Only record an outgoingArgument access when the current allocation is an
outgoing argument and the function exiting instruction is ReturnInst.
This avoids invalid SIL where we attempt to extend end_access up to an `unwind` but
fail to actually materialize that end_access.
Don't always consider an inout_aliasable argument to have
escaped. AccessEnforcementSelection has already done that analysis and left
begin_access [dynamic] artifacts if the argument has escaped in any meaningful
way. Use that information to
Essential for supporting autoclosures that call mutating methods on span-like
things. Such as UTF8Span.UnicodeScalarIterator.skipForward():
e.g. while numSkipped < n && skipForward() != 0 { ... }
Define LocalAccessInfo._isFullyAssigned to mean that the access does not read
the incoming value. Then treat any assignment that isn't full as a potential read.
Calling `cloneRecursively` from `SpecializationInfo.cloneClosures`
requires the callee having ownership info. Otherwise, the cloner uses
`recordFoldedValue` instead of `recordClonedInstruction`, and
`postProcess` hook is not called, which leads to an assertion failure in
`BridgedClonerImpl::cloneInst`.
* remove `filterUsers(ofType:)`, because it's a duplication of `users(ofType:)`
* rename `filterUses(ofType:)` -> `filter(usersOfType:)`
* rename `ignoreUses(ofType:)` -> `ignore(usersOfType:)`
* rename `getSingleUser` -> `singleUser`
* implement `singleUse` with `Sequence.singleElement`
* implement `ignoreDebugUses` with `ignore(usersOfType:)`
This is a follow-up of eb1d5f484c.
In case of a non-copyable type the final destroy (or take) of a stack location can be missing if the value has only trivial fields.
The optimization inserted a `destroy_addr` in this case although it wasn't there before.
Beside fixing this problem I also refactored the code a bit to make it more readable.
This is done by splitting the `begin_borrow` of the whole struct into individual borrows of the fields (for trivial fields no borrow is needed).
And then sinking the `struct` to it's consuming use(s).
```
%3 = struct $S(%nonTrivialField, %trivialField) // owned
...
%4 = begin_borrow %3
%5 = struct_extract %4, #S.nonTrivialField
%6 = struct_extract %4, #S.trivialField
use %5, %6
end_borrow %4
...
end_of_lifetime %3
```
->
```
...
%5 = begin_borrow %nonTrivialField
use %5, %trivialField
end_borrow %5
...
%3 = struct $S(%nonTrivialField, %trivialField)
end_of_lifetime %3
```
This optimization is important for Array code where the Array buffer is constantly wrapped into structs and then extracted again to access the buffer.
Handle storing to a mutable property implemented as unsafeMutableAddress. In
SIL, the stored address comes from pointer_to_address. Recognize the addressor
pattern and handle the store as if it writes to a regular property of 'self'.
Required for UnsafePointer<~Escapable>.pointee.
Beside supporting OSSA, this change significantly simplifies the pass.
The main change is that instead of starting at a closure (e.g. `partial_apply`) and finding all call sites, we now start at a call site and look for closures for all arguments. This makes a lot of things much simpler, e.g. not so many intermediate data structures are required to track all the states.
I needed to remove the 3 unit tests because the things those tests were testing are not there anymore. However, the pass is tested with a lot of sil tests (and I added quite a few), which should give good test coverage.
The old ClosureSpecializer pass is still kept in place, because at that point in the pipeline we don't have OSSA, yet. Once we have that, we can replace the old pass withe the new one.
However, the autodiff closure specializer already runs in the OSSA pipeline and there the new changes take effect.
Lifetime diagnostics may report an error within an implicit initializer or
accessor. The source location is misleading in these cases and causes much
consternation.
When a non-Escapable value depends on the address of a trivial value, we use a
special computeAddressableRange analysis to compute the trivial value's
scope. Extend that analysis to include unreachable paths.
Fixes this pattern:
inlineStorage.span.withUnsafeBytes
where inlineStorage is a trivial type defined in the user module. This
does not reproduce directly with InlineArray, but it is a problem for
user modules that have their own trivial wrapper around an InlineArray.
Fixes rdar://161630684 (Incorrect diagnostic: lifetime-dependent value escapes its scope)
Storing a trivial enum case in a non-trivial enum must be treated like a non-trivial init or assign, e.g.
```
%1 = enum $Optional<String>, #Optional.none!enumelt
store %1 to [trivial] %0 // <- cannot delete this store!
store %2 to [assign] %0
```
