Fix oob in test_conformance/Test_vStoreHalf

[pursuezhao]

Out-of-bound access happens when off is not less than lim.

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[pursuezhao]

hi there, could anyone help to review this change?

[bashbaug]

Hi, can you please check that you (or your company) has signed the Contributor License Agreement (see https://github.com/KhronosGroup/OpenCL-CTS/pull/1434#issuecomment-1151767261)? We won't be able to merge this change otherwise. Thanks!

[pursuezhao]

Hi, can you please check that you (or your company) has signed the Contributor License Agreement (see #1434 (comment))? We won't be able to merge this change otherwise. Thanks!

hi, thanks for your kindly reminding, I have signed the license agreement.

[pursuezhao]

Hi, can you please check that you (or your company) has signed the Contributor License Agreement (see #1434 (comment))? We won't be able to merge this change otherwise. Thanks!

hi, could you help to have a review on this change?

[EwanC]

I tried this git branch locally, but none of these new conditions checking for oob were hit when run against our implementation.

Would you be able to elaborate on what the values of off and lim are which these if statements catch? From a skim of the code lim seems derived from BUFFER_SIZE which is constant, but off can be influenced by the thread count. I tried running the test with 1, 3, 8, & 24 threads but couldn't see the oob.