An `AvailabilityContext` represents an abstract version range in which
something is available. In the future, these version ranges may not necessarily
always correspond to operating system version ranges.
NFC.
In order for availability checks in iOS apps to be evaluated correctly when
running on macOS, the application binary must call a copy of
`_stdlib_isOSVersionAtLeast_AEIC()` that was emitted into the app, instead of
calling the `_stdlib_isOSVersionAtLeast()` function provided by the standard
library. This is because the call to the underlying compiler-rt function
`__isPlatformVersionAtLeast()` must be given the correct platform identifier
argument; if the call is not emitted into the client, then the macOS platform
identifier is used and the iOS version number will be mistakenly interpreted as
a macOS version number at runtime.
The `_stdlib_isOSVersionAtLeast()` function in the standard library is marked
`@_transparent` on iOS so that its call to `_stdlib_isOSVersionAtLeast_AEIC()`
is always inlined into the client. This works for the code generated by normal
`if #available` checks, but for the `@backDeployed` function thunks, the calls
to `_stdlib_isOSVersionAtLeast()` were not being inlined and that was causing
calls to `@backDeployed` functions to crash in iOS apps running on macOS since
their availability checks were being misevaluated.
The SIL optimizer has a heuristic which inhibits mandatory inlining in
functions that are classified as thunks, in order to save code size. This
heuristic needs to be relaxed in `@backDeployed` thunks, so that mandatory
inlining of `_stdlib_isOSVersionAtLeast()` can behave as expected. The change
should be safe since the only `@_transparent` function a `@backDeployed` thunk
is ever expected to call is `_stdlib_isOSVersionAtLeast()`.
Resolves rdar://134793410.
This corresponds to the parameter-passing convention of the Itanium C++
ABI, in which the argument is passed indirectly and possibly modified,
but not destroyed, by the callee.
@in_cxx is handled the same way as @in in callers and @in_guaranteed in
callees. OwnershipModelEliminator emits the call to destroy_addr that is
needed to destroy the argument in the caller.
rdar://122707697
- While an opaque borrow access occurs to part of a value, the entire scope of
the access needs to be treated as a liveness range, so add the `EndAccess`es
to the liveness range.
- The SIL verifier may crash the compiler on SILGen-generated code when the
developer's source contains consume-during-borrow code patterns. Allow
`load_borrow` instructions to be marked `[unchecked]`, which suppresses
verifier checks until the move checker runs and gets a chance to properly
diagnose these errors.
Fixes rdar://124360175.
Although I don't plan to bring over new assertions wholesale
into the current qualification branch, it's entirely possible
that various minor changes in main will use the new assertions;
having this basic support in the release branch will simplify that.
(This is why I'm adding the includes as a separate pass from
rewriting the individual assertions)
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.
[serialized_for_package] if Package CMO is enabled. The latter kind
allows a function to be serialized even if it contains loadable types,
if Package CMO is enabled. Renamed IsSerialized_t as SerializedKind_t.
The tri-state serialization kind requires validating inlinability
depending on the serialization kinds of callee vs caller; e.g. if the
callee is [serialized_for_package], the caller must be _not_ [serialized].
Renamed `hasValidLinkageForFragileInline` as `canBeInlinedIntoCaller`
that takes in its caller's SerializedKind as an argument. Another argument
`assumeFragileCaller` is also added to ensure that the calle sites of
this function know the caller is serialized unless it's called for SIL
inlining optimization passes.
The [serialized_for_package] attribute is allowed for SIL function, global var,
v-table, and witness-table.
Resolves rdar://128406520
package-wide resilience domain if Package CMO is enabled.
The purpose of the attribute includes:
- Indicates that certain types such as loadable types are
allowed in serialized functions in resiliently built module
if the optimization is enabled, which are otherwise disallowed.
- Used during SIL deserialization to determine whether such
functions are allowed.
- Used to determine if a callee can be inlined into a caller
that's serialized without package-cmo, e.g. with an explicit
annotation like @inlinable, where the callee was serialized
due to package-cmo.
Resolves rdar://127870822
getVarInfo() now always returns a variable with a location and scope.
To opt out of this change, getVarInfo(false) returns an incomplete variable.
This can be used to work around bugs, but should only really be used for
printing.
The complete var info will also contain the type, except for debug_values,
as its type depends on another instruction, which may be inconsistent if
called mid-pass.
All locations in debug variables are now also stripped of flags, to avoid
issues when comparing or hashing debug variables.
* Allow normal function results of @yield_once coroutines
* Address review comments
* Workaround LLVM coroutine codegen problem: it assumes that unwind path never returns.
This is not true to Swift coroutines as unwind path should end with error result.
LLVM is presumably moving towards `std::string_view` -
`StringRef::startswith` is deprecated on tip. `SmallString::startswith`
was just renamed there (maybe with some small deprecation inbetween, but
if so, we've missed it).
The `SmallString::startswith` references were moved to
`.str().starts_with()`, rather than adding the `starts_with` on
`stable/20230725` as we only had a few of them. Open to switching that
over if anyone feels strongly though.
Renamed "getUsesMoveableValueDebugInfo" to "usesMoveableValueDebugInfo".
Clarifies the predicate from "does the receiver have the
usesMoveableValueDebugInfo field set?" to "does the receiver use moveable
value debug info?".
We want to preserve the borrow scope during switch dispatch so that move-only
checking doesn't try to analyze destructures or consumes out of it. SILGen
should mark anywhere that's a potential possibility with its own marker so that
it gets borrow checked independently.
Relax some existing pattern matches and add some unhandled instructions to the
walkers so that borrowing switches over address-only enums are properly analyzed
for incorrect consumption. Add a `[strict]` flag to `mark_unresolved_move_only_value`
to indicate a borrow access that should remain a borrow access even if the subject
is later stack-promoted from a box.
