[Sema] Fix Modified Type in address_space AttributedType

This is a fix for https://reviews.llvm.org/D51229 where we pass the
address_space qualified type as the modified type of an AttributedType. This
change now instead wraps the AttributedType with either the address_space
qualifier or a DependentAddressSpaceType.

Differential Revision: https://reviews.llvm.org/D55447

llvm-svn: 351997

clang/docs/ReleaseNotes.rst

@@ -162,7 +162,11 @@ clang-format
 libclang
 --------
 
-...
+- When `CINDEXTEST_INCLUDE_ATTRIBUTED_TYPES` is not provided when making a
+  CXType, the equivalent type of the AttributedType is returned instead of the
+  modified type if the user does not want attribute sugar. The equivalent type
+  represents the minimally-desugared type which the AttributedType is
+  canonically equivalent to.
 
 
 Static Analyzer

clang/include/clang/Sema/Sema.h

@@ -1411,6 +1411,10 @@ public:
   QualType BuildVectorType(QualType T, Expr *VecSize, SourceLocation AttrLoc);
   QualType BuildExtVectorType(QualType T, Expr *ArraySize,
                               SourceLocation AttrLoc);
+  QualType BuildAddressSpaceAttr(QualType &T, LangAS ASIdx, Expr *AddrSpace,
+                                 SourceLocation AttrLoc);
+
+  /// Same as above, but constructs the AddressSpace index if not provided.
   QualType BuildAddressSpaceAttr(QualType &T, Expr *AddrSpace,
                                  SourceLocation AttrLoc);
 

clang/lib/AST/Type.cpp

@@ -3205,6 +3205,7 @@ bool AttributedType::isQualifier() const {
   case attr::TypeNullable:
   case attr::TypeNullUnspecified:
   case attr::LifetimeBound:
+  case attr::AddressSpace:
     return true;
 
   // All other type attributes aren't qualifiers; they rewrite the modified

clang/lib/AST/TypePrinter.cpp

@@ -257,11 +257,17 @@ bool TypePrinter::canPrefixQualifiers(const Type *T,
     case Type::FunctionProto:
     case Type::FunctionNoProto:
     case Type::Paren:
-    case Type::Attributed:
     case Type::PackExpansion:
     case Type::SubstTemplateTypeParm:
       CanPrefixQualifiers = false;
       break;
+
+    case Type::Attributed: {
+      // We still want to print the address_space before the type if it is an
+      // address_space attribute.
+      const auto *AttrTy = cast<AttributedType>(T);
+      CanPrefixQualifiers = AttrTy->getAttrKind() == attr::AddressSpace;
+    }
   }
 
   return CanPrefixQualifiers;
@@ -1377,7 +1383,10 @@ void TypePrinter::printAttributedBefore(const AttributedType *T,
   if (T->getAttrKind() == attr::ObjCKindOf)
     OS << "__kindof ";
 
-  printBefore(T->getModifiedType(), OS);
+  if (T->getAttrKind() == attr::AddressSpace)
+    printBefore(T->getEquivalentType(), OS);
+  else
+    printBefore(T->getModifiedType(), OS);
 
   if (T->isMSTypeSpec()) {
     switch (T->getAttrKind()) {

clang/lib/Sema/SemaType.cpp

@@ -5787,28 +5787,27 @@ ParsedType Sema::ActOnObjCInstanceType(SourceLocation Loc) {
 // Type Attribute Processing
 //===----------------------------------------------------------------------===//
 
-/// BuildAddressSpaceAttr - Builds a DependentAddressSpaceType if an expression
-/// is uninstantiated. If instantiated it will apply the appropriate address space
-/// to the type. This function allows dependent template variables to be used in
-/// conjunction with the address_space attribute
-QualType Sema::BuildAddressSpaceAttr(QualType &T, Expr *AddrSpace,
-                                     SourceLocation AttrLoc) {
+/// Build an AddressSpace index from a constant expression and diagnose any
+/// errors related to invalid address_spaces. Returns true on successfully
+/// building an AddressSpace index.
+static bool BuildAddressSpaceIndex(Sema &S, LangAS &ASIdx,
+                                   const Expr *AddrSpace,
+                                   SourceLocation AttrLoc) {
   if (!AddrSpace->isValueDependent()) {
-
     llvm::APSInt addrSpace(32);
-    if (!AddrSpace->isIntegerConstantExpr(addrSpace, Context)) {
-      Diag(AttrLoc, diag::err_attribute_argument_type)
+    if (!AddrSpace->isIntegerConstantExpr(addrSpace, S.Context)) {
+      S.Diag(AttrLoc, diag::err_attribute_argument_type)
           << "'address_space'" << AANT_ArgumentIntegerConstant
           << AddrSpace->getSourceRange();
-      return QualType();
+      return false;
     }
 
     // Bounds checking.
     if (addrSpace.isSigned()) {
       if (addrSpace.isNegative()) {
-        Diag(AttrLoc, diag::err_attribute_address_space_negative)
+        S.Diag(AttrLoc, diag::err_attribute_address_space_negative)
             << AddrSpace->getSourceRange();
-        return QualType();
+        return false;
       }
       addrSpace.setIsSigned(false);
     }
@@ -5817,14 +5816,28 @@ QualType Sema::BuildAddressSpaceAttr(QualType &T, Expr *AddrSpace,
     max =
         Qualifiers::MaxAddressSpace - (unsigned)LangAS::FirstTargetAddressSpace;
     if (addrSpace > max) {
-      Diag(AttrLoc, diag::err_attribute_address_space_too_high)
+      S.Diag(AttrLoc, diag::err_attribute_address_space_too_high)
           << (unsigned)max.getZExtValue() << AddrSpace->getSourceRange();
-      return QualType();
+      return false;
     }
 
-    LangAS ASIdx =
+    ASIdx =
         getLangASFromTargetAS(static_cast<unsigned>(addrSpace.getZExtValue()));
+    return true;
+  }
 
+  // Default value for DependentAddressSpaceTypes
+  ASIdx = LangAS::Default;
+  return true;
+}
+
+/// BuildAddressSpaceAttr - Builds a DependentAddressSpaceType if an expression
+/// is uninstantiated. If instantiated it will apply the appropriate address
+/// space to the type. This function allows dependent template variables to be
+/// used in conjunction with the address_space attribute
+QualType Sema::BuildAddressSpaceAttr(QualType &T, LangAS ASIdx, Expr *AddrSpace,
+                                     SourceLocation AttrLoc) {
+  if (!AddrSpace->isValueDependent()) {
     if (DiagnoseMultipleAddrSpaceAttributes(*this, T.getAddressSpace(), ASIdx,
                                             AttrLoc))
       return QualType();
@@ -5845,6 +5858,14 @@ QualType Sema::BuildAddressSpaceAttr(QualType &T, Expr *AddrSpace,
   return Context.getDependentAddressSpaceType(T, AddrSpace, AttrLoc);
 }
 
+QualType Sema::BuildAddressSpaceAttr(QualType &T, Expr *AddrSpace,
+                                     SourceLocation AttrLoc) {
+  LangAS ASIdx;
+  if (!BuildAddressSpaceIndex(*this, ASIdx, AddrSpace, AttrLoc))
+    return QualType();
+  return BuildAddressSpaceAttr(T, ASIdx, AddrSpace, AttrLoc);
+}
+
 /// HandleAddressSpaceTypeAttribute - Process an address_space attribute on the
 /// specified type.  The attribute contains 1 argument, the id of the address
 /// space for the type.
@@ -5890,19 +5911,41 @@ static void HandleAddressSpaceTypeAttribute(QualType &Type,
       ASArgExpr = static_cast<Expr *>(Attr.getArgAsExpr(0));
     }
 
-    // Create the DependentAddressSpaceType or append an address space onto
-    // the type.
-    QualType T = S.BuildAddressSpaceAttr(Type, ASArgExpr, Attr.getLoc());
-
-    if (!T.isNull()) {
-      ASTContext &Ctx = S.Context;
-      auto *ASAttr = ::new (Ctx) AddressSpaceAttr(
-          Attr.getRange(), Ctx, Attr.getAttributeSpellingListIndex(),
-          static_cast<unsigned>(T.getQualifiers().getAddressSpace()));
-      Type = State.getAttributedType(ASAttr, T, T);
-    } else {
+    LangAS ASIdx;
+    if (!BuildAddressSpaceIndex(S, ASIdx, ASArgExpr, Attr.getLoc())) {
       Attr.setInvalid();
+      return;
     }
+
+    ASTContext &Ctx = S.Context;
+    auto *ASAttr = ::new (Ctx) AddressSpaceAttr(
+        Attr.getRange(), Ctx, Attr.getAttributeSpellingListIndex(),
+        static_cast<unsigned>(ASIdx));
+
+    // If the expression is not value dependent (not templated), then we can
+    // apply the address space qualifiers just to the equivalent type.
+    // Otherwise, we make an AttributedType with the modified and equivalent
+    // type the same, and wrap it in a DependentAddressSpaceType. When this
+    // dependent type is resolved, the qualifier is added to the equivalent type
+    // later.
+    QualType T;
+    if (!ASArgExpr->isValueDependent()) {
+      QualType EquivType =
+          S.BuildAddressSpaceAttr(Type, ASIdx, ASArgExpr, Attr.getLoc());
+      if (EquivType.isNull()) {
+        Attr.setInvalid();
+        return;
+      }
+      T = State.getAttributedType(ASAttr, Type, EquivType);
+    } else {
+      T = State.getAttributedType(ASAttr, Type, Type);
+      T = S.BuildAddressSpaceAttr(T, ASIdx, ASArgExpr, Attr.getLoc());
+    }
+
+    if (!T.isNull())
+      Type = T;
+    else
+      Attr.setInvalid();
   } else {
     // The keyword-based type attributes imply which address space to use.
     ASIdx = Attr.asOpenCLLangAS();
@@ -7346,9 +7389,11 @@ static void processTypeAttrs(TypeProcessingState &state, QualType &type,
           if (!IsTypeAttr)
             continue;
         }
-      } else if (TAL != TAL_DeclChunk) {
+      } else if (TAL != TAL_DeclChunk &&
+                 attr.getKind() != ParsedAttr::AT_AddressSpace) {
         // Otherwise, only consider type processing for a C++11 attribute if
         // it's actually been applied to a type.
+        // We also allow C++11 address_space attributes to pass through.
         continue;
       }
     }

clang/test/AST/address_space_attribute.cpp

@@ -0,0 +1,23 @@
+// RUN: %clang_cc1 %s -ast-dump | FileCheck %s
+
+// Veryify the ordering of the address_space attribute still comes before the
+// type whereas other attributes are still printed after.
+
+template <int I>
+void func() {
+  // CHECK: VarDecl {{.*}} x '__attribute__((address_space(1))) int *'
+  __attribute__((address_space(1))) int *x;
+
+  // CHECK: VarDecl {{.*}} a 'int * __attribute__((noderef))'
+  int __attribute__((noderef)) * a;
+
+  // CHECK: VarDecl {{.*}} y '__attribute__((address_space(2))) int *'
+  __attribute__((address_space(I))) int *y;
+
+  // CHECK: VarDecl {{.*}} z '__attribute__((address_space(3))) int *'
+  [[clang::address_space(3)]] int *z;
+}
+
+void func2() {
+  func<2>();
+}

clang/test/Index/print-type.m

@@ -19,6 +19,6 @@
 // CHECK: ObjCInstanceMethodDecl=methodIn:andOut::5:10 (variadic) [Bycopy,] [type=] [typekind=Invalid] [resulttype=id] [resulttypekind=ObjCId] [args= [int] [Int] [short *] [Pointer]] [isPOD=0]
 // CHECK: ParmDecl=i:5:27 (Definition) [In,] [type=int] [typekind=Int] [isPOD=1]
 // CHECK: ParmDecl=j:5:49 (Definition) [Out,] [type=short *] [typekind=Pointer] [isPOD=1] [pointeetype=short] [pointeekind=Short]
-// CHECK: ParmDecl=p:6:36 (Definition) [type=__kindof Foo *] [typekind=ObjCObjectPointer] [canonicaltype=__kindof Foo *] [canonicaltypekind=ObjCObjectPointer] [basetype=Foo] [basekind=ObjCInterface] [isPOD=1] [pointeetype=Foo] [pointeekind=ObjCInterface]
+// CHECK: ParmDecl=p:6:36 (Definition) [type=__kindof Foo *] [typekind=ObjCObjectPointer] [canonicaltype=__kindof Foo *] [canonicaltypekind=ObjCObjectPointer] [basetype=Foo] [basekind=ObjCInterface] [isPOD=1] [pointeetype=__kindof Foo] [pointeekind=ObjCObject]
 // CHECK: ObjCPropertyDecl=classProp:7:23 [class,] [type=int] [typekind=Int] [isPOD=1]
 // CHECK: ObjCInstanceMethodDecl=generic:11:12 [type=] [typekind=Invalid] [resulttype=SomeType] [resulttypekind=ObjCTypeParam] [isPOD=0]

clang/tools/libclang/CXType.cpp

@@ -128,7 +128,9 @@ CXType cxtype::MakeCXType(QualType T, CXTranslationUnit TU) {
     // Handle attributed types as the original type
     if (auto *ATT = T->getAs<AttributedType>()) {
       if (!(TU->ParsingOptions & CXTranslationUnit_IncludeAttributedTypes)) {
-        return MakeCXType(ATT->getModifiedType(), TU);
+        // Return the equivalent type which represents the canonically
+        // equivalent type.
+        return MakeCXType(ATT->getEquivalentType(), TU);
       }
     }
     // Handle paren types as the original type