[llvm] [mlir] [llvm][mlir][OMPIRBuilder] Translate omp.single's copyprivate (PR #80488)

[Kareem Ergawy via llvm-commits]

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@@ -656,8 +656,26 @@ convertOmpSingle(omp::SingleOp &singleOp, llvm::IRBuilderBase &builder,
                         moduleTranslation, bodyGenStatus);
   };
   auto finiCB = [&](InsertPointTy codeGenIP) {};
+
+  // Handle copyprivate
+  Operation::operand_range cpVars = singleOp.getCopyprivateVars();
+  std::optional<ArrayAttr> cpFuncs = singleOp.getCopyprivateFuncs();
+  llvm::SmallVector<llvm::Value *> llvmCPVars;
+  llvm::SmallVector<llvm::Function *> llvmCPFuncs;
+  for (size_t i = 0, e = cpVars.size(); i < e; ++i) {
+    llvmCPVars.push_back(moduleTranslation.lookupValue(cpVars[i]));
+    auto llvmFuncOp = SymbolTable::lookupNearestSymbolFrom<LLVM::LLVMFuncOp>(
+        singleOp, cast<SymbolRefAttr>((*cpFuncs)[i]));
+    llvmCPFuncs.push_back(
+        moduleTranslation.lookupFunction(llvmFuncOp.getName()));
+  }
+  llvm::Value *didIt = nullptr;
+  if (!llvmCPVars.empty())
+    didIt = builder.CreateAlloca(llvm::Type::getInt32Ty(builder.getContext()));
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ergawy wrote:

If the creation of `didIt` is tied to the presence or absence of `copyprivate` variables, I think we can move this `if` condition to the `createSingle` instead and make its responsibility to manage `didIt` altogether.

https://github.com/llvm/llvm-project/pull/80488