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 DataLayout &DL)
  20     : TargetSelectionDAGInfo(&DL) {}
  21
  22 XCoreSelectionDAGInfo::~XCoreSelectionDAGInfo() {
  23 }
  24
  25 SDValue XCoreSelectionDAGInfo::
  26 EmitTargetCodeForMemcpy(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 =
  37         *DAG.getTarget().getSubtargetImpl()->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 CLI(DAG);
  46     CLI.setDebugLoc(dl).setChain(Chain)
  47       .setCallee(TLI.getLibcallCallingConv(RTLIB::MEMCPY),
  48                  Type::getVoidTy(*DAG.getContext()),
  49                  DAG.getExternalSymbol("__memcpy_4", TLI.getPointerTy()),
  50                  std::move(Args), 0)
  51       .setDiscardResult();
  52
  53     std::pair<SDValue,SDValue> CallResult = TLI.LowerCallTo(CLI);
  54     return CallResult.second;
  55   }
  56
  57   // Otherwise have the target-independent code call memcpy.
  58   return SDValue();
  59 }