[Bug other/21812] New: libgcc could use some target specific optimizations

["nmiell at comcast dot net" <gcc-bugzilla at gcc dot gnu dot org>]

libgcc is currently contains pure C functions with simple (i.e. non-optimal
implementations). Allowing individual targets to provide their own versions of
the functions could boost performance.

i.e. comparing the libgcc C implementation of __popcountdi2 to the assembly
version provided in the Opteron optimization manual, we find that the AMD
supplied version is half the instructions, branchless, uses no data tables (and
thus causes no cache misses), and runs in about 1/3 to 1/2 less time.

-- 
           Summary: libgcc could use some target specific optimizations
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: other
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: nmiell at comcast dot net
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21812