[C++11] Do not check __GXX_EXPERIMENTAL_CXX0X__.

Summary: Checking the experimental flag for C++0x is no longer needed.

Differential Revision: http://llvm-reviews.chandlerc.com/D3206

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204964 91177308-0d34-0410-b5e6-96231b3b80d8
[PowerPC] Fix v2f64 vector extract and related patterns

First, v2f64 vector extract had not been declared legal (and so the existing
patterns were not being used). Second, the patterns for that, and for
scalar_to_vector, should really be a regclass copy, not a subregister
operation, because the VSX registers directly hold both the vector and scalar data.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204971 91177308-0d34-0410-b5e6-96231b3b80d8
[X86][Vector Cost Model] Add a comment to explain the workaround
in my previous commit (r204884).

<rdar://problem/16381225>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204972 91177308-0d34-0410-b5e6-96231b3b80d8
Revert "[C++11] Do not check __GXX_EXPERIMENTAL_CXX0X__."

This reverts commit r204964 because it disabled "= delete", "constexpr"
and "explicit" on GCC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204973 91177308-0d34-0410-b5e6-96231b3b80d8
Temporarily remove assert while I dig in to issues that it's causing for LLDB.

<rdar://problem/16349536>



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204975 91177308-0d34-0410-b5e6-96231b3b80d8
[PowerPC] Don't remove self VSX copies in PPCInstrInfo::copyPhysReg

Because of how the allocation of VSX registers interacts with the call-lowering
code, we sometimes end up generating self VSX copies. Specifically, things like
this:
  %VSL2<def> = COPY %F2, %VSL2<imp-use,kill>
(where %F2 is really a sub-register of %VSL2, and so this copy is a nop)

The problem is that ExpandPostRAPseudos always assumes that *some* instruction
has been inserted, and adds implicit defs to it. This is a problem if no copy
was inserted because it can cause subtle problems during post-RA scheduling.
These self copies will have to be removed some other way.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204976 91177308-0d34-0410-b5e6-96231b3b80d8
Canonicalise Windows target triple spellings

Construct a uniform Windows target triple nomenclature which is congruent to the
Linux counterpart.  The old triples are normalised to the new canonical form.
This cleans up the long-standing issue of odd naming for various Windows
environments.

There are four different environments on Windows:

MSVC: The MS ABI, MSVCRT environment as defined by Microsoft
GNU: The MinGW32/MinGW32-W64 environment which uses MSVCRT and auxiliary libraries
Itanium: The MSVCRT environment + libc++ built with Itanium ABI
Cygnus: The Cygwin environment which uses custom libraries for everything

The following spellings are now written as:

i686-pc-win32 => i686-pc-windows-msvc
i686-pc-mingw32 => i686-pc-windows-gnu
i686-pc-cygwin => i686-pc-windows-cygnus

This should be sufficiently flexible to allow us to target other windows
environments in the future as necessary.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204977 91177308-0d34-0410-b5e6-96231b3b80d8