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[CODEOWNERS] Add Soumi to help with FE reviews (intel#4714)

[sycl-post-link] Several fixes for 'default' spec constants (intel#4649)

Fixed collection of default values of `half` scalar spec constants in
`SpecConstantsPass` as well as handling of vectors and arrays there.

[SYCL] Align device::create_sub_devices exceptions with SYCL 2020 (in…

…tel#4670)

According to the SYCL 2020 spec device::create_sub_devices
should throw an exception with either
errc::feature_not_supported or errc::invalid error codes. The
feature_not_supported side is working fine. But for invalid
values, we presently just lean on the default exception thrown
by plugin::call() which is always a runtime_error exception
subclass. Here we are adding new specializations for
plugin::call() and plugin::checkPiResult that accept sycl::errc
values and use those specializations from
device::create_sub_devices() to ensure that errc::invalid is the
error code in the exception (instead of errc::runtime)

This bug is presently tripping the SYCL-CTS tests, thus the need to fix it.

Signed-off-by: Chris Perkins <chris.perkins@intel.com>

[SYCL] Fix backwards compatibility for libraries in archive format (i…

…ntel#4685)

With `-sycldevice` triple environment removal (as performed in
intel#3929), backwards compatibility has been enforced for SYCL
objects/object-format libraries only. To ensure that `.a` libraries
(archives) built by older compiler versions are usable with newer
compiler version, adjust `clang-offload-deps` to consider
`-sycldevice`-marked symbols when encountering a SYCL target.

Signed-off-by: Artem Gindinson <artem.gindinson@intel.com>

[SYCL][XPTI] Revisit resource management strategy (intel#4494)

Global objects are typically destroyed on process tear down, but the order of the destructor calls is undefined. Since SYCL applications can potentially call SYCL APIs from global context, XPTI and all of its resources have to outlive user application. This patch refactors XPTI proxy library and framework to allocate global objects on heap and manages their lifetime based on communications from traced application.

Each user of XPTI (e.g. SYCL runtime) has to call xptiFrameworkInitialize() once prior to any other XPTI API. When application is done collecting trace information, it must close streams and then call xptiFrameworkFinalize().

The XPTI framework will maintain a reference counter, and will only free resources and unload libraries, when the counter hits 0. This will allow the subscribers to survive past DllMain call or global shared library destructor.

[SYCL] Make kernel_bundle interop more conformant (intel#4672)

Mark kernel bundle's get_native as const to fix sycl::get_native compilation issues, fix incorrect kernel bundle trait.
Tests: intel/llvm-test-suite#489

[SYCL][HIP] Fix MemBufferFill for nvidia platform (intel#4629)

[SYCL] Exclude exported symbols from kernel bundles (intel#4660)

Because exported device functions are interspersed with kernels in the offload entries they are thought to be kernels in device images. These changes use the list of exported symbols generated by sycl-post-link to filter out the exported device functions when creating device images.

[SYCL] Fix overwriting insert to sub_group_mask (intel#4656)

Make sure that old value is cleared when inserted bits ovewrite whole
mask.