1 //===-- ARMISelLowering.h - ARM DAG Lowering Interface ----------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines the interfaces that ARM uses to lower LLVM code into a
11 // selection DAG.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_LIB_TARGET_ARM_ARMISELLOWERING_H
16 #define LLVM_LIB_TARGET_ARM_ARMISELLOWERING_H
17 
18 #include "MCTargetDesc/ARMBaseInfo.h"
19 #include "llvm/CodeGen/CallingConvLower.h"
20 #include "llvm/CodeGen/SelectionDAG.h"
21 #include "llvm/Target/TargetLowering.h"
22 #include <vector>
23 
24 namespace llvm {
25   class ARMConstantPoolValue;
26   class ARMSubtarget;
27 
28   namespace ARMISD {
29     // ARM Specific DAG Nodes
30     enum NodeType {
31       // Start the numbering where the builtin ops and target ops leave off.
32       FIRST_NUMBER = ISD::BUILTIN_OP_END,
33 
34       Wrapper,      // Wrapper - A wrapper node for TargetConstantPool,
35                     // TargetExternalSymbol, and TargetGlobalAddress.
36       WrapperPIC,   // WrapperPIC - A wrapper node for TargetGlobalAddress in
37                     // PIC mode.
38       WrapperJT,    // WrapperJT - A wrapper node for TargetJumpTable
39 
40       // Add pseudo op to model memcpy for struct byval.
41       COPY_STRUCT_BYVAL,
42 
43       CALL,         // Function call.
44       CALL_PRED,    // Function call that's predicable.
45       CALL_NOLINK,  // Function call with branch not branch-and-link.
46       tCALL,        // Thumb function call.
47       BRCOND,       // Conditional branch.
48       BR_JT,        // Jumptable branch.
49       BR2_JT,       // Jumptable branch (2 level - jumptable entry is a jump).
50       RET_FLAG,     // Return with a flag operand.
51       INTRET_FLAG,  // Interrupt return with an LR-offset and a flag operand.
52 
53       PIC_ADD,      // Add with a PC operand and a PIC label.
54 
55       CMP,          // ARM compare instructions.
56       CMN,          // ARM CMN instructions.
57       CMPZ,         // ARM compare that sets only Z flag.
58       CMPFP,        // ARM VFP compare instruction, sets FPSCR.
59       CMPFPw0,      // ARM VFP compare against zero instruction, sets FPSCR.
60       FMSTAT,       // ARM fmstat instruction.
61 
62       CMOV,         // ARM conditional move instructions.
63 
64       BCC_i64,
65 
66       RBIT,         // ARM bitreverse instruction
67 
68       SRL_FLAG,     // V,Flag = srl_flag X -> srl X, 1 + save carry out.
69       SRA_FLAG,     // V,Flag = sra_flag X -> sra X, 1 + save carry out.
70       RRX,          // V = RRX X, Flag     -> srl X, 1 + shift in carry flag.
71 
72       ADDC,         // Add with carry
73       ADDE,         // Add using carry
74       SUBC,         // Sub with carry
75       SUBE,         // Sub using carry
76 
77       VMOVRRD,      // double to two gprs.
78       VMOVDRR,      // Two gprs to double.
79 
80       EH_SJLJ_SETJMP,         // SjLj exception handling setjmp.
81       EH_SJLJ_LONGJMP,        // SjLj exception handling longjmp.
82 
83       TC_RETURN,    // Tail call return pseudo.
84 
85       THREAD_POINTER,
86 
87       DYN_ALLOC,    // Dynamic allocation on the stack.
88 
89       MEMBARRIER_MCR, // Memory barrier (MCR)
90 
91       PRELOAD,      // Preload
92 
93       WIN__CHKSTK,  // Windows' __chkstk call to do stack probing.
94 
95       VCEQ,         // Vector compare equal.
96       VCEQZ,        // Vector compare equal to zero.
97       VCGE,         // Vector compare greater than or equal.
98       VCGEZ,        // Vector compare greater than or equal to zero.
99       VCLEZ,        // Vector compare less than or equal to zero.
100       VCGEU,        // Vector compare unsigned greater than or equal.
101       VCGT,         // Vector compare greater than.
102       VCGTZ,        // Vector compare greater than zero.
103       VCLTZ,        // Vector compare less than zero.
104       VCGTU,        // Vector compare unsigned greater than.
105       VTST,         // Vector test bits.
106 
107       // Vector shift by immediate:
108       VSHL,         // ...left
109       VSHRs,        // ...right (signed)
110       VSHRu,        // ...right (unsigned)
111 
112       // Vector rounding shift by immediate:
113       VRSHRs,       // ...right (signed)
114       VRSHRu,       // ...right (unsigned)
115       VRSHRN,       // ...right narrow
116 
117       // Vector saturating shift by immediate:
118       VQSHLs,       // ...left (signed)
119       VQSHLu,       // ...left (unsigned)
120       VQSHLsu,      // ...left (signed to unsigned)
121       VQSHRNs,      // ...right narrow (signed)
122       VQSHRNu,      // ...right narrow (unsigned)
123       VQSHRNsu,     // ...right narrow (signed to unsigned)
124 
125       // Vector saturating rounding shift by immediate:
126       VQRSHRNs,     // ...right narrow (signed)
127       VQRSHRNu,     // ...right narrow (unsigned)
128       VQRSHRNsu,    // ...right narrow (signed to unsigned)
129 
130       // Vector shift and insert:
131       VSLI,         // ...left
132       VSRI,         // ...right
133 
134       // Vector get lane (VMOV scalar to ARM core register)
135       // (These are used for 8- and 16-bit element types only.)
136       VGETLANEu,    // zero-extend vector extract element
137       VGETLANEs,    // sign-extend vector extract element
138 
139       // Vector move immediate and move negated immediate:
140       VMOVIMM,
141       VMVNIMM,
142 
143       // Vector move f32 immediate:
144       VMOVFPIMM,
145 
146       // Vector duplicate:
147       VDUP,
148       VDUPLANE,
149 
150       // Vector shuffles:
151       VEXT,         // extract
152       VREV64,       // reverse elements within 64-bit doublewords
153       VREV32,       // reverse elements within 32-bit words
154       VREV16,       // reverse elements within 16-bit halfwords
155       VZIP,         // zip (interleave)
156       VUZP,         // unzip (deinterleave)
157       VTRN,         // transpose
158       VTBL1,        // 1-register shuffle with mask
159       VTBL2,        // 2-register shuffle with mask
160 
161       // Vector multiply long:
162       VMULLs,       // ...signed
163       VMULLu,       // ...unsigned
164 
165       UMLAL,        // 64bit Unsigned Accumulate Multiply
166       SMLAL,        // 64bit Signed Accumulate Multiply
167 
168       // Operands of the standard BUILD_VECTOR node are not legalized, which
169       // is fine if BUILD_VECTORs are always lowered to shuffles or other
170       // operations, but for ARM some BUILD_VECTORs are legal as-is and their
171       // operands need to be legalized.  Define an ARM-specific version of
172       // BUILD_VECTOR for this purpose.
173       BUILD_VECTOR,
174 
175       // Floating-point max and min:
176       FMAX,
177       FMIN,
178       VMAXNM,
179       VMINNM,
180 
181       // Bit-field insert
182       BFI,
183 
184       // Vector OR with immediate
185       VORRIMM,
186       // Vector AND with NOT of immediate
187       VBICIMM,
188 
189       // Vector bitwise select
190       VBSL,
191 
192       // Vector load N-element structure to all lanes:
193       VLD2DUP = ISD::FIRST_TARGET_MEMORY_OPCODE,
194       VLD3DUP,
195       VLD4DUP,
196 
197       // NEON loads with post-increment base updates:
198       VLD1_UPD,
199       VLD2_UPD,
200       VLD3_UPD,
201       VLD4_UPD,
202       VLD2LN_UPD,
203       VLD3LN_UPD,
204       VLD4LN_UPD,
205       VLD2DUP_UPD,
206       VLD3DUP_UPD,
207       VLD4DUP_UPD,
208 
209       // NEON stores with post-increment base updates:
210       VST1_UPD,
211       VST2_UPD,
212       VST3_UPD,
213       VST4_UPD,
214       VST2LN_UPD,
215       VST3LN_UPD,
216       VST4LN_UPD
217     };
218   }
219 
220   /// Define some predicates that are used for node matching.
221   namespace ARM {
222     bool isBitFieldInvertedMask(unsigned v);
223   }
224 
225   //===--------------------------------------------------------------------===//
226   //  ARMTargetLowering - ARM Implementation of the TargetLowering interface
227 
228   class ARMTargetLowering : public TargetLowering {
229   public:
230     explicit ARMTargetLowering(const TargetMachine &TM,
231                                const ARMSubtarget &STI);
232 
233     unsigned getJumpTableEncoding() const override;
234 
235     SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override;
236 
237     /// ReplaceNodeResults - Replace the results of node with an illegal result
238     /// type with new values built out of custom code.
239     ///
240     void ReplaceNodeResults(SDNode *N, SmallVectorImpl<SDValue>&Results,
241                             SelectionDAG &DAG) const override;
242 
243     const char *getTargetNodeName(unsigned Opcode) const override;
244 
isSelectSupported(SelectSupportKind Kind)245     bool isSelectSupported(SelectSupportKind Kind) const override {
246       // ARM does not support scalar condition selects on vectors.
247       return (Kind != ScalarCondVectorVal);
248     }
249 
250     /// getSetCCResultType - Return the value type to use for ISD::SETCC.
251     EVT getSetCCResultType(LLVMContext &Context, EVT VT) const override;
252 
253     MachineBasicBlock *
254       EmitInstrWithCustomInserter(MachineInstr *MI,
255                                   MachineBasicBlock *MBB) const override;
256 
257     void AdjustInstrPostInstrSelection(MachineInstr *MI,
258                                        SDNode *Node) const override;
259 
260     SDValue PerformCMOVCombine(SDNode *N, SelectionDAG &DAG) const;
261     SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const override;
262 
263     bool isDesirableToTransformToIntegerOp(unsigned Opc, EVT VT) const override;
264 
265     /// allowsMisalignedMemoryAccesses - Returns true if the target allows
266     /// unaligned memory accesses of the specified type. Returns whether it
267     /// is "fast" by reference in the second argument.
268     bool allowsMisalignedMemoryAccesses(EVT VT, unsigned AddrSpace,
269                                         unsigned Align,
270                                         bool *Fast) const override;
271 
272     EVT getOptimalMemOpType(uint64_t Size,
273                             unsigned DstAlign, unsigned SrcAlign,
274                             bool IsMemset, bool ZeroMemset,
275                             bool MemcpyStrSrc,
276                             MachineFunction &MF) const override;
277 
278     using TargetLowering::isZExtFree;
279     bool isZExtFree(SDValue Val, EVT VT2) const override;
280 
281     bool isVectorLoadExtDesirable(SDValue ExtVal) const override;
282 
283     bool allowTruncateForTailCall(Type *Ty1, Type *Ty2) const override;
284 
285 
286     /// isLegalAddressingMode - Return true if the addressing mode represented
287     /// by AM is legal for this target, for a load/store of the specified type.
288     bool isLegalAddressingMode(const AddrMode &AM, Type *Ty) const override;
289     bool isLegalT2ScaledAddressingMode(const AddrMode &AM, EVT VT) const;
290 
291     /// isLegalICmpImmediate - Return true if the specified immediate is legal
292     /// icmp immediate, that is the target has icmp instructions which can
293     /// compare a register against the immediate without having to materialize
294     /// the immediate into a register.
295     bool isLegalICmpImmediate(int64_t Imm) const override;
296 
297     /// isLegalAddImmediate - Return true if the specified immediate is legal
298     /// add immediate, that is the target has add instructions which can
299     /// add a register and the immediate without having to materialize
300     /// the immediate into a register.
301     bool isLegalAddImmediate(int64_t Imm) const override;
302 
303     /// getPreIndexedAddressParts - returns true by value, base pointer and
304     /// offset pointer and addressing mode by reference if the node's address
305     /// can be legally represented as pre-indexed load / store address.
306     bool getPreIndexedAddressParts(SDNode *N, SDValue &Base, SDValue &Offset,
307                                    ISD::MemIndexedMode &AM,
308                                    SelectionDAG &DAG) const override;
309 
310     /// getPostIndexedAddressParts - returns true by value, base pointer and
311     /// offset pointer and addressing mode by reference if this node can be
312     /// combined with a load / store to form a post-indexed load / store.
313     bool getPostIndexedAddressParts(SDNode *N, SDNode *Op, SDValue &Base,
314                                     SDValue &Offset, ISD::MemIndexedMode &AM,
315                                     SelectionDAG &DAG) const override;
316 
317     void computeKnownBitsForTargetNode(const SDValue Op, APInt &KnownZero,
318                                        APInt &KnownOne,
319                                        const SelectionDAG &DAG,
320                                        unsigned Depth) const override;
321 
322 
323     bool ExpandInlineAsm(CallInst *CI) const override;
324 
325     ConstraintType
326       getConstraintType(const std::string &Constraint) const override;
327 
328     /// Examine constraint string and operand type and determine a weight value.
329     /// The operand object must already have been set up with the operand type.
330     ConstraintWeight getSingleConstraintMatchWeight(
331       AsmOperandInfo &info, const char *constraint) const override;
332 
333     std::pair<unsigned, const TargetRegisterClass *>
334     getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
335                                  const std::string &Constraint,
336                                  MVT VT) const override;
337 
338     /// LowerAsmOperandForConstraint - Lower the specified operand into the Ops
339     /// vector.  If it is invalid, don't add anything to Ops. If hasMemory is
340     /// true it means one of the asm constraint of the inline asm instruction
341     /// being processed is 'm'.
342     void LowerAsmOperandForConstraint(SDValue Op, std::string &Constraint,
343                                       std::vector<SDValue> &Ops,
344                                       SelectionDAG &DAG) const override;
345 
getInlineAsmMemConstraint(const std::string & ConstraintCode)346     unsigned getInlineAsmMemConstraint(
347         const std::string &ConstraintCode) const override {
348       // FIXME: Map different constraints differently.
349       return InlineAsm::Constraint_m;
350     }
351 
getSubtarget()352     const ARMSubtarget* getSubtarget() const {
353       return Subtarget;
354     }
355 
356     /// getRegClassFor - Return the register class that should be used for the
357     /// specified value type.
358     const TargetRegisterClass *getRegClassFor(MVT VT) const override;
359 
360     /// Returns true if a cast between SrcAS and DestAS is a noop.
isNoopAddrSpaceCast(unsigned SrcAS,unsigned DestAS)361     bool isNoopAddrSpaceCast(unsigned SrcAS, unsigned DestAS) const override {
362       // Addrspacecasts are always noops.
363       return true;
364     }
365 
366     bool shouldAlignPointerArgs(CallInst *CI, unsigned &MinSize,
367                                 unsigned &PrefAlign) const override;
368 
369     /// createFastISel - This method returns a target specific FastISel object,
370     /// or null if the target does not support "fast" ISel.
371     FastISel *createFastISel(FunctionLoweringInfo &funcInfo,
372                              const TargetLibraryInfo *libInfo) const override;
373 
374     Sched::Preference getSchedulingPreference(SDNode *N) const override;
375 
376     bool
377     isShuffleMaskLegal(const SmallVectorImpl<int> &M, EVT VT) const override;
378     bool isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const override;
379 
380     /// isFPImmLegal - Returns true if the target can instruction select the
381     /// specified FP immediate natively. If false, the legalizer will
382     /// materialize the FP immediate as a load from a constant pool.
383     bool isFPImmLegal(const APFloat &Imm, EVT VT) const override;
384 
385     bool getTgtMemIntrinsic(IntrinsicInfo &Info,
386                             const CallInst &I,
387                             unsigned Intrinsic) const override;
388 
389     /// \brief Returns true if it is beneficial to convert a load of a constant
390     /// to just the constant itself.
391     bool shouldConvertConstantLoadToIntImm(const APInt &Imm,
392                                            Type *Ty) const override;
393 
394     /// \brief Returns true if an argument of type Ty needs to be passed in a
395     /// contiguous block of registers in calling convention CallConv.
396     bool functionArgumentNeedsConsecutiveRegisters(
397         Type *Ty, CallingConv::ID CallConv, bool isVarArg) const override;
398 
399     bool hasLoadLinkedStoreConditional() const override;
400     Instruction *makeDMB(IRBuilder<> &Builder, ARM_MB::MemBOpt Domain) const;
401     Value *emitLoadLinked(IRBuilder<> &Builder, Value *Addr,
402                           AtomicOrdering Ord) const override;
403     Value *emitStoreConditional(IRBuilder<> &Builder, Value *Val,
404                                 Value *Addr, AtomicOrdering Ord) const override;
405 
406     Instruction* emitLeadingFence(IRBuilder<> &Builder, AtomicOrdering Ord,
407                           bool IsStore, bool IsLoad) const override;
408     Instruction* emitTrailingFence(IRBuilder<> &Builder, AtomicOrdering Ord,
409                            bool IsStore, bool IsLoad) const override;
410 
411     bool shouldExpandAtomicLoadInIR(LoadInst *LI) const override;
412     bool shouldExpandAtomicStoreInIR(StoreInst *SI) const override;
413     TargetLoweringBase::AtomicRMWExpansionKind
414     shouldExpandAtomicRMWInIR(AtomicRMWInst *AI) const override;
415 
416     bool useLoadStackGuardNode() const override;
417 
418     bool canCombineStoreAndExtract(Type *VectorTy, Value *Idx,
419                                    unsigned &Cost) const override;
420 
421   protected:
422     std::pair<const TargetRegisterClass *, uint8_t>
423     findRepresentativeClass(const TargetRegisterInfo *TRI,
424                             MVT VT) const override;
425 
426   private:
427     /// Subtarget - Keep a pointer to the ARMSubtarget around so that we can
428     /// make the right decision when generating code for different targets.
429     const ARMSubtarget *Subtarget;
430 
431     const TargetRegisterInfo *RegInfo;
432 
433     const InstrItineraryData *Itins;
434 
435     /// ARMPCLabelIndex - Keep track of the number of ARM PC labels created.
436     ///
437     unsigned ARMPCLabelIndex;
438 
439     void addTypeForNEON(MVT VT, MVT PromotedLdStVT, MVT PromotedBitwiseVT);
440     void addDRTypeForNEON(MVT VT);
441     void addQRTypeForNEON(MVT VT);
442     std::pair<SDValue, SDValue> getARMXALUOOp(SDValue Op, SelectionDAG &DAG, SDValue &ARMcc) const;
443 
444     typedef SmallVector<std::pair<unsigned, SDValue>, 8> RegsToPassVector;
445     void PassF64ArgInRegs(SDLoc dl, SelectionDAG &DAG,
446                           SDValue Chain, SDValue &Arg,
447                           RegsToPassVector &RegsToPass,
448                           CCValAssign &VA, CCValAssign &NextVA,
449                           SDValue &StackPtr,
450                           SmallVectorImpl<SDValue> &MemOpChains,
451                           ISD::ArgFlagsTy Flags) const;
452     SDValue GetF64FormalArgument(CCValAssign &VA, CCValAssign &NextVA,
453                                  SDValue &Root, SelectionDAG &DAG,
454                                  SDLoc dl) const;
455 
456     CallingConv::ID getEffectiveCallingConv(CallingConv::ID CC,
457                                             bool isVarArg) const;
458     CCAssignFn *CCAssignFnForNode(CallingConv::ID CC, bool Return,
459                                   bool isVarArg) const;
460     SDValue LowerMemOpCallTo(SDValue Chain, SDValue StackPtr, SDValue Arg,
461                              SDLoc dl, SelectionDAG &DAG,
462                              const CCValAssign &VA,
463                              ISD::ArgFlagsTy Flags) const;
464     SDValue LowerEH_SJLJ_SETJMP(SDValue Op, SelectionDAG &DAG) const;
465     SDValue LowerEH_SJLJ_LONGJMP(SDValue Op, SelectionDAG &DAG) const;
466     SDValue LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG,
467                                     const ARMSubtarget *Subtarget) const;
468     SDValue LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const;
469     SDValue LowerGlobalAddressDarwin(SDValue Op, SelectionDAG &DAG) const;
470     SDValue LowerGlobalAddressELF(SDValue Op, SelectionDAG &DAG) const;
471     SDValue LowerGlobalAddressWindows(SDValue Op, SelectionDAG &DAG) const;
472     SDValue LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const;
473     SDValue LowerToTLSGeneralDynamicModel(GlobalAddressSDNode *GA,
474                                             SelectionDAG &DAG) const;
475     SDValue LowerToTLSExecModels(GlobalAddressSDNode *GA,
476                                  SelectionDAG &DAG,
477                                  TLSModel::Model model) const;
478     SDValue LowerGLOBAL_OFFSET_TABLE(SDValue Op, SelectionDAG &DAG) const;
479     SDValue LowerBR_JT(SDValue Op, SelectionDAG &DAG) const;
480     SDValue LowerXALUO(SDValue Op, SelectionDAG &DAG) const;
481     SDValue LowerSELECT(SDValue Op, SelectionDAG &DAG) const;
482     SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
483     SDValue LowerBR_CC(SDValue Op, SelectionDAG &DAG) const;
484     SDValue LowerFCOPYSIGN(SDValue Op, SelectionDAG &DAG) const;
485     SDValue LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const;
486     SDValue LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const;
487     SDValue LowerShiftRightParts(SDValue Op, SelectionDAG &DAG) const;
488     SDValue LowerShiftLeftParts(SDValue Op, SelectionDAG &DAG) const;
489     SDValue LowerFLT_ROUNDS_(SDValue Op, SelectionDAG &DAG) const;
490     SDValue LowerConstantFP(SDValue Op, SelectionDAG &DAG,
491                             const ARMSubtarget *ST) const;
492     SDValue LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG,
493                               const ARMSubtarget *ST) const;
494     SDValue LowerFSINCOS(SDValue Op, SelectionDAG &DAG) const;
495     SDValue LowerDivRem(SDValue Op, SelectionDAG &DAG) const;
496     SDValue LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const;
497     SDValue LowerFP_ROUND(SDValue Op, SelectionDAG &DAG) const;
498     SDValue LowerFP_EXTEND(SDValue Op, SelectionDAG &DAG) const;
499     SDValue LowerFP_TO_INT(SDValue Op, SelectionDAG &DAG) const;
500     SDValue LowerINT_TO_FP(SDValue Op, SelectionDAG &DAG) const;
501 
502     unsigned getRegisterByName(const char* RegName, EVT VT) const override;
503 
504     /// isFMAFasterThanFMulAndFAdd - Return true if an FMA operation is faster
505     /// than a pair of fmul and fadd instructions. fmuladd intrinsics will be
506     /// expanded to FMAs when this method returns true, otherwise fmuladd is
507     /// expanded to fmul + fadd.
508     ///
509     /// ARM supports both fused and unfused multiply-add operations; we already
510     /// lower a pair of fmul and fadd to the latter so it's not clear that there
511     /// would be a gain or that the gain would be worthwhile enough to risk
512     /// correctness bugs.
isFMAFasterThanFMulAndFAdd(EVT VT)513     bool isFMAFasterThanFMulAndFAdd(EVT VT) const override { return false; }
514 
515     SDValue ReconstructShuffle(SDValue Op, SelectionDAG &DAG) const;
516 
517     SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
518                             CallingConv::ID CallConv, bool isVarArg,
519                             const SmallVectorImpl<ISD::InputArg> &Ins,
520                             SDLoc dl, SelectionDAG &DAG,
521                             SmallVectorImpl<SDValue> &InVals,
522                             bool isThisReturn, SDValue ThisVal) const;
523 
524     SDValue
525       LowerFormalArguments(SDValue Chain,
526                            CallingConv::ID CallConv, bool isVarArg,
527                            const SmallVectorImpl<ISD::InputArg> &Ins,
528                            SDLoc dl, SelectionDAG &DAG,
529                            SmallVectorImpl<SDValue> &InVals) const override;
530 
531     int StoreByValRegs(CCState &CCInfo, SelectionDAG &DAG,
532                        SDLoc dl, SDValue &Chain,
533                        const Value *OrigArg,
534                        unsigned InRegsParamRecordIdx,
535                        int ArgOffset,
536                        unsigned ArgSize) const;
537 
538     void VarArgStyleRegisters(CCState &CCInfo, SelectionDAG &DAG,
539                               SDLoc dl, SDValue &Chain,
540                               unsigned ArgOffset,
541                               unsigned TotalArgRegsSaveSize,
542                               bool ForceMutable = false) const;
543 
544     SDValue
545       LowerCall(TargetLowering::CallLoweringInfo &CLI,
546                 SmallVectorImpl<SDValue> &InVals) const override;
547 
548     /// HandleByVal - Target-specific cleanup for ByVal support.
549     void HandleByVal(CCState *, unsigned &, unsigned) const override;
550 
551     /// IsEligibleForTailCallOptimization - Check whether the call is eligible
552     /// for tail call optimization. Targets which want to do tail call
553     /// optimization should implement this function.
554     bool IsEligibleForTailCallOptimization(SDValue Callee,
555                                            CallingConv::ID CalleeCC,
556                                            bool isVarArg,
557                                            bool isCalleeStructRet,
558                                            bool isCallerStructRet,
559                                     const SmallVectorImpl<ISD::OutputArg> &Outs,
560                                     const SmallVectorImpl<SDValue> &OutVals,
561                                     const SmallVectorImpl<ISD::InputArg> &Ins,
562                                            SelectionDAG& DAG) const;
563 
564     bool CanLowerReturn(CallingConv::ID CallConv,
565                         MachineFunction &MF, bool isVarArg,
566                         const SmallVectorImpl<ISD::OutputArg> &Outs,
567                         LLVMContext &Context) const override;
568 
569     SDValue
570       LowerReturn(SDValue Chain,
571                   CallingConv::ID CallConv, bool isVarArg,
572                   const SmallVectorImpl<ISD::OutputArg> &Outs,
573                   const SmallVectorImpl<SDValue> &OutVals,
574                   SDLoc dl, SelectionDAG &DAG) const override;
575 
576     bool isUsedByReturnOnly(SDNode *N, SDValue &Chain) const override;
577 
578     bool mayBeEmittedAsTailCall(CallInst *CI) const override;
579 
580     SDValue getCMOV(SDLoc dl, EVT VT, SDValue FalseVal, SDValue TrueVal,
581                     SDValue ARMcc, SDValue CCR, SDValue Cmp,
582                     SelectionDAG &DAG) const;
583     SDValue getARMCmp(SDValue LHS, SDValue RHS, ISD::CondCode CC,
584                       SDValue &ARMcc, SelectionDAG &DAG, SDLoc dl) const;
585     SDValue getVFPCmp(SDValue LHS, SDValue RHS,
586                       SelectionDAG &DAG, SDLoc dl) const;
587     SDValue duplicateCmp(SDValue Cmp, SelectionDAG &DAG) const;
588 
589     SDValue OptimizeVFPBrcond(SDValue Op, SelectionDAG &DAG) const;
590 
591     void SetupEntryBlockForSjLj(MachineInstr *MI,
592                                 MachineBasicBlock *MBB,
593                                 MachineBasicBlock *DispatchBB, int FI) const;
594 
595     MachineBasicBlock *EmitSjLjDispatchBlock(MachineInstr *MI,
596                                              MachineBasicBlock *MBB) const;
597 
598     bool RemapAddSubWithFlags(MachineInstr *MI, MachineBasicBlock *BB) const;
599 
600     MachineBasicBlock *EmitStructByval(MachineInstr *MI,
601                                        MachineBasicBlock *MBB) const;
602 
603     MachineBasicBlock *EmitLowered__chkstk(MachineInstr *MI,
604                                            MachineBasicBlock *MBB) const;
605   };
606 
607   enum NEONModImmType {
608     VMOVModImm,
609     VMVNModImm,
610     OtherModImm
611   };
612 
613   namespace ARM {
614     FastISel *createFastISel(FunctionLoweringInfo &funcInfo,
615                              const TargetLibraryInfo *libInfo);
616   }
617 }
618 
619 #endif  // ARMISELLOWERING_H
620