On 12 Mar 2006 18:09:26 +0100, Gabriel Dos Reis
<[EMAIL PROTECTED]> wrote:
> "Richard Guenther" <[EMAIL PROTECTED]> writes:
>
> [...]
>
> | this one should be measured. But note that the benchmark is a
> | no-op and can be validly optimizes to int main() { return 0; } by the
> | compiler. This is why I call it a stupid benchmark.
>
> please let's refrain from getting into that back hole.
>
> Different people measure different things that they perceive important
> for them. I doubt that the "optimization to int main() { return 0; }"
> would be useful to everybody.
>
> | Also you are measuring exclusively cache performance.
>
> that may be a decisive criteria under given circumstances; it takes
> more justification to qualify it as "stupid benchmark". We can either
> acknowledge "oops, we fumbled that case; but we are not going to fix
> it" or "well, we should not have done that; it should be fixed".
> But handwaving with "stupid" qualification is not helpful.
So, I tried to reproduce the slowdown and on i686 get all
memcpy/memset inlined on 3.3, 3.4, 4.0 and 4.1. On ppc I get calls to
memcpy/memset in all cases. This might be more a glibc issue I think.
Richard.
