
(FPCore (a b) :precision binary64 (- (* a a) (* b b)))
double code(double a, double b) {
return (a * a) - (b * b);
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = (a * a) - (b * b)
end function
public static double code(double a, double b) {
return (a * a) - (b * b);
}
def code(a, b): return (a * a) - (b * b)
function code(a, b) return Float64(Float64(a * a) - Float64(b * b)) end
function tmp = code(a, b) tmp = (a * a) - (b * b); end
code[a_, b_] := N[(N[(a * a), $MachinePrecision] - N[(b * b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
a \cdot a - b \cdot b
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b) :precision binary64 (- (* a a) (* b b)))
double code(double a, double b) {
return (a * a) - (b * b);
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = (a * a) - (b * b)
end function
public static double code(double a, double b) {
return (a * a) - (b * b);
}
def code(a, b): return (a * a) - (b * b)
function code(a, b) return Float64(Float64(a * a) - Float64(b * b)) end
function tmp = code(a, b) tmp = (a * a) - (b * b); end
code[a_, b_] := N[(N[(a * a), $MachinePrecision] - N[(b * b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
a \cdot a - b \cdot b
\end{array}
a_m = (fabs.f64 a) b_m = (fabs.f64 b) (FPCore (a_m b_m) :precision binary64 (if (<= (* a_m a_m) 3e+289) (fma a_m a_m (* b_m (- b_m))) (* a_m (+ a_m (* b_m -2.0)))))
a_m = fabs(a);
b_m = fabs(b);
double code(double a_m, double b_m) {
double tmp;
if ((a_m * a_m) <= 3e+289) {
tmp = fma(a_m, a_m, (b_m * -b_m));
} else {
tmp = a_m * (a_m + (b_m * -2.0));
}
return tmp;
}
a_m = abs(a) b_m = abs(b) function code(a_m, b_m) tmp = 0.0 if (Float64(a_m * a_m) <= 3e+289) tmp = fma(a_m, a_m, Float64(b_m * Float64(-b_m))); else tmp = Float64(a_m * Float64(a_m + Float64(b_m * -2.0))); end return tmp end
a_m = N[Abs[a], $MachinePrecision] b_m = N[Abs[b], $MachinePrecision] code[a$95$m_, b$95$m_] := If[LessEqual[N[(a$95$m * a$95$m), $MachinePrecision], 3e+289], N[(a$95$m * a$95$m + N[(b$95$m * (-b$95$m)), $MachinePrecision]), $MachinePrecision], N[(a$95$m * N[(a$95$m + N[(b$95$m * -2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
a_m = \left|a\right|
\\
b_m = \left|b\right|
\\
\begin{array}{l}
\mathbf{if}\;a_m \cdot a_m \leq 3 \cdot 10^{+289}:\\
\;\;\;\;\mathsf{fma}\left(a_m, a_m, b_m \cdot \left(-b_m\right)\right)\\
\mathbf{else}:\\
\;\;\;\;a_m \cdot \left(a_m + b_m \cdot -2\right)\\
\end{array}
\end{array}
if (*.f64 a a) < 3.0000000000000002e289Initial program 100.0%
sqr-neg100.0%
cancel-sign-sub100.0%
fma-def100.0%
Simplified100.0%
if 3.0000000000000002e289 < (*.f64 a a) Initial program 78.6%
difference-of-squares100.0%
add-sqr-sqrt40.0%
sqrt-prod91.4%
sqr-neg91.4%
sqrt-unprod54.3%
add-sqr-sqrt90.0%
sub-neg90.0%
pow190.0%
pow190.0%
pow-prod-up90.0%
add-sqr-sqrt48.6%
add-sqr-sqrt17.1%
difference-of-squares17.1%
metadata-eval17.1%
unpow-prod-down17.1%
Applied egg-rr17.1%
unpow217.1%
unpow217.1%
unswap-sqr17.1%
difference-of-squares17.1%
unpow1/217.1%
unpow1/217.1%
pow-sqr17.1%
metadata-eval17.1%
unpow117.1%
unpow1/217.1%
unpow1/217.1%
pow-sqr17.1%
metadata-eval17.1%
unpow117.1%
difference-of-squares17.1%
unpow1/217.1%
unpow1/217.1%
pow-sqr35.7%
metadata-eval35.7%
unpow135.7%
Simplified90.0%
Taylor expanded in a around inf 78.6%
*-commutative78.6%
associate-*l*78.6%
unpow278.6%
distribute-lft-out97.1%
Simplified97.1%
Final simplification99.2%
a_m = (fabs.f64 a) b_m = (fabs.f64 b) (FPCore (a_m b_m) :precision binary64 (if (<= (* a_m a_m) 3e+289) (- (* a_m a_m) (* b_m b_m)) (* a_m (+ a_m (* b_m -2.0)))))
a_m = fabs(a);
b_m = fabs(b);
double code(double a_m, double b_m) {
double tmp;
if ((a_m * a_m) <= 3e+289) {
tmp = (a_m * a_m) - (b_m * b_m);
} else {
tmp = a_m * (a_m + (b_m * -2.0));
}
return tmp;
}
a_m = abs(a)
b_m = abs(b)
real(8) function code(a_m, b_m)
real(8), intent (in) :: a_m
real(8), intent (in) :: b_m
real(8) :: tmp
if ((a_m * a_m) <= 3d+289) then
tmp = (a_m * a_m) - (b_m * b_m)
else
tmp = a_m * (a_m + (b_m * (-2.0d0)))
end if
code = tmp
end function
a_m = Math.abs(a);
b_m = Math.abs(b);
public static double code(double a_m, double b_m) {
double tmp;
if ((a_m * a_m) <= 3e+289) {
tmp = (a_m * a_m) - (b_m * b_m);
} else {
tmp = a_m * (a_m + (b_m * -2.0));
}
return tmp;
}
a_m = math.fabs(a) b_m = math.fabs(b) def code(a_m, b_m): tmp = 0 if (a_m * a_m) <= 3e+289: tmp = (a_m * a_m) - (b_m * b_m) else: tmp = a_m * (a_m + (b_m * -2.0)) return tmp
a_m = abs(a) b_m = abs(b) function code(a_m, b_m) tmp = 0.0 if (Float64(a_m * a_m) <= 3e+289) tmp = Float64(Float64(a_m * a_m) - Float64(b_m * b_m)); else tmp = Float64(a_m * Float64(a_m + Float64(b_m * -2.0))); end return tmp end
a_m = abs(a); b_m = abs(b); function tmp_2 = code(a_m, b_m) tmp = 0.0; if ((a_m * a_m) <= 3e+289) tmp = (a_m * a_m) - (b_m * b_m); else tmp = a_m * (a_m + (b_m * -2.0)); end tmp_2 = tmp; end
a_m = N[Abs[a], $MachinePrecision] b_m = N[Abs[b], $MachinePrecision] code[a$95$m_, b$95$m_] := If[LessEqual[N[(a$95$m * a$95$m), $MachinePrecision], 3e+289], N[(N[(a$95$m * a$95$m), $MachinePrecision] - N[(b$95$m * b$95$m), $MachinePrecision]), $MachinePrecision], N[(a$95$m * N[(a$95$m + N[(b$95$m * -2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
a_m = \left|a\right|
\\
b_m = \left|b\right|
\\
\begin{array}{l}
\mathbf{if}\;a_m \cdot a_m \leq 3 \cdot 10^{+289}:\\
\;\;\;\;a_m \cdot a_m - b_m \cdot b_m\\
\mathbf{else}:\\
\;\;\;\;a_m \cdot \left(a_m + b_m \cdot -2\right)\\
\end{array}
\end{array}
if (*.f64 a a) < 3.0000000000000002e289Initial program 100.0%
if 3.0000000000000002e289 < (*.f64 a a) Initial program 78.6%
difference-of-squares100.0%
add-sqr-sqrt40.0%
sqrt-prod91.4%
sqr-neg91.4%
sqrt-unprod54.3%
add-sqr-sqrt90.0%
sub-neg90.0%
pow190.0%
pow190.0%
pow-prod-up90.0%
add-sqr-sqrt48.6%
add-sqr-sqrt17.1%
difference-of-squares17.1%
metadata-eval17.1%
unpow-prod-down17.1%
Applied egg-rr17.1%
unpow217.1%
unpow217.1%
unswap-sqr17.1%
difference-of-squares17.1%
unpow1/217.1%
unpow1/217.1%
pow-sqr17.1%
metadata-eval17.1%
unpow117.1%
unpow1/217.1%
unpow1/217.1%
pow-sqr17.1%
metadata-eval17.1%
unpow117.1%
difference-of-squares17.1%
unpow1/217.1%
unpow1/217.1%
pow-sqr35.7%
metadata-eval35.7%
unpow135.7%
Simplified90.0%
Taylor expanded in a around inf 78.6%
*-commutative78.6%
associate-*l*78.6%
unpow278.6%
distribute-lft-out97.1%
Simplified97.1%
Final simplification99.2%
a_m = (fabs.f64 a) b_m = (fabs.f64 b) (FPCore (a_m b_m) :precision binary64 (* a_m (+ a_m (* b_m -2.0))))
a_m = fabs(a);
b_m = fabs(b);
double code(double a_m, double b_m) {
return a_m * (a_m + (b_m * -2.0));
}
a_m = abs(a)
b_m = abs(b)
real(8) function code(a_m, b_m)
real(8), intent (in) :: a_m
real(8), intent (in) :: b_m
code = a_m * (a_m + (b_m * (-2.0d0)))
end function
a_m = Math.abs(a);
b_m = Math.abs(b);
public static double code(double a_m, double b_m) {
return a_m * (a_m + (b_m * -2.0));
}
a_m = math.fabs(a) b_m = math.fabs(b) def code(a_m, b_m): return a_m * (a_m + (b_m * -2.0))
a_m = abs(a) b_m = abs(b) function code(a_m, b_m) return Float64(a_m * Float64(a_m + Float64(b_m * -2.0))) end
a_m = abs(a); b_m = abs(b); function tmp = code(a_m, b_m) tmp = a_m * (a_m + (b_m * -2.0)); end
a_m = N[Abs[a], $MachinePrecision] b_m = N[Abs[b], $MachinePrecision] code[a$95$m_, b$95$m_] := N[(a$95$m * N[(a$95$m + N[(b$95$m * -2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
a_m = \left|a\right|
\\
b_m = \left|b\right|
\\
a_m \cdot \left(a_m + b_m \cdot -2\right)
\end{array}
Initial program 94.1%
difference-of-squares100.0%
add-sqr-sqrt48.4%
sqrt-prod76.6%
sqr-neg76.6%
sqrt-unprod28.9%
add-sqr-sqrt52.1%
sub-neg52.1%
pow152.1%
pow152.1%
pow-prod-up52.1%
add-sqr-sqrt27.6%
add-sqr-sqrt12.1%
difference-of-squares12.1%
metadata-eval12.1%
unpow-prod-down12.1%
Applied egg-rr12.1%
unpow212.1%
unpow212.1%
unswap-sqr12.1%
difference-of-squares12.1%
unpow1/212.1%
unpow1/212.1%
pow-sqr12.1%
metadata-eval12.1%
unpow112.1%
unpow1/212.1%
unpow1/212.1%
pow-sqr12.1%
metadata-eval12.1%
unpow112.1%
difference-of-squares12.1%
unpow1/212.1%
unpow1/212.1%
pow-sqr23.2%
metadata-eval23.2%
unpow123.2%
Simplified52.1%
Taylor expanded in a around inf 50.9%
*-commutative50.9%
associate-*l*50.9%
unpow250.9%
distribute-lft-out55.9%
Simplified55.9%
Final simplification55.9%
a_m = (fabs.f64 a) b_m = (fabs.f64 b) (FPCore (a_m b_m) :precision binary64 (* b_m (* a_m -2.0)))
a_m = fabs(a);
b_m = fabs(b);
double code(double a_m, double b_m) {
return b_m * (a_m * -2.0);
}
a_m = abs(a)
b_m = abs(b)
real(8) function code(a_m, b_m)
real(8), intent (in) :: a_m
real(8), intent (in) :: b_m
code = b_m * (a_m * (-2.0d0))
end function
a_m = Math.abs(a);
b_m = Math.abs(b);
public static double code(double a_m, double b_m) {
return b_m * (a_m * -2.0);
}
a_m = math.fabs(a) b_m = math.fabs(b) def code(a_m, b_m): return b_m * (a_m * -2.0)
a_m = abs(a) b_m = abs(b) function code(a_m, b_m) return Float64(b_m * Float64(a_m * -2.0)) end
a_m = abs(a); b_m = abs(b); function tmp = code(a_m, b_m) tmp = b_m * (a_m * -2.0); end
a_m = N[Abs[a], $MachinePrecision] b_m = N[Abs[b], $MachinePrecision] code[a$95$m_, b$95$m_] := N[(b$95$m * N[(a$95$m * -2.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
a_m = \left|a\right|
\\
b_m = \left|b\right|
\\
b_m \cdot \left(a_m \cdot -2\right)
\end{array}
Initial program 94.1%
difference-of-squares100.0%
add-sqr-sqrt48.4%
sqrt-prod76.6%
sqr-neg76.6%
sqrt-unprod28.9%
add-sqr-sqrt52.1%
sub-neg52.1%
pow152.1%
pow152.1%
pow-prod-up52.1%
add-sqr-sqrt27.6%
add-sqr-sqrt12.1%
difference-of-squares12.1%
metadata-eval12.1%
unpow-prod-down12.1%
Applied egg-rr12.1%
unpow212.1%
unpow212.1%
unswap-sqr12.1%
difference-of-squares12.1%
unpow1/212.1%
unpow1/212.1%
pow-sqr12.1%
metadata-eval12.1%
unpow112.1%
unpow1/212.1%
unpow1/212.1%
pow-sqr12.1%
metadata-eval12.1%
unpow112.1%
difference-of-squares12.1%
unpow1/212.1%
unpow1/212.1%
pow-sqr23.2%
metadata-eval23.2%
unpow123.2%
Simplified52.1%
Taylor expanded in a around inf 50.9%
*-commutative50.9%
associate-*l*50.9%
unpow250.9%
distribute-lft-out55.9%
Simplified55.9%
Taylor expanded in a around 0 15.6%
associate-*r*15.6%
*-commutative15.6%
Simplified15.6%
Final simplification15.6%
(FPCore (a b) :precision binary64 (* (+ a b) (- a b)))
double code(double a, double b) {
return (a + b) * (a - b);
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = (a + b) * (a - b)
end function
public static double code(double a, double b) {
return (a + b) * (a - b);
}
def code(a, b): return (a + b) * (a - b)
function code(a, b) return Float64(Float64(a + b) * Float64(a - b)) end
function tmp = code(a, b) tmp = (a + b) * (a - b); end
code[a_, b_] := N[(N[(a + b), $MachinePrecision] * N[(a - b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(a + b\right) \cdot \left(a - b\right)
\end{array}
herbie shell --seed 2024024
(FPCore (a b)
:name "Difference of squares"
:precision binary64
:herbie-target
(* (+ a b) (- a b))
(- (* a a) (* b b)))