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

Git repository change summary for qt/clang/llvm
Pushed by mirror-service into branch 'upstream/release/23.x'.
Changed from 5aa15abead01fef21fee4706aa01f39e8ac18829 to 47e2df730a099583f16fc6fe64f0d2ffc5b7a16a
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 66ba3bdaa25418fed2e74cd39576f236498bf289 by llvmbot (on behalf of hev) on 17/07/2026 at 02:34..
[LoongArch] Fix invalid VEXTH combines for unsupported type extensions (#209725)

`performEXTENDCombine` could form `VEXTH`/`VEXTH_U` nodes for
unsupported type combinations, such as extending `v8i8` to `v8i32` or
`v2i64` to `v2i128`. These illegal nodes would later reach instruction
selection and trigger backend failures:

* `Cannot select: LoongArchISD::VEXTH`
* `Don't know how to legalize this operation`

Prevent these combines from firing by verifying that the destination
type is legal and has exactly twice the total bit width of the source
before forming a `VEXTH`/`VEXTH_U` node.

Apply the same checks to `performSHLCombine` for consistency.

Fixes
https://github.com/llvm/llvm-project/pull/207316#issuecomment-4978234865
Fixes
https://github.com/llvm/llvm-project/pull/207316#issuecomment-4979233899

(cherry picked from commit 4a75259134c72d8be7fa3ea36c9dc7bfc02640ac)
https://invent.kde.org/qt/clang/llvm/-/commit/66ba3bdaa25418fed2e74cd39576f236498bf289

Git commit 47e2df730a099583f16fc6fe64f0d2ffc5b7a16a by Douglas Yung (on behalf of Daniel Kiss) on 17/07/2026 at 07:48..
[AArch64][COFF] Branch-protection=standard/pac-ret means "b-key" on Windows (#203989)

On AArch64 Windows the `B-key` is the only supported key for userspace,
let's make "standard" and "pac-ret" options generate "b-key".

Fixes: #203852
(cherry picked from commit 68f703f3e58a52c41b39dfc654a675560b6c5614)
https://invent.kde.org/qt/clang/llvm/-/commit/47e2df730a099583f16fc6fe64f0d2ffc5b7a16a