[index] Enhance indexing for module references

* Create a USR for the occurrences of the 'module' symbol kind
* Record module references for each identifier in an import declaration

llvm-svn: 342484

3 files changed, 51 insertions, 2 deletions

diff --git a/clang/lib/Index/IndexingAction.cpp b/clang/lib/Index/IndexingAction.cpp
index cb5c951f38a..5cdec4b4528 100644
--- a/clang/lib/Index/IndexingAction.cpp
+++ b/clang/lib/Index/IndexingAction.cpp
@@ -37,6 +37,7 @@ bool IndexDataConsumer::handleMacroOccurence(const IdentifierInfo *Name,
 }
 
 bool IndexDataConsumer::handleModuleOccurence(const ImportDecl *ImportD,
+                                              const Module *Mod,
                                               SymbolRoleSet Roles,
                                               SourceLocation Loc) {
   return true;
diff --git a/clang/lib/Index/IndexingContext.cpp b/clang/lib/Index/IndexingContext.cpp
index 333f9dc3091..bba6c8390b5 100644
--- a/clang/lib/Index/IndexingContext.cpp
+++ b/clang/lib/Index/IndexingContext.cpp
@@ -80,11 +80,27 @@ bool IndexingContext::handleReference(const NamedDecl *D, SourceLocation Loc,
                               RefE, RefD, DC);
 }
 
+static void reportModuleReferences(const Module *Mod,
+                                   ArrayRef<SourceLocation> IdLocs,
+                                   const ImportDecl *ImportD,
+                                   IndexDataConsumer &DataConsumer) {
+  if (!Mod)
+    return;
+  reportModuleReferences(Mod->Parent, IdLocs.drop_back(), ImportD,
+                         DataConsumer);
+  DataConsumer.handleModuleOccurence(ImportD, Mod,
+                                     (SymbolRoleSet)SymbolRole::Reference,
+                                     IdLocs.back());
+}
+
 bool IndexingContext::importedModule(const ImportDecl *ImportD) {
+  if (ImportD->isInvalidDecl())
+    return true;
+
   SourceLocation Loc;
   auto IdLocs = ImportD->getIdentifierLocs();
   if (!IdLocs.empty())
-    Loc = IdLocs.front();
+    Loc = IdLocs.back();
   else
     Loc = ImportD->getLocation();
 
@@ -108,11 +124,17 @@ bool IndexingContext::importedModule(const ImportDecl *ImportD) {
     }
   }
 
+  const Module *Mod = ImportD->getImportedModule();
+  if (!ImportD->isImplicit() && Mod->Parent && !IdLocs.empty()) {
+    reportModuleReferences(Mod->Parent, IdLocs.drop_back(), ImportD,
+                           DataConsumer);
+  }
+
   SymbolRoleSet Roles = (unsigned)SymbolRole::Declaration;
   if (ImportD->isImplicit())
     Roles |= (unsigned)SymbolRole::Implicit;
 
-  return DataConsumer.handleModuleOccurence(ImportD, Roles, Loc);
+  return DataConsumer.handleModuleOccurence(ImportD, Mod, Roles, Loc);
 }
 
 bool IndexingContext::isTemplateImplicitInstantiation(const Decl *D) {
diff --git a/clang/lib/Index/USRGeneration.cpp b/clang/lib/Index/USRGeneration.cpp
index 62ae7108fc6..8194c9508fb 100644
--- a/clang/lib/Index/USRGeneration.cpp
+++ b/clang/lib/Index/USRGeneration.cpp
@@ -1094,3 +1094,29 @@ bool clang::index::generateUSRForMacro(StringRef MacroName, SourceLocation Loc,
   Out << MacroName;
   return false;
 }
+
+bool clang::index::generateFullUSRForModule(const Module *Mod,
+                                            raw_ostream &OS) {
+  if (!Mod->Parent)
+    return generateFullUSRForTopLevelModuleName(Mod->Name, OS);
+  if (generateFullUSRForModule(Mod->Parent, OS))
+    return true;
+  return generateUSRFragmentForModule(Mod, OS);
+}
+
+bool clang::index::generateFullUSRForTopLevelModuleName(StringRef ModName,
+                                                        raw_ostream &OS) {
+  OS << getUSRSpacePrefix();
+  return generateUSRFragmentForModuleName(ModName, OS);
+}
+
+bool clang::index::generateUSRFragmentForModule(const Module *Mod,
+                                                raw_ostream &OS) {
+  return generateUSRFragmentForModuleName(Mod->Name, OS);
+}
+
+bool clang::index::generateUSRFragmentForModuleName(StringRef ModName,
+                                                    raw_ostream &OS) {
+  OS << "@M@" << ModName;
+  return false;
+}