1 files changed, 431 insertions, 85 deletions

diff --git a/contrib/llvm/tools/clang/lib/Lex/HeaderSearch.cpp b/contrib/llvm/tools/clang/lib/Lex/HeaderSearch.cpp
index 931145a..d688e23 100644
--- a/contrib/llvm/tools/clang/lib/Lex/HeaderSearch.cpp
+++ b/contrib/llvm/tools/clang/lib/Lex/HeaderSearch.cpp
@@ -13,6 +13,8 @@
 
 #include "clang/Lex/HeaderSearch.h"
 #include "clang/Lex/HeaderMap.h"
+#include "clang/Lex/Lexer.h"
+#include "clang/Basic/Diagnostic.h"
 #include "clang/Basic/FileManager.h"
 #include "clang/Basic/IdentifierTable.h"
 #include "llvm/Support/FileSystem.h"
@@ -36,8 +38,12 @@ HeaderFileInfo::getControllingMacro(ExternalIdentifierLookup *External) {
 
 ExternalHeaderFileInfoSource::~ExternalHeaderFileInfoSource() {}
 
-HeaderSearch::HeaderSearch(FileManager &FM)
-    : FileMgr(FM), FrameworkMap(64) {
+HeaderSearch::HeaderSearch(FileManager &FM, DiagnosticsEngine &Diags,
+                           const LangOptions &LangOpts, 
+                           const TargetInfo *Target)
+  : FileMgr(FM), Diags(Diags), FrameworkMap(64), 
+    ModMap(FileMgr, *Diags.getClient(), LangOpts, Target)
+{
   AngledDirIdx = 0;
   SystemDirIdx = 0;
   NoCurDirSearch = false;
@@ -98,58 +104,81 @@ const HeaderMap *HeaderSearch::CreateHeaderMap(const FileEntry *FE) {
   return 0;
 }
 
-const FileEntry *HeaderSearch::lookupModule(StringRef ModuleName,
-                                            std::string *ModuleFileName,
-                                            std::string *UmbrellaHeader) {
+std::string HeaderSearch::getModuleFileName(Module *Module) {
   // If we don't have a module cache path, we can't do anything.
-  if (ModuleCachePath.empty()) {
-    if (ModuleFileName)
-      ModuleFileName->clear();
-    return 0;
-  }
+  if (ModuleCachePath.empty()) 
+    return std::string();
+
+
+  SmallString<256> Result(ModuleCachePath);
+  llvm::sys::path::append(Result, Module->getTopLevelModule()->Name + ".pcm");
+  return Result.str().str();
+}
+
+std::string HeaderSearch::getModuleFileName(StringRef ModuleName) {
+  // If we don't have a module cache path, we can't do anything.
+  if (ModuleCachePath.empty()) 
+    return std::string();
   
-  // Try to find the module path.
-  llvm::SmallString<256> FileName(ModuleCachePath);
-  llvm::sys::path::append(FileName, ModuleName + ".pcm");
-  if (ModuleFileName)
-    *ModuleFileName = FileName.str();
-    
-  if (const FileEntry *ModuleFile
-        = getFileMgr().getFile(FileName, /*OpenFile=*/false,
-                               /*CacheFailure=*/false))
-    return ModuleFile;
   
-  // We didn't find the module. If we're not supposed to look for an
-  // umbrella header, this is the end of the road.
-  if (!UmbrellaHeader)
-    return 0;
+  SmallString<256> Result(ModuleCachePath);
+  llvm::sys::path::append(Result, ModuleName + ".pcm");
+  return Result.str().str();
+}
+
+Module *HeaderSearch::lookupModule(StringRef ModuleName, bool AllowSearch) {
+  // Look in the module map to determine if there is a module by this name.
+  Module *Module = ModMap.findModule(ModuleName);
+  if (Module || !AllowSearch)
+    return Module;
   
-  // Look in each of the framework directories for an umbrella header with
-  // the same name as the module.
-  // FIXME: We need a way for non-frameworks to provide umbrella headers.
-  llvm::SmallString<128> UmbrellaHeaderName;
-  UmbrellaHeaderName = ModuleName;
-  UmbrellaHeaderName += '/';
-  UmbrellaHeaderName += ModuleName;
-  UmbrellaHeaderName += ".h";
+  // Look through the various header search paths to load any avai;able module 
+  // maps, searching for a module map that describes this module.
   for (unsigned Idx = 0, N = SearchDirs.size(); Idx != N; ++Idx) {
-    // Skip non-framework include paths
-    if (!SearchDirs[Idx].isFramework())
+    if (SearchDirs[Idx].isFramework()) {
+      // Search for or infer a module map for a framework.
+      SmallString<128> FrameworkDirName;
+      FrameworkDirName += SearchDirs[Idx].getFrameworkDir()->getName();
+      llvm::sys::path::append(FrameworkDirName, ModuleName + ".framework");
+      if (const DirectoryEntry *FrameworkDir 
+            = FileMgr.getDirectory(FrameworkDirName)) {
+        bool IsSystem
+          = SearchDirs[Idx].getDirCharacteristic() != SrcMgr::C_User;
+        Module = loadFrameworkModule(ModuleName, FrameworkDir, IsSystem);
+        if (Module)
+          break;
+      }
+    }
+    
+    // FIXME: Figure out how header maps and module maps will work together.
+    
+    // Only deal with normal search directories.
+    if (!SearchDirs[Idx].isNormalDir())
       continue;
     
-    // Look for the umbrella header in this directory.
-    if (const FileEntry *HeaderFile
-          = SearchDirs[Idx].LookupFile(UmbrellaHeaderName, *this, 0, 0, 
-                                       StringRef(), 0)) {
-      *UmbrellaHeader = HeaderFile->getName();
-      return 0;
+    // Search for a module map file in this directory.
+    if (loadModuleMapFile(SearchDirs[Idx].getDir()) == LMM_NewlyLoaded) {
+      // We just loaded a module map file; check whether the module is
+      // available now.
+      Module = ModMap.findModule(ModuleName);
+      if (Module)
+        break;
+    }
+              
+    // Search for a module map in a subdirectory with the same name as the
+    // module.
+    SmallString<128> NestedModuleMapDirName;
+    NestedModuleMapDirName = SearchDirs[Idx].getDir()->getName();
+    llvm::sys::path::append(NestedModuleMapDirName, ModuleName);
+    if (loadModuleMapFile(NestedModuleMapDirName) == LMM_NewlyLoaded) {
+      // If we just loaded a module map file, look for the module again.
+      Module = ModMap.findModule(ModuleName);
+      if (Module)
+        break;
     }
   }
   
-  // We did not find an umbrella header. Clear out the UmbrellaHeader pointee
-  // so our caller knows that we failed.
-  UmbrellaHeader->clear();
-  return 0;
+  return Module;
 }
 
 //===----------------------------------------------------------------------===//
@@ -175,9 +204,11 @@ const FileEntry *DirectoryLookup::LookupFile(
     HeaderSearch &HS,
     SmallVectorImpl<char> *SearchPath,
     SmallVectorImpl<char> *RelativePath,
-    StringRef BuildingModule,
-    StringRef *SuggestedModule) const {
-  llvm::SmallString<1024> TmpDir;
+    Module **SuggestedModule,
+    bool &InUserSpecifiedSystemFramework) const {
+  InUserSpecifiedSystemFramework = false;
+
+  SmallString<1024> TmpDir;
   if (isNormalDir()) {
     // Concatenate the requested file onto the directory.
     TmpDir = getDir()->getName();
@@ -191,12 +222,27 @@ const FileEntry *DirectoryLookup::LookupFile(
       RelativePath->clear();
       RelativePath->append(Filename.begin(), Filename.end());
     }
+    
+    // If we have a module map that might map this header, load it and
+    // check whether we'll have a suggestion for a module.
+    if (SuggestedModule && HS.hasModuleMap(TmpDir, getDir())) {
+      const FileEntry *File = HS.getFileMgr().getFile(TmpDir.str(), 
+                                                      /*openFile=*/false);
+      if (!File)
+        return File;
+      
+      // If there is a module that corresponds to this header, 
+      // suggest it.
+      *SuggestedModule = HS.findModuleForHeader(File);
+      return File;
+    }
+    
     return HS.getFileMgr().getFile(TmpDir.str(), /*openFile=*/true);
   }
 
   if (isFramework())
     return DoFrameworkLookup(Filename, HS, SearchPath, RelativePath,
-                             BuildingModule, SuggestedModule);
+                             SuggestedModule, InUserSpecifiedSystemFramework);
 
   assert(isHeaderMap() && "Unknown directory lookup");
   const FileEntry * const Result = getHeaderMap()->LookupFile(
@@ -223,8 +269,8 @@ const FileEntry *DirectoryLookup::DoFrameworkLookup(
     HeaderSearch &HS,
     SmallVectorImpl<char> *SearchPath,
     SmallVectorImpl<char> *RelativePath,
-    StringRef BuildingModule,
-    StringRef *SuggestedModule) const 
+    Module **SuggestedModule,
+    bool &InUserSpecifiedSystemFramework) const
 {
   FileManager &FileMgr = HS.getFileMgr();
 
@@ -233,49 +279,71 @@ const FileEntry *DirectoryLookup::DoFrameworkLookup(
   if (SlashPos == StringRef::npos) return 0;
 
   // Find out if this is the home for the specified framework, by checking
-  // HeaderSearch.  Possible answer are yes/no and unknown.
-  const DirectoryEntry *&FrameworkDirCache =
+  // HeaderSearch.  Possible answers are yes/no and unknown.
+  HeaderSearch::FrameworkCacheEntry &CacheEntry =
     HS.LookupFrameworkCache(Filename.substr(0, SlashPos));
 
   // If it is known and in some other directory, fail.
-  if (FrameworkDirCache && FrameworkDirCache != getFrameworkDir())
+  if (CacheEntry.Directory && CacheEntry.Directory != getFrameworkDir())
     return 0;
 
   // Otherwise, construct the path to this framework dir.
 
   // FrameworkName = "/System/Library/Frameworks/"
-  llvm::SmallString<1024> FrameworkName;
+  SmallString<1024> FrameworkName;
   FrameworkName += getFrameworkDir()->getName();
   if (FrameworkName.empty() || FrameworkName.back() != '/')
     FrameworkName.push_back('/');
 
   // FrameworkName = "/System/Library/Frameworks/Cocoa"
-  FrameworkName.append(Filename.begin(), Filename.begin()+SlashPos);
+  StringRef ModuleName(Filename.begin(), SlashPos);
+  FrameworkName += ModuleName;
 
   // FrameworkName = "/System/Library/Frameworks/Cocoa.framework/"
   FrameworkName += ".framework/";
 
-  // If the cache entry is still unresolved, query to see if the cache entry is
-  // still unresolved.  If so, check its existence now.
-  if (FrameworkDirCache == 0) {
+  // If the cache entry was unresolved, populate it now.
+  if (CacheEntry.Directory == 0) {
     HS.IncrementFrameworkLookupCount();
 
     // If the framework dir doesn't exist, we fail.
-    // FIXME: It's probably more efficient to query this with FileMgr.getDir.
-    bool Exists;
-    if (llvm::sys::fs::exists(FrameworkName.str(), Exists) || !Exists)
-      return 0;
+    const DirectoryEntry *Dir = FileMgr.getDirectory(FrameworkName.str());
+    if (Dir == 0) return 0;
 
     // Otherwise, if it does, remember that this is the right direntry for this
     // framework.
-    FrameworkDirCache = getFrameworkDir();
+    CacheEntry.Directory = getFrameworkDir();
+
+    // If this is a user search directory, check if the framework has been
+    // user-specified as a system framework.
+    if (getDirCharacteristic() == SrcMgr::C_User) {
+      SmallString<1024> SystemFrameworkMarker(FrameworkName);
+      SystemFrameworkMarker += ".system_framework";
+      if (llvm::sys::fs::exists(SystemFrameworkMarker.str())) {
+        CacheEntry.IsUserSpecifiedSystemFramework = true;
+      }
+    }
   }
 
+  // Set the 'user-specified system framework' flag.
+  InUserSpecifiedSystemFramework = CacheEntry.IsUserSpecifiedSystemFramework;
+
   if (RelativePath != NULL) {
     RelativePath->clear();
     RelativePath->append(Filename.begin()+SlashPos+1, Filename.end());
   }
 
+  // If we're allowed to look for modules, try to load or create the module
+  // corresponding to this framework.
+  Module *Module = 0;
+  if (SuggestedModule) {
+    if (const DirectoryEntry *FrameworkDir
+                                        = FileMgr.getDirectory(FrameworkName)) {
+      bool IsSystem = getDirCharacteristic() != SrcMgr::C_User;
+      Module = HS.loadFrameworkModule(ModuleName, FrameworkDir, IsSystem);
+    }
+  }
+  
   // Check "/System/Library/Frameworks/Cocoa.framework/Headers/file.h"
   unsigned OrigSize = FrameworkName.size();
 
@@ -287,16 +355,13 @@ const FileEntry *DirectoryLookup::DoFrameworkLookup(
     SearchPath->append(FrameworkName.begin(), FrameworkName.end()-1);
   }
 
-  /// Determine whether this is the module we're building or not.
-  bool AutomaticImport = SuggestedModule &&
-    (BuildingModule != StringRef(Filename.begin(), SlashPos)) &&
-    !Filename.substr(SlashPos + 1).startswith("..");
-  
+  // Determine whether this is the module we're building or not.
+  bool AutomaticImport = Module;  
   FrameworkName.append(Filename.begin()+SlashPos+1, Filename.end());
   if (const FileEntry *FE = FileMgr.getFile(FrameworkName.str(),
                                             /*openFile=*/!AutomaticImport)) {
     if (AutomaticImport)
-      *SuggestedModule = StringRef(Filename.begin(), SlashPos);
+      *SuggestedModule = HS.findModuleForHeader(FE);
     return FE;
   }
 
@@ -311,10 +376,14 @@ const FileEntry *DirectoryLookup::DoFrameworkLookup(
   const FileEntry *FE = FileMgr.getFile(FrameworkName.str(), 
                                         /*openFile=*/!AutomaticImport);
   if (FE && AutomaticImport)
-    *SuggestedModule = StringRef(Filename.begin(), SlashPos);
+    *SuggestedModule = HS.findModuleForHeader(FE);
   return FE;
 }
 
+void HeaderSearch::setTarget(const TargetInfo &Target) {
+  ModMap.setTarget(Target);
+}
+
 
 //===----------------------------------------------------------------------===//
 // Header File Location.
@@ -334,10 +403,11 @@ const FileEntry *HeaderSearch::LookupFile(
     const FileEntry *CurFileEnt,
     SmallVectorImpl<char> *SearchPath,
     SmallVectorImpl<char> *RelativePath,
-    StringRef *SuggestedModule) 
+    Module **SuggestedModule,
+    bool SkipCache)
 {
   if (SuggestedModule)
-    *SuggestedModule = StringRef();
+    *SuggestedModule = 0;
     
   // If 'Filename' is absolute, check to see if it exists and no searching.
   if (llvm::sys::path::is_absolute(Filename)) {
@@ -362,7 +432,7 @@ const FileEntry *HeaderSearch::LookupFile(
   // a subsequent include of "baz.h" should resolve to "whatever/foo/baz.h".
   // This search is not done for <> headers.
   if (CurFileEnt && !isAngled && !NoCurDirSearch) {
-    llvm::SmallString<1024> TmpDir;
+    SmallString<1024> TmpDir;
     // Concatenate the requested file onto the directory.
     // FIXME: Portability.  Filename concatenation should be in sys::Path.
     TmpDir += CurFileEnt->getDir()->getName();
@@ -410,7 +480,7 @@ const FileEntry *HeaderSearch::LookupFile(
   // If the entry has been previously looked up, the first value will be
   // non-zero.  If the value is equal to i (the start point of our search), then
   // this is a matching hit.
-  if (CacheLookup.first == i+1) {
+  if (!SkipCache && CacheLookup.first == i+1) {
     // Skip querying potentially lots of directories for this lookup.
     i = CacheLookup.second;
   } else {
@@ -422,9 +492,10 @@ const FileEntry *HeaderSearch::LookupFile(
 
   // Check each directory in sequence to see if it contains this file.
   for (; i != SearchDirs.size(); ++i) {
+    bool InUserSpecifiedSystemFramework = false;
     const FileEntry *FE =
       SearchDirs[i].LookupFile(Filename, *this, SearchPath, RelativePath,
-                               BuildingModule, SuggestedModule);
+                               SuggestedModule, InUserSpecifiedSystemFramework);
     if (!FE) continue;
 
     CurDir = &SearchDirs[i];
@@ -433,6 +504,12 @@ const FileEntry *HeaderSearch::LookupFile(
     HeaderFileInfo &HFI = getFileInfo(FE);
     HFI.DirInfo = CurDir->getDirCharacteristic();
 
+    // If the directory characteristic is User but this framework was
+    // user-specified to be treated as a system framework, promote the
+    // characteristic.
+    if (HFI.DirInfo == SrcMgr::C_User && InUserSpecifiedSystemFramework)
+      HFI.DirInfo = SrcMgr::C_System;
+
     // If this file is found in a header map and uses the framework style of
     // includes, then this header is part of a framework we're building.
     if (CurDir->isIndexHeaderMap()) {
@@ -456,7 +533,7 @@ const FileEntry *HeaderSearch::LookupFile(
   if (CurFileEnt && !isAngled && Filename.find('/') == StringRef::npos) {
     HeaderFileInfo &IncludingHFI = getFileInfo(CurFileEnt);
     if (IncludingHFI.IndexHeaderMapHeader) {
-      llvm::SmallString<128> ScratchFilename;
+      SmallString<128> ScratchFilename;
       ScratchFilename += IncludingHFI.Framework;
       ScratchFilename += '/';
       ScratchFilename += Filename;
@@ -491,6 +568,7 @@ LookupSubframeworkHeader(StringRef Filename,
   assert(ContextFileEnt && "No context file?");
 
   // Framework names must have a '/' in the filename.  Find it.
+  // FIXME: Should we permit '\' on Windows?
   size_t SlashPos = Filename.find('/');
   if (SlashPos == StringRef::npos) return 0;
 
@@ -498,30 +576,32 @@ LookupSubframeworkHeader(StringRef Filename,
   const char *ContextName = ContextFileEnt->getName();
 
   // If the context info wasn't a framework, couldn't be a subframework.
-  const char *FrameworkPos = strstr(ContextName, ".framework/");
-  if (FrameworkPos == 0)
+  const unsigned DotFrameworkLen = 10;
+  const char *FrameworkPos = strstr(ContextName, ".framework");
+  if (FrameworkPos == 0 || 
+      (FrameworkPos[DotFrameworkLen] != '/' && 
+       FrameworkPos[DotFrameworkLen] != '\\'))
     return 0;
 
-  llvm::SmallString<1024> FrameworkName(ContextName,
-                                        FrameworkPos+strlen(".framework/"));
+  SmallString<1024> FrameworkName(ContextName, FrameworkPos+DotFrameworkLen+1);
 
   // Append Frameworks/HIToolbox.framework/
   FrameworkName += "Frameworks/";
   FrameworkName.append(Filename.begin(), Filename.begin()+SlashPos);
   FrameworkName += ".framework/";
 
-  llvm::StringMapEntry<const DirectoryEntry *> &CacheLookup =
+  llvm::StringMapEntry<FrameworkCacheEntry> &CacheLookup =
     FrameworkMap.GetOrCreateValue(Filename.substr(0, SlashPos));
 
   // Some other location?
-  if (CacheLookup.getValue() &&
+  if (CacheLookup.getValue().Directory &&
       CacheLookup.getKeyLength() == FrameworkName.size() &&
       memcmp(CacheLookup.getKeyData(), &FrameworkName[0],
              CacheLookup.getKeyLength()) != 0)
     return 0;
 
   // Cache subframework.
-  if (CacheLookup.getValue() == 0) {
+  if (CacheLookup.getValue().Directory == 0) {
     ++NumSubFrameworkLookups;
 
     // If the framework dir doesn't exist, we fail.
@@ -530,7 +610,7 @@ LookupSubframeworkHeader(StringRef Filename,
 
     // Otherwise, if it does, remember that this is the right direntry for this
     // framework.
-    CacheLookup.setValue(Dir);
+    CacheLookup.getValue().Directory = Dir;
   }
 
   const FileEntry *FE = 0;
@@ -541,7 +621,7 @@ LookupSubframeworkHeader(StringRef Filename,
   }
 
   // Check ".../Frameworks/HIToolbox.framework/Headers/HIToolbox.h"
-  llvm::SmallString<1024> HeadersFilename(FrameworkName);
+  SmallString<1024> HeadersFilename(FrameworkName);
   HeadersFilename += "Headers/";
   if (SearchPath != NULL) {
     SearchPath->clear();
@@ -576,6 +656,28 @@ LookupSubframeworkHeader(StringRef Filename,
   return FE;
 }
 
+/// \brief Helper static function to normalize a path for injection into
+/// a synthetic header.
+/*static*/ std::string
+HeaderSearch::NormalizeDashIncludePath(StringRef File, FileManager &FileMgr) {
+  // Implicit include paths should be resolved relative to the current
+  // working directory first, and then use the regular header search
+  // mechanism. The proper way to handle this is to have the
+  // predefines buffer located at the current working directory, but
+  // it has no file entry. For now, workaround this by using an
+  // absolute path if we find the file here, and otherwise letting
+  // header search handle it.
+  SmallString<128> Path(File);
+  llvm::sys::fs::make_absolute(Path);
+  bool exists;
+  if (llvm::sys::fs::exists(Path.str(), exists) || !exists)
+    Path = File;
+  else if (exists)
+    FileMgr.getFile(File);
+
+  return Lexer::Stringify(Path.str());
+}
+
 //===----------------------------------------------------------------------===//
 // File Info Management.
 //===----------------------------------------------------------------------===//
@@ -687,3 +789,247 @@ size_t HeaderSearch::getTotalMemory() const {
 StringRef HeaderSearch::getUniqueFrameworkName(StringRef Framework) {
   return FrameworkNames.GetOrCreateValue(Framework).getKey();
 }
+
+bool HeaderSearch::hasModuleMap(StringRef FileName, 
+                                const DirectoryEntry *Root) {
+  llvm::SmallVector<const DirectoryEntry *, 2> FixUpDirectories;
+  
+  StringRef DirName = FileName;
+  do {
+    // Get the parent directory name.
+    DirName = llvm::sys::path::parent_path(DirName);
+    if (DirName.empty())
+      return false;
+    
+    // Determine whether this directory exists.
+    const DirectoryEntry *Dir = FileMgr.getDirectory(DirName);
+    if (!Dir)
+      return false;
+    
+    // Try to load the module map file in this directory.
+    switch (loadModuleMapFile(Dir)) {
+    case LMM_NewlyLoaded:
+    case LMM_AlreadyLoaded:
+      // Success. All of the directories we stepped through inherit this module
+      // map file.
+      for (unsigned I = 0, N = FixUpDirectories.size(); I != N; ++I)
+        DirectoryHasModuleMap[FixUpDirectories[I]] = true;
+      
+      return true;
+
+    case LMM_NoDirectory:
+    case LMM_InvalidModuleMap:
+      break;
+    }
+
+    // If we hit the top of our search, we're done.
+    if (Dir == Root)
+      return false;
+        
+    // Keep track of all of the directories we checked, so we can mark them as
+    // having module maps if we eventually do find a module map.
+    FixUpDirectories.push_back(Dir);
+  } while (true);
+}
+
+Module *HeaderSearch::findModuleForHeader(const FileEntry *File) {
+  if (Module *Mod = ModMap.findModuleForHeader(File))
+    return Mod;
+  
+  return 0;
+}
+
+bool HeaderSearch::loadModuleMapFile(const FileEntry *File) {
+  const DirectoryEntry *Dir = File->getDir();
+  
+  llvm::DenseMap<const DirectoryEntry *, bool>::iterator KnownDir
+    = DirectoryHasModuleMap.find(Dir);
+  if (KnownDir != DirectoryHasModuleMap.end())
+    return !KnownDir->second;
+  
+  bool Result = ModMap.parseModuleMapFile(File);
+  if (!Result && llvm::sys::path::filename(File->getName()) == "module.map") {
+    // If the file we loaded was a module.map, look for the corresponding
+    // module_private.map.
+    SmallString<128> PrivateFilename(Dir->getName());
+    llvm::sys::path::append(PrivateFilename, "module_private.map");
+    if (const FileEntry *PrivateFile = FileMgr.getFile(PrivateFilename))
+      Result = ModMap.parseModuleMapFile(PrivateFile);
+  }
+  
+  DirectoryHasModuleMap[Dir] = !Result;  
+  return Result;
+}
+
+Module *HeaderSearch::loadFrameworkModule(StringRef Name, 
+                                          const DirectoryEntry *Dir,
+                                          bool IsSystem) {
+  if (Module *Module = ModMap.findModule(Name))
+    return Module;
+  
+  // Try to load a module map file.
+  switch (loadModuleMapFile(Dir)) {
+  case LMM_InvalidModuleMap:
+    break;
+    
+  case LMM_AlreadyLoaded:
+  case LMM_NoDirectory:
+    return 0;
+    
+  case LMM_NewlyLoaded:
+    return ModMap.findModule(Name);
+  }
+
+  // The top-level framework directory, from which we'll infer a framework
+  // module.
+  const DirectoryEntry *TopFrameworkDir = Dir;
+  
+  // The path from the module we're actually looking for back to the top-level
+  // framework name.
+  llvm::SmallVector<StringRef, 2> SubmodulePath;
+  SubmodulePath.push_back(Name);
+  
+  // Walk the directory structure to find any enclosing frameworks.
+  StringRef DirName = Dir->getName();
+  do {
+    // Get the parent directory name.
+    DirName = llvm::sys::path::parent_path(DirName);
+    if (DirName.empty())
+      break;
+    
+    // Determine whether this directory exists.
+    Dir = FileMgr.getDirectory(DirName);
+    if (!Dir)
+      break;
+    
+    // If this is a framework directory, then we're a subframework of this
+    // framework.
+    if (llvm::sys::path::extension(DirName) == ".framework") {
+      SubmodulePath.push_back(llvm::sys::path::stem(DirName));
+      TopFrameworkDir = Dir;
+    }
+  } while (true);
+  
+  // Try to infer a module map from the top-level framework directory.
+  Module *Result = ModMap.inferFrameworkModule(SubmodulePath.back(), 
+                                               TopFrameworkDir,
+                                               IsSystem,
+                                               /*Parent=*/0);
+  
+  // Follow the submodule path to find the requested (sub)framework module
+  // within the top-level framework module.
+  SubmodulePath.pop_back();
+  while (!SubmodulePath.empty() && Result) {
+    Result = ModMap.lookupModuleQualified(SubmodulePath.back(), Result);
+    SubmodulePath.pop_back();
+  }
+  return Result;
+}
+
+
+HeaderSearch::LoadModuleMapResult 
+HeaderSearch::loadModuleMapFile(StringRef DirName) {
+  if (const DirectoryEntry *Dir = FileMgr.getDirectory(DirName))
+    return loadModuleMapFile(Dir);
+  
+  return LMM_NoDirectory;
+}
+
+HeaderSearch::LoadModuleMapResult 
+HeaderSearch::loadModuleMapFile(const DirectoryEntry *Dir) {
+  llvm::DenseMap<const DirectoryEntry *, bool>::iterator KnownDir
+    = DirectoryHasModuleMap.find(Dir);
+  if (KnownDir != DirectoryHasModuleMap.end())
+    return KnownDir->second? LMM_AlreadyLoaded : LMM_InvalidModuleMap;
+  
+  SmallString<128> ModuleMapFileName;
+  ModuleMapFileName += Dir->getName();
+  unsigned ModuleMapDirNameLen = ModuleMapFileName.size();
+  llvm::sys::path::append(ModuleMapFileName, "module.map");
+  if (const FileEntry *ModuleMapFile = FileMgr.getFile(ModuleMapFileName)) {
+    // We have found a module map file. Try to parse it.
+    if (ModMap.parseModuleMapFile(ModuleMapFile)) {
+      // No suitable module map.
+      DirectoryHasModuleMap[Dir] = false;
+      return LMM_InvalidModuleMap;
+    }
+
+    // This directory has a module map.
+    DirectoryHasModuleMap[Dir] = true;
+    
+    // Check whether there is a private module map that we need to load as well.
+    ModuleMapFileName.erase(ModuleMapFileName.begin() + ModuleMapDirNameLen,
+                            ModuleMapFileName.end());
+    llvm::sys::path::append(ModuleMapFileName, "module_private.map");
+    if (const FileEntry *PrivateModuleMapFile
+                                        = FileMgr.getFile(ModuleMapFileName)) {
+      if (ModMap.parseModuleMapFile(PrivateModuleMapFile)) {
+        // No suitable module map.
+        DirectoryHasModuleMap[Dir] = false;
+        return LMM_InvalidModuleMap;
+      }      
+    }
+    
+    return LMM_NewlyLoaded;
+  }
+  
+  // No suitable module map.
+  DirectoryHasModuleMap[Dir] = false;
+  return LMM_InvalidModuleMap;
+}
+
+void HeaderSearch::collectAllModules(llvm::SmallVectorImpl<Module *> &Modules) {
+  Modules.clear();
+  
+  // Load module maps for each of the header search directories.
+  for (unsigned Idx = 0, N = SearchDirs.size(); Idx != N; ++Idx) {
+    if (SearchDirs[Idx].isFramework()) {
+      llvm::error_code EC;
+      SmallString<128> DirNative;
+      llvm::sys::path::native(SearchDirs[Idx].getFrameworkDir()->getName(),
+                              DirNative);
+      
+      // Search each of the ".framework" directories to load them as modules.
+      bool IsSystem = SearchDirs[Idx].getDirCharacteristic() != SrcMgr::C_User;
+      for (llvm::sys::fs::directory_iterator Dir(DirNative.str(), EC), DirEnd;
+           Dir != DirEnd && !EC; Dir.increment(EC)) {
+        if (llvm::sys::path::extension(Dir->path()) != ".framework")
+          continue;
+        
+        const DirectoryEntry *FrameworkDir = FileMgr.getDirectory(Dir->path());
+        if (!FrameworkDir)
+          continue;
+        
+        // Load this framework module.
+        loadFrameworkModule(llvm::sys::path::stem(Dir->path()), FrameworkDir,
+                            IsSystem);
+      }
+      continue;
+    }
+    
+    // FIXME: Deal with header maps.
+    if (SearchDirs[Idx].isHeaderMap())
+      continue;
+    
+    // Try to load a module map file for the search directory.
+    loadModuleMapFile(SearchDirs[Idx].getDir());
+    
+    // Try to load module map files for immediate subdirectories of this search
+    // directory.
+    llvm::error_code EC;
+    SmallString<128> DirNative;
+    llvm::sys::path::native(SearchDirs[Idx].getDir()->getName(), DirNative);
+    for (llvm::sys::fs::directory_iterator Dir(DirNative.str(), EC), DirEnd;
+         Dir != DirEnd && !EC; Dir.increment(EC)) {
+      loadModuleMapFile(Dir->path());
+    }
+  }
+  
+  // Populate the list of modules.
+  for (ModuleMap::module_iterator M = ModMap.module_begin(), 
+                               MEnd = ModMap.module_end();
+       M != MEnd; ++M) {
+    Modules.push_back(M->getValue());
+  }
+}
+