original commit msg:
MemoryBuiltins: add support to determine the size of strdup'ed non-constant strings
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160751 91177308-0d34-0410-b5e6-96231b3b80d8
Make sure we do not emit index computations with NSW flags so that we dont get an undef value if the GEP overflows
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160589 91177308-0d34-0410-b5e6-96231b3b80d8