[modules] Fix HeaderFileInfo serialization to store all the known owning modules for a header, not just the current favourite.

llvm-svn: 245390

1 files changed, 33 insertions, 32 deletions

diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index 6d41d155c56..fc9d29a9080 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -1556,14 +1556,15 @@ HeaderFileInfoTrait::ReadData(internal_key_ref key, const unsigned char *d,
   using namespace llvm::support;
   HeaderFileInfo HFI;
   unsigned Flags = *d++;
-  HFI.HeaderRole = static_cast<ModuleMap::ModuleHeaderRole>
-                   ((Flags >> 6) & 0x03);
-  HFI.isImport = (Flags >> 5) & 0x01;
-  HFI.isPragmaOnce = (Flags >> 4) & 0x01;
-  HFI.DirInfo = (Flags >> 2) & 0x03;
-  HFI.Resolved = (Flags >> 1) & 0x01;
+  // FIXME: Refactor with mergeHeaderFileInfo in HeaderSearch.cpp.
+  HFI.isImport |= (Flags >> 4) & 0x01;
+  HFI.isPragmaOnce |= (Flags >> 3) & 0x01;
+  HFI.DirInfo = (Flags >> 1) & 0x03;
   HFI.IndexHeaderMapHeader = Flags & 0x01;
-  HFI.NumIncludes = endian::readNext<uint16_t, little, unaligned>(d);
+  // FIXME: Find a better way to handle this. Maybe just store a
+  // "has been included" flag?
+  HFI.NumIncludes = std::max(endian::readNext<uint16_t, little, unaligned>(d),
+                             HFI.NumIncludes);
   HFI.ControllingMacroID = Reader.getGlobalIdentifierID(
       M, endian::readNext<uint32_t, little, unaligned>(d));
   if (unsigned FrameworkOffset =
@@ -1573,32 +1574,32 @@ HeaderFileInfoTrait::ReadData(internal_key_ref key, const unsigned char *d,
     StringRef FrameworkName(FrameworkStrings + FrameworkOffset - 1);
     HFI.Framework = HS->getUniqueFrameworkName(FrameworkName);
   }
-  
-  if (d != End) {
+
+  assert((End - d) % 4 == 0 &&
+         "Wrong data length in HeaderFileInfo deserialization");
+  while (d != End) {
     uint32_t LocalSMID = endian::readNext<uint32_t, little, unaligned>(d);
-    if (LocalSMID) {
-      // This header is part of a module. Associate it with the module to enable
-      // implicit module import.
-      SubmoduleID GlobalSMID = Reader.getGlobalSubmoduleID(M, LocalSMID);
-      Module *Mod = Reader.getSubmodule(GlobalSMID);
-      HFI.isModuleHeader = true;
-      FileManager &FileMgr = Reader.getFileManager();
-      ModuleMap &ModMap =
-          Reader.getPreprocessor().getHeaderSearchInfo().getModuleMap();
-      // FIXME: This information should be propagated through the
-      // SUBMODULE_HEADER etc records rather than from here.
-      // FIXME: We don't ever mark excluded headers.
-      std::string Filename = key.Filename;
-      if (key.Imported)
-        Reader.ResolveImportedPath(M, Filename);
-      Module::Header H = { key.Filename, FileMgr.getFile(Filename) };
-      ModMap.addHeader(Mod, H, HFI.getHeaderRole());
-    }
-  }
-
-  assert(End == d && "Wrong data length in HeaderFileInfo deserialization");
-  (void)End;
-        
+    auto HeaderRole = static_cast<ModuleMap::ModuleHeaderRole>(LocalSMID & 3);
+    LocalSMID >>= 2;
+
+    // This header is part of a module. Associate it with the module to enable
+    // implicit module import.
+    SubmoduleID GlobalSMID = Reader.getGlobalSubmoduleID(M, LocalSMID);
+    Module *Mod = Reader.getSubmodule(GlobalSMID);
+    FileManager &FileMgr = Reader.getFileManager();
+    ModuleMap &ModMap =
+        Reader.getPreprocessor().getHeaderSearchInfo().getModuleMap();
+
+    std::string Filename = key.Filename;
+    if (key.Imported)
+      Reader.ResolveImportedPath(M, Filename);
+    // FIXME: This is not always the right filename-as-written, but we're not
+    // going to use this information to rebuild the module, so it doesn't make
+    // a lot of difference.
+    Module::Header H = { key.Filename, FileMgr.getFile(Filename) };
+    ModMap.addHeader(Mod, H, HeaderRole);
+  }
+
   // This HeaderFileInfo was externally loaded.
   HFI.External = true;
   return HFI;