[Git][ghc/ghc][wip/andreask/xchg_primop] 122 commits: DmdAnal: Improve handling of precise exceptions
Andreas Klebinger
gitlab at gitlab.haskell.org
Tue Jun 2 10:16:41 UTC 2020
Andreas Klebinger pushed to branch wip/andreask/xchg_primop at Glasgow Haskell Compiler / GHC
Commits:
9bd20e83 by Sebastian Graf at 2020-05-15T10:42:09-04:00
DmdAnal: Improve handling of precise exceptions
This patch does two things: Fix possible unsoundness in what was called
the "IO hack" and implement part 2.1 of the "fixing precise exceptions"
plan in
https://gitlab.haskell.org/ghc/ghc/wikis/fixing-precise-exceptions,
which, in combination with !2956, supersedes !3014 and !2525.
**IO hack**
The "IO hack" (which is a fallback to preserve precise exceptions
semantics and thus soundness, rather than some smart thing that
increases precision) is called `exprMayThrowPreciseException` now.
I came up with two testcases exemplifying possible unsoundness (if
twisted enough) in the old approach:
- `T13380d`: Demonstrating unsoundness of the "IO hack" when resorting
to manual state token threading and direct use of primops.
More details below.
- `T13380e`: Demonstrating unsoundness of the "IO hack" when we have
Nested CPR. Not currently relevant, as we don't have Nested
CPR yet.
- `T13380f`: Demonstrating unsoundness of the "IO hack" for safe FFI
calls.
Basically, the IO hack assumed that precise exceptions can only be
thrown from a case scrutinee of type `(# State# RealWorld, _ #)`. I
couldn't come up with a program using the `IO` abstraction that violates
this assumption. But it's easy to do so via manual state token threading
and direct use of primops, see `T13380d`. Also similar code might be
generated by Nested CPR in the (hopefully not too) distant future, see
`T13380e`. Hence, we now have a more careful test in `forcesRealWorld`
that passes `T13380{d,e}` (and will hopefully be robust to Nested CPR).
**Precise exceptions**
In #13380 and #17676 we saw that we didn't preserve precise exception
semantics in demand analysis. We fixed that with minimal changes in
!2956, but that was terribly unprincipled.
That unprincipledness resulted in a loss of precision, which is tracked
by these new test cases:
- `T13380b`: Regression in dead code elimination, because !2956 was too
syntactic about `raiseIO#`
- `T13380c`: No need to apply the "IO hack" when the IO action may not
throw a precise exception (and the existing IO hack doesn't
detect that)
Fixing both issues in !3014 turned out to be too complicated and had
the potential to regress in the future. Hence we decided to only fix
`T13380b` and augment the `Divergence` lattice with a new middle-layer
element, `ExnOrDiv`, which means either `Diverges` (, throws an
imprecise exception) or throws a *precise* exception.
See the wiki page on Step 2.1 for more implementational details:
https://gitlab.haskell.org/ghc/ghc/wikis/fixing-precise-exceptions#dead-code-elimination-for-raiseio-with-isdeadenddiv-introducing-exnordiv-step-21
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568d7279 by Ben Gamari at 2020-05-15T10:42:46-04:00
GHC.Cmm.Opt: Handle MO_XX_Conv
This MachOp was introduced by 2c959a1894311e59cd2fd469c1967491c1e488f3
but a wildcard match in cmmMachOpFoldM hid the fact that it wasn't
handled. Ideally we would eliminate the match but this appears to be a
larger task.
Fixes #18141.
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5bcf8606 by Ryan Scott at 2020-05-17T08:46:38-04:00
Remove duplicate Note [When to print foralls] in GHC.Core.TyCo.Ppr
There are two different Notes named `[When to print foralls]`. The
most up-to-date one is in `GHC.Iface.Type`, but there is a second
one in `GHC.Core.TyCo.Ppr`. The latter is less up-to-date, as it was
written before GHC switched over to using ifaces to pretty-print
types. I decided to just remove the latter and replace it with a
reference to the former.
[ci skip]
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55f0e783 by Fumiaki Kinoshita at 2020-05-21T12:10:44-04:00
base: Add Generic instances to various datatypes under GHC.*
* GHC.Fingerprint.Types: Fingerprint
* GHC.RTS.Flags: GiveGCStats, GCFlags, ConcFlags, DebugFlags, CCFlags, DoHeapProfile, ProfFlags, DoTrace, TraceFlags, TickyFlags, ParFlags and RTSFlags
* GHC.Stats: RTSStats and GCStats
* GHC.ByteOrder: ByteOrder
* GHC.Unicode: GeneralCategory
* GHC.Stack.Types: SrcLoc
Metric Increase:
haddock.base
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a9311cd5 by Gert-Jan Bottu at 2020-05-21T12:11:31-04:00
Explicit Specificity
Implementation for Ticket #16393.
Explicit specificity allows users to manually create inferred type variables,
by marking them with braces.
This way, the user determines which variables can be instantiated through
visible type application.
The additional syntax is included in the parser, allowing users to write
braces in type variable binders (type signatures, data constructors etc).
This information is passed along through the renamer and verified in the
type checker.
The AST for type variable binders, data constructors, pattern synonyms,
partial signatures and Template Haskell has been updated to include the
specificity of type variables.
Minor notes:
- Bumps haddock submodule
- Disables pattern match checking in GHC.Iface.Type with GHC 8.8
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24e61aad by Ben Price at 2020-05-21T12:12:17-04:00
Lint should say when it is checking a rule
It is rather confusing that when lint finds an error in a rule attached
to a binder, it reports the error as in the RHS, not the rule:
...
In the RHS of foo
We add a clarifying line:
...
In the RHS of foo
In a rule attached to foo
The implication that the rule lives inside the RHS is a bit odd, but
this niggle is already present for unfoldings, whose pattern we are
following.
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78c6523c by Ben Gamari at 2020-05-21T12:13:01-04:00
nonmoving: Optimise the write barrier
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13f6c9d0 by Andreas Klebinger at 2020-05-21T12:13:45-04:00
Refactor linear reg alloc to remember past assignments.
When assigning registers we now first try registers we
assigned to in the past, instead of picking the "first"
one.
This is in extremely helpful when dealing with loops for
which variables are dead for part of the loop.
This is important for patterns like this:
foo = arg1
loop:
use(foo)
...
foo = getVal()
goto loop;
There we:
* assign foo to the register of arg1.
* use foo, it's dead after this use as it's overwritten after.
* do other things.
* look for a register to put foo in.
If we pick an arbitrary one it might differ from the register the
start of the loop expect's foo to be in.
To fix this we simply look for past register assignments for
the given variable. If we find one and the register is free we
use that register.
This reduces the need for fixup blocks which match the register
assignment between blocks. In the example above between the end
and the head of the loop.
This patch also moves branch weight estimation ahead of register
allocation and adds a flag to control it (cmm-static-pred).
* It means the linear allocator is more likely to assign the hotter
code paths first.
* If it assign these first we are:
+ Less likely to spill on the hot path.
+ Less likely to introduce fixup blocks on the hot path.
These two measure combined are surprisingly effective. Based on nofib
we get in the mean:
* -0.9% instructions executed
* -0.1% reads/writes
* -0.2% code size.
* -0.1% compiler allocations.
* -0.9% compile time.
* -0.8% runtime.
Most of the benefits are simply a result of removing redundant moves
and spills.
Reduced compiler allocations likely are the result of less code being
generated. (The added lookup is mostly non-allocating).
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edc2cc58 by Andreas Klebinger at 2020-05-21T12:14:25-04:00
NCG: Codelayout: Distinguish conditional and other branches.
In #18053 we ended up with a suboptimal code layout because
the code layout algorithm didn't distinguish between conditional
and unconditional control flow.
We can completely eliminate unconditional control flow instructions
by placing blocks next to each other, not so much for conditionals.
In terms of implementation we simply give conditional branches less
weight before computing the layout.
Fixes #18053
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b7a6b2f4 by Gleb Popov at 2020-05-21T12:15:26-04:00
gitlab-ci: Set locale to C.UTF-8.
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a8c27cf6 by Stefan Holdermans at 2020-05-21T12:16:08-04:00
Allow spaces in GHCi :script file names
This patch updates the user interface of GHCi so that file names passed
to the ':script' command may contain spaces escaped with a backslash.
For example:
:script foo\ bar.script
The implementation uses a modified version of 'words' that does not
break on escaped spaces.
Fixes #18027.
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82663959 by Stefan Holdermans at 2020-05-21T12:16:08-04:00
Add extra tests for GHCi :script syntax checks
The syntax for GHCi's ":script" command allows for only a single file
name to be passed as an argument. This patch adds a test for the cases
in which a file name is missing or multiple file names are passed.
Related to #T18027.
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a0b79e1b by Stefan Holdermans at 2020-05-21T12:16:08-04:00
Allow GHCi :script file names in double quotes
This patch updates the user interface of GHCi so that file names passed
to the ':script' command can be wrapped in double quotes.
For example:
:script "foo bar.script"
The implementation uses a modified version of 'words' that treats
character sequences enclosed in double quotes as single words.
Fixes #18027.
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cf566330 by Stefan Holdermans at 2020-05-21T12:16:08-04:00
Update documentation for GHCi :script
This patch adds the fixes that allow for file names containing spaces to
be passed to GHCi's ':script' command to the release notes for 8.12 and
expands the user-guide documentation for ':script' by mentioning how
such file names can be passed.
Related to #18027.
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0004ccb8 by Tuan Le at 2020-05-21T12:16:46-04:00
llvmGen: Consider Relocatable read-only data as not constantReferences: #18137
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964d3ea2 by John Ericson at 2020-05-21T12:17:30-04:00
Use `Checker` for `tc_pat`
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b797aa42 by John Ericson at 2020-05-21T12:17:30-04:00
Use `Checker` for `tc_lpat` and `tc_lpats`
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5108e84a by John Ericson at 2020-05-21T12:17:30-04:00
More judiciously panic in `ts_pat`
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510e0451 by John Ericson at 2020-05-21T12:17:30-04:00
Put `PatEnv` first in `GHC.Tc.Gen.Pat.Checker`
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cb4231db by John Ericson at 2020-05-21T12:17:30-04:00
Tiny cleaup eta-reduce away a function argument
In GHC, not in the code being compiled!
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6890c38d by John Ericson at 2020-05-21T12:17:30-04:00
Use braces with do in `SplicePat` case for consistency
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3451584f by buggymcbugfix at 2020-05-21T12:18:06-04:00
Fix spelling mistakes and typos
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b552e531 by buggymcbugfix at 2020-05-21T12:18:06-04:00
Add INLINABLE pragmas to Enum list producers
The INLINABLE pragmas ensure that we export stable (unoptimised) unfoldings in
the interface file so we can do list fusion at usage sites.
Related tickets: #15185, #8763, #18178.
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e7480063 by buggymcbugfix at 2020-05-21T12:18:06-04:00
Piggyback on Enum Word methods for Word64
If we are on a 64 bit platform, we can use the efficient Enum Word
methods for the Enum Word64 instance.
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892b0c41 by buggymcbugfix at 2020-05-21T12:18:06-04:00
Document INLINE(ABLE) pragmas that enable fusion
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2b363ebb by Richard Eisenberg at 2020-05-21T12:18:45-04:00
MR template should ask for key part
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a95bbd0b by Sebastian Graf at 2020-05-21T12:19:37-04:00
Make `Int`'s `mod` and `rem` strict in their first arguments
They used to be strict until 4d2ac2d (9 years ago).
It's obviously better to be strict for performance reasons.
It also blocks #18067.
NoFib results:
```
--------------------------------------------------------------------------------
Program Allocs Instrs
--------------------------------------------------------------------------------
integer -1.1% +0.4%
wheel-sieve2 +21.2% +20.7%
--------------------------------------------------------------------------------
Min -1.1% -0.0%
Max +21.2% +20.7%
Geometric Mean +0.2% +0.2%
```
The regression in `wheel-sieve2` is due to reboxing that likely will go
away with the resolution of #18067. See !3282 for details.
Fixes #18187.
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d3d055b8 by Galen Huntington at 2020-05-21T12:20:18-04:00
Clarify pitfalls of NegativeLiterals; see #18022.
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1b508a9e by Alexey Kuleshevich at 2020-05-21T12:21:02-04:00
Fix wording in primops documentation to reflect the correct reasoning:
* Besides resizing functions, shrinking ones also mutate the
size of a mutable array and because of those two `sizeofMutabeByteArray`
and `sizeofSmallMutableArray` are now deprecated
* Change reference in documentation to the newer functions `getSizeof*`
instead of `sizeof*` for shrinking functions
* Fix incorrect mention of "byte" instead of "small"
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4ca0c8a1 by Andreas Klebinger at 2020-05-21T12:21:53-04:00
Don't variable-length encode magic iface constant.
We changed to use variable length encodings for many types by default,
including Word32. This makes sense for numbers but not when Word32 is
meant to represent four bytes.
I added a FixedLengthEncoding newtype to Binary who's instances
interpret their argument as a collection of bytes instead of a number.
We then use this when writing/reading magic numbers to the iface file.
I also took the libery to remove the dummy iface field.
This fixes #18180.
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a1275081 by Krzysztof Gogolewski at 2020-05-21T12:22:35-04:00
Add a regression test for #11506
The testcase works now.
See explanation in https://gitlab.haskell.org/ghc/ghc/issues/11506#note_273202
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8a816e5f by Krzysztof Gogolewski at 2020-05-21T12:23:55-04:00
Sort deterministically metric output
Previously, we sorted according to the test name and way,
but the metrics (max_bytes_used/peak_megabytes_allocated etc.)
were appearing in nondeterministic order.
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566cc73f by Sylvain Henry at 2020-05-21T12:24:45-04:00
Move isDynLinkName into GHC.Types.Name
It doesn't belong into GHC.Unit.State
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d830bbc9 by Adam Sandberg Ericsson at 2020-05-23T13:36:20-04:00
docs: fix formatting and add some links
[skip ci]
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49301ad6 by Andrew Martin at 2020-05-23T13:37:01-04:00
Implement cstringLength# and FinalPtr
This function and its accompanying rule resolve issue #5218.
A future PR to the bytestring library will make the internal
Data.ByteString.Internal.unsafePackAddress compute string length
with cstringLength#. This will improve the status quo because it is
eligible for constant folding.
Additionally, introduce a new data constructor to ForeignPtrContents
named FinalPtr. This additional data constructor, when used in the
IsString instance for ByteString, leads to more Core-to-Core
optimization opportunities, fewer runtime allocations, and smaller
binaries.
Also, this commit re-exports all the functions from GHC.CString
(including cstringLength#) in GHC.Exts. It also adds a new test
driver. This test driver is used to perform substring matches on Core
that is dumped after all the simplifier passes. In this commit, it is
used to check that constant folding of cstringLength# works.
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dcd6bdcc by Ben Gamari at 2020-05-23T13:37:48-04:00
simplCore: Ignore ticks in rule templates
This fixes #17619, where a tick snuck in to the template of a rule,
resulting in a panic during rule matching. The tick in question was
introduced via post-inlining, as discussed in `Note [Simplifying
rules]`. The solution we decided upon was to simply ignore ticks in the
rule template, as discussed in `Note [Tick annotations in RULE
matching]`.
Fixes #18162.
Fixes #17619.
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82cb8913 by John Ericson at 2020-05-23T13:38:32-04:00
Fix #18145 and also avoid needless work with implicit vars
- `forAllOrNothing` now is monadic, so we can trace whether we bind
an explicit `forall` or not.
- #18145 arose because the free vars calculation was needlessly
complex. It is now greatly simplified.
- Replaced some other implicit var code with `filterFreeVarsToBind`.
Co-authored-by: Ryan Scott <ryan.gl.scott at gmail.com>
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a60dc835 by Ben Gamari at 2020-05-23T13:39:12-04:00
Bump process submodule
Fixes #17926.
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856adf54 by Ben Gamari at 2020-05-23T13:40:21-04:00
users-guide: Clarify meaning of -haddock flag
Fixes #18206.
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7ae57afd by Ben Gamari at 2020-05-23T13:41:03-04:00
git: Add ignored commits file
This can be used to tell git to ignore bulk renaming commits like the
recently-finished module hierarchy refactoring. Configured with,
git config blame.ignoreRevsFile .git-ignore-revs
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63d30e60 by jneira at 2020-05-24T01:54:42-04:00
Add hie-bios script for windows systems
It is a direct translation of the sh script
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59182b88 by jneira at 2020-05-24T01:54:42-04:00
Honour previous values for CABAL and CABFLAGS
The immediate goal is let the hie-bios.bat script
set CABFLAGS with `-v0` and remove all cabal output
except the compiler arguments
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932dc54e by jneira at 2020-05-24T01:54:42-04:00
Add specific configuration for windows in hie.yaml
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e0eda070 by jneira at 2020-05-24T01:54:42-04:00
Remove not needed hie-bios output
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a0ea59d6 by Sylvain Henry at 2020-05-24T01:55:24-04:00
Move Config module into GHC.Settings
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37430251 by Sylvain Henry at 2020-05-24T01:55:24-04:00
Rename GHC.Core.Arity into GHC.Core.Opt.Arity
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a426abb9 by Sylvain Henry at 2020-05-24T01:55:24-04:00
Rename GHC.Hs.Types into GHC.Hs.Type
See discussion in https://gitlab.haskell.org/ghc/ghc/issues/13009#note_268610
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1c91a7a0 by Sylvain Henry at 2020-05-24T01:55:24-04:00
Bump haddock submodule
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66bd24d1 by Ryan Scott at 2020-05-24T01:56:03-04:00
Add orderingTyCon to wiredInTyCons (#18185)
`Ordering` needs to be wired in for use in the built-in `CmpNat` and
`CmpSymbol` type families, but somehow it was never added to the list
of `wiredInTyCons`, leading to the various oddities observed
in #18185. Easily fixed by moving `orderingTyCon` from
`basicKnownKeyNames` to `wiredInTyCons`.
Fixes #18185.
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01c43634 by Matthew Pickering at 2020-05-24T01:56:42-04:00
Remove unused hs-boot file
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7a07aa71 by Sylvain Henry at 2020-05-24T15:22:17-04:00
Hadrian: fix cross-compiler build (#16051)
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15ccca16 by Sylvain Henry at 2020-05-24T15:22:17-04:00
Hadrian: fix distDir per stage
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b420fb24 by Sylvain Henry at 2020-05-24T15:22:17-04:00
Hadrian: fix hp2ps error during cross-compilation
Fixed by @alp (see https://gitlab.haskell.org/ghc/ghc/issues/16051#note_274265)
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cd339ef0 by Joshua Price at 2020-05-24T15:22:56-04:00
Make Unicode brackets opening/closing tokens (#18225)
The tokens `[|`, `|]`, `(|`, and `|)` are opening/closing tokens as
described in GHC Proposal #229. This commit makes the unicode
variants (`⟦`, `⟧`, `⦇`, and `⦈`) act the same as their ASCII
counterparts.
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013d7120 by Ben Gamari at 2020-05-25T09:48:17-04:00
Revert "Specify kind variables for inferred kinds in base."
As noted in !3132, this has rather severe knock-on consequences in
user-code. We'll need to revisit this before merging something along
these lines.
This reverts commit 9749fe1223d182b1f8e7e4f7378df661c509f396.
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4c4312ed by Ben Gamari at 2020-05-25T09:48:53-04:00
Coverage: Drop redundant ad-hoc boot module check
To determine whether the module is a boot module
Coverage.addTicksToBinds was checking for a `boot` suffix in the module
source filename. This is quite ad-hoc and shouldn't be necessary; the
callsite in `deSugar` already checks that the module isn't a boot
module.
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1abf3c84 by Ben Gamari at 2020-05-25T09:48:53-04:00
Coverage: Make tickBoxCount strict
This could otherwise easily cause a leak of (+) thunks.
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b2813750 by Ben Gamari at 2020-05-25T09:48:53-04:00
Coverage: Make ccIndices strict
This just seems like a good idea.
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02e278eb by Ben Gamari at 2020-05-25T09:48:53-04:00
Coverage: Don't produce ModBreaks if not HscInterpreted
emptyModBreaks contains a bottom and consequently it's important that we
don't use it unless necessary.
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b8c014ce by Ben Gamari at 2020-05-25T09:48:53-04:00
Coverage: Factor out addMixEntry
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53814a64 by Zubin Duggal at 2020-05-26T03:03:24-04:00
Add info about typeclass evidence to .hie files
See `testsuite/tests/hiefile/should_run/HieQueries.hs` and
`testsuite/tests/hiefile/should_run/HieQueries.stdout` for an example of this
We add two new fields, `EvidenceVarBind` and `EvidenceVarUse` to the
`ContextInfo` associated with an Identifier. These are associated with the
appropriate identifiers for the evidence variables collected when we come across
`HsWrappers`, `TcEvBinds` and `IPBinds` while traversing the AST.
Instance dictionary and superclass selector dictionaries from `tcg_insts` and
classes defined in `tcg_tcs` are also recorded in the AST as originating from
their definition span
This allows us to save a complete picture of the evidence constructed by the
constraint solver, and will let us report this to the user, enabling features
like going to the instance definition from the invocation of a class method(or
any other method taking a constraint) and finding all usages of a particular
instance.
Additionally,
- Mark NodeInfo with an origin so we can differentiate between bindings
origininating in the source vs those in ghc
- Along with typeclass evidence info, also include information on Implicit
Parameters
- Add a few utility functions to HieUtils in order to query the new info
Updates haddock submodule
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6604906c by Sebastian Graf at 2020-05-26T03:04:04-04:00
Make WorkWrap.Lib.isWorkerSmallEnough aware of the old arity
We should allow a wrapper with up to 82 parameters when the original
function had 82 parameters to begin with.
I verified that this made no difference on NoFib, but then again
it doesn't use huge records...
Fixes #18122.
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cf772f19 by Sylvain Henry at 2020-05-26T03:04:45-04:00
Enhance Note [About units] for Backpack
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ede24126 by Takenobu Tani at 2020-05-27T00:13:55-04:00
core-spec: Modify file paths according to new module hierarchy
This patch updates file paths according to new module hierarchy [1]:
* GHC/Core.hs <= coreSyn/CoreSyn.hs
* GHC/Core/Coercion.hs <= types/Coercion.hs
* GHC/Core/Coercion/Axiom.hs <= types/CoAxiom.hs
* GHC/Core/Coercion/Opt.hs <= types/OptCoercion.hs
* GHC/Core/DataCon.hs <= basicTypes/DataCon.hs
* GHC/Core/FamInstEnv.hs <= types/FamInstEnv.hs
* GHC/Core/Lint.hs <= coreSyn/CoreLint.hs
* GHC/Core/Subst.hs <= coreSyn/CoreSubst.hs
* GHC/Core/TyCo/Rep.hs <= types/TyCoRep.hs
* GHC/Core/TyCon.hs <= types/TyCon.hs
* GHC/Core/Type.hs <= types/Type.hs
* GHC/Core/Unify.hs <= types/Unify.hs
* GHC/Types/Literal.hs <= basicTypes/Literal.hs
* GHC/Types/Var.hs <= basicTypes/Var.hs
[1]: https://gitlab.haskell.org/ghc/ghc/-/wikis/Make-GHC-codebase-more-modular
[skip ci]
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04750304 by Ben Gamari at 2020-05-27T00:14:33-04:00
eventlog: Fix racy flushing
Previously no attempt was made to avoid multiple threads writing their
capability-local eventlog buffers to the eventlog writer simultaneously.
This could result in multiple eventlog streams being interleaved. Fix
this by documenting that the EventLogWriter's write() and flush()
functions may be called reentrantly and fix the default writer to
protect its FILE* by a mutex.
Fixes #18210.
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d6203f24 by Joshua Price at 2020-05-27T00:15:17-04:00
Make `identifier` parse unparenthesized `->` (#18060)
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28deee28 by Ben Gamari at 2020-05-28T16:23:21-04:00
GHC.Core.Unfold: Refactor traceInline
This reduces duplication as well as fixes a bug wherein -dinlining-check
would override -ddump-inlinings. Moreover, the new variant
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1f393e1e by Ben Gamari at 2020-05-28T16:23:21-04:00
Avoid unnecessary allocations due to tracing utilities
While ticky-profiling the typechecker I noticed that hundreds of
millions of SDocs are being allocated just in case -ddump-*-trace is
enabled. This is awful.
We avoid this by ensuring that the dump flag check is inlined into the
call site, ensuring that the tracing document needn't be allocated
unless it's actually needed.
See Note [INLINE conditional tracing utilities] for details.
Fixes #18168.
Metric Decrease:
T9961
haddock.Cabal
haddock.base
haddock.compiler
- - - - -
5f621a78 by Vladislav Zavialov at 2020-05-28T16:23:58-04:00
Add Semigroup/Monoid for Q (#18123)
- - - - -
dc5f004c by Xavier Denis at 2020-05-28T16:24:37-04:00
Fix #18071
Run the core linter on candidate instances to ensure they are
well-kinded.
Better handle quantified constraints by using a CtWanted to avoid
having unsolved constraints thrown away at the end by the solver.
- - - - -
10e6982c by Sebastian Graf at 2020-05-28T16:25:14-04:00
FloatOut: Only eta-expand dead-end RHS if arity will increase (#18231)
Otherwise we risk turning trivial RHS into non-trivial RHS, introducing
unnecessary bindings in the next Simplifier run, resulting in more
churn.
Fixes #18231.
- - - - -
08dab5f7 by Sebastian Graf at 2020-05-28T16:25:14-04:00
DmdAnal: Recognise precise exceptions from case alternatives (#18086)
Consider
```hs
m :: IO ()
m = do
putStrLn "foo"
error "bar"
```
`m` (from #18086) always throws a (precise or imprecise) exception or
diverges. Yet demand analysis infers `<L,A>` as demand signature instead
of `<L,A>x` for it.
That's because the demand analyser sees `putStrLn` occuring in a case
scrutinee and decides that it has to `deferAfterPreciseException`,
because `putStrLn` throws a precise exception on some control flow
paths. This will mask the `botDiv` `Divergence`of the single case alt
containing `error` to `topDiv`. Since `putStrLn` has `topDiv` itself,
the final `Divergence` is `topDiv`.
This is easily fixed: `deferAfterPreciseException` works by `lub`ing
with the demand type of a virtual case branch denoting the precise
exceptional control flow. We used `nopDmdType` before, but we can be
more precise and use `exnDmdType`, which is `nopDmdType` with `exnDiv`.
Now the `Divergence` from the case alt will degrade `botDiv` to `exnDiv`
instead of `topDiv`, which combines with the result from the scrutinee
to `exnDiv`, and all is well.
Fixes #18086.
- - - - -
aef95f11 by Ben Gamari at 2020-05-28T16:25:53-04:00
Ticky-ticky: Record DataCon name in ticker name
This makes it significantly easier to spot the nature of
allocations regressions and comes at a reasonably low cost.
- - - - -
8f021b8c by Ben Gamari at 2020-05-28T16:26:34-04:00
hadrian: Don't track GHC's verbosity argument
Teach hadrian to ignore GHC's -v argument in its recompilation check,
thus fixing #18131.
- - - - -
13d9380b by Ben Gamari at 2020-05-28T16:27:20-04:00
Rip out CmmStackInfo(updfr_space)
As noted in #18232, this field is currently completely unused and
moreover doesn't have a clear meaning.
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f10d11fa by Andreas Klebinger at 2020-05-29T01:38:42-04:00
Fix "build/elem" RULE.
An redundant constraint prevented the rule from matching.
Fixing this allows a call to elem on a known list to be translated
into a series of equality checks, and eventually a simple case
expression.
Surprisingly this seems to regress elem for strings. To avoid
this we now also allow foldrCString to inline and add an UTF8
variant. This results in elem being compiled to a tight
non-allocating loop over the primitive string literal which
performs a linear search.
In the process this commit adds UTF8 variants for some of the
functions in GHC.CString. This is required to make this work for
both ASCII and UTF8 strings.
There are also small tweaks to the CString related rules.
We now allow ourselfes the luxury to compare the folding function
via eqExpr, which helps to ensure the rule fires before we inline
foldrCString*. Together with a few changes to allow matching on both
the UTF8 and ASCII variants of the CString functions.
- - - - -
bbeb2389 by Ben Gamari at 2020-05-29T01:39:19-04:00
CoreToStg: Add Outputable ArgInfo instance
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0e3361ca by Simon Peyton Jones at 2020-05-29T01:39:19-04:00
Make Lint check return type of a join point
Consider
join x = rhs in body
It's important that the type of 'rhs' is the same as the type of
'body', but Lint wasn't checking that invariant.
Now it does! This was exposed by investigation into !3113.
- - - - -
c49f7df0 by Simon Peyton Jones at 2020-05-29T01:39:19-04:00
Do not float join points in exprIsConApp_maybe
We hvae been making exprIsConApp_maybe cleverer in recent times:
commit b78cc64e923716ac0512c299f42d4d0012306c05
Date: Thu Nov 15 17:14:31 2018 +0100
Make constructor wrappers inline only during the final phase
commit 7833cf407d1f608bebb1d38bb99d3035d8d735e6
Date: Thu Jan 24 17:58:50 2019 +0100
Look through newtype wrappers (Trac #16254)
commit c25b135ff5b9c69a90df0ccf51b04952c2dc6ee1
Date: Thu Feb 21 12:03:22 2019 +0000
Fix exprIsConApp_maybe
But alas there was still a bug, now immortalised in
Note [Don't float join points]
in SimpleOpt.
It's quite hard to trigger because it requires a dead
join point, but it came up when compiling Cabal
Cabal.Distribution.Fields.Lexer.hs, when working on
!3113.
Happily, the fix is extremly easy. Finding the
bug was not so easy.
- - - - -
46720997 by Ben Gamari at 2020-05-29T01:39:19-04:00
Allow simplification through runRW#
Because runRW# inlines so late, we were previously able to do very
little simplification across it. For instance, given even a simple
program like
case runRW# (\s -> let n = I# 42# in n) of
I# n# -> f n#
we previously had no way to avoid the allocation of the I#.
This patch allows the simplifier to push strict contexts into the
continuation of a runRW# application, as explained in
in Note [Simplification of runRW#] in GHC.CoreToStg.Prep.
Fixes #15127.
Metric Increase:
T9961
Metric Decrease:
ManyConstructors
Co-Authored-By: Simon Peyton-Jone <simonpj at microsoft.com>
- - - - -
277c2f26 by Ben Gamari at 2020-05-29T01:39:55-04:00
Eta expand un-saturated primops
Now since we no longer try to predict CAFfyness we have no need for the
solution to #16846. Eta expanding unsaturated primop applications is
conceptually simpler, especially in the presence of levity polymorphism.
This essentially reverts cac8dc9f51e31e4c0a6cd9bc302f7e1bc7c03beb,
as suggested in #18079.
Closes #18079.
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f44d7ae0 by Simon Jakobi at 2020-05-29T01:40:34-04:00
base: Scrap deprecation plan for Data.Monoid.{First,Last}
See the discussion on the libraries mailing list for context:
https://mail.haskell.org/pipermail/libraries/2020-April/030357.html
- - - - -
8b494895 by Jeremy Schlatter at 2020-05-29T01:41:12-04:00
Fix typo in documentation
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998450f4 by Gleb Popov at 2020-05-29T01:41:53-04:00
Always define USE_PTHREAD_FOR_ITIMER for FreeBSD.
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f9a513e0 by Alp Mestanogullari at 2020-05-29T01:42:36-04:00
hadrian: introduce 'install' target
Its logic is very simple. It `need`s the `binary-dist-dir` target
and runs suitable `configure` and `make install` commands for the
user. A new `--prefix` command line argument is introduced to
specify where GHC should be installed.
- - - - -
67738db1 by Travis Whitaker at 2020-05-29T13:34:48-04:00
Build a threaded stage 1 if the bootstrapping GHC supports it.
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aac19e6c by Peter Trommler at 2020-05-29T13:35:24-04:00
PPC NCG: No per-symbol .section ".toc" directives
All position independent symbols are collected during code generation
and emitted in one go. Prepending each symbol with a .section ".toc"
directive is redundant. This patch drops the per-symbol directives
leading to smaller assembler files.
Fixes #18250
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4413828b by Ben Gamari at 2020-05-30T06:07:31-04:00
rts: Teach getNumProcessors to return available processors
Previously we would report the number of physical processors, which
can be quite wrong in a containerized setting. Now we rather return how
many processors are in our affinity mask when possible.
I also refactored the code to prefer platform-specific since this will
report logical CPUs instead of physical (using
`machdep.cpu.thread_count` on Darwin and `cpuset_getaffinity` on FreeBSD).
Fixes #14781.
- - - - -
1449435c by Ben Gamari at 2020-05-30T06:07:31-04:00
users-guide: Note change in getNumProcessors in users guide
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3d960169 by Ben Gamari at 2020-05-30T06:07:31-04:00
rts: Drop compatibility shims for Windows Vista
We can now assume that the thread and processor group interfaces are
available.
- - - - -
7f8f948c by Peter Trommler at 2020-05-30T06:08:07-04:00
PPC NCG: Fix .size directive on powerpc64 ELF v1
Thanks to Sergei Trofimovich for pointing out the issue.
Fixes #18237
- - - - -
7c555b05 by Andreas Klebinger at 2020-05-30T06:08:43-04:00
Optimize GHC.Utils.Monad.
Many functions in this module are recursive and as such are marked
loop breakers. Which means they are unlikely to get an unfolding.
This is *bad*. We always want to specialize them to specific Monads.
Which requires a visible unfolding at the use site.
I rewrote the recursive ones from:
foo f x = ... foo x' ...
to
foo f x = go x
where
go x = ...
As well as giving some pragmas to make all of them available
for specialization.
The end result is a reduction of allocations of about -1.4% for
nofib/spectral/simple/Main.hs when compiled with `-O`.
-------------------------
Metric Decrease:
T12425
T14683
T5631
T9233
T9675
T9961
WWRec
-------------------------
- - - - -
8b1cb5df by Ben Gamari at 2020-05-30T06:09:20-04:00
Windows: Bump Windows toolchain to 0.2
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6947231a by Zubin Duggal at 2020-05-30T06:10:02-04:00
Simplify contexts in GHC.Iface.Ext.Ast
- - - - -
2ee4f36c by Daniel Gröber at 2020-06-01T06:32:56-04:00
Cleanup OVERWRITING_CLOSURE logic
The code is just more confusing than it needs to be. We don't need to mix
the threaded check with the ldv profiling check since ldv's init already
checks for this. Hence they can be two separate checks. Taking the sanity
checking into account is also cleaner via DebugFlags.sanity. No need for
checking the DEBUG define.
The ZERO_SLOP_FOR_LDV_PROF and ZERO_SLOP_FOR_SANITY_CHECK definitions the
old code had also make things a lot more opaque IMO so I removed those.
- - - - -
6159559b by Daniel Gröber at 2020-06-01T06:32:56-04:00
Fix OVERWRITING_CLOSURE assuming closures are not inherently used
The new ASSERT in LDV_recordDead() was being tripped up by MVars when
removeFromMVarBlockedQueue() calls OVERWRITING_CLOSURE() via
OVERWRITE_INFO().
- - - - -
38992085 by Daniel Gröber at 2020-06-01T06:32:56-04:00
Always zero shrunk mutable array slop when profiling
When shrinking arrays in the profiling way we currently don't always zero
the leftover slop. This means we can't traverse such closures in the heap
profiler. The old Note [zeroing slop] and #8402 have some rationale for why
this is so but I belive the reasoning doesn't apply to mutable
closures. There users already have to ensure multiple threads don't step on
each other's toes so zeroing should be safe.
- - - - -
b0c1f2a6 by Ben Gamari at 2020-06-01T06:33:37-04:00
testsuite: Add test for #18151
- - - - -
9a99a178 by Ben Gamari at 2020-06-01T06:33:37-04:00
testsuite: Add test for desugaring of PostfixOperators
- - - - -
2b89ca5b by Ben Gamari at 2020-06-01T06:33:37-04:00
HsToCore: Eta expand left sections
Strangely, the comment next to this code already alluded to the fact
that even simply eta-expanding will sacrifice laziness. It's quite
unclear how we regressed so far.
See #18151.
- - - - -
d412d7a3 by Kirill Elagin at 2020-06-01T06:34:21-04:00
Winferred-safe-imports: Do not exit with error
Currently, when -Winferred-safe-imports is enabled, even when it is not
turned into an error, the compiler will still exit with exit code 1 if
this warning was emitted.
Make sure it is really treated as a warning.
- - - - -
f945eea5 by Ben Gamari at 2020-06-01T06:34:58-04:00
nonmoving: Optimise log2_ceil
- - - - -
aab606e4 by Bodigrim at 2020-06-01T06:35:36-04:00
Clarify description of fromListN
- - - - -
7e5220e2 by Bodigrim at 2020-06-01T06:35:36-04:00
Apply suggestion to libraries/base/GHC/Exts.hs
- - - - -
f3fb1ce9 by fendor at 2020-06-01T06:36:18-04:00
Add `isInScope` check to `lintCoercion`
Mirrors the behaviour of `lintType`.
- - - - -
5ac4d946 by fendor at 2020-06-01T06:36:18-04:00
Lint rhs of IfaceRule
- - - - -
1cef6126 by Jeremy Schlatter at 2020-06-01T06:37:00-04:00
Fix wording in documentation
The duplicate "orphan instance" phrase here doesn't make sense, and was
probably an accident.
- - - - -
5aaf08f2 by Takenobu Tani at 2020-06-01T06:37:43-04:00
configure: Modify aclocal.m4 according to new module hierarchy
This patch updates file paths according to new module hierarchy [1]:
* Rename:
* compiler/GHC/Parser.hs <= compiler/parser/Parser.hs
* compiler/GHC/Parser/Lexer.hs <= compiler/Parser/Lexer.hs
* Add:
* compiler/GHC/Cmm/Lexer.hs
[1]: https://gitlab.haskell.org/ghc/ghc/-/wikis/Make-GHC-codebase-more-modular
- - - - -
15857ad8 by Ben Gamari at 2020-06-01T06:38:26-04:00
testsuite: Don't fail if we can't unlink __symlink_test
Afterall, it's possible we were unable to create it due to lack of
symlink permission.
- - - - -
4a7229ef by Ben Gamari at 2020-06-01T06:38:26-04:00
testsuite: Refactor ghostscript detection
Tamar reported that he saw crashes due to unhandled exceptions.
- - - - -
2ab37eaf by Ben Gamari at 2020-06-01T06:38:26-04:00
testsuite/perf_notes: Fix ill-typed assignments
- - - - -
e45d5b66 by Ben Gamari at 2020-06-01T06:38:26-04:00
testsuite/testutil: Fix bytes/str mismatch
- - - - -
7002d0cb by Ben Gamari at 2020-06-01T06:38:26-04:00
testsuite: Work around spurious mypy failure
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11390e3a by Takenobu Tani at 2020-06-01T06:39:05-04:00
Clean up file paths for new module hierarchy
This updates comments only.
This patch replaces file references according to new module hierarchy.
See also:
* https://gitlab.haskell.org/ghc/ghc/-/wikis/Make-GHC-codebase-more-modular
* https://gitlab.haskell.org/ghc/ghc/issues/13009
- - - - -
8f2e5732 by Takenobu Tani at 2020-06-01T06:39:05-04:00
Modify file paths to module paths for new module hierarchy
This updates comments only.
This patch replaces module references according to new module
hierarchy [1][2].
For files under the `compiler/` directory, I replace them as
module paths instead of file paths. For instance,
`GHC.Unit.State` instead of `compiler/GHC/Unit/State.hs` [3].
For current and future haddock's markup, this patch encloses
the module name with "" [4].
[1]: https://gitlab.haskell.org/ghc/ghc/-/wikis/Make-GHC-codebase-more-modular
[2]: https://gitlab.haskell.org/ghc/ghc/issues/13009
[3]: https://gitlab.haskell.org/ghc/ghc/-/merge_requests/3375#note_276613
[4]: https://haskell-haddock.readthedocs.io/en/latest/markup.html#linking-to-modules
- - - - -
68b71c4a by Tom Ellis at 2020-06-01T06:39:55-04:00
Rename the singleton tuple GHC.Tuple.Unit to GHC.Tuple.Solo
- - - - -
95da76c2 by Sylvain Henry at 2020-06-01T06:40:41-04:00
Hadrian: fix binary-dist target for cross-compilation
- - - - -
730fcd54 by Vladislav Zavialov at 2020-06-01T06:41:18-04:00
Improve parser error messages for the @-operator
Since GHC diverges from the Haskell Report by allowing the user
to define (@) as an infix operator, we better give a good
error message when the user does so unintentionally.
In general, this is rather hard to do, as some failures will be
discovered only in the renamer or the type checker:
x :: (Integer, Integer)
x @ (a, b) = (1, 2)
This patch does *not* address this general case.
However, it gives much better error messages when the binding
is not syntactically valid:
pairs xs @ (_:xs') = zip xs xs'
Before this patch, the error message was rather puzzling:
<interactive>:1:1: error: Parse error in pattern: pairs
After this patch, the error message includes a hint:
<interactive>:1:1: error:
Parse error in pattern: pairs
In a function binding for the ‘@’ operator.
Perhaps you meant an as-pattern, which must not be surrounded by whitespace
- - - - -
0fde5377 by Vladislav Zavialov at 2020-06-01T06:41:18-04:00
Improve parser error messages for TypeApplications
With this patch, we always parse f @t as a type application,
thereby producing better error messages.
This steals two syntactic forms:
* Prefix form of the @-operator in expressions. Since the @-operator is
a divergence from the Haskell Report anyway, this is not a major loss.
* Prefix form of @-patterns. Since we are stealing loose infix form
anyway, might as well sacrifice the prefix form for the sake of much
better error messages.
- - - - -
c68e7e1e by Vladislav Zavialov at 2020-06-01T06:41:18-04:00
Improve parser error messages for TemplateHaskellQuotes
While [e| |], [t| |], [d| |], and so on, steal syntax from list
comprehensions, [| |] and [|| ||] do not steal any syntax.
Thus we can improve error messages by always accepting them in the
lexer. Turns out the renamer already performs necessary validation.
- - - - -
120aedbd by Ben Gamari at 2020-06-01T16:07:02-04:00
gitlab-ci: Disable use of ld.lld on ARMv7
It turns out that lld non-deterministically fails on ARMv7. I suspect
this may be due to the a kernel regression as this only started
happening when we upgraded to 5.4. Nevertheless, easily avoided by
simply sticking with gold.
Works around #18280.
- - - - -
58c54286 by Tamar Christina at 2020-06-02T12:16:21+02:00
winio: Add Atomic Exchange PrimOp and implement Atomic Ptr exchanges.
The initial version was rewritten by Tamar Christina.
It was rewritten in large parts by Andreas Klebinger.
Co-authored-by: Andreas Klebinger <klebinger.andreas at gmx.at>
- - - - -
30 changed files:
- + .git-ignore-revs
- .gitlab-ci.yml
- .gitlab/ci.sh
- .gitlab/merge_request_templates/merge-request.md
- aclocal.m4
- compiler/GHC.hs
- compiler/GHC/Builtin/Names.hs
- − compiler/GHC/Builtin/Names.hs-boot
- compiler/GHC/Builtin/Names/TH.hs
- compiler/GHC/Builtin/PrimOps.hs
- compiler/GHC/Builtin/Types.hs
- compiler/GHC/Builtin/Utils.hs
- compiler/GHC/Builtin/primops.txt.pp
- compiler/GHC/ByteCode/Linker.hs
- compiler/GHC/Cmm.hs
- compiler/GHC/Cmm/CLabel.hs
- compiler/GHC/Cmm/LayoutStack.hs
- compiler/GHC/Cmm/MachOp.hs
- compiler/GHC/Cmm/Opt.hs
- compiler/GHC/Cmm/Parser.y
- compiler/GHC/Cmm/Ppr.hs
- compiler/GHC/Cmm/ProcPoint.hs
- compiler/GHC/Cmm/Utils.hs
- compiler/GHC/CmmToAsm.hs
- compiler/GHC/CmmToAsm/BlockLayout.hs
- compiler/GHC/CmmToAsm/CFG.hs
- compiler/GHC/CmmToAsm/CPrim.hs
- compiler/GHC/CmmToAsm/Dwarf.hs
- compiler/GHC/CmmToAsm/Instr.hs
- compiler/GHC/CmmToAsm/PIC.hs
The diff was not included because it is too large.
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/97fd7e201f7cfbed2165e718ad2c89b6e4c31096...58c54286d999a929a0835d2a7816dd91287cca84
--
View it on GitLab: https://gitlab.haskell.org/ghc/ghc/-/compare/97fd7e201f7cfbed2165e718ad2c89b6e4c31096...58c54286d999a929a0835d2a7816dd91287cca84
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