assert(0) -> LLVM_UNREACHABLE.

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

diff --git a/include/llvm/Constant.h b/include/llvm/Constant.h
index d85771a09a47018ee1bba007e0ac0d2cb8ef67dd..d4949d1a0ffd1447f2ea7a86fcab3518e238af12 100644 (file)
--- a/include/llvm/Constant.h
+++ b/include/llvm/Constant.h
@@ -17,6 +17,21 @@
 #include "llvm/User.h"
 
 namespace llvm {
+  template<typename T> class SmallVectorImpl;
+
+  /// If object contains references to other objects, then relocations are
+  /// usually required for emission of such object (especially in PIC mode). One
+  /// usually distinguishes local and global relocations. Local relocations are
+  /// made wrt objects in the same module and these objects have local (internal
+  /// or private) linkage. Global relocations are made wrt externally visible
+  /// objects. In most cases local relocations can be resolved via so-called
+  /// 'pre-link' technique.
+  namespace Reloc {
+    const unsigned None   = 0;
+    const unsigned Local  = 1 << 0; ///< Local relocations are required
+    const unsigned Global = 1 << 1; ///< Global relocations are required
+    const unsigned LocalOrGlobal = Local | Global;
+  }
 
 /// 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
@@ -32,7 +47,7 @@ namespace llvm {
 /// 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 
+/// Constants 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 {
@@ -57,18 +72,17 @@ public:
   /// getNullValue.
   virtual bool isNullValue() const = 0;
 
-  virtual void print(std::ostream &O) const;
-  void print(std::ostream *O) const { if (O) print(*O); }
-  
   /// canTrap - Return true if evaluation of this constant could trap.  This is
   /// true for things like constant expressions that could divide by zero.
   bool canTrap() const;
 
-  /// ContaintsRelocations - Return true if the constant value contains
-  /// relocations which cannot be resolved at compile time.
-  bool ContainsRelocations() const;
+  /// ContainsRelocations - Return true if the constant value contains
+  /// relocations which cannot be resolved at compile time. Note that answer is
+  /// not exclusive: there can be possibility that relocations of other kind are
+  /// required as well.
+  bool ContainsRelocations(unsigned Kind = Reloc::LocalOrGlobal) const;
 
-  // Specialize get/setOperand for Constant's as their operands are always
+  // Specialize get/setOperand for Constants as their operands are always
   // constants as well.
   Constant *getOperand(unsigned i) {
     return static_cast<Constant*>(User::getOperand(i));
@@ -79,6 +93,12 @@ public:
   void setOperand(unsigned i, Constant *C) {
     User::setOperand(i, C);
   }
+  
+  /// getVectorElements - This method, which is only valid on constant of vector
+  /// type, returns the elements of the vector in the specified smallvector.
+  /// This handles breaking down a vector undef into undef elements, etc.  For
+  /// constant exprs and other cases we can't handle, we return an empty vector.
+  void getVectorElements(SmallVectorImpl<Constant*> &Elts) const;
 
   /// destroyConstant - Called if some element of this constant is no longer
   /// valid.  At this point only other constants may be on the use_list for this
@@ -115,13 +135,6 @@ public:
            "implemented for all constants that have operands!");
     assert(0 && "Constants that do not have operands cannot be using 'From'!");
   }
-
-  /// 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