Am 01.03.2020 um 07:33 schrieb Takashi Yano:
However, from the view point of performance, just inline
static function is better.
I don't see how that could be the case. Inline methods of a static C++
object should not suffer any perfomance penalty compared to inline
functions operating on static variables.
Attached code measures the
performance of access speed for wpbuf.
I compiled it by g++ 7.4.0 with -O2 option.
The result is as follows.
Total1: 2.315627 second
Total2: 1.588511 second
Total3: 1.571572 second
Strange. The result here (with GCC 9.2) is rather different:
$ g++ -O2 -o tt wpbuf-bench.cc && ./tt
Total1: 0.753815 second
Total2: 0.757444 second
Total3: 1.217352 second
And on inspection, all three bench*() functions do appear to have
exactly the same machine code, too. They may be inlined and mixed into
main() somewhat differently, though. That might explain the difference
more readily than any actual difference in speed between the three
implementations.
