Reorganize GlobalValueSummary with a "Flags" bitfield.

Right now it only contains the LinkageType, but will be extended
with "hasSection", "isOptSize", "hasInlineAssembly", etc.

Differential Revision: http://reviews.llvm.org/D19404

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@267319 91177308-0d34-0410-b5e6-96231b3b80d8
8 files changed