[clang] [PAC] Add support for __ptrauth type qualifier (PR #100830)

[Aaron Ballman via cfe-commits]

================
@@ -19370,9 +19376,14 @@ void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
             RecordArgPassingKind::CanNeverPassInRegs)
           Record->setArgPassingRestrictions(
               RecordArgPassingKind::CanNeverPassInRegs);
-      } else if (FT.getQualifiers().getObjCLifetime() == Qualifiers::OCL_Weak)
+      } else if (FT.getQualifiers().getObjCLifetime() == Qualifiers::OCL_Weak) {
         Record->setArgPassingRestrictions(
             RecordArgPassingKind::CanNeverPassInRegs);
+      } else if (PointerAuthQualifier Q = FT.getPointerAuth()) {
+        if (Q.isAddressDiscriminated())
+          Record->setArgPassingRestrictions(
+              RecordArgPassingKind::CanNeverPassInRegs);
----------------
AaronBallman wrote:

```suggestion
      } else if (PointerAuthQualifier Q = FT.getPointerAuth();
                 Q && Q.isAddressDiscriminated()) {
          Record->setArgPassingRestrictions(
              RecordArgPassingKind::CanNeverPassInRegs);
```

https://github.com/llvm/llvm-project/pull/100830