1 files changed, 79 insertions, 0 deletions

diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
index 33b1d8ca4dfa..eba7267904fb 100644
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -2552,6 +2552,12 @@ bool Sema::CheckFunctionReturnType(QualType T, SourceLocation Loc) {
     return true;
   }
 
+  // __ptrauth is illegal on a function return type.
+  if (T.getPointerAuth()) {
+    Diag(Loc, diag::err_ptrauth_qualifier_invalid) << T << 0;
+    return true;
+  }
+
   if (T.hasNonTrivialToPrimitiveDestructCUnion() ||
       T.hasNonTrivialToPrimitiveCopyCUnion())
     checkNonTrivialCUnion(T, Loc, NTCUC_FunctionReturn,
@@ -2657,6 +2663,10 @@ QualType Sema::BuildFunctionType(QualType T,
     } else if (ParamType->isWebAssemblyTableType()) {
       Diag(Loc, diag::err_wasm_table_as_function_parameter);
       Invalid = true;
+    } else if (ParamType.getPointerAuth()) {
+      // __ptrauth is illegal on a function return type.
+      Diag(Loc, diag::err_ptrauth_qualifier_invalid) << T << 1;
+      Invalid = true;
     }
 
     // C++2a [dcl.fct]p4:
@@ -4974,6 +4984,11 @@ static TypeSourceInfo *GetFullTypeForDeclarator(TypeProcessingState &state,
         }
       }
 
+      // __ptrauth is illegal on a function return type.
+      if (T.getPointerAuth()) {
+        S.Diag(DeclType.Loc, diag::err_ptrauth_qualifier_invalid) << T << 0;
+      }
+
       if (LangOpts.OpenCL) {
         // OpenCL v2.0 s6.12.5 - A block cannot be the return value of a
         // function.
@@ -8333,6 +8348,65 @@ static void HandleNeonVectorTypeAttr(QualType &CurType, const ParsedAttr &Attr,
   CurType = S.Context.getVectorType(CurType, numElts, VecKind);
 }
 
+/// Handle the __ptrauth qualifier.
+static void HandlePtrAuthQualifier(ASTContext &Ctx, QualType &T,
+                                   const ParsedAttr &Attr, Sema &S) {
+
+  assert((Attr.getNumArgs() > 0 && Attr.getNumArgs() <= 3) &&
+         "__ptrauth qualifier takes between 1 and 3 arguments");
+  Expr *KeyArg = Attr.getArgAsExpr(0);
+  Expr *IsAddressDiscriminatedArg =
+      Attr.getNumArgs() >= 2 ? Attr.getArgAsExpr(1) : nullptr;
+  Expr *ExtraDiscriminatorArg =
+      Attr.getNumArgs() >= 3 ? Attr.getArgAsExpr(2) : nullptr;
+
+  unsigned Key;
+  if (S.checkConstantPointerAuthKey(KeyArg, Key)) {
+    Attr.setInvalid();
+    return;
+  }
+  assert(Key <= PointerAuthQualifier::MaxKey && "ptrauth key is out of range");
+
+  bool IsInvalid = false;
+  unsigned IsAddressDiscriminated, ExtraDiscriminator;
+  IsInvalid |= !S.checkPointerAuthDiscriminatorArg(IsAddressDiscriminatedArg,
+                                                   Sema::PADAK_AddrDiscPtrAuth,
+                                                   IsAddressDiscriminated);
+  IsInvalid |= !S.checkPointerAuthDiscriminatorArg(
+      ExtraDiscriminatorArg, Sema::PADAK_ExtraDiscPtrAuth, ExtraDiscriminator);
+
+  if (IsInvalid) {
+    Attr.setInvalid();
+    return;
+  }
+
+  if (!T->isSignableType() && !T->isDependentType()) {
+    S.Diag(Attr.getLoc(), diag::err_ptrauth_qualifier_nonpointer) << T;
+    Attr.setInvalid();
+    return;
+  }
+
+  if (T.getPointerAuth()) {
+    S.Diag(Attr.getLoc(), diag::err_ptrauth_qualifier_redundant)
+        << T << Attr.getAttrName()->getName();
+    Attr.setInvalid();
+    return;
+  }
+
+  if (!S.getLangOpts().PointerAuthIntrinsics) {
+    S.Diag(Attr.getLoc(), diag::err_ptrauth_disabled) << Attr.getRange();
+    Attr.setInvalid();
+    return;
+  }
+
+  assert((!IsAddressDiscriminatedArg || IsAddressDiscriminated <= 1) &&
+         "address discriminator arg should be either 0 or 1");
+  PointerAuthQualifier Qual = PointerAuthQualifier::Create(
+      Key, IsAddressDiscriminated, ExtraDiscriminator,
+      PointerAuthenticationMode::SignAndAuth, false, false);
+  T = S.Context.getPointerAuthType(T, Qual);
+}
+
 /// HandleArmSveVectorBitsTypeAttr - The "arm_sve_vector_bits" attribute is
 /// used to create fixed-length versions of sizeless SVE types defined by
 /// the ACLE, such as svint32_t and svbool_t.
@@ -8788,6 +8862,11 @@ static void processTypeAttrs(TypeProcessingState &state, QualType &type,
       HandleOpenCLAccessAttr(type, attr, state.getSema());
       attr.setUsedAsTypeAttr();
       break;
+    case ParsedAttr::AT_PointerAuth:
+      HandlePtrAuthQualifier(state.getSema().Context, type, attr,
+                             state.getSema());
+      attr.setUsedAsTypeAttr();
+      break;
     case ParsedAttr::AT_LifetimeBound:
       if (TAL == TAL_DeclChunk)
         HandleLifetimeBoundAttr(state, type, attr);