[Git][ghc/ghc][wip/T17923] 25 commits: Clean up "Eta reduction for data families" Notes
Ömer Sinan Ağacan
gitlab at gitlab.haskell.org
Sun Apr 5 09:03:25 UTC 2020
Ömer Sinan Ağacan pushed to branch wip/T17923 at Glasgow Haskell Compiler / GHC
Commits:
9b39f2e6 by Ryan Scott at 2020-04-01T01:20:00-04:00
Clean up "Eta reduction for data families" Notes
Before, there were two distinct Notes named
"Eta reduction for data families". This renames one of them to
"Implementing eta reduction for data families" to disambiguate the
two and fixes references in other parts of the codebase to ensure
that they are pointing to the right place.
Fixes #17313.
[ci skip]
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7627eab5 by Ryan Scott at 2020-04-01T01:20:38-04:00
Fix the changelog/@since information for hGetContents'/getContents'/readFile'
Fixes #17979.
[ci skip]
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0002db1b by Sylvain Henry at 2020-04-01T01:21:27-04:00
Kill wORDS_BIGENDIAN and replace it with platformByteOrder (#17957)
Metric Decrease:
T13035
T1969
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7b217179 by Sebastian Graf at 2020-04-01T15:03:24-04:00
PmCheck: Adjust recursion depth for inhabitation test
In #17977, we ran into the reduction depth limit of the typechecker.
That was only a symptom of a much broader issue: The recursion depth
of the coverage checker for trying to instantiate strict fields in the
`nonVoid` test was far too high (100, the `defaultMaxTcBound`).
As a result, we were performing quite poorly on `T17977`.
Short of a proper termination analysis to prove emptyness of a type,
we just arbitrarily default to a much lower recursion limit of 3.
Fixes #17977.
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3c09f636 by Andreas Klebinger at 2020-04-01T15:03:59-04:00
Make hadrian pass on the no-colour setting to GHC.
Fixes #17983.
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b943b25d by Simon Peyton Jones at 2020-04-02T01:45:58-04:00
Re-engineer the binder-swap transformation
The binder-swap transformation is implemented by the occurrence
analyser -- see Note [Binder swap] in OccurAnal. However it had
a very nasty corner in it, for the case where the case scrutinee
was a GlobalId. This led to trouble and hacks, and ultimately
to #16296.
This patch re-engineers how the occurrence analyser implements
the binder-swap, by actually carrying out a substitution rather
than by adding a let-binding. It's all described in
Note [The binder-swap substitution].
I did a few other things along the way
* Fix a bug in StgCse, which could allow a loop breaker to be CSE'd
away. See Note [Care with loop breakers] in StgCse. I think it can
only show up if occurrence analyser sets up bad loop breakers, but
still.
* Better commenting in SimplUtils.prepareAlts
* A little refactoring in CoreUnfold; nothing significant
e.g. rename CoreUnfold.mkTopUnfolding to mkFinalUnfolding
* Renamed CoreSyn.isFragileUnfolding to hasCoreUnfolding
* Move mkRuleInfo to CoreFVs
We observed respectively 4.6% and 5.9% allocation decreases for the following
tests:
Metric Decrease:
T9961
haddock.base
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42d68364 by Sebastian Graf at 2020-04-02T01:46:34-04:00
Preserve precise exceptions in strictness analysis
Fix #13380 and #17676 by
1. Changing `raiseIO#` to have `topDiv` instead of `botDiv`
2. Give it special treatment in `Simplifier.Util.mkArgInfo`, treating it
as if it still had `botDiv`, to recover dead code elimination.
This is the first commit of the plan outlined in
https://gitlab.haskell.org/ghc/ghc/-/merge_requests/2525#note_260886.
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0a88dd11 by Ömer Sinan Ağacan at 2020-04-02T01:47:25-04:00
Fix a pointer format string in RTS
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5beac042 by Ömer Sinan Ağacan at 2020-04-02T01:48:05-04:00
Remove unused closure stg_IND_direct
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88f38b03 by Ben Gamari at 2020-04-02T01:48:42-04:00
Session: Memoize stderrSupportsAnsiColors
Not only is this a reasonable efficiency measure but it avoids making
reentrant calls into ncurses, which is not thread-safe. See #17922.
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27740f24 by Ryan Scott at 2020-04-02T01:49:21-04:00
Make Hadrian build with Cabal-3.2
GHC 8.10 ships with `Cabal-3.2.0.0`, so it would be convenient to
make Hadrian supporting building against 3.2.* instead of having to
rebuild the entirety of `Cabal-3.0.0.0`. There is one API change in
`Cabal-3.2.*` that affects Hadrian: the `synopsis` and `description`
functions now return `ShortText` instead of `String`. Since Hadrian
manipulates these `String`s in various places, I found that the
simplest fix was to use CPP to convert `ShortText` to `String`s
where appropriate.
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49802002 by Sylvain Henry at 2020-04-02T01:50:00-04:00
Update Stack resolver for hadrian/build-stack
Broken by 57b888c0e90be7189285a6b078c30b26d0923809
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30a63e79 by Ryan Scott at 2020-04-02T01:50:36-04:00
Fix two ASSERT buglets in reifyDataCon
Two `ASSERT`s in `reifyDataCon` were always using `arg_tys`, but
`arg_tys` is not meaningful for GADT constructors. In fact, it's
worse than non-meaningful, since using `arg_tys` when reifying a
GADT constructor can lead to failed `ASSERT`ions, as #17305
demonstrates.
This patch applies the simplest possible fix to the immediate
problem. The `ASSERT`s now use `r_arg_tys` instead of `arg_tys`, as
the former makes sure to give something meaningful for GADT
constructors. This makes the panic go away at the very least. There
is still an underlying issue with the way the internals of
`reifyDataCon` work, as described in
https://gitlab.haskell.org/ghc/ghc/issues/17305#note_227023, but we
leave that as future work, since fixing the underlying issue is
much trickier (see
https://gitlab.haskell.org/ghc/ghc/issues/17305#note_227087).
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ef7576c4 by Zubin Duggal at 2020-04-03T06:24:56-04:00
Add outputable instances for the types in GHC.Iface.Ext.Types, add -ddump-hie
flag to dump pretty printed contents of the .hie file
Metric Increase:
hie002
Because of the regression on i386:
compile_time/bytes allocated increased from i386-linux-deb9 baseline @ HEAD~10:
Expected hie002 (normal) compile_time/bytes allocated: 583014888.0 +/-10%
Lower bound hie002 (normal) compile_time/bytes allocated: 524713399
Upper bound hie002 (normal) compile_time/bytes allocated: 641316377
Actual hie002 (normal) compile_time/bytes allocated: 877986292
Deviation hie002 (normal) compile_time/bytes allocated: 50.6 %
*** unexpected stat test failure for hie002(normal)
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9462452a by Andreas Klebinger at 2020-04-03T06:25:33-04:00
Improve and refactor StgToCmm codegen for DataCons.
We now differentiate three cases of constructor bindings:
1)Bindings which we can "replace" with a reference to
an existing closure. Reference the replacement closure
when accessing the binding.
2)Bindings which we can "replace" as above. But we still
generate a closure which will be referenced by modules
importing this binding.
3)For any other binding generate a closure. Then reference
it.
Before this patch 1) did only apply to local bindings and we
didn't do 2) at all.
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a214d214 by Moritz Bruder at 2020-04-03T06:26:11-04:00
Add singleton to NonEmpty in libraries/base
This adds a definition to construct a singleton non-empty list
(Data.List.NonEmpty) according to issue #17851.
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f7597aa0 by Sylvain Henry at 2020-04-03T06:26:54-04:00
Testsuite: measure compiler stats for T16190
We were mistakenly measuring program stats
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a485c3c4 by Sylvain Henry at 2020-04-03T06:26:54-04:00
Move blob handling into StgToCmm
Move handling of big literal strings from CmmToAsm to StgToCmm. It
avoids the use of `sdocWithDynFlags` (cf #10143). We might need to move
this handling even higher in the pipeline in the future (cf #17960):
this patch will make it easier.
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cc2918a0 by Sylvain Henry at 2020-04-03T06:26:54-04:00
Refactor CmmStatics
In !2959 we noticed that there was some redundant code (in GHC.Cmm.Utils
and GHC.Cmm.StgToCmm.Utils) used to deal with `CmmStatics` datatype
(before SRT generation) and `RawCmmStatics` datatype (after SRT
generation).
This patch removes this redundant code by using a single GADT for
(Raw)CmmStatics.
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9e60273d by Maxim Koltsov at 2020-04-03T06:27:32-04:00
Fix haddock formatting in Control.Monad.ST.Lazy.Imp.hs
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1b7e8a94 by Andreas Klebinger at 2020-04-03T06:28:08-04:00
Turn newlines into spaces for hadrian/ghci.
The newlines break the command on windows.
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4291bdda by Simon Peyton Jones at 2020-04-03T06:28:44-04:00
Major improvements to the specialiser
This patch is joint work of Alexis King and Simon PJ. It does some
significant refactoring of the type-class specialiser. Main highlights:
* We can specialise functions with types like
f :: Eq a => a -> Ord b => b => blah
where the classes aren't all at the front (#16473). Here we can
correctly specialise 'f' based on a call like
f @Int @Bool dEqInt x dOrdBool
This change really happened in an earlier patch
commit 2d0cf6252957b8980d89481ecd0b79891da4b14b
Author: Sandy Maguire <sandy at sandymaguire.me>
Date: Thu May 16 12:12:10 2019 -0400
work that this new patch builds directly on that work, and refactors
it a bit.
* We can specialise functions with implicit parameters (#17930)
g :: (?foo :: Bool, Show a) => a -> String
Previously we could not, but now they behave just like a non-class
argument as in 'f' above.
* We can specialise under-saturated calls, where some (but not all of
the dictionary arguments are provided (#17966). For example, we can
specialise the above 'f' based on a call
map (f @Int dEqInt) xs
even though we don't (and can't) give Ord dictionary.
This may sound exotic, but #17966 is a program from the wild, and
showed significant perf loss for functions like f, if you need
saturation of all dictionaries.
* We fix a buglet in which a floated dictionary had a bogus demand
(#17810), by using zapIdDemandInfo in the NonRec case of specBind.
* A tiny side benefit: we can drop dead arguments to specialised
functions; see Note [Drop dead args from specialisations]
* Fixed a bug in deciding what dictionaries are "interesting"; see
Note [Keep the old dictionaries interesting]
This is all achieved by by building on Sandy Macguire's work in
defining SpecArg, which mkCallUDs uses to describe the arguments of
the call. Main changes:
* Main work is in specHeader, which marched down the [InBndr] from the
function definition and the [SpecArg] from the call site, together.
* specCalls no longer has an arity check; the entire mechanism now
handles unders-saturated calls fine.
* mkCallUDs decides on an argument-by-argument basis whether to
specialise a particular dictionary argument; this is new.
See mk_spec_arg in mkCallUDs.
It looks as if there are many more lines of code, but I think that
all the extra lines are comments!
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40a85563 by Ömer Sinan Ağacan at 2020-04-03T18:26:19+03:00
Revert accidental change in 9462452
[ci skip]
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bd75e5da by Ryan Scott at 2020-04-04T07:07:58-04:00
Enable ImpredicativeTypes internally when typechecking selector bindings
This is necessary for certain record selectors with higher-rank
types, such as the examples in #18005. See
`Note [Impredicative record selectors]` in `TcTyDecls`.
Fixes #18005.
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92904edf by Simon Peyton Jones at 2020-04-05T05:03:22-04:00
Significant refactor of Lint
This refactoring of Lint was triggered by #17923, which is
fixed by this patch.
The main change is this. Instead of
lintType :: Type -> LintM LintedKind
we now have
lintType :: Type -> LintM LintedType
Previously, all of typeKind was effectively duplicate in lintType.
Moreover, since we have an ambient substitution, we still had to
apply the substition here and there, sometimes more than once. It
was all very tricky, in the end, and made my head hurt.
Now, lintType returns a fully linted type, with all substitutions
performed on it. This is much simpler.
The same thing is needed for Coercions. Instead of
lintCoercion :: OutCoercion
-> LintM (LintedKind, LintedKind,
LintedType, LintedType, Role)
we now have
lintCoercion :: Coercion -> LintM LintedCoercion
Much simpler! The code is shorter and less bug-prone.
There are a lot of knock on effects. But life is now better.
Metric Decrease:
T1969
- - - - -
28 changed files:
- compiler/GHC/Cmm.hs
- compiler/GHC/Cmm/DebugBlock.hs
- compiler/GHC/Cmm/Info.hs
- compiler/GHC/Cmm/Info/Build.hs
- compiler/GHC/Cmm/Parser.y
- compiler/GHC/Cmm/Ppr/Decl.hs
- compiler/GHC/Cmm/Utils.hs
- compiler/GHC/CmmToAsm/PPC/CodeGen.hs
- compiler/GHC/CmmToAsm/PPC/Ppr.hs
- compiler/GHC/CmmToAsm/PPC/RegInfo.hs
- compiler/GHC/CmmToAsm/Ppr.hs
- compiler/GHC/CmmToAsm/SPARC/CodeGen.hs
- compiler/GHC/CmmToAsm/SPARC/CodeGen/Gen32.hs
- compiler/GHC/CmmToAsm/SPARC/Ppr.hs
- compiler/GHC/CmmToAsm/SPARC/ShortcutJump.hs
- compiler/GHC/CmmToAsm/X86/CodeGen.hs
- compiler/GHC/CmmToAsm/X86/Instr.hs
- compiler/GHC/CmmToAsm/X86/Ppr.hs
- compiler/GHC/CmmToC.hs
- compiler/GHC/CmmToLlvm.hs
- compiler/GHC/CmmToLlvm/Data.hs
- compiler/GHC/CmmToLlvm/Ppr.hs
- compiler/GHC/Core.hs
- compiler/GHC/Core/Coercion.hs
- compiler/GHC/Core/Coercion/Axiom.hs
- compiler/GHC/Core/FVs.hs
- compiler/GHC/Core/FamInstEnv.hs
- compiler/GHC/Core/Lint.hs
The diff was not included because it is too large.
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/677b7eaa88117290ccedd85e7a2e1079d378ba53...92904edf42b8bf154e3e6ab0680bb17d31d0d71b
--
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/677b7eaa88117290ccedd85e7a2e1079d378ba53...92904edf42b8bf154e3e6ab0680bb17d31d0d71b
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