[llvm] [AMDGPU][MC] Disable sendmsg SYSMSG_OP_HOST_TRAP_ACK on gfx9+ (PR #90203)

[Matt Arsenault via llvm-commits]

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@@ -41,3 +41,6 @@ global_load_dword v[2:3], off
 
 scratch_load_dword v2, off, offset:256
 // GFX9ERR: :[[@LINE-1]]:{{[0-9]+}}: error: too few operands for instruction
+
+s_sendmsg sendmsg(MSG_SYSMSG, SYSMSG_OP_HOST_TRAP_ACK)
+// GFX9ERR: :[[@LINE-1]]:{{[0-9]+}}: error: invalid operation id
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arsenm wrote:

Error message leaves something to be desired. Can it mention the lack of support on the target, that shows it is recognized? 

https://github.com/llvm/llvm-project/pull/90203