#6084: Add stg_ap_pnnv and related call patterns ---------------------------------+------------------------------------------ Reporter: SimonMeier | Owner: simonmar Type: feature request | Status: new Priority: normal | Milestone: 7.8.1 Component: Runtime System | Version: 7.4.1 Keywords: | Os: Unknown/Multiple Architecture: Unknown/Multiple | Failure: None/Unknown Difficulty: Unknown | Testcase: Blockedby: | Blocking: Related: | ---------------------------------+------------------------------------------ Comment(by simonmar): A better fix for this just occurred to me. If we're making a tail-call to an unknown function that would require multiple stack frames, we could attempt to shortcut it like this (pseudo code): {{{ if (GET_TAG(fun) != 0 && fun->header.info.f.arity == 5) { // make a fast call with args in regs } else { // make the slow call as before } }}} This is more code of course, but the advantage is that it doesn't require us to guess which call patterns we need. It could be enabled with -O2 only, and only if we're making a call that would need, say, 3 or more frames. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/6084#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler