And I'd suggest NOT doing loopification with every occurrence analysis;
#14152: Float exit paths out of recursive functions -------------------------------------+------------------------------------- Reporter: nomeata | Owner: (none) Type: task | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.1 Resolution: | Keywords: JoinPoints Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #14137 #10918 | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by nomeata): that feels far too often to me. The check of whether loopification can be done is pretty cheap, and falls out of Occurence Analysis anyways: I just check whether the occurrence info indicates that this is a recursive function that admits loopification: {{{ RecursiveTailCalled join_arity <- tailCallInfo occ }}} So don’t see a reason to check this every time. Once a binding is loopified, it is a recursive join point, and loopification does not look at it any more. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14152#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler