llvm-cov show: -include-filename-regex counterpart for -ignore-filename-regex flag

[Viranchee]

Hi,
I am having a use case where I want to show code coverage for only a certain files of the program.
By far, my solution regex has been hacky:

To include only folders that start with SIL:

llvm-cov show ...
  -ignore-filename-regex [A-RT-Z].* # includes only files starting with S
  -ignore-filename-regex S[A-HJ-Z].* # includes files starting with SI
  -ignore-filename-regex SI[A-KM-Z].* # includes files starting with SIL

If there is a counterpart flag for this, it would be wonderful

llvm-cov show ...
  -include-filename-regex SIL.* # includes only files starting with SIL

I am willing to contribute to this as well.
This can be a good first issue. This is code for -ignore-filename-regex
CodeCoverage.cpp

[Viranchee]

#71716

I have added some code which allows for using argument: -ignore-filename-regex but haven't yet tested it.