RE: [PATCH 4/6] arm64/io: Provide a WC friendly __iowriteXX_copy()

David Laight
2024-02-23T11:05:35Z

...
> > > > > + if ((_count % 8) >= 4) {
> > > >
> > > > If (_count & 4) {
> > >
> > > That would be obfuscating, IMHO. The compiler doesn't need such things
> > > to generate optimal code.
> >
> > Try it: https://godbolt.org/z/EvvGrTxv3
> > And it isn't that obfuscated - no more so than your version.
>
> The godbolt link does "n % 8 > 4" instead of "... >= 4" as in Jason's
> original code. With ">=" the compiled code matches that for "n & 4".

Bugger :-)

David

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