We previously relied on the type checker to fill in the implementation
types (swift.Slice<T> and swift.Optional<T>, respectively), which
limited our ability to perform type transformations in the AST. Now,
the AST knows how to form these implementation types on demand.
Swift SVN r7587
This is really two commits in one: first, change the AST and TypeChecker
to only track conformances to known protocols, and second, make sure we
can deserialize decls that conform to known protocols on demand. The
latter is necessary for the type checker to solve constraint systems that
are not fully constrained, and also requires tracking decls with conversion
methods.
Currently decls conforming to known protocols are eagerly deserialized;
that will change soon to be a new ModuleLoader callback. Decls with
conversion functions will continue to be eagerly deserialized for the near
future.
This fixes the initial regressions in making decl deserialization lazy.
Swift SVN r7264
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
We haven't fully updated references to union cases, and enums still are not
their own thing yet, but "oneof" is gone. Long live "union"!
Swift SVN r6783
When we notice that a type implicitly conforms to a protocol but is
not explicitly stated to do so, note this and provide a Fix-It
attaching the conformance to a declaration within the translation
unit, e.g.,
t.swift:28:16: error: type 'S1' does not explicitly conform to protocol 'P'
var p1 : P = S1()
^
t.swift:8:8: note: introduce explicit conformance to protocol 'P'
struct S1 : Q {
^
, P
Swift SVN r6760
Now that we have true serialized modules, the standard library can import
the Builtin module without any special direction (beyond -parse-stdlib),
and anyone can include those modules without special direction.
Swift SVN r6752
Detect duplicate and multiple inheritance, clean up diagnostics, and
unify the code that checks the types in the inheritance clause with
the code that sets the superclass and protocol lists.
Swift SVN r6706
importing them
Because going through the import for every code completion request is slow,
Clang code completion results are cached in the CodeCompletionContext. The
cache needs to be invalidated whenever a new Clang module is loaded. In order
to implement this, ModuleLoadListener class was added.
Swift SVN r6505
If a protocol requirement is satisfied by a generic method, we'll need to save the substitutions necessary to call that method from the witness thunk. This patch adds the spot in the ProtocolConformance::Mapping to save the substitutions; for now, always leave it empty and update the code for the type change.
Swift SVN r6399
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
When checking a type's conformance against a protocol, we can deduce
the values of associated types. Make these associated types visible to
qualified name lookup so that (for example) VectorEnumeratorType does
not need to define the Element type. It is deduced from the signautre
of next(), and made available as, e.g.,
VectorEnumeratorType<Int>.Element through the Enumerator protocol
conformance. Fixes <rdar://problem/11510701>, but with some lingering
dependencies on lazy type resolution (<rdar://problem/12202655>).
Note that the infrastructure here is meant to be generalized to
support default implementations in protocols, but there are several
pieces still not in place.
Swift SVN r6073
When we are interpreting escape sequences in the lexer, we copy the string
literal bytes to ASTContext instead of storing a pointer to the source buffer.
But then we used to try to get a source location for that string in the heap,
which is not a valid source buffer. It succeeds during parsing, but breaks
when we try to print a diagnostic using this location.
Added a verifier check for this.
Also added a real source range for StringLiteralExpr, instead of a source range
with begin == end, produced from the beginning location.
Swift SVN r5961
In order to do this, we need to save and restore parser state easily. The
important pieces of state are:
* lexer position;
* lexical scope stack.
Lexer position can be saved/restored easily. We don't need to store the tokens
for the function body because swift does not have a preprocessor and we can
easily re-lex everything we need. We just store the lexer state for the
beginning and the end of the body.
To save the lexical scope stack, we had to change the underlying data
structure. Originally, the parser used the ScopedHashTable, which supports
only a stack of scopes. But we need a *tree* of scopes. I implemented
TreeScopedHashTable based on ScopedHashTable. It has an optimization for
pushing/popping scopes in a stack fashion -- these scopes will not be allocated
on the heap. While ‘detached’ scopes that we want to re-enter later, and all
their parent scopes, are moved to the heap.
In parseIntoTranslationUnit() we do a second pass over the 'structural AST'
that does not contain function bodies to actually parse them from saved token
ranges.
Swift SVN r5886
This lookup routine takes the place of MemberLookup for AST-level
lookups, which don't consider semantics at all and won't be able to
(for example) perform additional type checking to resolve the
lookup. No functionality change.
Swift SVN r5882
The lookup table for a nominal type declaration provides efficient
(O(1)) access to all of the declarations with a given name in a
nominal type and its extensions. This is architecturally different
from Clang's handling of Objective-C classes and
categories/extensions, where each category/extension has its own
lookup table, and is meant to reduce the number of hash table lookups
required, especially once these hash tables are stored in the module.
The lookup table is built and updated lazily as extensions and members
are introduced, similarly to Clang's lookup tables. However, the
simpler name lookup rules in Swift (vs. C/C++/Objective-C) make this
approach actually semantically correct.
Swift SVN r5874
This causes the SourceLoader to recursively parse the imported module in standard
library mode, giving it access to the Builtin module.
This is all a terrible hack and should be ripped out with great victory someday, but
until we have binary modules that persist the build setting used to produce the
module, this is the best we can do.
Swift SVN r5847
Keep track of each of the nominal type declarations and extensions
thereof that conform to each protocol. When the type checker runs out
of other ideas for a type variable, enumerate the types known to
conform to the protocols it requires. Fixes <rdar://problem/14014895>
and eliminates the extra casts introduced in r5639.
Swift SVN r5645
This flag makes ASTContext and SILModule's allocators go through malloc instead of using bump pointer allocators, so that GuardMalloc or similar tools can be used to look for memory bugs.
Swift SVN r5472
If -nsstring-is-string is enabled, lower Strings in cc(c) and cc(objc) function types to NSString, and when calling them, insert calls to StringToNSString/NSStringToString to perform the bridging conversion.
This isn't quite ready for prime-time yet, because we still need to emit the inverse bridging for ObjC method thunks, and I haven't tested the IRGen end of things yet.
Swift SVN r5355
This replaces the obscure, inefficient lookup into extensions with
something more straightforward: walk all of the known extensions
(available as a simple list), then eliminate any declarations that
have been shadowed by other declarations. The shadowing rules still
need to consider the module re-export DAG, but we'll leave that for
later.
As part of this, keep track of the last time we loaded extensions for
a given nominal type. If the list of extensions is out-of-date with
respect to the global generation count (which tracks resolved module
imports), ask the modules to load any additional extensions. Only the
Clang module importer can currently load extensions in this manner.
Swift SVN r5223
This paves the way for having a Swift module importer. The eventual goal
here is to eliminate all explicit uses of the Clang module loader, but
I'm not going to push too hard on that for now.
Swift SVN r5092
Keep track of external definitions as they are created by broadcasting
them through a mutation listener interface. At name binding time, we
just cache them. When a type checker is alive, it immediately performs
any additional operations necessary on those types (e.g., declaring
implicit constructors).
This also eliminates some O(N^2) behavior in the type checker as well,
because we don't have to walk through all of the module imports to
find the external definitions. We just keep a single list in the
ASTContext along with our place in the list.
Fixes <rdar://problem/13769497>.
Swift SVN r5032
Archetypes and projected existentials have the type %swift.opaque* and not i8*, so I need a corresponding SIL type to be able to model the ProjectExistential operation. We might also end up needing the builtin type for other low-level things down the line.
Swift SVN r3793
There is no protection whatsoever if the Clang-to-Swift type
conversion produces something that Swift doesn't lower in an
ABI-compatible way. That will be dealt with later.
Swift SVN r3249
From a user's perspective, one imports Clang modules using the normal
Swift syntax for module imports, e.g.,
import Cocoa
However, to enable importing Clang modules, one needs to point Swift
at a particular SDK with the -sdk= argument, e.g.,
swift -sdk=/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9M.sdk
and, of course, that SDK needs to provide support for modules.
There are a number of moving parts here. The major pieces are:
CMake support for linking Clang into Swift: CMake users will now need
to set the SWIFT_PATH_TO_CLANG_SOURCE and SWIFT_PATH_TO_CLANG_BUILD
to the locations of the Clang source tree (which defaults to
tools/clang under your LLVM source tree) and the Clang build tree.
Makefile support for linking Clang into Swift: Makefile users will
need to have Clang located in tools/clang and Swift located in
tools/swift, and builds should just work.
Module loader abstraction: similar to Clang's module loader,
a module loader is responsible for resolving a module name to an
actual module, loading that module in the process. It will also be
responsible for performing name lookup into that module.
Clang importer: the only implementation of the module loader
abstraction, the importer creates a Clang compiler instance capable of
building and loading Clang modules. The approach we take here is to
parse a dummy .m file in Objective-C ARC mode with modules enabled,
but never tear down that compilation unit. Then, when we get a request
to import a Clang module, we turn that into a module-load request to
Clang's module loader, which will build an appropriate module
on-the-fly or used a cached module file.
Note that name lookup into Clang modules is not yet
implemented. That's the next major step.
Swift SVN r3199
This introduces the notion of arenas into ASTContext, with two arenas
currently defined: one for 'permanent' storage, and another for the
current constraint checker. The latter is used when allocating any
types that involve type variables, which are only used temporarily
during type checking anyway.
This gives us a 1% speedup on swift.swift (because we're hitting
smaller hash tables when doing lookups) and < 1% memory reduction
(since that's not the main source of memory usage). It's more
important architecturally, so our memory usage doesn't grow with the
number of type-checks performed.
Note also that this arena scheme could be generalized, which we may
very well want to do in the future. For example, we could easily have
an arena for temporary nodes introduced by parsing (e.g.,
UnresolvedDeclRefExpr) or by name binding (OverloadedDeclRefExpr), and
clear that arena when we successfully move onto the next phase. Or, in
a REPL/debugger context, have a 'temporary' arena for
statements/expressions that can be removed.
Swift SVN r3175
types in a few ways:
- Actually check the extra requirements placed on associated types,
e.g., "T.Element : Ordered"
- Actually encode/store the protocol conformance information for a
BoundGenericType in the same way that we do for SpecializeExpr,
GenericMemberRefExpr, and GenericSubscriptExpr. Yay, consistency.
- Move the storage for the protocol conformance information into a
DenseMap in the ASTContext indexed by canonical BoundGenericType, so
it doesn't require inline storage in BoundGenericType.
Swift SVN r2517
type substitution for a nested type reference (Foo.Bar.Wibble) whose
substituted parent reference (Foo.Bar) yields an archetype can simply
look for the appropriate nested type in the archetype.
This allows us to eliminate the hideous ASTContext::AssociatedTypeMap
and simply the archetype builder.
Swift SVN r2438
functions. This involves a few steps:
- When assigning archetypes to type parameters, also walk all of the
protocols to which the type parameter conforms and assign archetypes
to each of the associated types.
- When performing name lookup into an archetype, look into all of
the protocols to which it conforms. If we find something, it can be
referenced via the new ArchetypeMemberRefExpr.
- When type-checking ArchetypeMemberRefExpr, substitute the values
of the various associated types into the type of the member, so the
resulting expression involves the archetypes for the enclosing
generic method.
The rest of the type checking essentially follows from the fact that
archetypes are unique types which (therefore) have no behavior beyond
what is provided via the protocols they conform to. However, there is
still much work to do to ensure that we get the archetypes set up
correctly.
Swift SVN r2201
using the term "unresolved" in expressions for a while, and it fits
for types better than "dependent type."
The term "dependent type" will likely come back at some point to mean
"involves an archetype".
Swift SVN r1962
archetypes. Use this substitution when checking the
variable/function/subscript witnesses during protocol conformance.
This allows us to check the conforms-to relationship for the Range
protocol as we want to express it.
Swift SVN r1945
wrap it in an 'id' type in the standard library.
Also fix a bug noticed by inspection where initWithTake for
function types wasn't entering a cleanup for the taken value.
This probably doesn't matter for existing possibilities, but
it's potentially important under exceptions.
Swift SVN r1902
This is <rdar://problem/10217868>. Apparently I'm using Lion's
libc++ headers somehow, which I should probably fix; but since
the use of shared_ptr is just a hack until DenseMap supports
move-only types, I don't feel bad about changing it to a different
hack that avoids shared_map altogether.
Swift SVN r1897
