Major anonymous union/struct redesign.

A new AST node is introduced:
   def IndirectField : DDecl<Value>;
IndirectFields are injected into the anonymous's parent scope and chain back to
the original field. Name lookup for anonymous entities now result in an
IndirectFieldDecl instead of a FieldDecl.
There is no functionality change, the code generated should be the same.

llvm-svn: 119919

2 files changed, 28 insertions, 0 deletions

diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp
index 9f5d0c11d19..b1e46a623e4 100644
--- a/clang/lib/Serialization/ASTReaderDecl.cpp
+++ b/clang/lib/Serialization/ASTReaderDecl.cpp
@@ -107,6 +107,7 @@ namespace clang {
     void VisitCXXDestructorDecl(CXXDestructorDecl *D);
     void VisitCXXConversionDecl(CXXConversionDecl *D);
     void VisitFieldDecl(FieldDecl *FD);
+    void VisitIndirectFieldDecl(IndirectFieldDecl *FD);
     void VisitVarDecl(VarDecl *VD);
     void VisitImplicitParamDecl(ImplicitParamDecl *PD);
     void VisitParmVarDecl(ParmVarDecl *PD);
@@ -635,6 +636,17 @@ void ASTDeclReader::VisitFieldDecl(FieldDecl *FD) {
   }
 }
 
+void ASTDeclReader::VisitIndirectFieldDecl(IndirectFieldDecl *FD) {
+  VisitValueDecl(FD);
+
+  FD->ChainingSize = Record[Idx++];
+  assert(FD->ChainingSize >= 2 && "Anonymous chaining must be >= 2");
+  FD->Chaining = new (*Reader.getContext())NamedDecl*[FD->ChainingSize];
+
+  for (unsigned I = 0; I != FD->ChainingSize; ++I)
+    FD->Chaining[I] = cast<NamedDecl>(Reader.GetDecl(Record[Idx++]));
+}
+
 void ASTDeclReader::VisitVarDecl(VarDecl *VD) {
   VisitDeclaratorDecl(VD);
   VisitRedeclarable(VD);
@@ -1475,6 +1487,10 @@ Decl *ASTReader::ReadDeclRecord(unsigned Index, DeclID ID) {
     D = FieldDecl::Create(*Context, 0, SourceLocation(), 0, QualType(), 0, 0,
                           false);
     break;
+  case DECL_INDIRECTFIELD:
+    D = IndirectFieldDecl::Create(*Context, 0, SourceLocation(), 0, QualType(),
+                                  0, 0);
+    break;
   case DECL_VAR:
     D = VarDecl::Create(*Context, 0, SourceLocation(), 0, QualType(), 0,
                         SC_None, SC_None);
diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp
index f7bb23764da..27adb26d713 100644
--- a/clang/lib/Serialization/ASTWriterDecl.cpp
+++ b/clang/lib/Serialization/ASTWriterDecl.cpp
@@ -72,6 +72,7 @@ namespace clang {
     void VisitCXXDestructorDecl(CXXDestructorDecl *D);
     void VisitCXXConversionDecl(CXXConversionDecl *D);
     void VisitFieldDecl(FieldDecl *D);
+    void VisitIndirectFieldDecl(IndirectFieldDecl *D);
     void VisitVarDecl(VarDecl *D);
     void VisitImplicitParamDecl(ImplicitParamDecl *D);
     void VisitParmVarDecl(ParmVarDecl *D);
@@ -528,6 +529,17 @@ void ASTDeclWriter::VisitFieldDecl(FieldDecl *D) {
   Code = serialization::DECL_FIELD;
 }
 
+void ASTDeclWriter::VisitIndirectFieldDecl(IndirectFieldDecl *D) {
+  VisitValueDecl(D);
+  Record.push_back(D->getChainingSize());
+
+  for (IndirectFieldDecl::chain_iterator
+       P = D->chain_begin(),
+       PEnd = D->chain_end(); P != PEnd; ++P)
+    Writer.AddDeclRef(*P, Record);
+  Code = serialization::DECL_INDIRECTFIELD;
+}
+
 void ASTDeclWriter::VisitVarDecl(VarDecl *D) {
   VisitDeclaratorDecl(D);
   VisitRedeclarable(D);