For PR1297:

For PR1297:
Intrinsic functions might need to be generated (if they are overloaded) so
returning a const char* is no longer possible. Change getOperationName to
return a std::string instead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35543 91177308-0d34-0410-b5e6-96231b3b80d8