the bytecode file for 176.gcc by about 200K (10%), and 254.gap by about 167K,
a 25% reduction. There is still a lot of room for improvement in the encoding
of the compaction table.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10913 91177308-0d34-0410-b5e6-96231b3b80d8