Put the mechanism in place to track modifications in an AST entity that were committed after

its initial creation/deserialization and store the changes in a chained PCH.

The idea is that the AST entities call methods on the ASTMutationListener to give notifications
of changes; the PCHWriter implements the ASTMutationListener interface and stores the incremental changes
of the updated entity. WIP

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@117235 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 1 deletions

diff --git a/lib/Serialization/GeneratePCH.cpp b/lib/Serialization/GeneratePCH.cpp
index 5329b6cbd4..0d8ec736b6 100644
--- a/lib/Serialization/GeneratePCH.cpp
+++ b/lib/Serialization/GeneratePCH.cpp
@@ -30,7 +30,7 @@ PCHGenerator::PCHGenerator(const Preprocessor &PP,
                            const char *isysroot,
                            llvm::raw_ostream *OS)
   : PP(PP), isysroot(isysroot), Out(OS), SemaPtr(0),
-    StatCalls(0), Stream(Buffer), Writer(Stream) {
+    StatCalls(0), Stream(Buffer), Writer(Stream), Chaining(Chaining) {
 
   // Install a stat() listener to keep track of all of the stat()
   // calls.
@@ -59,6 +59,12 @@ void PCHGenerator::HandleTranslationUnit(ASTContext &Ctx) {
   Buffer.clear();
 }
 
+ASTMutationListener *PCHGenerator::GetASTMutationListener() {
+  if (Chaining)
+    return &Writer;
+  return 0;
+}
+
 ASTDeserializationListener *PCHGenerator::GetASTDeserializationListener() {
   return &Writer;
 }