Please see individual files for details of the license on each file.
The preferred license can be found in LICENSE.

All files in this distribution (other than in the ext directory) have
licenses based on the BSD or MIT licenses.  Some files in the ext
directory are GNU LGPL.  No other licenses are found in this
distribution.

Beyond the BSD license, some files include the following clarification
of the license as required by the copyright holder:

    The license below extends only to copyright in the software and
    shall not be construed as granting a license to any other
    intellectual property including but not limited to intellectual
    property relating to a hardware implementation of the
    functionality of the software licensed hereunder.  You may use the
    software subject to the license terms below provided that you
    ensure that this notice is replicated unmodified and in its
    entirety in all distributions of the software, modified or
    unmodified, in source code or in binary form.

The copyright holders include (not counting the ext directory):

Copyright (c) 2000-2011 The Regents of The University of Michigan
Copyright (c) 1990,1993-1995,2007-2010 The Hewlett-Packard Development Company
Copyright (c) 1999-2009,2011 Mark D. Hill and David A. Wood
Copyright (c) 2009-2011 ARM Limited
Copyright (c) 2008-2009 Princeton University
Copyright (c) 2007 MIPS Technologies, Inc.
Copyright (c) 2009-2011 Advanced Micro Devices, Inc.
Copyright (c) 2009 The University of Edinburgh
Copyright (c) 2007-2008 The Florida State University
Copyright (c) 2010 Massachusetts Institute of Technology
Copyright (c) 1990-1993 The Regents of the University of California
Copyright (c) 2006-2009 Nathan Binkert
Copyright (c) 2001 The NetBSD Foundation, Inc.
Copyright (c) 2010-2011 Gabe Black
Copyright (c) 1994 Adam Glass
Copyright (c) 1990-1992 MIPS Computer Systems, Inc.
Copyright (c) 2004 Richard J. Wagner
Copyright (c) 2000 Computer Engineering and Communication Networks Lab
Copyright (c) 2001 Eric Jackson
Copyright (c) 1990 Hewlett-Packard Development Company
Copyright (c) 1994-1996 Carnegie-Mellon University.
Copyright (c) 1993-1994 Christopher G. Demetriou
Copyright (c) 1997-2002 Makoto Matsumoto and Takuji Nishimura
Copyright (c) 1998,2001 Manuel Bouyer.
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