1. 29 Aug, 2017 12 commits
    • 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
    • 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
    • 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
    • Simon Peyton Jones's avatar
    • 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
      Fixed Trac #14154
    • Simon Peyton Jones's avatar
      Small refactoring of meta-tyvar cloning · 86e6a5f2
      Simon Peyton Jones authored
      No change in behaviour.
    • 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.
    • 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.
    • Simon Peyton Jones's avatar
      A bit more -ddump-tc tracing · 547e4c03
      Simon Peyton Jones authored
    • 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
    • Simon Peyton Jones's avatar
      Comments only · 6e0e0b0e
      Simon Peyton Jones authored
      Better comment on con_qvars in ConDecl
    • 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
  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
    • 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
    • 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
    • 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
    • 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
    • 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
    • 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
    • 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
      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
    • Simon Peyton Jones's avatar
      Restrict exprOkForSpeculation/case to unlifted types · a0b7b100
      Simon Peyton Jones authored
        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
      (It's annoying that we need to handle cases at all, but see
       Note [exprOkForSpeculation: case expressions])
    • 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
  5. 24 Aug, 2017 4 commits
  6. 22 Aug, 2017 10 commits