[clang] [HIP][NFC] Refactor managed var codegen (PR #85976)

[Yaxun Liu via cfe-commits]

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@@ -1160,9 +1152,8 @@ void CGNVCUDARuntime::createOffloadingEntries() {
 
 // Returns module constructor to be added.
 llvm::Function *CGNVCUDARuntime::finalizeModule() {
+  transformManagedVars();
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yxsamliu wrote:

we did the equivalent transformation previously during registration of managed var by calling replaceManagedVar directly, so it is actually NFC. We have lit test https://github.com/llvm/llvm-project/blob/main/clang/test/CodeGenCUDA/managed-var.cu that covers transformation in both device and host code.

We also have execution tests in hip-tests https://github.com/llvm/llvm-project/blob/main/clang/test/CodeGenCUDA/managed-var.cu


https://github.com/llvm/llvm-project/pull/85976