<< Cost << "\n");
return false;
}
-
+
// If this is a trivial condition to unswitch (which results in no code
// duplication), do it now.
Constant *CondVal;
// If the successor only has a single pred, split the top of the successor
// block.
assert(SP == BB && "CFG broken");
+
+ // If this block has a single predecessor, remove any phi nodes. Unswitch
+ // expect that, after split the edges from inside the loop to the exit
+ // block, that there will be no phi nodes in the new exit block. Single
+ // entry phi nodes break this assumption.
+ BasicBlock::iterator I = Succ->begin();
+ while (PHINode *PN = dyn_cast<PHINode>(I)) {
+ PN->replaceAllUsesWith(PN->getIncomingValue(0));
+ PN->eraseFromParent();
+ I = Succ->begin();
+ }
+
return SplitBlock(Succ, Succ->begin());
} else {
// Otherwise, if BB has a single successor, split it at the bottom of the