[Modules] Don't eagerly load and associate all the module header files.

In a module-enabled Cocoa PCH file, we spend a lot of time stat'ing the headers
in order to associate the FileEntries with their modules and support implicit
module import.

Use a more lazy scheme by enhancing HeaderInfoTable to store extra info about
the module that a header belongs to, and associate it with its module only when
there is a request for loading the header info for a particular file.

Part of rdar://13391765

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176976 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 1 deletions

diff --git a/include/clang/Lex/ModuleMap.h b/include/clang/Lex/ModuleMap.h
index bb53ff21a0..cffa5b7b66 100644
--- a/include/clang/Lex/ModuleMap.h
+++ b/include/clang/Lex/ModuleMap.h
@@ -33,6 +33,7 @@ class FileEntry;
 class FileManager;
 class DiagnosticConsumer;
 class DiagnosticsEngine;
+class HeaderSearch;
 class ModuleMapParser;
   
 class ModuleMap {
@@ -40,6 +41,7 @@ class ModuleMap {
   IntrusiveRefCntPtr<DiagnosticsEngine> Diags;
   const LangOptions &LangOpts;
   const TargetInfo *Target;
+  HeaderSearch &HeaderInfo;
   
   /// \brief The directory used for Clang-supplied, builtin include headers,
   /// such as "stdint.h".
@@ -147,7 +149,8 @@ public:
   ///
   /// \param Target The target for this translation unit.
   ModuleMap(FileManager &FileMgr, const DiagnosticConsumer &DC,
-            const LangOptions &LangOpts, const TargetInfo *Target);
+            const LangOptions &LangOpts, const TargetInfo *Target,
+            HeaderSearch &HeaderInfo);
 
   /// \brief Destroy the module map.
   ///