[Modules] Add merged Files to UsedModuleFiles

This is needed by no casacading chanegs feature. A BMI of a module
interface needs to merge the hash value of all the module files that
the users can touched actually.

1 files changed, 6 insertions, 1 deletions

diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
index 04cbd1ca..06cd6c7 100644
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -4062,6 +4062,10 @@ void ASTWriter::handleVTable(CXXRecordDecl *RD) {
   PendingEmittingVTables.push_back(RD);
 }
 
+void ASTWriter::addTouchedModuleFile(serialization::ModuleFile *MF) {
+  TouchedModuleFiles.insert(MF);
+}
+
 //===----------------------------------------------------------------------===//
 // DeclContext's Name Lookup Table Serialization
 //===----------------------------------------------------------------------===//
@@ -4106,7 +4110,7 @@ public:
            "have reference to loaded module file but no chain?");
 
     using namespace llvm::support;
-
+    Writer.addTouchedModuleFile(F);
     endian::write<uint32_t>(Out, Writer.getChain()->getModuleFileID(F),
                             llvm::endianness::little);
   }
@@ -4473,6 +4477,7 @@ public:
            "have reference to loaded module file but no chain?");
 
     using namespace llvm::support;
+    Writer.addTouchedModuleFile(F);
     endian::write<uint32_t>(Out, Writer.getChain()->getModuleFileID(F),
                             llvm::endianness::little);
   }