[clang] [Clang][CodeGen] Start migrating away from assuming the Default AS is 0 (PR #88182)

[Alex Voicu via cfe-commits]

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@@ -3581,8 +3582,10 @@ ConstantAddress CodeGenModule::GetAddrOfTemplateParamObject(
       isExternallyVisible(TPO->getLinkageAndVisibility().getLinkage())
           ? llvm::GlobalValue::LinkOnceODRLinkage
           : llvm::GlobalValue::InternalLinkage;
-  auto *GV = new llvm::GlobalVariable(getModule(), Init->getType(),
-                                      /*isConstant=*/true, Linkage, Init, Name);
+  auto *GV = new llvm::GlobalVariable(
+      getModule(), Init->getType(),
+      /*isConstant=*/true, Linkage, Init, Name, nullptr,
+      llvm::GlobalValue::NotThreadLocal, GlobalsInt8PtrTy->getAddressSpace());
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AlexVlx wrote:

At the same time, it's not terribly costly (except for lines of code), and, unfortunately, there might be quite a few "broken" datalayouts (NVPTX is in the same boat, as is DirectX). I'm not entirely convinced the breakage is not an intentional design choice for pseudo/meta/abstract targets (abusing nomenclature, apologies). I'd submit that this (the changes/CodeGen) is still in Clang, which would still fall under the "the FE/language has to deal with ASes having special properties, LLVM shouldn't care", and it is an artifact of composing AS aware languages (OCL/CUDA/HIP etc.) with said abstract targets.

https://github.com/llvm/llvm-project/pull/88182