From bbfd68dd5288c435cfd6aef1264263e5f856958d Mon Sep 17 00:00:00 2001
From: Ted Kremenek <kremenek@apple.com>
Date: Wed, 23 Dec 2009 21:13:52 +0000
Subject: [PATCH] Tidy up ~ASTContext a bit by turning orphan compound
 statements into for loops.  Also do not manually free the Type objects when
 the 'FreeMemory' flag is set, as they will be deallocated when the
 BumpPtrAllocator is destroyed.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@92047 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/AST/ASTContext.cpp | 51 +++++++++++++++++++++---------------------
 1 file changed, 25 insertions(+), 26 deletions(-)

diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index 0e36a0ad1c..bba169938b 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -56,44 +56,43 @@ ASTContext::ASTContext(const LangOptions& LOpts, SourceManager &SM,
 }
 
 ASTContext::~ASTContext() {
-  // Deallocate all the types.
-  while (!Types.empty()) {
-    Types.back()->Destroy(*this);
-    Types.pop_back();
-  }
+  if (FreeMemory) {
+    // Deallocate all the types.
+    while (!Types.empty()) {
+      Types.back()->Destroy(*this);
+      Types.pop_back();
+    }
 
-  {
-    llvm::FoldingSet<ExtQuals>::iterator
-      I = ExtQualNodes.begin(), E = ExtQualNodes.end();
-    while (I != E)
+    for (llvm::FoldingSet<ExtQuals>::iterator
+         I = ExtQualNodes.begin(), E = ExtQualNodes.end(); I != E; ) {
+      // Increment in loop to prevent using deallocated memory.
       Deallocate(&*I++);
-  }
-
-  {
-    llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
-      I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end();
-    while (I != E) {
-      ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second);
-      delete R;
     }
   }
 
-  {
-    llvm::DenseMap<const ObjCContainerDecl*, const ASTRecordLayout*>::iterator
-      I = ObjCLayouts.begin(), E = ObjCLayouts.end();
-    while (I != E) {
-      ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second);
-      delete R;
-    }
+  for (llvm::DenseMap<const RecordDecl*, const ASTRecordLayout*>::iterator
+       I = ASTRecordLayouts.begin(), E = ASTRecordLayouts.end(); I != E; ) {
+    // Increment in loop to prevent using deallocated memory.
+    ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second);
+    delete R;
+  }
+
+  for (llvm::DenseMap<const ObjCContainerDecl*,
+                      const ASTRecordLayout*>::iterator
+       I = ObjCLayouts.begin(), E = ObjCLayouts.end(); I != E; ) {
+    // Increment in loop to prevent using deallocated memory.
+    ASTRecordLayout *R = const_cast<ASTRecordLayout*>((I++)->second);
+    delete R;
   }
 
   // Destroy nested-name-specifiers.
   for (llvm::FoldingSet<NestedNameSpecifier>::iterator
          NNS = NestedNameSpecifiers.begin(),
          NNSEnd = NestedNameSpecifiers.end();
-       NNS != NNSEnd;
-       /* Increment in loop */)
+       NNS != NNSEnd; ) {
+    // Increment in loop to prevent using deallocated memory.
     (*NNS++).Destroy(*this);
+  }
 
   if (GlobalNestedNameSpecifier)
     GlobalNestedNameSpecifier->Destroy(*this);