Index: include/llvm/Analysis/TargetTransformInfo.h
===================================================================
--- include/llvm/Analysis/TargetTransformInfo.h
+++ include/llvm/Analysis/TargetTransformInfo.h
@@ -388,6 +388,9 @@
   /// operations, shuffles, or casts.
   bool isFPVectorizationPotentiallyUnsafe() const;
 
+  /// \brief Indicate whether target allows misaligned memory accesses
+  bool allowsMisalignedMemoryAccesses(unsigned BitWidth) const;
+
   /// \brief Return hardware support for population count.
   PopcntSupportKind getPopcntSupport(unsigned IntTyWidthInBit) const;
 
@@ -653,6 +656,7 @@
   virtual bool enableAggressiveInterleaving(bool LoopHasReductions) = 0;
   virtual bool enableInterleavedAccessVectorization() = 0;
   virtual bool isFPVectorizationPotentiallyUnsafe() = 0;
+  virtual bool allowsMisalignedMemoryAccesses(unsigned BitWidth) = 0;
   virtual PopcntSupportKind getPopcntSupport(unsigned IntTyWidthInBit) = 0;
   virtual bool haveFastSqrt(Type *Ty) = 0;
   virtual int getFPOpCost(Type *Ty) = 0;
@@ -820,6 +824,9 @@
   bool isFPVectorizationPotentiallyUnsafe() override {
     return Impl.isFPVectorizationPotentiallyUnsafe();
   }
+  bool allowsMisalignedMemoryAccesses(unsigned BitWidth) override {
+    return Impl.allowsMisalignedMemoryAccesses(BitWidth);
+  }
   PopcntSupportKind getPopcntSupport(unsigned IntTyWidthInBit) override {
     return Impl.getPopcntSupport(IntTyWidthInBit);
   }
Index: include/llvm/Analysis/TargetTransformInfoImpl.h
===================================================================
--- include/llvm/Analysis/TargetTransformInfoImpl.h
+++ include/llvm/Analysis/TargetTransformInfoImpl.h
@@ -244,6 +244,8 @@
 
   bool isFPVectorizationPotentiallyUnsafe() { return false; }
 
+  bool allowsMisalignedMemoryAccesses(unsigned BitWidth) { return false; }
+
   TTI::PopcntSupportKind getPopcntSupport(unsigned IntTyWidthInBit) {
     return TTI::PSK_Software;
   }
Index: include/llvm/CodeGen/BasicTTIImpl.h
===================================================================
--- include/llvm/CodeGen/BasicTTIImpl.h
+++ include/llvm/CodeGen/BasicTTIImpl.h
@@ -105,6 +105,10 @@
 
   /// \name Scalar TTI Implementations
   /// @{
+  bool allowsMisalignedMemoryAccesses(unsigned BitWidth) const {
+    MVT M = MVT::getIntegerVT(BitWidth);
+    return getTLI()->allowsMisalignedMemoryAccesses(M);
+  }
 
   bool hasBranchDivergence() { return false; }
 
Index: lib/Analysis/TargetTransformInfo.cpp
===================================================================
--- lib/Analysis/TargetTransformInfo.cpp
+++ lib/Analysis/TargetTransformInfo.cpp
@@ -181,6 +181,10 @@
   return TTIImpl->isFPVectorizationPotentiallyUnsafe();
 }
 
+bool TargetTransformInfo::allowsMisalignedMemoryAccesses(unsigned BitWidth) const {
+  return TTIImpl->allowsMisalignedMemoryAccesses(BitWidth);
+}
+
 TargetTransformInfo::PopcntSupportKind
 TargetTransformInfo::getPopcntSupport(unsigned IntTyWidthInBit) const {
   return TTIImpl->getPopcntSupport(IntTyWidthInBit);
Index: lib/Transforms/Vectorize/LoadStoreVectorizer.cpp
===================================================================
--- lib/Transforms/Vectorize/LoadStoreVectorizer.cpp
+++ lib/Transforms/Vectorize/LoadStoreVectorizer.cpp
@@ -128,6 +128,9 @@
 
   /// Vectorizes the store instructions in Chain.
   bool vectorizeStoreChain(ArrayRef<Value *> Chain);
+
+  /// Query target for allowed misaligned accesses
+  bool allowsMisaligned(unsigned SzInBytes);
 };
 
 class LoadStoreVectorizer : public FunctionPass {
@@ -155,14 +158,14 @@
 }
 
 INITIALIZE_PASS_BEGIN(LoadStoreVectorizer, DEBUG_TYPE,
-                      "Vectorize load and Store instructions", false, false);
+                      "Vectorize load and Store instructions", false, false)
 INITIALIZE_PASS_DEPENDENCY(SCEVAAWrapperPass)
 INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
 INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
 INITIALIZE_PASS_DEPENDENCY(GlobalsAAWrapperPass)
 INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
 INITIALIZE_PASS_END(LoadStoreVectorizer, DEBUG_TYPE,
-                    "Vectorize load and store instructions", false, false);
+                    "Vectorize load and store instructions", false, false)
 
 char LoadStoreVectorizer::ID = 0;
 
@@ -694,8 +697,9 @@
   unsigned Alignment = getAlignment(S0);
 
   // If the store is going to be misaligned, don't vectorize it.
-  // TODO: Check TLI.allowsMisalignedMemoryAccess
-  if ((Alignment % SzInBytes) != 0 && (Alignment % TargetBaseAlign) != 0) {
+  // TODO: Remove TargetBaseAlign
+  if (allowsMisaligned(SzInBytes) == 0 &&
+      (Alignment % SzInBytes) != 0 && (Alignment % TargetBaseAlign) != 0) {
     if (S0->getPointerAddressSpace() == 0) {
       // If we're storing to an object on the stack, we control its alignment,
       // so we can cheat and change it!
@@ -822,8 +826,9 @@
   unsigned Alignment = getAlignment(L0);
 
   // If the load is going to be misaligned, don't vectorize it.
-  // TODO: Check TLI.allowsMisalignedMemoryAccess and remove TargetBaseAlign.
-  if ((Alignment % SzInBytes) != 0 && (Alignment % TargetBaseAlign) != 0) {
+  // TODO: Remove TargetBaseAlign
+  if (allowsMisaligned(SzInBytes) == 0 &&
+      (Alignment % SzInBytes) != 0 && (Alignment % TargetBaseAlign) != 0) {
     if (L0->getPointerAddressSpace() == 0) {
       // If we're loading from an object on the stack, we control its alignment,
       // so we can cheat and change it!
@@ -916,3 +921,8 @@
   NumScalarsVectorized += Chain.size();
   return true;
 }
+
+bool Vectorizer::allowsMisaligned(unsigned SzInBytes) {
+    return TTI.allowsMisalignedMemoryAccesses(SzInBytes*8);
+}
+