diff --git a/llvm/lib/Transforms/Coroutines/CoroFrame.cpp b/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
index 98f6ca2..174430d 100644
--- a/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
+++ b/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
@@ -52,7 +52,7 @@
   }
 
   size_t blockToIndex(BasicBlock *BB) const {
-    auto *I = std::lower_bound(V.begin(), V.end(), BB);
+    auto *I = llvm::lower_bound(V, BB);
     assert(I != V.end() && *I == BB && "BasicBlockNumberng: Unknown block");
     return I - V.begin();
   }
diff --git a/llvm/lib/Transforms/Scalar/JumpThreading.cpp b/llvm/lib/Transforms/Scalar/JumpThreading.cpp
index 7cb955d..c80cdd0 100644
--- a/llvm/lib/Transforms/Scalar/JumpThreading.cpp
+++ b/llvm/lib/Transforms/Scalar/JumpThreading.cpp
@@ -1480,8 +1480,7 @@
   for (pred_iterator PI = PB; PI != PE; ++PI) {
     BasicBlock *P = *PI;
     AvailablePredsTy::iterator I =
-      std::lower_bound(AvailablePreds.begin(), AvailablePreds.end(),
-                       std::make_pair(P, (Value*)nullptr));
+        llvm::lower_bound(AvailablePreds, std::make_pair(P, (Value *)nullptr));
 
     assert(I != AvailablePreds.end() && I->first == P &&
            "Didn't find entry for predecessor!");
diff --git a/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp b/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
index eeeef58..cf85211 100644
--- a/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
+++ b/llvm/lib/Transforms/Scalar/MemCpyOptimizer.cpp
@@ -278,8 +278,8 @@
                             unsigned Alignment, Instruction *Inst) {
   int64_t End = Start+Size;
 
-  range_iterator I = std::lower_bound(Ranges.begin(), Ranges.end(), Start,
-    [](const MemsetRange &LHS, int64_t RHS) { return LHS.End < RHS; });
+  range_iterator I = llvm::bsearch(
+      Ranges, [=](const MemsetRange &O) { return Start <= O.End; });
 
   // We now know that I == E, in which case we didn't find anything to merge
   // with, or that Start <= I->End.  If End < I->Start or I == E, then we need
diff --git a/llvm/lib/Transforms/Scalar/Reassociate.cpp b/llvm/lib/Transforms/Scalar/Reassociate.cpp
index 1c06ffc..fa8c9e2 100644
--- a/llvm/lib/Transforms/Scalar/Reassociate.cpp
+++ b/llvm/lib/Transforms/Scalar/Reassociate.cpp
@@ -1826,7 +1826,7 @@
     return V;
 
   ValueEntry NewEntry = ValueEntry(getRank(V), V);
-  Ops.insert(std::lower_bound(Ops.begin(), Ops.end(), NewEntry), NewEntry);
+  Ops.insert(llvm::lower_bound(Ops, NewEntry), NewEntry);
   return nullptr;
 }