1. 01 Jul, 2016 1 commit
    • niteria's avatar
      Remove uniqSetToList · cbfeff4b
      niteria authored
      This documents nondeterminism in code generation and removes
      the nondeterministic ufmToList function. In the future someone
      will have to use nonDetEltsUFM (with proper explanation)
      or pprUFM.
      cbfeff4b
  2. 30 Jun, 2016 1 commit
    • niteria's avatar
      Remove ufmToList · 480e0661
      niteria authored
      This documents nondeterminism in code generation and removes
      the nondeterministic ufmToList function. In the future someone
      will have to use nonDetUFMToList (with proper explanation)
      or pprUFMWithKeys.
      480e0661
  3. 27 Jun, 2016 1 commit
    • Ömer Sinan Ağacan's avatar
      Remove some `undefined`s · 82282e8d
      Ömer Sinan Ağacan authored
      These get annoying when `undefined` is actually used as placeholder in WIP code.
      Some of these were also completely redundant (just call `deAnnotate'` instead of
      `deAnnotate` etc.).
      82282e8d
  4. 23 Jun, 2016 1 commit
    • niteria's avatar
      Provide Uniquable version of SCC · 35d1564c
      niteria authored
      We want to remove the `Ord Unique` instance because there's
      no way to implement it in deterministic way and it's too
      easy to use by accident.
      
      We sometimes compute SCC for datatypes whose Ord instance
      is implemented in terms of Unique. The Ord constraint on
      SCC is just an artifact of some internal data structures.
      We can have an alternative implementation with a data
      structure that uses Uniquable instead.
      
      This does exactly that and I'm pleased that I didn't have
      to introduce any duplication to do that.
      
      Test Plan:
      ./validate
      I looked at performance tests and it's a tiny bit better.
      
      Reviewers: bgamari, simonmar, ezyang, austin, goldfire
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2359
      
      GHC Trac Issues: #4012
      35d1564c
  5. 06 Jun, 2016 4 commits
    • niteria's avatar
      Make UnitIdMap a deterministic map · 1937ef1c
      niteria authored
      This impacts at least the order in which version macros are
      generated. It's pretty hard to track what kind of nondeterminism
      is benign and this should have no performance impact as the number
      of packages should be relatively small.
      
      Test Plan: ./validate
      
      Reviewers: simonmar, austin, bgamari, ezyang
      
      Reviewed By: ezyang
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2308
      
      GHC Trac Issues: #4012
      1937ef1c
    • niteria's avatar
      Kill foldUniqSet · 3e7a876a
      niteria authored
      I planned to just say that we don't care about this part.
      Turns out I was able to document away the uses in the codegenerator.
      
      Test Plan: ./validate
      
      Reviewers: simonmar, austin, bgamari
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2307
      
      GHC Trac Issues: #4012
      3e7a876a
    • niteria's avatar
      Document putDictionary determinism · 46d2da00
      niteria authored
      Summary: Like explained in the comment it's OK here.
      
      Test Plan: ./validate
      
      Reviewers: simonmar, austin, bgamari
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2306
      
      GHC Trac Issues: #4012
      46d2da00
    • niteria's avatar
      Use UniqDFM for HomePackageTable · 3042a9d8
      niteria authored
      This isn't strictly necessary for deterministic ABIs.
      The results of eltsHpt are consumed in two ways:
      1) they determine the order of linking
      2) if you track the data flow all the family instances get put in
         FamInstEnvs, so the nondeterministic order is forgotten.
      3) same for VectInfo stuff
      4) same for Annotations
      
      The problem is that I haven't found a nice way to do 2. in
      a local way and 1. is nice to have if we went for deterministic
      object files. Besides these maps are keyed on ModuleNames so they
      should be small relative to other things and the overhead should
      be negligible.
      
      As a bonus we also get more specific names.
      
      Test Plan: ./validate
      
      Reviewers: bgamari, austin, hvr, ezyang, simonmar
      
      Reviewed By: simonmar
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2300
      
      GHC Trac Issues: #4012
      3042a9d8
  6. 03 Jun, 2016 1 commit
    • niteria's avatar
      Make FieldLabelEnv a deterministic set · 9cc6fac5
      niteria authored
      This lets us kill fsEnvElts function which is nondeterministic.
      We also get better guarantees than just comments.
      We don't do lookups, but I believe a set is needed for deduplication.
      
      Test Plan: ./validate
      
      Reviewers: bgamari, mpickering, austin, simonmar
      
      Reviewed By: simonmar
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2297
      
      GHC Trac Issues: #4012
      9cc6fac5
  7. 24 May, 2016 3 commits
    • Ryan Scott's avatar
      Remove 'deriving Typeable' statements · 95dfdceb
      Ryan Scott authored
      Summary:
      Deriving `Typeable` has been a no-op since GHC 7.10, and now that we
      require 7.10+ to build GHC, we can remove all the redundant `deriving Typeable`
      statements in GHC.
      
      Test Plan: ./validate
      
      Reviewers: goldfire, austin, hvr, bgamari
      
      Reviewed By: austin, hvr, bgamari
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2260
      95dfdceb
    • niteria's avatar
      Make Arrow desugaring deterministic · 9d06ef1a
      niteria authored
      This kills two instances of varSetElems that turned out to be
      nondeterministic. I've tried to untangle this before, but it's
      a bit hard with the fixDs in the middle. Fortunately I now have
      a test case that proves that we need determinism here.
      
      Test Plan: ./validate, new testcase
      
      Reviewers: simonpj, simonmar, austin, bgamari
      
      Reviewed By: bgamari
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2258
      
      GHC Trac Issues: #4012
      9d06ef1a
    • niteria's avatar
      Document some benign nondeterminism · 4c6e69d5
      niteria authored
      I've changed the functions to their nonDet equivalents and explained
      why they're OK there. This allowed me to remove foldNameSet,
      foldVarEnv, foldVarEnv_Directly, foldVarSet and foldUFM_Directly.
      
      Test Plan: ./validate, there should be no change in behavior
      
      Reviewers: simonpj, simonmar, austin, goldfire, bgamari
      
      Reviewed By: bgamari
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2244
      
      GHC Trac Issues: #4012
      4c6e69d5
  8. 23 May, 2016 1 commit
    • Ben Gamari's avatar
      Revert "compiler/iface: compress .hi files" · 9bb27726
      Ben Gamari authored
      This appears to cause validation issues on,
      
          TEST="T11108 T9071 T11076 T7600 T7672 T8329 T10420 T10322 T8308 T4114a
          T4114c T10602 T10110 T9204 T2435 T9838 T4114d T10233 T8696 T1735 T5281
          T6056 T10134 T9580 T6018 T9762 T8103"
      
      With compiler panics of the form,
      
          Compile failed (status 256) errors were:
          ghc: panic! (the 'impossible' happened)
            (GHC version 8.1.20160523 for x86_64-unknown-linux):
                  Binary.readBinMem: decompression failed
          CallStack (from HasCallStack):
            error, called at compiler/utils/Binary.hs:192:16 in ghc:Binary
      
          Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
      
      This reverts commit d9cb7a8a.
      9bb27726
  9. 21 May, 2016 1 commit
    • Austin Seipp's avatar
      compiler/iface: compress .hi files · d9cb7a8a
      Austin Seipp authored
      Compress all interface files generated by the compiler with LZ4. While
      being only a tiny amount of code, LZ4 is both fast at compression and
      decompression, and has good compression ratios.
      
      Non-scientific size test: size of stage2 compiler .hi files:
      
      `find ./compiler/stage2 -type f -iname '*.hi' -exec du -ch {} + | grep total$`
      
      Without this patch: 22MB of .hi files for stage2.
      With this patch: 9.2MB of .hi files for stage2.
      Signed-off-by: default avatarAustin Seipp <austin@well-typed.com>
      
      Reviewed By: bgamari
      
      Differential Revision: https://phabricator.haskell.org/D1159
      d9cb7a8a
  10. 18 May, 2016 1 commit
    • niteria's avatar
      Make inert_model and inert_eqs deterministic sets · fffe3a25
      niteria authored
      The order inert_model and intert_eqs fold affects the order that the
      typechecker looks at things. I've been able to experimentally confirm
      that the order of equalities and the order of the model matter for
      determinism. This is just a straigthforward replacement of
      nondeterministic VarEnv for deterministic DVarEnv.
      
      Test Plan: ./validate
      
      Reviewers: simonpj, goldfire, austin, bgamari, simonmar
      
      Reviewed By: simonmar
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2232
      
      GHC Trac Issues: #4012
      fffe3a25
  11. 12 May, 2016 2 commits
  12. 11 May, 2016 1 commit
    • niteria's avatar
      Document SCC determinism · 3edbd091
      niteria authored
      I've documented the guarantees that stronglyConnCompFromEdgedVertices
      provides and commented on the call sites to explain why they are
      OK from determinism standpoint. I've changed the functions to
      nonDetUFM versions, so that it's explicit they could introduce
      nondeterminism.  I haven't defined container (VarSet, NameSet)
      specific versions, so that we have less functions to worry about.
      
      Test Plan: this is mostly just documentation,
      it should have no runtime effect
      
      Reviewers: bgamari, simonmar, austin, simonpj
      
      Reviewed By: simonpj
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2194
      
      GHC Trac Issues: #4012
      3edbd091
  13. 10 May, 2016 1 commit
    • niteria's avatar
      Get rid of Traversable UniqFM and Foldable UniqFM · 7e28e47c
      niteria authored
      Both Traversable and Foldable can introduce non-determinism
      and because of typeclass overloading it's implicit and not
      obvious at the call site. This removes the instances, so that
      they can't accidentally be used.
      
      Test Plan: ./validate
      
      Reviewers: austin, goldfire, bgamari, simonmar, simonpj
      
      Reviewed By: simonpj
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2190
      
      GHC Trac Issues: #4012
      7e28e47c
  14. 01 May, 2016 1 commit
  15. 28 Apr, 2016 3 commits
    • niteria's avatar
      Remove unused foldFsEnv · 6e195f4f
      niteria authored
      foldFsEnv is nondeterministic in the general case and since it's
      unused we can just remove it.
      6e195f4f
    • niteria's avatar
      Kill mapUniqSet · 73129231
      niteria authored
      Note [Unsound mapUniqSet] explains why it got removed.
      
      Test Plan: build ghc
      
      Reviewers: simonpj, austin, bgamari
      
      Reviewed By: bgamari
      
      Subscribers: thomie, simonmar
      
      Differential Revision: https://phabricator.haskell.org/D2152
      73129231
    • niteria's avatar
      Add uniqSetAny and uniqSetAll and use them · 3c426b05
      niteria authored
      There are couple of places where we do `foldUniqSet` just to
      compute `any` or `all`. `foldUniqSet` is non-deterministic in the
      general case and `any` and `all` also read nicer.
      
      Test Plan: ./validate
      
      Reviewers: simonmar, goldfire, simonpj, bgamari, austin
      
      Reviewed By: simonpj
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2156
      
      GHC Trac Issues: #4012
      3c426b05
  16. 26 Apr, 2016 1 commit
    • niteria's avatar
      Kill varSetElemsWellScoped in quantifyTyVars · c9bcaf31
      niteria authored
      varSetElemsWellScoped introduces unnecessary non-determinism in
      inferred type signatures.
      Removing this instance required changing the representation of
      TcDepVars to use deterministic sets.
      This is the last occurence of varSetElemsWellScoped, allowing me to
      finally remove it.
      
      Test Plan:
      ./validate
      I will update the expected outputs when commiting, some reordering
      of type variables in types is expected.
      
      Reviewers: goldfire, simonpj, austin, bgamari
      
      Reviewed By: simonpj
      
      Subscribers: thomie, simonmar
      
      Differential Revision: https://phabricator.haskell.org/D2135
      
      GHC Trac Issues: #4012
      c9bcaf31
  17. 22 Apr, 2016 1 commit
    • niteria's avatar
      Make benign non-determinism in pretty-printing more obvious · 0f96686b
      niteria authored
      This change takes us one step closer to being able to remove
      `varSetElemsWellScoped`. The end goal is to make every source
      of non-determinism obvious at the source level, so that when
      we achieve determinism it doesn't get broken accidentally.
      
      Test Plan: compile GHC
      
      Reviewers: simonmar, goldfire, simonpj, austin, bgamari
      
      Reviewed By: simonpj
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2123
      
      GHC Trac Issues: #4012
      0f96686b
  18. 20 Apr, 2016 1 commit
    • niteria's avatar
      Rename FV related functions · 2e33320a
      niteria authored
      This is from Simon's suggestion:
      
      * `tyCoVarsOfTypesAcc` is a terrible name for a function with a
        perfectly decent type `[Type] -> FV`. Maybe `tyCoFVsOfTypes`?
        Similarly others
      
      * `runFVList` is also terrible, but also has a decent type.
        Maybe just `fvVarList` (and `fvVarSet` for `runFVSet`).
      
      * `someVars` could be `mkFVs :: [Var] -> FV`.
      2e33320a
  19. 15 Apr, 2016 1 commit
  20. 06 Apr, 2016 1 commit
  21. 28 Mar, 2016 1 commit
    • Herbert Valerio Riedel's avatar
      Scrap DEC OSF/1 support · f911358b
      Herbert Valerio Riedel authored
      DEC OSF/1 (aka Tru64 UNIX) has been discontinued a few years ago already[1].
      
      This removes the undoubtedly bitrotten support for `OSOsf3 :: OS` from GHC's
      code-base.
      
      Support for `ArchAlpha :: Arch` may be removed at some later point, as there
      may still be users out there running a more or less recent Linux/alpha
      distribution on their more-than-a-decade old Alpha hardware...
      
       [1]: https://en.wikipedia.org/wiki/Tru64_UNIX
      f911358b
  22. 25 Mar, 2016 1 commit
  23. 24 Mar, 2016 1 commit
    • Ben Gamari's avatar
      ErrUtils: Add timings to compiler phases · 8048d51b
      Ben Gamari authored
      This adds timings and allocation figures to the compiler's output when
      run with `-v2` in an effort to ease performance analysis.
      
      Todo:
        * Documentation
        * Where else should we add these?
        * Perhaps we should remove some of the now-arguably-redundant
          `showPass` occurrences where they are
        * Must we force more?
        * Perhaps we should place this behind a `-ftimings` instead of `-v2`
      
      Test Plan: `ghc -v2 Test.hs`, look at the output
      
      Reviewers: hvr, goldfire, simonmar, austin
      
      Reviewed By: simonmar
      
      Subscribers: angerman, michalt, niteria, ezyang, thomie
      
      Differential Revision: https://phabricator.haskell.org/D1959
      8048d51b
  24. 11 Mar, 2016 1 commit
  25. 04 Mar, 2016 1 commit
  26. 24 Feb, 2016 1 commit
    • eir@cis.upenn.edu's avatar
      Address #11471 by putting RuntimeRep in kinds. · d8c64e86
      eir@cis.upenn.edu authored
      See Note [TYPE] in TysPrim. There are still some outstanding
      pieces in #11471 though, so this doesn't actually nail the bug.
      
      This commit also contains a few performance improvements:
      
      * Short-cut equality checking of nullary type syns
      
      * Compare types before kinds in eqType
      
      * INLINE coreViewOneStarKind
      
      * Store tycon binders separately from kinds.
      
      This resulted in a ~10% performance improvement in compiling
      the Cabal package. No change in functionality other than
      performance. (This affects the interface file format, though.)
      
      This commit updates the haddock submodule.
      d8c64e86
  27. 17 Feb, 2016 1 commit
    • Ryan Scott's avatar
      Remove superfluous code when deriving Foldable/Traversable · a82956df
      Ryan Scott authored
      Currently, `-XDeriveFoldable` and `-XDeriveTraversable` generate
      unnecessary `mempty` and `pure` expressions when it traverses of an
      argument of a constructor whose type does not mention the last type
      parameter. Not only is this inefficient, but it prevents `Traversable`
      from being derivable for datatypes with unlifted arguments (see
      Trac #11174).
      
      The solution to this problem is to adopt a slight change to the
      algorithms for `-XDeriveFoldable` and `-XDeriveTraversable`, which is
      described in [this wiki
      page](https://ghc.haskell.org/trac/ghc/wiki/Commentary/Compiler/DeriveFu
      nctor#Proposal:alternativestrategyforderivingFoldableandTraversable).
      The wiki page also describes why we don't apply the same changes to the
      algorithm for `-XDeriveFunctor`.
      
      This is techincally a breaking change for users of `-XDeriveFoldable`
      and `-XDeriveTraversable`, since if someone was using a law-breaking
      `Monoid` instance with a derived `Foldable` instance (i.e., one where `x
      <> mempty` does not equal `x`) or a law-breaking `Applicative` instance
      with a derived `Traversable` instance, then the new generated code could
      result in different behavior. I suspect the number of scenarios like
      this is very small, and the onus really should be on those users to fix
      up their `Monoid`/`Applicative` instances.
      
      Fixes #11174.
      
      Test Plan: ./validate
      
      Reviewers: hvr, simonpj, austin, bgamari
      
      Reviewed By: simonpj, bgamari
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D1908
      
      GHC Trac Issues: #11174
      a82956df
  28. 09 Feb, 2016 1 commit
  29. 02 Feb, 2016 1 commit
    • Simon Marlow's avatar
      Remote GHCi: parallelise BCO serialization · c996db5b
      Simon Marlow authored
      Summary:
      Serialization of BCOs is slow, but we can parallelise it when using
      ghci -j<n>.  It parallelises nicely, saving multiple seconds off the
      link time in a large example I have.
      
      Test Plan:
      * validate
      * `ghci -fexternal-interpreter` in `nofib/real/anna`
      
      Reviewers: niteria, bgamari, ezyang, austin, hvr, erikd
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D1877
      
      GHC Trac Issues: #11100
      c996db5b
  30. 01 Feb, 2016 1 commit
  31. 27 Jan, 2016 1 commit
    • eir@cis.upenn.edu's avatar
      Refactor the typechecker to use ExpTypes. · 00cbbab3
      eir@cis.upenn.edu authored
      The idea here is described in [wiki:Typechecker]. Briefly,
      this refactor keeps solid track of "synthesis" mode vs
      "checking" in GHC's bidirectional type-checking algorithm.
      When in synthesis mode, the expected type is just an IORef
      to write to.
      
      In addition, this patch does a significant reworking of
      RebindableSyntax, allowing much more freedom in the types
      of the rebindable operators. For example, we can now have
      `negate :: Int -> Bool` and
      `(>>=) :: m a -> (forall x. a x -> m b) -> m b`. The magic
      is in tcSyntaxOp.
      
      This addresses tickets #11397, #11452, and #11458.
      
      Tests:
        typecheck/should_compile/{RebindHR,RebindNegate,T11397,T11458}
        th/T11452
      00cbbab3
  32. 19 Jan, 2016 1 commit
    • niteria's avatar
      Check InScopeSet in substTy and provide substTyUnchecked · 9d33adb6
      niteria authored
      This adds sanity checks to `substTy` that implement:
      
      > when calling substTy subst ty it should be the case that the in-scope
      > set in the substitution is a superset of
      > * The free vars of the range of the substitution
      > * The free vars of ty minus the domain of the substitution
      
      and replaces violators with unchecked version. The violators were found
      by running the GHC test suite.
      
      This ensures that I can work on this incrementally and that what I fix won't
      be undone by some other change.
      
      It also includes a couple of fixes that I've already done.
      
      Test Plan: ./validate
      
      Reviewers: simonmar, goldfire, simonpj, austin, bgamari
      
      Reviewed By: simonpj, bgamari
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D1792
      
      GHC Trac Issues: #11371
      9d33adb6