[llvm] [NVPTX] Improve device function byval parameter lowering (PR #129188)

[Alex MacLean via llvm-commits]

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@@ -2688,29 +2688,14 @@ def DeclareScalarRegInst :
             ".reg .b$size param$a;",
             [(DeclareScalarParam (i32 imm:$a), (i32 imm:$size), (i32 1))]>;
 
-class MoveParamInst<ValueType T, NVPTXRegClass regclass, string asmstr> :
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AlexMaclean wrote:

There are lots of other cases where we generate mov instructions but mov param is a special case where we move an address into a register. This code is dead and should be removed. 

https://github.com/llvm/llvm-project/pull/129188