[llvm-commits] [llvm] r48255 - in /llvm/trunk: include/llvm/GlobalAlias.h lib/VMCore/Globals.cpp

[Anton Korobeynikov]

Author: asl
Date: Tue Mar 11 17:28:56 2008
New Revision: 48255

URL: http://llvm.org/viewvc/llvm-project?rev=48255&view=rev
Log:
Add helper for ultimate aliasee resoltion

Modified:
    llvm/trunk/include/llvm/GlobalAlias.h
    llvm/trunk/lib/VMCore/Globals.cpp

Modified: llvm/trunk/include/llvm/GlobalAlias.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/GlobalAlias.h?rev=48255&r1=48254&r2=48255&view=diff

==============================================================================
--- llvm/trunk/include/llvm/GlobalAlias.h (original)
+++ llvm/trunk/include/llvm/GlobalAlias.h Tue Mar 11 17:28:56 2008
@@ -78,7 +78,12 @@
   /// getAliasedGlobal() - Aliasee can be either global or bitcast of
   /// global. This method retrives the global for both aliasee flavours.
   const GlobalValue* getAliasedGlobal() const;
-    
+
+  /// resolveAliasedGlobal() - This method tries to ultimately resolve alias by
+  /// going through aliasing chain and trying to find the very last
+  /// global. Return NULL is cycle was found.
+  const GlobalValue* resolveAliasedGlobal() const;
+
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const GlobalAlias *) { return true; }
   static inline bool classof(const Value *V) {

Modified: llvm/trunk/lib/VMCore/Globals.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/VMCore/Globals.cpp?rev=48255&r1=48254&r2=48255&view=diff

==============================================================================
--- llvm/trunk/lib/VMCore/Globals.cpp (original)
+++ llvm/trunk/lib/VMCore/Globals.cpp Tue Mar 11 17:28:56 2008
@@ -17,6 +17,7 @@
 #include "llvm/GlobalAlias.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Module.h"
+#include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/Support/LeakDetector.h"
 using namespace llvm;
 
@@ -230,3 +231,18 @@
   return 0;
 }
 
+const GlobalValue *GlobalAlias::resolveAliasedGlobal() const {
+  SmallPtrSet<const GlobalValue*, 1> Visited;
+
+  const GlobalValue *GV = getAliasedGlobal();
+  Visited.insert(GV);
+
+  while (const GlobalAlias *GA = dyn_cast<GlobalAlias>(GV)) {
+    GV = GA->getAliasedGlobal();
+
+    if (!Visited.insert(GV))
+      return NULL;
+  }
+
+  return GV;
+}