#14068: Loopification using join points -------------------------------------+------------------------------------- Reporter: nomeata | Owner: nomeata Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: JoinPoints Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #13966 #14067 | Differential Rev(s): Phab:D3811 #14827 | Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj):
Because if drop itself is in an inner loop, something like map (\n -> drop n xs) [0..1000], then we have to allocate a box for the the I# to wrap the argument.
Ah, well that would ''also'' be true of any non-recursive function that was called in this way. I think you are claiming that all the extra allocation is due to boxing the arguments to a non-recursive function that is called repeatedly. That seems surprising, but perhaps it is true. If so, then I suppose a possible fix is to specialise non-recursive functions too. Maybe that would be good in general; I'm not sure. Might be worth trying... -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14068#comment:37 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler