|  | //===- ARMISelLowering.h - ARM DAG Lowering Interface -----------*- C++ -*-===// | 
|  | // | 
|  | // 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 defines the interfaces that ARM uses to lower LLVM code into a | 
|  | // selection DAG. | 
|  | // | 
|  | //===----------------------------------------------------------------------===// | 
|  |  | 
|  | #ifndef LLVM_LIB_TARGET_ARM_ARMISELLOWERING_H | 
|  | #define LLVM_LIB_TARGET_ARM_ARMISELLOWERING_H | 
|  |  | 
|  | #include "MCTargetDesc/ARMBaseInfo.h" | 
|  | #include "llvm/ADT/SmallVector.h" | 
|  | #include "llvm/ADT/StringRef.h" | 
|  | #include "llvm/CodeGen/CallingConvLower.h" | 
|  | #include "llvm/CodeGen/ISDOpcodes.h" | 
|  | #include "llvm/CodeGen/MachineFunction.h" | 
|  | #include "llvm/CodeGen/SelectionDAGNodes.h" | 
|  | #include "llvm/CodeGen/TargetLowering.h" | 
|  | #include "llvm/CodeGen/ValueTypes.h" | 
|  | #include "llvm/IR/Attributes.h" | 
|  | #include "llvm/IR/CallingConv.h" | 
|  | #include "llvm/IR/Function.h" | 
|  | #include "llvm/IR/IRBuilder.h" | 
|  | #include "llvm/IR/InlineAsm.h" | 
|  | #include "llvm/Support/CodeGen.h" | 
|  | #include "llvm/Support/MachineValueType.h" | 
|  | #include <utility> | 
|  |  | 
|  | namespace llvm { | 
|  |  | 
|  | class ARMSubtarget; | 
|  | class DataLayout; | 
|  | class FastISel; | 
|  | class FunctionLoweringInfo; | 
|  | class GlobalValue; | 
|  | class InstrItineraryData; | 
|  | class Instruction; | 
|  | class MachineBasicBlock; | 
|  | class MachineInstr; | 
|  | class SelectionDAG; | 
|  | class TargetLibraryInfo; | 
|  | class TargetMachine; | 
|  | class TargetRegisterInfo; | 
|  | class VectorType; | 
|  |  | 
|  | namespace ARMISD { | 
|  |  | 
|  | // ARM Specific DAG Nodes | 
|  | enum NodeType : unsigned { | 
|  | // Start the numbering where the builtin ops and target ops leave off. | 
|  | FIRST_NUMBER = ISD::BUILTIN_OP_END, | 
|  |  | 
|  | Wrapper,      // Wrapper - A wrapper node for TargetConstantPool, | 
|  | // TargetExternalSymbol, and TargetGlobalAddress. | 
|  | WrapperPIC,   // WrapperPIC - A wrapper node for TargetGlobalAddress in | 
|  | // PIC mode. | 
|  | WrapperJT,    // WrapperJT - A wrapper node for TargetJumpTable | 
|  |  | 
|  | // Add pseudo op to model memcpy for struct byval. | 
|  | COPY_STRUCT_BYVAL, | 
|  |  | 
|  | CALL,         // Function call. | 
|  | CALL_PRED,    // Function call that's predicable. | 
|  | CALL_NOLINK,  // Function call with branch not branch-and-link. | 
|  | BRCOND,       // Conditional branch. | 
|  | BR_JT,        // Jumptable branch. | 
|  | BR2_JT,       // Jumptable branch (2 level - jumptable entry is a jump). | 
|  | RET_FLAG,     // Return with a flag operand. | 
|  | INTRET_FLAG,  // Interrupt return with an LR-offset and a flag operand. | 
|  |  | 
|  | PIC_ADD,      // Add with a PC operand and a PIC label. | 
|  |  | 
|  | ASRL,         // MVE long arithmetic shift right. | 
|  | LSRL,         // MVE long shift right. | 
|  | LSLL,         // MVE long shift left. | 
|  |  | 
|  | CMP,          // ARM compare instructions. | 
|  | CMN,          // ARM CMN instructions. | 
|  | CMPZ,         // ARM compare that sets only Z flag. | 
|  | CMPFP,        // ARM VFP compare instruction, sets FPSCR. | 
|  | CMPFPw0,      // ARM VFP compare against zero instruction, sets FPSCR. | 
|  | FMSTAT,       // ARM fmstat instruction. | 
|  |  | 
|  | CMOV,         // ARM conditional move instructions. | 
|  | SUBS,         // Flag-setting subtraction. | 
|  |  | 
|  | SSAT,         // Signed saturation | 
|  | USAT,         // Unsigned saturation | 
|  |  | 
|  | BCC_i64, | 
|  |  | 
|  | SRL_FLAG,     // V,Flag = srl_flag X -> srl X, 1 + save carry out. | 
|  | SRA_FLAG,     // V,Flag = sra_flag X -> sra X, 1 + save carry out. | 
|  | RRX,          // V = RRX X, Flag     -> srl X, 1 + shift in carry flag. | 
|  |  | 
|  | ADDC,         // Add with carry | 
|  | ADDE,         // Add using carry | 
|  | SUBC,         // Sub with carry | 
|  | SUBE,         // Sub using carry | 
|  | LSLS,         // Shift left producing carry | 
|  |  | 
|  | VMOVRRD,      // double to two gprs. | 
|  | VMOVDRR,      // Two gprs to double. | 
|  | VMOVSR,       // move gpr to single, used for f32 literal constructed in a gpr | 
|  |  | 
|  | EH_SJLJ_SETJMP,         // SjLj exception handling setjmp. | 
|  | EH_SJLJ_LONGJMP,        // SjLj exception handling longjmp. | 
|  | EH_SJLJ_SETUP_DISPATCH, // SjLj exception handling setup_dispatch. | 
|  |  | 
|  | TC_RETURN,    // Tail call return pseudo. | 
|  |  | 
|  | THREAD_POINTER, | 
|  |  | 
|  | DYN_ALLOC,    // Dynamic allocation on the stack. | 
|  |  | 
|  | MEMBARRIER_MCR, // Memory barrier (MCR) | 
|  |  | 
|  | PRELOAD,      // Preload | 
|  |  | 
|  | WIN__CHKSTK,  // Windows' __chkstk call to do stack probing. | 
|  | WIN__DBZCHK,  // Windows' divide by zero check | 
|  |  | 
|  | WLS,          // Low-overhead loops, While Loop Start | 
|  | LOOP_DEC,     // Really a part of LE, performs the sub | 
|  | LE,           // Low-overhead loops, Loop End | 
|  |  | 
|  | PREDICATE_CAST, // Predicate cast for MVE i1 types | 
|  |  | 
|  | VCMP,         // Vector compare. | 
|  | VCMPZ,        // Vector compare to zero. | 
|  | VTST,         // Vector test bits. | 
|  |  | 
|  | // Vector shift by vector | 
|  | VSHLs,        // ...left/right by signed | 
|  | VSHLu,        // ...left/right by unsigned | 
|  |  | 
|  | // Vector shift by immediate: | 
|  | VSHLIMM,      // ...left | 
|  | VSHRsIMM,     // ...right (signed) | 
|  | VSHRuIMM,     // ...right (unsigned) | 
|  |  | 
|  | // Vector rounding shift by immediate: | 
|  | VRSHRsIMM,    // ...right (signed) | 
|  | VRSHRuIMM,    // ...right (unsigned) | 
|  | VRSHRNIMM,    // ...right narrow | 
|  |  | 
|  | // Vector saturating shift by immediate: | 
|  | VQSHLsIMM,    // ...left (signed) | 
|  | VQSHLuIMM,    // ...left (unsigned) | 
|  | VQSHLsuIMM,   // ...left (signed to unsigned) | 
|  | VQSHRNsIMM,   // ...right narrow (signed) | 
|  | VQSHRNuIMM,   // ...right narrow (unsigned) | 
|  | VQSHRNsuIMM,  // ...right narrow (signed to unsigned) | 
|  |  | 
|  | // Vector saturating rounding shift by immediate: | 
|  | VQRSHRNsIMM,  // ...right narrow (signed) | 
|  | VQRSHRNuIMM,  // ...right narrow (unsigned) | 
|  | VQRSHRNsuIMM, // ...right narrow (signed to unsigned) | 
|  |  | 
|  | // Vector shift and insert: | 
|  | VSLIIMM,      // ...left | 
|  | VSRIIMM,      // ...right | 
|  |  | 
|  | // Vector get lane (VMOV scalar to ARM core register) | 
|  | // (These are used for 8- and 16-bit element types only.) | 
|  | VGETLANEu,    // zero-extend vector extract element | 
|  | VGETLANEs,    // sign-extend vector extract element | 
|  |  | 
|  | // Vector move immediate and move negated immediate: | 
|  | VMOVIMM, | 
|  | VMVNIMM, | 
|  |  | 
|  | // Vector move f32 immediate: | 
|  | VMOVFPIMM, | 
|  |  | 
|  | // Move H <-> R, clearing top 16 bits | 
|  | VMOVrh, | 
|  | VMOVhr, | 
|  |  | 
|  | // Vector duplicate: | 
|  | VDUP, | 
|  | VDUPLANE, | 
|  |  | 
|  | // Vector shuffles: | 
|  | VEXT,         // extract | 
|  | VREV64,       // reverse elements within 64-bit doublewords | 
|  | VREV32,       // reverse elements within 32-bit words | 
|  | VREV16,       // reverse elements within 16-bit halfwords | 
|  | VZIP,         // zip (interleave) | 
|  | VUZP,         // unzip (deinterleave) | 
|  | VTRN,         // transpose | 
|  | VTBL1,        // 1-register shuffle with mask | 
|  | VTBL2,        // 2-register shuffle with mask | 
|  |  | 
|  | // Vector multiply long: | 
|  | VMULLs,       // ...signed | 
|  | VMULLu,       // ...unsigned | 
|  |  | 
|  | SMULWB,       // Signed multiply word by half word, bottom | 
|  | SMULWT,       // Signed multiply word by half word, top | 
|  | UMLAL,        // 64bit Unsigned Accumulate Multiply | 
|  | SMLAL,        // 64bit Signed Accumulate Multiply | 
|  | UMAAL,        // 64-bit Unsigned Accumulate Accumulate Multiply | 
|  | SMLALBB,      // 64-bit signed accumulate multiply bottom, bottom 16 | 
|  | SMLALBT,      // 64-bit signed accumulate multiply bottom, top 16 | 
|  | SMLALTB,      // 64-bit signed accumulate multiply top, bottom 16 | 
|  | SMLALTT,      // 64-bit signed accumulate multiply top, top 16 | 
|  | SMLALD,       // Signed multiply accumulate long dual | 
|  | SMLALDX,      // Signed multiply accumulate long dual exchange | 
|  | SMLSLD,       // Signed multiply subtract long dual | 
|  | SMLSLDX,      // Signed multiply subtract long dual exchange | 
|  | SMMLAR,       // Signed multiply long, round and add | 
|  | SMMLSR,       // Signed multiply long, subtract and round | 
|  |  | 
|  | // Operands of the standard BUILD_VECTOR node are not legalized, which | 
|  | // is fine if BUILD_VECTORs are always lowered to shuffles or other | 
|  | // operations, but for ARM some BUILD_VECTORs are legal as-is and their | 
|  | // operands need to be legalized.  Define an ARM-specific version of | 
|  | // BUILD_VECTOR for this purpose. | 
|  | BUILD_VECTOR, | 
|  |  | 
|  | // Bit-field insert | 
|  | BFI, | 
|  |  | 
|  | // Vector OR with immediate | 
|  | VORRIMM, | 
|  | // Vector AND with NOT of immediate | 
|  | VBICIMM, | 
|  |  | 
|  | // Vector bitwise select | 
|  | VBSL, | 
|  |  | 
|  | // Pseudo-instruction representing a memory copy using ldm/stm | 
|  | // instructions. | 
|  | MEMCPY, | 
|  |  | 
|  | // V8.1MMainline condition select | 
|  | CSINV, // Conditional select invert. | 
|  | CSNEG, // Conditional select negate. | 
|  | CSINC, // Conditional select increment. | 
|  |  | 
|  | // Vector load N-element structure to all lanes: | 
|  | VLD1DUP = ISD::FIRST_TARGET_MEMORY_OPCODE, | 
|  | VLD2DUP, | 
|  | VLD3DUP, | 
|  | VLD4DUP, | 
|  |  | 
|  | // NEON loads with post-increment base updates: | 
|  | VLD1_UPD, | 
|  | VLD2_UPD, | 
|  | VLD3_UPD, | 
|  | VLD4_UPD, | 
|  | VLD2LN_UPD, | 
|  | VLD3LN_UPD, | 
|  | VLD4LN_UPD, | 
|  | VLD1DUP_UPD, | 
|  | VLD2DUP_UPD, | 
|  | VLD3DUP_UPD, | 
|  | VLD4DUP_UPD, | 
|  |  | 
|  | // NEON stores with post-increment base updates: | 
|  | VST1_UPD, | 
|  | VST2_UPD, | 
|  | VST3_UPD, | 
|  | VST4_UPD, | 
|  | VST2LN_UPD, | 
|  | VST3LN_UPD, | 
|  | VST4LN_UPD | 
|  | }; | 
|  |  | 
|  | } // end namespace ARMISD | 
|  |  | 
|  | /// Define some predicates that are used for node matching. | 
|  | namespace ARM { | 
|  |  | 
|  | bool isBitFieldInvertedMask(unsigned v); | 
|  |  | 
|  | } // end namespace ARM | 
|  |  | 
|  | //===--------------------------------------------------------------------===// | 
|  | //  ARMTargetLowering - ARM Implementation of the TargetLowering interface | 
|  |  | 
|  | class ARMTargetLowering : public TargetLowering { | 
|  | public: | 
|  | explicit ARMTargetLowering(const TargetMachine &TM, | 
|  | const ARMSubtarget &STI); | 
|  |  | 
|  | unsigned getJumpTableEncoding() const override; | 
|  | bool useSoftFloat() const override; | 
|  |  | 
|  | SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override; | 
|  |  | 
|  | /// ReplaceNodeResults - Replace the results of node with an illegal result | 
|  | /// type with new values built out of custom code. | 
|  | void ReplaceNodeResults(SDNode *N, SmallVectorImpl<SDValue>&Results, | 
|  | SelectionDAG &DAG) const override; | 
|  |  | 
|  | const char *getTargetNodeName(unsigned Opcode) const override; | 
|  |  | 
|  | bool isSelectSupported(SelectSupportKind Kind) const override { | 
|  | // ARM does not support scalar condition selects on vectors. | 
|  | return (Kind != ScalarCondVectorVal); | 
|  | } | 
|  |  | 
|  | bool isReadOnly(const GlobalValue *GV) const; | 
|  |  | 
|  | /// getSetCCResultType - Return the value type to use for ISD::SETCC. | 
|  | EVT getSetCCResultType(const DataLayout &DL, LLVMContext &Context, | 
|  | EVT VT) const override; | 
|  |  | 
|  | MachineBasicBlock * | 
|  | EmitInstrWithCustomInserter(MachineInstr &MI, | 
|  | MachineBasicBlock *MBB) const override; | 
|  |  | 
|  | void AdjustInstrPostInstrSelection(MachineInstr &MI, | 
|  | SDNode *Node) const override; | 
|  |  | 
|  | SDValue PerformCMOVCombine(SDNode *N, SelectionDAG &DAG) const; | 
|  | SDValue PerformBRCONDCombine(SDNode *N, SelectionDAG &DAG) const; | 
|  | SDValue PerformCMOVToBFICombine(SDNode *N, SelectionDAG &DAG) const; | 
|  | SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const override; | 
|  |  | 
|  | bool isDesirableToTransformToIntegerOp(unsigned Opc, EVT VT) const override; | 
|  |  | 
|  | /// allowsMisalignedMemoryAccesses - Returns true if the target allows | 
|  | /// unaligned memory accesses of the specified type. Returns whether it | 
|  | /// is "fast" by reference in the second argument. | 
|  | bool allowsMisalignedMemoryAccesses(EVT VT, unsigned AddrSpace, | 
|  | unsigned Align, | 
|  | MachineMemOperand::Flags Flags, | 
|  | bool *Fast) const override; | 
|  |  | 
|  | EVT getOptimalMemOpType(uint64_t Size, | 
|  | unsigned DstAlign, unsigned SrcAlign, | 
|  | bool IsMemset, bool ZeroMemset, | 
|  | bool MemcpyStrSrc, | 
|  | const AttributeList &FuncAttributes) const override; | 
|  |  | 
|  | bool isTruncateFree(Type *SrcTy, Type *DstTy) const override; | 
|  | bool isTruncateFree(EVT SrcVT, EVT DstVT) const override; | 
|  | bool isZExtFree(SDValue Val, EVT VT2) const override; | 
|  | bool shouldSinkOperands(Instruction *I, | 
|  | SmallVectorImpl<Use *> &Ops) const override; | 
|  |  | 
|  | bool isFNegFree(EVT VT) const override; | 
|  |  | 
|  | bool isVectorLoadExtDesirable(SDValue ExtVal) const override; | 
|  |  | 
|  | bool allowTruncateForTailCall(Type *Ty1, Type *Ty2) const override; | 
|  |  | 
|  |  | 
|  | /// isLegalAddressingMode - Return true if the addressing mode represented | 
|  | /// by AM is legal for this target, for a load/store of the specified type. | 
|  | bool isLegalAddressingMode(const DataLayout &DL, const AddrMode &AM, | 
|  | Type *Ty, unsigned AS, | 
|  | Instruction *I = nullptr) const override; | 
|  |  | 
|  | /// getScalingFactorCost - Return the cost of the scaling used in | 
|  | /// addressing mode represented by AM. | 
|  | /// If the AM is supported, the return value must be >= 0. | 
|  | /// If the AM is not supported, the return value must be negative. | 
|  | int getScalingFactorCost(const DataLayout &DL, const AddrMode &AM, Type *Ty, | 
|  | unsigned AS) const override; | 
|  |  | 
|  | bool isLegalT2ScaledAddressingMode(const AddrMode &AM, EVT VT) const; | 
|  |  | 
|  | /// Returns true if the addresing mode representing by AM is legal | 
|  | /// for the Thumb1 target, for a load/store of the specified type. | 
|  | bool isLegalT1ScaledAddressingMode(const AddrMode &AM, EVT VT) const; | 
|  |  | 
|  | /// isLegalICmpImmediate - Return true if the specified immediate is legal | 
|  | /// icmp immediate, that is the target has icmp instructions which can | 
|  | /// compare a register against the immediate without having to materialize | 
|  | /// the immediate into a register. | 
|  | bool isLegalICmpImmediate(int64_t Imm) const override; | 
|  |  | 
|  | /// isLegalAddImmediate - Return true if the specified immediate is legal | 
|  | /// add immediate, that is the target has add instructions which can | 
|  | /// add a register and the immediate without having to materialize | 
|  | /// the immediate into a register. | 
|  | bool isLegalAddImmediate(int64_t Imm) const override; | 
|  |  | 
|  | /// getPreIndexedAddressParts - returns true by value, base pointer and | 
|  | /// offset pointer and addressing mode by reference if the node's address | 
|  | /// can be legally represented as pre-indexed load / store address. | 
|  | bool getPreIndexedAddressParts(SDNode *N, SDValue &Base, SDValue &Offset, | 
|  | ISD::MemIndexedMode &AM, | 
|  | SelectionDAG &DAG) const override; | 
|  |  | 
|  | /// getPostIndexedAddressParts - returns true by value, base pointer and | 
|  | /// offset pointer and addressing mode by reference if this node can be | 
|  | /// combined with a load / store to form a post-indexed load / store. | 
|  | bool getPostIndexedAddressParts(SDNode *N, SDNode *Op, SDValue &Base, | 
|  | SDValue &Offset, ISD::MemIndexedMode &AM, | 
|  | SelectionDAG &DAG) const override; | 
|  |  | 
|  | void computeKnownBitsForTargetNode(const SDValue Op, KnownBits &Known, | 
|  | const APInt &DemandedElts, | 
|  | const SelectionDAG &DAG, | 
|  | unsigned Depth) const override; | 
|  |  | 
|  | bool targetShrinkDemandedConstant(SDValue Op, const APInt &Demanded, | 
|  | TargetLoweringOpt &TLO) const override; | 
|  |  | 
|  |  | 
|  | bool ExpandInlineAsm(CallInst *CI) const override; | 
|  |  | 
|  | ConstraintType getConstraintType(StringRef Constraint) const override; | 
|  |  | 
|  | /// Examine constraint string and operand type and determine a weight value. | 
|  | /// The operand object must already have been set up with the operand type. | 
|  | ConstraintWeight getSingleConstraintMatchWeight( | 
|  | AsmOperandInfo &info, const char *constraint) const override; | 
|  |  | 
|  | std::pair<unsigned, const TargetRegisterClass *> | 
|  | getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI, | 
|  | StringRef Constraint, MVT VT) const override; | 
|  |  | 
|  | const char *LowerXConstraint(EVT ConstraintVT) const override; | 
|  |  | 
|  | /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops | 
|  | /// vector.  If it is invalid, don't add anything to Ops. If hasMemory is | 
|  | /// true it means one of the asm constraint of the inline asm instruction | 
|  | /// being processed is 'm'. | 
|  | void LowerAsmOperandForConstraint(SDValue Op, std::string &Constraint, | 
|  | std::vector<SDValue> &Ops, | 
|  | SelectionDAG &DAG) const override; | 
|  |  | 
|  | unsigned | 
|  | getInlineAsmMemConstraint(StringRef ConstraintCode) const override { | 
|  | if (ConstraintCode == "Q") | 
|  | return InlineAsm::Constraint_Q; | 
|  | else if (ConstraintCode == "o") | 
|  | return InlineAsm::Constraint_o; | 
|  | else if (ConstraintCode.size() == 2) { | 
|  | if (ConstraintCode[0] == 'U') { | 
|  | switch(ConstraintCode[1]) { | 
|  | default: | 
|  | break; | 
|  | case 'm': | 
|  | return InlineAsm::Constraint_Um; | 
|  | case 'n': | 
|  | return InlineAsm::Constraint_Un; | 
|  | case 'q': | 
|  | return InlineAsm::Constraint_Uq; | 
|  | case 's': | 
|  | return InlineAsm::Constraint_Us; | 
|  | case 't': | 
|  | return InlineAsm::Constraint_Ut; | 
|  | case 'v': | 
|  | return InlineAsm::Constraint_Uv; | 
|  | case 'y': | 
|  | return InlineAsm::Constraint_Uy; | 
|  | } | 
|  | } | 
|  | } | 
|  | return TargetLowering::getInlineAsmMemConstraint(ConstraintCode); | 
|  | } | 
|  |  | 
|  | const ARMSubtarget* getSubtarget() const { | 
|  | return Subtarget; | 
|  | } | 
|  |  | 
|  | /// getRegClassFor - Return the register class that should be used for the | 
|  | /// specified value type. | 
|  | const TargetRegisterClass * | 
|  | getRegClassFor(MVT VT, bool isDivergent = false) const override; | 
|  |  | 
|  | /// Returns true if a cast between SrcAS and DestAS is a noop. | 
|  | bool isNoopAddrSpaceCast(unsigned SrcAS, unsigned DestAS) const override { | 
|  | // Addrspacecasts are always noops. | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool shouldAlignPointerArgs(CallInst *CI, unsigned &MinSize, | 
|  | unsigned &PrefAlign) const override; | 
|  |  | 
|  | /// createFastISel - This method returns a target specific FastISel object, | 
|  | /// or null if the target does not support "fast" ISel. | 
|  | FastISel *createFastISel(FunctionLoweringInfo &funcInfo, | 
|  | const TargetLibraryInfo *libInfo) const override; | 
|  |  | 
|  | Sched::Preference getSchedulingPreference(SDNode *N) const override; | 
|  |  | 
|  | bool | 
|  | isShuffleMaskLegal(ArrayRef<int> M, EVT VT) const override; | 
|  | bool isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const override; | 
|  |  | 
|  | /// isFPImmLegal - Returns true if the target can instruction select the | 
|  | /// specified FP immediate natively. If false, the legalizer will | 
|  | /// materialize the FP immediate as a load from a constant pool. | 
|  | bool isFPImmLegal(const APFloat &Imm, EVT VT, | 
|  | bool ForCodeSize = false) const override; | 
|  |  | 
|  | bool getTgtMemIntrinsic(IntrinsicInfo &Info, | 
|  | const CallInst &I, | 
|  | MachineFunction &MF, | 
|  | unsigned Intrinsic) const override; | 
|  |  | 
|  | /// Returns true if it is beneficial to convert a load of a constant | 
|  | /// to just the constant itself. | 
|  | bool shouldConvertConstantLoadToIntImm(const APInt &Imm, | 
|  | Type *Ty) const override; | 
|  |  | 
|  | /// Return true if EXTRACT_SUBVECTOR is cheap for this result type | 
|  | /// with this index. | 
|  | bool isExtractSubvectorCheap(EVT ResVT, EVT SrcVT, | 
|  | unsigned Index) const override; | 
|  |  | 
|  | /// Returns true if an argument of type Ty needs to be passed in a | 
|  | /// contiguous block of registers in calling convention CallConv. | 
|  | bool functionArgumentNeedsConsecutiveRegisters( | 
|  | Type *Ty, CallingConv::ID CallConv, bool isVarArg) const override; | 
|  |  | 
|  | /// If a physical register, this returns the register that receives the | 
|  | /// exception address on entry to an EH pad. | 
|  | unsigned | 
|  | getExceptionPointerRegister(const Constant *PersonalityFn) const override; | 
|  |  | 
|  | /// If a physical register, this returns the register that receives the | 
|  | /// exception typeid on entry to a landing pad. | 
|  | unsigned | 
|  | getExceptionSelectorRegister(const Constant *PersonalityFn) const override; | 
|  |  | 
|  | Instruction *makeDMB(IRBuilder<> &Builder, ARM_MB::MemBOpt Domain) const; | 
|  | Value *emitLoadLinked(IRBuilder<> &Builder, Value *Addr, | 
|  | AtomicOrdering Ord) const override; | 
|  | Value *emitStoreConditional(IRBuilder<> &Builder, Value *Val, | 
|  | Value *Addr, AtomicOrdering Ord) const override; | 
|  |  | 
|  | void emitAtomicCmpXchgNoStoreLLBalance(IRBuilder<> &Builder) const override; | 
|  |  | 
|  | Instruction *emitLeadingFence(IRBuilder<> &Builder, Instruction *Inst, | 
|  | AtomicOrdering Ord) const override; | 
|  | Instruction *emitTrailingFence(IRBuilder<> &Builder, Instruction *Inst, | 
|  | AtomicOrdering Ord) const override; | 
|  |  | 
|  | unsigned getMaxSupportedInterleaveFactor() const override; | 
|  |  | 
|  | bool lowerInterleavedLoad(LoadInst *LI, | 
|  | ArrayRef<ShuffleVectorInst *> Shuffles, | 
|  | ArrayRef<unsigned> Indices, | 
|  | unsigned Factor) const override; | 
|  | bool lowerInterleavedStore(StoreInst *SI, ShuffleVectorInst *SVI, | 
|  | unsigned Factor) const override; | 
|  |  | 
|  | bool shouldInsertFencesForAtomic(const Instruction *I) const override; | 
|  | TargetLoweringBase::AtomicExpansionKind | 
|  | shouldExpandAtomicLoadInIR(LoadInst *LI) const override; | 
|  | bool shouldExpandAtomicStoreInIR(StoreInst *SI) const override; | 
|  | TargetLoweringBase::AtomicExpansionKind | 
|  | shouldExpandAtomicRMWInIR(AtomicRMWInst *AI) const override; | 
|  | TargetLoweringBase::AtomicExpansionKind | 
|  | shouldExpandAtomicCmpXchgInIR(AtomicCmpXchgInst *AI) const override; | 
|  |  | 
|  | bool useLoadStackGuardNode() const override; | 
|  |  | 
|  | void insertSSPDeclarations(Module &M) const override; | 
|  | Value *getSDagStackGuard(const Module &M) const override; | 
|  | Function *getSSPStackGuardCheck(const Module &M) const override; | 
|  |  | 
|  | bool canCombineStoreAndExtract(Type *VectorTy, Value *Idx, | 
|  | unsigned &Cost) const override; | 
|  |  | 
|  | bool canMergeStoresTo(unsigned AddressSpace, EVT MemVT, | 
|  | const SelectionDAG &DAG) const override { | 
|  | // Do not merge to larger than i32. | 
|  | return (MemVT.getSizeInBits() <= 32); | 
|  | } | 
|  |  | 
|  | bool isCheapToSpeculateCttz() const override; | 
|  | bool isCheapToSpeculateCtlz() const override; | 
|  |  | 
|  | bool convertSetCCLogicToBitwiseLogic(EVT VT) const override { | 
|  | return VT.isScalarInteger(); | 
|  | } | 
|  |  | 
|  | bool supportSwiftError() const override { | 
|  | return true; | 
|  | } | 
|  |  | 
|  | bool hasStandaloneRem(EVT VT) const override { | 
|  | return HasStandaloneRem; | 
|  | } | 
|  |  | 
|  | bool shouldExpandShift(SelectionDAG &DAG, SDNode *N) const override; | 
|  |  | 
|  | CCAssignFn *CCAssignFnForCall(CallingConv::ID CC, bool isVarArg) const; | 
|  | CCAssignFn *CCAssignFnForReturn(CallingConv::ID CC, bool isVarArg) const; | 
|  |  | 
|  | /// Returns true if \p VecTy is a legal interleaved access type. This | 
|  | /// function checks the vector element type and the overall width of the | 
|  | /// vector. | 
|  | bool isLegalInterleavedAccessType(VectorType *VecTy, | 
|  | const DataLayout &DL) const; | 
|  |  | 
|  | bool alignLoopsWithOptSize() const override; | 
|  |  | 
|  | /// Returns the number of interleaved accesses that will be generated when | 
|  | /// lowering accesses of the given type. | 
|  | unsigned getNumInterleavedAccesses(VectorType *VecTy, | 
|  | const DataLayout &DL) const; | 
|  |  | 
|  | void finalizeLowering(MachineFunction &MF) const override; | 
|  |  | 
|  | /// Return the correct alignment for the current calling convention. | 
|  | unsigned getABIAlignmentForCallingConv(Type *ArgTy, | 
|  | DataLayout DL) const override; | 
|  |  | 
|  | bool isDesirableToCommuteWithShift(const SDNode *N, | 
|  | CombineLevel Level) const override; | 
|  |  | 
|  | bool shouldFoldConstantShiftPairToMask(const SDNode *N, | 
|  | CombineLevel Level) const override; | 
|  |  | 
|  | bool preferIncOfAddToSubOfNot(EVT VT) const override; | 
|  |  | 
|  | protected: | 
|  | std::pair<const TargetRegisterClass *, uint8_t> | 
|  | findRepresentativeClass(const TargetRegisterInfo *TRI, | 
|  | MVT VT) const override; | 
|  |  | 
|  | private: | 
|  | /// Subtarget - Keep a pointer to the ARMSubtarget around so that we can | 
|  | /// make the right decision when generating code for different targets. | 
|  | const ARMSubtarget *Subtarget; | 
|  |  | 
|  | const TargetRegisterInfo *RegInfo; | 
|  |  | 
|  | const InstrItineraryData *Itins; | 
|  |  | 
|  | /// ARMPCLabelIndex - Keep track of the number of ARM PC labels created. | 
|  | unsigned ARMPCLabelIndex; | 
|  |  | 
|  | // TODO: remove this, and have shouldInsertFencesForAtomic do the proper | 
|  | // check. | 
|  | bool InsertFencesForAtomic; | 
|  |  | 
|  | bool HasStandaloneRem = true; | 
|  |  | 
|  | void addTypeForNEON(MVT VT, MVT PromotedLdStVT, MVT PromotedBitwiseVT); | 
|  | void addDRTypeForNEON(MVT VT); | 
|  | void addQRTypeForNEON(MVT VT); | 
|  | std::pair<SDValue, SDValue> getARMXALUOOp(SDValue Op, SelectionDAG &DAG, SDValue &ARMcc) const; | 
|  |  | 
|  | using RegsToPassVector = SmallVector<std::pair<unsigned, SDValue>, 8>; | 
|  |  | 
|  | void PassF64ArgInRegs(const SDLoc &dl, SelectionDAG &DAG, SDValue Chain, | 
|  | SDValue &Arg, RegsToPassVector &RegsToPass, | 
|  | CCValAssign &VA, CCValAssign &NextVA, | 
|  | SDValue &StackPtr, | 
|  | SmallVectorImpl<SDValue> &MemOpChains, | 
|  | ISD::ArgFlagsTy Flags) const; | 
|  | SDValue GetF64FormalArgument(CCValAssign &VA, CCValAssign &NextVA, | 
|  | SDValue &Root, SelectionDAG &DAG, | 
|  | const SDLoc &dl) const; | 
|  |  | 
|  | CallingConv::ID getEffectiveCallingConv(CallingConv::ID CC, | 
|  | bool isVarArg) const; | 
|  | CCAssignFn *CCAssignFnForNode(CallingConv::ID CC, bool Return, | 
|  | bool isVarArg) const; | 
|  | SDValue LowerMemOpCallTo(SDValue Chain, SDValue StackPtr, SDValue Arg, | 
|  | const SDLoc &dl, SelectionDAG &DAG, | 
|  | const CCValAssign &VA, | 
|  | ISD::ArgFlagsTy Flags) const; | 
|  | SDValue LowerEH_SJLJ_SETJMP(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerEH_SJLJ_LONGJMP(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerEH_SJLJ_SETUP_DISPATCH(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerINTRINSIC_VOID(SDValue Op, SelectionDAG &DAG, | 
|  | const ARMSubtarget *Subtarget) const; | 
|  | SDValue LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG, | 
|  | const ARMSubtarget *Subtarget) const; | 
|  | SDValue LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerConstantPool(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerGlobalAddressDarwin(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerGlobalAddressELF(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerGlobalAddressWindows(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerToTLSGeneralDynamicModel(GlobalAddressSDNode *GA, | 
|  | SelectionDAG &DAG) const; | 
|  | SDValue LowerToTLSExecModels(GlobalAddressSDNode *GA, | 
|  | SelectionDAG &DAG, | 
|  | TLSModel::Model model) const; | 
|  | SDValue LowerGlobalTLSAddressDarwin(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerGlobalTLSAddressWindows(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerGLOBAL_OFFSET_TABLE(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerBR_JT(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerSignedALUO(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerUnsignedALUO(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerSELECT(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerBRCOND(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerShiftRightParts(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerShiftLeftParts(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerFLT_ROUNDS_(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerConstantFP(SDValue Op, SelectionDAG &DAG, | 
|  | const ARMSubtarget *ST) const; | 
|  | SDValue LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG, | 
|  | const ARMSubtarget *ST) const; | 
|  | SDValue LowerINSERT_VECTOR_ELT(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerFSINCOS(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerDivRem(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerDIV_Windows(SDValue Op, SelectionDAG &DAG, bool Signed) const; | 
|  | void ExpandDIV_Windows(SDValue Op, SelectionDAG &DAG, bool Signed, | 
|  | SmallVectorImpl<SDValue> &Results) const; | 
|  | SDValue LowerWindowsDIVLibCall(SDValue Op, SelectionDAG &DAG, bool Signed, | 
|  | SDValue &Chain) const; | 
|  | SDValue LowerREM(SDNode *N, SelectionDAG &DAG) const; | 
|  | SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerFP_ROUND(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerFP_EXTEND(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerFP_TO_INT(SDValue Op, SelectionDAG &DAG) const; | 
|  | SDValue LowerINT_TO_FP(SDValue Op, SelectionDAG &DAG) const; | 
|  | void lowerABS(SDNode *N, SmallVectorImpl<SDValue> &Results, | 
|  | SelectionDAG &DAG) const; | 
|  |  | 
|  | unsigned getRegisterByName(const char* RegName, EVT VT, | 
|  | SelectionDAG &DAG) const override; | 
|  |  | 
|  | SDValue BuildSDIVPow2(SDNode *N, const APInt &Divisor, SelectionDAG &DAG, | 
|  | SmallVectorImpl<SDNode *> &Created) const override; | 
|  |  | 
|  | /// isFMAFasterThanFMulAndFAdd - Return true if an FMA operation is faster | 
|  | /// than a pair of fmul and fadd instructions. fmuladd intrinsics will be | 
|  | /// expanded to FMAs when this method returns true, otherwise fmuladd is | 
|  | /// expanded to fmul + fadd. | 
|  | /// | 
|  | /// ARM supports both fused and unfused multiply-add operations; we already | 
|  | /// lower a pair of fmul and fadd to the latter so it's not clear that there | 
|  | /// would be a gain or that the gain would be worthwhile enough to risk | 
|  | /// correctness bugs. | 
|  | bool isFMAFasterThanFMulAndFAdd(EVT VT) const override { return false; } | 
|  |  | 
|  | SDValue ReconstructShuffle(SDValue Op, SelectionDAG &DAG) const; | 
|  |  | 
|  | SDValue LowerCallResult(SDValue Chain, SDValue InFlag, | 
|  | CallingConv::ID CallConv, bool isVarArg, | 
|  | const SmallVectorImpl<ISD::InputArg> &Ins, | 
|  | const SDLoc &dl, SelectionDAG &DAG, | 
|  | SmallVectorImpl<SDValue> &InVals, bool isThisReturn, | 
|  | SDValue ThisVal) const; | 
|  |  | 
|  | bool supportSplitCSR(MachineFunction *MF) const override { | 
|  | return MF->getFunction().getCallingConv() == CallingConv::CXX_FAST_TLS && | 
|  | MF->getFunction().hasFnAttribute(Attribute::NoUnwind); | 
|  | } | 
|  |  | 
|  | void initializeSplitCSR(MachineBasicBlock *Entry) const override; | 
|  | void insertCopiesSplitCSR( | 
|  | MachineBasicBlock *Entry, | 
|  | const SmallVectorImpl<MachineBasicBlock *> &Exits) const override; | 
|  |  | 
|  | SDValue | 
|  | LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv, bool isVarArg, | 
|  | const SmallVectorImpl<ISD::InputArg> &Ins, | 
|  | const SDLoc &dl, SelectionDAG &DAG, | 
|  | SmallVectorImpl<SDValue> &InVals) const override; | 
|  |  | 
|  | int StoreByValRegs(CCState &CCInfo, SelectionDAG &DAG, const SDLoc &dl, | 
|  | SDValue &Chain, const Value *OrigArg, | 
|  | unsigned InRegsParamRecordIdx, int ArgOffset, | 
|  | unsigned ArgSize) const; | 
|  |  | 
|  | void VarArgStyleRegisters(CCState &CCInfo, SelectionDAG &DAG, | 
|  | const SDLoc &dl, SDValue &Chain, | 
|  | unsigned ArgOffset, unsigned TotalArgRegsSaveSize, | 
|  | bool ForceMutable = false) const; | 
|  |  | 
|  | SDValue LowerCall(TargetLowering::CallLoweringInfo &CLI, | 
|  | SmallVectorImpl<SDValue> &InVals) const override; | 
|  |  | 
|  | /// HandleByVal - Target-specific cleanup for ByVal support. | 
|  | void HandleByVal(CCState *, unsigned &, unsigned) const override; | 
|  |  | 
|  | /// IsEligibleForTailCallOptimization - Check whether the call is eligible | 
|  | /// for tail call optimization. Targets which want to do tail call | 
|  | /// optimization should implement this function. | 
|  | bool IsEligibleForTailCallOptimization( | 
|  | SDValue Callee, CallingConv::ID CalleeCC, bool isVarArg, | 
|  | bool isCalleeStructRet, bool isCallerStructRet, | 
|  | const SmallVectorImpl<ISD::OutputArg> &Outs, | 
|  | const SmallVectorImpl<SDValue> &OutVals, | 
|  | const SmallVectorImpl<ISD::InputArg> &Ins, SelectionDAG &DAG, | 
|  | const bool isIndirect) const; | 
|  |  | 
|  | bool CanLowerReturn(CallingConv::ID CallConv, | 
|  | MachineFunction &MF, bool isVarArg, | 
|  | const SmallVectorImpl<ISD::OutputArg> &Outs, | 
|  | LLVMContext &Context) const override; | 
|  |  | 
|  | SDValue LowerReturn(SDValue Chain, CallingConv::ID CallConv, bool isVarArg, | 
|  | const SmallVectorImpl<ISD::OutputArg> &Outs, | 
|  | const SmallVectorImpl<SDValue> &OutVals, | 
|  | const SDLoc &dl, SelectionDAG &DAG) const override; | 
|  |  | 
|  | bool isUsedByReturnOnly(SDNode *N, SDValue &Chain) const override; | 
|  |  | 
|  | bool mayBeEmittedAsTailCall(const CallInst *CI) const override; | 
|  |  | 
|  | bool shouldConsiderGEPOffsetSplit() const override { return true; } | 
|  |  | 
|  | bool isUnsupportedFloatingType(EVT VT) const; | 
|  |  | 
|  | SDValue getCMOV(const SDLoc &dl, EVT VT, SDValue FalseVal, SDValue TrueVal, | 
|  | SDValue ARMcc, SDValue CCR, SDValue Cmp, | 
|  | SelectionDAG &DAG) const; | 
|  | SDValue getARMCmp(SDValue LHS, SDValue RHS, ISD::CondCode CC, | 
|  | SDValue &ARMcc, SelectionDAG &DAG, const SDLoc &dl) const; | 
|  | SDValue getVFPCmp(SDValue LHS, SDValue RHS, SelectionDAG &DAG, | 
|  | const SDLoc &dl, bool InvalidOnQNaN) const; | 
|  | SDValue duplicateCmp(SDValue Cmp, SelectionDAG &DAG) const; | 
|  |  | 
|  | SDValue OptimizeVFPBrcond(SDValue Op, SelectionDAG &DAG) const; | 
|  |  | 
|  | void SetupEntryBlockForSjLj(MachineInstr &MI, MachineBasicBlock *MBB, | 
|  | MachineBasicBlock *DispatchBB, int FI) const; | 
|  |  | 
|  | void EmitSjLjDispatchBlock(MachineInstr &MI, MachineBasicBlock *MBB) const; | 
|  |  | 
|  | bool RemapAddSubWithFlags(MachineInstr &MI, MachineBasicBlock *BB) const; | 
|  |  | 
|  | MachineBasicBlock *EmitStructByval(MachineInstr &MI, | 
|  | MachineBasicBlock *MBB) const; | 
|  |  | 
|  | MachineBasicBlock *EmitLowered__chkstk(MachineInstr &MI, | 
|  | MachineBasicBlock *MBB) const; | 
|  | MachineBasicBlock *EmitLowered__dbzchk(MachineInstr &MI, | 
|  | MachineBasicBlock *MBB) const; | 
|  | void addMVEVectorTypes(bool HasMVEFP); | 
|  | void addAllExtLoads(const MVT From, const MVT To, LegalizeAction Action); | 
|  | void setAllExpand(MVT VT); | 
|  | }; | 
|  |  | 
|  | enum VMOVModImmType { | 
|  | VMOVModImm, | 
|  | VMVNModImm, | 
|  | MVEVMVNModImm, | 
|  | OtherModImm | 
|  | }; | 
|  |  | 
|  | namespace ARM { | 
|  |  | 
|  | FastISel *createFastISel(FunctionLoweringInfo &funcInfo, | 
|  | const TargetLibraryInfo *libInfo); | 
|  |  | 
|  | } // end namespace ARM | 
|  |  | 
|  | } // end namespace llvm | 
|  |  | 
|  | #endif // LLVM_LIB_TARGET_ARM_ARMISELLOWERING_H |