[Bug tree-optimization/52171] New: memcmp/strcmp/strncmp can be optimized when the result is tested for [in]equality with 0

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52171

             Bug #: 52171
           Summary: memcmp/strcmp/strncmp can be optimized when the result
                    is tested for [in]equality with 0
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: rgue...@gcc.gnu.org
            Blocks: 43052


On GIMPLE we should expand memcmp/strcmp/strncmp to inline integral compares
if the result is only tested against equality with 0.

See PR43052 where we hint at that these may be the only profitable cases
to inline for memcmp at least.