[llvm] [NVPTX] add an optional early copy of byval arguments (PR #113384)

[Akshay Deodhar via llvm-commits]

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@@ -612,29 +638,8 @@ void NVPTXLowerArgs::handleByValParam(const NVPTXTargetMachine &TM,
 
     // Do not replace Arg in the cast to param space
     CastToParam->setOperand(0, Arg);
-  } else {
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akshayrdeodhar wrote:

to clarify: any readonly byvals which were not formerly lowered to allocas will get lowered to allocas, but SROA will convert loads from the allocas to loads from the byval pointer?

https://github.com/llvm/llvm-project/pull/113384