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

[Pierre van Houtryve via llvm-commits]

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@@ -1512,6 +1512,24 @@ The AMDGPU backend supports the following calling conventions:
 
      =============================== ==========================================================
 
+AMDGPU MCExpr
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Pierre-vh wrote:

Did you try to render the docs to check the formatting?

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