@verbatim
Gimple Represented as Polyhedra. Copyright (C) 2006-2013 Free Software Foundation, Inc. Contributed by Sebastian Pop sebas.nosp@m.tian.nosp@m..pop@.nosp@m.inri.nosp@m.a.fr.
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with GCC; see the file COPYING3. If not see http://www.gnu.org/licenses/.
This pass converts GIMPLE to GRAPHITE, performs some loop
transformations and then converts the resulting representation back
to GIMPLE.
An early description of this pass can be found in the GCC Summit'06
paper "GRAPHITE: Polyhedral Analyses and Optimizations for GCC".
The wiki page http://gcc.gnu.org/wiki/Graphite contains pointers to
the related work.
One important document to read is CLooG's internal manual:
http://repo.or.cz/w/cloog-ppl.git?a=blob_plain;f=doc/cloog.texi;hb=HEAD
that describes the data structure of loops used in this file, and
the functions that are used for transforming the code.