Why is depth/stencil buffer loaded/stored twice in xcode gpu capture?

I used xcode gpu capture to profile render pipeline's bandwidth of my game.Then i found depth buffer and stencil buffer use the same buffer whitch it's format is Depth32Float_Stencil8.

But why in a single pass of pipeline, this buffer was loaded twice, and the Load Attachment Size of Encoder Statistics was double.

Is there any bug with xcode gpu capture?Or the pass really loaded the buffer twice times?

Why is depth/stencil buffer loaded/stored twice in xcode gpu capture?
 
 
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