// Arguments and constants dominate all instructions.
return true;
+ // If we are processing instructions (and/or basic blocks) that have not been
+ // fully added to a function, the parent nodes may still be null. Simply
+ // return the conservative answer in these cases.
+ if (!I->getParent() || !P->getParent() || !I->getParent()->getParent())
+ return false;
+
// If we have a DominatorTree then do a precise test.
if (DT) {
if (!DT->isReachableFromEntry(P->getParent()))