[weak vtables] Remove a bunch of weak vtables

This patch removes most of the trivial cases of weak vtables by pinning them to
a single object file.

Differential Revision: http://llvm-reviews.chandlerc.com/D2068

Reviewed by Andy

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194865 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAllocBase.h b/lib/CodeGen/RegAllocBase.h
index 9c00298..c17a8d9 100644
--- a/lib/CodeGen/RegAllocBase.h
+++ b/lib/CodeGen/RegAllocBase.h
@@ -57,6 +57,7 @@
 /// live range splitting. They must also override enqueue/dequeue to provide an
 /// assignment order.
 class RegAllocBase {
+  virtual void anchor();
 protected:
   const TargetRegisterInfo *TRI;
   MachineRegisterInfo *MRI;