[Git][ghc/ghc][wip/forall-vis-coercions] 23 commits: testsuite: fix predicate on rdynamic test

Matthew Craven (@clyring) gitlab at gitlab.haskell.org
Tue May 23 21:43:00 UTC 2023 


Matthew Craven pushed to branch wip/forall-vis-coercions at Glasgow Haskell Compiler / GHC


Commits:
c6fb6690 by Peter Trommler at 2023-05-20T03:16:08-04:00
testsuite: fix predicate on rdynamic test

Test rdynamic requires dynamic linking support, which is
orthogonal to RTS linker support. Change the predicate accordingly.

Fixes #23316

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735d504e by Matthew Pickering at 2023-05-20T03:16:44-04:00
docs: Use ghc-ticket directive where appropiate in users guide

Using the directive automatically formats and links the ticket
appropiately.

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b56d7379 by Sylvain Henry at 2023-05-22T14:21:22-04:00
NCG: remove useless .align directive (#20758)

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15b93d2f by Simon Peyton Jones at 2023-05-22T14:21:58-04:00
Add test for #23156

This program had exponential typechecking time in GHC 9.4 and 9.6

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2b53f206 by Greg Steuck at 2023-05-22T20:23:11-04:00
Revert "Change hostSupportsRPaths to report False on OpenBSD"

This reverts commit 1e0d8fdb55a38ece34fa6cf214e1d2d46f5f5bf2.

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882e43b7 by Greg Steuck at 2023-05-22T20:23:11-04:00
Disable T17414 on OpenBSD

Like on other systems it's not guaranteed that there's sufficient
space in /tmp to write 2G out.

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9d531f9a by Greg Steuck at 2023-05-22T20:23:11-04:00
Bring back getExecutablePath to getBaseDir on OpenBSD

Fix #18173

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9db0eadd by Krzysztof Gogolewski at 2023-05-22T20:23:47-04:00
Add an error origin for impedance matching (#23427)

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33cf4659 by Ben Gamari at 2023-05-23T03:46:20-04:00
testsuite: Add tests for #23146

Both lifted and unlifted variants.

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76727617 by Ben Gamari at 2023-05-23T03:46:21-04:00
codeGen: Fix some Haddocks

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33a8c348 by Ben Gamari at 2023-05-23T03:46:21-04:00
codeGen: Give proper LFInfo to datacon wrappers

As noted in `Note [Conveying CAF-info and LFInfo between modules]`,
when importing a binding from another module we must ensure that it gets
the appropriate `LambdaFormInfo` if it is in WHNF to ensure that
references to it are tagged correctly.

However, the implementation responsible for doing this,
`GHC.StgToCmm.Closure.mkLFImported`, only dealt with datacon workers and
not wrappers. This lead to the crash of this program in #23146:

    module B where

    type NP :: [UnliftedType] -> UnliftedType
    data NP xs where
      UNil :: NP '[]

    module A where
    import B

    fieldsSam :: NP xs -> NP xs -> Bool
    fieldsSam UNil UNil = True

    x = fieldsSam UNil UNil

Due to its GADT nature, `UNil` produces a trivial wrapper

    $WUNil :: NP '[]
    $WUNil = UNil @'[] @~(<co:1>)

which is referenced in the RHS of `A.x`. Due to the above-mentioned bug
in `mkLFImported`, the references to `$WUNil` passed to `fieldsSam` were
not tagged. This is problematic as `fieldsSam` expected its arguments to
be tagged as they are unlifted.

The fix is straightforward: extend the logic in `mkLFImported` to cover
(nullary) datacon wrappers as well as workers. This is safe because we
know that the wrapper of a nullary datacon will be in WHNF, even if it
includes equalities evidence (since such equalities are not runtime
relevant).

Thanks to @MangoIV for the great ticket and @alt-romes for his
minimization and help debugging.

Fixes #23146.

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2fc18e9e by Rodrigo Mesquita at 2023-05-23T03:46:21-04:00
codeGen: Fix LFInfo of imported datacon wrappers

As noted in #23231 and in the previous commit, we were failing to give a
an LFInfo of LFCon to a nullary datacon wrapper from another module,
failing to properly tag pointers which ultimately led to the
segmentation fault in #23146.

On top of the previous commit which now considers wrappers where we
previously only considered workers, we change the order of the guards so
that we check for the arity of the binding before we check whether it is
a constructor. This allows us to
(1) Correctly assign `LFReEntrant` to imported wrappers whose worker was
nullary, which we previously would fail to do
(2) Remove the `isNullaryRepDataCon` predicate:
    (a) which was previously wrong, since it considered wrappers whose
    workers had zero-width arguments to be non-nullary and would fail to
    give `LFCon` to them
    (b) is now unnecessary, since arity == 0 guarantees
        - that the worker takes no arguments at all
        - and the wrapper takes no arguments and its RHS must be an
          application of the worker to zero-width-args only.
        - we lint these two items with an assertion that the datacon
          `hasNoNonZeroWidthArgs`

We also update `isTagged` to use the new logic in determining the
LFInfos of imported Ids.

The creation of LFInfos for imported Ids and this detail are explained
in Note [The LFInfo of Imported Ids].

Note that before the patch to those issues we would already consider these
nullary wrappers to have `LFCon` lambda form info; but failed to re-construct
that information in `mkLFImported`

Closes #23231, #23146

(I've additionally batched some fixes to documentation I found while
investigating this issue)

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0598f7f0 by Rodrigo Mesquita at 2023-05-23T03:46:21-04:00
Make LFInfos for DataCons on construction

As a result of the discussion in !10165, we decided to amend the
previous commit which fixed the logic of `mkLFImported` with regard to
datacon workers and wrappers.

Instead of having the logic for the LFInfo of datacons be in
`mkLFImported`, we now construct an LFInfo for all data constructors on
GHC.Types.Id.Make and store it in the `lfInfo` field.

See the new Note [LFInfo of DataCon workers and wrappers] and
ammendments to Note [The LFInfo of Imported Ids]

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12294b22 by Rodrigo Mesquita at 2023-05-23T03:46:21-04:00
Update Note [Core letrec invariant]

Authored by @simonpj

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e93ab972 by Rodrigo Mesquita at 2023-05-23T03:46:21-04:00
Rename mkLFImported to importedIdLFInfo

The `mkLFImported` sounded too much like a constructor of sorts, when
really it got the `LFInfo` of an imported Id from its `lf_info` field
when this existed, and otherwise returned a conservative estimate of
that imported Id's LFInfo. This in contrast to functions such as
`mkLFReEntrant` which really are about constructing an `LFInfo`.

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e54d9259 by Rodrigo Mesquita at 2023-05-23T03:46:21-04:00
Enforce invariant on typePrimRepArgs in the types

As part of the documentation effort in !10165 I came across this
invariant on 'typePrimRepArgs' which is easily expressed at the
type-level through a NonEmpty list.

It allowed us to remove one panic.

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b8fe6a0c by Rodrigo Mesquita at 2023-05-23T03:46:21-04:00
Merge outdated Note [Data con representation] into Note [Data constructor representation]

Introduce new Note [Constructor applications in STG] to better support
the merge, and reference it from the relevant bits in the STG syntax.

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e1590ddc by Simon Peyton Jones at 2023-05-23T03:46:57-04:00
Add the SolverStage monad

This refactoring makes a substantial improvement in the
structure of the type-checker's constraint solver: #23070.

Specifically:

* Introduced the SolverStage monad.   See GHC.Tc.Solver.Monad
  Note [The SolverStage monad]

* Make each solver pipeline (equalities, dictionaries, irreds etc)
  deal with updating the inert set, as a separate SolverStage.  There
  is sometimes special stuff to do, and it means that each full
  pipeline can have type SolverStage Void, indicating that they never
  return anything.

* Made GHC.Tc.Solver.Equality.zonkEqTypes into a SolverStage.  Much nicer.

* Combined the remnants of GHC.Tc.Solver.Canonical and
  GHC.Tc.Solver.Interact into a new module GHC.Tc.Solver.Solve.
  (Interact and Canonical are removed.)

* Gave the same treatment to dictionary and irred constraints
  as I have already done for equality constraints:
    * New types (akin to EqCt): IrredCt and DictCt
    * Ct is now just a simple sum type
          data Ct
            = CDictCan      DictCt
            | CIrredCan     IrredCt
            | CEqCan        EqCt
            | CQuantCan     QCInst
            | CNonCanonical CtEvidence
    * inert_dicts can now have the better type DictMap DictCt, instead of
      DictMap Ct; and similarly inert_irreds.

* Significantly simplified the treatment of implicit parameters.
  Previously we had a number of special cases
    * interactGivenIP, an entire function
    * special case in maybeKickOut
    * special case in findDict, when looking up dictionaries
  But actually it's simpler than that. When adding a new Given, implicit
  parameter constraint to the InertSet, we just need to kick out any
  existing inert constraints that mention that implicit parameter.

  The main work is done in GHC.Tc.Solver.InertSet.delIPDict, along with
  its auxiliary GHC.Core.Predicate.mentionsIP.

  See Note [Shadowing of implicit parameters] in GHC.Tc.Solver.Dict.

* Add a new fast-path in GHC.Tc.Errors.Hole.tcCheckHoleFit.
  See Note [Fast path for tcCheckHoleFit].  This is a big win in some cases:
  test hard_hole_fits gets nearly 40% faster (at compile time).

* Add a new fast-path for solving /boxed/ equality constraints
  (t1 ~ t2).  See Note [Solving equality classes] in GHC.Tc.Solver.Dict.
  This makes a big difference too: test T17836 compiles 40% faster.

* Implement the PermissivePlan of #23413, which concerns what happens with
  insoluble Givens.   Our previous treatment was wildly inconsistent as that
  ticket pointed out.

  A part of this, I simplified GHC.Tc.Validity.checkAmbiguity: now we simply
  don't run the ambiguity check at all if -XAllowAmbiguousTypes is on.

Smaller points:

* In `GHC.Tc.Errors.misMatchOrCND` instead of having a special case for
  insoluble /occurs/ checks, broaden in to all insouluble constraints.
  Just generally better. See Note [Insoluble mis-match] in that module.

As noted above, compile time perf gets better.  Here are the changes
over 0.5% on Fedora.  (The figures are slightly larger on Windows for
some reason.)

Metrics: compile_time/bytes allocated
-------------------------------------
                LargeRecord(normal)   -0.9%
MultiLayerModulesTH_OneShot(normal)   +0.5%
                     T11822(normal)   -0.6%
                     T12227(normal)   -1.8% GOOD
                     T12545(normal)   -0.5%
                     T13035(normal)   -0.6%
                     T15703(normal)   -1.4% GOOD
                     T16875(normal)   -0.5%
                     T17836(normal)  -40.7% GOOD
                    T17836b(normal)  -12.3% GOOD
                    T17977b(normal)   -0.5%
                      T5837(normal)   -1.1%
                      T8095(normal)   -2.7% GOOD
                      T9020(optasm)   -1.1%
             hard_hole_fits(normal)  -37.0% GOOD

                          geo. mean   -1.3%
                          minimum    -40.7%
                          maximum     +0.5%

Metric Decrease:
    T12227
    T15703
    T17836
    T17836b
    T8095
    hard_hole_fits
    LargeRecord
    T9198
    T13035

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6abf3648 by Simon Peyton Jones at 2023-05-23T03:46:57-04:00
Avoid an assertion failure in abstractFloats

The function GHC.Core.Opt.Simplify.Utils.abstractFloats
was carelessly calling lookupIdSubst_maybe on a CoVar;
but a precondition of the latter is being given an Id.

In fact it's harmless to call it on a CoVar, but still, the
precondition on lookupIdSubst_maybe makes sense, so I added
a test for CoVars.

This avoids a crash in a DEBUG compiler, but otherwise has
no effect. Fixes #23426.

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903b1cf6 by Matthew Craven at 2023-05-23T17:27:41-04:00
WIP: Track visibility in forall-coercions

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3d2428b9 by Matthew Craven at 2023-05-23T17:27:43-04:00
revert temporary renamings of the forallco constructors

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7a0f67e5 by Matthew Craven at 2023-05-23T17:27:44-04:00
make necessary testsuite changes

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01955e40 by Matthew Craven at 2023-05-23T17:27:44-04:00
accept new output for T23398

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30 changed files:

- compiler/GHC/Builtin/Types/Prim.hs
- compiler/GHC/Cmm/CLabel.hs
- compiler/GHC/CmmToAsm/AArch64/Ppr.hs
- compiler/GHC/CmmToAsm/X86/Ppr.hs
- compiler/GHC/Core.hs
- compiler/GHC/Core/Coercion.hs
- compiler/GHC/Core/Coercion.hs-boot
- compiler/GHC/Core/Coercion/Opt.hs
- compiler/GHC/Core/DataCon.hs
- compiler/GHC/Core/FVs.hs
- compiler/GHC/Core/FamInstEnv.hs
- compiler/GHC/Core/InstEnv.hs
- compiler/GHC/Core/Lint.hs
- compiler/GHC/Core/Opt/Arity.hs
- compiler/GHC/Core/Opt/Simplify/Utils.hs
- compiler/GHC/Core/Predicate.hs
- compiler/GHC/Core/Reduction.hs
- compiler/GHC/Core/Tidy.hs
- compiler/GHC/Core/TyCo/Compare.hs
- compiler/GHC/Core/TyCo/FVs.hs
- compiler/GHC/Core/TyCo/Rep.hs
- compiler/GHC/Core/TyCo/Subst.hs
- compiler/GHC/Core/TyCo/Tidy.hs
- compiler/GHC/Core/TyCon.hs
- compiler/GHC/Core/Type.hs
- compiler/GHC/Core/Unify.hs
- compiler/GHC/Core/Utils.hs
- compiler/GHC/CoreToIface.hs
- compiler/GHC/HsToCore/Binds.hs
- compiler/GHC/Iface/Rename.hs


The diff was not included because it is too large.


View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/cd59cd32042db4c5bdbc0504e1b27a52651a800c...01955e401b4b701c9ca23fb3e7b798f56d68d5a7

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