Commit Graph

461 Commits

Author SHA1 Message Date
Robert Widmann
980fde2ede Lift requirementsNotSatisfiedBy Into GenericSignature 2021-09-20 15:29:51 -07:00
Becca Royal-Gordon
c517b45bb4 Merge pull request #38948 from beccadax/the-copypasta-is-stale
[NFC] Factor out ASTContext `operator new`s
2021-08-20 11:04:56 -07:00
Becca Royal-Gordon
59bb325e4b [NFC] Factor out ASTContext operator news
Many, many, many types in the Swift compiler are intended to only be allocated in the ASTContext. We have previously implemented this by writing several `operator new` and `operator delete` implementations into these types. Factor those out into a new base class instead.
2021-08-19 11:19:52 -07:00
Doug Gregor
d54abea922 Implement customizable Sendable conformance diagnostics.
Rework Sendable checking to be completely based on "missing"
conformances, so that we can individually diagnose missing Sendable
conformances based on both the module in which the conformance check
happened as well as where the type was declared. The basic rules here
are to only diagnose if either the module where the non-Sendable type
was declared or the module where it was checked was compiled with a
mode that consistently diagnoses `Sendable`, either by virtue of
being Swift 6 or because `-warn-concurrency` was provided on the
command line. And have that diagnostic be an error in Swift 6 or
warning in Swift 5.x.

There is much tuning to be done here.
2021-08-14 08:13:10 -07:00
Robert Widmann
d75b34be22 Merge pull request #38753 from CodaFi/modulo-modules
[NFC] Remove Unused Module Parameter to Conformance Lookup
2021-08-11 10:36:39 -07:00
Robert Widmann
808220510e [NFC] Remove Unused Module Parameter to Conformance Lookup
It's been quite a long time since this unused parameter was introduced.
The intent is to produce the module as a root for the search - that is,
computing the set of conformances visible from that module, not the set
of conformances inside of that module. Callers have since been providing
all manner of module-scoped contexts to it.

Let's just get rid of it. When we want to teach protocol conformance
lookup to do this, we can revert this commit as a starting point and try
again.
2021-08-04 14:43:31 -07:00
Doug Gregor
f9c34756ef Parameterize conformance lookup on whether "missing" conformances are allowed.
Many clients of the conformance lookup operations would prefer to get
an invalid conformance (== there is no conformance) rather than a
missing conformance. Parameterize the conformance lookup operations so
that most callers won't see missing conformances, by filtering them
out at the end. Opt-in those callers that do want to see missing
conformances so they can be diagnosed.
2021-08-03 00:10:45 -07:00
Doug Gregor
de44396bd2 Always enable "missing" conformances to Sendable.
Always build the conformances, and produce warnings/errors when they are
needed during type checking.
2021-08-02 16:17:00 -07:00
Doug Gregor
c79fa23339 Implicitly build "missing" conformances to Sendable.
When looking up a conformance to Sendable fails, implicitly create a
"missing" builtin conformance. Such conformances allow type checking
to continue even in the presence of Sendable-related problems.

Diagnose these missing conformances when they are used in an actual
program, as part of availability checking for conformances and when we
are determining Sendability. This allows us to decide between an
error, a warning, and suppressing the diagnostic entirely without
affecting how the program is compiled. This is a step toward enabling
selective enforcement of Sendable.

Part of rdar://78269348.
2021-08-02 16:16:59 -07:00
Doug Gregor
3253a4fc1c [SE-0302] Implement structural conformances to Sendable.
Add implement conformance of structural types to Sendable as appropriate:
* A tuple type is Sendable when its element types are Sendable
* A metatype type is Sendable
* A function type is Sendable if it is @Sendable, thin, or C
* A builtin type is always Sendable

Implements rdar://76836578.
2021-07-28 07:38:55 -07:00
Doug Gregor
ecd830e342 Rework BuiltinProtocolConformance to be more like NormalProtocolConformance.
Give BuiltinProtocolConformance a generic signature, which can be used to
describe the generic parameters used within the builtin conformance, e.g.,
`<T1, T2, T3>` for a tuple type `(T1, T2, T3)`. Also store the
conditional requirements as trailing objects, requiring them to be
precomputed by whatever builds the conformances. Together, this means
that builtin protocol conformances act like normal conformances with
respect to conditional requirements and substitutions: they will be
defined generically, then a specialized conformance will be layered on
top to provide the substitutions.
2021-07-27 23:49:27 -07:00
Azoy
20cc067844 [AST] Introduce BuiltinProtocolConformance 2021-07-27 23:49:27 -07:00
Robert Widmann
a0615e9848 [NFC] Use GenericSIgnature::getGanonicalSignature Where Possible 2021-07-22 23:27:06 -07:00
Doug Gregor
06bbc70b3e Module printing and serialization support for @unchecked Sendable 2021-07-11 12:29:54 -07:00
Konrad `ktoso` Malawski
eada7df0e4 Ban classes from extending Actor and DistributedActor protocol explicitly (#38050)
* [Concurrency,Distributed] ban inheriting Actor and DistActor explicitly by class

* [Distributed] AnyActor can be a marker protocol
2021-06-25 06:06:35 +09:00
Doug Gregor
8a068e0c08 [SE-0316] Introduce the GlobalActor protocol to describe global actors.
Based on the discussion in the first review of the global actors
proposal, introduce a `GlobalActor` protocol that describes types that
can be global actors. Introduce this protocol, make `@globalActor`
types implicitly conform to it, and remove all of the bespoke
validation logic that was used to check the "shared" member.

Addresses rdar://79339591
2021-06-15 06:39:12 -07:00
Konrad `ktoso` Malawski
6008b32789 [Distributed] initial distributed support, fixed availability (#37650)
* [Distributed] Initial distributed checking

* [Distributed] initial types shapes and conform to DistributedActor

* [Distributed] Require Codable params and return types

* [Distributed] initial synthesis of fields and constructors

* [Distributed] Field and initializer synthesis

* [Distributed] Codable requirement on distributed funcs; also handle <T: Codable>

* [Distributed] handle generic type params which are Codable in dist func

[Distributed] conformsToProtocol after all

* [Distributed] Implement remote flag on actors

* Implement remote flag on actors

* add test

* actor initializer that sets remote flag

[Distributed] conformances getting there

* [Distributed] dont require async throws; cleanup compile tests

* [Distributed] do not synthesize default implicit init, only our special ones

* [Distributed] properly synth inits and properties; mark actorTransport as _distributedActorIndependent

Also:

- do not synthesize default init() initializer for dist actor

* [Distributed] init(transport:) designated and typechecking

* [Distributed] dist actor initializers MUST delegate to local-init

* [Distributed] check if any ctors in delegation call init(transport:)

* [Distributed] check init(transport:) delegation through many inits; ban invoking init(resolve:using:) explicitly

* [Distributed] disable IRGen test for now

* [Distributed] Rebase cleanups

* [Concurrent] transport and address are concurrent value

* [Distributed] introduce -enable-experimental-distributed flag

* rebase adjustments again

* rebase again...

* [Distributed] distributed functions are implicitly async+throws outside the actor

* [Distributed] implicitly throwing and async distributed funcs

* remove printlns

* add more checks to implicit function test

* [Distributed] resolve initializer now marks the isRemote actor flag

* [Distributed] distributedActor_destroy invoked instead, rather than before normal

* [Distributed] Generate distributed thunk for actors

* [distributed] typechecking for _remote_ functions existing, add tests for remote funcs

* adding one XFAIL'ed task & actor lifetime test

The `executor_deinit1` test fails 100% of the time
(from what I've seen) so I thought we could track
and see when/if someone happens to fix this bug.

Also, added extra coverage for #36298 via `executor_deinit2`

* Fix a memory issue with actors in the runtime system, by @phausler

* add new test that now passes because of patch by @phausler

See previous commit in this PR.
Test is based on one from rdar://74281361

* fix all tests that require the _remote_ function stubs

* Do not infer @actorIndependent onto `let` decls

* REVERT_ME: remove some tests that hacky workarounds will fail

* another flaky test, help build toolchain

* [Distributed] experimental distributed implies experimental concurrency

* [Distributed] Allow distributed function that are not marked async or throws

* [Distributed] make attrs SIMPLE to get serialization generated

* [Distributed] ActorAddress must be Hashable

* [Distributed] Implement transport.actorReady call in local init

* cleanup after rebase

* [Distributed] add availability attributes to all distributed actor code

* cleanup - this fixed some things

* fixing up

* fixing up

* [Distributed] introduce new Distributed module

* [Distributed] diagnose when missing 'import _Distributed'

* [Distributed] make all tests import the module

* more docs on address

* [Distributed] fixup merge issues

* cleanup: remove unnecessary code for now SIMPLE attribute

* fix: fix getActorIsolationOfContext

* [Distributed] cmake: depend on _concurrency module

* fixing tests...

* Revert "another flaky test, help build toolchain"

This reverts commit 83ae6654dd.

* remove xfail

* clenup some IR and SIL tests

* cleanup

* [Distributed] fix cmake test and ScanDependencies/can_import_with_map.swift

* [Distributed] fix flags/build tests

* cleanup: use isDistributed wherever possible

* [Distributed] don't import Dispatch in tests

* dont link distributed in stdlib unittest

* trying always append distributed module

* cleanups

* [Distributed] move all tests to Distributed/ directory

* [lit] try to fix lit test discovery

* [Distributed] update tests after diagnostics for implicit async changed

* [Distributed] Disable remote func tests on Windows for now

* Review cleanups

* [Distributed] fix typo, fixes Concurrency/actor_isolation_objc.swift

* [Distributed] attributes are DistributedOnly (only)

* cleanup

* [Distributed] cleanup: rely on DistributedOnly for guarding the keyword

* Update include/swift/AST/ActorIsolation.h

Co-authored-by: Doug Gregor <dgregor@apple.com>

* introduce isAnyThunk, minor cleanup

* wip

* [Distributed] move some type checking to TypeCheckDistributed.cpp

* [TypeCheckAttr] remove extra debug info

* [Distributed/AutoDiff] fix SILDeclRef creation which caused AutoDiff issue

* cleanups

* [lit] remove json import from lit test suite, not needed after all

* [Distributed] distributed functions only in DistributedActor protocols

* [Distributed] fix flag overlap & build setting

* [Distributed] Simplify noteIsolatedActorMember to not take bool distributed param

* [Distributed] make __isRemote not public

* [Distributed] Fix availability and remove actor class tests

* [actorIndependent] do not apply actorIndependent implicitly to values where it would be illegal to apply

* [Distributed] disable tests until issue fixed

Co-authored-by: Dario Rexin <drexin@apple.com>
Co-authored-by: Kavon Farvardin <kfarvardin@apple.com>
Co-authored-by: Doug Gregor <dgregor@apple.com>
2021-05-28 07:22:03 +09:00
Konrad `ktoso` Malawski
0c75bd2a39 Revert Initial distributed, some issues to be fixed first (#37556)
* Revert "[Distributed] disable tests until issue fixed"

This reverts commit 0a04278920.

* Revert "[Distributed] Initial `distributed` actors and functions and new module (#37109)"

This reverts commit 814ede0cf3.
2021-05-21 19:28:48 +09:00
Konrad `ktoso` Malawski
814ede0cf3 [Distributed] Initial distributed actors and functions and new module (#37109)
* [Distributed] Initial distributed checking

* [Distributed] initial types shapes and conform to DistributedActor

* [Distributed] Require Codable params and return types

* [Distributed] initial synthesis of fields and constructors

* [Distributed] Field and initializer synthesis

* [Distributed] Codable requirement on distributed funcs; also handle <T: Codable>

* [Distributed] handle generic type params which are Codable in dist func

[Distributed] conformsToProtocol after all

* [Distributed] Implement remote flag on actors

* Implement remote flag on actors

* add test

* actor initializer that sets remote flag

[Distributed] conformances getting there

* [Distributed] dont require async throws; cleanup compile tests

* [Distributed] do not synthesize default implicit init, only our special ones

* [Distributed] properly synth inits and properties; mark actorTransport as _distributedActorIndependent

Also:

- do not synthesize default init() initializer for dist actor

* [Distributed] init(transport:) designated and typechecking

* [Distributed] dist actor initializers MUST delegate to local-init

* [Distributed] check if any ctors in delegation call init(transport:)

* [Distributed] check init(transport:) delegation through many inits; ban invoking init(resolve:using:) explicitly

* [Distributed] disable IRGen test for now

* [Distributed] Rebase cleanups

* [Concurrent] transport and address are concurrent value

* [Distributed] introduce -enable-experimental-distributed flag

* rebase adjustments again

* rebase again...

* [Distributed] distributed functions are implicitly async+throws outside the actor

* [Distributed] implicitly throwing and async distributed funcs

* remove printlns

* add more checks to implicit function test

* [Distributed] resolve initializer now marks the isRemote actor flag

* [Distributed] distributedActor_destroy invoked instead, rather than before normal

* [Distributed] Generate distributed thunk for actors

* [distributed] typechecking for _remote_ functions existing, add tests for remote funcs

* adding one XFAIL'ed task & actor lifetime test

The `executor_deinit1` test fails 100% of the time
(from what I've seen) so I thought we could track
and see when/if someone happens to fix this bug.

Also, added extra coverage for #36298 via `executor_deinit2`

* Fix a memory issue with actors in the runtime system, by @phausler

* add new test that now passes because of patch by @phausler

See previous commit in this PR.
Test is based on one from rdar://74281361

* fix all tests that require the _remote_ function stubs

* Do not infer @actorIndependent onto `let` decls

* REVERT_ME: remove some tests that hacky workarounds will fail

* another flaky test, help build toolchain

* [Distributed] experimental distributed implies experimental concurrency

* [Distributed] Allow distributed function that are not marked async or throws

* [Distributed] make attrs SIMPLE to get serialization generated

* [Distributed] ActorAddress must be Hashable

* [Distributed] Implement transport.actorReady call in local init

* cleanup after rebase

* [Distributed] add availability attributes to all distributed actor code

* cleanup - this fixed some things

* fixing up

* fixing up

* [Distributed] introduce new Distributed module

* [Distributed] diagnose when missing 'import _Distributed'

* [Distributed] make all tests import the module

* more docs on address

* [Distributed] fixup merge issues

* cleanup: remove unnecessary code for now SIMPLE attribute

* fix: fix getActorIsolationOfContext

* [Distributed] cmake: depend on _concurrency module

* fixing tests...

* Revert "another flaky test, help build toolchain"

This reverts commit 83ae6654dd.

* remove xfail

* clenup some IR and SIL tests

* cleanup

* [Distributed] fix cmake test and ScanDependencies/can_import_with_map.swift

* [Distributed] fix flags/build tests

* cleanup: use isDistributed wherever possible

* [Distributed] don't import Dispatch in tests

* dont link distributed in stdlib unittest

* trying always append distributed module

* cleanups

* [Distributed] move all tests to Distributed/ directory

* [lit] try to fix lit test discovery

* [Distributed] update tests after diagnostics for implicit async changed

* [Distributed] Disable remote func tests on Windows for now

* Review cleanups

* [Distributed] fix typo, fixes Concurrency/actor_isolation_objc.swift

* [Distributed] attributes are DistributedOnly (only)

* cleanup

* [Distributed] cleanup: rely on DistributedOnly for guarding the keyword

* Update include/swift/AST/ActorIsolation.h

Co-authored-by: Doug Gregor <dgregor@apple.com>

* introduce isAnyThunk, minor cleanup

* wip

* [Distributed] move some type checking to TypeCheckDistributed.cpp

* [TypeCheckAttr] remove extra debug info

* [Distributed/AutoDiff] fix SILDeclRef creation which caused AutoDiff issue

* cleanups

* [lit] remove json import from lit test suite, not needed after all

* [Distributed] distributed functions only in DistributedActor protocols

* [Distributed] fix flag overlap & build setting

* [Distributed] Simplify noteIsolatedActorMember to not take bool distributed param

* [Distributed] make __isRemote not public

Co-authored-by: Dario Rexin <drexin@apple.com>
Co-authored-by: Kavon Farvardin <kfarvardin@apple.com>
Co-authored-by: Doug Gregor <dgregor@apple.com>
2021-05-21 09:12:29 +09:00
Robert Widmann
b452919869 Merge pull request #36509 from CodaFi/con-tutta-formance
Redo getConditionalRequirements as a Request
2021-03-19 10:08:53 -07:00
Robert Widmann
ee5f2c3131 Redo getConditionalRequirements as a Request 2021-03-18 23:28:52 -07:00
Doug Gregor
9579390024 [SE-0304] Rename ConcurrentValue to Sendable 2021-03-18 22:48:20 -07:00
Doug Gregor
b5e4b085aa Infer ConcurrentValue conformances for structs and enums.
When a struct or enum has only ConcurrentValue-conforming instance
data, infer conformance to ConcurrentValue.
2021-03-02 00:23:33 -08:00
Doug Gregor
114f856537 Reimplement IterableDeclContext::getLocalProtocls() using getLocalConformances()
The uncached, rarely-used getLocalProtocols() does not benefit from
having its own distinct implementation. Reimplement it on top of
getLocalConformances() to simplify things and benefit from the
request-evaluator infrastructure.
2021-03-01 22:05:24 -08:00
Doug Gregor
01d4440fb9 Funnel all "get local conformances" queries through a request.
LookupAllConformancesInContextRequest caches the results of performing
lookup of all of the conformances ascribed to a given iterable
declaration context. However, it was only used in a small number of
places, with most clients using a different API
(`getLocalConformances()`) that does not provide
caching, cycle detection, or dependency tracking.

Sink LookupAllConformancesInContextRequest lower in the stack, and
reimplement `getLocalConformances()` on top of it. This ensures that
all of the various queries go through the cached request and get the
benefits of the request-evaluator infrastructure.
2021-03-01 22:05:24 -08:00
Slava Pestov
53e06d69b5 AST: Factor out a new Requirement::getProtocolDecl() utility method 2021-02-25 17:21:18 -05:00
Slava Pestov
07bd07926f AST: Implement extractNearestSourceLoc() for ProtocolConformance 2021-02-10 16:30:30 -05:00
Slava Pestov
a1d483faf3 AST: Move some code from ProtocolConformance.cpp to Effects.cpp / TypeCheckEffects.cpp 2021-02-09 00:11:01 -05:00
Philippe Hausler
6e05240426 AsyncSequence and protocol conformance rethrows (#35224)
* Initial draft of async sequences

* Adjust AsyncSequence associated type requirements

* Add a draft implementation of AsyncSequence and associated functionality

* Correct merge damage and rename from GeneratorProtocol to AsyncIteratorProtocol

* Add AsyncSequence types to the cmake lists

* Add cancellation support

* [DRAFT] Implementation of protocol conformance rethrowing

* Account for ASTVerifier passes to ensure throwing and by conformance rethrowing verifies appropriately

* Remove commented out code

* OtherConstructorDeclRefExpr can also be a source of a rethrowing kind function

* Re-order the checkApply logic to account for existing throwing calculations better

* Extract rethrowing calculation into smaller functions

* Allow for closures and protocol conformances to contribute to throwing

* Add unit tests for conformance based rethrowing

* Restrict rethrowing requirements to only protocols marked with @rethrows

* Correct logic for gating of `@rethrows` and adjust the determinates to be based upon throws and not rethrows spelling

* Attempt to unify the async sequence features together

* Reorder try await to latest syntax

* revert back to the inout diagnosis

* House mutations in local scope

* Revert "House mutations in local scope"

This reverts commit d91f1b25b59fff8e4be107c808895ff3f293b394.

* Adjust for inout diagnostics and fall back to original mutation strategy

* Convert async flag to source locations and add initial try support to for await in syntax

* Fix case typo of MinMax.swift

* Adjust rethrowing tests to account for changes associated with @rethrows

* Allow parsing and diagnostics associated with try applied to for await in syntax

* Correct the code-completion for @rethrows

* Additional corrections for the code-completion for @rethrows this time for the last in the list

* Handle throwing cases of iteration of async sequences

* restore building XCTest

* First wave of feedback fixes

* Rework constraints checking for async sequence for-try-await-in checking

* Allow testing of for-await-in parsing and silgen testing and add unit tests for both

* Remove async sequence operators for now

* Back out cancellation of AsyncIteratorProtocols

* Restructure protocol conformance throws checking and cache results

* remove some stray whitespaces

* Correct some merge damage

* Ensure the throwing determinate for applying for-await-in always has a valid value and adjust the for-await-in silgen test to reflect the cancel changes

* Squelch the python linter for line length
2021-01-25 18:48:50 -08:00
Alejandro Alonso
424802fb34 Revert SE-0283 (#34492)
Reverted despite build failures.
2020-10-29 17:32:06 -07:00
Azoy
48ea83723e Manually define _rawHashValue in compatibility libraries, AST fixes for builtin protocol conformance
Remember to use substituted type in builtin conformance substitution
2020-10-22 18:28:38 -04:00
Azoy
f21a306ae5 [AST] Introduce BuiltinProtocolConformance 2020-10-22 18:24:27 -04:00
Doug Gregor
ab3c5dee3e [Concurrency] Introduce Actor protocol to which actor classes all conform.
Introduce a new Actor protocol, which is a class-bound protocol with only
one requirement:

    func enqueue(partialTask: PartialAsyncTask)

All actor classes implicitly conform to this protocol, and will synthesize
a (currently empty) definition of `enqueue(partialTask:)` unless a suitable
one is provided explicitly.
2020-09-28 16:59:21 -07:00
David Zarzycki
1e940c2c7e [NFC] Fix -Wsuggest-override warnings
LLVM, as of 77e0e9e17daf0865620abcd41f692ab0642367c4, now builds with
-Wsuggest-override. Let's clean up the swift sources rather than disable
the warning locally.
2020-08-13 16:17:46 -04:00
Anthony Latsis
55447e66aa Merge pull request #31645 from AnthonyLatsis/relocate-to-iterabledc
[NFC] AST: Relocate some conformance lookup client methods from DeclContext to IterableDeclContext
2020-05-18 22:25:08 +03:00
Arnold Schwaighofer
b40b1be41d Existentials don't always conform to a protocol via an abstract conformance
So it is not always correct to use the current conformance when substituting.

rdar://62894495
2020-05-12 12:20:01 -07:00
Anthony Latsis
bfe25fabeb [NFC] AST: Relocate getLocalConformances to IterableDeclContext 2020-05-08 17:43:09 +03:00
Anthony Latsis
b3af1a03f1 [NFC] AST: Relocate takeConformanceDiagnostics & getLocalProtocols to IterableDeclContext 2020-05-08 03:15:15 +03:00
Arnold Schwaighofer
b5f5495e98 SILCombine: Fix update of substitution map when substituting opened opaque archetypes
When performing the substitution of the 'concrete' type that happens to
be an opened archetype we need to force the substitution to actually
call the conformance remapping function.

rdar://62202282
SR-12571
2020-04-27 14:52:39 -07:00
Anthony Latsis
b8341687fa AST: Fast path for matching can. signatures in requirementsNotSatisfiedBy 2020-04-23 03:18:37 +03:00
Robert Widmann
4de729fffc [NFC] Add LookupConformancesInContextRequest
Add a request to lookup all implied conformances for use while
typechecking the primary. This provides a cache-point for
evaluator-based dependency tracking.
2020-03-26 10:26:25 -07:00
Robert Widmann
a9e11e3130 [NFC] Separate Taking Redundant Conformance Diagnostics From The Lookup Table 2020-03-24 12:40:11 -07:00
Dan Zheng
1486d6b346 NFC: Add GenericSignature::getCanonicalSignature. (#29105)
Motivation: `GenericSignatureImpl::getCanonicalSignature` crashes for
`GenericSignature` with underlying `nullptr`. This led to verbose workarounds
when computing `CanGenericSignature` from `GenericSignature`.

Solution: `GenericSignature::getCanonicalSignature` is a wrapper around
`GenericSignatureImpl::getCanonicalSignature` that returns the canonical
signature, or `nullptr` if the underlying pointer is `nullptr`.

Rewrite all verbose workarounds using `GenericSignature::getCanonicalSignature`.
2020-01-12 12:17:41 -08:00
Saleem Abdulrasool
5e4017019b AST: remove invalid static_assert
This removes a set of static assertions that did not do what they were
supposed to do.

The static assertions were attempting to ensure that the functions are
different.  However, the address of a function is *not* a constant
expression and cannot be used in a static assertion.

Furthermore, the static assert is either tautologically true or will be
caught as a compile error on the dispatch.    The methods being checked
here are non-virtual.  The PFN that was being computed is tautologically
different as there is no virtuality and the two methods must be
different (barring any ICF coalescing that may be performed by the
linker or by LTO).  The method must exist, otherwise, the dispatch
itself will trigger a resolution failure.

Effectively, the static assertionss did not compute anything as a
result:
- the method's existence is checked by the dispatch
- the address of the function is always different

This was identified by building with GCC 7.
2019-12-26 16:53:46 -08:00
Robert Widmann
01d272073a Requestify Witness Resolution
Witness matching is a source of a lot of ad-hoc cycles, and mixes the
logic that performs resolution, caching, validation, and cycle detection into one
place.  To make matters worse, some checkers kick off other checks in
order to cache work for further declarations, and access an internal
cache on their subject conformance for many requirements at once, or
sometimes just one requirement.

None of this fits into the request evaluator's central view of the
caching.  This is further evidenced by the fact that if you attempt to
move the caching step into the evaluator, it overcaches the same
witness and trips asserts.

As a start, define requests for the resolution steps, and flush some
hacks around forcing witness resolution. The caching logic is mostly
untouched (the requests don't actually cache anything), but some cycle
breaking is now handled in the evaluator itself.  Once witness matching
has been refactored to cache with the evaluator, all of these hacks can
go away.

My urge to destroy the LazyResolver outweighs the compromises here.
2019-11-05 13:28:07 -08:00
Robert Widmann
b849e51768 Use operator bool to claw back some readability 2019-10-29 16:56:21 -07:00
Robert Widmann
3e1a61f425 [NFC] Fold The Tri-State In Optional<ProtocolConformanceRef>
ProtocolConformanceRef already has an invalid state.  Drop all of the
uses of Optional<ProtocolConformanceRef> and just use
ProtocolConformanceRef::forInvalid() to represent it.  Mechanically
translate all of the callers and callsites to use this new
representation.
2019-10-29 16:55:56 -07:00
Robert Widmann
5a8d0744c3 [NFC] Adopt TypeBase-isms for GenericSignature
Structurally prevent a number of common anti-patterns involving generic
signatures by separating the interface into GenericSignature and the
implementation into GenericSignatureBase.  In particular, this allows
the comparison operators to be deleted which forces callers to
canonicalize the signature or ask to compare pointers explicitly.
2019-09-30 14:04:36 -07:00
Robert Widmann
e7fccde40c Directly detect the cyclic case while computing conditional requirement
The general class of cycle here is when validation asks for the generic signature which triggers requirement checking which forces us to ask for the generic signature of the extension again.  We should look into a more principled solution.

See rdar://55263708
2019-09-20 20:38:38 -07:00
Slava Pestov
542d255b32 AST: ProtocolConformanceRef::subst() returns an invalid conformance instead of trapping
This is for consistency with Type::subst() which returns ErrorTypes.
2019-09-20 17:59:56 -04:00