[clang] [llvm] Reland "[X86][AMX] Support AMX-AVX512" (PR #115581)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-aarch64-sve-vls` running on `linaro-g3-04` while building `clang,llvm` at step 7 "ninja check 1".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/143/builds/3324

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 7 (ninja check 1) failure: stage 1 checked (failure)
******************** TEST 'AddressSanitizer-Unit :: ./Asan-aarch64-inline-Dynamic-Test/66/95' FAILED ********************
Script(shard):
--
GTEST_OUTPUT=json:/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/stage1/runtimes/runtimes-bins/compiler-rt/lib/asan/tests/AARCH64LinuxDynamicConfig/./Asan-aarch64-inline-Dynamic-Test-AddressSanitizer-Unit-4088106-66-95.json GTEST_SHUFFLE=0 GTEST_TOTAL_SHARDS=95 GTEST_SHARD_INDEX=66 /home/tcwg-buildbot/worker/clang-aarch64-sve-vls/stage1/runtimes/runtimes-bins/compiler-rt/lib/asan/tests/AARCH64LinuxDynamicConfig/./Asan-aarch64-inline-Dynamic-Test
--

Note: This is test shard 67 of 95.
[==========] Running 1 test from 1 test suite.
[----------] Global test environment set-up.
[----------] 1 test from AddressSanitizer
[ RUN      ] AddressSanitizer.OOB_int

--
exit: -6
--
shard JSON output does not exist: /home/tcwg-buildbot/worker/clang-aarch64-sve-vls/stage1/runtimes/runtimes-bins/compiler-rt/lib/asan/tests/AARCH64LinuxDynamicConfig/./Asan-aarch64-inline-Dynamic-Test-AddressSanitizer-Unit-4088106-66-95.json
********************

Step 13 (test-suite) failure: 1200 seconds without output running [b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/test/sandbox/bin/python', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/test/sandbox/bin/lnt', b'runtest', b'test-suite', b'--no-timestamp', b'--sandbox', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/test/sandbox', b'--test-suite', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/test/test-suite', b'--cc', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/stage1.install/bin/clang', b'--cxx', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/stage1.install/bin/clang++', b'--use-lit', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/stage1/bin/llvm-lit', b'--build-tool-options', b'"-k"', b'--cmake-define=TEST_SUITE_FORTRAN:STRING=ON', b'--cmake-define=CMAKE_Fortran_COMPILER=/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/stage1.install/bin/flang', b'--cppflags', b'-mcpu=neoverse-512tvb -msve-vector-bits=256 -mllvm -treat-scalable-fixed-error-as-warning=false -O3', b'--threads=32', b'--build-threads=32'], attempting to kill
...
-- Looking for __init_cpu_features - not found
-- Looking for __ARM_NEON
-- Looking for __ARM_NEON - found
-- No reference output found for test aarch64_neon_intrinsics
-- Found compiler-rt builtin library: libclang_rt.builtins.a
-- Performing Test COMPILER_HAS_MATRIX_FLAG
-- Performing Test COMPILER_HAS_MATRIX_FLAG - Success
-- Looking for mmap
-- Looking for mmap - found
-- Configuring done (34.7s)
command timed out: 1200 seconds without output running [b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/test/sandbox/bin/python', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/test/sandbox/bin/lnt', b'runtest', b'test-suite', b'--no-timestamp', b'--sandbox', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/test/sandbox', b'--test-suite', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/test/test-suite', b'--cc', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/stage1.install/bin/clang', b'--cxx', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/stage1.install/bin/clang++', b'--use-lit', b'/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/stage1/bin/llvm-lit', b'--build-tool-options', b'"-k"', b'--cmake-define=TEST_SUITE_FORTRAN:STRING=ON', b'--cmake-define=CMAKE_Fortran_COMPILER=/home/tcwg-buildbot/worker/clang-aarch64-sve-vls/stage1.install/bin/flang', b'--cppflags', b'-mcpu=neoverse-512tvb -msve-vector-bits=256 -mllvm -treat-scalable-fixed-error-as-warning=false -O3', b'--threads=32', b'--build-threads=32'], attempting to kill
process killed by signal 9
program finished with exit code -1
elapsedTime=1238.980044

```

</details>

https://github.com/llvm/llvm-project/pull/115581