PATCH: Add SSE4.1 support

[Uros Bizjak]

Hello!

> This update adds prefix_extra to SSE4.1 instructions for longer
> opcodes. I also removed ix86_expand_sse4_unpack since a new approach
> is needed for the vectorizer to fully support SSE4.1.

> 2007-04-24  H.J. Lu  <hongjiu.lu@intel.com>
> 	    Richard Henderson  <rth@redhat.com>
...
>	* config/i386/smmintrin.h: New. The SSE4.1 intrinsic header
> 	file.

In order to test this header for compile-time failures, an inlined
versions for all #defined functions should be added (guarded with
#ifdef __OPTIMIZE__), as was recently changed in SVN mainline.

Following that change, please update following files in the testsuite:

gcc.target/i386/sse-12.c
gcc.target/i386/sse-13.c
gcc.target/i386/sse-14.c
g++.dg/other/i386-2.C

This will test your header as much as possible for optimized and
unoptimized builds.

Considering that this is mostly new functionality (already reviewed by
rth), that it will be thoroughly tested by provided tests [1] and that
no other i386 maintainer raised any issue with latest version of
patch, it is OK for mainline.

[1] http://gcc.gnu.org/ml/gcc-patches/2007-05/msg01361.html

Thanks,
Uros.