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 enum WasmAddressSpace : unsigned { 49 // WebAssembly uses the following address spaces: 50 // AS 0 : is the default address space for values in linear memory 51 DEFAULT = 0, 52 // AS 1 : is a non-integral address space for global variables 53 GLOBAL = 1, 54 // AS 10 : is a non-integral address space for externref values 55 EXTERNREF = 10, 56 // AS 20 : is a non-integral address space for funcref values 57 FUNCREF = 20, 58 }; 59 60 MVT getPointerTy(const DataLayout &DL, uint32_t AS = 0) const override { 61 if (AS == WasmAddressSpace::EXTERNREF) 62 return MVT::externref; 63 if (AS == WasmAddressSpace::FUNCREF) 64 return MVT::funcref; 65 return TargetLowering::getPointerTy(DL, AS); 66 } 67 MVT getPointerMemTy(const DataLayout &DL, uint32_t AS = 0) const override { 68 if (AS == WasmAddressSpace::EXTERNREF) 69 return MVT::externref; 70 if (AS == WasmAddressSpace::FUNCREF) 71 return MVT::funcref; 72 return TargetLowering::getPointerMemTy(DL, AS); 73 } 74 75 static bool isFuncrefType(const Type *Ty); 76 static bool isExternrefType(const Type *Ty); 77 78 private: 79 /// Keep a pointer to the WebAssemblySubtarget around so that we can make the 80 /// right decision when generating code for different targets. 81 const WebAssemblySubtarget *Subtarget; 82 83 AtomicExpansionKind shouldExpandAtomicRMWInIR(AtomicRMWInst *) const override; 84 bool shouldScalarizeBinop(SDValue VecOp) const override; 85 FastISel *createFastISel(FunctionLoweringInfo &FuncInfo, 86 const TargetLibraryInfo *LibInfo) const override; 87 MVT getScalarShiftAmountTy(const DataLayout &DL, EVT) const override; 88 MachineBasicBlock * 89 EmitInstrWithCustomInserter(MachineInstr &MI, 90 MachineBasicBlock *MBB) const override; 91 const char *getTargetNodeName(unsigned Opcode) const override; 92 std::pair<unsigned, const TargetRegisterClass *> 93 getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI, 94 StringRef Constraint, MVT VT) const override; 95 bool isCheapToSpeculateCttz() const override; 96 bool isCheapToSpeculateCtlz() const override; 97 bool isLegalAddressingMode(const DataLayout &DL, const AddrMode &AM, Type *Ty, 98 unsigned AS, 99 Instruction *I = nullptr) const override; 100 bool allowsMisalignedMemoryAccesses(EVT, unsigned AddrSpace, Align Alignment, 101 MachineMemOperand::Flags Flags, 102 bool *Fast) const override; 103 bool isIntDivCheap(EVT VT, AttributeList Attr) const override; 104 bool isVectorLoadExtDesirable(SDValue ExtVal) const override; 105 EVT getSetCCResultType(const DataLayout &DL, LLVMContext &Context, 106 EVT VT) const override; 107 bool getTgtMemIntrinsic(IntrinsicInfo &Info, const CallInst &I, 108 MachineFunction &MF, 109 unsigned Intrinsic) const override; 110 111 SDValue LowerCall(CallLoweringInfo &CLI, 112 SmallVectorImpl<SDValue> &InVals) const override; 113 bool CanLowerReturn(CallingConv::ID CallConv, MachineFunction &MF, 114 bool isVarArg, 115 const SmallVectorImpl<ISD::OutputArg> &Outs, 116 LLVMContext &Context) const override; 117 SDValue LowerReturn(SDValue Chain, CallingConv::ID CallConv, bool isVarArg, 118 const SmallVectorImpl<ISD::OutputArg> &Outs, 119 const SmallVectorImpl<SDValue> &OutVals, const SDLoc &dl, 120 SelectionDAG &DAG) const override; 121 SDValue LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv, 122 bool IsVarArg, 123 const SmallVectorImpl<ISD::InputArg> &Ins, 124 const SDLoc &DL, SelectionDAG &DAG, 125 SmallVectorImpl<SDValue> &InVals) const override; 126 127 void ReplaceNodeResults(SDNode *N, SmallVectorImpl<SDValue> &Results, 128 SelectionDAG &DAG) const override; 129 130 const char *getClearCacheBuiltinName() const override { 131 report_fatal_error("llvm.clear_cache is not supported on wasm"); 132 } 133 134 // Custom lowering hooks. 135 SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override; 136 SDValue LowerFrameIndex(SDValue Op, SelectionDAG &DAG) const; 137 SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const; 138 SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const; 139 SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const; 140 SDValue LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const; 141 SDValue LowerExternalSymbol(SDValue Op, SelectionDAG &DAG) const; 142 SDValue LowerBR_JT(SDValue Op, SelectionDAG &DAG) const; 143 SDValue LowerJumpTable(SDValue Op, SelectionDAG &DAG) const; 144 SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) const; 145 SDValue LowerCopyToReg(SDValue Op, SelectionDAG &DAG) const; 146 SDValue LowerIntrinsic(SDValue Op, SelectionDAG &DAG) const; 147 SDValue LowerSIGN_EXTEND_INREG(SDValue Op, SelectionDAG &DAG) const; 148 SDValue LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG) const; 149 SDValue LowerVECTOR_SHUFFLE(SDValue Op, SelectionDAG &DAG) const; 150 SDValue LowerSETCC(SDValue Op, SelectionDAG &DAG) const; 151 SDValue LowerAccessVectorElement(SDValue Op, SelectionDAG &DAG) const; 152 SDValue LowerShift(SDValue Op, SelectionDAG &DAG) const; 153 SDValue LowerFP_TO_INT_SAT(SDValue Op, SelectionDAG &DAG) const; 154 SDValue LowerLoad(SDValue Op, SelectionDAG &DAG) const; 155 SDValue LowerStore(SDValue Op, SelectionDAG &DAG) const; 156 157 // Custom DAG combine hooks 158 SDValue 159 PerformDAGCombine(SDNode *N, 160 TargetLowering::DAGCombinerInfo &DCI) const override; 161 }; 162 163 namespace WebAssembly { 164 FastISel *createFastISel(FunctionLoweringInfo &funcInfo, 165 const TargetLibraryInfo *libInfo); 166 } // end namespace WebAssembly 167 168 } // end namespace llvm 169 170 #endif 171