[clang] baa9b7c - unique_ptrify the ModuleManager's VisitState linked list

[David Blaikie via cfe-commits]

Author: David Blaikie
Date: 2022-01-19T09:57:46-08:00
New Revision: baa9b7c3c83ab6e4dfb15b8d7815a9958d5b5810

URL: https://github.com/llvm/llvm-project/commit/baa9b7c3c83ab6e4dfb15b8d7815a9958d5b5810
DIFF: https://github.com/llvm/llvm-project/commit/baa9b7c3c83ab6e4dfb15b8d7815a9958d5b5810.diff

LOG: unique_ptrify the ModuleManager's VisitState linked list

Added: 
    

Modified: 
    clang/include/clang/Serialization/ModuleManager.h
    clang/lib/Serialization/ModuleManager.cpp

Removed: 
    


################################################################################
diff  --git a/clang/include/clang/Serialization/ModuleManager.h b/clang/include/clang/Serialization/ModuleManager.h
index 7081eedad4b49..4305bae5ee958 100644
--- a/clang/include/clang/Serialization/ModuleManager.h
+++ b/clang/include/clang/Serialization/ModuleManager.h
@@ -105,10 +105,6 @@ class ModuleManager {
       Stack.reserve(N);
     }
 
-    ~VisitState() {
-      delete NextState;
-    }
-
     /// The stack used when marking the imports of a particular module
     /// as not-to-be-visited.
     SmallVector<ModuleFile *, 4> Stack;
@@ -121,14 +117,14 @@ class ModuleManager {
     unsigned NextVisitNumber = 1;
 
     /// The next visit state.
-    VisitState *NextState = nullptr;
+    std::unique_ptr<VisitState> NextState;
   };
 
   /// The first visit() state in the chain.
-  VisitState *FirstVisitState = nullptr;
+  std::unique_ptr<VisitState> FirstVisitState;
 
-  VisitState *allocateVisitState();
-  void returnVisitState(VisitState *State);
+  std::unique_ptr<VisitState> allocateVisitState();
+  void returnVisitState(std::unique_ptr<VisitState> State);
 
 public:
   using ModuleIterator = llvm::pointee_iterator<
@@ -142,7 +138,6 @@ class ModuleManager {
   explicit ModuleManager(FileManager &FileMgr, InMemoryModuleCache &ModuleCache,
                          const PCHContainerReader &PCHContainerRdr,
                          const HeaderSearch &HeaderSearchInfo);
-  ~ModuleManager();
 
   /// Forward iterator to traverse all loaded modules.
   ModuleIterator begin() { return Chain.begin(); }

diff  --git a/clang/lib/Serialization/ModuleManager.cpp b/clang/lib/Serialization/ModuleManager.cpp
index f4882c7be3f7d..4fd217cf7a6ea 100644
--- a/clang/lib/Serialization/ModuleManager.cpp
+++ b/clang/lib/Serialization/ModuleManager.cpp
@@ -304,23 +304,22 @@ ModuleManager::addInMemoryBuffer(StringRef FileName,
   InMemoryBuffers[Entry] = std::move(Buffer);
 }
 
-ModuleManager::VisitState *ModuleManager::allocateVisitState() {
+std::unique_ptr<ModuleManager::VisitState> ModuleManager::allocateVisitState() {
   // Fast path: if we have a cached state, use it.
   if (FirstVisitState) {
-    VisitState *Result = FirstVisitState;
-    FirstVisitState = FirstVisitState->NextState;
-    Result->NextState = nullptr;
+    auto Result = std::move(FirstVisitState);
+    FirstVisitState = std::move(Result->NextState);
     return Result;
   }
 
   // Allocate and return a new state.
-  return new VisitState(size());
+  return std::make_unique<VisitState>(size());
 }
 
-void ModuleManager::returnVisitState(VisitState *State) {
+void ModuleManager::returnVisitState(std::unique_ptr<VisitState> State) {
   assert(State->NextState == nullptr && "Visited state is in list?");
-  State->NextState = FirstVisitState;
-  FirstVisitState = State;
+  State->NextState = std::move(FirstVisitState);
+  FirstVisitState = std::move(State);
 }
 
 void ModuleManager::setGlobalIndex(GlobalModuleIndex *Index) {
@@ -351,8 +350,6 @@ ModuleManager::ModuleManager(FileManager &FileMgr,
     : FileMgr(FileMgr), ModuleCache(&ModuleCache),
       PCHContainerRdr(PCHContainerRdr), HeaderSearchInfo(HeaderSearchInfo) {}
 
-ModuleManager::~ModuleManager() { delete FirstVisitState; }
-
 void ModuleManager::visit(llvm::function_ref<bool(ModuleFile &M)> Visitor,
                           llvm::SmallPtrSetImpl<ModuleFile *> *ModuleFilesHit) {
   // If the visitation order vector is the wrong size, recompute the order.
@@ -396,11 +393,10 @@ void ModuleManager::visit(llvm::function_ref<bool(ModuleFile &M)> Visitor,
 
     assert(VisitOrder.size() == N && "Visitation order is wrong?");
 
-    delete FirstVisitState;
     FirstVisitState = nullptr;
   }
 
-  VisitState *State = allocateVisitState();
+  auto State = allocateVisitState();
   unsigned VisitNumber = State->NextVisitNumber++;
 
   // If the caller has provided us with a hit-set that came from the global
@@ -452,7 +448,7 @@ void ModuleManager::visit(llvm::function_ref<bool(ModuleFile &M)> Visitor,
     } while (true);
   }
 
-  returnVisitState(State);
+  returnVisitState(std::move(State));
 }
 
 bool ModuleManager::lookupModuleFile(StringRef FileName, off_t ExpectedSize,