This allows an elegant design in which we can still allocate RawSyntax
nodes using a bump allocator but are able to automatically free that
buffer once the last RawSyntax node within that buffer is freed.
This also resolves a memory leak of RawSyntax nodes that was caused by
ParserUnit not freeing its underlying ASTContext.
Wire up the request-evaluator with an instance in ASTContext, and
introduce two request kinds: one to retrieve the superclass of a class
declaration, and one to compute the type of an entry in the
inheritance clause.
Teach ClassDecl::getSuperclass() to go through the request-evaluator,
centralizing the logic to compute and extract the superclass
type.
Fixes the crasher from rdar://problem/26498438.
Introduced during the bring-up of the generics system in July, 2012,
Substitution (and SubstitutionList) has been completely superseded by
SubstitutionMap. R.I.P.
This removes the default implementation of hash(into:), and replaces it with automatic synthesis built into the compiler. Hashable can now be implemented by defining either hashValue or hash(into:) -- the compiler supplies the missing half automatically, in all cases.
To determine which hash(into:) implementation to generate, the synthesizer resolves hashValue -- if it finds a synthesized definition for it, then the generated hash(into:) body implements hashing from scratch, feeding components into the hasher. Otherwise, the body implements hash(into:) in terms of hashValue.
Before conditional conformances, the archetypes in conformance
extensions (i.e. extension Foo: SomeProtocol) were equivalent to those
in the type decl, with the same protocol bounds and so on. The code for
printing "synthesized" members relied on this fact. This commit teaches
that code to deal with archetypes in the conditional conformance
extension when required.
Fixes rdar://problem/36553066 and SR-6930.
Also remove the decl from the known decls and remove a
bunch of code referencing that decl as well as a bunch of other
random things including deserialization support.
This includes removing some specialized diagnostics code that
matched the identifier ImplicitlyUnwrappedOptional, and tweaking
diagnostics for various modes and various issues.
Fixes most of rdar://problem/37121121, among other things.
Introduced SyntaxArena for managing memory and cache.
SyntaxArena holds BumpPtrAllocator as a allocation storage.
RawSyntax is now able to be constructed with normal heap allocation, or
by SyntaxArena. RawSyntax has ManualMemory flag which indicates it's managed by
SyntaxArena. If the flag is true, its Retain()/Release() is no-op thus it's
never destructed by IntrusiveRefCntPtr.
This speedups the memory allocation for RawSyntax.
Also, in Syntax parsing, "token" RawSyntax is reused if:
a) It's not string literal with >16 length; and
b) It doesn't contain random text trivia (e.g. comment).
This reduces the overall allocation cost.
Sometimes we end up mapping a conformance into and then out of a
particular context, which led to "stacked" specialized conformances
that were basically a no-op. Look through these to collapse them
eagerly.
Collapses 15786 conformances in the standard library.
Swift's ASTContext contained all of the logic to find the complete list
of properties for an Objective-C class, which is used by the Clang importer
to influence the mapping of Objective-C names into Swift. Swift's
ASTContext also included a *cache* for this information, indexed by
the Clang `ObjCInterfaceDecl *`. However, this cache was getting
populated/queried from the Clang importer's name importer, such that
the keys would be Clang declarations used to build modules and then
deallocated. If that memory eventually gets reused for a different
`ObjCInterfaceDecl *`, we would get incorrect/stale all-properties
information.
Almost Surely fixes rdar://problem/35347167, which is a
nondeterministic failure where UIView's `addGestureRecognizer(_:)` gets
occasionally imported as `add(_:)`.
Now that the GenericSignatureBuilder is no longer sensitive to the input
module, stop uniquing the canonical GSBs based on that module. The main
win here is when deserializing a generic environment: we would end up
creating a canonical GSB in the module we deserialized and another
canonical GSB in the module in which it is used.
Once we compute a generic signature from a generic signature builder,
all queries involving that generic signature will go through a separate
(canonicalized) builder, and the original builder can no longer be used.
The canonicalization process then creates a new, effectively identical
generic signature builder. How silly.
Once we’ve computed the signature of a generic signature builder, “register”
it with the ASTContext, allowing us to move the existing generic signature
builder into place as the canonical generic signature builder. The builder
requires minimal patching but is otherwise fully usable.
Thanks to Slava Pestov for the idea!
For enums, we now only call _mixInt on the computed hash value if
it has associated values; for enums without associated values, we
use the ordinal alone, as before.
Once we compute a generic signature from a generic signature builder,
all queries involving that generic signature will go through a separate
(canonicalized) builder, and the original builder can no longer be used.
The canonicalization process then creates a new, effectively identical
generic signature builder. How silly.
Once we’ve computed the signature of a generic signature builder, “register”
it with the ASTContext, allowing us to move the existing generic signature
builder into place as the canonical generic signature builder. The builder
requires minimal patching but is otherwise fully usable.
Thanks to Slava Pestov for the idea!
Given an existential type E, this creates a new canonical
generic signature <T : E>.
If E is a protocol composition containing members of protocol,
class or AnyObject type, the resulting generic signature will
split up the T : E requirement into a canonical and minimal
set of conformance, superclass and layout requirements.
If/when we implement generalized existentials, existential
types will be defined in terms of an arbitrary set of
generic requirements applied to a single generic parameter;
at that point, this method will be replaced with a generic
signature stored inside the type itself.
For now, this will be used to simplify some logic in the
SILOptimizer.
This implementation required a compromise between parser
performance and AST structuring. On the one hand, Parse
must be fast in order to keep things in the IDE zippy, on
the other we must hit the disk to properly resolve 'canImport'
conditions and inject members of the active clause into the AST.
Additionally, a Parse-only pass may not provide platform-specific
information to the compiler invocation and so may mistakenly
activate or de-activate branches in the if-configuration decl.
The compromise is to perform condition evaluation only when
continuing on to semantic analysis. This keeps the parser quick
and avoids the unpacking that parse does for active conditions
while still retaining the ability to see through to an active
condition when we know we're moving on to semantic analysis anyways.
Recently support was added for '-swift-version 5' to the frontend.
Right now we only have an isSwiftVersion3() check which returns 'true'
if the version is 3, and returns 'false' if it is 4 or 5. This was used
during Swift 4.0 development to guard various legacy behaviors that we
wish to deprecate.
Going forward, when do not want to add isSwiftVersion4() and
isSwiftVersion5() checks, because they're too fragile; if a new
behavior is introduced in Swift 5 that we wish to disable in Swift 3
and Swift 4 mode, checking for isSwiftVersion5() is insufficient,
because eventually Swift 6 will roll around, and presumably one would
expect the new behavior to take effect in Swift 6 mode as well.
I think a better solution is a 'isSwiftVersionAtLeast()' check, which
checks if the major version number is greater than or equal to the
given value.
We could refactor the existing 'isSwiftVersion3()' checks to instead
do '!isSwiftVersionAtLeast(4)', but I'm going to hold off on doing that
for now.
Rather than having `ASTContext:: getOrCreateCanonicalGenericEnvironment()`
ask its `GenericSignatureBuilder` parameter recompute the generic signature
at nontrivial cost, just pass the known signature through.
When casting from an object type to a bridged Swift value type, classifyDynamicCast would use the cast classification for the target type's bridged object type, which would be trivially WillSucceed for thinks like NSNumber-to-Int or NSError-to-SomeError, even though the bridging itself could fail. Fixing this fixes SR-2920|rdar://problem/31404281.
ASTContext::getSpecializedConformance() already copies the
substitutions, so remove some AllocateCopy() calls.
Also, add a new overload taking a SubstitutionMap instead.
This allows removing some gatherAllSubstitutions() calls,
which have an allocation inside them.
Finally, remove the now-unused ModuleDecl parameter from
ProtocolConformance::subst() and make it public.
This has the effect of propagating the search path to the clang importer as '-iframework'.
It doesn't affect whether a swift module is treated as system or not, this can be done as follow-up enhancement.
