2015-03-05 12:57+0800, Dongsheng Song: > On Wed, Mar 4, 2015 at 10:30 PM, Gerd Hoffmann <kra...@redhat.com> wrote: > > +/* round up to the nearest power of 2 (0 if overflow) */ > > +uint64_t pow2ceil(uint64_t value) > > +{ > > + uint8_t nlz = clz64(value); > > + > > + if (is_power_of_2(value)) { > > + return value; > > + } > > please call clz64 after is_power_of_2.
All callers under clz64() are inline, so the optimizer can see that there are no side effects and move the code if it would be faster; I thought that separating it would only make the code uglier, because QEMU doesn't allow lazy declarations ... Markus had another design issue with this patch, so I'll send a v2 after reaching the conclusion there. Thanks.