[Modules] Introduce Module::TopHeaders which is a set of top-level headers

that are associated with a (sub)module.

llvm-svn: 165279

clang/include/clang/Basic/Module.h

@@ -21,6 +21,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/SetVector.h"
 #include <string>
 #include <utility>
 #include <vector>
@@ -72,6 +73,9 @@ public:
   /// \brief The headers that are part of this module.
   llvm::SmallVector<const FileEntry *, 2> Headers;
 
+  /// \brief The top-level headers associated with this module.
+  llvm::SmallSetVector<const FileEntry *, 2> TopHeaders;
+
   /// \brief The set of language features required to use this module.
   ///
   /// If any of these features is not present, the \c IsAvailable bit

clang/include/clang/Serialization/ASTBitCodes.h

@@ -537,16 +537,18 @@ namespace clang {
       SUBMODULE_UMBRELLA_HEADER = 2,
       /// \brief Specifies a header that falls into this (sub)module.
       SUBMODULE_HEADER = 3,
+      /// \brief Specifies a top-level header that falls into this (sub)module.
+      SUBMODULE_TOPHEADER = 4,
       /// \brief Specifies an umbrella directory.
-      SUBMODULE_UMBRELLA_DIR = 4,
+      SUBMODULE_UMBRELLA_DIR = 5,
       /// \brief Specifies the submodules that are imported by this 
       /// submodule.
-      SUBMODULE_IMPORTS = 5,
+      SUBMODULE_IMPORTS = 6,
       /// \brief Specifies the submodules that are re-exported from this 
       /// submodule.
-      SUBMODULE_EXPORTS = 6,
+      SUBMODULE_EXPORTS = 7,
       /// \brief Specifies a required feature.
-      SUBMODULE_REQUIRES = 7
+      SUBMODULE_REQUIRES = 8
     };
 
     /// \brief Record types used within a comments block.

clang/lib/Frontend/FrontendActions.cpp

@@ -132,7 +132,7 @@ ASTConsumer *GenerateModuleAction::CreateASTConsumer(CompilerInstance &CI,
 }
 
 /// \brief Collect the set of header includes needed to construct the given 
-/// module.
+/// module and update the TopHeaders file set of the module.
 ///
 /// \param Module The module we're collecting includes from.
 ///
@@ -149,15 +149,18 @@ static void collectModuleHeaderIncludes(const LangOptions &LangOpts,
 
   // Add includes for each of these headers.
   for (unsigned I = 0, N = Module->Headers.size(); I != N; ++I) {
+    const FileEntry *Header = Module->Headers[I];
+    Module->TopHeaders.insert(Header);
     if (LangOpts.ObjC1)
       Includes += "#import \"";
     else
       Includes += "#include \"";
-    Includes += Module->Headers[I]->getName();
+    Includes += Header->getName();
     Includes += "\"\n";
   }
 
   if (const FileEntry *UmbrellaHeader = Module->getUmbrellaHeader()) {
+    Module->TopHeaders.insert(UmbrellaHeader);
     if (Module->Parent) {
       // Include the umbrella header for submodules.
       if (LangOpts.ObjC1)
@@ -184,9 +187,11 @@ static void collectModuleHeaderIncludes(const LangOptions &LangOpts,
       
       // If this header is marked 'unavailable' in this module, don't include 
       // it.
-      if (const FileEntry *Header = FileMgr.getFile(Dir->path()))
+      if (const FileEntry *Header = FileMgr.getFile(Dir->path())) {
         if (ModMap.isHeaderInUnavailableModule(Header))
           continue;
+        Module->TopHeaders.insert(Header);
+      }
       
       // Include this header umbrella header for submodules.
       if (LangOpts.ObjC1)

clang/lib/Lex/ModuleMap.cpp

@@ -152,6 +152,7 @@ Module *ModuleMap::findModuleForHeader(const FileEntry *File) {
         StringRef Name = llvm::sys::path::stem(File->getName());
         Result = findOrCreateModule(Name, Result, /*IsFramework=*/false,
                                     Explicit).first;
+        Result->TopHeaders.insert(File);
         
         // If inferred submodules export everything they import, add a 
         // wildcard to the set of exports.

clang/lib/Serialization/ASTReader.cpp

@@ -3230,7 +3230,23 @@ ASTReader::ASTReadResult ASTReader::ReadSubmoduleBlock(ModuleFile &F) {
       }
       break;      
     }
-        
+
+    case SUBMODULE_TOPHEADER: {
+      if (First) {
+        Error("missing submodule metadata record at beginning of block");
+        return Failure;
+      }
+
+      if (!CurrentModule)
+        break;
+
+      // FIXME: Be more lazy about this!
+      StringRef FileName(BlobStart, BlobLen);
+      if (const FileEntry *File = PP.getFileManager().getFile(FileName))
+        CurrentModule->TopHeaders.insert(File);
+      break;
+    }
+
     case SUBMODULE_UMBRELLA_DIR: {
       if (First) {
         Error("missing submodule metadata record at beginning of block");

clang/lib/Serialization/ASTWriter.cpp

@@ -1951,6 +1951,11 @@ void ASTWriter::WriteSubmodules(Module *WritingModule) {
   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
   unsigned HeaderAbbrev = Stream.EmitAbbrev(Abbrev);
 
+  Abbrev = new BitCodeAbbrev();
+  Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_TOPHEADER));
+  Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
+  unsigned TopHeaderAbbrev = Stream.EmitAbbrev(Abbrev);
+
   Abbrev = new BitCodeAbbrev();
   Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_UMBRELLA_DIR));
   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
@@ -2022,6 +2027,12 @@ void ASTWriter::WriteSubmodules(Module *WritingModule) {
       Stream.EmitRecordWithBlob(HeaderAbbrev, Record, 
                                 Mod->Headers[I]->getName());
     }
+    for (unsigned I = 0, N = Mod->TopHeaders.size(); I != N; ++I) {
+      Record.clear();
+      Record.push_back(SUBMODULE_TOPHEADER);
+      Stream.EmitRecordWithBlob(TopHeaderAbbrev, Record,
+                                Mod->TopHeaders[I]->getName());
+    }
 
     // Emit the imports. 
     if (!Mod->Imports.empty()) {