[llvm] [AMDGPU] Fix undivergent parameter pass using vgpr (PR #178198)

[Matt Arsenault via llvm-commits]

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@@ -30,6 +30,7 @@ namespace ISD {
     unsigned IsSExt : 1;     ///< Sign extended
     unsigned IsNoExt : 1;    ///< No extension
     unsigned IsInReg : 1;    ///< Passed in register
+    unsigned IsArgInReg : 1; ///< Is caller function's 'inreg' argument
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arsenm wrote:

This should not be necessary 

https://github.com/llvm/llvm-project/pull/178198