Exception handling records are unlinked on function return. However, if
there is a musttail call before the return, that's the de-facto point of
termination and the unlinking instructions must be inserted *before*
that.

Fixes #119255

At the moment Windows 32 bit SEH state stores are only emitted for
throwing calls.

Windows 32 bit SEH state stores should also be emitted before SEH scope
begin and before SEH scope end.
An invalid inline memory access would otherwise not trigger unwinding,
in combination with /EHa.

This fixes #90946

This fixes issue #116583

When inalloca calls are inlined the static stack pointer saving prolog
of X86WinEHState breaks due to dynamic allocas.
In this case we need to update the saved esp for every inalloca and for
every stackrestore also related to inalloca.

Fixes https://github.com/llvm/llvm-project/issues/105813 and
https://github.com/llvm/llvm-project/issues/106915.
Adds a check for the end of the iterator, which can be a sentinel. 
The issue was introduced in
https://github.com/llvm/llvm-project/commit/0efe111365ae176671e01252d24028047d807a84
from what I can see, so along with the introduction of /EHa support.

Forgot to rename `winehprepare` for legacy pass when port this pass to
new passmanager.

This is a follow-up to b71edfaa4ec3c998aadb35255ce2f60bba2940b0
since I forgot the lit.local.cfg files in that one.

Reformatting is done with `black`.

If you end up having problems merging this commit because you
have made changes to a python file, the best way to handle that
is to run git checkout --ours <yourfile> and then reformat it
with black.

If you run into any problems, post to discourse about it and
we will try to help.

RFC Thread below:

https://discourse.llvm.org/t/rfc-document-and-standardize-python-code-style

Reviewed By: barannikov88, kwk

Differential Revision: https://reviews.llvm.org/D150762

IR is now always parsed in opaque pointer mode, unless
-opaque-pointers=0 is explicitly given. There is no automatic
detection of typed pointers anymore.

The -opaque-pointers=0 option is added to any remaining IR tests
that haven't been migrated yet.

Differential Revision: https://reviews.llvm.org/D141912