On Wed, Nov 05, 2014 at 04:47:14PM +0100, Maxime Coquelin wrote: > > On 11/05/2014 12:10 PM, Rasmus Villemoes wrote: > >On Tue, Nov 04 2014, Maxime COQUELIN <maxime.coque...@st.com> wrote: > > > >>-#define GENMASK(h, l) (((U32_C(1) << ((h) - (l) + 1)) - 1) << > >>(l)) > >>-#define GENMASK_ULL(h, l) (((U64_C(1) << ((h) - (l) + 1)) - 1) << (l)) > >>+#define GENMASK(h, l) \ > >>+ ((~0UL >> (BITS_PER_LONG - ((h) - (l) + 1))) << (l)) > >>+ > >>+#define GENMASK_ULL(h, l) \ > >>+ ((~0ULL >> (BITS_PER_LONG_LONG - ((h) - (l) + 1))) << (l)) > >Slightly bikeshedding here, but may I suggest spelling it > > > > (((~0UL) << (l)) & (~0UL >> (BITS_PER_LONG - 1 - (h)))) > > > >? This will ensure the arguments are expanded once each, and will, IMHO, > >DTRT if/when l > h (namely, yield 0). > That's a good point. > > Peter, what is your view?
I'm fine with that, feel free to post another version and I'll replace v3. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
