It indicates that the value's lifetime continues to at least this point.
The boundary formed by all consuming uses together with these
instructions will encompass all uses of the value.
Don't treat StoreBorrow addresses as unknown bases. While they are never the base of a formal access, they are returned
as the AccessBase when querying the enclosing scope of an address.
Add PartialApplyInst.hasNoescapeCapture
Add PartialApplyInst.mayEscape
Refactor DiagnoseInvalidEscapingCaptures. This may change functionality because tuples containing a noescape closure are now correctly recognized. Although I'm not sure such tupes can ever be captured directly.
To make the ScopedInstruction abstraction useful and formalize to use-points of scoped operations.
This is specifically for scoped operations that use their operands up to the end of their scope.
This is not for the many instructions that introduce scoped lifetimes. Allocations are not considered scoped
operations. Every owned value has a scoped lifetime just like an allocation, but the scope-ending instructions are not
considered use points.
These instructions carry lifetime dependence from a single operand to a single result. They are not forwarding
instructions because we use them to indicate the boundaries of a forwarded lifetime.
* add ForwardingInstruction conformances to missing forwarding instruction classes
* move all the forwarding instruction conformance definitions into ForwardingInstructions.swift
* remove the default implementations of the requirements, so that every instruction needs to specify them
In preparation for inserting mark_dependence instructions for lifetime
dependencies early, immediately after SILGen. That will simplify the
implementation of borrowed arguments.
Marking them unresolved is needed to make OSSA verification
conservative until lifetime dependence diagnostics runs.
Optionally, the dependency to the initialization of the global can be specified with a dependency token `depends_on <token>`.
This is usually a `builtin "once"` which calls the initializer for the global variable.
The dependent 'value' may be marked 'nonescaping', which guarantees that the
lifetime dependence is statically enforceable. In this case, the compiler
must be able to follow all values forwarded from the dependent 'value', and
recognize all final (non-forwarded, non-escaping) use points. This implies
that `findPointerEscape` is false. A diagnostic pass checks that the
incoming SIL to verify that these use points are all initially within the
'base' lifetime. Regular 'mark_dependence' semantics ensure that
optimizations cannot violate the lifetime dependence after diagnostics.
Layers:
- FunctionConvention: AST FunctionType: results, parameters
- ArgumentConventions: SIL function arguments
- ApplyOperandConventions: applied operands
The meaning of an integer index is determined by the collection
type. All the mapping between the various indices (results,
parameters, SIL argument, applied arguments) is restricted to the
collection type that owns that mapping. Remove the concept of a
"caller argument index".
* `alloc_vector`: allocates an uninitialized vector of elements on the stack or in a statically initialized global
* `vector`: creates an initialized vector in a statically initialized global
`BorrowIntroducingInstruction` is a protocol to which all instructions conform which start a borrow-scope which must be ended by `EndBorrowInst` instructions: `begin_borrow`, `load_borrow` and `store_borrow`
