The problem was in calling GetLoadAddress on a value in the error state,
where `ValueObject::GetLoadAddress` could end up accessing the
uninitialized "address type" by-ref return value from `GetAddressOf`.
This probably happened because each function expected the other to
initialize it.

We can guarantee initialization by turning this into a proper return
value.

I've added a test, but it only (reliably) crashes if lldb is built with
ubsan.

We're reading from the object's vtable to determine the pointer to the
full object. The vtable is normally in the "rodata" section of the
executable, which is often not included in the core file because it's
not supposed to change and the debugger can extrapolate its contents
from the executable file. We weren't doing that.

This patch changes the read operation to use the target class (which
falls back onto the executable module as expected) and adds the missing
ReadSignedIntegerFromMemory API. The fix is tested by creating a core
(minidump) file which deliberately omits the vtable pointer.

This PR fixes LLDB stepping out, rather than stepping through a C++
thunk. The implementation is based on, and upstreams, the support for
runtime thunks in the Swift fork.

Fixes #43413

…uffer

ValueObjectDynamicValue::UpdateValue() assumes that the dynamic type
found by GetDynamicTypeAndAddress() would return an address in the
inferior. This commit makes it so it can deal with being passed a host
address instead.

This is needed downstream by the Swift fork.

rdar://143357274

Many uses of SC::GetAddressRange were not interested in the range, but
in the address of the function/symbol contained inside the symbol
context. They were getting that by calling the GetBaseAddress on the
returned range, which worked well enough so far, but isn't compatible
with discontinuous functions, whose address (entry point) may not be the
lowest address in the range.

To resolve this problem, this PR creates a new function whose purpose is
return the address of the function or symbol inside the symbol context.
It also changes all of the callers of GetAddressRange which do not
actually care about the range to call this function instead.

Lots of code around LLDB was directly accessing the target's section
load list. This NFC patch makes the section load list private so the
Target class can access it, but everyone else now uses accessor
functions. This allows us to control the resolving of addresses and will
allow for functionality in LLDB which can lazily resolve addresses in
JIT plug-ins with a future patch.

ValueObject is part of lldbCore for historical reasons, but conceptually
it deserves to be its own library. This does introduce a (link-time) circular
dependency between lldbCore and lldbValueObject, which is unfortunate
but probably unavoidable because so many things in LLDB rely on
ValueObject. We already have cycles and these libraries are never built
as dylibs so while this doesn't improve the situation, it also doesn't
make things worse.

The header includes were updated with the following command:

```
find . -type f -exec sed -i.bak "s%include \"lldb/Core/ValueObject%include \"lldb/ValueObject/ValueObject%" '{}' \;
```

This commit changes the libc++ frame recognizer to hide implementation
details of libc++ more aggressively. The applied heuristic is rather
straightforward: We consider every function name starting with `__` as
an implementation detail.

This works pretty neatly for `std::invoke`, `std::function`,
`std::sort`, `std::map::emplace` and many others. Also, this should
align quite nicely with libc++'s general coding convention of using the
`__` for their implementation details, thereby keeping the future
maintenance effort low.

However, this heuristic by itself does not work in 100% of the cases:
E.g., `std::ranges::sort` is not a function, but an object with an
overloaded `operator()`, which means that there is no actual call
`std::ranges::sort` in the call stack. Instead, there is a
`std::ranges::__sort::operator()` call. To make sure that we don't hide
this stack frame, we never hide the frame which represents the entry
point from user code into libc++ code

This patch extends TypeQuery matching to support anonymous namespaces. A
new flag is added to control the behavior. In the "strict" mode, the
query must match the type exactly -- all anonymous namespaces included.
The dynamic type resolver in the itanium abi (the motivating use case
for this) uses this flag, as it queries using the name from the
demangles, which includes anonymous namespaces.

This ensures we don't confuse a type with a same-named type in an
anonymous namespace. However, this does *not* ensure we don't confuse
two types in anonymous namespacs (in different CUs). To resolve this, we
would need to use a completely different lookup algorithm, which
probably also requires a DWARF extension.

In the "lax" mode (the default), the anonymous namespaces in the query
are optional, and this allows one search for the type using the usual
language rules (`::A` matches `::(anonymous namespace)::A`).

This patch also changes the type context computation algorithm in
DWARFDIE, so that it includes anonymous namespace information. This
causes a slight change in behavior: the algorithm previously stopped
computing the context after encountering an anonymous namespace, which
caused the outer namespaces to be ignored. This meant that a type like
`NS::(anonymous namespace)::A` would be (incorrectly) recognized as
`::A`). This can cause code depending on the old behavior to misbehave.
The fix is to specify all the enclosing namespaces in the query, or use
a non-exact match.

With this commit, we also hide the implementation details of
`std::invoke`. To do so, the `LibCXXFrameRecognizer` got a couple more
regular expressions.

The regular expression passed into `AddRecognizer` became problematic,
as it was evaluated on the demangled name. Those names also included
result types for C++ symbols. For `std::__invoke` the return type is a
huge `decltype(...)`, making the regular expresison really hard to
write.

Instead, I added support to `AddRecognizer` for matching on the
demangled names without result type and argument types.

By hiding the implementation details of `invoke`, also the back traces
for `std::function` become even nicer, because `std::function` is using
`__invoke` internally.

Co-authored-by: Adrian Prantl <aprantl@apple.com>