Power7 changes, introduction

[Michael Meissner <meissner at linux dot vnet dot ibm dot com>]

I think I'm at a reasonable stopping point on the power7 development, that it
is time to check the patches into the tree.  It would be real helpful if other
folk who use the powerpc could look at the changes to make sure we don't have
any bugs that would affect the powerpc port.  Except for some minor config
changes, all of the changes are in the rs6000 subdirectory.

The power7/VSX changes are based on the ISA 2.06 spec for the powerpc:
http://www.power.org/resources/downloads/PowerISA_V2.06_PUBLIC.pdf

Instead of dumping all of the patches into a giant megapatch, I am rewriting
the patch as a series of patches, that each add functionality.  Each patch will
build and run tests.  Hopefully each patch will be easier to remove.  Note,
there may be some initializations of variables, etc. that aren't used in the
current patch, but will be used in future patches.

In terms of testing, I am doing bootstrap builds and make check on a powerpc
64-bit linux system.  I am also building cross compilers for the E500 and
paired floating point (750cl), and building a vectorization test that I wrote
that writes every single simple operation in form that the compiler should
vectorize to see whether it vectorizes or not, and then comparing the assembly
language produced.

Note, at present, I have started with mainline subversion id #148616.  I have
made a branch with the changes, so if you want to just check out the branch and
try it out in your own environment, you can do so.  The branch is:
svn+ssh://@gcc.gnu.org/svn/gcc/branches/ibm/power7-tmp

-- 
Michael Meissner, IBM
4 Technology Place Drive, MS 2203A, Westford, MA, 01886, USA
meissner@linux.vnet.ibm.com