3 files changed, 87 insertions, 0 deletions

diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index 5c7c0694a04..2f167eedd15 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -24,6 +24,7 @@
 #include "clang/AST/ASTMutationListener.h"
 #include "clang/Basic/Builtins.h"
 #include "clang/Basic/IdentifierTable.h"
+#include "clang/Basic/Module.h"
 #include "clang/Basic/Specifiers.h"
 #include "clang/Basic/TargetInfo.h"
 #include "llvm/Support/ErrorHandling.h"
@@ -2609,3 +2610,81 @@ FileScopeAsmDecl *FileScopeAsmDecl::Create(ASTContext &C, DeclContext *DC,
                                            SourceLocation RParenLoc) {
   return new (C) FileScopeAsmDecl(DC, Str, AsmLoc, RParenLoc);
 }
+
+//===----------------------------------------------------------------------===//
+// ImportDecl Implementation
+//===----------------------------------------------------------------------===//
+
+/// \brief Retrieve the number of module identifiers needed to name the given
+/// module.
+static unsigned getNumModuleIdentifiers(Module *Mod) {
+  unsigned Result = 1;
+  while (Mod->Parent) {
+    Mod = Mod->Parent;
+    ++Result;
+  }
+  return Result;
+}
+
+ImportDecl::ImportDecl(DeclContext *DC, SourceLocation ImportLoc, 
+                       Module *Imported,
+                       ArrayRef<SourceLocation> IdentifierLocs)
+  : Decl(Import, DC, ImportLoc), ImportedAndComplete(Imported, true)
+{
+  assert(getNumModuleIdentifiers(Imported) == IdentifierLocs.size());
+  SourceLocation *StoredLocs = reinterpret_cast<SourceLocation *>(this + 1);
+  memcpy(StoredLocs, IdentifierLocs.data(), 
+         IdentifierLocs.size() * sizeof(SourceLocation));
+}
+
+ImportDecl::ImportDecl(DeclContext *DC, SourceLocation ImportLoc, 
+                       Module *Imported, SourceLocation EndLoc)
+  : Decl(Import, DC, ImportLoc), ImportedAndComplete(Imported, false)
+{
+  *reinterpret_cast<SourceLocation *>(this + 1) = EndLoc;
+}
+
+ImportDecl *ImportDecl::Create(ASTContext &C, DeclContext *DC, 
+                               SourceLocation ImportLoc, Module *Imported,
+                               ArrayRef<SourceLocation> IdentifierLocs) {
+  void *Mem = C.Allocate(sizeof(ImportDecl) + 
+                         IdentifierLocs.size() * sizeof(SourceLocation));
+  return new (Mem) ImportDecl(DC, ImportLoc, Imported, IdentifierLocs);
+}
+
+ImportDecl *ImportDecl::CreateImplicit(ASTContext &C, DeclContext *DC, 
+                                       SourceLocation ImportLoc,
+                                       Module *Imported, 
+                                       SourceLocation EndLoc) {
+  void *Mem = C.Allocate(sizeof(ImportDecl) + sizeof(SourceLocation));
+  ImportDecl *Import
+    = new (Mem) ImportDecl(DC, ImportLoc, Imported, 
+                           ArrayRef<SourceLocation>(&EndLoc, 1));
+  Import->setImplicit();
+  return Import;
+}
+
+ImportDecl *ImportDecl::CreateEmpty(ASTContext &C, unsigned NumLocations) {
+  void *Mem = C.Allocate(sizeof(ImportDecl) + 
+                         NumLocations * sizeof(SourceLocation));
+  return new (Mem) ImportDecl(EmptyShell());  
+}
+
+ArrayRef<SourceLocation> ImportDecl::getIdentifierLocs() const {
+  if (!ImportedAndComplete.getInt())
+    return ArrayRef<SourceLocation>();
+
+  const SourceLocation *StoredLocs
+    = reinterpret_cast<const SourceLocation *>(this + 1);
+  return ArrayRef<SourceLocation>(StoredLocs, 
+                                  getNumModuleIdentifiers(getImportedModule()));
+}
+
+SourceRange ImportDecl::getSourceRange() const {
+  if (!ImportedAndComplete.getInt())
+    return SourceRange(getLocation(), 
+                       *reinterpret_cast<const SourceLocation *>(this + 1));
+  
+  return SourceRange(getLocation(), getIdentifierLocs().back());
+}
+
diff --git a/clang/lib/AST/DeclBase.cpp b/clang/lib/AST/DeclBase.cpp
index d892c56f712..f4507e36039 100644
--- a/clang/lib/AST/DeclBase.cpp
+++ b/clang/lib/AST/DeclBase.cpp
@@ -501,6 +501,7 @@ unsigned Decl::getIdentifierNamespaceForKind(Kind DeclKind) {
     case ObjCImplementation:
     case ObjCCategory:
     case ObjCCategoryImpl:
+    case Import:
       // Never looked up by name.
       return 0;
   }
diff --git a/clang/lib/AST/DeclPrinter.cpp b/clang/lib/AST/DeclPrinter.cpp
index e5b4b0431b1..91b011fbda6 100644
--- a/clang/lib/AST/DeclPrinter.cpp
+++ b/clang/lib/AST/DeclPrinter.cpp
@@ -19,6 +19,7 @@
 #include "clang/AST/Expr.h"
 #include "clang/AST/ExprCXX.h"
 #include "clang/AST/PrettyPrinter.h"
+#include "clang/Basic/Module.h"
 #include "llvm/Support/raw_ostream.h"
 using namespace clang;
 
@@ -58,6 +59,7 @@ namespace {
     void VisitLabelDecl(LabelDecl *D);
     void VisitParmVarDecl(ParmVarDecl *D);
     void VisitFileScopeAsmDecl(FileScopeAsmDecl *D);
+    void VisitImportDecl(ImportDecl *D);
     void VisitStaticAssertDecl(StaticAssertDecl *D);
     void VisitNamespaceDecl(NamespaceDecl *D);
     void VisitUsingDirectiveDecl(UsingDirectiveDecl *D);
@@ -646,6 +648,11 @@ void DeclPrinter::VisitFileScopeAsmDecl(FileScopeAsmDecl *D) {
   Out << ")";
 }
 
+void DeclPrinter::VisitImportDecl(ImportDecl *D) {
+  Out << "__import_module__ " << D->getImportedModule()->getFullModuleName()
+      << ";\n";
+}
+
 void DeclPrinter::VisitStaticAssertDecl(StaticAssertDecl *D) {
   Out << "static_assert(";
   D->getAssertExpr()->printPretty(Out, Context, 0, Policy, Indentation);