[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. The memory leaks in this version have been fixed. Thanks
Alexey for pointing them out.

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

Reviewed by Andy

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195064 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/RegAllocBase.cpp

@@ -50,6 +50,9 @@ bool RegAllocBase::VerifyEnabled = false;
 //                         RegAllocBase Implementation
 //===----------------------------------------------------------------------===//
 
+// Pin the vtable to this file.
+void RegAllocBase::anchor() {}
+
 void RegAllocBase::init(VirtRegMap &vrm,
                         LiveIntervals &lis,
                         LiveRegMatrix &mat) {