Overhaul of Stmt allocation:

- Made allocation of Stmt objects using vanilla new/delete a *compiler
  error* by making this new/delete "protected" within class Stmt.
- Now the only way to allocate Stmt objects is by using the new
  operator that takes ASTContext& as an argument.  This ensures that
  all Stmt nodes are allocated from the same (pool) allocator.
- Naturally, these two changes required that *all* creation sites for
  AST nodes use new (ASTContext&).  This is a large patch, but the
  majority of the changes are just this mechanical adjustment.
- The above changes also mean that AST nodes can no longer be
  deallocated using 'delete'.  Instead, one most do
  StmtObject->Destroy(ASTContext&) or do
  ASTContextObject.Deallocate(StmtObject) (the latter not running the
  'Destroy' method).

Along the way I also...
- Made CompoundStmt allocate its array of Stmt* using the allocator in
  ASTContext (previously it used std::vector).  There are a whole
  bunch of other Stmt classes that need to be similarly changed to
  ensure that all memory allocated for ASTs comes from the allocator
  in ASTContext.
- Added a new smart pointer ExprOwningPtr to Sema.h.  This replaces
  the uses of llvm::OwningPtr within Sema, as llvm::OwningPtr used
  'delete' to free memory instead of a Stmt's 'Destroy' method.

Big thanks to Doug Gregor for helping with the acrobatics of making
'new/delete' private and the new smart pointer ExprOwningPtr!


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@63997 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 18 insertions, 3 deletions

diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index 4878403333..88d7a0f6f4 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -1970,7 +1970,7 @@ struct BlockSemaInfo {
   
   BlockDecl *TheDecl;
   
-  /// TheScope - This is the scope for the block itself, which contains
+  /// TheScope - This is the scope for the block itself, which containsfile://localhost/Volumes/Data/Users/kremenek/llvm/tools/clang
   /// arguments etc.
   Scope *TheScope;
   
@@ -1982,8 +1982,23 @@ struct BlockSemaInfo {
   /// to the outer block.
   BlockSemaInfo *PrevBlockInfo;
 };
-
-
+  
+//===--------------------------------------------------------------------===//
+// Typed version of Parser::ExprArg (smart pointer for wrapping Expr pointers).
+template <typename T>
+class ExprOwningPtr : public Action::ExprArg {
+public:
+  ExprOwningPtr(Sema *S, T *expr) : Action::ExprArg(*S, expr) {};
+  
+  void reset(T* p) { Action::ExprArg::operator=(p); }
+  T* get() const { return static_cast<T*>(Action::ExprArg::get()); }
+  T* take() { return static_cast<T*>(Action::ExprArg::take()); }
+  T* release() { return take(); }
+  
+  T& operator*() const { return *get(); }
+  T* operator->() const { return get(); }
+};
+  
 }  // end namespace clang
 
 #endif