1100.0%
distribute-rgt-out100.0%
Simplified100.0%
Taylor expanded in y around 0 49.4%
neg-mul-149.4%
Simplified49.4%
Final simplification49.4%
herbie shell --seed 2023331
(FPCore (x y)
:name "Data.Histogram.Bin.LogBinD:$cbinSizeN from histogram-fill-0.8.4.1"
:precision binary64
(- (* x y) x))