texture gather() problem in Simulator

Any reason to expect a texture gather on a 2D single channel ushort texture in a fragment shader to not work in Simulator Version 11.5 (921.9.1) on
MacBook Pro (Retina, 15-inch, Mid 2015) with AMD Radeon R9 M370X 2 GB ? (It's returning 0x1B for all four values)

When target is Apple TV 4K device, it works as fine.
There is no reason this shouldn't work on the simulator.

Please file a bug report via Feedback Assistant.  If you're able to provide an Xcode project or even the Metal shader you're seeing this problem with, that would be helpful.  Also if you repost the Feedback Assistant number here, we can route the information directly to the engineers who work on Metal in the simulator
Bug report is FB7799650.
Also, discovered issue only occurs on discrete GPU, works as expected on integrated graphics.
Thank bswift. Sent the request with your project to our AMD driver engineers to take a look.
texture gather() problem in Simulator
 
 
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