Re: About g++ optimization

[address@hidden]

Allan Wind wrote:
> On 2006-03-30T12:30:30-0800, PengYu.UT@gmail.com wrote:
> > for(int i = 0; i < f(n); ++ i) {
> > ...
> > }
>
> Make sure you remove the space between ++ and i.

Why I have to remove the space? Is it well accepted coding convention?

>
> > If I have the above "for" statement and I compile it with -O3, will the
> > function "f(n)" be optimized such that f(n) will only be evaluated
> > once. Or I have to factor "f(n)" outside the loop to make sure that it
> > only be evaluated once?
>
> If you compile you example with -S then the assembler file (.s) will
> tell you.
>
>
> /Allan
>
> --Dxnq1zWXvFF0Q93v
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