Instead of building ArgumentShuffleExprs, lets just build a TupleExpr,
with explicit representation of collected varargs and default
arguments.
This isn't quite as elegant as it should be, because when re-typechecking,
SanitizeExpr needs to restore the 'old' parameter list by stripping out
the nodes inserted by type checking. However that hackery is all isolated
in one place and will go away soon.
Note that there's a minor change the generated SIL. Caller default
arguments (#file, #line, etc) are no longer delayed and are instead
evaluated in their usual argument position. I don't believe this actually
results in an observable change in behavior, but if it turns out to be
a problem, we can pretty easily change it back to the old behavior with a
bit of extra work.
TupleShuffleExpr could not express the full range of tuple conversions that
were accepted by the constraint solver; in particular, while it could re-order
elements or introduce and eliminate labels, it could not convert the tuple
element types to their supertypes.
This was the source of the annoying "cannot express tuple conversion"
diagnostic.
Replace TupleShuffleExpr with DestructureTupleExpr, which evaluates a
source expression of tuple type and binds its elements to OpaqueValueExprs.
The DestructureTupleExpr's result expression can then produce an arbitrary
value written in terms of these OpaqueValueExprs, as long as each
OpaqueValueExpr is used exactly once.
This is sufficient to express conversions such as (Int, Float) => (Int?, Any),
as well as the various cases that were already supported, such as
(x: Int, y: Float) => (y: Float, x: Int).
https://bugs.swift.org/browse/SR-2672, rdar://problem/12340004
Before extending TupleShuffleExpr to represent all tuple
conversions allowed by the constraint solver, remove the
parts of TupleShuffleExpr that are no longer needed; this is
support for default arguments, varargs, and scalar-to-tuple and
tuple-to-scalar conversions.
Right now we use TupleShuffleExpr for two completely different things:
- Tuple conversions, where elements can be re-ordered and labels can be
introduced/eliminated
- Complex argument lists, involving default arguments or varargs
The first case does not allow default arguments or varargs, and the
second case does not allow re-ordering or introduction/elimination
of labels. Furthermore, the first case has a representation limitation
that prevents us from expressing tuple conversions that change the
type of tuple elements.
For all these reasons, it is better if we use two separate Expr kinds
for these purposes. For now, just make an identical copy of
TupleShuffleExpr and call it ArgumentShuffleExpr. In CSApply, use
ArgumentShuffleExpr when forming the arguments to a call, and keep
using TupleShuffleExpr for tuple conversions. Each usage of
TupleShuffleExpr has been audited to see if it should instead look at
ArgumentShuffleExpr.
In sequent commits I plan on redesigning TupleShuffleExpr to correctly
represent all tuple conversions without any unnecessary baggage.
Longer term, we actually want to change the representation of CallExpr
to directly store an argument list; then instead of a single child
expression that must be a ParenExpr, TupleExpr or ArgumentShuffleExpr,
all CallExprs will have a uniform representation and ArgumentShuffleExpr
will go away altogether. This should reduce memory usage and radically
simplify parts of SILGen.
For context, String, Nil, Bool, and Int already behave this way.
Note: Swift can compile against 80 or 64 bit floats as the builtin
literal type. Thus, it was necessary to capture this bit somehow in the
FloatLiteralExpr. This was done as another Type field capturing this
info.
For context, String, Nil, and Bool already behave this way.
Note: Before it used to construct (call, ... (integer_literal)), and the
call would be made explicit / implicit based on if you did eg: Int(3) or
just 3. This however did not translate to the new world so this PR adds
a IsExplicitConversion bit to NumberLiteralExpr. Some side results of
all this are that some warnings changed a little and some instructions are
emitted in a different order.
Situations like:
```swift
struct S {}
func foo(_ s: S.Type) {
_ = s()
}
```
Used to be diagnosed in solution application phase, which means that
solver was allowed to formed an incorrect solution.
Currently invalid initializer references are detected and
diagnosed in solution application phase, but that's too
late because solver wouldn't have required information while
attempting to determine the best solution, which might result
in viable solutions being ignored in favour of incorrect ones e.g.
```swift
protocol P {
init(value: Int)
}
class C {
init(value: Int, _: String = "") {}
}
func make<T: P & C>(type: T.Type) -> T {
return T.init(value: 0)
}
```
In this example `init` on `C` would be preferred since it
comes from the concrete type, but reference itself is invalid
because it's an attempt to construct class object using
metatype value via non-required initalizer.
Situations like these should be recognized early and invalid
use like in case of `C.init` should be ranked lower or diagnosed
if that is the only possible solution.
Resolves: rdar://problem/47787705
If the sub-expression of the 'try?' is optional, the result will be the same level of optional-ness.
If the sub-expression is non-optional, the result is optional.
Thus, the following lines all end up with the same type of 'Int?'
- let x = try? 3 as Int
- let x = try? 3 as? Int
- let x = try? 3 as Int?
These types are all allocated on the ASTContext's BumpPtrAllocator,
and by default their destructors are never called. (ModuleDecl is the
exception; it registers its destructor with the ASTContext on
construction.)
No functionality change.
`\.self` is the final chosen syntax. Implement support for this syntax, and remove the stopgap builtin and `WritableKeyPath._identity` property that were in place before.
We previously allowed these closures to default to (), but be inferred
as other types as well, which means that we will find some expressions
to be ambiguous because we end up finding multiple viable solutions
where there is really only one reasonable solution.
Fixes: rdar://problem/42337247
I needed this for materializeForSet remission, but it makes inherited
variadic initializers work, too.
I tried to make this a reasonable starting point for a real language
feature. Here's what's still missing:
- syntax
- semantic restrictions to ensure that the expression isn't written in
invalid places or arbitrarily converted
- SILGen support for expansions that aren't the only variadic argument
rdar://16331406
The storage kind has been replaced with three separate "impl kinds",
one for each of the basic access kinds (read, write, and read/write).
This makes it far easier to mix-and-match implementations of different
accessors, as well as subtleties like implementing both a setter
and an independent read/write operation.
AccessStrategy has become a bit more explicit about how exactly the
access should be implemented. For example, the accessor-based kinds
now carry the exact accessor intended to be used. Also, I've shifted
responsibilities slightly between AccessStrategy and AccessSemantics
so that AccessSemantics::Ordinary can be used except in the sorts of
semantic-bypasses that accessor synthesis wants. This requires
knowing the correct DC of the access when computing the access strategy;
the upshot is that SILGenFunction now needs a DC.
Accessor synthesis has been reworked so that only the declarations are
built immediately; body synthesis can be safely delayed out of the main
decl-checking path. This caused a large number of ramifications,
especially for lazy properties, and greatly inflated the size of this
patch. That is... really regrettable. The impetus for changing this
was necessity: I needed to rework accessor synthesis to end its reliance
on distinctions like Stored vs. StoredWithTrivialAccessors, and those
fixes were exposing serious re-entrancy problems, and fixing that... well.
Breaking the fixes apart at this point would be a serious endeavor.
Several different places in the codebase synthesize IntegerLiteralExprs from computed unsigned variables; each one requires several lines of code and does things slightly differently. Write one central helper method to handle this.
A static reference to DynamicSelfType can only be written as an
implicit member expression where the contextual type is a
DynamicSelfType, ie, 'return .init(...)' in a static method
returning Self.
In this case, the base expression is not a statically-derived
metatype.
These warnings are turning out to be pretty noisy for code that
declares IUOs (e.g. for @IBOutlets) and then passes them to
Objective-C APIs with parameters declared as _Nonnull id.
Since we bridge non-nil values successfully in most cases, and
previuosly written and correctly executing code is either not seeing
nil values passed in or are handling the nil (which is bridged as
NSNull), it seems like a nuisance to warn about these for existing
Swift versions.
We'll conditionalize the warning, and then users can deal with these
when moving to the new language version.
Fixes: rdar://problem/39886178
Fixes a crash for SourceEntityWalker which assumed that a non-implicit TupleExpr has source locations for its name elements.
Fixes SR-6517, rdar://35830880
