#9246: GHC generates poor code for repeated uses of min/max --------------------------------------------+------------------------------ Reporter: arotenberg | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 Resolution: | Keywords: Operating System: Windows | Architecture: x86_64 Type of failure: Runtime performance bug | (amd64) Test Case: | Difficulty: Unknown Blocking: | Blocked By: | Related Tickets: #6135 --------------------------------------------+------------------------------ Comment (by simonpj): Indeed! What Core would you ''like'' to see generates for examples like `UglyBranching`? The underlying difficulty is that the case-of-case transformation is utterly crucial for optimising Haskell programs, and it's hard to predict when it'll be unproductive, or even counter-productive. I'd welcome ideas. case-of-case is described in "A transformation based optimiser for Haskell", and (in passing) in many other papers. Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9246#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler