Inline memset when there is a constant value and count.

src/IceTargetLoweringX86Base.h

Index: src/IceTargetLoweringX86Base.h
diff --git a/src/IceTargetLoweringX86Base.h b/src/IceTargetLoweringX86Base.h
index 58de7217571b44e0d0898e176380e9962326a54b..b53b4214f24943d04e3c52cec88c18bc774653d8 100644
--- a/src/IceTargetLoweringX86Base.h
+++ b/src/IceTargetLoweringX86Base.h
@@ -160,6 +160,8 @@ protected:
                       Operand *Val);
   void lowerCountZeros(bool Cttz, Type Ty, Variable *Dest, Operand *FirstVal,
                        Operand *SecondVal);
+  /// Replace a function call with inline instructions.
+  void lowerMemset(Operand *Dest, Operand *Val, Operand *Count);
 
   /// Check the comparison is in [Min,Max]. The flags register will be modified
   /// with:
@@ -214,7 +216,8 @@ protected:
 
   Variable *copyToReg(Operand *Src, int32_t RegNum = Variable::NoRegister);
 
-  /// Returns a vector in a register with the given constant entries.
+  /// \name Returns a vector in a register with the given constant entries.
+  /// @{
   Variable *makeVectorOfZeros(Type Ty, int32_t RegNum = Variable::NoRegister);
   Variable *makeVectorOfOnes(Type Ty, int32_t RegNum = Variable::NoRegister);
   Variable *makeVectorOfMinusOnes(Type Ty,
@@ -223,6 +226,7 @@ protected:
                                       int32_t RegNum = Variable::NoRegister);
   Variable *makeVectorOfFabsMask(Type Ty,
                                  int32_t RegNum = Variable::NoRegister);
+  /// @}
 
   /// Return a memory operand corresponding to a stack allocated Variable.
   typename Traits::X86OperandMem *