#9291: Don't reconstruct sum types if the type subtly changes -------------------------------------+------------------------------------- Reporter: schyler | Owner: nomeata Type: feature request | Status: closed Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2871 Wiki Page: | -------------------------------------+------------------------------------- Comment (by heisenbug): Replying to [comment:42 Joachim Breitner <mail@…>]:
In [changeset:"19d5c7312bf0ad9ae764168132aecf3696d5410b/ghc" 19d5c73/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="19d5c7312bf0ad9ae764168132aecf3696d5410b" Add a CSE pass to Stg (#9291)
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Introduces the flag -fstg-cse, enabled by default with -O for now. It might also be a good candidate for -O2.
Will you revisit the `-O2` inclusion sometime later? /me was always under the impression that all performance-increasing optimisations from `-O` would be included in `-O2`.
Differential Revision: https://phabricator.haskell.org/D2871 }}}
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