diff --git a/llvm/include/llvm/Analysis/StackSafetyAnalysis.h b/llvm/include/llvm/Analysis/StackSafetyAnalysis.h
--- a/llvm/include/llvm/Analysis/StackSafetyAnalysis.h
+++ b/llvm/include/llvm/Analysis/StackSafetyAnalysis.h
@@ -15,6 +15,7 @@
 
 #include "llvm/IR/PassManager.h"
 #include "llvm/Pass.h"
+#include "llvm/IR/Instructions.h"
 
 namespace llvm {
 
@@ -35,6 +36,8 @@
 
   // TODO: Add useful for client methods.
   void print(raw_ostream &O) const;
+  bool isSafe(const AllocaInst *AI) const;
+  uint64_t getSizeOf(const AllocaInst *AI) const;
 };
 
 /// StackSafetyInfo wrapper for the new pass manager.
diff --git a/llvm/lib/Analysis/StackSafetyAnalysis.cpp b/llvm/lib/Analysis/StackSafetyAnalysis.cpp
--- a/llvm/lib/Analysis/StackSafetyAnalysis.cpp
+++ b/llvm/lib/Analysis/StackSafetyAnalysis.cpp
@@ -146,7 +146,7 @@
   // May be a Function or a GlobalAlias
   const GlobalValue *GV = nullptr;
   // Informations about allocas uses.
-  SmallVector<AllocaInfo, 4> Allocas;
+  DenseMap<const AllocaInst*, AllocaInfo> Allocas;
   // Informations about parameters uses.
   SmallVector<ParamInfo, 4> Params;
   // TODO: describe return value as depending on one or more of its arguments.
@@ -178,7 +178,7 @@
       O << "      " << P << "\n";
     O << "    allocas uses:\n";
     for (auto &AS : Allocas)
-      O << "      " << AS << "\n";
+      O << "      " << AS.second << "\n";
   }
 
 private:
@@ -372,9 +372,10 @@
 
   for (auto &I : instructions(F)) {
     if (auto AI = dyn_cast<AllocaInst>(&I)) {
-      Info.Allocas.emplace_back(PointerSize, AI,
-                                getStaticAllocaAllocationSize(AI));
-      AllocaInfo &AS = Info.Allocas.back();
+      auto inserted = Info.Allocas.insert(std::make_pair(
+          AI, AllocaInfo{PointerSize, AI, getStaticAllocaAllocationSize(AI)}));
+      // Obtain the AllocaInfo
+      AllocaInfo &AS = inserted.first->second; 
       analyzeAllUses(AI, AS.Use);
     }
   }
@@ -481,7 +482,7 @@
   bool UpdateToFullSet = FS.UpdateCount > StackSafetyMaxIterations;
   bool Changed = false;
   for (auto &AS : FS.Allocas)
-    Changed |= updateOneUse(AS.Use, UpdateToFullSet);
+    Changed |= updateOneUse(AS.second.Use, UpdateToFullSet);
   for (auto &PS : FS.Params)
     Changed |= updateOneUse(PS.Use, UpdateToFullSet);
 
@@ -506,7 +507,7 @@
     Callees.clear();
     StackSafetyInfo::FunctionInfo &FS = F.second;
     for (auto &AS : FS.Allocas)
-      for (auto &CS : AS.Use.Calls)
+      for (auto &CS : AS.second.Use.Calls)
         Callees.push_back(CS.Callee);
     for (auto &PS : FS.Params)
       for (auto &CS : PS.Use.Calls)
@@ -575,6 +576,28 @@
 
 void StackSafetyInfo::print(raw_ostream &O) const { Info->print(O); }
 
+bool StackSafetyInfo::isSafe(const AllocaInst *AI) const {
+  auto iter = Info->Allocas.find(AI);
+  assert(iter != Info->Allocas.end() && "The specified AllocaInst is not a part of this function");
+
+  auto &UI = iter->second.Use;
+  if (UI.Range.isFullSet()) // FullSet indicates that the analysis cannot prove the safety of the alloca
+    return false;
+  else if (UI.Range.getLower().getLimitedValue() < 0)
+    return false;
+  else if (UI.Range.getUpper().getLimitedValue() > iter->second.Size)
+    return false;
+  return true;
+}
+
+uint64_t StackSafetyInfo::getSizeOf(const AllocaInst *AI) const {
+  auto iter = Info->Allocas.find(AI);
+  assert(iter != Info->Allocas.end() &&
+         "The specified AllocaInst is not a part of this function");
+
+  return iter->second.Size;
+}
+
 AnalysisKey StackSafetyAnalysis::Key;
 
 StackSafetyInfo StackSafetyAnalysis::run(Function &F,