Really, really fix PointerUnion3::is

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

diff --git a/include/llvm/AbstractTypeUser.h b/include/llvm/AbstractTypeUser.h
index ee3fde033eb0345ec261eea48f380b3db8156529..80656d89b726a20f3d5b954dc50eaa4dd3a35fe1 100644 (file)
--- a/include/llvm/AbstractTypeUser.h
+++ b/include/llvm/AbstractTypeUser.h
@@ -2,8 +2,8 @@
 //
 //                     The LLVM Compiler Infrastructure
 //
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
@@ -14,9 +14,11 @@
 #ifndef LLVM_ABSTRACT_TYPE_USER_H
 #define LLVM_ABSTRACT_TYPE_USER_H
 
-// IMPORTANT: Do not include this file directly.  Include Type.h instead.
-// Some versions of GCC can't handle the inlined method PATypeHolder::dropRef()
-// correctly otherwise.
+#if !defined(LLVM_TYPE_H) && !defined(LLVM_VALUE_H)
+#error Do not include this file directly.  Include Type.h instead.
+#error Some versions of GCC (e.g. 3.4 and 4.1) can not handle the inlined method
+#error PATypeHolder::dropRef() correctly otherwise.
+#endif
 
 // This is the "master" include for <cassert> Whether this file needs it or not,
 // it must always include <cassert> for the files which include
@@ -31,6 +33,7 @@ namespace llvm {
 
 class Type;
 class DerivedType;
+template<typename T> struct simplify_type;
 
 /// The AbstractTypeUser class is an interface to be implemented by classes who
 /// could possibly use an abstract type.  Abstract types are denoted by the
@@ -39,7 +42,7 @@ class DerivedType;
 ///
 /// Classes must implement this interface so that they may be notified when an
 /// abstract type is resolved.  Abstract types may be resolved into more 
-/// concrete types through: linking, parsing, and bytecode reading.  When this 
+/// concrete types through: linking, parsing, and bitcode reading.  When this 
 /// happens, all of the users of the type must be updated to reference the new,
 /// more concrete type.  They are notified through the AbstractTypeUser 
 /// interface.
@@ -172,6 +175,21 @@ private:
   void dropRef();
 };
 
+// simplify_type - Allow clients to treat uses just like values when using
+// casting operators.
+template<> struct simplify_type<PATypeHolder> {
+  typedef const Type* SimpleType;
+  static SimpleType getSimplifiedValue(const PATypeHolder &Val) {
+    return static_cast<SimpleType>(Val.get());
+  }
+};
+template<> struct simplify_type<const PATypeHolder> {
+  typedef const Type* SimpleType;
+  static SimpleType getSimplifiedValue(const PATypeHolder &Val) {
+    return static_cast<SimpleType>(Val.get());
+  }
+};
+  
 } // End llvm namespace
 
 #endif