[SYCL] Remove diagnostics emission from Integration header functional…

…ity (intel#2474)

Using Clang's Visitor classes to walk the template type parameter - KernelName
to emit the following diagnostics:

- Kernel name is invalid. Unscoped enum requires fixed underlying type - enum
   in template params
- Kernel needs to have a globally-visible name
- Kernel name is missing

[SYCL] Fix OpenCL version check when verifying SPIR-V online compilat…

…ion support (intel#2445)

Enumerate through historic OpenCL versions, like in the plugin.

[SYCL]: basic support of contexts with multiple devices in Level-Zero (…

…intel#2440)

Signed-off-by: Sergey V Maslov <[email protected]>

[SYCL][L0]: Check Queue refcnt prior to using members in event wait/r…

…elease (intel#2471)

- If the Queue was cleared of L0 data structures ie Refcnt == 0
  then all L0 data structures in the pi_queue can no longer be used.
- Prevent EventWait and EventRelease from using invalid data structures
  if the Queue has already been cleared.

Signed-off-by: Spruit, Neil R <[email protected]>

[SYCL] Refactor -fsycl-esimd and -fsycl-int-header options (intel#2466)

-fsycl-int-header option initialization code moved closer to code
section processing other SYCL options.

-fsycl-esimd enables optimizations in SYCL mode, which is not necessary
after intel@5976ff0

[SYCL][FPGA] Align clang with new spec of accessor_property_list (int…

…el#2447)

Signed-off-by: Mikhail Lychkov <[email protected]>

2020-09 release

[SYCL][Doc] Move USM extension doc to Khronos (intel#2457)

Signed-off-by: James Brodman <[email protected]>

[SYCL] Diagnose attempt to pass pointer to VLA as kernel arg (intel#2441

)

VLA as well as pointers to VLA require additional AST transformation to make
emission of corresponding type in LLVM IR possible. Without this transformation
Codegen just crashes.
Implementing this transformation is not reasonable whereas SYCL standard
doesn't allow VLA in device code, so emit an error in case if pointer to
VLA is passed as kernel argument.

[SYCL][Spec] Make accessor_properties a ONEAPI extension and add the …

…buffer_location extension (intel#2439)

* Made accessor_properties a ONEAPI extension.

* Added buffer_location, an INTEL extension that builds on accessor_properties