Allow vectorization of division by uniform power of 2.

This patch adds support to recognize division by uniform power of 2 and modifies the cost table to vectorize division by uniform power of 2 whenever possible.
Updates Cost model for Loop and SLP Vectorizer.The cost table is currently only updated for X86 backend.
Thanks to Hal, Andrea, Sanjay for the review. (http://reviews.llvm.org/D4971)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216371 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/BasicTargetTransformInfo.cpp

@@ -104,7 +104,8 @@ public:
   unsigned getMaximumUnrollFactor() const override;
   unsigned getRegisterBitWidth(bool Vector) const override;
   unsigned getArithmeticInstrCost(unsigned Opcode, Type *Ty, OperandValueKind,
-                                  OperandValueKind) const override;
+                                  OperandValueKind, OperandValueProperties,
+                                  OperandValueProperties) const override;
   unsigned getShuffleCost(ShuffleKind Kind, Type *Tp,
                           int Index, Type *SubTp) const override;
   unsigned getCastInstrCost(unsigned Opcode, Type *Dst,
@@ -289,8 +290,9 @@ unsigned BasicTTI::getMaximumUnrollFactor() const {
 }
 
 unsigned BasicTTI::getArithmeticInstrCost(unsigned Opcode, Type *Ty,
-                                          OperandValueKind,
-                                          OperandValueKind) const {
+                                          OperandValueKind, OperandValueKind,
+                                          OperandValueProperties,
+                                          OperandValueProperties) const {
   // Check if any of the operands are vector operands.
   const TargetLoweringBase *TLI = getTLI();
   int ISD = TLI->InstructionOpcodeToISD(Opcode);