[qt/clang/llvm]: Summary of bulk changes made

Git repository change summary for qt/clang/llvm
Pushed by mirror-service into branch 'upstream/users/gandhi56/sandbox-vectorizer/fix-topdown-trimschedule'.
Changed from 6da4586b452b2e76ac3feb8e8884cf4ab9be20bb to 08efe1c283f6614606eab7395f8db790e81c10f4
Acknowledgement was received that this change introduces only existing code that has been pushed to another public open source repository.

This change contains the following new commits:

Git commit b11881e5daa280d322127d4c51dcf472dbcc1dd5 by GitHub (on behalf of Aiden Grossman) on 21/07/2026 at 23:21..
[BranchFolding] Fold away subsequent identical branches

If we have a BB that has a single conditional branch instruction it that
is identical to the previous block's branch instruction, we can delete
the BB as it is redundant.

This doesn't directly impact performance as such instructions are never
executed, but this can help decrease code size which can help with
overall icache pressure (though likely only slightly). The biggest
impact would probably be fitting more instructions into a single cache
line. This is probably almost a no-op with PLO but definitely doesn't
hurt.

Fixes #202763.

Reviewers: RKSimon, arsenm, krzysz00, topperc, lei137

Pull Request: https://github.com/llvm/llvm-project/pull/203110
https://invent.kde.org/qt/clang/llvm/-/commit/b11881e5daa280d322127d4c51dcf472dbcc1dd5

Git commit 8b9cce358bef26ae4cb9275dd6a43f903bafbaa0 by GitHub (on behalf of jimingham) on 21/07/2026 at 23:31..
Make result variables obey their dynamic values in subsequent expressions

This is a resubmit of the original patch: 6344e3aa8106dfdfb30cac36c8ca02bc4c52ce24:

Make result variables obey their dynamic values in subsequent
expressions (#168611)

When I originally submitted this, it caused intermittent flakey failures
on systems I didn't have access to, and I didn't have time to sort them
out, so I reverted the patch. I'm resubmitting this so I can run the
bots on it a few rounds to see if I can reproduce and diagnose those
intermittent failures.

Here's the commit log from the original submission describing the
change:

When you run an expression and the result has a dynamic type that is
different from the expression's static result type, we print the result
variable using the dynamic type, but at present when you use the result
variable in an expression later on, we only give you access to the
static type. For instance:

```
(lldb) expr MakeADerivedReportABase()
(Derived *) $0 = 0x00000001007e93e0
(lldb) expr $0->method_from_derived()
                ^
                error: no member named 'method_from_derived' in 'Base'
(lldb)

```

The static return type of that function is `Base *`, but we printed that
the result was a `Derived *` and then only used the `Base *` part of it
in subsequent expressions. That's not very helpful, and forces you to
guess and then cast the result types to their dynamic type in order to
be able to access the full type you were returned, which is
inconvenient.

This patch makes lldb retain the dynamic type of the result variable
(and ditto for persistent result variables).

It also adds more testing of expression result variables with various
types of dynamic values, to ensure we can access both the ivars and
methods of the type we print the result as.
https://invent.kde.org/qt/clang/llvm/-/commit/8b9cce358bef26ae4cb9275dd6a43f903bafbaa0

Git commit 08efe1c283f6614606eab7395f8db790e81c10f4 by Anshil Gandhi on 21/07/2026 at 23:42..
[SBVec] Refill ready list during topdown scheduling

Visit nodes which are ready according to the direction of scheduling.
https://invent.kde.org/qt/clang/llvm/-/commit/08efe1c283f6614606eab7395f8db790e81c10f4