On 6/17/10, Roman Beslik
Hi. The following code compiles "A.hs" with GHC API: {{{ import GHC import Outputable import DynFlags ( defaultDynFlags ) libdir = "/usr/lib/ghc-6.12.1" targetFile = "A.hs" main = defaultErrorHandler defaultDynFlags $ do runGhc (Just libdir) $ do dflags <- fmap (\dflags -> dflags {optLevel = 2}) getSessionDynFlags
Hi, Roman -- The problem you're seeing, where insufficient optimization occurs, is in the above line. If I replace it with: dflags <- fmap (updOptLevel 2) getSessionDynFlags then I get a result where "maybe" has been inlined away. The reason is that the optimization sequence is controlled by several different fields within DynFlags, and just changing the optLevel field doesn't update the other fields. The updOptLevel function (defined in DynFlags, so you'll have to import that module explicitly) does. Also, I don't know what you're trying to do, but I recommend looking at GHC's External Core feature: http://www.haskell.org/ghc/docs/6.12.2/html/users_guide/ext-core.html and at the extcore and linkcore libraries: http://hackage.haskell.org/package/extcore http://hackage.haskell.org/package/linkcore IMO, it's easier than using the API to generate Core. If you find any problems with External Core or the packages above, let me know (I'm the maintainer). Cheers, Tim -- Tim Chevalier * http://cs.pdx.edu/~tjc * Often in error, never in doubt "I knew I'd hate Cobol the moment I saw they'd used 'perform' instead of 'do'." -- Larry Wall