xref: /freebsd/contrib/llvm-project/llvm/lib/Target/WebAssembly/WebAssemblyISelLowering.h (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
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 
20 namespace llvm {
21 
22 namespace WebAssemblyISD {
23 
24 enum 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 
41 class WebAssemblySubtarget;
42 
43 class WebAssemblyTargetLowering final : public TargetLowering {
44 public:
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 
51 private:
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   EVT getSetCCResultType(const DataLayout &DL, LLVMContext &Context,
80                          EVT VT) const override;
81   bool getTgtMemIntrinsic(IntrinsicInfo &Info, const CallInst &I,
82                           MachineFunction &MF,
83                           unsigned Intrinsic) const override;
84 
85   void computeKnownBitsForTargetNode(const SDValue Op, KnownBits &Known,
86                                      const APInt &DemandedElts,
87                                      const SelectionDAG &DAG,
88                                      unsigned Depth) const override;
89 
90   TargetLoweringBase::LegalizeTypeAction
91   getPreferredVectorAction(MVT VT) const override;
92 
93   SDValue LowerCall(CallLoweringInfo &CLI,
94                     SmallVectorImpl<SDValue> &InVals) const override;
95   bool CanLowerReturn(CallingConv::ID CallConv, MachineFunction &MF,
96                       bool isVarArg,
97                       const SmallVectorImpl<ISD::OutputArg> &Outs,
98                       LLVMContext &Context) const override;
99   SDValue LowerReturn(SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
100                       const SmallVectorImpl<ISD::OutputArg> &Outs,
101                       const SmallVectorImpl<SDValue> &OutVals, const SDLoc &dl,
102                       SelectionDAG &DAG) const override;
103   SDValue LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv,
104                                bool IsVarArg,
105                                const SmallVectorImpl<ISD::InputArg> &Ins,
106                                const SDLoc &DL, SelectionDAG &DAG,
107                                SmallVectorImpl<SDValue> &InVals) const override;
108 
109   void ReplaceNodeResults(SDNode *N, SmallVectorImpl<SDValue> &Results,
110                           SelectionDAG &DAG) const override;
111 
112   const char *getClearCacheBuiltinName() const override {
113     report_fatal_error("llvm.clear_cache is not supported on wasm");
114   }
115 
116   bool
117   shouldSimplifyDemandedVectorElts(SDValue Op,
118                                    const TargetLoweringOpt &TLO) const override;
119 
120   // Custom lowering hooks.
121   SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override;
122   SDValue LowerFrameIndex(SDValue Op, SelectionDAG &DAG) const;
123   SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
124   SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
125   SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const;
126   SDValue LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const;
127   SDValue LowerExternalSymbol(SDValue Op, SelectionDAG &DAG) const;
128   SDValue LowerBR_JT(SDValue Op, SelectionDAG &DAG) const;
129   SDValue LowerJumpTable(SDValue Op, SelectionDAG &DAG) const;
130   SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) const;
131   SDValue LowerCopyToReg(SDValue Op, SelectionDAG &DAG) const;
132   SDValue LowerIntrinsic(SDValue Op, SelectionDAG &DAG) const;
133   SDValue LowerSIGN_EXTEND_INREG(SDValue Op, SelectionDAG &DAG) const;
134   SDValue LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG) const;
135   SDValue LowerVECTOR_SHUFFLE(SDValue Op, SelectionDAG &DAG) const;
136   SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG) const;
137   SDValue LowerAccessVectorElement(SDValue Op, SelectionDAG &DAG) const;
138   SDValue LowerShift(SDValue Op, SelectionDAG &DAG) const;
139   SDValue LowerFP_TO_INT_SAT(SDValue Op, SelectionDAG &DAG) const;
140   SDValue LowerLoad(SDValue Op, SelectionDAG &DAG) const;
141   SDValue LowerStore(SDValue Op, SelectionDAG &DAG) const;
142 
143   // Helper for LoadLoad and LowerStore
144   bool MatchTableForLowering(SelectionDAG &DAG, const SDLoc &DL,
145                              const SDValue &Base, GlobalAddressSDNode *&GA,
146                              SDValue &Idx) const;
147 
148   // Custom DAG combine hooks
149   SDValue
150   PerformDAGCombine(SDNode *N,
151                     TargetLowering::DAGCombinerInfo &DCI) const override;
152 };
153 
154 namespace WebAssembly {
155 FastISel *createFastISel(FunctionLoweringInfo &funcInfo,
156                          const TargetLibraryInfo *libInfo);
157 } // end namespace WebAssembly
158 
159 } // end namespace llvm
160 
161 #endif
162