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

[via llvm-commits]

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@@ -5301,6 +5319,23 @@ TEST_F(OpenMPIRBuilderTest, TargetRegionDevice) {
       Constant::getNullValue(PointerType::get(Ctx, 0)),
       Constant::getNullValue(PointerType::get(Ctx, 0))};
 
+  auto SimpleArgAccessorCB = [&](llvm::Argument &Arg, llvm::Value *Input,
+                                 IRBuilderBase &Builder) {
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agozillon wrote:

Yeah it's not a big deal, just makes diff'ng things easier, and means there's less chance of breakage in the future if we stay consistent.

Sounds good, thank you for your input, and thank you as well @TIFitis 

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