Introduce a new declaration node, ParamDecl, for function parameters.

Use this node to capture the argument name and its source location in
the AST. We're only building these in one place at the moment; the
rest will be updated soon.


Swift SVN r16581

include/swift/Serialization/ModuleFormat.h

@@ -40,7 +40,7 @@ const uint16_t VERSION_MAJOR = 0;
 /// Serialized module format minor version number.
 ///
 /// When the format changes IN ANY WAY, this number should be incremented.
-const uint16_t VERSION_MINOR = 68;
+const uint16_t VERSION_MINOR = 69;
 
 using DeclID = Fixnum<31>;
 using DeclIDField = BCFixed<31>;
@@ -683,6 +683,16 @@ namespace decls_block {
     DeclIDField   // overridden decl
   >;
 
+  using ParamLayout = BCRecordLayout<
+    PARAM_DECL,
+    IdentifierIDField, // argument name
+    IdentifierIDField, // parameter name
+    DeclIDField,  // context decl
+    BCFixed<1>,   // isLet?
+    TypeIDField,  // type
+    TypeIDField  // interface type
+  >;
+
   using FuncLayout = BCRecordLayout<
     FUNC_DECL,
     DeclIDField,  // context decl
@@ -1018,6 +1028,8 @@ static inline decls_block::RecordKind getKindForTable(const Decl *D) {
     return decls_block::FUNC_DECL;
   case DeclKind::Var:
     return decls_block::VAR_DECL;
+  case DeclKind::Param:
+    return decls_block::PARAM_DECL;
 
   case DeclKind::Subscript:
     return decls_block::SUBSCRIPT_DECL;