update comments, no functionality change

[oota-llvm.git] / include / llvm / GlobalValue.h

diff --git a/include/llvm/GlobalValue.h b/include/llvm/GlobalValue.h
index 72a45f4bc7664c3a0a3124d618003d3865f29034..d2d91303707176a9c8048a47420ee13a2a614dd5 100644 (file)
--- a/include/llvm/GlobalValue.h
+++ b/include/llvm/GlobalValue.h
@@ -8,9 +8,10 @@
 //===----------------------------------------------------------------------===//
 //
 // This file is a common base class of all globally definable objects.  As such,
-// it is subclassed by GlobalVariable and by Function.  This is used because you
-// can do certain things with these global objects that you can't do to anything
-// else.  For example, use the address of one as a constant.
+// it is subclassed by GlobalVariable, GlobalAlias and by Function.  This is
+// used because you can do certain things with these global objects that you
+// can't do to anything else.  For example, use the address of one as a
+// constant.
 //
 //===----------------------------------------------------------------------===//
 
@@ -29,7 +30,7 @@ class GlobalValue : public Constant {
 public:
   /// @brief An enumeration for the kinds of linkage for global values.
   enum LinkageTypes {
-    ExternalLinkage,    ///< Externally visible function
+    ExternalLinkage = 0,///< Externally visible function
     LinkOnceLinkage,    ///< Keep one copy of function when linking (inline)
     WeakLinkage,        ///< Keep one copy of named function when linking (weak)
     AppendingLinkage,   ///< Special purpose, only applies to global arrays
@@ -42,8 +43,9 @@ public:
 
   /// @brief An enumeration for the kinds of visibility of global values.
   enum VisibilityTypes {
-    DefaultVisibility,  ///< The GV is visible
-    HiddenVisibility    ///< The GV is hidden
+    DefaultVisibility = 0,  ///< The GV is visible
+    HiddenVisibility,       ///< The GV is hidden
+    ProtectedVisibility     ///< The GV is protected
   };
 
 protected:
@@ -55,10 +57,12 @@ protected:
   }
 
   Module *Parent;
-  LinkageTypes Linkage;   // The linkage of this global
-  VisibilityTypes Visibility;  // The visibility style of this global
-  unsigned Alignment;     // Alignment of this symbol, must be power of two
-  std::string Section;    // Section to emit this into, empty mean default
+  // Note: VC++ treats enums as signed, so an extra bit is required to prevent
+  // Linkage and Visibility from turning into negative values.
+  LinkageTypes Linkage : 5;   // The linkage of this global
+  unsigned Visibility : 2;    // The visibility style of this global
+  unsigned Alignment : 16;    // Alignment of this symbol, must be power of two
+  std::string Section;        // Section to emit this into, empty mean default
 public:
   ~GlobalValue() {
     removeDeadConstantUsers();   // remove any dead constants using this.
@@ -70,8 +74,11 @@ public:
     Alignment = Align;
   }
 
-  VisibilityTypes getVisibility() const { return Visibility; }
+  VisibilityTypes getVisibility() const { return (VisibilityTypes)Visibility; }
   bool hasHiddenVisibility() const { return Visibility == HiddenVisibility; }
+  bool hasProtectedVisibility() const {
+    return Visibility == ProtectedVisibility;
+  }
   void setVisibility(VisibilityTypes V) { Visibility = V; }
   
   bool hasSection() const { return !Section.empty(); }
@@ -134,7 +141,8 @@ public:
   static inline bool classof(const GlobalValue *) { return true; }
   static inline bool classof(const Value *V) {
     return V->getValueID() == Value::FunctionVal ||
-           V->getValueID() == Value::GlobalVariableVal;
+           V->getValueID() == Value::GlobalVariableVal ||
+           V->getValueID() == Value::GlobalAliasVal;
   }
 };