#4941: SpecConstr generates functions that do not use their arguments ---------------------------------+------------------------------------------ Reporter: simonpj | Owner: Type: task | Status: new Priority: normal | Milestone: _|_ Component: Compiler | Version: 7.0.1 Keywords: | Testcase: Blockedby: | Difficulty: Os: Unknown/Multiple | Blocking: Architecture: Unknown/Multiple | Failure: Runtime performance bug ---------------------------------+------------------------------------------
Comment(by rl): Why do you need SAT for stream fusion? The problem with pulling strictness analysis and w/w into the loop is that you basically need a SpecConstr/simplify loop with an unbounded number of iterations because strictness and w/w are only useful if you simplify afterwards. I implemented something like this (without strictness analysis) for the stream fusion paper - see the "Specialising on lambdas" bit in #855. It was awfully fragile. Perhaps it is possible to implement a combined shape/demand analysis which subsumes both the current strictness analysis and the analysis that is done by SpecConstr. Maybe SpecConstr could then subsume worker/wrapper as well. -- Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4941#comment:4> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler _______________________________________________ Glasgow-haskell-bugs mailing list Glasgow-haskell-bugs@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs