[clang] Support MemProf on darwin (PR #69640)

[Teresa Johnson via cfe-commits]

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@@ -63,6 +57,23 @@ struct AP64 { // Allocator64 parameters. Deliberately using a short name.
 template <typename AddressSpaceView>
 using PrimaryAllocatorASVT = SizeClassAllocator64<AP64<AddressSpaceView>>;
 using PrimaryAllocator = PrimaryAllocatorASVT<LocalAddressSpaceView>;
+#endif
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teresajohnson wrote:

Combine these 2 lines into an "#else" ?

https://github.com/llvm/llvm-project/pull/69640