[Bug rtl-optimization/18992] New: delete_trivially_dead_insns made ineffective for two-address targets

["amylaar at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

delete_trivially_dead_insns is no longer able to remove sequences
where the same register is first set and then modifed in a sequence of
instructions to compute a particular value, as it is common on two-address
machines.  This affects both the 3.4 series and 4.0 .  Details of the
problem and a patch are here:

http://gcc.gnu.org/ml/gcc-patches/2004-05/msg01037.html

-- 
           Summary: delete_trivially_dead_insns made ineffective for two-
                    address targets
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: rtl-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: amylaar at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18992