| 1 | //===-- BPFSelectionDAGInfo.cpp - BPF SelectionDAG Info -------------------===// |
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| 2 | // |
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| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
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| 4 | // See https://llvm.org/LICENSE.txt for license information. |
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| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
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| 6 | // |
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| 7 | //===----------------------------------------------------------------------===// |
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| 8 | // |
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| 9 | // This file implements the BPFSelectionDAGInfo class. |
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| 10 | // |
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| 11 | //===----------------------------------------------------------------------===// |
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| 12 | |
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| 13 | #include "BPFTargetMachine.h" |
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| 14 | #include "llvm/CodeGen/SelectionDAG.h" |
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| 15 | #include "llvm/IR/DerivedTypes.h" |
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| 16 | using namespace llvm; |
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| 17 | |
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| 18 | #define DEBUG_TYPE "bpf-selectiondag-info" |
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| 19 | |
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| 20 | SDValue BPFSelectionDAGInfo::EmitTargetCodeForMemcpy( |
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| 21 | SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, SDValue Dst, SDValue Src, |
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| 22 | SDValue Size, Align Alignment, bool isVolatile, bool AlwaysInline, |
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| 23 | MachinePointerInfo DstPtrInfo, MachinePointerInfo SrcPtrInfo) const { |
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| 24 | // Requires the copy size to be a constant. |
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| 25 | ConstantSDNode *ConstantSize = dyn_cast<ConstantSDNode>(Val&: Size); |
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| 26 | if (!ConstantSize) |
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| 27 | return SDValue(); |
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| 28 | |
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| 29 | unsigned CopyLen = ConstantSize->getZExtValue(); |
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| 30 | unsigned StoresNumEstimate = alignTo(Size: CopyLen, A: Alignment) >> Log2(A: Alignment); |
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| 31 | // Impose the same copy length limit as MaxStoresPerMemcpy. |
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| 32 | if (StoresNumEstimate > getCommonMaxStoresPerMemFunc()) |
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| 33 | return SDValue(); |
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| 34 | |
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| 35 | SDVTList VTs = DAG.getVTList(MVT::Other, MVT::Glue); |
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| 36 | |
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| 37 | Dst = DAG.getNode(BPFISD::MEMCPY, dl, VTs, Chain, Dst, Src, |
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| 38 | DAG.getConstant(CopyLen, dl, MVT::i64), |
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| 39 | DAG.getConstant(Alignment.value(), dl, MVT::i64)); |
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| 40 | |
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| 41 | return Dst.getValue(R: 0); |
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| 42 | } |
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| 43 | |
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