From 97c5bafb2fc658d2a3dab5239fafd294cd300515 Mon Sep 17 00:00:00 2001
From: Axel Naumann <Axel.Naumann@cern.ch>
Date: Sat, 25 Jun 2016 00:14:00 +0200
Subject: [PATCH] Merge transaction unlinking into deregisterTransaction; pass
 nullptr if Transaction gets unloaded.

---
 lib/Interpreter/IncrementalParser.cpp   | 21 ++++++++++++++++-----
 lib/Interpreter/IncrementalParser.h     |  2 +-
 lib/Interpreter/Interpreter.cpp         |  8 +++++---
 lib/Interpreter/TransactionUnloader.cpp |  8 --------
 lib/Interpreter/TransactionUnloader.h   |  1 -
 5 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/lib/Interpreter/IncrementalParser.cpp b/lib/Interpreter/IncrementalParser.cpp
index 9aea2c82..2eab886c 100644
--- a/lib/Interpreter/IncrementalParser.cpp
+++ b/lib/Interpreter/IncrementalParser.cpp
@@ -352,7 +352,7 @@ namespace cling {
     return ParseResultTransaction(T, ParseResult);
   }
 
-  void IncrementalParser::commitTransaction(ParseResultTransaction PRT) {
+  void IncrementalParser::commitTransaction(ParseResultTransaction& PRT) {
     Transaction* T = PRT.getPointer();
     if (!T) {
       if (PRT.getInt() != kSuccess) {
@@ -392,6 +392,8 @@ namespace cling {
       Diags.Reset(/*soft=*/true);
       Diags.getClient()->clear();
 
+      PRT.setPointer(nullptr);
+      PRT.setInt(kFailed);
       m_Interpreter->unload(*T);
 
       if (MustStartNewModule) {
@@ -418,8 +420,10 @@ namespace cling {
 
       for (Transaction::const_nested_iterator I = T->nested_begin(),
             E = T->nested_end(); I != E; ++I)
-        if ((*I)->getState() != Transaction::kCommitted)
-          commitTransaction(ParseResultTransaction(*I, PR));
+        if ((*I)->getState() != Transaction::kCommitted) {
+          ParseResultTransaction PRT(*I, PR);
+          commitTransaction(PRT);
+        }
     }
 
     // If there was an error coming from the transformers.
@@ -515,6 +519,7 @@ namespace cling {
     // trigger emission of weak symbols by providing use.
     ParseResultTransaction PRT = endTransaction(deserT);
     commitTransaction(PRT);
+    deserT = PRT.getPointer();
 
     // This llvm::Module is done; finalize it and pass it to the execution
     // engine.
@@ -537,7 +542,9 @@ namespace cling {
       // Reset the module builder to clean up global initializers, c'tors, d'tors
       getCodeGenerator()->HandleTranslationUnit(Context);
       FileName = OldName;
-      commitTransaction(endTransaction(deserT));
+      auto PRT = endTransaction(deserT);
+      commitTransaction(PRT);
+      deserT = PRT.getPointer();
 
       std::unique_ptr<llvm::Module> M(getCodeGenerator()->ReleaseModule());
 
@@ -576,13 +583,17 @@ namespace cling {
   }
 
   void IncrementalParser::deregisterTransaction(Transaction& T) {
-    if (!T.getParent()) {
+    if (Transaction* Parent = T.getParent()) {
+      Parent->removeNestedTransaction(&T);
+      T.setParent(0);
+    } else {
       // Remove from the queue
       assert(&T == m_Transactions.back() && "Out of order transaction removal");
       m_Transactions.pop_back();
       if (!m_Transactions.empty())
         m_Transactions.back()->setNext(0);
     }
+
     m_TransactionPool->releaseTransaction(&T);
   }
 
diff --git a/lib/Interpreter/IncrementalParser.h b/lib/Interpreter/IncrementalParser.h
index d597b764..52c3a626 100644
--- a/lib/Interpreter/IncrementalParser.h
+++ b/lib/Interpreter/IncrementalParser.h
@@ -130,7 +130,7 @@ namespace cling {
     ///\param[in] PRT - the transaction (ParseResultTransaction, really) to be
     /// committed
     ///
-    void commitTransaction(ParseResultTransaction PRT);
+    void commitTransaction(ParseResultTransaction& PRT);
 
     ///\brief Runs the consumers (e.g. CodeGen) on a non-parsed transaction.
     ///
diff --git a/lib/Interpreter/Interpreter.cpp b/lib/Interpreter/Interpreter.cpp
index 0a0e0b75..eac68de3 100644
--- a/lib/Interpreter/Interpreter.cpp
+++ b/lib/Interpreter/Interpreter.cpp
@@ -693,10 +693,12 @@ namespace cling {
     m_IncrParser->addTransaction(T);
     m_IncrParser->markWholeTransactionAsUsed(T);
     T->setState(Transaction::kCollecting);
-    m_IncrParser->commitTransaction(m_IncrParser->endTransaction(T));
+    auto PRT = m_IncrParser->endTransaction(T);
+    m_IncrParser->commitTransaction(PRT);
 
-    if (executeTransaction(*T))
-      return Interpreter::kSuccess;
+    if ((T = PRT.getPointer()))
+      if (executeTransaction(*T))
+        return Interpreter::kSuccess;
 
     return Interpreter::kFailure;
   }
diff --git a/lib/Interpreter/TransactionUnloader.cpp b/lib/Interpreter/TransactionUnloader.cpp
index 401e836b..4f0cf62f 100644
--- a/lib/Interpreter/TransactionUnloader.cpp
+++ b/lib/Interpreter/TransactionUnloader.cpp
@@ -1228,13 +1228,6 @@ namespace cling {
   }
 
 
-  void TransactionUnloader::unlinkTransactionFromParent(Transaction* T) {
-    if (Transaction* Parent = T->getParent()) {
-      Parent->removeNestedTransaction(T);
-      T->setParent(0);
-    }
-  }
-
   bool TransactionUnloader::unloadDeclarations(Transaction* T,
                                                clang::DeclUnloader& DeclU) {
     bool Successful = true;
@@ -1311,7 +1304,6 @@ namespace cling {
   bool TransactionUnloader::RevertTransaction(Transaction* T) {
     clang::DeclUnloader DeclU(m_Sema, m_CodeGen, T);
 
-    unlinkTransactionFromParent(T);
     bool Successful = unloadDeclarations(T, DeclU);
     Successful = unloadFromPreprocessor(T, DeclU) && Successful;
     Successful = unloadDeserializedDeclarations(T, DeclU) && Successful;
diff --git a/lib/Interpreter/TransactionUnloader.h b/lib/Interpreter/TransactionUnloader.h
index df3e959d..903e03e0 100644
--- a/lib/Interpreter/TransactionUnloader.h
+++ b/lib/Interpreter/TransactionUnloader.h
@@ -31,7 +31,6 @@ namespace cling {
     clang::CodeGenerator* m_CodeGen;
     cling::IncrementalExecutor* m_Exe;
 
-    void unlinkTransactionFromParent(Transaction* T);
     bool unloadDeclarations(Transaction* T, clang::DeclUnloader& DeclU);
     bool unloadDeserializedDeclarations(Transaction* T,
                                         clang::DeclUnloader& DeclU);