43 lines
1.6 KiB
C++
43 lines
1.6 KiB
C++
|
//===-- BPFSelectionDAGInfo.cpp - BPF 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 BPFSelectionDAGInfo class.
|
||
|
|
//
|
||
|
|
//===----------------------------------------------------------------------===//
|
||
|
|
|
||
|
|
#include "BPFTargetMachine.h"
|
||
|
|
#include "llvm/CodeGen/SelectionDAG.h"
|
||
|
|
#include "llvm/IR/DerivedTypes.h"
|
||
|
|
using namespace llvm;
|
||
|
|
|
||
|
|
#define DEBUG_TYPE "bpf-selectiondag-info"
|
||
|
|
|
||
|
|
SDValue BPFSelectionDAGInfo::EmitTargetCodeForMemcpy(
|
||
|
|
SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, SDValue Dst, SDValue Src,
|
||
|
|
SDValue Size, Align Alignment, bool isVolatile, bool AlwaysInline,
|
||
|
|
MachinePointerInfo DstPtrInfo, MachinePointerInfo SrcPtrInfo) const {
|
||
|
|
// Requires the copy size to be a constant.
|
||
|
|
ConstantSDNode *ConstantSize = dyn_cast<ConstantSDNode>(Size);
|
||
|
|
if (!ConstantSize)
|
||
|
|
return SDValue();
|
||
|
|
|
||
|
|
unsigned CopyLen = ConstantSize->getZExtValue();
|
||
|
|
unsigned StoresNumEstimate = alignTo(CopyLen, Alignment) >> Log2(Alignment);
|
||
|
|
// Impose the same copy length limit as MaxStoresPerMemcpy.
|
||
|
|
if (StoresNumEstimate > getCommonMaxStoresPerMemFunc())
|
||
|
|
return SDValue();
|
||
|
|
|
||
|
|
SDVTList VTs = DAG.getVTList(MVT::Other, MVT::Glue);
|
||
|
|
|
||
|
|
Dst = DAG.getNode(BPFISD::MEMCPY, dl, VTs, Chain, Dst, Src,
|
||
|
|
DAG.getConstant(CopyLen, dl, MVT::i64),
|
||
|
|
DAG.getConstant(Alignment.value(), dl, MVT::i64));
|
||
|
|
|
||
|
|
return Dst.getValue(0);
|
||
|
|
}
|