Revert "Revert "PR14606: Debug info for using directives/DW_TAG_imported_module""

This reverts commit 179839 now that the corresponding LLVM patch has been fixed.

llvm-svn: 179997

4 files changed, 25 insertions, 3 deletions

diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 45692312e0c..6beba66c79a 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -2929,6 +2929,13 @@ void CGDebugInfo::EmitGlobalVariable(const ValueDecl *VD,
                                 getStaticDataMemberDeclaration(VD));
 }
 
+void CGDebugInfo::EmitUsingDirective(const UsingDirectiveDecl &UD) {
+  DBuilder.createImportedModule(
+      getContextDescriptor(cast<Decl>(UD.getDeclContext())),
+      getOrCreateNameSpace(UD.getNominatedNamespace()),
+      getLineNumber(UD.getLocation()));
+}
+
 /// getOrCreateNamesSpace - Return namespace descriptor for the given
 /// namespace decl.
 llvm::DINameSpace 
diff --git a/clang/lib/CodeGen/CGDebugInfo.h b/clang/lib/CodeGen/CGDebugInfo.h
index 060b7380580..4080492a1c6 100644
--- a/clang/lib/CodeGen/CGDebugInfo.h
+++ b/clang/lib/CodeGen/CGDebugInfo.h
@@ -262,6 +262,9 @@ public:
   /// EmitGlobalVariable - Emit global variable's debug info.
   void EmitGlobalVariable(const ValueDecl *VD, llvm::Constant *Init);
 
+  /// \brief - Emit C++ using directive.
+  void EmitUsingDirective(const UsingDirectiveDecl &UD);
+
   /// getOrCreateRecordType - Emit record type's standalone debug info. 
   llvm::DIType getOrCreateRecordType(QualType Ty, SourceLocation L);
 
diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp
index 9ad9cf022cb..3ce6dec6a53 100644
--- a/clang/lib/CodeGen/CGDecl.cpp
+++ b/clang/lib/CodeGen/CGDecl.cpp
@@ -80,7 +80,6 @@ void CodeGenFunction::EmitDecl(const Decl &D) {
   case Decl::CXXRecord: // struct/union/class X; [C++]
   case Decl::Using:          // using X; [C++]
   case Decl::UsingShadow:
-  case Decl::UsingDirective: // using namespace X; [C++]
   case Decl::NamespaceAlias:
   case Decl::StaticAssert: // static_assert(X, ""); [C++0x]
   case Decl::Label:        // __label__ x;
@@ -90,6 +89,10 @@ void CodeGenFunction::EmitDecl(const Decl &D) {
     // None of these decls require codegen support.
     return;
 
+  case Decl::UsingDirective: // using namespace X; [C++]
+    if (CGDebugInfo *DI = getDebugInfo())
+      DI->EmitUsingDirective(cast<UsingDirectiveDecl>(D));
+    return;
   case Decl::Var: {
     const VarDecl &VD = cast<VarDecl>(D);
     assert(VD.isLocalVarDecl() &&
diff --git a/clang/test/CodeGenCXX/debug-info-namespace.cpp b/clang/test/CodeGenCXX/debug-info-namespace.cpp
index 262e996d44d..89dd6d947f7 100644
--- a/clang/test/CodeGenCXX/debug-info-namespace.cpp
+++ b/clang/test/CodeGenCXX/debug-info-namespace.cpp
@@ -7,11 +7,20 @@ int i;
 }
 }
 
+int func() {
+  using namespace A::B;
+  return i;
+}
+
+// CHECK: [[MODULES:![0-9]*]], metadata !""} ; [ DW_TAG_compile_unit ]
 // CHECK: [[FILE:![0-9]*]] {{.*}}debug-info-namespace.cpp"
+// CHECK: [[FUNC:![0-9]*]] {{.*}} ; [ DW_TAG_subprogram ] [line 6] [def] [func]
+// CHECK: [[FILE2:![0-9]*]]} ; [ DW_TAG_file_type ] [{{.*}}foo.cpp]
 // CHECK: [[VAR:![0-9]*]] = {{.*}}, metadata [[NS:![0-9]*]], metadata !"i", {{.*}} ; [ DW_TAG_variable ] [i]
-// CHECK: [[NS]] = {{.*}}, metadata [[FILE2:![0-9]*]], metadata [[CTXT:![0-9]*]], {{.*}} ; [ DW_TAG_namespace ] [B] [line 1]
+// CHECK: [[NS]] = {{.*}}, metadata [[FILE2]], metadata [[CTXT:![0-9]*]], {{.*}} ; [ DW_TAG_namespace ] [B] [line 1]
 // CHECK: [[CTXT]] = {{.*}}, metadata [[FILE]], null, {{.*}} ; [ DW_TAG_namespace ] [A] [line 3]
-// CHECK: [[FILE2]]} ; [ DW_TAG_file_type ] [{{.*}}foo.cpp]
+// CHECK: [[MODULES]] = metadata !{metadata [[MODULE:![0-9]*]]}
+// CHECK: [[MODULE]] = metadata !{i32 {{[0-9]*}}, metadata [[FUNC]], metadata [[NS]], i32 7} ; [ DW_TAG_imported_module ]
 
 // FIXME: It is confused on win32 to generate file entry when dosish filename is given.
 // REQUIRES: shell