[Bug middle-end/54114] New: variable-tracking performance regression from 4.8-20120610 to 4.8-20120701

[jimis at gmx dot net]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54114

             Bug #: 54114
           Summary: variable-tracking performance regression from
                    4.8-20120610 to 4.8-20120701
    Classification: Unclassified
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: jimis@gmx.net


Compiling the XPath.cpp from xalanc shows significant performance regression
because of variable tracking, between GCC 4.8-20120610 to 4.8-20120701.
Tracking it down is hard since var-tracking.c changed a lot in the past month,
CC'ing lxo for better ideas. :-)

It seems to apply mostly to C++ code, see the graph and the last annotation at
http://teras-ics.mooo.com:8003/