[GHC] #12367: Commit adding instances to GHC.Generics regression compiler performance
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 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: -------------------------------------+------------------------------------- Recently 673efccb3b348e9daf23d9e65460691bbea8586e added a number of new instances for types defined in `GHC.Generics`. Unfortunately, it seems that this has regressed nofib compilation allocations (and also, it seems, compile time) by about 10%. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 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: | -------------------------------------+------------------------------------- @@ -4,1 +4,1 @@ - compile time) by about 10%. + compile time) by between 0 and 20% (on average about 5%). New description: Recently 673efccb3b348e9daf23d9e65460691bbea8586e added a number of new instances for types defined in `GHC.Generics`. Unfortunately, it seems that this has regressed nofib compilation allocations (and also, it seems, compile time) by between 0 and 20% (on average about 5%). -- Comment (by bgamari): ||= Test name =||= Absolute change =||= relative change =|| || compile-allocs/MyList || 20238384 || 0.208624775040415 || || compile-allocs/MyList || 20281496 || 0.206217801180845 || || compile-allocs/Prog || 20334192 || 0.202959317331712 || || compile-allocs/Prog || 20344656 || 0.20053198007393 || || compile-allocs/Basics || 22115840 || 0.185615422473695 || || compile-allocs/Basics || 22149816 || 0.183089910175923 || || compile-allocs/Assemble_loadvec || 20347184 || 0.166966893079396 || || compile-allocs/Digraph || 21606168 || 0.166243308385695 || || compile-allocs/Assemble_loadvec || 20357600 || 0.165346296105217 || || compile-allocs/Shows || 20296024 || 0.165204453781781 || || compile-allocs/Digraph || 21659944 || 0.165084805640568 || || compile-allocs/Shows || 20338616 || 0.163719820616552 || || compile-allocs/Tol_cal || 20737568 || 0.161829271665394 || || compile-allocs/Queue || 20579112 || 0.161181557853612 || || compile-allocs/Tol_cal || 20731568 || 0.160175008827888 || || compile-allocs/Queue || 20600368 || 0.159599282181737 || || compile-allocs/Vtslib || 20374904 || 0.155144898631996 || || compile-allocs/Match || 20975896 || 0.154183839207216 || || compile-allocs/Vtslib || 20368168 || 0.153618623974637 || || compile-allocs/Match || 21000088 || 0.152948131340001 || || compile-allocs/Preds || 20369168 || 0.150245373920468 || || compile-allocs/Preds || 20382840 || 0.14899133906394 || || compile-allocs/BinConv || 21814376 || 0.147565217236013 || || compile-allocs/BinConv || 21843560 || 0.146507544982022 || || compile-allocs/Shapes || 20121512 || 0.144706659929922 || -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 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 bgamari): To characterize this further I chose a representative module from nofib (the `Psfuns` module of the `reptile` test) and compiled it with 6319a8cf79cc1f1e25220113149ab48e5083321b (the parent of the change) and 673efccb3b348e9daf23d9e65460691bbea8586e built with ticky enabled. The largest changes are summarized below. ||= Change =||= alloc A =||= alloc B =||= name =|| || +2898040.0 || 13460520 || 16358560 || `$wa5 (ghc-8.1:Encoding)` || || +2247360.0 || 6593640 || 8841000 || ` (ghc-8.1:Unique.mkUnique)` || || +1976688.0 || 8486408 || 10463096 || `a4 (ghc-8.1:IOEnv)` || || +1734288.0 || 5736672 || 7470960 || ` (ghc-8.1:FastString.uniq)` || || +1632784.0 || 5415504 || 7048288 || `$cgetUnique2 (ghc-8.1:Unique)` || || +1258016.0 || 3014864 || 4272880 || ` (ghc-8.1:Binary.getByte1)` || || +1229472.0 || 4354032 || 5583504 || `$ccompare1 (ghc-8.1:Module)` || || +1210656.0 || 3661152 || 4871808 || `$ccompare (ghc-8.1:Module)` || || +1083360.0 || 2529840 || 3613200 || `$cget6 (ghc-8.1:IfaceType)` || || +994560.0 || 2327440 || 3322000 || `$wa1 (ghc-8.1:BinIface.)` || || +960600.0 || 2005200 || 2965800 || `$cget5 (ghc-8.1:IfaceType)` || || +946824.0 || 2020656 || 2967480 || `$wa3 (ghc-8.1:BinIface)` || || +558992.0 || 1389872 || 1948864 || `$wa8 (ghc-8.1:Binary.)` || || +558200.0 || 1193720 || 1751920 || `$cget1 (ghc-8.1:IfaceType)` || || +551320.0 || 1149720 || 1701040 || `$cget2 (ghc-8.1:IfaceType)` || || +473088.0 || 1268960 || 1742048 || ` (ghc-8.1:TysWiredIn.isBuiltInOcc_maybe)` || || +318136.0 || 1234352 || 1552488 || `a5 (ghc-8.1:IOEnv)` || || +305280.0 || 4939520 || 5244800 || ` (ghc-8.1:UniqFM.lookupUFM)` || || +297216.0 || 691920 || 989136 || ` (ghc-8.1:UniqFM.lookupUFM_Directly)` || || +286200.0 || 889680 || 1175880 || `$wa17 (ghc-8.1:Binary.)` || || +253952.0 || 560000 || 813952 || `a18 (ghc-8.1:BinIface)` || || +217992.0 || 1167832 || 1385824 || `$wa (ghc-8.1:FastString.)` || || +187792.0 || 595672 || 783464 || ` (ghc-8.1:IfaceEnv.lookupOrig)` || || +173720.0 || 566160 || 739880 || ` (ghc-8.1:FastString.unpackFS)` || || +173504.0 || 397760 || 571264 || `$wa11 (ghc-8.1:Binary.)` || || +170560.0 || 694272 || 864832 || `a (ghc-8.1:IOEnv)` || || +148992.0 || 3369216 || 3518208 || `a23 (ghc-8.1:UniqFM)` || || +137376.0 || 456528 || 593904 || ` (ghc-8.1:Unique.mkVarOccUnique)` || || +134320.0 || 2260808 || 2395128 || ` (ghc-8.1:DynFlags.dopt)` || || +133448.0 || 413840 || 547288 || `$wxs (ghc-8.1:Binary)` || || +117936.0 || 363664 || 481600 || ` (ghc-8.1:IfaceEnv.extendNameCache)` || || +117544.0 || 401520 || 519064 || ` (ghc-8.1:Name.mkExternalName)` || || +114240.0 || 265632 || 379872 || `$fBinary(,)`1 (ghc-8.1:Binary.) || || +110992.0 || 243824 || 354816 || `$wxs (ghc-8.1:BinIface)` || || +108480.0 || 222640 || 331120 || `$cget (ghc-8.1:TyCoRep)` || || +108480.0 || 222640 || 331120 || `$cget4 (ghc-8.1:IfaceType)` || || +106920.0 || 473448 || 580368 || `$wa83 (ghc-8.1:Binary)` || || +105888.0 || 229248 || 335136 || ` (ghc-8.1:TcRnMonad.forkM)` || || +104232.0 || 340752 || 444984 || `$wa2 (ghc-8.1:Encoding.)` || || +103200.0 || 385296 || 488496 || ` (ghc-8.1:UniqSupply.takeUniqFromSupply)` || || +98576.0 || 263312 || 361888 || `$wa6 (ghc-8.1:Binary.)` || || +93600.0 || 197040 || 290640 || `$cget1 (ghc-8.1:OccName)` || -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 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 bgamari): It turns out that the problem is actually a fair bit worse than described above. While `Foldable` imports `GHC.Generics` in order to provide instances for types in the latter (which should be fairly easy to fix with some reorganization), the other modules import `GHC.Generics merely to derive `Generic` instances for types they themselves define. One example of this is `Data.Monoid`, which defines a number of `newtype`s resembling, {{{#!hs newtype All = All { getAll :: Bool } deriving (Eq, Ord, Read, Show, Bounded, Generic) }}} It seems to me like we may want to consider moving the data types defined in `GHC.Generics` to a new `GHC.Generic.Internal` module. They could then be re-exported in `GHC.Generics`, which could also derive instances for these types. This would also allow us to move the `Foldable` instances for the generics types to `GHC.Generics`, since the latter could likely import `Data.Foldable` without fear of cycles. Really, though, this arguably leaves a large portion of the problem unsolved: users who use `GHC.Generics` (which is increasingly popular) still need to pay the full cost of importing it. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 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: | -------------------------------------+------------------------------------- Changes (by bgamari): * cc: RyanGlScott (added) Comment: Ccing RyanGlScott, who authored 673efccb3b348e9daf23d9e65460691bbea8586e. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 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 bgamari): I should note that the problem of adding instances to core libraries degrading compiler performance is a rather general theme. It can also be found in 4e6bcc2c8134f9c1ba7d715b3206130f23c529fb, which adds a number of instances to `Data.Monoid` and regresses compiler allocations by 5 to 10%. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics 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: | -------------------------------------+------------------------------------- Changes (by RyanGlScott): * keywords: => Generics -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics 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 bgamari): In our call yesterday Simon expressed skepticism that the performance regression is entirely due to a larger interface file. More like, he said, is that an interface is now being loaded which wasn't previously necessary. Indeed this is the case: interface files for both `GHC.Generics` and `GHC.Ptr` are now loaded while compiling `Data.Foldable` but were not previously, {{{ $ grep 'Reading interface' dump-if.log Reading interface for Prelude; reason: Prelude is directly imported Reading interface for Geomfuns; Reading interface for Auxprogfuns; Reading interface for GHC.Base; Reading interface for GHC.Float; Reading interface for GHC.Types; Reading interface for Data.Foldable; Reading interface for GHC.List; Reading interface for GHC.Show; Reading interface for GHC.Prim; Reading interface for GHC.Classes; reason: Need decl for Eq Reading interface for GHC.Num; reason: Need decl for Num Reading interface for GHC.Stack.Types; reason: Need decl for SrcLoc Reading interface for GHC.Integer.Type; Reading interface for GHC.Generics; reason: Need decl for V1 Reading interface for GHC.Ptr; reason: Need decl for Ptr Reading interface for Data.Monoid; reason: Need decl for Sum Reading interface for Data.Proxy; reason: Need decl for Proxy Reading interface for Data.Either; reason: Need decl for Either Reading interface for GHC.Arr; reason: Need decl for Array Reading interface for GHC.Tuple; Reading interface for GHC.Enum; reason: Need decl for enumFromTo Reading interface for GHC.CString; }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics 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 bgamari): It's not entirely clear how to proceed from here. The problem here is that we want to provide `Generic` instances for many types in `base`, while at the same time providing, e.g., `Foldable` and `Monoid` instances for the generic representation types. As far as I can tell we have a few options, 1. Keep the status quo and accept the fact that much of `base` pulls is `GHC.Generics` 2. Move the data types in `GHC.Generics` to a new `GHC.Generics.Internal` module, placing the the instances in `GHC.Generics`. This would mean that `GHC.Generics` would be full of orphans but that fewer modules within `base` would need to import the full bulk of the instances. That being said, this does nothing to help users who use `GHC.Generics` but none of the instances. 3. Wire-in the generics representation types to hopefully avoid the need to pull in the interface file at all when deriving `Generic` (assuming that GHC in fact is capable to avoid pulling in interface files when loading only wired-in declarations). 4. Add `hs-boot` files for `Foldable`, `Traversable`, et al., allowing us to move the instances for the `GHC.Generics` types to `GHC.Generics` 5. Something else? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics 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 simonpj): We can't move to a solution until we know WHY `GHC.Ptr` and `GHC.Generics` are being read. Why do we need `V1` and `Ptr` when we didn't before. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:9 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics 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 bgamari): Simonpj, `GHC.Generics` is read because `Data.Foldable` provides a `Foldable` instance for `GHC.Generics.V1`. `GHC.Ptr` is read because `GHC.Generics` needs `GHC.Ptr.Ptr` to define instances for representing `Addr#` fields. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:10 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics 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: | -------------------------------------+------------------------------------- Changes (by bgamari): * cc: bgamari (added) -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:11 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics 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 bgamari): So it appears that something is indeed calling for the `V1` dictionary and is therefore forcing the load of the `GHC.Generics` interface file, {{{ ... end stage interact with inerts } runStage top-level reactions { workitem = [W] $dFoldable_a2pp :: Foldable [] (CDictCan) doTopReact [W] $dFoldable_a2pp :: Foldable [] (CDictCan) matchClassInst pred = Foldable [] Starting fork { Dict fun $fFoldable[] ... } ending fork Dict fun $fFoldable[] Starting fork { Dict fun $fFoldableV1 Starting fork { Declaration for $fFoldableV1 Loading decl for $fFoldableV1 updating EPS_ Need decl for V1 Considering whether to load GHC.Generics {- SYSTEM -} Reading interface for GHC.Generics; reason: Need decl for V1 ... }}} Now to work out what. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:12 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics 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 bgamari): This minimal program is enough to trigger `GHC.Generics` to be loaded with 673efccb3b348e9daf23d9e65460691bbea8586e yet not without, {{{#!hs module OhNoTooManyInterfaces where concrep :: Int -> [a] -> [a] concrep x y = concat (take x (repeat y)) }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:13 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: new Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics 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 bgamari): I've made a bit of progress tracking down the cause of GHC.Generics being loaded when looking for a `Foldable []` instance. It looks like the cause is the evaluation of the `mod` binding in IfaceEnv.instIsVisible. The RHS of this binding pulls on is_dfun to get its `idName` (which it only need the Module from). -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:14 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance
-------------------------------------+-------------------------------------
Reporter: bgamari | Owner: bgamari
Type: bug | Status: new
Priority: normal | Milestone: 8.0.2
Component: Compiler | Version: 8.0.1
Resolution: | Keywords: Generics
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: |
-------------------------------------+-------------------------------------
Changes (by simonpj):
* cc: ezyang (added)
Comment:
Great catch! This is all Edward's fault :-).
{{{
commit 4c834fdddf4d44d12039da4d6a2c63a660975b95
Author: Edward Z. Yang
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: patch Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2411 Wiki Page: | -------------------------------------+------------------------------------- Changes (by bgamari): * status: new => patch * differential: => Phab:D2411 Comment: Here's a quick attempt at fixing this. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:16 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: patch Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2411 Wiki Page: | -------------------------------------+------------------------------------- Comment (by bgamari): One thing I also noticed while debugging this is that the `relevantBindings` logic in `TcErrors` appears to pull in `GHC.Generics` when generating an error, even when no relevant bindings are shown in the resulting message (and even with `-fmax-relevant-binds=0`). Judging from the comments surrounding `relevantBindings`, it sounds like this is expected behavior but I thought I'd mention it anyways. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:17 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: patch Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2411 Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj): Patch looks good. I have commented it. I don't understand why `relevantBindings` would pull in anything. What "surrounding comments"? Do you know why it pulls `GHC.Generics` in? Worth understanding... -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:18 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: patch Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2411 Wiki Page: | -------------------------------------+------------------------------------- Changes (by simonmar): * cc: simonmar (added) -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:19 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance
-------------------------------------+-------------------------------------
Reporter: bgamari | Owner: bgamari
Type: bug | Status: patch
Priority: normal | Milestone: 8.0.2
Component: Compiler | Version: 8.0.1
Resolution: | Keywords: Generics
Operating System: Unknown/Multiple | Architecture:
Type of failure: Compile-time | Unknown/Multiple
performance bug | Test Case:
Blocked By: | Blocking:
Related Tickets: | Differential Rev(s): Phab:D2411
Wiki Page: |
-------------------------------------+-------------------------------------
Comment (by Ben Gamari
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: patch Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2411 Wiki Page: | -------------------------------------+------------------------------------- Comment (by bgamari): The commit in comment:20 should hopefully make a significant dent in allocations. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:21 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: patch Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Generics Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2411 Wiki Page: | -------------------------------------+------------------------------------- Comment (by bgamari): comment:20 merged to `ghc-8.0` with 291b439fb1da7af4401477c92ba24c7b4b498df8. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:22 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
#12367: Commit adding instances to GHC.Generics regression compiler performance -------------------------------------+------------------------------------- Reporter: bgamari | Owner: bgamari Type: bug | Status: closed Priority: normal | Milestone: 8.0.2 Component: Compiler | Version: 8.0.1 Resolution: fixed | Keywords: Generics Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2411 Wiki Page: | -------------------------------------+------------------------------------- Changes (by bgamari): * status: patch => closed * resolution: => fixed Comment: It seems that the underlying issue here (the lack of laziness in the instance visibility check resulting in unnecessary typechecking) has been solved. Closing. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12367#comment:23 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler
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