Created using spr 1.3.6-beta.1

[skip ci]

…ion.

This was reverted because the resolver didn't look as expected in one of
the tests. I believe it had some interaction with #84146. I have now
regenerated it using -target-feature -fp-armv8.

Reverts llvm/llvm-project#84405

In between of passing the precommit tests on github and being merged
some change (perhaps in the AArch64 backend?) landed which resulted
in altering the generated resolver. I will regenerate the tests
perhaps using a less sensitive runline to such changes.

We would like the resolver to be generated eagerly, even if the
versioned function is not called from the current translation
unit. Fixes #81494. It further allows Multi Versioning to work
even if the default target version attribute is omitted from
function declarations.

Previously, annotations were only emitted for function definitions. With
this change annotations are also emitted for declarations. Also,
emitting function annotations is now deferred until the end so that the
most up to date declaration is used which will have any inherited
annotations.

Summary:
This patch reworks how we handle global constructors in OpenMP.
Previously, we emitted individual kernels that were all registered and
called individually. In order to provide more generic support, this
patch moves all handling of this to the target backend and the runtime
plugin. This has the benefit of supporting the GNU extensions for
constructors an destructors, removing a class of failures related to
shared library destruction order, and allows targets other than OpenMP
to use the same support without needing to change the frontend.

This is primarily done by calling kernels that the backend emits to
iterate a list of ctor / dtor functions. For x64, this is automatic and
we get it for free with the standard `dlopen` handling. For AMDGPU, we
emit `amdgcn.device.init` and `amdgcn.device.fini` functions which
handle everything atuomatically and simply need to be called. For NVPTX,
a patch https://github.com/llvm/llvm-project/pull/71549 provides the
kernels to call, but the runtime needs to set up the array manually by
pulling out all the known constructor / destructor functions.

One concession that this patch requires is the change that for GPU
targets in OpenMP offloading we will use `llvm.global_dtors` instead of
using `atexit`. This is because `atexit` is a separate runtime function
that does not mesh well with the handling we're trying to do here. This
should be equivalent in all cases except for cases where we would need
to destruct manually such as:

```
struct S { ~S() { foo(); } };
void foo() {
  static S s;
}
```

However this is broken in many other ways on the GPU, so it is not
regressing any support, simply increasing the scope of what we can
handle.

This changes the handling of ctors / dtors. This patch now outputs a
information message regarding the deprecation if the old format is used.
This will be completely removed in a later release.

Depends on: https://github.com/llvm/llvm-project/pull/71549

We now provide the information about the min/max thread and team count
from to the OMPIRBuilder, no matter what the source was. That means we
unify `thread_limit`, `num_teams`, `num_threads` handling with the
target specific attriutes (`__launch_bounds__` and
`amdgpu_flat_work_group_size`). This is in preparation to pass the
values to the runtime, and to allow the middle-end (OpenMP-opt) to
tighten the values if it seems appropriate. There is no "real" change
after this commit.

This reverts commit c6a33ff49dfb3498dae15c718820ea3d9c19f3cb. Makes
clang segfault.

// clang t.cc
class a;
class c {
 public:
  [[clang::annotate("")]] c(const c *) {}
};
class d {
  d(const c *, a *, a *);
  c e;
};
d::d(const c *f, a *, a *) : e(f) {}

Previously, annotations were only emitted for function definitions. With
this change annotations are also emitted for declarations. Also, emitting
function annotations is now deferred until the end so that the most
up to date declaration is used which will have any inherited annotations.

Differential Revision: https://reviews.llvm.org/D156172/new/

'attribute__((optnone)).

Differential Revision: https://reviews.llvm.org/D151834