Apparently missing test with push constants with statically unused push constants in pipeline

[Themaister]

We ran into a case on Mali where:

• A pipeline layout declared a push constant range.
• The pipeline using said layout statically does not access push constants.
• vkCmdPushConstant is not called.
• On vkCmdDraw* the driver crashes on CPU.

Just pushing something worked around the crash.

The wording from spec:

For each push constant that is statically used by the VkPipeline bound to the pipeline bind
point used by this command, a push constant value must have been set for the same
pipeline bind point, with a VkPipelineLayout that is compatible for push constants, with
the VkPipelineLayout used to create the current VkPipeline, as described in Pipeline Layout
Compatibility

Statically used is key here. I suspect there is no CTS test to cover this particular edge case.

[flyinghead]

Here is the code I'm running and the fix I made to overcome the issue: flyinghead/flycast@c683e0d

I use a single pipeline layout that has a 20-byte push constant range. With Mali G51 with driver r18, I get a crah if push constants are not pushed, even though they are not used by the current pipeline.

[alegal-arm]

@Themaister our driver team was not to reproduce this based on the description given. We might be missing something. Would it be possible to share a reproducing apk?

[flyinghead]

Here is an apk of the app having the issue: http://flycast-builds.s3.amazonaws.com/android/heads/fh/vulkan-7898707/flycast-debug-7898707.apk
You can use the following content with the app: https://sourceforge.net/projects/testsuite240p/files/Dreamcast/240p-DC-PVR-1.25.zip/download

Set the renderer to Vulkan in Settings > Video.

[JoergArm]

Hello!
We have tried the provided apk on an S10e running r19, a P30 running r18, and a stock S10 running r16 - without being able to observe the reported crash (the apk crashes before even creating a Vulkan device on drivers which only support Vulkan 1.0). As we still have no luck with the internal reproducer either some more questions follow which could help us identifying the issue:
@flyinghead - Please could you tell us on which G51 device you observed the problem?
@Themaister - Please could you describe the environment you hit this issue on?

Many thanks,
Jörg

[flyinghead]

The phone I'm testing with is a Huawei P smart 2019, running the latest Android 10 from Huawei.

[Themaister]

@JoergArm I haven't hit this issue first hand, this report is based on a debugging session we had back when this issue was reported. My S9 has not received any OTA beyond r16 fwiw.

[JoergArm]

We have been unable to confirm the issue on the Huawei P smart 2019 device (there are application crashes before a Vulkan device is created which we consider not related).
So, unfortunately, for the time being we cannot not give advice on which tests should be added to the CTS.