#9927: Should simplifier try more iterations? -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.11 Keywords: | Operating System: Architecture: Unknown/Multiple | Unknown/Multiple Difficulty: Unknown | Type of failure: Blocked By: | None/Unknown Related Tickets: | Test Case: | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- When compiling with the `devel1` build, we get debugging output while building libraries. I see a lot of warnings like this: {{{ WARNING: file compiler/simplCore/SimplCore.hs, line 592 Simplifier bailing out after 4 iterations [5024, 247, 22, 1] Size = {terms: 3,735, types: 3,028, coercions: 216} }}} It looks to me like the simplifier is doing quite a nice job and shouldn't give up so soon. Concretely, I propose: increase the cutoff and see what the effect is on timing of running the entire GHC build, at whatever settings a performance guru thinks appropriate (almost certainly ''not'' `devel1`!). Ideally, the testing would take place on ghcspeed, so that it's a controlled environment and can be compared nicely with historical performance. I have not carried out this proposal myself because I'm not sure if there are other issues at work here (I don't know the simplifier much at all), and I don't know if there is even a way to get ghcspeed to do this for us. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9927 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler