http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55734
--- Comment #20 from Teresa Johnson <tejohnson at google dot com> 2012-12-19 17:07:51 UTC --- On Wed, Dec 19, 2012 at 8:39 AM, jakub at gcc dot gnu.org <gcc-bugzi...@gcc.gnu.org> wrote: > > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55734 > > Jakub Jelinek <jakub at gcc dot gnu.org> changed: > > What |Removed |Added > ---------------------------------------------------------------------------- > CC| |jakub at gcc dot gnu.org > > --- Comment #17 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-12-19 > 16:39:56 UTC --- > I guess a problem of such approach is if not in libgcov.a and HOST_WIDE_INT is > smaller than long long (or for clz even not exactly 64-bit). > For popcount, I wonder why the code uses __builtin_popcountll at all, when the > value is unsigned int, it should just use __builtin_popcount and I think we > can > safely assume that HOST_WIDE_INT is at least as wide as int. > So just using either popcount_hwi or __builtin_popcount (no ll) should be > fine. ok. > For clz, there is: > if (v > 0) > r = 63 - __builtin_clzll (v); > i.e. it relies on clzll having exactly 64-bit argument. For __builtin_clzll > perhaps the assumption is fine, for clz_hwi not so. So you need some extra > code to implement clz_ll on top of clz_hwi if HWI is smaller than 64-bit. ok, thanks for pointing out this issue. I'll try out the solution you posted. Teresa > > -- > Configure bugmail: http://gcc.gnu.org/bugzilla/userprefs.cgi?tab=email > ------- You are receiving this mail because: ------- > You are on the CC list for the bug. -- Teresa Johnson | Software Engineer | tejohn...@google.com | 408-460-2413
