Giovanni Mascellani (@giomasce) commented about tests/hlsl/entry-point-semantics.shader_test:
[test] draw quad -todo(sm>=6) probe (0, 0) rgba (10.0, 11.0, 30.0, 31.0) +probe (0, 0) rgba (10.0, 11.0, 30.0, 31.0)
+% dxcompiler emits correct array addressing. +[require] +shader model < 6.0
It might make sense to add the corresponding test for SM6, though.