This patch adds the beginning of building the type refinement context tree for
availability checking in Sema, guarded by by the
-enable-experimental-availability-checking option. This tree parallels the AST
but is much more sparse: we introduce a new TypeRefinementContext only when
needed. Each context refines the range of potential OS versions that could be
encountered at run time. For the moment, we only refine contexts for function
bodies. I will add refinement contexts for #os(...) in a later commit.
The AST is not directly connected to the TRC tree except at the SourceFile
level; when type checking, we use source locations to look up the TRC
corresponding to an AST element. For the moment, we emit a diagnostic when the
programmer references a potentially unavailable declaration. We will later
change this to treat the declaration as if it had optional type.
Swift SVN r22145
This commit adds a new expression (AvailabilityQueryExpr) and a single kind of
specification for when a block of code or function is available
(VersionConstraintAvailabilitySpec). We may add more kinds of specifications
in the future. At the moment, the AvailabilityQueryExpr allows only a
single platform to be queried; I will add support for multiple platforms
in a later commit.
This commit contains just the added AST nodes; no parsing, type checking, etc.
I’ve added assert(false && “Unimplemented”) for places where support for
AvailabilityQueryExpr will need to be added later.
Swift SVN r21760
Use it to replace the switch-based implementation of Type::findIf. This
will also be used for typealias recursive inheritance checking and for
swift2objc forward declarations.
Swift SVN r12599
Have ArchetypeBuilder key the archetypes it produces by the abstract {depth,index} position of generic parameters rather than by the identity of particular GenericTypeParamDecls. Tighten the signature of AbstractTypeParamDecl-taking methods to only take GenericTypeParamDecls; that's the only case that comes up anymore. Introduce 'addGenericParameter' and 'getArchetype' overloads that work with GenericTypeParamTypes and DependentMemberTypes in addition to those that work with GenericTypeParamDecls.
Move ArchetypeBuilder.cpp from 'Sema' to 'AST' to correspond to its header's location.
In this version of the patch, we handle the problem of invalid nested protocol decls by simply ignoring the parent generic context of ProtocolDecls in validateGenericTypeSignature, which allows for better recovery and avoids the crash problems with the ErrorType approach I tried in the previous patch.
Swift SVN r10983
Have ArchetypeBuilder key the archetypes it produces by the abstract {depth,index} position of generic parameters rather than by the identity of particular GenericTypeParamDecls. Tighten the signature of AbstractTypeParamDecl-taking methods to only take GenericTypeParamDecls; that's the only case that comes up anymore. Introduce 'addGenericParameter' and 'getArchetype' overloads that work with GenericTypeParamTypes and DependentMemberTypes in addition to those that work with GenericTypeParamDecls.
Move ArchetypeBuilder.cpp from 'Sema' to 'AST' to correspond to its header's location.
When we parse something like 'protocol P { protocol Q {} }', eagerly give the erroneous nested protocol Q an ErrorType to suppress type-checking of the declaration. Otherwise, the nested implicit 'Self' parameters, which are fixed depth 0 index 0 in the generic parameter space, will collide in the ArchetypeBuilder.
Swift SVN r10966
Previously, the Parser and BranchStmt typedef-ed ExprStmtOrDecl as a pointer union. Using typedef made the objects compatible, but did not allow us to extend the type with helper methods, such as getSourceRange(), which is something you can get on all of the AST objects. This patch introduces ASTNode that subclasses from PointerUnion and is used by both parser and BranchStmt.
Swift SVN r9971
UnqualifiedLookup to ask an external source for
names. There are two phases to this external lookup:
- Before consulting globals in other modules,
UnqualifiedLookup calls lookupOverrides() to see
if there are any results that should override the
results from modules. (N.b.: these should not be
able to override names that are locally defined.)
- After consulting globals in other modules,
UnqualifiedLookup as a last resort calls
lookupFallbacks() to see if there's anything out
there at all that could serve that name. This may
be more computationally expensive.
These hooks are used by LLDB's expression parser to
resolve names for persistent variables (akin to the
existing $0, $1, ... variables) and variables local
to the current frame.
Swift SVN r9014
The new ConcreteDeclRef class provides a possibly-speciaized reference
to a declaration, which allows DynamicMemberRefExpr to refer to both
generic and non-generic members. without having to split the AST node.
Swift SVN r7839
This makes lookupVisibleDecls use the same code path as qualified and
unqualified lookup. This is more expensive, because it needs to actually
collect a list of /all/ decls in order to properly compute shadowing
information, but this list is not likely to change once the set of imports
has been computed, so we can cache it.
Swift SVN r7168
Factor the ProtocolConformance class into a small hierarchy of
protocol conformances:
- "normal" conformance, which provides a complete mapping for the
explicit conformance of a nominal type (which may be generic) to a
protocol;
- "specialized" conformance, which specializes a generic
conformance by applying a set of substitutions; and
- "inherited" conformance, which projects the conformance from a
superclass to a conformance for a subclass.
In this scheme "normal" conformances are fairly heavyweight, because
they provide a complete mapping. Normal conformances are unique,
because they're associated with explicit conformance declarations
(which cannot be repeated within a module; checking is TBD). Thus, IR
generation will eventually emit them as strong symbols.
"Specialized" and "inherited" conformances occur when we're dealing
with generic specializations or subclasses. They project most of their
members through to some underlying conformance, eventually landing at
a "normal" conformance. ASTContext is responsible for uniquing these
conformances when it sees them. The IR generation model for
specialized conformances will involve runtime specialization of the
underlying witness table; inherited conformances are probably no-ops
from the IR generation perspective.
Aside from being the right thing to do, having small, uniqued
conformances for the specialization and inheritance cases is good for
compile-time performance and memory usage. We're not really taking
advantage of this everywhere we could, yet.
This change uncovered a few existing issues (one known, one not
known), particularly because we're projecting inherited conformances
rather than building new conformances:
- <rdar://problem/14620454>: protocol witnesses to methods of
classes need to perform dynamic dispatch. See the
test/Interpreter/typeof.swift test for an example.
- <rdar://problem/14637688>: comparing NSString and String with ==
fails, because they are inter-convertible. I suspect we were missing
some protocol conformances previously, and therefore accepting this
obviously-invalid code.
Swift SVN r6865
This the first part for improving source location fidelity for types,
changes to follow:
-The Parser will not create any types, it will just create TypeReprs.
-The type checker will create the types by going through TypeReprs.
-IdentifierType will be removed.
Swift SVN r6112
Implement a 'lookupVisibleDecls' API similar to Clang's that replicates the UnqualifiedLookup logic for walking through a given scope looking for decls. Use it to populate the completion list in the repl.
Still to be done: Clang module lookup via Clang's lookupVisibleDecls, and context deduction from dotted path expressions.
Swift SVN r4056
instead .
1,2d
1i
Change the 'walk' APIs to use virtual dispatch instead of
blocks. This makes it much easier to thread information
through the API, as well to extend the API to handle
recursive visiting of other structures (e.g., Decls
and Patterns).
Swift SVN r1101
actually render emitted diagnostics. This is both a useful
generalization (we expect to have a number of other
DiagnosticConsumers down the road, as Clang does) and is also
important now to avoid a layering violation when adjusting the source
location at the end of a SourceRange to the end of the token.
Swift SVN r850
Module class. Add a new Module.cpp file to implement this (along with
the existing caching strategy, if you're curious). This eliminates the
parallel 'ModuleProvider' heirarchy.
Swift SVN r802
