[clang] [clang][CodeGen] Introduce class RawAddress and modify Address in preparation for adding information to it that is needed for pointer authentication (PR #67454)

[Florian Hahn via cfe-commits]

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@@ -15,35 +15,42 @@
 #define LLVM_CLANG_LIB_CODEGEN_ADDRESS_H
 
 #include "clang/AST/CharUnits.h"
+#include "clang/AST/Type.h"
 #include "llvm/ADT/PointerIntPair.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/Support/MathExtras.h"
 
 namespace clang {
 namespace CodeGen {
 
+class Address;
+class CGBuilderTy;
+class CodeGenFunction;
+class CodeGenModule;
+
 // Indicates whether a pointer is known not to be null.
 enum KnownNonNull_t { NotKnownNonNull, KnownNonNull };
 
-/// An aligned address.
-class Address {
+class RawAddress {
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fhahn wrote:

Would be good to have a brief comment here documenting `RawAddress`

https://github.com/llvm/llvm-project/pull/67454