The inactive list may contain other disjunctions associated with bound
type variables. For now, make sure we recover the orphan directly to
fix the crash in SR-4056 / rdar://problem/30686926. Later, we can
treat these as orphans, too.
This is disabled by default but enabled under the frontend option
-propagate-constraints.
The idea here is to have a pass that enforces local consistency in our
constraint system, in order to reduce the domains of constraint
variables, speeding up the solving of the constraint system.
The initial focus will be on reducing the size of the disjunctions for
function overloads with the hope that it substantially improves the
performance of type checking many expressions.
When this was migrated over to the awesome new special representation
of type(of:) the argument coercion didn’t come with it. The missing
load expression caused any l-value run through type(of:) to crash in the
verifier.
Get ready to handle lookup of generic parameters into a DeclContext
that is a SubscriptDecl. No functional change yet, this this code
path is not reachable.
The constraint graph models type variables (as the nodes) and
constraints (as the multi-edges connecting nodes). The connected
components within this (multi-)graph are independent subproblems that
are solved separately; the results from each subproblem are then
combined. The approach helps curtail exponential behavior, because
(e.g.) the disjunctions/type variables in one component won't ever be
explored while solving for another component
This approach assumes that all of the constraints that cannot be
immediately solved are associated with one or more type
variables. This is almost entirely true---constraints that don't
involve type variables are immediately simplified.
Except for disjunctions. A disjunction involving no type variables
would not appear *at all* in the constraint graph. Worse, it's
independence from other constraints could not be established, so the
constraint solver would go exponential for every one of these
constraints. This has always been an issue, but it got worse with the
separation of type checking of "as" into the "coercion" case and the
"bridging" case, which introduced more of these disjunctions. This led
to counterintuitive behavior where adding "as Foo" would cause the
type checking to take *more* time than leaving it off, if both sides
of the "as" were known to be concrete. rdar://problem/30545483
captures a case (now in the new test case) where we saw such
exponential blow-ups.
Teach the constraint graph to keep track of "orphaned" constraints
that don't reference any type variables, and treat each "orphaned"
constraint as a separate connected component. That way, they're solved
independently.
Fixes rdar://problem/30545483 and will likely curtain other
exponential behavior we're seeing in the solver.
The list of directly inherited protocols of a ProtocolDecl is already
encoded in the requirement signature, as conformance constraints where
the subject is Self. Gather the list from there rather than separately
computing/storing the list of "inherited protocols".
The root cause is that NormalProtocolConformance::forEachValueWitness()
needs to skip protocol members that are not requirements.
Otherwise we end up passing such a non-requirement member down to
NormalProtocolConformance::getWitness() and hit an assert when we
cannot find it.
It looks like this code path was only ever hit from SourceKit.
The fix moves TypeChecker::isRequirement() to a method on ValueDecl,
and calls it in the right places.
Fixes <https://bugs.swift.org/browse/SR-3815>.
When trying to solve for the test case we attempt to simplify a value
member constraint and it fails because we've bound the LHS type
variable to an optional as a result of other constraints involving
other type variables in the equivalence class of this type
variable.
We don't have enough information to directly deduce the non-optional
type directly from other constraints involving this type variable.
This change results in one interesting type checking anomoly. In Swift
3 mode, we now successfully typecheck an expression that we previously
did not. Although the type checking technically makes sense given the
type checking rules we have in place, it can be a bit surprising to
users. Fortunately we emit a warning that calls out the surprising
behavior of considering an expression unused.
Fixes rdar://problem/30271695.
This was necessary when we would 'adopt' archetypes from outer
contexts, but that is long gone, and the only thing it accomplished
was emitting duplicate diagnostics.
Reimplement the RequirementSource class, which captures how
a particular requirement is satisfied by a generic signature. The
primary goal of this rework is to keep the complete path one follows
in a generic signature to get from some explicit requirement in the
generic signature to some derived requirement or type, e.g.,
1) Start at an explicit requirement "C: Collection"
2) Go to the inherited protocol Sequence,
3) Get the "Iterator" associated type
4) Get its conformance to "IteratorProtocol"
5) Get the "Element" associated type
We don't currently capture all of the information we want in the path,
but the basic structure is there, and should also allow us to capture
more source-location information, find the "optimal" path, etc. There are
are a number of potential uses:
* IRGen could eventually use this to dig out the witness tables and
type metadata it needs, instead of using its own fulfillment
strategy
* SubstitutionMap could use this to lookup conformances, rather than
it's egregious hacks
* The canonical generic signature builder could use this to lookup
conformances as needed, e.g., for the recursive-conformances case.
... and probably more simplifications, once we get this right.
Add an option to the lexer to go back and get a list of "full"
tokens, which include their leading and trailing trivia, which
we can index into from SourceLocs in the current AST.
This starts the Syntax sublibrary, which will support structured
editing APIs. Some skeleton support and basic implementations are
in place for types and generics in the grammar. Yes, it's slightly
redundant with what we have right now. lib/AST conflates syntax
and semantics in the same place(s); this is a first step in changing
that to separate the two concepts for clarity and also to get closer
to incremental parsing and type-checking. The goal is to eventually
extract all of the syntactic information from lib/AST and change that
to be more of a semantic/symbolic model.
Stub out a Semantics manager. This ought to eventually be used as a hub
for encapsulating lazily computed semantic information for syntax nodes.
For the time being, it can serve as a temporary place for mapping from
Syntax nodes to semantically full lib/AST nodes.
This is still in a molten state - don't get too close, wear appropriate
proximity suits, etc.
If a conforming type provided explicit witnesses for some of its associated types and inferred others, we would still harvest inference solutions from methods that contradict the explicit witnesses, leading to bogus ambiguity errors in some situations. Fix this by skipping inference candidates that contradict explicit type witnesses. Fixes SR-3979.
If a convenience initializer in a subclass delegated to an inherited initializer from its base, we would end up type-checking the reference to the base class constructor as returning the base type, leading to type mismatches in the result AST and downstream crashes. We can wrap up the synthesized OtherConstructorRefExpr in a CovariantFunctionConversionExpr, which will trick the type checker into propagating the covariant result that gets rebound to `self` on return, avoiding this problem. (For now, I'm avoiding making the constructor decl formally have a Self return type, since that exposes a bunch of downstream breakage in code paths that only expect FuncDecls to be covariant, and also affects the mangling of constructors, causing a bunch of test case thrash we really don't want to inflict on the 3.1 branch.)
This function was returning an ArrayRef pointing into a data structure
that is easily mutated via code walking over that ArrayRef, which
could cause spooky side effects, particularly during
deserialization. Perform a defensive copy to eliminate such side
effects.
These changes caused a number of issues:
1. No debug info is emitted when a release-debug info compiler is built.
2. OS X deployment target specification is broken.
3. Swift options were broken without any attempt any recreating that
functionality. The specific option in question is --force-optimized-typechecker.
Such refactorings should be done in a fashion that does not break existing
users and use cases.
This reverts commit e6ce2ff388.
This reverts commit e8645f3750.
This reverts commit 89b038ea7e.
This reverts commit 497cac64d9.
This reverts commit 953ad094da.
This reverts commit e096d1c033.
rdar://30549345
In 74d979f0ac, the policy was changed
so that only value type accessors are ever marked transparent, and
not class accessors.
This was intended to fix a bug where inlining an accessor of an
Objective-C-derived class across module boundaries caused a linker
failure because the accessor referenced a field offset variable,
which has hidden visibility.
However, this also caused a performance regression for Swift native
classes. Bring back the old behavior for Swift native classes in
non-resilient modules.
Fixes <rdar://problem/29884727>.
After we call into typeCheckExpression() we need to cache the
resulting types in the constraint system type map because we later
call into code that reads the types out of the type map.
Fixes rdar://problem/30376186 as well as a couple crashers.
- Don't allow @_inlineable on stored properties; this generates
invalid SIL since clients can't know about stored properties of
resilient types. Accessors for stored properties of non-resilient
types are already @_inlineable anyway.
- Don't allow @_inlineable on declarations that are not public or
@_versioned, since it's simply redundant.
This patch splits add_swift_library into two functions one which handles
the simple case of adding a library that is part of the compiler being
built and the second handling the more complicated case of "target"
libraries, which may need to build for one or more targets.
The new add_swift_library is built using llvm_add_library, which re-uses
LLVM's CMake modules. In adapting to use LLVM's modules some of
add_swift_library's named parameters have been removed and
LINK_LIBRARIES has changed to LINK_LIBS, and LLVM_LINK_COMPONENTS
changed to LINK_COMPONENTS.
This patch also cleans up libswiftBasic's handling of UUID library and
headers, and how it interfaces with gyb sources.
add_swift_library also no longer has the FILE_DEPENDS parameter, which
doesn't matter because llvm_add_library's DEPENDS parameter has the same
behavior.
@objc inference was looking at unavailable requirements---for which we
don't ever record witnesses---at a point when it is no longer possible
to record such a witness. This is a targeted fix; we need to tackle
the issue of unavailable and optional requirements more thoroughly.
Fixes SR-3917 / rdar://problem/30474860.
