Revert "address comments"

This reverts commit 790e7ede98c32b4a8c2f0fa69a2817edfc63e475.

Author: c-rhodes

llvm/lib/Transforms/InstCombine/InstructionCombining.cpp

@@ -4983,13 +4983,11 @@ InstCombinerImpl::pushFreezeToPreventPoisonFromPropagating(FreezeInst &OrigFI) {
     if (auto *PN = dyn_cast<PHINode>(V)) {
       BasicBlock *BB = PN->getParent();
       SmallPtrSet<BasicBlock *, 8> VisitedBBs;
-      for (unsigned I = 0; I < PN->getNumIncomingValues(); ++I) {
-        Value *InV = PN->getIncomingValue(I);
-        BasicBlock *InBB = PN->getIncomingBlock(I);
-
+      for (Use &U : PN->incoming_values()) {
+        BasicBlock *InBB = PN->getIncomingBlock(U);
         // We can't move freeze if the start value is the result of a
         // terminator (e.g. an invoke).
-        if (auto *OpI = dyn_cast<Instruction>(InV)) {
+        if (auto *OpI = dyn_cast<Instruction>(U)) {
           if (OpI->isTerminator())
             return false;
         }
@@ -4999,7 +4997,7 @@ InstCombinerImpl::pushFreezeToPreventPoisonFromPropagating(FreezeInst &OrigFI) {
         // invalidating the iterator. We simply don't support this case, but it
         // could be handled if there's a use case.
         if (isBackEdge(InBB, BB) || !VisitedBBs.insert(InBB).second ||
-            match(InV, m_Undef()))
+            match(U.get(), m_Undef()))
           return false;
         VisitedBBs.insert(InBB);
       }