Correctly update dom-tree after loop vectorizer.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221009 91177308-0d34-0410-b5e6-96231b3b80d8
Sink some of DwarfDebug::collectDeadVariables down into DwarfCompileUnit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221010 91177308-0d34-0410-b5e6-96231b3b80d8
Suppress MSVC's equivalent of -Wshadow warnings

IMO we need to clean up some of these, but the member variable one
(C4458) has false positives on static methods.  It is currently firing
on Twine, which has a static method like:
  struct Twine {
    uintptr_t LHS, RHS;
    static void staticMethod() {
      // warning C4458: declaration of 'LHS' hides class member
      uintptr_t LHS;
      ...
    }
  };

We should fix up clang's -Wshadow and clean it up, and then we can
re-enable some of these MSVC warnings.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221012 91177308-0d34-0410-b5e6-96231b3b80d8
Define LLVM_NOEXCEPT with MSVC 14 CTP 3 or newer

We have to use _MSC_FULL_VER here as CTP 2 and earlier didn't define
noexcept to my knowledge.

Fixes build error in lib/Support/Error.cpp when inheriting from
std::error_category, which has a noexcept virtual method.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221013 91177308-0d34-0410-b5e6-96231b3b80d8
Refactor duplicated code in liking GlobalValues.

There is quiet a bit of logic that is common to any GlobalValue but was
duplicated for Functions, GlobalVariables and GlobalAliases.

While at it, merge visibility even when comdats are used, fixing pr21415.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@221014 91177308-0d34-0410-b5e6-96231b3b80d8