diff --git a/include/llvm/IR/BasicBlock.h b/include/llvm/IR/BasicBlock.h
index b780fd6..fd9efb8 100644
--- a/include/llvm/IR/BasicBlock.h
+++ b/include/llvm/IR/BasicBlock.h
@@ -362,7 +362,7 @@
   /// This is actually not used to update the Predecessor list, but is actually
   /// used to update the PHI nodes that reside in the block.  Note that this
   /// should be called while the predecessor still refers to this block.
-  void removePredecessor(BasicBlock *Pred, bool DontDeleteUselessPHIs = false);
+  void removePredecessor(BasicBlock *Pred, bool KeepOneInputPHIs = false);
 
   bool canSplitPredecessors() const;
 
diff --git a/include/llvm/Transforms/Utils/BasicBlockUtils.h b/include/llvm/Transforms/Utils/BasicBlockUtils.h
index c264aae..4e76328 100644
--- a/include/llvm/Transforms/Utils/BasicBlockUtils.h
+++ b/include/llvm/Transforms/Utils/BasicBlockUtils.h
@@ -41,25 +41,25 @@
 
 /// Replace contents of every block in \p BBs with single unreachable
 /// instruction. If \p Updates is specified, collect all necessary DT updates
-/// into this vector. If \p DontDeleteUselessPHIs is true, one-input Phis in
+/// into this vector. If \p KeepOneInputPHIs is true, one-input Phis in
 /// successors of blocks being deleted will be preserved.
 void DetatchDeadBlocks(ArrayRef <BasicBlock *> BBs,
                        SmallVectorImpl<DominatorTree::UpdateType> *Updates,
-                       bool DontDeleteUselessPHIs = false);
+                       bool KeepOneInputPHIs = false);
 
 /// Delete the specified block, which must have no predecessors.
 void DeleteDeadBlock(BasicBlock *BB, DomTreeUpdater *DTU = nullptr,
-                     bool DontDeleteUselessPHIs = false);
+                     bool KeepOneInputPHIs = false);
 
 /// Delete the specified blocks from \p BB. The set of deleted blocks must have
 /// no predecessors that are not being deleted themselves. \p BBs must have no
 /// duplicating blocks. If there are loops among this set of blocks, all
 /// relevant loop info updates should be done before this function is called.
-/// If \p DontDeleteUselessPHIs is true, one-input Phis in successors of blocks
+/// If \p KeepOneInputPHIs is true, one-input Phis in successors of blocks
 /// being deleted will be preserved.
 void DeleteDeadBlocks(ArrayRef <BasicBlock *> BBs,
                       DomTreeUpdater *DTU = nullptr,
-                      bool DontDeleteUselessPHIs = false);
+                      bool KeepOneInputPHIs = false);
 
 /// We know that BB has one predecessor. If there are any single-entry PHI nodes
 /// in it, fold them away. This handles the case when all entries to the PHI
@@ -106,7 +106,7 @@
   LoopInfo *LI;
   MemorySSAUpdater *MSSAU;
   bool MergeIdenticalEdges = false;
-  bool DontDeleteUselessPHIs = false;
+  bool KeepOneInputPHIs = false;
   bool PreserveLCSSA = false;
 
   CriticalEdgeSplittingOptions(DominatorTree *DT = nullptr,
@@ -119,8 +119,8 @@
     return *this;
   }
 
-  CriticalEdgeSplittingOptions &setDontDeleteUselessPHIs() {
-    DontDeleteUselessPHIs = true;
+  CriticalEdgeSplittingOptions &setKeepOneInputPHIs() {
+    KeepOneInputPHIs = true;
     return *this;
   }
 
diff --git a/lib/IR/BasicBlock.cpp b/lib/IR/BasicBlock.cpp
index eee4d18..18e2fd8 100644
--- a/lib/IR/BasicBlock.cpp
+++ b/lib/IR/BasicBlock.cpp
@@ -299,7 +299,7 @@
 /// called while the predecessor still refers to this block.
 ///
 void BasicBlock::removePredecessor(BasicBlock *Pred,
-                                   bool DontDeleteUselessPHIs) {
+                                   bool KeepOneInputPHIs) {
   assert((hasNUsesOrMore(16)||// Reduce cost of this assertion for complex CFGs.
           find(pred_begin(this), pred_end(this), Pred) != pred_end(this)) &&
          "removePredecessor: BB is not a predecessor!");
@@ -330,11 +330,11 @@
   }
 
   // <= Two predecessors BEFORE I remove one?
-  if (max_idx <= 2 && !DontDeleteUselessPHIs) {
+  if (max_idx <= 2 && !KeepOneInputPHIs) {
     // Yup, loop through and nuke the PHI nodes
     while (PHINode *PN = dyn_cast<PHINode>(&front())) {
       // Remove the predecessor first.
-      PN->removeIncomingValue(Pred, !DontDeleteUselessPHIs);
+      PN->removeIncomingValue(Pred, !KeepOneInputPHIs);
 
       // If the PHI _HAD_ two uses, replace PHI node with its now *single* value
       if (max_idx == 2) {
@@ -359,7 +359,7 @@
       // If all incoming values to the Phi are the same, we can replace the Phi
       // with that value.
       Value* PNV = nullptr;
-      if (!DontDeleteUselessPHIs && (PNV = PN->hasConstantValue()))
+      if (!KeepOneInputPHIs && (PNV = PN->hasConstantValue()))
         if (PNV != PN) {
           PN->replaceAllUsesWith(PNV);
           PN->eraseFromParent();
diff --git a/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
index 04a2505..a153301 100644
--- a/lib/Transforms/Scalar/LoopStrengthReduce.cpp
+++ b/lib/Transforms/Scalar/LoopStrengthReduce.cpp
@@ -5292,7 +5292,7 @@
             NewBB = SplitCriticalEdge(BB, Parent,
                                       CriticalEdgeSplittingOptions(&DT, &LI)
                                           .setMergeIdenticalEdges()
-                                          .setDontDeleteUselessPHIs());
+                                          .setKeepOneInputPHIs());
           } else {
             SmallVector<BasicBlock*, 2> NewBBs;
             SplitLandingPadPredecessors(Parent, BB, "", "", NewBBs, &DT, &LI);
diff --git a/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp b/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
index 8113427..db7da8e 100644
--- a/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
+++ b/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
@@ -761,7 +761,7 @@
         continue;
       }
       CommonSuccBB->removePredecessor(BB,
-                                      /*DontDeleteUselessPHIs*/ true);
+                                      /*KeepOneInputPHIs*/ true);
     }
     // Now nuke the switch and replace it with a direct branch.
     SI.eraseFromParent();
@@ -1069,7 +1069,7 @@
       continue;
 
     ClonedSuccBB->removePredecessor(ClonedParentBB,
-                                    /*DontDeleteUselessPHIs*/ true);
+                                    /*KeepOneInputPHIs*/ true);
   }
 
   // Replace the cloned branch with an unconditional branch to the cloned
@@ -2078,7 +2078,7 @@
              "Only one possible unswitched block for a branch!");
       BasicBlock *UnswitchedSuccBB = *UnswitchedSuccBBs.begin();
       UnswitchedSuccBB->removePredecessor(ParentBB,
-                                          /*DontDeleteUselessPHIs*/ true);
+                                          /*KeepOneInputPHIs*/ true);
       DTUpdates.push_back({DominatorTree::Delete, ParentBB, UnswitchedSuccBB});
     } else {
       // Note that we actually want to remove the parent block as a predecessor
@@ -2093,7 +2093,7 @@
       for (auto &Case : NewSI->cases())
         Case.getCaseSuccessor()->removePredecessor(
             ParentBB,
-            /*DontDeleteUselessPHIs*/ true);
+            /*KeepOneInputPHIs*/ true);
 
       // We need to use the set to populate domtree updates as even when there
       // are multiple cases pointing at the same successor we only want to
diff --git a/lib/Transforms/Utils/BasicBlockUtils.cpp b/lib/Transforms/Utils/BasicBlockUtils.cpp
index c0148b9..5ca9222 100644
--- a/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -50,13 +50,13 @@
 void llvm::DetatchDeadBlocks(
     ArrayRef<BasicBlock *> BBs,
     SmallVectorImpl<DominatorTree::UpdateType> *Updates,
-    bool DontDeleteUselessPHIs) {
+    bool KeepOneInputPHIs) {
   for (auto *BB : BBs) {
     // Loop through all of our successors and make sure they know that one
     // of their predecessors is going away.
     SmallPtrSet<BasicBlock *, 4> UniqueSuccessors;
     for (BasicBlock *Succ : successors(BB)) {
-      Succ->removePredecessor(BB, DontDeleteUselessPHIs);
+      Succ->removePredecessor(BB, KeepOneInputPHIs);
       if (Updates && UniqueSuccessors.insert(Succ).second)
         Updates->push_back({DominatorTree::Delete, BB, Succ});
     }
@@ -82,12 +82,12 @@
 }
 
 void llvm::DeleteDeadBlock(BasicBlock *BB, DomTreeUpdater *DTU,
-                           bool DontDeleteUselessPHIs) {
-  DeleteDeadBlocks({BB}, DTU, DontDeleteUselessPHIs);
+                           bool KeepOneInputPHIs) {
+  DeleteDeadBlocks({BB}, DTU, KeepOneInputPHIs);
 }
 
 void llvm::DeleteDeadBlocks(ArrayRef <BasicBlock *> BBs, DomTreeUpdater *DTU,
-                            bool DontDeleteUselessPHIs) {
+                            bool KeepOneInputPHIs) {
 #ifndef NDEBUG
   // Make sure that all predecessors of each dead block is also dead.
   SmallPtrSet<BasicBlock *, 4> Dead(BBs.begin(), BBs.end());
@@ -98,7 +98,7 @@
 #endif
 
   SmallVector<DominatorTree::UpdateType, 4> Updates;
-  DetatchDeadBlocks(BBs, DTU ? &Updates : nullptr, DontDeleteUselessPHIs);
+  DetatchDeadBlocks(BBs, DTU ? &Updates : nullptr, KeepOneInputPHIs);
 
   if (DTU)
     DTU->applyUpdates(Updates, /*ForceRemoveDuplicates*/ true);
diff --git a/lib/Transforms/Utils/BreakCriticalEdges.cpp b/lib/Transforms/Utils/BreakCriticalEdges.cpp
index d73fefd..2944c37 100644
--- a/lib/Transforms/Utils/BreakCriticalEdges.cpp
+++ b/lib/Transforms/Utils/BreakCriticalEdges.cpp
@@ -192,7 +192,7 @@
       if (TI->getSuccessor(i) != DestBB) continue;
 
       // Remove an entry for TIBB from DestBB phi nodes.
-      DestBB->removePredecessor(TIBB, Options.DontDeleteUselessPHIs);
+      DestBB->removePredecessor(TIBB, Options.KeepOneInputPHIs);
 
       // We found another edge to DestBB, go to NewBB instead.
       TI->setSuccessor(i, NewBB);
diff --git a/lib/Transforms/Utils/LoopSimplify.cpp b/lib/Transforms/Utils/LoopSimplify.cpp
index 954e803..ca29f67 100644
--- a/lib/Transforms/Utils/LoopSimplify.cpp
+++ b/lib/Transforms/Utils/LoopSimplify.cpp
@@ -662,9 +662,9 @@
       DT->eraseNode(ExitingBlock);
 
       BI->getSuccessor(0)->removePredecessor(
-          ExitingBlock, /* DontDeleteUselessPHIs */ PreserveLCSSA);
+          ExitingBlock, /* KeepOneInputPHIs */ PreserveLCSSA);
       BI->getSuccessor(1)->removePredecessor(
-          ExitingBlock, /* DontDeleteUselessPHIs */ PreserveLCSSA);
+          ExitingBlock, /* KeepOneInputPHIs */ PreserveLCSSA);
       ExitingBlock->eraseFromParent();
     }
   }
diff --git a/lib/Transforms/Utils/SimplifyCFG.cpp b/lib/Transforms/Utils/SimplifyCFG.cpp
index 00bcb84..dbd8fb7 100644
--- a/lib/Transforms/Utils/SimplifyCFG.cpp
+++ b/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -3436,7 +3436,7 @@
       KeepEdge2 = nullptr;
     else
       Succ->removePredecessor(OldTerm->getParent(),
-                              /*DontDeleteUselessPHIs=*/true);
+                              /*KeepOneInputPHIs=*/true);
   }
 
   IRBuilder<> Builder(OldTerm);
@@ -5433,7 +5433,7 @@
     // We cached PHINodes in PHIs. To avoid accessing deleted PHINodes later,
     // do not delete PHINodes here.
     SI->getDefaultDest()->removePredecessor(SI->getParent(),
-                                            /*DontDeleteUselessPHIs=*/true);
+                                            /*KeepOneInputPHIs=*/true);
   }
 
   bool ReturnedEarly = false;