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Mario Domenech Goulart wrote:
> There's an interesting discussion in the OpenBSD mailing
> list about the use of inline.
There is no such thing as "best optimization". Some optimization
techniques tend to show better performance on the average, but given a
specific code, the same technique can fail dramatically.
Inlining makes the code faster if the called function is small
(preferably smaller than a cache-line), and called only a few times. No
inlining will result in faster code if the function is large (at least
one complete cache-line is used), and that function has a good chance to
be already in the cache when called.
Also inlined functions allow the block-reordering code to do interesting
things. Block-reordering was introduced in gcc3, BSDs are using
gcc-2.95, AFAIK.
So far the facts.
Now the manual says that for gcc the inline-limit is 600 bytes, compared
to the 32-128 byte cache line size of the x86 CPUs. It could be worth to
try lower numbers with inline-functions...
/Ervin
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