[llvm] [Attributor] Do not optimize away externally_initialized loads. (PR #128170)

[Nikita Popov via llvm-commits]

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@@ -259,11 +259,16 @@ AA::getInitialValueForObj(Attributor &A, const AbstractAttribute &QueryingAA,
     if (!Initializer)
       return nullptr;
   } else {
-    if (!GV->hasLocalLinkage() &&
-        (GV->isInterposable() || !(GV->isConstant() && GV->hasInitializer())))
-      return nullptr;
-    if (!GV->hasInitializer())
-      return UndefValue::get(&Ty);
+    if (GV->hasLocalLinkage()) {
+      // Uninitialized global with local linkage.
+      if (!GV->hasInitializer())
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nikic wrote:

On a second look, we do have a verifier check here: https://github.com/llvm/llvm-project/blob/e6a0ee3d1d12c9c02c1a361109e282d18dd2430c/llvm/lib/IR/Verifier.cpp#L735-L736

So I believe you should just drop the !hasInitializer check here. (Or make it an assert.)

https://github.com/llvm/llvm-project/pull/128170