Implement the sizeof...(pack) expression to compute the length of a
parameter pack.

Note that we're missing proper libclang support for the new
SizeOfPackExpr expression node.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@122813 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Serialization/ASTReaderStmt.cpp b/lib/Serialization/ASTReaderStmt.cpp
index 4703c63..5ed6f8e 100644
--- a/lib/Serialization/ASTReaderStmt.cpp
+++ b/lib/Serialization/ASTReaderStmt.cpp
@@ -177,6 +177,7 @@
     void VisitBinaryTypeTraitExpr(BinaryTypeTraitExpr *E);
     void VisitCXXNoexceptExpr(CXXNoexceptExpr *E);
     void VisitPackExpansionExpr(PackExpansionExpr *E);
+    void VisitSizeOfPackExpr(SizeOfPackExpr *E);
     
     void VisitOpaqueValueExpr(OpaqueValueExpr *E);
   };
@@ -1294,6 +1295,15 @@
   E->Pattern = Reader.ReadSubExpr();  
 }
 
+void ASTStmtReader::VisitSizeOfPackExpr(SizeOfPackExpr *E) {
+  VisitExpr(E);
+  E->OperatorLoc = ReadSourceLocation(Record, Idx);
+  E->PackLoc = ReadSourceLocation(Record, Idx);
+  E->RParenLoc = ReadSourceLocation(Record, Idx);
+  E->Length = Record[Idx++];
+  E->Pack = cast_or_null<NamedDecl>(Reader.GetDecl(Record[Idx++]));
+}
+
 void ASTStmtReader::VisitOpaqueValueExpr(OpaqueValueExpr *E) {
   VisitExpr(E);
 }
@@ -1820,6 +1830,10 @@
       S = new (Context) PackExpansionExpr(Empty);
       break;
         
+    case EXPR_SIZEOF_PACK:
+      S = new (Context) SizeOfPackExpr(Empty);
+      break;
+        
     case EXPR_OPAQUE_VALUE:
       S = new (Context) OpaqueValueExpr(Empty);
       break;