When `@_silgen_name` is applied to a function with no body, it is a forward
declaration. It therefore must be treated as an external (public) declaration
regardless of the access level it was given in source.
Resolves rdar://141436934.
Previously, when determining and completing lifetimes of scoped
addresses, `computeTransitiveLiveness` was used to determine the
liveness used for completing the lifetime.
That approach had two problems:
(1) The function does not find scope-ending uses of `load_borrow`s.
The result was determining that the lifetime of the enclosing
`store_borrow` ended before that of the `load_borrow`.
(2) The function did not complete lifetimes of values defined within the
scoped address whose lifetimes the scoped address had to contain.
This was an inconsistency between the handling of scoped addresses
and that of values.
Here, both are addressed by implementing a `TransitiveAddressWalker` (as
`computeTransitiveLiveness`'s callee does) which not only visits
existing `end_borrow`s of `load_borrows` but completes them (and other
inner guaranteed values or scoped addresses).
rdar://141246601
This enables access enforcement analysis to classify a dynamic begin_access in
access patterns (such as the one below) involving a throwing function as not
having nested conflicts.
```
struct Stack {
var items : [UInt8]
mutating func pop() throws -> UInt8 {
guard let item = items.popLast() else { throw SomeErr.err }
return item
}
...
}
class Container {
private var ref : Stack
@inline(never)
internal func someMethod() throws {
try ref.pop()
}
...
}
```
rdar://141182074
Complete scopes of scoped addresses (introduced by `store_borrow` and
`begin_access`) in dead end blocks via
`ScopedAddressValue::computeTransitiveLiveness`.
rdar://141037060
Many APIs using nonescapable types would like to vend interior pointers to their
parameter bindings, but this isn't normally always possible because of representation
changes the caller may do around the call, such as moving the value in or out of memory,
bridging or reabstracting it, etc. `@_addressable` forces the corresponding parameter
to be passed indirectly in memory, in its maximally-abstracted representation.
[TODO] If return values have a lifetime dependency on this parameter, the caller must
keep this in-memory representation alive for the duration of the dependent value's
lifetime.
Type annotations for instruction operands are omitted, e.g.
```
%3 = struct $S(%1, %2)
```
Operand types are redundant anyway and were only used for sanity checking in the SIL parser.
But: operand types _are_ printed if the definition of the operand value was not printed yet.
This happens:
* if the block with the definition appears after the block where the operand's instruction is located
* if a block or instruction is printed in isolation, e.g. in a debugger
The old behavior can be restored with `-Xllvm -sil-print-types`.
This option is added to many existing test files which check for operand types in their check-lines.
A begin_apply token may be used by operands that do not end the coroutine:
mark_dependence.
We need an API that gives us only the coroutine-ending uses. This blocks
~Escapable accessors.
end_borrow is considered coroutine-ending even though it does not actually
terminate the coroutine.
We cannot simply ask isLifetimeEnding, because end_apply and abort_apply do not
end any lifetime.
When lazy typechecking is enabled, extensions that do not typecheck can make it
to TBDGen, which would crash during its AST walk because `SILSymbolVisitor`
tried to dereference the null nominal type for the extension.
Resolves rdar://139320515.
We currently load it for prespecialization when it wasn't loaded initially.
This causes an inadvertant issue for invertible protocols.
When we don’t have the stdlib loaded initially, we “synthesize” the
invertible protocol from the Builtin module by creating a new `ProtocolDecl*`
and stashing it on the `ASTContext`.
If the stdlib gets loaded later, deserialized stdlib types conform to the deserialized `Escapable` protocol
which has a different `ProtocolDecl *` pointer for `Escapable`.
So queries like `conformsToInvertible` fail because they are using the wrong `ProtocolDecl*`
for `Copyable`/`Escapable` while looking up the ConformanceTable.
In case the control flow ends in a dead-end block there can be begin-borrow instructions which have no corresponding end-borrow uses.
After duplicating such a block, the re-borrow flags cannot be recomputed correctly for inserted phi arguments.
Therefore just disable duplicating such blocks, e.g. in jump-threading.
This API computes the re-borrow flags for guaranteed phis based on the presence of forwarding instructions in the incoming values.
This is not correct in all cases, because optimizations can optimize away forwarding instructions.
Fixes a verifier crash: rdar://139280579
ClangImporter synthesized declarations inherently do not have user written
code. Unfortunately, despite that they are not always marked implicit as they
should be. This was causing a crash when attempting to generate profile
coverage maps for synthesized constructors for imported structs.
I tried marking the constructors implicit, but that had too many knock-on
effects in tests. This more targeted fix unblocks compatibility suite testing
without trying to grapple with the implications of that more fundamental fix.
Resolves rdar://139486938.
