(old name: CapturePropagation)
The pass is now rewritten in swift which makes the code smaller and simpler.
Compared to the old pass it has two improvements:
* It can constant propagate whole structs (and not only builtin literals). This is important for propagating "real" Swift constants which have a struct type of e.g. `Int`.
* It constant propagates keypaths even if there are other non-constant closure captures which are not propagated. This is something the old pass didn't do.
rdar://151185177
* move some Cloner utilities from ContextCommon.swift directly into Cloner.swift
* add an `cloneRecursively` overload which doesn't require the `customGetCloned` closure argument
* some small cleanups
So far, constant propagated arguments could only be builtin literals.
Now we support arbitrary structs (with constant arguments), e.g. `Int`.
This requires a small addition in the mangling scheme for function specializations.
Also, the de-mangling tree now looks a bit different to support a "tree" of structs and literals.
Restructure the inference logic to allow the same function declaration to
independently annotate or infer different lifetime targets.
For example:
@_lifetime(borrow a)
/* DEFAULT: @_lifetime(b: copy b)
func f(a: A, b: inout B) -> NE
The fact that we prevented this was somewhat accidental and surprising.
This restructuring simplifies the code but also gives us much more control over
the inference logic.
Fixes: rdar://159288750 ("A function cannot have a ~Escapable 'inout' parameter
in addition to other ~Escapable parameters" is not actionable)
Introduce an experimental feature DeferredCodeGen, that defers the
generation of LLVM IR (and therefore object code) for all entities
within an Embedded Swift module unless they have explicitly requested
to not be emitted into the client (e.g., with
`@_neverEmitIntoClient`).
This feature is meant to generalize and subsume
-emit-empty-object-file, relying on lazy emission of entities rather
than abruptly ending the compilation pipeline before emitting any IR.
Part of rdar://158363967.
Otherwise, when multiple workers encounter a diagnostic simultaneously we can encounter races which lead to corrupted diagnostic data or crashes
Resolves rdar://159598539
In anticipation of needing to compute runtime unavailability to determine
whether declarations should be printed in swiftinterfaces, factor out the code
that computes runtime unavailability into a shared utility based on
`DeclAvailabilityConstraints`.
NFC.
This allows diagnostics to be more precise and will also support logic that
allows for special cases for `@available` attributes in exportability checking.
Also fixes a bug where the exportability of `@available` attributes attached to
extensions were diagnosed twice for slightly differing reasons.
This can help work around problems when the names of a C++ declaration
and a Swift declaration would collide, or to temporarily work around
compiler bugs.
rdar://152838988&140802127&158843666
I am going to be adding support to passes for emitting IsolationHistory behind a
flag. As part of this, we need to store the state of the partition that created
the error when the error is emitted. A partition stores heap memory so it makes
sense to make these types noncopyable types so we just move the heap memory
rather than copying it all over the place.
