Index: llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h
===================================================================
--- llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h
+++ llvm/trunk/include/llvm/Analysis/TargetTransformInfo.h
@@ -670,6 +670,14 @@
   /// \return The width of the smallest vector register type.
   unsigned getMinVectorRegisterBitWidth() const;
 
+  /// \return True if the vectorization factor should be chosen to
+  /// make the vector of the smallest element type match the size of a
+  /// vector register. For wider element types, this could result in
+  /// creating vectors that span multiple vector registers.
+  /// If false, the vectorization factor will be chosen based on the
+  /// size of the widest element type.
+  bool shouldMaximizeVectorBandwidth(bool OptSize) const;
+
   /// \return True if it should be considered for address type promotion.
   /// \p AllowPromotionWithoutCommonHeader Set true if promoting \p I is
   /// profitable without finding other extensions fed by the same input.
@@ -1062,6 +1070,7 @@
   virtual unsigned getNumberOfRegisters(bool Vector) = 0;
   virtual unsigned getRegisterBitWidth(bool Vector) const = 0;
   virtual unsigned getMinVectorRegisterBitWidth() = 0;
+  virtual bool shouldMaximizeVectorBandwidth(bool OptSize) const = 0;
   virtual bool shouldConsiderAddressTypePromotion(
       const Instruction &I, bool &AllowPromotionWithoutCommonHeader) = 0;
   virtual unsigned getCacheLineSize() = 0;
@@ -1357,6 +1366,9 @@
   unsigned getMinVectorRegisterBitWidth() override {
     return Impl.getMinVectorRegisterBitWidth();
   }
+  bool shouldMaximizeVectorBandwidth(bool OptSize) const override {
+    return Impl.shouldMaximizeVectorBandwidth(OptSize);
+  }
   bool shouldConsiderAddressTypePromotion(
       const Instruction &I, bool &AllowPromotionWithoutCommonHeader) override {
     return Impl.shouldConsiderAddressTypePromotion(
Index: llvm/trunk/include/llvm/Analysis/TargetTransformInfoImpl.h
===================================================================
--- llvm/trunk/include/llvm/Analysis/TargetTransformInfoImpl.h
+++ llvm/trunk/include/llvm/Analysis/TargetTransformInfoImpl.h
@@ -349,6 +349,8 @@
 
   unsigned getMinVectorRegisterBitWidth() { return 128; }
 
+  bool shouldMaximizeVectorBandwidth(bool OptSize) const { return false; }
+
   bool
   shouldConsiderAddressTypePromotion(const Instruction &I,
                                      bool &AllowPromotionWithoutCommonHeader) {
Index: llvm/trunk/lib/Analysis/TargetTransformInfo.cpp
===================================================================
--- llvm/trunk/lib/Analysis/TargetTransformInfo.cpp
+++ llvm/trunk/lib/Analysis/TargetTransformInfo.cpp
@@ -338,6 +338,10 @@
   return TTIImpl->getMinVectorRegisterBitWidth();
 }
 
+bool TargetTransformInfo::shouldMaximizeVectorBandwidth(bool OptSize) const {
+  return TTIImpl->shouldMaximizeVectorBandwidth(OptSize);
+}
+
 bool TargetTransformInfo::shouldConsiderAddressTypePromotion(
     const Instruction &I, bool &AllowPromotionWithoutCommonHeader) const {
   return TTIImpl->shouldConsiderAddressTypePromotion(
Index: llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp
===================================================================
--- llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ llvm/trunk/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -6139,7 +6139,8 @@
   }
 
   unsigned MaxVF = MaxVectorSize;
-  if (MaximizeBandwidth && !OptForSize) {
+  if (TTI.shouldMaximizeVectorBandwidth(OptForSize) ||
+      (MaximizeBandwidth && !OptForSize)) {
     // Collect all viable vectorization factors larger than the default MaxVF
     // (i.e. MaxVectorSize).
     SmallVector<unsigned, 8> VFs;