Inline memove for small constant sizes and refactor memcpy and memset.

src/IceTargetLoweringX86Base.h

 //===- subzero/src/IceTargetLoweringX86Base.h - x86 lowering ----*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 174 matching lines @@
   /// Naive lowering of cmpxchg.
   void lowerAtomicCmpxchg(Variable *DestPrev, Operand *Ptr, Operand *Expected,
                           Operand *Desired);
   /// Attempt a more optimized lowering of cmpxchg. Returns true if optimized.
   bool tryOptimizedCmpxchgCmpBr(Variable *DestPrev, Operand *Ptr,
                                 Operand *Expected, Operand *Desired);
   void lowerAtomicRMW(Variable *Dest, uint32_t Operation, Operand *Ptr,
                       Operand *Val);
   void lowerCountZeros(bool Cttz, Type Ty, Variable *Dest, Operand *FirstVal,
                        Operand *SecondVal);
-  /// Replace a call to memcpy with inline instructions.
+  /// Load from memory for a given type.
+  void typedLoad(Type Ty, Variable *Dest, Variable *Base, Constant *Offset);
+  /// Store to memory for a given type.
+  void typedStore(Type Ty, Variable *Value, Variable *Base, Constant *Offset);
+  /// Copy memory of given type from Src to Dest using OffsetAmt on both.
+  void copyMemory(Type Ty, Variable *Dest, Variable *Src, int32_t OffsetAmt);
+  /// Replace some calls to memcpy with inline instructions.
   void lowerMemcpy(Operand *Dest, Operand *Src, Operand *Count);
-  /// Replace a call to memset with inline instructions.
+  /// Replace some calls to memmove with inline instructions.
+  void lowerMemmove(Operand *Dest, Operand *Src, Operand *Count);
+  /// Replace some calls to memset with inline instructions.
   void lowerMemset(Operand *Dest, Operand *Val, Operand *Count);
 
   /// Lower an indirect jump adding sandboxing when needed.
   void lowerIndirectJump(Variable *Target);
 
   /// Check the comparison is in [Min,Max]. The flags register will be modified
   /// with:
   ///   - below equal, if in range
   ///   - above, set if not in range
   /// The index into the range is returned.
@@ skipping 36 matching lines @@
   Operand *legalizeSrc0ForCmp(Operand *Src0, Operand *Src1);
   /// Turn a pointer operand into a memory operand that can be
   /// used by a real load/store operation. Legalizes the operand as well.
   /// This is a nop if the operand is already a legal memory operand.
   typename Traits::X86OperandMem *formMemoryOperand(Operand *Ptr, Type Ty,
                                                     bool DoLegalize = true);
 
   Variable *makeReg(Type Ty, int32_t RegNum = Variable::NoRegister);
   static Type stackSlotType();
 
+  static constexpr uint32_t NoSizeLimit = 0;
+  static const Type TypeForSize[];
+  /// Returns the largest type which is equal to or larger than Size bytes. The
+  /// type is suitable for copying memory i.e. a load and store will be a
+  /// single instruction (for example x86 will get f64 not i64).
+  static Type largestTypeInSize(uint32_t Size, uint32_t MaxSize = NoSizeLimit);
+  /// Returns the smallest type which is equal to or larger than Size bytes. If
+  /// one doesn't exist then the largest type smaller than Size bytes is
+  /// returned. The type is suitable for memory copies as described at
+  /// largestTypeInSize.
+  static Type firstTypeThatFitsSize(uint32_t Size,
+                                    uint32_t MaxSize = NoSizeLimit);
+
   Variable *copyToReg(Operand *Src, int32_t RegNum = Variable::NoRegister);
 
   /// \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,
                                   int32_t RegNum = Variable::NoRegister);
   Variable *makeVectorOfHighOrderBits(Type Ty,
                                       int32_t RegNum = Variable::NoRegister);
@@ skipping 430 matching lines @@
   }
 
   BoolFolding FoldingInfo;
 };
 } // end of namespace X86Internal
 } // end of namespace Ice
 
 #include "IceTargetLoweringX86BaseImpl.h"
 
 #endif // SUBZERO_SRC_ICETARGETLOWERINGX86BASE_H