gcc44, add graphite support

[bcbarnes@…]

GCC 4.4 adds support for advanced loop optimizations in the "graphite" branch of the compiler. These are not compiled by default, but could be extremely useful for people doing numerical/scientific work.

​http://gcc.gnu.org/gcc-4.4/changes.html instructions for building the graphite branch are here: ​http://gcc.gnu.org/wiki/Graphite_Build

Could we get a variant of the gcc44 port which supports graphite, or perhaps even enable it by default?

Thanks!

[ryandesign@…]

See also #26043.

[adfernandes@…]

Committed in r92829 (for gcc46 and gcc47; prior versions require cloog-ppl which is old and no longer supported).