check that devices match in the command buffer emulation layer

[bashbaug]

Specifically, check for this error condition for clEnqueueCommandBufferKHR:

CL_INVALID_DEVICE if any element of queues does not have the same device as the command-queue set on command_buffer creation at the same list index.

This is important for multi-device contexts, especially heterogeneous multi-device contexts, where a command-queue may be created against the same context but be for a very different device.

[Copilot]

Pull request overview

Adds stricter validation in the command-buffer emulation layer to ensure that queues passed to clEnqueueCommandBufferKHR are associated with the same device as the queue used when the command buffer was created, improving correctness for multi-device (including heterogeneous) contexts.

Changes:

• Query the device associated with the command-buffer’s creation queue.
• For each enqueue-time queue, query its device and return CL_INVALID_DEVICE when it does not match the command-buffer device.

Suppressed comments (1)

layers/10_cmdbufemu/emulate.cpp:1537

• clGetCommandQueueInfo for queue_device ignores its return value. On failure, queue_device may remain null and the device-match check can incorrectly pass/fail. Handle the error and return it before comparing device IDs.

            cl_device_id queue_device = nullptr;
            g_pNextDispatch->clGetCommandQueueInfo(
                queues[q],
                CL_QUEUE_DEVICE,
                sizeof(queue_device),

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