| Commit message (Collapse) | Author | Age | Files | Lines |
|---|
| | |
|
| |
|
|
|
| |
This simply runs the compile_and_run tests with `-xn`, enabling the
nonmoving oldest generation.
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
This implements the core heap structure and a serial mark/sweep
collector which can be used to manage the oldest-generation heap.
This is the first step towards a concurrent mark-and-sweep collector
aimed at low-latency applications.
The full design of the collector implemented here is described in detail
in a technical note
B. Gamari. "A Concurrent Garbage Collector For the Glasgow Haskell
Compiler" (2018)
The basic heap structure used in this design is heavily inspired by
K. Ueno & A. Ohori. "A fully concurrent garbage collector for
functional programs on multicore processors." /ACM SIGPLAN Notices/
Vol. 51. No. 9 (presented by ICFP 2016)
This design is intended to allow both marking and sweeping
concurrent to execution of a multi-core mutator. Unlike the Ueno design,
which requires no global synchronization pauses, the collector
introduced here requires a stop-the-world pause at the beginning and end
of the mark phase.
To avoid heap fragmentation, the allocator consists of a number of
fixed-size /sub-allocators/. Each of these sub-allocators allocators into
its own set of /segments/, themselves allocated from the block
allocator. Each segment is broken into a set of fixed-size allocation
blocks (which back allocations) in addition to a bitmap (used to track
the liveness of blocks) and some additional metadata (used also used
to track liveness).
This heap structure enables collection via mark-and-sweep, which can be
performed concurrently via a snapshot-at-the-beginning scheme (although
concurrent collection is not implemented in this patch).
The mark queue is a fairly straightforward chunked-array structure.
The representation is a bit more verbose than a typical mark queue to
accomodate a combination of two features:
* a mark FIFO, which improves the locality of marking, reducing one of
the major overheads seen in mark/sweep allocators (see [1] for
details)
* the selector optimization and indirection shortcutting, which
requires that we track where we found each reference to an object
in case we need to update the reference at a later point (e.g. when
we find that it is an indirection). See Note [Origin references in
the nonmoving collector] (in `NonMovingMark.h`) for details.
Beyond this the mark/sweep is fairly run-of-the-mill.
[1] R. Garner, S.M. Blackburn, D. Frampton. "Effective Prefetch for
Mark-Sweep Garbage Collection." ISMM 2007.
Co-Authored-By: Ben Gamari <ben@well-typed.com>
|
| | |
|
| |
|
|
| |
This flag will enable the use of a non-moving oldest generation.
|
| |
|
|
|
|
|
| |
To keep the non-moving collector nicely separated from the moving
collector its scavenging phase will live in another file,
`NonMovingScav.c`. However, it will need to use these functions so
let's expose them.
|
| |
|
|
|
| |
This warning is a bit of a relic; there is little reason to avoid
aggregate return values in 2019.
|
| |
|
|
|
| |
These will be needed when we implement sweeping in the nonmoving
collector.
|
| |\ \
| | |
| | |
| | | |
'wip/gc/aligned-block-allocation' into wip/gc/preparation
|
| | | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | |
| | | |
This implements support for block group allocations which are aligned to
an integral number of blocks.
This will be used by the nonmoving garbage collector, which uses the
block allocator to allocate the segments which back its heap. These
segments are a fixed number of blocks in size, with each segment being
aligned to the segment size boundary. This allows us to easily find the
segment metadata stored at the beginning of the segment.
|
| | |/
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| |
| | |
The concurrent mark-and-sweep will be performed by a GHC task which will
not hold a capability. This is necessary to avoid a concurrent mark from
interfering with minor generation collections.
However, the major collector must synchronize with the mutators at the
end of marking to flush their update remembered sets. This patch extends
the `requestSync` mechanism used to synchronize garbage collectors to
allow synchronization without holding a capability.
This change is fairly straightforward as the capability was previously
only required for two reasons:
1. to ensure that we don't try to re-acquire a capability that we
the sync requestor already holds.
2. to provide a way to suspend and later resume the sync request if
there is already a sync pending.
When synchronizing without holding a capability we needn't worry about
consideration (1) at all.
(2) is slightly trickier and may happen, for instance, when a capability
requests a minor collection and shortly thereafter the non-moving mark
thread requests a post-mark synchronization. In this case we need to
ensure that the non-moving mark thread suspends his request until after
the minor GC has concluded to avoid dead-locking. For this we introduce
a condition variable, `sync_finished_cond`, which a
non-capability-bearing requestor will wait on and which is signalled
after a synchronization or GC has finished.
|
| | | |
|
| | | |
|
| | |
| |
| |
| |
| | |
This were previously quite unclear and will change a bit under the
non-moving collector so let's clear this up now.
|
| | | |
|
| | |
| |
| |
| | |
This was slightly non-obvious so a note seems deserved.
|
| |/
|
|
|
|
|
| |
Namely ensure that block descriptors are initialized with valid
generation numbers.
Co-Authored-By: Ben Gamari <ben@well-typed.com>
|
| |
|
|
|
| |
This ensures that all testsuite way names given to `omit_ways`,
`only_ways`, etc. are known ways.
|
| | |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
Previously `makefile_test` and `run_command` tests could easily end up
in a situation where they wouldn't be run if the user used the
`only_ways` modifier. The reason is to build the set of a ways to run
the test in we first start with a candidate set determined by the test
type (e.g. `makefile_test`, `compile_run`, etc.) and then filter that
set with the constraints given by the test's modifiers.
`makefile_test` and `run_command` tests' candidate sets were simply
`{normal}`, and consequently most uses of `only_ways` would result in
the test being never run.
To avoid this we rather use all ways as the candidate sets for these
test types. This may result in a few more testcases than we would like
(given that some `run_command` tests are insensitive to way) but this
can be fixed by adding modifiers and we would much rather run too many
tests than too few.
This fixes #16042 and a number of other tests afflicted by the same issue.
However, there were a few cases that required special attention:
* `T14028` is currently failing and is therefore marked as broken due
to #17300
* `T-signals-child` is fragile in the `threaded1` and `threaded2` ways
(tracked in #17307)
|
| | |
|
| | |
|
| |
|
|
| |
Also refactor things a bit to eliminate repetition.
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
This introduces three new modules:
- basicTypes/Predicate.hs describes predicates, moving
this logic out of Type. Predicates don't really exist
in Core, and so don't belong in Type.
- typecheck/TcOrigin.hs describes the origin of constraints
and types. It was easy to remove from other modules and
can often be imported instead of other, scarier modules.
- typecheck/Constraint.hs describes constraints as used in
the solver. It is taken from TcRnTypes.
No work other than module splitting is in this patch.
This is the first step toward homogeneous equality, which will
rely more strongly on predicates. And homogeneous equality is the
next step toward a dependently typed core language.
|
| |
|
|
|
| |
It came back to life in 381c3ae31b68019177f1cd20cb4da2f9d3b7d6c6 by
mistake.
|
| |
|
|
|
|
|
|
|
|
|
|
|
| |
In #17343 we saw that we didn't handle the pattern guard `!_ <-
undefined` correctly: The `undefined` was never evaluated. Indeed,
elaboration failed to insert the invisible type aruments to `undefined`.
So `undefined` was trivially a normal-form and in turn never entered.
The problem is that we used to infer a sigma-type for the RHS of the
guard, the leading qualifiers of which will never be useful in a pattern
match situation. Hence we infer a rho-type now.
Fixes #17343.
|
| |
|
|
|
|
|
|
| |
This is a test for the current algorithm of GHCi command name resolution.
I add this test in preparation for updating GHCi command name resolution.
For the current algorithm, see https://downloads.haskell.org/ghc/latest/docs/html/users_guide/ghci.html#the-ghci-files
|
| | |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
For backends maintaining the CFG during codegen
we can now find loops and their nesting level.
This is based on the Cmm CFG and dominator analysis.
As a result we can estimate edge frequencies a lot better
for methods, resulting in far better code layout.
Speedup on nofib: ~1.5%
Increase in compile times: ~1.9%
To make this feasible this commit adds:
* Dominator analysis based on the Lengauer-Tarjan Algorithm.
* An algorithm estimating global edge frequences from branch
probabilities - In CFG.hs
A few static branch prediction heuristics:
* Expect to take the backedge in loops.
* Expect to take the branch NOT exiting a loop.
* Expect integer vs constant comparisons to be false.
We also treat heap/stack checks special for branch prediction
to avoid them being treated as loops.
|
| |
|
|
| |
Fixes #17351.
|
| | |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
Issue #17355 occurred because the control flow for
`TcValidity.check_valid_inst_head` was structured in such a way that
whenever it checked a special, built-in class (like `Generic` or
`HasField`), it would skip the most important check of all:
`checkValidTypePats`, which rejects nonsense like this:
```hs
instance Generic (forall a. a)
```
This fixes the issue by carving out `checkValidTypePats` from
`check_valid_inst_head` so that `checkValidTypePats` is always
invoked. `check_valid_inst_head` has also been renamed to
`check_special_inst_head` to reflect its new purpose of _only_
checking for instances headed by special classes.
Fixes #17355.
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
The latest installment in my quest to clean up the code in
`TcDeriv*`. This time, my sights are set on
`TcDerivInfer.inferConstraints`, which infers the context for derived
instances. This function is a wee bit awkward at the moment:
* It's not terribly obvious from a quick glance, but
`inferConstraints` is only ever invoked when using the `stock` or
`anyclass` deriving strategies, as the code for inferring the
context for `newtype`- or `via`-derived instances is located
separately in `mk_coerce_based_eqn`. But there's no good reason
for things to be this way, so I moved this code from
`mk_coerce_based_eqn` to `inferConstraints` so that everything
related to inferring instance contexts is located in one place.
* In this process, I discovered that the Haddocks for the auxiliary
function `inferConstraintsDataConArgs` are completely wrong. It
claims that it handles both `stock` and `newtype` deriving, but
this is completely wrong, as discussed above—it only handles
`stock`. To rectify this, I renamed this function to
`inferConstraintsStock` to reflect its actual purpose and created
a new `inferConstraintsCoerceBased` function to specifically
handle `newtype` (and `via`) deriving.
Doing this revealed some opportunities for further simplification:
* Removing the context-inference–related code from
`mk_coerce_based_eqn` made me realize that the overall structure
of the function is basically identical to `mk_originative_eqn`.
In fact, I was easily able to combine the two functions into a
single `mk_eqn_from_mechanism` function.
As part of this merger, I now invoke
`atf_coerce_based_error_checks` from `doDerivInstErrorChecks1`.
* I discovered that GHC defined this function:
```hs
typeToTypeKind = liftedTypeKind `mkVisFunTy` liftedTypeKind
```
No fewer than four times in different modules. I consolidated all
of these definitions in a single location in `TysWiredIn`.
|
| |
|
|
|
| |
This is a very cheap job and can catch a number of "easy" failure modes
(e.g. missing imports in the compiler). Let's run it first.
|
| |
|
|
|
|
|
|
| |
The fixes for these issues both have user-facing consequences, so it
would be good to mention them in the release notes for GHC 8.10.1.
While I'm in town, also mention `UnboxedSums` in the release notes
entry related to `-fobject-code`.
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
When the users guide fails to build (as in #17346), a
`docs/users_guide/.log` file will be generated with contents that
look something like this:
```
WARNING: unknown config value 'latex_paper_size' in override, ignoring
/home/rgscott/Software/ghc5/docs/users_guide/ghci.rst:3410: WARNING: u'ghc-flag' reference target not found: -pgmo ?option?
/home/rgscott/Software/ghc5/docs/users_guide/ghci.rst:3410: WARNING: u'ghc-flag' reference target not found: -pgmo ?port?
Encoding error:
'ascii' codec can't encode character u'\u27e8' in position 132: ordinal not in range(128)
The full traceback has been saved in /tmp/sphinx-err-rDF2LX.log, if you want to report the issue to the developers.
```
This definitely should not be checked in to version control, so let's
add this to `.gitignore`.
|
| | |
|
| |
|
|
|
|
|
| |
This commit explicitly adds description about double colon command
of GHCi.
[skip ci]
|
| |
|
|
|
|
|
|
|
|
|
|
|
| |
Statements can change the basic block in which instructions
are placed during instruction selection.
We have to keep track of this switch of the current basic block
as we need this information in order to properly update the CFG.
This commit implements this change and fixes #17334.
We do so by having stmtToInstr return the new block id
if a statement changed the basic block.
|
| | |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
GHC has a wonderful-but-delicate mechanism for building recursive
dictionaries by adding a goal to the "solved dictionaries" before
solving the sub-goals. See Note [Solved dictionaries] in TcSMonad
Ticket #17267 showed that if you use this mechanism for local
/quantified/ constraints you can get a loop -- or even unsafe
coerce. This patch fixes the bug.
Specifically
* Make TcSMonad.addSolvedDict be conditional on using a
/top level/ instance, not a quantified one.
* Moreover, we /also/ don't want to add a solved dict
for equalities (a~b).
* Add lots more comments to Note [Solved dictionaries]
to explain the above cryptic stuff.
* Extend InstanceWhat to identify those strange built-in
equality instances.
A couple of other things along the way
* Delete the unused Type.isIPPred_maybe.
* Stop making addSolvedDict conditional on not being an
impolicit parameter. This comes from way back. But
it's irrelevant now because IP dicts are never solved
via an instance.
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
GHC is suposed to uphold the principle that an /inferred/ type
for a let-binding should obey the rules for that module. E.g.
we should only accept an inferred higher rank type if we have
RankNTypes on.
But we were failing to check this: TcValidity.checkValidType
allowed arbitrary rank for inferred types.
This patch fixes the bug. It might in principle cause some breakage,
but if so that's good: the user should add RankNTypes and/or a
manual signature. (And almost every package has explicit user
signatures for all top-level things anyway.) Let's see.
Fixes #17213.
Metric Decrease:
T10370
|
| |
|
|
|
|
|
|
|
|
|
| |
Issue #17339 was caused by using a slightly different version of
`newDFunName` for derived instances that, confusingly enough, did not
take all arguments to the class into account when generating the
`DFun` name. I cannot think of any good reason for doing this, so
this patch uses `newDFunName` uniformly for both derived instances
and manually written instances alike.
Fixes #17339.
|
| |
|
|
|
|
|
|
|
|
|
|
|
| |
The CI job fails with:
+++ rts/T13676.run/T13676.run.stderr.normalised 2019-10-09 12:27:56.000000000 -0700
@@ -0,0 +1,4 @@
+dyld: Library not loaded: @rpath/libHShaskeline-0.7.5.0-ghc8.9.0.20191009.dylib
+ Referenced from: /Users/builder/builds/ewzE5N2p/0/ghc/ghc/inplace/lib/bin/ghc
+ Reason: image not found
+*** Exception: readCreateProcess: '/Users/builder/builds/ewzE5N2p/0/ghc/ghc/inplace/lib/bin/ghc' '-B/Users/builder/builds/ewzE5N2p/0/ghc/ghc/inplace/lib' '-e' ''/''$'/'' == '/''/x0024'/''' +RTS '-tT13676.t' (exit -6): failed
Unable to reproduce locally.
|
| | |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
- No need to distinguish between gcc-llvm and clang. First of all,
gcc-llvm is quite old and surely unmaintained by now. Second of all,
none of the code actually care about that distinction!
Now, it does make sense to consider C multiple frontends for LLVMs in
the form of clang vs clang-cl (same clang, yes, but tweaked
interface). But this is better handled in terms of "gccish vs
mvscish" and "is LLVM", yielding 4 combinations. Therefore, I don't
think it is useful saving the existing code for that.
- Get the remaining CC_LLVM_BACKEND, and also TABLES_NEXT_TO_CODE in
mk/config.h the normal way, rather than hacking it post-hoc. No point
keeping these special cases around for now reason.
- Get rid of hand-rolled `die` function and just use `AC_MSG_ERROR`.
- Abstract check + flag override for unregisterised and tables next to
code.
Oh, and as part of the above I also renamed/combined some variables
where it felt appropriate.
- GccIsClang -> CcLlvmBackend. This is for `AC_SUBST`, like the other
Camal case ones. It was never about gcc-llvm, or Apple's renamed clang,
to be clear.
- llvm_CC_FLAVOR -> CC_LLVM_BACKEND. This is for `AC_DEFINE`, like the
other all-caps snake case ones. llvm_CC_FLAVOR was just silly
indirection *and* an odd name to boot.
|
| |
|
|
| |
Fixes #17286.
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
Simon realised that the simple language composed of let bindings, bang
patterns and flat constructor patterns is enough to capture the
semantics of the source pattern language that are important for
pattern-match checking. Well, given that the Oracle is smart enough to
connect the dots in this less informationally dense form, which it is
now.
So we transform `translatePat` to return a list of `PmGrd`s relative to
an incoming match variable. `pmCheck` then trivially translates each of
the `PmGrd`s into constraints that the oracle understands.
Since we pass in the match variable, we incidentally fix #15884
(coverage checks for view patterns) through an interaction with !1746.
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
If you derive an instance like this:
```hs
deriving <...> instance Foo C
```
And the data constructors for `C` aren't in scope, then
`doDerivInstErrorChecks1` throws an error. Moreover, it will
_only_ throw an error if `<...>` is either `stock` or `newtype`.
This is because the code that the `anyclass` or `via` strategies
would generate would not require the use of the data constructors
for `C`.
However, `doDerivInstErrorChecks1` has another purpose. If you
write this:
```hs
import M (C(MkC1, ..., MkCn))
deriving <...> instance Foo C
```
Then `doDerivInstErrorChecks1` will call `addUsedDataCons` on
`MkC1` through `MkCn` to ensure that `-Wunused-imports` does not
complain about them. However, `doDerivInstErrorChecks1` was doing
this for _every_ deriving strategy, which mean that if `<...>` were
`anyclass` or `via`, then the warning about `MkC1` through `MkCn`
being unused would be suppressed!
The fix is simple enough: only call `addUsedDataCons` when the
strategy is `stock` or `newtype`, just like the other code paths
in `doDerivInstErrorChecks1`.
Fixes #17324.
|
| | |
|
