It appears when testing LLVM 13 on Power, we run into failures with the libcxx/test/libcxx/gdb/gdb_pretty_printer_test.sh.cpp
test case optimizing values out.
Despite some the functions in the test already being marked with optnone, adding the MarkAsLive()
calls inside of the pretty printer comparison functions resolves the issues of the values being optimized out.
This patch aims to address https://bugs.llvm.org/show_bug.cgi?id=51675.