[llvm] [Attributor] Indicate optimistic fixed point if an instruction already has non-zero address space (PR #101589)

[Shilei Tian via llvm-commits]

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@@ -12491,6 +12491,9 @@ struct AAAddressSpaceImpl : public AAAddressSpace {
   void initialize(Attributor &A) override {
     assert(getAssociatedType()->isPtrOrPtrVectorTy() &&
            "Associated value is not a pointer");
+    auto *PtrTy = cast<PointerType>(getAssociatedType());
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shiltian wrote:

well, it is needed as `getAddressSpace` is a method of `PointerType` instead of `Type`.

https://github.com/llvm/llvm-project/pull/101589