The `AttrBuilder` API was changed in llvm/llvm-project
d2cc6c2d0c2f8a6e272110416a3fd579ed5a3ac1 to now take a `LLVMContext &`
as part of its constructor. Update uses to pass one in.
`PointerType::getElementType` has been removed entirely as part of the
opaque pointers migration. Update to `getPointerElementType` for now
until we've also migrated.
Thanks to exclusivity checking, inout arguments can be marked noalias.
In the fullness of time, this should be applied in general.
As an incremental step towards marking all such arguments noalias, start
by marking inout arguments of pointer type noalias. Take this
conservative step rather than always applying the attribute to ward
against issues with LLVM's alias analysis.
rdar://76540030
Avoid a reabstraction thunk every time an async let entry point is emitted,
by setting the context abstraction level while we emit the implicit closure.
Adjust some surrounding logic that breaks when we do this:
- When lowering a non-throwing function type against a throwing abstraction
pattern, include the error type in the lowered substituted type. Async
throwing and nonthrowing functions would require another thunk to convert
away the throwingness of the async context, which would defeat the purpose.
- Adjust the code in IRGen that pads the initial context size for `async let`
entry points so that it works when the entry point has not yet emitted, by
marking the async function pointer to be padded later if it isn't defined
yet.
On some Harvard architectures like WebAssembly that allow sliding code
and data address space offsets independently, it's impossible to make
direct relative reference to code from data because the relative offset
between them is not representable.
Use absolute function references instead of relative ones on such targets.
We fixed a bug in the concurrency runtime (rdar://problem/90357994) that would
lead to memory corruption when a new `async let` child task tried to use the
last 16 bytes of the preallocated slab from its parent to seed its own task
allocator. To work around this bug in older OSes that shipped with the bug,
artificially pad the async coroutine context size for any async functions
used as an `async let` entry point, which will prevent the runtime from
going down the path of trying to use the preallocated storage at all.
rdar://90506708
* [cxx-interop] fix std::string::push_back by fixing mapping between clang/swift self/this type for cxx methods
* cleanup
* Fix unit test
* XFail test: operators/member-inline on linux-android
* add `C++` in expandExternalSignatureTypes comment
* Fix rebase
* Fix mapping issue in externalizeArguments
* Improve cxx_interop_ir test regex
Generated code has never actually initialized this field, so we
might as well remove it. Doing so mostly doesn't impact the ABI
since we don't store anything for arguments or results in the
context as part of the normal call sequence. We do need to adjust
some of the hard-coded contexts, however, such as continuation
contexts and the statically-sized context for special runtime
async functions.
In the "next" branch, set_size has been made protected. Instead, users
can use resize_for_overwrite, optionally followed by truncate, to
handle the same use cases more safely.
The special convention currently means three things:
1. There is no async FP symbol for the function. Calls should go directly
to the function symbol, and an async context of fixed static size should be
allocated. This is mandatory for calling runtime-provided async functions.
2. The callee context should be allocated but not initialized. The main
context pointer passed should be the caller's context, and the continuation
function pointer and callee context should be passed as separate arguments.
The function will resume the continuation function pointer with the caller's
context. This is a micro-optimization appropriate for functions that are
expected to frequently return immediately; other functions shouldn't bother.
3. Generic arguments should be suppressed. This is a microoptimization for
certain specific runtime functions where we happen to know that the runtime
already stores the appropriate information internally. Other functions
probably don't want this.
Obviously, these different treatments should be split into different
predicates so that functions can opt in to different subsets of them.
I've also set the code up so that runtime functions can more easily
request a specific static async context size. Previously, it was a
confusingly embedded assumption that the static context size was always
exactly two pointers more than the header.
There are three major changes here:
1. The addition of "SILFunctionTypeRepresentation::CXXMethod".
2. C++ methods are imported with their members *last*. Then the arguments are switched when emitting the IR for an application of the function.
3. Clang decls are now marked as foreign witnesses.
These are all steps towards being able to have C++ protocol conformance.
The functions in llvm-project `AttributeList` have been
renamed/refactored to help remove uses of `AttributeList::*Index`.
Update to use these new functions where possible. There's one use of
`AttrIndex` remaining as `replaceAttributeTypeAtIndex` still takes the
index and there is no `param` equivalent. We could add one locally, but
presumably that will be added eventually.
With PE/COFF, one cannot reference a data symbol directly across the
binary module boundary. Instead, the reference must be indirected
through the Import Address Table (IAT) to allow for position
independence.
When generating a reference to a AsyncFunctionPointer ({i8*, i32}), we
tag the pointer as being indirected by tagging bit 1 (with the
assumption that native alignment will ensure 4/8 byte alignment, freeing
the bottom 2 bits at least for bit-packing). We tweak the
v-table/witness table emission such that all references to the
AsyncFunctionPointer are replaced with the linker synthetic import
symbol with the bit packing:
~~~
.quad __imp_$s1L1CC1yyYaKFTu+1
~~~
rather than
~~~
.quad $s1L1CC1yyYaKFTu
~~~
Upon access of the async function pointer reference, we open-code the
check for the following:
~~~
pointer = (pointer & 1) ? *(void **)(pointer & ~1) : pointer;
~~~
Thanks to @DougGregor for the discussion and the suggestion for the
pointer tagging. Thanks to @aschwaighofer for pointers to the code that
I had missed. Also, thanks to @SeanROlszewski for the original code
sample that led to the reduced test case.
Fixes: SR-15399
If target doesn't support musttail (e.g. WebAssembly), the function
passed to coro.end.async can return control back to the caller.
So the frontend should emit 'ret void' instead of unreachable after the
coro.end.async intrinsic call to allow such situation.
This is to deal with the fact that LLVM's coroutine can't handle instructions
with side-effects well that are inserted before the coro.begin.
rdar://81113950
Rather than using group task options constructed from the Swift parts
of the _Concurrency library and passed through `createAsyncTask`'s
options, introduce a separate builtin that always takes a group. Move
the responsibility for creating the options structure into IRGen, so
we don't need to expose the TaskGroupTaskOptionRecord type in Swift.
Introduce a builtin `createAsyncTask` that maps to `swift_task_create`,
and use that for the non-group task creation operations based on the
task-creation flags. `swift_task_create` and the thin function version
`swift_task_create_f` go through the dynamically-replaceable
`swift_task_create_common`, where all of the task creation logic is
present.
While here, move copying of task locals and the initial scheduling of
the task into `swift_task_create_common`, enabling by separate flags.
introduce new options parameter to all task spawning
[Concurrency] ABI for asynclet start to accept options
[Concurrency] fix unittest usages of changed task creation ABI
[Concurrency] introduce constants for parameter indexes in ownership
[Concurrency] fix test/SILOptimizer/closure_lifetime_fixup_concurrency.swift
Changes the task, taskGroup, asyncLet wait funtion call ABIs.
To reduce code size pass the context parameters and resumption function
as arguments to the wait function.
This means that the suspend point does not need to store parent context
and resumption to the suspend point's context.
```
void swift_task_future_wait_throwing(
OpaqueValue * result,
SWIFT_ASYNC_CONTEXT AsyncContext *callerContext,
AsyncTask *task,
ThrowingTaskFutureWaitContinuationFunction *resume,
AsyncContext *callContext);
```
The runtime passes the caller context to the resume entry point saving
the load of the parent context in the resumption function.
This patch adds a `Metadata *` field to `GroupImpl`. The await entry
pointer no longer pass the metadata pointer and there is a path through
the runtime where the task future is no longer available.
