Change CodeGen of global decls to key off of the name (instead of
  having multiple bindings from all the possible decls which
  conceptually map to the same global).

 - This eliminates CodeGen depending on the LLVM module for name
   lookup.

 - This also eliminates the need for ReplaceMapValuesWith (hurrah).

 - This handles lookups for FunctionDecls correctly in the presence of
   aliases, this was previously broken.

 - WIP: Can still clean up & unify variable and function emission.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@54382 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed