XCoreSelectionDAGInfo.cpp revision 36b56886974eae4f9c5ebc96befd3e7bfe5de338 
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#define DEBUG_TYPE "xcore-selectiondag-info"
15#include "XCoreTargetMachine.h"
16using namespace llvm;
17
18XCoreSelectionDAGInfo::XCoreSelectionDAGInfo(const XCoreTargetMachine &TM)
19  : TargetSelectionDAGInfo(TM) {
20}
21
22XCoreSelectionDAGInfo::~XCoreSelectionDAGInfo() {
23}
24
25SDValue XCoreSelectionDAGInfo::
26EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc dl, SDValue Chain,
27                        SDValue Dst, SDValue Src, SDValue Size, unsigned Align,
28                        bool isVolatile, bool AlwaysInline,
29                        MachinePointerInfo DstPtrInfo,
30                        MachinePointerInfo SrcPtrInfo) const
31{
32  unsigned SizeBitWidth = Size.getValueType().getSizeInBits();
33  // Call __memcpy_4 if the src, dst and size are all 4 byte aligned.
34  if (!AlwaysInline && (Align & 3) == 0 &&
35      DAG.MaskedValueIsZero(Size, APInt(SizeBitWidth, 3))) {
36    const TargetLowering &TLI = *DAG.getTarget().getTargetLowering();
37    TargetLowering::ArgListTy Args;
38    TargetLowering::ArgListEntry Entry;
39    Entry.Ty = TLI.getDataLayout()->getIntPtrType(*DAG.getContext());
40    Entry.Node = Dst; Args.push_back(Entry);
41    Entry.Node = Src; Args.push_back(Entry);
42    Entry.Node = Size; Args.push_back(Entry);
43
44    TargetLowering::CallLoweringInfo
45    CLI(Chain, Type::getVoidTy(*DAG.getContext()), false, false, false, false,
46        0, TLI.getLibcallCallingConv(RTLIB::MEMCPY), /*isTailCall=*/false,
47        /*doesNotRet=*/false, /*isReturnValueUsed=*/false,
48        DAG.getExternalSymbol("__memcpy_4", TLI.getPointerTy()), Args, DAG, dl);
49    std::pair<SDValue,SDValue> CallResult =
50      TLI.LowerCallTo(CLI);
51    return CallResult.second;
52  }
53
54  // Otherwise have the target-independent code call memcpy.
55  return SDValue();
56}
57