Support GHC 8.8.1 (fixes #19)

[maoe]

This PR adds support for GHC 8.8.1. The dependency on regex-tdfa-text has been superseded by the latest regex-tdfa.

[hvr]

@maoe can you try this PR with the branch tip of https://github.com/haskell-hvr/regex-tdfa/commits/master ?

[maoe]

@maoe can you try this PR with the branch tip of https://github.com/haskell-hvr/regex-tdfa/commits/master ?

Sure. I confirmed locally that --filter option worked fine. I just pushed 31c096c to make sure CI passes with all GHC versions.

[maoe]

CI was fine with the latest regex-tdfa. I've removed the source-repository-package change. Now this is ready for review.

[hvr]

@maoe Btw, what are regexes being used in ghc-dump for? Are they performance critical? I'm asking because I'm searching for real-world benchmarks to measure how much -O2 vs -O1 matters for regex-tdfa

[hvr]

@maoe fyi, http://hackage.haskell.org/package/regex-tdfa-1.3.1.0

[maoe]

@maoe Btw, what are regexes being used in ghc-dump for? Are they performance critical? I'm asking because I'm searching for real-world benchmarks to measure how much -O2 vs -O1 matters for regex-tdfa

ghc-dump-util uses regexes to filter output by a binding name. I'd say the performance is not critical unless the Core file is exceptionally big.

@maoe fyi, http://hackage.haskell.org/package/regex-tdfa-1.3.1.0

Thanks! I've confirmed this PR builds fine with the release version.