xref: /freebsd/contrib/llvm-project/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp (revision a03411e84728e9b267056fd31c7d1d9d1dc1b01e)
1 //===- X86ISelDAGToDAG.cpp - A DAG pattern matching inst selector for X86 -===//
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 // This file defines a DAG pattern matching instruction selector for X86,
10 // converting from a legalized dag to a X86 dag.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "X86.h"
15 #include "X86MachineFunctionInfo.h"
16 #include "X86RegisterInfo.h"
17 #include "X86Subtarget.h"
18 #include "X86TargetMachine.h"
19 #include "llvm/ADT/Statistic.h"
20 #include "llvm/CodeGen/MachineModuleInfo.h"
21 #include "llvm/CodeGen/SelectionDAGISel.h"
22 #include "llvm/Config/llvm-config.h"
23 #include "llvm/IR/ConstantRange.h"
24 #include "llvm/IR/Function.h"
25 #include "llvm/IR/Instructions.h"
26 #include "llvm/IR/Intrinsics.h"
27 #include "llvm/IR/IntrinsicsX86.h"
28 #include "llvm/IR/Type.h"
29 #include "llvm/Support/Debug.h"
30 #include "llvm/Support/ErrorHandling.h"
31 #include "llvm/Support/KnownBits.h"
32 #include "llvm/Support/MathExtras.h"
33 #include <cstdint>
34 
35 using namespace llvm;
36 
37 #define DEBUG_TYPE "x86-isel"
38 #define PASS_NAME "X86 DAG->DAG Instruction Selection"
39 
40 STATISTIC(NumLoadMoved, "Number of loads moved below TokenFactor");
41 
42 static cl::opt<bool> AndImmShrink("x86-and-imm-shrink", cl::init(true),
43     cl::desc("Enable setting constant bits to reduce size of mask immediates"),
44     cl::Hidden);
45 
46 static cl::opt<bool> EnablePromoteAnyextLoad(
47     "x86-promote-anyext-load", cl::init(true),
48     cl::desc("Enable promoting aligned anyext load to wider load"), cl::Hidden);
49 
50 extern cl::opt<bool> IndirectBranchTracking;
51 
52 //===----------------------------------------------------------------------===//
53 //                      Pattern Matcher Implementation
54 //===----------------------------------------------------------------------===//
55 
56 namespace {
57   /// This corresponds to X86AddressMode, but uses SDValue's instead of register
58   /// numbers for the leaves of the matched tree.
59   struct X86ISelAddressMode {
60     enum {
61       RegBase,
62       FrameIndexBase
63     } BaseType = RegBase;
64 
65     // This is really a union, discriminated by BaseType!
66     SDValue Base_Reg;
67     int Base_FrameIndex = 0;
68 
69     unsigned Scale = 1;
70     SDValue IndexReg;
71     int32_t Disp = 0;
72     SDValue Segment;
73     const GlobalValue *GV = nullptr;
74     const Constant *CP = nullptr;
75     const BlockAddress *BlockAddr = nullptr;
76     const char *ES = nullptr;
77     MCSymbol *MCSym = nullptr;
78     int JT = -1;
79     Align Alignment;            // CP alignment.
80     unsigned char SymbolFlags = X86II::MO_NO_FLAG;  // X86II::MO_*
81     bool NegateIndex = false;
82 
83     X86ISelAddressMode() = default;
84 
85     bool hasSymbolicDisplacement() const {
86       return GV != nullptr || CP != nullptr || ES != nullptr ||
87              MCSym != nullptr || JT != -1 || BlockAddr != nullptr;
88     }
89 
90     bool hasBaseOrIndexReg() const {
91       return BaseType == FrameIndexBase ||
92              IndexReg.getNode() != nullptr || Base_Reg.getNode() != nullptr;
93     }
94 
95     /// Return true if this addressing mode is already RIP-relative.
96     bool isRIPRelative() const {
97       if (BaseType != RegBase) return false;
98       if (RegisterSDNode *RegNode =
99             dyn_cast_or_null<RegisterSDNode>(Base_Reg.getNode()))
100         return RegNode->getReg() == X86::RIP;
101       return false;
102     }
103 
104     void setBaseReg(SDValue Reg) {
105       BaseType = RegBase;
106       Base_Reg = Reg;
107     }
108 
109 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
110     void dump(SelectionDAG *DAG = nullptr) {
111       dbgs() << "X86ISelAddressMode " << this << '\n';
112       dbgs() << "Base_Reg ";
113       if (Base_Reg.getNode())
114         Base_Reg.getNode()->dump(DAG);
115       else
116         dbgs() << "nul\n";
117       if (BaseType == FrameIndexBase)
118         dbgs() << " Base.FrameIndex " << Base_FrameIndex << '\n';
119       dbgs() << " Scale " << Scale << '\n'
120              << "IndexReg ";
121       if (NegateIndex)
122         dbgs() << "negate ";
123       if (IndexReg.getNode())
124         IndexReg.getNode()->dump(DAG);
125       else
126         dbgs() << "nul\n";
127       dbgs() << " Disp " << Disp << '\n'
128              << "GV ";
129       if (GV)
130         GV->dump();
131       else
132         dbgs() << "nul";
133       dbgs() << " CP ";
134       if (CP)
135         CP->dump();
136       else
137         dbgs() << "nul";
138       dbgs() << '\n'
139              << "ES ";
140       if (ES)
141         dbgs() << ES;
142       else
143         dbgs() << "nul";
144       dbgs() << " MCSym ";
145       if (MCSym)
146         dbgs() << MCSym;
147       else
148         dbgs() << "nul";
149       dbgs() << " JT" << JT << " Align" << Alignment.value() << '\n';
150     }
151 #endif
152   };
153 }
154 
155 namespace {
156   //===--------------------------------------------------------------------===//
157   /// ISel - X86-specific code to select X86 machine instructions for
158   /// SelectionDAG operations.
159   ///
160   class X86DAGToDAGISel final : public SelectionDAGISel {
161     /// Keep a pointer to the X86Subtarget around so that we can
162     /// make the right decision when generating code for different targets.
163     const X86Subtarget *Subtarget;
164 
165     /// If true, selector should try to optimize for minimum code size.
166     bool OptForMinSize;
167 
168     /// Disable direct TLS access through segment registers.
169     bool IndirectTlsSegRefs;
170 
171   public:
172     static char ID;
173 
174     X86DAGToDAGISel() = delete;
175 
176     explicit X86DAGToDAGISel(X86TargetMachine &tm, CodeGenOpt::Level OptLevel)
177         : SelectionDAGISel(ID, tm, OptLevel), Subtarget(nullptr),
178           OptForMinSize(false), IndirectTlsSegRefs(false) {}
179 
180     bool runOnMachineFunction(MachineFunction &MF) override {
181       // Reset the subtarget each time through.
182       Subtarget = &MF.getSubtarget<X86Subtarget>();
183       IndirectTlsSegRefs = MF.getFunction().hasFnAttribute(
184                              "indirect-tls-seg-refs");
185 
186       // OptFor[Min]Size are used in pattern predicates that isel is matching.
187       OptForMinSize = MF.getFunction().hasMinSize();
188       assert((!OptForMinSize || MF.getFunction().hasOptSize()) &&
189              "OptForMinSize implies OptForSize");
190 
191       SelectionDAGISel::runOnMachineFunction(MF);
192       return true;
193     }
194 
195     void emitFunctionEntryCode() override;
196 
197     bool IsProfitableToFold(SDValue N, SDNode *U, SDNode *Root) const override;
198 
199     void PreprocessISelDAG() override;
200     void PostprocessISelDAG() override;
201 
202 // Include the pieces autogenerated from the target description.
203 #include "X86GenDAGISel.inc"
204 
205   private:
206     void Select(SDNode *N) override;
207 
208     bool foldOffsetIntoAddress(uint64_t Offset, X86ISelAddressMode &AM);
209     bool matchLoadInAddress(LoadSDNode *N, X86ISelAddressMode &AM,
210                             bool AllowSegmentRegForX32 = false);
211     bool matchWrapper(SDValue N, X86ISelAddressMode &AM);
212     bool matchAddress(SDValue N, X86ISelAddressMode &AM);
213     bool matchVectorAddress(SDValue N, X86ISelAddressMode &AM);
214     bool matchAdd(SDValue &N, X86ISelAddressMode &AM, unsigned Depth);
215     bool matchAddressRecursively(SDValue N, X86ISelAddressMode &AM,
216                                  unsigned Depth);
217     bool matchVectorAddressRecursively(SDValue N, X86ISelAddressMode &AM,
218                                        unsigned Depth);
219     bool matchAddressBase(SDValue N, X86ISelAddressMode &AM);
220     bool selectAddr(SDNode *Parent, SDValue N, SDValue &Base,
221                     SDValue &Scale, SDValue &Index, SDValue &Disp,
222                     SDValue &Segment);
223     bool selectVectorAddr(MemSDNode *Parent, SDValue BasePtr, SDValue IndexOp,
224                           SDValue ScaleOp, SDValue &Base, SDValue &Scale,
225                           SDValue &Index, SDValue &Disp, SDValue &Segment);
226     bool selectMOV64Imm32(SDValue N, SDValue &Imm);
227     bool selectLEAAddr(SDValue N, SDValue &Base,
228                        SDValue &Scale, SDValue &Index, SDValue &Disp,
229                        SDValue &Segment);
230     bool selectLEA64_32Addr(SDValue N, SDValue &Base,
231                             SDValue &Scale, SDValue &Index, SDValue &Disp,
232                             SDValue &Segment);
233     bool selectTLSADDRAddr(SDValue N, SDValue &Base,
234                            SDValue &Scale, SDValue &Index, SDValue &Disp,
235                            SDValue &Segment);
236     bool selectRelocImm(SDValue N, SDValue &Op);
237 
238     bool tryFoldLoad(SDNode *Root, SDNode *P, SDValue N,
239                      SDValue &Base, SDValue &Scale,
240                      SDValue &Index, SDValue &Disp,
241                      SDValue &Segment);
242 
243     // Convenience method where P is also root.
244     bool tryFoldLoad(SDNode *P, SDValue N,
245                      SDValue &Base, SDValue &Scale,
246                      SDValue &Index, SDValue &Disp,
247                      SDValue &Segment) {
248       return tryFoldLoad(P, P, N, Base, Scale, Index, Disp, Segment);
249     }
250 
251     bool tryFoldBroadcast(SDNode *Root, SDNode *P, SDValue N,
252                           SDValue &Base, SDValue &Scale,
253                           SDValue &Index, SDValue &Disp,
254                           SDValue &Segment);
255 
256     bool isProfitableToFormMaskedOp(SDNode *N) const;
257 
258     /// Implement addressing mode selection for inline asm expressions.
259     bool SelectInlineAsmMemoryOperand(const SDValue &Op,
260                                       unsigned ConstraintID,
261                                       std::vector<SDValue> &OutOps) override;
262 
263     void emitSpecialCodeForMain();
264 
265     inline void getAddressOperands(X86ISelAddressMode &AM, const SDLoc &DL,
266                                    MVT VT, SDValue &Base, SDValue &Scale,
267                                    SDValue &Index, SDValue &Disp,
268                                    SDValue &Segment) {
269       if (AM.BaseType == X86ISelAddressMode::FrameIndexBase)
270         Base = CurDAG->getTargetFrameIndex(
271             AM.Base_FrameIndex, TLI->getPointerTy(CurDAG->getDataLayout()));
272       else if (AM.Base_Reg.getNode())
273         Base = AM.Base_Reg;
274       else
275         Base = CurDAG->getRegister(0, VT);
276 
277       Scale = getI8Imm(AM.Scale, DL);
278 
279       // Negate the index if needed.
280       if (AM.NegateIndex) {
281         unsigned NegOpc = VT == MVT::i64 ? X86::NEG64r : X86::NEG32r;
282         SDValue Neg = SDValue(CurDAG->getMachineNode(NegOpc, DL, VT, MVT::i32,
283                                                      AM.IndexReg), 0);
284         AM.IndexReg = Neg;
285       }
286 
287       if (AM.IndexReg.getNode())
288         Index = AM.IndexReg;
289       else
290         Index = CurDAG->getRegister(0, VT);
291 
292       // These are 32-bit even in 64-bit mode since RIP-relative offset
293       // is 32-bit.
294       if (AM.GV)
295         Disp = CurDAG->getTargetGlobalAddress(AM.GV, SDLoc(),
296                                               MVT::i32, AM.Disp,
297                                               AM.SymbolFlags);
298       else if (AM.CP)
299         Disp = CurDAG->getTargetConstantPool(AM.CP, MVT::i32, AM.Alignment,
300                                              AM.Disp, AM.SymbolFlags);
301       else if (AM.ES) {
302         assert(!AM.Disp && "Non-zero displacement is ignored with ES.");
303         Disp = CurDAG->getTargetExternalSymbol(AM.ES, MVT::i32, AM.SymbolFlags);
304       } else if (AM.MCSym) {
305         assert(!AM.Disp && "Non-zero displacement is ignored with MCSym.");
306         assert(AM.SymbolFlags == 0 && "oo");
307         Disp = CurDAG->getMCSymbol(AM.MCSym, MVT::i32);
308       } else if (AM.JT != -1) {
309         assert(!AM.Disp && "Non-zero displacement is ignored with JT.");
310         Disp = CurDAG->getTargetJumpTable(AM.JT, MVT::i32, AM.SymbolFlags);
311       } else if (AM.BlockAddr)
312         Disp = CurDAG->getTargetBlockAddress(AM.BlockAddr, MVT::i32, AM.Disp,
313                                              AM.SymbolFlags);
314       else
315         Disp = CurDAG->getTargetConstant(AM.Disp, DL, MVT::i32);
316 
317       if (AM.Segment.getNode())
318         Segment = AM.Segment;
319       else
320         Segment = CurDAG->getRegister(0, MVT::i16);
321     }
322 
323     // Utility function to determine whether we should avoid selecting
324     // immediate forms of instructions for better code size or not.
325     // At a high level, we'd like to avoid such instructions when
326     // we have similar constants used within the same basic block
327     // that can be kept in a register.
328     //
329     bool shouldAvoidImmediateInstFormsForSize(SDNode *N) const {
330       uint32_t UseCount = 0;
331 
332       // Do not want to hoist if we're not optimizing for size.
333       // TODO: We'd like to remove this restriction.
334       // See the comment in X86InstrInfo.td for more info.
335       if (!CurDAG->shouldOptForSize())
336         return false;
337 
338       // Walk all the users of the immediate.
339       for (const SDNode *User : N->uses()) {
340         if (UseCount >= 2)
341           break;
342 
343         // This user is already selected. Count it as a legitimate use and
344         // move on.
345         if (User->isMachineOpcode()) {
346           UseCount++;
347           continue;
348         }
349 
350         // We want to count stores of immediates as real uses.
351         if (User->getOpcode() == ISD::STORE &&
352             User->getOperand(1).getNode() == N) {
353           UseCount++;
354           continue;
355         }
356 
357         // We don't currently match users that have > 2 operands (except
358         // for stores, which are handled above)
359         // Those instruction won't match in ISEL, for now, and would
360         // be counted incorrectly.
361         // This may change in the future as we add additional instruction
362         // types.
363         if (User->getNumOperands() != 2)
364           continue;
365 
366         // If this is a sign-extended 8-bit integer immediate used in an ALU
367         // instruction, there is probably an opcode encoding to save space.
368         auto *C = dyn_cast<ConstantSDNode>(N);
369         if (C && isInt<8>(C->getSExtValue()))
370           continue;
371 
372         // Immediates that are used for offsets as part of stack
373         // manipulation should be left alone. These are typically
374         // used to indicate SP offsets for argument passing and
375         // will get pulled into stores/pushes (implicitly).
376         if (User->getOpcode() == X86ISD::ADD ||
377             User->getOpcode() == ISD::ADD    ||
378             User->getOpcode() == X86ISD::SUB ||
379             User->getOpcode() == ISD::SUB) {
380 
381           // Find the other operand of the add/sub.
382           SDValue OtherOp = User->getOperand(0);
383           if (OtherOp.getNode() == N)
384             OtherOp = User->getOperand(1);
385 
386           // Don't count if the other operand is SP.
387           RegisterSDNode *RegNode;
388           if (OtherOp->getOpcode() == ISD::CopyFromReg &&
389               (RegNode = dyn_cast_or_null<RegisterSDNode>(
390                  OtherOp->getOperand(1).getNode())))
391             if ((RegNode->getReg() == X86::ESP) ||
392                 (RegNode->getReg() == X86::RSP))
393               continue;
394         }
395 
396         // ... otherwise, count this and move on.
397         UseCount++;
398       }
399 
400       // If we have more than 1 use, then recommend for hoisting.
401       return (UseCount > 1);
402     }
403 
404     /// Return a target constant with the specified value of type i8.
405     inline SDValue getI8Imm(unsigned Imm, const SDLoc &DL) {
406       return CurDAG->getTargetConstant(Imm, DL, MVT::i8);
407     }
408 
409     /// Return a target constant with the specified value, of type i32.
410     inline SDValue getI32Imm(unsigned Imm, const SDLoc &DL) {
411       return CurDAG->getTargetConstant(Imm, DL, MVT::i32);
412     }
413 
414     /// Return a target constant with the specified value, of type i64.
415     inline SDValue getI64Imm(uint64_t Imm, const SDLoc &DL) {
416       return CurDAG->getTargetConstant(Imm, DL, MVT::i64);
417     }
418 
419     SDValue getExtractVEXTRACTImmediate(SDNode *N, unsigned VecWidth,
420                                         const SDLoc &DL) {
421       assert((VecWidth == 128 || VecWidth == 256) && "Unexpected vector width");
422       uint64_t Index = N->getConstantOperandVal(1);
423       MVT VecVT = N->getOperand(0).getSimpleValueType();
424       return getI8Imm((Index * VecVT.getScalarSizeInBits()) / VecWidth, DL);
425     }
426 
427     SDValue getInsertVINSERTImmediate(SDNode *N, unsigned VecWidth,
428                                       const SDLoc &DL) {
429       assert((VecWidth == 128 || VecWidth == 256) && "Unexpected vector width");
430       uint64_t Index = N->getConstantOperandVal(2);
431       MVT VecVT = N->getSimpleValueType(0);
432       return getI8Imm((Index * VecVT.getScalarSizeInBits()) / VecWidth, DL);
433     }
434 
435     SDValue getPermuteVINSERTCommutedImmediate(SDNode *N, unsigned VecWidth,
436                                                const SDLoc &DL) {
437       assert(VecWidth == 128 && "Unexpected vector width");
438       uint64_t Index = N->getConstantOperandVal(2);
439       MVT VecVT = N->getSimpleValueType(0);
440       uint64_t InsertIdx = (Index * VecVT.getScalarSizeInBits()) / VecWidth;
441       assert((InsertIdx == 0 || InsertIdx == 1) && "Bad insertf128 index");
442       // vinsert(0,sub,vec) -> [sub0][vec1] -> vperm2x128(0x30,vec,sub)
443       // vinsert(1,sub,vec) -> [vec0][sub0] -> vperm2x128(0x02,vec,sub)
444       return getI8Imm(InsertIdx ? 0x02 : 0x30, DL);
445     }
446 
447     SDValue getSBBZero(SDNode *N) {
448       SDLoc dl(N);
449       MVT VT = N->getSimpleValueType(0);
450 
451       // Create zero.
452       SDVTList VTs = CurDAG->getVTList(MVT::i32, MVT::i32);
453       SDValue Zero = SDValue(
454           CurDAG->getMachineNode(X86::MOV32r0, dl, VTs, std::nullopt), 0);
455       if (VT == MVT::i64) {
456         Zero = SDValue(
457             CurDAG->getMachineNode(
458                 TargetOpcode::SUBREG_TO_REG, dl, MVT::i64,
459                 CurDAG->getTargetConstant(0, dl, MVT::i64), Zero,
460                 CurDAG->getTargetConstant(X86::sub_32bit, dl, MVT::i32)),
461             0);
462       }
463 
464       // Copy flags to the EFLAGS register and glue it to next node.
465       unsigned Opcode = N->getOpcode();
466       assert((Opcode == X86ISD::SBB || Opcode == X86ISD::SETCC_CARRY) &&
467              "Unexpected opcode for SBB materialization");
468       unsigned FlagOpIndex = Opcode == X86ISD::SBB ? 2 : 1;
469       SDValue EFLAGS =
470           CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, X86::EFLAGS,
471                                N->getOperand(FlagOpIndex), SDValue());
472 
473       // Create a 64-bit instruction if the result is 64-bits otherwise use the
474       // 32-bit version.
475       unsigned Opc = VT == MVT::i64 ? X86::SBB64rr : X86::SBB32rr;
476       MVT SBBVT = VT == MVT::i64 ? MVT::i64 : MVT::i32;
477       VTs = CurDAG->getVTList(SBBVT, MVT::i32);
478       return SDValue(
479           CurDAG->getMachineNode(Opc, dl, VTs,
480                                  {Zero, Zero, EFLAGS, EFLAGS.getValue(1)}),
481           0);
482     }
483 
484     // Helper to detect unneeded and instructions on shift amounts. Called
485     // from PatFrags in tablegen.
486     bool isUnneededShiftMask(SDNode *N, unsigned Width) const {
487       assert(N->getOpcode() == ISD::AND && "Unexpected opcode");
488       const APInt &Val = cast<ConstantSDNode>(N->getOperand(1))->getAPIntValue();
489 
490       if (Val.countr_one() >= Width)
491         return true;
492 
493       APInt Mask = Val | CurDAG->computeKnownBits(N->getOperand(0)).Zero;
494       return Mask.countr_one() >= Width;
495     }
496 
497     /// Return an SDNode that returns the value of the global base register.
498     /// Output instructions required to initialize the global base register,
499     /// if necessary.
500     SDNode *getGlobalBaseReg();
501 
502     /// Return a reference to the TargetMachine, casted to the target-specific
503     /// type.
504     const X86TargetMachine &getTargetMachine() const {
505       return static_cast<const X86TargetMachine &>(TM);
506     }
507 
508     /// Return a reference to the TargetInstrInfo, casted to the target-specific
509     /// type.
510     const X86InstrInfo *getInstrInfo() const {
511       return Subtarget->getInstrInfo();
512     }
513 
514     /// Return a condition code of the given SDNode
515     X86::CondCode getCondFromNode(SDNode *N) const;
516 
517     /// Address-mode matching performs shift-of-and to and-of-shift
518     /// reassociation in order to expose more scaled addressing
519     /// opportunities.
520     bool ComplexPatternFuncMutatesDAG() const override {
521       return true;
522     }
523 
524     bool isSExtAbsoluteSymbolRef(unsigned Width, SDNode *N) const;
525 
526     // Indicates we should prefer to use a non-temporal load for this load.
527     bool useNonTemporalLoad(LoadSDNode *N) const {
528       if (!N->isNonTemporal())
529         return false;
530 
531       unsigned StoreSize = N->getMemoryVT().getStoreSize();
532 
533       if (N->getAlign().value() < StoreSize)
534         return false;
535 
536       switch (StoreSize) {
537       default: llvm_unreachable("Unsupported store size");
538       case 4:
539       case 8:
540         return false;
541       case 16:
542         return Subtarget->hasSSE41();
543       case 32:
544         return Subtarget->hasAVX2();
545       case 64:
546         return Subtarget->hasAVX512();
547       }
548     }
549 
550     bool foldLoadStoreIntoMemOperand(SDNode *Node);
551     MachineSDNode *matchBEXTRFromAndImm(SDNode *Node);
552     bool matchBitExtract(SDNode *Node);
553     bool shrinkAndImmediate(SDNode *N);
554     bool isMaskZeroExtended(SDNode *N) const;
555     bool tryShiftAmountMod(SDNode *N);
556     bool tryShrinkShlLogicImm(SDNode *N);
557     bool tryVPTERNLOG(SDNode *N);
558     bool matchVPTERNLOG(SDNode *Root, SDNode *ParentA, SDNode *ParentB,
559                         SDNode *ParentC, SDValue A, SDValue B, SDValue C,
560                         uint8_t Imm);
561     bool tryVPTESTM(SDNode *Root, SDValue Setcc, SDValue Mask);
562     bool tryMatchBitSelect(SDNode *N);
563 
564     MachineSDNode *emitPCMPISTR(unsigned ROpc, unsigned MOpc, bool MayFoldLoad,
565                                 const SDLoc &dl, MVT VT, SDNode *Node);
566     MachineSDNode *emitPCMPESTR(unsigned ROpc, unsigned MOpc, bool MayFoldLoad,
567                                 const SDLoc &dl, MVT VT, SDNode *Node,
568                                 SDValue &InGlue);
569 
570     bool tryOptimizeRem8Extend(SDNode *N);
571 
572     bool onlyUsesZeroFlag(SDValue Flags) const;
573     bool hasNoSignFlagUses(SDValue Flags) const;
574     bool hasNoCarryFlagUses(SDValue Flags) const;
575   };
576 }
577 
578 char X86DAGToDAGISel::ID = 0;
579 
580 INITIALIZE_PASS(X86DAGToDAGISel, DEBUG_TYPE, PASS_NAME, false, false)
581 
582 // Returns true if this masked compare can be implemented legally with this
583 // type.
584 static bool isLegalMaskCompare(SDNode *N, const X86Subtarget *Subtarget) {
585   unsigned Opcode = N->getOpcode();
586   if (Opcode == X86ISD::CMPM || Opcode == X86ISD::CMPMM ||
587       Opcode == X86ISD::STRICT_CMPM || Opcode == ISD::SETCC ||
588       Opcode == X86ISD::CMPMM_SAE || Opcode == X86ISD::VFPCLASS) {
589     // We can get 256-bit 8 element types here without VLX being enabled. When
590     // this happens we will use 512-bit operations and the mask will not be
591     // zero extended.
592     EVT OpVT = N->getOperand(0).getValueType();
593     // The first operand of X86ISD::STRICT_CMPM is chain, so we need to get the
594     // second operand.
595     if (Opcode == X86ISD::STRICT_CMPM)
596       OpVT = N->getOperand(1).getValueType();
597     if (OpVT.is256BitVector() || OpVT.is128BitVector())
598       return Subtarget->hasVLX();
599 
600     return true;
601   }
602   // Scalar opcodes use 128 bit registers, but aren't subject to the VLX check.
603   if (Opcode == X86ISD::VFPCLASSS || Opcode == X86ISD::FSETCCM ||
604       Opcode == X86ISD::FSETCCM_SAE)
605     return true;
606 
607   return false;
608 }
609 
610 // Returns true if we can assume the writer of the mask has zero extended it
611 // for us.
612 bool X86DAGToDAGISel::isMaskZeroExtended(SDNode *N) const {
613   // If this is an AND, check if we have a compare on either side. As long as
614   // one side guarantees the mask is zero extended, the AND will preserve those
615   // zeros.
616   if (N->getOpcode() == ISD::AND)
617     return isLegalMaskCompare(N->getOperand(0).getNode(), Subtarget) ||
618            isLegalMaskCompare(N->getOperand(1).getNode(), Subtarget);
619 
620   return isLegalMaskCompare(N, Subtarget);
621 }
622 
623 bool
624 X86DAGToDAGISel::IsProfitableToFold(SDValue N, SDNode *U, SDNode *Root) const {
625   if (OptLevel == CodeGenOpt::None) return false;
626 
627   if (!N.hasOneUse())
628     return false;
629 
630   if (N.getOpcode() != ISD::LOAD)
631     return true;
632 
633   // Don't fold non-temporal loads if we have an instruction for them.
634   if (useNonTemporalLoad(cast<LoadSDNode>(N)))
635     return false;
636 
637   // If N is a load, do additional profitability checks.
638   if (U == Root) {
639     switch (U->getOpcode()) {
640     default: break;
641     case X86ISD::ADD:
642     case X86ISD::ADC:
643     case X86ISD::SUB:
644     case X86ISD::SBB:
645     case X86ISD::AND:
646     case X86ISD::XOR:
647     case X86ISD::OR:
648     case ISD::ADD:
649     case ISD::UADDO_CARRY:
650     case ISD::AND:
651     case ISD::OR:
652     case ISD::XOR: {
653       SDValue Op1 = U->getOperand(1);
654 
655       // If the other operand is a 8-bit immediate we should fold the immediate
656       // instead. This reduces code size.
657       // e.g.
658       // movl 4(%esp), %eax
659       // addl $4, %eax
660       // vs.
661       // movl $4, %eax
662       // addl 4(%esp), %eax
663       // The former is 2 bytes shorter. In case where the increment is 1, then
664       // the saving can be 4 bytes (by using incl %eax).
665       if (auto *Imm = dyn_cast<ConstantSDNode>(Op1)) {
666         if (Imm->getAPIntValue().isSignedIntN(8))
667           return false;
668 
669         // If this is a 64-bit AND with an immediate that fits in 32-bits,
670         // prefer using the smaller and over folding the load. This is needed to
671         // make sure immediates created by shrinkAndImmediate are always folded.
672         // Ideally we would narrow the load during DAG combine and get the
673         // best of both worlds.
674         if (U->getOpcode() == ISD::AND &&
675             Imm->getAPIntValue().getBitWidth() == 64 &&
676             Imm->getAPIntValue().isIntN(32))
677           return false;
678 
679         // If this really a zext_inreg that can be represented with a movzx
680         // instruction, prefer that.
681         // TODO: We could shrink the load and fold if it is non-volatile.
682         if (U->getOpcode() == ISD::AND &&
683             (Imm->getAPIntValue() == UINT8_MAX ||
684              Imm->getAPIntValue() == UINT16_MAX ||
685              Imm->getAPIntValue() == UINT32_MAX))
686           return false;
687 
688         // ADD/SUB with can negate the immediate and use the opposite operation
689         // to fit 128 into a sign extended 8 bit immediate.
690         if ((U->getOpcode() == ISD::ADD || U->getOpcode() == ISD::SUB) &&
691             (-Imm->getAPIntValue()).isSignedIntN(8))
692           return false;
693 
694         if ((U->getOpcode() == X86ISD::ADD || U->getOpcode() == X86ISD::SUB) &&
695             (-Imm->getAPIntValue()).isSignedIntN(8) &&
696             hasNoCarryFlagUses(SDValue(U, 1)))
697           return false;
698       }
699 
700       // If the other operand is a TLS address, we should fold it instead.
701       // This produces
702       // movl    %gs:0, %eax
703       // leal    i@NTPOFF(%eax), %eax
704       // instead of
705       // movl    $i@NTPOFF, %eax
706       // addl    %gs:0, %eax
707       // if the block also has an access to a second TLS address this will save
708       // a load.
709       // FIXME: This is probably also true for non-TLS addresses.
710       if (Op1.getOpcode() == X86ISD::Wrapper) {
711         SDValue Val = Op1.getOperand(0);
712         if (Val.getOpcode() == ISD::TargetGlobalTLSAddress)
713           return false;
714       }
715 
716       // Don't fold load if this matches the BTS/BTR/BTC patterns.
717       // BTS: (or X, (shl 1, n))
718       // BTR: (and X, (rotl -2, n))
719       // BTC: (xor X, (shl 1, n))
720       if (U->getOpcode() == ISD::OR || U->getOpcode() == ISD::XOR) {
721         if (U->getOperand(0).getOpcode() == ISD::SHL &&
722             isOneConstant(U->getOperand(0).getOperand(0)))
723           return false;
724 
725         if (U->getOperand(1).getOpcode() == ISD::SHL &&
726             isOneConstant(U->getOperand(1).getOperand(0)))
727           return false;
728       }
729       if (U->getOpcode() == ISD::AND) {
730         SDValue U0 = U->getOperand(0);
731         SDValue U1 = U->getOperand(1);
732         if (U0.getOpcode() == ISD::ROTL) {
733           auto *C = dyn_cast<ConstantSDNode>(U0.getOperand(0));
734           if (C && C->getSExtValue() == -2)
735             return false;
736         }
737 
738         if (U1.getOpcode() == ISD::ROTL) {
739           auto *C = dyn_cast<ConstantSDNode>(U1.getOperand(0));
740           if (C && C->getSExtValue() == -2)
741             return false;
742         }
743       }
744 
745       break;
746     }
747     case ISD::SHL:
748     case ISD::SRA:
749     case ISD::SRL:
750       // Don't fold a load into a shift by immediate. The BMI2 instructions
751       // support folding a load, but not an immediate. The legacy instructions
752       // support folding an immediate, but can't fold a load. Folding an
753       // immediate is preferable to folding a load.
754       if (isa<ConstantSDNode>(U->getOperand(1)))
755         return false;
756 
757       break;
758     }
759   }
760 
761   // Prevent folding a load if this can implemented with an insert_subreg or
762   // a move that implicitly zeroes.
763   if (Root->getOpcode() == ISD::INSERT_SUBVECTOR &&
764       isNullConstant(Root->getOperand(2)) &&
765       (Root->getOperand(0).isUndef() ||
766        ISD::isBuildVectorAllZeros(Root->getOperand(0).getNode())))
767     return false;
768 
769   return true;
770 }
771 
772 // Indicates it is profitable to form an AVX512 masked operation. Returning
773 // false will favor a masked register-register masked move or vblendm and the
774 // operation will be selected separately.
775 bool X86DAGToDAGISel::isProfitableToFormMaskedOp(SDNode *N) const {
776   assert(
777       (N->getOpcode() == ISD::VSELECT || N->getOpcode() == X86ISD::SELECTS) &&
778       "Unexpected opcode!");
779 
780   // If the operation has additional users, the operation will be duplicated.
781   // Check the use count to prevent that.
782   // FIXME: Are there cheap opcodes we might want to duplicate?
783   return N->getOperand(1).hasOneUse();
784 }
785 
786 /// Replace the original chain operand of the call with
787 /// load's chain operand and move load below the call's chain operand.
788 static void moveBelowOrigChain(SelectionDAG *CurDAG, SDValue Load,
789                                SDValue Call, SDValue OrigChain) {
790   SmallVector<SDValue, 8> Ops;
791   SDValue Chain = OrigChain.getOperand(0);
792   if (Chain.getNode() == Load.getNode())
793     Ops.push_back(Load.getOperand(0));
794   else {
795     assert(Chain.getOpcode() == ISD::TokenFactor &&
796            "Unexpected chain operand");
797     for (unsigned i = 0, e = Chain.getNumOperands(); i != e; ++i)
798       if (Chain.getOperand(i).getNode() == Load.getNode())
799         Ops.push_back(Load.getOperand(0));
800       else
801         Ops.push_back(Chain.getOperand(i));
802     SDValue NewChain =
803       CurDAG->getNode(ISD::TokenFactor, SDLoc(Load), MVT::Other, Ops);
804     Ops.clear();
805     Ops.push_back(NewChain);
806   }
807   Ops.append(OrigChain->op_begin() + 1, OrigChain->op_end());
808   CurDAG->UpdateNodeOperands(OrigChain.getNode(), Ops);
809   CurDAG->UpdateNodeOperands(Load.getNode(), Call.getOperand(0),
810                              Load.getOperand(1), Load.getOperand(2));
811 
812   Ops.clear();
813   Ops.push_back(SDValue(Load.getNode(), 1));
814   Ops.append(Call->op_begin() + 1, Call->op_end());
815   CurDAG->UpdateNodeOperands(Call.getNode(), Ops);
816 }
817 
818 /// Return true if call address is a load and it can be
819 /// moved below CALLSEQ_START and the chains leading up to the call.
820 /// Return the CALLSEQ_START by reference as a second output.
821 /// In the case of a tail call, there isn't a callseq node between the call
822 /// chain and the load.
823 static bool isCalleeLoad(SDValue Callee, SDValue &Chain, bool HasCallSeq) {
824   // The transformation is somewhat dangerous if the call's chain was glued to
825   // the call. After MoveBelowOrigChain the load is moved between the call and
826   // the chain, this can create a cycle if the load is not folded. So it is
827   // *really* important that we are sure the load will be folded.
828   if (Callee.getNode() == Chain.getNode() || !Callee.hasOneUse())
829     return false;
830   auto *LD = dyn_cast<LoadSDNode>(Callee.getNode());
831   if (!LD ||
832       !LD->isSimple() ||
833       LD->getAddressingMode() != ISD::UNINDEXED ||
834       LD->getExtensionType() != ISD::NON_EXTLOAD)
835     return false;
836 
837   // Now let's find the callseq_start.
838   while (HasCallSeq && Chain.getOpcode() != ISD::CALLSEQ_START) {
839     if (!Chain.hasOneUse())
840       return false;
841     Chain = Chain.getOperand(0);
842   }
843 
844   if (!Chain.getNumOperands())
845     return false;
846   // Since we are not checking for AA here, conservatively abort if the chain
847   // writes to memory. It's not safe to move the callee (a load) across a store.
848   if (isa<MemSDNode>(Chain.getNode()) &&
849       cast<MemSDNode>(Chain.getNode())->writeMem())
850     return false;
851   if (Chain.getOperand(0).getNode() == Callee.getNode())
852     return true;
853   if (Chain.getOperand(0).getOpcode() == ISD::TokenFactor &&
854       Callee.getValue(1).isOperandOf(Chain.getOperand(0).getNode()) &&
855       Callee.getValue(1).hasOneUse())
856     return true;
857   return false;
858 }
859 
860 static bool isEndbrImm64(uint64_t Imm) {
861 // There may be some other prefix bytes between 0xF3 and 0x0F1EFA.
862 // i.g: 0xF3660F1EFA, 0xF3670F1EFA
863   if ((Imm & 0x00FFFFFF) != 0x0F1EFA)
864     return false;
865 
866   uint8_t OptionalPrefixBytes [] = {0x26, 0x2e, 0x36, 0x3e, 0x64,
867                                     0x65, 0x66, 0x67, 0xf0, 0xf2};
868   int i = 24; // 24bit 0x0F1EFA has matched
869   while (i < 64) {
870     uint8_t Byte = (Imm >> i) & 0xFF;
871     if (Byte == 0xF3)
872       return true;
873     if (!llvm::is_contained(OptionalPrefixBytes, Byte))
874       return false;
875     i += 8;
876   }
877 
878   return false;
879 }
880 
881 void X86DAGToDAGISel::PreprocessISelDAG() {
882   bool MadeChange = false;
883   for (SelectionDAG::allnodes_iterator I = CurDAG->allnodes_begin(),
884        E = CurDAG->allnodes_end(); I != E; ) {
885     SDNode *N = &*I++; // Preincrement iterator to avoid invalidation issues.
886 
887     // This is for CET enhancement.
888     //
889     // ENDBR32 and ENDBR64 have specific opcodes:
890     // ENDBR32: F3 0F 1E FB
891     // ENDBR64: F3 0F 1E FA
892     // And we want that attackers won’t find unintended ENDBR32/64
893     // opcode matches in the binary
894     // Here’s an example:
895     // If the compiler had to generate asm for the following code:
896     // a = 0xF30F1EFA
897     // it could, for example, generate:
898     // mov 0xF30F1EFA, dword ptr[a]
899     // In such a case, the binary would include a gadget that starts
900     // with a fake ENDBR64 opcode. Therefore, we split such generation
901     // into multiple operations, let it not shows in the binary
902     if (N->getOpcode() == ISD::Constant) {
903       MVT VT = N->getSimpleValueType(0);
904       int64_t Imm = cast<ConstantSDNode>(N)->getSExtValue();
905       int32_t EndbrImm = Subtarget->is64Bit() ? 0xF30F1EFA : 0xF30F1EFB;
906       if (Imm == EndbrImm || isEndbrImm64(Imm)) {
907         // Check that the cf-protection-branch is enabled.
908         Metadata *CFProtectionBranch =
909           MF->getMMI().getModule()->getModuleFlag("cf-protection-branch");
910         if (CFProtectionBranch || IndirectBranchTracking) {
911           SDLoc dl(N);
912           SDValue Complement = CurDAG->getConstant(~Imm, dl, VT, false, true);
913           Complement = CurDAG->getNOT(dl, Complement, VT);
914           --I;
915           CurDAG->ReplaceAllUsesOfValueWith(SDValue(N, 0), Complement);
916           ++I;
917           MadeChange = true;
918           continue;
919         }
920       }
921     }
922 
923     // If this is a target specific AND node with no flag usages, turn it back
924     // into ISD::AND to enable test instruction matching.
925     if (N->getOpcode() == X86ISD::AND && !N->hasAnyUseOfValue(1)) {
926       SDValue Res = CurDAG->getNode(ISD::AND, SDLoc(N), N->getValueType(0),
927                                     N->getOperand(0), N->getOperand(1));
928       --I;
929       CurDAG->ReplaceAllUsesOfValueWith(SDValue(N, 0), Res);
930       ++I;
931       MadeChange = true;
932       continue;
933     }
934 
935     // Convert vector increment or decrement to sub/add with an all-ones
936     // constant:
937     // add X, <1, 1...> --> sub X, <-1, -1...>
938     // sub X, <1, 1...> --> add X, <-1, -1...>
939     // The all-ones vector constant can be materialized using a pcmpeq
940     // instruction that is commonly recognized as an idiom (has no register
941     // dependency), so that's better/smaller than loading a splat 1 constant.
942     //
943     // But don't do this if it would inhibit a potentially profitable load
944     // folding opportunity for the other operand. That only occurs with the
945     // intersection of:
946     // (1) The other operand (op0) is load foldable.
947     // (2) The op is an add (otherwise, we are *creating* an add and can still
948     //     load fold the other op).
949     // (3) The target has AVX (otherwise, we have a destructive add and can't
950     //     load fold the other op without killing the constant op).
951     // (4) The constant 1 vector has multiple uses (so it is profitable to load
952     //     into a register anyway).
953     auto mayPreventLoadFold = [&]() {
954       return X86::mayFoldLoad(N->getOperand(0), *Subtarget) &&
955              N->getOpcode() == ISD::ADD && Subtarget->hasAVX() &&
956              !N->getOperand(1).hasOneUse();
957     };
958     if ((N->getOpcode() == ISD::ADD || N->getOpcode() == ISD::SUB) &&
959         N->getSimpleValueType(0).isVector() && !mayPreventLoadFold()) {
960       APInt SplatVal;
961       if (X86::isConstantSplat(N->getOperand(1), SplatVal) &&
962           SplatVal.isOne()) {
963         SDLoc DL(N);
964 
965         MVT VT = N->getSimpleValueType(0);
966         unsigned NumElts = VT.getSizeInBits() / 32;
967         SDValue AllOnes =
968             CurDAG->getAllOnesConstant(DL, MVT::getVectorVT(MVT::i32, NumElts));
969         AllOnes = CurDAG->getBitcast(VT, AllOnes);
970 
971         unsigned NewOpcode = N->getOpcode() == ISD::ADD ? ISD::SUB : ISD::ADD;
972         SDValue Res =
973             CurDAG->getNode(NewOpcode, DL, VT, N->getOperand(0), AllOnes);
974         --I;
975         CurDAG->ReplaceAllUsesWith(N, Res.getNode());
976         ++I;
977         MadeChange = true;
978         continue;
979       }
980     }
981 
982     switch (N->getOpcode()) {
983     case X86ISD::VBROADCAST: {
984       MVT VT = N->getSimpleValueType(0);
985       // Emulate v32i16/v64i8 broadcast without BWI.
986       if (!Subtarget->hasBWI() && (VT == MVT::v32i16 || VT == MVT::v64i8)) {
987         MVT NarrowVT = VT == MVT::v32i16 ? MVT::v16i16 : MVT::v32i8;
988         SDLoc dl(N);
989         SDValue NarrowBCast =
990             CurDAG->getNode(X86ISD::VBROADCAST, dl, NarrowVT, N->getOperand(0));
991         SDValue Res =
992             CurDAG->getNode(ISD::INSERT_SUBVECTOR, dl, VT, CurDAG->getUNDEF(VT),
993                             NarrowBCast, CurDAG->getIntPtrConstant(0, dl));
994         unsigned Index = VT == MVT::v32i16 ? 16 : 32;
995         Res = CurDAG->getNode(ISD::INSERT_SUBVECTOR, dl, VT, Res, NarrowBCast,
996                               CurDAG->getIntPtrConstant(Index, dl));
997 
998         --I;
999         CurDAG->ReplaceAllUsesWith(N, Res.getNode());
1000         ++I;
1001         MadeChange = true;
1002         continue;
1003       }
1004 
1005       break;
1006     }
1007     case X86ISD::VBROADCAST_LOAD: {
1008       MVT VT = N->getSimpleValueType(0);
1009       // Emulate v32i16/v64i8 broadcast without BWI.
1010       if (!Subtarget->hasBWI() && (VT == MVT::v32i16 || VT == MVT::v64i8)) {
1011         MVT NarrowVT = VT == MVT::v32i16 ? MVT::v16i16 : MVT::v32i8;
1012         auto *MemNode = cast<MemSDNode>(N);
1013         SDLoc dl(N);
1014         SDVTList VTs = CurDAG->getVTList(NarrowVT, MVT::Other);
1015         SDValue Ops[] = {MemNode->getChain(), MemNode->getBasePtr()};
1016         SDValue NarrowBCast = CurDAG->getMemIntrinsicNode(
1017             X86ISD::VBROADCAST_LOAD, dl, VTs, Ops, MemNode->getMemoryVT(),
1018             MemNode->getMemOperand());
1019         SDValue Res =
1020             CurDAG->getNode(ISD::INSERT_SUBVECTOR, dl, VT, CurDAG->getUNDEF(VT),
1021                             NarrowBCast, CurDAG->getIntPtrConstant(0, dl));
1022         unsigned Index = VT == MVT::v32i16 ? 16 : 32;
1023         Res = CurDAG->getNode(ISD::INSERT_SUBVECTOR, dl, VT, Res, NarrowBCast,
1024                               CurDAG->getIntPtrConstant(Index, dl));
1025 
1026         --I;
1027         SDValue To[] = {Res, NarrowBCast.getValue(1)};
1028         CurDAG->ReplaceAllUsesWith(N, To);
1029         ++I;
1030         MadeChange = true;
1031         continue;
1032       }
1033 
1034       break;
1035     }
1036     case ISD::VSELECT: {
1037       // Replace VSELECT with non-mask conditions with with BLENDV/VPTERNLOG.
1038       EVT EleVT = N->getOperand(0).getValueType().getVectorElementType();
1039       if (EleVT == MVT::i1)
1040         break;
1041 
1042       assert(Subtarget->hasSSE41() && "Expected SSE4.1 support!");
1043       assert(N->getValueType(0).getVectorElementType() != MVT::i16 &&
1044              "We can't replace VSELECT with BLENDV in vXi16!");
1045       SDValue R;
1046       if (Subtarget->hasVLX() && CurDAG->ComputeNumSignBits(N->getOperand(0)) ==
1047                                      EleVT.getSizeInBits()) {
1048         R = CurDAG->getNode(X86ISD::VPTERNLOG, SDLoc(N), N->getValueType(0),
1049                             N->getOperand(0), N->getOperand(1), N->getOperand(2),
1050                             CurDAG->getTargetConstant(0xCA, SDLoc(N), MVT::i8));
1051       } else {
1052         R = CurDAG->getNode(X86ISD::BLENDV, SDLoc(N), N->getValueType(0),
1053                             N->getOperand(0), N->getOperand(1),
1054                             N->getOperand(2));
1055       }
1056       --I;
1057       CurDAG->ReplaceAllUsesWith(N, R.getNode());
1058       ++I;
1059       MadeChange = true;
1060       continue;
1061     }
1062     case ISD::FP_ROUND:
1063     case ISD::STRICT_FP_ROUND:
1064     case ISD::FP_TO_SINT:
1065     case ISD::FP_TO_UINT:
1066     case ISD::STRICT_FP_TO_SINT:
1067     case ISD::STRICT_FP_TO_UINT: {
1068       // Replace vector fp_to_s/uint with their X86 specific equivalent so we
1069       // don't need 2 sets of patterns.
1070       if (!N->getSimpleValueType(0).isVector())
1071         break;
1072 
1073       unsigned NewOpc;
1074       switch (N->getOpcode()) {
1075       default: llvm_unreachable("Unexpected opcode!");
1076       case ISD::FP_ROUND:          NewOpc = X86ISD::VFPROUND;        break;
1077       case ISD::STRICT_FP_ROUND:   NewOpc = X86ISD::STRICT_VFPROUND; break;
1078       case ISD::STRICT_FP_TO_SINT: NewOpc = X86ISD::STRICT_CVTTP2SI; break;
1079       case ISD::FP_TO_SINT:        NewOpc = X86ISD::CVTTP2SI;        break;
1080       case ISD::STRICT_FP_TO_UINT: NewOpc = X86ISD::STRICT_CVTTP2UI; break;
1081       case ISD::FP_TO_UINT:        NewOpc = X86ISD::CVTTP2UI;        break;
1082       }
1083       SDValue Res;
1084       if (N->isStrictFPOpcode())
1085         Res =
1086             CurDAG->getNode(NewOpc, SDLoc(N), {N->getValueType(0), MVT::Other},
1087                             {N->getOperand(0), N->getOperand(1)});
1088       else
1089         Res =
1090             CurDAG->getNode(NewOpc, SDLoc(N), N->getValueType(0),
1091                             N->getOperand(0));
1092       --I;
1093       CurDAG->ReplaceAllUsesWith(N, Res.getNode());
1094       ++I;
1095       MadeChange = true;
1096       continue;
1097     }
1098     case ISD::SHL:
1099     case ISD::SRA:
1100     case ISD::SRL: {
1101       // Replace vector shifts with their X86 specific equivalent so we don't
1102       // need 2 sets of patterns.
1103       if (!N->getValueType(0).isVector())
1104         break;
1105 
1106       unsigned NewOpc;
1107       switch (N->getOpcode()) {
1108       default: llvm_unreachable("Unexpected opcode!");
1109       case ISD::SHL: NewOpc = X86ISD::VSHLV; break;
1110       case ISD::SRA: NewOpc = X86ISD::VSRAV; break;
1111       case ISD::SRL: NewOpc = X86ISD::VSRLV; break;
1112       }
1113       SDValue Res = CurDAG->getNode(NewOpc, SDLoc(N), N->getValueType(0),
1114                                     N->getOperand(0), N->getOperand(1));
1115       --I;
1116       CurDAG->ReplaceAllUsesOfValueWith(SDValue(N, 0), Res);
1117       ++I;
1118       MadeChange = true;
1119       continue;
1120     }
1121     case ISD::ANY_EXTEND:
1122     case ISD::ANY_EXTEND_VECTOR_INREG: {
1123       // Replace vector any extend with the zero extend equivalents so we don't
1124       // need 2 sets of patterns. Ignore vXi1 extensions.
1125       if (!N->getValueType(0).isVector())
1126         break;
1127 
1128       unsigned NewOpc;
1129       if (N->getOperand(0).getScalarValueSizeInBits() == 1) {
1130         assert(N->getOpcode() == ISD::ANY_EXTEND &&
1131                "Unexpected opcode for mask vector!");
1132         NewOpc = ISD::SIGN_EXTEND;
1133       } else {
1134         NewOpc = N->getOpcode() == ISD::ANY_EXTEND
1135                               ? ISD::ZERO_EXTEND
1136                               : ISD::ZERO_EXTEND_VECTOR_INREG;
1137       }
1138 
1139       SDValue Res = CurDAG->getNode(NewOpc, SDLoc(N), N->getValueType(0),
1140                                     N->getOperand(0));
1141       --I;
1142       CurDAG->ReplaceAllUsesOfValueWith(SDValue(N, 0), Res);
1143       ++I;
1144       MadeChange = true;
1145       continue;
1146     }
1147     case ISD::FCEIL:
1148     case ISD::STRICT_FCEIL:
1149     case ISD::FFLOOR:
1150     case ISD::STRICT_FFLOOR:
1151     case ISD::FTRUNC:
1152     case ISD::STRICT_FTRUNC:
1153     case ISD::FROUNDEVEN:
1154     case ISD::STRICT_FROUNDEVEN:
1155     case ISD::FNEARBYINT:
1156     case ISD::STRICT_FNEARBYINT:
1157     case ISD::FRINT:
1158     case ISD::STRICT_FRINT: {
1159       // Replace fp rounding with their X86 specific equivalent so we don't
1160       // need 2 sets of patterns.
1161       unsigned Imm;
1162       switch (N->getOpcode()) {
1163       default: llvm_unreachable("Unexpected opcode!");
1164       case ISD::STRICT_FCEIL:
1165       case ISD::FCEIL:      Imm = 0xA; break;
1166       case ISD::STRICT_FFLOOR:
1167       case ISD::FFLOOR:     Imm = 0x9; break;
1168       case ISD::STRICT_FTRUNC:
1169       case ISD::FTRUNC:     Imm = 0xB; break;
1170       case ISD::STRICT_FROUNDEVEN:
1171       case ISD::FROUNDEVEN: Imm = 0x8; break;
1172       case ISD::STRICT_FNEARBYINT:
1173       case ISD::FNEARBYINT: Imm = 0xC; break;
1174       case ISD::STRICT_FRINT:
1175       case ISD::FRINT:      Imm = 0x4; break;
1176       }
1177       SDLoc dl(N);
1178       bool IsStrict = N->isStrictFPOpcode();
1179       SDValue Res;
1180       if (IsStrict)
1181         Res = CurDAG->getNode(X86ISD::STRICT_VRNDSCALE, dl,
1182                               {N->getValueType(0), MVT::Other},
1183                               {N->getOperand(0), N->getOperand(1),
1184                                CurDAG->getTargetConstant(Imm, dl, MVT::i32)});
1185       else
1186         Res = CurDAG->getNode(X86ISD::VRNDSCALE, dl, N->getValueType(0),
1187                               N->getOperand(0),
1188                               CurDAG->getTargetConstant(Imm, dl, MVT::i32));
1189       --I;
1190       CurDAG->ReplaceAllUsesWith(N, Res.getNode());
1191       ++I;
1192       MadeChange = true;
1193       continue;
1194     }
1195     case X86ISD::FANDN:
1196     case X86ISD::FAND:
1197     case X86ISD::FOR:
1198     case X86ISD::FXOR: {
1199       // Widen scalar fp logic ops to vector to reduce isel patterns.
1200       // FIXME: Can we do this during lowering/combine.
1201       MVT VT = N->getSimpleValueType(0);
1202       if (VT.isVector() || VT == MVT::f128)
1203         break;
1204 
1205       MVT VecVT = VT == MVT::f64   ? MVT::v2f64
1206                   : VT == MVT::f32 ? MVT::v4f32
1207                                    : MVT::v8f16;
1208 
1209       SDLoc dl(N);
1210       SDValue Op0 = CurDAG->getNode(ISD::SCALAR_TO_VECTOR, dl, VecVT,
1211                                     N->getOperand(0));
1212       SDValue Op1 = CurDAG->getNode(ISD::SCALAR_TO_VECTOR, dl, VecVT,
1213                                     N->getOperand(1));
1214 
1215       SDValue Res;
1216       if (Subtarget->hasSSE2()) {
1217         EVT IntVT = EVT(VecVT).changeVectorElementTypeToInteger();
1218         Op0 = CurDAG->getNode(ISD::BITCAST, dl, IntVT, Op0);
1219         Op1 = CurDAG->getNode(ISD::BITCAST, dl, IntVT, Op1);
1220         unsigned Opc;
1221         switch (N->getOpcode()) {
1222         default: llvm_unreachable("Unexpected opcode!");
1223         case X86ISD::FANDN: Opc = X86ISD::ANDNP; break;
1224         case X86ISD::FAND:  Opc = ISD::AND;      break;
1225         case X86ISD::FOR:   Opc = ISD::OR;       break;
1226         case X86ISD::FXOR:  Opc = ISD::XOR;      break;
1227         }
1228         Res = CurDAG->getNode(Opc, dl, IntVT, Op0, Op1);
1229         Res = CurDAG->getNode(ISD::BITCAST, dl, VecVT, Res);
1230       } else {
1231         Res = CurDAG->getNode(N->getOpcode(), dl, VecVT, Op0, Op1);
1232       }
1233       Res = CurDAG->getNode(ISD::EXTRACT_VECTOR_ELT, dl, VT, Res,
1234                             CurDAG->getIntPtrConstant(0, dl));
1235       --I;
1236       CurDAG->ReplaceAllUsesOfValueWith(SDValue(N, 0), Res);
1237       ++I;
1238       MadeChange = true;
1239       continue;
1240     }
1241     }
1242 
1243     if (OptLevel != CodeGenOpt::None &&
1244         // Only do this when the target can fold the load into the call or
1245         // jmp.
1246         !Subtarget->useIndirectThunkCalls() &&
1247         ((N->getOpcode() == X86ISD::CALL && !Subtarget->slowTwoMemOps()) ||
1248          (N->getOpcode() == X86ISD::TC_RETURN &&
1249           (Subtarget->is64Bit() ||
1250            !getTargetMachine().isPositionIndependent())))) {
1251       /// Also try moving call address load from outside callseq_start to just
1252       /// before the call to allow it to be folded.
1253       ///
1254       ///     [Load chain]
1255       ///         ^
1256       ///         |
1257       ///       [Load]
1258       ///       ^    ^
1259       ///       |    |
1260       ///      /      \--
1261       ///     /          |
1262       ///[CALLSEQ_START] |
1263       ///     ^          |
1264       ///     |          |
1265       /// [LOAD/C2Reg]   |
1266       ///     |          |
1267       ///      \        /
1268       ///       \      /
1269       ///       [CALL]
1270       bool HasCallSeq = N->getOpcode() == X86ISD::CALL;
1271       SDValue Chain = N->getOperand(0);
1272       SDValue Load  = N->getOperand(1);
1273       if (!isCalleeLoad(Load, Chain, HasCallSeq))
1274         continue;
1275       moveBelowOrigChain(CurDAG, Load, SDValue(N, 0), Chain);
1276       ++NumLoadMoved;
1277       MadeChange = true;
1278       continue;
1279     }
1280 
1281     // Lower fpround and fpextend nodes that target the FP stack to be store and
1282     // load to the stack.  This is a gross hack.  We would like to simply mark
1283     // these as being illegal, but when we do that, legalize produces these when
1284     // it expands calls, then expands these in the same legalize pass.  We would
1285     // like dag combine to be able to hack on these between the call expansion
1286     // and the node legalization.  As such this pass basically does "really
1287     // late" legalization of these inline with the X86 isel pass.
1288     // FIXME: This should only happen when not compiled with -O0.
1289     switch (N->getOpcode()) {
1290     default: continue;
1291     case ISD::FP_ROUND:
1292     case ISD::FP_EXTEND:
1293     {
1294       MVT SrcVT = N->getOperand(0).getSimpleValueType();
1295       MVT DstVT = N->getSimpleValueType(0);
1296 
1297       // If any of the sources are vectors, no fp stack involved.
1298       if (SrcVT.isVector() || DstVT.isVector())
1299         continue;
1300 
1301       // If the source and destination are SSE registers, then this is a legal
1302       // conversion that should not be lowered.
1303       const X86TargetLowering *X86Lowering =
1304           static_cast<const X86TargetLowering *>(TLI);
1305       bool SrcIsSSE = X86Lowering->isScalarFPTypeInSSEReg(SrcVT);
1306       bool DstIsSSE = X86Lowering->isScalarFPTypeInSSEReg(DstVT);
1307       if (SrcIsSSE && DstIsSSE)
1308         continue;
1309 
1310       if (!SrcIsSSE && !DstIsSSE) {
1311         // If this is an FPStack extension, it is a noop.
1312         if (N->getOpcode() == ISD::FP_EXTEND)
1313           continue;
1314         // If this is a value-preserving FPStack truncation, it is a noop.
1315         if (N->getConstantOperandVal(1))
1316           continue;
1317       }
1318 
1319       // Here we could have an FP stack truncation or an FPStack <-> SSE convert.
1320       // FPStack has extload and truncstore.  SSE can fold direct loads into other
1321       // operations.  Based on this, decide what we want to do.
1322       MVT MemVT = (N->getOpcode() == ISD::FP_ROUND) ? DstVT : SrcVT;
1323       SDValue MemTmp = CurDAG->CreateStackTemporary(MemVT);
1324       int SPFI = cast<FrameIndexSDNode>(MemTmp)->getIndex();
1325       MachinePointerInfo MPI =
1326           MachinePointerInfo::getFixedStack(CurDAG->getMachineFunction(), SPFI);
1327       SDLoc dl(N);
1328 
1329       // FIXME: optimize the case where the src/dest is a load or store?
1330 
1331       SDValue Store = CurDAG->getTruncStore(
1332           CurDAG->getEntryNode(), dl, N->getOperand(0), MemTmp, MPI, MemVT);
1333       SDValue Result = CurDAG->getExtLoad(ISD::EXTLOAD, dl, DstVT, Store,
1334                                           MemTmp, MPI, MemVT);
1335 
1336       // We're about to replace all uses of the FP_ROUND/FP_EXTEND with the
1337       // extload we created.  This will cause general havok on the dag because
1338       // anything below the conversion could be folded into other existing nodes.
1339       // To avoid invalidating 'I', back it up to the convert node.
1340       --I;
1341       CurDAG->ReplaceAllUsesOfValueWith(SDValue(N, 0), Result);
1342       break;
1343     }
1344 
1345     //The sequence of events for lowering STRICT_FP versions of these nodes requires
1346     //dealing with the chain differently, as there is already a preexisting chain.
1347     case ISD::STRICT_FP_ROUND:
1348     case ISD::STRICT_FP_EXTEND:
1349     {
1350       MVT SrcVT = N->getOperand(1).getSimpleValueType();
1351       MVT DstVT = N->getSimpleValueType(0);
1352 
1353       // If any of the sources are vectors, no fp stack involved.
1354       if (SrcVT.isVector() || DstVT.isVector())
1355         continue;
1356 
1357       // If the source and destination are SSE registers, then this is a legal
1358       // conversion that should not be lowered.
1359       const X86TargetLowering *X86Lowering =
1360           static_cast<const X86TargetLowering *>(TLI);
1361       bool SrcIsSSE = X86Lowering->isScalarFPTypeInSSEReg(SrcVT);
1362       bool DstIsSSE = X86Lowering->isScalarFPTypeInSSEReg(DstVT);
1363       if (SrcIsSSE && DstIsSSE)
1364         continue;
1365 
1366       if (!SrcIsSSE && !DstIsSSE) {
1367         // If this is an FPStack extension, it is a noop.
1368         if (N->getOpcode() == ISD::STRICT_FP_EXTEND)
1369           continue;
1370         // If this is a value-preserving FPStack truncation, it is a noop.
1371         if (N->getConstantOperandVal(2))
1372           continue;
1373       }
1374 
1375       // Here we could have an FP stack truncation or an FPStack <-> SSE convert.
1376       // FPStack has extload and truncstore.  SSE can fold direct loads into other
1377       // operations.  Based on this, decide what we want to do.
1378       MVT MemVT = (N->getOpcode() == ISD::STRICT_FP_ROUND) ? DstVT : SrcVT;
1379       SDValue MemTmp = CurDAG->CreateStackTemporary(MemVT);
1380       int SPFI = cast<FrameIndexSDNode>(MemTmp)->getIndex();
1381       MachinePointerInfo MPI =
1382           MachinePointerInfo::getFixedStack(CurDAG->getMachineFunction(), SPFI);
1383       SDLoc dl(N);
1384 
1385       // FIXME: optimize the case where the src/dest is a load or store?
1386 
1387       //Since the operation is StrictFP, use the preexisting chain.
1388       SDValue Store, Result;
1389       if (!SrcIsSSE) {
1390         SDVTList VTs = CurDAG->getVTList(MVT::Other);
1391         SDValue Ops[] = {N->getOperand(0), N->getOperand(1), MemTmp};
1392         Store = CurDAG->getMemIntrinsicNode(X86ISD::FST, dl, VTs, Ops, MemVT,
1393                                             MPI, /*Align*/ std::nullopt,
1394                                             MachineMemOperand::MOStore);
1395         if (N->getFlags().hasNoFPExcept()) {
1396           SDNodeFlags Flags = Store->getFlags();
1397           Flags.setNoFPExcept(true);
1398           Store->setFlags(Flags);
1399         }
1400       } else {
1401         assert(SrcVT == MemVT && "Unexpected VT!");
1402         Store = CurDAG->getStore(N->getOperand(0), dl, N->getOperand(1), MemTmp,
1403                                  MPI);
1404       }
1405 
1406       if (!DstIsSSE) {
1407         SDVTList VTs = CurDAG->getVTList(DstVT, MVT::Other);
1408         SDValue Ops[] = {Store, MemTmp};
1409         Result = CurDAG->getMemIntrinsicNode(
1410             X86ISD::FLD, dl, VTs, Ops, MemVT, MPI,
1411             /*Align*/ std::nullopt, MachineMemOperand::MOLoad);
1412         if (N->getFlags().hasNoFPExcept()) {
1413           SDNodeFlags Flags = Result->getFlags();
1414           Flags.setNoFPExcept(true);
1415           Result->setFlags(Flags);
1416         }
1417       } else {
1418         assert(DstVT == MemVT && "Unexpected VT!");
1419         Result = CurDAG->getLoad(DstVT, dl, Store, MemTmp, MPI);
1420       }
1421 
1422       // We're about to replace all uses of the FP_ROUND/FP_EXTEND with the
1423       // extload we created.  This will cause general havok on the dag because
1424       // anything below the conversion could be folded into other existing nodes.
1425       // To avoid invalidating 'I', back it up to the convert node.
1426       --I;
1427       CurDAG->ReplaceAllUsesWith(N, Result.getNode());
1428       break;
1429     }
1430     }
1431 
1432 
1433     // Now that we did that, the node is dead.  Increment the iterator to the
1434     // next node to process, then delete N.
1435     ++I;
1436     MadeChange = true;
1437   }
1438 
1439   // Remove any dead nodes that may have been left behind.
1440   if (MadeChange)
1441     CurDAG->RemoveDeadNodes();
1442 }
1443 
1444 // Look for a redundant movzx/movsx that can occur after an 8-bit divrem.
1445 bool X86DAGToDAGISel::tryOptimizeRem8Extend(SDNode *N) {
1446   unsigned Opc = N->getMachineOpcode();
1447   if (Opc != X86::MOVZX32rr8 && Opc != X86::MOVSX32rr8 &&
1448       Opc != X86::MOVSX64rr8)
1449     return false;
1450 
1451   SDValue N0 = N->getOperand(0);
1452 
1453   // We need to be extracting the lower bit of an extend.
1454   if (!N0.isMachineOpcode() ||
1455       N0.getMachineOpcode() != TargetOpcode::EXTRACT_SUBREG ||
1456       N0.getConstantOperandVal(1) != X86::sub_8bit)
1457     return false;
1458 
1459   // We're looking for either a movsx or movzx to match the original opcode.
1460   unsigned ExpectedOpc = Opc == X86::MOVZX32rr8 ? X86::MOVZX32rr8_NOREX
1461                                                 : X86::MOVSX32rr8_NOREX;
1462   SDValue N00 = N0.getOperand(0);
1463   if (!N00.isMachineOpcode() || N00.getMachineOpcode() != ExpectedOpc)
1464     return false;
1465 
1466   if (Opc == X86::MOVSX64rr8) {
1467     // If we had a sign extend from 8 to 64 bits. We still need to go from 32
1468     // to 64.
1469     MachineSDNode *Extend = CurDAG->getMachineNode(X86::MOVSX64rr32, SDLoc(N),
1470                                                    MVT::i64, N00);
1471     ReplaceUses(N, Extend);
1472   } else {
1473     // Ok we can drop this extend and just use the original extend.
1474     ReplaceUses(N, N00.getNode());
1475   }
1476 
1477   return true;
1478 }
1479 
1480 void X86DAGToDAGISel::PostprocessISelDAG() {
1481   // Skip peepholes at -O0.
1482   if (TM.getOptLevel() == CodeGenOpt::None)
1483     return;
1484 
1485   SelectionDAG::allnodes_iterator Position = CurDAG->allnodes_end();
1486 
1487   bool MadeChange = false;
1488   while (Position != CurDAG->allnodes_begin()) {
1489     SDNode *N = &*--Position;
1490     // Skip dead nodes and any non-machine opcodes.
1491     if (N->use_empty() || !N->isMachineOpcode())
1492       continue;
1493 
1494     if (tryOptimizeRem8Extend(N)) {
1495       MadeChange = true;
1496       continue;
1497     }
1498 
1499     // Look for a TESTrr+ANDrr pattern where both operands of the test are
1500     // the same. Rewrite to remove the AND.
1501     unsigned Opc = N->getMachineOpcode();
1502     if ((Opc == X86::TEST8rr || Opc == X86::TEST16rr ||
1503          Opc == X86::TEST32rr || Opc == X86::TEST64rr) &&
1504         N->getOperand(0) == N->getOperand(1) &&
1505         N->getOperand(0)->hasNUsesOfValue(2, N->getOperand(0).getResNo()) &&
1506         N->getOperand(0).isMachineOpcode()) {
1507       SDValue And = N->getOperand(0);
1508       unsigned N0Opc = And.getMachineOpcode();
1509       if ((N0Opc == X86::AND8rr || N0Opc == X86::AND16rr ||
1510            N0Opc == X86::AND32rr || N0Opc == X86::AND64rr) &&
1511           !And->hasAnyUseOfValue(1)) {
1512         MachineSDNode *Test = CurDAG->getMachineNode(Opc, SDLoc(N),
1513                                                      MVT::i32,
1514                                                      And.getOperand(0),
1515                                                      And.getOperand(1));
1516         ReplaceUses(N, Test);
1517         MadeChange = true;
1518         continue;
1519       }
1520       if ((N0Opc == X86::AND8rm || N0Opc == X86::AND16rm ||
1521            N0Opc == X86::AND32rm || N0Opc == X86::AND64rm) &&
1522           !And->hasAnyUseOfValue(1)) {
1523         unsigned NewOpc;
1524         switch (N0Opc) {
1525         case X86::AND8rm:  NewOpc = X86::TEST8mr; break;
1526         case X86::AND16rm: NewOpc = X86::TEST16mr; break;
1527         case X86::AND32rm: NewOpc = X86::TEST32mr; break;
1528         case X86::AND64rm: NewOpc = X86::TEST64mr; break;
1529         }
1530 
1531         // Need to swap the memory and register operand.
1532         SDValue Ops[] = { And.getOperand(1),
1533                           And.getOperand(2),
1534                           And.getOperand(3),
1535                           And.getOperand(4),
1536                           And.getOperand(5),
1537                           And.getOperand(0),
1538                           And.getOperand(6)  /* Chain */ };
1539         MachineSDNode *Test = CurDAG->getMachineNode(NewOpc, SDLoc(N),
1540                                                      MVT::i32, MVT::Other, Ops);
1541         CurDAG->setNodeMemRefs(
1542             Test, cast<MachineSDNode>(And.getNode())->memoperands());
1543         ReplaceUses(And.getValue(2), SDValue(Test, 1));
1544         ReplaceUses(SDValue(N, 0), SDValue(Test, 0));
1545         MadeChange = true;
1546         continue;
1547       }
1548     }
1549 
1550     // Look for a KAND+KORTEST and turn it into KTEST if only the zero flag is
1551     // used. We're doing this late so we can prefer to fold the AND into masked
1552     // comparisons. Doing that can be better for the live range of the mask
1553     // register.
1554     if ((Opc == X86::KORTESTBrr || Opc == X86::KORTESTWrr ||
1555          Opc == X86::KORTESTDrr || Opc == X86::KORTESTQrr) &&
1556         N->getOperand(0) == N->getOperand(1) &&
1557         N->isOnlyUserOf(N->getOperand(0).getNode()) &&
1558         N->getOperand(0).isMachineOpcode() &&
1559         onlyUsesZeroFlag(SDValue(N, 0))) {
1560       SDValue And = N->getOperand(0);
1561       unsigned N0Opc = And.getMachineOpcode();
1562       // KANDW is legal with AVX512F, but KTESTW requires AVX512DQ. The other
1563       // KAND instructions and KTEST use the same ISA feature.
1564       if (N0Opc == X86::KANDBrr ||
1565           (N0Opc == X86::KANDWrr && Subtarget->hasDQI()) ||
1566           N0Opc == X86::KANDDrr || N0Opc == X86::KANDQrr) {
1567         unsigned NewOpc;
1568         switch (Opc) {
1569         default: llvm_unreachable("Unexpected opcode!");
1570         case X86::KORTESTBrr: NewOpc = X86::KTESTBrr; break;
1571         case X86::KORTESTWrr: NewOpc = X86::KTESTWrr; break;
1572         case X86::KORTESTDrr: NewOpc = X86::KTESTDrr; break;
1573         case X86::KORTESTQrr: NewOpc = X86::KTESTQrr; break;
1574         }
1575         MachineSDNode *KTest = CurDAG->getMachineNode(NewOpc, SDLoc(N),
1576                                                       MVT::i32,
1577                                                       And.getOperand(0),
1578                                                       And.getOperand(1));
1579         ReplaceUses(N, KTest);
1580         MadeChange = true;
1581         continue;
1582       }
1583     }
1584 
1585     // Attempt to remove vectors moves that were inserted to zero upper bits.
1586     if (Opc != TargetOpcode::SUBREG_TO_REG)
1587       continue;
1588 
1589     unsigned SubRegIdx = N->getConstantOperandVal(2);
1590     if (SubRegIdx != X86::sub_xmm && SubRegIdx != X86::sub_ymm)
1591       continue;
1592 
1593     SDValue Move = N->getOperand(1);
1594     if (!Move.isMachineOpcode())
1595       continue;
1596 
1597     // Make sure its one of the move opcodes we recognize.
1598     switch (Move.getMachineOpcode()) {
1599     default:
1600       continue;
1601     case X86::VMOVAPDrr:       case X86::VMOVUPDrr:
1602     case X86::VMOVAPSrr:       case X86::VMOVUPSrr:
1603     case X86::VMOVDQArr:       case X86::VMOVDQUrr:
1604     case X86::VMOVAPDYrr:      case X86::VMOVUPDYrr:
1605     case X86::VMOVAPSYrr:      case X86::VMOVUPSYrr:
1606     case X86::VMOVDQAYrr:      case X86::VMOVDQUYrr:
1607     case X86::VMOVAPDZ128rr:   case X86::VMOVUPDZ128rr:
1608     case X86::VMOVAPSZ128rr:   case X86::VMOVUPSZ128rr:
1609     case X86::VMOVDQA32Z128rr: case X86::VMOVDQU32Z128rr:
1610     case X86::VMOVDQA64Z128rr: case X86::VMOVDQU64Z128rr:
1611     case X86::VMOVAPDZ256rr:   case X86::VMOVUPDZ256rr:
1612     case X86::VMOVAPSZ256rr:   case X86::VMOVUPSZ256rr:
1613     case X86::VMOVDQA32Z256rr: case X86::VMOVDQU32Z256rr:
1614     case X86::VMOVDQA64Z256rr: case X86::VMOVDQU64Z256rr:
1615       break;
1616     }
1617 
1618     SDValue In = Move.getOperand(0);
1619     if (!In.isMachineOpcode() ||
1620         In.getMachineOpcode() <= TargetOpcode::GENERIC_OP_END)
1621       continue;
1622 
1623     // Make sure the instruction has a VEX, XOP, or EVEX prefix. This covers
1624     // the SHA instructions which use a legacy encoding.
1625     uint64_t TSFlags = getInstrInfo()->get(In.getMachineOpcode()).TSFlags;
1626     if ((TSFlags & X86II::EncodingMask) != X86II::VEX &&
1627         (TSFlags & X86II::EncodingMask) != X86II::EVEX &&
1628         (TSFlags & X86II::EncodingMask) != X86II::XOP)
1629       continue;
1630 
1631     // Producing instruction is another vector instruction. We can drop the
1632     // move.
1633     CurDAG->UpdateNodeOperands(N, N->getOperand(0), In, N->getOperand(2));
1634     MadeChange = true;
1635   }
1636 
1637   if (MadeChange)
1638     CurDAG->RemoveDeadNodes();
1639 }
1640 
1641 
1642 /// Emit any code that needs to be executed only in the main function.
1643 void X86DAGToDAGISel::emitSpecialCodeForMain() {
1644   if (Subtarget->isTargetCygMing()) {
1645     TargetLowering::ArgListTy Args;
1646     auto &DL = CurDAG->getDataLayout();
1647 
1648     TargetLowering::CallLoweringInfo CLI(*CurDAG);
1649     CLI.setChain(CurDAG->getRoot())
1650         .setCallee(CallingConv::C, Type::getVoidTy(*CurDAG->getContext()),
1651                    CurDAG->getExternalSymbol("__main", TLI->getPointerTy(DL)),
1652                    std::move(Args));
1653     const TargetLowering &TLI = CurDAG->getTargetLoweringInfo();
1654     std::pair<SDValue, SDValue> Result = TLI.LowerCallTo(CLI);
1655     CurDAG->setRoot(Result.second);
1656   }
1657 }
1658 
1659 void X86DAGToDAGISel::emitFunctionEntryCode() {
1660   // If this is main, emit special code for main.
1661   const Function &F = MF->getFunction();
1662   if (F.hasExternalLinkage() && F.getName() == "main")
1663     emitSpecialCodeForMain();
1664 }
1665 
1666 static bool isDispSafeForFrameIndex(int64_t Val) {
1667   // On 64-bit platforms, we can run into an issue where a frame index
1668   // includes a displacement that, when added to the explicit displacement,
1669   // will overflow the displacement field. Assuming that the frame index
1670   // displacement fits into a 31-bit integer  (which is only slightly more
1671   // aggressive than the current fundamental assumption that it fits into
1672   // a 32-bit integer), a 31-bit disp should always be safe.
1673   return isInt<31>(Val);
1674 }
1675 
1676 bool X86DAGToDAGISel::foldOffsetIntoAddress(uint64_t Offset,
1677                                             X86ISelAddressMode &AM) {
1678   // We may have already matched a displacement and the caller just added the
1679   // symbolic displacement. So we still need to do the checks even if Offset
1680   // is zero.
1681 
1682   int64_t Val = AM.Disp + Offset;
1683 
1684   // Cannot combine ExternalSymbol displacements with integer offsets.
1685   if (Val != 0 && (AM.ES || AM.MCSym))
1686     return true;
1687 
1688   CodeModel::Model M = TM.getCodeModel();
1689   if (Subtarget->is64Bit()) {
1690     if (Val != 0 &&
1691         !X86::isOffsetSuitableForCodeModel(Val, M,
1692                                            AM.hasSymbolicDisplacement()))
1693       return true;
1694     // In addition to the checks required for a register base, check that
1695     // we do not try to use an unsafe Disp with a frame index.
1696     if (AM.BaseType == X86ISelAddressMode::FrameIndexBase &&
1697         !isDispSafeForFrameIndex(Val))
1698       return true;
1699   }
1700   AM.Disp = Val;
1701   return false;
1702 
1703 }
1704 
1705 bool X86DAGToDAGISel::matchLoadInAddress(LoadSDNode *N, X86ISelAddressMode &AM,
1706                                          bool AllowSegmentRegForX32) {
1707   SDValue Address = N->getOperand(1);
1708 
1709   // load gs:0 -> GS segment register.
1710   // load fs:0 -> FS segment register.
1711   //
1712   // This optimization is generally valid because the GNU TLS model defines that
1713   // gs:0 (or fs:0 on X86-64) contains its own address. However, for X86-64 mode
1714   // with 32-bit registers, as we get in ILP32 mode, those registers are first
1715   // zero-extended to 64 bits and then added it to the base address, which gives
1716   // unwanted results when the register holds a negative value.
1717   // For more information see http://people.redhat.com/drepper/tls.pdf
1718   if (isNullConstant(Address) && AM.Segment.getNode() == nullptr &&
1719       !IndirectTlsSegRefs &&
1720       (Subtarget->isTargetGlibc() || Subtarget->isTargetAndroid() ||
1721        Subtarget->isTargetFuchsia())) {
1722     if (Subtarget->isTarget64BitILP32() && !AllowSegmentRegForX32)
1723       return true;
1724     switch (N->getPointerInfo().getAddrSpace()) {
1725     case X86AS::GS:
1726       AM.Segment = CurDAG->getRegister(X86::GS, MVT::i16);
1727       return false;
1728     case X86AS::FS:
1729       AM.Segment = CurDAG->getRegister(X86::FS, MVT::i16);
1730       return false;
1731       // Address space X86AS::SS is not handled here, because it is not used to
1732       // address TLS areas.
1733     }
1734   }
1735 
1736   return true;
1737 }
1738 
1739 /// Try to match X86ISD::Wrapper and X86ISD::WrapperRIP nodes into an addressing
1740 /// mode. These wrap things that will resolve down into a symbol reference.
1741 /// If no match is possible, this returns true, otherwise it returns false.
1742 bool X86DAGToDAGISel::matchWrapper(SDValue N, X86ISelAddressMode &AM) {
1743   // If the addressing mode already has a symbol as the displacement, we can
1744   // never match another symbol.
1745   if (AM.hasSymbolicDisplacement())
1746     return true;
1747 
1748   bool IsRIPRelTLS = false;
1749   bool IsRIPRel = N.getOpcode() == X86ISD::WrapperRIP;
1750   if (IsRIPRel) {
1751     SDValue Val = N.getOperand(0);
1752     if (Val.getOpcode() == ISD::TargetGlobalTLSAddress)
1753       IsRIPRelTLS = true;
1754   }
1755 
1756   // We can't use an addressing mode in the 64-bit large code model.
1757   // Global TLS addressing is an exception. In the medium code model,
1758   // we use can use a mode when RIP wrappers are present.
1759   // That signifies access to globals that are known to be "near",
1760   // such as the GOT itself.
1761   CodeModel::Model M = TM.getCodeModel();
1762   if (Subtarget->is64Bit() &&
1763       ((M == CodeModel::Large && !IsRIPRelTLS) ||
1764        (M == CodeModel::Medium && !IsRIPRel)))
1765     return true;
1766 
1767   // Base and index reg must be 0 in order to use %rip as base.
1768   if (IsRIPRel && AM.hasBaseOrIndexReg())
1769     return true;
1770 
1771   // Make a local copy in case we can't do this fold.
1772   X86ISelAddressMode Backup = AM;
1773 
1774   int64_t Offset = 0;
1775   SDValue N0 = N.getOperand(0);
1776   if (auto *G = dyn_cast<GlobalAddressSDNode>(N0)) {
1777     AM.GV = G->getGlobal();
1778     AM.SymbolFlags = G->getTargetFlags();
1779     Offset = G->getOffset();
1780   } else if (auto *CP = dyn_cast<ConstantPoolSDNode>(N0)) {
1781     AM.CP = CP->getConstVal();
1782     AM.Alignment = CP->getAlign();
1783     AM.SymbolFlags = CP->getTargetFlags();
1784     Offset = CP->getOffset();
1785   } else if (auto *S = dyn_cast<ExternalSymbolSDNode>(N0)) {
1786     AM.ES = S->getSymbol();
1787     AM.SymbolFlags = S->getTargetFlags();
1788   } else if (auto *S = dyn_cast<MCSymbolSDNode>(N0)) {
1789     AM.MCSym = S->getMCSymbol();
1790   } else if (auto *J = dyn_cast<JumpTableSDNode>(N0)) {
1791     AM.JT = J->getIndex();
1792     AM.SymbolFlags = J->getTargetFlags();
1793   } else if (auto *BA = dyn_cast<BlockAddressSDNode>(N0)) {
1794     AM.BlockAddr = BA->getBlockAddress();
1795     AM.SymbolFlags = BA->getTargetFlags();
1796     Offset = BA->getOffset();
1797   } else
1798     llvm_unreachable("Unhandled symbol reference node.");
1799 
1800   if (foldOffsetIntoAddress(Offset, AM)) {
1801     AM = Backup;
1802     return true;
1803   }
1804 
1805   if (IsRIPRel)
1806     AM.setBaseReg(CurDAG->getRegister(X86::RIP, MVT::i64));
1807 
1808   // Commit the changes now that we know this fold is safe.
1809   return false;
1810 }
1811 
1812 /// Add the specified node to the specified addressing mode, returning true if
1813 /// it cannot be done. This just pattern matches for the addressing mode.
1814 bool X86DAGToDAGISel::matchAddress(SDValue N, X86ISelAddressMode &AM) {
1815   if (matchAddressRecursively(N, AM, 0))
1816     return true;
1817 
1818   // Post-processing: Make a second attempt to fold a load, if we now know
1819   // that there will not be any other register. This is only performed for
1820   // 64-bit ILP32 mode since 32-bit mode and 64-bit LP64 mode will have folded
1821   // any foldable load the first time.
1822   if (Subtarget->isTarget64BitILP32() &&
1823       AM.BaseType == X86ISelAddressMode::RegBase &&
1824       AM.Base_Reg.getNode() != nullptr && AM.IndexReg.getNode() == nullptr) {
1825     SDValue Save_Base_Reg = AM.Base_Reg;
1826     if (auto *LoadN = dyn_cast<LoadSDNode>(Save_Base_Reg)) {
1827       AM.Base_Reg = SDValue();
1828       if (matchLoadInAddress(LoadN, AM, /*AllowSegmentRegForX32=*/true))
1829         AM.Base_Reg = Save_Base_Reg;
1830     }
1831   }
1832 
1833   // Post-processing: Convert lea(,%reg,2) to lea(%reg,%reg), which has
1834   // a smaller encoding and avoids a scaled-index.
1835   if (AM.Scale == 2 &&
1836       AM.BaseType == X86ISelAddressMode::RegBase &&
1837       AM.Base_Reg.getNode() == nullptr) {
1838     AM.Base_Reg = AM.IndexReg;
1839     AM.Scale = 1;
1840   }
1841 
1842   // Post-processing: Convert foo to foo(%rip), even in non-PIC mode,
1843   // because it has a smaller encoding.
1844   // TODO: Which other code models can use this?
1845   switch (TM.getCodeModel()) {
1846     default: break;
1847     case CodeModel::Small:
1848     case CodeModel::Kernel:
1849       if (Subtarget->is64Bit() &&
1850           AM.Scale == 1 &&
1851           AM.BaseType == X86ISelAddressMode::RegBase &&
1852           AM.Base_Reg.getNode() == nullptr &&
1853           AM.IndexReg.getNode() == nullptr &&
1854           AM.SymbolFlags == X86II::MO_NO_FLAG &&
1855           AM.hasSymbolicDisplacement())
1856         AM.Base_Reg = CurDAG->getRegister(X86::RIP, MVT::i64);
1857       break;
1858   }
1859 
1860   return false;
1861 }
1862 
1863 bool X86DAGToDAGISel::matchAdd(SDValue &N, X86ISelAddressMode &AM,
1864                                unsigned Depth) {
1865   // Add an artificial use to this node so that we can keep track of
1866   // it if it gets CSE'd with a different node.
1867   HandleSDNode Handle(N);
1868 
1869   X86ISelAddressMode Backup = AM;
1870   if (!matchAddressRecursively(N.getOperand(0), AM, Depth+1) &&
1871       !matchAddressRecursively(Handle.getValue().getOperand(1), AM, Depth+1))
1872     return false;
1873   AM = Backup;
1874 
1875   // Try again after commutating the operands.
1876   if (!matchAddressRecursively(Handle.getValue().getOperand(1), AM,
1877                                Depth + 1) &&
1878       !matchAddressRecursively(Handle.getValue().getOperand(0), AM, Depth + 1))
1879     return false;
1880   AM = Backup;
1881 
1882   // If we couldn't fold both operands into the address at the same time,
1883   // see if we can just put each operand into a register and fold at least
1884   // the add.
1885   if (AM.BaseType == X86ISelAddressMode::RegBase &&
1886       !AM.Base_Reg.getNode() &&
1887       !AM.IndexReg.getNode()) {
1888     N = Handle.getValue();
1889     AM.Base_Reg = N.getOperand(0);
1890     AM.IndexReg = N.getOperand(1);
1891     AM.Scale = 1;
1892     return false;
1893   }
1894   N = Handle.getValue();
1895   return true;
1896 }
1897 
1898 // Insert a node into the DAG at least before the Pos node's position. This
1899 // will reposition the node as needed, and will assign it a node ID that is <=
1900 // the Pos node's ID. Note that this does *not* preserve the uniqueness of node
1901 // IDs! The selection DAG must no longer depend on their uniqueness when this
1902 // is used.
1903 static void insertDAGNode(SelectionDAG &DAG, SDValue Pos, SDValue N) {
1904   if (N->getNodeId() == -1 ||
1905       (SelectionDAGISel::getUninvalidatedNodeId(N.getNode()) >
1906        SelectionDAGISel::getUninvalidatedNodeId(Pos.getNode()))) {
1907     DAG.RepositionNode(Pos->getIterator(), N.getNode());
1908     // Mark Node as invalid for pruning as after this it may be a successor to a
1909     // selected node but otherwise be in the same position of Pos.
1910     // Conservatively mark it with the same -abs(Id) to assure node id
1911     // invariant is preserved.
1912     N->setNodeId(Pos->getNodeId());
1913     SelectionDAGISel::InvalidateNodeId(N.getNode());
1914   }
1915 }
1916 
1917 // Transform "(X >> (8-C1)) & (0xff << C1)" to "((X >> 8) & 0xff) << C1" if
1918 // safe. This allows us to convert the shift and and into an h-register
1919 // extract and a scaled index. Returns false if the simplification is
1920 // performed.
1921 static bool foldMaskAndShiftToExtract(SelectionDAG &DAG, SDValue N,
1922                                       uint64_t Mask,
1923                                       SDValue Shift, SDValue X,
1924                                       X86ISelAddressMode &AM) {
1925   if (Shift.getOpcode() != ISD::SRL ||
1926       !isa<ConstantSDNode>(Shift.getOperand(1)) ||
1927       !Shift.hasOneUse())
1928     return true;
1929 
1930   int ScaleLog = 8 - Shift.getConstantOperandVal(1);
1931   if (ScaleLog <= 0 || ScaleLog >= 4 ||
1932       Mask != (0xffu << ScaleLog))
1933     return true;
1934 
1935   MVT XVT = X.getSimpleValueType();
1936   MVT VT = N.getSimpleValueType();
1937   SDLoc DL(N);
1938   SDValue Eight = DAG.getConstant(8, DL, MVT::i8);
1939   SDValue NewMask = DAG.getConstant(0xff, DL, XVT);
1940   SDValue Srl = DAG.getNode(ISD::SRL, DL, XVT, X, Eight);
1941   SDValue And = DAG.getNode(ISD::AND, DL, XVT, Srl, NewMask);
1942   SDValue ShlCount = DAG.getConstant(ScaleLog, DL, MVT::i8);
1943   SDValue Ext = DAG.getZExtOrTrunc(And, DL, VT);
1944   SDValue Shl = DAG.getNode(ISD::SHL, DL, VT, Ext, ShlCount);
1945 
1946   // Insert the new nodes into the topological ordering. We must do this in
1947   // a valid topological ordering as nothing is going to go back and re-sort
1948   // these nodes. We continually insert before 'N' in sequence as this is
1949   // essentially a pre-flattened and pre-sorted sequence of nodes. There is no
1950   // hierarchy left to express.
1951   insertDAGNode(DAG, N, Eight);
1952   insertDAGNode(DAG, N, Srl);
1953   insertDAGNode(DAG, N, NewMask);
1954   insertDAGNode(DAG, N, And);
1955   insertDAGNode(DAG, N, ShlCount);
1956   if (Ext != And)
1957     insertDAGNode(DAG, N, Ext);
1958   insertDAGNode(DAG, N, Shl);
1959   DAG.ReplaceAllUsesWith(N, Shl);
1960   DAG.RemoveDeadNode(N.getNode());
1961   AM.IndexReg = Ext;
1962   AM.Scale = (1 << ScaleLog);
1963   return false;
1964 }
1965 
1966 // Transforms "(X << C1) & C2" to "(X & (C2>>C1)) << C1" if safe and if this
1967 // allows us to fold the shift into this addressing mode. Returns false if the
1968 // transform succeeded.
1969 static bool foldMaskedShiftToScaledMask(SelectionDAG &DAG, SDValue N,
1970                                         X86ISelAddressMode &AM) {
1971   SDValue Shift = N.getOperand(0);
1972 
1973   // Use a signed mask so that shifting right will insert sign bits. These
1974   // bits will be removed when we shift the result left so it doesn't matter
1975   // what we use. This might allow a smaller immediate encoding.
1976   int64_t Mask = cast<ConstantSDNode>(N->getOperand(1))->getSExtValue();
1977 
1978   // If we have an any_extend feeding the AND, look through it to see if there
1979   // is a shift behind it. But only if the AND doesn't use the extended bits.
1980   // FIXME: Generalize this to other ANY_EXTEND than i32 to i64?
1981   bool FoundAnyExtend = false;
1982   if (Shift.getOpcode() == ISD::ANY_EXTEND && Shift.hasOneUse() &&
1983       Shift.getOperand(0).getSimpleValueType() == MVT::i32 &&
1984       isUInt<32>(Mask)) {
1985     FoundAnyExtend = true;
1986     Shift = Shift.getOperand(0);
1987   }
1988 
1989   if (Shift.getOpcode() != ISD::SHL ||
1990       !isa<ConstantSDNode>(Shift.getOperand(1)))
1991     return true;
1992 
1993   SDValue X = Shift.getOperand(0);
1994 
1995   // Not likely to be profitable if either the AND or SHIFT node has more
1996   // than one use (unless all uses are for address computation). Besides,
1997   // isel mechanism requires their node ids to be reused.
1998   if (!N.hasOneUse() || !Shift.hasOneUse())
1999     return true;
2000 
2001   // Verify that the shift amount is something we can fold.
2002   unsigned ShiftAmt = Shift.getConstantOperandVal(1);
2003   if (ShiftAmt != 1 && ShiftAmt != 2 && ShiftAmt != 3)
2004     return true;
2005 
2006   MVT VT = N.getSimpleValueType();
2007   SDLoc DL(N);
2008   if (FoundAnyExtend) {
2009     SDValue NewX = DAG.getNode(ISD::ANY_EXTEND, DL, VT, X);
2010     insertDAGNode(DAG, N, NewX);
2011     X = NewX;
2012   }
2013 
2014   SDValue NewMask = DAG.getConstant(Mask >> ShiftAmt, DL, VT);
2015   SDValue NewAnd = DAG.getNode(ISD::AND, DL, VT, X, NewMask);
2016   SDValue NewShift = DAG.getNode(ISD::SHL, DL, VT, NewAnd, Shift.getOperand(1));
2017 
2018   // Insert the new nodes into the topological ordering. We must do this in
2019   // a valid topological ordering as nothing is going to go back and re-sort
2020   // these nodes. We continually insert before 'N' in sequence as this is
2021   // essentially a pre-flattened and pre-sorted sequence of nodes. There is no
2022   // hierarchy left to express.
2023   insertDAGNode(DAG, N, NewMask);
2024   insertDAGNode(DAG, N, NewAnd);
2025   insertDAGNode(DAG, N, NewShift);
2026   DAG.ReplaceAllUsesWith(N, NewShift);
2027   DAG.RemoveDeadNode(N.getNode());
2028 
2029   AM.Scale = 1 << ShiftAmt;
2030   AM.IndexReg = NewAnd;
2031   return false;
2032 }
2033 
2034 // Implement some heroics to detect shifts of masked values where the mask can
2035 // be replaced by extending the shift and undoing that in the addressing mode
2036 // scale. Patterns such as (shl (srl x, c1), c2) are canonicalized into (and
2037 // (srl x, SHIFT), MASK) by DAGCombines that don't know the shl can be done in
2038 // the addressing mode. This results in code such as:
2039 //
2040 //   int f(short *y, int *lookup_table) {
2041 //     ...
2042 //     return *y + lookup_table[*y >> 11];
2043 //   }
2044 //
2045 // Turning into:
2046 //   movzwl (%rdi), %eax
2047 //   movl %eax, %ecx
2048 //   shrl $11, %ecx
2049 //   addl (%rsi,%rcx,4), %eax
2050 //
2051 // Instead of:
2052 //   movzwl (%rdi), %eax
2053 //   movl %eax, %ecx
2054 //   shrl $9, %ecx
2055 //   andl $124, %rcx
2056 //   addl (%rsi,%rcx), %eax
2057 //
2058 // Note that this function assumes the mask is provided as a mask *after* the
2059 // value is shifted. The input chain may or may not match that, but computing
2060 // such a mask is trivial.
2061 static bool foldMaskAndShiftToScale(SelectionDAG &DAG, SDValue N,
2062                                     uint64_t Mask,
2063                                     SDValue Shift, SDValue X,
2064                                     X86ISelAddressMode &AM) {
2065   if (Shift.getOpcode() != ISD::SRL || !Shift.hasOneUse() ||
2066       !isa<ConstantSDNode>(Shift.getOperand(1)))
2067     return true;
2068 
2069   unsigned ShiftAmt = Shift.getConstantOperandVal(1);
2070   unsigned MaskLZ = llvm::countl_zero(Mask);
2071   unsigned MaskTZ = llvm::countr_zero(Mask);
2072 
2073   // The amount of shift we're trying to fit into the addressing mode is taken
2074   // from the trailing zeros of the mask.
2075   unsigned AMShiftAmt = MaskTZ;
2076 
2077   // There is nothing we can do here unless the mask is removing some bits.
2078   // Also, the addressing mode can only represent shifts of 1, 2, or 3 bits.
2079   if (AMShiftAmt == 0 || AMShiftAmt > 3) return true;
2080 
2081   // We also need to ensure that mask is a continuous run of bits.
2082   if (llvm::countr_one(Mask >> MaskTZ) + MaskTZ + MaskLZ != 64)
2083     return true;
2084 
2085   // Scale the leading zero count down based on the actual size of the value.
2086   // Also scale it down based on the size of the shift.
2087   unsigned ScaleDown = (64 - X.getSimpleValueType().getSizeInBits()) + ShiftAmt;
2088   if (MaskLZ < ScaleDown)
2089     return true;
2090   MaskLZ -= ScaleDown;
2091 
2092   // The final check is to ensure that any masked out high bits of X are
2093   // already known to be zero. Otherwise, the mask has a semantic impact
2094   // other than masking out a couple of low bits. Unfortunately, because of
2095   // the mask, zero extensions will be removed from operands in some cases.
2096   // This code works extra hard to look through extensions because we can
2097   // replace them with zero extensions cheaply if necessary.
2098   bool ReplacingAnyExtend = false;
2099   if (X.getOpcode() == ISD::ANY_EXTEND) {
2100     unsigned ExtendBits = X.getSimpleValueType().getSizeInBits() -
2101                           X.getOperand(0).getSimpleValueType().getSizeInBits();
2102     // Assume that we'll replace the any-extend with a zero-extend, and
2103     // narrow the search to the extended value.
2104     X = X.getOperand(0);
2105     MaskLZ = ExtendBits > MaskLZ ? 0 : MaskLZ - ExtendBits;
2106     ReplacingAnyExtend = true;
2107   }
2108   APInt MaskedHighBits =
2109     APInt::getHighBitsSet(X.getSimpleValueType().getSizeInBits(), MaskLZ);
2110   KnownBits Known = DAG.computeKnownBits(X);
2111   if (MaskedHighBits != Known.Zero) return true;
2112 
2113   // We've identified a pattern that can be transformed into a single shift
2114   // and an addressing mode. Make it so.
2115   MVT VT = N.getSimpleValueType();
2116   if (ReplacingAnyExtend) {
2117     assert(X.getValueType() != VT);
2118     // We looked through an ANY_EXTEND node, insert a ZERO_EXTEND.
2119     SDValue NewX = DAG.getNode(ISD::ZERO_EXTEND, SDLoc(X), VT, X);
2120     insertDAGNode(DAG, N, NewX);
2121     X = NewX;
2122   }
2123   SDLoc DL(N);
2124   SDValue NewSRLAmt = DAG.getConstant(ShiftAmt + AMShiftAmt, DL, MVT::i8);
2125   SDValue NewSRL = DAG.getNode(ISD::SRL, DL, VT, X, NewSRLAmt);
2126   SDValue NewSHLAmt = DAG.getConstant(AMShiftAmt, DL, MVT::i8);
2127   SDValue NewSHL = DAG.getNode(ISD::SHL, DL, VT, NewSRL, NewSHLAmt);
2128 
2129   // Insert the new nodes into the topological ordering. We must do this in
2130   // a valid topological ordering as nothing is going to go back and re-sort
2131   // these nodes. We continually insert before 'N' in sequence as this is
2132   // essentially a pre-flattened and pre-sorted sequence of nodes. There is no
2133   // hierarchy left to express.
2134   insertDAGNode(DAG, N, NewSRLAmt);
2135   insertDAGNode(DAG, N, NewSRL);
2136   insertDAGNode(DAG, N, NewSHLAmt);
2137   insertDAGNode(DAG, N, NewSHL);
2138   DAG.ReplaceAllUsesWith(N, NewSHL);
2139   DAG.RemoveDeadNode(N.getNode());
2140 
2141   AM.Scale = 1 << AMShiftAmt;
2142   AM.IndexReg = NewSRL;
2143   return false;
2144 }
2145 
2146 // Transform "(X >> SHIFT) & (MASK << C1)" to
2147 // "((X >> (SHIFT + C1)) & (MASK)) << C1". Everything before the SHL will be
2148 // matched to a BEXTR later. Returns false if the simplification is performed.
2149 static bool foldMaskedShiftToBEXTR(SelectionDAG &DAG, SDValue N,
2150                                    uint64_t Mask,
2151                                    SDValue Shift, SDValue X,
2152                                    X86ISelAddressMode &AM,
2153                                    const X86Subtarget &Subtarget) {
2154   if (Shift.getOpcode() != ISD::SRL ||
2155       !isa<ConstantSDNode>(Shift.getOperand(1)) ||
2156       !Shift.hasOneUse() || !N.hasOneUse())
2157     return true;
2158 
2159   // Only do this if BEXTR will be matched by matchBEXTRFromAndImm.
2160   if (!Subtarget.hasTBM() &&
2161       !(Subtarget.hasBMI() && Subtarget.hasFastBEXTR()))
2162     return true;
2163 
2164   // We need to ensure that mask is a continuous run of bits.
2165   if (!isShiftedMask_64(Mask)) return true;
2166 
2167   unsigned ShiftAmt = Shift.getConstantOperandVal(1);
2168 
2169   // The amount of shift we're trying to fit into the addressing mode is taken
2170   // from the trailing zeros of the mask.
2171   unsigned AMShiftAmt = llvm::countr_zero(Mask);
2172 
2173   // There is nothing we can do here unless the mask is removing some bits.
2174   // Also, the addressing mode can only represent shifts of 1, 2, or 3 bits.
2175   if (AMShiftAmt == 0 || AMShiftAmt > 3) return true;
2176 
2177   MVT VT = N.getSimpleValueType();
2178   SDLoc DL(N);
2179   SDValue NewSRLAmt = DAG.getConstant(ShiftAmt + AMShiftAmt, DL, MVT::i8);
2180   SDValue NewSRL = DAG.getNode(ISD::SRL, DL, VT, X, NewSRLAmt);
2181   SDValue NewMask = DAG.getConstant(Mask >> AMShiftAmt, DL, VT);
2182   SDValue NewAnd = DAG.getNode(ISD::AND, DL, VT, NewSRL, NewMask);
2183   SDValue NewSHLAmt = DAG.getConstant(AMShiftAmt, DL, MVT::i8);
2184   SDValue NewSHL = DAG.getNode(ISD::SHL, DL, VT, NewAnd, NewSHLAmt);
2185 
2186   // Insert the new nodes into the topological ordering. We must do this in
2187   // a valid topological ordering as nothing is going to go back and re-sort
2188   // these nodes. We continually insert before 'N' in sequence as this is
2189   // essentially a pre-flattened and pre-sorted sequence of nodes. There is no
2190   // hierarchy left to express.
2191   insertDAGNode(DAG, N, NewSRLAmt);
2192   insertDAGNode(DAG, N, NewSRL);
2193   insertDAGNode(DAG, N, NewMask);
2194   insertDAGNode(DAG, N, NewAnd);
2195   insertDAGNode(DAG, N, NewSHLAmt);
2196   insertDAGNode(DAG, N, NewSHL);
2197   DAG.ReplaceAllUsesWith(N, NewSHL);
2198   DAG.RemoveDeadNode(N.getNode());
2199 
2200   AM.Scale = 1 << AMShiftAmt;
2201   AM.IndexReg = NewAnd;
2202   return false;
2203 }
2204 
2205 bool X86DAGToDAGISel::matchAddressRecursively(SDValue N, X86ISelAddressMode &AM,
2206                                               unsigned Depth) {
2207   SDLoc dl(N);
2208   LLVM_DEBUG({
2209     dbgs() << "MatchAddress: ";
2210     AM.dump(CurDAG);
2211   });
2212   // Limit recursion.
2213   if (Depth > 5)
2214     return matchAddressBase(N, AM);
2215 
2216   // If this is already a %rip relative address, we can only merge immediates
2217   // into it.  Instead of handling this in every case, we handle it here.
2218   // RIP relative addressing: %rip + 32-bit displacement!
2219   if (AM.isRIPRelative()) {
2220     // FIXME: JumpTable and ExternalSymbol address currently don't like
2221     // displacements.  It isn't very important, but this should be fixed for
2222     // consistency.
2223     if (!(AM.ES || AM.MCSym) && AM.JT != -1)
2224       return true;
2225 
2226     if (auto *Cst = dyn_cast<ConstantSDNode>(N))
2227       if (!foldOffsetIntoAddress(Cst->getSExtValue(), AM))
2228         return false;
2229     return true;
2230   }
2231 
2232   switch (N.getOpcode()) {
2233   default: break;
2234   case ISD::LOCAL_RECOVER: {
2235     if (!AM.hasSymbolicDisplacement() && AM.Disp == 0)
2236       if (const auto *ESNode = dyn_cast<MCSymbolSDNode>(N.getOperand(0))) {
2237         // Use the symbol and don't prefix it.
2238         AM.MCSym = ESNode->getMCSymbol();
2239         return false;
2240       }
2241     break;
2242   }
2243   case ISD::Constant: {
2244     uint64_t Val = cast<ConstantSDNode>(N)->getSExtValue();
2245     if (!foldOffsetIntoAddress(Val, AM))
2246       return false;
2247     break;
2248   }
2249 
2250   case X86ISD::Wrapper:
2251   case X86ISD::WrapperRIP:
2252     if (!matchWrapper(N, AM))
2253       return false;
2254     break;
2255 
2256   case ISD::LOAD:
2257     if (!matchLoadInAddress(cast<LoadSDNode>(N), AM))
2258       return false;
2259     break;
2260 
2261   case ISD::FrameIndex:
2262     if (AM.BaseType == X86ISelAddressMode::RegBase &&
2263         AM.Base_Reg.getNode() == nullptr &&
2264         (!Subtarget->is64Bit() || isDispSafeForFrameIndex(AM.Disp))) {
2265       AM.BaseType = X86ISelAddressMode::FrameIndexBase;
2266       AM.Base_FrameIndex = cast<FrameIndexSDNode>(N)->getIndex();
2267       return false;
2268     }
2269     break;
2270 
2271   case ISD::SHL:
2272     if (AM.IndexReg.getNode() != nullptr || AM.Scale != 1)
2273       break;
2274 
2275     if (auto *CN = dyn_cast<ConstantSDNode>(N.getOperand(1))) {
2276       unsigned Val = CN->getZExtValue();
2277       // Note that we handle x<<1 as (,x,2) rather than (x,x) here so
2278       // that the base operand remains free for further matching. If
2279       // the base doesn't end up getting used, a post-processing step
2280       // in MatchAddress turns (,x,2) into (x,x), which is cheaper.
2281       if (Val == 1 || Val == 2 || Val == 3) {
2282         AM.Scale = 1 << Val;
2283         SDValue ShVal = N.getOperand(0);
2284 
2285         // Okay, we know that we have a scale by now.  However, if the scaled
2286         // value is an add of something and a constant, we can fold the
2287         // constant into the disp field here.
2288         if (CurDAG->isBaseWithConstantOffset(ShVal)) {
2289           AM.IndexReg = ShVal.getOperand(0);
2290           auto *AddVal = cast<ConstantSDNode>(ShVal.getOperand(1));
2291           uint64_t Disp = (uint64_t)AddVal->getSExtValue() << Val;
2292           if (!foldOffsetIntoAddress(Disp, AM))
2293             return false;
2294         }
2295 
2296         AM.IndexReg = ShVal;
2297         return false;
2298       }
2299     }
2300     break;
2301 
2302   case ISD::SRL: {
2303     // Scale must not be used already.
2304     if (AM.IndexReg.getNode() != nullptr || AM.Scale != 1) break;
2305 
2306     // We only handle up to 64-bit values here as those are what matter for
2307     // addressing mode optimizations.
2308     assert(N.getSimpleValueType().getSizeInBits() <= 64 &&
2309            "Unexpected value size!");
2310 
2311     SDValue And = N.getOperand(0);
2312     if (And.getOpcode() != ISD::AND) break;
2313     SDValue X = And.getOperand(0);
2314 
2315     // The mask used for the transform is expected to be post-shift, but we
2316     // found the shift first so just apply the shift to the mask before passing
2317     // it down.
2318     if (!isa<ConstantSDNode>(N.getOperand(1)) ||
2319         !isa<ConstantSDNode>(And.getOperand(1)))
2320       break;
2321     uint64_t Mask = And.getConstantOperandVal(1) >> N.getConstantOperandVal(1);
2322 
2323     // Try to fold the mask and shift into the scale, and return false if we
2324     // succeed.
2325     if (!foldMaskAndShiftToScale(*CurDAG, N, Mask, N, X, AM))
2326       return false;
2327     break;
2328   }
2329 
2330   case ISD::SMUL_LOHI:
2331   case ISD::UMUL_LOHI:
2332     // A mul_lohi where we need the low part can be folded as a plain multiply.
2333     if (N.getResNo() != 0) break;
2334     [[fallthrough]];
2335   case ISD::MUL:
2336   case X86ISD::MUL_IMM:
2337     // X*[3,5,9] -> X+X*[2,4,8]
2338     if (AM.BaseType == X86ISelAddressMode::RegBase &&
2339         AM.Base_Reg.getNode() == nullptr &&
2340         AM.IndexReg.getNode() == nullptr) {
2341       if (auto *CN = dyn_cast<ConstantSDNode>(N.getOperand(1)))
2342         if (CN->getZExtValue() == 3 || CN->getZExtValue() == 5 ||
2343             CN->getZExtValue() == 9) {
2344           AM.Scale = unsigned(CN->getZExtValue())-1;
2345 
2346           SDValue MulVal = N.getOperand(0);
2347           SDValue Reg;
2348 
2349           // Okay, we know that we have a scale by now.  However, if the scaled
2350           // value is an add of something and a constant, we can fold the
2351           // constant into the disp field here.
2352           if (MulVal.getNode()->getOpcode() == ISD::ADD && MulVal.hasOneUse() &&
2353               isa<ConstantSDNode>(MulVal.getOperand(1))) {
2354             Reg = MulVal.getOperand(0);
2355             auto *AddVal = cast<ConstantSDNode>(MulVal.getOperand(1));
2356             uint64_t Disp = AddVal->getSExtValue() * CN->getZExtValue();
2357             if (foldOffsetIntoAddress(Disp, AM))
2358               Reg = N.getOperand(0);
2359           } else {
2360             Reg = N.getOperand(0);
2361           }
2362 
2363           AM.IndexReg = AM.Base_Reg = Reg;
2364           return false;
2365         }
2366     }
2367     break;
2368 
2369   case ISD::SUB: {
2370     // Given A-B, if A can be completely folded into the address and
2371     // the index field with the index field unused, use -B as the index.
2372     // This is a win if a has multiple parts that can be folded into
2373     // the address. Also, this saves a mov if the base register has
2374     // other uses, since it avoids a two-address sub instruction, however
2375     // it costs an additional mov if the index register has other uses.
2376 
2377     // Add an artificial use to this node so that we can keep track of
2378     // it if it gets CSE'd with a different node.
2379     HandleSDNode Handle(N);
2380 
2381     // Test if the LHS of the sub can be folded.
2382     X86ISelAddressMode Backup = AM;
2383     if (matchAddressRecursively(N.getOperand(0), AM, Depth+1)) {
2384       N = Handle.getValue();
2385       AM = Backup;
2386       break;
2387     }
2388     N = Handle.getValue();
2389     // Test if the index field is free for use.
2390     if (AM.IndexReg.getNode() || AM.isRIPRelative()) {
2391       AM = Backup;
2392       break;
2393     }
2394 
2395     int Cost = 0;
2396     SDValue RHS = N.getOperand(1);
2397     // If the RHS involves a register with multiple uses, this
2398     // transformation incurs an extra mov, due to the neg instruction
2399     // clobbering its operand.
2400     if (!RHS.getNode()->hasOneUse() ||
2401         RHS.getNode()->getOpcode() == ISD::CopyFromReg ||
2402         RHS.getNode()->getOpcode() == ISD::TRUNCATE ||
2403         RHS.getNode()->getOpcode() == ISD::ANY_EXTEND ||
2404         (RHS.getNode()->getOpcode() == ISD::ZERO_EXTEND &&
2405          RHS.getOperand(0).getValueType() == MVT::i32))
2406       ++Cost;
2407     // If the base is a register with multiple uses, this
2408     // transformation may save a mov.
2409     if ((AM.BaseType == X86ISelAddressMode::RegBase && AM.Base_Reg.getNode() &&
2410          !AM.Base_Reg.getNode()->hasOneUse()) ||
2411         AM.BaseType == X86ISelAddressMode::FrameIndexBase)
2412       --Cost;
2413     // If the folded LHS was interesting, this transformation saves
2414     // address arithmetic.
2415     if ((AM.hasSymbolicDisplacement() && !Backup.hasSymbolicDisplacement()) +
2416         ((AM.Disp != 0) && (Backup.Disp == 0)) +
2417         (AM.Segment.getNode() && !Backup.Segment.getNode()) >= 2)
2418       --Cost;
2419     // If it doesn't look like it may be an overall win, don't do it.
2420     if (Cost >= 0) {
2421       AM = Backup;
2422       break;
2423     }
2424 
2425     // Ok, the transformation is legal and appears profitable. Go for it.
2426     // Negation will be emitted later to avoid creating dangling nodes if this
2427     // was an unprofitable LEA.
2428     AM.IndexReg = RHS;
2429     AM.NegateIndex = true;
2430     AM.Scale = 1;
2431     return false;
2432   }
2433 
2434   case ISD::ADD:
2435     if (!matchAdd(N, AM, Depth))
2436       return false;
2437     break;
2438 
2439   case ISD::OR:
2440     // We want to look through a transform in InstCombine and DAGCombiner that
2441     // turns 'add' into 'or', so we can treat this 'or' exactly like an 'add'.
2442     // Example: (or (and x, 1), (shl y, 3)) --> (add (and x, 1), (shl y, 3))
2443     // An 'lea' can then be used to match the shift (multiply) and add:
2444     // and $1, %esi
2445     // lea (%rsi, %rdi, 8), %rax
2446     if (CurDAG->haveNoCommonBitsSet(N.getOperand(0), N.getOperand(1)) &&
2447         !matchAdd(N, AM, Depth))
2448       return false;
2449     break;
2450 
2451   case ISD::XOR:
2452     // We want to look through a transform in InstCombine that
2453     // turns 'add' with min_signed_val into 'xor', so we can treat this 'xor'
2454     // exactly like an 'add'.
2455     if (isMinSignedConstant(N.getOperand(1)) && !matchAdd(N, AM, Depth))
2456       return false;
2457     break;
2458 
2459   case ISD::AND: {
2460     // Perform some heroic transforms on an and of a constant-count shift
2461     // with a constant to enable use of the scaled offset field.
2462 
2463     // Scale must not be used already.
2464     if (AM.IndexReg.getNode() != nullptr || AM.Scale != 1) break;
2465 
2466     // We only handle up to 64-bit values here as those are what matter for
2467     // addressing mode optimizations.
2468     assert(N.getSimpleValueType().getSizeInBits() <= 64 &&
2469            "Unexpected value size!");
2470 
2471     if (!isa<ConstantSDNode>(N.getOperand(1)))
2472       break;
2473 
2474     if (N.getOperand(0).getOpcode() == ISD::SRL) {
2475       SDValue Shift = N.getOperand(0);
2476       SDValue X = Shift.getOperand(0);
2477 
2478       uint64_t Mask = N.getConstantOperandVal(1);
2479 
2480       // Try to fold the mask and shift into an extract and scale.
2481       if (!foldMaskAndShiftToExtract(*CurDAG, N, Mask, Shift, X, AM))
2482         return false;
2483 
2484       // Try to fold the mask and shift directly into the scale.
2485       if (!foldMaskAndShiftToScale(*CurDAG, N, Mask, Shift, X, AM))
2486         return false;
2487 
2488       // Try to fold the mask and shift into BEXTR and scale.
2489       if (!foldMaskedShiftToBEXTR(*CurDAG, N, Mask, Shift, X, AM, *Subtarget))
2490         return false;
2491     }
2492 
2493     // Try to swap the mask and shift to place shifts which can be done as
2494     // a scale on the outside of the mask.
2495     if (!foldMaskedShiftToScaledMask(*CurDAG, N, AM))
2496       return false;
2497 
2498     break;
2499   }
2500   case ISD::ZERO_EXTEND: {
2501     // Try to widen a zexted shift left to the same size as its use, so we can
2502     // match the shift as a scale factor.
2503     if (AM.IndexReg.getNode() != nullptr || AM.Scale != 1)
2504       break;
2505 
2506     // Peek through mask: zext(and(shl(x,c1),c2))
2507     SDValue Src = N.getOperand(0);
2508     APInt Mask = APInt::getAllOnes(Src.getScalarValueSizeInBits());
2509     if (Src.getOpcode() == ISD::AND && Src.hasOneUse())
2510       if (auto *MaskC = dyn_cast<ConstantSDNode>(Src.getOperand(1))) {
2511         Mask = MaskC->getAPIntValue();
2512         Src = Src.getOperand(0);
2513       }
2514 
2515     if (Src.getOpcode() == ISD::SHL && Src.hasOneUse()) {
2516       // Give up if the shift is not a valid scale factor [1,2,3].
2517       SDValue ShlSrc = Src.getOperand(0);
2518       SDValue ShlAmt = Src.getOperand(1);
2519       auto *ShAmtC = dyn_cast<ConstantSDNode>(ShlAmt);
2520       if (!ShAmtC)
2521         break;
2522       unsigned ShAmtV = ShAmtC->getZExtValue();
2523       if (ShAmtV > 3)
2524         break;
2525 
2526       // The narrow shift must only shift out zero bits (it must be 'nuw').
2527       // That makes it safe to widen to the destination type.
2528       APInt HighZeros =
2529           APInt::getHighBitsSet(ShlSrc.getValueSizeInBits(), ShAmtV);
2530       if (!CurDAG->MaskedValueIsZero(ShlSrc, HighZeros & Mask))
2531         break;
2532 
2533       // zext (shl nuw i8 %x, C1) to i32
2534       // --> shl (zext i8 %x to i32), (zext C1)
2535       // zext (and (shl nuw i8 %x, C1), C2) to i32
2536       // --> shl (zext i8 (and %x, C2 >> C1) to i32), (zext C1)
2537       MVT SrcVT = ShlSrc.getSimpleValueType();
2538       MVT VT = N.getSimpleValueType();
2539       SDLoc DL(N);
2540 
2541       SDValue Res = ShlSrc;
2542       if (!Mask.isAllOnes()) {
2543         Res = CurDAG->getConstant(Mask.lshr(ShAmtV), DL, SrcVT);
2544         insertDAGNode(*CurDAG, N, Res);
2545         Res = CurDAG->getNode(ISD::AND, DL, SrcVT, ShlSrc, Res);
2546         insertDAGNode(*CurDAG, N, Res);
2547       }
2548       SDValue Zext = CurDAG->getNode(ISD::ZERO_EXTEND, DL, VT, Res);
2549       insertDAGNode(*CurDAG, N, Zext);
2550       SDValue NewShl = CurDAG->getNode(ISD::SHL, DL, VT, Zext, ShlAmt);
2551       insertDAGNode(*CurDAG, N, NewShl);
2552 
2553       // Convert the shift to scale factor.
2554       AM.Scale = 1 << ShAmtV;
2555       AM.IndexReg = Zext;
2556 
2557       CurDAG->ReplaceAllUsesWith(N, NewShl);
2558       CurDAG->RemoveDeadNode(N.getNode());
2559       return false;
2560     }
2561 
2562     // Try to fold the mask and shift into an extract and scale.
2563     if (Src.getOpcode() == ISD::SRL && !Mask.isAllOnes() &&
2564         !foldMaskAndShiftToExtract(*CurDAG, N, Mask.getZExtValue(), Src,
2565                                    Src.getOperand(0), AM))
2566       return false;
2567 
2568     break;
2569   }
2570   }
2571 
2572   return matchAddressBase(N, AM);
2573 }
2574 
2575 /// Helper for MatchAddress. Add the specified node to the
2576 /// specified addressing mode without any further recursion.
2577 bool X86DAGToDAGISel::matchAddressBase(SDValue N, X86ISelAddressMode &AM) {
2578   // Is the base register already occupied?
2579   if (AM.BaseType != X86ISelAddressMode::RegBase || AM.Base_Reg.getNode()) {
2580     // If so, check to see if the scale index register is set.
2581     if (!AM.IndexReg.getNode()) {
2582       AM.IndexReg = N;
2583       AM.Scale = 1;
2584       return false;
2585     }
2586 
2587     // Otherwise, we cannot select it.
2588     return true;
2589   }
2590 
2591   // Default, generate it as a register.
2592   AM.BaseType = X86ISelAddressMode::RegBase;
2593   AM.Base_Reg = N;
2594   return false;
2595 }
2596 
2597 bool X86DAGToDAGISel::matchVectorAddressRecursively(SDValue N,
2598                                                     X86ISelAddressMode &AM,
2599                                                     unsigned Depth) {
2600   SDLoc dl(N);
2601   LLVM_DEBUG({
2602     dbgs() << "MatchVectorAddress: ";
2603     AM.dump(CurDAG);
2604   });
2605   // Limit recursion.
2606   if (Depth > 5)
2607     return matchAddressBase(N, AM);
2608 
2609   // TODO: Support other operations.
2610   switch (N.getOpcode()) {
2611   case ISD::Constant: {
2612     uint64_t Val = cast<ConstantSDNode>(N)->getSExtValue();
2613     if (!foldOffsetIntoAddress(Val, AM))
2614       return false;
2615     break;
2616   }
2617   case X86ISD::Wrapper:
2618     if (!matchWrapper(N, AM))
2619       return false;
2620     break;
2621   case ISD::ADD: {
2622     // Add an artificial use to this node so that we can keep track of
2623     // it if it gets CSE'd with a different node.
2624     HandleSDNode Handle(N);
2625 
2626     X86ISelAddressMode Backup = AM;
2627     if (!matchVectorAddressRecursively(N.getOperand(0), AM, Depth + 1) &&
2628         !matchVectorAddressRecursively(Handle.getValue().getOperand(1), AM,
2629                                        Depth + 1))
2630       return false;
2631     AM = Backup;
2632 
2633     // Try again after commuting the operands.
2634     if (!matchVectorAddressRecursively(Handle.getValue().getOperand(1), AM,
2635                                        Depth + 1) &&
2636         !matchVectorAddressRecursively(Handle.getValue().getOperand(0), AM,
2637                                        Depth + 1))
2638       return false;
2639     AM = Backup;
2640 
2641     N = Handle.getValue();
2642     break;
2643   }
2644   }
2645 
2646   return matchAddressBase(N, AM);
2647 }
2648 
2649 /// Helper for selectVectorAddr. Handles things that can be folded into a
2650 /// gather/scatter address. The index register and scale should have already
2651 /// been handled.
2652 bool X86DAGToDAGISel::matchVectorAddress(SDValue N, X86ISelAddressMode &AM) {
2653   return matchVectorAddressRecursively(N, AM, 0);
2654 }
2655 
2656 bool X86DAGToDAGISel::selectVectorAddr(MemSDNode *Parent, SDValue BasePtr,
2657                                        SDValue IndexOp, SDValue ScaleOp,
2658                                        SDValue &Base, SDValue &Scale,
2659                                        SDValue &Index, SDValue &Disp,
2660                                        SDValue &Segment) {
2661   X86ISelAddressMode AM;
2662   AM.IndexReg = IndexOp;
2663   AM.Scale = cast<ConstantSDNode>(ScaleOp)->getZExtValue();
2664 
2665   unsigned AddrSpace = Parent->getPointerInfo().getAddrSpace();
2666   if (AddrSpace == X86AS::GS)
2667     AM.Segment = CurDAG->getRegister(X86::GS, MVT::i16);
2668   if (AddrSpace == X86AS::FS)
2669     AM.Segment = CurDAG->getRegister(X86::FS, MVT::i16);
2670   if (AddrSpace == X86AS::SS)
2671     AM.Segment = CurDAG->getRegister(X86::SS, MVT::i16);
2672 
2673   SDLoc DL(BasePtr);
2674   MVT VT = BasePtr.getSimpleValueType();
2675 
2676   // Try to match into the base and displacement fields.
2677   if (matchVectorAddress(BasePtr, AM))
2678     return false;
2679 
2680   getAddressOperands(AM, DL, VT, Base, Scale, Index, Disp, Segment);
2681   return true;
2682 }
2683 
2684 /// Returns true if it is able to pattern match an addressing mode.
2685 /// It returns the operands which make up the maximal addressing mode it can
2686 /// match by reference.
2687 ///
2688 /// Parent is the parent node of the addr operand that is being matched.  It
2689 /// is always a load, store, atomic node, or null.  It is only null when
2690 /// checking memory operands for inline asm nodes.
2691 bool X86DAGToDAGISel::selectAddr(SDNode *Parent, SDValue N, SDValue &Base,
2692                                  SDValue &Scale, SDValue &Index,
2693                                  SDValue &Disp, SDValue &Segment) {
2694   X86ISelAddressMode AM;
2695 
2696   if (Parent &&
2697       // This list of opcodes are all the nodes that have an "addr:$ptr" operand
2698       // that are not a MemSDNode, and thus don't have proper addrspace info.
2699       Parent->getOpcode() != ISD::INTRINSIC_W_CHAIN && // unaligned loads, fixme
2700       Parent->getOpcode() != ISD::INTRINSIC_VOID && // nontemporal stores
2701       Parent->getOpcode() != X86ISD::TLSCALL && // Fixme
2702       Parent->getOpcode() != X86ISD::ENQCMD && // Fixme
2703       Parent->getOpcode() != X86ISD::ENQCMDS && // Fixme
2704       Parent->getOpcode() != X86ISD::EH_SJLJ_SETJMP && // setjmp
2705       Parent->getOpcode() != X86ISD::EH_SJLJ_LONGJMP) { // longjmp
2706     unsigned AddrSpace =
2707       cast<MemSDNode>(Parent)->getPointerInfo().getAddrSpace();
2708     if (AddrSpace == X86AS::GS)
2709       AM.Segment = CurDAG->getRegister(X86::GS, MVT::i16);
2710     if (AddrSpace == X86AS::FS)
2711       AM.Segment = CurDAG->getRegister(X86::FS, MVT::i16);
2712     if (AddrSpace == X86AS::SS)
2713       AM.Segment = CurDAG->getRegister(X86::SS, MVT::i16);
2714   }
2715 
2716   // Save the DL and VT before calling matchAddress, it can invalidate N.
2717   SDLoc DL(N);
2718   MVT VT = N.getSimpleValueType();
2719 
2720   if (matchAddress(N, AM))
2721     return false;
2722 
2723   getAddressOperands(AM, DL, VT, Base, Scale, Index, Disp, Segment);
2724   return true;
2725 }
2726 
2727 bool X86DAGToDAGISel::selectMOV64Imm32(SDValue N, SDValue &Imm) {
2728   // In static codegen with small code model, we can get the address of a label
2729   // into a register with 'movl'
2730   if (N->getOpcode() != X86ISD::Wrapper)
2731     return false;
2732 
2733   N = N.getOperand(0);
2734 
2735   // At least GNU as does not accept 'movl' for TPOFF relocations.
2736   // FIXME: We could use 'movl' when we know we are targeting MC.
2737   if (N->getOpcode() == ISD::TargetGlobalTLSAddress)
2738     return false;
2739 
2740   Imm = N;
2741   if (N->getOpcode() != ISD::TargetGlobalAddress)
2742     return TM.getCodeModel() == CodeModel::Small;
2743 
2744   std::optional<ConstantRange> CR =
2745       cast<GlobalAddressSDNode>(N)->getGlobal()->getAbsoluteSymbolRange();
2746   if (!CR)
2747     return TM.getCodeModel() == CodeModel::Small;
2748 
2749   return CR->getUnsignedMax().ult(1ull << 32);
2750 }
2751 
2752 bool X86DAGToDAGISel::selectLEA64_32Addr(SDValue N, SDValue &Base,
2753                                          SDValue &Scale, SDValue &Index,
2754                                          SDValue &Disp, SDValue &Segment) {
2755   // Save the debug loc before calling selectLEAAddr, in case it invalidates N.
2756   SDLoc DL(N);
2757 
2758   if (!selectLEAAddr(N, Base, Scale, Index, Disp, Segment))
2759     return false;
2760 
2761   auto *RN = dyn_cast<RegisterSDNode>(Base);
2762   if (RN && RN->getReg() == 0)
2763     Base = CurDAG->getRegister(0, MVT::i64);
2764   else if (Base.getValueType() == MVT::i32 && !isa<FrameIndexSDNode>(Base)) {
2765     // Base could already be %rip, particularly in the x32 ABI.
2766     SDValue ImplDef = SDValue(CurDAG->getMachineNode(X86::IMPLICIT_DEF, DL,
2767                                                      MVT::i64), 0);
2768     Base = CurDAG->getTargetInsertSubreg(X86::sub_32bit, DL, MVT::i64, ImplDef,
2769                                          Base);
2770   }
2771 
2772   RN = dyn_cast<RegisterSDNode>(Index);
2773   if (RN && RN->getReg() == 0)
2774     Index = CurDAG->getRegister(0, MVT::i64);
2775   else {
2776     assert(Index.getValueType() == MVT::i32 &&
2777            "Expect to be extending 32-bit registers for use in LEA");
2778     SDValue ImplDef = SDValue(CurDAG->getMachineNode(X86::IMPLICIT_DEF, DL,
2779                                                      MVT::i64), 0);
2780     Index = CurDAG->getTargetInsertSubreg(X86::sub_32bit, DL, MVT::i64, ImplDef,
2781                                           Index);
2782   }
2783 
2784   return true;
2785 }
2786 
2787 /// Calls SelectAddr and determines if the maximal addressing
2788 /// mode it matches can be cost effectively emitted as an LEA instruction.
2789 bool X86DAGToDAGISel::selectLEAAddr(SDValue N,
2790                                     SDValue &Base, SDValue &Scale,
2791                                     SDValue &Index, SDValue &Disp,
2792                                     SDValue &Segment) {
2793   X86ISelAddressMode AM;
2794 
2795   // Save the DL and VT before calling matchAddress, it can invalidate N.
2796   SDLoc DL(N);
2797   MVT VT = N.getSimpleValueType();
2798 
2799   // Set AM.Segment to prevent MatchAddress from using one. LEA doesn't support
2800   // segments.
2801   SDValue Copy = AM.Segment;
2802   SDValue T = CurDAG->getRegister(0, MVT::i32);
2803   AM.Segment = T;
2804   if (matchAddress(N, AM))
2805     return false;
2806   assert (T == AM.Segment);
2807   AM.Segment = Copy;
2808 
2809   unsigned Complexity = 0;
2810   if (AM.BaseType == X86ISelAddressMode::RegBase && AM.Base_Reg.getNode())
2811     Complexity = 1;
2812   else if (AM.BaseType == X86ISelAddressMode::FrameIndexBase)
2813     Complexity = 4;
2814 
2815   if (AM.IndexReg.getNode())
2816     Complexity++;
2817 
2818   // Don't match just leal(,%reg,2). It's cheaper to do addl %reg, %reg, or with
2819   // a simple shift.
2820   if (AM.Scale > 1)
2821     Complexity++;
2822 
2823   // FIXME: We are artificially lowering the criteria to turn ADD %reg, $GA
2824   // to a LEA. This is determined with some experimentation but is by no means
2825   // optimal (especially for code size consideration). LEA is nice because of
2826   // its three-address nature. Tweak the cost function again when we can run
2827   // convertToThreeAddress() at register allocation time.
2828   if (AM.hasSymbolicDisplacement()) {
2829     // For X86-64, always use LEA to materialize RIP-relative addresses.
2830     if (Subtarget->is64Bit())
2831       Complexity = 4;
2832     else
2833       Complexity += 2;
2834   }
2835 
2836   // Heuristic: try harder to form an LEA from ADD if the operands set flags.
2837   // Unlike ADD, LEA does not affect flags, so we will be less likely to require
2838   // duplicating flag-producing instructions later in the pipeline.
2839   if (N.getOpcode() == ISD::ADD) {
2840     auto isMathWithFlags = [](SDValue V) {
2841       switch (V.getOpcode()) {
2842       case X86ISD::ADD:
2843       case X86ISD::SUB:
2844       case X86ISD::ADC:
2845       case X86ISD::SBB:
2846       case X86ISD::SMUL:
2847       case X86ISD::UMUL:
2848       /* TODO: These opcodes can be added safely, but we may want to justify
2849                their inclusion for different reasons (better for reg-alloc).
2850       case X86ISD::OR:
2851       case X86ISD::XOR:
2852       case X86ISD::AND:
2853       */
2854         // Value 1 is the flag output of the node - verify it's not dead.
2855         return !SDValue(V.getNode(), 1).use_empty();
2856       default:
2857         return false;
2858       }
2859     };
2860     // TODO: We might want to factor in whether there's a load folding
2861     // opportunity for the math op that disappears with LEA.
2862     if (isMathWithFlags(N.getOperand(0)) || isMathWithFlags(N.getOperand(1)))
2863       Complexity++;
2864   }
2865 
2866   if (AM.Disp)
2867     Complexity++;
2868 
2869   // If it isn't worth using an LEA, reject it.
2870   if (Complexity <= 2)
2871     return false;
2872 
2873   getAddressOperands(AM, DL, VT, Base, Scale, Index, Disp, Segment);
2874   return true;
2875 }
2876 
2877 /// This is only run on TargetGlobalTLSAddress nodes.
2878 bool X86DAGToDAGISel::selectTLSADDRAddr(SDValue N, SDValue &Base,
2879                                         SDValue &Scale, SDValue &Index,
2880                                         SDValue &Disp, SDValue &Segment) {
2881   assert(N.getOpcode() == ISD::TargetGlobalTLSAddress);
2882   auto *GA = cast<GlobalAddressSDNode>(N);
2883 
2884   X86ISelAddressMode AM;
2885   AM.GV = GA->getGlobal();
2886   AM.Disp += GA->getOffset();
2887   AM.SymbolFlags = GA->getTargetFlags();
2888 
2889   if (Subtarget->is32Bit()) {
2890     AM.Scale = 1;
2891     AM.IndexReg = CurDAG->getRegister(X86::EBX, MVT::i32);
2892   }
2893 
2894   MVT VT = N.getSimpleValueType();
2895   getAddressOperands(AM, SDLoc(N), VT, Base, Scale, Index, Disp, Segment);
2896   return true;
2897 }
2898 
2899 bool X86DAGToDAGISel::selectRelocImm(SDValue N, SDValue &Op) {
2900   // Keep track of the original value type and whether this value was
2901   // truncated. If we see a truncation from pointer type to VT that truncates
2902   // bits that are known to be zero, we can use a narrow reference.
2903   EVT VT = N.getValueType();
2904   bool WasTruncated = false;
2905   if (N.getOpcode() == ISD::TRUNCATE) {
2906     WasTruncated = true;
2907     N = N.getOperand(0);
2908   }
2909 
2910   if (N.getOpcode() != X86ISD::Wrapper)
2911     return false;
2912 
2913   // We can only use non-GlobalValues as immediates if they were not truncated,
2914   // as we do not have any range information. If we have a GlobalValue and the
2915   // address was not truncated, we can select it as an operand directly.
2916   unsigned Opc = N.getOperand(0)->getOpcode();
2917   if (Opc != ISD::TargetGlobalAddress || !WasTruncated) {
2918     Op = N.getOperand(0);
2919     // We can only select the operand directly if we didn't have to look past a
2920     // truncate.
2921     return !WasTruncated;
2922   }
2923 
2924   // Check that the global's range fits into VT.
2925   auto *GA = cast<GlobalAddressSDNode>(N.getOperand(0));
2926   std::optional<ConstantRange> CR = GA->getGlobal()->getAbsoluteSymbolRange();
2927   if (!CR || CR->getUnsignedMax().uge(1ull << VT.getSizeInBits()))
2928     return false;
2929 
2930   // Okay, we can use a narrow reference.
2931   Op = CurDAG->getTargetGlobalAddress(GA->getGlobal(), SDLoc(N), VT,
2932                                       GA->getOffset(), GA->getTargetFlags());
2933   return true;
2934 }
2935 
2936 bool X86DAGToDAGISel::tryFoldLoad(SDNode *Root, SDNode *P, SDValue N,
2937                                   SDValue &Base, SDValue &Scale,
2938                                   SDValue &Index, SDValue &Disp,
2939                                   SDValue &Segment) {
2940   assert(Root && P && "Unknown root/parent nodes");
2941   if (!ISD::isNON_EXTLoad(N.getNode()) ||
2942       !IsProfitableToFold(N, P, Root) ||
2943       !IsLegalToFold(N, P, Root, OptLevel))
2944     return false;
2945 
2946   return selectAddr(N.getNode(),
2947                     N.getOperand(1), Base, Scale, Index, Disp, Segment);
2948 }
2949 
2950 bool X86DAGToDAGISel::tryFoldBroadcast(SDNode *Root, SDNode *P, SDValue N,
2951                                        SDValue &Base, SDValue &Scale,
2952                                        SDValue &Index, SDValue &Disp,
2953                                        SDValue &Segment) {
2954   assert(Root && P && "Unknown root/parent nodes");
2955   if (N->getOpcode() != X86ISD::VBROADCAST_LOAD ||
2956       !IsProfitableToFold(N, P, Root) ||
2957       !IsLegalToFold(N, P, Root, OptLevel))
2958     return false;
2959 
2960   return selectAddr(N.getNode(),
2961                     N.getOperand(1), Base, Scale, Index, Disp, Segment);
2962 }
2963 
2964 /// Return an SDNode that returns the value of the global base register.
2965 /// Output instructions required to initialize the global base register,
2966 /// if necessary.
2967 SDNode *X86DAGToDAGISel::getGlobalBaseReg() {
2968   unsigned GlobalBaseReg = getInstrInfo()->getGlobalBaseReg(MF);
2969   auto &DL = MF->getDataLayout();
2970   return CurDAG->getRegister(GlobalBaseReg, TLI->getPointerTy(DL)).getNode();
2971 }
2972 
2973 bool X86DAGToDAGISel::isSExtAbsoluteSymbolRef(unsigned Width, SDNode *N) const {
2974   if (N->getOpcode() == ISD::TRUNCATE)
2975     N = N->getOperand(0).getNode();
2976   if (N->getOpcode() != X86ISD::Wrapper)
2977     return false;
2978 
2979   auto *GA = dyn_cast<GlobalAddressSDNode>(N->getOperand(0));
2980   if (!GA)
2981     return false;
2982 
2983   std::optional<ConstantRange> CR = GA->getGlobal()->getAbsoluteSymbolRange();
2984   if (!CR)
2985     return Width == 32 && TM.getCodeModel() == CodeModel::Small;
2986 
2987   return CR->getSignedMin().sge(-1ull << Width) &&
2988          CR->getSignedMax().slt(1ull << Width);
2989 }
2990 
2991 X86::CondCode X86DAGToDAGISel::getCondFromNode(SDNode *N) const {
2992   assert(N->isMachineOpcode() && "Unexpected node");
2993   unsigned Opc = N->getMachineOpcode();
2994   const MCInstrDesc &MCID = getInstrInfo()->get(Opc);
2995   int CondNo = X86::getCondSrcNoFromDesc(MCID);
2996   if (CondNo < 0)
2997     return X86::COND_INVALID;
2998 
2999   return static_cast<X86::CondCode>(N->getConstantOperandVal(CondNo));
3000 }
3001 
3002 /// Test whether the given X86ISD::CMP node has any users that use a flag
3003 /// other than ZF.
3004 bool X86DAGToDAGISel::onlyUsesZeroFlag(SDValue Flags) const {
3005   // Examine each user of the node.
3006   for (SDNode::use_iterator UI = Flags->use_begin(), UE = Flags->use_end();
3007          UI != UE; ++UI) {
3008     // Only check things that use the flags.
3009     if (UI.getUse().getResNo() != Flags.getResNo())
3010       continue;
3011     // Only examine CopyToReg uses that copy to EFLAGS.
3012     if (UI->getOpcode() != ISD::CopyToReg ||
3013         cast<RegisterSDNode>(UI->getOperand(1))->getReg() != X86::EFLAGS)
3014       return false;
3015     // Examine each user of the CopyToReg use.
3016     for (SDNode::use_iterator FlagUI = UI->use_begin(),
3017            FlagUE = UI->use_end(); FlagUI != FlagUE; ++FlagUI) {
3018       // Only examine the Flag result.
3019       if (FlagUI.getUse().getResNo() != 1) continue;
3020       // Anything unusual: assume conservatively.
3021       if (!FlagUI->isMachineOpcode()) return false;
3022       // Examine the condition code of the user.
3023       X86::CondCode CC = getCondFromNode(*FlagUI);
3024 
3025       switch (CC) {
3026       // Comparisons which only use the zero flag.
3027       case X86::COND_E: case X86::COND_NE:
3028         continue;
3029       // Anything else: assume conservatively.
3030       default:
3031         return false;
3032       }
3033     }
3034   }
3035   return true;
3036 }
3037 
3038 /// Test whether the given X86ISD::CMP node has any uses which require the SF
3039 /// flag to be accurate.
3040 bool X86DAGToDAGISel::hasNoSignFlagUses(SDValue Flags) const {
3041   // Examine each user of the node.
3042   for (SDNode::use_iterator UI = Flags->use_begin(), UE = Flags->use_end();
3043          UI != UE; ++UI) {
3044     // Only check things that use the flags.
3045     if (UI.getUse().getResNo() != Flags.getResNo())
3046       continue;
3047     // Only examine CopyToReg uses that copy to EFLAGS.
3048     if (UI->getOpcode() != ISD::CopyToReg ||
3049         cast<RegisterSDNode>(UI->getOperand(1))->getReg() != X86::EFLAGS)
3050       return false;
3051     // Examine each user of the CopyToReg use.
3052     for (SDNode::use_iterator FlagUI = UI->use_begin(),
3053            FlagUE = UI->use_end(); FlagUI != FlagUE; ++FlagUI) {
3054       // Only examine the Flag result.
3055       if (FlagUI.getUse().getResNo() != 1) continue;
3056       // Anything unusual: assume conservatively.
3057       if (!FlagUI->isMachineOpcode()) return false;
3058       // Examine the condition code of the user.
3059       X86::CondCode CC = getCondFromNode(*FlagUI);
3060 
3061       switch (CC) {
3062       // Comparisons which don't examine the SF flag.
3063       case X86::COND_A: case X86::COND_AE:
3064       case X86::COND_B: case X86::COND_BE:
3065       case X86::COND_E: case X86::COND_NE:
3066       case X86::COND_O: case X86::COND_NO:
3067       case X86::COND_P: case X86::COND_NP:
3068         continue;
3069       // Anything else: assume conservatively.
3070       default:
3071         return false;
3072       }
3073     }
3074   }
3075   return true;
3076 }
3077 
3078 static bool mayUseCarryFlag(X86::CondCode CC) {
3079   switch (CC) {
3080   // Comparisons which don't examine the CF flag.
3081   case X86::COND_O: case X86::COND_NO:
3082   case X86::COND_E: case X86::COND_NE:
3083   case X86::COND_S: case X86::COND_NS:
3084   case X86::COND_P: case X86::COND_NP:
3085   case X86::COND_L: case X86::COND_GE:
3086   case X86::COND_G: case X86::COND_LE:
3087     return false;
3088   // Anything else: assume conservatively.
3089   default:
3090     return true;
3091   }
3092 }
3093 
3094 /// Test whether the given node which sets flags has any uses which require the
3095 /// CF flag to be accurate.
3096  bool X86DAGToDAGISel::hasNoCarryFlagUses(SDValue Flags) const {
3097   // Examine each user of the node.
3098   for (SDNode::use_iterator UI = Flags->use_begin(), UE = Flags->use_end();
3099          UI != UE; ++UI) {
3100     // Only check things that use the flags.
3101     if (UI.getUse().getResNo() != Flags.getResNo())
3102       continue;
3103 
3104     unsigned UIOpc = UI->getOpcode();
3105 
3106     if (UIOpc == ISD::CopyToReg) {
3107       // Only examine CopyToReg uses that copy to EFLAGS.
3108       if (cast<RegisterSDNode>(UI->getOperand(1))->getReg() != X86::EFLAGS)
3109         return false;
3110       // Examine each user of the CopyToReg use.
3111       for (SDNode::use_iterator FlagUI = UI->use_begin(), FlagUE = UI->use_end();
3112            FlagUI != FlagUE; ++FlagUI) {
3113         // Only examine the Flag result.
3114         if (FlagUI.getUse().getResNo() != 1)
3115           continue;
3116         // Anything unusual: assume conservatively.
3117         if (!FlagUI->isMachineOpcode())
3118           return false;
3119         // Examine the condition code of the user.
3120         X86::CondCode CC = getCondFromNode(*FlagUI);
3121 
3122         if (mayUseCarryFlag(CC))
3123           return false;
3124       }
3125 
3126       // This CopyToReg is ok. Move on to the next user.
3127       continue;
3128     }
3129 
3130     // This might be an unselected node. So look for the pre-isel opcodes that
3131     // use flags.
3132     unsigned CCOpNo;
3133     switch (UIOpc) {
3134     default:
3135       // Something unusual. Be conservative.
3136       return false;
3137     case X86ISD::SETCC:       CCOpNo = 0; break;
3138     case X86ISD::SETCC_CARRY: CCOpNo = 0; break;
3139     case X86ISD::CMOV:        CCOpNo = 2; break;
3140     case X86ISD::BRCOND:      CCOpNo = 2; break;
3141     }
3142 
3143     X86::CondCode CC = (X86::CondCode)UI->getConstantOperandVal(CCOpNo);
3144     if (mayUseCarryFlag(CC))
3145       return false;
3146   }
3147   return true;
3148 }
3149 
3150 /// Check whether or not the chain ending in StoreNode is suitable for doing
3151 /// the {load; op; store} to modify transformation.
3152 static bool isFusableLoadOpStorePattern(StoreSDNode *StoreNode,
3153                                         SDValue StoredVal, SelectionDAG *CurDAG,
3154                                         unsigned LoadOpNo,
3155                                         LoadSDNode *&LoadNode,
3156                                         SDValue &InputChain) {
3157   // Is the stored value result 0 of the operation?
3158   if (StoredVal.getResNo() != 0) return false;
3159 
3160   // Are there other uses of the operation other than the store?
3161   if (!StoredVal.getNode()->hasNUsesOfValue(1, 0)) return false;
3162 
3163   // Is the store non-extending and non-indexed?
3164   if (!ISD::isNormalStore(StoreNode) || StoreNode->isNonTemporal())
3165     return false;
3166 
3167   SDValue Load = StoredVal->getOperand(LoadOpNo);
3168   // Is the stored value a non-extending and non-indexed load?
3169   if (!ISD::isNormalLoad(Load.getNode())) return false;
3170 
3171   // Return LoadNode by reference.
3172   LoadNode = cast<LoadSDNode>(Load);
3173 
3174   // Is store the only read of the loaded value?
3175   if (!Load.hasOneUse())
3176     return false;
3177 
3178   // Is the address of the store the same as the load?
3179   if (LoadNode->getBasePtr() != StoreNode->getBasePtr() ||
3180       LoadNode->getOffset() != StoreNode->getOffset())
3181     return false;
3182 
3183   bool FoundLoad = false;
3184   SmallVector<SDValue, 4> ChainOps;
3185   SmallVector<const SDNode *, 4> LoopWorklist;
3186   SmallPtrSet<const SDNode *, 16> Visited;
3187   const unsigned int Max = 1024;
3188 
3189   //  Visualization of Load-Op-Store fusion:
3190   // -------------------------
3191   // Legend:
3192   //    *-lines = Chain operand dependencies.
3193   //    |-lines = Normal operand dependencies.
3194   //    Dependencies flow down and right. n-suffix references multiple nodes.
3195   //
3196   //        C                        Xn  C
3197   //        *                         *  *
3198   //        *                          * *
3199   //  Xn  A-LD    Yn                    TF         Yn
3200   //   *    * \   |                       *        |
3201   //    *   *  \  |                        *       |
3202   //     *  *   \ |             =>       A--LD_OP_ST
3203   //      * *    \|                                 \
3204   //       TF    OP                                  \
3205   //         *   | \                                  Zn
3206   //          *  |  \
3207   //         A-ST    Zn
3208   //
3209 
3210   // This merge induced dependences from: #1: Xn -> LD, OP, Zn
3211   //                                      #2: Yn -> LD
3212   //                                      #3: ST -> Zn
3213 
3214   // Ensure the transform is safe by checking for the dual
3215   // dependencies to make sure we do not induce a loop.
3216 
3217   // As LD is a predecessor to both OP and ST we can do this by checking:
3218   //  a). if LD is a predecessor to a member of Xn or Yn.
3219   //  b). if a Zn is a predecessor to ST.
3220 
3221   // However, (b) can only occur through being a chain predecessor to
3222   // ST, which is the same as Zn being a member or predecessor of Xn,
3223   // which is a subset of LD being a predecessor of Xn. So it's
3224   // subsumed by check (a).
3225 
3226   SDValue Chain = StoreNode->getChain();
3227 
3228   // Gather X elements in ChainOps.
3229   if (Chain == Load.getValue(1)) {
3230     FoundLoad = true;
3231     ChainOps.push_back(Load.getOperand(0));
3232   } else if (Chain.getOpcode() == ISD::TokenFactor) {
3233     for (unsigned i = 0, e = Chain.getNumOperands(); i != e; ++i) {
3234       SDValue Op = Chain.getOperand(i);
3235       if (Op == Load.getValue(1)) {
3236         FoundLoad = true;
3237         // Drop Load, but keep its chain. No cycle check necessary.
3238         ChainOps.push_back(Load.getOperand(0));
3239         continue;
3240       }
3241       LoopWorklist.push_back(Op.getNode());
3242       ChainOps.push_back(Op);
3243     }
3244   }
3245 
3246   if (!FoundLoad)
3247     return false;
3248 
3249   // Worklist is currently Xn. Add Yn to worklist.
3250   for (SDValue Op : StoredVal->ops())
3251     if (Op.getNode() != LoadNode)
3252       LoopWorklist.push_back(Op.getNode());
3253 
3254   // Check (a) if Load is a predecessor to Xn + Yn
3255   if (SDNode::hasPredecessorHelper(Load.getNode(), Visited, LoopWorklist, Max,
3256                                    true))
3257     return false;
3258 
3259   InputChain =
3260       CurDAG->getNode(ISD::TokenFactor, SDLoc(Chain), MVT::Other, ChainOps);
3261   return true;
3262 }
3263 
3264 // Change a chain of {load; op; store} of the same value into a simple op
3265 // through memory of that value, if the uses of the modified value and its
3266 // address are suitable.
3267 //
3268 // The tablegen pattern memory operand pattern is currently not able to match
3269 // the case where the EFLAGS on the original operation are used.
3270 //
3271 // To move this to tablegen, we'll need to improve tablegen to allow flags to
3272 // be transferred from a node in the pattern to the result node, probably with
3273 // a new keyword. For example, we have this
3274 // def DEC64m : RI<0xFF, MRM1m, (outs), (ins i64mem:$dst), "dec{q}\t$dst",
3275 //  [(store (add (loadi64 addr:$dst), -1), addr:$dst),
3276 //   (implicit EFLAGS)]>;
3277 // but maybe need something like this
3278 // def DEC64m : RI<0xFF, MRM1m, (outs), (ins i64mem:$dst), "dec{q}\t$dst",
3279 //  [(store (add (loadi64 addr:$dst), -1), addr:$dst),
3280 //   (transferrable EFLAGS)]>;
3281 //
3282 // Until then, we manually fold these and instruction select the operation
3283 // here.
3284 bool X86DAGToDAGISel::foldLoadStoreIntoMemOperand(SDNode *Node) {
3285   auto *StoreNode = cast<StoreSDNode>(Node);
3286   SDValue StoredVal = StoreNode->getOperand(1);
3287   unsigned Opc = StoredVal->getOpcode();
3288 
3289   // Before we try to select anything, make sure this is memory operand size
3290   // and opcode we can handle. Note that this must match the code below that
3291   // actually lowers the opcodes.
3292   EVT MemVT = StoreNode->getMemoryVT();
3293   if (MemVT != MVT::i64 && MemVT != MVT::i32 && MemVT != MVT::i16 &&
3294       MemVT != MVT::i8)
3295     return false;
3296 
3297   bool IsCommutable = false;
3298   bool IsNegate = false;
3299   switch (Opc) {
3300   default:
3301     return false;
3302   case X86ISD::SUB:
3303     IsNegate = isNullConstant(StoredVal.getOperand(0));
3304     break;
3305   case X86ISD::SBB:
3306     break;
3307   case X86ISD::ADD:
3308   case X86ISD::ADC:
3309   case X86ISD::AND:
3310   case X86ISD::OR:
3311   case X86ISD::XOR:
3312     IsCommutable = true;
3313     break;
3314   }
3315 
3316   unsigned LoadOpNo = IsNegate ? 1 : 0;
3317   LoadSDNode *LoadNode = nullptr;
3318   SDValue InputChain;
3319   if (!isFusableLoadOpStorePattern(StoreNode, StoredVal, CurDAG, LoadOpNo,
3320                                    LoadNode, InputChain)) {
3321     if (!IsCommutable)
3322       return false;
3323 
3324     // This operation is commutable, try the other operand.
3325     LoadOpNo = 1;
3326     if (!isFusableLoadOpStorePattern(StoreNode, StoredVal, CurDAG, LoadOpNo,
3327                                      LoadNode, InputChain))
3328       return false;
3329   }
3330 
3331   SDValue Base, Scale, Index, Disp, Segment;
3332   if (!selectAddr(LoadNode, LoadNode->getBasePtr(), Base, Scale, Index, Disp,
3333                   Segment))
3334     return false;
3335 
3336   auto SelectOpcode = [&](unsigned Opc64, unsigned Opc32, unsigned Opc16,
3337                           unsigned Opc8) {
3338     switch (MemVT.getSimpleVT().SimpleTy) {
3339     case MVT::i64:
3340       return Opc64;
3341     case MVT::i32:
3342       return Opc32;
3343     case MVT::i16:
3344       return Opc16;
3345     case MVT::i8:
3346       return Opc8;
3347     default:
3348       llvm_unreachable("Invalid size!");
3349     }
3350   };
3351 
3352   MachineSDNode *Result;
3353   switch (Opc) {
3354   case X86ISD::SUB:
3355     // Handle negate.
3356     if (IsNegate) {
3357       unsigned NewOpc = SelectOpcode(X86::NEG64m, X86::NEG32m, X86::NEG16m,
3358                                      X86::NEG8m);
3359       const SDValue Ops[] = {Base, Scale, Index, Disp, Segment, InputChain};
3360       Result = CurDAG->getMachineNode(NewOpc, SDLoc(Node), MVT::i32,
3361                                       MVT::Other, Ops);
3362       break;
3363     }
3364    [[fallthrough]];
3365   case X86ISD::ADD:
3366     // Try to match inc/dec.
3367     if (!Subtarget->slowIncDec() || CurDAG->shouldOptForSize()) {
3368       bool IsOne = isOneConstant(StoredVal.getOperand(1));
3369       bool IsNegOne = isAllOnesConstant(StoredVal.getOperand(1));
3370       // ADD/SUB with 1/-1 and carry flag isn't used can use inc/dec.
3371       if ((IsOne || IsNegOne) && hasNoCarryFlagUses(StoredVal.getValue(1))) {
3372         unsigned NewOpc =
3373           ((Opc == X86ISD::ADD) == IsOne)
3374               ? SelectOpcode(X86::INC64m, X86::INC32m, X86::INC16m, X86::INC8m)
3375               : SelectOpcode(X86::DEC64m, X86::DEC32m, X86::DEC16m, X86::DEC8m);
3376         const SDValue Ops[] = {Base, Scale, Index, Disp, Segment, InputChain};
3377         Result = CurDAG->getMachineNode(NewOpc, SDLoc(Node), MVT::i32,
3378                                         MVT::Other, Ops);
3379         break;
3380       }
3381     }
3382     [[fallthrough]];
3383   case X86ISD::ADC:
3384   case X86ISD::SBB:
3385   case X86ISD::AND:
3386   case X86ISD::OR:
3387   case X86ISD::XOR: {
3388     auto SelectRegOpcode = [SelectOpcode](unsigned Opc) {
3389       switch (Opc) {
3390       case X86ISD::ADD:
3391         return SelectOpcode(X86::ADD64mr, X86::ADD32mr, X86::ADD16mr,
3392                             X86::ADD8mr);
3393       case X86ISD::ADC:
3394         return SelectOpcode(X86::ADC64mr, X86::ADC32mr, X86::ADC16mr,
3395                             X86::ADC8mr);
3396       case X86ISD::SUB:
3397         return SelectOpcode(X86::SUB64mr, X86::SUB32mr, X86::SUB16mr,
3398                             X86::SUB8mr);
3399       case X86ISD::SBB:
3400         return SelectOpcode(X86::SBB64mr, X86::SBB32mr, X86::SBB16mr,
3401                             X86::SBB8mr);
3402       case X86ISD::AND:
3403         return SelectOpcode(X86::AND64mr, X86::AND32mr, X86::AND16mr,
3404                             X86::AND8mr);
3405       case X86ISD::OR:
3406         return SelectOpcode(X86::OR64mr, X86::OR32mr, X86::OR16mr, X86::OR8mr);
3407       case X86ISD::XOR:
3408         return SelectOpcode(X86::XOR64mr, X86::XOR32mr, X86::XOR16mr,
3409                             X86::XOR8mr);
3410       default:
3411         llvm_unreachable("Invalid opcode!");
3412       }
3413     };
3414     auto SelectImmOpcode = [SelectOpcode](unsigned Opc) {
3415       switch (Opc) {
3416       case X86ISD::ADD:
3417         return SelectOpcode(X86::ADD64mi32, X86::ADD32mi, X86::ADD16mi,
3418                             X86::ADD8mi);
3419       case X86ISD::ADC:
3420         return SelectOpcode(X86::ADC64mi32, X86::ADC32mi, X86::ADC16mi,
3421                             X86::ADC8mi);
3422       case X86ISD::SUB:
3423         return SelectOpcode(X86::SUB64mi32, X86::SUB32mi, X86::SUB16mi,
3424                             X86::SUB8mi);
3425       case X86ISD::SBB:
3426         return SelectOpcode(X86::SBB64mi32, X86::SBB32mi, X86::SBB16mi,
3427                             X86::SBB8mi);
3428       case X86ISD::AND:
3429         return SelectOpcode(X86::AND64mi32, X86::AND32mi, X86::AND16mi,
3430                             X86::AND8mi);
3431       case X86ISD::OR:
3432         return SelectOpcode(X86::OR64mi32, X86::OR32mi, X86::OR16mi,
3433                             X86::OR8mi);
3434       case X86ISD::XOR:
3435         return SelectOpcode(X86::XOR64mi32, X86::XOR32mi, X86::XOR16mi,
3436                             X86::XOR8mi);
3437       default:
3438         llvm_unreachable("Invalid opcode!");
3439       }
3440     };
3441 
3442     unsigned NewOpc = SelectRegOpcode(Opc);
3443     SDValue Operand = StoredVal->getOperand(1-LoadOpNo);
3444 
3445     // See if the operand is a constant that we can fold into an immediate
3446     // operand.
3447     if (auto *OperandC = dyn_cast<ConstantSDNode>(Operand)) {
3448       int64_t OperandV = OperandC->getSExtValue();
3449 
3450       // Check if we can shrink the operand enough to fit in an immediate (or
3451       // fit into a smaller immediate) by negating it and switching the
3452       // operation.
3453       if ((Opc == X86ISD::ADD || Opc == X86ISD::SUB) &&
3454           ((MemVT != MVT::i8 && !isInt<8>(OperandV) && isInt<8>(-OperandV)) ||
3455            (MemVT == MVT::i64 && !isInt<32>(OperandV) &&
3456             isInt<32>(-OperandV))) &&
3457           hasNoCarryFlagUses(StoredVal.getValue(1))) {
3458         OperandV = -OperandV;
3459         Opc = Opc == X86ISD::ADD ? X86ISD::SUB : X86ISD::ADD;
3460       }
3461 
3462       if (MemVT != MVT::i64 || isInt<32>(OperandV)) {
3463         Operand = CurDAG->getTargetConstant(OperandV, SDLoc(Node), MemVT);
3464         NewOpc = SelectImmOpcode(Opc);
3465       }
3466     }
3467 
3468     if (Opc == X86ISD::ADC || Opc == X86ISD::SBB) {
3469       SDValue CopyTo =
3470           CurDAG->getCopyToReg(InputChain, SDLoc(Node), X86::EFLAGS,
3471                                StoredVal.getOperand(2), SDValue());
3472 
3473       const SDValue Ops[] = {Base,    Scale,   Index,  Disp,
3474                              Segment, Operand, CopyTo, CopyTo.getValue(1)};
3475       Result = CurDAG->getMachineNode(NewOpc, SDLoc(Node), MVT::i32, MVT::Other,
3476                                       Ops);
3477     } else {
3478       const SDValue Ops[] = {Base,    Scale,   Index,     Disp,
3479                              Segment, Operand, InputChain};
3480       Result = CurDAG->getMachineNode(NewOpc, SDLoc(Node), MVT::i32, MVT::Other,
3481                                       Ops);
3482     }
3483     break;
3484   }
3485   default:
3486     llvm_unreachable("Invalid opcode!");
3487   }
3488 
3489   MachineMemOperand *MemOps[] = {StoreNode->getMemOperand(),
3490                                  LoadNode->getMemOperand()};
3491   CurDAG->setNodeMemRefs(Result, MemOps);
3492 
3493   // Update Load Chain uses as well.
3494   ReplaceUses(SDValue(LoadNode, 1), SDValue(Result, 1));
3495   ReplaceUses(SDValue(StoreNode, 0), SDValue(Result, 1));
3496   ReplaceUses(SDValue(StoredVal.getNode(), 1), SDValue(Result, 0));
3497   CurDAG->RemoveDeadNode(Node);
3498   return true;
3499 }
3500 
3501 // See if this is an  X & Mask  that we can match to BEXTR/BZHI.
3502 // Where Mask is one of the following patterns:
3503 //   a) x &  (1 << nbits) - 1
3504 //   b) x & ~(-1 << nbits)
3505 //   c) x &  (-1 >> (32 - y))
3506 //   d) x << (32 - y) >> (32 - y)
3507 //   e) (1 << nbits) - 1
3508 bool X86DAGToDAGISel::matchBitExtract(SDNode *Node) {
3509   assert(
3510       (Node->getOpcode() == ISD::ADD || Node->getOpcode() == ISD::AND ||
3511        Node->getOpcode() == ISD::SRL) &&
3512       "Should be either an and-mask, or right-shift after clearing high bits.");
3513 
3514   // BEXTR is BMI instruction, BZHI is BMI2 instruction. We need at least one.
3515   if (!Subtarget->hasBMI() && !Subtarget->hasBMI2())
3516     return false;
3517 
3518   MVT NVT = Node->getSimpleValueType(0);
3519 
3520   // Only supported for 32 and 64 bits.
3521   if (NVT != MVT::i32 && NVT != MVT::i64)
3522     return false;
3523 
3524   SDValue NBits;
3525   bool NegateNBits;
3526 
3527   // If we have BMI2's BZHI, we are ok with muti-use patterns.
3528   // Else, if we only have BMI1's BEXTR, we require one-use.
3529   const bool AllowExtraUsesByDefault = Subtarget->hasBMI2();
3530   auto checkUses = [AllowExtraUsesByDefault](
3531                        SDValue Op, unsigned NUses,
3532                        std::optional<bool> AllowExtraUses) {
3533     return AllowExtraUses.value_or(AllowExtraUsesByDefault) ||
3534            Op.getNode()->hasNUsesOfValue(NUses, Op.getResNo());
3535   };
3536   auto checkOneUse = [checkUses](SDValue Op,
3537                                  std::optional<bool> AllowExtraUses =
3538                                      std::nullopt) {
3539     return checkUses(Op, 1, AllowExtraUses);
3540   };
3541   auto checkTwoUse = [checkUses](SDValue Op,
3542                                  std::optional<bool> AllowExtraUses =
3543                                      std::nullopt) {
3544     return checkUses(Op, 2, AllowExtraUses);
3545   };
3546 
3547   auto peekThroughOneUseTruncation = [checkOneUse](SDValue V) {
3548     if (V->getOpcode() == ISD::TRUNCATE && checkOneUse(V)) {
3549       assert(V.getSimpleValueType() == MVT::i32 &&
3550              V.getOperand(0).getSimpleValueType() == MVT::i64 &&
3551              "Expected i64 -> i32 truncation");
3552       V = V.getOperand(0);
3553     }
3554     return V;
3555   };
3556 
3557   // a) x & ((1 << nbits) + (-1))
3558   auto matchPatternA = [checkOneUse, peekThroughOneUseTruncation, &NBits,
3559                         &NegateNBits](SDValue Mask) -> bool {
3560     // Match `add`. Must only have one use!
3561     if (Mask->getOpcode() != ISD::ADD || !checkOneUse(Mask))
3562       return false;
3563     // We should be adding all-ones constant (i.e. subtracting one.)
3564     if (!isAllOnesConstant(Mask->getOperand(1)))
3565       return false;
3566     // Match `1 << nbits`. Might be truncated. Must only have one use!
3567     SDValue M0 = peekThroughOneUseTruncation(Mask->getOperand(0));
3568     if (M0->getOpcode() != ISD::SHL || !checkOneUse(M0))
3569       return false;
3570     if (!isOneConstant(M0->getOperand(0)))
3571       return false;
3572     NBits = M0->getOperand(1);
3573     NegateNBits = false;
3574     return true;
3575   };
3576 
3577   auto isAllOnes = [this, peekThroughOneUseTruncation, NVT](SDValue V) {
3578     V = peekThroughOneUseTruncation(V);
3579     return CurDAG->MaskedValueIsAllOnes(
3580         V, APInt::getLowBitsSet(V.getSimpleValueType().getSizeInBits(),
3581                                 NVT.getSizeInBits()));
3582   };
3583 
3584   // b) x & ~(-1 << nbits)
3585   auto matchPatternB = [checkOneUse, isAllOnes, peekThroughOneUseTruncation,
3586                         &NBits, &NegateNBits](SDValue Mask) -> bool {
3587     // Match `~()`. Must only have one use!
3588     if (Mask.getOpcode() != ISD::XOR || !checkOneUse(Mask))
3589       return false;
3590     // The -1 only has to be all-ones for the final Node's NVT.
3591     if (!isAllOnes(Mask->getOperand(1)))
3592       return false;
3593     // Match `-1 << nbits`. Might be truncated. Must only have one use!
3594     SDValue M0 = peekThroughOneUseTruncation(Mask->getOperand(0));
3595     if (M0->getOpcode() != ISD::SHL || !checkOneUse(M0))
3596       return false;
3597     // The -1 only has to be all-ones for the final Node's NVT.
3598     if (!isAllOnes(M0->getOperand(0)))
3599       return false;
3600     NBits = M0->getOperand(1);
3601     NegateNBits = false;
3602     return true;
3603   };
3604 
3605   // Try to match potentially-truncated shift amount as `(bitwidth - y)`,
3606   // or leave the shift amount as-is, but then we'll have to negate it.
3607   auto canonicalizeShiftAmt = [&NBits, &NegateNBits](SDValue ShiftAmt,
3608                                                      unsigned Bitwidth) {
3609     NBits = ShiftAmt;
3610     NegateNBits = true;
3611     // Skip over a truncate of the shift amount, if any.
3612     if (NBits.getOpcode() == ISD::TRUNCATE)
3613       NBits = NBits.getOperand(0);
3614     // Try to match the shift amount as (bitwidth - y). It should go away, too.
3615     // If it doesn't match, that's fine, we'll just negate it ourselves.
3616     if (NBits.getOpcode() != ISD::SUB)
3617       return;
3618     auto *V0 = dyn_cast<ConstantSDNode>(NBits.getOperand(0));
3619     if (!V0 || V0->getZExtValue() != Bitwidth)
3620       return;
3621     NBits = NBits.getOperand(1);
3622     NegateNBits = false;
3623   };
3624 
3625   // c) x &  (-1 >> z)  but then we'll have to subtract z from bitwidth
3626   //   or
3627   // c) x &  (-1 >> (32 - y))
3628   auto matchPatternC = [checkOneUse, peekThroughOneUseTruncation, &NegateNBits,
3629                         canonicalizeShiftAmt](SDValue Mask) -> bool {
3630     // The mask itself may be truncated.
3631     Mask = peekThroughOneUseTruncation(Mask);
3632     unsigned Bitwidth = Mask.getSimpleValueType().getSizeInBits();
3633     // Match `l>>`. Must only have one use!
3634     if (Mask.getOpcode() != ISD::SRL || !checkOneUse(Mask))
3635       return false;
3636     // We should be shifting truly all-ones constant.
3637     if (!isAllOnesConstant(Mask.getOperand(0)))
3638       return false;
3639     SDValue M1 = Mask.getOperand(1);
3640     // The shift amount should not be used externally.
3641     if (!checkOneUse(M1))
3642       return false;
3643     canonicalizeShiftAmt(M1, Bitwidth);
3644     // Pattern c. is non-canonical, and is expanded into pattern d. iff there
3645     // is no extra use of the mask. Clearly, there was one since we are here.
3646     // But at the same time, if we need to negate the shift amount,
3647     // then we don't want the mask to stick around, else it's unprofitable.
3648     return !NegateNBits;
3649   };
3650 
3651   SDValue X;
3652 
3653   // d) x << z >> z  but then we'll have to subtract z from bitwidth
3654   //   or
3655   // d) x << (32 - y) >> (32 - y)
3656   auto matchPatternD = [checkOneUse, checkTwoUse, canonicalizeShiftAmt,
3657                         AllowExtraUsesByDefault, &NegateNBits,
3658                         &X](SDNode *Node) -> bool {
3659     if (Node->getOpcode() != ISD::SRL)
3660       return false;
3661     SDValue N0 = Node->getOperand(0);
3662     if (N0->getOpcode() != ISD::SHL)
3663       return false;
3664     unsigned Bitwidth = N0.getSimpleValueType().getSizeInBits();
3665     SDValue N1 = Node->getOperand(1);
3666     SDValue N01 = N0->getOperand(1);
3667     // Both of the shifts must be by the exact same value.
3668     if (N1 != N01)
3669       return false;
3670     canonicalizeShiftAmt(N1, Bitwidth);
3671     // There should not be any external uses of the inner shift / shift amount.
3672     // Note that while we are generally okay with external uses given BMI2,
3673     // iff we need to negate the shift amount, we are not okay with extra uses.
3674     const bool AllowExtraUses = AllowExtraUsesByDefault && !NegateNBits;
3675     if (!checkOneUse(N0, AllowExtraUses) || !checkTwoUse(N1, AllowExtraUses))
3676       return false;
3677     X = N0->getOperand(0);
3678     return true;
3679   };
3680 
3681   auto matchLowBitMask = [matchPatternA, matchPatternB,
3682                           matchPatternC](SDValue Mask) -> bool {
3683     return matchPatternA(Mask) || matchPatternB(Mask) || matchPatternC(Mask);
3684   };
3685 
3686   if (Node->getOpcode() == ISD::AND) {
3687     X = Node->getOperand(0);
3688     SDValue Mask = Node->getOperand(1);
3689 
3690     if (matchLowBitMask(Mask)) {
3691       // Great.
3692     } else {
3693       std::swap(X, Mask);
3694       if (!matchLowBitMask(Mask))
3695         return false;
3696     }
3697   } else if (matchLowBitMask(SDValue(Node, 0))) {
3698     X = CurDAG->getAllOnesConstant(SDLoc(Node), NVT);
3699   } else if (!matchPatternD(Node))
3700     return false;
3701 
3702   // If we need to negate the shift amount, require BMI2 BZHI support.
3703   // It's just too unprofitable for BMI1 BEXTR.
3704   if (NegateNBits && !Subtarget->hasBMI2())
3705     return false;
3706 
3707   SDLoc DL(Node);
3708 
3709   // Truncate the shift amount.
3710   NBits = CurDAG->getNode(ISD::TRUNCATE, DL, MVT::i8, NBits);
3711   insertDAGNode(*CurDAG, SDValue(Node, 0), NBits);
3712 
3713   // Insert 8-bit NBits into lowest 8 bits of 32-bit register.
3714   // All the other bits are undefined, we do not care about them.
3715   SDValue ImplDef = SDValue(
3716       CurDAG->getMachineNode(TargetOpcode::IMPLICIT_DEF, DL, MVT::i32), 0);
3717   insertDAGNode(*CurDAG, SDValue(Node, 0), ImplDef);
3718 
3719   SDValue SRIdxVal = CurDAG->getTargetConstant(X86::sub_8bit, DL, MVT::i32);
3720   insertDAGNode(*CurDAG, SDValue(Node, 0), SRIdxVal);
3721   NBits = SDValue(CurDAG->getMachineNode(TargetOpcode::INSERT_SUBREG, DL,
3722                                          MVT::i32, ImplDef, NBits, SRIdxVal),
3723                   0);
3724   insertDAGNode(*CurDAG, SDValue(Node, 0), NBits);
3725 
3726   // We might have matched the amount of high bits to be cleared,
3727   // but we want the amount of low bits to be kept, so negate it then.
3728   if (NegateNBits) {
3729     SDValue BitWidthC = CurDAG->getConstant(NVT.getSizeInBits(), DL, MVT::i32);
3730     insertDAGNode(*CurDAG, SDValue(Node, 0), BitWidthC);
3731 
3732     NBits = CurDAG->getNode(ISD::SUB, DL, MVT::i32, BitWidthC, NBits);
3733     insertDAGNode(*CurDAG, SDValue(Node, 0), NBits);
3734   }
3735 
3736   if (Subtarget->hasBMI2()) {
3737     // Great, just emit the the BZHI..
3738     if (NVT != MVT::i32) {
3739       // But have to place the bit count into the wide-enough register first.
3740       NBits = CurDAG->getNode(ISD::ANY_EXTEND, DL, NVT, NBits);
3741       insertDAGNode(*CurDAG, SDValue(Node, 0), NBits);
3742     }
3743 
3744     SDValue Extract = CurDAG->getNode(X86ISD::BZHI, DL, NVT, X, NBits);
3745     ReplaceNode(Node, Extract.getNode());
3746     SelectCode(Extract.getNode());
3747     return true;
3748   }
3749 
3750   // Else, if we do *NOT* have BMI2, let's find out if the if the 'X' is
3751   // *logically* shifted (potentially with one-use trunc inbetween),
3752   // and the truncation was the only use of the shift,
3753   // and if so look past one-use truncation.
3754   {
3755     SDValue RealX = peekThroughOneUseTruncation(X);
3756     // FIXME: only if the shift is one-use?
3757     if (RealX != X && RealX.getOpcode() == ISD::SRL)
3758       X = RealX;
3759   }
3760 
3761   MVT XVT = X.getSimpleValueType();
3762 
3763   // Else, emitting BEXTR requires one more step.
3764   // The 'control' of BEXTR has the pattern of:
3765   // [15...8 bit][ 7...0 bit] location
3766   // [ bit count][     shift] name
3767   // I.e. 0b000000011'00000001 means  (x >> 0b1) & 0b11
3768 
3769   // Shift NBits left by 8 bits, thus producing 'control'.
3770   // This makes the low 8 bits to be zero.
3771   SDValue C8 = CurDAG->getConstant(8, DL, MVT::i8);
3772   insertDAGNode(*CurDAG, SDValue(Node, 0), C8);
3773   SDValue Control = CurDAG->getNode(ISD::SHL, DL, MVT::i32, NBits, C8);
3774   insertDAGNode(*CurDAG, SDValue(Node, 0), Control);
3775 
3776   // If the 'X' is *logically* shifted, we can fold that shift into 'control'.
3777   // FIXME: only if the shift is one-use?
3778   if (X.getOpcode() == ISD::SRL) {
3779     SDValue ShiftAmt = X.getOperand(1);
3780     X = X.getOperand(0);
3781 
3782     assert(ShiftAmt.getValueType() == MVT::i8 &&
3783            "Expected shift amount to be i8");
3784 
3785     // Now, *zero*-extend the shift amount. The bits 8...15 *must* be zero!
3786     // We could zext to i16 in some form, but we intentionally don't do that.
3787     SDValue OrigShiftAmt = ShiftAmt;
3788     ShiftAmt = CurDAG->getNode(ISD::ZERO_EXTEND, DL, MVT::i32, ShiftAmt);
3789     insertDAGNode(*CurDAG, OrigShiftAmt, ShiftAmt);
3790 
3791     // And now 'or' these low 8 bits of shift amount into the 'control'.
3792     Control = CurDAG->getNode(ISD::OR, DL, MVT::i32, Control, ShiftAmt);
3793     insertDAGNode(*CurDAG, SDValue(Node, 0), Control);
3794   }
3795 
3796   // But have to place the 'control' into the wide-enough register first.
3797   if (XVT != MVT::i32) {
3798     Control = CurDAG->getNode(ISD::ANY_EXTEND, DL, XVT, Control);
3799     insertDAGNode(*CurDAG, SDValue(Node, 0), Control);
3800   }
3801 
3802   // And finally, form the BEXTR itself.
3803   SDValue Extract = CurDAG->getNode(X86ISD::BEXTR, DL, XVT, X, Control);
3804 
3805   // The 'X' was originally truncated. Do that now.
3806   if (XVT != NVT) {
3807     insertDAGNode(*CurDAG, SDValue(Node, 0), Extract);
3808     Extract = CurDAG->getNode(ISD::TRUNCATE, DL, NVT, Extract);
3809   }
3810 
3811   ReplaceNode(Node, Extract.getNode());
3812   SelectCode(Extract.getNode());
3813 
3814   return true;
3815 }
3816 
3817 // See if this is an (X >> C1) & C2 that we can match to BEXTR/BEXTRI.
3818 MachineSDNode *X86DAGToDAGISel::matchBEXTRFromAndImm(SDNode *Node) {
3819   MVT NVT = Node->getSimpleValueType(0);
3820   SDLoc dl(Node);
3821 
3822   SDValue N0 = Node->getOperand(0);
3823   SDValue N1 = Node->getOperand(1);
3824 
3825   // If we have TBM we can use an immediate for the control. If we have BMI
3826   // we should only do this if the BEXTR instruction is implemented well.
3827   // Otherwise moving the control into a register makes this more costly.
3828   // TODO: Maybe load folding, greater than 32-bit masks, or a guarantee of LICM
3829   // hoisting the move immediate would make it worthwhile with a less optimal
3830   // BEXTR?
3831   bool PreferBEXTR =
3832       Subtarget->hasTBM() || (Subtarget->hasBMI() && Subtarget->hasFastBEXTR());
3833   if (!PreferBEXTR && !Subtarget->hasBMI2())
3834     return nullptr;
3835 
3836   // Must have a shift right.
3837   if (N0->getOpcode() != ISD::SRL && N0->getOpcode() != ISD::SRA)
3838     return nullptr;
3839 
3840   // Shift can't have additional users.
3841   if (!N0->hasOneUse())
3842     return nullptr;
3843 
3844   // Only supported for 32 and 64 bits.
3845   if (NVT != MVT::i32 && NVT != MVT::i64)
3846     return nullptr;
3847 
3848   // Shift amount and RHS of and must be constant.
3849   auto *MaskCst = dyn_cast<ConstantSDNode>(N1);
3850   auto *ShiftCst = dyn_cast<ConstantSDNode>(N0->getOperand(1));
3851   if (!MaskCst || !ShiftCst)
3852     return nullptr;
3853 
3854   // And RHS must be a mask.
3855   uint64_t Mask = MaskCst->getZExtValue();
3856   if (!isMask_64(Mask))
3857     return nullptr;
3858 
3859   uint64_t Shift = ShiftCst->getZExtValue();
3860   uint64_t MaskSize = llvm::popcount(Mask);
3861 
3862   // Don't interfere with something that can be handled by extracting AH.
3863   // TODO: If we are able to fold a load, BEXTR might still be better than AH.
3864   if (Shift == 8 && MaskSize == 8)
3865     return nullptr;
3866 
3867   // Make sure we are only using bits that were in the original value, not
3868   // shifted in.
3869   if (Shift + MaskSize > NVT.getSizeInBits())
3870     return nullptr;
3871 
3872   // BZHI, if available, is always fast, unlike BEXTR. But even if we decide
3873   // that we can't use BEXTR, it is only worthwhile using BZHI if the mask
3874   // does not fit into 32 bits. Load folding is not a sufficient reason.
3875   if (!PreferBEXTR && MaskSize <= 32)
3876     return nullptr;
3877 
3878   SDValue Control;
3879   unsigned ROpc, MOpc;
3880 
3881   if (!PreferBEXTR) {
3882     assert(Subtarget->hasBMI2() && "We must have BMI2's BZHI then.");
3883     // If we can't make use of BEXTR then we can't fuse shift+mask stages.
3884     // Let's perform the mask first, and apply shift later. Note that we need to
3885     // widen the mask to account for the fact that we'll apply shift afterwards!
3886     Control = CurDAG->getTargetConstant(Shift + MaskSize, dl, NVT);
3887     ROpc = NVT == MVT::i64 ? X86::BZHI64rr : X86::BZHI32rr;
3888     MOpc = NVT == MVT::i64 ? X86::BZHI64rm : X86::BZHI32rm;
3889     unsigned NewOpc = NVT == MVT::i64 ? X86::MOV32ri64 : X86::MOV32ri;
3890     Control = SDValue(CurDAG->getMachineNode(NewOpc, dl, NVT, Control), 0);
3891   } else {
3892     // The 'control' of BEXTR has the pattern of:
3893     // [15...8 bit][ 7...0 bit] location
3894     // [ bit count][     shift] name
3895     // I.e. 0b000000011'00000001 means  (x >> 0b1) & 0b11
3896     Control = CurDAG->getTargetConstant(Shift | (MaskSize << 8), dl, NVT);
3897     if (Subtarget->hasTBM()) {
3898       ROpc = NVT == MVT::i64 ? X86::BEXTRI64ri : X86::BEXTRI32ri;
3899       MOpc = NVT == MVT::i64 ? X86::BEXTRI64mi : X86::BEXTRI32mi;
3900     } else {
3901       assert(Subtarget->hasBMI() && "We must have BMI1's BEXTR then.");
3902       // BMI requires the immediate to placed in a register.
3903       ROpc = NVT == MVT::i64 ? X86::BEXTR64rr : X86::BEXTR32rr;
3904       MOpc = NVT == MVT::i64 ? X86::BEXTR64rm : X86::BEXTR32rm;
3905       unsigned NewOpc = NVT == MVT::i64 ? X86::MOV32ri64 : X86::MOV32ri;
3906       Control = SDValue(CurDAG->getMachineNode(NewOpc, dl, NVT, Control), 0);
3907     }
3908   }
3909 
3910   MachineSDNode *NewNode;
3911   SDValue Input = N0->getOperand(0);
3912   SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
3913   if (tryFoldLoad(Node, N0.getNode(), Input, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4)) {
3914     SDValue Ops[] = {
3915         Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, Control, Input.getOperand(0)};
3916     SDVTList VTs = CurDAG->getVTList(NVT, MVT::i32, MVT::Other);
3917     NewNode = CurDAG->getMachineNode(MOpc, dl, VTs, Ops);
3918     // Update the chain.
3919     ReplaceUses(Input.getValue(1), SDValue(NewNode, 2));
3920     // Record the mem-refs
3921     CurDAG->setNodeMemRefs(NewNode, {cast<LoadSDNode>(Input)->getMemOperand()});
3922   } else {
3923     NewNode = CurDAG->getMachineNode(ROpc, dl, NVT, MVT::i32, Input, Control);
3924   }
3925 
3926   if (!PreferBEXTR) {
3927     // We still need to apply the shift.
3928     SDValue ShAmt = CurDAG->getTargetConstant(Shift, dl, NVT);
3929     unsigned NewOpc = NVT == MVT::i64 ? X86::SHR64ri : X86::SHR32ri;
3930     NewNode =
3931         CurDAG->getMachineNode(NewOpc, dl, NVT, SDValue(NewNode, 0), ShAmt);
3932   }
3933 
3934   return NewNode;
3935 }
3936 
3937 // Emit a PCMISTR(I/M) instruction.
3938 MachineSDNode *X86DAGToDAGISel::emitPCMPISTR(unsigned ROpc, unsigned MOpc,
3939                                              bool MayFoldLoad, const SDLoc &dl,
3940                                              MVT VT, SDNode *Node) {
3941   SDValue N0 = Node->getOperand(0);
3942   SDValue N1 = Node->getOperand(1);
3943   SDValue Imm = Node->getOperand(2);
3944   auto *Val = cast<ConstantSDNode>(Imm)->getConstantIntValue();
3945   Imm = CurDAG->getTargetConstant(*Val, SDLoc(Node), Imm.getValueType());
3946 
3947   // Try to fold a load. No need to check alignment.
3948   SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
3949   if (MayFoldLoad && tryFoldLoad(Node, N1, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4)) {
3950     SDValue Ops[] = { N0, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, Imm,
3951                       N1.getOperand(0) };
3952     SDVTList VTs = CurDAG->getVTList(VT, MVT::i32, MVT::Other);
3953     MachineSDNode *CNode = CurDAG->getMachineNode(MOpc, dl, VTs, Ops);
3954     // Update the chain.
3955     ReplaceUses(N1.getValue(1), SDValue(CNode, 2));
3956     // Record the mem-refs
3957     CurDAG->setNodeMemRefs(CNode, {cast<LoadSDNode>(N1)->getMemOperand()});
3958     return CNode;
3959   }
3960 
3961   SDValue Ops[] = { N0, N1, Imm };
3962   SDVTList VTs = CurDAG->getVTList(VT, MVT::i32);
3963   MachineSDNode *CNode = CurDAG->getMachineNode(ROpc, dl, VTs, Ops);
3964   return CNode;
3965 }
3966 
3967 // Emit a PCMESTR(I/M) instruction. Also return the Glue result in case we need
3968 // to emit a second instruction after this one. This is needed since we have two
3969 // copyToReg nodes glued before this and we need to continue that glue through.
3970 MachineSDNode *X86DAGToDAGISel::emitPCMPESTR(unsigned ROpc, unsigned MOpc,
3971                                              bool MayFoldLoad, const SDLoc &dl,
3972                                              MVT VT, SDNode *Node,
3973                                              SDValue &InGlue) {
3974   SDValue N0 = Node->getOperand(0);
3975   SDValue N2 = Node->getOperand(2);
3976   SDValue Imm = Node->getOperand(4);
3977   auto *Val = cast<ConstantSDNode>(Imm)->getConstantIntValue();
3978   Imm = CurDAG->getTargetConstant(*Val, SDLoc(Node), Imm.getValueType());
3979 
3980   // Try to fold a load. No need to check alignment.
3981   SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
3982   if (MayFoldLoad && tryFoldLoad(Node, N2, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4)) {
3983     SDValue Ops[] = { N0, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, Imm,
3984                       N2.getOperand(0), InGlue };
3985     SDVTList VTs = CurDAG->getVTList(VT, MVT::i32, MVT::Other, MVT::Glue);
3986     MachineSDNode *CNode = CurDAG->getMachineNode(MOpc, dl, VTs, Ops);
3987     InGlue = SDValue(CNode, 3);
3988     // Update the chain.
3989     ReplaceUses(N2.getValue(1), SDValue(CNode, 2));
3990     // Record the mem-refs
3991     CurDAG->setNodeMemRefs(CNode, {cast<LoadSDNode>(N2)->getMemOperand()});
3992     return CNode;
3993   }
3994 
3995   SDValue Ops[] = { N0, N2, Imm, InGlue };
3996   SDVTList VTs = CurDAG->getVTList(VT, MVT::i32, MVT::Glue);
3997   MachineSDNode *CNode = CurDAG->getMachineNode(ROpc, dl, VTs, Ops);
3998   InGlue = SDValue(CNode, 2);
3999   return CNode;
4000 }
4001 
4002 bool X86DAGToDAGISel::tryShiftAmountMod(SDNode *N) {
4003   EVT VT = N->getValueType(0);
4004 
4005   // Only handle scalar shifts.
4006   if (VT.isVector())
4007     return false;
4008 
4009   // Narrower shifts only mask to 5 bits in hardware.
4010   unsigned Size = VT == MVT::i64 ? 64 : 32;
4011 
4012   SDValue OrigShiftAmt = N->getOperand(1);
4013   SDValue ShiftAmt = OrigShiftAmt;
4014   SDLoc DL(N);
4015 
4016   // Skip over a truncate of the shift amount.
4017   if (ShiftAmt->getOpcode() == ISD::TRUNCATE)
4018     ShiftAmt = ShiftAmt->getOperand(0);
4019 
4020   // This function is called after X86DAGToDAGISel::matchBitExtract(),
4021   // so we are not afraid that we might mess up BZHI/BEXTR pattern.
4022 
4023   SDValue NewShiftAmt;
4024   if (ShiftAmt->getOpcode() == ISD::ADD || ShiftAmt->getOpcode() == ISD::SUB ||
4025       ShiftAmt->getOpcode() == ISD::XOR) {
4026     SDValue Add0 = ShiftAmt->getOperand(0);
4027     SDValue Add1 = ShiftAmt->getOperand(1);
4028     auto *Add0C = dyn_cast<ConstantSDNode>(Add0);
4029     auto *Add1C = dyn_cast<ConstantSDNode>(Add1);
4030     // If we are shifting by X+/-/^N where N == 0 mod Size, then just shift by X
4031     // to avoid the ADD/SUB/XOR.
4032     if (Add1C && Add1C->getAPIntValue().urem(Size) == 0) {
4033       NewShiftAmt = Add0;
4034 
4035     } else if (ShiftAmt->getOpcode() != ISD::ADD && ShiftAmt.hasOneUse() &&
4036                ((Add0C && Add0C->getAPIntValue().urem(Size) == Size - 1) ||
4037                 (Add1C && Add1C->getAPIntValue().urem(Size) == Size - 1))) {
4038       // If we are doing a NOT on just the lower bits with (Size*N-1) -/^ X
4039       // we can replace it with a NOT. In the XOR case it may save some code
4040       // size, in the SUB case it also may save a move.
4041       assert(Add0C == nullptr || Add1C == nullptr);
4042 
4043       // We can only do N-X, not X-N
4044       if (ShiftAmt->getOpcode() == ISD::SUB && Add0C == nullptr)
4045         return false;
4046 
4047       EVT OpVT = ShiftAmt.getValueType();
4048 
4049       SDValue AllOnes = CurDAG->getAllOnesConstant(DL, OpVT);
4050       NewShiftAmt = CurDAG->getNode(ISD::XOR, DL, OpVT,
4051                                     Add0C == nullptr ? Add0 : Add1, AllOnes);
4052       insertDAGNode(*CurDAG, OrigShiftAmt, AllOnes);
4053       insertDAGNode(*CurDAG, OrigShiftAmt, NewShiftAmt);
4054       // If we are shifting by N-X where N == 0 mod Size, then just shift by
4055       // -X to generate a NEG instead of a SUB of a constant.
4056     } else if (ShiftAmt->getOpcode() == ISD::SUB && Add0C &&
4057                Add0C->getZExtValue() != 0) {
4058       EVT SubVT = ShiftAmt.getValueType();
4059       SDValue X;
4060       if (Add0C->getZExtValue() % Size == 0)
4061         X = Add1;
4062       else if (ShiftAmt.hasOneUse() && Size == 64 &&
4063                Add0C->getZExtValue() % 32 == 0) {
4064         // We have a 64-bit shift by (n*32-x), turn it into -(x+n*32).
4065         // This is mainly beneficial if we already compute (x+n*32).
4066         if (Add1.getOpcode() == ISD::TRUNCATE) {
4067           Add1 = Add1.getOperand(0);
4068           SubVT = Add1.getValueType();
4069         }
4070         if (Add0.getValueType() != SubVT) {
4071           Add0 = CurDAG->getZExtOrTrunc(Add0, DL, SubVT);
4072           insertDAGNode(*CurDAG, OrigShiftAmt, Add0);
4073         }
4074 
4075         X = CurDAG->getNode(ISD::ADD, DL, SubVT, Add1, Add0);
4076         insertDAGNode(*CurDAG, OrigShiftAmt, X);
4077       } else
4078         return false;
4079       // Insert a negate op.
4080       // TODO: This isn't guaranteed to replace the sub if there is a logic cone
4081       // that uses it that's not a shift.
4082       SDValue Zero = CurDAG->getConstant(0, DL, SubVT);
4083       SDValue Neg = CurDAG->getNode(ISD::SUB, DL, SubVT, Zero, X);
4084       NewShiftAmt = Neg;
4085 
4086       // Insert these operands into a valid topological order so they can
4087       // get selected independently.
4088       insertDAGNode(*CurDAG, OrigShiftAmt, Zero);
4089       insertDAGNode(*CurDAG, OrigShiftAmt, Neg);
4090     } else
4091       return false;
4092   } else
4093     return false;
4094 
4095   if (NewShiftAmt.getValueType() != MVT::i8) {
4096     // Need to truncate the shift amount.
4097     NewShiftAmt = CurDAG->getNode(ISD::TRUNCATE, DL, MVT::i8, NewShiftAmt);
4098     // Add to a correct topological ordering.
4099     insertDAGNode(*CurDAG, OrigShiftAmt, NewShiftAmt);
4100   }
4101 
4102   // Insert a new mask to keep the shift amount legal. This should be removed
4103   // by isel patterns.
4104   NewShiftAmt = CurDAG->getNode(ISD::AND, DL, MVT::i8, NewShiftAmt,
4105                                 CurDAG->getConstant(Size - 1, DL, MVT::i8));
4106   // Place in a correct topological ordering.
4107   insertDAGNode(*CurDAG, OrigShiftAmt, NewShiftAmt);
4108 
4109   SDNode *UpdatedNode = CurDAG->UpdateNodeOperands(N, N->getOperand(0),
4110                                                    NewShiftAmt);
4111   if (UpdatedNode != N) {
4112     // If we found an existing node, we should replace ourselves with that node
4113     // and wait for it to be selected after its other users.
4114     ReplaceNode(N, UpdatedNode);
4115     return true;
4116   }
4117 
4118   // If the original shift amount is now dead, delete it so that we don't run
4119   // it through isel.
4120   if (OrigShiftAmt.getNode()->use_empty())
4121     CurDAG->RemoveDeadNode(OrigShiftAmt.getNode());
4122 
4123   // Now that we've optimized the shift amount, defer to normal isel to get
4124   // load folding and legacy vs BMI2 selection without repeating it here.
4125   SelectCode(N);
4126   return true;
4127 }
4128 
4129 bool X86DAGToDAGISel::tryShrinkShlLogicImm(SDNode *N) {
4130   MVT NVT = N->getSimpleValueType(0);
4131   unsigned Opcode = N->getOpcode();
4132   SDLoc dl(N);
4133 
4134   // For operations of the form (x << C1) op C2, check if we can use a smaller
4135   // encoding for C2 by transforming it into (x op (C2>>C1)) << C1.
4136   SDValue Shift = N->getOperand(0);
4137   SDValue N1 = N->getOperand(1);
4138 
4139   auto *Cst = dyn_cast<ConstantSDNode>(N1);
4140   if (!Cst)
4141     return false;
4142 
4143   int64_t Val = Cst->getSExtValue();
4144 
4145   // If we have an any_extend feeding the AND, look through it to see if there
4146   // is a shift behind it. But only if the AND doesn't use the extended bits.
4147   // FIXME: Generalize this to other ANY_EXTEND than i32 to i64?
4148   bool FoundAnyExtend = false;
4149   if (Shift.getOpcode() == ISD::ANY_EXTEND && Shift.hasOneUse() &&
4150       Shift.getOperand(0).getSimpleValueType() == MVT::i32 &&
4151       isUInt<32>(Val)) {
4152     FoundAnyExtend = true;
4153     Shift = Shift.getOperand(0);
4154   }
4155 
4156   if (Shift.getOpcode() != ISD::SHL || !Shift.hasOneUse())
4157     return false;
4158 
4159   // i8 is unshrinkable, i16 should be promoted to i32.
4160   if (NVT != MVT::i32 && NVT != MVT::i64)
4161     return false;
4162 
4163   auto *ShlCst = dyn_cast<ConstantSDNode>(Shift.getOperand(1));
4164   if (!ShlCst)
4165     return false;
4166 
4167   uint64_t ShAmt = ShlCst->getZExtValue();
4168 
4169   // Make sure that we don't change the operation by removing bits.
4170   // This only matters for OR and XOR, AND is unaffected.
4171   uint64_t RemovedBitsMask = (1ULL << ShAmt) - 1;
4172   if (Opcode != ISD::AND && (Val & RemovedBitsMask) != 0)
4173     return false;
4174 
4175   // Check the minimum bitwidth for the new constant.
4176   // TODO: Using 16 and 8 bit operations is also possible for or32 & xor32.
4177   auto CanShrinkImmediate = [&](int64_t &ShiftedVal) {
4178     if (Opcode == ISD::AND) {
4179       // AND32ri is the same as AND64ri32 with zext imm.
4180       // Try this before sign extended immediates below.
4181       ShiftedVal = (uint64_t)Val >> ShAmt;
4182       if (NVT == MVT::i64 && !isUInt<32>(Val) && isUInt<32>(ShiftedVal))
4183         return true;
4184       // Also swap order when the AND can become MOVZX.
4185       if (ShiftedVal == UINT8_MAX || ShiftedVal == UINT16_MAX)
4186         return true;
4187     }
4188     ShiftedVal = Val >> ShAmt;
4189     if ((!isInt<8>(Val) && isInt<8>(ShiftedVal)) ||
4190         (!isInt<32>(Val) && isInt<32>(ShiftedVal)))
4191       return true;
4192     if (Opcode != ISD::AND) {
4193       // MOV32ri+OR64r/XOR64r is cheaper than MOV64ri64+OR64rr/XOR64rr
4194       ShiftedVal = (uint64_t)Val >> ShAmt;
4195       if (NVT == MVT::i64 && !isUInt<32>(Val) && isUInt<32>(ShiftedVal))
4196         return true;
4197     }
4198     return false;
4199   };
4200 
4201   int64_t ShiftedVal;
4202   if (!CanShrinkImmediate(ShiftedVal))
4203     return false;
4204 
4205   // Ok, we can reorder to get a smaller immediate.
4206 
4207   // But, its possible the original immediate allowed an AND to become MOVZX.
4208   // Doing this late due to avoid the MakedValueIsZero call as late as
4209   // possible.
4210   if (Opcode == ISD::AND) {
4211     // Find the smallest zext this could possibly be.
4212     unsigned ZExtWidth = Cst->getAPIntValue().getActiveBits();
4213     ZExtWidth = llvm::bit_ceil(std::max(ZExtWidth, 8U));
4214 
4215     // Figure out which bits need to be zero to achieve that mask.
4216     APInt NeededMask = APInt::getLowBitsSet(NVT.getSizeInBits(),
4217                                             ZExtWidth);
4218     NeededMask &= ~Cst->getAPIntValue();
4219 
4220     if (CurDAG->MaskedValueIsZero(N->getOperand(0), NeededMask))
4221       return false;
4222   }
4223 
4224   SDValue X = Shift.getOperand(0);
4225   if (FoundAnyExtend) {
4226     SDValue NewX = CurDAG->getNode(ISD::ANY_EXTEND, dl, NVT, X);
4227     insertDAGNode(*CurDAG, SDValue(N, 0), NewX);
4228     X = NewX;
4229   }
4230 
4231   SDValue NewCst = CurDAG->getConstant(ShiftedVal, dl, NVT);
4232   insertDAGNode(*CurDAG, SDValue(N, 0), NewCst);
4233   SDValue NewBinOp = CurDAG->getNode(Opcode, dl, NVT, X, NewCst);
4234   insertDAGNode(*CurDAG, SDValue(N, 0), NewBinOp);
4235   SDValue NewSHL = CurDAG->getNode(ISD::SHL, dl, NVT, NewBinOp,
4236                                    Shift.getOperand(1));
4237   ReplaceNode(N, NewSHL.getNode());
4238   SelectCode(NewSHL.getNode());
4239   return true;
4240 }
4241 
4242 bool X86DAGToDAGISel::matchVPTERNLOG(SDNode *Root, SDNode *ParentA,
4243                                      SDNode *ParentB, SDNode *ParentC,
4244                                      SDValue A, SDValue B, SDValue C,
4245                                      uint8_t Imm) {
4246   assert(A.isOperandOf(ParentA) && B.isOperandOf(ParentB) &&
4247          C.isOperandOf(ParentC) && "Incorrect parent node");
4248 
4249   auto tryFoldLoadOrBCast =
4250       [this](SDNode *Root, SDNode *P, SDValue &L, SDValue &Base, SDValue &Scale,
4251              SDValue &Index, SDValue &Disp, SDValue &Segment) {
4252         if (tryFoldLoad(Root, P, L, Base, Scale, Index, Disp, Segment))
4253           return true;
4254 
4255         // Not a load, check for broadcast which may be behind a bitcast.
4256         if (L.getOpcode() == ISD::BITCAST && L.hasOneUse()) {
4257           P = L.getNode();
4258           L = L.getOperand(0);
4259         }
4260 
4261         if (L.getOpcode() != X86ISD::VBROADCAST_LOAD)
4262           return false;
4263 
4264         // Only 32 and 64 bit broadcasts are supported.
4265         auto *MemIntr = cast<MemIntrinsicSDNode>(L);
4266         unsigned Size = MemIntr->getMemoryVT().getSizeInBits();
4267         if (Size != 32 && Size != 64)
4268           return false;
4269 
4270         return tryFoldBroadcast(Root, P, L, Base, Scale, Index, Disp, Segment);
4271       };
4272 
4273   bool FoldedLoad = false;
4274   SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
4275   if (tryFoldLoadOrBCast(Root, ParentC, C, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4)) {
4276     FoldedLoad = true;
4277   } else if (tryFoldLoadOrBCast(Root, ParentA, A, Tmp0, Tmp1, Tmp2, Tmp3,
4278                                 Tmp4)) {
4279     FoldedLoad = true;
4280     std::swap(A, C);
4281     // Swap bits 1/4 and 3/6.
4282     uint8_t OldImm = Imm;
4283     Imm = OldImm & 0xa5;
4284     if (OldImm & 0x02) Imm |= 0x10;
4285     if (OldImm & 0x10) Imm |= 0x02;
4286     if (OldImm & 0x08) Imm |= 0x40;
4287     if (OldImm & 0x40) Imm |= 0x08;
4288   } else if (tryFoldLoadOrBCast(Root, ParentB, B, Tmp0, Tmp1, Tmp2, Tmp3,
4289                                 Tmp4)) {
4290     FoldedLoad = true;
4291     std::swap(B, C);
4292     // Swap bits 1/2 and 5/6.
4293     uint8_t OldImm = Imm;
4294     Imm = OldImm & 0x99;
4295     if (OldImm & 0x02) Imm |= 0x04;
4296     if (OldImm & 0x04) Imm |= 0x02;
4297     if (OldImm & 0x20) Imm |= 0x40;
4298     if (OldImm & 0x40) Imm |= 0x20;
4299   }
4300 
4301   SDLoc DL(Root);
4302 
4303   SDValue TImm = CurDAG->getTargetConstant(Imm, DL, MVT::i8);
4304 
4305   MVT NVT = Root->getSimpleValueType(0);
4306 
4307   MachineSDNode *MNode;
4308   if (FoldedLoad) {
4309     SDVTList VTs = CurDAG->getVTList(NVT, MVT::Other);
4310 
4311     unsigned Opc;
4312     if (C.getOpcode() == X86ISD::VBROADCAST_LOAD) {
4313       auto *MemIntr = cast<MemIntrinsicSDNode>(C);
4314       unsigned EltSize = MemIntr->getMemoryVT().getSizeInBits();
4315       assert((EltSize == 32 || EltSize == 64) && "Unexpected broadcast size!");
4316 
4317       bool UseD = EltSize == 32;
4318       if (NVT.is128BitVector())
4319         Opc = UseD ? X86::VPTERNLOGDZ128rmbi : X86::VPTERNLOGQZ128rmbi;
4320       else if (NVT.is256BitVector())
4321         Opc = UseD ? X86::VPTERNLOGDZ256rmbi : X86::VPTERNLOGQZ256rmbi;
4322       else if (NVT.is512BitVector())
4323         Opc = UseD ? X86::VPTERNLOGDZrmbi : X86::VPTERNLOGQZrmbi;
4324       else
4325         llvm_unreachable("Unexpected vector size!");
4326     } else {
4327       bool UseD = NVT.getVectorElementType() == MVT::i32;
4328       if (NVT.is128BitVector())
4329         Opc = UseD ? X86::VPTERNLOGDZ128rmi : X86::VPTERNLOGQZ128rmi;
4330       else if (NVT.is256BitVector())
4331         Opc = UseD ? X86::VPTERNLOGDZ256rmi : X86::VPTERNLOGQZ256rmi;
4332       else if (NVT.is512BitVector())
4333         Opc = UseD ? X86::VPTERNLOGDZrmi : X86::VPTERNLOGQZrmi;
4334       else
4335         llvm_unreachable("Unexpected vector size!");
4336     }
4337 
4338     SDValue Ops[] = {A, B, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, TImm, C.getOperand(0)};
4339     MNode = CurDAG->getMachineNode(Opc, DL, VTs, Ops);
4340 
4341     // Update the chain.
4342     ReplaceUses(C.getValue(1), SDValue(MNode, 1));
4343     // Record the mem-refs
4344     CurDAG->setNodeMemRefs(MNode, {cast<MemSDNode>(C)->getMemOperand()});
4345   } else {
4346     bool UseD = NVT.getVectorElementType() == MVT::i32;
4347     unsigned Opc;
4348     if (NVT.is128BitVector())
4349       Opc = UseD ? X86::VPTERNLOGDZ128rri : X86::VPTERNLOGQZ128rri;
4350     else if (NVT.is256BitVector())
4351       Opc = UseD ? X86::VPTERNLOGDZ256rri : X86::VPTERNLOGQZ256rri;
4352     else if (NVT.is512BitVector())
4353       Opc = UseD ? X86::VPTERNLOGDZrri : X86::VPTERNLOGQZrri;
4354     else
4355       llvm_unreachable("Unexpected vector size!");
4356 
4357     MNode = CurDAG->getMachineNode(Opc, DL, NVT, {A, B, C, TImm});
4358   }
4359 
4360   ReplaceUses(SDValue(Root, 0), SDValue(MNode, 0));
4361   CurDAG->RemoveDeadNode(Root);
4362   return true;
4363 }
4364 
4365 // Try to match two logic ops to a VPTERNLOG.
4366 // FIXME: Handle more complex patterns that use an operand more than once?
4367 bool X86DAGToDAGISel::tryVPTERNLOG(SDNode *N) {
4368   MVT NVT = N->getSimpleValueType(0);
4369 
4370   // Make sure we support VPTERNLOG.
4371   if (!NVT.isVector() || !Subtarget->hasAVX512() ||
4372       NVT.getVectorElementType() == MVT::i1)
4373     return false;
4374 
4375   // We need VLX for 128/256-bit.
4376   if (!(Subtarget->hasVLX() || NVT.is512BitVector()))
4377     return false;
4378 
4379   SDValue N0 = N->getOperand(0);
4380   SDValue N1 = N->getOperand(1);
4381 
4382   auto getFoldableLogicOp = [](SDValue Op) {
4383     // Peek through single use bitcast.
4384     if (Op.getOpcode() == ISD::BITCAST && Op.hasOneUse())
4385       Op = Op.getOperand(0);
4386 
4387     if (!Op.hasOneUse())
4388       return SDValue();
4389 
4390     unsigned Opc = Op.getOpcode();
4391     if (Opc == ISD::AND || Opc == ISD::OR || Opc == ISD::XOR ||
4392         Opc == X86ISD::ANDNP)
4393       return Op;
4394 
4395     return SDValue();
4396   };
4397 
4398   SDValue A, FoldableOp;
4399   if ((FoldableOp = getFoldableLogicOp(N1))) {
4400     A = N0;
4401   } else if ((FoldableOp = getFoldableLogicOp(N0))) {
4402     A = N1;
4403   } else
4404     return false;
4405 
4406   SDValue B = FoldableOp.getOperand(0);
4407   SDValue C = FoldableOp.getOperand(1);
4408   SDNode *ParentA = N;
4409   SDNode *ParentB = FoldableOp.getNode();
4410   SDNode *ParentC = FoldableOp.getNode();
4411 
4412   // We can build the appropriate control immediate by performing the logic
4413   // operation we're matching using these constants for A, B, and C.
4414   uint8_t TernlogMagicA = 0xf0;
4415   uint8_t TernlogMagicB = 0xcc;
4416   uint8_t TernlogMagicC = 0xaa;
4417 
4418   // Some of the inputs may be inverted, peek through them and invert the
4419   // magic values accordingly.
4420   // TODO: There may be a bitcast before the xor that we should peek through.
4421   auto PeekThroughNot = [](SDValue &Op, SDNode *&Parent, uint8_t &Magic) {
4422     if (Op.getOpcode() == ISD::XOR && Op.hasOneUse() &&
4423         ISD::isBuildVectorAllOnes(Op.getOperand(1).getNode())) {
4424       Magic = ~Magic;
4425       Parent = Op.getNode();
4426       Op = Op.getOperand(0);
4427     }
4428   };
4429 
4430   PeekThroughNot(A, ParentA, TernlogMagicA);
4431   PeekThroughNot(B, ParentB, TernlogMagicB);
4432   PeekThroughNot(C, ParentC, TernlogMagicC);
4433 
4434   uint8_t Imm;
4435   switch (FoldableOp.getOpcode()) {
4436   default: llvm_unreachable("Unexpected opcode!");
4437   case ISD::AND:      Imm = TernlogMagicB & TernlogMagicC; break;
4438   case ISD::OR:       Imm = TernlogMagicB | TernlogMagicC; break;
4439   case ISD::XOR:      Imm = TernlogMagicB ^ TernlogMagicC; break;
4440   case X86ISD::ANDNP: Imm = ~(TernlogMagicB) & TernlogMagicC; break;
4441   }
4442 
4443   switch (N->getOpcode()) {
4444   default: llvm_unreachable("Unexpected opcode!");
4445   case X86ISD::ANDNP:
4446     if (A == N0)
4447       Imm &= ~TernlogMagicA;
4448     else
4449       Imm = ~(Imm) & TernlogMagicA;
4450     break;
4451   case ISD::AND: Imm &= TernlogMagicA; break;
4452   case ISD::OR:  Imm |= TernlogMagicA; break;
4453   case ISD::XOR: Imm ^= TernlogMagicA; break;
4454   }
4455 
4456   return matchVPTERNLOG(N, ParentA, ParentB, ParentC, A, B, C, Imm);
4457 }
4458 
4459 /// If the high bits of an 'and' operand are known zero, try setting the
4460 /// high bits of an 'and' constant operand to produce a smaller encoding by
4461 /// creating a small, sign-extended negative immediate rather than a large
4462 /// positive one. This reverses a transform in SimplifyDemandedBits that
4463 /// shrinks mask constants by clearing bits. There is also a possibility that
4464 /// the 'and' mask can be made -1, so the 'and' itself is unnecessary. In that
4465 /// case, just replace the 'and'. Return 'true' if the node is replaced.
4466 bool X86DAGToDAGISel::shrinkAndImmediate(SDNode *And) {
4467   // i8 is unshrinkable, i16 should be promoted to i32, and vector ops don't
4468   // have immediate operands.
4469   MVT VT = And->getSimpleValueType(0);
4470   if (VT != MVT::i32 && VT != MVT::i64)
4471     return false;
4472 
4473   auto *And1C = dyn_cast<ConstantSDNode>(And->getOperand(1));
4474   if (!And1C)
4475     return false;
4476 
4477   // Bail out if the mask constant is already negative. It's can't shrink more.
4478   // If the upper 32 bits of a 64 bit mask are all zeros, we have special isel
4479   // patterns to use a 32-bit and instead of a 64-bit and by relying on the
4480   // implicit zeroing of 32 bit ops. So we should check if the lower 32 bits
4481   // are negative too.
4482   APInt MaskVal = And1C->getAPIntValue();
4483   unsigned MaskLZ = MaskVal.countl_zero();
4484   if (!MaskLZ || (VT == MVT::i64 && MaskLZ == 32))
4485     return false;
4486 
4487   // Don't extend into the upper 32 bits of a 64 bit mask.
4488   if (VT == MVT::i64 && MaskLZ >= 32) {
4489     MaskLZ -= 32;
4490     MaskVal = MaskVal.trunc(32);
4491   }
4492 
4493   SDValue And0 = And->getOperand(0);
4494   APInt HighZeros = APInt::getHighBitsSet(MaskVal.getBitWidth(), MaskLZ);
4495   APInt NegMaskVal = MaskVal | HighZeros;
4496 
4497   // If a negative constant would not allow a smaller encoding, there's no need
4498   // to continue. Only change the constant when we know it's a win.
4499   unsigned MinWidth = NegMaskVal.getSignificantBits();
4500   if (MinWidth > 32 || (MinWidth > 8 && MaskVal.getSignificantBits() <= 32))
4501     return false;
4502 
4503   // Extend masks if we truncated above.
4504   if (VT == MVT::i64 && MaskVal.getBitWidth() < 64) {
4505     NegMaskVal = NegMaskVal.zext(64);
4506     HighZeros = HighZeros.zext(64);
4507   }
4508 
4509   // The variable operand must be all zeros in the top bits to allow using the
4510   // new, negative constant as the mask.
4511   if (!CurDAG->MaskedValueIsZero(And0, HighZeros))
4512     return false;
4513 
4514   // Check if the mask is -1. In that case, this is an unnecessary instruction
4515   // that escaped earlier analysis.
4516   if (NegMaskVal.isAllOnes()) {
4517     ReplaceNode(And, And0.getNode());
4518     return true;
4519   }
4520 
4521   // A negative mask allows a smaller encoding. Create a new 'and' node.
4522   SDValue NewMask = CurDAG->getConstant(NegMaskVal, SDLoc(And), VT);
4523   insertDAGNode(*CurDAG, SDValue(And, 0), NewMask);
4524   SDValue NewAnd = CurDAG->getNode(ISD::AND, SDLoc(And), VT, And0, NewMask);
4525   ReplaceNode(And, NewAnd.getNode());
4526   SelectCode(NewAnd.getNode());
4527   return true;
4528 }
4529 
4530 static unsigned getVPTESTMOpc(MVT TestVT, bool IsTestN, bool FoldedLoad,
4531                               bool FoldedBCast, bool Masked) {
4532 #define VPTESTM_CASE(VT, SUFFIX) \
4533 case MVT::VT: \
4534   if (Masked) \
4535     return IsTestN ? X86::VPTESTNM##SUFFIX##k: X86::VPTESTM##SUFFIX##k; \
4536   return IsTestN ? X86::VPTESTNM##SUFFIX : X86::VPTESTM##SUFFIX;
4537 
4538 
4539 #define VPTESTM_BROADCAST_CASES(SUFFIX) \
4540 default: llvm_unreachable("Unexpected VT!"); \
4541 VPTESTM_CASE(v4i32, DZ128##SUFFIX) \
4542 VPTESTM_CASE(v2i64, QZ128##SUFFIX) \
4543 VPTESTM_CASE(v8i32, DZ256##SUFFIX) \
4544 VPTESTM_CASE(v4i64, QZ256##SUFFIX) \
4545 VPTESTM_CASE(v16i32, DZ##SUFFIX) \
4546 VPTESTM_CASE(v8i64, QZ##SUFFIX)
4547 
4548 #define VPTESTM_FULL_CASES(SUFFIX) \
4549 VPTESTM_BROADCAST_CASES(SUFFIX) \
4550 VPTESTM_CASE(v16i8, BZ128##SUFFIX) \
4551 VPTESTM_CASE(v8i16, WZ128##SUFFIX) \
4552 VPTESTM_CASE(v32i8, BZ256##SUFFIX) \
4553 VPTESTM_CASE(v16i16, WZ256##SUFFIX) \
4554 VPTESTM_CASE(v64i8, BZ##SUFFIX) \
4555 VPTESTM_CASE(v32i16, WZ##SUFFIX)
4556 
4557   if (FoldedBCast) {
4558     switch (TestVT.SimpleTy) {
4559     VPTESTM_BROADCAST_CASES(rmb)
4560     }
4561   }
4562 
4563   if (FoldedLoad) {
4564     switch (TestVT.SimpleTy) {
4565     VPTESTM_FULL_CASES(rm)
4566     }
4567   }
4568 
4569   switch (TestVT.SimpleTy) {
4570   VPTESTM_FULL_CASES(rr)
4571   }
4572 
4573 #undef VPTESTM_FULL_CASES
4574 #undef VPTESTM_BROADCAST_CASES
4575 #undef VPTESTM_CASE
4576 }
4577 
4578 // Try to create VPTESTM instruction. If InMask is not null, it will be used
4579 // to form a masked operation.
4580 bool X86DAGToDAGISel::tryVPTESTM(SDNode *Root, SDValue Setcc,
4581                                  SDValue InMask) {
4582   assert(Subtarget->hasAVX512() && "Expected AVX512!");
4583   assert(Setcc.getSimpleValueType().getVectorElementType() == MVT::i1 &&
4584          "Unexpected VT!");
4585 
4586   // Look for equal and not equal compares.
4587   ISD::CondCode CC = cast<CondCodeSDNode>(Setcc.getOperand(2))->get();
4588   if (CC != ISD::SETEQ && CC != ISD::SETNE)
4589     return false;
4590 
4591   SDValue SetccOp0 = Setcc.getOperand(0);
4592   SDValue SetccOp1 = Setcc.getOperand(1);
4593 
4594   // Canonicalize the all zero vector to the RHS.
4595   if (ISD::isBuildVectorAllZeros(SetccOp0.getNode()))
4596     std::swap(SetccOp0, SetccOp1);
4597 
4598   // See if we're comparing against zero.
4599   if (!ISD::isBuildVectorAllZeros(SetccOp1.getNode()))
4600     return false;
4601 
4602   SDValue N0 = SetccOp0;
4603 
4604   MVT CmpVT = N0.getSimpleValueType();
4605   MVT CmpSVT = CmpVT.getVectorElementType();
4606 
4607   // Start with both operands the same. We'll try to refine this.
4608   SDValue Src0 = N0;
4609   SDValue Src1 = N0;
4610 
4611   {
4612     // Look through single use bitcasts.
4613     SDValue N0Temp = N0;
4614     if (N0Temp.getOpcode() == ISD::BITCAST && N0Temp.hasOneUse())
4615       N0Temp = N0.getOperand(0);
4616 
4617      // Look for single use AND.
4618     if (N0Temp.getOpcode() == ISD::AND && N0Temp.hasOneUse()) {
4619       Src0 = N0Temp.getOperand(0);
4620       Src1 = N0Temp.getOperand(1);
4621     }
4622   }
4623 
4624   // Without VLX we need to widen the operation.
4625   bool Widen = !Subtarget->hasVLX() && !CmpVT.is512BitVector();
4626 
4627   auto tryFoldLoadOrBCast = [&](SDNode *Root, SDNode *P, SDValue &L,
4628                                 SDValue &Base, SDValue &Scale, SDValue &Index,
4629                                 SDValue &Disp, SDValue &Segment) {
4630     // If we need to widen, we can't fold the load.
4631     if (!Widen)
4632       if (tryFoldLoad(Root, P, L, Base, Scale, Index, Disp, Segment))
4633         return true;
4634 
4635     // If we didn't fold a load, try to match broadcast. No widening limitation
4636     // for this. But only 32 and 64 bit types are supported.
4637     if (CmpSVT != MVT::i32 && CmpSVT != MVT::i64)
4638       return false;
4639 
4640     // Look through single use bitcasts.
4641     if (L.getOpcode() == ISD::BITCAST && L.hasOneUse()) {
4642       P = L.getNode();
4643       L = L.getOperand(0);
4644     }
4645 
4646     if (L.getOpcode() != X86ISD::VBROADCAST_LOAD)
4647       return false;
4648 
4649     auto *MemIntr = cast<MemIntrinsicSDNode>(L);
4650     if (MemIntr->getMemoryVT().getSizeInBits() != CmpSVT.getSizeInBits())
4651       return false;
4652 
4653     return tryFoldBroadcast(Root, P, L, Base, Scale, Index, Disp, Segment);
4654   };
4655 
4656   // We can only fold loads if the sources are unique.
4657   bool CanFoldLoads = Src0 != Src1;
4658 
4659   bool FoldedLoad = false;
4660   SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
4661   if (CanFoldLoads) {
4662     FoldedLoad = tryFoldLoadOrBCast(Root, N0.getNode(), Src1, Tmp0, Tmp1, Tmp2,
4663                                     Tmp3, Tmp4);
4664     if (!FoldedLoad) {
4665       // And is commutative.
4666       FoldedLoad = tryFoldLoadOrBCast(Root, N0.getNode(), Src0, Tmp0, Tmp1,
4667                                       Tmp2, Tmp3, Tmp4);
4668       if (FoldedLoad)
4669         std::swap(Src0, Src1);
4670     }
4671   }
4672 
4673   bool FoldedBCast = FoldedLoad && Src1.getOpcode() == X86ISD::VBROADCAST_LOAD;
4674 
4675   bool IsMasked = InMask.getNode() != nullptr;
4676 
4677   SDLoc dl(Root);
4678 
4679   MVT ResVT = Setcc.getSimpleValueType();
4680   MVT MaskVT = ResVT;
4681   if (Widen) {
4682     // Widen the inputs using insert_subreg or copy_to_regclass.
4683     unsigned Scale = CmpVT.is128BitVector() ? 4 : 2;
4684     unsigned SubReg = CmpVT.is128BitVector() ? X86::sub_xmm : X86::sub_ymm;
4685     unsigned NumElts = CmpVT.getVectorNumElements() * Scale;
4686     CmpVT = MVT::getVectorVT(CmpSVT, NumElts);
4687     MaskVT = MVT::getVectorVT(MVT::i1, NumElts);
4688     SDValue ImplDef = SDValue(CurDAG->getMachineNode(X86::IMPLICIT_DEF, dl,
4689                                                      CmpVT), 0);
4690     Src0 = CurDAG->getTargetInsertSubreg(SubReg, dl, CmpVT, ImplDef, Src0);
4691 
4692     if (!FoldedBCast)
4693       Src1 = CurDAG->getTargetInsertSubreg(SubReg, dl, CmpVT, ImplDef, Src1);
4694 
4695     if (IsMasked) {
4696       // Widen the mask.
4697       unsigned RegClass = TLI->getRegClassFor(MaskVT)->getID();
4698       SDValue RC = CurDAG->getTargetConstant(RegClass, dl, MVT::i32);
4699       InMask = SDValue(CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS,
4700                                               dl, MaskVT, InMask, RC), 0);
4701     }
4702   }
4703 
4704   bool IsTestN = CC == ISD::SETEQ;
4705   unsigned Opc = getVPTESTMOpc(CmpVT, IsTestN, FoldedLoad, FoldedBCast,
4706                                IsMasked);
4707 
4708   MachineSDNode *CNode;
4709   if (FoldedLoad) {
4710     SDVTList VTs = CurDAG->getVTList(MaskVT, MVT::Other);
4711 
4712     if (IsMasked) {
4713       SDValue Ops[] = { InMask, Src0, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4,
4714                         Src1.getOperand(0) };
4715       CNode = CurDAG->getMachineNode(Opc, dl, VTs, Ops);
4716     } else {
4717       SDValue Ops[] = { Src0, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4,
4718                         Src1.getOperand(0) };
4719       CNode = CurDAG->getMachineNode(Opc, dl, VTs, Ops);
4720     }
4721 
4722     // Update the chain.
4723     ReplaceUses(Src1.getValue(1), SDValue(CNode, 1));
4724     // Record the mem-refs
4725     CurDAG->setNodeMemRefs(CNode, {cast<MemSDNode>(Src1)->getMemOperand()});
4726   } else {
4727     if (IsMasked)
4728       CNode = CurDAG->getMachineNode(Opc, dl, MaskVT, InMask, Src0, Src1);
4729     else
4730       CNode = CurDAG->getMachineNode(Opc, dl, MaskVT, Src0, Src1);
4731   }
4732 
4733   // If we widened, we need to shrink the mask VT.
4734   if (Widen) {
4735     unsigned RegClass = TLI->getRegClassFor(ResVT)->getID();
4736     SDValue RC = CurDAG->getTargetConstant(RegClass, dl, MVT::i32);
4737     CNode = CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS,
4738                                    dl, ResVT, SDValue(CNode, 0), RC);
4739   }
4740 
4741   ReplaceUses(SDValue(Root, 0), SDValue(CNode, 0));
4742   CurDAG->RemoveDeadNode(Root);
4743   return true;
4744 }
4745 
4746 // Try to match the bitselect pattern (or (and A, B), (andn A, C)). Turn it
4747 // into vpternlog.
4748 bool X86DAGToDAGISel::tryMatchBitSelect(SDNode *N) {
4749   assert(N->getOpcode() == ISD::OR && "Unexpected opcode!");
4750 
4751   MVT NVT = N->getSimpleValueType(0);
4752 
4753   // Make sure we support VPTERNLOG.
4754   if (!NVT.isVector() || !Subtarget->hasAVX512())
4755     return false;
4756 
4757   // We need VLX for 128/256-bit.
4758   if (!(Subtarget->hasVLX() || NVT.is512BitVector()))
4759     return false;
4760 
4761   SDValue N0 = N->getOperand(0);
4762   SDValue N1 = N->getOperand(1);
4763 
4764   // Canonicalize AND to LHS.
4765   if (N1.getOpcode() == ISD::AND)
4766     std::swap(N0, N1);
4767 
4768   if (N0.getOpcode() != ISD::AND ||
4769       N1.getOpcode() != X86ISD::ANDNP ||
4770       !N0.hasOneUse() || !N1.hasOneUse())
4771     return false;
4772 
4773   // ANDN is not commutable, use it to pick down A and C.
4774   SDValue A = N1.getOperand(0);
4775   SDValue C = N1.getOperand(1);
4776 
4777   // AND is commutable, if one operand matches A, the other operand is B.
4778   // Otherwise this isn't a match.
4779   SDValue B;
4780   if (N0.getOperand(0) == A)
4781     B = N0.getOperand(1);
4782   else if (N0.getOperand(1) == A)
4783     B = N0.getOperand(0);
4784   else
4785     return false;
4786 
4787   SDLoc dl(N);
4788   SDValue Imm = CurDAG->getTargetConstant(0xCA, dl, MVT::i8);
4789   SDValue Ternlog = CurDAG->getNode(X86ISD::VPTERNLOG, dl, NVT, A, B, C, Imm);
4790   ReplaceNode(N, Ternlog.getNode());
4791 
4792   return matchVPTERNLOG(Ternlog.getNode(), Ternlog.getNode(), Ternlog.getNode(),
4793                         Ternlog.getNode(), A, B, C, 0xCA);
4794 }
4795 
4796 void X86DAGToDAGISel::Select(SDNode *Node) {
4797   MVT NVT = Node->getSimpleValueType(0);
4798   unsigned Opcode = Node->getOpcode();
4799   SDLoc dl(Node);
4800 
4801   if (Node->isMachineOpcode()) {
4802     LLVM_DEBUG(dbgs() << "== "; Node->dump(CurDAG); dbgs() << '\n');
4803     Node->setNodeId(-1);
4804     return;   // Already selected.
4805   }
4806 
4807   switch (Opcode) {
4808   default: break;
4809   case ISD::INTRINSIC_W_CHAIN: {
4810     unsigned IntNo = Node->getConstantOperandVal(1);
4811     switch (IntNo) {
4812     default: break;
4813     case Intrinsic::x86_encodekey128:
4814     case Intrinsic::x86_encodekey256: {
4815       if (!Subtarget->hasKL())
4816         break;
4817 
4818       unsigned Opcode;
4819       switch (IntNo) {
4820       default: llvm_unreachable("Impossible intrinsic");
4821       case Intrinsic::x86_encodekey128: Opcode = X86::ENCODEKEY128; break;
4822       case Intrinsic::x86_encodekey256: Opcode = X86::ENCODEKEY256; break;
4823       }
4824 
4825       SDValue Chain = Node->getOperand(0);
4826       Chain = CurDAG->getCopyToReg(Chain, dl, X86::XMM0, Node->getOperand(3),
4827                                    SDValue());
4828       if (Opcode == X86::ENCODEKEY256)
4829         Chain = CurDAG->getCopyToReg(Chain, dl, X86::XMM1, Node->getOperand(4),
4830                                      Chain.getValue(1));
4831 
4832       MachineSDNode *Res = CurDAG->getMachineNode(
4833           Opcode, dl, Node->getVTList(),
4834           {Node->getOperand(2), Chain, Chain.getValue(1)});
4835       ReplaceNode(Node, Res);
4836       return;
4837     }
4838     case Intrinsic::x86_tileloadd64_internal:
4839     case Intrinsic::x86_tileloaddt164_internal: {
4840       if (!Subtarget->hasAMXTILE())
4841         break;
4842       unsigned Opc = IntNo == Intrinsic::x86_tileloadd64_internal
4843                          ? X86::PTILELOADDV
4844                          : X86::PTILELOADDT1V;
4845       // _tile_loadd_internal(row, col, buf, STRIDE)
4846       SDValue Base = Node->getOperand(4);
4847       SDValue Scale = getI8Imm(1, dl);
4848       SDValue Index = Node->getOperand(5);
4849       SDValue Disp = CurDAG->getTargetConstant(0, dl, MVT::i32);
4850       SDValue Segment = CurDAG->getRegister(0, MVT::i16);
4851       SDValue Chain = Node->getOperand(0);
4852       MachineSDNode *CNode;
4853       SDValue Ops[] = {Node->getOperand(2),
4854                        Node->getOperand(3),
4855                        Base,
4856                        Scale,
4857                        Index,
4858                        Disp,
4859                        Segment,
4860                        Chain};
4861       CNode = CurDAG->getMachineNode(Opc, dl, {MVT::x86amx, MVT::Other}, Ops);
4862       ReplaceNode(Node, CNode);
4863       return;
4864     }
4865     }
4866     break;
4867   }
4868   case ISD::INTRINSIC_VOID: {
4869     unsigned IntNo = Node->getConstantOperandVal(1);
4870     switch (IntNo) {
4871     default: break;
4872     case Intrinsic::x86_sse3_monitor:
4873     case Intrinsic::x86_monitorx:
4874     case Intrinsic::x86_clzero: {
4875       bool Use64BitPtr = Node->getOperand(2).getValueType() == MVT::i64;
4876 
4877       unsigned Opc = 0;
4878       switch (IntNo) {
4879       default: llvm_unreachable("Unexpected intrinsic!");
4880       case Intrinsic::x86_sse3_monitor:
4881         if (!Subtarget->hasSSE3())
4882           break;
4883         Opc = Use64BitPtr ? X86::MONITOR64rrr : X86::MONITOR32rrr;
4884         break;
4885       case Intrinsic::x86_monitorx:
4886         if (!Subtarget->hasMWAITX())
4887           break;
4888         Opc = Use64BitPtr ? X86::MONITORX64rrr : X86::MONITORX32rrr;
4889         break;
4890       case Intrinsic::x86_clzero:
4891         if (!Subtarget->hasCLZERO())
4892           break;
4893         Opc = Use64BitPtr ? X86::CLZERO64r : X86::CLZERO32r;
4894         break;
4895       }
4896 
4897       if (Opc) {
4898         unsigned PtrReg = Use64BitPtr ? X86::RAX : X86::EAX;
4899         SDValue Chain = CurDAG->getCopyToReg(Node->getOperand(0), dl, PtrReg,
4900                                              Node->getOperand(2), SDValue());
4901         SDValue InGlue = Chain.getValue(1);
4902 
4903         if (IntNo == Intrinsic::x86_sse3_monitor ||
4904             IntNo == Intrinsic::x86_monitorx) {
4905           // Copy the other two operands to ECX and EDX.
4906           Chain = CurDAG->getCopyToReg(Chain, dl, X86::ECX, Node->getOperand(3),
4907                                        InGlue);
4908           InGlue = Chain.getValue(1);
4909           Chain = CurDAG->getCopyToReg(Chain, dl, X86::EDX, Node->getOperand(4),
4910                                        InGlue);
4911           InGlue = Chain.getValue(1);
4912         }
4913 
4914         MachineSDNode *CNode = CurDAG->getMachineNode(Opc, dl, MVT::Other,
4915                                                       { Chain, InGlue});
4916         ReplaceNode(Node, CNode);
4917         return;
4918       }
4919 
4920       break;
4921     }
4922     case Intrinsic::x86_tilestored64_internal: {
4923       unsigned Opc = X86::PTILESTOREDV;
4924       // _tile_stored_internal(row, col, buf, STRIDE, c)
4925       SDValue Base = Node->getOperand(4);
4926       SDValue Scale = getI8Imm(1, dl);
4927       SDValue Index = Node->getOperand(5);
4928       SDValue Disp = CurDAG->getTargetConstant(0, dl, MVT::i32);
4929       SDValue Segment = CurDAG->getRegister(0, MVT::i16);
4930       SDValue Chain = Node->getOperand(0);
4931       MachineSDNode *CNode;
4932       SDValue Ops[] = {Node->getOperand(2),
4933                        Node->getOperand(3),
4934                        Base,
4935                        Scale,
4936                        Index,
4937                        Disp,
4938                        Segment,
4939                        Node->getOperand(6),
4940                        Chain};
4941       CNode = CurDAG->getMachineNode(Opc, dl, MVT::Other, Ops);
4942       ReplaceNode(Node, CNode);
4943       return;
4944     }
4945     case Intrinsic::x86_tileloadd64:
4946     case Intrinsic::x86_tileloaddt164:
4947     case Intrinsic::x86_tilestored64: {
4948       if (!Subtarget->hasAMXTILE())
4949         break;
4950       unsigned Opc;
4951       switch (IntNo) {
4952       default: llvm_unreachable("Unexpected intrinsic!");
4953       case Intrinsic::x86_tileloadd64:   Opc = X86::PTILELOADD; break;
4954       case Intrinsic::x86_tileloaddt164: Opc = X86::PTILELOADDT1; break;
4955       case Intrinsic::x86_tilestored64:  Opc = X86::PTILESTORED; break;
4956       }
4957       // FIXME: Match displacement and scale.
4958       unsigned TIndex = Node->getConstantOperandVal(2);
4959       SDValue TReg = getI8Imm(TIndex, dl);
4960       SDValue Base = Node->getOperand(3);
4961       SDValue Scale = getI8Imm(1, dl);
4962       SDValue Index = Node->getOperand(4);
4963       SDValue Disp = CurDAG->getTargetConstant(0, dl, MVT::i32);
4964       SDValue Segment = CurDAG->getRegister(0, MVT::i16);
4965       SDValue Chain = Node->getOperand(0);
4966       MachineSDNode *CNode;
4967       if (Opc == X86::PTILESTORED) {
4968         SDValue Ops[] = { Base, Scale, Index, Disp, Segment, TReg, Chain };
4969         CNode = CurDAG->getMachineNode(Opc, dl, MVT::Other, Ops);
4970       } else {
4971         SDValue Ops[] = { TReg, Base, Scale, Index, Disp, Segment, Chain };
4972         CNode = CurDAG->getMachineNode(Opc, dl, MVT::Other, Ops);
4973       }
4974       ReplaceNode(Node, CNode);
4975       return;
4976     }
4977     }
4978     break;
4979   }
4980   case ISD::BRIND:
4981   case X86ISD::NT_BRIND: {
4982     if (Subtarget->isTargetNaCl())
4983       // NaCl has its own pass where jmp %r32 are converted to jmp %r64. We
4984       // leave the instruction alone.
4985       break;
4986     if (Subtarget->isTarget64BitILP32()) {
4987       // Converts a 32-bit register to a 64-bit, zero-extended version of
4988       // it. This is needed because x86-64 can do many things, but jmp %r32
4989       // ain't one of them.
4990       SDValue Target = Node->getOperand(1);
4991       assert(Target.getValueType() == MVT::i32 && "Unexpected VT!");
4992       SDValue ZextTarget = CurDAG->getZExtOrTrunc(Target, dl, MVT::i64);
4993       SDValue Brind = CurDAG->getNode(Opcode, dl, MVT::Other,
4994                                       Node->getOperand(0), ZextTarget);
4995       ReplaceNode(Node, Brind.getNode());
4996       SelectCode(ZextTarget.getNode());
4997       SelectCode(Brind.getNode());
4998       return;
4999     }
5000     break;
5001   }
5002   case X86ISD::GlobalBaseReg:
5003     ReplaceNode(Node, getGlobalBaseReg());
5004     return;
5005 
5006   case ISD::BITCAST:
5007     // Just drop all 128/256/512-bit bitcasts.
5008     if (NVT.is512BitVector() || NVT.is256BitVector() || NVT.is128BitVector() ||
5009         NVT == MVT::f128) {
5010       ReplaceUses(SDValue(Node, 0), Node->getOperand(0));
5011       CurDAG->RemoveDeadNode(Node);
5012       return;
5013     }
5014     break;
5015 
5016   case ISD::SRL:
5017     if (matchBitExtract(Node))
5018       return;
5019     [[fallthrough]];
5020   case ISD::SRA:
5021   case ISD::SHL:
5022     if (tryShiftAmountMod(Node))
5023       return;
5024     break;
5025 
5026   case X86ISD::VPTERNLOG: {
5027     uint8_t Imm = cast<ConstantSDNode>(Node->getOperand(3))->getZExtValue();
5028     if (matchVPTERNLOG(Node, Node, Node, Node, Node->getOperand(0),
5029                        Node->getOperand(1), Node->getOperand(2), Imm))
5030       return;
5031     break;
5032   }
5033 
5034   case X86ISD::ANDNP:
5035     if (tryVPTERNLOG(Node))
5036       return;
5037     break;
5038 
5039   case ISD::AND:
5040     if (NVT.isVector() && NVT.getVectorElementType() == MVT::i1) {
5041       // Try to form a masked VPTESTM. Operands can be in either order.
5042       SDValue N0 = Node->getOperand(0);
5043       SDValue N1 = Node->getOperand(1);
5044       if (N0.getOpcode() == ISD::SETCC && N0.hasOneUse() &&
5045           tryVPTESTM(Node, N0, N1))
5046         return;
5047       if (N1.getOpcode() == ISD::SETCC && N1.hasOneUse() &&
5048           tryVPTESTM(Node, N1, N0))
5049         return;
5050     }
5051 
5052     if (MachineSDNode *NewNode = matchBEXTRFromAndImm(Node)) {
5053       ReplaceUses(SDValue(Node, 0), SDValue(NewNode, 0));
5054       CurDAG->RemoveDeadNode(Node);
5055       return;
5056     }
5057     if (matchBitExtract(Node))
5058       return;
5059     if (AndImmShrink && shrinkAndImmediate(Node))
5060       return;
5061 
5062     [[fallthrough]];
5063   case ISD::OR:
5064   case ISD::XOR:
5065     if (tryShrinkShlLogicImm(Node))
5066       return;
5067     if (Opcode == ISD::OR && tryMatchBitSelect(Node))
5068       return;
5069     if (tryVPTERNLOG(Node))
5070       return;
5071 
5072     [[fallthrough]];
5073   case ISD::ADD:
5074     if (Opcode == ISD::ADD && matchBitExtract(Node))
5075       return;
5076     [[fallthrough]];
5077   case ISD::SUB: {
5078     // Try to avoid folding immediates with multiple uses for optsize.
5079     // This code tries to select to register form directly to avoid going
5080     // through the isel table which might fold the immediate. We can't change
5081     // the patterns on the add/sub/and/or/xor with immediate paterns in the
5082     // tablegen files to check immediate use count without making the patterns
5083     // unavailable to the fast-isel table.
5084     if (!CurDAG->shouldOptForSize())
5085       break;
5086 
5087     // Only handle i8/i16/i32/i64.
5088     if (NVT != MVT::i8 && NVT != MVT::i16 && NVT != MVT::i32 && NVT != MVT::i64)
5089       break;
5090 
5091     SDValue N0 = Node->getOperand(0);
5092     SDValue N1 = Node->getOperand(1);
5093 
5094     auto *Cst = dyn_cast<ConstantSDNode>(N1);
5095     if (!Cst)
5096       break;
5097 
5098     int64_t Val = Cst->getSExtValue();
5099 
5100     // Make sure its an immediate that is considered foldable.
5101     // FIXME: Handle unsigned 32 bit immediates for 64-bit AND.
5102     if (!isInt<8>(Val) && !isInt<32>(Val))
5103       break;
5104 
5105     // If this can match to INC/DEC, let it go.
5106     if (Opcode == ISD::ADD && (Val == 1 || Val == -1))
5107       break;
5108 
5109     // Check if we should avoid folding this immediate.
5110     if (!shouldAvoidImmediateInstFormsForSize(N1.getNode()))
5111       break;
5112 
5113     // We should not fold the immediate. So we need a register form instead.
5114     unsigned ROpc, MOpc;
5115     switch (NVT.SimpleTy) {
5116     default: llvm_unreachable("Unexpected VT!");
5117     case MVT::i8:
5118       switch (Opcode) {
5119       default: llvm_unreachable("Unexpected opcode!");
5120       case ISD::ADD: ROpc = X86::ADD8rr; MOpc = X86::ADD8rm; break;
5121       case ISD::SUB: ROpc = X86::SUB8rr; MOpc = X86::SUB8rm; break;
5122       case ISD::AND: ROpc = X86::AND8rr; MOpc = X86::AND8rm; break;
5123       case ISD::OR:  ROpc = X86::OR8rr;  MOpc = X86::OR8rm;  break;
5124       case ISD::XOR: ROpc = X86::XOR8rr; MOpc = X86::XOR8rm; break;
5125       }
5126       break;
5127     case MVT::i16:
5128       switch (Opcode) {
5129       default: llvm_unreachable("Unexpected opcode!");
5130       case ISD::ADD: ROpc = X86::ADD16rr; MOpc = X86::ADD16rm; break;
5131       case ISD::SUB: ROpc = X86::SUB16rr; MOpc = X86::SUB16rm; break;
5132       case ISD::AND: ROpc = X86::AND16rr; MOpc = X86::AND16rm; break;
5133       case ISD::OR:  ROpc = X86::OR16rr;  MOpc = X86::OR16rm;  break;
5134       case ISD::XOR: ROpc = X86::XOR16rr; MOpc = X86::XOR16rm; break;
5135       }
5136       break;
5137     case MVT::i32:
5138       switch (Opcode) {
5139       default: llvm_unreachable("Unexpected opcode!");
5140       case ISD::ADD: ROpc = X86::ADD32rr; MOpc = X86::ADD32rm; break;
5141       case ISD::SUB: ROpc = X86::SUB32rr; MOpc = X86::SUB32rm; break;
5142       case ISD::AND: ROpc = X86::AND32rr; MOpc = X86::AND32rm; break;
5143       case ISD::OR:  ROpc = X86::OR32rr;  MOpc = X86::OR32rm;  break;
5144       case ISD::XOR: ROpc = X86::XOR32rr; MOpc = X86::XOR32rm; break;
5145       }
5146       break;
5147     case MVT::i64:
5148       switch (Opcode) {
5149       default: llvm_unreachable("Unexpected opcode!");
5150       case ISD::ADD: ROpc = X86::ADD64rr; MOpc = X86::ADD64rm; break;
5151       case ISD::SUB: ROpc = X86::SUB64rr; MOpc = X86::SUB64rm; break;
5152       case ISD::AND: ROpc = X86::AND64rr; MOpc = X86::AND64rm; break;
5153       case ISD::OR:  ROpc = X86::OR64rr;  MOpc = X86::OR64rm;  break;
5154       case ISD::XOR: ROpc = X86::XOR64rr; MOpc = X86::XOR64rm; break;
5155       }
5156       break;
5157     }
5158 
5159     // Ok this is a AND/OR/XOR/ADD/SUB with constant.
5160 
5161     // If this is a not a subtract, we can still try to fold a load.
5162     if (Opcode != ISD::SUB) {
5163       SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
5164       if (tryFoldLoad(Node, N0, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4)) {
5165         SDValue Ops[] = { N1, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, N0.getOperand(0) };
5166         SDVTList VTs = CurDAG->getVTList(NVT, MVT::i32, MVT::Other);
5167         MachineSDNode *CNode = CurDAG->getMachineNode(MOpc, dl, VTs, Ops);
5168         // Update the chain.
5169         ReplaceUses(N0.getValue(1), SDValue(CNode, 2));
5170         // Record the mem-refs
5171         CurDAG->setNodeMemRefs(CNode, {cast<LoadSDNode>(N0)->getMemOperand()});
5172         ReplaceUses(SDValue(Node, 0), SDValue(CNode, 0));
5173         CurDAG->RemoveDeadNode(Node);
5174         return;
5175       }
5176     }
5177 
5178     CurDAG->SelectNodeTo(Node, ROpc, NVT, MVT::i32, N0, N1);
5179     return;
5180   }
5181 
5182   case X86ISD::SMUL:
5183     // i16/i32/i64 are handled with isel patterns.
5184     if (NVT != MVT::i8)
5185       break;
5186     [[fallthrough]];
5187   case X86ISD::UMUL: {
5188     SDValue N0 = Node->getOperand(0);
5189     SDValue N1 = Node->getOperand(1);
5190 
5191     unsigned LoReg, ROpc, MOpc;
5192     switch (NVT.SimpleTy) {
5193     default: llvm_unreachable("Unsupported VT!");
5194     case MVT::i8:
5195       LoReg = X86::AL;
5196       ROpc = Opcode == X86ISD::SMUL ? X86::IMUL8r : X86::MUL8r;
5197       MOpc = Opcode == X86ISD::SMUL ? X86::IMUL8m : X86::MUL8m;
5198       break;
5199     case MVT::i16:
5200       LoReg = X86::AX;
5201       ROpc = X86::MUL16r;
5202       MOpc = X86::MUL16m;
5203       break;
5204     case MVT::i32:
5205       LoReg = X86::EAX;
5206       ROpc = X86::MUL32r;
5207       MOpc = X86::MUL32m;
5208       break;
5209     case MVT::i64:
5210       LoReg = X86::RAX;
5211       ROpc = X86::MUL64r;
5212       MOpc = X86::MUL64m;
5213       break;
5214     }
5215 
5216     SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
5217     bool FoldedLoad = tryFoldLoad(Node, N1, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4);
5218     // Multiply is commutative.
5219     if (!FoldedLoad) {
5220       FoldedLoad = tryFoldLoad(Node, N0, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4);
5221       if (FoldedLoad)
5222         std::swap(N0, N1);
5223     }
5224 
5225     SDValue InGlue = CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, LoReg,
5226                                           N0, SDValue()).getValue(1);
5227 
5228     MachineSDNode *CNode;
5229     if (FoldedLoad) {
5230       // i16/i32/i64 use an instruction that produces a low and high result even
5231       // though only the low result is used.
5232       SDVTList VTs;
5233       if (NVT == MVT::i8)
5234         VTs = CurDAG->getVTList(NVT, MVT::i32, MVT::Other);
5235       else
5236         VTs = CurDAG->getVTList(NVT, NVT, MVT::i32, MVT::Other);
5237 
5238       SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, N1.getOperand(0),
5239                         InGlue };
5240       CNode = CurDAG->getMachineNode(MOpc, dl, VTs, Ops);
5241 
5242       // Update the chain.
5243       ReplaceUses(N1.getValue(1), SDValue(CNode, NVT == MVT::i8 ? 2 : 3));
5244       // Record the mem-refs
5245       CurDAG->setNodeMemRefs(CNode, {cast<LoadSDNode>(N1)->getMemOperand()});
5246     } else {
5247       // i16/i32/i64 use an instruction that produces a low and high result even
5248       // though only the low result is used.
5249       SDVTList VTs;
5250       if (NVT == MVT::i8)
5251         VTs = CurDAG->getVTList(NVT, MVT::i32);
5252       else
5253         VTs = CurDAG->getVTList(NVT, NVT, MVT::i32);
5254 
5255       CNode = CurDAG->getMachineNode(ROpc, dl, VTs, {N1, InGlue});
5256     }
5257 
5258     ReplaceUses(SDValue(Node, 0), SDValue(CNode, 0));
5259     ReplaceUses(SDValue(Node, 1), SDValue(CNode, NVT == MVT::i8 ? 1 : 2));
5260     CurDAG->RemoveDeadNode(Node);
5261     return;
5262   }
5263 
5264   case ISD::SMUL_LOHI:
5265   case ISD::UMUL_LOHI: {
5266     SDValue N0 = Node->getOperand(0);
5267     SDValue N1 = Node->getOperand(1);
5268 
5269     unsigned Opc, MOpc;
5270     unsigned LoReg, HiReg;
5271     bool IsSigned = Opcode == ISD::SMUL_LOHI;
5272     bool UseMULX = !IsSigned && Subtarget->hasBMI2();
5273     bool UseMULXHi = UseMULX && SDValue(Node, 0).use_empty();
5274     switch (NVT.SimpleTy) {
5275     default: llvm_unreachable("Unsupported VT!");
5276     case MVT::i32:
5277       Opc  = UseMULXHi ? X86::MULX32Hrr :
5278              UseMULX ? X86::MULX32rr :
5279              IsSigned ? X86::IMUL32r : X86::MUL32r;
5280       MOpc = UseMULXHi ? X86::MULX32Hrm :
5281              UseMULX ? X86::MULX32rm :
5282              IsSigned ? X86::IMUL32m : X86::MUL32m;
5283       LoReg = UseMULX ? X86::EDX : X86::EAX;
5284       HiReg = X86::EDX;
5285       break;
5286     case MVT::i64:
5287       Opc  = UseMULXHi ? X86::MULX64Hrr :
5288              UseMULX ? X86::MULX64rr :
5289              IsSigned ? X86::IMUL64r : X86::MUL64r;
5290       MOpc = UseMULXHi ? X86::MULX64Hrm :
5291              UseMULX ? X86::MULX64rm :
5292              IsSigned ? X86::IMUL64m : X86::MUL64m;
5293       LoReg = UseMULX ? X86::RDX : X86::RAX;
5294       HiReg = X86::RDX;
5295       break;
5296     }
5297 
5298     SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
5299     bool foldedLoad = tryFoldLoad(Node, N1, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4);
5300     // Multiply is commutative.
5301     if (!foldedLoad) {
5302       foldedLoad = tryFoldLoad(Node, N0, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4);
5303       if (foldedLoad)
5304         std::swap(N0, N1);
5305     }
5306 
5307     SDValue InGlue = CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, LoReg,
5308                                           N0, SDValue()).getValue(1);
5309     SDValue ResHi, ResLo;
5310     if (foldedLoad) {
5311       SDValue Chain;
5312       MachineSDNode *CNode = nullptr;
5313       SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, N1.getOperand(0),
5314                         InGlue };
5315       if (UseMULXHi) {
5316         SDVTList VTs = CurDAG->getVTList(NVT, MVT::Other);
5317         CNode = CurDAG->getMachineNode(MOpc, dl, VTs, Ops);
5318         ResHi = SDValue(CNode, 0);
5319         Chain = SDValue(CNode, 1);
5320       } else if (UseMULX) {
5321         SDVTList VTs = CurDAG->getVTList(NVT, NVT, MVT::Other);
5322         CNode = CurDAG->getMachineNode(MOpc, dl, VTs, Ops);
5323         ResHi = SDValue(CNode, 0);
5324         ResLo = SDValue(CNode, 1);
5325         Chain = SDValue(CNode, 2);
5326       } else {
5327         SDVTList VTs = CurDAG->getVTList(MVT::Other, MVT::Glue);
5328         CNode = CurDAG->getMachineNode(MOpc, dl, VTs, Ops);
5329         Chain = SDValue(CNode, 0);
5330         InGlue = SDValue(CNode, 1);
5331       }
5332 
5333       // Update the chain.
5334       ReplaceUses(N1.getValue(1), Chain);
5335       // Record the mem-refs
5336       CurDAG->setNodeMemRefs(CNode, {cast<LoadSDNode>(N1)->getMemOperand()});
5337     } else {
5338       SDValue Ops[] = { N1, InGlue };
5339       if (UseMULXHi) {
5340         SDVTList VTs = CurDAG->getVTList(NVT);
5341         SDNode *CNode = CurDAG->getMachineNode(Opc, dl, VTs, Ops);
5342         ResHi = SDValue(CNode, 0);
5343       } else if (UseMULX) {
5344         SDVTList VTs = CurDAG->getVTList(NVT, NVT);
5345         SDNode *CNode = CurDAG->getMachineNode(Opc, dl, VTs, Ops);
5346         ResHi = SDValue(CNode, 0);
5347         ResLo = SDValue(CNode, 1);
5348       } else {
5349         SDVTList VTs = CurDAG->getVTList(MVT::Glue);
5350         SDNode *CNode = CurDAG->getMachineNode(Opc, dl, VTs, Ops);
5351         InGlue = SDValue(CNode, 0);
5352       }
5353     }
5354 
5355     // Copy the low half of the result, if it is needed.
5356     if (!SDValue(Node, 0).use_empty()) {
5357       if (!ResLo) {
5358         assert(LoReg && "Register for low half is not defined!");
5359         ResLo = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), dl, LoReg,
5360                                        NVT, InGlue);
5361         InGlue = ResLo.getValue(2);
5362       }
5363       ReplaceUses(SDValue(Node, 0), ResLo);
5364       LLVM_DEBUG(dbgs() << "=> "; ResLo.getNode()->dump(CurDAG);
5365                  dbgs() << '\n');
5366     }
5367     // Copy the high half of the result, if it is needed.
5368     if (!SDValue(Node, 1).use_empty()) {
5369       if (!ResHi) {
5370         assert(HiReg && "Register for high half is not defined!");
5371         ResHi = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), dl, HiReg,
5372                                        NVT, InGlue);
5373         InGlue = ResHi.getValue(2);
5374       }
5375       ReplaceUses(SDValue(Node, 1), ResHi);
5376       LLVM_DEBUG(dbgs() << "=> "; ResHi.getNode()->dump(CurDAG);
5377                  dbgs() << '\n');
5378     }
5379 
5380     CurDAG->RemoveDeadNode(Node);
5381     return;
5382   }
5383 
5384   case ISD::SDIVREM:
5385   case ISD::UDIVREM: {
5386     SDValue N0 = Node->getOperand(0);
5387     SDValue N1 = Node->getOperand(1);
5388 
5389     unsigned ROpc, MOpc;
5390     bool isSigned = Opcode == ISD::SDIVREM;
5391     if (!isSigned) {
5392       switch (NVT.SimpleTy) {
5393       default: llvm_unreachable("Unsupported VT!");
5394       case MVT::i8:  ROpc = X86::DIV8r;  MOpc = X86::DIV8m;  break;
5395       case MVT::i16: ROpc = X86::DIV16r; MOpc = X86::DIV16m; break;
5396       case MVT::i32: ROpc = X86::DIV32r; MOpc = X86::DIV32m; break;
5397       case MVT::i64: ROpc = X86::DIV64r; MOpc = X86::DIV64m; break;
5398       }
5399     } else {
5400       switch (NVT.SimpleTy) {
5401       default: llvm_unreachable("Unsupported VT!");
5402       case MVT::i8:  ROpc = X86::IDIV8r;  MOpc = X86::IDIV8m;  break;
5403       case MVT::i16: ROpc = X86::IDIV16r; MOpc = X86::IDIV16m; break;
5404       case MVT::i32: ROpc = X86::IDIV32r; MOpc = X86::IDIV32m; break;
5405       case MVT::i64: ROpc = X86::IDIV64r; MOpc = X86::IDIV64m; break;
5406       }
5407     }
5408 
5409     unsigned LoReg, HiReg, ClrReg;
5410     unsigned SExtOpcode;
5411     switch (NVT.SimpleTy) {
5412     default: llvm_unreachable("Unsupported VT!");
5413     case MVT::i8:
5414       LoReg = X86::AL;  ClrReg = HiReg = X86::AH;
5415       SExtOpcode = 0; // Not used.
5416       break;
5417     case MVT::i16:
5418       LoReg = X86::AX;  HiReg = X86::DX;
5419       ClrReg = X86::DX;
5420       SExtOpcode = X86::CWD;
5421       break;
5422     case MVT::i32:
5423       LoReg = X86::EAX; ClrReg = HiReg = X86::EDX;
5424       SExtOpcode = X86::CDQ;
5425       break;
5426     case MVT::i64:
5427       LoReg = X86::RAX; ClrReg = HiReg = X86::RDX;
5428       SExtOpcode = X86::CQO;
5429       break;
5430     }
5431 
5432     SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
5433     bool foldedLoad = tryFoldLoad(Node, N1, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4);
5434     bool signBitIsZero = CurDAG->SignBitIsZero(N0);
5435 
5436     SDValue InGlue;
5437     if (NVT == MVT::i8) {
5438       // Special case for div8, just use a move with zero extension to AX to
5439       // clear the upper 8 bits (AH).
5440       SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, Chain;
5441       MachineSDNode *Move;
5442       if (tryFoldLoad(Node, N0, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4)) {
5443         SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, N0.getOperand(0) };
5444         unsigned Opc = (isSigned && !signBitIsZero) ? X86::MOVSX16rm8
5445                                                     : X86::MOVZX16rm8;
5446         Move = CurDAG->getMachineNode(Opc, dl, MVT::i16, MVT::Other, Ops);
5447         Chain = SDValue(Move, 1);
5448         ReplaceUses(N0.getValue(1), Chain);
5449         // Record the mem-refs
5450         CurDAG->setNodeMemRefs(Move, {cast<LoadSDNode>(N0)->getMemOperand()});
5451       } else {
5452         unsigned Opc = (isSigned && !signBitIsZero) ? X86::MOVSX16rr8
5453                                                     : X86::MOVZX16rr8;
5454         Move = CurDAG->getMachineNode(Opc, dl, MVT::i16, N0);
5455         Chain = CurDAG->getEntryNode();
5456       }
5457       Chain  = CurDAG->getCopyToReg(Chain, dl, X86::AX, SDValue(Move, 0),
5458                                     SDValue());
5459       InGlue = Chain.getValue(1);
5460     } else {
5461       InGlue =
5462         CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl,
5463                              LoReg, N0, SDValue()).getValue(1);
5464       if (isSigned && !signBitIsZero) {
5465         // Sign extend the low part into the high part.
5466         InGlue =
5467           SDValue(CurDAG->getMachineNode(SExtOpcode, dl, MVT::Glue, InGlue),0);
5468       } else {
5469         // Zero out the high part, effectively zero extending the input.
5470         SDVTList VTs = CurDAG->getVTList(MVT::i32, MVT::i32);
5471         SDValue ClrNode = SDValue(
5472             CurDAG->getMachineNode(X86::MOV32r0, dl, VTs, std::nullopt), 0);
5473         switch (NVT.SimpleTy) {
5474         case MVT::i16:
5475           ClrNode =
5476               SDValue(CurDAG->getMachineNode(
5477                           TargetOpcode::EXTRACT_SUBREG, dl, MVT::i16, ClrNode,
5478                           CurDAG->getTargetConstant(X86::sub_16bit, dl,
5479                                                     MVT::i32)),
5480                       0);
5481           break;
5482         case MVT::i32:
5483           break;
5484         case MVT::i64:
5485           ClrNode =
5486               SDValue(CurDAG->getMachineNode(
5487                           TargetOpcode::SUBREG_TO_REG, dl, MVT::i64,
5488                           CurDAG->getTargetConstant(0, dl, MVT::i64), ClrNode,
5489                           CurDAG->getTargetConstant(X86::sub_32bit, dl,
5490                                                     MVT::i32)),
5491                       0);
5492           break;
5493         default:
5494           llvm_unreachable("Unexpected division source");
5495         }
5496 
5497         InGlue = CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, ClrReg,
5498                                       ClrNode, InGlue).getValue(1);
5499       }
5500     }
5501 
5502     if (foldedLoad) {
5503       SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, N1.getOperand(0),
5504                         InGlue };
5505       MachineSDNode *CNode =
5506         CurDAG->getMachineNode(MOpc, dl, MVT::Other, MVT::Glue, Ops);
5507       InGlue = SDValue(CNode, 1);
5508       // Update the chain.
5509       ReplaceUses(N1.getValue(1), SDValue(CNode, 0));
5510       // Record the mem-refs
5511       CurDAG->setNodeMemRefs(CNode, {cast<LoadSDNode>(N1)->getMemOperand()});
5512     } else {
5513       InGlue =
5514         SDValue(CurDAG->getMachineNode(ROpc, dl, MVT::Glue, N1, InGlue), 0);
5515     }
5516 
5517     // Prevent use of AH in a REX instruction by explicitly copying it to
5518     // an ABCD_L register.
5519     //
5520     // The current assumption of the register allocator is that isel
5521     // won't generate explicit references to the GR8_ABCD_H registers. If
5522     // the allocator and/or the backend get enhanced to be more robust in
5523     // that regard, this can be, and should be, removed.
5524     if (HiReg == X86::AH && !SDValue(Node, 1).use_empty()) {
5525       SDValue AHCopy = CurDAG->getRegister(X86::AH, MVT::i8);
5526       unsigned AHExtOpcode =
5527           isSigned ? X86::MOVSX32rr8_NOREX : X86::MOVZX32rr8_NOREX;
5528 
5529       SDNode *RNode = CurDAG->getMachineNode(AHExtOpcode, dl, MVT::i32,
5530                                              MVT::Glue, AHCopy, InGlue);
5531       SDValue Result(RNode, 0);
5532       InGlue = SDValue(RNode, 1);
5533 
5534       Result =
5535           CurDAG->getTargetExtractSubreg(X86::sub_8bit, dl, MVT::i8, Result);
5536 
5537       ReplaceUses(SDValue(Node, 1), Result);
5538       LLVM_DEBUG(dbgs() << "=> "; Result.getNode()->dump(CurDAG);
5539                  dbgs() << '\n');
5540     }
5541     // Copy the division (low) result, if it is needed.
5542     if (!SDValue(Node, 0).use_empty()) {
5543       SDValue Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), dl,
5544                                                 LoReg, NVT, InGlue);
5545       InGlue = Result.getValue(2);
5546       ReplaceUses(SDValue(Node, 0), Result);
5547       LLVM_DEBUG(dbgs() << "=> "; Result.getNode()->dump(CurDAG);
5548                  dbgs() << '\n');
5549     }
5550     // Copy the remainder (high) result, if it is needed.
5551     if (!SDValue(Node, 1).use_empty()) {
5552       SDValue Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), dl,
5553                                               HiReg, NVT, InGlue);
5554       InGlue = Result.getValue(2);
5555       ReplaceUses(SDValue(Node, 1), Result);
5556       LLVM_DEBUG(dbgs() << "=> "; Result.getNode()->dump(CurDAG);
5557                  dbgs() << '\n');
5558     }
5559     CurDAG->RemoveDeadNode(Node);
5560     return;
5561   }
5562 
5563   case X86ISD::FCMP:
5564   case X86ISD::STRICT_FCMP:
5565   case X86ISD::STRICT_FCMPS: {
5566     bool IsStrictCmp = Node->getOpcode() == X86ISD::STRICT_FCMP ||
5567                        Node->getOpcode() == X86ISD::STRICT_FCMPS;
5568     SDValue N0 = Node->getOperand(IsStrictCmp ? 1 : 0);
5569     SDValue N1 = Node->getOperand(IsStrictCmp ? 2 : 1);
5570 
5571     // Save the original VT of the compare.
5572     MVT CmpVT = N0.getSimpleValueType();
5573 
5574     // Floating point needs special handling if we don't have FCOMI.
5575     if (Subtarget->canUseCMOV())
5576       break;
5577 
5578     bool IsSignaling = Node->getOpcode() == X86ISD::STRICT_FCMPS;
5579 
5580     unsigned Opc;
5581     switch (CmpVT.SimpleTy) {
5582     default: llvm_unreachable("Unexpected type!");
5583     case MVT::f32:
5584       Opc = IsSignaling ? X86::COM_Fpr32 : X86::UCOM_Fpr32;
5585       break;
5586     case MVT::f64:
5587       Opc = IsSignaling ? X86::COM_Fpr64 : X86::UCOM_Fpr64;
5588       break;
5589     case MVT::f80:
5590       Opc = IsSignaling ? X86::COM_Fpr80 : X86::UCOM_Fpr80;
5591       break;
5592     }
5593 
5594     SDValue Chain =
5595         IsStrictCmp ? Node->getOperand(0) : CurDAG->getEntryNode();
5596     SDValue Glue;
5597     if (IsStrictCmp) {
5598       SDVTList VTs = CurDAG->getVTList(MVT::Other, MVT::Glue);
5599       Chain = SDValue(CurDAG->getMachineNode(Opc, dl, VTs, {N0, N1, Chain}), 0);
5600       Glue = Chain.getValue(1);
5601     } else {
5602       Glue = SDValue(CurDAG->getMachineNode(Opc, dl, MVT::Glue, N0, N1), 0);
5603     }
5604 
5605     // Move FPSW to AX.
5606     SDValue FNSTSW =
5607         SDValue(CurDAG->getMachineNode(X86::FNSTSW16r, dl, MVT::i16, Glue), 0);
5608 
5609     // Extract upper 8-bits of AX.
5610     SDValue Extract =
5611         CurDAG->getTargetExtractSubreg(X86::sub_8bit_hi, dl, MVT::i8, FNSTSW);
5612 
5613     // Move AH into flags.
5614     // Some 64-bit targets lack SAHF support, but they do support FCOMI.
5615     assert(Subtarget->canUseLAHFSAHF() &&
5616            "Target doesn't support SAHF or FCOMI?");
5617     SDValue AH = CurDAG->getCopyToReg(Chain, dl, X86::AH, Extract, SDValue());
5618     Chain = AH;
5619     SDValue SAHF = SDValue(
5620         CurDAG->getMachineNode(X86::SAHF, dl, MVT::i32, AH.getValue(1)), 0);
5621 
5622     if (IsStrictCmp)
5623       ReplaceUses(SDValue(Node, 1), Chain);
5624 
5625     ReplaceUses(SDValue(Node, 0), SAHF);
5626     CurDAG->RemoveDeadNode(Node);
5627     return;
5628   }
5629 
5630   case X86ISD::CMP: {
5631     SDValue N0 = Node->getOperand(0);
5632     SDValue N1 = Node->getOperand(1);
5633 
5634     // Optimizations for TEST compares.
5635     if (!isNullConstant(N1))
5636       break;
5637 
5638     // Save the original VT of the compare.
5639     MVT CmpVT = N0.getSimpleValueType();
5640 
5641     // If we are comparing (and (shr X, C, Mask) with 0, emit a BEXTR followed
5642     // by a test instruction. The test should be removed later by
5643     // analyzeCompare if we are using only the zero flag.
5644     // TODO: Should we check the users and use the BEXTR flags directly?
5645     if (N0.getOpcode() == ISD::AND && N0.hasOneUse()) {
5646       if (MachineSDNode *NewNode = matchBEXTRFromAndImm(N0.getNode())) {
5647         unsigned TestOpc = CmpVT == MVT::i64 ? X86::TEST64rr
5648                                              : X86::TEST32rr;
5649         SDValue BEXTR = SDValue(NewNode, 0);
5650         NewNode = CurDAG->getMachineNode(TestOpc, dl, MVT::i32, BEXTR, BEXTR);
5651         ReplaceUses(SDValue(Node, 0), SDValue(NewNode, 0));
5652         CurDAG->RemoveDeadNode(Node);
5653         return;
5654       }
5655     }
5656 
5657     // We can peek through truncates, but we need to be careful below.
5658     if (N0.getOpcode() == ISD::TRUNCATE && N0.hasOneUse())
5659       N0 = N0.getOperand(0);
5660 
5661     // Look for (X86cmp (and $op, $imm), 0) and see if we can convert it to
5662     // use a smaller encoding.
5663     // Look past the truncate if CMP is the only use of it.
5664     if (N0.getOpcode() == ISD::AND && N0.getNode()->hasOneUse() &&
5665         N0.getValueType() != MVT::i8) {
5666       auto *MaskC = dyn_cast<ConstantSDNode>(N0.getOperand(1));
5667       if (!MaskC)
5668         break;
5669 
5670       // We may have looked through a truncate so mask off any bits that
5671       // shouldn't be part of the compare.
5672       uint64_t Mask = MaskC->getZExtValue();
5673       Mask &= maskTrailingOnes<uint64_t>(CmpVT.getScalarSizeInBits());
5674 
5675       // Check if we can replace AND+IMM{32,64} with a shift. This is possible
5676       // for masks like 0xFF000000 or 0x00FFFFFF and if we care only about the
5677       // zero flag.
5678       if (CmpVT == MVT::i64 && !isInt<8>(Mask) && isShiftedMask_64(Mask) &&
5679           onlyUsesZeroFlag(SDValue(Node, 0))) {
5680         unsigned ShiftOpcode = ISD::DELETED_NODE;
5681         unsigned ShiftAmt;
5682         unsigned SubRegIdx;
5683         MVT SubRegVT;
5684         unsigned TestOpcode;
5685         unsigned LeadingZeros = llvm::countl_zero(Mask);
5686         unsigned TrailingZeros = llvm::countr_zero(Mask);
5687 
5688         // With leading/trailing zeros, the transform is profitable if we can
5689         // eliminate a movabsq or shrink a 32-bit immediate to 8-bit without
5690         // incurring any extra register moves.
5691         bool SavesBytes = !isInt<32>(Mask) || N0.getOperand(0).hasOneUse();
5692         if (LeadingZeros == 0 && SavesBytes) {
5693           // If the mask covers the most significant bit, then we can replace
5694           // TEST+AND with a SHR and check eflags.
5695           // This emits a redundant TEST which is subsequently eliminated.
5696           ShiftOpcode = X86::SHR64ri;
5697           ShiftAmt = TrailingZeros;
5698           SubRegIdx = 0;
5699           TestOpcode = X86::TEST64rr;
5700         } else if (TrailingZeros == 0 && SavesBytes) {
5701           // If the mask covers the least significant bit, then we can replace
5702           // TEST+AND with a SHL and check eflags.
5703           // This emits a redundant TEST which is subsequently eliminated.
5704           ShiftOpcode = X86::SHL64ri;
5705           ShiftAmt = LeadingZeros;
5706           SubRegIdx = 0;
5707           TestOpcode = X86::TEST64rr;
5708         } else if (MaskC->hasOneUse() && !isInt<32>(Mask)) {
5709           // If the shifted mask extends into the high half and is 8/16/32 bits
5710           // wide, then replace it with a SHR and a TEST8rr/TEST16rr/TEST32rr.
5711           unsigned PopCount = 64 - LeadingZeros - TrailingZeros;
5712           if (PopCount == 8) {
5713             ShiftOpcode = X86::SHR64ri;
5714             ShiftAmt = TrailingZeros;
5715             SubRegIdx = X86::sub_8bit;
5716             SubRegVT = MVT::i8;
5717             TestOpcode = X86::TEST8rr;
5718           } else if (PopCount == 16) {
5719             ShiftOpcode = X86::SHR64ri;
5720             ShiftAmt = TrailingZeros;
5721             SubRegIdx = X86::sub_16bit;
5722             SubRegVT = MVT::i16;
5723             TestOpcode = X86::TEST16rr;
5724           } else if (PopCount == 32) {
5725             ShiftOpcode = X86::SHR64ri;
5726             ShiftAmt = TrailingZeros;
5727             SubRegIdx = X86::sub_32bit;
5728             SubRegVT = MVT::i32;
5729             TestOpcode = X86::TEST32rr;
5730           }
5731         }
5732         if (ShiftOpcode != ISD::DELETED_NODE) {
5733           SDValue ShiftC = CurDAG->getTargetConstant(ShiftAmt, dl, MVT::i64);
5734           SDValue Shift = SDValue(
5735               CurDAG->getMachineNode(ShiftOpcode, dl, MVT::i64, MVT::i32,
5736                                      N0.getOperand(0), ShiftC),
5737               0);
5738           if (SubRegIdx != 0) {
5739             Shift =
5740                 CurDAG->getTargetExtractSubreg(SubRegIdx, dl, SubRegVT, Shift);
5741           }
5742           MachineSDNode *Test =
5743               CurDAG->getMachineNode(TestOpcode, dl, MVT::i32, Shift, Shift);
5744           ReplaceNode(Node, Test);
5745           return;
5746         }
5747       }
5748 
5749       MVT VT;
5750       int SubRegOp;
5751       unsigned ROpc, MOpc;
5752 
5753       // For each of these checks we need to be careful if the sign flag is
5754       // being used. It is only safe to use the sign flag in two conditions,
5755       // either the sign bit in the shrunken mask is zero or the final test
5756       // size is equal to the original compare size.
5757 
5758       if (isUInt<8>(Mask) &&
5759           (!(Mask & 0x80) || CmpVT == MVT::i8 ||
5760            hasNoSignFlagUses(SDValue(Node, 0)))) {
5761         // For example, convert "testl %eax, $8" to "testb %al, $8"
5762         VT = MVT::i8;
5763         SubRegOp = X86::sub_8bit;
5764         ROpc = X86::TEST8ri;
5765         MOpc = X86::TEST8mi;
5766       } else if (OptForMinSize && isUInt<16>(Mask) &&
5767                  (!(Mask & 0x8000) || CmpVT == MVT::i16 ||
5768                   hasNoSignFlagUses(SDValue(Node, 0)))) {
5769         // For example, "testl %eax, $32776" to "testw %ax, $32776".
5770         // NOTE: We only want to form TESTW instructions if optimizing for
5771         // min size. Otherwise we only save one byte and possibly get a length
5772         // changing prefix penalty in the decoders.
5773         VT = MVT::i16;
5774         SubRegOp = X86::sub_16bit;
5775         ROpc = X86::TEST16ri;
5776         MOpc = X86::TEST16mi;
5777       } else if (isUInt<32>(Mask) && N0.getValueType() != MVT::i16 &&
5778                  ((!(Mask & 0x80000000) &&
5779                    // Without minsize 16-bit Cmps can get here so we need to
5780                    // be sure we calculate the correct sign flag if needed.
5781                    (CmpVT != MVT::i16 || !(Mask & 0x8000))) ||
5782                   CmpVT == MVT::i32 ||
5783                   hasNoSignFlagUses(SDValue(Node, 0)))) {
5784         // For example, "testq %rax, $268468232" to "testl %eax, $268468232".
5785         // NOTE: We only want to run that transform if N0 is 32 or 64 bits.
5786         // Otherwize, we find ourselves in a position where we have to do
5787         // promotion. If previous passes did not promote the and, we assume
5788         // they had a good reason not to and do not promote here.
5789         VT = MVT::i32;
5790         SubRegOp = X86::sub_32bit;
5791         ROpc = X86::TEST32ri;
5792         MOpc = X86::TEST32mi;
5793       } else {
5794         // No eligible transformation was found.
5795         break;
5796       }
5797 
5798       SDValue Imm = CurDAG->getTargetConstant(Mask, dl, VT);
5799       SDValue Reg = N0.getOperand(0);
5800 
5801       // Emit a testl or testw.
5802       MachineSDNode *NewNode;
5803       SDValue Tmp0, Tmp1, Tmp2, Tmp3, Tmp4;
5804       if (tryFoldLoad(Node, N0.getNode(), Reg, Tmp0, Tmp1, Tmp2, Tmp3, Tmp4)) {
5805         if (auto *LoadN = dyn_cast<LoadSDNode>(N0.getOperand(0).getNode())) {
5806           if (!LoadN->isSimple()) {
5807             unsigned NumVolBits = LoadN->getValueType(0).getSizeInBits();
5808             if ((MOpc == X86::TEST8mi && NumVolBits != 8) ||
5809                 (MOpc == X86::TEST16mi && NumVolBits != 16) ||
5810                 (MOpc == X86::TEST32mi && NumVolBits != 32))
5811               break;
5812           }
5813         }
5814         SDValue Ops[] = { Tmp0, Tmp1, Tmp2, Tmp3, Tmp4, Imm,
5815                           Reg.getOperand(0) };
5816         NewNode = CurDAG->getMachineNode(MOpc, dl, MVT::i32, MVT::Other, Ops);
5817         // Update the chain.
5818         ReplaceUses(Reg.getValue(1), SDValue(NewNode, 1));
5819         // Record the mem-refs
5820         CurDAG->setNodeMemRefs(NewNode,
5821                                {cast<LoadSDNode>(Reg)->getMemOperand()});
5822       } else {
5823         // Extract the subregister if necessary.
5824         if (N0.getValueType() != VT)
5825           Reg = CurDAG->getTargetExtractSubreg(SubRegOp, dl, VT, Reg);
5826 
5827         NewNode = CurDAG->getMachineNode(ROpc, dl, MVT::i32, Reg, Imm);
5828       }
5829       // Replace CMP with TEST.
5830       ReplaceNode(Node, NewNode);
5831       return;
5832     }
5833     break;
5834   }
5835   case X86ISD::PCMPISTR: {
5836     if (!Subtarget->hasSSE42())
5837       break;
5838 
5839     bool NeedIndex = !SDValue(Node, 0).use_empty();
5840     bool NeedMask = !SDValue(Node, 1).use_empty();
5841     // We can't fold a load if we are going to make two instructions.
5842     bool MayFoldLoad = !NeedIndex || !NeedMask;
5843 
5844     MachineSDNode *CNode;
5845     if (NeedMask) {
5846       unsigned ROpc = Subtarget->hasAVX() ? X86::VPCMPISTRMrr : X86::PCMPISTRMrr;
5847       unsigned MOpc = Subtarget->hasAVX() ? X86::VPCMPISTRMrm : X86::PCMPISTRMrm;
5848       CNode = emitPCMPISTR(ROpc, MOpc, MayFoldLoad, dl, MVT::v16i8, Node);
5849       ReplaceUses(SDValue(Node, 1), SDValue(CNode, 0));
5850     }
5851     if (NeedIndex || !NeedMask) {
5852       unsigned ROpc = Subtarget->hasAVX() ? X86::VPCMPISTRIrr : X86::PCMPISTRIrr;
5853       unsigned MOpc = Subtarget->hasAVX() ? X86::VPCMPISTRIrm : X86::PCMPISTRIrm;
5854       CNode = emitPCMPISTR(ROpc, MOpc, MayFoldLoad, dl, MVT::i32, Node);
5855       ReplaceUses(SDValue(Node, 0), SDValue(CNode, 0));
5856     }
5857 
5858     // Connect the flag usage to the last instruction created.
5859     ReplaceUses(SDValue(Node, 2), SDValue(CNode, 1));
5860     CurDAG->RemoveDeadNode(Node);
5861     return;
5862   }
5863   case X86ISD::PCMPESTR: {
5864     if (!Subtarget->hasSSE42())
5865       break;
5866 
5867     // Copy the two implicit register inputs.
5868     SDValue InGlue = CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, X86::EAX,
5869                                           Node->getOperand(1),
5870                                           SDValue()).getValue(1);
5871     InGlue = CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, X86::EDX,
5872                                   Node->getOperand(3), InGlue).getValue(1);
5873 
5874     bool NeedIndex = !SDValue(Node, 0).use_empty();
5875     bool NeedMask = !SDValue(Node, 1).use_empty();
5876     // We can't fold a load if we are going to make two instructions.
5877     bool MayFoldLoad = !NeedIndex || !NeedMask;
5878 
5879     MachineSDNode *CNode;
5880     if (NeedMask) {
5881       unsigned ROpc = Subtarget->hasAVX() ? X86::VPCMPESTRMrr : X86::PCMPESTRMrr;
5882       unsigned MOpc = Subtarget->hasAVX() ? X86::VPCMPESTRMrm : X86::PCMPESTRMrm;
5883       CNode = emitPCMPESTR(ROpc, MOpc, MayFoldLoad, dl, MVT::v16i8, Node,
5884                            InGlue);
5885       ReplaceUses(SDValue(Node, 1), SDValue(CNode, 0));
5886     }
5887     if (NeedIndex || !NeedMask) {
5888       unsigned ROpc = Subtarget->hasAVX() ? X86::VPCMPESTRIrr : X86::PCMPESTRIrr;
5889       unsigned MOpc = Subtarget->hasAVX() ? X86::VPCMPESTRIrm : X86::PCMPESTRIrm;
5890       CNode = emitPCMPESTR(ROpc, MOpc, MayFoldLoad, dl, MVT::i32, Node, InGlue);
5891       ReplaceUses(SDValue(Node, 0), SDValue(CNode, 0));
5892     }
5893     // Connect the flag usage to the last instruction created.
5894     ReplaceUses(SDValue(Node, 2), SDValue(CNode, 1));
5895     CurDAG->RemoveDeadNode(Node);
5896     return;
5897   }
5898 
5899   case ISD::SETCC: {
5900     if (NVT.isVector() && tryVPTESTM(Node, SDValue(Node, 0), SDValue()))
5901       return;
5902 
5903     break;
5904   }
5905 
5906   case ISD::STORE:
5907     if (foldLoadStoreIntoMemOperand(Node))
5908       return;
5909     break;
5910 
5911   case X86ISD::SETCC_CARRY: {
5912     MVT VT = Node->getSimpleValueType(0);
5913     SDValue Result;
5914     if (Subtarget->hasSBBDepBreaking()) {
5915       // We have to do this manually because tblgen will put the eflags copy in
5916       // the wrong place if we use an extract_subreg in the pattern.
5917       // Copy flags to the EFLAGS register and glue it to next node.
5918       SDValue EFLAGS =
5919           CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, X86::EFLAGS,
5920                                Node->getOperand(1), SDValue());
5921 
5922       // Create a 64-bit instruction if the result is 64-bits otherwise use the
5923       // 32-bit version.
5924       unsigned Opc = VT == MVT::i64 ? X86::SETB_C64r : X86::SETB_C32r;
5925       MVT SetVT = VT == MVT::i64 ? MVT::i64 : MVT::i32;
5926       Result = SDValue(
5927           CurDAG->getMachineNode(Opc, dl, SetVT, EFLAGS, EFLAGS.getValue(1)),
5928           0);
5929     } else {
5930       // The target does not recognize sbb with the same reg operand as a
5931       // no-source idiom, so we explicitly zero the input values.
5932       Result = getSBBZero(Node);
5933     }
5934 
5935     // For less than 32-bits we need to extract from the 32-bit node.
5936     if (VT == MVT::i8 || VT == MVT::i16) {
5937       int SubIndex = VT == MVT::i16 ? X86::sub_16bit : X86::sub_8bit;
5938       Result = CurDAG->getTargetExtractSubreg(SubIndex, dl, VT, Result);
5939     }
5940 
5941     ReplaceUses(SDValue(Node, 0), Result);
5942     CurDAG->RemoveDeadNode(Node);
5943     return;
5944   }
5945   case X86ISD::SBB: {
5946     if (isNullConstant(Node->getOperand(0)) &&
5947         isNullConstant(Node->getOperand(1))) {
5948       SDValue Result = getSBBZero(Node);
5949 
5950       // Replace the flag use.
5951       ReplaceUses(SDValue(Node, 1), Result.getValue(1));
5952 
5953       // Replace the result use.
5954       if (!SDValue(Node, 0).use_empty()) {
5955         // For less than 32-bits we need to extract from the 32-bit node.
5956         MVT VT = Node->getSimpleValueType(0);
5957         if (VT == MVT::i8 || VT == MVT::i16) {
5958           int SubIndex = VT == MVT::i16 ? X86::sub_16bit : X86::sub_8bit;
5959           Result = CurDAG->getTargetExtractSubreg(SubIndex, dl, VT, Result);
5960         }
5961         ReplaceUses(SDValue(Node, 0), Result);
5962       }
5963 
5964       CurDAG->RemoveDeadNode(Node);
5965       return;
5966     }
5967     break;
5968   }
5969   case X86ISD::MGATHER: {
5970     auto *Mgt = cast<X86MaskedGatherSDNode>(Node);
5971     SDValue IndexOp = Mgt->getIndex();
5972     SDValue Mask = Mgt->getMask();
5973     MVT IndexVT = IndexOp.getSimpleValueType();
5974     MVT ValueVT = Node->getSimpleValueType(0);
5975     MVT MaskVT = Mask.getSimpleValueType();
5976 
5977     // This is just to prevent crashes if the nodes are malformed somehow. We're
5978     // otherwise only doing loose type checking in here based on type what
5979     // a type constraint would say just like table based isel.
5980     if (!ValueVT.isVector() || !MaskVT.isVector())
5981       break;
5982 
5983     unsigned NumElts = ValueVT.getVectorNumElements();
5984     MVT ValueSVT = ValueVT.getVectorElementType();
5985 
5986     bool IsFP = ValueSVT.isFloatingPoint();
5987     unsigned EltSize = ValueSVT.getSizeInBits();
5988 
5989     unsigned Opc = 0;
5990     bool AVX512Gather = MaskVT.getVectorElementType() == MVT::i1;
5991     if (AVX512Gather) {
5992       if (IndexVT == MVT::v4i32 && NumElts == 4 && EltSize == 32)
5993         Opc = IsFP ? X86::VGATHERDPSZ128rm : X86::VPGATHERDDZ128rm;
5994       else if (IndexVT == MVT::v8i32 && NumElts == 8 && EltSize == 32)
5995         Opc = IsFP ? X86::VGATHERDPSZ256rm : X86::VPGATHERDDZ256rm;
5996       else if (IndexVT == MVT::v16i32 && NumElts == 16 && EltSize == 32)
5997         Opc = IsFP ? X86::VGATHERDPSZrm : X86::VPGATHERDDZrm;
5998       else if (IndexVT == MVT::v4i32 && NumElts == 2 && EltSize == 64)
5999         Opc = IsFP ? X86::VGATHERDPDZ128rm : X86::VPGATHERDQZ128rm;
6000       else if (IndexVT == MVT::v4i32 && NumElts == 4 && EltSize == 64)
6001         Opc = IsFP ? X86::VGATHERDPDZ256rm : X86::VPGATHERDQZ256rm;
6002       else if (IndexVT == MVT::v8i32 && NumElts == 8 && EltSize == 64)
6003         Opc = IsFP ? X86::VGATHERDPDZrm : X86::VPGATHERDQZrm;
6004       else if (IndexVT == MVT::v2i64 && NumElts == 4 && EltSize == 32)
6005         Opc = IsFP ? X86::VGATHERQPSZ128rm : X86::VPGATHERQDZ128rm;
6006       else if (IndexVT == MVT::v4i64 && NumElts == 4 && EltSize == 32)
6007         Opc = IsFP ? X86::VGATHERQPSZ256rm : X86::VPGATHERQDZ256rm;
6008       else if (IndexVT == MVT::v8i64 && NumElts == 8 && EltSize == 32)
6009         Opc = IsFP ? X86::VGATHERQPSZrm : X86::VPGATHERQDZrm;
6010       else if (IndexVT == MVT::v2i64 && NumElts == 2 && EltSize == 64)
6011         Opc = IsFP ? X86::VGATHERQPDZ128rm : X86::VPGATHERQQZ128rm;
6012       else if (IndexVT == MVT::v4i64 && NumElts == 4 && EltSize == 64)
6013         Opc = IsFP ? X86::VGATHERQPDZ256rm : X86::VPGATHERQQZ256rm;
6014       else if (IndexVT == MVT::v8i64 && NumElts == 8 && EltSize == 64)
6015         Opc = IsFP ? X86::VGATHERQPDZrm : X86::VPGATHERQQZrm;
6016     } else {
6017       assert(EVT(MaskVT) == EVT(ValueVT).changeVectorElementTypeToInteger() &&
6018              "Unexpected mask VT!");
6019       if (IndexVT == MVT::v4i32 && NumElts == 4 && EltSize == 32)
6020         Opc = IsFP ? X86::VGATHERDPSrm : X86::VPGATHERDDrm;
6021       else if (IndexVT == MVT::v8i32 && NumElts == 8 && EltSize == 32)
6022         Opc = IsFP ? X86::VGATHERDPSYrm : X86::VPGATHERDDYrm;
6023       else if (IndexVT == MVT::v4i32 && NumElts == 2 && EltSize == 64)
6024         Opc = IsFP ? X86::VGATHERDPDrm : X86::VPGATHERDQrm;
6025       else if (IndexVT == MVT::v4i32 && NumElts == 4 && EltSize == 64)
6026         Opc = IsFP ? X86::VGATHERDPDYrm : X86::VPGATHERDQYrm;
6027       else if (IndexVT == MVT::v2i64 && NumElts == 4 && EltSize == 32)
6028         Opc = IsFP ? X86::VGATHERQPSrm : X86::VPGATHERQDrm;
6029       else if (IndexVT == MVT::v4i64 && NumElts == 4 && EltSize == 32)
6030         Opc = IsFP ? X86::VGATHERQPSYrm : X86::VPGATHERQDYrm;
6031       else if (IndexVT == MVT::v2i64 && NumElts == 2 && EltSize == 64)
6032         Opc = IsFP ? X86::VGATHERQPDrm : X86::VPGATHERQQrm;
6033       else if (IndexVT == MVT::v4i64 && NumElts == 4 && EltSize == 64)
6034         Opc = IsFP ? X86::VGATHERQPDYrm : X86::VPGATHERQQYrm;
6035     }
6036 
6037     if (!Opc)
6038       break;
6039 
6040     SDValue Base, Scale, Index, Disp, Segment;
6041     if (!selectVectorAddr(Mgt, Mgt->getBasePtr(), IndexOp, Mgt->getScale(),
6042                           Base, Scale, Index, Disp, Segment))
6043       break;
6044 
6045     SDValue PassThru = Mgt->getPassThru();
6046     SDValue Chain = Mgt->getChain();
6047     // Gather instructions have a mask output not in the ISD node.
6048     SDVTList VTs = CurDAG->getVTList(ValueVT, MaskVT, MVT::Other);
6049 
6050     MachineSDNode *NewNode;
6051     if (AVX512Gather) {
6052       SDValue Ops[] = {PassThru, Mask, Base,    Scale,
6053                        Index,    Disp, Segment, Chain};
6054       NewNode = CurDAG->getMachineNode(Opc, SDLoc(dl), VTs, Ops);
6055     } else {
6056       SDValue Ops[] = {PassThru, Base,    Scale, Index,
6057                        Disp,     Segment, Mask,  Chain};
6058       NewNode = CurDAG->getMachineNode(Opc, SDLoc(dl), VTs, Ops);
6059     }
6060     CurDAG->setNodeMemRefs(NewNode, {Mgt->getMemOperand()});
6061     ReplaceUses(SDValue(Node, 0), SDValue(NewNode, 0));
6062     ReplaceUses(SDValue(Node, 1), SDValue(NewNode, 2));
6063     CurDAG->RemoveDeadNode(Node);
6064     return;
6065   }
6066   case X86ISD::MSCATTER: {
6067     auto *Sc = cast<X86MaskedScatterSDNode>(Node);
6068     SDValue Value = Sc->getValue();
6069     SDValue IndexOp = Sc->getIndex();
6070     MVT IndexVT = IndexOp.getSimpleValueType();
6071     MVT ValueVT = Value.getSimpleValueType();
6072 
6073     // This is just to prevent crashes if the nodes are malformed somehow. We're
6074     // otherwise only doing loose type checking in here based on type what
6075     // a type constraint would say just like table based isel.
6076     if (!ValueVT.isVector())
6077       break;
6078 
6079     unsigned NumElts = ValueVT.getVectorNumElements();
6080     MVT ValueSVT = ValueVT.getVectorElementType();
6081 
6082     bool IsFP = ValueSVT.isFloatingPoint();
6083     unsigned EltSize = ValueSVT.getSizeInBits();
6084 
6085     unsigned Opc;
6086     if (IndexVT == MVT::v4i32 && NumElts == 4 && EltSize == 32)
6087       Opc = IsFP ? X86::VSCATTERDPSZ128mr : X86::VPSCATTERDDZ128mr;
6088     else if (IndexVT == MVT::v8i32 && NumElts == 8 && EltSize == 32)
6089       Opc = IsFP ? X86::VSCATTERDPSZ256mr : X86::VPSCATTERDDZ256mr;
6090     else if (IndexVT == MVT::v16i32 && NumElts == 16 && EltSize == 32)
6091       Opc = IsFP ? X86::VSCATTERDPSZmr : X86::VPSCATTERDDZmr;
6092     else if (IndexVT == MVT::v4i32 && NumElts == 2 && EltSize == 64)
6093       Opc = IsFP ? X86::VSCATTERDPDZ128mr : X86::VPSCATTERDQZ128mr;
6094     else if (IndexVT == MVT::v4i32 && NumElts == 4 && EltSize == 64)
6095       Opc = IsFP ? X86::VSCATTERDPDZ256mr : X86::VPSCATTERDQZ256mr;
6096     else if (IndexVT == MVT::v8i32 && NumElts == 8 && EltSize == 64)
6097       Opc = IsFP ? X86::VSCATTERDPDZmr : X86::VPSCATTERDQZmr;
6098     else if (IndexVT == MVT::v2i64 && NumElts == 4 && EltSize == 32)
6099       Opc = IsFP ? X86::VSCATTERQPSZ128mr : X86::VPSCATTERQDZ128mr;
6100     else if (IndexVT == MVT::v4i64 && NumElts == 4 && EltSize == 32)
6101       Opc = IsFP ? X86::VSCATTERQPSZ256mr : X86::VPSCATTERQDZ256mr;
6102     else if (IndexVT == MVT::v8i64 && NumElts == 8 && EltSize == 32)
6103       Opc = IsFP ? X86::VSCATTERQPSZmr : X86::VPSCATTERQDZmr;
6104     else if (IndexVT == MVT::v2i64 && NumElts == 2 && EltSize == 64)
6105       Opc = IsFP ? X86::VSCATTERQPDZ128mr : X86::VPSCATTERQQZ128mr;
6106     else if (IndexVT == MVT::v4i64 && NumElts == 4 && EltSize == 64)
6107       Opc = IsFP ? X86::VSCATTERQPDZ256mr : X86::VPSCATTERQQZ256mr;
6108     else if (IndexVT == MVT::v8i64 && NumElts == 8 && EltSize == 64)
6109       Opc = IsFP ? X86::VSCATTERQPDZmr : X86::VPSCATTERQQZmr;
6110     else
6111       break;
6112 
6113     SDValue Base, Scale, Index, Disp, Segment;
6114     if (!selectVectorAddr(Sc, Sc->getBasePtr(), IndexOp, Sc->getScale(),
6115                           Base, Scale, Index, Disp, Segment))
6116       break;
6117 
6118     SDValue Mask = Sc->getMask();
6119     SDValue Chain = Sc->getChain();
6120     // Scatter instructions have a mask output not in the ISD node.
6121     SDVTList VTs = CurDAG->getVTList(Mask.getValueType(), MVT::Other);
6122     SDValue Ops[] = {Base, Scale, Index, Disp, Segment, Mask, Value, Chain};
6123 
6124     MachineSDNode *NewNode = CurDAG->getMachineNode(Opc, SDLoc(dl), VTs, Ops);
6125     CurDAG->setNodeMemRefs(NewNode, {Sc->getMemOperand()});
6126     ReplaceUses(SDValue(Node, 0), SDValue(NewNode, 1));
6127     CurDAG->RemoveDeadNode(Node);
6128     return;
6129   }
6130   case ISD::PREALLOCATED_SETUP: {
6131     auto *MFI = CurDAG->getMachineFunction().getInfo<X86MachineFunctionInfo>();
6132     auto CallId = MFI->getPreallocatedIdForCallSite(
6133         cast<SrcValueSDNode>(Node->getOperand(1))->getValue());
6134     SDValue Chain = Node->getOperand(0);
6135     SDValue CallIdValue = CurDAG->getTargetConstant(CallId, dl, MVT::i32);
6136     MachineSDNode *New = CurDAG->getMachineNode(
6137         TargetOpcode::PREALLOCATED_SETUP, dl, MVT::Other, CallIdValue, Chain);
6138     ReplaceUses(SDValue(Node, 0), SDValue(New, 0)); // Chain
6139     CurDAG->RemoveDeadNode(Node);
6140     return;
6141   }
6142   case ISD::PREALLOCATED_ARG: {
6143     auto *MFI = CurDAG->getMachineFunction().getInfo<X86MachineFunctionInfo>();
6144     auto CallId = MFI->getPreallocatedIdForCallSite(
6145         cast<SrcValueSDNode>(Node->getOperand(1))->getValue());
6146     SDValue Chain = Node->getOperand(0);
6147     SDValue CallIdValue = CurDAG->getTargetConstant(CallId, dl, MVT::i32);
6148     SDValue ArgIndex = Node->getOperand(2);
6149     SDValue Ops[3];
6150     Ops[0] = CallIdValue;
6151     Ops[1] = ArgIndex;
6152     Ops[2] = Chain;
6153     MachineSDNode *New = CurDAG->getMachineNode(
6154         TargetOpcode::PREALLOCATED_ARG, dl,
6155         CurDAG->getVTList(TLI->getPointerTy(CurDAG->getDataLayout()),
6156                           MVT::Other),
6157         Ops);
6158     ReplaceUses(SDValue(Node, 0), SDValue(New, 0)); // Arg pointer
6159     ReplaceUses(SDValue(Node, 1), SDValue(New, 1)); // Chain
6160     CurDAG->RemoveDeadNode(Node);
6161     return;
6162   }
6163   case X86ISD::AESENCWIDE128KL:
6164   case X86ISD::AESDECWIDE128KL:
6165   case X86ISD::AESENCWIDE256KL:
6166   case X86ISD::AESDECWIDE256KL: {
6167     if (!Subtarget->hasWIDEKL())
6168       break;
6169 
6170     unsigned Opcode;
6171     switch (Node->getOpcode()) {
6172     default:
6173       llvm_unreachable("Unexpected opcode!");
6174     case X86ISD::AESENCWIDE128KL:
6175       Opcode = X86::AESENCWIDE128KL;
6176       break;
6177     case X86ISD::AESDECWIDE128KL:
6178       Opcode = X86::AESDECWIDE128KL;
6179       break;
6180     case X86ISD::AESENCWIDE256KL:
6181       Opcode = X86::AESENCWIDE256KL;
6182       break;
6183     case X86ISD::AESDECWIDE256KL:
6184       Opcode = X86::AESDECWIDE256KL;
6185       break;
6186     }
6187 
6188     SDValue Chain = Node->getOperand(0);
6189     SDValue Addr = Node->getOperand(1);
6190 
6191     SDValue Base, Scale, Index, Disp, Segment;
6192     if (!selectAddr(Node, Addr, Base, Scale, Index, Disp, Segment))
6193       break;
6194 
6195     Chain = CurDAG->getCopyToReg(Chain, dl, X86::XMM0, Node->getOperand(2),
6196                                  SDValue());
6197     Chain = CurDAG->getCopyToReg(Chain, dl, X86::XMM1, Node->getOperand(3),
6198                                  Chain.getValue(1));
6199     Chain = CurDAG->getCopyToReg(Chain, dl, X86::XMM2, Node->getOperand(4),
6200                                  Chain.getValue(1));
6201     Chain = CurDAG->getCopyToReg(Chain, dl, X86::XMM3, Node->getOperand(5),
6202                                  Chain.getValue(1));
6203     Chain = CurDAG->getCopyToReg(Chain, dl, X86::XMM4, Node->getOperand(6),
6204                                  Chain.getValue(1));
6205     Chain = CurDAG->getCopyToReg(Chain, dl, X86::XMM5, Node->getOperand(7),
6206                                  Chain.getValue(1));
6207     Chain = CurDAG->getCopyToReg(Chain, dl, X86::XMM6, Node->getOperand(8),
6208                                  Chain.getValue(1));
6209     Chain = CurDAG->getCopyToReg(Chain, dl, X86::XMM7, Node->getOperand(9),
6210                                  Chain.getValue(1));
6211 
6212     MachineSDNode *Res = CurDAG->getMachineNode(
6213         Opcode, dl, Node->getVTList(),
6214         {Base, Scale, Index, Disp, Segment, Chain, Chain.getValue(1)});
6215     CurDAG->setNodeMemRefs(Res, cast<MemSDNode>(Node)->getMemOperand());
6216     ReplaceNode(Node, Res);
6217     return;
6218   }
6219   }
6220 
6221   SelectCode(Node);
6222 }
6223 
6224 bool X86DAGToDAGISel::
6225 SelectInlineAsmMemoryOperand(const SDValue &Op, unsigned ConstraintID,
6226                              std::vector<SDValue> &OutOps) {
6227   SDValue Op0, Op1, Op2, Op3, Op4;
6228   switch (ConstraintID) {
6229   default:
6230     llvm_unreachable("Unexpected asm memory constraint");
6231   case InlineAsm::Constraint_o: // offsetable        ??
6232   case InlineAsm::Constraint_v: // not offsetable    ??
6233   case InlineAsm::Constraint_m: // memory
6234   case InlineAsm::Constraint_X:
6235   case InlineAsm::Constraint_p: // address
6236     if (!selectAddr(nullptr, Op, Op0, Op1, Op2, Op3, Op4))
6237       return true;
6238     break;
6239   }
6240 
6241   OutOps.push_back(Op0);
6242   OutOps.push_back(Op1);
6243   OutOps.push_back(Op2);
6244   OutOps.push_back(Op3);
6245   OutOps.push_back(Op4);
6246   return false;
6247 }
6248 
6249 /// This pass converts a legalized DAG into a X86-specific DAG,
6250 /// ready for instruction scheduling.
6251 FunctionPass *llvm::createX86ISelDag(X86TargetMachine &TM,
6252                                      CodeGenOpt::Level OptLevel) {
6253   return new X86DAGToDAGISel(TM, OptLevel);
6254 }
6255