1. 29 Aug, 2017 16 commits
    • Tamar Christina's avatar
      Fix decomposition error on Windows · 3c6b2fc3
      Tamar Christina authored
      Summary:
      Fix the path decomposition error that occurs when the Symlink resolver
      fails. `Win32.try` throws an exception, so catch it and assume the path
      isn't a symlink to use the old behavior.
      
      Test Plan: ./validate
      
      Reviewers: austin, bgamari
      
      Reviewed By: bgamari
      
      Subscribers: rwbarton, thomie
      
      GHC Trac Issues: #14159
      
      Differential Revision: https://phabricator.haskell.org/D3891
      3c6b2fc3
    • Ryan Scott's avatar
      Refactor type family instance abstract syntax declarations · 895a7650
      Ryan Scott authored
      This implements @simonpj's suggested refactoring of the abstract syntax
      for type/data family instances (from
      https://ghc.haskell.org/trac/ghc/ticket/14131#comment:9). This combines
      the previously separate `TyFamEqn` and `DataFamInstDecl` types into a
      single `FamEqn` datatype. This also factors the `HsImplicitBndrs` out of
      `HsTyPats` in favor of putting them just outside of `FamEqn` (as opposed
      to before, where all of the implicit binders were embedded inside of
      `TyFamEqn`/`DataFamInstDecl`). Finally, along the way I noticed that
      `dfid_fvs` and `tfid_fvs` were completely unused, so I removed them.
      
      Aside from some changes in parser test output, there is no change in
      behavior.
      
      Requires a Haddock submodule commit from my fork (at
      https://github.com/RyanGlScott/haddock/commit/815d2deb9c0222c916becccf84
      64b740c26255fd)
      
      Test Plan: ./validate
      
      Reviewers: simonpj, austin, goldfire, bgamari, alanz
      
      Reviewed By: bgamari
      
      Subscribers: mpickering, goldfire, rwbarton, thomie, simonpj
      
      GHC Trac Issues: #14131
      
      Differential Revision: https://phabricator.haskell.org/D3881
      895a7650
    • Tamar Christina's avatar
      Remove dll-split. · 5266ab90
      Tamar Christina authored
      This patch removes dll-split from the code base, the reason is dll-split
      no longer makes any sense. It was designed to split a dll in two, but we
      now already have many more symbols than would fit inside two dlls. So we
      need a third one. This means there's no point in having to maintain this
      list as it'll never work anyway and the solution isn't scalable.
      
      Test Plan: ./validate
      
      Reviewers: austin, bgamari
      
      Reviewed By: bgamari
      
      Subscribers: rwbarton, thomie, #ghc_windows_task_force
      
      GHC Trac Issues: #5987
      
      Differential Revision: https://phabricator.haskell.org/D3882
      5266ab90
    • Ben Gamari's avatar
      desugar: Ensure that a module's dep_orphs doesn't contain itself · db3a8e16
      Ben Gamari authored
      Consider that we have two modules, A and B, both with hs-boot files,
      
        * A.hs contains a SOURCE import of B
        * B.hs-boot contains a SOURCE import of A
        * A.hs-boot declares an orphan instance
        * A.hs defines the orphan instance
      
      In this case, B's dep_orphs will contain A due to its SOURCE import of
      A.  Consequently, A will contain itself in its imp_orphs due to its
      import of B.  This fact would end up being recorded in A's interface
      file. This would then break the invariant asserted by calculateAvails
      that a module does not itself in its dep_orphs. This was the cause
      of #14128.
      
      The solution is to remove self-references from imp_orphs when
      constructing dep_orphs; we already did a similar thing for dep_mods. I
      believe we should do the same for dep_finsts, although I'm treating this
      as a separate bug.
      
      Reviewers: austin
      
      Subscribers: rwbarton, thomie
      
      Differential Revision: https://phabricator.haskell.org/D3892
      db3a8e16
    • Ben Gamari's avatar
      testsuite: Add test for #14128 · 248ad303
      Ben Gamari authored
      Reviewers: austin, goldfire
      
      Subscribers: rwbarton, thomie
      
      GHC Trac Issues: #14128
      
      Differential Revision: https://phabricator.haskell.org/D3890
      248ad303
    • Simon Peyton Jones's avatar
      Add HasDebugStack for typeKind · aed7d431
      Simon Peyton Jones authored
      typeKind can fail, and it's called all over the place, so
      it's helpful to know where
      aed7d431
    • Simon Peyton Jones's avatar
      Small refactor of getRuntimeRep · a6c448b4
      Simon Peyton Jones authored
      Instead of using a string argument, use HasDebugCallStack.
      (Oddly, some functions were using both!)
      
      Plus, use getRuntimeRep rather than getRuntimeRep_maybe when
      if the caller panics on Nothing. Less code, and a better debug
      stack.
      a6c448b4
    • Simon Peyton Jones's avatar
      8eead4de
    • Simon Peyton Jones's avatar
      Use a well-kinded substitution to instantiate · 4455c86d
      Simon Peyton Jones authored
      In tcDataConPat we were creating an ill-kinded substitution
      -- or at least one that is well kinded only after you have solved
      other equalities.  THat led to a crash, because the instantiated
      data con type was ill-kinded.
      
      This patch guarantees that the instantiating substitution is
      well-kinded.
      
      Fixed Trac #14154
      4455c86d
    • Simon Peyton Jones's avatar
      Small refactoring of meta-tyvar cloning · 86e6a5f2
      Simon Peyton Jones authored
      No change in behaviour.
      86e6a5f2
    • Simon Peyton Jones's avatar
      Refactor bindHsQTyVars and friends · 0257dacf
      Simon Peyton Jones authored
      This work was triggered by Trac #13738, which revealed to me that
      the code RnTypes.bindHsQTyVars and bindLHsTyVarBndrs was a huge
      tangled mess -- and outright wrong on occasion as the ticket showed.
      
      The big problem was that bindLHsTyVarBndrs (which is invoked at every
      HsForAll, including nested higher rank ones) was attempting to bind
      implicit kind variables, which it has absolutely no busineess doing.
      Imlicit kind quantification is done at the outside only, in fact
      precisely where we have HsImplicitBndrs or LHsQTyVars (which also
      has implicit binders).
      
      Achieving this move was surprisingly hard, because more and more
      barnacles had accreted aroud the original mistake.  It's much
      much better now.
      
      Summary of changes.  Almost all the action is in RnTypes.
      
      * Implicit kind variables are bound only by
        - By bindHsQTyVars, which deals with LHsQTyVars
        - By rnImplicitBndrs, which deals with HsImplicitBndrs
      
      * bindLHsTyVarBndrs, and bindLHsTyVarBndr are radically simplified.
        They simply does far less, and have lots their forest of
        incomprehensible accumulating parameters.  (To be fair, some of
        the code in bindLHsTyVarBndrs just moved to bindHsQTyVars, but
        in much more perspicuous form.)
      
      * The code that checks if a variable appears in both a kind and
        a type (triggering RnTypes.mixedVarsErr) was bizarre.  E.g.
        we had this in RnTypes.extract_hs_tv_bndrs
             ; check_for_mixed_vars bndr_kvs acc_tvs
             ; check_for_mixed_vars bndr_kvs body_tvs
             ; check_for_mixed_vars body_tvs acc_kvs
             ; check_for_mixed_vars body_kvs acc_tvs
             ; check_for_mixed_vars locals body_kvs
        I cleaned all this up; now we check for mixed use at binding
        sites only.
      
      * Checks for "Variable used as a kind before being bound", like
           data T (a :: k) k = rhs
        now just show up straightforwardly as "k is not in scope".
        See Note [Kind variable ordering]
      
      * There are some knock-on simplifications in RnSource.
      0257dacf
    • Simon Peyton Jones's avatar
      Add TcRnMonad.unlessXOptM · 6f050d9c
      Simon Peyton Jones authored
      This usefully joins whenXOptM; there are probably lots of places
      we should use it!
      
      This patch does not use new new function at all; but it's preparing
      for an upcoming patch when I do use it.
      6f050d9c
    • Simon Peyton Jones's avatar
      A bit more -ddump-tc tracing · 547e4c03
      Simon Peyton Jones authored
      547e4c03
    • Simon Peyton Jones's avatar
      Better debug-printing for Outputable TyConBinder · 8834d482
      Simon Peyton Jones authored
      Anon and Required were printed the same :-(.  This is only for
      debug printing, so I switched to a slightly more verbose and
      explicit format
      8834d482
    • Simon Peyton Jones's avatar
      Comments only · 6e0e0b0e
      Simon Peyton Jones authored
      Better comment on con_qvars in ConDecl
      6e0e0b0e
    • David Feuer's avatar
      Make parsed AST dump output lazily · 29da01e0
      David Feuer authored
      Previously, `showAstData` produced a `String`. That `String` would
      then be converted to a `Doc` using `text` to implement
      `-ddump-parsed-ast`. But rendering `text` calculates the length
      of the `String` before doing anything else. Since the AST can be
      very large, this was bad: the whole dump string (potentially hundreds
      of millions of `Char`s) was accumulated in memory.
      
      Now, `showAstData` produces a `Doc` directly, which seems to work
      a lot better. As an extra bonus, the code is simpler and cleaner.
      The formatting has changed a bit, as the previous ad hoc approach
      didn't really match the pretty printer too well. If someone cares
      enough to request adjustments, we can surely make them.
      
      Reviewers: austin, bgamari, mpickering, alanz
      
      Reviewed By: bgamari
      
      Subscribers: mpickering, rwbarton, thomie
      
      GHC Trac Issues: #14161
      
      Differential Revision: https://phabricator.haskell.org/D3894
      29da01e0
  2. 28 Aug, 2017 2 commits
  3. 26 Aug, 2017 1 commit
  4. 25 Aug, 2017 11 commits
    • Ben Gamari's avatar
      Rip out mkUserGuidePart · 8f19c65c
      Ben Gamari authored
      Reviewers: austin, hvr
      
      Subscribers: rwbarton, thomie, erikd
      
      Differential Revision: https://phabricator.haskell.org/D3886
      8f19c65c
    • Ben Gamari's avatar
      rts: Fix ASSERTs with space before opening paren · 76e59a27
      Ben Gamari authored
      Reviewers: austin, erikd, simonmar
      
      Subscribers: rwbarton, thomie
      
      Differential Revision: https://phabricator.haskell.org/D3885
      76e59a27
    • Ben Gamari's avatar
      rts: Fix references to Note [BFD import library] · 80ccea85
      Ben Gamari authored
      Reviewers: austin, erikd, simonmar
      
      Subscribers: rwbarton, thomie
      
      Differential Revision: https://phabricator.haskell.org/D3884
      80ccea85
    • Ben Gamari's avatar
      rts: Fix warnings on aarch64 and clean up style · f135fb2a
      Ben Gamari authored
      Reviewers: austin, erikd, simonmar
      
      Subscribers: rwbarton, thomie
      
      Differential Revision: https://phabricator.haskell.org/D3877
      f135fb2a
    • Ben Gamari's avatar
      Add strict variant of iterate · a67b66e6
      Ben Gamari authored
      Summary: This closes the nearly-eight-year-old #3474.
      
      Test Plan: Validate
      
      Reviewers: RyanGlScott, austin, hvr
      
      Subscribers: rwbarton, thomie
      
      GHC Trac Issues: #3474
      
      Differential Revision: https://phabricator.haskell.org/D3870
      a67b66e6
    • Simon Peyton Jones's avatar
    • Simon Peyton Jones's avatar
      Don't do the RhsCtxt thing for join points · 8649535c
      Simon Peyton Jones authored
      This minor change fixes Trac #14137.
      
      It is described in Note [Join point RHSs] in OccurAnal
      8649535c
    • Simon Peyton Jones's avatar
      Refactor the Mighty Simplifier · 33452dfc
      Simon Peyton Jones authored
      Triggered by #12150, and the knock-on effects of join points, I did a
      major refactoring of the Simplifier.  This is a big patch that change
      a lot of Simplify.hs: I did a lot of other re-organisation.
      
      The main event
      ~~~~~~~~~~~~~~
      Since the dawn of time we have had
        simplExpr :: SimplEnv -> InExpr -> SimplCont
                  -> SimplM (SimplEnv, OutExpr)
      
      What's that SimplEnv in the result?  When simplifying an expression the
      simplifier add floated let-bindings to the SimplEnv, extending the
      in-scope set appropriately, and hence needs to resturn the SimplEnv at
      the end.  The mode, flags, substitution in the returned SimplEnv were
      all irrelevant: it was just the floating bindings.
      
      It's strange to accumulate part of the /result/ in the /environment/
      argument!  And indeed its leads to all manner of mysterious calls to
      zapFloats and transferring of floats from one SimplEnv to another.
      It got worse with join points, so I finally bit the bullet and refactored.
      Now we have
        simplExpr :: SimplEnv -> InExpr -> SimplCont
                  -> SimplM (SimplFloats, OutExpr)
        -- See Note [The big picture]
      and the SimplEnv no longer has floats in it.  The code is no shorter,
      but it /is/ easier to understand.
      
      Main changes
      
      * Remove seLetFloats field from SimplEnv
      
      * Define new data type SimplFloats, and functions over it
      
      * Change the types of simplExpr, simplBind, and their many variants,
        to follow the above plan
      
      Bottoming bindings
      ~~~~~~~~~~~~~~~~~~
      I made one other significant change in SimplUtils (not just refactoring),
      related to Trac #12150 comment:16.  Given
        x = <rhs>
      where <rhs> turns out to be a bottoming expression, propagate that
      information to x's IdInfo immediately.  That's always good, because
      it makes x be inlined less (we don't inline bottoming things), and
      it allows (case x of ...) to drop the dead alterantives immediately.
      Moreover, we are doing the analysis anyway, in tryEtaExpandRhs, which
      calls CoreArity.findRhsArity, which already does simple bottom analysis.
      So we are generating the information; all we need do is to atach the
      bottoming info to the IdInfo.
      
      See Note [Bottoming bindings]
      
      Smaller refactoring
      ~~~~~~~~~~~~~~~~~~~
      * Rename SimplifierMode to SimplMode
      * Put DynFlags as a new field in SimplMode, to make fewer
        monadic calls to getDynFlags.
      * Move the code in addPolyBind into abstractFloats
      * Move the "don't eta-expand join points" into tryEtaExpandRhs
      33452dfc
    • Simon Peyton Jones's avatar
      Bottoming expressions should not be expandable · 407c11b8
      Simon Peyton Jones authored
      This patch changes isExpandableApp and isWorkFreeApp to respond
      False to bottoming applications.  I found that if we had
      
        x = undefined <dict-expr>
      
      then prepareRhs was ANF'ing it to
      
        d = <dict-expr>
        x = undefined d
      
      which is stupid (no gain); and worse it made the simplifier iterate
      indefinitely.  It showed up when I started marking 'x' as a bottoming
      Id more aggresssively than before; but it's been a lurking bug for
      ages.
      
      It was convenient to make isWorkFreeApp also return False for
      bottoming applications, and I see no reason not to do so.
      
      That leaves isCheapApp.  It currently replies True to bottoming
      applications, but I don't see why that's good..  Something to try
      later.
      407c11b8
    • Simon Peyton Jones's avatar
      Restrict exprOkForSpeculation/case to unlifted types · a0b7b100
      Simon Peyton Jones authored
      Consider
        case x of y
          DEFAULT -> let v::Int# = case y of
                                     True  -> e1
                                     False -> e2
                      in ...
      
      Previously this would have been ok-for-speculation because
      y is evaluated.  But the binder-swap done
      by SetLevels would transform the inner alternative to
           DEFAULT -> let v::Int# = case x of { ... }
                      in ...)
      which does /not/ satisfy the let/app invariant, because x is
      not evaluated.
      
      I don't know why this has never bitten us before, but it began
      to bite when I did upcoming refactoring of the Simplifier.
      
      So this patch narrows exprOkForSpeculation to only work for
      /unlifted/ cases.
      
      To make this work I had to make exprOkForSpeculation non-polymorphic
      in the binder type, which has a little knock-on for is use in
      SetLevels.
      
      (It's annoying that we need to handle cases at all, but see
       Note [exprOkForSpeculation: case expressions])
      a0b7b100
    • Ben Gamari's avatar
      CNF: Implement compaction for small pointer arrays · 5f3d2d3b
      Ben Gamari authored
      Test Plan: Validate
      
      Reviewers: austin, erikd, simonmar, dfeuer
      
      Reviewed By: dfeuer
      
      Subscribers: rwbarton, andrewthad, thomie, dfeuer
      
      GHC Trac Issues: #13860, #13857
      
      Differential Revision: https://phabricator.haskell.org/D3888
      5f3d2d3b
  5. 24 Aug, 2017 4 commits
  6. 22 Aug, 2017 6 commits