Small improvements to class lookup cache pass.

opts/ClassLookupCache.cpp

@@ -49,7 +49,7 @@ namespace
         for (BasicBlock::iterator b=i->begin(), last=i->end() ;
             b != last ; ++b) {
           if (CallInst *call = dyn_cast<CallInst>(b)) {
-            if (Function *func = call->getCalledFunction()) {
+            if (Function *func = dyn_cast<Function>(call->getCalledValue()->stripPointerCasts())) {
               if (func->getName() == "objc_lookup_class") {
                 ClassLookup lookup;
                 GlobalVariable *classNameVar = dyn_cast<GlobalVariable>(
@@ -78,7 +78,6 @@ namespace
         std::string &cls = i->second;
         LLVMType *clsTy = lookup->getType();
         Value *global = M->getGlobalVariable(("_OBJC_CLASS_" + i->second).c_str(), true);
-        global = 0;
         // If we can see the class reference for this, then reference it
         // directly.  If not, then do the lookup and cache it.
         if (global) {
@@ -87,6 +86,7 @@ namespace
           Value *cls = new BitCastInst(global, clsTy, "class", lookup);
           lookup->replaceAllUsesWith(cls);
           lookup->removeFromParent();
+          delete lookup;
         } else {
           GlobalVariable *cache = statics[cls];
           if (!cache) {