#5615: ghc produces poor code for `div` with constant powers of 2. -------------------------------------+------------------------------------- Reporter: Lennart | Owner: akio Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.4.1-rc1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: x86 Type of failure: Runtime | Test Case: performance bug | Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2486 Wiki Page: | -------------------------------------+------------------------------------- Changes (by akio): * owner: daniel.is.fischer => akio * differential: => Phab:D2486 Comment: I implemented rules for `div` and `mod`. I decided not to do anything with Euclidean division because (1) the rules I added are valid for the current semantics (floor division) as well as for Euclidean division, and (2) I believe that changing the semantics of `div` and `mod` is a much bigger change and should be discussed separately. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/5615#comment:30 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler