change the concatenation avoidance algorithm to be partially table-driven
and avoid computing the spelling of tokens when not needed.  This speeds
up -E on 447.dealII by 2.2%


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@40421 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed