xref: /freebsd/contrib/llvm-project/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
1 //===- LegalizeDAG.cpp - Implement SelectionDAG::Legalize -----------------===//
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 implements the SelectionDAG::Legalize method.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/ADT/APFloat.h"
14 #include "llvm/ADT/APInt.h"
15 #include "llvm/ADT/ArrayRef.h"
16 #include "llvm/ADT/FloatingPointMode.h"
17 #include "llvm/ADT/SetVector.h"
18 #include "llvm/ADT/SmallPtrSet.h"
19 #include "llvm/ADT/SmallSet.h"
20 #include "llvm/ADT/SmallVector.h"
21 #include "llvm/Analysis/ConstantFolding.h"
22 #include "llvm/Analysis/TargetLibraryInfo.h"
23 #include "llvm/CodeGen/ISDOpcodes.h"
24 #include "llvm/CodeGen/MachineFrameInfo.h"
25 #include "llvm/CodeGen/MachineFunction.h"
26 #include "llvm/CodeGen/MachineJumpTableInfo.h"
27 #include "llvm/CodeGen/MachineMemOperand.h"
28 #include "llvm/CodeGen/RuntimeLibcallUtil.h"
29 #include "llvm/CodeGen/SelectionDAG.h"
30 #include "llvm/CodeGen/SelectionDAGNodes.h"
31 #include "llvm/CodeGen/TargetFrameLowering.h"
32 #include "llvm/CodeGen/TargetLowering.h"
33 #include "llvm/CodeGen/TargetSubtargetInfo.h"
34 #include "llvm/CodeGen/ValueTypes.h"
35 #include "llvm/CodeGenTypes/MachineValueType.h"
36 #include "llvm/IR/CallingConv.h"
37 #include "llvm/IR/Constants.h"
38 #include "llvm/IR/DataLayout.h"
39 #include "llvm/IR/DerivedTypes.h"
40 #include "llvm/IR/Function.h"
41 #include "llvm/IR/Metadata.h"
42 #include "llvm/IR/Type.h"
43 #include "llvm/Support/Casting.h"
44 #include "llvm/Support/Compiler.h"
45 #include "llvm/Support/Debug.h"
46 #include "llvm/Support/ErrorHandling.h"
47 #include "llvm/Support/MathExtras.h"
48 #include "llvm/Support/raw_ostream.h"
49 #include "llvm/Target/TargetMachine.h"
50 #include "llvm/Target/TargetOptions.h"
51 #include <cassert>
52 #include <cstdint>
53 #include <tuple>
54 #include <utility>
55 
56 using namespace llvm;
57 
58 #define DEBUG_TYPE "legalizedag"
59 
60 namespace {
61 
62 /// Keeps track of state when getting the sign of a floating-point value as an
63 /// integer.
64 struct FloatSignAsInt {
65   EVT FloatVT;
66   SDValue Chain;
67   SDValue FloatPtr;
68   SDValue IntPtr;
69   MachinePointerInfo IntPointerInfo;
70   MachinePointerInfo FloatPointerInfo;
71   SDValue IntValue;
72   APInt SignMask;
73   uint8_t SignBit;
74 };
75 
76 //===----------------------------------------------------------------------===//
77 /// This takes an arbitrary SelectionDAG as input and
78 /// hacks on it until the target machine can handle it.  This involves
79 /// eliminating value sizes the machine cannot handle (promoting small sizes to
80 /// large sizes or splitting up large values into small values) as well as
81 /// eliminating operations the machine cannot handle.
82 ///
83 /// This code also does a small amount of optimization and recognition of idioms
84 /// as part of its processing.  For example, if a target does not support a
85 /// 'setcc' instruction efficiently, but does support 'brcc' instruction, this
86 /// will attempt merge setcc and brc instructions into brcc's.
87 class SelectionDAGLegalize {
88   const TargetMachine &TM;
89   const TargetLowering &TLI;
90   SelectionDAG &DAG;
91 
92   /// The set of nodes which have already been legalized. We hold a
93   /// reference to it in order to update as necessary on node deletion.
94   SmallPtrSetImpl<SDNode *> &LegalizedNodes;
95 
96   /// A set of all the nodes updated during legalization.
97   SmallSetVector<SDNode *, 16> *UpdatedNodes;
98 
99   EVT getSetCCResultType(EVT VT) const {
100     return TLI.getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
101   }
102 
103   // Libcall insertion helpers.
104 
105 public:
106   SelectionDAGLegalize(SelectionDAG &DAG,
107                        SmallPtrSetImpl<SDNode *> &LegalizedNodes,
108                        SmallSetVector<SDNode *, 16> *UpdatedNodes = nullptr)
109       : TM(DAG.getTarget()), TLI(DAG.getTargetLoweringInfo()), DAG(DAG),
110         LegalizedNodes(LegalizedNodes), UpdatedNodes(UpdatedNodes) {}
111 
112   /// Legalizes the given operation.
113   void LegalizeOp(SDNode *Node);
114 
115 private:
116   SDValue OptimizeFloatStore(StoreSDNode *ST);
117 
118   void LegalizeLoadOps(SDNode *Node);
119   void LegalizeStoreOps(SDNode *Node);
120 
121   SDValue ExpandINSERT_VECTOR_ELT(SDValue Op);
122 
123   /// Return a vector shuffle operation which
124   /// performs the same shuffe in terms of order or result bytes, but on a type
125   /// whose vector element type is narrower than the original shuffle type.
126   /// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
127   SDValue ShuffleWithNarrowerEltType(EVT NVT, EVT VT, const SDLoc &dl,
128                                      SDValue N1, SDValue N2,
129                                      ArrayRef<int> Mask) const;
130 
131   std::pair<SDValue, SDValue> ExpandLibCall(RTLIB::Libcall LC, SDNode *Node,
132                         TargetLowering::ArgListTy &&Args, bool isSigned);
133   std::pair<SDValue, SDValue> ExpandLibCall(RTLIB::Libcall LC, SDNode *Node, bool isSigned);
134 
135   void ExpandFrexpLibCall(SDNode *Node, SmallVectorImpl<SDValue> &Results);
136   void ExpandFPLibCall(SDNode *Node, RTLIB::Libcall LC,
137                        SmallVectorImpl<SDValue> &Results);
138   void ExpandFPLibCall(SDNode *Node, RTLIB::Libcall Call_F32,
139                        RTLIB::Libcall Call_F64, RTLIB::Libcall Call_F80,
140                        RTLIB::Libcall Call_F128,
141                        RTLIB::Libcall Call_PPCF128,
142                        SmallVectorImpl<SDValue> &Results);
143   SDValue ExpandIntLibCall(SDNode *Node, bool isSigned,
144                            RTLIB::Libcall Call_I8,
145                            RTLIB::Libcall Call_I16,
146                            RTLIB::Libcall Call_I32,
147                            RTLIB::Libcall Call_I64,
148                            RTLIB::Libcall Call_I128);
149   void ExpandArgFPLibCall(SDNode *Node,
150                           RTLIB::Libcall Call_F32, RTLIB::Libcall Call_F64,
151                           RTLIB::Libcall Call_F80, RTLIB::Libcall Call_F128,
152                           RTLIB::Libcall Call_PPCF128,
153                           SmallVectorImpl<SDValue> &Results);
154   void ExpandDivRemLibCall(SDNode *Node, SmallVectorImpl<SDValue> &Results);
155   void ExpandSinCosLibCall(SDNode *Node, SmallVectorImpl<SDValue> &Results);
156 
157   SDValue EmitStackConvert(SDValue SrcOp, EVT SlotVT, EVT DestVT,
158                            const SDLoc &dl);
159   SDValue EmitStackConvert(SDValue SrcOp, EVT SlotVT, EVT DestVT,
160                            const SDLoc &dl, SDValue ChainIn);
161   SDValue ExpandBUILD_VECTOR(SDNode *Node);
162   SDValue ExpandSPLAT_VECTOR(SDNode *Node);
163   SDValue ExpandSCALAR_TO_VECTOR(SDNode *Node);
164   void ExpandDYNAMIC_STACKALLOC(SDNode *Node,
165                                 SmallVectorImpl<SDValue> &Results);
166   void getSignAsIntValue(FloatSignAsInt &State, const SDLoc &DL,
167                          SDValue Value) const;
168   SDValue modifySignAsInt(const FloatSignAsInt &State, const SDLoc &DL,
169                           SDValue NewIntValue) const;
170   SDValue ExpandFCOPYSIGN(SDNode *Node) const;
171   SDValue ExpandFABS(SDNode *Node) const;
172   SDValue ExpandFNEG(SDNode *Node) const;
173   SDValue expandLdexp(SDNode *Node) const;
174   SDValue expandFrexp(SDNode *Node) const;
175 
176   SDValue ExpandLegalINT_TO_FP(SDNode *Node, SDValue &Chain);
177   void PromoteLegalINT_TO_FP(SDNode *N, const SDLoc &dl,
178                              SmallVectorImpl<SDValue> &Results);
179   void PromoteLegalFP_TO_INT(SDNode *N, const SDLoc &dl,
180                              SmallVectorImpl<SDValue> &Results);
181   SDValue PromoteLegalFP_TO_INT_SAT(SDNode *Node, const SDLoc &dl);
182 
183   /// Implements vector reduce operation promotion.
184   ///
185   /// All vector operands are promoted to a vector type with larger element
186   /// type, and the start value is promoted to a larger scalar type. Then the
187   /// result is truncated back to the original scalar type.
188   SDValue PromoteReduction(SDNode *Node);
189 
190   SDValue ExpandPARITY(SDValue Op, const SDLoc &dl);
191 
192   SDValue ExpandExtractFromVectorThroughStack(SDValue Op);
193   SDValue ExpandInsertToVectorThroughStack(SDValue Op);
194   SDValue ExpandVectorBuildThroughStack(SDNode* Node);
195 
196   SDValue ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP);
197   SDValue ExpandConstant(ConstantSDNode *CP);
198 
199   // if ExpandNode returns false, LegalizeOp falls back to ConvertNodeToLibcall
200   bool ExpandNode(SDNode *Node);
201   void ConvertNodeToLibcall(SDNode *Node);
202   void PromoteNode(SDNode *Node);
203 
204 public:
205   // Node replacement helpers
206 
207   void ReplacedNode(SDNode *N) {
208     LegalizedNodes.erase(N);
209     if (UpdatedNodes)
210       UpdatedNodes->insert(N);
211   }
212 
213   void ReplaceNode(SDNode *Old, SDNode *New) {
214     LLVM_DEBUG(dbgs() << " ... replacing: "; Old->dump(&DAG);
215                dbgs() << "     with:      "; New->dump(&DAG));
216 
217     assert(Old->getNumValues() == New->getNumValues() &&
218            "Replacing one node with another that produces a different number "
219            "of values!");
220     DAG.ReplaceAllUsesWith(Old, New);
221     if (UpdatedNodes)
222       UpdatedNodes->insert(New);
223     ReplacedNode(Old);
224   }
225 
226   void ReplaceNode(SDValue Old, SDValue New) {
227     LLVM_DEBUG(dbgs() << " ... replacing: "; Old->dump(&DAG);
228                dbgs() << "     with:      "; New->dump(&DAG));
229 
230     DAG.ReplaceAllUsesWith(Old, New);
231     if (UpdatedNodes)
232       UpdatedNodes->insert(New.getNode());
233     ReplacedNode(Old.getNode());
234   }
235 
236   void ReplaceNode(SDNode *Old, const SDValue *New) {
237     LLVM_DEBUG(dbgs() << " ... replacing: "; Old->dump(&DAG));
238 
239     DAG.ReplaceAllUsesWith(Old, New);
240     for (unsigned i = 0, e = Old->getNumValues(); i != e; ++i) {
241       LLVM_DEBUG(dbgs() << (i == 0 ? "     with:      " : "      and:      ");
242                  New[i]->dump(&DAG));
243       if (UpdatedNodes)
244         UpdatedNodes->insert(New[i].getNode());
245     }
246     ReplacedNode(Old);
247   }
248 
249   void ReplaceNodeWithValue(SDValue Old, SDValue New) {
250     LLVM_DEBUG(dbgs() << " ... replacing: "; Old->dump(&DAG);
251                dbgs() << "     with:      "; New->dump(&DAG));
252 
253     DAG.ReplaceAllUsesOfValueWith(Old, New);
254     if (UpdatedNodes)
255       UpdatedNodes->insert(New.getNode());
256     ReplacedNode(Old.getNode());
257   }
258 };
259 
260 } // end anonymous namespace
261 
262 // Helper function that generates an MMO that considers the alignment of the
263 // stack, and the size of the stack object
264 static MachineMemOperand *getStackAlignedMMO(SDValue StackPtr,
265                                              MachineFunction &MF,
266                                              bool isObjectScalable) {
267   auto &MFI = MF.getFrameInfo();
268   int FI = cast<FrameIndexSDNode>(StackPtr)->getIndex();
269   MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(MF, FI);
270   LocationSize ObjectSize = isObjectScalable
271                                 ? LocationSize::beforeOrAfterPointer()
272                                 : LocationSize::precise(MFI.getObjectSize(FI));
273   return MF.getMachineMemOperand(PtrInfo, MachineMemOperand::MOStore,
274                                  ObjectSize, MFI.getObjectAlign(FI));
275 }
276 
277 /// Return a vector shuffle operation which
278 /// performs the same shuffle in terms of order or result bytes, but on a type
279 /// whose vector element type is narrower than the original shuffle type.
280 /// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
281 SDValue SelectionDAGLegalize::ShuffleWithNarrowerEltType(
282     EVT NVT, EVT VT, const SDLoc &dl, SDValue N1, SDValue N2,
283     ArrayRef<int> Mask) const {
284   unsigned NumMaskElts = VT.getVectorNumElements();
285   unsigned NumDestElts = NVT.getVectorNumElements();
286   unsigned NumEltsGrowth = NumDestElts / NumMaskElts;
287 
288   assert(NumEltsGrowth && "Cannot promote to vector type with fewer elts!");
289 
290   if (NumEltsGrowth == 1)
291     return DAG.getVectorShuffle(NVT, dl, N1, N2, Mask);
292 
293   SmallVector<int, 8> NewMask;
294   for (unsigned i = 0; i != NumMaskElts; ++i) {
295     int Idx = Mask[i];
296     for (unsigned j = 0; j != NumEltsGrowth; ++j) {
297       if (Idx < 0)
298         NewMask.push_back(-1);
299       else
300         NewMask.push_back(Idx * NumEltsGrowth + j);
301     }
302   }
303   assert(NewMask.size() == NumDestElts && "Non-integer NumEltsGrowth?");
304   assert(TLI.isShuffleMaskLegal(NewMask, NVT) && "Shuffle not legal?");
305   return DAG.getVectorShuffle(NVT, dl, N1, N2, NewMask);
306 }
307 
308 /// Expands the ConstantFP node to an integer constant or
309 /// a load from the constant pool.
310 SDValue
311 SelectionDAGLegalize::ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP) {
312   bool Extend = false;
313   SDLoc dl(CFP);
314 
315   // If a FP immediate is precise when represented as a float and if the
316   // target can do an extending load from float to double, we put it into
317   // the constant pool as a float, even if it's is statically typed as a
318   // double.  This shrinks FP constants and canonicalizes them for targets where
319   // an FP extending load is the same cost as a normal load (such as on the x87
320   // fp stack or PPC FP unit).
321   EVT VT = CFP->getValueType(0);
322   ConstantFP *LLVMC = const_cast<ConstantFP*>(CFP->getConstantFPValue());
323   if (!UseCP) {
324     assert((VT == MVT::f64 || VT == MVT::f32) && "Invalid type expansion");
325     return DAG.getConstant(LLVMC->getValueAPF().bitcastToAPInt(), dl,
326                            (VT == MVT::f64) ? MVT::i64 : MVT::i32);
327   }
328 
329   APFloat APF = CFP->getValueAPF();
330   EVT OrigVT = VT;
331   EVT SVT = VT;
332 
333   // We don't want to shrink SNaNs. Converting the SNaN back to its real type
334   // can cause it to be changed into a QNaN on some platforms (e.g. on SystemZ).
335   if (!APF.isSignaling()) {
336     while (SVT != MVT::f32 && SVT != MVT::f16 && SVT != MVT::bf16) {
337       SVT = (MVT::SimpleValueType)(SVT.getSimpleVT().SimpleTy - 1);
338       if (ConstantFPSDNode::isValueValidForType(SVT, APF) &&
339           // Only do this if the target has a native EXTLOAD instruction from
340           // smaller type.
341           TLI.isLoadExtLegal(ISD::EXTLOAD, OrigVT, SVT) &&
342           TLI.ShouldShrinkFPConstant(OrigVT)) {
343         Type *SType = SVT.getTypeForEVT(*DAG.getContext());
344         LLVMC = cast<ConstantFP>(ConstantFoldCastOperand(
345             Instruction::FPTrunc, LLVMC, SType, DAG.getDataLayout()));
346         VT = SVT;
347         Extend = true;
348       }
349     }
350   }
351 
352   SDValue CPIdx =
353       DAG.getConstantPool(LLVMC, TLI.getPointerTy(DAG.getDataLayout()));
354   Align Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlign();
355   if (Extend) {
356     SDValue Result = DAG.getExtLoad(
357         ISD::EXTLOAD, dl, OrigVT, DAG.getEntryNode(), CPIdx,
358         MachinePointerInfo::getConstantPool(DAG.getMachineFunction()), VT,
359         Alignment);
360     return Result;
361   }
362   SDValue Result = DAG.getLoad(
363       OrigVT, dl, DAG.getEntryNode(), CPIdx,
364       MachinePointerInfo::getConstantPool(DAG.getMachineFunction()), Alignment);
365   return Result;
366 }
367 
368 /// Expands the Constant node to a load from the constant pool.
369 SDValue SelectionDAGLegalize::ExpandConstant(ConstantSDNode *CP) {
370   SDLoc dl(CP);
371   EVT VT = CP->getValueType(0);
372   SDValue CPIdx = DAG.getConstantPool(CP->getConstantIntValue(),
373                                       TLI.getPointerTy(DAG.getDataLayout()));
374   Align Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlign();
375   SDValue Result = DAG.getLoad(
376       VT, dl, DAG.getEntryNode(), CPIdx,
377       MachinePointerInfo::getConstantPool(DAG.getMachineFunction()), Alignment);
378   return Result;
379 }
380 
381 SDValue SelectionDAGLegalize::ExpandINSERT_VECTOR_ELT(SDValue Op) {
382   SDValue Vec = Op.getOperand(0);
383   SDValue Val = Op.getOperand(1);
384   SDValue Idx = Op.getOperand(2);
385   SDLoc dl(Op);
386 
387   if (ConstantSDNode *InsertPos = dyn_cast<ConstantSDNode>(Idx)) {
388     // SCALAR_TO_VECTOR requires that the type of the value being inserted
389     // match the element type of the vector being created, except for
390     // integers in which case the inserted value can be over width.
391     EVT EltVT = Vec.getValueType().getVectorElementType();
392     if (Val.getValueType() == EltVT ||
393         (EltVT.isInteger() && Val.getValueType().bitsGE(EltVT))) {
394       SDValue ScVec = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl,
395                                   Vec.getValueType(), Val);
396 
397       unsigned NumElts = Vec.getValueType().getVectorNumElements();
398       // We generate a shuffle of InVec and ScVec, so the shuffle mask
399       // should be 0,1,2,3,4,5... with the appropriate element replaced with
400       // elt 0 of the RHS.
401       SmallVector<int, 8> ShufOps;
402       for (unsigned i = 0; i != NumElts; ++i)
403         ShufOps.push_back(i != InsertPos->getZExtValue() ? i : NumElts);
404 
405       return DAG.getVectorShuffle(Vec.getValueType(), dl, Vec, ScVec, ShufOps);
406     }
407   }
408   return ExpandInsertToVectorThroughStack(Op);
409 }
410 
411 SDValue SelectionDAGLegalize::OptimizeFloatStore(StoreSDNode* ST) {
412   if (!ISD::isNormalStore(ST))
413     return SDValue();
414 
415   LLVM_DEBUG(dbgs() << "Optimizing float store operations\n");
416   // Turn 'store float 1.0, Ptr' -> 'store int 0x12345678, Ptr'
417   // FIXME: move this to the DAG Combiner!  Note that we can't regress due
418   // to phase ordering between legalized code and the dag combiner.  This
419   // probably means that we need to integrate dag combiner and legalizer
420   // together.
421   // We generally can't do this one for long doubles.
422   SDValue Chain = ST->getChain();
423   SDValue Ptr = ST->getBasePtr();
424   SDValue Value = ST->getValue();
425   MachineMemOperand::Flags MMOFlags = ST->getMemOperand()->getFlags();
426   AAMDNodes AAInfo = ST->getAAInfo();
427   SDLoc dl(ST);
428 
429   // Don't optimise TargetConstantFP
430   if (Value.getOpcode() == ISD::TargetConstantFP)
431     return SDValue();
432 
433   if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(Value)) {
434     if (CFP->getValueType(0) == MVT::f32 &&
435         TLI.isTypeLegal(MVT::i32)) {
436       SDValue Con = DAG.getConstant(CFP->getValueAPF().
437                                       bitcastToAPInt().zextOrTrunc(32),
438                                     SDLoc(CFP), MVT::i32);
439       return DAG.getStore(Chain, dl, Con, Ptr, ST->getPointerInfo(),
440                           ST->getOriginalAlign(), MMOFlags, AAInfo);
441     }
442 
443     if (CFP->getValueType(0) == MVT::f64 &&
444         !TLI.isFPImmLegal(CFP->getValueAPF(), MVT::f64)) {
445       // If this target supports 64-bit registers, do a single 64-bit store.
446       if (TLI.isTypeLegal(MVT::i64)) {
447         SDValue Con = DAG.getConstant(CFP->getValueAPF().bitcastToAPInt().
448                                       zextOrTrunc(64), SDLoc(CFP), MVT::i64);
449         return DAG.getStore(Chain, dl, Con, Ptr, ST->getPointerInfo(),
450                             ST->getOriginalAlign(), MMOFlags, AAInfo);
451       }
452 
453       if (TLI.isTypeLegal(MVT::i32) && !ST->isVolatile()) {
454         // Otherwise, if the target supports 32-bit registers, use 2 32-bit
455         // stores.  If the target supports neither 32- nor 64-bits, this
456         // xform is certainly not worth it.
457         const APInt &IntVal = CFP->getValueAPF().bitcastToAPInt();
458         SDValue Lo = DAG.getConstant(IntVal.trunc(32), dl, MVT::i32);
459         SDValue Hi = DAG.getConstant(IntVal.lshr(32).trunc(32), dl, MVT::i32);
460         if (DAG.getDataLayout().isBigEndian())
461           std::swap(Lo, Hi);
462 
463         Lo = DAG.getStore(Chain, dl, Lo, Ptr, ST->getPointerInfo(),
464                           ST->getOriginalAlign(), MMOFlags, AAInfo);
465         Ptr = DAG.getMemBasePlusOffset(Ptr, TypeSize::getFixed(4), dl);
466         Hi = DAG.getStore(Chain, dl, Hi, Ptr,
467                           ST->getPointerInfo().getWithOffset(4),
468                           ST->getOriginalAlign(), MMOFlags, AAInfo);
469 
470         return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
471       }
472     }
473   }
474   return SDValue();
475 }
476 
477 void SelectionDAGLegalize::LegalizeStoreOps(SDNode *Node) {
478   StoreSDNode *ST = cast<StoreSDNode>(Node);
479   SDValue Chain = ST->getChain();
480   SDValue Ptr = ST->getBasePtr();
481   SDLoc dl(Node);
482 
483   MachineMemOperand::Flags MMOFlags = ST->getMemOperand()->getFlags();
484   AAMDNodes AAInfo = ST->getAAInfo();
485 
486   if (!ST->isTruncatingStore()) {
487     LLVM_DEBUG(dbgs() << "Legalizing store operation\n");
488     if (SDNode *OptStore = OptimizeFloatStore(ST).getNode()) {
489       ReplaceNode(ST, OptStore);
490       return;
491     }
492 
493     SDValue Value = ST->getValue();
494     MVT VT = Value.getSimpleValueType();
495     switch (TLI.getOperationAction(ISD::STORE, VT)) {
496     default: llvm_unreachable("This action is not supported yet!");
497     case TargetLowering::Legal: {
498       // If this is an unaligned store and the target doesn't support it,
499       // expand it.
500       EVT MemVT = ST->getMemoryVT();
501       const DataLayout &DL = DAG.getDataLayout();
502       if (!TLI.allowsMemoryAccessForAlignment(*DAG.getContext(), DL, MemVT,
503                                               *ST->getMemOperand())) {
504         LLVM_DEBUG(dbgs() << "Expanding unsupported unaligned store\n");
505         SDValue Result = TLI.expandUnalignedStore(ST, DAG);
506         ReplaceNode(SDValue(ST, 0), Result);
507       } else
508         LLVM_DEBUG(dbgs() << "Legal store\n");
509       break;
510     }
511     case TargetLowering::Custom: {
512       LLVM_DEBUG(dbgs() << "Trying custom lowering\n");
513       SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
514       if (Res && Res != SDValue(Node, 0))
515         ReplaceNode(SDValue(Node, 0), Res);
516       return;
517     }
518     case TargetLowering::Promote: {
519       MVT NVT = TLI.getTypeToPromoteTo(ISD::STORE, VT);
520       assert(NVT.getSizeInBits() == VT.getSizeInBits() &&
521              "Can only promote stores to same size type");
522       Value = DAG.getNode(ISD::BITCAST, dl, NVT, Value);
523       SDValue Result = DAG.getStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
524                                     ST->getOriginalAlign(), MMOFlags, AAInfo);
525       ReplaceNode(SDValue(Node, 0), Result);
526       break;
527     }
528     }
529     return;
530   }
531 
532   LLVM_DEBUG(dbgs() << "Legalizing truncating store operations\n");
533   SDValue Value = ST->getValue();
534   EVT StVT = ST->getMemoryVT();
535   TypeSize StWidth = StVT.getSizeInBits();
536   TypeSize StSize = StVT.getStoreSizeInBits();
537   auto &DL = DAG.getDataLayout();
538 
539   if (StWidth != StSize) {
540     // Promote to a byte-sized store with upper bits zero if not
541     // storing an integral number of bytes.  For example, promote
542     // TRUNCSTORE:i1 X -> TRUNCSTORE:i8 (and X, 1)
543     EVT NVT = EVT::getIntegerVT(*DAG.getContext(), StSize.getFixedValue());
544     Value = DAG.getZeroExtendInReg(Value, dl, StVT);
545     SDValue Result =
546         DAG.getTruncStore(Chain, dl, Value, Ptr, ST->getPointerInfo(), NVT,
547                           ST->getOriginalAlign(), MMOFlags, AAInfo);
548     ReplaceNode(SDValue(Node, 0), Result);
549   } else if (!StVT.isVector() && !isPowerOf2_64(StWidth.getFixedValue())) {
550     // If not storing a power-of-2 number of bits, expand as two stores.
551     assert(!StVT.isVector() && "Unsupported truncstore!");
552     unsigned StWidthBits = StWidth.getFixedValue();
553     unsigned LogStWidth = Log2_32(StWidthBits);
554     assert(LogStWidth < 32);
555     unsigned RoundWidth = 1 << LogStWidth;
556     assert(RoundWidth < StWidthBits);
557     unsigned ExtraWidth = StWidthBits - RoundWidth;
558     assert(ExtraWidth < RoundWidth);
559     assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
560            "Store size not an integral number of bytes!");
561     EVT RoundVT = EVT::getIntegerVT(*DAG.getContext(), RoundWidth);
562     EVT ExtraVT = EVT::getIntegerVT(*DAG.getContext(), ExtraWidth);
563     SDValue Lo, Hi;
564     unsigned IncrementSize;
565 
566     if (DL.isLittleEndian()) {
567       // TRUNCSTORE:i24 X -> TRUNCSTORE:i16 X, TRUNCSTORE@+2:i8 (srl X, 16)
568       // Store the bottom RoundWidth bits.
569       Lo = DAG.getTruncStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
570                              RoundVT, ST->getOriginalAlign(), MMOFlags, AAInfo);
571 
572       // Store the remaining ExtraWidth bits.
573       IncrementSize = RoundWidth / 8;
574       Ptr =
575           DAG.getMemBasePlusOffset(Ptr, TypeSize::getFixed(IncrementSize), dl);
576       Hi = DAG.getNode(
577           ISD::SRL, dl, Value.getValueType(), Value,
578           DAG.getConstant(RoundWidth, dl,
579                           TLI.getShiftAmountTy(Value.getValueType(), DL)));
580       Hi = DAG.getTruncStore(Chain, dl, Hi, Ptr,
581                              ST->getPointerInfo().getWithOffset(IncrementSize),
582                              ExtraVT, ST->getOriginalAlign(), MMOFlags, AAInfo);
583     } else {
584       // Big endian - avoid unaligned stores.
585       // TRUNCSTORE:i24 X -> TRUNCSTORE:i16 (srl X, 8), TRUNCSTORE@+2:i8 X
586       // Store the top RoundWidth bits.
587       Hi = DAG.getNode(
588           ISD::SRL, dl, Value.getValueType(), Value,
589           DAG.getConstant(ExtraWidth, dl,
590                           TLI.getShiftAmountTy(Value.getValueType(), DL)));
591       Hi = DAG.getTruncStore(Chain, dl, Hi, Ptr, ST->getPointerInfo(), RoundVT,
592                              ST->getOriginalAlign(), MMOFlags, AAInfo);
593 
594       // Store the remaining ExtraWidth bits.
595       IncrementSize = RoundWidth / 8;
596       Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
597                         DAG.getConstant(IncrementSize, dl,
598                                         Ptr.getValueType()));
599       Lo = DAG.getTruncStore(Chain, dl, Value, Ptr,
600                              ST->getPointerInfo().getWithOffset(IncrementSize),
601                              ExtraVT, ST->getOriginalAlign(), MMOFlags, AAInfo);
602     }
603 
604     // The order of the stores doesn't matter.
605     SDValue Result = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
606     ReplaceNode(SDValue(Node, 0), Result);
607   } else {
608     switch (TLI.getTruncStoreAction(ST->getValue().getValueType(), StVT)) {
609     default: llvm_unreachable("This action is not supported yet!");
610     case TargetLowering::Legal: {
611       EVT MemVT = ST->getMemoryVT();
612       // If this is an unaligned store and the target doesn't support it,
613       // expand it.
614       if (!TLI.allowsMemoryAccessForAlignment(*DAG.getContext(), DL, MemVT,
615                                               *ST->getMemOperand())) {
616         SDValue Result = TLI.expandUnalignedStore(ST, DAG);
617         ReplaceNode(SDValue(ST, 0), Result);
618       }
619       break;
620     }
621     case TargetLowering::Custom: {
622       SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
623       if (Res && Res != SDValue(Node, 0))
624         ReplaceNode(SDValue(Node, 0), Res);
625       return;
626     }
627     case TargetLowering::Expand:
628       assert(!StVT.isVector() &&
629              "Vector Stores are handled in LegalizeVectorOps");
630 
631       SDValue Result;
632 
633       // TRUNCSTORE:i16 i32 -> STORE i16
634       if (TLI.isTypeLegal(StVT)) {
635         Value = DAG.getNode(ISD::TRUNCATE, dl, StVT, Value);
636         Result = DAG.getStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
637                               ST->getOriginalAlign(), MMOFlags, AAInfo);
638       } else {
639         // The in-memory type isn't legal. Truncate to the type it would promote
640         // to, and then do a truncstore.
641         Value = DAG.getNode(ISD::TRUNCATE, dl,
642                             TLI.getTypeToTransformTo(*DAG.getContext(), StVT),
643                             Value);
644         Result =
645             DAG.getTruncStore(Chain, dl, Value, Ptr, ST->getPointerInfo(), StVT,
646                               ST->getOriginalAlign(), MMOFlags, AAInfo);
647       }
648 
649       ReplaceNode(SDValue(Node, 0), Result);
650       break;
651     }
652   }
653 }
654 
655 void SelectionDAGLegalize::LegalizeLoadOps(SDNode *Node) {
656   LoadSDNode *LD = cast<LoadSDNode>(Node);
657   SDValue Chain = LD->getChain();  // The chain.
658   SDValue Ptr = LD->getBasePtr();  // The base pointer.
659   SDValue Value;                   // The value returned by the load op.
660   SDLoc dl(Node);
661 
662   ISD::LoadExtType ExtType = LD->getExtensionType();
663   if (ExtType == ISD::NON_EXTLOAD) {
664     LLVM_DEBUG(dbgs() << "Legalizing non-extending load operation\n");
665     MVT VT = Node->getSimpleValueType(0);
666     SDValue RVal = SDValue(Node, 0);
667     SDValue RChain = SDValue(Node, 1);
668 
669     switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
670     default: llvm_unreachable("This action is not supported yet!");
671     case TargetLowering::Legal: {
672       EVT MemVT = LD->getMemoryVT();
673       const DataLayout &DL = DAG.getDataLayout();
674       // If this is an unaligned load and the target doesn't support it,
675       // expand it.
676       if (!TLI.allowsMemoryAccessForAlignment(*DAG.getContext(), DL, MemVT,
677                                               *LD->getMemOperand())) {
678         std::tie(RVal, RChain) = TLI.expandUnalignedLoad(LD, DAG);
679       }
680       break;
681     }
682     case TargetLowering::Custom:
683       if (SDValue Res = TLI.LowerOperation(RVal, DAG)) {
684         RVal = Res;
685         RChain = Res.getValue(1);
686       }
687       break;
688 
689     case TargetLowering::Promote: {
690       MVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), VT);
691       assert(NVT.getSizeInBits() == VT.getSizeInBits() &&
692              "Can only promote loads to same size type");
693 
694       SDValue Res = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getMemOperand());
695       RVal = DAG.getNode(ISD::BITCAST, dl, VT, Res);
696       RChain = Res.getValue(1);
697       break;
698     }
699     }
700     if (RChain.getNode() != Node) {
701       assert(RVal.getNode() != Node && "Load must be completely replaced");
702       DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), RVal);
703       DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), RChain);
704       if (UpdatedNodes) {
705         UpdatedNodes->insert(RVal.getNode());
706         UpdatedNodes->insert(RChain.getNode());
707       }
708       ReplacedNode(Node);
709     }
710     return;
711   }
712 
713   LLVM_DEBUG(dbgs() << "Legalizing extending load operation\n");
714   EVT SrcVT = LD->getMemoryVT();
715   TypeSize SrcWidth = SrcVT.getSizeInBits();
716   MachineMemOperand::Flags MMOFlags = LD->getMemOperand()->getFlags();
717   AAMDNodes AAInfo = LD->getAAInfo();
718 
719   if (SrcWidth != SrcVT.getStoreSizeInBits() &&
720       // Some targets pretend to have an i1 loading operation, and actually
721       // load an i8.  This trick is correct for ZEXTLOAD because the top 7
722       // bits are guaranteed to be zero; it helps the optimizers understand
723       // that these bits are zero.  It is also useful for EXTLOAD, since it
724       // tells the optimizers that those bits are undefined.  It would be
725       // nice to have an effective generic way of getting these benefits...
726       // Until such a way is found, don't insist on promoting i1 here.
727       (SrcVT != MVT::i1 ||
728        TLI.getLoadExtAction(ExtType, Node->getValueType(0), MVT::i1) ==
729          TargetLowering::Promote)) {
730     // Promote to a byte-sized load if not loading an integral number of
731     // bytes.  For example, promote EXTLOAD:i20 -> EXTLOAD:i24.
732     unsigned NewWidth = SrcVT.getStoreSizeInBits();
733     EVT NVT = EVT::getIntegerVT(*DAG.getContext(), NewWidth);
734     SDValue Ch;
735 
736     // The extra bits are guaranteed to be zero, since we stored them that
737     // way.  A zext load from NVT thus automatically gives zext from SrcVT.
738 
739     ISD::LoadExtType NewExtType =
740       ExtType == ISD::ZEXTLOAD ? ISD::ZEXTLOAD : ISD::EXTLOAD;
741 
742     SDValue Result = DAG.getExtLoad(NewExtType, dl, Node->getValueType(0),
743                                     Chain, Ptr, LD->getPointerInfo(), NVT,
744                                     LD->getOriginalAlign(), MMOFlags, AAInfo);
745 
746     Ch = Result.getValue(1); // The chain.
747 
748     if (ExtType == ISD::SEXTLOAD)
749       // Having the top bits zero doesn't help when sign extending.
750       Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
751                            Result.getValueType(),
752                            Result, DAG.getValueType(SrcVT));
753     else if (ExtType == ISD::ZEXTLOAD || NVT == Result.getValueType())
754       // All the top bits are guaranteed to be zero - inform the optimizers.
755       Result = DAG.getNode(ISD::AssertZext, dl,
756                            Result.getValueType(), Result,
757                            DAG.getValueType(SrcVT));
758 
759     Value = Result;
760     Chain = Ch;
761   } else if (!isPowerOf2_64(SrcWidth.getKnownMinValue())) {
762     // If not loading a power-of-2 number of bits, expand as two loads.
763     assert(!SrcVT.isVector() && "Unsupported extload!");
764     unsigned SrcWidthBits = SrcWidth.getFixedValue();
765     unsigned LogSrcWidth = Log2_32(SrcWidthBits);
766     assert(LogSrcWidth < 32);
767     unsigned RoundWidth = 1 << LogSrcWidth;
768     assert(RoundWidth < SrcWidthBits);
769     unsigned ExtraWidth = SrcWidthBits - RoundWidth;
770     assert(ExtraWidth < RoundWidth);
771     assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
772            "Load size not an integral number of bytes!");
773     EVT RoundVT = EVT::getIntegerVT(*DAG.getContext(), RoundWidth);
774     EVT ExtraVT = EVT::getIntegerVT(*DAG.getContext(), ExtraWidth);
775     SDValue Lo, Hi, Ch;
776     unsigned IncrementSize;
777     auto &DL = DAG.getDataLayout();
778 
779     if (DL.isLittleEndian()) {
780       // EXTLOAD:i24 -> ZEXTLOAD:i16 | (shl EXTLOAD@+2:i8, 16)
781       // Load the bottom RoundWidth bits.
782       Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, Node->getValueType(0), Chain, Ptr,
783                           LD->getPointerInfo(), RoundVT, LD->getOriginalAlign(),
784                           MMOFlags, AAInfo);
785 
786       // Load the remaining ExtraWidth bits.
787       IncrementSize = RoundWidth / 8;
788       Ptr =
789           DAG.getMemBasePlusOffset(Ptr, TypeSize::getFixed(IncrementSize), dl);
790       Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Chain, Ptr,
791                           LD->getPointerInfo().getWithOffset(IncrementSize),
792                           ExtraVT, LD->getOriginalAlign(), MMOFlags, AAInfo);
793 
794       // Build a factor node to remember that this load is independent of
795       // the other one.
796       Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
797                        Hi.getValue(1));
798 
799       // Move the top bits to the right place.
800       Hi = DAG.getNode(
801           ISD::SHL, dl, Hi.getValueType(), Hi,
802           DAG.getConstant(RoundWidth, dl,
803                           TLI.getShiftAmountTy(Hi.getValueType(), DL)));
804 
805       // Join the hi and lo parts.
806       Value = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
807     } else {
808       // Big endian - avoid unaligned loads.
809       // EXTLOAD:i24 -> (shl EXTLOAD:i16, 8) | ZEXTLOAD@+2:i8
810       // Load the top RoundWidth bits.
811       Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Chain, Ptr,
812                           LD->getPointerInfo(), RoundVT, LD->getOriginalAlign(),
813                           MMOFlags, AAInfo);
814 
815       // Load the remaining ExtraWidth bits.
816       IncrementSize = RoundWidth / 8;
817       Ptr =
818           DAG.getMemBasePlusOffset(Ptr, TypeSize::getFixed(IncrementSize), dl);
819       Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, Node->getValueType(0), Chain, Ptr,
820                           LD->getPointerInfo().getWithOffset(IncrementSize),
821                           ExtraVT, LD->getOriginalAlign(), MMOFlags, AAInfo);
822 
823       // Build a factor node to remember that this load is independent of
824       // the other one.
825       Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
826                        Hi.getValue(1));
827 
828       // Move the top bits to the right place.
829       Hi = DAG.getNode(
830           ISD::SHL, dl, Hi.getValueType(), Hi,
831           DAG.getConstant(ExtraWidth, dl,
832                           TLI.getShiftAmountTy(Hi.getValueType(), DL)));
833 
834       // Join the hi and lo parts.
835       Value = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
836     }
837 
838     Chain = Ch;
839   } else {
840     bool isCustom = false;
841     switch (TLI.getLoadExtAction(ExtType, Node->getValueType(0),
842                                  SrcVT.getSimpleVT())) {
843     default: llvm_unreachable("This action is not supported yet!");
844     case TargetLowering::Custom:
845       isCustom = true;
846       [[fallthrough]];
847     case TargetLowering::Legal:
848       Value = SDValue(Node, 0);
849       Chain = SDValue(Node, 1);
850 
851       if (isCustom) {
852         if (SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG)) {
853           Value = Res;
854           Chain = Res.getValue(1);
855         }
856       } else {
857         // If this is an unaligned load and the target doesn't support it,
858         // expand it.
859         EVT MemVT = LD->getMemoryVT();
860         const DataLayout &DL = DAG.getDataLayout();
861         if (!TLI.allowsMemoryAccess(*DAG.getContext(), DL, MemVT,
862                                     *LD->getMemOperand())) {
863           std::tie(Value, Chain) = TLI.expandUnalignedLoad(LD, DAG);
864         }
865       }
866       break;
867 
868     case TargetLowering::Expand: {
869       EVT DestVT = Node->getValueType(0);
870       if (!TLI.isLoadExtLegal(ISD::EXTLOAD, DestVT, SrcVT)) {
871         // If the source type is not legal, see if there is a legal extload to
872         // an intermediate type that we can then extend further.
873         EVT LoadVT = TLI.getRegisterType(SrcVT.getSimpleVT());
874         if ((LoadVT.isFloatingPoint() == SrcVT.isFloatingPoint()) &&
875             (TLI.isTypeLegal(SrcVT) || // Same as SrcVT == LoadVT?
876              TLI.isLoadExtLegal(ExtType, LoadVT, SrcVT))) {
877           // If we are loading a legal type, this is a non-extload followed by a
878           // full extend.
879           ISD::LoadExtType MidExtType =
880               (LoadVT == SrcVT) ? ISD::NON_EXTLOAD : ExtType;
881 
882           SDValue Load = DAG.getExtLoad(MidExtType, dl, LoadVT, Chain, Ptr,
883                                         SrcVT, LD->getMemOperand());
884           unsigned ExtendOp =
885               ISD::getExtForLoadExtType(SrcVT.isFloatingPoint(), ExtType);
886           Value = DAG.getNode(ExtendOp, dl, Node->getValueType(0), Load);
887           Chain = Load.getValue(1);
888           break;
889         }
890 
891         // Handle the special case of fp16 extloads. EXTLOAD doesn't have the
892         // normal undefined upper bits behavior to allow using an in-reg extend
893         // with the illegal FP type, so load as an integer and do the
894         // from-integer conversion.
895         EVT SVT = SrcVT.getScalarType();
896         if (SVT == MVT::f16 || SVT == MVT::bf16) {
897           EVT ISrcVT = SrcVT.changeTypeToInteger();
898           EVT IDestVT = DestVT.changeTypeToInteger();
899           EVT ILoadVT = TLI.getRegisterType(IDestVT.getSimpleVT());
900 
901           SDValue Result = DAG.getExtLoad(ISD::ZEXTLOAD, dl, ILoadVT, Chain,
902                                           Ptr, ISrcVT, LD->getMemOperand());
903           Value =
904               DAG.getNode(SVT == MVT::f16 ? ISD::FP16_TO_FP : ISD::BF16_TO_FP,
905                           dl, DestVT, Result);
906           Chain = Result.getValue(1);
907           break;
908         }
909       }
910 
911       assert(!SrcVT.isVector() &&
912              "Vector Loads are handled in LegalizeVectorOps");
913 
914       // FIXME: This does not work for vectors on most targets.  Sign-
915       // and zero-extend operations are currently folded into extending
916       // loads, whether they are legal or not, and then we end up here
917       // without any support for legalizing them.
918       assert(ExtType != ISD::EXTLOAD &&
919              "EXTLOAD should always be supported!");
920       // Turn the unsupported load into an EXTLOAD followed by an
921       // explicit zero/sign extend inreg.
922       SDValue Result = DAG.getExtLoad(ISD::EXTLOAD, dl,
923                                       Node->getValueType(0),
924                                       Chain, Ptr, SrcVT,
925                                       LD->getMemOperand());
926       SDValue ValRes;
927       if (ExtType == ISD::SEXTLOAD)
928         ValRes = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
929                              Result.getValueType(),
930                              Result, DAG.getValueType(SrcVT));
931       else
932         ValRes = DAG.getZeroExtendInReg(Result, dl, SrcVT);
933       Value = ValRes;
934       Chain = Result.getValue(1);
935       break;
936     }
937     }
938   }
939 
940   // Since loads produce two values, make sure to remember that we legalized
941   // both of them.
942   if (Chain.getNode() != Node) {
943     assert(Value.getNode() != Node && "Load must be completely replaced");
944     DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), Value);
945     DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), Chain);
946     if (UpdatedNodes) {
947       UpdatedNodes->insert(Value.getNode());
948       UpdatedNodes->insert(Chain.getNode());
949     }
950     ReplacedNode(Node);
951   }
952 }
953 
954 /// Return a legal replacement for the given operation, with all legal operands.
955 void SelectionDAGLegalize::LegalizeOp(SDNode *Node) {
956   LLVM_DEBUG(dbgs() << "\nLegalizing: "; Node->dump(&DAG));
957 
958   // Allow illegal target nodes and illegal registers.
959   if (Node->getOpcode() == ISD::TargetConstant ||
960       Node->getOpcode() == ISD::Register)
961     return;
962 
963 #ifndef NDEBUG
964   for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
965     assert(TLI.getTypeAction(*DAG.getContext(), Node->getValueType(i)) ==
966              TargetLowering::TypeLegal &&
967            "Unexpected illegal type!");
968 
969   for (const SDValue &Op : Node->op_values())
970     assert((TLI.getTypeAction(*DAG.getContext(), Op.getValueType()) ==
971               TargetLowering::TypeLegal ||
972             Op.getOpcode() == ISD::TargetConstant ||
973             Op.getOpcode() == ISD::Register) &&
974             "Unexpected illegal type!");
975 #endif
976 
977   // Figure out the correct action; the way to query this varies by opcode
978   TargetLowering::LegalizeAction Action = TargetLowering::Legal;
979   bool SimpleFinishLegalizing = true;
980   switch (Node->getOpcode()) {
981   case ISD::INTRINSIC_W_CHAIN:
982   case ISD::INTRINSIC_WO_CHAIN:
983   case ISD::INTRINSIC_VOID:
984   case ISD::STACKSAVE:
985     Action = TLI.getOperationAction(Node->getOpcode(), MVT::Other);
986     break;
987   case ISD::GET_DYNAMIC_AREA_OFFSET:
988     Action = TLI.getOperationAction(Node->getOpcode(),
989                                     Node->getValueType(0));
990     break;
991   case ISD::VAARG:
992     Action = TLI.getOperationAction(Node->getOpcode(),
993                                     Node->getValueType(0));
994     if (Action != TargetLowering::Promote)
995       Action = TLI.getOperationAction(Node->getOpcode(), MVT::Other);
996     break;
997   case ISD::SET_FPENV:
998   case ISD::SET_FPMODE:
999     Action = TLI.getOperationAction(Node->getOpcode(),
1000                                     Node->getOperand(1).getValueType());
1001     break;
1002   case ISD::FP_TO_FP16:
1003   case ISD::FP_TO_BF16:
1004   case ISD::SINT_TO_FP:
1005   case ISD::UINT_TO_FP:
1006   case ISD::EXTRACT_VECTOR_ELT:
1007   case ISD::LROUND:
1008   case ISD::LLROUND:
1009   case ISD::LRINT:
1010   case ISD::LLRINT:
1011     Action = TLI.getOperationAction(Node->getOpcode(),
1012                                     Node->getOperand(0).getValueType());
1013     break;
1014   case ISD::STRICT_FP_TO_FP16:
1015   case ISD::STRICT_FP_TO_BF16:
1016   case ISD::STRICT_SINT_TO_FP:
1017   case ISD::STRICT_UINT_TO_FP:
1018   case ISD::STRICT_LRINT:
1019   case ISD::STRICT_LLRINT:
1020   case ISD::STRICT_LROUND:
1021   case ISD::STRICT_LLROUND:
1022     // These pseudo-ops are the same as the other STRICT_ ops except
1023     // they are registered with setOperationAction() using the input type
1024     // instead of the output type.
1025     Action = TLI.getOperationAction(Node->getOpcode(),
1026                                     Node->getOperand(1).getValueType());
1027     break;
1028   case ISD::SIGN_EXTEND_INREG: {
1029     EVT InnerType = cast<VTSDNode>(Node->getOperand(1))->getVT();
1030     Action = TLI.getOperationAction(Node->getOpcode(), InnerType);
1031     break;
1032   }
1033   case ISD::ATOMIC_STORE:
1034     Action = TLI.getOperationAction(Node->getOpcode(),
1035                                     Node->getOperand(1).getValueType());
1036     break;
1037   case ISD::SELECT_CC:
1038   case ISD::STRICT_FSETCC:
1039   case ISD::STRICT_FSETCCS:
1040   case ISD::SETCC:
1041   case ISD::SETCCCARRY:
1042   case ISD::VP_SETCC:
1043   case ISD::BR_CC: {
1044     unsigned Opc = Node->getOpcode();
1045     unsigned CCOperand = Opc == ISD::SELECT_CC                         ? 4
1046                          : Opc == ISD::STRICT_FSETCC                   ? 3
1047                          : Opc == ISD::STRICT_FSETCCS                  ? 3
1048                          : Opc == ISD::SETCCCARRY                      ? 3
1049                          : (Opc == ISD::SETCC || Opc == ISD::VP_SETCC) ? 2
1050                                                                        : 1;
1051     unsigned CompareOperand = Opc == ISD::BR_CC            ? 2
1052                               : Opc == ISD::STRICT_FSETCC  ? 1
1053                               : Opc == ISD::STRICT_FSETCCS ? 1
1054                                                            : 0;
1055     MVT OpVT = Node->getOperand(CompareOperand).getSimpleValueType();
1056     ISD::CondCode CCCode =
1057         cast<CondCodeSDNode>(Node->getOperand(CCOperand))->get();
1058     Action = TLI.getCondCodeAction(CCCode, OpVT);
1059     if (Action == TargetLowering::Legal) {
1060       if (Node->getOpcode() == ISD::SELECT_CC)
1061         Action = TLI.getOperationAction(Node->getOpcode(),
1062                                         Node->getValueType(0));
1063       else
1064         Action = TLI.getOperationAction(Node->getOpcode(), OpVT);
1065     }
1066     break;
1067   }
1068   case ISD::LOAD:
1069   case ISD::STORE:
1070     // FIXME: Model these properly.  LOAD and STORE are complicated, and
1071     // STORE expects the unlegalized operand in some cases.
1072     SimpleFinishLegalizing = false;
1073     break;
1074   case ISD::CALLSEQ_START:
1075   case ISD::CALLSEQ_END:
1076     // FIXME: This shouldn't be necessary.  These nodes have special properties
1077     // dealing with the recursive nature of legalization.  Removing this
1078     // special case should be done as part of making LegalizeDAG non-recursive.
1079     SimpleFinishLegalizing = false;
1080     break;
1081   case ISD::EXTRACT_ELEMENT:
1082   case ISD::GET_ROUNDING:
1083   case ISD::MERGE_VALUES:
1084   case ISD::EH_RETURN:
1085   case ISD::FRAME_TO_ARGS_OFFSET:
1086   case ISD::EH_DWARF_CFA:
1087   case ISD::EH_SJLJ_SETJMP:
1088   case ISD::EH_SJLJ_LONGJMP:
1089   case ISD::EH_SJLJ_SETUP_DISPATCH:
1090     // These operations lie about being legal: when they claim to be legal,
1091     // they should actually be expanded.
1092     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1093     if (Action == TargetLowering::Legal)
1094       Action = TargetLowering::Expand;
1095     break;
1096   case ISD::INIT_TRAMPOLINE:
1097   case ISD::ADJUST_TRAMPOLINE:
1098   case ISD::FRAMEADDR:
1099   case ISD::RETURNADDR:
1100   case ISD::ADDROFRETURNADDR:
1101   case ISD::SPONENTRY:
1102     // These operations lie about being legal: when they claim to be legal,
1103     // they should actually be custom-lowered.
1104     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1105     if (Action == TargetLowering::Legal)
1106       Action = TargetLowering::Custom;
1107     break;
1108   case ISD::CLEAR_CACHE:
1109     // This operation is typically going to be LibCall unless the target wants
1110     // something differrent.
1111     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1112     break;
1113   case ISD::READCYCLECOUNTER:
1114   case ISD::READSTEADYCOUNTER:
1115     // READCYCLECOUNTER and READSTEADYCOUNTER return a i64, even if type
1116     // legalization might have expanded that to several smaller types.
1117     Action = TLI.getOperationAction(Node->getOpcode(), MVT::i64);
1118     break;
1119   case ISD::READ_REGISTER:
1120   case ISD::WRITE_REGISTER:
1121     // Named register is legal in the DAG, but blocked by register name
1122     // selection if not implemented by target (to chose the correct register)
1123     // They'll be converted to Copy(To/From)Reg.
1124     Action = TargetLowering::Legal;
1125     break;
1126   case ISD::UBSANTRAP:
1127     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1128     if (Action == TargetLowering::Expand) {
1129       // replace ISD::UBSANTRAP with ISD::TRAP
1130       SDValue NewVal;
1131       NewVal = DAG.getNode(ISD::TRAP, SDLoc(Node), Node->getVTList(),
1132                            Node->getOperand(0));
1133       ReplaceNode(Node, NewVal.getNode());
1134       LegalizeOp(NewVal.getNode());
1135       return;
1136     }
1137     break;
1138   case ISD::DEBUGTRAP:
1139     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1140     if (Action == TargetLowering::Expand) {
1141       // replace ISD::DEBUGTRAP with ISD::TRAP
1142       SDValue NewVal;
1143       NewVal = DAG.getNode(ISD::TRAP, SDLoc(Node), Node->getVTList(),
1144                            Node->getOperand(0));
1145       ReplaceNode(Node, NewVal.getNode());
1146       LegalizeOp(NewVal.getNode());
1147       return;
1148     }
1149     break;
1150   case ISD::SADDSAT:
1151   case ISD::UADDSAT:
1152   case ISD::SSUBSAT:
1153   case ISD::USUBSAT:
1154   case ISD::SSHLSAT:
1155   case ISD::USHLSAT:
1156   case ISD::SCMP:
1157   case ISD::UCMP:
1158   case ISD::FP_TO_SINT_SAT:
1159   case ISD::FP_TO_UINT_SAT:
1160     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1161     break;
1162   case ISD::SMULFIX:
1163   case ISD::SMULFIXSAT:
1164   case ISD::UMULFIX:
1165   case ISD::UMULFIXSAT:
1166   case ISD::SDIVFIX:
1167   case ISD::SDIVFIXSAT:
1168   case ISD::UDIVFIX:
1169   case ISD::UDIVFIXSAT: {
1170     unsigned Scale = Node->getConstantOperandVal(2);
1171     Action = TLI.getFixedPointOperationAction(Node->getOpcode(),
1172                                               Node->getValueType(0), Scale);
1173     break;
1174   }
1175   case ISD::MSCATTER:
1176     Action = TLI.getOperationAction(Node->getOpcode(),
1177                     cast<MaskedScatterSDNode>(Node)->getValue().getValueType());
1178     break;
1179   case ISD::MSTORE:
1180     Action = TLI.getOperationAction(Node->getOpcode(),
1181                     cast<MaskedStoreSDNode>(Node)->getValue().getValueType());
1182     break;
1183   case ISD::VP_SCATTER:
1184     Action = TLI.getOperationAction(
1185         Node->getOpcode(),
1186         cast<VPScatterSDNode>(Node)->getValue().getValueType());
1187     break;
1188   case ISD::VP_STORE:
1189     Action = TLI.getOperationAction(
1190         Node->getOpcode(),
1191         cast<VPStoreSDNode>(Node)->getValue().getValueType());
1192     break;
1193   case ISD::EXPERIMENTAL_VP_STRIDED_STORE:
1194     Action = TLI.getOperationAction(
1195         Node->getOpcode(),
1196         cast<VPStridedStoreSDNode>(Node)->getValue().getValueType());
1197     break;
1198   case ISD::VECREDUCE_FADD:
1199   case ISD::VECREDUCE_FMUL:
1200   case ISD::VECREDUCE_ADD:
1201   case ISD::VECREDUCE_MUL:
1202   case ISD::VECREDUCE_AND:
1203   case ISD::VECREDUCE_OR:
1204   case ISD::VECREDUCE_XOR:
1205   case ISD::VECREDUCE_SMAX:
1206   case ISD::VECREDUCE_SMIN:
1207   case ISD::VECREDUCE_UMAX:
1208   case ISD::VECREDUCE_UMIN:
1209   case ISD::VECREDUCE_FMAX:
1210   case ISD::VECREDUCE_FMIN:
1211   case ISD::VECREDUCE_FMAXIMUM:
1212   case ISD::VECREDUCE_FMINIMUM:
1213   case ISD::IS_FPCLASS:
1214     Action = TLI.getOperationAction(
1215         Node->getOpcode(), Node->getOperand(0).getValueType());
1216     break;
1217   case ISD::VECREDUCE_SEQ_FADD:
1218   case ISD::VECREDUCE_SEQ_FMUL:
1219   case ISD::VP_REDUCE_FADD:
1220   case ISD::VP_REDUCE_FMUL:
1221   case ISD::VP_REDUCE_ADD:
1222   case ISD::VP_REDUCE_MUL:
1223   case ISD::VP_REDUCE_AND:
1224   case ISD::VP_REDUCE_OR:
1225   case ISD::VP_REDUCE_XOR:
1226   case ISD::VP_REDUCE_SMAX:
1227   case ISD::VP_REDUCE_SMIN:
1228   case ISD::VP_REDUCE_UMAX:
1229   case ISD::VP_REDUCE_UMIN:
1230   case ISD::VP_REDUCE_FMAX:
1231   case ISD::VP_REDUCE_FMIN:
1232   case ISD::VP_REDUCE_FMAXIMUM:
1233   case ISD::VP_REDUCE_FMINIMUM:
1234   case ISD::VP_REDUCE_SEQ_FADD:
1235   case ISD::VP_REDUCE_SEQ_FMUL:
1236     Action = TLI.getOperationAction(
1237         Node->getOpcode(), Node->getOperand(1).getValueType());
1238     break;
1239   case ISD::VP_CTTZ_ELTS:
1240   case ISD::VP_CTTZ_ELTS_ZERO_UNDEF:
1241     Action = TLI.getOperationAction(Node->getOpcode(),
1242                                     Node->getOperand(0).getValueType());
1243     break;
1244   default:
1245     if (Node->getOpcode() >= ISD::BUILTIN_OP_END) {
1246       Action = TLI.getCustomOperationAction(*Node);
1247     } else {
1248       Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1249     }
1250     break;
1251   }
1252 
1253   if (SimpleFinishLegalizing) {
1254     SDNode *NewNode = Node;
1255     switch (Node->getOpcode()) {
1256     default: break;
1257     case ISD::SHL:
1258     case ISD::SRL:
1259     case ISD::SRA:
1260     case ISD::ROTL:
1261     case ISD::ROTR: {
1262       // Legalizing shifts/rotates requires adjusting the shift amount
1263       // to the appropriate width.
1264       SDValue Op0 = Node->getOperand(0);
1265       SDValue Op1 = Node->getOperand(1);
1266       if (!Op1.getValueType().isVector()) {
1267         SDValue SAO = DAG.getShiftAmountOperand(Op0.getValueType(), Op1);
1268         // The getShiftAmountOperand() may create a new operand node or
1269         // return the existing one. If new operand is created we need
1270         // to update the parent node.
1271         // Do not try to legalize SAO here! It will be automatically legalized
1272         // in the next round.
1273         if (SAO != Op1)
1274           NewNode = DAG.UpdateNodeOperands(Node, Op0, SAO);
1275       }
1276     }
1277     break;
1278     case ISD::FSHL:
1279     case ISD::FSHR:
1280     case ISD::SRL_PARTS:
1281     case ISD::SRA_PARTS:
1282     case ISD::SHL_PARTS: {
1283       // Legalizing shifts/rotates requires adjusting the shift amount
1284       // to the appropriate width.
1285       SDValue Op0 = Node->getOperand(0);
1286       SDValue Op1 = Node->getOperand(1);
1287       SDValue Op2 = Node->getOperand(2);
1288       if (!Op2.getValueType().isVector()) {
1289         SDValue SAO = DAG.getShiftAmountOperand(Op0.getValueType(), Op2);
1290         // The getShiftAmountOperand() may create a new operand node or
1291         // return the existing one. If new operand is created we need
1292         // to update the parent node.
1293         if (SAO != Op2)
1294           NewNode = DAG.UpdateNodeOperands(Node, Op0, Op1, SAO);
1295       }
1296       break;
1297     }
1298     }
1299 
1300     if (NewNode != Node) {
1301       ReplaceNode(Node, NewNode);
1302       Node = NewNode;
1303     }
1304     switch (Action) {
1305     case TargetLowering::Legal:
1306       LLVM_DEBUG(dbgs() << "Legal node: nothing to do\n");
1307       return;
1308     case TargetLowering::Custom:
1309       LLVM_DEBUG(dbgs() << "Trying custom legalization\n");
1310       // FIXME: The handling for custom lowering with multiple results is
1311       // a complete mess.
1312       if (SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG)) {
1313         if (!(Res.getNode() != Node || Res.getResNo() != 0))
1314           return;
1315 
1316         if (Node->getNumValues() == 1) {
1317           // Verify the new types match the original. Glue is waived because
1318           // ISD::ADDC can be legalized by replacing Glue with an integer type.
1319           assert((Res.getValueType() == Node->getValueType(0) ||
1320                   Node->getValueType(0) == MVT::Glue) &&
1321                  "Type mismatch for custom legalized operation");
1322           LLVM_DEBUG(dbgs() << "Successfully custom legalized node\n");
1323           // We can just directly replace this node with the lowered value.
1324           ReplaceNode(SDValue(Node, 0), Res);
1325           return;
1326         }
1327 
1328         SmallVector<SDValue, 8> ResultVals;
1329         for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i) {
1330           // Verify the new types match the original. Glue is waived because
1331           // ISD::ADDC can be legalized by replacing Glue with an integer type.
1332           assert((Res->getValueType(i) == Node->getValueType(i) ||
1333                   Node->getValueType(i) == MVT::Glue) &&
1334                  "Type mismatch for custom legalized operation");
1335           ResultVals.push_back(Res.getValue(i));
1336         }
1337         LLVM_DEBUG(dbgs() << "Successfully custom legalized node\n");
1338         ReplaceNode(Node, ResultVals.data());
1339         return;
1340       }
1341       LLVM_DEBUG(dbgs() << "Could not custom legalize node\n");
1342       [[fallthrough]];
1343     case TargetLowering::Expand:
1344       if (ExpandNode(Node))
1345         return;
1346       [[fallthrough]];
1347     case TargetLowering::LibCall:
1348       ConvertNodeToLibcall(Node);
1349       return;
1350     case TargetLowering::Promote:
1351       PromoteNode(Node);
1352       return;
1353     }
1354   }
1355 
1356   switch (Node->getOpcode()) {
1357   default:
1358 #ifndef NDEBUG
1359     dbgs() << "NODE: ";
1360     Node->dump( &DAG);
1361     dbgs() << "\n";
1362 #endif
1363     llvm_unreachable("Do not know how to legalize this operator!");
1364 
1365   case ISD::CALLSEQ_START:
1366   case ISD::CALLSEQ_END:
1367     break;
1368   case ISD::LOAD:
1369     return LegalizeLoadOps(Node);
1370   case ISD::STORE:
1371     return LegalizeStoreOps(Node);
1372   }
1373 }
1374 
1375 SDValue SelectionDAGLegalize::ExpandExtractFromVectorThroughStack(SDValue Op) {
1376   SDValue Vec = Op.getOperand(0);
1377   SDValue Idx = Op.getOperand(1);
1378   SDLoc dl(Op);
1379 
1380   // Before we generate a new store to a temporary stack slot, see if there is
1381   // already one that we can use. There often is because when we scalarize
1382   // vector operations (using SelectionDAG::UnrollVectorOp for example) a whole
1383   // series of EXTRACT_VECTOR_ELT nodes are generated, one for each element in
1384   // the vector. If all are expanded here, we don't want one store per vector
1385   // element.
1386 
1387   // Caches for hasPredecessorHelper
1388   SmallPtrSet<const SDNode *, 32> Visited;
1389   SmallVector<const SDNode *, 16> Worklist;
1390   Visited.insert(Op.getNode());
1391   Worklist.push_back(Idx.getNode());
1392   SDValue StackPtr, Ch;
1393   for (SDNode *User : Vec.getNode()->uses()) {
1394     if (StoreSDNode *ST = dyn_cast<StoreSDNode>(User)) {
1395       if (ST->isIndexed() || ST->isTruncatingStore() ||
1396           ST->getValue() != Vec)
1397         continue;
1398 
1399       // Make sure that nothing else could have stored into the destination of
1400       // this store.
1401       if (!ST->getChain().reachesChainWithoutSideEffects(DAG.getEntryNode()))
1402         continue;
1403 
1404       // If the index is dependent on the store we will introduce a cycle when
1405       // creating the load (the load uses the index, and by replacing the chain
1406       // we will make the index dependent on the load). Also, the store might be
1407       // dependent on the extractelement and introduce a cycle when creating
1408       // the load.
1409       if (SDNode::hasPredecessorHelper(ST, Visited, Worklist) ||
1410           ST->hasPredecessor(Op.getNode()))
1411         continue;
1412 
1413       StackPtr = ST->getBasePtr();
1414       Ch = SDValue(ST, 0);
1415       break;
1416     }
1417   }
1418 
1419   EVT VecVT = Vec.getValueType();
1420 
1421   if (!Ch.getNode()) {
1422     // Store the value to a temporary stack slot, then LOAD the returned part.
1423     StackPtr = DAG.CreateStackTemporary(VecVT);
1424     MachineMemOperand *StoreMMO = getStackAlignedMMO(
1425         StackPtr, DAG.getMachineFunction(), VecVT.isScalableVector());
1426     Ch = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr, StoreMMO);
1427   }
1428 
1429   SDValue NewLoad;
1430   Align ElementAlignment =
1431       std::min(cast<StoreSDNode>(Ch)->getAlign(),
1432                DAG.getDataLayout().getPrefTypeAlign(
1433                    Op.getValueType().getTypeForEVT(*DAG.getContext())));
1434 
1435   if (Op.getValueType().isVector()) {
1436     StackPtr = TLI.getVectorSubVecPointer(DAG, StackPtr, VecVT,
1437                                           Op.getValueType(), Idx);
1438     NewLoad = DAG.getLoad(Op.getValueType(), dl, Ch, StackPtr,
1439                           MachinePointerInfo(), ElementAlignment);
1440   } else {
1441     StackPtr = TLI.getVectorElementPointer(DAG, StackPtr, VecVT, Idx);
1442     NewLoad = DAG.getExtLoad(ISD::EXTLOAD, dl, Op.getValueType(), Ch, StackPtr,
1443                              MachinePointerInfo(), VecVT.getVectorElementType(),
1444                              ElementAlignment);
1445   }
1446 
1447   // Replace the chain going out of the store, by the one out of the load.
1448   DAG.ReplaceAllUsesOfValueWith(Ch, SDValue(NewLoad.getNode(), 1));
1449 
1450   // We introduced a cycle though, so update the loads operands, making sure
1451   // to use the original store's chain as an incoming chain.
1452   SmallVector<SDValue, 6> NewLoadOperands(NewLoad->op_begin(),
1453                                           NewLoad->op_end());
1454   NewLoadOperands[0] = Ch;
1455   NewLoad =
1456       SDValue(DAG.UpdateNodeOperands(NewLoad.getNode(), NewLoadOperands), 0);
1457   return NewLoad;
1458 }
1459 
1460 SDValue SelectionDAGLegalize::ExpandInsertToVectorThroughStack(SDValue Op) {
1461   assert(Op.getValueType().isVector() && "Non-vector insert subvector!");
1462 
1463   SDValue Vec  = Op.getOperand(0);
1464   SDValue Part = Op.getOperand(1);
1465   SDValue Idx  = Op.getOperand(2);
1466   SDLoc dl(Op);
1467 
1468   // Store the value to a temporary stack slot, then LOAD the returned part.
1469   EVT VecVT = Vec.getValueType();
1470   EVT PartVT = Part.getValueType();
1471   SDValue StackPtr = DAG.CreateStackTemporary(VecVT);
1472   int FI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
1473   MachinePointerInfo PtrInfo =
1474       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI);
1475 
1476   // First store the whole vector.
1477   SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr, PtrInfo);
1478 
1479   // Freeze the index so we don't poison the clamping code we're about to emit.
1480   Idx = DAG.getFreeze(Idx);
1481 
1482   // Then store the inserted part.
1483   if (PartVT.isVector()) {
1484     SDValue SubStackPtr =
1485         TLI.getVectorSubVecPointer(DAG, StackPtr, VecVT, PartVT, Idx);
1486 
1487     // Store the subvector.
1488     Ch = DAG.getStore(
1489         Ch, dl, Part, SubStackPtr,
1490         MachinePointerInfo::getUnknownStack(DAG.getMachineFunction()));
1491   } else {
1492     SDValue SubStackPtr =
1493         TLI.getVectorElementPointer(DAG, StackPtr, VecVT, Idx);
1494 
1495     // Store the scalar value.
1496     Ch = DAG.getTruncStore(
1497         Ch, dl, Part, SubStackPtr,
1498         MachinePointerInfo::getUnknownStack(DAG.getMachineFunction()),
1499         VecVT.getVectorElementType());
1500   }
1501 
1502   // Finally, load the updated vector.
1503   return DAG.getLoad(Op.getValueType(), dl, Ch, StackPtr, PtrInfo);
1504 }
1505 
1506 SDValue SelectionDAGLegalize::ExpandVectorBuildThroughStack(SDNode* Node) {
1507   assert((Node->getOpcode() == ISD::BUILD_VECTOR ||
1508           Node->getOpcode() == ISD::CONCAT_VECTORS) &&
1509          "Unexpected opcode!");
1510 
1511   // We can't handle this case efficiently.  Allocate a sufficiently
1512   // aligned object on the stack, store each operand into it, then load
1513   // the result as a vector.
1514   // Create the stack frame object.
1515   EVT VT = Node->getValueType(0);
1516   EVT MemVT = isa<BuildVectorSDNode>(Node) ? VT.getVectorElementType()
1517                                            : Node->getOperand(0).getValueType();
1518   SDLoc dl(Node);
1519   SDValue FIPtr = DAG.CreateStackTemporary(VT);
1520   int FI = cast<FrameIndexSDNode>(FIPtr.getNode())->getIndex();
1521   MachinePointerInfo PtrInfo =
1522       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI);
1523 
1524   // Emit a store of each element to the stack slot.
1525   SmallVector<SDValue, 8> Stores;
1526   unsigned TypeByteSize = MemVT.getSizeInBits() / 8;
1527   assert(TypeByteSize > 0 && "Vector element type too small for stack store!");
1528 
1529   // If the destination vector element type of a BUILD_VECTOR is narrower than
1530   // the source element type, only store the bits necessary.
1531   bool Truncate = isa<BuildVectorSDNode>(Node) &&
1532                   MemVT.bitsLT(Node->getOperand(0).getValueType());
1533 
1534   // Store (in the right endianness) the elements to memory.
1535   for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
1536     // Ignore undef elements.
1537     if (Node->getOperand(i).isUndef()) continue;
1538 
1539     unsigned Offset = TypeByteSize*i;
1540 
1541     SDValue Idx =
1542         DAG.getMemBasePlusOffset(FIPtr, TypeSize::getFixed(Offset), dl);
1543 
1544     if (Truncate)
1545       Stores.push_back(DAG.getTruncStore(DAG.getEntryNode(), dl,
1546                                          Node->getOperand(i), Idx,
1547                                          PtrInfo.getWithOffset(Offset), MemVT));
1548     else
1549       Stores.push_back(DAG.getStore(DAG.getEntryNode(), dl, Node->getOperand(i),
1550                                     Idx, PtrInfo.getWithOffset(Offset)));
1551   }
1552 
1553   SDValue StoreChain;
1554   if (!Stores.empty())    // Not all undef elements?
1555     StoreChain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Stores);
1556   else
1557     StoreChain = DAG.getEntryNode();
1558 
1559   // Result is a load from the stack slot.
1560   return DAG.getLoad(VT, dl, StoreChain, FIPtr, PtrInfo);
1561 }
1562 
1563 /// Bitcast a floating-point value to an integer value. Only bitcast the part
1564 /// containing the sign bit if the target has no integer value capable of
1565 /// holding all bits of the floating-point value.
1566 void SelectionDAGLegalize::getSignAsIntValue(FloatSignAsInt &State,
1567                                              const SDLoc &DL,
1568                                              SDValue Value) const {
1569   EVT FloatVT = Value.getValueType();
1570   unsigned NumBits = FloatVT.getScalarSizeInBits();
1571   State.FloatVT = FloatVT;
1572   EVT IVT = EVT::getIntegerVT(*DAG.getContext(), NumBits);
1573   // Convert to an integer of the same size.
1574   if (TLI.isTypeLegal(IVT)) {
1575     State.IntValue = DAG.getNode(ISD::BITCAST, DL, IVT, Value);
1576     State.SignMask = APInt::getSignMask(NumBits);
1577     State.SignBit = NumBits - 1;
1578     return;
1579   }
1580 
1581   auto &DataLayout = DAG.getDataLayout();
1582   // Store the float to memory, then load the sign part out as an integer.
1583   MVT LoadTy = TLI.getRegisterType(MVT::i8);
1584   // First create a temporary that is aligned for both the load and store.
1585   SDValue StackPtr = DAG.CreateStackTemporary(FloatVT, LoadTy);
1586   int FI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
1587   // Then store the float to it.
1588   State.FloatPtr = StackPtr;
1589   MachineFunction &MF = DAG.getMachineFunction();
1590   State.FloatPointerInfo = MachinePointerInfo::getFixedStack(MF, FI);
1591   State.Chain = DAG.getStore(DAG.getEntryNode(), DL, Value, State.FloatPtr,
1592                              State.FloatPointerInfo);
1593 
1594   SDValue IntPtr;
1595   if (DataLayout.isBigEndian()) {
1596     assert(FloatVT.isByteSized() && "Unsupported floating point type!");
1597     // Load out a legal integer with the same sign bit as the float.
1598     IntPtr = StackPtr;
1599     State.IntPointerInfo = State.FloatPointerInfo;
1600   } else {
1601     // Advance the pointer so that the loaded byte will contain the sign bit.
1602     unsigned ByteOffset = (NumBits / 8) - 1;
1603     IntPtr =
1604         DAG.getMemBasePlusOffset(StackPtr, TypeSize::getFixed(ByteOffset), DL);
1605     State.IntPointerInfo = MachinePointerInfo::getFixedStack(MF, FI,
1606                                                              ByteOffset);
1607   }
1608 
1609   State.IntPtr = IntPtr;
1610   State.IntValue = DAG.getExtLoad(ISD::EXTLOAD, DL, LoadTy, State.Chain, IntPtr,
1611                                   State.IntPointerInfo, MVT::i8);
1612   State.SignMask = APInt::getOneBitSet(LoadTy.getScalarSizeInBits(), 7);
1613   State.SignBit = 7;
1614 }
1615 
1616 /// Replace the integer value produced by getSignAsIntValue() with a new value
1617 /// and cast the result back to a floating-point type.
1618 SDValue SelectionDAGLegalize::modifySignAsInt(const FloatSignAsInt &State,
1619                                               const SDLoc &DL,
1620                                               SDValue NewIntValue) const {
1621   if (!State.Chain)
1622     return DAG.getNode(ISD::BITCAST, DL, State.FloatVT, NewIntValue);
1623 
1624   // Override the part containing the sign bit in the value stored on the stack.
1625   SDValue Chain = DAG.getTruncStore(State.Chain, DL, NewIntValue, State.IntPtr,
1626                                     State.IntPointerInfo, MVT::i8);
1627   return DAG.getLoad(State.FloatVT, DL, Chain, State.FloatPtr,
1628                      State.FloatPointerInfo);
1629 }
1630 
1631 SDValue SelectionDAGLegalize::ExpandFCOPYSIGN(SDNode *Node) const {
1632   SDLoc DL(Node);
1633   SDValue Mag = Node->getOperand(0);
1634   SDValue Sign = Node->getOperand(1);
1635 
1636   // Get sign bit into an integer value.
1637   FloatSignAsInt SignAsInt;
1638   getSignAsIntValue(SignAsInt, DL, Sign);
1639 
1640   EVT IntVT = SignAsInt.IntValue.getValueType();
1641   SDValue SignMask = DAG.getConstant(SignAsInt.SignMask, DL, IntVT);
1642   SDValue SignBit = DAG.getNode(ISD::AND, DL, IntVT, SignAsInt.IntValue,
1643                                 SignMask);
1644 
1645   // If FABS is legal transform FCOPYSIGN(x, y) => sign(x) ? -FABS(x) : FABS(X)
1646   EVT FloatVT = Mag.getValueType();
1647   if (TLI.isOperationLegalOrCustom(ISD::FABS, FloatVT) &&
1648       TLI.isOperationLegalOrCustom(ISD::FNEG, FloatVT)) {
1649     SDValue AbsValue = DAG.getNode(ISD::FABS, DL, FloatVT, Mag);
1650     SDValue NegValue = DAG.getNode(ISD::FNEG, DL, FloatVT, AbsValue);
1651     SDValue Cond = DAG.getSetCC(DL, getSetCCResultType(IntVT), SignBit,
1652                                 DAG.getConstant(0, DL, IntVT), ISD::SETNE);
1653     return DAG.getSelect(DL, FloatVT, Cond, NegValue, AbsValue);
1654   }
1655 
1656   // Transform Mag value to integer, and clear the sign bit.
1657   FloatSignAsInt MagAsInt;
1658   getSignAsIntValue(MagAsInt, DL, Mag);
1659   EVT MagVT = MagAsInt.IntValue.getValueType();
1660   SDValue ClearSignMask = DAG.getConstant(~MagAsInt.SignMask, DL, MagVT);
1661   SDValue ClearedSign = DAG.getNode(ISD::AND, DL, MagVT, MagAsInt.IntValue,
1662                                     ClearSignMask);
1663 
1664   // Get the signbit at the right position for MagAsInt.
1665   int ShiftAmount = SignAsInt.SignBit - MagAsInt.SignBit;
1666   EVT ShiftVT = IntVT;
1667   if (SignBit.getScalarValueSizeInBits() <
1668       ClearedSign.getScalarValueSizeInBits()) {
1669     SignBit = DAG.getNode(ISD::ZERO_EXTEND, DL, MagVT, SignBit);
1670     ShiftVT = MagVT;
1671   }
1672   if (ShiftAmount > 0) {
1673     SDValue ShiftCnst = DAG.getConstant(ShiftAmount, DL, ShiftVT);
1674     SignBit = DAG.getNode(ISD::SRL, DL, ShiftVT, SignBit, ShiftCnst);
1675   } else if (ShiftAmount < 0) {
1676     SDValue ShiftCnst = DAG.getConstant(-ShiftAmount, DL, ShiftVT);
1677     SignBit = DAG.getNode(ISD::SHL, DL, ShiftVT, SignBit, ShiftCnst);
1678   }
1679   if (SignBit.getScalarValueSizeInBits() >
1680       ClearedSign.getScalarValueSizeInBits()) {
1681     SignBit = DAG.getNode(ISD::TRUNCATE, DL, MagVT, SignBit);
1682   }
1683 
1684   SDNodeFlags Flags;
1685   Flags.setDisjoint(true);
1686 
1687   // Store the part with the modified sign and convert back to float.
1688   SDValue CopiedSign =
1689       DAG.getNode(ISD::OR, DL, MagVT, ClearedSign, SignBit, Flags);
1690 
1691   return modifySignAsInt(MagAsInt, DL, CopiedSign);
1692 }
1693 
1694 SDValue SelectionDAGLegalize::ExpandFNEG(SDNode *Node) const {
1695   // Get the sign bit as an integer.
1696   SDLoc DL(Node);
1697   FloatSignAsInt SignAsInt;
1698   getSignAsIntValue(SignAsInt, DL, Node->getOperand(0));
1699   EVT IntVT = SignAsInt.IntValue.getValueType();
1700 
1701   // Flip the sign.
1702   SDValue SignMask = DAG.getConstant(SignAsInt.SignMask, DL, IntVT);
1703   SDValue SignFlip =
1704       DAG.getNode(ISD::XOR, DL, IntVT, SignAsInt.IntValue, SignMask);
1705 
1706   // Convert back to float.
1707   return modifySignAsInt(SignAsInt, DL, SignFlip);
1708 }
1709 
1710 SDValue SelectionDAGLegalize::ExpandFABS(SDNode *Node) const {
1711   SDLoc DL(Node);
1712   SDValue Value = Node->getOperand(0);
1713 
1714   // Transform FABS(x) => FCOPYSIGN(x, 0.0) if FCOPYSIGN is legal.
1715   EVT FloatVT = Value.getValueType();
1716   if (TLI.isOperationLegalOrCustom(ISD::FCOPYSIGN, FloatVT)) {
1717     SDValue Zero = DAG.getConstantFP(0.0, DL, FloatVT);
1718     return DAG.getNode(ISD::FCOPYSIGN, DL, FloatVT, Value, Zero);
1719   }
1720 
1721   // Transform value to integer, clear the sign bit and transform back.
1722   FloatSignAsInt ValueAsInt;
1723   getSignAsIntValue(ValueAsInt, DL, Value);
1724   EVT IntVT = ValueAsInt.IntValue.getValueType();
1725   SDValue ClearSignMask = DAG.getConstant(~ValueAsInt.SignMask, DL, IntVT);
1726   SDValue ClearedSign = DAG.getNode(ISD::AND, DL, IntVT, ValueAsInt.IntValue,
1727                                     ClearSignMask);
1728   return modifySignAsInt(ValueAsInt, DL, ClearedSign);
1729 }
1730 
1731 void SelectionDAGLegalize::ExpandDYNAMIC_STACKALLOC(SDNode* Node,
1732                                            SmallVectorImpl<SDValue> &Results) {
1733   Register SPReg = TLI.getStackPointerRegisterToSaveRestore();
1734   assert(SPReg && "Target cannot require DYNAMIC_STACKALLOC expansion and"
1735           " not tell us which reg is the stack pointer!");
1736   SDLoc dl(Node);
1737   EVT VT = Node->getValueType(0);
1738   SDValue Tmp1 = SDValue(Node, 0);
1739   SDValue Tmp2 = SDValue(Node, 1);
1740   SDValue Tmp3 = Node->getOperand(2);
1741   SDValue Chain = Tmp1.getOperand(0);
1742 
1743   // Chain the dynamic stack allocation so that it doesn't modify the stack
1744   // pointer when other instructions are using the stack.
1745   Chain = DAG.getCALLSEQ_START(Chain, 0, 0, dl);
1746 
1747   SDValue Size  = Tmp2.getOperand(1);
1748   SDValue SP = DAG.getCopyFromReg(Chain, dl, SPReg, VT);
1749   Chain = SP.getValue(1);
1750   Align Alignment = cast<ConstantSDNode>(Tmp3)->getAlignValue();
1751   const TargetFrameLowering *TFL = DAG.getSubtarget().getFrameLowering();
1752   unsigned Opc =
1753     TFL->getStackGrowthDirection() == TargetFrameLowering::StackGrowsUp ?
1754     ISD::ADD : ISD::SUB;
1755 
1756   Align StackAlign = TFL->getStackAlign();
1757   Tmp1 = DAG.getNode(Opc, dl, VT, SP, Size);       // Value
1758   if (Alignment > StackAlign)
1759     Tmp1 = DAG.getNode(ISD::AND, dl, VT, Tmp1,
1760                        DAG.getConstant(-Alignment.value(), dl, VT));
1761   Chain = DAG.getCopyToReg(Chain, dl, SPReg, Tmp1);     // Output chain
1762 
1763   Tmp2 = DAG.getCALLSEQ_END(Chain, 0, 0, SDValue(), dl);
1764 
1765   Results.push_back(Tmp1);
1766   Results.push_back(Tmp2);
1767 }
1768 
1769 /// Emit a store/load combination to the stack.  This stores
1770 /// SrcOp to a stack slot of type SlotVT, truncating it if needed.  It then does
1771 /// a load from the stack slot to DestVT, extending it if needed.
1772 /// The resultant code need not be legal.
1773 SDValue SelectionDAGLegalize::EmitStackConvert(SDValue SrcOp, EVT SlotVT,
1774                                                EVT DestVT, const SDLoc &dl) {
1775   return EmitStackConvert(SrcOp, SlotVT, DestVT, dl, DAG.getEntryNode());
1776 }
1777 
1778 SDValue SelectionDAGLegalize::EmitStackConvert(SDValue SrcOp, EVT SlotVT,
1779                                                EVT DestVT, const SDLoc &dl,
1780                                                SDValue Chain) {
1781   EVT SrcVT = SrcOp.getValueType();
1782   Type *DestType = DestVT.getTypeForEVT(*DAG.getContext());
1783   Align DestAlign = DAG.getDataLayout().getPrefTypeAlign(DestType);
1784 
1785   // Don't convert with stack if the load/store is expensive.
1786   if ((SrcVT.bitsGT(SlotVT) &&
1787        !TLI.isTruncStoreLegalOrCustom(SrcOp.getValueType(), SlotVT)) ||
1788       (SlotVT.bitsLT(DestVT) &&
1789        !TLI.isLoadExtLegalOrCustom(ISD::EXTLOAD, DestVT, SlotVT)))
1790     return SDValue();
1791 
1792   // Create the stack frame object.
1793   Align SrcAlign = DAG.getDataLayout().getPrefTypeAlign(
1794       SrcOp.getValueType().getTypeForEVT(*DAG.getContext()));
1795   SDValue FIPtr = DAG.CreateStackTemporary(SlotVT.getStoreSize(), SrcAlign);
1796 
1797   FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(FIPtr);
1798   int SPFI = StackPtrFI->getIndex();
1799   MachinePointerInfo PtrInfo =
1800       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI);
1801 
1802   // Emit a store to the stack slot.  Use a truncstore if the input value is
1803   // later than DestVT.
1804   SDValue Store;
1805 
1806   if (SrcVT.bitsGT(SlotVT))
1807     Store = DAG.getTruncStore(Chain, dl, SrcOp, FIPtr, PtrInfo,
1808                               SlotVT, SrcAlign);
1809   else {
1810     assert(SrcVT.bitsEq(SlotVT) && "Invalid store");
1811     Store = DAG.getStore(Chain, dl, SrcOp, FIPtr, PtrInfo, SrcAlign);
1812   }
1813 
1814   // Result is a load from the stack slot.
1815   if (SlotVT.bitsEq(DestVT))
1816     return DAG.getLoad(DestVT, dl, Store, FIPtr, PtrInfo, DestAlign);
1817 
1818   assert(SlotVT.bitsLT(DestVT) && "Unknown extension!");
1819   return DAG.getExtLoad(ISD::EXTLOAD, dl, DestVT, Store, FIPtr, PtrInfo, SlotVT,
1820                         DestAlign);
1821 }
1822 
1823 SDValue SelectionDAGLegalize::ExpandSCALAR_TO_VECTOR(SDNode *Node) {
1824   SDLoc dl(Node);
1825   // Create a vector sized/aligned stack slot, store the value to element #0,
1826   // then load the whole vector back out.
1827   SDValue StackPtr = DAG.CreateStackTemporary(Node->getValueType(0));
1828 
1829   FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(StackPtr);
1830   int SPFI = StackPtrFI->getIndex();
1831 
1832   SDValue Ch = DAG.getTruncStore(
1833       DAG.getEntryNode(), dl, Node->getOperand(0), StackPtr,
1834       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI),
1835       Node->getValueType(0).getVectorElementType());
1836   return DAG.getLoad(
1837       Node->getValueType(0), dl, Ch, StackPtr,
1838       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI));
1839 }
1840 
1841 static bool
1842 ExpandBVWithShuffles(SDNode *Node, SelectionDAG &DAG,
1843                      const TargetLowering &TLI, SDValue &Res) {
1844   unsigned NumElems = Node->getNumOperands();
1845   SDLoc dl(Node);
1846   EVT VT = Node->getValueType(0);
1847 
1848   // Try to group the scalars into pairs, shuffle the pairs together, then
1849   // shuffle the pairs of pairs together, etc. until the vector has
1850   // been built. This will work only if all of the necessary shuffle masks
1851   // are legal.
1852 
1853   // We do this in two phases; first to check the legality of the shuffles,
1854   // and next, assuming that all shuffles are legal, to create the new nodes.
1855   for (int Phase = 0; Phase < 2; ++Phase) {
1856     SmallVector<std::pair<SDValue, SmallVector<int, 16>>, 16> IntermedVals,
1857                                                               NewIntermedVals;
1858     for (unsigned i = 0; i < NumElems; ++i) {
1859       SDValue V = Node->getOperand(i);
1860       if (V.isUndef())
1861         continue;
1862 
1863       SDValue Vec;
1864       if (Phase)
1865         Vec = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, V);
1866       IntermedVals.push_back(std::make_pair(Vec, SmallVector<int, 16>(1, i)));
1867     }
1868 
1869     while (IntermedVals.size() > 2) {
1870       NewIntermedVals.clear();
1871       for (unsigned i = 0, e = (IntermedVals.size() & ~1u); i < e; i += 2) {
1872         // This vector and the next vector are shuffled together (simply to
1873         // append the one to the other).
1874         SmallVector<int, 16> ShuffleVec(NumElems, -1);
1875 
1876         SmallVector<int, 16> FinalIndices;
1877         FinalIndices.reserve(IntermedVals[i].second.size() +
1878                              IntermedVals[i+1].second.size());
1879 
1880         int k = 0;
1881         for (unsigned j = 0, f = IntermedVals[i].second.size(); j != f;
1882              ++j, ++k) {
1883           ShuffleVec[k] = j;
1884           FinalIndices.push_back(IntermedVals[i].second[j]);
1885         }
1886         for (unsigned j = 0, f = IntermedVals[i+1].second.size(); j != f;
1887              ++j, ++k) {
1888           ShuffleVec[k] = NumElems + j;
1889           FinalIndices.push_back(IntermedVals[i+1].second[j]);
1890         }
1891 
1892         SDValue Shuffle;
1893         if (Phase)
1894           Shuffle = DAG.getVectorShuffle(VT, dl, IntermedVals[i].first,
1895                                          IntermedVals[i+1].first,
1896                                          ShuffleVec);
1897         else if (!TLI.isShuffleMaskLegal(ShuffleVec, VT))
1898           return false;
1899         NewIntermedVals.push_back(
1900             std::make_pair(Shuffle, std::move(FinalIndices)));
1901       }
1902 
1903       // If we had an odd number of defined values, then append the last
1904       // element to the array of new vectors.
1905       if ((IntermedVals.size() & 1) != 0)
1906         NewIntermedVals.push_back(IntermedVals.back());
1907 
1908       IntermedVals.swap(NewIntermedVals);
1909     }
1910 
1911     assert(IntermedVals.size() <= 2 && IntermedVals.size() > 0 &&
1912            "Invalid number of intermediate vectors");
1913     SDValue Vec1 = IntermedVals[0].first;
1914     SDValue Vec2;
1915     if (IntermedVals.size() > 1)
1916       Vec2 = IntermedVals[1].first;
1917     else if (Phase)
1918       Vec2 = DAG.getUNDEF(VT);
1919 
1920     SmallVector<int, 16> ShuffleVec(NumElems, -1);
1921     for (unsigned i = 0, e = IntermedVals[0].second.size(); i != e; ++i)
1922       ShuffleVec[IntermedVals[0].second[i]] = i;
1923     for (unsigned i = 0, e = IntermedVals[1].second.size(); i != e; ++i)
1924       ShuffleVec[IntermedVals[1].second[i]] = NumElems + i;
1925 
1926     if (Phase)
1927       Res = DAG.getVectorShuffle(VT, dl, Vec1, Vec2, ShuffleVec);
1928     else if (!TLI.isShuffleMaskLegal(ShuffleVec, VT))
1929       return false;
1930   }
1931 
1932   return true;
1933 }
1934 
1935 /// Expand a BUILD_VECTOR node on targets that don't
1936 /// support the operation, but do support the resultant vector type.
1937 SDValue SelectionDAGLegalize::ExpandBUILD_VECTOR(SDNode *Node) {
1938   unsigned NumElems = Node->getNumOperands();
1939   SDValue Value1, Value2;
1940   SDLoc dl(Node);
1941   EVT VT = Node->getValueType(0);
1942   EVT OpVT = Node->getOperand(0).getValueType();
1943   EVT EltVT = VT.getVectorElementType();
1944 
1945   // If the only non-undef value is the low element, turn this into a
1946   // SCALAR_TO_VECTOR node.  If this is { X, X, X, X }, determine X.
1947   bool isOnlyLowElement = true;
1948   bool MoreThanTwoValues = false;
1949   bool isConstant = true;
1950   for (unsigned i = 0; i < NumElems; ++i) {
1951     SDValue V = Node->getOperand(i);
1952     if (V.isUndef())
1953       continue;
1954     if (i > 0)
1955       isOnlyLowElement = false;
1956     if (!isa<ConstantFPSDNode>(V) && !isa<ConstantSDNode>(V))
1957       isConstant = false;
1958 
1959     if (!Value1.getNode()) {
1960       Value1 = V;
1961     } else if (!Value2.getNode()) {
1962       if (V != Value1)
1963         Value2 = V;
1964     } else if (V != Value1 && V != Value2) {
1965       MoreThanTwoValues = true;
1966     }
1967   }
1968 
1969   if (!Value1.getNode())
1970     return DAG.getUNDEF(VT);
1971 
1972   if (isOnlyLowElement)
1973     return DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Node->getOperand(0));
1974 
1975   // If all elements are constants, create a load from the constant pool.
1976   if (isConstant) {
1977     SmallVector<Constant*, 16> CV;
1978     for (unsigned i = 0, e = NumElems; i != e; ++i) {
1979       if (ConstantFPSDNode *V =
1980           dyn_cast<ConstantFPSDNode>(Node->getOperand(i))) {
1981         CV.push_back(const_cast<ConstantFP *>(V->getConstantFPValue()));
1982       } else if (ConstantSDNode *V =
1983                  dyn_cast<ConstantSDNode>(Node->getOperand(i))) {
1984         if (OpVT==EltVT)
1985           CV.push_back(const_cast<ConstantInt *>(V->getConstantIntValue()));
1986         else {
1987           // If OpVT and EltVT don't match, EltVT is not legal and the
1988           // element values have been promoted/truncated earlier.  Undo this;
1989           // we don't want a v16i8 to become a v16i32 for example.
1990           const ConstantInt *CI = V->getConstantIntValue();
1991           CV.push_back(ConstantInt::get(EltVT.getTypeForEVT(*DAG.getContext()),
1992                                         CI->getZExtValue()));
1993         }
1994       } else {
1995         assert(Node->getOperand(i).isUndef());
1996         Type *OpNTy = EltVT.getTypeForEVT(*DAG.getContext());
1997         CV.push_back(UndefValue::get(OpNTy));
1998       }
1999     }
2000     Constant *CP = ConstantVector::get(CV);
2001     SDValue CPIdx =
2002         DAG.getConstantPool(CP, TLI.getPointerTy(DAG.getDataLayout()));
2003     Align Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlign();
2004     return DAG.getLoad(
2005         VT, dl, DAG.getEntryNode(), CPIdx,
2006         MachinePointerInfo::getConstantPool(DAG.getMachineFunction()),
2007         Alignment);
2008   }
2009 
2010   SmallSet<SDValue, 16> DefinedValues;
2011   for (unsigned i = 0; i < NumElems; ++i) {
2012     if (Node->getOperand(i).isUndef())
2013       continue;
2014     DefinedValues.insert(Node->getOperand(i));
2015   }
2016 
2017   if (TLI.shouldExpandBuildVectorWithShuffles(VT, DefinedValues.size())) {
2018     if (!MoreThanTwoValues) {
2019       SmallVector<int, 8> ShuffleVec(NumElems, -1);
2020       for (unsigned i = 0; i < NumElems; ++i) {
2021         SDValue V = Node->getOperand(i);
2022         if (V.isUndef())
2023           continue;
2024         ShuffleVec[i] = V == Value1 ? 0 : NumElems;
2025       }
2026       if (TLI.isShuffleMaskLegal(ShuffleVec, Node->getValueType(0))) {
2027         // Get the splatted value into the low element of a vector register.
2028         SDValue Vec1 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value1);
2029         SDValue Vec2;
2030         if (Value2.getNode())
2031           Vec2 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value2);
2032         else
2033           Vec2 = DAG.getUNDEF(VT);
2034 
2035         // Return shuffle(LowValVec, undef, <0,0,0,0>)
2036         return DAG.getVectorShuffle(VT, dl, Vec1, Vec2, ShuffleVec);
2037       }
2038     } else {
2039       SDValue Res;
2040       if (ExpandBVWithShuffles(Node, DAG, TLI, Res))
2041         return Res;
2042     }
2043   }
2044 
2045   // Otherwise, we can't handle this case efficiently.
2046   return ExpandVectorBuildThroughStack(Node);
2047 }
2048 
2049 SDValue SelectionDAGLegalize::ExpandSPLAT_VECTOR(SDNode *Node) {
2050   SDLoc DL(Node);
2051   EVT VT = Node->getValueType(0);
2052   SDValue SplatVal = Node->getOperand(0);
2053 
2054   return DAG.getSplatBuildVector(VT, DL, SplatVal);
2055 }
2056 
2057 // Expand a node into a call to a libcall, returning the value as the first
2058 // result and the chain as the second.  If the result value does not fit into a
2059 // register, return the lo part and set the hi part to the by-reg argument in
2060 // the first.  If it does fit into a single register, return the result and
2061 // leave the Hi part unset.
2062 std::pair<SDValue, SDValue> SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, SDNode *Node,
2063                                             TargetLowering::ArgListTy &&Args,
2064                                             bool isSigned) {
2065   EVT CodePtrTy = TLI.getPointerTy(DAG.getDataLayout());
2066   SDValue Callee;
2067   if (const char *LibcallName = TLI.getLibcallName(LC))
2068     Callee = DAG.getExternalSymbol(LibcallName, CodePtrTy);
2069   else {
2070     Callee = DAG.getUNDEF(CodePtrTy);
2071     DAG.getContext()->emitError(Twine("no libcall available for ") +
2072                                 Node->getOperationName(&DAG));
2073   }
2074 
2075   EVT RetVT = Node->getValueType(0);
2076   Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
2077 
2078   // By default, the input chain to this libcall is the entry node of the
2079   // function. If the libcall is going to be emitted as a tail call then
2080   // TLI.isUsedByReturnOnly will change it to the right chain if the return
2081   // node which is being folded has a non-entry input chain.
2082   SDValue InChain = DAG.getEntryNode();
2083 
2084   // isTailCall may be true since the callee does not reference caller stack
2085   // frame. Check if it's in the right position and that the return types match.
2086   SDValue TCChain = InChain;
2087   const Function &F = DAG.getMachineFunction().getFunction();
2088   bool isTailCall =
2089       TLI.isInTailCallPosition(DAG, Node, TCChain) &&
2090       (RetTy == F.getReturnType() || F.getReturnType()->isVoidTy());
2091   if (isTailCall)
2092     InChain = TCChain;
2093 
2094   TargetLowering::CallLoweringInfo CLI(DAG);
2095   bool signExtend = TLI.shouldSignExtendTypeInLibCall(RetVT, isSigned);
2096   CLI.setDebugLoc(SDLoc(Node))
2097       .setChain(InChain)
2098       .setLibCallee(TLI.getLibcallCallingConv(LC), RetTy, Callee,
2099                     std::move(Args))
2100       .setTailCall(isTailCall)
2101       .setSExtResult(signExtend)
2102       .setZExtResult(!signExtend)
2103       .setIsPostTypeLegalization(true);
2104 
2105   std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
2106 
2107   if (!CallInfo.second.getNode()) {
2108     LLVM_DEBUG(dbgs() << "Created tailcall: "; DAG.getRoot().dump(&DAG));
2109     // It's a tailcall, return the chain (which is the DAG root).
2110     return {DAG.getRoot(), DAG.getRoot()};
2111   }
2112 
2113   LLVM_DEBUG(dbgs() << "Created libcall: "; CallInfo.first.dump(&DAG));
2114   return CallInfo;
2115 }
2116 
2117 std::pair<SDValue, SDValue> SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, SDNode *Node,
2118                                             bool isSigned) {
2119   TargetLowering::ArgListTy Args;
2120   TargetLowering::ArgListEntry Entry;
2121   for (const SDValue &Op : Node->op_values()) {
2122     EVT ArgVT = Op.getValueType();
2123     Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
2124     Entry.Node = Op;
2125     Entry.Ty = ArgTy;
2126     Entry.IsSExt = TLI.shouldSignExtendTypeInLibCall(ArgVT, isSigned);
2127     Entry.IsZExt = !Entry.IsSExt;
2128     Args.push_back(Entry);
2129   }
2130 
2131   return ExpandLibCall(LC, Node, std::move(Args), isSigned);
2132 }
2133 
2134 void SelectionDAGLegalize::ExpandFrexpLibCall(
2135     SDNode *Node, SmallVectorImpl<SDValue> &Results) {
2136   SDLoc dl(Node);
2137   EVT VT = Node->getValueType(0);
2138   EVT ExpVT = Node->getValueType(1);
2139 
2140   SDValue FPOp = Node->getOperand(0);
2141 
2142   EVT ArgVT = FPOp.getValueType();
2143   Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
2144 
2145   TargetLowering::ArgListEntry FPArgEntry;
2146   FPArgEntry.Node = FPOp;
2147   FPArgEntry.Ty = ArgTy;
2148 
2149   SDValue StackSlot = DAG.CreateStackTemporary(ExpVT);
2150   TargetLowering::ArgListEntry PtrArgEntry;
2151   PtrArgEntry.Node = StackSlot;
2152   PtrArgEntry.Ty = PointerType::get(*DAG.getContext(),
2153                                     DAG.getDataLayout().getAllocaAddrSpace());
2154 
2155   TargetLowering::ArgListTy Args = {FPArgEntry, PtrArgEntry};
2156 
2157   RTLIB::Libcall LC = RTLIB::getFREXP(VT);
2158   auto [Call, Chain] = ExpandLibCall(LC, Node, std::move(Args), false);
2159 
2160   // FIXME: Get type of int for libcall declaration and cast
2161 
2162   int FrameIdx = cast<FrameIndexSDNode>(StackSlot)->getIndex();
2163   auto PtrInfo =
2164       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FrameIdx);
2165 
2166   SDValue LoadExp = DAG.getLoad(ExpVT, dl, Chain, StackSlot, PtrInfo);
2167   SDValue OutputChain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
2168                                     LoadExp.getValue(1), DAG.getRoot());
2169   DAG.setRoot(OutputChain);
2170 
2171   Results.push_back(Call);
2172   Results.push_back(LoadExp);
2173 }
2174 
2175 void SelectionDAGLegalize::ExpandFPLibCall(SDNode* Node,
2176                                            RTLIB::Libcall LC,
2177                                            SmallVectorImpl<SDValue> &Results) {
2178   if (LC == RTLIB::UNKNOWN_LIBCALL)
2179     llvm_unreachable("Can't create an unknown libcall!");
2180 
2181   if (Node->isStrictFPOpcode()) {
2182     EVT RetVT = Node->getValueType(0);
2183     SmallVector<SDValue, 4> Ops(drop_begin(Node->ops()));
2184     TargetLowering::MakeLibCallOptions CallOptions;
2185     // FIXME: This doesn't support tail calls.
2186     std::pair<SDValue, SDValue> Tmp = TLI.makeLibCall(DAG, LC, RetVT,
2187                                                       Ops, CallOptions,
2188                                                       SDLoc(Node),
2189                                                       Node->getOperand(0));
2190     Results.push_back(Tmp.first);
2191     Results.push_back(Tmp.second);
2192   } else {
2193     bool IsSignedArgument = Node->getOpcode() == ISD::FLDEXP;
2194     SDValue Tmp = ExpandLibCall(LC, Node, IsSignedArgument).first;
2195     Results.push_back(Tmp);
2196   }
2197 }
2198 
2199 /// Expand the node to a libcall based on the result type.
2200 void SelectionDAGLegalize::ExpandFPLibCall(SDNode* Node,
2201                                            RTLIB::Libcall Call_F32,
2202                                            RTLIB::Libcall Call_F64,
2203                                            RTLIB::Libcall Call_F80,
2204                                            RTLIB::Libcall Call_F128,
2205                                            RTLIB::Libcall Call_PPCF128,
2206                                            SmallVectorImpl<SDValue> &Results) {
2207   RTLIB::Libcall LC = RTLIB::getFPLibCall(Node->getSimpleValueType(0),
2208                                           Call_F32, Call_F64, Call_F80,
2209                                           Call_F128, Call_PPCF128);
2210   ExpandFPLibCall(Node, LC, Results);
2211 }
2212 
2213 SDValue SelectionDAGLegalize::ExpandIntLibCall(SDNode* Node, bool isSigned,
2214                                                RTLIB::Libcall Call_I8,
2215                                                RTLIB::Libcall Call_I16,
2216                                                RTLIB::Libcall Call_I32,
2217                                                RTLIB::Libcall Call_I64,
2218                                                RTLIB::Libcall Call_I128) {
2219   RTLIB::Libcall LC;
2220   switch (Node->getSimpleValueType(0).SimpleTy) {
2221   default: llvm_unreachable("Unexpected request for libcall!");
2222   case MVT::i8:   LC = Call_I8; break;
2223   case MVT::i16:  LC = Call_I16; break;
2224   case MVT::i32:  LC = Call_I32; break;
2225   case MVT::i64:  LC = Call_I64; break;
2226   case MVT::i128: LC = Call_I128; break;
2227   }
2228   return ExpandLibCall(LC, Node, isSigned).first;
2229 }
2230 
2231 /// Expand the node to a libcall based on first argument type (for instance
2232 /// lround and its variant).
2233 void SelectionDAGLegalize::ExpandArgFPLibCall(SDNode* Node,
2234                                             RTLIB::Libcall Call_F32,
2235                                             RTLIB::Libcall Call_F64,
2236                                             RTLIB::Libcall Call_F80,
2237                                             RTLIB::Libcall Call_F128,
2238                                             RTLIB::Libcall Call_PPCF128,
2239                                             SmallVectorImpl<SDValue> &Results) {
2240   EVT InVT = Node->getOperand(Node->isStrictFPOpcode() ? 1 : 0).getValueType();
2241   RTLIB::Libcall LC = RTLIB::getFPLibCall(InVT.getSimpleVT(),
2242                                           Call_F32, Call_F64, Call_F80,
2243                                           Call_F128, Call_PPCF128);
2244   ExpandFPLibCall(Node, LC, Results);
2245 }
2246 
2247 /// Issue libcalls to __{u}divmod to compute div / rem pairs.
2248 void
2249 SelectionDAGLegalize::ExpandDivRemLibCall(SDNode *Node,
2250                                           SmallVectorImpl<SDValue> &Results) {
2251   unsigned Opcode = Node->getOpcode();
2252   bool isSigned = Opcode == ISD::SDIVREM;
2253 
2254   RTLIB::Libcall LC;
2255   switch (Node->getSimpleValueType(0).SimpleTy) {
2256   default: llvm_unreachable("Unexpected request for libcall!");
2257   case MVT::i8:   LC= isSigned ? RTLIB::SDIVREM_I8  : RTLIB::UDIVREM_I8;  break;
2258   case MVT::i16:  LC= isSigned ? RTLIB::SDIVREM_I16 : RTLIB::UDIVREM_I16; break;
2259   case MVT::i32:  LC= isSigned ? RTLIB::SDIVREM_I32 : RTLIB::UDIVREM_I32; break;
2260   case MVT::i64:  LC= isSigned ? RTLIB::SDIVREM_I64 : RTLIB::UDIVREM_I64; break;
2261   case MVT::i128: LC= isSigned ? RTLIB::SDIVREM_I128:RTLIB::UDIVREM_I128; break;
2262   }
2263 
2264   // The input chain to this libcall is the entry node of the function.
2265   // Legalizing the call will automatically add the previous call to the
2266   // dependence.
2267   SDValue InChain = DAG.getEntryNode();
2268 
2269   EVT RetVT = Node->getValueType(0);
2270   Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
2271 
2272   TargetLowering::ArgListTy Args;
2273   TargetLowering::ArgListEntry Entry;
2274   for (const SDValue &Op : Node->op_values()) {
2275     EVT ArgVT = Op.getValueType();
2276     Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
2277     Entry.Node = Op;
2278     Entry.Ty = ArgTy;
2279     Entry.IsSExt = isSigned;
2280     Entry.IsZExt = !isSigned;
2281     Args.push_back(Entry);
2282   }
2283 
2284   // Also pass the return address of the remainder.
2285   SDValue FIPtr = DAG.CreateStackTemporary(RetVT);
2286   Entry.Node = FIPtr;
2287   Entry.Ty = PointerType::getUnqual(RetTy->getContext());
2288   Entry.IsSExt = isSigned;
2289   Entry.IsZExt = !isSigned;
2290   Args.push_back(Entry);
2291 
2292   SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
2293                                          TLI.getPointerTy(DAG.getDataLayout()));
2294 
2295   SDLoc dl(Node);
2296   TargetLowering::CallLoweringInfo CLI(DAG);
2297   CLI.setDebugLoc(dl)
2298       .setChain(InChain)
2299       .setLibCallee(TLI.getLibcallCallingConv(LC), RetTy, Callee,
2300                     std::move(Args))
2301       .setSExtResult(isSigned)
2302       .setZExtResult(!isSigned);
2303 
2304   std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
2305 
2306   // Remainder is loaded back from the stack frame.
2307   SDValue Rem =
2308       DAG.getLoad(RetVT, dl, CallInfo.second, FIPtr, MachinePointerInfo());
2309   Results.push_back(CallInfo.first);
2310   Results.push_back(Rem);
2311 }
2312 
2313 /// Return true if sincos libcall is available.
2314 static bool isSinCosLibcallAvailable(SDNode *Node, const TargetLowering &TLI) {
2315   RTLIB::Libcall LC;
2316   switch (Node->getSimpleValueType(0).SimpleTy) {
2317   default: llvm_unreachable("Unexpected request for libcall!");
2318   case MVT::f32:     LC = RTLIB::SINCOS_F32; break;
2319   case MVT::f64:     LC = RTLIB::SINCOS_F64; break;
2320   case MVT::f80:     LC = RTLIB::SINCOS_F80; break;
2321   case MVT::f128:    LC = RTLIB::SINCOS_F128; break;
2322   case MVT::ppcf128: LC = RTLIB::SINCOS_PPCF128; break;
2323   }
2324   return TLI.getLibcallName(LC) != nullptr;
2325 }
2326 
2327 /// Only issue sincos libcall if both sin and cos are needed.
2328 static bool useSinCos(SDNode *Node) {
2329   unsigned OtherOpcode = Node->getOpcode() == ISD::FSIN
2330     ? ISD::FCOS : ISD::FSIN;
2331 
2332   SDValue Op0 = Node->getOperand(0);
2333   for (const SDNode *User : Op0.getNode()->uses()) {
2334     if (User == Node)
2335       continue;
2336     // The other user might have been turned into sincos already.
2337     if (User->getOpcode() == OtherOpcode || User->getOpcode() == ISD::FSINCOS)
2338       return true;
2339   }
2340   return false;
2341 }
2342 
2343 /// Issue libcalls to sincos to compute sin / cos pairs.
2344 void
2345 SelectionDAGLegalize::ExpandSinCosLibCall(SDNode *Node,
2346                                           SmallVectorImpl<SDValue> &Results) {
2347   RTLIB::Libcall LC;
2348   switch (Node->getSimpleValueType(0).SimpleTy) {
2349   default: llvm_unreachable("Unexpected request for libcall!");
2350   case MVT::f32:     LC = RTLIB::SINCOS_F32; break;
2351   case MVT::f64:     LC = RTLIB::SINCOS_F64; break;
2352   case MVT::f80:     LC = RTLIB::SINCOS_F80; break;
2353   case MVT::f128:    LC = RTLIB::SINCOS_F128; break;
2354   case MVT::ppcf128: LC = RTLIB::SINCOS_PPCF128; break;
2355   }
2356 
2357   // The input chain to this libcall is the entry node of the function.
2358   // Legalizing the call will automatically add the previous call to the
2359   // dependence.
2360   SDValue InChain = DAG.getEntryNode();
2361 
2362   EVT RetVT = Node->getValueType(0);
2363   Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
2364 
2365   TargetLowering::ArgListTy Args;
2366   TargetLowering::ArgListEntry Entry;
2367 
2368   // Pass the argument.
2369   Entry.Node = Node->getOperand(0);
2370   Entry.Ty = RetTy;
2371   Entry.IsSExt = false;
2372   Entry.IsZExt = false;
2373   Args.push_back(Entry);
2374 
2375   // Pass the return address of sin.
2376   SDValue SinPtr = DAG.CreateStackTemporary(RetVT);
2377   Entry.Node = SinPtr;
2378   Entry.Ty = PointerType::getUnqual(RetTy->getContext());
2379   Entry.IsSExt = false;
2380   Entry.IsZExt = false;
2381   Args.push_back(Entry);
2382 
2383   // Also pass the return address of the cos.
2384   SDValue CosPtr = DAG.CreateStackTemporary(RetVT);
2385   Entry.Node = CosPtr;
2386   Entry.Ty = PointerType::getUnqual(RetTy->getContext());
2387   Entry.IsSExt = false;
2388   Entry.IsZExt = false;
2389   Args.push_back(Entry);
2390 
2391   SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
2392                                          TLI.getPointerTy(DAG.getDataLayout()));
2393 
2394   SDLoc dl(Node);
2395   TargetLowering::CallLoweringInfo CLI(DAG);
2396   CLI.setDebugLoc(dl).setChain(InChain).setLibCallee(
2397       TLI.getLibcallCallingConv(LC), Type::getVoidTy(*DAG.getContext()), Callee,
2398       std::move(Args));
2399 
2400   std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
2401 
2402   Results.push_back(
2403       DAG.getLoad(RetVT, dl, CallInfo.second, SinPtr, MachinePointerInfo()));
2404   Results.push_back(
2405       DAG.getLoad(RetVT, dl, CallInfo.second, CosPtr, MachinePointerInfo()));
2406 }
2407 
2408 SDValue SelectionDAGLegalize::expandLdexp(SDNode *Node) const {
2409   SDLoc dl(Node);
2410   EVT VT = Node->getValueType(0);
2411   SDValue X = Node->getOperand(0);
2412   SDValue N = Node->getOperand(1);
2413   EVT ExpVT = N.getValueType();
2414   EVT AsIntVT = VT.changeTypeToInteger();
2415   if (AsIntVT == EVT()) // TODO: How to handle f80?
2416     return SDValue();
2417 
2418   if (Node->getOpcode() == ISD::STRICT_FLDEXP) // TODO
2419     return SDValue();
2420 
2421   SDNodeFlags NSW;
2422   NSW.setNoSignedWrap(true);
2423   SDNodeFlags NUW_NSW;
2424   NUW_NSW.setNoUnsignedWrap(true);
2425   NUW_NSW.setNoSignedWrap(true);
2426 
2427   EVT SetCCVT =
2428       TLI.getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), ExpVT);
2429   const fltSemantics &FltSem = SelectionDAG::EVTToAPFloatSemantics(VT);
2430 
2431   const APFloat::ExponentType MaxExpVal = APFloat::semanticsMaxExponent(FltSem);
2432   const APFloat::ExponentType MinExpVal = APFloat::semanticsMinExponent(FltSem);
2433   const int Precision = APFloat::semanticsPrecision(FltSem);
2434 
2435   const SDValue MaxExp = DAG.getConstant(MaxExpVal, dl, ExpVT);
2436   const SDValue MinExp = DAG.getConstant(MinExpVal, dl, ExpVT);
2437 
2438   const SDValue DoubleMaxExp = DAG.getConstant(2 * MaxExpVal, dl, ExpVT);
2439 
2440   const APFloat One(FltSem, "1.0");
2441   APFloat ScaleUpK = scalbn(One, MaxExpVal, APFloat::rmNearestTiesToEven);
2442 
2443   // Offset by precision to avoid denormal range.
2444   APFloat ScaleDownK =
2445       scalbn(One, MinExpVal + Precision, APFloat::rmNearestTiesToEven);
2446 
2447   // TODO: Should really introduce control flow and use a block for the >
2448   // MaxExp, < MinExp cases
2449 
2450   // First, handle exponents Exp > MaxExp and scale down.
2451   SDValue NGtMaxExp = DAG.getSetCC(dl, SetCCVT, N, MaxExp, ISD::SETGT);
2452 
2453   SDValue DecN0 = DAG.getNode(ISD::SUB, dl, ExpVT, N, MaxExp, NSW);
2454   SDValue ClampMaxVal = DAG.getConstant(3 * MaxExpVal, dl, ExpVT);
2455   SDValue ClampN_Big = DAG.getNode(ISD::SMIN, dl, ExpVT, N, ClampMaxVal);
2456   SDValue DecN1 =
2457       DAG.getNode(ISD::SUB, dl, ExpVT, ClampN_Big, DoubleMaxExp, NSW);
2458 
2459   SDValue ScaleUpTwice =
2460       DAG.getSetCC(dl, SetCCVT, N, DoubleMaxExp, ISD::SETUGT);
2461 
2462   const SDValue ScaleUpVal = DAG.getConstantFP(ScaleUpK, dl, VT);
2463   SDValue ScaleUp0 = DAG.getNode(ISD::FMUL, dl, VT, X, ScaleUpVal);
2464   SDValue ScaleUp1 = DAG.getNode(ISD::FMUL, dl, VT, ScaleUp0, ScaleUpVal);
2465 
2466   SDValue SelectN_Big =
2467       DAG.getNode(ISD::SELECT, dl, ExpVT, ScaleUpTwice, DecN1, DecN0);
2468   SDValue SelectX_Big =
2469       DAG.getNode(ISD::SELECT, dl, VT, ScaleUpTwice, ScaleUp1, ScaleUp0);
2470 
2471   // Now handle exponents Exp < MinExp
2472   SDValue NLtMinExp = DAG.getSetCC(dl, SetCCVT, N, MinExp, ISD::SETLT);
2473 
2474   SDValue Increment0 = DAG.getConstant(-(MinExpVal + Precision), dl, ExpVT);
2475   SDValue Increment1 = DAG.getConstant(-2 * (MinExpVal + Precision), dl, ExpVT);
2476 
2477   SDValue IncN0 = DAG.getNode(ISD::ADD, dl, ExpVT, N, Increment0, NUW_NSW);
2478 
2479   SDValue ClampMinVal =
2480       DAG.getConstant(3 * MinExpVal + 2 * Precision, dl, ExpVT);
2481   SDValue ClampN_Small = DAG.getNode(ISD::SMAX, dl, ExpVT, N, ClampMinVal);
2482   SDValue IncN1 =
2483       DAG.getNode(ISD::ADD, dl, ExpVT, ClampN_Small, Increment1, NSW);
2484 
2485   const SDValue ScaleDownVal = DAG.getConstantFP(ScaleDownK, dl, VT);
2486   SDValue ScaleDown0 = DAG.getNode(ISD::FMUL, dl, VT, X, ScaleDownVal);
2487   SDValue ScaleDown1 = DAG.getNode(ISD::FMUL, dl, VT, ScaleDown0, ScaleDownVal);
2488 
2489   SDValue ScaleDownTwice = DAG.getSetCC(
2490       dl, SetCCVT, N, DAG.getConstant(2 * MinExpVal + Precision, dl, ExpVT),
2491       ISD::SETULT);
2492 
2493   SDValue SelectN_Small =
2494       DAG.getNode(ISD::SELECT, dl, ExpVT, ScaleDownTwice, IncN1, IncN0);
2495   SDValue SelectX_Small =
2496       DAG.getNode(ISD::SELECT, dl, VT, ScaleDownTwice, ScaleDown1, ScaleDown0);
2497 
2498   // Now combine the two out of range exponent handling cases with the base
2499   // case.
2500   SDValue NewX = DAG.getNode(
2501       ISD::SELECT, dl, VT, NGtMaxExp, SelectX_Big,
2502       DAG.getNode(ISD::SELECT, dl, VT, NLtMinExp, SelectX_Small, X));
2503 
2504   SDValue NewN = DAG.getNode(
2505       ISD::SELECT, dl, ExpVT, NGtMaxExp, SelectN_Big,
2506       DAG.getNode(ISD::SELECT, dl, ExpVT, NLtMinExp, SelectN_Small, N));
2507 
2508   SDValue BiasedN = DAG.getNode(ISD::ADD, dl, ExpVT, NewN, MaxExp, NSW);
2509 
2510   SDValue ExponentShiftAmt =
2511       DAG.getShiftAmountConstant(Precision - 1, ExpVT, dl);
2512   SDValue CastExpToValTy = DAG.getZExtOrTrunc(BiasedN, dl, AsIntVT);
2513 
2514   SDValue AsInt = DAG.getNode(ISD::SHL, dl, AsIntVT, CastExpToValTy,
2515                               ExponentShiftAmt, NUW_NSW);
2516   SDValue AsFP = DAG.getNode(ISD::BITCAST, dl, VT, AsInt);
2517   return DAG.getNode(ISD::FMUL, dl, VT, NewX, AsFP);
2518 }
2519 
2520 SDValue SelectionDAGLegalize::expandFrexp(SDNode *Node) const {
2521   SDLoc dl(Node);
2522   SDValue Val = Node->getOperand(0);
2523   EVT VT = Val.getValueType();
2524   EVT ExpVT = Node->getValueType(1);
2525   EVT AsIntVT = VT.changeTypeToInteger();
2526   if (AsIntVT == EVT()) // TODO: How to handle f80?
2527     return SDValue();
2528 
2529   const fltSemantics &FltSem = SelectionDAG::EVTToAPFloatSemantics(VT);
2530   const APFloat::ExponentType MinExpVal = APFloat::semanticsMinExponent(FltSem);
2531   const unsigned Precision = APFloat::semanticsPrecision(FltSem);
2532   const unsigned BitSize = VT.getScalarSizeInBits();
2533 
2534   // TODO: Could introduce control flow and skip over the denormal handling.
2535 
2536   // scale_up = fmul value, scalbn(1.0, precision + 1)
2537   // extracted_exp = (bitcast value to uint) >> precision - 1
2538   // biased_exp = extracted_exp + min_exp
2539   // extracted_fract = (bitcast value to uint) & (fract_mask | sign_mask)
2540   //
2541   // is_denormal = val < smallest_normalized
2542   // computed_fract = is_denormal ? scale_up : extracted_fract
2543   // computed_exp = is_denormal ? biased_exp + (-precision - 1) : biased_exp
2544   //
2545   // result_0 =  (!isfinite(val) || iszero(val)) ? val : computed_fract
2546   // result_1 =  (!isfinite(val) || iszero(val)) ? 0 : computed_exp
2547 
2548   SDValue NegSmallestNormalizedInt = DAG.getConstant(
2549       APFloat::getSmallestNormalized(FltSem, true).bitcastToAPInt(), dl,
2550       AsIntVT);
2551 
2552   SDValue SmallestNormalizedInt = DAG.getConstant(
2553       APFloat::getSmallestNormalized(FltSem, false).bitcastToAPInt(), dl,
2554       AsIntVT);
2555 
2556   // Masks out the exponent bits.
2557   SDValue ExpMask =
2558       DAG.getConstant(APFloat::getInf(FltSem).bitcastToAPInt(), dl, AsIntVT);
2559 
2560   // Mask out the exponent part of the value.
2561   //
2562   // e.g, for f32 FractSignMaskVal = 0x807fffff
2563   APInt FractSignMaskVal = APInt::getBitsSet(BitSize, 0, Precision - 1);
2564   FractSignMaskVal.setBit(BitSize - 1); // Set the sign bit
2565 
2566   APInt SignMaskVal = APInt::getSignedMaxValue(BitSize);
2567   SDValue SignMask = DAG.getConstant(SignMaskVal, dl, AsIntVT);
2568 
2569   SDValue FractSignMask = DAG.getConstant(FractSignMaskVal, dl, AsIntVT);
2570 
2571   const APFloat One(FltSem, "1.0");
2572   // Scale a possible denormal input.
2573   // e.g., for f64, 0x1p+54
2574   APFloat ScaleUpKVal =
2575       scalbn(One, Precision + 1, APFloat::rmNearestTiesToEven);
2576 
2577   SDValue ScaleUpK = DAG.getConstantFP(ScaleUpKVal, dl, VT);
2578   SDValue ScaleUp = DAG.getNode(ISD::FMUL, dl, VT, Val, ScaleUpK);
2579 
2580   EVT SetCCVT =
2581       TLI.getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
2582 
2583   SDValue AsInt = DAG.getNode(ISD::BITCAST, dl, AsIntVT, Val);
2584 
2585   SDValue Abs = DAG.getNode(ISD::AND, dl, AsIntVT, AsInt, SignMask);
2586 
2587   SDValue AddNegSmallestNormal =
2588       DAG.getNode(ISD::ADD, dl, AsIntVT, Abs, NegSmallestNormalizedInt);
2589   SDValue DenormOrZero = DAG.getSetCC(dl, SetCCVT, AddNegSmallestNormal,
2590                                       NegSmallestNormalizedInt, ISD::SETULE);
2591 
2592   SDValue IsDenormal =
2593       DAG.getSetCC(dl, SetCCVT, Abs, SmallestNormalizedInt, ISD::SETULT);
2594 
2595   SDValue MinExp = DAG.getConstant(MinExpVal, dl, ExpVT);
2596   SDValue Zero = DAG.getConstant(0, dl, ExpVT);
2597 
2598   SDValue ScaledAsInt = DAG.getNode(ISD::BITCAST, dl, AsIntVT, ScaleUp);
2599   SDValue ScaledSelect =
2600       DAG.getNode(ISD::SELECT, dl, AsIntVT, IsDenormal, ScaledAsInt, AsInt);
2601 
2602   SDValue ExpMaskScaled =
2603       DAG.getNode(ISD::AND, dl, AsIntVT, ScaledAsInt, ExpMask);
2604 
2605   SDValue ScaledValue =
2606       DAG.getNode(ISD::SELECT, dl, AsIntVT, IsDenormal, ExpMaskScaled, Abs);
2607 
2608   // Extract the exponent bits.
2609   SDValue ExponentShiftAmt =
2610       DAG.getShiftAmountConstant(Precision - 1, AsIntVT, dl);
2611   SDValue ShiftedExp =
2612       DAG.getNode(ISD::SRL, dl, AsIntVT, ScaledValue, ExponentShiftAmt);
2613   SDValue Exp = DAG.getSExtOrTrunc(ShiftedExp, dl, ExpVT);
2614 
2615   SDValue NormalBiasedExp = DAG.getNode(ISD::ADD, dl, ExpVT, Exp, MinExp);
2616   SDValue DenormalOffset = DAG.getConstant(-Precision - 1, dl, ExpVT);
2617   SDValue DenormalExpBias =
2618       DAG.getNode(ISD::SELECT, dl, ExpVT, IsDenormal, DenormalOffset, Zero);
2619 
2620   SDValue MaskedFractAsInt =
2621       DAG.getNode(ISD::AND, dl, AsIntVT, ScaledSelect, FractSignMask);
2622   const APFloat Half(FltSem, "0.5");
2623   SDValue FPHalf = DAG.getConstant(Half.bitcastToAPInt(), dl, AsIntVT);
2624   SDValue Or = DAG.getNode(ISD::OR, dl, AsIntVT, MaskedFractAsInt, FPHalf);
2625   SDValue MaskedFract = DAG.getNode(ISD::BITCAST, dl, VT, Or);
2626 
2627   SDValue ComputedExp =
2628       DAG.getNode(ISD::ADD, dl, ExpVT, NormalBiasedExp, DenormalExpBias);
2629 
2630   SDValue Result0 =
2631       DAG.getNode(ISD::SELECT, dl, VT, DenormOrZero, Val, MaskedFract);
2632 
2633   SDValue Result1 =
2634       DAG.getNode(ISD::SELECT, dl, ExpVT, DenormOrZero, Zero, ComputedExp);
2635 
2636   return DAG.getMergeValues({Result0, Result1}, dl);
2637 }
2638 
2639 /// This function is responsible for legalizing a
2640 /// INT_TO_FP operation of the specified operand when the target requests that
2641 /// we expand it.  At this point, we know that the result and operand types are
2642 /// legal for the target.
2643 SDValue SelectionDAGLegalize::ExpandLegalINT_TO_FP(SDNode *Node,
2644                                                    SDValue &Chain) {
2645   bool isSigned = (Node->getOpcode() == ISD::STRICT_SINT_TO_FP ||
2646                    Node->getOpcode() == ISD::SINT_TO_FP);
2647   EVT DestVT = Node->getValueType(0);
2648   SDLoc dl(Node);
2649   unsigned OpNo = Node->isStrictFPOpcode() ? 1 : 0;
2650   SDValue Op0 = Node->getOperand(OpNo);
2651   EVT SrcVT = Op0.getValueType();
2652 
2653   // TODO: Should any fast-math-flags be set for the created nodes?
2654   LLVM_DEBUG(dbgs() << "Legalizing INT_TO_FP\n");
2655   if (SrcVT == MVT::i32 && TLI.isTypeLegal(MVT::f64) &&
2656       (DestVT.bitsLE(MVT::f64) ||
2657        TLI.isOperationLegal(Node->isStrictFPOpcode() ? ISD::STRICT_FP_EXTEND
2658                                                      : ISD::FP_EXTEND,
2659                             DestVT))) {
2660     LLVM_DEBUG(dbgs() << "32-bit [signed|unsigned] integer to float/double "
2661                          "expansion\n");
2662 
2663     // Get the stack frame index of a 8 byte buffer.
2664     SDValue StackSlot = DAG.CreateStackTemporary(MVT::f64);
2665 
2666     SDValue Lo = Op0;
2667     // if signed map to unsigned space
2668     if (isSigned) {
2669       // Invert sign bit (signed to unsigned mapping).
2670       Lo = DAG.getNode(ISD::XOR, dl, MVT::i32, Lo,
2671                        DAG.getConstant(0x80000000u, dl, MVT::i32));
2672     }
2673     // Initial hi portion of constructed double.
2674     SDValue Hi = DAG.getConstant(0x43300000u, dl, MVT::i32);
2675 
2676     // If this a big endian target, swap the lo and high data.
2677     if (DAG.getDataLayout().isBigEndian())
2678       std::swap(Lo, Hi);
2679 
2680     SDValue MemChain = DAG.getEntryNode();
2681 
2682     // Store the lo of the constructed double.
2683     SDValue Store1 = DAG.getStore(MemChain, dl, Lo, StackSlot,
2684                                   MachinePointerInfo());
2685     // Store the hi of the constructed double.
2686     SDValue HiPtr =
2687         DAG.getMemBasePlusOffset(StackSlot, TypeSize::getFixed(4), dl);
2688     SDValue Store2 =
2689         DAG.getStore(MemChain, dl, Hi, HiPtr, MachinePointerInfo());
2690     MemChain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Store1, Store2);
2691 
2692     // load the constructed double
2693     SDValue Load =
2694         DAG.getLoad(MVT::f64, dl, MemChain, StackSlot, MachinePointerInfo());
2695     // FP constant to bias correct the final result
2696     SDValue Bias = DAG.getConstantFP(
2697         isSigned ? llvm::bit_cast<double>(0x4330000080000000ULL)
2698                  : llvm::bit_cast<double>(0x4330000000000000ULL),
2699         dl, MVT::f64);
2700     // Subtract the bias and get the final result.
2701     SDValue Sub;
2702     SDValue Result;
2703     if (Node->isStrictFPOpcode()) {
2704       Sub = DAG.getNode(ISD::STRICT_FSUB, dl, {MVT::f64, MVT::Other},
2705                         {Node->getOperand(0), Load, Bias});
2706       Chain = Sub.getValue(1);
2707       if (DestVT != Sub.getValueType()) {
2708         std::pair<SDValue, SDValue> ResultPair;
2709         ResultPair =
2710             DAG.getStrictFPExtendOrRound(Sub, Chain, dl, DestVT);
2711         Result = ResultPair.first;
2712         Chain = ResultPair.second;
2713       }
2714       else
2715         Result = Sub;
2716     } else {
2717       Sub = DAG.getNode(ISD::FSUB, dl, MVT::f64, Load, Bias);
2718       Result = DAG.getFPExtendOrRound(Sub, dl, DestVT);
2719     }
2720     return Result;
2721   }
2722 
2723   if (isSigned)
2724     return SDValue();
2725 
2726   // TODO: Generalize this for use with other types.
2727   if (((SrcVT == MVT::i32 || SrcVT == MVT::i64) && DestVT == MVT::f32) ||
2728       (SrcVT == MVT::i64 && DestVT == MVT::f64)) {
2729     LLVM_DEBUG(dbgs() << "Converting unsigned i32/i64 to f32/f64\n");
2730     // For unsigned conversions, convert them to signed conversions using the
2731     // algorithm from the x86_64 __floatundisf in compiler_rt. That method
2732     // should be valid for i32->f32 as well.
2733 
2734     // More generally this transform should be valid if there are 3 more bits
2735     // in the integer type than the significand. Rounding uses the first bit
2736     // after the width of the significand and the OR of all bits after that. So
2737     // we need to be able to OR the shifted out bit into one of the bits that
2738     // participate in the OR.
2739 
2740     // TODO: This really should be implemented using a branch rather than a
2741     // select.  We happen to get lucky and machinesink does the right
2742     // thing most of the time.  This would be a good candidate for a
2743     // pseudo-op, or, even better, for whole-function isel.
2744     EVT SetCCVT = getSetCCResultType(SrcVT);
2745 
2746     SDValue SignBitTest = DAG.getSetCC(
2747         dl, SetCCVT, Op0, DAG.getConstant(0, dl, SrcVT), ISD::SETLT);
2748 
2749     EVT ShiftVT = TLI.getShiftAmountTy(SrcVT, DAG.getDataLayout());
2750     SDValue ShiftConst = DAG.getConstant(1, dl, ShiftVT);
2751     SDValue Shr = DAG.getNode(ISD::SRL, dl, SrcVT, Op0, ShiftConst);
2752     SDValue AndConst = DAG.getConstant(1, dl, SrcVT);
2753     SDValue And = DAG.getNode(ISD::AND, dl, SrcVT, Op0, AndConst);
2754     SDValue Or = DAG.getNode(ISD::OR, dl, SrcVT, And, Shr);
2755 
2756     SDValue Slow, Fast;
2757     if (Node->isStrictFPOpcode()) {
2758       // In strict mode, we must avoid spurious exceptions, and therefore
2759       // must make sure to only emit a single STRICT_SINT_TO_FP.
2760       SDValue InCvt = DAG.getSelect(dl, SrcVT, SignBitTest, Or, Op0);
2761       Fast = DAG.getNode(ISD::STRICT_SINT_TO_FP, dl, { DestVT, MVT::Other },
2762                          { Node->getOperand(0), InCvt });
2763       Slow = DAG.getNode(ISD::STRICT_FADD, dl, { DestVT, MVT::Other },
2764                          { Fast.getValue(1), Fast, Fast });
2765       Chain = Slow.getValue(1);
2766       // The STRICT_SINT_TO_FP inherits the exception mode from the
2767       // incoming STRICT_UINT_TO_FP node; the STRICT_FADD node can
2768       // never raise any exception.
2769       SDNodeFlags Flags;
2770       Flags.setNoFPExcept(Node->getFlags().hasNoFPExcept());
2771       Fast->setFlags(Flags);
2772       Flags.setNoFPExcept(true);
2773       Slow->setFlags(Flags);
2774     } else {
2775       SDValue SignCvt = DAG.getNode(ISD::SINT_TO_FP, dl, DestVT, Or);
2776       Slow = DAG.getNode(ISD::FADD, dl, DestVT, SignCvt, SignCvt);
2777       Fast = DAG.getNode(ISD::SINT_TO_FP, dl, DestVT, Op0);
2778     }
2779 
2780     return DAG.getSelect(dl, DestVT, SignBitTest, Slow, Fast);
2781   }
2782 
2783   // Don't expand it if there isn't cheap fadd.
2784   if (!TLI.isOperationLegalOrCustom(
2785           Node->isStrictFPOpcode() ? ISD::STRICT_FADD : ISD::FADD, DestVT))
2786     return SDValue();
2787 
2788   // The following optimization is valid only if every value in SrcVT (when
2789   // treated as signed) is representable in DestVT.  Check that the mantissa
2790   // size of DestVT is >= than the number of bits in SrcVT -1.
2791   assert(APFloat::semanticsPrecision(DAG.EVTToAPFloatSemantics(DestVT)) >=
2792              SrcVT.getSizeInBits() - 1 &&
2793          "Cannot perform lossless SINT_TO_FP!");
2794 
2795   SDValue Tmp1;
2796   if (Node->isStrictFPOpcode()) {
2797     Tmp1 = DAG.getNode(ISD::STRICT_SINT_TO_FP, dl, { DestVT, MVT::Other },
2798                        { Node->getOperand(0), Op0 });
2799   } else
2800     Tmp1 = DAG.getNode(ISD::SINT_TO_FP, dl, DestVT, Op0);
2801 
2802   SDValue SignSet = DAG.getSetCC(dl, getSetCCResultType(SrcVT), Op0,
2803                                  DAG.getConstant(0, dl, SrcVT), ISD::SETLT);
2804   SDValue Zero = DAG.getIntPtrConstant(0, dl),
2805           Four = DAG.getIntPtrConstant(4, dl);
2806   SDValue CstOffset = DAG.getSelect(dl, Zero.getValueType(),
2807                                     SignSet, Four, Zero);
2808 
2809   // If the sign bit of the integer is set, the large number will be treated
2810   // as a negative number.  To counteract this, the dynamic code adds an
2811   // offset depending on the data type.
2812   uint64_t FF;
2813   switch (SrcVT.getSimpleVT().SimpleTy) {
2814   default:
2815     return SDValue();
2816   case MVT::i8 : FF = 0x43800000ULL; break;  // 2^8  (as a float)
2817   case MVT::i16: FF = 0x47800000ULL; break;  // 2^16 (as a float)
2818   case MVT::i32: FF = 0x4F800000ULL; break;  // 2^32 (as a float)
2819   case MVT::i64: FF = 0x5F800000ULL; break;  // 2^64 (as a float)
2820   }
2821   if (DAG.getDataLayout().isLittleEndian())
2822     FF <<= 32;
2823   Constant *FudgeFactor = ConstantInt::get(
2824                                        Type::getInt64Ty(*DAG.getContext()), FF);
2825 
2826   SDValue CPIdx =
2827       DAG.getConstantPool(FudgeFactor, TLI.getPointerTy(DAG.getDataLayout()));
2828   Align Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlign();
2829   CPIdx = DAG.getNode(ISD::ADD, dl, CPIdx.getValueType(), CPIdx, CstOffset);
2830   Alignment = commonAlignment(Alignment, 4);
2831   SDValue FudgeInReg;
2832   if (DestVT == MVT::f32)
2833     FudgeInReg = DAG.getLoad(
2834         MVT::f32, dl, DAG.getEntryNode(), CPIdx,
2835         MachinePointerInfo::getConstantPool(DAG.getMachineFunction()),
2836         Alignment);
2837   else {
2838     SDValue Load = DAG.getExtLoad(
2839         ISD::EXTLOAD, dl, DestVT, DAG.getEntryNode(), CPIdx,
2840         MachinePointerInfo::getConstantPool(DAG.getMachineFunction()), MVT::f32,
2841         Alignment);
2842     HandleSDNode Handle(Load);
2843     LegalizeOp(Load.getNode());
2844     FudgeInReg = Handle.getValue();
2845   }
2846 
2847   if (Node->isStrictFPOpcode()) {
2848     SDValue Result = DAG.getNode(ISD::STRICT_FADD, dl, { DestVT, MVT::Other },
2849                                  { Tmp1.getValue(1), Tmp1, FudgeInReg });
2850     Chain = Result.getValue(1);
2851     return Result;
2852   }
2853 
2854   return DAG.getNode(ISD::FADD, dl, DestVT, Tmp1, FudgeInReg);
2855 }
2856 
2857 /// This function is responsible for legalizing a
2858 /// *INT_TO_FP operation of the specified operand when the target requests that
2859 /// we promote it.  At this point, we know that the result and operand types are
2860 /// legal for the target, and that there is a legal UINT_TO_FP or SINT_TO_FP
2861 /// operation that takes a larger input.
2862 void SelectionDAGLegalize::PromoteLegalINT_TO_FP(
2863     SDNode *N, const SDLoc &dl, SmallVectorImpl<SDValue> &Results) {
2864   bool IsStrict = N->isStrictFPOpcode();
2865   bool IsSigned = N->getOpcode() == ISD::SINT_TO_FP ||
2866                   N->getOpcode() == ISD::STRICT_SINT_TO_FP;
2867   EVT DestVT = N->getValueType(0);
2868   SDValue LegalOp = N->getOperand(IsStrict ? 1 : 0);
2869   unsigned UIntOp = IsStrict ? ISD::STRICT_UINT_TO_FP : ISD::UINT_TO_FP;
2870   unsigned SIntOp = IsStrict ? ISD::STRICT_SINT_TO_FP : ISD::SINT_TO_FP;
2871 
2872   // First step, figure out the appropriate *INT_TO_FP operation to use.
2873   EVT NewInTy = LegalOp.getValueType();
2874 
2875   unsigned OpToUse = 0;
2876 
2877   // Scan for the appropriate larger type to use.
2878   while (true) {
2879     NewInTy = (MVT::SimpleValueType)(NewInTy.getSimpleVT().SimpleTy+1);
2880     assert(NewInTy.isInteger() && "Ran out of possibilities!");
2881 
2882     // If the target supports SINT_TO_FP of this type, use it.
2883     if (TLI.isOperationLegalOrCustom(SIntOp, NewInTy)) {
2884       OpToUse = SIntOp;
2885       break;
2886     }
2887     if (IsSigned)
2888       continue;
2889 
2890     // If the target supports UINT_TO_FP of this type, use it.
2891     if (TLI.isOperationLegalOrCustom(UIntOp, NewInTy)) {
2892       OpToUse = UIntOp;
2893       break;
2894     }
2895 
2896     // Otherwise, try a larger type.
2897   }
2898 
2899   // Okay, we found the operation and type to use.  Zero extend our input to the
2900   // desired type then run the operation on it.
2901   if (IsStrict) {
2902     SDValue Res =
2903         DAG.getNode(OpToUse, dl, {DestVT, MVT::Other},
2904                     {N->getOperand(0),
2905                      DAG.getNode(IsSigned ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND,
2906                                  dl, NewInTy, LegalOp)});
2907     Results.push_back(Res);
2908     Results.push_back(Res.getValue(1));
2909     return;
2910   }
2911 
2912   Results.push_back(
2913       DAG.getNode(OpToUse, dl, DestVT,
2914                   DAG.getNode(IsSigned ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND,
2915                               dl, NewInTy, LegalOp)));
2916 }
2917 
2918 /// This function is responsible for legalizing a
2919 /// FP_TO_*INT operation of the specified operand when the target requests that
2920 /// we promote it.  At this point, we know that the result and operand types are
2921 /// legal for the target, and that there is a legal FP_TO_UINT or FP_TO_SINT
2922 /// operation that returns a larger result.
2923 void SelectionDAGLegalize::PromoteLegalFP_TO_INT(SDNode *N, const SDLoc &dl,
2924                                                  SmallVectorImpl<SDValue> &Results) {
2925   bool IsStrict = N->isStrictFPOpcode();
2926   bool IsSigned = N->getOpcode() == ISD::FP_TO_SINT ||
2927                   N->getOpcode() == ISD::STRICT_FP_TO_SINT;
2928   EVT DestVT = N->getValueType(0);
2929   SDValue LegalOp = N->getOperand(IsStrict ? 1 : 0);
2930   // First step, figure out the appropriate FP_TO*INT operation to use.
2931   EVT NewOutTy = DestVT;
2932 
2933   unsigned OpToUse = 0;
2934 
2935   // Scan for the appropriate larger type to use.
2936   while (true) {
2937     NewOutTy = (MVT::SimpleValueType)(NewOutTy.getSimpleVT().SimpleTy+1);
2938     assert(NewOutTy.isInteger() && "Ran out of possibilities!");
2939 
2940     // A larger signed type can hold all unsigned values of the requested type,
2941     // so using FP_TO_SINT is valid
2942     OpToUse = IsStrict ? ISD::STRICT_FP_TO_SINT : ISD::FP_TO_SINT;
2943     if (TLI.isOperationLegalOrCustom(OpToUse, NewOutTy))
2944       break;
2945 
2946     // However, if the value may be < 0.0, we *must* use some FP_TO_SINT.
2947     OpToUse = IsStrict ? ISD::STRICT_FP_TO_UINT : ISD::FP_TO_UINT;
2948     if (!IsSigned && TLI.isOperationLegalOrCustom(OpToUse, NewOutTy))
2949       break;
2950 
2951     // Otherwise, try a larger type.
2952   }
2953 
2954   // Okay, we found the operation and type to use.
2955   SDValue Operation;
2956   if (IsStrict) {
2957     SDVTList VTs = DAG.getVTList(NewOutTy, MVT::Other);
2958     Operation = DAG.getNode(OpToUse, dl, VTs, N->getOperand(0), LegalOp);
2959   } else
2960     Operation = DAG.getNode(OpToUse, dl, NewOutTy, LegalOp);
2961 
2962   // Truncate the result of the extended FP_TO_*INT operation to the desired
2963   // size.
2964   SDValue Trunc = DAG.getNode(ISD::TRUNCATE, dl, DestVT, Operation);
2965   Results.push_back(Trunc);
2966   if (IsStrict)
2967     Results.push_back(Operation.getValue(1));
2968 }
2969 
2970 /// Promote FP_TO_*INT_SAT operation to a larger result type. At this point
2971 /// the result and operand types are legal and there must be a legal
2972 /// FP_TO_*INT_SAT operation for a larger result type.
2973 SDValue SelectionDAGLegalize::PromoteLegalFP_TO_INT_SAT(SDNode *Node,
2974                                                         const SDLoc &dl) {
2975   unsigned Opcode = Node->getOpcode();
2976 
2977   // Scan for the appropriate larger type to use.
2978   EVT NewOutTy = Node->getValueType(0);
2979   while (true) {
2980     NewOutTy = (MVT::SimpleValueType)(NewOutTy.getSimpleVT().SimpleTy + 1);
2981     assert(NewOutTy.isInteger() && "Ran out of possibilities!");
2982 
2983     if (TLI.isOperationLegalOrCustom(Opcode, NewOutTy))
2984       break;
2985   }
2986 
2987   // Saturation width is determined by second operand, so we don't have to
2988   // perform any fixup and can directly truncate the result.
2989   SDValue Result = DAG.getNode(Opcode, dl, NewOutTy, Node->getOperand(0),
2990                                Node->getOperand(1));
2991   return DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0), Result);
2992 }
2993 
2994 /// Open code the operations for PARITY of the specified operation.
2995 SDValue SelectionDAGLegalize::ExpandPARITY(SDValue Op, const SDLoc &dl) {
2996   EVT VT = Op.getValueType();
2997   EVT ShVT = TLI.getShiftAmountTy(VT, DAG.getDataLayout());
2998   unsigned Sz = VT.getScalarSizeInBits();
2999 
3000   // If CTPOP is legal, use it. Otherwise use shifts and xor.
3001   SDValue Result;
3002   if (TLI.isOperationLegalOrPromote(ISD::CTPOP, VT)) {
3003     Result = DAG.getNode(ISD::CTPOP, dl, VT, Op);
3004   } else {
3005     Result = Op;
3006     for (unsigned i = Log2_32_Ceil(Sz); i != 0;) {
3007       SDValue Shift = DAG.getNode(ISD::SRL, dl, VT, Result,
3008                                   DAG.getConstant(1ULL << (--i), dl, ShVT));
3009       Result = DAG.getNode(ISD::XOR, dl, VT, Result, Shift);
3010     }
3011   }
3012 
3013   return DAG.getNode(ISD::AND, dl, VT, Result, DAG.getConstant(1, dl, VT));
3014 }
3015 
3016 SDValue SelectionDAGLegalize::PromoteReduction(SDNode *Node) {
3017   MVT VecVT = Node->getOperand(1).getSimpleValueType();
3018   MVT NewVecVT = TLI.getTypeToPromoteTo(Node->getOpcode(), VecVT);
3019   MVT ScalarVT = Node->getSimpleValueType(0);
3020   MVT NewScalarVT = NewVecVT.getVectorElementType();
3021 
3022   SDLoc DL(Node);
3023   SmallVector<SDValue, 4> Operands(Node->getNumOperands());
3024 
3025   // promote the initial value.
3026   // FIXME: Support integer.
3027   assert(Node->getOperand(0).getValueType().isFloatingPoint() &&
3028          "Only FP promotion is supported");
3029   Operands[0] =
3030       DAG.getNode(ISD::FP_EXTEND, DL, NewScalarVT, Node->getOperand(0));
3031 
3032   for (unsigned j = 1; j != Node->getNumOperands(); ++j)
3033     if (Node->getOperand(j).getValueType().isVector() &&
3034         !(ISD::isVPOpcode(Node->getOpcode()) &&
3035           ISD::getVPMaskIdx(Node->getOpcode()) == j)) { // Skip mask operand.
3036       // promote the vector operand.
3037       // FIXME: Support integer.
3038       assert(Node->getOperand(j).getValueType().isFloatingPoint() &&
3039              "Only FP promotion is supported");
3040       Operands[j] =
3041           DAG.getNode(ISD::FP_EXTEND, DL, NewVecVT, Node->getOperand(j));
3042     } else {
3043       Operands[j] = Node->getOperand(j); // Skip VL operand.
3044     }
3045 
3046   SDValue Res = DAG.getNode(Node->getOpcode(), DL, NewScalarVT, Operands,
3047                             Node->getFlags());
3048 
3049   assert(ScalarVT.isFloatingPoint() && "Only FP promotion is supported");
3050   return DAG.getNode(ISD::FP_ROUND, DL, ScalarVT, Res,
3051                      DAG.getIntPtrConstant(0, DL, /*isTarget=*/true));
3052 }
3053 
3054 bool SelectionDAGLegalize::ExpandNode(SDNode *Node) {
3055   LLVM_DEBUG(dbgs() << "Trying to expand node\n");
3056   SmallVector<SDValue, 8> Results;
3057   SDLoc dl(Node);
3058   SDValue Tmp1, Tmp2, Tmp3, Tmp4;
3059   bool NeedInvert;
3060   switch (Node->getOpcode()) {
3061   case ISD::ABS:
3062     if ((Tmp1 = TLI.expandABS(Node, DAG)))
3063       Results.push_back(Tmp1);
3064     break;
3065   case ISD::ABDS:
3066   case ISD::ABDU:
3067     if ((Tmp1 = TLI.expandABD(Node, DAG)))
3068       Results.push_back(Tmp1);
3069     break;
3070   case ISD::AVGCEILS:
3071   case ISD::AVGCEILU:
3072   case ISD::AVGFLOORS:
3073   case ISD::AVGFLOORU:
3074     if ((Tmp1 = TLI.expandAVG(Node, DAG)))
3075       Results.push_back(Tmp1);
3076     break;
3077   case ISD::CTPOP:
3078     if ((Tmp1 = TLI.expandCTPOP(Node, DAG)))
3079       Results.push_back(Tmp1);
3080     break;
3081   case ISD::CTLZ:
3082   case ISD::CTLZ_ZERO_UNDEF:
3083     if ((Tmp1 = TLI.expandCTLZ(Node, DAG)))
3084       Results.push_back(Tmp1);
3085     break;
3086   case ISD::CTTZ:
3087   case ISD::CTTZ_ZERO_UNDEF:
3088     if ((Tmp1 = TLI.expandCTTZ(Node, DAG)))
3089       Results.push_back(Tmp1);
3090     break;
3091   case ISD::BITREVERSE:
3092     if ((Tmp1 = TLI.expandBITREVERSE(Node, DAG)))
3093       Results.push_back(Tmp1);
3094     break;
3095   case ISD::BSWAP:
3096     if ((Tmp1 = TLI.expandBSWAP(Node, DAG)))
3097       Results.push_back(Tmp1);
3098     break;
3099   case ISD::PARITY:
3100     Results.push_back(ExpandPARITY(Node->getOperand(0), dl));
3101     break;
3102   case ISD::FRAMEADDR:
3103   case ISD::RETURNADDR:
3104   case ISD::FRAME_TO_ARGS_OFFSET:
3105     Results.push_back(DAG.getConstant(0, dl, Node->getValueType(0)));
3106     break;
3107   case ISD::EH_DWARF_CFA: {
3108     SDValue CfaArg = DAG.getSExtOrTrunc(Node->getOperand(0), dl,
3109                                         TLI.getPointerTy(DAG.getDataLayout()));
3110     SDValue Offset = DAG.getNode(ISD::ADD, dl,
3111                                  CfaArg.getValueType(),
3112                                  DAG.getNode(ISD::FRAME_TO_ARGS_OFFSET, dl,
3113                                              CfaArg.getValueType()),
3114                                  CfaArg);
3115     SDValue FA = DAG.getNode(
3116         ISD::FRAMEADDR, dl, TLI.getPointerTy(DAG.getDataLayout()),
3117         DAG.getConstant(0, dl, TLI.getPointerTy(DAG.getDataLayout())));
3118     Results.push_back(DAG.getNode(ISD::ADD, dl, FA.getValueType(),
3119                                   FA, Offset));
3120     break;
3121   }
3122   case ISD::GET_ROUNDING:
3123     Results.push_back(DAG.getConstant(1, dl, Node->getValueType(0)));
3124     Results.push_back(Node->getOperand(0));
3125     break;
3126   case ISD::EH_RETURN:
3127   case ISD::EH_LABEL:
3128   case ISD::PREFETCH:
3129   case ISD::VAEND:
3130   case ISD::EH_SJLJ_LONGJMP:
3131     // If the target didn't expand these, there's nothing to do, so just
3132     // preserve the chain and be done.
3133     Results.push_back(Node->getOperand(0));
3134     break;
3135   case ISD::READCYCLECOUNTER:
3136   case ISD::READSTEADYCOUNTER:
3137     // If the target didn't expand this, just return 'zero' and preserve the
3138     // chain.
3139     Results.append(Node->getNumValues() - 1,
3140                    DAG.getConstant(0, dl, Node->getValueType(0)));
3141     Results.push_back(Node->getOperand(0));
3142     break;
3143   case ISD::EH_SJLJ_SETJMP:
3144     // If the target didn't expand this, just return 'zero' and preserve the
3145     // chain.
3146     Results.push_back(DAG.getConstant(0, dl, MVT::i32));
3147     Results.push_back(Node->getOperand(0));
3148     break;
3149   case ISD::ATOMIC_LOAD: {
3150     // There is no libcall for atomic load; fake it with ATOMIC_CMP_SWAP.
3151     SDValue Zero = DAG.getConstant(0, dl, Node->getValueType(0));
3152     SDVTList VTs = DAG.getVTList(Node->getValueType(0), MVT::Other);
3153     SDValue Swap = DAG.getAtomicCmpSwap(
3154         ISD::ATOMIC_CMP_SWAP, dl, cast<AtomicSDNode>(Node)->getMemoryVT(), VTs,
3155         Node->getOperand(0), Node->getOperand(1), Zero, Zero,
3156         cast<AtomicSDNode>(Node)->getMemOperand());
3157     Results.push_back(Swap.getValue(0));
3158     Results.push_back(Swap.getValue(1));
3159     break;
3160   }
3161   case ISD::ATOMIC_STORE: {
3162     // There is no libcall for atomic store; fake it with ATOMIC_SWAP.
3163     SDValue Swap = DAG.getAtomic(
3164         ISD::ATOMIC_SWAP, dl, cast<AtomicSDNode>(Node)->getMemoryVT(),
3165         Node->getOperand(0), Node->getOperand(2), Node->getOperand(1),
3166         cast<AtomicSDNode>(Node)->getMemOperand());
3167     Results.push_back(Swap.getValue(1));
3168     break;
3169   }
3170   case ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS: {
3171     // Expanding an ATOMIC_CMP_SWAP_WITH_SUCCESS produces an ATOMIC_CMP_SWAP and
3172     // splits out the success value as a comparison. Expanding the resulting
3173     // ATOMIC_CMP_SWAP will produce a libcall.
3174     SDVTList VTs = DAG.getVTList(Node->getValueType(0), MVT::Other);
3175     SDValue Res = DAG.getAtomicCmpSwap(
3176         ISD::ATOMIC_CMP_SWAP, dl, cast<AtomicSDNode>(Node)->getMemoryVT(), VTs,
3177         Node->getOperand(0), Node->getOperand(1), Node->getOperand(2),
3178         Node->getOperand(3), cast<MemSDNode>(Node)->getMemOperand());
3179 
3180     SDValue ExtRes = Res;
3181     SDValue LHS = Res;
3182     SDValue RHS = Node->getOperand(1);
3183 
3184     EVT AtomicType = cast<AtomicSDNode>(Node)->getMemoryVT();
3185     EVT OuterType = Node->getValueType(0);
3186     switch (TLI.getExtendForAtomicOps()) {
3187     case ISD::SIGN_EXTEND:
3188       LHS = DAG.getNode(ISD::AssertSext, dl, OuterType, Res,
3189                         DAG.getValueType(AtomicType));
3190       RHS = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl, OuterType,
3191                         Node->getOperand(2), DAG.getValueType(AtomicType));
3192       ExtRes = LHS;
3193       break;
3194     case ISD::ZERO_EXTEND:
3195       LHS = DAG.getNode(ISD::AssertZext, dl, OuterType, Res,
3196                         DAG.getValueType(AtomicType));
3197       RHS = DAG.getZeroExtendInReg(Node->getOperand(2), dl, AtomicType);
3198       ExtRes = LHS;
3199       break;
3200     case ISD::ANY_EXTEND:
3201       LHS = DAG.getZeroExtendInReg(Res, dl, AtomicType);
3202       RHS = DAG.getZeroExtendInReg(Node->getOperand(2), dl, AtomicType);
3203       break;
3204     default:
3205       llvm_unreachable("Invalid atomic op extension");
3206     }
3207 
3208     SDValue Success =
3209         DAG.getSetCC(dl, Node->getValueType(1), LHS, RHS, ISD::SETEQ);
3210 
3211     Results.push_back(ExtRes.getValue(0));
3212     Results.push_back(Success);
3213     Results.push_back(Res.getValue(1));
3214     break;
3215   }
3216   case ISD::ATOMIC_LOAD_SUB: {
3217     SDLoc DL(Node);
3218     EVT VT = Node->getValueType(0);
3219     SDValue RHS = Node->getOperand(2);
3220     AtomicSDNode *AN = cast<AtomicSDNode>(Node);
3221     if (RHS->getOpcode() == ISD::SIGN_EXTEND_INREG &&
3222         cast<VTSDNode>(RHS->getOperand(1))->getVT() == AN->getMemoryVT())
3223       RHS = RHS->getOperand(0);
3224     SDValue NewRHS =
3225         DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT), RHS);
3226     SDValue Res = DAG.getAtomic(ISD::ATOMIC_LOAD_ADD, DL, AN->getMemoryVT(),
3227                                 Node->getOperand(0), Node->getOperand(1),
3228                                 NewRHS, AN->getMemOperand());
3229     Results.push_back(Res);
3230     Results.push_back(Res.getValue(1));
3231     break;
3232   }
3233   case ISD::DYNAMIC_STACKALLOC:
3234     ExpandDYNAMIC_STACKALLOC(Node, Results);
3235     break;
3236   case ISD::MERGE_VALUES:
3237     for (unsigned i = 0; i < Node->getNumValues(); i++)
3238       Results.push_back(Node->getOperand(i));
3239     break;
3240   case ISD::UNDEF: {
3241     EVT VT = Node->getValueType(0);
3242     if (VT.isInteger())
3243       Results.push_back(DAG.getConstant(0, dl, VT));
3244     else {
3245       assert(VT.isFloatingPoint() && "Unknown value type!");
3246       Results.push_back(DAG.getConstantFP(0, dl, VT));
3247     }
3248     break;
3249   }
3250   case ISD::STRICT_FP_ROUND:
3251     // When strict mode is enforced we can't do expansion because it
3252     // does not honor the "strict" properties. Only libcall is allowed.
3253     if (TLI.isStrictFPEnabled())
3254       break;
3255     // We might as well mutate to FP_ROUND when FP_ROUND operation is legal
3256     // since this operation is more efficient than stack operation.
3257     if (TLI.getStrictFPOperationAction(Node->getOpcode(),
3258                                        Node->getValueType(0))
3259         == TargetLowering::Legal)
3260       break;
3261     // We fall back to use stack operation when the FP_ROUND operation
3262     // isn't available.
3263     if ((Tmp1 = EmitStackConvert(Node->getOperand(1), Node->getValueType(0),
3264                                  Node->getValueType(0), dl,
3265                                  Node->getOperand(0)))) {
3266       ReplaceNode(Node, Tmp1.getNode());
3267       LLVM_DEBUG(dbgs() << "Successfully expanded STRICT_FP_ROUND node\n");
3268       return true;
3269     }
3270     break;
3271   case ISD::FP_ROUND: {
3272     if ((Tmp1 = TLI.expandFP_ROUND(Node, DAG))) {
3273       Results.push_back(Tmp1);
3274       break;
3275     }
3276 
3277     [[fallthrough]];
3278   }
3279   case ISD::BITCAST:
3280     if ((Tmp1 = EmitStackConvert(Node->getOperand(0), Node->getValueType(0),
3281                                  Node->getValueType(0), dl)))
3282       Results.push_back(Tmp1);
3283     break;
3284   case ISD::STRICT_FP_EXTEND:
3285     // When strict mode is enforced we can't do expansion because it
3286     // does not honor the "strict" properties. Only libcall is allowed.
3287     if (TLI.isStrictFPEnabled())
3288       break;
3289     // We might as well mutate to FP_EXTEND when FP_EXTEND operation is legal
3290     // since this operation is more efficient than stack operation.
3291     if (TLI.getStrictFPOperationAction(Node->getOpcode(),
3292                                        Node->getValueType(0))
3293         == TargetLowering::Legal)
3294       break;
3295     // We fall back to use stack operation when the FP_EXTEND operation
3296     // isn't available.
3297     if ((Tmp1 = EmitStackConvert(
3298              Node->getOperand(1), Node->getOperand(1).getValueType(),
3299              Node->getValueType(0), dl, Node->getOperand(0)))) {
3300       ReplaceNode(Node, Tmp1.getNode());
3301       LLVM_DEBUG(dbgs() << "Successfully expanded STRICT_FP_EXTEND node\n");
3302       return true;
3303     }
3304     break;
3305   case ISD::FP_EXTEND: {
3306     SDValue Op = Node->getOperand(0);
3307     EVT SrcVT = Op.getValueType();
3308     EVT DstVT = Node->getValueType(0);
3309     if (SrcVT.getScalarType() == MVT::bf16) {
3310       Results.push_back(DAG.getNode(ISD::BF16_TO_FP, SDLoc(Node), DstVT, Op));
3311       break;
3312     }
3313 
3314     if ((Tmp1 = EmitStackConvert(Op, SrcVT, DstVT, dl)))
3315       Results.push_back(Tmp1);
3316     break;
3317   }
3318   case ISD::BF16_TO_FP: {
3319     // Always expand bf16 to f32 casts, they lower to ext + shift.
3320     //
3321     // Note that the operand of this code can be bf16 or an integer type in case
3322     // bf16 is not supported on the target and was softened.
3323     SDValue Op = Node->getOperand(0);
3324     if (Op.getValueType() == MVT::bf16) {
3325       Op = DAG.getNode(ISD::ANY_EXTEND, dl, MVT::i32,
3326                        DAG.getNode(ISD::BITCAST, dl, MVT::i16, Op));
3327     } else {
3328       Op = DAG.getAnyExtOrTrunc(Op, dl, MVT::i32);
3329     }
3330     Op = DAG.getNode(
3331         ISD::SHL, dl, MVT::i32, Op,
3332         DAG.getConstant(16, dl,
3333                         TLI.getShiftAmountTy(MVT::i32, DAG.getDataLayout())));
3334     Op = DAG.getNode(ISD::BITCAST, dl, MVT::f32, Op);
3335     // Add fp_extend in case the output is bigger than f32.
3336     if (Node->getValueType(0) != MVT::f32)
3337       Op = DAG.getNode(ISD::FP_EXTEND, dl, Node->getValueType(0), Op);
3338     Results.push_back(Op);
3339     break;
3340   }
3341   case ISD::FP_TO_BF16: {
3342     SDValue Op = Node->getOperand(0);
3343     if (Op.getValueType() != MVT::f32)
3344       Op = DAG.getNode(ISD::FP_ROUND, dl, MVT::f32, Op,
3345                        DAG.getIntPtrConstant(0, dl, /*isTarget=*/true));
3346     // Certain SNaNs will turn into infinities if we do a simple shift right.
3347     if (!DAG.isKnownNeverSNaN(Op)) {
3348       Op = DAG.getNode(ISD::FCANONICALIZE, dl, MVT::f32, Op, Node->getFlags());
3349     }
3350     Op = DAG.getNode(
3351         ISD::SRL, dl, MVT::i32, DAG.getNode(ISD::BITCAST, dl, MVT::i32, Op),
3352         DAG.getConstant(16, dl,
3353                         TLI.getShiftAmountTy(MVT::i32, DAG.getDataLayout())));
3354     // The result of this node can be bf16 or an integer type in case bf16 is
3355     // not supported on the target and was softened to i16 for storage.
3356     if (Node->getValueType(0) == MVT::bf16) {
3357       Op = DAG.getNode(ISD::BITCAST, dl, MVT::bf16,
3358                        DAG.getNode(ISD::TRUNCATE, dl, MVT::i16, Op));
3359     } else {
3360       Op = DAG.getAnyExtOrTrunc(Op, dl, Node->getValueType(0));
3361     }
3362     Results.push_back(Op);
3363     break;
3364   }
3365   case ISD::SIGN_EXTEND_INREG: {
3366     EVT ExtraVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
3367     EVT VT = Node->getValueType(0);
3368 
3369     // An in-register sign-extend of a boolean is a negation:
3370     // 'true' (1) sign-extended is -1.
3371     // 'false' (0) sign-extended is 0.
3372     // However, we must mask the high bits of the source operand because the
3373     // SIGN_EXTEND_INREG does not guarantee that the high bits are already zero.
3374 
3375     // TODO: Do this for vectors too?
3376     if (ExtraVT.isScalarInteger() && ExtraVT.getSizeInBits() == 1) {
3377       SDValue One = DAG.getConstant(1, dl, VT);
3378       SDValue And = DAG.getNode(ISD::AND, dl, VT, Node->getOperand(0), One);
3379       SDValue Zero = DAG.getConstant(0, dl, VT);
3380       SDValue Neg = DAG.getNode(ISD::SUB, dl, VT, Zero, And);
3381       Results.push_back(Neg);
3382       break;
3383     }
3384 
3385     // NOTE: we could fall back on load/store here too for targets without
3386     // SRA.  However, it is doubtful that any exist.
3387     EVT ShiftAmountTy = TLI.getShiftAmountTy(VT, DAG.getDataLayout());
3388     unsigned BitsDiff = VT.getScalarSizeInBits() -
3389                         ExtraVT.getScalarSizeInBits();
3390     SDValue ShiftCst = DAG.getConstant(BitsDiff, dl, ShiftAmountTy);
3391     Tmp1 = DAG.getNode(ISD::SHL, dl, Node->getValueType(0),
3392                        Node->getOperand(0), ShiftCst);
3393     Tmp1 = DAG.getNode(ISD::SRA, dl, Node->getValueType(0), Tmp1, ShiftCst);
3394     Results.push_back(Tmp1);
3395     break;
3396   }
3397   case ISD::UINT_TO_FP:
3398   case ISD::STRICT_UINT_TO_FP:
3399     if (TLI.expandUINT_TO_FP(Node, Tmp1, Tmp2, DAG)) {
3400       Results.push_back(Tmp1);
3401       if (Node->isStrictFPOpcode())
3402         Results.push_back(Tmp2);
3403       break;
3404     }
3405     [[fallthrough]];
3406   case ISD::SINT_TO_FP:
3407   case ISD::STRICT_SINT_TO_FP:
3408     if ((Tmp1 = ExpandLegalINT_TO_FP(Node, Tmp2))) {
3409       Results.push_back(Tmp1);
3410       if (Node->isStrictFPOpcode())
3411         Results.push_back(Tmp2);
3412     }
3413     break;
3414   case ISD::FP_TO_SINT:
3415     if (TLI.expandFP_TO_SINT(Node, Tmp1, DAG))
3416       Results.push_back(Tmp1);
3417     break;
3418   case ISD::STRICT_FP_TO_SINT:
3419     if (TLI.expandFP_TO_SINT(Node, Tmp1, DAG)) {
3420       ReplaceNode(Node, Tmp1.getNode());
3421       LLVM_DEBUG(dbgs() << "Successfully expanded STRICT_FP_TO_SINT node\n");
3422       return true;
3423     }
3424     break;
3425   case ISD::FP_TO_UINT:
3426     if (TLI.expandFP_TO_UINT(Node, Tmp1, Tmp2, DAG))
3427       Results.push_back(Tmp1);
3428     break;
3429   case ISD::STRICT_FP_TO_UINT:
3430     if (TLI.expandFP_TO_UINT(Node, Tmp1, Tmp2, DAG)) {
3431       // Relink the chain.
3432       DAG.ReplaceAllUsesOfValueWith(SDValue(Node,1), Tmp2);
3433       // Replace the new UINT result.
3434       ReplaceNodeWithValue(SDValue(Node, 0), Tmp1);
3435       LLVM_DEBUG(dbgs() << "Successfully expanded STRICT_FP_TO_UINT node\n");
3436       return true;
3437     }
3438     break;
3439   case ISD::FP_TO_SINT_SAT:
3440   case ISD::FP_TO_UINT_SAT:
3441     Results.push_back(TLI.expandFP_TO_INT_SAT(Node, DAG));
3442     break;
3443   case ISD::VAARG:
3444     Results.push_back(DAG.expandVAArg(Node));
3445     Results.push_back(Results[0].getValue(1));
3446     break;
3447   case ISD::VACOPY:
3448     Results.push_back(DAG.expandVACopy(Node));
3449     break;
3450   case ISD::EXTRACT_VECTOR_ELT:
3451     if (Node->getOperand(0).getValueType().getVectorElementCount().isScalar())
3452       // This must be an access of the only element.  Return it.
3453       Tmp1 = DAG.getNode(ISD::BITCAST, dl, Node->getValueType(0),
3454                          Node->getOperand(0));
3455     else
3456       Tmp1 = ExpandExtractFromVectorThroughStack(SDValue(Node, 0));
3457     Results.push_back(Tmp1);
3458     break;
3459   case ISD::EXTRACT_SUBVECTOR:
3460     Results.push_back(ExpandExtractFromVectorThroughStack(SDValue(Node, 0)));
3461     break;
3462   case ISD::INSERT_SUBVECTOR:
3463     Results.push_back(ExpandInsertToVectorThroughStack(SDValue(Node, 0)));
3464     break;
3465   case ISD::CONCAT_VECTORS:
3466     Results.push_back(ExpandVectorBuildThroughStack(Node));
3467     break;
3468   case ISD::SCALAR_TO_VECTOR:
3469     Results.push_back(ExpandSCALAR_TO_VECTOR(Node));
3470     break;
3471   case ISD::INSERT_VECTOR_ELT:
3472     Results.push_back(ExpandINSERT_VECTOR_ELT(SDValue(Node, 0)));
3473     break;
3474   case ISD::VECTOR_SHUFFLE: {
3475     SmallVector<int, 32> NewMask;
3476     ArrayRef<int> Mask = cast<ShuffleVectorSDNode>(Node)->getMask();
3477 
3478     EVT VT = Node->getValueType(0);
3479     EVT EltVT = VT.getVectorElementType();
3480     SDValue Op0 = Node->getOperand(0);
3481     SDValue Op1 = Node->getOperand(1);
3482     if (!TLI.isTypeLegal(EltVT)) {
3483       EVT NewEltVT = TLI.getTypeToTransformTo(*DAG.getContext(), EltVT);
3484 
3485       // BUILD_VECTOR operands are allowed to be wider than the element type.
3486       // But if NewEltVT is smaller that EltVT the BUILD_VECTOR does not accept
3487       // it.
3488       if (NewEltVT.bitsLT(EltVT)) {
3489         // Convert shuffle node.
3490         // If original node was v4i64 and the new EltVT is i32,
3491         // cast operands to v8i32 and re-build the mask.
3492 
3493         // Calculate new VT, the size of the new VT should be equal to original.
3494         EVT NewVT =
3495             EVT::getVectorVT(*DAG.getContext(), NewEltVT,
3496                              VT.getSizeInBits() / NewEltVT.getSizeInBits());
3497         assert(NewVT.bitsEq(VT));
3498 
3499         // cast operands to new VT
3500         Op0 = DAG.getNode(ISD::BITCAST, dl, NewVT, Op0);
3501         Op1 = DAG.getNode(ISD::BITCAST, dl, NewVT, Op1);
3502 
3503         // Convert the shuffle mask
3504         unsigned int factor =
3505                          NewVT.getVectorNumElements()/VT.getVectorNumElements();
3506 
3507         // EltVT gets smaller
3508         assert(factor > 0);
3509 
3510         for (unsigned i = 0; i < VT.getVectorNumElements(); ++i) {
3511           if (Mask[i] < 0) {
3512             for (unsigned fi = 0; fi < factor; ++fi)
3513               NewMask.push_back(Mask[i]);
3514           }
3515           else {
3516             for (unsigned fi = 0; fi < factor; ++fi)
3517               NewMask.push_back(Mask[i]*factor+fi);
3518           }
3519         }
3520         Mask = NewMask;
3521         VT = NewVT;
3522       }
3523       EltVT = NewEltVT;
3524     }
3525     unsigned NumElems = VT.getVectorNumElements();
3526     SmallVector<SDValue, 16> Ops;
3527     for (unsigned i = 0; i != NumElems; ++i) {
3528       if (Mask[i] < 0) {
3529         Ops.push_back(DAG.getUNDEF(EltVT));
3530         continue;
3531       }
3532       unsigned Idx = Mask[i];
3533       if (Idx < NumElems)
3534         Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT, Op0,
3535                                   DAG.getVectorIdxConstant(Idx, dl)));
3536       else
3537         Ops.push_back(
3538             DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT, Op1,
3539                         DAG.getVectorIdxConstant(Idx - NumElems, dl)));
3540     }
3541 
3542     Tmp1 = DAG.getBuildVector(VT, dl, Ops);
3543     // We may have changed the BUILD_VECTOR type. Cast it back to the Node type.
3544     Tmp1 = DAG.getNode(ISD::BITCAST, dl, Node->getValueType(0), Tmp1);
3545     Results.push_back(Tmp1);
3546     break;
3547   }
3548   case ISD::VECTOR_SPLICE: {
3549     Results.push_back(TLI.expandVectorSplice(Node, DAG));
3550     break;
3551   }
3552   case ISD::EXTRACT_ELEMENT: {
3553     EVT OpTy = Node->getOperand(0).getValueType();
3554     if (Node->getConstantOperandVal(1)) {
3555       // 1 -> Hi
3556       Tmp1 = DAG.getNode(ISD::SRL, dl, OpTy, Node->getOperand(0),
3557                          DAG.getConstant(OpTy.getSizeInBits() / 2, dl,
3558                                          TLI.getShiftAmountTy(
3559                                              Node->getOperand(0).getValueType(),
3560                                              DAG.getDataLayout())));
3561       Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0), Tmp1);
3562     } else {
3563       // 0 -> Lo
3564       Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0),
3565                          Node->getOperand(0));
3566     }
3567     Results.push_back(Tmp1);
3568     break;
3569   }
3570   case ISD::STACKSAVE:
3571     // Expand to CopyFromReg if the target set
3572     // StackPointerRegisterToSaveRestore.
3573     if (Register SP = TLI.getStackPointerRegisterToSaveRestore()) {
3574       Results.push_back(DAG.getCopyFromReg(Node->getOperand(0), dl, SP,
3575                                            Node->getValueType(0)));
3576       Results.push_back(Results[0].getValue(1));
3577     } else {
3578       Results.push_back(DAG.getUNDEF(Node->getValueType(0)));
3579       Results.push_back(Node->getOperand(0));
3580     }
3581     break;
3582   case ISD::STACKRESTORE:
3583     // Expand to CopyToReg if the target set
3584     // StackPointerRegisterToSaveRestore.
3585     if (Register SP = TLI.getStackPointerRegisterToSaveRestore()) {
3586       Results.push_back(DAG.getCopyToReg(Node->getOperand(0), dl, SP,
3587                                          Node->getOperand(1)));
3588     } else {
3589       Results.push_back(Node->getOperand(0));
3590     }
3591     break;
3592   case ISD::GET_DYNAMIC_AREA_OFFSET:
3593     Results.push_back(DAG.getConstant(0, dl, Node->getValueType(0)));
3594     Results.push_back(Results[0].getValue(0));
3595     break;
3596   case ISD::FCOPYSIGN:
3597     Results.push_back(ExpandFCOPYSIGN(Node));
3598     break;
3599   case ISD::FNEG:
3600     Results.push_back(ExpandFNEG(Node));
3601     break;
3602   case ISD::FABS:
3603     Results.push_back(ExpandFABS(Node));
3604     break;
3605   case ISD::IS_FPCLASS: {
3606     auto Test = static_cast<FPClassTest>(Node->getConstantOperandVal(1));
3607     if (SDValue Expanded =
3608             TLI.expandIS_FPCLASS(Node->getValueType(0), Node->getOperand(0),
3609                                  Test, Node->getFlags(), SDLoc(Node), DAG))
3610       Results.push_back(Expanded);
3611     break;
3612   }
3613   case ISD::SMIN:
3614   case ISD::SMAX:
3615   case ISD::UMIN:
3616   case ISD::UMAX: {
3617     // Expand Y = MAX(A, B) -> Y = (A > B) ? A : B
3618     ISD::CondCode Pred;
3619     switch (Node->getOpcode()) {
3620     default: llvm_unreachable("How did we get here?");
3621     case ISD::SMAX: Pred = ISD::SETGT; break;
3622     case ISD::SMIN: Pred = ISD::SETLT; break;
3623     case ISD::UMAX: Pred = ISD::SETUGT; break;
3624     case ISD::UMIN: Pred = ISD::SETULT; break;
3625     }
3626     Tmp1 = Node->getOperand(0);
3627     Tmp2 = Node->getOperand(1);
3628     Tmp1 = DAG.getSelectCC(dl, Tmp1, Tmp2, Tmp1, Tmp2, Pred);
3629     Results.push_back(Tmp1);
3630     break;
3631   }
3632   case ISD::FMINNUM:
3633   case ISD::FMAXNUM: {
3634     if (SDValue Expanded = TLI.expandFMINNUM_FMAXNUM(Node, DAG))
3635       Results.push_back(Expanded);
3636     break;
3637   }
3638   case ISD::FMINIMUM:
3639   case ISD::FMAXIMUM: {
3640     if (SDValue Expanded = TLI.expandFMINIMUM_FMAXIMUM(Node, DAG))
3641       Results.push_back(Expanded);
3642     break;
3643   }
3644   case ISD::FSIN:
3645   case ISD::FCOS: {
3646     EVT VT = Node->getValueType(0);
3647     // Turn fsin / fcos into ISD::FSINCOS node if there are a pair of fsin /
3648     // fcos which share the same operand and both are used.
3649     if ((TLI.isOperationLegalOrCustom(ISD::FSINCOS, VT) ||
3650          isSinCosLibcallAvailable(Node, TLI))
3651         && useSinCos(Node)) {
3652       SDVTList VTs = DAG.getVTList(VT, VT);
3653       Tmp1 = DAG.getNode(ISD::FSINCOS, dl, VTs, Node->getOperand(0));
3654       if (Node->getOpcode() == ISD::FCOS)
3655         Tmp1 = Tmp1.getValue(1);
3656       Results.push_back(Tmp1);
3657     }
3658     break;
3659   }
3660   case ISD::FLDEXP:
3661   case ISD::STRICT_FLDEXP: {
3662     EVT VT = Node->getValueType(0);
3663     RTLIB::Libcall LC = RTLIB::getLDEXP(VT);
3664     // Use the LibCall instead, it is very likely faster
3665     // FIXME: Use separate LibCall action.
3666     if (TLI.getLibcallName(LC))
3667       break;
3668 
3669     if (SDValue Expanded = expandLdexp(Node)) {
3670       Results.push_back(Expanded);
3671       if (Node->getOpcode() == ISD::STRICT_FLDEXP)
3672         Results.push_back(Expanded.getValue(1));
3673     }
3674 
3675     break;
3676   }
3677   case ISD::FFREXP: {
3678     RTLIB::Libcall LC = RTLIB::getFREXP(Node->getValueType(0));
3679     // Use the LibCall instead, it is very likely faster
3680     // FIXME: Use separate LibCall action.
3681     if (TLI.getLibcallName(LC))
3682       break;
3683 
3684     if (SDValue Expanded = expandFrexp(Node)) {
3685       Results.push_back(Expanded);
3686       Results.push_back(Expanded.getValue(1));
3687     }
3688     break;
3689   }
3690   case ISD::FMAD:
3691     llvm_unreachable("Illegal fmad should never be formed");
3692 
3693   case ISD::FP16_TO_FP:
3694     if (Node->getValueType(0) != MVT::f32) {
3695       // We can extend to types bigger than f32 in two steps without changing
3696       // the result. Since "f16 -> f32" is much more commonly available, give
3697       // CodeGen the option of emitting that before resorting to a libcall.
3698       SDValue Res =
3699           DAG.getNode(ISD::FP16_TO_FP, dl, MVT::f32, Node->getOperand(0));
3700       Results.push_back(
3701           DAG.getNode(ISD::FP_EXTEND, dl, Node->getValueType(0), Res));
3702     }
3703     break;
3704   case ISD::STRICT_BF16_TO_FP:
3705   case ISD::STRICT_FP16_TO_FP:
3706     if (Node->getValueType(0) != MVT::f32) {
3707       // We can extend to types bigger than f32 in two steps without changing
3708       // the result. Since "f16 -> f32" is much more commonly available, give
3709       // CodeGen the option of emitting that before resorting to a libcall.
3710       SDValue Res = DAG.getNode(Node->getOpcode(), dl, {MVT::f32, MVT::Other},
3711                                 {Node->getOperand(0), Node->getOperand(1)});
3712       Res = DAG.getNode(ISD::STRICT_FP_EXTEND, dl,
3713                         {Node->getValueType(0), MVT::Other},
3714                         {Res.getValue(1), Res});
3715       Results.push_back(Res);
3716       Results.push_back(Res.getValue(1));
3717     }
3718     break;
3719   case ISD::FP_TO_FP16:
3720     LLVM_DEBUG(dbgs() << "Legalizing FP_TO_FP16\n");
3721     if (!TLI.useSoftFloat() && TM.Options.UnsafeFPMath) {
3722       SDValue Op = Node->getOperand(0);
3723       MVT SVT = Op.getSimpleValueType();
3724       if ((SVT == MVT::f64 || SVT == MVT::f80) &&
3725           TLI.isOperationLegalOrCustom(ISD::FP_TO_FP16, MVT::f32)) {
3726         // Under fastmath, we can expand this node into a fround followed by
3727         // a float-half conversion.
3728         SDValue FloatVal =
3729             DAG.getNode(ISD::FP_ROUND, dl, MVT::f32, Op,
3730                         DAG.getIntPtrConstant(0, dl, /*isTarget=*/true));
3731         Results.push_back(
3732             DAG.getNode(ISD::FP_TO_FP16, dl, Node->getValueType(0), FloatVal));
3733       }
3734     }
3735     break;
3736   case ISD::ConstantFP: {
3737     ConstantFPSDNode *CFP = cast<ConstantFPSDNode>(Node);
3738     // Check to see if this FP immediate is already legal.
3739     // If this is a legal constant, turn it into a TargetConstantFP node.
3740     if (!TLI.isFPImmLegal(CFP->getValueAPF(), Node->getValueType(0),
3741                           DAG.shouldOptForSize()))
3742       Results.push_back(ExpandConstantFP(CFP, true));
3743     break;
3744   }
3745   case ISD::Constant: {
3746     ConstantSDNode *CP = cast<ConstantSDNode>(Node);
3747     Results.push_back(ExpandConstant(CP));
3748     break;
3749   }
3750   case ISD::FSUB: {
3751     EVT VT = Node->getValueType(0);
3752     if (TLI.isOperationLegalOrCustom(ISD::FADD, VT) &&
3753         TLI.isOperationLegalOrCustom(ISD::FNEG, VT)) {
3754       const SDNodeFlags Flags = Node->getFlags();
3755       Tmp1 = DAG.getNode(ISD::FNEG, dl, VT, Node->getOperand(1));
3756       Tmp1 = DAG.getNode(ISD::FADD, dl, VT, Node->getOperand(0), Tmp1, Flags);
3757       Results.push_back(Tmp1);
3758     }
3759     break;
3760   }
3761   case ISD::SUB: {
3762     EVT VT = Node->getValueType(0);
3763     assert(TLI.isOperationLegalOrCustom(ISD::ADD, VT) &&
3764            TLI.isOperationLegalOrCustom(ISD::XOR, VT) &&
3765            "Don't know how to expand this subtraction!");
3766     Tmp1 = DAG.getNOT(dl, Node->getOperand(1), VT);
3767     Tmp1 = DAG.getNode(ISD::ADD, dl, VT, Tmp1, DAG.getConstant(1, dl, VT));
3768     Results.push_back(DAG.getNode(ISD::ADD, dl, VT, Node->getOperand(0), Tmp1));
3769     break;
3770   }
3771   case ISD::UREM:
3772   case ISD::SREM:
3773     if (TLI.expandREM(Node, Tmp1, DAG))
3774       Results.push_back(Tmp1);
3775     break;
3776   case ISD::UDIV:
3777   case ISD::SDIV: {
3778     bool isSigned = Node->getOpcode() == ISD::SDIV;
3779     unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
3780     EVT VT = Node->getValueType(0);
3781     if (TLI.isOperationLegalOrCustom(DivRemOpc, VT)) {
3782       SDVTList VTs = DAG.getVTList(VT, VT);
3783       Tmp1 = DAG.getNode(DivRemOpc, dl, VTs, Node->getOperand(0),
3784                          Node->getOperand(1));
3785       Results.push_back(Tmp1);
3786     }
3787     break;
3788   }
3789   case ISD::MULHU:
3790   case ISD::MULHS: {
3791     unsigned ExpandOpcode =
3792         Node->getOpcode() == ISD::MULHU ? ISD::UMUL_LOHI : ISD::SMUL_LOHI;
3793     EVT VT = Node->getValueType(0);
3794     SDVTList VTs = DAG.getVTList(VT, VT);
3795 
3796     Tmp1 = DAG.getNode(ExpandOpcode, dl, VTs, Node->getOperand(0),
3797                        Node->getOperand(1));
3798     Results.push_back(Tmp1.getValue(1));
3799     break;
3800   }
3801   case ISD::UMUL_LOHI:
3802   case ISD::SMUL_LOHI: {
3803     SDValue LHS = Node->getOperand(0);
3804     SDValue RHS = Node->getOperand(1);
3805     MVT VT = LHS.getSimpleValueType();
3806     unsigned MULHOpcode =
3807         Node->getOpcode() == ISD::UMUL_LOHI ? ISD::MULHU : ISD::MULHS;
3808 
3809     if (TLI.isOperationLegalOrCustom(MULHOpcode, VT)) {
3810       Results.push_back(DAG.getNode(ISD::MUL, dl, VT, LHS, RHS));
3811       Results.push_back(DAG.getNode(MULHOpcode, dl, VT, LHS, RHS));
3812       break;
3813     }
3814 
3815     SmallVector<SDValue, 4> Halves;
3816     EVT HalfType = EVT(VT).getHalfSizedIntegerVT(*DAG.getContext());
3817     assert(TLI.isTypeLegal(HalfType));
3818     if (TLI.expandMUL_LOHI(Node->getOpcode(), VT, dl, LHS, RHS, Halves,
3819                            HalfType, DAG,
3820                            TargetLowering::MulExpansionKind::Always)) {
3821       for (unsigned i = 0; i < 2; ++i) {
3822         SDValue Lo = DAG.getNode(ISD::ZERO_EXTEND, dl, VT, Halves[2 * i]);
3823         SDValue Hi = DAG.getNode(ISD::ANY_EXTEND, dl, VT, Halves[2 * i + 1]);
3824         SDValue Shift = DAG.getConstant(
3825             HalfType.getScalarSizeInBits(), dl,
3826             TLI.getShiftAmountTy(HalfType, DAG.getDataLayout()));
3827         Hi = DAG.getNode(ISD::SHL, dl, VT, Hi, Shift);
3828         Results.push_back(DAG.getNode(ISD::OR, dl, VT, Lo, Hi));
3829       }
3830       break;
3831     }
3832     break;
3833   }
3834   case ISD::MUL: {
3835     EVT VT = Node->getValueType(0);
3836     SDVTList VTs = DAG.getVTList(VT, VT);
3837     // See if multiply or divide can be lowered using two-result operations.
3838     // We just need the low half of the multiply; try both the signed
3839     // and unsigned forms. If the target supports both SMUL_LOHI and
3840     // UMUL_LOHI, form a preference by checking which forms of plain
3841     // MULH it supports.
3842     bool HasSMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::SMUL_LOHI, VT);
3843     bool HasUMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::UMUL_LOHI, VT);
3844     bool HasMULHS = TLI.isOperationLegalOrCustom(ISD::MULHS, VT);
3845     bool HasMULHU = TLI.isOperationLegalOrCustom(ISD::MULHU, VT);
3846     unsigned OpToUse = 0;
3847     if (HasSMUL_LOHI && !HasMULHS) {
3848       OpToUse = ISD::SMUL_LOHI;
3849     } else if (HasUMUL_LOHI && !HasMULHU) {
3850       OpToUse = ISD::UMUL_LOHI;
3851     } else if (HasSMUL_LOHI) {
3852       OpToUse = ISD::SMUL_LOHI;
3853     } else if (HasUMUL_LOHI) {
3854       OpToUse = ISD::UMUL_LOHI;
3855     }
3856     if (OpToUse) {
3857       Results.push_back(DAG.getNode(OpToUse, dl, VTs, Node->getOperand(0),
3858                                     Node->getOperand(1)));
3859       break;
3860     }
3861 
3862     SDValue Lo, Hi;
3863     EVT HalfType = VT.getHalfSizedIntegerVT(*DAG.getContext());
3864     if (TLI.isOperationLegalOrCustom(ISD::ZERO_EXTEND, VT) &&
3865         TLI.isOperationLegalOrCustom(ISD::ANY_EXTEND, VT) &&
3866         TLI.isOperationLegalOrCustom(ISD::SHL, VT) &&
3867         TLI.isOperationLegalOrCustom(ISD::OR, VT) &&
3868         TLI.expandMUL(Node, Lo, Hi, HalfType, DAG,
3869                       TargetLowering::MulExpansionKind::OnlyLegalOrCustom)) {
3870       Lo = DAG.getNode(ISD::ZERO_EXTEND, dl, VT, Lo);
3871       Hi = DAG.getNode(ISD::ANY_EXTEND, dl, VT, Hi);
3872       SDValue Shift =
3873           DAG.getConstant(HalfType.getSizeInBits(), dl,
3874                           TLI.getShiftAmountTy(HalfType, DAG.getDataLayout()));
3875       Hi = DAG.getNode(ISD::SHL, dl, VT, Hi, Shift);
3876       Results.push_back(DAG.getNode(ISD::OR, dl, VT, Lo, Hi));
3877     }
3878     break;
3879   }
3880   case ISD::FSHL:
3881   case ISD::FSHR:
3882     if (SDValue Expanded = TLI.expandFunnelShift(Node, DAG))
3883       Results.push_back(Expanded);
3884     break;
3885   case ISD::ROTL:
3886   case ISD::ROTR:
3887     if (SDValue Expanded = TLI.expandROT(Node, true /*AllowVectorOps*/, DAG))
3888       Results.push_back(Expanded);
3889     break;
3890   case ISD::SADDSAT:
3891   case ISD::UADDSAT:
3892   case ISD::SSUBSAT:
3893   case ISD::USUBSAT:
3894     Results.push_back(TLI.expandAddSubSat(Node, DAG));
3895     break;
3896   case ISD::SCMP:
3897   case ISD::UCMP:
3898     Results.push_back(TLI.expandCMP(Node, DAG));
3899     break;
3900   case ISD::SSHLSAT:
3901   case ISD::USHLSAT:
3902     Results.push_back(TLI.expandShlSat(Node, DAG));
3903     break;
3904   case ISD::SMULFIX:
3905   case ISD::SMULFIXSAT:
3906   case ISD::UMULFIX:
3907   case ISD::UMULFIXSAT:
3908     Results.push_back(TLI.expandFixedPointMul(Node, DAG));
3909     break;
3910   case ISD::SDIVFIX:
3911   case ISD::SDIVFIXSAT:
3912   case ISD::UDIVFIX:
3913   case ISD::UDIVFIXSAT:
3914     if (SDValue V = TLI.expandFixedPointDiv(Node->getOpcode(), SDLoc(Node),
3915                                             Node->getOperand(0),
3916                                             Node->getOperand(1),
3917                                             Node->getConstantOperandVal(2),
3918                                             DAG)) {
3919       Results.push_back(V);
3920       break;
3921     }
3922     // FIXME: We might want to retry here with a wider type if we fail, if that
3923     // type is legal.
3924     // FIXME: Technically, so long as we only have sdivfixes where BW+Scale is
3925     // <= 128 (which is the case for all of the default Embedded-C types),
3926     // we will only get here with types and scales that we could always expand
3927     // if we were allowed to generate libcalls to division functions of illegal
3928     // type. But we cannot do that.
3929     llvm_unreachable("Cannot expand DIVFIX!");
3930   case ISD::UADDO_CARRY:
3931   case ISD::USUBO_CARRY: {
3932     SDValue LHS = Node->getOperand(0);
3933     SDValue RHS = Node->getOperand(1);
3934     SDValue Carry = Node->getOperand(2);
3935 
3936     bool IsAdd = Node->getOpcode() == ISD::UADDO_CARRY;
3937 
3938     // Initial add of the 2 operands.
3939     unsigned Op = IsAdd ? ISD::ADD : ISD::SUB;
3940     EVT VT = LHS.getValueType();
3941     SDValue Sum = DAG.getNode(Op, dl, VT, LHS, RHS);
3942 
3943     // Initial check for overflow.
3944     EVT CarryType = Node->getValueType(1);
3945     EVT SetCCType = getSetCCResultType(Node->getValueType(0));
3946     ISD::CondCode CC = IsAdd ? ISD::SETULT : ISD::SETUGT;
3947     SDValue Overflow = DAG.getSetCC(dl, SetCCType, Sum, LHS, CC);
3948 
3949     // Add of the sum and the carry.
3950     SDValue One = DAG.getConstant(1, dl, VT);
3951     SDValue CarryExt =
3952         DAG.getNode(ISD::AND, dl, VT, DAG.getZExtOrTrunc(Carry, dl, VT), One);
3953     SDValue Sum2 = DAG.getNode(Op, dl, VT, Sum, CarryExt);
3954 
3955     // Second check for overflow. If we are adding, we can only overflow if the
3956     // initial sum is all 1s ang the carry is set, resulting in a new sum of 0.
3957     // If we are subtracting, we can only overflow if the initial sum is 0 and
3958     // the carry is set, resulting in a new sum of all 1s.
3959     SDValue Zero = DAG.getConstant(0, dl, VT);
3960     SDValue Overflow2 =
3961         IsAdd ? DAG.getSetCC(dl, SetCCType, Sum2, Zero, ISD::SETEQ)
3962               : DAG.getSetCC(dl, SetCCType, Sum, Zero, ISD::SETEQ);
3963     Overflow2 = DAG.getNode(ISD::AND, dl, SetCCType, Overflow2,
3964                             DAG.getZExtOrTrunc(Carry, dl, SetCCType));
3965 
3966     SDValue ResultCarry =
3967         DAG.getNode(ISD::OR, dl, SetCCType, Overflow, Overflow2);
3968 
3969     Results.push_back(Sum2);
3970     Results.push_back(DAG.getBoolExtOrTrunc(ResultCarry, dl, CarryType, VT));
3971     break;
3972   }
3973   case ISD::SADDO:
3974   case ISD::SSUBO: {
3975     SDValue Result, Overflow;
3976     TLI.expandSADDSUBO(Node, Result, Overflow, DAG);
3977     Results.push_back(Result);
3978     Results.push_back(Overflow);
3979     break;
3980   }
3981   case ISD::UADDO:
3982   case ISD::USUBO: {
3983     SDValue Result, Overflow;
3984     TLI.expandUADDSUBO(Node, Result, Overflow, DAG);
3985     Results.push_back(Result);
3986     Results.push_back(Overflow);
3987     break;
3988   }
3989   case ISD::UMULO:
3990   case ISD::SMULO: {
3991     SDValue Result, Overflow;
3992     if (TLI.expandMULO(Node, Result, Overflow, DAG)) {
3993       Results.push_back(Result);
3994       Results.push_back(Overflow);
3995     }
3996     break;
3997   }
3998   case ISD::BUILD_PAIR: {
3999     EVT PairTy = Node->getValueType(0);
4000     Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, PairTy, Node->getOperand(0));
4001     Tmp2 = DAG.getNode(ISD::ANY_EXTEND, dl, PairTy, Node->getOperand(1));
4002     Tmp2 = DAG.getNode(
4003         ISD::SHL, dl, PairTy, Tmp2,
4004         DAG.getConstant(PairTy.getSizeInBits() / 2, dl,
4005                         TLI.getShiftAmountTy(PairTy, DAG.getDataLayout())));
4006     Results.push_back(DAG.getNode(ISD::OR, dl, PairTy, Tmp1, Tmp2));
4007     break;
4008   }
4009   case ISD::SELECT:
4010     Tmp1 = Node->getOperand(0);
4011     Tmp2 = Node->getOperand(1);
4012     Tmp3 = Node->getOperand(2);
4013     if (Tmp1.getOpcode() == ISD::SETCC) {
4014       Tmp1 = DAG.getSelectCC(dl, Tmp1.getOperand(0), Tmp1.getOperand(1),
4015                              Tmp2, Tmp3,
4016                              cast<CondCodeSDNode>(Tmp1.getOperand(2))->get());
4017     } else {
4018       Tmp1 = DAG.getSelectCC(dl, Tmp1,
4019                              DAG.getConstant(0, dl, Tmp1.getValueType()),
4020                              Tmp2, Tmp3, ISD::SETNE);
4021     }
4022     Tmp1->setFlags(Node->getFlags());
4023     Results.push_back(Tmp1);
4024     break;
4025   case ISD::BR_JT: {
4026     SDValue Chain = Node->getOperand(0);
4027     SDValue Table = Node->getOperand(1);
4028     SDValue Index = Node->getOperand(2);
4029     int JTI = cast<JumpTableSDNode>(Table.getNode())->getIndex();
4030 
4031     const DataLayout &TD = DAG.getDataLayout();
4032     EVT PTy = TLI.getPointerTy(TD);
4033 
4034     unsigned EntrySize =
4035       DAG.getMachineFunction().getJumpTableInfo()->getEntrySize(TD);
4036 
4037     // For power-of-two jumptable entry sizes convert multiplication to a shift.
4038     // This transformation needs to be done here since otherwise the MIPS
4039     // backend will end up emitting a three instruction multiply sequence
4040     // instead of a single shift and MSP430 will call a runtime function.
4041     if (llvm::isPowerOf2_32(EntrySize))
4042       Index = DAG.getNode(
4043           ISD::SHL, dl, Index.getValueType(), Index,
4044           DAG.getConstant(llvm::Log2_32(EntrySize), dl, Index.getValueType()));
4045     else
4046       Index = DAG.getNode(ISD::MUL, dl, Index.getValueType(), Index,
4047                           DAG.getConstant(EntrySize, dl, Index.getValueType()));
4048     SDValue Addr = DAG.getNode(ISD::ADD, dl, Index.getValueType(),
4049                                Index, Table);
4050 
4051     EVT MemVT = EVT::getIntegerVT(*DAG.getContext(), EntrySize * 8);
4052     SDValue LD = DAG.getExtLoad(
4053         ISD::SEXTLOAD, dl, PTy, Chain, Addr,
4054         MachinePointerInfo::getJumpTable(DAG.getMachineFunction()), MemVT);
4055     Addr = LD;
4056     if (TLI.isJumpTableRelative()) {
4057       // For PIC, the sequence is:
4058       // BRIND(load(Jumptable + index) + RelocBase)
4059       // RelocBase can be JumpTable, GOT or some sort of global base.
4060       Addr = DAG.getNode(ISD::ADD, dl, PTy, Addr,
4061                           TLI.getPICJumpTableRelocBase(Table, DAG));
4062     }
4063 
4064     Tmp1 = TLI.expandIndirectJTBranch(dl, LD.getValue(1), Addr, JTI, DAG);
4065     Results.push_back(Tmp1);
4066     break;
4067   }
4068   case ISD::BRCOND:
4069     // Expand brcond's setcc into its constituent parts and create a BR_CC
4070     // Node.
4071     Tmp1 = Node->getOperand(0);
4072     Tmp2 = Node->getOperand(1);
4073     if (Tmp2.getOpcode() == ISD::SETCC &&
4074         TLI.isOperationLegalOrCustom(ISD::BR_CC,
4075                                      Tmp2.getOperand(0).getValueType())) {
4076       Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other, Tmp1, Tmp2.getOperand(2),
4077                          Tmp2.getOperand(0), Tmp2.getOperand(1),
4078                          Node->getOperand(2));
4079     } else {
4080       // We test only the i1 bit.  Skip the AND if UNDEF or another AND.
4081       if (Tmp2.isUndef() ||
4082           (Tmp2.getOpcode() == ISD::AND && isOneConstant(Tmp2.getOperand(1))))
4083         Tmp3 = Tmp2;
4084       else
4085         Tmp3 = DAG.getNode(ISD::AND, dl, Tmp2.getValueType(), Tmp2,
4086                            DAG.getConstant(1, dl, Tmp2.getValueType()));
4087       Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other, Tmp1,
4088                          DAG.getCondCode(ISD::SETNE), Tmp3,
4089                          DAG.getConstant(0, dl, Tmp3.getValueType()),
4090                          Node->getOperand(2));
4091     }
4092     Results.push_back(Tmp1);
4093     break;
4094   case ISD::SETCC:
4095   case ISD::VP_SETCC:
4096   case ISD::STRICT_FSETCC:
4097   case ISD::STRICT_FSETCCS: {
4098     bool IsVP = Node->getOpcode() == ISD::VP_SETCC;
4099     bool IsStrict = Node->getOpcode() == ISD::STRICT_FSETCC ||
4100                     Node->getOpcode() == ISD::STRICT_FSETCCS;
4101     bool IsSignaling = Node->getOpcode() == ISD::STRICT_FSETCCS;
4102     SDValue Chain = IsStrict ? Node->getOperand(0) : SDValue();
4103     unsigned Offset = IsStrict ? 1 : 0;
4104     Tmp1 = Node->getOperand(0 + Offset);
4105     Tmp2 = Node->getOperand(1 + Offset);
4106     Tmp3 = Node->getOperand(2 + Offset);
4107     SDValue Mask, EVL;
4108     if (IsVP) {
4109       Mask = Node->getOperand(3 + Offset);
4110       EVL = Node->getOperand(4 + Offset);
4111     }
4112     bool Legalized = TLI.LegalizeSetCCCondCode(
4113         DAG, Node->getValueType(0), Tmp1, Tmp2, Tmp3, Mask, EVL, NeedInvert, dl,
4114         Chain, IsSignaling);
4115 
4116     if (Legalized) {
4117       // If we expanded the SETCC by swapping LHS and RHS, or by inverting the
4118       // condition code, create a new SETCC node.
4119       if (Tmp3.getNode()) {
4120         if (IsStrict) {
4121           Tmp1 = DAG.getNode(Node->getOpcode(), dl, Node->getVTList(),
4122                              {Chain, Tmp1, Tmp2, Tmp3}, Node->getFlags());
4123           Chain = Tmp1.getValue(1);
4124         } else if (IsVP) {
4125           Tmp1 = DAG.getNode(Node->getOpcode(), dl, Node->getValueType(0),
4126                              {Tmp1, Tmp2, Tmp3, Mask, EVL}, Node->getFlags());
4127         } else {
4128           Tmp1 = DAG.getNode(Node->getOpcode(), dl, Node->getValueType(0), Tmp1,
4129                              Tmp2, Tmp3, Node->getFlags());
4130         }
4131       }
4132 
4133       // If we expanded the SETCC by inverting the condition code, then wrap
4134       // the existing SETCC in a NOT to restore the intended condition.
4135       if (NeedInvert) {
4136         if (!IsVP)
4137           Tmp1 = DAG.getLogicalNOT(dl, Tmp1, Tmp1->getValueType(0));
4138         else
4139           Tmp1 =
4140               DAG.getVPLogicalNOT(dl, Tmp1, Mask, EVL, Tmp1->getValueType(0));
4141       }
4142 
4143       Results.push_back(Tmp1);
4144       if (IsStrict)
4145         Results.push_back(Chain);
4146 
4147       break;
4148     }
4149 
4150     // FIXME: It seems Legalized is false iff CCCode is Legal. I don't
4151     // understand if this code is useful for strict nodes.
4152     assert(!IsStrict && "Don't know how to expand for strict nodes.");
4153 
4154     // Otherwise, SETCC for the given comparison type must be completely
4155     // illegal; expand it into a SELECT_CC.
4156     // FIXME: This drops the mask/evl for VP_SETCC.
4157     EVT VT = Node->getValueType(0);
4158     EVT Tmp1VT = Tmp1.getValueType();
4159     Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, VT, Tmp1, Tmp2,
4160                        DAG.getBoolConstant(true, dl, VT, Tmp1VT),
4161                        DAG.getBoolConstant(false, dl, VT, Tmp1VT), Tmp3);
4162     Tmp1->setFlags(Node->getFlags());
4163     Results.push_back(Tmp1);
4164     break;
4165   }
4166   case ISD::SELECT_CC: {
4167     // TODO: need to add STRICT_SELECT_CC and STRICT_SELECT_CCS
4168     Tmp1 = Node->getOperand(0);   // LHS
4169     Tmp2 = Node->getOperand(1);   // RHS
4170     Tmp3 = Node->getOperand(2);   // True
4171     Tmp4 = Node->getOperand(3);   // False
4172     EVT VT = Node->getValueType(0);
4173     SDValue Chain;
4174     SDValue CC = Node->getOperand(4);
4175     ISD::CondCode CCOp = cast<CondCodeSDNode>(CC)->get();
4176 
4177     if (TLI.isCondCodeLegalOrCustom(CCOp, Tmp1.getSimpleValueType())) {
4178       // If the condition code is legal, then we need to expand this
4179       // node using SETCC and SELECT.
4180       EVT CmpVT = Tmp1.getValueType();
4181       assert(!TLI.isOperationExpand(ISD::SELECT, VT) &&
4182              "Cannot expand ISD::SELECT_CC when ISD::SELECT also needs to be "
4183              "expanded.");
4184       EVT CCVT = getSetCCResultType(CmpVT);
4185       SDValue Cond = DAG.getNode(ISD::SETCC, dl, CCVT, Tmp1, Tmp2, CC, Node->getFlags());
4186       Results.push_back(
4187           DAG.getSelect(dl, VT, Cond, Tmp3, Tmp4, Node->getFlags()));
4188       break;
4189     }
4190 
4191     // SELECT_CC is legal, so the condition code must not be.
4192     bool Legalized = false;
4193     // Try to legalize by inverting the condition.  This is for targets that
4194     // might support an ordered version of a condition, but not the unordered
4195     // version (or vice versa).
4196     ISD::CondCode InvCC = ISD::getSetCCInverse(CCOp, Tmp1.getValueType());
4197     if (TLI.isCondCodeLegalOrCustom(InvCC, Tmp1.getSimpleValueType())) {
4198       // Use the new condition code and swap true and false
4199       Legalized = true;
4200       Tmp1 = DAG.getSelectCC(dl, Tmp1, Tmp2, Tmp4, Tmp3, InvCC);
4201       Tmp1->setFlags(Node->getFlags());
4202     } else {
4203       // If The inverse is not legal, then try to swap the arguments using
4204       // the inverse condition code.
4205       ISD::CondCode SwapInvCC = ISD::getSetCCSwappedOperands(InvCC);
4206       if (TLI.isCondCodeLegalOrCustom(SwapInvCC, Tmp1.getSimpleValueType())) {
4207         // The swapped inverse condition is legal, so swap true and false,
4208         // lhs and rhs.
4209         Legalized = true;
4210         Tmp1 = DAG.getSelectCC(dl, Tmp2, Tmp1, Tmp4, Tmp3, SwapInvCC);
4211         Tmp1->setFlags(Node->getFlags());
4212       }
4213     }
4214 
4215     if (!Legalized) {
4216       Legalized = TLI.LegalizeSetCCCondCode(
4217           DAG, getSetCCResultType(Tmp1.getValueType()), Tmp1, Tmp2, CC,
4218           /*Mask*/ SDValue(), /*EVL*/ SDValue(), NeedInvert, dl, Chain);
4219 
4220       assert(Legalized && "Can't legalize SELECT_CC with legal condition!");
4221 
4222       // If we expanded the SETCC by inverting the condition code, then swap
4223       // the True/False operands to match.
4224       if (NeedInvert)
4225         std::swap(Tmp3, Tmp4);
4226 
4227       // If we expanded the SETCC by swapping LHS and RHS, or by inverting the
4228       // condition code, create a new SELECT_CC node.
4229       if (CC.getNode()) {
4230         Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, Node->getValueType(0),
4231                            Tmp1, Tmp2, Tmp3, Tmp4, CC);
4232       } else {
4233         Tmp2 = DAG.getConstant(0, dl, Tmp1.getValueType());
4234         CC = DAG.getCondCode(ISD::SETNE);
4235         Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, Node->getValueType(0), Tmp1,
4236                            Tmp2, Tmp3, Tmp4, CC);
4237       }
4238       Tmp1->setFlags(Node->getFlags());
4239     }
4240     Results.push_back(Tmp1);
4241     break;
4242   }
4243   case ISD::BR_CC: {
4244     // TODO: need to add STRICT_BR_CC and STRICT_BR_CCS
4245     SDValue Chain;
4246     Tmp1 = Node->getOperand(0);              // Chain
4247     Tmp2 = Node->getOperand(2);              // LHS
4248     Tmp3 = Node->getOperand(3);              // RHS
4249     Tmp4 = Node->getOperand(1);              // CC
4250 
4251     bool Legalized = TLI.LegalizeSetCCCondCode(
4252         DAG, getSetCCResultType(Tmp2.getValueType()), Tmp2, Tmp3, Tmp4,
4253         /*Mask*/ SDValue(), /*EVL*/ SDValue(), NeedInvert, dl, Chain);
4254     (void)Legalized;
4255     assert(Legalized && "Can't legalize BR_CC with legal condition!");
4256 
4257     // If we expanded the SETCC by swapping LHS and RHS, create a new BR_CC
4258     // node.
4259     if (Tmp4.getNode()) {
4260       assert(!NeedInvert && "Don't know how to invert BR_CC!");
4261 
4262       Tmp1 = DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0), Tmp1,
4263                          Tmp4, Tmp2, Tmp3, Node->getOperand(4));
4264     } else {
4265       Tmp3 = DAG.getConstant(0, dl, Tmp2.getValueType());
4266       Tmp4 = DAG.getCondCode(NeedInvert ? ISD::SETEQ : ISD::SETNE);
4267       Tmp1 = DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0), Tmp1, Tmp4,
4268                          Tmp2, Tmp3, Node->getOperand(4));
4269     }
4270     Results.push_back(Tmp1);
4271     break;
4272   }
4273   case ISD::BUILD_VECTOR:
4274     Results.push_back(ExpandBUILD_VECTOR(Node));
4275     break;
4276   case ISD::SPLAT_VECTOR:
4277     Results.push_back(ExpandSPLAT_VECTOR(Node));
4278     break;
4279   case ISD::SRA:
4280   case ISD::SRL:
4281   case ISD::SHL: {
4282     // Scalarize vector SRA/SRL/SHL.
4283     EVT VT = Node->getValueType(0);
4284     assert(VT.isVector() && "Unable to legalize non-vector shift");
4285     assert(TLI.isTypeLegal(VT.getScalarType())&& "Element type must be legal");
4286     unsigned NumElem = VT.getVectorNumElements();
4287 
4288     SmallVector<SDValue, 8> Scalars;
4289     for (unsigned Idx = 0; Idx < NumElem; Idx++) {
4290       SDValue Ex =
4291           DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, VT.getScalarType(),
4292                       Node->getOperand(0), DAG.getVectorIdxConstant(Idx, dl));
4293       SDValue Sh =
4294           DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, VT.getScalarType(),
4295                       Node->getOperand(1), DAG.getVectorIdxConstant(Idx, dl));
4296       Scalars.push_back(DAG.getNode(Node->getOpcode(), dl,
4297                                     VT.getScalarType(), Ex, Sh));
4298     }
4299 
4300     SDValue Result = DAG.getBuildVector(Node->getValueType(0), dl, Scalars);
4301     Results.push_back(Result);
4302     break;
4303   }
4304   case ISD::VECREDUCE_FADD:
4305   case ISD::VECREDUCE_FMUL:
4306   case ISD::VECREDUCE_ADD:
4307   case ISD::VECREDUCE_MUL:
4308   case ISD::VECREDUCE_AND:
4309   case ISD::VECREDUCE_OR:
4310   case ISD::VECREDUCE_XOR:
4311   case ISD::VECREDUCE_SMAX:
4312   case ISD::VECREDUCE_SMIN:
4313   case ISD::VECREDUCE_UMAX:
4314   case ISD::VECREDUCE_UMIN:
4315   case ISD::VECREDUCE_FMAX:
4316   case ISD::VECREDUCE_FMIN:
4317   case ISD::VECREDUCE_FMAXIMUM:
4318   case ISD::VECREDUCE_FMINIMUM:
4319     Results.push_back(TLI.expandVecReduce(Node, DAG));
4320     break;
4321   case ISD::VP_CTTZ_ELTS:
4322   case ISD::VP_CTTZ_ELTS_ZERO_UNDEF:
4323     Results.push_back(TLI.expandVPCTTZElements(Node, DAG));
4324     break;
4325   case ISD::CLEAR_CACHE:
4326     // The default expansion of llvm.clear_cache is simply a no-op for those
4327     // targets where it is not needed.
4328     Results.push_back(Node->getOperand(0));
4329     break;
4330   case ISD::GLOBAL_OFFSET_TABLE:
4331   case ISD::GlobalAddress:
4332   case ISD::GlobalTLSAddress:
4333   case ISD::ExternalSymbol:
4334   case ISD::ConstantPool:
4335   case ISD::JumpTable:
4336   case ISD::INTRINSIC_W_CHAIN:
4337   case ISD::INTRINSIC_WO_CHAIN:
4338   case ISD::INTRINSIC_VOID:
4339     // FIXME: Custom lowering for these operations shouldn't return null!
4340     // Return true so that we don't call ConvertNodeToLibcall which also won't
4341     // do anything.
4342     return true;
4343   }
4344 
4345   if (!TLI.isStrictFPEnabled() && Results.empty() && Node->isStrictFPOpcode()) {
4346     // FIXME: We were asked to expand a strict floating-point operation,
4347     // but there is currently no expansion implemented that would preserve
4348     // the "strict" properties.  For now, we just fall back to the non-strict
4349     // version if that is legal on the target.  The actual mutation of the
4350     // operation will happen in SelectionDAGISel::DoInstructionSelection.
4351     switch (Node->getOpcode()) {
4352     default:
4353       if (TLI.getStrictFPOperationAction(Node->getOpcode(),
4354                                          Node->getValueType(0))
4355           == TargetLowering::Legal)
4356         return true;
4357       break;
4358     case ISD::STRICT_FSUB: {
4359       if (TLI.getStrictFPOperationAction(
4360               ISD::STRICT_FSUB, Node->getValueType(0)) == TargetLowering::Legal)
4361         return true;
4362       if (TLI.getStrictFPOperationAction(
4363               ISD::STRICT_FADD, Node->getValueType(0)) != TargetLowering::Legal)
4364         break;
4365 
4366       EVT VT = Node->getValueType(0);
4367       const SDNodeFlags Flags = Node->getFlags();
4368       SDValue Neg = DAG.getNode(ISD::FNEG, dl, VT, Node->getOperand(2), Flags);
4369       SDValue Fadd = DAG.getNode(ISD::STRICT_FADD, dl, Node->getVTList(),
4370                                  {Node->getOperand(0), Node->getOperand(1), Neg},
4371                          Flags);
4372 
4373       Results.push_back(Fadd);
4374       Results.push_back(Fadd.getValue(1));
4375       break;
4376     }
4377     case ISD::STRICT_SINT_TO_FP:
4378     case ISD::STRICT_UINT_TO_FP:
4379     case ISD::STRICT_LRINT:
4380     case ISD::STRICT_LLRINT:
4381     case ISD::STRICT_LROUND:
4382     case ISD::STRICT_LLROUND:
4383       // These are registered by the operand type instead of the value
4384       // type. Reflect that here.
4385       if (TLI.getStrictFPOperationAction(Node->getOpcode(),
4386                                          Node->getOperand(1).getValueType())
4387           == TargetLowering::Legal)
4388         return true;
4389       break;
4390     }
4391   }
4392 
4393   // Replace the original node with the legalized result.
4394   if (Results.empty()) {
4395     LLVM_DEBUG(dbgs() << "Cannot expand node\n");
4396     return false;
4397   }
4398 
4399   LLVM_DEBUG(dbgs() << "Successfully expanded node\n");
4400   ReplaceNode(Node, Results.data());
4401   return true;
4402 }
4403 
4404 void SelectionDAGLegalize::ConvertNodeToLibcall(SDNode *Node) {
4405   LLVM_DEBUG(dbgs() << "Trying to convert node to libcall\n");
4406   SmallVector<SDValue, 8> Results;
4407   SDLoc dl(Node);
4408   // FIXME: Check flags on the node to see if we can use a finite call.
4409   unsigned Opc = Node->getOpcode();
4410   switch (Opc) {
4411   case ISD::ATOMIC_FENCE: {
4412     // If the target didn't lower this, lower it to '__sync_synchronize()' call
4413     // FIXME: handle "fence singlethread" more efficiently.
4414     TargetLowering::ArgListTy Args;
4415 
4416     TargetLowering::CallLoweringInfo CLI(DAG);
4417     CLI.setDebugLoc(dl)
4418         .setChain(Node->getOperand(0))
4419         .setLibCallee(
4420             CallingConv::C, Type::getVoidTy(*DAG.getContext()),
4421             DAG.getExternalSymbol("__sync_synchronize",
4422                                   TLI.getPointerTy(DAG.getDataLayout())),
4423             std::move(Args));
4424 
4425     std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
4426 
4427     Results.push_back(CallResult.second);
4428     break;
4429   }
4430   // By default, atomic intrinsics are marked Legal and lowered. Targets
4431   // which don't support them directly, however, may want libcalls, in which
4432   // case they mark them Expand, and we get here.
4433   case ISD::ATOMIC_SWAP:
4434   case ISD::ATOMIC_LOAD_ADD:
4435   case ISD::ATOMIC_LOAD_SUB:
4436   case ISD::ATOMIC_LOAD_AND:
4437   case ISD::ATOMIC_LOAD_CLR:
4438   case ISD::ATOMIC_LOAD_OR:
4439   case ISD::ATOMIC_LOAD_XOR:
4440   case ISD::ATOMIC_LOAD_NAND:
4441   case ISD::ATOMIC_LOAD_MIN:
4442   case ISD::ATOMIC_LOAD_MAX:
4443   case ISD::ATOMIC_LOAD_UMIN:
4444   case ISD::ATOMIC_LOAD_UMAX:
4445   case ISD::ATOMIC_CMP_SWAP: {
4446     MVT VT = cast<AtomicSDNode>(Node)->getMemoryVT().getSimpleVT();
4447     AtomicOrdering Order = cast<AtomicSDNode>(Node)->getMergedOrdering();
4448     RTLIB::Libcall LC = RTLIB::getOUTLINE_ATOMIC(Opc, Order, VT);
4449     EVT RetVT = Node->getValueType(0);
4450     TargetLowering::MakeLibCallOptions CallOptions;
4451     SmallVector<SDValue, 4> Ops;
4452     if (TLI.getLibcallName(LC)) {
4453       // If outline atomic available, prepare its arguments and expand.
4454       Ops.append(Node->op_begin() + 2, Node->op_end());
4455       Ops.push_back(Node->getOperand(1));
4456 
4457     } else {
4458       LC = RTLIB::getSYNC(Opc, VT);
4459       assert(LC != RTLIB::UNKNOWN_LIBCALL &&
4460              "Unexpected atomic op or value type!");
4461       // Arguments for expansion to sync libcall
4462       Ops.append(Node->op_begin() + 1, Node->op_end());
4463     }
4464     std::pair<SDValue, SDValue> Tmp = TLI.makeLibCall(DAG, LC, RetVT,
4465                                                       Ops, CallOptions,
4466                                                       SDLoc(Node),
4467                                                       Node->getOperand(0));
4468     Results.push_back(Tmp.first);
4469     Results.push_back(Tmp.second);
4470     break;
4471   }
4472   case ISD::TRAP: {
4473     // If this operation is not supported, lower it to 'abort()' call
4474     TargetLowering::ArgListTy Args;
4475     TargetLowering::CallLoweringInfo CLI(DAG);
4476     CLI.setDebugLoc(dl)
4477         .setChain(Node->getOperand(0))
4478         .setLibCallee(CallingConv::C, Type::getVoidTy(*DAG.getContext()),
4479                       DAG.getExternalSymbol(
4480                           "abort", TLI.getPointerTy(DAG.getDataLayout())),
4481                       std::move(Args));
4482     std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
4483 
4484     Results.push_back(CallResult.second);
4485     break;
4486   }
4487   case ISD::CLEAR_CACHE: {
4488     TargetLowering::MakeLibCallOptions CallOptions;
4489     SDValue InputChain = Node->getOperand(0);
4490     SDValue StartVal = Node->getOperand(1);
4491     SDValue EndVal = Node->getOperand(2);
4492     std::pair<SDValue, SDValue> Tmp = TLI.makeLibCall(
4493         DAG, RTLIB::CLEAR_CACHE, MVT::isVoid, {StartVal, EndVal}, CallOptions,
4494         SDLoc(Node), InputChain);
4495     Results.push_back(Tmp.second);
4496     break;
4497   }
4498   case ISD::FMINNUM:
4499   case ISD::STRICT_FMINNUM:
4500     ExpandFPLibCall(Node, RTLIB::FMIN_F32, RTLIB::FMIN_F64,
4501                     RTLIB::FMIN_F80, RTLIB::FMIN_F128,
4502                     RTLIB::FMIN_PPCF128, Results);
4503     break;
4504   // FIXME: We do not have libcalls for FMAXIMUM and FMINIMUM. So, we cannot use
4505   // libcall legalization for these nodes, but there is no default expasion for
4506   // these nodes either (see PR63267 for example).
4507   case ISD::FMAXNUM:
4508   case ISD::STRICT_FMAXNUM:
4509     ExpandFPLibCall(Node, RTLIB::FMAX_F32, RTLIB::FMAX_F64,
4510                     RTLIB::FMAX_F80, RTLIB::FMAX_F128,
4511                     RTLIB::FMAX_PPCF128, Results);
4512     break;
4513   case ISD::FSQRT:
4514   case ISD::STRICT_FSQRT:
4515     ExpandFPLibCall(Node, RTLIB::SQRT_F32, RTLIB::SQRT_F64,
4516                     RTLIB::SQRT_F80, RTLIB::SQRT_F128,
4517                     RTLIB::SQRT_PPCF128, Results);
4518     break;
4519   case ISD::FCBRT:
4520     ExpandFPLibCall(Node, RTLIB::CBRT_F32, RTLIB::CBRT_F64,
4521                     RTLIB::CBRT_F80, RTLIB::CBRT_F128,
4522                     RTLIB::CBRT_PPCF128, Results);
4523     break;
4524   case ISD::FSIN:
4525   case ISD::STRICT_FSIN:
4526     ExpandFPLibCall(Node, RTLIB::SIN_F32, RTLIB::SIN_F64,
4527                     RTLIB::SIN_F80, RTLIB::SIN_F128,
4528                     RTLIB::SIN_PPCF128, Results);
4529     break;
4530   case ISD::FCOS:
4531   case ISD::STRICT_FCOS:
4532     ExpandFPLibCall(Node, RTLIB::COS_F32, RTLIB::COS_F64,
4533                     RTLIB::COS_F80, RTLIB::COS_F128,
4534                     RTLIB::COS_PPCF128, Results);
4535     break;
4536   case ISD::FTAN:
4537   case ISD::STRICT_FTAN:
4538     ExpandFPLibCall(Node, RTLIB::TAN_F32, RTLIB::TAN_F64, RTLIB::TAN_F80,
4539                     RTLIB::TAN_F128, RTLIB::TAN_PPCF128, Results);
4540     break;
4541   case ISD::FASIN:
4542   case ISD::STRICT_FASIN:
4543     ExpandFPLibCall(Node, RTLIB::ASIN_F32, RTLIB::ASIN_F64, RTLIB::ASIN_F80,
4544                     RTLIB::ASIN_F128, RTLIB::ASIN_PPCF128, Results);
4545     break;
4546   case ISD::FACOS:
4547   case ISD::STRICT_FACOS:
4548     ExpandFPLibCall(Node, RTLIB::ACOS_F32, RTLIB::ACOS_F64, RTLIB::ACOS_F80,
4549                     RTLIB::ACOS_F128, RTLIB::ACOS_PPCF128, Results);
4550     break;
4551   case ISD::FATAN:
4552   case ISD::STRICT_FATAN:
4553     ExpandFPLibCall(Node, RTLIB::ATAN_F32, RTLIB::ATAN_F64, RTLIB::ATAN_F80,
4554                     RTLIB::ATAN_F128, RTLIB::ATAN_PPCF128, Results);
4555     break;
4556   case ISD::FSINH:
4557   case ISD::STRICT_FSINH:
4558     ExpandFPLibCall(Node, RTLIB::SINH_F32, RTLIB::SINH_F64, RTLIB::SINH_F80,
4559                     RTLIB::SINH_F128, RTLIB::SINH_PPCF128, Results);
4560     break;
4561   case ISD::FCOSH:
4562   case ISD::STRICT_FCOSH:
4563     ExpandFPLibCall(Node, RTLIB::COSH_F32, RTLIB::COSH_F64, RTLIB::COSH_F80,
4564                     RTLIB::COSH_F128, RTLIB::COSH_PPCF128, Results);
4565     break;
4566   case ISD::FTANH:
4567   case ISD::STRICT_FTANH:
4568     ExpandFPLibCall(Node, RTLIB::TANH_F32, RTLIB::TANH_F64, RTLIB::TANH_F80,
4569                     RTLIB::TANH_F128, RTLIB::TANH_PPCF128, Results);
4570     break;
4571   case ISD::FSINCOS:
4572     // Expand into sincos libcall.
4573     ExpandSinCosLibCall(Node, Results);
4574     break;
4575   case ISD::FLOG:
4576   case ISD::STRICT_FLOG:
4577     ExpandFPLibCall(Node, RTLIB::LOG_F32, RTLIB::LOG_F64, RTLIB::LOG_F80,
4578                     RTLIB::LOG_F128, RTLIB::LOG_PPCF128, Results);
4579     break;
4580   case ISD::FLOG2:
4581   case ISD::STRICT_FLOG2:
4582     ExpandFPLibCall(Node, RTLIB::LOG2_F32, RTLIB::LOG2_F64, RTLIB::LOG2_F80,
4583                     RTLIB::LOG2_F128, RTLIB::LOG2_PPCF128, Results);
4584     break;
4585   case ISD::FLOG10:
4586   case ISD::STRICT_FLOG10:
4587     ExpandFPLibCall(Node, RTLIB::LOG10_F32, RTLIB::LOG10_F64, RTLIB::LOG10_F80,
4588                     RTLIB::LOG10_F128, RTLIB::LOG10_PPCF128, Results);
4589     break;
4590   case ISD::FEXP:
4591   case ISD::STRICT_FEXP:
4592     ExpandFPLibCall(Node, RTLIB::EXP_F32, RTLIB::EXP_F64, RTLIB::EXP_F80,
4593                     RTLIB::EXP_F128, RTLIB::EXP_PPCF128, Results);
4594     break;
4595   case ISD::FEXP2:
4596   case ISD::STRICT_FEXP2:
4597     ExpandFPLibCall(Node, RTLIB::EXP2_F32, RTLIB::EXP2_F64, RTLIB::EXP2_F80,
4598                     RTLIB::EXP2_F128, RTLIB::EXP2_PPCF128, Results);
4599     break;
4600   case ISD::FEXP10:
4601     ExpandFPLibCall(Node, RTLIB::EXP10_F32, RTLIB::EXP10_F64, RTLIB::EXP10_F80,
4602                     RTLIB::EXP10_F128, RTLIB::EXP10_PPCF128, Results);
4603     break;
4604   case ISD::FTRUNC:
4605   case ISD::STRICT_FTRUNC:
4606     ExpandFPLibCall(Node, RTLIB::TRUNC_F32, RTLIB::TRUNC_F64,
4607                     RTLIB::TRUNC_F80, RTLIB::TRUNC_F128,
4608                     RTLIB::TRUNC_PPCF128, Results);
4609     break;
4610   case ISD::FFLOOR:
4611   case ISD::STRICT_FFLOOR:
4612     ExpandFPLibCall(Node, RTLIB::FLOOR_F32, RTLIB::FLOOR_F64,
4613                     RTLIB::FLOOR_F80, RTLIB::FLOOR_F128,
4614                     RTLIB::FLOOR_PPCF128, Results);
4615     break;
4616   case ISD::FCEIL:
4617   case ISD::STRICT_FCEIL:
4618     ExpandFPLibCall(Node, RTLIB::CEIL_F32, RTLIB::CEIL_F64,
4619                     RTLIB::CEIL_F80, RTLIB::CEIL_F128,
4620                     RTLIB::CEIL_PPCF128, Results);
4621     break;
4622   case ISD::FRINT:
4623   case ISD::STRICT_FRINT:
4624     ExpandFPLibCall(Node, RTLIB::RINT_F32, RTLIB::RINT_F64,
4625                     RTLIB::RINT_F80, RTLIB::RINT_F128,
4626                     RTLIB::RINT_PPCF128, Results);
4627     break;
4628   case ISD::FNEARBYINT:
4629   case ISD::STRICT_FNEARBYINT:
4630     ExpandFPLibCall(Node, RTLIB::NEARBYINT_F32,
4631                     RTLIB::NEARBYINT_F64,
4632                     RTLIB::NEARBYINT_F80,
4633                     RTLIB::NEARBYINT_F128,
4634                     RTLIB::NEARBYINT_PPCF128, Results);
4635     break;
4636   case ISD::FROUND:
4637   case ISD::STRICT_FROUND:
4638     ExpandFPLibCall(Node, RTLIB::ROUND_F32,
4639                     RTLIB::ROUND_F64,
4640                     RTLIB::ROUND_F80,
4641                     RTLIB::ROUND_F128,
4642                     RTLIB::ROUND_PPCF128, Results);
4643     break;
4644   case ISD::FROUNDEVEN:
4645   case ISD::STRICT_FROUNDEVEN:
4646     ExpandFPLibCall(Node, RTLIB::ROUNDEVEN_F32,
4647                     RTLIB::ROUNDEVEN_F64,
4648                     RTLIB::ROUNDEVEN_F80,
4649                     RTLIB::ROUNDEVEN_F128,
4650                     RTLIB::ROUNDEVEN_PPCF128, Results);
4651     break;
4652   case ISD::FLDEXP:
4653   case ISD::STRICT_FLDEXP:
4654     ExpandFPLibCall(Node, RTLIB::LDEXP_F32, RTLIB::LDEXP_F64, RTLIB::LDEXP_F80,
4655                     RTLIB::LDEXP_F128, RTLIB::LDEXP_PPCF128, Results);
4656     break;
4657   case ISD::FFREXP: {
4658     ExpandFrexpLibCall(Node, Results);
4659     break;
4660   }
4661   case ISD::FPOWI:
4662   case ISD::STRICT_FPOWI: {
4663     RTLIB::Libcall LC = RTLIB::getPOWI(Node->getSimpleValueType(0));
4664     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unexpected fpowi.");
4665     if (!TLI.getLibcallName(LC)) {
4666       // Some targets don't have a powi libcall; use pow instead.
4667       if (Node->isStrictFPOpcode()) {
4668         SDValue Exponent =
4669             DAG.getNode(ISD::STRICT_SINT_TO_FP, SDLoc(Node),
4670                         {Node->getValueType(0), Node->getValueType(1)},
4671                         {Node->getOperand(0), Node->getOperand(2)});
4672         SDValue FPOW =
4673             DAG.getNode(ISD::STRICT_FPOW, SDLoc(Node),
4674                         {Node->getValueType(0), Node->getValueType(1)},
4675                         {Exponent.getValue(1), Node->getOperand(1), Exponent});
4676         Results.push_back(FPOW);
4677         Results.push_back(FPOW.getValue(1));
4678       } else {
4679         SDValue Exponent =
4680             DAG.getNode(ISD::SINT_TO_FP, SDLoc(Node), Node->getValueType(0),
4681                         Node->getOperand(1));
4682         Results.push_back(DAG.getNode(ISD::FPOW, SDLoc(Node),
4683                                       Node->getValueType(0),
4684                                       Node->getOperand(0), Exponent));
4685       }
4686       break;
4687     }
4688     unsigned Offset = Node->isStrictFPOpcode() ? 1 : 0;
4689     bool ExponentHasSizeOfInt =
4690         DAG.getLibInfo().getIntSize() ==
4691         Node->getOperand(1 + Offset).getValueType().getSizeInBits();
4692     if (!ExponentHasSizeOfInt) {
4693       // If the exponent does not match with sizeof(int) a libcall to
4694       // RTLIB::POWI would use the wrong type for the argument.
4695       DAG.getContext()->emitError("POWI exponent does not match sizeof(int)");
4696       Results.push_back(DAG.getUNDEF(Node->getValueType(0)));
4697       break;
4698     }
4699     ExpandFPLibCall(Node, LC, Results);
4700     break;
4701   }
4702   case ISD::FPOW:
4703   case ISD::STRICT_FPOW:
4704     ExpandFPLibCall(Node, RTLIB::POW_F32, RTLIB::POW_F64, RTLIB::POW_F80,
4705                     RTLIB::POW_F128, RTLIB::POW_PPCF128, Results);
4706     break;
4707   case ISD::LROUND:
4708   case ISD::STRICT_LROUND:
4709     ExpandArgFPLibCall(Node, RTLIB::LROUND_F32,
4710                        RTLIB::LROUND_F64, RTLIB::LROUND_F80,
4711                        RTLIB::LROUND_F128,
4712                        RTLIB::LROUND_PPCF128, Results);
4713     break;
4714   case ISD::LLROUND:
4715   case ISD::STRICT_LLROUND:
4716     ExpandArgFPLibCall(Node, RTLIB::LLROUND_F32,
4717                        RTLIB::LLROUND_F64, RTLIB::LLROUND_F80,
4718                        RTLIB::LLROUND_F128,
4719                        RTLIB::LLROUND_PPCF128, Results);
4720     break;
4721   case ISD::LRINT:
4722   case ISD::STRICT_LRINT:
4723     ExpandArgFPLibCall(Node, RTLIB::LRINT_F32,
4724                        RTLIB::LRINT_F64, RTLIB::LRINT_F80,
4725                        RTLIB::LRINT_F128,
4726                        RTLIB::LRINT_PPCF128, Results);
4727     break;
4728   case ISD::LLRINT:
4729   case ISD::STRICT_LLRINT:
4730     ExpandArgFPLibCall(Node, RTLIB::LLRINT_F32,
4731                        RTLIB::LLRINT_F64, RTLIB::LLRINT_F80,
4732                        RTLIB::LLRINT_F128,
4733                        RTLIB::LLRINT_PPCF128, Results);
4734     break;
4735   case ISD::FDIV:
4736   case ISD::STRICT_FDIV:
4737     ExpandFPLibCall(Node, RTLIB::DIV_F32, RTLIB::DIV_F64,
4738                     RTLIB::DIV_F80, RTLIB::DIV_F128,
4739                     RTLIB::DIV_PPCF128, Results);
4740     break;
4741   case ISD::FREM:
4742   case ISD::STRICT_FREM:
4743     ExpandFPLibCall(Node, RTLIB::REM_F32, RTLIB::REM_F64,
4744                     RTLIB::REM_F80, RTLIB::REM_F128,
4745                     RTLIB::REM_PPCF128, Results);
4746     break;
4747   case ISD::FMA:
4748   case ISD::STRICT_FMA:
4749     ExpandFPLibCall(Node, RTLIB::FMA_F32, RTLIB::FMA_F64,
4750                     RTLIB::FMA_F80, RTLIB::FMA_F128,
4751                     RTLIB::FMA_PPCF128, Results);
4752     break;
4753   case ISD::FADD:
4754   case ISD::STRICT_FADD:
4755     ExpandFPLibCall(Node, RTLIB::ADD_F32, RTLIB::ADD_F64,
4756                     RTLIB::ADD_F80, RTLIB::ADD_F128,
4757                     RTLIB::ADD_PPCF128, Results);
4758     break;
4759   case ISD::FMUL:
4760   case ISD::STRICT_FMUL:
4761     ExpandFPLibCall(Node, RTLIB::MUL_F32, RTLIB::MUL_F64,
4762                     RTLIB::MUL_F80, RTLIB::MUL_F128,
4763                     RTLIB::MUL_PPCF128, Results);
4764     break;
4765   case ISD::FP16_TO_FP:
4766     if (Node->getValueType(0) == MVT::f32) {
4767       Results.push_back(ExpandLibCall(RTLIB::FPEXT_F16_F32, Node, false).first);
4768     }
4769     break;
4770   case ISD::STRICT_BF16_TO_FP:
4771     if (Node->getValueType(0) == MVT::f32) {
4772       TargetLowering::MakeLibCallOptions CallOptions;
4773       std::pair<SDValue, SDValue> Tmp = TLI.makeLibCall(
4774           DAG, RTLIB::FPEXT_BF16_F32, MVT::f32, Node->getOperand(1),
4775           CallOptions, SDLoc(Node), Node->getOperand(0));
4776       Results.push_back(Tmp.first);
4777       Results.push_back(Tmp.second);
4778     }
4779     break;
4780   case ISD::STRICT_FP16_TO_FP: {
4781     if (Node->getValueType(0) == MVT::f32) {
4782       TargetLowering::MakeLibCallOptions CallOptions;
4783       std::pair<SDValue, SDValue> Tmp = TLI.makeLibCall(
4784           DAG, RTLIB::FPEXT_F16_F32, MVT::f32, Node->getOperand(1), CallOptions,
4785           SDLoc(Node), Node->getOperand(0));
4786       Results.push_back(Tmp.first);
4787       Results.push_back(Tmp.second);
4788     }
4789     break;
4790   }
4791   case ISD::FP_TO_FP16: {
4792     RTLIB::Libcall LC =
4793         RTLIB::getFPROUND(Node->getOperand(0).getValueType(), MVT::f16);
4794     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unable to expand fp_to_fp16");
4795     Results.push_back(ExpandLibCall(LC, Node, false).first);
4796     break;
4797   }
4798   case ISD::FP_TO_BF16: {
4799     RTLIB::Libcall LC =
4800         RTLIB::getFPROUND(Node->getOperand(0).getValueType(), MVT::bf16);
4801     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unable to expand fp_to_bf16");
4802     Results.push_back(ExpandLibCall(LC, Node, false).first);
4803     break;
4804   }
4805   case ISD::STRICT_SINT_TO_FP:
4806   case ISD::STRICT_UINT_TO_FP:
4807   case ISD::SINT_TO_FP:
4808   case ISD::UINT_TO_FP: {
4809     // TODO - Common the code with DAGTypeLegalizer::SoftenFloatRes_XINT_TO_FP
4810     bool IsStrict = Node->isStrictFPOpcode();
4811     bool Signed = Node->getOpcode() == ISD::SINT_TO_FP ||
4812                   Node->getOpcode() == ISD::STRICT_SINT_TO_FP;
4813     EVT SVT = Node->getOperand(IsStrict ? 1 : 0).getValueType();
4814     EVT RVT = Node->getValueType(0);
4815     EVT NVT = EVT();
4816     SDLoc dl(Node);
4817 
4818     // Even if the input is legal, no libcall may exactly match, eg. we don't
4819     // have i1 -> fp conversions. So, it needs to be promoted to a larger type,
4820     // eg: i13 -> fp. Then, look for an appropriate libcall.
4821     RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
4822     for (unsigned t = MVT::FIRST_INTEGER_VALUETYPE;
4823          t <= MVT::LAST_INTEGER_VALUETYPE && LC == RTLIB::UNKNOWN_LIBCALL;
4824          ++t) {
4825       NVT = (MVT::SimpleValueType)t;
4826       // The source needs to big enough to hold the operand.
4827       if (NVT.bitsGE(SVT))
4828         LC = Signed ? RTLIB::getSINTTOFP(NVT, RVT)
4829                     : RTLIB::getUINTTOFP(NVT, RVT);
4830     }
4831     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unable to legalize as libcall");
4832 
4833     SDValue Chain = IsStrict ? Node->getOperand(0) : SDValue();
4834     // Sign/zero extend the argument if the libcall takes a larger type.
4835     SDValue Op = DAG.getNode(Signed ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND, dl,
4836                              NVT, Node->getOperand(IsStrict ? 1 : 0));
4837     TargetLowering::MakeLibCallOptions CallOptions;
4838     CallOptions.setSExt(Signed);
4839     std::pair<SDValue, SDValue> Tmp =
4840         TLI.makeLibCall(DAG, LC, RVT, Op, CallOptions, dl, Chain);
4841     Results.push_back(Tmp.first);
4842     if (IsStrict)
4843       Results.push_back(Tmp.second);
4844     break;
4845   }
4846   case ISD::FP_TO_SINT:
4847   case ISD::FP_TO_UINT:
4848   case ISD::STRICT_FP_TO_SINT:
4849   case ISD::STRICT_FP_TO_UINT: {
4850     // TODO - Common the code with DAGTypeLegalizer::SoftenFloatOp_FP_TO_XINT.
4851     bool IsStrict = Node->isStrictFPOpcode();
4852     bool Signed = Node->getOpcode() == ISD::FP_TO_SINT ||
4853                   Node->getOpcode() == ISD::STRICT_FP_TO_SINT;
4854 
4855     SDValue Op = Node->getOperand(IsStrict ? 1 : 0);
4856     EVT SVT = Op.getValueType();
4857     EVT RVT = Node->getValueType(0);
4858     EVT NVT = EVT();
4859     SDLoc dl(Node);
4860 
4861     // Even if the result is legal, no libcall may exactly match, eg. we don't
4862     // have fp -> i1 conversions. So, it needs to be promoted to a larger type,
4863     // eg: fp -> i32. Then, look for an appropriate libcall.
4864     RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
4865     for (unsigned IntVT = MVT::FIRST_INTEGER_VALUETYPE;
4866          IntVT <= MVT::LAST_INTEGER_VALUETYPE && LC == RTLIB::UNKNOWN_LIBCALL;
4867          ++IntVT) {
4868       NVT = (MVT::SimpleValueType)IntVT;
4869       // The type needs to big enough to hold the result.
4870       if (NVT.bitsGE(RVT))
4871         LC = Signed ? RTLIB::getFPTOSINT(SVT, NVT)
4872                     : RTLIB::getFPTOUINT(SVT, NVT);
4873     }
4874     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unable to legalize as libcall");
4875 
4876     SDValue Chain = IsStrict ? Node->getOperand(0) : SDValue();
4877     TargetLowering::MakeLibCallOptions CallOptions;
4878     std::pair<SDValue, SDValue> Tmp =
4879         TLI.makeLibCall(DAG, LC, NVT, Op, CallOptions, dl, Chain);
4880 
4881     // Truncate the result if the libcall returns a larger type.
4882     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, RVT, Tmp.first));
4883     if (IsStrict)
4884       Results.push_back(Tmp.second);
4885     break;
4886   }
4887 
4888   case ISD::FP_ROUND:
4889   case ISD::STRICT_FP_ROUND: {
4890     // X = FP_ROUND(Y, TRUNC)
4891     // TRUNC is a flag, which is always an integer that is zero or one.
4892     // If TRUNC is 0, this is a normal rounding, if it is 1, this FP_ROUND
4893     // is known to not change the value of Y.
4894     // We can only expand it into libcall if the TRUNC is 0.
4895     bool IsStrict = Node->isStrictFPOpcode();
4896     SDValue Op = Node->getOperand(IsStrict ? 1 : 0);
4897     SDValue Chain = IsStrict ? Node->getOperand(0) : SDValue();
4898     EVT VT = Node->getValueType(0);
4899     assert(cast<ConstantSDNode>(Node->getOperand(IsStrict ? 2 : 1))->isZero() &&
4900            "Unable to expand as libcall if it is not normal rounding");
4901 
4902     RTLIB::Libcall LC = RTLIB::getFPROUND(Op.getValueType(), VT);
4903     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unable to legalize as libcall");
4904 
4905     TargetLowering::MakeLibCallOptions CallOptions;
4906     std::pair<SDValue, SDValue> Tmp =
4907         TLI.makeLibCall(DAG, LC, VT, Op, CallOptions, SDLoc(Node), Chain);
4908     Results.push_back(Tmp.first);
4909     if (IsStrict)
4910       Results.push_back(Tmp.second);
4911     break;
4912   }
4913   case ISD::FP_EXTEND: {
4914     Results.push_back(
4915         ExpandLibCall(RTLIB::getFPEXT(Node->getOperand(0).getValueType(),
4916                                       Node->getValueType(0)),
4917                       Node, false).first);
4918     break;
4919   }
4920   case ISD::STRICT_FP_EXTEND:
4921   case ISD::STRICT_FP_TO_FP16:
4922   case ISD::STRICT_FP_TO_BF16: {
4923     RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
4924     if (Node->getOpcode() == ISD::STRICT_FP_TO_FP16)
4925       LC = RTLIB::getFPROUND(Node->getOperand(1).getValueType(), MVT::f16);
4926     else if (Node->getOpcode() == ISD::STRICT_FP_TO_BF16)
4927       LC = RTLIB::getFPROUND(Node->getOperand(1).getValueType(), MVT::bf16);
4928     else
4929       LC = RTLIB::getFPEXT(Node->getOperand(1).getValueType(),
4930                            Node->getValueType(0));
4931 
4932     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unable to legalize as libcall");
4933 
4934     TargetLowering::MakeLibCallOptions CallOptions;
4935     std::pair<SDValue, SDValue> Tmp =
4936         TLI.makeLibCall(DAG, LC, Node->getValueType(0), Node->getOperand(1),
4937                         CallOptions, SDLoc(Node), Node->getOperand(0));
4938     Results.push_back(Tmp.first);
4939     Results.push_back(Tmp.second);
4940     break;
4941   }
4942   case ISD::FSUB:
4943   case ISD::STRICT_FSUB:
4944     ExpandFPLibCall(Node, RTLIB::SUB_F32, RTLIB::SUB_F64,
4945                     RTLIB::SUB_F80, RTLIB::SUB_F128,
4946                     RTLIB::SUB_PPCF128, Results);
4947     break;
4948   case ISD::SREM:
4949     Results.push_back(ExpandIntLibCall(Node, true,
4950                                        RTLIB::SREM_I8,
4951                                        RTLIB::SREM_I16, RTLIB::SREM_I32,
4952                                        RTLIB::SREM_I64, RTLIB::SREM_I128));
4953     break;
4954   case ISD::UREM:
4955     Results.push_back(ExpandIntLibCall(Node, false,
4956                                        RTLIB::UREM_I8,
4957                                        RTLIB::UREM_I16, RTLIB::UREM_I32,
4958                                        RTLIB::UREM_I64, RTLIB::UREM_I128));
4959     break;
4960   case ISD::SDIV:
4961     Results.push_back(ExpandIntLibCall(Node, true,
4962                                        RTLIB::SDIV_I8,
4963                                        RTLIB::SDIV_I16, RTLIB::SDIV_I32,
4964                                        RTLIB::SDIV_I64, RTLIB::SDIV_I128));
4965     break;
4966   case ISD::UDIV:
4967     Results.push_back(ExpandIntLibCall(Node, false,
4968                                        RTLIB::UDIV_I8,
4969                                        RTLIB::UDIV_I16, RTLIB::UDIV_I32,
4970                                        RTLIB::UDIV_I64, RTLIB::UDIV_I128));
4971     break;
4972   case ISD::SDIVREM:
4973   case ISD::UDIVREM:
4974     // Expand into divrem libcall
4975     ExpandDivRemLibCall(Node, Results);
4976     break;
4977   case ISD::MUL:
4978     Results.push_back(ExpandIntLibCall(Node, false,
4979                                        RTLIB::MUL_I8,
4980                                        RTLIB::MUL_I16, RTLIB::MUL_I32,
4981                                        RTLIB::MUL_I64, RTLIB::MUL_I128));
4982     break;
4983   case ISD::CTLZ_ZERO_UNDEF:
4984     switch (Node->getSimpleValueType(0).SimpleTy) {
4985     default:
4986       llvm_unreachable("LibCall explicitly requested, but not available");
4987     case MVT::i32:
4988       Results.push_back(ExpandLibCall(RTLIB::CTLZ_I32, Node, false).first);
4989       break;
4990     case MVT::i64:
4991       Results.push_back(ExpandLibCall(RTLIB::CTLZ_I64, Node, false).first);
4992       break;
4993     case MVT::i128:
4994       Results.push_back(ExpandLibCall(RTLIB::CTLZ_I128, Node, false).first);
4995       break;
4996     }
4997     break;
4998   case ISD::RESET_FPENV: {
4999     // It is legalized to call 'fesetenv(FE_DFL_ENV)'. On most targets
5000     // FE_DFL_ENV is defined as '((const fenv_t *) -1)' in glibc.
5001     SDValue Ptr = DAG.getIntPtrConstant(-1LL, dl);
5002     SDValue Chain = Node->getOperand(0);
5003     Results.push_back(
5004         DAG.makeStateFunctionCall(RTLIB::FESETENV, Ptr, Chain, dl));
5005     break;
5006   }
5007   case ISD::GET_FPENV_MEM: {
5008     SDValue Chain = Node->getOperand(0);
5009     SDValue EnvPtr = Node->getOperand(1);
5010     Results.push_back(
5011         DAG.makeStateFunctionCall(RTLIB::FEGETENV, EnvPtr, Chain, dl));
5012     break;
5013   }
5014   case ISD::SET_FPENV_MEM: {
5015     SDValue Chain = Node->getOperand(0);
5016     SDValue EnvPtr = Node->getOperand(1);
5017     Results.push_back(
5018         DAG.makeStateFunctionCall(RTLIB::FESETENV, EnvPtr, Chain, dl));
5019     break;
5020   }
5021   case ISD::GET_FPMODE: {
5022     // Call fegetmode, which saves control modes into a stack slot. Then load
5023     // the value to return from the stack.
5024     EVT ModeVT = Node->getValueType(0);
5025     SDValue StackPtr = DAG.CreateStackTemporary(ModeVT);
5026     int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
5027     SDValue Chain = DAG.makeStateFunctionCall(RTLIB::FEGETMODE, StackPtr,
5028                                               Node->getOperand(0), dl);
5029     SDValue LdInst = DAG.getLoad(
5030         ModeVT, dl, Chain, StackPtr,
5031         MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI));
5032     Results.push_back(LdInst);
5033     Results.push_back(LdInst.getValue(1));
5034     break;
5035   }
5036   case ISD::SET_FPMODE: {
5037     // Move control modes to stack slot and then call fesetmode with the pointer
5038     // to the slot as argument.
5039     SDValue Mode = Node->getOperand(1);
5040     EVT ModeVT = Mode.getValueType();
5041     SDValue StackPtr = DAG.CreateStackTemporary(ModeVT);
5042     int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
5043     SDValue StInst = DAG.getStore(
5044         Node->getOperand(0), dl, Mode, StackPtr,
5045         MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI));
5046     Results.push_back(
5047         DAG.makeStateFunctionCall(RTLIB::FESETMODE, StackPtr, StInst, dl));
5048     break;
5049   }
5050   case ISD::RESET_FPMODE: {
5051     // It is legalized to a call 'fesetmode(FE_DFL_MODE)'. On most targets
5052     // FE_DFL_MODE is defined as '((const femode_t *) -1)' in glibc. If not, the
5053     // target must provide custom lowering.
5054     const DataLayout &DL = DAG.getDataLayout();
5055     EVT PtrTy = TLI.getPointerTy(DL);
5056     SDValue Mode = DAG.getConstant(-1LL, dl, PtrTy);
5057     Results.push_back(DAG.makeStateFunctionCall(RTLIB::FESETMODE, Mode,
5058                                                 Node->getOperand(0), dl));
5059     break;
5060   }
5061   }
5062 
5063   // Replace the original node with the legalized result.
5064   if (!Results.empty()) {
5065     LLVM_DEBUG(dbgs() << "Successfully converted node to libcall\n");
5066     ReplaceNode(Node, Results.data());
5067   } else
5068     LLVM_DEBUG(dbgs() << "Could not convert node to libcall\n");
5069 }
5070 
5071 // Determine the vector type to use in place of an original scalar element when
5072 // promoting equally sized vectors.
5073 static MVT getPromotedVectorElementType(const TargetLowering &TLI,
5074                                         MVT EltVT, MVT NewEltVT) {
5075   unsigned OldEltsPerNewElt = EltVT.getSizeInBits() / NewEltVT.getSizeInBits();
5076   MVT MidVT = OldEltsPerNewElt == 1
5077                   ? NewEltVT
5078                   : MVT::getVectorVT(NewEltVT, OldEltsPerNewElt);
5079   assert(TLI.isTypeLegal(MidVT) && "unexpected");
5080   return MidVT;
5081 }
5082 
5083 void SelectionDAGLegalize::PromoteNode(SDNode *Node) {
5084   LLVM_DEBUG(dbgs() << "Trying to promote node\n");
5085   SmallVector<SDValue, 8> Results;
5086   MVT OVT = Node->getSimpleValueType(0);
5087   if (Node->getOpcode() == ISD::UINT_TO_FP ||
5088       Node->getOpcode() == ISD::SINT_TO_FP ||
5089       Node->getOpcode() == ISD::SETCC ||
5090       Node->getOpcode() == ISD::EXTRACT_VECTOR_ELT ||
5091       Node->getOpcode() == ISD::INSERT_VECTOR_ELT) {
5092     OVT = Node->getOperand(0).getSimpleValueType();
5093   }
5094   if (Node->getOpcode() == ISD::ATOMIC_STORE ||
5095       Node->getOpcode() == ISD::STRICT_UINT_TO_FP ||
5096       Node->getOpcode() == ISD::STRICT_SINT_TO_FP ||
5097       Node->getOpcode() == ISD::STRICT_FSETCC ||
5098       Node->getOpcode() == ISD::STRICT_FSETCCS ||
5099       Node->getOpcode() == ISD::VP_REDUCE_FADD ||
5100       Node->getOpcode() == ISD::VP_REDUCE_FMUL ||
5101       Node->getOpcode() == ISD::VP_REDUCE_FMAX ||
5102       Node->getOpcode() == ISD::VP_REDUCE_FMIN ||
5103       Node->getOpcode() == ISD::VP_REDUCE_FMAXIMUM ||
5104       Node->getOpcode() == ISD::VP_REDUCE_FMINIMUM ||
5105       Node->getOpcode() == ISD::VP_REDUCE_SEQ_FADD)
5106     OVT = Node->getOperand(1).getSimpleValueType();
5107   if (Node->getOpcode() == ISD::BR_CC ||
5108       Node->getOpcode() == ISD::SELECT_CC)
5109     OVT = Node->getOperand(2).getSimpleValueType();
5110   MVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), OVT);
5111   SDLoc dl(Node);
5112   SDValue Tmp1, Tmp2, Tmp3, Tmp4;
5113   switch (Node->getOpcode()) {
5114   case ISD::CTTZ:
5115   case ISD::CTTZ_ZERO_UNDEF:
5116   case ISD::CTLZ:
5117   case ISD::CTPOP: {
5118     // Zero extend the argument unless its cttz, then use any_extend.
5119     if (Node->getOpcode() == ISD::CTTZ ||
5120         Node->getOpcode() == ISD::CTTZ_ZERO_UNDEF)
5121       Tmp1 = DAG.getNode(ISD::ANY_EXTEND, dl, NVT, Node->getOperand(0));
5122     else
5123       Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Node->getOperand(0));
5124 
5125     unsigned NewOpc = Node->getOpcode();
5126     if (NewOpc == ISD::CTTZ) {
5127       // The count is the same in the promoted type except if the original
5128       // value was zero.  This can be handled by setting the bit just off
5129       // the top of the original type.
5130       auto TopBit = APInt::getOneBitSet(NVT.getSizeInBits(),
5131                                         OVT.getSizeInBits());
5132       Tmp1 = DAG.getNode(ISD::OR, dl, NVT, Tmp1,
5133                          DAG.getConstant(TopBit, dl, NVT));
5134       NewOpc = ISD::CTTZ_ZERO_UNDEF;
5135     }
5136     // Perform the larger operation. For CTPOP and CTTZ_ZERO_UNDEF, this is
5137     // already the correct result.
5138     Tmp1 = DAG.getNode(NewOpc, dl, NVT, Tmp1);
5139     if (NewOpc == ISD::CTLZ) {
5140       // Tmp1 = Tmp1 - (sizeinbits(NVT) - sizeinbits(Old VT))
5141       Tmp1 = DAG.getNode(ISD::SUB, dl, NVT, Tmp1,
5142                           DAG.getConstant(NVT.getSizeInBits() -
5143                                           OVT.getSizeInBits(), dl, NVT));
5144     }
5145     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp1));
5146     break;
5147   }
5148   case ISD::CTLZ_ZERO_UNDEF: {
5149     // We know that the argument is unlikely to be zero, hence we can take a
5150     // different approach as compared to ISD::CTLZ
5151 
5152     // Any Extend the argument
5153     auto AnyExtendedNode =
5154         DAG.getNode(ISD::ANY_EXTEND, dl, NVT, Node->getOperand(0));
5155 
5156     // Tmp1 = Tmp1 << (sizeinbits(NVT) - sizeinbits(Old VT))
5157     auto ShiftConstant = DAG.getShiftAmountConstant(
5158         NVT.getSizeInBits() - OVT.getSizeInBits(), NVT, dl);
5159     auto LeftShiftResult =
5160         DAG.getNode(ISD::SHL, dl, NVT, AnyExtendedNode, ShiftConstant);
5161 
5162     // Perform the larger operation
5163     auto CTLZResult = DAG.getNode(Node->getOpcode(), dl, NVT, LeftShiftResult);
5164     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, CTLZResult));
5165     break;
5166   }
5167   case ISD::BITREVERSE:
5168   case ISD::BSWAP: {
5169     unsigned DiffBits = NVT.getSizeInBits() - OVT.getSizeInBits();
5170     Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Node->getOperand(0));
5171     Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
5172     Tmp1 = DAG.getNode(
5173         ISD::SRL, dl, NVT, Tmp1,
5174         DAG.getConstant(DiffBits, dl,
5175                         TLI.getShiftAmountTy(NVT, DAG.getDataLayout())));
5176 
5177     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp1));
5178     break;
5179   }
5180   case ISD::FP_TO_UINT:
5181   case ISD::STRICT_FP_TO_UINT:
5182   case ISD::FP_TO_SINT:
5183   case ISD::STRICT_FP_TO_SINT:
5184     PromoteLegalFP_TO_INT(Node, dl, Results);
5185     break;
5186   case ISD::FP_TO_UINT_SAT:
5187   case ISD::FP_TO_SINT_SAT:
5188     Results.push_back(PromoteLegalFP_TO_INT_SAT(Node, dl));
5189     break;
5190   case ISD::UINT_TO_FP:
5191   case ISD::STRICT_UINT_TO_FP:
5192   case ISD::SINT_TO_FP:
5193   case ISD::STRICT_SINT_TO_FP:
5194     PromoteLegalINT_TO_FP(Node, dl, Results);
5195     break;
5196   case ISD::VAARG: {
5197     SDValue Chain = Node->getOperand(0); // Get the chain.
5198     SDValue Ptr = Node->getOperand(1); // Get the pointer.
5199 
5200     unsigned TruncOp;
5201     if (OVT.isVector()) {
5202       TruncOp = ISD::BITCAST;
5203     } else {
5204       assert(OVT.isInteger()
5205         && "VAARG promotion is supported only for vectors or integer types");
5206       TruncOp = ISD::TRUNCATE;
5207     }
5208 
5209     // Perform the larger operation, then convert back
5210     Tmp1 = DAG.getVAArg(NVT, dl, Chain, Ptr, Node->getOperand(2),
5211              Node->getConstantOperandVal(3));
5212     Chain = Tmp1.getValue(1);
5213 
5214     Tmp2 = DAG.getNode(TruncOp, dl, OVT, Tmp1);
5215 
5216     // Modified the chain result - switch anything that used the old chain to
5217     // use the new one.
5218     DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), Tmp2);
5219     DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), Chain);
5220     if (UpdatedNodes) {
5221       UpdatedNodes->insert(Tmp2.getNode());
5222       UpdatedNodes->insert(Chain.getNode());
5223     }
5224     ReplacedNode(Node);
5225     break;
5226   }
5227   case ISD::MUL:
5228   case ISD::SDIV:
5229   case ISD::SREM:
5230   case ISD::UDIV:
5231   case ISD::UREM:
5232   case ISD::SMIN:
5233   case ISD::SMAX:
5234   case ISD::UMIN:
5235   case ISD::UMAX:
5236   case ISD::AND:
5237   case ISD::OR:
5238   case ISD::XOR: {
5239     unsigned ExtOp, TruncOp;
5240     if (OVT.isVector()) {
5241       ExtOp   = ISD::BITCAST;
5242       TruncOp = ISD::BITCAST;
5243     } else {
5244       assert(OVT.isInteger() && "Cannot promote logic operation");
5245 
5246       switch (Node->getOpcode()) {
5247       default:
5248         ExtOp = ISD::ANY_EXTEND;
5249         break;
5250       case ISD::SDIV:
5251       case ISD::SREM:
5252       case ISD::SMIN:
5253       case ISD::SMAX:
5254         ExtOp = ISD::SIGN_EXTEND;
5255         break;
5256       case ISD::UDIV:
5257       case ISD::UREM:
5258         ExtOp = ISD::ZERO_EXTEND;
5259         break;
5260       case ISD::UMIN:
5261       case ISD::UMAX:
5262         if (TLI.isSExtCheaperThanZExt(OVT, NVT))
5263           ExtOp = ISD::SIGN_EXTEND;
5264         else
5265           ExtOp = ISD::ZERO_EXTEND;
5266         break;
5267       }
5268       TruncOp = ISD::TRUNCATE;
5269     }
5270     // Promote each of the values to the new type.
5271     Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
5272     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
5273     // Perform the larger operation, then convert back
5274     Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2);
5275     Results.push_back(DAG.getNode(TruncOp, dl, OVT, Tmp1));
5276     break;
5277   }
5278   case ISD::UMUL_LOHI:
5279   case ISD::SMUL_LOHI: {
5280     // Promote to a multiply in a wider integer type.
5281     unsigned ExtOp = Node->getOpcode() == ISD::UMUL_LOHI ? ISD::ZERO_EXTEND
5282                                                          : ISD::SIGN_EXTEND;
5283     Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
5284     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
5285     Tmp1 = DAG.getNode(ISD::MUL, dl, NVT, Tmp1, Tmp2);
5286 
5287     auto &DL = DAG.getDataLayout();
5288     unsigned OriginalSize = OVT.getScalarSizeInBits();
5289     Tmp2 = DAG.getNode(
5290         ISD::SRL, dl, NVT, Tmp1,
5291         DAG.getConstant(OriginalSize, dl, TLI.getScalarShiftAmountTy(DL, NVT)));
5292     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp1));
5293     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp2));
5294     break;
5295   }
5296   case ISD::SELECT: {
5297     unsigned ExtOp, TruncOp;
5298     if (Node->getValueType(0).isVector() ||
5299         Node->getValueType(0).getSizeInBits() == NVT.getSizeInBits()) {
5300       ExtOp   = ISD::BITCAST;
5301       TruncOp = ISD::BITCAST;
5302     } else if (Node->getValueType(0).isInteger()) {
5303       ExtOp   = ISD::ANY_EXTEND;
5304       TruncOp = ISD::TRUNCATE;
5305     } else {
5306       ExtOp   = ISD::FP_EXTEND;
5307       TruncOp = ISD::FP_ROUND;
5308     }
5309     Tmp1 = Node->getOperand(0);
5310     // Promote each of the values to the new type.
5311     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
5312     Tmp3 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(2));
5313     // Perform the larger operation, then round down.
5314     Tmp1 = DAG.getSelect(dl, NVT, Tmp1, Tmp2, Tmp3);
5315     Tmp1->setFlags(Node->getFlags());
5316     if (TruncOp != ISD::FP_ROUND)
5317       Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1);
5318     else
5319       Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1,
5320                          DAG.getIntPtrConstant(0, dl));
5321     Results.push_back(Tmp1);
5322     break;
5323   }
5324   case ISD::VECTOR_SHUFFLE: {
5325     ArrayRef<int> Mask = cast<ShuffleVectorSDNode>(Node)->getMask();
5326 
5327     // Cast the two input vectors.
5328     Tmp1 = DAG.getNode(ISD::BITCAST, dl, NVT, Node->getOperand(0));
5329     Tmp2 = DAG.getNode(ISD::BITCAST, dl, NVT, Node->getOperand(1));
5330 
5331     // Convert the shuffle mask to the right # elements.
5332     Tmp1 = ShuffleWithNarrowerEltType(NVT, OVT, dl, Tmp1, Tmp2, Mask);
5333     Tmp1 = DAG.getNode(ISD::BITCAST, dl, OVT, Tmp1);
5334     Results.push_back(Tmp1);
5335     break;
5336   }
5337   case ISD::VECTOR_SPLICE: {
5338     Tmp1 = DAG.getNode(ISD::ANY_EXTEND, dl, NVT, Node->getOperand(0));
5339     Tmp2 = DAG.getNode(ISD::ANY_EXTEND, dl, NVT, Node->getOperand(1));
5340     Tmp3 = DAG.getNode(ISD::VECTOR_SPLICE, dl, NVT, Tmp1, Tmp2,
5341                        Node->getOperand(2));
5342     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp3));
5343     break;
5344   }
5345   case ISD::SELECT_CC: {
5346     SDValue Cond = Node->getOperand(4);
5347     ISD::CondCode CCCode = cast<CondCodeSDNode>(Cond)->get();
5348     // Type of the comparison operands.
5349     MVT CVT = Node->getSimpleValueType(0);
5350     assert(CVT == OVT && "not handled");
5351 
5352     unsigned ExtOp = ISD::FP_EXTEND;
5353     if (NVT.isInteger()) {
5354       ExtOp = isSignedIntSetCC(CCCode) ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND;
5355     }
5356 
5357     // Promote the comparison operands, if needed.
5358     if (TLI.isCondCodeLegal(CCCode, CVT)) {
5359       Tmp1 = Node->getOperand(0);
5360       Tmp2 = Node->getOperand(1);
5361     } else {
5362       Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
5363       Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
5364     }
5365     // Cast the true/false operands.
5366     Tmp3 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(2));
5367     Tmp4 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(3));
5368 
5369     Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, NVT, {Tmp1, Tmp2, Tmp3, Tmp4, Cond},
5370                        Node->getFlags());
5371 
5372     // Cast the result back to the original type.
5373     if (ExtOp != ISD::FP_EXTEND)
5374       Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp1);
5375     else
5376       Tmp1 = DAG.getNode(ISD::FP_ROUND, dl, OVT, Tmp1,
5377                          DAG.getIntPtrConstant(0, dl, /*isTarget=*/true));
5378 
5379     Results.push_back(Tmp1);
5380     break;
5381   }
5382   case ISD::SETCC:
5383   case ISD::STRICT_FSETCC:
5384   case ISD::STRICT_FSETCCS: {
5385     unsigned ExtOp = ISD::FP_EXTEND;
5386     if (NVT.isInteger()) {
5387       ISD::CondCode CCCode = cast<CondCodeSDNode>(Node->getOperand(2))->get();
5388       if (isSignedIntSetCC(CCCode) ||
5389           TLI.isSExtCheaperThanZExt(Node->getOperand(0).getValueType(), NVT))
5390         ExtOp = ISD::SIGN_EXTEND;
5391       else
5392         ExtOp = ISD::ZERO_EXTEND;
5393     }
5394     if (Node->isStrictFPOpcode()) {
5395       SDValue InChain = Node->getOperand(0);
5396       std::tie(Tmp1, std::ignore) =
5397           DAG.getStrictFPExtendOrRound(Node->getOperand(1), InChain, dl, NVT);
5398       std::tie(Tmp2, std::ignore) =
5399           DAG.getStrictFPExtendOrRound(Node->getOperand(2), InChain, dl, NVT);
5400       SmallVector<SDValue, 2> TmpChains = {Tmp1.getValue(1), Tmp2.getValue(1)};
5401       SDValue OutChain = DAG.getTokenFactor(dl, TmpChains);
5402       SDVTList VTs = DAG.getVTList(Node->getValueType(0), MVT::Other);
5403       Results.push_back(DAG.getNode(Node->getOpcode(), dl, VTs,
5404                                     {OutChain, Tmp1, Tmp2, Node->getOperand(3)},
5405                                     Node->getFlags()));
5406       Results.push_back(Results.back().getValue(1));
5407       break;
5408     }
5409     Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
5410     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
5411     Results.push_back(DAG.getNode(ISD::SETCC, dl, Node->getValueType(0), Tmp1,
5412                                   Tmp2, Node->getOperand(2), Node->getFlags()));
5413     break;
5414   }
5415   case ISD::BR_CC: {
5416     unsigned ExtOp = ISD::FP_EXTEND;
5417     if (NVT.isInteger()) {
5418       ISD::CondCode CCCode =
5419         cast<CondCodeSDNode>(Node->getOperand(1))->get();
5420       ExtOp = isSignedIntSetCC(CCCode) ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND;
5421     }
5422     Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(2));
5423     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(3));
5424     Results.push_back(DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0),
5425                                   Node->getOperand(0), Node->getOperand(1),
5426                                   Tmp1, Tmp2, Node->getOperand(4)));
5427     break;
5428   }
5429   case ISD::FADD:
5430   case ISD::FSUB:
5431   case ISD::FMUL:
5432   case ISD::FDIV:
5433   case ISD::FREM:
5434   case ISD::FMINNUM:
5435   case ISD::FMAXNUM:
5436   case ISD::FMINIMUM:
5437   case ISD::FMAXIMUM:
5438   case ISD::FPOW:
5439     Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
5440     Tmp2 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(1));
5441     Tmp3 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2,
5442                        Node->getFlags());
5443     Results.push_back(
5444         DAG.getNode(ISD::FP_ROUND, dl, OVT, Tmp3,
5445                     DAG.getIntPtrConstant(0, dl, /*isTarget=*/true)));
5446     break;
5447   case ISD::STRICT_FADD:
5448   case ISD::STRICT_FSUB:
5449   case ISD::STRICT_FMUL:
5450   case ISD::STRICT_FDIV:
5451   case ISD::STRICT_FMINNUM:
5452   case ISD::STRICT_FMAXNUM:
5453   case ISD::STRICT_FREM:
5454   case ISD::STRICT_FPOW:
5455     Tmp1 = DAG.getNode(ISD::STRICT_FP_EXTEND, dl, {NVT, MVT::Other},
5456                        {Node->getOperand(0), Node->getOperand(1)});
5457     Tmp2 = DAG.getNode(ISD::STRICT_FP_EXTEND, dl, {NVT, MVT::Other},
5458                        {Node->getOperand(0), Node->getOperand(2)});
5459     Tmp3 = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Tmp1.getValue(1),
5460                        Tmp2.getValue(1));
5461     Tmp1 = DAG.getNode(Node->getOpcode(), dl, {NVT, MVT::Other},
5462                        {Tmp3, Tmp1, Tmp2});
5463     Tmp1 = DAG.getNode(ISD::STRICT_FP_ROUND, dl, {OVT, MVT::Other},
5464                        {Tmp1.getValue(1), Tmp1, DAG.getIntPtrConstant(0, dl)});
5465     Results.push_back(Tmp1);
5466     Results.push_back(Tmp1.getValue(1));
5467     break;
5468   case ISD::FMA:
5469     Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
5470     Tmp2 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(1));
5471     Tmp3 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(2));
5472     Results.push_back(
5473         DAG.getNode(ISD::FP_ROUND, dl, OVT,
5474                     DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2, Tmp3),
5475                     DAG.getIntPtrConstant(0, dl, /*isTarget=*/true)));
5476     break;
5477   case ISD::STRICT_FMA:
5478     Tmp1 = DAG.getNode(ISD::STRICT_FP_EXTEND, dl, {NVT, MVT::Other},
5479                        {Node->getOperand(0), Node->getOperand(1)});
5480     Tmp2 = DAG.getNode(ISD::STRICT_FP_EXTEND, dl, {NVT, MVT::Other},
5481                        {Node->getOperand(0), Node->getOperand(2)});
5482     Tmp3 = DAG.getNode(ISD::STRICT_FP_EXTEND, dl, {NVT, MVT::Other},
5483                        {Node->getOperand(0), Node->getOperand(3)});
5484     Tmp4 = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Tmp1.getValue(1),
5485                        Tmp2.getValue(1), Tmp3.getValue(1));
5486     Tmp4 = DAG.getNode(Node->getOpcode(), dl, {NVT, MVT::Other},
5487                        {Tmp4, Tmp1, Tmp2, Tmp3});
5488     Tmp4 = DAG.getNode(ISD::STRICT_FP_ROUND, dl, {OVT, MVT::Other},
5489                        {Tmp4.getValue(1), Tmp4, DAG.getIntPtrConstant(0, dl)});
5490     Results.push_back(Tmp4);
5491     Results.push_back(Tmp4.getValue(1));
5492     break;
5493   case ISD::FCOPYSIGN:
5494   case ISD::FLDEXP:
5495   case ISD::FPOWI: {
5496     Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
5497     Tmp2 = Node->getOperand(1);
5498     Tmp3 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2);
5499 
5500     // fcopysign doesn't change anything but the sign bit, so
5501     //   (fp_round (fcopysign (fpext a), b))
5502     // is as precise as
5503     //   (fp_round (fpext a))
5504     // which is a no-op. Mark it as a TRUNCating FP_ROUND.
5505     const bool isTrunc = (Node->getOpcode() == ISD::FCOPYSIGN);
5506     Results.push_back(
5507         DAG.getNode(ISD::FP_ROUND, dl, OVT, Tmp3,
5508                     DAG.getIntPtrConstant(isTrunc, dl, /*isTarget=*/true)));
5509     break;
5510   }
5511   case ISD::STRICT_FPOWI:
5512     Tmp1 = DAG.getNode(ISD::STRICT_FP_EXTEND, dl, {NVT, MVT::Other},
5513                        {Node->getOperand(0), Node->getOperand(1)});
5514     Tmp2 = DAG.getNode(Node->getOpcode(), dl, {NVT, MVT::Other},
5515                        {Tmp1.getValue(1), Tmp1, Node->getOperand(2)});
5516     Tmp3 = DAG.getNode(ISD::STRICT_FP_ROUND, dl, {OVT, MVT::Other},
5517                        {Tmp2.getValue(1), Tmp2, DAG.getIntPtrConstant(0, dl)});
5518     Results.push_back(Tmp3);
5519     Results.push_back(Tmp3.getValue(1));
5520     break;
5521   case ISD::FFREXP: {
5522     Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
5523     Tmp2 = DAG.getNode(ISD::FFREXP, dl, {NVT, Node->getValueType(1)}, Tmp1);
5524 
5525     Results.push_back(
5526         DAG.getNode(ISD::FP_ROUND, dl, OVT, Tmp2,
5527                     DAG.getIntPtrConstant(0, dl, /*isTarget=*/true)));
5528 
5529     Results.push_back(Tmp2.getValue(1));
5530     break;
5531   }
5532   case ISD::FFLOOR:
5533   case ISD::FCEIL:
5534   case ISD::FRINT:
5535   case ISD::FNEARBYINT:
5536   case ISD::FROUND:
5537   case ISD::FROUNDEVEN:
5538   case ISD::FTRUNC:
5539   case ISD::FNEG:
5540   case ISD::FSQRT:
5541   case ISD::FSIN:
5542   case ISD::FCOS:
5543   case ISD::FTAN:
5544   case ISD::FASIN:
5545   case ISD::FACOS:
5546   case ISD::FATAN:
5547   case ISD::FSINH:
5548   case ISD::FCOSH:
5549   case ISD::FTANH:
5550   case ISD::FLOG:
5551   case ISD::FLOG2:
5552   case ISD::FLOG10:
5553   case ISD::FABS:
5554   case ISD::FEXP:
5555   case ISD::FEXP2:
5556   case ISD::FEXP10:
5557   case ISD::FCANONICALIZE:
5558     Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
5559     Tmp2 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
5560     Results.push_back(
5561         DAG.getNode(ISD::FP_ROUND, dl, OVT, Tmp2,
5562                     DAG.getIntPtrConstant(0, dl, /*isTarget=*/true)));
5563     break;
5564   case ISD::STRICT_FFLOOR:
5565   case ISD::STRICT_FCEIL:
5566   case ISD::STRICT_FRINT:
5567   case ISD::STRICT_FNEARBYINT:
5568   case ISD::STRICT_FROUND:
5569   case ISD::STRICT_FROUNDEVEN:
5570   case ISD::STRICT_FTRUNC:
5571   case ISD::STRICT_FSQRT:
5572   case ISD::STRICT_FSIN:
5573   case ISD::STRICT_FCOS:
5574   case ISD::STRICT_FTAN:
5575   case ISD::STRICT_FASIN:
5576   case ISD::STRICT_FACOS:
5577   case ISD::STRICT_FATAN:
5578   case ISD::STRICT_FSINH:
5579   case ISD::STRICT_FCOSH:
5580   case ISD::STRICT_FTANH:
5581   case ISD::STRICT_FLOG:
5582   case ISD::STRICT_FLOG2:
5583   case ISD::STRICT_FLOG10:
5584   case ISD::STRICT_FEXP:
5585   case ISD::STRICT_FEXP2:
5586     Tmp1 = DAG.getNode(ISD::STRICT_FP_EXTEND, dl, {NVT, MVT::Other},
5587                        {Node->getOperand(0), Node->getOperand(1)});
5588     Tmp2 = DAG.getNode(Node->getOpcode(), dl, {NVT, MVT::Other},
5589                        {Tmp1.getValue(1), Tmp1});
5590     Tmp3 = DAG.getNode(ISD::STRICT_FP_ROUND, dl, {OVT, MVT::Other},
5591                        {Tmp2.getValue(1), Tmp2, DAG.getIntPtrConstant(0, dl)});
5592     Results.push_back(Tmp3);
5593     Results.push_back(Tmp3.getValue(1));
5594     break;
5595   case ISD::BUILD_VECTOR: {
5596     MVT EltVT = OVT.getVectorElementType();
5597     MVT NewEltVT = NVT.getVectorElementType();
5598 
5599     // Handle bitcasts to a different vector type with the same total bit size
5600     //
5601     // e.g. v2i64 = build_vector i64:x, i64:y => v4i32
5602     //  =>
5603     //  v4i32 = concat_vectors (v2i32 (bitcast i64:x)), (v2i32 (bitcast i64:y))
5604 
5605     assert(NVT.isVector() && OVT.getSizeInBits() == NVT.getSizeInBits() &&
5606            "Invalid promote type for build_vector");
5607     assert(NewEltVT.bitsLE(EltVT) && "not handled");
5608 
5609     MVT MidVT = getPromotedVectorElementType(TLI, EltVT, NewEltVT);
5610 
5611     SmallVector<SDValue, 8> NewOps;
5612     for (const SDValue &Op : Node->op_values())
5613       NewOps.push_back(DAG.getNode(ISD::BITCAST, SDLoc(Op), MidVT, Op));
5614 
5615     SDLoc SL(Node);
5616     SDValue Concat =
5617         DAG.getNode(MidVT == NewEltVT ? ISD::BUILD_VECTOR : ISD::CONCAT_VECTORS,
5618                     SL, NVT, NewOps);
5619     SDValue CvtVec = DAG.getNode(ISD::BITCAST, SL, OVT, Concat);
5620     Results.push_back(CvtVec);
5621     break;
5622   }
5623   case ISD::EXTRACT_VECTOR_ELT: {
5624     MVT EltVT = OVT.getVectorElementType();
5625     MVT NewEltVT = NVT.getVectorElementType();
5626 
5627     // Handle bitcasts to a different vector type with the same total bit size.
5628     //
5629     // e.g. v2i64 = extract_vector_elt x:v2i64, y:i32
5630     //  =>
5631     //  v4i32:castx = bitcast x:v2i64
5632     //
5633     // i64 = bitcast
5634     //   (v2i32 build_vector (i32 (extract_vector_elt castx, (2 * y))),
5635     //                       (i32 (extract_vector_elt castx, (2 * y + 1)))
5636     //
5637 
5638     assert(NVT.isVector() && OVT.getSizeInBits() == NVT.getSizeInBits() &&
5639            "Invalid promote type for extract_vector_elt");
5640     assert(NewEltVT.bitsLT(EltVT) && "not handled");
5641 
5642     MVT MidVT = getPromotedVectorElementType(TLI, EltVT, NewEltVT);
5643     unsigned NewEltsPerOldElt = MidVT.getVectorNumElements();
5644 
5645     SDValue Idx = Node->getOperand(1);
5646     EVT IdxVT = Idx.getValueType();
5647     SDLoc SL(Node);
5648     SDValue Factor = DAG.getConstant(NewEltsPerOldElt, SL, IdxVT);
5649     SDValue NewBaseIdx = DAG.getNode(ISD::MUL, SL, IdxVT, Idx, Factor);
5650 
5651     SDValue CastVec = DAG.getNode(ISD::BITCAST, SL, NVT, Node->getOperand(0));
5652 
5653     SmallVector<SDValue, 8> NewOps;
5654     for (unsigned I = 0; I < NewEltsPerOldElt; ++I) {
5655       SDValue IdxOffset = DAG.getConstant(I, SL, IdxVT);
5656       SDValue TmpIdx = DAG.getNode(ISD::ADD, SL, IdxVT, NewBaseIdx, IdxOffset);
5657 
5658       SDValue Elt = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, NewEltVT,
5659                                 CastVec, TmpIdx);
5660       NewOps.push_back(Elt);
5661     }
5662 
5663     SDValue NewVec = DAG.getBuildVector(MidVT, SL, NewOps);
5664     Results.push_back(DAG.getNode(ISD::BITCAST, SL, EltVT, NewVec));
5665     break;
5666   }
5667   case ISD::INSERT_VECTOR_ELT: {
5668     MVT EltVT = OVT.getVectorElementType();
5669     MVT NewEltVT = NVT.getVectorElementType();
5670 
5671     // Handle bitcasts to a different vector type with the same total bit size
5672     //
5673     // e.g. v2i64 = insert_vector_elt x:v2i64, y:i64, z:i32
5674     //  =>
5675     //  v4i32:castx = bitcast x:v2i64
5676     //  v2i32:casty = bitcast y:i64
5677     //
5678     // v2i64 = bitcast
5679     //   (v4i32 insert_vector_elt
5680     //       (v4i32 insert_vector_elt v4i32:castx,
5681     //                                (extract_vector_elt casty, 0), 2 * z),
5682     //        (extract_vector_elt casty, 1), (2 * z + 1))
5683 
5684     assert(NVT.isVector() && OVT.getSizeInBits() == NVT.getSizeInBits() &&
5685            "Invalid promote type for insert_vector_elt");
5686     assert(NewEltVT.bitsLT(EltVT) && "not handled");
5687 
5688     MVT MidVT = getPromotedVectorElementType(TLI, EltVT, NewEltVT);
5689     unsigned NewEltsPerOldElt = MidVT.getVectorNumElements();
5690 
5691     SDValue Val = Node->getOperand(1);
5692     SDValue Idx = Node->getOperand(2);
5693     EVT IdxVT = Idx.getValueType();
5694     SDLoc SL(Node);
5695 
5696     SDValue Factor = DAG.getConstant(NewEltsPerOldElt, SDLoc(), IdxVT);
5697     SDValue NewBaseIdx = DAG.getNode(ISD::MUL, SL, IdxVT, Idx, Factor);
5698 
5699     SDValue CastVec = DAG.getNode(ISD::BITCAST, SL, NVT, Node->getOperand(0));
5700     SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, MidVT, Val);
5701 
5702     SDValue NewVec = CastVec;
5703     for (unsigned I = 0; I < NewEltsPerOldElt; ++I) {
5704       SDValue IdxOffset = DAG.getConstant(I, SL, IdxVT);
5705       SDValue InEltIdx = DAG.getNode(ISD::ADD, SL, IdxVT, NewBaseIdx, IdxOffset);
5706 
5707       SDValue Elt = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, NewEltVT,
5708                                 CastVal, IdxOffset);
5709 
5710       NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, SL, NVT,
5711                            NewVec, Elt, InEltIdx);
5712     }
5713 
5714     Results.push_back(DAG.getNode(ISD::BITCAST, SL, OVT, NewVec));
5715     break;
5716   }
5717   case ISD::SCALAR_TO_VECTOR: {
5718     MVT EltVT = OVT.getVectorElementType();
5719     MVT NewEltVT = NVT.getVectorElementType();
5720 
5721     // Handle bitcasts to different vector type with the same total bit size.
5722     //
5723     // e.g. v2i64 = scalar_to_vector x:i64
5724     //   =>
5725     //  concat_vectors (v2i32 bitcast x:i64), (v2i32 undef)
5726     //
5727 
5728     MVT MidVT = getPromotedVectorElementType(TLI, EltVT, NewEltVT);
5729     SDValue Val = Node->getOperand(0);
5730     SDLoc SL(Node);
5731 
5732     SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, MidVT, Val);
5733     SDValue Undef = DAG.getUNDEF(MidVT);
5734 
5735     SmallVector<SDValue, 8> NewElts;
5736     NewElts.push_back(CastVal);
5737     for (unsigned I = 1, NElts = OVT.getVectorNumElements(); I != NElts; ++I)
5738       NewElts.push_back(Undef);
5739 
5740     SDValue Concat = DAG.getNode(ISD::CONCAT_VECTORS, SL, NVT, NewElts);
5741     SDValue CvtVec = DAG.getNode(ISD::BITCAST, SL, OVT, Concat);
5742     Results.push_back(CvtVec);
5743     break;
5744   }
5745   case ISD::ATOMIC_SWAP:
5746   case ISD::ATOMIC_STORE: {
5747     AtomicSDNode *AM = cast<AtomicSDNode>(Node);
5748     SDLoc SL(Node);
5749     SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, NVT, AM->getVal());
5750     assert(NVT.getSizeInBits() == OVT.getSizeInBits() &&
5751            "unexpected promotion type");
5752     assert(AM->getMemoryVT().getSizeInBits() == NVT.getSizeInBits() &&
5753            "unexpected atomic_swap with illegal type");
5754 
5755     SDValue Op0 = AM->getBasePtr();
5756     SDValue Op1 = CastVal;
5757 
5758     // ATOMIC_STORE uses a swapped operand order from every other AtomicSDNode,
5759     // but really it should merge with ISD::STORE.
5760     if (AM->getOpcode() == ISD::ATOMIC_STORE)
5761       std::swap(Op0, Op1);
5762 
5763     SDValue NewAtomic = DAG.getAtomic(AM->getOpcode(), SL, NVT, AM->getChain(),
5764                                       Op0, Op1, AM->getMemOperand());
5765 
5766     if (AM->getOpcode() != ISD::ATOMIC_STORE) {
5767       Results.push_back(DAG.getNode(ISD::BITCAST, SL, OVT, NewAtomic));
5768       Results.push_back(NewAtomic.getValue(1));
5769     } else
5770       Results.push_back(NewAtomic);
5771     break;
5772   }
5773   case ISD::ATOMIC_LOAD: {
5774     AtomicSDNode *AM = cast<AtomicSDNode>(Node);
5775     SDLoc SL(Node);
5776     assert(NVT.getSizeInBits() == OVT.getSizeInBits() &&
5777            "unexpected promotion type");
5778     assert(AM->getMemoryVT().getSizeInBits() == NVT.getSizeInBits() &&
5779            "unexpected atomic_load with illegal type");
5780 
5781     SDValue NewAtomic =
5782         DAG.getAtomic(ISD::ATOMIC_LOAD, SL, NVT, DAG.getVTList(NVT, MVT::Other),
5783                       {AM->getChain(), AM->getBasePtr()}, AM->getMemOperand());
5784     Results.push_back(DAG.getNode(ISD::BITCAST, SL, OVT, NewAtomic));
5785     Results.push_back(NewAtomic.getValue(1));
5786     break;
5787   }
5788   case ISD::SPLAT_VECTOR: {
5789     SDValue Scalar = Node->getOperand(0);
5790     MVT ScalarType = Scalar.getSimpleValueType();
5791     MVT NewScalarType = NVT.getVectorElementType();
5792     if (ScalarType.isInteger()) {
5793       Tmp1 = DAG.getNode(ISD::ANY_EXTEND, dl, NewScalarType, Scalar);
5794       Tmp2 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
5795       Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp2));
5796       break;
5797     }
5798     Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NewScalarType, Scalar);
5799     Tmp2 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
5800     Results.push_back(
5801         DAG.getNode(ISD::FP_ROUND, dl, OVT, Tmp2,
5802                     DAG.getIntPtrConstant(0, dl, /*isTarget=*/true)));
5803     break;
5804   }
5805   case ISD::VP_REDUCE_FADD:
5806   case ISD::VP_REDUCE_FMUL:
5807   case ISD::VP_REDUCE_FMAX:
5808   case ISD::VP_REDUCE_FMIN:
5809   case ISD::VP_REDUCE_FMAXIMUM:
5810   case ISD::VP_REDUCE_FMINIMUM:
5811   case ISD::VP_REDUCE_SEQ_FADD:
5812     Results.push_back(PromoteReduction(Node));
5813     break;
5814   }
5815 
5816   // Replace the original node with the legalized result.
5817   if (!Results.empty()) {
5818     LLVM_DEBUG(dbgs() << "Successfully promoted node\n");
5819     ReplaceNode(Node, Results.data());
5820   } else
5821     LLVM_DEBUG(dbgs() << "Could not promote node\n");
5822 }
5823 
5824 /// This is the entry point for the file.
5825 void SelectionDAG::Legalize() {
5826   AssignTopologicalOrder();
5827 
5828   SmallPtrSet<SDNode *, 16> LegalizedNodes;
5829   // Use a delete listener to remove nodes which were deleted during
5830   // legalization from LegalizeNodes. This is needed to handle the situation
5831   // where a new node is allocated by the object pool to the same address of a
5832   // previously deleted node.
5833   DAGNodeDeletedListener DeleteListener(
5834       *this,
5835       [&LegalizedNodes](SDNode *N, SDNode *E) { LegalizedNodes.erase(N); });
5836 
5837   SelectionDAGLegalize Legalizer(*this, LegalizedNodes);
5838 
5839   // Visit all the nodes. We start in topological order, so that we see
5840   // nodes with their original operands intact. Legalization can produce
5841   // new nodes which may themselves need to be legalized. Iterate until all
5842   // nodes have been legalized.
5843   while (true) {
5844     bool AnyLegalized = false;
5845     for (auto NI = allnodes_end(); NI != allnodes_begin();) {
5846       --NI;
5847 
5848       SDNode *N = &*NI;
5849       if (N->use_empty() && N != getRoot().getNode()) {
5850         ++NI;
5851         DeleteNode(N);
5852         continue;
5853       }
5854 
5855       if (LegalizedNodes.insert(N).second) {
5856         AnyLegalized = true;
5857         Legalizer.LegalizeOp(N);
5858 
5859         if (N->use_empty() && N != getRoot().getNode()) {
5860           ++NI;
5861           DeleteNode(N);
5862         }
5863       }
5864     }
5865     if (!AnyLegalized)
5866       break;
5867 
5868   }
5869 
5870   // Remove dead nodes now.
5871   RemoveDeadNodes();
5872 }
5873 
5874 bool SelectionDAG::LegalizeOp(SDNode *N,
5875                               SmallSetVector<SDNode *, 16> &UpdatedNodes) {
5876   SmallPtrSet<SDNode *, 16> LegalizedNodes;
5877   SelectionDAGLegalize Legalizer(*this, LegalizedNodes, &UpdatedNodes);
5878 
5879   // Directly insert the node in question, and legalize it. This will recurse
5880   // as needed through operands.
5881   LegalizedNodes.insert(N);
5882   Legalizer.LegalizeOp(N);
5883 
5884   return LegalizedNodes.count(N);
5885 }
5886