1 //===-- AArch64SelectionDAGInfo.cpp - AArch64 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 AArch64SelectionDAGInfo class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "AArch64TargetMachine.h"
15 using namespace llvm;
16 
17 #define DEBUG_TYPE "aarch64-selectiondag-info"
18 
19 SDValue AArch64SelectionDAGInfo::EmitTargetCodeForMemset(
20     SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, SDValue Dst, SDValue Src,
21     SDValue Size, unsigned Align, bool isVolatile,
22     MachinePointerInfo DstPtrInfo) const {
23   // Check to see if there is a specialized entry-point for memory zeroing.
24   ConstantSDNode *V = dyn_cast<ConstantSDNode>(Src);
25   ConstantSDNode *SizeValue = dyn_cast<ConstantSDNode>(Size);
26   const AArch64Subtarget &STI =
27       DAG.getMachineFunction().getSubtarget<AArch64Subtarget>();
28   const char *bzeroEntry =
29       (V && V->isNullValue()) ? STI.getBZeroEntry() : nullptr;
30   // For small size (< 256), it is not beneficial to use bzero
31   // instead of memset.
32   if (bzeroEntry && (!SizeValue || SizeValue->getZExtValue() > 256)) {
33     const AArch64TargetLowering &TLI = *STI.getTargetLowering();
34 
35     EVT IntPtr = TLI.getPointerTy(DAG.getDataLayout());
36     Type *IntPtrTy = DAG.getDataLayout().getIntPtrType(*DAG.getContext());
37     TargetLowering::ArgListTy Args;
38     TargetLowering::ArgListEntry Entry;
39     Entry.Node = Dst;
40     Entry.Ty = IntPtrTy;
41     Args.push_back(Entry);
42     Entry.Node = Size;
43     Args.push_back(Entry);
44     TargetLowering::CallLoweringInfo CLI(DAG);
45     CLI.setDebugLoc(dl).setChain(Chain)
46       .setCallee(CallingConv::C, Type::getVoidTy(*DAG.getContext()),
47                  DAG.getExternalSymbol(bzeroEntry, IntPtr), std::move(Args))
48       .setDiscardResult();
49     std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
50     return CallResult.second;
51   }
52   return SDValue();
53 }
54 bool AArch64SelectionDAGInfo::generateFMAsInMachineCombiner(
55     CodeGenOpt::Level OptLevel) const {
56   if (OptLevel >= CodeGenOpt::Aggressive)
57     return true;
58   return false;
59 }
60