[Bug fortran/53950] New: 1.5 times slowdown from 4.4.0 to 4.7.0

[kapojko at yahoo dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53950

             Bug #: 53950
           Summary: 1.5 times slowdown from 4.4.0 to 4.7.0
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: kapojko@yahoo.com


Created attachment 27784
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27784
Demonstration of slowdown

I'm using MinGW GCC 4.4.0 to work with C/C++/Fortran project. Some days ago
I've downloaded web installer and switched to GCC 4.7.0. Unfortunately I
noticed a dramatic performance regression.

I attach a minimal program that demonstrates the slowdown to the ticket.

Compiled with "gfortran -o test_self.exe -O3 test_self.f90" I get on my Core
i7:
  GCC 4.4.0:     Time of operation was    1.2012070      seconds
  GCC 4.7.0:     Time of operation was    1.85641098      seconds


Yury Kapoyko, Russia