1//- WebAssemblyISelLowering.h - WebAssembly DAG Lowering Interface -*- C++ -*-//
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/// \file
10/// This file defines the interfaces that WebAssembly uses to lower LLVM
11/// code into a selection DAG.
12///
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYISELLOWERING_H
16#define LLVM_LIB_TARGET_WEBASSEMBLY_WEBASSEMBLYISELLOWERING_H
17
18#include "llvm/CodeGen/TargetLowering.h"
19
20namespace llvm {
21
22namespace WebAssemblyISD {
23
24enum NodeType : unsigned {
25  FIRST_NUMBER = ISD::BUILTIN_OP_END,
26#define HANDLE_NODETYPE(NODE) NODE,
27#define HANDLE_MEM_NODETYPE(NODE)
28#include "WebAssemblyISD.def"
29  FIRST_MEM_OPCODE = ISD::FIRST_TARGET_MEMORY_OPCODE,
30#undef HANDLE_NODETYPE
31#undef HANDLE_MEM_NODETYPE
32#define HANDLE_NODETYPE(NODE)
33#define HANDLE_MEM_NODETYPE(NODE) NODE,
34#include "WebAssemblyISD.def"
35#undef HANDLE_NODETYPE
36#undef HANDLE_MEM_NODETYPE
37};
38
39} // end namespace WebAssemblyISD
40
41class WebAssemblySubtarget;
42
43class WebAssemblyTargetLowering final : public TargetLowering {
44public:
45  WebAssemblyTargetLowering(const TargetMachine &TM,
46                            const WebAssemblySubtarget &STI);
47
48  MVT getPointerTy(const DataLayout &DL, uint32_t AS = 0) const override;
49  MVT getPointerMemTy(const DataLayout &DL, uint32_t AS = 0) const override;
50
51private:
52  /// Keep a pointer to the WebAssemblySubtarget around so that we can make the
53  /// right decision when generating code for different targets.
54  const WebAssemblySubtarget *Subtarget;
55
56  AtomicExpansionKind shouldExpandAtomicRMWInIR(AtomicRMWInst *) const override;
57  bool shouldScalarizeBinop(SDValue VecOp) const override;
58  FastISel *createFastISel(FunctionLoweringInfo &FuncInfo,
59                           const TargetLibraryInfo *LibInfo) const override;
60  MVT getScalarShiftAmountTy(const DataLayout &DL, EVT) const override;
61  MachineBasicBlock *
62  EmitInstrWithCustomInserter(MachineInstr &MI,
63                              MachineBasicBlock *MBB) const override;
64  const char *getTargetNodeName(unsigned Opcode) const override;
65  std::pair<unsigned, const TargetRegisterClass *>
66  getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
67                               StringRef Constraint, MVT VT) const override;
68  bool isCheapToSpeculateCttz(Type *Ty) const override;
69  bool isCheapToSpeculateCtlz(Type *Ty) const override;
70  bool isLegalAddressingMode(const DataLayout &DL, const AddrMode &AM, Type *Ty,
71                             unsigned AS,
72                             Instruction *I = nullptr) const override;
73  bool allowsMisalignedMemoryAccesses(EVT, unsigned AddrSpace, Align Alignment,
74                                      MachineMemOperand::Flags Flags,
75                                      unsigned *Fast) const override;
76  bool isIntDivCheap(EVT VT, AttributeList Attr) const override;
77  bool isVectorLoadExtDesirable(SDValue ExtVal) const override;
78  bool isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const override;
79  bool shouldSinkOperands(Instruction *I,
80                          SmallVectorImpl<Use *> &Ops) const override;
81  EVT getSetCCResultType(const DataLayout &DL, LLVMContext &Context,
82                         EVT VT) const override;
83  bool getTgtMemIntrinsic(IntrinsicInfo &Info, const CallInst &I,
84                          MachineFunction &MF,
85                          unsigned Intrinsic) const override;
86
87  void computeKnownBitsForTargetNode(const SDValue Op, KnownBits &Known,
88                                     const APInt &DemandedElts,
89                                     const SelectionDAG &DAG,
90                                     unsigned Depth) const override;
91
92  TargetLoweringBase::LegalizeTypeAction
93  getPreferredVectorAction(MVT VT) const override;
94
95  SDValue LowerCall(CallLoweringInfo &CLI,
96                    SmallVectorImpl<SDValue> &InVals) const override;
97  bool CanLowerReturn(CallingConv::ID CallConv, MachineFunction &MF,
98                      bool isVarArg,
99                      const SmallVectorImpl<ISD::OutputArg> &Outs,
100                      LLVMContext &Context) const override;
101  SDValue LowerReturn(SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
102                      const SmallVectorImpl<ISD::OutputArg> &Outs,
103                      const SmallVectorImpl<SDValue> &OutVals, const SDLoc &dl,
104                      SelectionDAG &DAG) const override;
105  SDValue LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv,
106                               bool IsVarArg,
107                               const SmallVectorImpl<ISD::InputArg> &Ins,
108                               const SDLoc &DL, SelectionDAG &DAG,
109                               SmallVectorImpl<SDValue> &InVals) const override;
110
111  void ReplaceNodeResults(SDNode *N, SmallVectorImpl<SDValue> &Results,
112                          SelectionDAG &DAG) const override;
113
114  const char *getClearCacheBuiltinName() const override {
115    report_fatal_error("llvm.clear_cache is not supported on wasm");
116  }
117
118  bool
119  shouldSimplifyDemandedVectorElts(SDValue Op,
120                                   const TargetLoweringOpt &TLO) const override;
121
122  // Custom lowering hooks.
123  SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override;
124  SDValue LowerFrameIndex(SDValue Op, SelectionDAG &DAG) const;
125  SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
126  SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
127  SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const;
128  SDValue LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const;
129  SDValue LowerExternalSymbol(SDValue Op, SelectionDAG &DAG) const;
130  SDValue LowerBR_JT(SDValue Op, SelectionDAG &DAG) const;
131  SDValue LowerJumpTable(SDValue Op, SelectionDAG &DAG) const;
132  SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) const;
133  SDValue LowerCopyToReg(SDValue Op, SelectionDAG &DAG) const;
134  SDValue LowerIntrinsic(SDValue Op, SelectionDAG &DAG) const;
135  SDValue LowerSIGN_EXTEND_INREG(SDValue Op, SelectionDAG &DAG) const;
136  SDValue LowerEXTEND_VECTOR_INREG(SDValue Op, SelectionDAG &DAG) const;
137  SDValue LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG) const;
138  SDValue LowerVECTOR_SHUFFLE(SDValue Op, SelectionDAG &DAG) const;
139  SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG) const;
140  SDValue LowerAccessVectorElement(SDValue Op, SelectionDAG &DAG) const;
141  SDValue LowerShift(SDValue Op, SelectionDAG &DAG) const;
142  SDValue LowerFP_TO_INT_SAT(SDValue Op, SelectionDAG &DAG) const;
143  SDValue LowerLoad(SDValue Op, SelectionDAG &DAG) const;
144  SDValue LowerStore(SDValue Op, SelectionDAG &DAG) const;
145
146  // Custom DAG combine hooks
147  SDValue
148  PerformDAGCombine(SDNode *N,
149                    TargetLowering::DAGCombinerInfo &DCI) const override;
150};
151
152namespace WebAssembly {
153FastISel *createFastISel(FunctionLoweringInfo &funcInfo,
154                         const TargetLibraryInfo *libInfo);
155} // end namespace WebAssembly
156
157} // end namespace llvm
158
159#endif
160