switch valuemap's from std::map to densemap.  This speeds up llvm-dis
on a stripped kc++ .bc file from 0.83 to 0.77s (8%)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54896 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed