[clang] [Bounds-Safety] Add sized_by, counted_by_or_null & sized_by_or_null (PR #93231)

[Dan Liew via cfe-commits]

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@@ -8641,22 +8641,33 @@ enum class CountedByInvalidPointeeTypeKind {
   VALID,
 };
 
-static bool CheckCountedByAttrOnField(
-    Sema &S, FieldDecl *FD, Expr *E,
-    llvm::SmallVectorImpl<TypeCoupledDeclRefInfo> &Decls) {
+static bool
+CheckCountedByAttrOnField(Sema &S, FieldDecl *FD, Expr *E,
+                          llvm::SmallVectorImpl<TypeCoupledDeclRefInfo> &Decls,
+                          bool CountInBytes, bool OrNull) {
   // Check the context the attribute is used in
 
+  unsigned Kind = CountInBytes;
+  if (OrNull)
+    Kind += 2;
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delcypher wrote:

Rather than magic constants it might be better to use an enum that you refer to here and in `DiagnosticSemaKinds.td` so that it's more readable.

https://github.com/llvm/llvm-project/pull/93231