sycl: support non-contiguous input in PAD op

[aicss-genai]

Overview

Authors

• @unrahul
• @ctao456
• @malsbat
• @YuningQiu
• @vvravi1
• @zhiqitao-intel

pad_f32 previously assumed contiguous source strides and reconstructed ne00/ne01/ne02 from ne - lp - rp. This broke when the source tensor had non-contiguous strides (common for views).

Pass s00..s03 (source strides in elements) through to the kernel and index with i03*s03 + i02*s02 + i01*s01 + i00*s00. Also switches the grid layout to sycl::range<3> order to match the rest of the backend.

Additional information

Part of work originally submitted as #22066 — splitting per reviewer request.

Requirements

• I have read and agree with the contributing guidelines
• AI usage disclosure: Yes. This work was partially produced with an agentic engineering approach: agents surface issues and explore experiments while engineers identify and reject candidates using domain knowledge. Human feedback involved.

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[arthw]

It's good job!

Thank you!

[malsbat]

Looks like CI failures are due to unreliable tests. I will do a merge from upstream to trigger a rebuild.

[ctao456]

Thank you @NeoZhangJianyu @CISC !

Could you help us with the merge process? CI tests may require rebuild still due to instability. Thanks.

[CISC]

Could you help us with the merge process? CI tests may require rebuild still due to instability. Thanks.

CI failures are unrelated, @arthw will merge when ready.

[arthw]

@ctao456
Yes, I will merge it if the rerun CI is stall fault.

Thank you!