Put the invalid flag of OwningResult into the Action pointer.

This shrinks OwningResult by one pointer. Since it is no longer larger than OwningPtr, merge the two.
This leads to simpler client code and speeds up my benchmark by 2.7%.
For some reason, this exposes a previously hidden bug, causing a regression in SemaCXX/condition.cpp.

llvm-svn: 63867

2 files changed, 59 insertions, 136 deletions

diff --git a/clang/include/clang/Parse/Action.h b/clang/include/clang/Parse/Action.h
index 28e63b353aa..271a3a8297a 100644
--- a/clang/include/clang/Parse/Action.h
+++ b/clang/include/clang/Parse/Action.h
@@ -94,9 +94,15 @@ public:
   // is complete.
 
   /// Single expressions or statements as arguments.
+#if !defined(DISABLE_SMART_POINTERS)
+  typedef ASTOwningResult<&ActionBase::DeleteExpr> ExprArg;
+  typedef ASTOwningResult<&ActionBase::DeleteStmt> StmtArg;
+  typedef ASTOwningResult<&ActionBase::DeleteTemplateArg> TemplateArgArg;
+#else
   typedef ASTOwningPtr<&ActionBase::DeleteExpr> ExprArg;
   typedef ASTOwningPtr<&ActionBase::DeleteStmt> StmtArg;
   typedef ASTOwningPtr<&ActionBase::DeleteTemplateArg> TemplateArgArg;
+#endif
 
   /// Multiple expressions or statements as arguments.
   typedef ASTMultiPtr<&ActionBase::DeleteExpr> MultiExprArg;
@@ -602,7 +608,7 @@ public:
 
   virtual OwningExprResult ActOnParenExpr(SourceLocation L, SourceLocation R,
                                           ExprArg Val) {
-    return move_res(Val);  // Default impl returns operand.
+    return move(Val);  // Default impl returns operand.
   }
 
   // Postfix Expressions.
diff --git a/clang/include/clang/Parse/Ownership.h b/clang/include/clang/Parse/Ownership.h
index 704d6b5f1e9..6017db761f9 100644
--- a/clang/include/clang/Parse/Ownership.h
+++ b/clang/include/clang/Parse/Ownership.h
@@ -105,6 +105,8 @@
 // Flip this switch to measure performance impact of the smart pointers.
 //#define DISABLE_SMART_POINTERS
 
+#include "llvm/ADT/PointerIntPair.h"
+
 namespace clang
 {
   // Basic
@@ -228,9 +230,6 @@ namespace clang
   /// has an extra flag to indicate an additional success status.
   template <ASTDestroyer Destroyer> class ASTOwningResult;
 
-  /// ASTOwningPtr - A moveable smart pointer for AST nodes.
-  template <ASTDestroyer Destroyer> class ASTOwningPtr;
-
   /// ASTMultiPtr - A moveable smart pointer to multiple AST nodes. Only owns
   /// the individual pointers, not the array holding them.
   template <ASTDestroyer Destroyer> class ASTMultiPtr;
@@ -250,19 +249,6 @@ namespace clang
       ASTOwningResult<Destroyer> * operator ->() { return &Moved; }
     };
 
-    /// Move emulation helper for ASTOwningPtr. NEVER EVER use this class
-    /// directly if you don't know what you're doing.
-    template <ASTDestroyer Destroyer>
-    class ASTPtrMover
-    {
-      ASTOwningPtr<Destroyer> &Moved;
-
-    public:
-      ASTPtrMover(ASTOwningPtr<Destroyer> &moved) : Moved(moved) {}
-
-      ASTOwningPtr<Destroyer> * operator ->() { return &Moved; }
-    };
-
     /// Move emulation helper for ASTMultiPtr. NEVER EVER use this class
     /// directly if you don't know what you're doing.
     template <ASTDestroyer Destroyer>
@@ -279,91 +265,40 @@ namespace clang
       void release();
     };
   }
-#endif
+#else
 
+  /// Kept only as a type-safe wrapper for a void pointer, when smart pointers
+  /// are disabled. When they are enabled, ASTOwningResult takes over.
   template <ASTDestroyer Destroyer>
   class ASTOwningPtr
   {
-#if !defined(DISABLE_SMART_POINTERS)
-    ActionBase *Actions;
-#endif
     void *Node;
 
-#if !defined(DISABLE_SMART_POINTERS)
-    friend class moving::ASTPtrMover<Destroyer>;
-
-    ASTOwningPtr(ASTOwningPtr&); // DO NOT IMPLEMENT
-    ASTOwningPtr& operator =(ASTOwningPtr&); // DO NOT IMPLEMENT
-
-    void destroy() {
-      if (Node) {
-        assert(Actions && "Owning pointer without Action owns node.");
-        (Actions->*Destroyer)(Node);
-      }
-    }
-#endif
-
   public:
-#if !defined(DISABLE_SMART_POINTERS)
-    explicit ASTOwningPtr(ActionBase &actions)
-      : Actions(&actions), Node(0) {}
-    ASTOwningPtr(ActionBase &actions, void *node)
-      : Actions(&actions), Node(node) {}
-    /// Move from another owning pointer
-    ASTOwningPtr(moving::ASTPtrMover<Destroyer> mover)
-      : Actions(mover->Actions), Node(mover->take()) {}
-
-    /// Move assignment from another owning pointer
-    ASTOwningPtr & operator =(moving::ASTPtrMover<Destroyer> mover) {
-      Actions = mover->Actions;
-      Node = mover->take();
-      return *this;
-    }
-
-    /// Assignment from a raw pointer. Takes ownership - beware!
-    ASTOwningPtr & operator =(void *raw) {
-      assert((Actions || !raw) && "Cannot assign non-null raw without Action");
-      Node = raw;
-      return *this;
-    }
-#else // Different set if smart pointers are disabled
     explicit ASTOwningPtr(ActionBase &) : Node(0) {}
     ASTOwningPtr(ActionBase &, void *node) : Node(node) {}
     // Normal copying operators are defined implicitly.
-    explicit ASTOwningPtr(void *ptr) : Node(ptr) {}
+    ASTOwningPtr(const ASTOwningResult<Destroyer> &o);
 
     ASTOwningPtr & operator =(void *raw) {
       Node = raw;
       return *this;
     }
-#endif
 
     /// Access to the raw pointer.
     void * get() const { return Node; }
 
     /// Release the raw pointer.
     void * take() {
-#if !defined(DISABLE_SMART_POINTERS)
-      void *tmp = Node;
-      Node = 0;
-      return tmp;
-#else
       return Node;
-#endif
     }
 
     /// Alias for interface familiarity with unique_ptr.
     void * release() {
       return take();
     }
-
-#if !defined(DISABLE_SMART_POINTERS)
-    /// Move hook
-    operator moving::ASTPtrMover<Destroyer>() {
-      return moving::ASTPtrMover<Destroyer>(*this);
-    }
-#endif
   };
+#endif
 
   // Important: There are two different implementations of
   // ASTOwningResult below, depending on whether
@@ -374,74 +309,84 @@ namespace clang
   template <ASTDestroyer Destroyer>
   class ASTOwningResult
   {
-    ASTOwningPtr<Destroyer> Ptr;
-    bool Invalid;
+    llvm::PointerIntPair<ActionBase*, 1, bool> ActionInv;
+    void *Ptr;
 
     friend class moving::ASTResultMover<Destroyer>;
 
     ASTOwningResult(ASTOwningResult&); // DO NOT IMPLEMENT
     ASTOwningResult& operator =(ASTOwningResult&); // DO NOT IMPLEMENT
 
+    void destroy() {
+      if (Ptr) {
+        assert(ActionInv.getPointer() &&
+               "Smart pointer has node but no action.");
+        (ActionInv.getPointer()->*Destroyer)(Ptr);
+        Ptr = 0;
+      }
+    }
+
   public:
     typedef ActionBase::ActionResult<DestroyerToUID<Destroyer>::UID> DumbResult;
 
     explicit ASTOwningResult(ActionBase &actions, bool invalid = false)
-      : Ptr(actions, 0), Invalid(invalid) {}
+      : ActionInv(&actions, invalid), Ptr(0) {}
     ASTOwningResult(ActionBase &actions, void *node)
-      : Ptr(actions, node), Invalid(false) {}
+      : ActionInv(&actions, false), Ptr(node) {}
     ASTOwningResult(ActionBase &actions, const DumbResult &res)
-      : Ptr(actions, res.get()), Invalid(res.isInvalid()) {}
+      : ActionInv(&actions, res.isInvalid()), Ptr(res.get()) {}
     /// Move from another owning result
     ASTOwningResult(moving::ASTResultMover<Destroyer> mover)
-      : Ptr(moving::ASTPtrMover<Destroyer>(mover->Ptr)),
-        Invalid(mover->Invalid) {}
-    /// Move from an owning pointer
-    ASTOwningResult(moving::ASTPtrMover<Destroyer> mover)
-      : Ptr(mover), Invalid(false) {}
+      : ActionInv(mover->ActionInv),
+        Ptr(mover->Ptr) {
+      mover->Ptr = 0;
+    }
 
-    /// Move assignment from another owning result
-    ASTOwningResult & operator =(moving::ASTResultMover<Destroyer> mover) {
-      Ptr = move(mover->Ptr);
-      Invalid = mover->Invalid;
-      return *this;
+    ~ASTOwningResult() {
+      destroy();
     }
 
-    /// Move assignment from an owning ptr
-    ASTOwningResult & operator =(moving::ASTPtrMover<Destroyer> mover) {
-      Ptr = mover;
-      Invalid = false;
+    /// Move assignment from another owning result
+    ASTOwningResult & operator =(moving::ASTResultMover<Destroyer> mover) {
+      destroy();
+      ActionInv = mover->ActionInv;
+      Ptr = mover->Ptr;
+      mover->Ptr = 0;
       return *this;
     }
 
     /// Assignment from a raw pointer. Takes ownership - beware!
-    ASTOwningResult & operator =(void *raw)
-    {
+    ASTOwningResult & operator =(void *raw) {
+      destroy();
       Ptr = raw;
-      Invalid = false;
+      ActionInv.setInt(false);
       return *this;
     }
 
     /// Assignment from an ActionResult. Takes ownership - beware!
     ASTOwningResult & operator =(const DumbResult &res) {
+      destroy();
       Ptr = res.get();
-      Invalid = res.isInvalid();
+      ActionInv.setInt(res.isInvalid());
       return *this;
     }
 
     /// Access to the raw pointer.
-    void * get() const { return Ptr.get(); }
+    void * get() const { return Ptr; }
 
-    bool isInvalid() const { return Invalid; }
+    bool isInvalid() const { return ActionInv.getInt(); }
 
     /// Does this point to a usable AST node? To be usable, the node must be
     /// valid and non-null.
-    bool isUsable() const { return !Invalid && get(); }
+    bool isUsable() const { return !isInvalid() && get(); }
 
     /// Take outside ownership of the raw pointer.
     void * take() {
-      if (Invalid)
+      if (isInvalid())
         return 0;
-      return Ptr.take();
+      void *tmp = Ptr;
+      Ptr = 0;
+      return tmp;
     }
 
     /// Alias for interface familiarity with unique_ptr.
@@ -449,20 +394,15 @@ namespace clang
 
     /// Pass ownership to a classical ActionResult.
     DumbResult result() {
-      if (Invalid)
+      if (isInvalid())
         return true;
-      return Ptr.take();
+      return take();
     }
 
     /// Move hook
     operator moving::ASTResultMover<Destroyer>() {
       return moving::ASTResultMover<Destroyer>(*this);
     }
-
-    /// Special function for moving to an OwningPtr.
-    moving::ASTPtrMover<Destroyer> ptr_move() {
-      return moving::ASTPtrMover<Destroyer>(Ptr);
-    }
   };
 #else
   template <ASTDestroyer Destroyer>
@@ -480,8 +420,7 @@ namespace clang
     ASTOwningResult(ActionBase &actions, void *node) : Result(node) { }
     ASTOwningResult(ActionBase &actions, const DumbResult &res) : Result(res) { }
     // Normal copying semantics are defined implicitly.
-    // The fake movers need this:
-    explicit ASTOwningResult(void *ptr) : Result(ptr) { }
+    ASTOwningResult(const ASTOwningPtr<Destroyer> &o) : Result(o.get()) { }
 
     /// Assignment from a raw pointer. Takes ownership - beware!
     ASTOwningResult & operator =(void *raw)
@@ -616,28 +555,16 @@ namespace clang
   }
 
   template <ASTDestroyer Destroyer> inline
-  ASTOwningPtr<Destroyer> move(ASTOwningPtr<Destroyer> &ptr) {
-    return ASTOwningPtr<Destroyer>(moving::ASTPtrMover<Destroyer>(ptr));
-  }
-
-  template <ASTDestroyer Destroyer> inline
   ASTMultiPtr<Destroyer> move(ASTMultiPtr<Destroyer> &ptr) {
     return ASTMultiPtr<Destroyer>(moving::ASTMultiMover<Destroyer>(ptr));
   }
 
-  // These are necessary because of ambiguity problems.
+#else
 
   template <ASTDestroyer Destroyer> inline
-  ASTOwningPtr<Destroyer> move_arg(ASTOwningResult<Destroyer> &ptr) {
-    return ASTOwningPtr<Destroyer>(ptr.ptr_move());
-  }
-
-  template <ASTDestroyer Destroyer> inline
-  ASTOwningResult<Destroyer> move_res(ASTOwningPtr<Destroyer> &ptr) {
-    return ASTOwningResult<Destroyer>(moving::ASTPtrMover<Destroyer>(ptr));
-  }
-
-#else
+  ASTOwningPtr<Destroyer>::ASTOwningPtr(const ASTOwningResult<Destroyer> &o)
+    : Node(o.get())
+  {}
 
   // These versions are hopefully no-ops.
   template <ASTDestroyer Destroyer> inline
@@ -655,16 +582,6 @@ namespace clang
     return ptr;
   }
 
-  template <ASTDestroyer Destroyer> inline
-  ASTOwningPtr<Destroyer> move_arg(ASTOwningResult<Destroyer> &ptr) {
-    return ASTOwningPtr<Destroyer>(ptr.take());
-  }
-
-  template <ASTDestroyer Destroyer> inline
-  ASTOwningResult<Destroyer> move_res(ASTOwningPtr<Destroyer> &ptr) {
-    return ASTOwningResult<Destroyer>(ptr.get());
-  }
-
 #endif
 
 }