Implement support for pack expansions whose pattern is a non-type

template argument (described by an expression, of course). For
example:

  template<int...> struct int_tuple { };

  template<int ...Values>
  struct square {
    typedef int_tuple<(Values*Values)...> type;
  };

It also lays the foundation for pack expansions in an initializer-list.
  

llvm-svn: 122751

2 files changed, 20 insertions, 2 deletions

diff --git a/clang/lib/Serialization/ASTReaderStmt.cpp b/clang/lib/Serialization/ASTReaderStmt.cpp
index aa669b34b3d..4703c633fbe 100644
--- a/clang/lib/Serialization/ASTReaderStmt.cpp
+++ b/clang/lib/Serialization/ASTReaderStmt.cpp
@@ -176,7 +176,8 @@ namespace clang {
     void VisitUnaryTypeTraitExpr(UnaryTypeTraitExpr *E);
     void VisitBinaryTypeTraitExpr(BinaryTypeTraitExpr *E);
     void VisitCXXNoexceptExpr(CXXNoexceptExpr *E);
-
+    void VisitPackExpansionExpr(PackExpansionExpr *E);
+    
     void VisitOpaqueValueExpr(OpaqueValueExpr *E);
   };
 }
@@ -1287,6 +1288,12 @@ void ASTStmtReader::VisitCXXNoexceptExpr(CXXNoexceptExpr *E) {
   E->Operand = Reader.ReadSubExpr();
 }
 
+void ASTStmtReader::VisitPackExpansionExpr(PackExpansionExpr *E) {
+  VisitExpr(E);
+  E->EllipsisLoc = ReadSourceLocation(Record, Idx);
+  E->Pattern = Reader.ReadSubExpr();  
+}
+
 void ASTStmtReader::VisitOpaqueValueExpr(OpaqueValueExpr *E) {
   VisitExpr(E);
 }
@@ -1809,6 +1816,10 @@ Stmt *ASTReader::ReadStmtFromStream(PerFileData &F) {
       S = new (Context) CXXNoexceptExpr(Empty);
       break;
 
+    case EXPR_PACK_EXPANSION:
+      S = new (Context) PackExpansionExpr(Empty);
+      break;
+        
     case EXPR_OPAQUE_VALUE:
       S = new (Context) OpaqueValueExpr(Empty);
       break;
diff --git a/clang/lib/Serialization/ASTWriterStmt.cpp b/clang/lib/Serialization/ASTWriterStmt.cpp
index 89c293fe6ca..27261dbb2a9 100644
--- a/clang/lib/Serialization/ASTWriterStmt.cpp
+++ b/clang/lib/Serialization/ASTWriterStmt.cpp
@@ -150,7 +150,7 @@ namespace clang {
     void VisitUnaryTypeTraitExpr(UnaryTypeTraitExpr *E);
     void VisitBinaryTypeTraitExpr(BinaryTypeTraitExpr *E);
     void VisitCXXNoexceptExpr(CXXNoexceptExpr *E);
-
+    void VisitPackExpansionExpr(PackExpansionExpr *E);
     void VisitOpaqueValueExpr(OpaqueValueExpr *E);
   };
 }
@@ -1296,6 +1296,13 @@ void ASTStmtWriter::VisitCXXNoexceptExpr(CXXNoexceptExpr *E) {
   Code = serialization::EXPR_CXX_NOEXCEPT;
 }
 
+void ASTStmtWriter::VisitPackExpansionExpr(PackExpansionExpr *E) {
+  VisitExpr(E);
+  Writer.AddSourceLocation(E->getEllipsisLoc(), Record);
+  Writer.AddStmt(E->getPattern());
+  Code = serialization::EXPR_PACK_EXPANSION;
+}
+
 void ASTStmtWriter::VisitOpaqueValueExpr(OpaqueValueExpr *E) {
   VisitExpr(E);
   Code = serialization::EXPR_OPAQUE_VALUE;