[llvm] [NVPTX] support immediate values in st.param instructions (PR #91523)

[Alex MacLean via llvm-commits]

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@@ -2637,25 +2637,49 @@ class LoadParamRegInst<NVPTXRegClass regclass, string opstr> :
                 [(set regclass:$dst, (LoadParam (i32 0), (i32 imm:$b)))]>;
 
 let mayStore = true in {
-  class StoreParamInst<NVPTXRegClass regclass, string opstr> :
+  class StoreParamInstReg<NVPTXRegClass regclass, string opstr> :
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AlexMaclean wrote:

If I were to do this how would I define the `StoreParamI8TruncI32` and `StoreParamI8TruncI64` instructions for which I do not want a `_i` variant? 

https://github.com/llvm/llvm-project/pull/91523