1. 21 Feb, 2020 1 commit
    • Simon Peyton Jones's avatar
      Re-implement unsafe coercions in terms of unsafe equality proofs · 74ad75e8
      Simon Peyton Jones authored
      (Commit message written by Omer, most of the code is written by Simon
      and Richard)
      
      See Note [Implementing unsafeCoerce] for how unsafe equality proofs and
      the new unsafeCoerce# are implemented.
      
      New notes added:
      
      - [Checking for levity polymorphism] in CoreLint.hs
      - [Implementing unsafeCoerce] in base/Unsafe/Coerce.hs
      - [Patching magic definitions] in Desugar.hs
      - [Wiring in unsafeCoerce#] in Desugar.hs
      
      Only breaking change in this patch is unsafeCoerce# is not exported from
      GHC.Exts, instead of GHC.Prim.
      
      Fixes #17443
      Fixes #16893
      
      NoFib
      -----
      
      --------------------------------------------------------------------------------
              Program           Size    Allocs    Instrs     Reads    Writes
      --------------------------------------------------------------------------------
                   CS          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  CSD          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                   FS          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                    S          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                   VS          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  VSD          -0.1%      0.0%     -0.0%     -0.0%     -0.1%
                  VSM          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 anna          -0.0%      0.0%     -0.0%     -0.0%     -0.0%
                 ansi          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 atom          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               awards          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               banner          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
           bernouilli          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
         binary-trees          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                boyer          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               boyer2          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 bspt          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
            cacheprof          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
             calendar          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
             cichelli          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
              circsim          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
             clausify          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
        comp_lab_zift          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
             compress          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
            compress2          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
          constraints          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
         cryptarithm1          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
         cryptarithm2          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  cse          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
         digits-of-e1          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
         digits-of-e2          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               dom-lt          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                eliza          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                event          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
          exact-reals          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               exp3_8          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               expert          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
       fannkuch-redux          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                fasta          -0.1%      0.0%     -0.5%     -0.3%     -0.4%
                  fem          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  fft          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 fft2          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
             fibheaps          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 fish          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                fluid          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               fulsom          -0.1%      0.0%     +0.0%     +0.0%     +0.0%
               gamteb          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  gcd          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
          gen_regexps          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               genfft          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                   gg          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 grep          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               hidden          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  hpg          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  ida          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                infer          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
              integer          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
            integrate          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
         k-nucleotide          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                kahan          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
              knights          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               lambda          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
           last-piece          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 lcss          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 life          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 lift          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               linear          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
            listcompr          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
             listcopy          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
             maillist          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               mandel          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
              mandel2          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 mate          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
              minimax          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
              mkhprog          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
           multiplier          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               n-body          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
             nucleic2          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 para          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
            paraffins          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               parser          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
              parstof          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  pic          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
             pidigits          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                power          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               pretty          -0.1%      0.0%     -0.1%     -0.1%     -0.1%
               primes          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
            primetest          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               prolog          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               puzzle          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               queens          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
              reptile          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
      reverse-complem          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
              rewrite          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 rfib          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  rsa          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  scc          -0.1%      0.0%     -0.1%     -0.1%     -0.1%
                sched          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  scs          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               simple          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                solid          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
              sorting          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
        spectral-norm          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               sphere          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
               symalg          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                  tak          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
            transform          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
             treejoin          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
            typecheck          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
              veritas          -0.0%      0.0%     -0.0%     -0.0%     -0.0%
                 wang          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
            wave4main          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
         wheel-sieve1          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
         wheel-sieve2          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
                 x2n1          -0.1%      0.0%     -0.0%     -0.0%     -0.0%
      --------------------------------------------------------------------------------
                  Min          -0.1%      0.0%     -0.5%     -0.3%     -0.4%
                  Max          -0.0%      0.0%     +0.0%     +0.0%     +0.0%
       Geometric Mean          -0.1%     -0.0%     -0.0%     -0.0%     -0.0%
      
      Test changes
      ------------
      
      - break006 is marked as broken, see #17833
      - The compiler allocates less when building T14683 (an unsafeCoerce#-
        heavy happy-generated code) on 64-platforms. Allocates more on 32-bit
        platforms.
      - Rest of the increases are tiny amounts (still enough to pass the
        threshold) in micro-benchmarks. I briefly looked at each one in a
        profiling build: most of the increased allocations seem to be because
        of random changes in the generated code.
      
      Metric Decrease:
          T14683
      
      Metric Increase:
          T12150
          T12234
          T12425
          T13035
          T14683
          T5837
          T6048
      Co-Authored-By: Richard Eisenberg's avatarRichard Eisenberg <rae@cs.brynmawr.edu>
      Co-Authored-By: Ömer Sinan Ağacan's avatarÖmer Sinan Ağacan <omeragacan@gmail.com>
      74ad75e8
  2. 25 Jan, 2020 1 commit
  3. 06 Jan, 2020 1 commit
  4. 04 Dec, 2019 1 commit
    • Ben Gamari's avatar
      Simplify uniqAway · 78b67ad0
      Ben Gamari authored
      This does two things:
      
       * Eliminate all uses of Unique.deriveUnique, which was quite easy to
         mis-use and extremely subtle.
      
       * Rename the previous "derived unique" notion to "local unique". This
         is possible because the only places where `uniqAway` can be safely
         used are those where local uniqueness (with respect to some
         InScopeSet) is sufficient.
      
       * Rework the implementation of VarEnv.uniqAway, as discussed in #17462.
         This should make the operation significantly more efficient than its
         previous iterative implementation..
      
      Metric Decrease:
          T9872c
          T12227
          T9233
          T14683
          T5030
          T12545
          hie002
      
      Metric Increase:
          T9961
      78b67ad0
  5. 26 Jun, 2019 1 commit
    • Ben Gamari's avatar
      Don't eta-expand unsaturated primops · cac8dc9f
      Ben Gamari authored
      Previously, as described in Note [Primop wrappers], `hasNoBinding` would
      return False in the case of `PrimOpId`s. This would result in eta
      expansion of unsaturated primop applications during CorePrep. Not only
      did this expansion result in unnecessary allocations, but it also meant
      lead to rather nasty inconsistencies between the CAFfy-ness
      determinations made by TidyPgm and CorePrep.
      
      This fixes #16846.
      cac8dc9f
  6. 25 Mar, 2019 1 commit
    • Takenobu Tani's avatar
      Update Wiki URLs to point to GitLab · 3769e3a8
      Takenobu Tani authored
      This moves all URL references to Trac Wiki to their corresponding
      GitLab counterparts.
      
      This substitution is classified as follows:
      
      1. Automated substitution using sed with Ben's mapping rule [1]
          Old: ghc.haskell.org/trac/ghc/wiki/XxxYyy...
          New: gitlab.haskell.org/ghc/ghc/wikis/xxx-yyy...
      
      2. Manual substitution for URLs containing `#` index
          Old: ghc.haskell.org/trac/ghc/wiki/XxxYyy...#Zzz
          New: gitlab.haskell.org/ghc/ghc/wikis/xxx-yyy...#zzz
      
      3. Manual substitution for strings starting with `Commentary`
          Old: Commentary/XxxYyy...
          New: commentary/xxx-yyy...
      
      See also !539
      
      [1]: https://gitlab.haskell.org/bgamari/gitlab-migration/blob/master/wiki-mapping.json
      3769e3a8
  7. 02 Sep, 2018 1 commit
  8. 07 Jun, 2018 1 commit
  9. 02 Jun, 2018 1 commit
    • Ben Gamari's avatar
      vectorise: Put it out of its misery · faee23bb
      Ben Gamari authored
      Poor DPH and its vectoriser have long been languishing; sadly it seems there is
      little chance that the effort will be rekindled. Every few years we discuss
      what to do with this mass of code and at least once we have agreed that it
      should be archived on a branch and removed from `master`. Here we do just that,
      eliminating heaps of dead code in the process.
      
      Here we drop the ParallelArrays extension, the vectoriser, and the `vector` and
      `primitive` submodules.
      
      Test Plan: Validate
      
      Reviewers: simonpj, simonmar, hvr, goldfire, alanz
      
      Reviewed By: simonmar
      
      Subscribers: goldfire, rwbarton, thomie, mpickering, carter
      
      Differential Revision: https://phabricator.haskell.org/D4761
      faee23bb
  10. 01 Feb, 2018 1 commit
    • Simon Peyton Jones's avatar
      Experiment with eliminating the younger tyvar · 618a805b
      Simon Peyton Jones authored
      This patch is comments only, plus a minor refactor that
      does not change behaviour.
      
      It just records an idea I had for reducing kick-out in the type
      constraint-solver.
      
      See Note [Eliminate younger unification variables] in TcUnify.
      
      Sadly, it didn't improve perf, so I've put it aside, leaving
      some breadcrumbs for future generations of GHC hackers.
      618a805b
  11. 29 Oct, 2017 1 commit
    • Joachim Breitner's avatar
      Implement a dedicated exitfication pass #14152 · 0e953da1
      Joachim Breitner authored
      The idea is described in #14152, and can be summarized: Float the exit
      path out of a joinrec, so that the simplifier can do more with it.
      See the test case for a nice example.
      
      The floating goes against what the simplifier usually does, hence we
      need to be careful not inline them back.
      
      The position of exitification in the pipeline was chosen after a small
      amount of experimentation, but may need to be improved. For example,
      exitification can allow rewrite rules to fire, but for that it would
      have to happen before the `simpl_phases`.
      
      Perf.haskell.org reports these nice performance wins:
      
          Nofib allocations
          fannkuch-redux    78446640  - 99.92%      64560
          k-nucleotide     109466384  - 91.32%    9502040
          simple            72424696  -  5.96%   68109560
      
          Nofib instruction counts
          fannkuch-redux  1744331636  -  3.86% 1676999519
          k-nucleotide    2318221965  -  6.30% 2172067260
          scs             1978470869  -  3.35% 1912263779
          simple           669858104  -  3.38%  647206739
          spectral-norm    186423292  -  5.37%  176411536
      
      Differential Revision: https://phabricator.haskell.org/D3903
      0e953da1
  12. 19 Sep, 2017 1 commit
    • Herbert Valerio Riedel's avatar
      compiler: introduce custom "GhcPrelude" Prelude · f63bc730
      Herbert Valerio Riedel authored
      This switches the compiler/ component to get compiled with
      -XNoImplicitPrelude and a `import GhcPrelude` is inserted in all
      modules.
      
      This is motivated by the upcoming "Prelude" re-export of
      `Semigroup((<>))` which would cause lots of name clashes in every
      modulewhich imports also `Outputable`
      
      Reviewers: austin, goldfire, bgamari, alanz, simonmar
      
      Reviewed By: bgamari
      
      Subscribers: goldfire, rwbarton, thomie, mpickering, bgamari
      
      Differential Revision: https://phabricator.haskell.org/D3989
      f63bc730
  13. 29 Mar, 2017 1 commit
    • Sergei Trofimovich's avatar
      unique: fix UNIQUE_BITS crosscompilation (Trac #13491) · 01b062ec
      Sergei Trofimovich authored
      The #13491 manifests best when we try to crosscompile
      from 32-bit (i386-linux) to 64-bit (powerpc64-linux)
      system:
          ./configure --target=powerpc64-unknown-linux-gnu
      
      The build fails at assembly time:
        "inplace/bin/ghc-stage1" ...  -c rts/StgStartup.cmm
          /tmp/ghc19687_0/ghc_4.s: Assembler messages:
      
          /tmp/ghc19687_0/ghc_4.s:11:0: error:
               Error: unknown pseudo-op: `.l'
             |
          11 | .L<\x00>4:
             | ^
      
      That happens because UNIQUE_BITS is defined in terms
      of WORD_SIZE_IN_BITS macro:
          #define UNIQUE_BITS (WORD_SIZE_IN_BITS - 8)
      
      WORD_SIZE_IN_BITS is 64 bits (equals to target value)
      while ghc-stage1 is still running on i386-linux
      
      The fix is to stop relying on target macros and use
      host's 'sizeof (HsInt)' and 'finiteBitSize' way to
      determine unique layout.
      Signed-off-by: default avatarSergei Trofimovich <slyfox@gentoo.org>
      
      Test Plan: build i386-to-powerpc64 crosscompiler
      
      Reviewers: rwbarton, austin, bgamari
      
      Reviewed By: bgamari
      
      Subscribers: RyanGlScott, thomie
      
      Differential Revision: https://phabricator.haskell.org/D3397
      01b062ec
  14. 17 Feb, 2017 1 commit
    • Simon Peyton Jones's avatar
      Honour -dsuppress-uniques more thoroughly · 8d401e50
      Simon Peyton Jones authored
      I found that tests
        parser/should_compile/DumpRenamedAst
      and friends were printing uniques, which makes the test fragile.
      But -dsuppress-uniques made no difference!  It turned out that
      pprName wasn't properly consulting Opt_SuppressUniques.
      
      This patch fixes the problem, and updates those three tests to
      use -dsuppress-uniques
      8d401e50
  15. 16 Dec, 2016 1 commit
  16. 15 Dec, 2016 1 commit
    • Ben Gamari's avatar
      UniqSupply: Use full range of machine word · 0d213c18
      Ben Gamari authored
      Currently uniques are 32-bits wide. 8 of these bits are for the unique
      class, leaving only 24 for the unique number itself. This seems
      dangerously small for a large project. Let's use the full range of the
      native machine word.
      
      We also add (now largely unnecessary) overflow check to ensure that the
      unique number doesn't overflow.
      
      Test Plan: Validate
      
      Reviewers: simonmar, austin, niteria
      
      Reviewed By: niteria
      
      Subscribers: mpickering, thomie
      
      Differential Revision: https://phabricator.haskell.org/D2844
      
      GHC Trac Issues: #12944
      0d213c18
  17. 14 Oct, 2016 2 commits
    • Ben Gamari's avatar
      Clean up handling of known-key Names in interface files · 34d933d6
      Ben Gamari authored
      Previously BinIface had some dedicated logic for handling tuple names in
      the symbol table. As it turns out, this logic was essentially dead code
      as it was superceded by the special handling of known-key things. Here
      we cull the tuple code-path and use the known-key codepath for all
      tuple-ish things.
      
      This had a surprising number of knock-on effects,
      
       * constraint tuple datacons had to be made known-key (previously they
         were not)
      
       * IfaceTopBndr was changed from being a synonym of OccName to a
         synonym of Name (since we now need to be able to deserialize Names
         directly from interface files)
      
       * the change to IfaceTopBndr complicated fingerprinting, since we need
         to ensure that we don't go looking for the fingerprint of the thing
         we are currently fingerprinting in the fingerprint environment (see
         notes in MkIface). Handling this required distinguishing between
         binding and non-binding Name occurrences in the Binary serializers.
      
       * the original name cache logic which previously lived in IfaceEnv has
         been moved to a new NameCache module
      
       * I ripped tuples and sums out of knownKeyNames since they introduce a
         very large number of entries. During interface file deserialization
         we use static functions (defined in the new KnownUniques module) to
         map from a Unique to a known-key Name (the Unique better correspond
         to a known-key name!) When we need to do an original name cache
         lookup we rely on the parser implemented in isBuiltInOcc_maybe.
      
       * HscMain.allKnownKeyNames was folded into PrelInfo.knownKeyNames.
      
       * Lots of comments were sprinkled about describing the new scheme.
      
      Updates haddock submodule.
      
      Test Plan: Validate
      
      Reviewers: niteria, simonpj, austin, hvr
      
      Reviewed By: simonpj
      
      Subscribers: simonmar, niteria, thomie
      
      Differential Revision: https://phabricator.haskell.org/D2467
      
      GHC Trac Issues: #12532, #12415
      34d933d6
    • Ben Gamari's avatar
      Unique: Simplify encoding of sum uniques · 1cccb646
      Ben Gamari authored
      The previous encoding was entropically a bit better, but harder to
      encode and decode. Now we just split up the integer part of the unique
      into a bitfield.
      
      Test Plan: Validate
      
      Reviewers: austin
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2468
      1cccb646
  18. 31 Aug, 2016 1 commit
  19. 05 Aug, 2016 1 commit
  20. 28 Jul, 2016 1 commit
  21. 21 Jul, 2016 2 commits
    • Ömer Sinan Ağacan's avatar
      Fix and document Unique generation for sum TyCon and DataCons · 8265c783
      Ömer Sinan Ağacan authored
      Test Plan: validate
      
      Reviewers: bgamari, austin
      
      Reviewed By: bgamari
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2420
      8265c783
    • Ömer Sinan Ağacan's avatar
      Implement unboxed sum primitive type · 714bebff
      Ömer Sinan Ağacan authored
      Summary:
      This patch implements primitive unboxed sum types, as described in
      https://ghc.haskell.org/trac/ghc/wiki/UnpackedSumTypes.
      
      Main changes are:
      
      - Add new syntax for unboxed sums types, terms and patterns. Hidden
        behind `-XUnboxedSums`.
      
      - Add unlifted unboxed sum type constructors and data constructors,
        extend type and pattern checkers and desugarer.
      
      - Add new RuntimeRep for unboxed sums.
      
      - Extend unarise pass to translate unboxed sums to unboxed tuples right
        before code generation.
      
      - Add `StgRubbishArg` to `StgArg`, and a new type `CmmArg` for better
        code generation when sum values are involved.
      
      - Add user manual section for unboxed sums.
      
      Some other changes:
      
      - Generalize `UbxTupleRep` to `MultiRep` and `UbxTupAlt` to
        `MultiValAlt` to be able to use those with both sums and tuples.
      
      - Don't use `tyConPrimRep` in `isVoidTy`: `tyConPrimRep` is really
        wrong, given an `Any` `TyCon`, there's no way to tell what its kind
        is, but `kindPrimRep` and in turn `tyConPrimRep` returns `PtrRep`.
      
      - Fix some bugs on the way: #12375.
      
      Not included in this patch:
      
      - Update Haddock for new the new unboxed sum syntax.
      
      - `TemplateHaskell` support is left as future work.
      
      For reviewers:
      
      - Front-end code is mostly trivial and adapted from unboxed tuple code
        for type checking, pattern checking, renaming, desugaring etc.
      
      - Main translation routines are in `RepType` and `UnariseStg`.
        Documentation in `UnariseStg` should be enough for understanding
        what's going on.
      
      Credits:
      
      - Johan Tibell wrote the initial front-end and interface file
        extensions.
      
      - Simon Peyton Jones reviewed this patch many times, wrote some code,
        and helped with debugging.
      
      Reviewers: bgamari, alanz, goldfire, RyanGlScott, simonpj, austin,
                 simonmar, hvr, erikd
      
      Reviewed By: simonpj
      
      Subscribers: Iceland_jack, ggreif, ezyang, RyanGlScott, goldfire,
                   thomie, mpickering
      
      Differential Revision: https://phabricator.haskell.org/D2259
      714bebff
  22. 30 Jun, 2016 1 commit
    • niteria's avatar
      Delete Ord Unique · fb6e2c7f
      niteria authored
      Ord Unique can be a source of invisible, accidental
      nondeterminism as explained in Note [No Ord for Unique].
      This removes it, leaving a note with rationale.
      
      It's unfortunate that I had to write Ord instances for
      codegen data structures by hand, but I believe that it's a
      right trade-off here.
      
      Test Plan: ./validate
      
      Reviewers: simonmar, austin, bgamari
      
      Reviewed By: simonmar
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2370
      
      GHC Trac Issues: #4012
      fb6e2c7f
  23. 10 May, 2016 1 commit
    • niteria's avatar
      Make simplifyInstanceContexts deterministic · b58b0e18
      niteria authored
      simplifyInstanceContexts used cmpType which is nondeterministic
      for canonicalising typeclass constraints in derived instances.
      Following changes make it deterministic as explained by the
      Note [Deterministic simplifyInstanceContexts].
      
      Test Plan: ./validate
      
      Reviewers: simonmar, goldfire, simonpj, austin, bgamari
      
      Reviewed By: simonpj
      
      Subscribers: thomie
      
      Differential Revision: https://phabricator.haskell.org/D2173
      
      GHC Trac Issues: #4012
      b58b0e18
  24. 16 Feb, 2016 1 commit
  25. 20 Jan, 2016 1 commit
    • Ben Gamari's avatar
      Rework derivation of type representations for wired-in things · 84b0ebed
      Ben Gamari authored
      Previously types defined by `GHC.Types` and `GHC.Prim` had their
      `Typeable` representations manually defined in `GHC.Typeable.Internals`.
      This was terrible, resulting in a great deal of boilerplate and a number
      of bugs due to missing or inconsistent representations (see #11120).
      
      Here we take a different tack, initially proposed by Richard Eisenberg:
      We wire-in the `Module`, `TrName`, and `TyCon` types, allowing them to
      be used in `GHC.Types`. We then allow the usual type representation
      generation logic to handle this module.
      
      `GHC.Prim`, on the other hand, is a bit tricky as it has no object code
      of its own.  To handle this we instead place the type representations
      for the types defined here in `GHC.Types`.
      
      On the whole this eliminates several special-cases as well as a fair
      amount of boilerplate from hand-written representations. Moreover, we
      get full coverage of primitive types for free.
      
      Test Plan: Validate
      
      Reviewers: goldfire, simonpj, austin, hvr
      
      Subscribers: goldfire, simonpj, thomie
      
      Differential Revision: https://phabricator.haskell.org/D1774
      
      GHC Trac Issues: #11120
      84b0ebed
  26. 11 Dec, 2015 1 commit
    • eir@cis.upenn.edu's avatar
      Add kind equalities to GHC. · 67465497
      eir@cis.upenn.edu authored
      This implements the ideas originally put forward in
      "System FC with Explicit Kind Equality" (ICFP'13).
      
      There are several noteworthy changes with this patch:
       * We now have casts in types. These change the kind
         of a type. See new constructor `CastTy`.
      
       * All types and all constructors can be promoted.
         This includes GADT constructors. GADT pattern matches
         take place in type family equations. In Core,
         types can now be applied to coercions via the
         `CoercionTy` constructor.
      
       * Coercions can now be heterogeneous, relating types
         of different kinds. A coercion proving `t1 :: k1 ~ t2 :: k2`
         proves both that `t1` and `t2` are the same and also that
         `k1` and `k2` are the same.
      
       * The `Coercion` type has been significantly enhanced.
         The documentation in `docs/core-spec/core-spec.pdf` reflects
         the new reality.
      
       * The type of `*` is now `*`. No more `BOX`.
      
       * Users can write explicit kind variables in their code,
         anywhere they can write type variables. For backward compatibility,
         automatic inference of kind-variable binding is still permitted.
      
       * The new extension `TypeInType` turns on the new user-facing
         features.
      
       * Type families and synonyms are now promoted to kinds. This causes
         trouble with parsing `*`, leading to the somewhat awkward new
         `HsAppsTy` constructor for `HsType`. This is dispatched with in
         the renamer, where the kind `*` can be told apart from a
         type-level multiplication operator. Without `-XTypeInType` the
         old behavior persists. With `-XTypeInType`, you need to import
         `Data.Kind` to get `*`, also known as `Type`.
      
       * The kind-checking algorithms in TcHsType have been significantly
         rewritten to allow for enhanced kinds.
      
       * The new features are still quite experimental and may be in flux.
      
       * TODO: Several open tickets: #11195, #11196, #11197, #11198, #11203.
      
       * TODO: Update user manual.
      
      Tickets addressed: #9017, #9173, #7961, #10524, #8566, #11142.
      Updates Haddock submodule.
      67465497
  27. 30 Oct, 2015 1 commit
    • Ben Gamari's avatar
      Generate Typeable info at definition sites · 91c6b1f5
      Ben Gamari authored
      This is the second attempt at merging D757.
      
      This patch implements the idea floated in Trac #9858, namely that we
      should generate type-representation information at the data type
      declaration site, rather than when solving a Typeable constraint.
      
      However, this turned out quite a bit harder than I expected. I still
      think it's the right thing to do, and it's done now, but it was quite
      a struggle.
      
      See particularly
      
       * Note [Grand plan for Typeable] in TcTypeable (which is a new module)
       * Note [The overall promotion story] in DataCon (clarifies existing
      stuff)
      
      The most painful bit was that to generate Typeable instances (ie
      TyConRepName bindings) for every TyCon is tricky for types in ghc-prim
      etc:
      
       * We need to have enough data types around to *define* a TyCon
       * Many of these types are wired-in
      
      Also, to minimise the code generated for each data type, I wanted to
      generate pure data, not CAFs with unpackCString# stuff floating about.
      
      Performance
      ~~~~~~~~~~~
      Three perf/compiler tests start to allocate quite a bit more. This isn't
      surprising, because they all allocate zillions of data types, with
      practically no other code, esp. T1969
      
       * T1969:    GHC allocates 19% more
       * T4801:    GHC allocates 13% more
       * T5321FD:  GHC allocates 13% more
       * T9675:    GHC allocates 11% more
       * T783:     GHC allocates 11% more
       * T5642:    GHC allocates 10% more
      
      I'm treating this as acceptable. The payoff comes in Typeable-heavy
      code.
      
      Remaining to do
      ~~~~~~~~~~~~~~~
      
       * I think that "TyCon" and "Module" are over-generic names to use for
         the runtime type representations used in GHC.Typeable. Better might
      be
         "TrTyCon" and "TrModule". But I have not yet done this
      
       * Add more info the the "TyCon" e.g. source location where it was
         defined
      
       * Use the new "Module" type to help with Trac Trac #10068
      
       * It would be possible to generate TyConRepName (ie Typeable
         instances) selectively rather than all the time. We'd need to persist
         the information in interface files. Lacking a motivating reason I
      have
         not done this, but it would not be difficult.
      
      Refactoring
      ~~~~~~~~~~~
      As is so often the case, I ended up refactoring more than I intended.
      In particular
      
       * In TyCon, a type *family* (whether type or data) is repesented by a
         FamilyTyCon
           * a algebraic data type (including data/newtype instances) is
             represented by AlgTyCon This wasn't true before; a data family
             was represented as an AlgTyCon. There are some corresponding
             changes in IfaceSyn.
      
           * Also get rid of the (unhelpfully named) tyConParent.
      
       * In TyCon define 'Promoted', isomorphic to Maybe, used when things are
         optionally promoted; and use it elsewhere in GHC.
      
       * Cleanup handling of knownKeyNames
      
       * Each TyCon, including promoted TyCons, contains its TyConRepName, if
         it has one. This is, in effect, the name of its Typeable instance.
      
      Updates haddock submodule
      
      Test Plan: Let Harbormaster validate
      
      Reviewers: austin, hvr, goldfire
      
      Subscribers: goldfire, thomie
      
      Differential Revision: https://phabricator.haskell.org/D1404
      
      GHC Trac Issues: #9858
      91c6b1f5
  28. 29 Oct, 2015 2 commits
    • Ben Gamari's avatar
      Revert "Generate Typeable info at definition sites" · bbaf76f9
      Ben Gamari authored
      This reverts commit bef2f03e.
      
      This merge was botched
      
      Also reverts haddock submodule.
      bbaf76f9
    • Ben Gamari's avatar
      Generate Typeable info at definition sites · bef2f03e
      Ben Gamari authored
      This patch implements the idea floated in Trac #9858, namely that we
      should generate type-representation information at the data type
      declaration site, rather than when solving a Typeable constraint.
      
      However, this turned out quite a bit harder than I expected. I still
      think it's the right thing to do, and it's done now, but it was quite
      a struggle.
      
      See particularly
      
       * Note [Grand plan for Typeable] in TcTypeable (which is a new module)
       * Note [The overall promotion story] in DataCon (clarifies existing stuff)
      
      The most painful bit was that to generate Typeable instances (ie
      TyConRepName bindings) for every TyCon is tricky for types in ghc-prim
      etc:
      
       * We need to have enough data types around to *define* a TyCon
       * Many of these types are wired-in
      
      Also, to minimise the code generated for each data type, I wanted to
      generate pure data, not CAFs with unpackCString# stuff floating about.
      
      Performance
      ~~~~~~~~~~~
      Three perf/compiler tests start to allocate quite a bit more. This isn't
      surprising, because they all allocate zillions of data types, with
      practically no other code, esp. T1969
      
       * T3294:   GHC allocates 110% more (filed #11030 to track this)
       * T1969:   GHC allocates 30% more
       * T4801:   GHC allocates 14% more
       * T5321FD: GHC allocates 13% more
       * T783:    GHC allocates 12% more
       * T9675:   GHC allocates 12% more
       * T5642:   GHC allocates 10% more
       * T9961:   GHC allocates 6% more
      
       * T9203:   Program allocates 54% less
      
      I'm treating this as acceptable. The payoff comes in Typeable-heavy
      code.
      
      Remaining to do
      ~~~~~~~~~~~~~~~
      
       * I think that "TyCon" and "Module" are over-generic names to use for
         the runtime type representations used in GHC.Typeable. Better might be
         "TrTyCon" and "TrModule". But I have not yet done this
      
       * Add more info the the "TyCon" e.g. source location where it was
         defined
      
       * Use the new "Module" type to help with Trac Trac #10068
      
       * It would be possible to generate TyConRepName (ie Typeable
         instances) selectively rather than all the time. We'd need to persist
         the information in interface files. Lacking a motivating reason I have
         not done this, but it would not be difficult.
      
      Refactoring
      ~~~~~~~~~~~
      As is so often the case, I ended up refactoring more than I intended.
      In particular
      
       * In TyCon, a type *family* (whether type or data) is repesented by a
         FamilyTyCon
           * a algebraic data type (including data/newtype instances) is
             represented by AlgTyCon This wasn't true before; a data family
             was represented as an AlgTyCon. There are some corresponding
             changes in IfaceSyn.
      
           * Also get rid of the (unhelpfully named) tyConParent.
      
       * In TyCon define 'Promoted', isomorphic to Maybe, used when things are
         optionally promoted; and use it elsewhere in GHC.
      
       * Cleanup handling of knownKeyNames
      
       * Each TyCon, including promoted TyCons, contains its TyConRepName, if
         it has one. This is, in effect, the name of its Typeable instance.
      
      Requires update of the haddock submodule.
      
      Differential Revision: https://phabricator.haskell.org/D757
      bef2f03e
  29. 27 Oct, 2015 1 commit
    • niteria's avatar
      Sort field labels before fingerprint hashing · ffcdd84f
      niteria authored
      `fsEnvElts :: FastStringEnv a -> [a]` returns a list of `[a]` in the order of
      `Unique`s which is arbitrary. In this case it gives a list of record fields in
      arbitrary order, from which we then extract the field labels to contribute to
      the record fingerprint. The arbitrary ordering of field labels introduces
      unnecessary nondeterminism in interface files as demonstrated by the test case.
      
      We sort `FastString` here. It's safe, because the only way that the `Unique`
      associated with the `FastString` is used in comparison is for equality. If the
      `Unique`s are different it fallbacks to comparing the actual `ByteString`.
      
      Reviewed By: ezyang, thomie, bgamari, austin
      
      Differential Revision: https://phabricator.haskell.org/D1373
      
      GHC Trac Issues: #4012
      ffcdd84f
  30. 21 Aug, 2015 1 commit
    • thomie's avatar
      Refactor: delete most of the module FastTypes · 2f29ebbb
      thomie authored
      This reverses some of the work done in #1405, and goes back to the
      assumption that the bootstrap compiler understands GHC-haskell.
      
      In particular:
        * use MagicHash instead of _ILIT and _CLIT
        * pattern matching on I# if possible, instead of using iUnbox
          unnecessarily
        * use Int#/Char#/Addr# instead of the following type synonyms:
          - type FastInt   = Int#
          - type FastChar  = Char#
          - type FastPtr a = Addr#
        * inline the following functions:
          - iBox           = I#
          - cBox           = C#
          - fastChr        = chr#
          - fastOrd        = ord#
          - eqFastChar     = eqChar#
          - shiftLFastInt  = uncheckedIShiftL#
          - shiftR_FastInt = uncheckedIShiftRL#
          - shiftRLFastInt = uncheckedIShiftRL#
        * delete the following unused functions:
          - minFastInt
          - maxFastInt
          - uncheckedIShiftRA#
          - castFastPtr
          - panicDocFastInt and pprPanicFastInt
        * rename panicFastInt back to panic#
      
      These functions remain, since they actually do something:
        * iUnbox
        * bitAndFastInt
        * bitOrFastInt
      
      Test Plan: validate
      
      Reviewers: austin, bgamari
      
      Subscribers: rwbarton
      
      Differential Revision: https://phabricator.haskell.org/D1141
      
      GHC Trac Issues: #1405
      2f29ebbb
  31. 18 May, 2015 1 commit
    • Simon Peyton Jones's avatar
      Refactor tuple constraints · ffc21506
      Simon Peyton Jones authored
      Make tuple constraints be handled by a perfectly ordinary
      type class, with the component constraints being the
      superclasses:
          class (c1, c2) => (c2, c2)
      
      This change was provoked by
      
        #10359  inability to re-use a given tuple
                constraint as a whole
      
        #9858   confusion between term tuples
                and constraint tuples
      
      but it's generally a very nice simplification. We get rid of
       -  In Type, the TuplePred constructor of PredTree,
          and all the code that dealt with TuplePreds
       -  In TcEvidence, the constructors EvTupleMk, EvTupleSel
      
      See Note [How tuples work] in TysWiredIn.
      
      Of course, nothing is ever entirely simple. This one
      proved quite fiddly.
      
      - I did quite a bit of renaming, which makes this patch
        touch a lot of modules. In partiuclar tupleCon -> tupleDataCon.
      
      - I made constraint tuples known-key rather than wired-in.
        This is different to boxed/unboxed tuples, but it proved
        awkward to have all the superclass selectors wired-in.
        Easier just to use the standard mechanims.
      
      - While I was fiddling with known-key names, I split the TH Name
        definitions out of DsMeta into a new module THNames.  That meant
        that the known-key names can all be gathered in PrelInfo, without
        causing module loops.
      
      - I found that the parser was parsing an import item like
            T( .. )
        as a *data constructor* T, and then using setRdrNameSpace to
        fix it.  Stupid!  So I changed the parser to parse a *type
        constructor* T, which means less use of setRdrNameSpace.
      
        I also improved setRdrNameSpace to behave better on Exact Names.
        Largely on priciple; I don't think it matters a lot.
      
      - When compiling a data type declaration for a wired-in thing like
        tuples (,), or lists, we don't really need to look at the
        declaration.  We have the wired-in thing!  And not doing so avoids
        having to line up the uniques for data constructor workers etc.
        See Note [Declarations for wired-in things]
      
      - I found that FunDeps.oclose wasn't taking superclasses into
        account; easily fixed.
      
      - Some error message refactoring for invalid constraints in TcValidity
      
      - Haddock needs to absorb the change too; so there is a submodule update
      ffc21506
  32. 14 May, 2015 1 commit
    • Austin Seipp's avatar
      Revert multiple commits · 3cf8ecdc
      Austin Seipp authored
      This reverts multiple commits from Simon:
      
        - 04a484ea Test Trac #10359
        - a9ccd37a Test Trac #10403
        - c0aae6f6 Test Trac #10248
        - eb6ca851 Make the "matchable-given" check happen first
        - ca173aa3 Add a case to checkValidTyCon
        - 51cbad15 Update haddock submodule
        - 6e1174da Separate transCloVarSet from fixVarSet
        - a8493e03 Fix imports in HscMain (stage2)
        - a154944b Two wibbles to fix the build
        - 5910a1bc Change in capitalisation of error msg
        - 130e93aa Refactor tuple constraints
        - 8da785d5 Delete commented-out line
      
      These break the build by causing Haddock to fail mysteriously when
      trying to examine GHC.Prim it seems.
      3cf8ecdc
  33. 13 May, 2015 1 commit
    • Simon Peyton Jones's avatar
      Refactor tuple constraints · 130e93aa
      Simon Peyton Jones authored
      Make tuple constraints be handled by a perfectly ordinary
      type class, with the component constraints being the
      superclasses:
          class (c1, c2) => (c2, c2)
      
      This change was provoked by
      
        #10359  inability to re-use a given tuple
                constraint as a whole
      
        #9858   confusion between term tuples
                and constraint tuples
      
      but it's generally a very nice simplification. We get rid of
       -  In Type, the TuplePred constructor of PredTree,
          and all the code that dealt with TuplePreds
       -  In TcEvidence, the constructors EvTupleMk, EvTupleSel
      
      See Note [How tuples work] in TysWiredIn.
      
      Of course, nothing is ever entirely simple. This one
      proved quite fiddly.
      
      - I did quite a bit of renaming, which makes this patch
        touch a lot of modules. In partiuclar tupleCon -> tupleDataCon.
      
      - I made constraint tuples known-key rather than wired-in.
        This is different to boxed/unboxed tuples, but it proved
        awkward to have all the superclass selectors wired-in.
        Easier just to use the standard mechanims.
      
      - While I was fiddling with known-key names, I split the TH Name
        definitions out of DsMeta into a new module THNames.  That meant
        that the known-key names can all be gathered in PrelInfo, without
        causing module loops.
      
      - I found that the parser was parsing an import item like
            T( .. )
        as a *data constructor* T, and then using setRdrNameSpace to
        fix it.  Stupid!  So I changed the parser to parse a *type
        constructor* T, which means less use of setRdrNameSpace.
      
        I also improved setRdrNameSpace to behave better on Exact Names.
        Largely on priciple; I don't think it matters a lot.
      
      - When compiling a data type declaration for a wired-in thing like
        tuples (,), or lists, we don't really need to look at the
        declaration.  We have the wired-in thing!  And not doing so avoids
        having to line up the uniques for data constructor workers etc.
        See Note [Declarations for wired-in things]
      
      - I found that FunDeps.oclose wasn't taking superclasses into
        account; easily fixed.
      
      - Some error message refactoring for invalid constraints in TcValidity
      130e93aa
  34. 03 Dec, 2014 1 commit
  35. 23 Sep, 2014 1 commit
  36. 15 May, 2014 1 commit
    • Herbert Valerio Riedel's avatar
      Add LANGUAGE pragmas to compiler/ source files · 23892440
      Herbert Valerio Riedel authored
      In some cases, the layout of the LANGUAGE/OPTIONS_GHC lines has been
      reorganized, while following the convention, to
      
      - place `{-# LANGUAGE #-}` pragmas at the top of the source file, before
        any `{-# OPTIONS_GHC #-}`-lines.
      
      - Moreover, if the list of language extensions fit into a single
        `{-# LANGUAGE ... -#}`-line (shorter than 80 characters), keep it on one
        line. Otherwise split into `{-# LANGUAGE ... -#}`-lines for each
        individual language extension. In both cases, try to keep the
        enumeration alphabetically ordered.
        (The latter layout is preferable as it's more diff-friendly)
      
      While at it, this also replaces obsolete `{-# OPTIONS ... #-}` pragma
      occurences by `{-# OPTIONS_GHC ... #-}` pragmas.
      23892440
  37. 14 Jul, 2012 1 commit