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From: "izamyatin at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug lto/53787] New: Possible lto improvement
Date: Wed, 27 Jun 2012 17:26:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53787

             Bug #: 53787
           Summary: Possible lto improvement
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: izamyatin@gmail.com


For following Fortan test t.f90 icc can propagate loop counter value and then
perform complete unroll and gcc doesn't do it

      real x(10)
      n = 10
      call init(x,n)
      print *, x
      end

      subroutine init(x, n)
      real x(10)
       do i=1,n
         x(i) = i*i + 1
       enddo

       return
       end

 Not sure it's completely lto problem though...

ifort flags    - -O3 -ipo -inline-level=0
gfortran flags - -O3 -flto -fwhole-program -fno-inline