This was blocked by some type-checker issues:
First, we weren't registering a constraint restriction when
tail-recursing in matchTypes (as opposed to when creating
a disjunction because multiple conversions applied). Do so,
and move the set of constraint restrictions to the constraint
system in order to make this simpler. A large amount of similar
solver state is already there, and of course solving the system
already prospectively modifies the constraint graph.
Second, only set up a potential existential conversion when
working with concrete types. Without this, we would fail to
typecheck conversions to optional protocol types, but not
optional class/struct/whatever types. It's not clear whether
whether we should ever really be considering conversions when
either of the types is non-concrete.
I believe it was the second fix which removed a need for a !
in the NewArray test case.
Swift SVN r14637
When type checking constructors, ensure that any upstream errors in the resolution of the self type are accounted for (rather than assuming that the self type is always well-formed). Not doing so can be especially problematic within the context of a type extension, since there may not even be a self type to resolve to.
Swift SVN r13506
its basic logic in libAST, which both makes it easier to
implement and makes it possible to use in the places that
should care about it, i.e. in IR-gen and SIL-gen.
Per Doug, none of the places that were introducing
trivial-subtype constraints really needed to do so rather
than just using subtype constraints.
Swift SVN r12679
with qualifiers on it, we have two distinct types:
- LValueType(T) aka @lvalue T, which is used for mutable values on the LHS of an
assignment in the typechecker.
- InOutType(T) aka @inout T, which is used for @inout arguments, and the implicit
@inout self argument of mutable methods on value types. This type is also used
at the SIL level for address types.
While I detangled a number of cases that were checking for LValueType (without checking
qualifiers) and only meant @inout or @lvalue, there is more to be done here. Notably,
getRValueType() still strips @inout, which is totally and unbearably wrong.
Swift SVN r11727
- Switch all the 'self' mutable arguments to take self as @inout, since
binding methods to uncurried functions expose them as such.
- Eliminate the subtype relationship between @inout and @inout(implicit),
which means that we eliminate all sorts of weird cases where they get
dropped (see the updated testcases).
- Eliminate the logic in adjustLValueForReference that walks through functions
converting @inout to @inout(implicit) in strange cases.
- Introduce a new set of type checker constraints and conversion kinds to properly
handle assignment operators: when rebound or curried, their input/result argument
is exposed as @inout and requires an explicit &. When applied directly (e.g.
as ++i), they get an implicit AddressOfExpr to bind the mutated lvalue as an
@inout argument.
Overall, the short term effect of this is to fix a few old bugs handling lvalues.
The long term effect is to drive a larger wedge between implicit and explicit
lvalues.
Swift SVN r11708
Previously, we had an artificial separation between the subexpression
"x" and the context of the expression "x as T". This breaks down when
the subexpression includes a reference to an anonymous closure
argument (e.g., $0) from a single-expression closure. By merging the
systems, we fix the crasher (<rdar://problem/15633178>) and allow
improved type inference for these expressions.
Swift SVN r11235
Rather than performing a two-pass walk over all of the constraints in
the system to attach them to type variables, use the existing type
variable -> constraints mapping in the constraint graph to make this a
faster single-pass process. Also clarify the type bindings a little
bit. Improves type checking time for the standard library by ~3%.
Swift SVN r11098
This shaves about 10% off the number of solution states explored when
type-checking the standard library, although it doesn't improve
overall time by much. In a more targeted benchmark, 1 + 2.0 + 1, we
get a 21% speedup.
Swift SVN r11033
