Merges multiple cachegrind output files into one
cg_merge [options] [cachegrind-out-files...]
cg_merge sums together the outputs of multiple Cachegrind runs into a single output file.
-o outfile
Write the profile data to outfile rather than to standard output.
cg_annotate(1), valgrind(1), $INSTALL/share/doc/valgrind/html/index.html or http://www.valgrind.org/docs/manual/index.html.
Nicholas Nethercote.