1//===-- HexagonSelectionDAGInfo.cpp - Hexagon SelectionDAG Info -----------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements the HexagonSelectionDAGInfo class.
10//
11//===----------------------------------------------------------------------===//
12
13#include "HexagonTargetMachine.h"
14#include "llvm/CodeGen/SelectionDAG.h"
15using namespace llvm;
16
17#define DEBUG_TYPE "hexagon-selectiondag-info"
18
19SDValue HexagonSelectionDAGInfo::EmitTargetCodeForMemcpy(
20 SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, SDValue Dst, SDValue Src,
21 SDValue Size, Align Alignment, bool isVolatile, bool AlwaysInline,
22 MachinePointerInfo DstPtrInfo, MachinePointerInfo SrcPtrInfo) const {
23 ConstantSDNode *ConstantSize = dyn_cast<ConstantSDNode>(Val&: Size);
24 if (AlwaysInline || Alignment < Align(4) || !ConstantSize)
25 return SDValue();
26
27 uint64_t SizeVal = ConstantSize->getZExtValue();
28 if (SizeVal < 32 || (SizeVal % 8) != 0)
29 return SDValue();
30
31 // Special case aligned memcpys with size >= 32 bytes and a multiple of 8.
32 //
33 const TargetLowering &TLI = *DAG.getSubtarget().getTargetLowering();
34 TargetLowering::ArgListTy Args;
35 TargetLowering::ArgListEntry Entry;
36 Entry.Ty = DAG.getDataLayout().getIntPtrType(C&: *DAG.getContext());
37 Entry.Node = Dst;
38 Args.push_back(x: Entry);
39 Entry.Node = Src;
40 Args.push_back(x: Entry);
41 Entry.Node = Size;
42 Args.push_back(x: Entry);
43
44 const char *SpecialMemcpyName = TLI.getLibcallName(
45 Call: RTLIB::HEXAGON_MEMCPY_LIKELY_ALIGNED_MIN32BYTES_MULT8BYTES);
46 const MachineFunction &MF = DAG.getMachineFunction();
47 bool LongCalls = MF.getSubtarget<HexagonSubtarget>().useLongCalls();
48 unsigned Flags = LongCalls ? HexagonII::HMOTF_ConstExtended : 0;
49
50 CallingConv::ID CC = TLI.getLibcallCallingConv(
51 Call: RTLIB::HEXAGON_MEMCPY_LIKELY_ALIGNED_MIN32BYTES_MULT8BYTES);
52
53 TargetLowering::CallLoweringInfo CLI(DAG);
54 CLI.setDebugLoc(dl)
55 .setChain(Chain)
56 .setLibCallee(
57 CC, ResultType: Type::getVoidTy(C&: *DAG.getContext()),
58 Target: DAG.getTargetExternalSymbol(
59 Sym: SpecialMemcpyName, VT: TLI.getPointerTy(DL: DAG.getDataLayout()), TargetFlags: Flags),
60 ArgsList: std::move(Args))
61 .setDiscardResult();
62
63 std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
64 return CallResult.second;
65}
66