[llvm] [AMDGPU][MC] Disassembler warning for v_cmpx instructions (PR #127925)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,407 @@
+# RUN: llvm-mc -triple=amdgcn -mcpu=gfx1010 -disassemble -show-encoding < %s 2>&1 | FileCheck -check-prefixes=GFX10 %s
+
+### class
+# GFX10: [[@LINE+2]]:1: warning: potentially undefined instruction encoding
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arsenm wrote:

It would be nice if the instruction was more specific 

https://github.com/llvm/llvm-project/pull/127925