[llvm] [OpenMP][OpenMPIRBuilder][NFC] Move copyInput to a passed in lambda function (PR #68124)

[Akash Banerjee via llvm-commits]

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@@ -2166,6 +2166,9 @@ class OpenMPIRBuilder {
   using TargetBodyGenCallbackTy = function_ref<InsertPointTy(
       InsertPointTy AllocaIP, InsertPointTy CodeGenIP)>;
 
+  using TargetGenArgAccessorsCallbackTy = function_ref<Value *(
+      Argument &Arg, Value *Input, IRBuilderBase &Builder)>;
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TIFitis wrote:

I don't think passing around the builder is the coorect approach to solve this.

We should be passing and returning the inserpoints instead. We should pass the AllocaIP and CodeGenIP to the Callback, and the CB should return the new position of the IP.

If new allocas are not needed the we can perhaps ignore the AllocaIP.

https://github.com/llvm/llvm-project/pull/68124