An empty struct without a deinit gets a single bit which is used to
track the struct's liveness. Previously, an empty struct with a deinit
also only got a single bit. Consequently, when discarding the struct
(i.e. dropping the deinit), there was no bit left to represent the
struct. This resulted in a failure to track liveness for the value.
rdar://126863003
A destroy_value of an alloc_box unconditionally destroys the value
within the box. On unreachable paths, such memory may not be
initialized, so it cannot be destroyed unconditionally. Moreover,
destroying values stored in memory is outside the purview of OSSA
lifetime completion.
Previously, the enum representation was fixed to represent the different
cases payloads separately with the unchecked_take_enum_data_addr
instruction consuming all fields but that whose address is obtained.
In a few places, handling for enum deinits was left undone with an
assertion that the enum not have one.
Here, the deinit bit of the enum is shifted to the end. And the
assertions are replaced with handling. Finally, the logic for inserting
destroys after switch_enum_addr instructions is fixed.
Compute, update and handle borrowed-from instruction in various utilities and passes.
Also, used borrowed-from to simplify `gatherBorrowIntroducers` and `gatherEnclosingValues`.
Replace those utilities by `Value.getBorrowIntroducers` and `Value.getEnclosingValues`, which return a lazily computed Sequence of borrowed/enclosing values.
Change FieldSensitive's enum representation to allow distinguishing
among the elements with associated value. Consider
`unchecked_take_enum_data_addr` to consume all other fields than that
taken.
rdar://125113258
An instruction can consume multiple (discontiguous) fields. Use a
SmallBitVector to track the fields consumed by an instruction rather
than a TypeTreeLeafRange.
rdar://125103951
A `try_apply` with indirect out arguments is only a def for those arguments on
the success path. Model this by sinking the def-ness of the instruction into the
success branch of the try_apply, and introducing a new `DeadToLiveEdge` mode for
block liveness which stops propagation of use-before-def conditions into the
block that introduced the def. Fixes rdar://118567869.
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.
We've been building up this exponential explosion of task-creation
builtins because it's not currently possible to overload builtins.
As long as all of the operands are scalar, though, it's pretty easy
to peephole optional injections in IRGen, which means we can at
least just use a single builtin in SIL and then break it apart in
IRGen to decide which options to set.
I also eliminated the metadata argument, which can easily be recreated
from the substitutions. I also added proper verification for the builtin,
which required (1) getting `@Sendable` right more consistently and (2)
updating a bunch of tests checking for things that are not actually
valid, like passing a function that returns an Int directly.
For years, optimizer engineers have been hitting a common bug caused by passes
assuming all SILValues have a parent function only to be surprised by SILUndef.
Generally we see SILUndef not that often so we see this come up later in
testing. This patch eliminates that problem by making SILUndef uniqued at the
function level instead of the module level. This ensures that it makes sense for
SILUndef to have a parent function, eliminating this possibility since we can
define an API to get its parent function.
rdar://123484595
Fill in a missing path for destructuring loadable elements from
address-only tuples in a borrowing context. Enclose projections in their
own separate accesses so that they are analyzed independently by the
move checker.
Moved out of MemoryLocations.h and merged the implementations of <<,
keeping the version from MemoryLocations with its brackets and commas
available via a flag but defaulting the implementation previously in the
header.
Not de-virtualized value type deinits can require metatype in case the deinit needs to be called via the value witness table.
Usually this does not happen because deinits are mandatory de-virtualized. But it can show up if e.g. wrong build options are used.
rdar://122651706
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.
Previously, `visitProductLeafAccessPathNodes` required its caller to
provide both an `AccessPath` `path` and an `SILValue` `address` which
satisfied `path == AccessPath::compute(address)` to force the caller to
handle the case of an invalid `AccessPath`. Now, instead, it computes
the value itself and returns false if it's invalid.
It could be tweaked to also return false if the provided lambda returned
false but that would make the only currently extant callers less
pleasant and also would not be sufficient in the case of caller who
wanted to distinguish between an invalid `AccessPath` and a particular
leaf visit returning false.
A FunctionTest created in Swift source has no persistent storage
address. This results in sporadic crashes when running unit tests.
Fix the FunctionTest registry to store the value of the test.
Eventually, we could probably rig something up with @_rawLayout, but
it makes more sense for FunctionTest to be a value type anyway.
We have no guarantee that the StringRef passed to the registry lives
in the static data segment.
This resulted in memory corruption during bootstrapping, which is
particularly difficult to diagnose and reproduce.
