The witnesses in a NormalProtocolConformance have never been
completely serialized, because their substitutions involved a weird
mix of archetypes that blew up the deserialization code. So, only the
witness declarations themselves got serialized. Many clients (the type
checker, SourceKit, etc.) didn't need the extra information, but some
clients (e.g., the SIL optimizers) would end up recomputing this
information. Ick.
Now, serialize the complete Witness structure along with the AST,
including information about the synthetic environment, complete
substitutions, etc. This should obsolete some redundant code paths in
the SIL optimization infrastructure.
This (de-)serialization code takes a new-ish approach to serializing
the synthetic environment in that it avoids serializing any
archetypes. Rather, it maps everything back to interface types during
serialization, and deserialization forms a new generic environment
(with new archetypes!) on-the-fly, mapping deserialized types back
into that environment (and to those archetypes). This way, we don't
have to maintain identity of archetypes in the deserialization code,
and might get some better re-use of the archetypes.
More of rdar://problem/24079818.
We don't want the machine calling conventions for closure invocation functions to necessarily be tied to the convention for normal thin functions or methods. NFC yet; for now, 'closure' follows the same behavior as the 'method' convention, but as part of partial_apply simplification it will be a requirement that partial_apply takes a @convention(closure) function and a box and produces a @convention(thick) function from them.
llvm r283043 and possibly other recent changes switch to use StringRef
instead of char* pointers. Update Swift to match. In some cases, this is
a clear improvement. It would be good to assess the impact on memory use,
particularly for the Filename component of source locations.
Note that the change to SILLocation::isNull fixes an apparent bug where
the location was treated as null when the filename was *not* null.
Sugared GenericTypeParamTypes point to GenericTypeParamDecls,
allowing the name of the parameter as written by the user to be
recovered. Canonical GenericTypeParamTypes on the other hand
only store a depth and index, without referencing the original
declaration.
When printing SIL, we wish to output the original generic parameter
names, even though SIL only uses canonical types. Previously,
we used to accomplish this by mapping the generic parameter to an
archetype and printing the name of the archetype. This was not
adequate if multiple generic parameters mapped to the same
archetype, or if a generic parameter was mapped to a concrete type.
The new approach preserves the original sugared types in the
GenericEnvironment, adding a new GenericEnvironment::getSugaredType()
method.
There are also some other assorted simplifications made possible
by this.
Unfortunately this makes GenericEnvironments use a bit more memory,
however I have more improvements coming that will offset the gains,
in addition to making substitution lists smaller also.
This is another problem (like 5356cc3) exposed by building with a newer
version of Clang. Construct a temporary SmallVector when needed to create
an ArrayRef.
This would have allowed us to triage rdar://problem/28305755 much
sooner. The actual problem is pretty bad: if you have too many methods
with the same selector, serialization just falls over. "Too many" is
in the thousands, which seems unlikely, but 'dealloc' can actually get
there if there are a lot of little classes, and 'init' might as well,
so we really should do better here.
RequirementReprs stored serialized references to archetypes,
which do not have enough information to reconstruct same-type
requirements.
For this reason, we would serialize the 'as written' requirement
string as well as the actual types, which is a horrible hack.
Now that the ASTPrinter and SourceKit use GenericSignatures,
none of this is needed anymore.
There's a bit of a hack to deal with generic typealiases, but
overall this makes things more logical.
This is the last big refactoring before we can allow constrained
extensions to make generic parameters concrete. All that remains
is a small set of changes to SIL type lowering, and retooling
some diagnostics in Sema.
Long term, we want to refactor the AST to reflect the current
programming model in Swift. This would include refactoring
FunctionType to take a list of ParameterTypeElt, or something with a
better name, that can contain both the type and flags/bits that are
only specific to types in parameter position, such as @autoclosure and
@escaping. At the same time, noescape-by-default has severely hurt our
ability to print types without significant context, as we either have
to choose to too aggressively print @escaping or not print it in every
situation it occurs, or both.
As a gentle step towards the final solution, without uprooting our
overall AST structure, and as a way towards fixing the @escaping
printing ails, put these bits on the TupleTypeElt and ParenType, which
will serve as a model for what ParameterTypeElt will be like in the
future. Re-use these flags on CallArgParam, to leverage shared
knowledge in the type system. It is a little painful to tack onto
these types, but it's minor and will be overhauled soon, which will
eventually result in size savings and less complexity overall.
This includes all the constraint system adjustments to make these
types work and influence type equality and overload resolution as
desired. They are encoded in the module format. Additional tests
added.
This flag switches the "effective language version" of the compiler,
at least to any version supported (as of this change: "3" or "3.0").
At the moment nothing uses it except the language version build
configuration statements (#if swift(...)) and various other places
that report, encode, or otherwise check version numbers.
In the future, it's intended as scaffolding for backwards compatibility.
Fixes SR-2582
The new instructions are: ref_tail_addr, tail_addr and a new attribute [ tail_elems ] for alloc_ref.
For details see docs/SIL.rst
As these new instructions are not generated so far, this is a NFC.
The new instructions are: ref_tail_addr, tail_addr and a new attribute [ tail_elems ] for alloc_ref.
For details see docs/SIL.rst
As these new instructions are not generated so far, this is a NFC.
We were optimizing away unused pattern binding initializer contexts in
both the parser and in semantic analysis, which led to a
somewhat-unpredictable set of DeclContexts in the AST. Normalize
everything by always creating these contexts.
Now that SILFunctions no longer reference a GenericParamList, we
don't need to de-serialize cross-module references to archetypes
anymore.
This was the last remaining usage of AllArchetypes, so we can
finally rip it out.
A GenericEnvironment stores the mapping between GenericTypeParamTypes
and context archetypes (or eventually, concrete types, once we allow
extensions to constrain a generic parameter to a concrete type).
The goals here are two-fold:
- Eliminate the GenericTypeParamDecl::getArchetype() method, and
always use mapTypeIntoContext() instead
- Replace SILFunction::ContextGenericParams with a GenericEnvironment
This patch adds the new data type as well as serializer and AST
verifier support. but nothing else uses it yet.
Note that GenericSignature::get() now asserts if there are no
generic parameters, instead of returning null. This requires a
few tweaks here and there.
I don't see any tests failing with this code removed; I guess
either the duplicate archetype issue no longer occurs, or does
not matter since we use interface types almost everywhere
when talking about Decls from other modules.
- If a parameter type is a sugared function type, mark the type
as non-escaping by default. Previously, we were only doing this
if the parameter type was written as a function type, with no
additional sugar.
This means in the following cases, the function parameter type
is now non-escaping:
func foo(f: ((Int) -> Void))
typealias Fn = (Int) -> Void
func foo(f: Fn)
- Also, allow @escaping to be used in the above cases:
func foo(f: @escaping ((Int) -> Void))
typealias Fn = (Int) -> Void
func foo(f: @escaping Fn)
- Diagnose usages of @escaping in inappropriate locations, instead
of just ignoring them.
It is unfortunate that sometimes we end up desugaring the typealias,
but currently there are other cases where this occurs too, such as
qualified lookpu of protocol typealiases with a concrete base
type, and generic type aliases. A more general representation for
sugared types (such as an AttributedType sugared type) would allow
us to solve this in a more satisfactory manner in the future.
However at the very least this patch factors out the common code
paths and adds comments, so it shouldn't be too bad going forward.
Note that this is a source-breaking change, both because @escaping
might need to be added to parameters with a sugared function type,
and @escaping might be removed if it appears somewhere where we
do not mark function types as non-escaping by default.
One minor revision: this lifts the proposed restriction against
overriding a non-open method with an open one. On reflection,
that was inconsistent with the existing rule permitting non-public
methods to be overridden with public ones. The restriction on
subclassing a non-open class with an open class remains, and is
in fact consistent with the existing access rule.
The isExplicitlyEscaping bit, though useful for printing,
unfortunately puts us in a position where we have different bit
patterns for the same type, and thus lose much of our type equivalence
checking for overriding, protocol conformance, etc., even if we were
to take subtyping into account. We need to drop it, relying on the
existing noescape bit alone to determine the type's semantics (at
least, as long as we continue to encode this information in the type
system).
This is a partial fix; we will now be excessively printing @escaping,
but the subsequent commits will correct this. For printing, we will
instead need to be more context-aware.
What I've implemented here deviates from the current proposal text
in the following ways:
- I had to introduce a FunctionArrowPrecedence to capture the parsing
of -> in expression contexts.
- I found it convenient to continue to model the assignment property
explicitly.
- The comparison and casting operators have historically been
non-associative; I have chosen to preserve that, since I don't
think this proposal intended to change it.
- This uses the precedence group names and higherThan/lowerThan
as agreed in discussion.
'fileprivate' is considered a broader level of access than 'private',
but for now both of them are still available to the entire file. This
is intended as a migration aid.
One interesting fallout of the "access scope" model described in
758cf64 is that something declared 'private' at file scope is actually
treated as 'fileprivate' for diagnostic purposes. This is something
we can fix later, once the full model is in place. (It's not really
/wrong/ in that they have identical behavior, but diagnostics still
shouldn't refer to a type explicitly declared 'private' as
'fileprivate'.)
As a note, ValueDecl::getEffectiveAccess will always return 'FilePrivate'
rather than 'Private'; for purposes of optimization and code generation,
we should never try to distinguish these two cases.
This should have essentially no effect on code that's /not/ using
'fileprivate' other than altered diagnostics.
Progress on SE-0025 ('fileprivate' and 'private')
In Swift, default arguments are associated with a function or
initializer's declaration---not with its type. This was not always the
case, and TupleType's ability to store a default argument kind is a
messy holdover from those dark times.
Eliminate the default argument kind from TupleType, which involves
migrating a few more clients over to declaration-centric handling of
default arguments. Doing so is usually a bug-fix anyway: without the
declaration, one didn't really have
The SILGen test changes are due to a name-mangling fix that fell out
of this change: a tuple type is mangled differently than a non-tuple
type, and having a default argument would make the parameter list of a
single-parameter function into a tuple type. Hence,
func foo(x: Int = 5)
would get a different mangling from
func foo(x: Int)
even though we didn't actually allow overloading.
Fixes rdar://problem/24016341, and helps us along the way to SE-0111
(removing the significance of argument labels) because argument labels
are also declaration-centric, and need the same information.
This flag tracks whether we have a special kind of imported class
that has limitations in what you can do with it. Currently it's
used for two things: CF classes, and the magic "Protocol" class used
to represent Objective-C protocol metadata. I'm planning to add a
third to handle classes with the recently-added objc_runtime_visible
attribute, which describes an Objective-C class whose runtime symbols
are hidden (forcibly preventing categories and subclassing). This is
used for some of the types in Dispatch, which has exposed some of the
classes that were considered implementation details on past OSs.
I'm splitting the flag into an enum rather than just marking the
Dispatch classes with the existing flag because we still need to
be able to /cast/ to the Dispatch types (which you can't do with CF
types today) and because they deserve better than to be lumped in
with CF for diagnostic purposes.
Groundwork for rdar://problem/26850367, which is that Swift will
happily let you extend the new Dispatch classes but then fails to find
the symbols at link-time.
not have access to their type arguments at runtime. Use this to
fix the emission of native thunks for imported ObjC-generic
initializers, since they may need to perform bridging.
For now, pseudo-genericity is all-or-nothing, but we may want to
make it apply only to certain type arguments.
Also, clean up some code that was using dead mangling nodes.
The verifier now asserts that Throws, ThrowsLoc and isBodyThrowing()
match up.
Also, add /*Label=*/ comments where necessary to make the long argument
lists easier to read, and cleaned up some inconsistent naming conventions.
I caught a case where ClangImporter where we were passing in a loc as
StaticLoc instead of FuncLoc, but probably this didn't affect anything.
...with a better message than the generic "older version of the
compiler" one, when we know it's actually a different version of
Swift proper.
This still uses the same internal module version numbers to check
if the module is compatible; the presentation of language versions
is a diagnostic thing only.
Speaking of module version numbers, this deliberately does NOT
increment VERSION_MINOR; it's implemented in a backwards-compatible
way.
This will only work going forwards, of course; all existing modules
don't have a short version string, and I don't feel comfortable
assuming all older modules we might encounter are "Swift 2.2".
rdar://problem/25680392
We want to distinguish the special case of a library built with
-sil-serialize-all, from a SIL function that is [fragile] because
of an explicitly @_transparent or @inline(__always).
For now, NFC.
This was mistakenly reverted in an attempt to fix buildbots.
Unfortunately it's now smashed into one commit.
---
Introduce @_specialize(<type list>) internal attribute.
This attribute can be attached to generic functions. The attribute's
arguments must be a list of concrete types to be substituted in the
function's generic signature. Any number of specializations may be
associated with a generic function.
This attribute provides a hint to the compiler. At -O, the compiler
will generate the specified specializations and emit calls to the
specialized code in the original generic function guarded by type
checks.
The current attribute is designed to be an internal tool for
performance experimentation. It does not affect the language or
API. This work may be extended in the future to add user-visible
attributes that do provide API guarantees and/or direct dispatch to
specialized code.
This attribute works on any generic function: a freestanding function
with generic type parameters, a nongeneric method declared in a
generic class, a generic method in a nongeneric class or a generic
method in a generic class. A function's generic signature is a
concatenation of the generic context and the function's own generic
type parameters.
e.g.
struct S<T> {
var x: T
@_specialize(Int, Float)
mutating func exchangeSecond<U>(u: U, _ t: T) -> (U, T) {
x = t
return (u, x)
}
}
// Substitutes: <T, U> with <Int, Float> producing:
// S<Int>::exchangeSecond<Float>(u: Float, t: Int) -> (Float, Int)
---
[SILOptimizer] Introduce an eager-specializer pass.
This pass finds generic functions with @_specialized attributes and
generates specialized code for the attribute's concrete types. It
inserts type checks and guarded dispatch at the beginning of the
generic function for each specialization. Since we don't currently
expose this attribute as API and don't specialize vtables and witness
tables yet, the only way to reach the specialized code is by calling
the generic function which performs the guarded dispatch.
In the future, we can build on this work in several ways:
- cross module dispatch directly to specialized code
- dynamic dispatch directly to specialized code
- automated specialization based on less specific hints
- partial specialization
- and so on...
I reorganized and refactored the optimizer's generic utilities to
support direct function specialization as opposed to apply
specialization.
Temporarily reverting @_specialize because stdlib unit tests are
failing on an internal branch during deserialization.
This reverts commit e2c43cfe14, reversing
changes made to 9078011f93.
This attribute can be attached to generic functions. The attribute's
arguments must be a list of concrete types to be substituted in the
function's generic signature. Any number of specializations may be
associated with a generic function.
This attribute provides a hint to the compiler. At -O, the compiler
will generate the specified specializations and emit calls to the
specialized code in the original generic function guarded by type
checks.
The current attribute is designed to be an internal tool for
performance experimentation. It does not affect the language or
API. This work may be extended in the future to add user-visible
attributes that do provide API guarantees and/or direct dispatch to
specialized code.
This attribute works on any generic function: a freestanding function
with generic type parameters, a nongeneric method declared in a
generic class, a generic method in a nongeneric class or a generic
method in a generic class. A function's generic signature is a
concatenation of the generic context and the function's own generic
type parameters.
e.g.
struct S<T> {
var x: T
@_specialize(Int, Float)
mutating func exchangeSecond<U>(u: U, _ t: T) -> (U, T) {
x = t
return (u, x)
}
}
// Substitutes: <T, U> with <Int, Float> producing:
// S<Int>::exchangeSecond<Float>(u: Float, t: Int) -> (Float, Int)
Let's say I am a good citizen and document my private symbols:
/** My TOP SECRET DOCUMENTATION */
private class Foo {
}
When I go to distribute the compiled binary, I find out my private
documentation is distributed as well:
$ swiftc test.swift -emit-module -module-name "test"
$ strings test.swiftdoc
My TOP SECRET DOCUMENTATION
/** My TOP SECRET DOCUMENTATION */
If a client can't use a symbol (e.g. it's private [or internal and not
-enable-testing]) don't emit the documentation for a symbol in the
swiftdoc.
Fixes: SR-762, rdar://21453624
The test coverage implements this truth table:
| visibility | -enable-testing | documentation? |
|------------|-----------------|----------------|
| private | no | ❌ |
| internal | no | ❌ |
| public | no | ✅ |
| private | yes | ❌ |
| internal | yes | ✅ |
| public | yes | ✅ |
Modified the existing comments test coverage to expect non-public
documentation not to be emitted.
Don't rely on existing comment structure
Refuse to emit comments if the decl cannot actually have one. To
accomplish this, we move `canHaveComment` into the Decl instance. It
must also be marked `const`, since one of its existing usages operates
on a const pointer.
Perform fewer checks when serializing the standard library.
