#7116: Missing optimisation: strength reduction of floating-point multiplication --------------------------------------------+------------------------------ Reporter: simonmar | Owner: Type: bug | Status: patch Priority: normal | Milestone: 7.8.1 Component: Compiler | Version: 7.4.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Runtime performance bug | Unknown/Multiple Test Case: | Difficulty: Unknown Blocking: | Blocked By: | Related Tickets: --------------------------------------------+------------------------------ Comment (by simonmar): jstolarek: the ticket is about doing the optimisation for floating-point multiplication, not integer. We don't want to do it for integer operations, because it's better to do this in the code generator (the only reason for doing it in the simplifier would be to enable further simplifications, but that isn't the case here). Furthermore, we definitely want to optimise integer multiplication at the Cmm level, because the Stg->Cmm code generator and later stages may create opportunities for this optimisation. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/7116#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler