[llvm] [AMDGPU] Add test for v_fmamk_f16/v_fmaak_f16 in real-true16. NFC (PR #173307)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,31 @@
+# RUN: not llc -mtriple=amdgcn -mcpu=gfx1100 -mattr=+real-true16 -run-pass=machineverifier -filetype=null %s 2>&1 | FileCheck %s -check-prefix=GFX11
+# RUN: not llc -mtriple=amdgcn -mcpu=gfx1100 -mattr=+real-true16 -start-before=greedy,0 -stop-after=virtregrewriter,2 -o - %s 2>&1 | FileCheck %s -check-prefix=GFX11
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arsenm wrote:

I'm not sure what the point of the second run line is, the error seems to come from the MIR parser (instead of the machine verifier, for some reason)? 

Test also belongs in test/MachineVerifier or CodeGen/MIR

https://github.com/llvm/llvm-project/pull/173307