Add some more matcher classes for shifts.

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

diff --git a/include/llvm/Constant.h b/include/llvm/Constant.h
index fc63b35b20327d86156e7a2b44cb5841404d26f4..603afcbff9f879284892eb5736317bca34de91a3 100644 (file)
--- a/include/llvm/Constant.h
+++ b/include/llvm/Constant.h
@@ -18,7 +18,26 @@
 
 namespace llvm {
 
+/// This is an important base class in LLVM. It provides the common facilities
+/// of all constant values in an LLVM program. A constant is a value that is
+/// immutable at runtime. Functions are constants because their address is
+/// immutable. Same with global variables. 
+/// 
+/// All constants share the capabilities provided in this class. All constants
+/// can have a null value. They can have an operand list. Constants can be
+/// simple (integer and floating point values), complex (arrays and structures),
+/// or expression based (computations yielding a constant value composed of 
+/// only certain operators and other constant values).
+/// 
+/// Note that Constants are immutable (once created they never change) 
+/// and are fully shared by structural equivalence.  This means that two 
+/// structurally equivalent constants will always have the same address.  
+/// Constant's are created on demand as needed and never deleted: thus clients 
+/// don't have to worry about the lifetime of the objects.
+/// @brief LLVM Constant Representation
 class Constant : public User {
+  void operator=(const Constant &);     // Do not implement
+  Constant(const Constant &);           // Do not implement
 protected:
   Constant(const Type *Ty, ValueTy vty, Use *Ops, unsigned NumOps,
            const std::string& Name = "")
@@ -75,7 +94,7 @@ public:
   /// use Value::replaceAllUsesWith, which automatically dispatches to this
   /// method as needed.
   ///
-  virtual void replaceUsesOfWithOnConstant(Value *From, Value *To, Use *U) {
+  virtual void replaceUsesOfWithOnConstant(Value *, Value *, Use *) {
     // Provide a default implementation for constants (like integers) that
     // cannot use any other values.  This cannot be called at runtime, but needs
     // to be here to avoid link errors.
@@ -88,6 +107,13 @@ public:
   /// constant subsystem, which can be used in environments where this memory
   /// is otherwise reported as a leak.
   static void clearAllValueMaps();
+  
+  /// getStringValue - Turn an LLVM constant pointer that eventually points to a
+  /// global into a string value.  Return an empty string if we can't do it.
+  /// Parameter Chop determines if the result is chopped at the first null
+  /// terminator.
+  ///
+  std::string getStringValue(bool Chop = true, unsigned Offset = 0);
 };
 
 } // End llvm namespace