[llvm] [AMDGPU] Add AMDGPU specific variadic operation MCExprs (PR #82022)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,29 @@
+// RUN: not llvm-mc -triple amdgcn-amd-amdhsa %s 2>&1 | FileCheck --check-prefix=ASM %s
+
+// ASM: 20:22: error: empty max expression
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arsenm wrote:

can you move the checks so each one is next to the relevant code? Also should use [[@LINE+1]] instead of hardcoded line numbers 

https://github.com/llvm/llvm-project/pull/82022