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

Git repository change summary for qt/clang/llvm-project
Pushed by mirror-service into branch 'upstream/release/23.x'.
Changed from fdf8b84c79164e6f8bcbabcf7f6f79cbe4e20b1f to 6278eba367e2f0eebfdc31ab8b29a02ca27e6f15
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 26555971ce6a203b7ea75f1526bcdfa17f34a037 by Douglas Yung (on behalf of Tom Stellard) on 07/08/2026 at 08:22..
workflows/llvm-abi-tests: Cache the baseline abi (#211968)

This way we don't need to recompute it for every workflow.

(cherry picked from commit 09734937d37ca9c8e8c9cdaa55d00339068922c3)
https://invent.kde.org/qt/clang/llvm-project/-/commit/26555971ce6a203b7ea75f1526bcdfa17f34a037

Git commit 92664717c4d55f6bbf6a464c8591247debfde852 by Douglas Yung (on behalf of Jean-Didier PAILLEUX) on 07/08/2026 at 08:23..
[flang][MIF] Fix undef reference to a coarray_handle in mif.dealloc_coarray #193157 (#213890)

This PR fixes the behavior reported in issue #193157. The coarray_handle
was only defined if a call to mif.alloc_coarray was present.
If a call to mif.dealloc_coarray was encountered without a prior call to
mif.alloc_coarray, then the coarray_handle was missing, and therefore
llvm.address_of pointed to a non-existent address, which is not allowed.
We now define a coarray_handle that has not been allocated by PRIF for
each coarray variables.

(cherry picked from commit a9426776e78a89dec776c34efdb7725de591d878)
https://invent.kde.org/qt/clang/llvm-project/-/commit/92664717c4d55f6bbf6a464c8591247debfde852

Git commit b7cde8f7301aea6b14ae8c71fb81344a87531402 by Douglas Yung (on behalf of Trevor Gross) on 07/08/2026 at 08:24..
[compiler-rt] Disable executable stack on `aeabi_u{read,write}*.S` (#214465)

These were missing `NO_EXEC_STACK_DIRECTIVE` to add `.note.GNU-stack`;
without it, a binary including any of these files will have the stack
marked executable. Add the directive here, matching other similar files.

Symtab diff before:

$ clang compiler-rt/lib/builtins/arm/aeabi_uread4.S
--target=arm-unknown-linux-gnueabi -c
    $ llvm-readelf aeabi_uread4.o -S
    There are 5 section headers, starting at offset 0xe4:

    Section Headers:
[Nr] Name Type Address Off Size ES Flg Lk Inf Al
[ 0] NULL 00000000 000000 000000 00 0 0 0
[ 1] .strtab STRTAB 00000000 0000a8 000039 00 0 0 1
[ 2] .text PROGBITS 00000000 000034 000020 00 AX 0 0 4
[ 3] .ARM.attributes ARM_ATTRIBUTES 00000000 000054 000022 00 0 0 1
[ 4] .symtab SYMTAB 00000000 000078 000030 10 1 2 4

After:

$ clang compiler-rt/lib/builtins/arm/aeabi_uread4.S
--target=arm-unknown-linux-gnueabi -c
    $ llvm-readelf aeabi_uread4.o -S
    There are 6 section headers, starting at offset 0xf4:

    Section Headers:
[Nr] Name Type Address Off Size ES Flg Lk Inf Al
[ 0] NULL 00000000 000000 000000 00 0 0 0
[ 1] .strtab STRTAB 00000000 0000a8 000049 00 0 0 1
[ 2] .text PROGBITS 00000000 000034 000020 00 AX 0 0 4
[ 3] .note.GNU-stack PROGBITS 00000000 000054 000000 00 0 0 1
[ 4] .ARM.attributes ARM_ATTRIBUTES 00000000 000054 000022 00 0 0 1
[ 5] .symtab SYMTAB 00000000 000078 000030 10 1 2 4

Fixes: 39413af931a7 ("[Compiler-rt] Implement AEABI Unaligned Read/Write
       Helpers in compiler-rt (#167913)")
(cherry picked from commit 849c51e082b0958524246a0a880f46d468a55147)
https://invent.kde.org/qt/clang/llvm-project/-/commit/b7cde8f7301aea6b14ae8c71fb81344a87531402

Git commit e134dc02945a512d905b8e55ca875252a1dc02b6 by Douglas Yung (on behalf of Jacek Caban) on 07/08/2026 at 08:24..
[LLD][COFF] Emit ARM64X relocations for TLS directory (#213529)

The current behavior of merging EC and native chunks to have a single
TLS directory for both views matches the MSVC linker, but it has its
shortcomings. In addition to merging, that solution requires all TLS
callbacks to use -arm64xsameaddress, leaving it to the CRT to handle. If
the appropriate EC object files are not pulled in by linked EC code and
thus never have a chance to mark the callback with -arm64xsameaddress,
this may lead to an invalid image that crashes at runtime.

This patch avoids the entire problem by using entirely separate TLS
directories for EC and native views along with the standard ARM64X
dynamic relocation mechanism. Since callback lists are now separate, a
missing -arm64xsameaddress is no longer a problem.

Also, mingw-w64-crt currently doesn't mark its TLS callbacks with
-arm64xsameaddress. That could be changed if needed, but with this
change, it is no longer necessary.

(cherry picked from commit 65e92e073539c3fe3523256c4fba35ac1dedcb92)
https://invent.kde.org/qt/clang/llvm-project/-/commit/e134dc02945a512d905b8e55ca875252a1dc02b6

Git commit 22149f3448a6fc9163e46fecfa01c1c26f66da9b by Douglas Yung (on behalf of Jean-Didier PAILLEUX) on 07/08/2026 at 08:25..
[flang][MIF] Fix team_type usage in all MIF operations #205953 (#214207)

This PR resolves the issue #205953. Its purpose is to correct the use of
`team_type` by lowering it to Addr rather than to Box.

(cherry picked from commit 0563f0d88d8314edcde7deab465759a84696e894)
https://invent.kde.org/qt/clang/llvm-project/-/commit/22149f3448a6fc9163e46fecfa01c1c26f66da9b

Git commit 6278eba367e2f0eebfdc31ab8b29a02ca27e6f15 by Douglas Yung (on behalf of Mingjie Xu) on 07/08/2026 at 09:00..
Revert "[SCEV] Speed up forgetLoop by avoiding def-use walk for loop-header PHIs" (#212485)

Reverts https://github.com/llvm/llvm-project/pull/201572
Multiple miscompilations are reported, see
https://github.com/llvm/llvm-project/issues/207744,
https://github.com/llvm/llvm-project/issues/212027

That commit made forgetLoop() rely on LoopUsers[L] and stop walking the
def-use chain of the loop-header PHIs. This is insufficient, because
some cached data is derived from the underlying IR of SCEVUnknown, it is
not reachable from LoopUsers[L].
After that commit, forgetLoop() no longer invalidated them, so stale
UnsignedRanges / SignedRanges, ConstantMultipleCache, ValuesAtScopes
cause miscompilations.

(cherry picked from commit 1c0eda0d2371a6a755f90299892a7b89dc917442)
https://invent.kde.org/qt/clang/llvm-project/-/commit/6278eba367e2f0eebfdc31ab8b29a02ca27e6f15