MC: Add support for .cfi_startproc simple

This commit allows LLVM MC to process .cfi_startproc directives when
they are followed by an additional `simple' identifier. This signals to
elide the emission of target specific CFI instructions that would
normally occur initially.

This fixes PR16587.

Differential Revision: http://llvm-reviews.chandlerc.com/D2624


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200227 91177308-0d34-0410-b5e6-96231b3b80d8
[CMake] Put *_exports into "Misc" folder.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200228 91177308-0d34-0410-b5e6-96231b3b80d8
Silence MSVC warning on 'uint16_t |= bool' with a cast

This isn't C4800, it's C4805.  MSVC says this is unsafe, but it
generates correct code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200229 91177308-0d34-0410-b5e6-96231b3b80d8
[DAGCombiner] Teach how to fold sext/aext/zext of constant build vectors.

This patch teaches the DAGCombiner how to fold a sext/aext/zext dag node when
the operand in input is a build vector of constants (or UNDEFs).

The inability to fold a sext/zext of a constant build_vector was the root
cause of some pcg bugs affecting vselect expansion on x86-64 with AVX support.

Before this change, the DAGCombiner only knew how to fold a sext/zext/aext of a
ConstantSDNode.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200234 91177308-0d34-0410-b5e6-96231b3b80d8