We should expose the demangle functionality; It's been widely used by
calling into internal _swift_demangle and instead we should offer a real
API. It's also already used in the Runtime module already when forming
backtraces.
[Previous
discussions](https://forums.swift.org/t/demangle-function/25416/15)
happened between 2019 and 2024, and just never materialized in a
complete implementation and proposal.
Right now, even more tools are in need of this API, as we are building
continious profiling solutions etc, so it is a good time to revisit this
topic.
This PR is roughly based off @Azoy's
https://github.com/swiftlang/swift/pull/25314/files#diff-fd379a721cc9a1c9ef6486eae713e945da842b42170d4d069029a57334371eba
from 2019, however it brings it over to the new Runtime module which is
a great place to put this functionality - even Backtrace had to recently
reinvent calling the demangling infra in this module.
Pending SE review, [proposal
here](https://github.com/swiftlang/swift-evolution/pull/2989).
cc @azoy @al45tair
---------
Co-authored-by: Alastair Houghton <alastair@alastairs-place.net>
Complex equality is encoded in the low bit of the witness table pointer. We need to mask off the low bits when bitcasting to an `any SerialExecutor`.
rdar://164005854
Rather than just looking at top level in the module, start by searching
the type marked as `@main`. This means that a library that provides a
protocol or superclass that the `@main` type can conform to can specify
an executor in a reasonable manner.
We no longer attempt to convert timestamps from the passed-in `Clock`
in order to allow any clock to work with any executor. Instead,
executors that do not recognise a clock should call the `enqueue`
function on that `Clock`, which lets the `Clock` itself decide how
to proceed.
Additionally, rename `SchedulableExecutor` to `SchedulingExecutor`.
rdar://155596073 Task executors execution may not always hop as expected
I'm investigating a fix here as we speak, but disabling the specific piece of the test while we work on it.
Without this, llvm would sometimes wrongly assume there's no indirect
accesses and the optimizations can lead to a runtime crash, by
optimizing away initializing options properly.
Resolves rdar://152548190
With optimizations disabled, the InlineArray initializer uses 512kB of stack space. This can overflow the stack depending on exactly how things are set up. Reduce stack usage by manually allocating memory for the array and initializing it as a pointer to Int.
rdar://152420308
statusCompletePendingReadyWaiting(), offer(), and poll() did a one-off compare_exchange_strong which could fail if the group was concurrently cancelled. Put these into loops so that they are retried when needed.
DiscardingTaskGroup creation passed the group result type as the task result type. waitAll() would then use the group result type when collecting task results. Since the task result type is always Void in this case, this would overflow the result buffer if the group result type was larger. This often works as it writes into the free space of the task allocator, but can crash if it happens to be at the end of a page or the group result type is particularly large.
rdar://151663730
We deallocate an instruction's packs at points where no further
control flow path uses the value. In the case of an alloc_stack,
this will be right after the dealloc_stack. Thus, if alloc_stack
allocates some packs to build type metadata for a tuple type
that contains a pack, and then proceeds to allocate a value
large enough to hold the tuple, we will free the second allocation
first, before we free the pack, as expected.
However, after stack allocating the value, alloc_stack does
some further work to emit debug info. This could result in
emission of additional metadata packs.
Split up the debug info emission into two parts; the first we do
before we perform the stack allocation, the rest we do after.
- Fixes https://github.com/swiftlang/swift/issues/67702.
- Fixes rdar://problem/141363236.
Custom main and global executors work hasn't passed Swift Evolution yet,
so we need to avoid leaking it as API until it does.
To that end, underscore all the things.
rdar://151147606
