Running a Debug build of objdump -objc-meta-data with a large Mach-O file is
currently unnecessarily slow.
With some local test input, this change reduces the run time from 75-85s down
to 15-20s.
The two changes are:
Assert on pointer equality not array equality
Replace vector<pair<address, symbol>> with DenseMap<address, symbol>
Additionally, use a std::unique_ptr rather than handling the memory manually.
Patch by Dave Lee!
llvm-svn: 291398