#15445: SPECIALIZE one of two identical functions does not fire well -------------------------------------+------------------------------------- Reporter: nobrakal | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.4.3 Resolution: | Keywords: Operating System: Linux | Architecture: x86_64 | (amd64) Type of failure: None/Unknown | Test Case: | simplCore/should_compile/T15445 Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): Ben had to revert this patch {{{ Revert "Don't inline functions with RULES too early" author Ben Gamari <ben@smart-cactus.org> Wed, 1 Aug 2018 11:42:19 +0100 (06:42 -0400) committer Ben Gamari <ben@smart-cactus.org> Wed, 1 Aug 2018 11:54:23 +0100 (06:54 -0400) This commit causes significant performance regressions: ``` bytes allocated value is too high: Expected T9872d(normal) bytes allocated: 578498120 +/-5% Lower bound T9872d(normal) bytes allocated: 549573214 Upper bound T9872d(normal) bytes allocated: 607423026 Actual T9872d(normal) bytes allocated: 677179968 Deviation T9872d(normal) bytes allocated: 17.1 % bytes allocated value is too high: Expected T9872c(normal) bytes allocated: 3096670112 +/-5% Lower bound T9872c(normal) bytes allocated: 2941836606 Upper bound T9872c(normal) bytes allocated: 3251503618 Actual T9872c(normal) bytes allocated: 3601872536 Deviation T9872c(normal) bytes allocated: 16.3 % bytes allocated value is too high: Expected T9872b(normal) bytes allocated: 3730686224 +/-5% Lower bound T9872b(normal) bytes allocated: 3544151912 Upper bound T9872b(normal) bytes allocated: 3917220536 Actual T9872b(normal) bytes allocated: 4374298272 Deviation T9872b(normal) bytes allocated: 17.3 % bytes allocated value is too high: Expected T9872a(normal) bytes allocated: 2729927408 +/-5% Lower bound T9872a(normal) bytes allocated: 2593431037 Upper bound T9872a(normal) bytes allocated: 2866423779 Actual T9872a(normal) bytes allocated: 3225788896 Deviation T9872a(normal) bytes allocated: 18.2 % ``` It's not clear that this was intentional so I'm going to revert for now. This reverts commit 2110738b280543698407924a16ac92b6d804dc36. }}} -- Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15445#comment:6> GHC <http://www.haskell.org/ghc/> The Glasgow Haskell Compiler