llvm-project/llvm/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp

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2.3 KiB
C++

//===-- AArch64SelectionDAGInfo.cpp - AArch64 SelectionDAG Info -----------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements the AArch64SelectionDAGInfo class.
//
//===----------------------------------------------------------------------===//
#include "AArch64TargetMachine.h"
using namespace llvm;
#define DEBUG_TYPE "aarch64-selectiondag-info"
SDValue AArch64SelectionDAGInfo::EmitTargetCodeForMemset(
SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, SDValue Dst, SDValue Src,
SDValue Size, unsigned Align, bool isVolatile,
MachinePointerInfo DstPtrInfo) const {
// Check to see if there is a specialized entry-point for memory zeroing.
ConstantSDNode *V = dyn_cast<ConstantSDNode>(Src);
ConstantSDNode *SizeValue = dyn_cast<ConstantSDNode>(Size);
const AArch64Subtarget &STI =
DAG.getMachineFunction().getSubtarget<AArch64Subtarget>();
const char *bzeroName = (V && V->isNullValue())
? DAG.getTargetLoweringInfo().getLibcallName(RTLIB::BZERO) : nullptr;
// For small size (< 256), it is not beneficial to use bzero
// instead of memset.
if (bzeroName && (!SizeValue || SizeValue->getZExtValue() > 256)) {
const AArch64TargetLowering &TLI = *STI.getTargetLowering();
EVT IntPtr = TLI.getPointerTy(DAG.getDataLayout());
Type *IntPtrTy = DAG.getDataLayout().getIntPtrType(*DAG.getContext());
TargetLowering::ArgListTy Args;
TargetLowering::ArgListEntry Entry;
Entry.Node = Dst;
Entry.Ty = IntPtrTy;
Args.push_back(Entry);
Entry.Node = Size;
Args.push_back(Entry);
TargetLowering::CallLoweringInfo CLI(DAG);
CLI.setDebugLoc(dl)
.setChain(Chain)
.setLibCallee(CallingConv::C, Type::getVoidTy(*DAG.getContext()),
DAG.getExternalSymbol(bzeroName, IntPtr),
std::move(Args))
.setDiscardResult();
std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
return CallResult.second;
}
return SDValue();
}
bool AArch64SelectionDAGInfo::generateFMAsInMachineCombiner(
CodeGenOpt::Level OptLevel) const {
return OptLevel >= CodeGenOpt::Aggressive;
}