* Fix an unsigned integer overflow in the logic that computes the
number of uncovered lines in a function.
* When aggregating region and line coverage summaries, take into account
that different instantiations may have a different number of regions.
The new test case provides test coverage for both bugs. I also verified
this change by preparing a coverage report for a stage2 build of llc --
the new assertions should detect any outstanding over-counting bugs.
Fixes PR34613.
llvm-svn: 313417
Vedant Kumar