#14683: Slow compile times for Happy-generated source -------------------------------------+------------------------------------- Reporter: harpocrates | Owner: (none) Type: bug | Status: new Priority: high | Milestone: 8.4.1 Component: Compiler | Version: 8.2.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by tdammers): Further profiling result: {{{ COST CENTRE MODULE SRC %time %alloc coercionKind Coercion compiler/types/Coercion.hs:1707:3-7 87.5 88.7 CoreTidy HscMain compiler/main/HscMain.hs:1253:27-67 3.1 3.3 simplCast-addCoerce Simplify compiler/simplCore/Simplify.hs:1225:53-71 2.8 2.8 simplCast Simplify compiler/simplCore/Simplify.hs:871:62-87 2.1 1.5 Stg2Stg HscMain compiler/main/HscMain.hs:1489:12-44 1.6 1.9 }}} In other words, we're spending close to 90% time and alloc on the `coercionKind` function. alexbiehl mentioned that #11735 might be related, in the sense that possible optimizations mentioned there could solve this performance problem here. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14683#comment:15 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler