[SYCL][L0 v2] Fix bindless array image subregion copies

[mateuszpn]

Fix bindless array image subregion copies on Level Zero v2 (SYCL validation + UR region mapping)
Enable tests (previously failing and disabled with no tracking):
bindless_images/array/read_write_1d_subregion.cpp
bindless_images/array/read_write_2d_subregion.cpp

[pbalcer]

I have to admit, I'm not super well versed in image support in L0. Can you describe what the change is, and why it fixes the problem?

[mateuszpn]

The code is simplified now. Still, basically the change in level_zero adapter code fixes mapping of image region dimensions which is different in UR and L0 for 1DARRAY images. In particular, numbers of layers to copy in UR: Region-depth, L0: Height. Starting index UR: Origin->z, L0: OriginY

[mateuszpn]

Also 1D images need adjusting - UR allows Height and Depth to be 0 (only Width set to image size), while L0 needs them to be 1.

[AlexeySachkov]

Thank you for fixing this!

Conceptually this looks good to me (although I'm not a code owner anymore), but I do have a few notes/questions

[AlexeySachkov]

I see that L0 does not support arrays of 3d images, but briefly looking at the extension specification I couldn't find any restriction about that on the SYCL level.

Did I just missed it, or is it indeed missing from the spec?

If it is missing, I'm not asking to add it in this PR, but creating an issue to remind us about this would be helpful

[mateuszpn]

SYCL also does not support arrays of 3D images. The specification is not written clearly, but sentences like "... the 3rd dimension of the ranges represent the arrays' layer(s) being copied, regardless of whether the copy is performed on a 1D or 2D image array." indicate this. You can also see it in the code:

llvm/sycl/include/sycl/ext/oneapi/bindless_images_descriptor.hpp

Line 157 in 92aea26

// Image arrays must only be 1D or 2D.

[AlexeySachkov]

Do we also need to assert y == 0 for 1D array and z == 0 for 2D array?

[mateuszpn]

I believe the current code is correct as-is. The assertions properly validate that:

• Unused dimensions are zero (y and z for 1D, z for 2D)
• Array layer dimensions (z for both 1D and 2D arrays) are allowed to be non-zero