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700a1dd1
by Simon Jakobi at 2026-07-23T11:21:20-04:00
ci: Reduce lint job setup costs
Avoid fetching unnecessary history and submodules for lightweight lint
jobs. Run changelog validation without Hadrian.
Because the lint-author job is now based on the .lint template directly,
we enhance it to allow Git to read from the runner-owned checkouts,
In the previously used .lint-params template, this permissions issue was
addressed via `chown`.
Closes #27521.
Assisted-by: gpt-5.6-sol via Codex CLI
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26a44fb0
by ARATA Mizuki at 2026-07-23T11:22:10-04:00
testsuite: Fix memory issues of doublex2_* and simd010
doublex2_* had reads from uninitialized memory.
simd010 had out-of-bounds array access.
Fixes #27544
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4d798b17
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Eliminate STM_AWOKEN
It was used as nullary closure for the block_info.closure in the case of
a thread being awoken after an STM transaction.
However, while it was written, it was never read, so contributed nothing
to the behaviour. Furthermore, in the only place it was set (in
tryWakeupThread) the why_blocked was immediately overwritten by the
NotBlocked status, and the block_info was updated accordingly (by
appendToRunQueue).
So it didn't even serve a purpose of clarifying an intermediate state,
there really was no such intermediate state.
Cleaning this up will allow the BlockedOnSTM case to follow the same
pattern as the other why_blocked cases that do not use the block_info,
and in turn this reduces the number of different categories.
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e1cece79
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Document that eventlog thread stop code ThreadBlocked is no longer used
It has not been used since GHC 7.0.x (2011). In 7.2 all the BlockedOn*
codes were added, and these were and are used instead of ThreadBlocked.
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795db115
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Add a proper mapping to eventlog external thread stop status
That is the mapping from rts-internal codes, to the coes used in the
status field in the eventlog EVENT_STOP_THREAD event.
See issue #9003 for what goes wrong when we mess this up. In that
ticket, people note that we should really not require the internal
tso->why_blocked codes to leak into the external eventlog thread stop
codes. The same principle applies to the StgThreadReturnCode.
This change properly separates them, and explicitly maps between them
using a pair of (compact, constant) tables. These tables are pretty
small (with no alignment constraints) and will soon shrink so it seems
a sensible tradeoff.
We also introduce and use proper EVENT_STOP_THREAD constants in the
event log format header. Previously there was not specification in the
code for these (only in the docs): the values were encoded into the
conversion code.
This will allow us to renumber the internal why_blockd codes without
breaking the eventlog output.
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6f1c8efa
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Remove unused tso->block_info.wakeup member
Presumably it was used once, but not now.
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740b88a9
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Document StgTSOBlockInfo to say what cases use what members
In principle, tso->why_blocked is the tag for the StgTSOBlockInfo union,
so we should be able to say for each union member the why_blocked cases
that use that member.
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5b92eae2
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Add a tso->block_info.mvar member and use it
in preference to the generic block_info.closure union member, with
casts.
The plan is that when we know what case we're in (via tso->why_blocked)
then we can always access the correct union member, and so we will only
need to access block_info.closure for generic cases where we don't know
or don't care.
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d931715f
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Add a tso->block_info.unused member and use it
in preference to the generic block_info.closure union member, with
casts.
The plan is that when we know what case we're in (via tso->why_blocked)
then we can always access the correct union member, and so we will only
need to access block_info.closure for generic cases where we don't know
or don't care.
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47e28ebb
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Avoid storing to tso->block_info.closure
In one case we can use a specific union member (.prev) instead. In
several cases the stores were in fact redundant because of subsequent
overwrites.
In scavengeTSO we replace setting tso->block_info.closure to a valid
closure, with an assertion that the block_info.unused is already set to
END_TSO_QUEUE which is a valid (static) closure.
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96e4749d
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Renumber the tso->why_blocked constants
We can do this now because we have separated the internal values from
the external ones used in the eventlog.
This lets us put them back into a deliberate order and consolodate some
gaps.
More importantly, it is a prepation for a slightly more sophisticated
encoding.
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8f62661c
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Define constants for the existing stg_threadStatuszh return codes
The stg_threadStatuszh reuses the internal tso->why_blocked codes but
also extends them with a couple previously magic values. This is awkward
since we need to know what those magic values are so we don't
accidentally use those values to mean something else. By pulling a
definition up to where the why_blocked codes are defined we will be able
to avoid mistakenly assining those codes some meaning (or just changing
the BlockedThreadComplete, BlockedThreadKilled code if necessary).
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42c69ae2
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Extend the tso->why_blocked encoding to indicate block_info closures
We use some bit tricks to cheaply and generically test if a
tso->why_blocked tag implies that the corresponding tso->block_info will
contain a non-trivial valid closure (i.e. not just block_info.unused set
to END_TSO_QUEUE).
In particular we arrange for most why_blocked values to naturally have a
distinguishing bit, but for the BlockedOn{Read,Write,Delay} cases, they
can come in either non-closure or closure forms. We allow an additional
bit to distinguish these cases. The non-closure forms are only from
legacy I/O managers: select and win32-legacy. So this extra bit
mechanism will be able to be retired once the legacy I/O managers are
themselves retired.
This means in a few places we need to untag the why_blocked value before
inspecting it, but in most places we do not.
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7c64632b
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Use BlockInfoForceNonClosure in the select I/O manager
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8fd7104a
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Use BlockInfoForceNonClosure in the win32-legacy I/O manager
for the BlockedOn{Read,Write} since these use the non-heap allocated
StgAsyncIOResult.
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e0da603b
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Enforce the why_blocked and block_info rules in checkTSO
We now check the cases wher IsBlockInfoClosure should hold, the cases
that are supposed to use block_info.unused == END_TSO_QUEUE, and which
cases are allowed to use BlockInfoForceNonClosure.
This partially enforces the use of why_blocked as a tag for the
block_info union. We could be stricter and check for the correct
expected info table for the closure cases.
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1dd0f381
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Use IsBlockInfoClosure to simplify several tests
In GC and generic traversal we need to know if we should look at the
block_info.closure or not. Now we can do just that using a cheap bit
test on the why_blocked tag.
This fixes issue 26717, where the problem was that some GC modes did not
know when to look at block_info.closure, because the poll I/O manager
uses a closure for BlockedOn{Read,Write} while the select I/O manager
uses a non-closure. Now this information is in the why_blocked tag
itself.
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7a00ffbc
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Remove the now-unused scavengeTSOIOManager
The GC no longer has to delegate to the I/O manager, since it can use
IsBlockInfoClosure to decide things itself.
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522a481f
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Remove duplicate assertion
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0874d965
by Duncan Coutts at 2026-07-23T17:26:18-04:00
Follow atomic access rules more consistently for tso->why_blocked
The rule is this:
store block_info *before* why_blocked
store why_blocked using store release
load why_blocked using load acquire
load block_info *after* why_blocked
This is a an atomic store release / load acquire pair and (if the reads
are in a separate thread to the writes, and the read receives the value
stored) then this guarantees a full "happens before" relationship of
these stores and loads.
In some cases, we do not need a full load acquire, because we don't read
the block_info at all and so do not need any ordering. In this case we
just need an atomic relaxed load.
This was being followed in most places, but not all. If there's good
reason in any case that we don't need atomic access, then we should
document that in a comment. In the absence of that I think it's easier
to follow the rule everywhere.
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8f0bdbe1
by Duncan Coutts at 2026-07-23T17:26:19-04:00
Add a changelog entry
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4fdfe757
by Alan Zimmerman at 2026-07-23T17:27:06-04:00
EPA: Keep decls together in ClassDecl
Similar to 1718230f4d3d19d8c49c0e5d496cb0fb6f399528 for HsValBindsLR,
this commit updates ClassDecl so that it no longer splits out the
assorted `LHsDecl GhcPs` until the renamer.
It does this by inserting a type family (separate from the classic TTG one) for this.
So
data TyClDecl
...
| ClassDecl {
...
tcdDecls :: XClassDecls pass
with
type instance XClassDecls GhcPs = [LHsDecl GhcPs]
type instance XClassDecls GhcRn = ClassDeclX GhcRn
type instance XClassDecls GhcTc = ClassDeclX GhcTc
data ClassDeclX pass
= ClassDeclX { tcdSigs :: [LSig pass], -- ^ Methods' signatures
tcdMeths :: LHsBinds pass, -- ^ Default methods
tcdATs :: [LFamilyDecl pass], -- ^ Associated types;
tcdATDefs :: [LTyFamDefltDecl pass], -- ^ Associated type defaults
tcdDocs :: [LDocDecl pass] -- ^ Haddock docs
}
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d1bebb2b
by Alan Zimmerman at 2026-07-23T23:00:05+01:00
EPA: ClsInstDecl with decls as [LHsDecl GhcPs] in GhcPs
Similar to 4fdfe75731e01dad7d7fa474c2703d0d3965afb1, this commit
changes the as-parsed representation of class instance declarations to
[LHsDecl GhcPs], and only separates them by type from the renamer onward.
This also allows us to remove all the AnnSortKey machinery for exact
printing, as it is now no longer needed.
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6eb20465
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Remove LocatedP from OverlapMode
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8e16e84b
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Remove LocatedP from CType
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7b7be728
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Remove LocatedP, last use in WarningTxt
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319892c6
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Remove LocatedE from WarningCategory
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3d11d433
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Remove LocateE from XCImport and XCExport
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7a4ba50b
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Remove LocatedE from HsRecFields dot
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28dd0632
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Remove LocatedE completely, last usage for pats
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7b0c880f
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Remove AnnList (EpToken "where") usages
This is moving toward removing the parameter from AnnList completely
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65acf336
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA remove AnnList (EpToken "rec") usages
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418dc141
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Remove last parameterised AnnList usage (EpaLocation)
Also remove the parameter
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0f715654
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
TTG: Add extension points to BooleanFormula
They are currently unused, but will be used for exact print annotations next
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37c1a8e4
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Remove LocatedBC / SrcSpanBF
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4a6c7308
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: remove unused addTrailingAnnToL. Squash appropriately
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9aa54865
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPS: Remove NoEpTok/NoEpUniTok, using an unhelpful SrcSpan instead
Also introduce helper functions noEpTok and noEpUniTok to serve
as simple replacements in code inserting an token annotation without
location information.
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15dbc626
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Some haddock processing tweaks
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7a4e20a5
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
Some haddock exactprint tests
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bfe22be7
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: When adding comments honour trailing anns
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e97a96d5
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Uses Parsers.parseModule for exactprint tests
This is the advertised way to parse for use for exact printing in the
ghc-exactprint library, make sure we test using it.
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a3e005d4
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA Fix HsCmdDo exact print with comments
TODO: add test based on proc-do-complex-four-out.hs
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9c28ea49
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
WIP on removing NoEpAnn. Likely abandon
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86eb8cb0
by Alan Zimmerman at 2026-07-23T23:00:49+01:00
EPA: Add an overview doc for exact printing
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a1549398
by Simon Peyton Jones at 2026-07-23T23:00:49+01:00
Added an intro section