diff --git a/llvm/lib/Transforms/IPO/Inliner.cpp b/llvm/lib/Transforms/IPO/Inliner.cpp
--- a/llvm/lib/Transforms/IPO/Inliner.cpp
+++ b/llvm/lib/Transforms/IPO/Inliner.cpp
@@ -64,6 +64,7 @@
 #include "llvm/Transforms/Utils/ModuleUtils.h"
 #include <algorithm>
 #include <cassert>
+#include <deque>
 #include <functional>
 #include <sstream>
 #include <tuple>
@@ -670,40 +671,55 @@
   return *IAA->getAdvisor();
 }
 
-class InlineOrder {
+template <typename T, typename Container> class InlineOrder {
 public:
-  using T = std::pair<CallBase *, int>;
-  using iterator = T *;
-  using const_iterator = const T *;
-  using reference = T &;
+  using iterator = typename Container::iterator;
+  using const_iterator = typename Container::const_iterator;
+  using reference = typename Container::reference;
 
   virtual ~InlineOrder() {}
 
   virtual size_t size() = 0;
-  virtual reference operator[](size_t idx) = 0;
-  virtual void push_back(const T &Elt) = 0;
-  virtual T pop() = 0;
+
+  virtual void push(const T &Elt) = 0;
+
+  virtual void pop() = 0;
+
+  virtual reference front() = 0;
+
   virtual iterator erase(const_iterator B, const_iterator E) = 0;
+
   virtual iterator begin() = 0;
   virtual iterator end() = 0;
 
   bool empty() { return !size(); }
 };
 
-class DefaultInlineOrder : public InlineOrder {
+template <typename T, typename Container = std::deque<T>>
+class DefaultInlineOrder : public InlineOrder<T, Container> {
+  using Base = InlineOrder<T, Container>;
+  using iterator = typename Base::iterator;
+  using const_iterator = typename Base::const_iterator;
+  using reference = typename Base::reference;
+
 public:
   size_t size() override { return Calls.size(); }
-  reference operator[](size_t idx) override { return Calls[idx]; }
-  void push_back(const T &Elt) override { Calls.push_back(Elt); }
-  T pop() override { return Calls.pop_back_val(); }
+
+  void push(const T &Elt) override { Calls.push_back(Elt); }
+
+  void pop() override { Calls.pop_front(); }
+
+  reference front() override { return Calls.front(); }
+
   iterator erase(const_iterator CB, const_iterator CE) override {
     return Calls.erase(CB, CE);
   }
+
   iterator begin() override { return Calls.begin(); }
   iterator end() override { return Calls.end(); }
 
 private:
-  SmallVector<T, 16> Calls;
+  Container Calls;
 };
 
 PreservedAnalyses InlinerPass::run(LazyCallGraph::SCC &InitialC,
@@ -750,7 +766,7 @@
   // this model, but it is uniformly spread across all the functions in the SCC
   // and eventually they all become too large to inline, rather than
   // incrementally maknig a single function grow in a super linear fashion.
-  DefaultInlineOrder Calls;
+  DefaultInlineOrder<std::pair<CallBase *, int>> Calls;
 
   // Populate the initial list of calls in this SCC.
   for (auto &N : InitialC) {
@@ -765,7 +781,7 @@
       if (auto *CB = dyn_cast<CallBase>(&I))
         if (Function *Callee = CB->getCalledFunction()) {
           if (!Callee->isDeclaration())
-            Calls.push_back({CB, -1});
+            Calls.push({CB, -1});
           else if (!isa<IntrinsicInst>(I)) {
             using namespace ore;
             setInlineRemark(*CB, "unavailable definition");
@@ -802,12 +818,12 @@
 
   // Loop forward over all of the calls. Note that we cannot cache the size as
   // inlining can introduce new calls that need to be processed.
-  for (int I = 0; I < (int)Calls.size(); ++I) {
+  while (!Calls.empty()) {
     // We expect the calls to typically be batched with sequences of calls that
     // have the same caller, so we first set up some shared infrastructure for
     // this caller. We also do any pruning we can at this layer on the caller
     // alone.
-    Function &F = *Calls[I].first->getCaller();
+    Function &F = *(Calls.front()).first->getCaller();
     LazyCallGraph::Node &N = *CG.lookup(F);
     if (CG.lookupSCC(N) != C)
       continue;
@@ -824,8 +840,9 @@
     // We bail out as soon as the caller has to change so we can update the
     // call graph and prepare the context of that new caller.
     bool DidInline = false;
-    for (; I < (int)Calls.size() && Calls[I].first->getCaller() == &F; ++I) {
-      auto &P = Calls[I];
+    while (!Calls.empty() && Calls.front().first->getCaller() == &F) {
+      auto &P = Calls.front();
+      Calls.pop();
       CallBase *CB = P.first;
       const int InlineHistoryID = P.second;
       Function &Callee = *CB->getCalledFunction();
@@ -895,7 +912,7 @@
           }
           if (NewCallee)
             if (!NewCallee->isDeclaration())
-              Calls.push_back({ICB, NewHistoryID});
+              Calls.push({ICB, NewHistoryID});
         }
       }
 
@@ -913,7 +930,7 @@
         Callee.removeDeadConstantUsers();
         if (Callee.use_empty() && !CG.isLibFunction(Callee)) {
           Calls.erase(
-              std::remove_if(Calls.begin() + I + 1, Calls.end(),
+              std::remove_if(Calls.begin(), Calls.end(),
                              [&](const std::pair<CallBase *, int> &Call) {
                                return Call.first->getCaller() == &Callee;
                              }),
@@ -935,10 +952,6 @@
         Advice->recordInlining();
     }
 
-    // Back the call index up by one to put us in a good position to go around
-    // the outer loop.
-    --I;
-
     if (!DidInline)
       continue;
     Changed = true;