lib/Target/XCore/XCoreSelectionDAGInfo.cpp

   1 //===-- XCoreSelectionDAGInfo.cpp - XCore SelectionDAG Info ---------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the XCoreSelectionDAGInfo class.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "XCoreTargetMachine.h"
  15 using namespace llvm;
  16
  17 #define DEBUG_TYPE "xcore-selectiondag-info"
  18
  19 XCoreSelectionDAGInfo::XCoreSelectionDAGInfo(const XCoreTargetMachine &TM)
  20   : TargetSelectionDAGInfo(TM) {
  21 }
  22
  23 XCoreSelectionDAGInfo::~XCoreSelectionDAGInfo() {
  24 }
  25
  26 SDValue XCoreSelectionDAGInfo::
  27 EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc dl, SDValue Chain,
  28                         SDValue Dst, SDValue Src, SDValue Size, unsigned Align,
  29                         bool isVolatile, bool AlwaysInline,
  30                         MachinePointerInfo DstPtrInfo,
  31                         MachinePointerInfo SrcPtrInfo) const
  32 {
  33   unsigned SizeBitWidth = Size.getValueType().getSizeInBits();
  34   // Call __memcpy_4 if the src, dst and size are all 4 byte aligned.
  35   if (!AlwaysInline && (Align & 3) == 0 &&
  36       DAG.MaskedValueIsZero(Size, APInt(SizeBitWidth, 3))) {
  37     const TargetLowering &TLI = *DAG.getTarget().getTargetLowering();
  38     TargetLowering::ArgListTy Args;
  39     TargetLowering::ArgListEntry Entry;
  40     Entry.Ty = TLI.getDataLayout()->getIntPtrType(*DAG.getContext());
  41     Entry.Node = Dst; Args.push_back(Entry);
  42     Entry.Node = Src; Args.push_back(Entry);
  43     Entry.Node = Size; Args.push_back(Entry);
  44
  45     TargetLowering::CallLoweringInfo
  46     CLI(Chain, Type::getVoidTy(*DAG.getContext()), false, false, false, false,
  47         0, TLI.getLibcallCallingConv(RTLIB::MEMCPY), /*isTailCall=*/false,
  48         /*doesNotRet=*/false, /*isReturnValueUsed=*/false,
  49         DAG.getExternalSymbol("__memcpy_4", TLI.getPointerTy()), Args, DAG, dl);
  50     std::pair<SDValue,SDValue> CallResult =
  51       TLI.LowerCallTo(CLI);
  52     return CallResult.second;
  53   }
  54
  55   // Otherwise have the target-independent code call memcpy.
  56   return SDValue();
  57 }