[X86][ISelDAG] Add missing fallback patterns for avx2 broadcast instructions.
Those patterns are used when the load cannot be folded into the related broadcast
during the select phase.
This happens when the load gets additional uses that were not anticipated during
the previous lowering phases (constant vector to constant load, then constant
load reused) or when selection DAG is not able to prove that folding the load
will not create a cycle in the DAG.

<rdar://problem/16074331>


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204631 91177308-0d34-0410-b5e6-96231b3b80d8
[PowerPC] Generate little-endian object files

As a first step towards real little-endian code generation, this patch
changes the PowerPC MC layer to actually generate little-endian object
files.  This involves passing the little-endian flag through the various
layers, including down to createELFObjectWriter so we actually get basic
little-endian ELF objects, emitting instructions in little-endian order,
and handling fixups and relocations as appropriate for little-endian.

The bulk of the patch is to update most test cases in test/MC/PowerPC
to verify both big- and little-endian encodings.  (The only test cases
*not* updated are those that create actual big-endian ABI code, like
the TLS tests.)

Note that while the object files are now little-endian, the generated
code itself is not yet updated, in particular, it still does not adhere
to the ELFv2 ABI.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204634 91177308-0d34-0410-b5e6-96231b3b80d8
Adding some very nascent information about the clang tablegen backends, with a promise to add more information later.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204635 91177308-0d34-0410-b5e6-96231b3b80d8
R600/SI: Move splitting 64-bit immediates to separate function.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204651 91177308-0d34-0410-b5e6-96231b3b80d8