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/SetVector.h"
17 #include "llvm/ADT/SmallPtrSet.h"
18 #include "llvm/ADT/SmallSet.h"
19 #include "llvm/ADT/SmallVector.h"
20 #include "llvm/Analysis/TargetLibraryInfo.h"
21 #include "llvm/CodeGen/ISDOpcodes.h"
22 #include "llvm/CodeGen/MachineFunction.h"
23 #include "llvm/CodeGen/MachineJumpTableInfo.h"
24 #include "llvm/CodeGen/MachineMemOperand.h"
25 #include "llvm/CodeGen/RuntimeLibcalls.h"
26 #include "llvm/CodeGen/SelectionDAG.h"
27 #include "llvm/CodeGen/SelectionDAGNodes.h"
28 #include "llvm/CodeGen/TargetFrameLowering.h"
29 #include "llvm/CodeGen/TargetLowering.h"
30 #include "llvm/CodeGen/TargetSubtargetInfo.h"
31 #include "llvm/CodeGen/ValueTypes.h"
32 #include "llvm/IR/CallingConv.h"
33 #include "llvm/IR/Constants.h"
34 #include "llvm/IR/DataLayout.h"
35 #include "llvm/IR/DerivedTypes.h"
36 #include "llvm/IR/Function.h"
37 #include "llvm/IR/Metadata.h"
38 #include "llvm/IR/Type.h"
39 #include "llvm/Support/Casting.h"
40 #include "llvm/Support/Compiler.h"
41 #include "llvm/Support/Debug.h"
42 #include "llvm/Support/ErrorHandling.h"
43 #include "llvm/Support/MachineValueType.h"
44 #include "llvm/Support/MathExtras.h"
45 #include "llvm/Support/raw_ostream.h"
46 #include "llvm/Target/TargetMachine.h"
47 #include "llvm/Target/TargetOptions.h"
48 #include <algorithm>
49 #include <cassert>
50 #include <cstdint>
51 #include <tuple>
52 #include <utility>
53 
54 using namespace llvm;
55 
56 #define DEBUG_TYPE "legalizedag"
57 
58 namespace {
59 
60 /// Keeps track of state when getting the sign of a floating-point value as an
61 /// integer.
62 struct FloatSignAsInt {
63   EVT FloatVT;
64   SDValue Chain;
65   SDValue FloatPtr;
66   SDValue IntPtr;
67   MachinePointerInfo IntPointerInfo;
68   MachinePointerInfo FloatPointerInfo;
69   SDValue IntValue;
70   APInt SignMask;
71   uint8_t SignBit;
72 };
73 
74 //===----------------------------------------------------------------------===//
75 /// This takes an arbitrary SelectionDAG as input and
76 /// hacks on it until the target machine can handle it.  This involves
77 /// eliminating value sizes the machine cannot handle (promoting small sizes to
78 /// large sizes or splitting up large values into small values) as well as
79 /// eliminating operations the machine cannot handle.
80 ///
81 /// This code also does a small amount of optimization and recognition of idioms
82 /// as part of its processing.  For example, if a target does not support a
83 /// 'setcc' instruction efficiently, but does support 'brcc' instruction, this
84 /// will attempt merge setcc and brc instructions into brcc's.
85 class SelectionDAGLegalize {
86   const TargetMachine &TM;
87   const TargetLowering &TLI;
88   SelectionDAG &DAG;
89 
90   /// The set of nodes which have already been legalized. We hold a
91   /// reference to it in order to update as necessary on node deletion.
92   SmallPtrSetImpl<SDNode *> &LegalizedNodes;
93 
94   /// A set of all the nodes updated during legalization.
95   SmallSetVector<SDNode *, 16> *UpdatedNodes;
96 
97   EVT getSetCCResultType(EVT VT) const {
98     return TLI.getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
99   }
100 
101   // Libcall insertion helpers.
102 
103 public:
104   SelectionDAGLegalize(SelectionDAG &DAG,
105                        SmallPtrSetImpl<SDNode *> &LegalizedNodes,
106                        SmallSetVector<SDNode *, 16> *UpdatedNodes = nullptr)
107       : TM(DAG.getTarget()), TLI(DAG.getTargetLoweringInfo()), DAG(DAG),
108         LegalizedNodes(LegalizedNodes), UpdatedNodes(UpdatedNodes) {}
109 
110   /// Legalizes the given operation.
111   void LegalizeOp(SDNode *Node);
112 
113 private:
114   SDValue OptimizeFloatStore(StoreSDNode *ST);
115 
116   void LegalizeLoadOps(SDNode *Node);
117   void LegalizeStoreOps(SDNode *Node);
118 
119   /// Some targets cannot handle a variable
120   /// insertion index for the INSERT_VECTOR_ELT instruction.  In this case, it
121   /// is necessary to spill the vector being inserted into to memory, perform
122   /// the insert there, and then read the result back.
123   SDValue PerformInsertVectorEltInMemory(SDValue Vec, SDValue Val, SDValue Idx,
124                                          const SDLoc &dl);
125   SDValue ExpandINSERT_VECTOR_ELT(SDValue Vec, SDValue Val, SDValue Idx,
126                                   const SDLoc &dl);
127 
128   /// Return a vector shuffle operation which
129   /// performs the same shuffe in terms of order or result bytes, but on a type
130   /// whose vector element type is narrower than the original shuffle type.
131   /// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
132   SDValue ShuffleWithNarrowerEltType(EVT NVT, EVT VT, const SDLoc &dl,
133                                      SDValue N1, SDValue N2,
134                                      ArrayRef<int> Mask) const;
135 
136   bool LegalizeSetCCCondCode(EVT VT, SDValue &LHS, SDValue &RHS, SDValue &CC,
137                              bool &NeedInvert, const SDLoc &dl, SDValue &Chain,
138                              bool IsSignaling = false);
139 
140   SDValue ExpandLibCall(RTLIB::Libcall LC, SDNode *Node, bool isSigned);
141 
142   void ExpandFPLibCall(SDNode *Node, RTLIB::Libcall Call_F32,
143                        RTLIB::Libcall Call_F64, RTLIB::Libcall Call_F80,
144                        RTLIB::Libcall Call_F128,
145                        RTLIB::Libcall Call_PPCF128,
146                        SmallVectorImpl<SDValue> &Results);
147   SDValue ExpandIntLibCall(SDNode *Node, bool isSigned,
148                            RTLIB::Libcall Call_I8,
149                            RTLIB::Libcall Call_I16,
150                            RTLIB::Libcall Call_I32,
151                            RTLIB::Libcall Call_I64,
152                            RTLIB::Libcall Call_I128);
153   void ExpandArgFPLibCall(SDNode *Node,
154                           RTLIB::Libcall Call_F32, RTLIB::Libcall Call_F64,
155                           RTLIB::Libcall Call_F80, RTLIB::Libcall Call_F128,
156                           RTLIB::Libcall Call_PPCF128,
157                           SmallVectorImpl<SDValue> &Results);
158   void ExpandDivRemLibCall(SDNode *Node, SmallVectorImpl<SDValue> &Results);
159   void ExpandSinCosLibCall(SDNode *Node, SmallVectorImpl<SDValue> &Results);
160 
161   SDValue EmitStackConvert(SDValue SrcOp, EVT SlotVT, EVT DestVT,
162                            const SDLoc &dl);
163   SDValue EmitStackConvert(SDValue SrcOp, EVT SlotVT, EVT DestVT,
164                            const SDLoc &dl, SDValue ChainIn);
165   SDValue ExpandBUILD_VECTOR(SDNode *Node);
166   SDValue ExpandSPLAT_VECTOR(SDNode *Node);
167   SDValue ExpandSCALAR_TO_VECTOR(SDNode *Node);
168   void ExpandDYNAMIC_STACKALLOC(SDNode *Node,
169                                 SmallVectorImpl<SDValue> &Results);
170   void getSignAsIntValue(FloatSignAsInt &State, const SDLoc &DL,
171                          SDValue Value) const;
172   SDValue modifySignAsInt(const FloatSignAsInt &State, const SDLoc &DL,
173                           SDValue NewIntValue) const;
174   SDValue ExpandFCOPYSIGN(SDNode *Node) const;
175   SDValue ExpandFABS(SDNode *Node) const;
176   SDValue ExpandFNEG(SDNode *Node) const;
177   SDValue ExpandLegalINT_TO_FP(SDNode *Node, SDValue &Chain);
178   void PromoteLegalINT_TO_FP(SDNode *N, const SDLoc &dl,
179                              SmallVectorImpl<SDValue> &Results);
180   void PromoteLegalFP_TO_INT(SDNode *N, const SDLoc &dl,
181                              SmallVectorImpl<SDValue> &Results);
182   SDValue PromoteLegalFP_TO_INT_SAT(SDNode *Node, const SDLoc &dl);
183 
184   SDValue ExpandBITREVERSE(SDValue Op, const SDLoc &dl);
185   SDValue ExpandBSWAP(SDValue Op, const SDLoc &dl);
186   SDValue ExpandPARITY(SDValue Op, const SDLoc &dl);
187 
188   SDValue ExpandExtractFromVectorThroughStack(SDValue Op);
189   SDValue ExpandInsertToVectorThroughStack(SDValue Op);
190   SDValue ExpandVectorBuildThroughStack(SDNode* Node);
191 
192   SDValue ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP);
193   SDValue ExpandConstant(ConstantSDNode *CP);
194 
195   // if ExpandNode returns false, LegalizeOp falls back to ConvertNodeToLibcall
196   bool ExpandNode(SDNode *Node);
197   void ConvertNodeToLibcall(SDNode *Node);
198   void PromoteNode(SDNode *Node);
199 
200 public:
201   // Node replacement helpers
202 
203   void ReplacedNode(SDNode *N) {
204     LegalizedNodes.erase(N);
205     if (UpdatedNodes)
206       UpdatedNodes->insert(N);
207   }
208 
209   void ReplaceNode(SDNode *Old, SDNode *New) {
210     LLVM_DEBUG(dbgs() << " ... replacing: "; Old->dump(&DAG);
211                dbgs() << "     with:      "; New->dump(&DAG));
212 
213     assert(Old->getNumValues() == New->getNumValues() &&
214            "Replacing one node with another that produces a different number "
215            "of values!");
216     DAG.ReplaceAllUsesWith(Old, New);
217     if (UpdatedNodes)
218       UpdatedNodes->insert(New);
219     ReplacedNode(Old);
220   }
221 
222   void ReplaceNode(SDValue Old, SDValue New) {
223     LLVM_DEBUG(dbgs() << " ... replacing: "; Old->dump(&DAG);
224                dbgs() << "     with:      "; New->dump(&DAG));
225 
226     DAG.ReplaceAllUsesWith(Old, New);
227     if (UpdatedNodes)
228       UpdatedNodes->insert(New.getNode());
229     ReplacedNode(Old.getNode());
230   }
231 
232   void ReplaceNode(SDNode *Old, const SDValue *New) {
233     LLVM_DEBUG(dbgs() << " ... replacing: "; Old->dump(&DAG));
234 
235     DAG.ReplaceAllUsesWith(Old, New);
236     for (unsigned i = 0, e = Old->getNumValues(); i != e; ++i) {
237       LLVM_DEBUG(dbgs() << (i == 0 ? "     with:      " : "      and:      ");
238                  New[i]->dump(&DAG));
239       if (UpdatedNodes)
240         UpdatedNodes->insert(New[i].getNode());
241     }
242     ReplacedNode(Old);
243   }
244 
245   void ReplaceNodeWithValue(SDValue Old, SDValue New) {
246     LLVM_DEBUG(dbgs() << " ... replacing: "; Old->dump(&DAG);
247                dbgs() << "     with:      "; New->dump(&DAG));
248 
249     DAG.ReplaceAllUsesOfValueWith(Old, New);
250     if (UpdatedNodes)
251       UpdatedNodes->insert(New.getNode());
252     ReplacedNode(Old.getNode());
253   }
254 };
255 
256 } // end anonymous namespace
257 
258 /// Return a vector shuffle operation which
259 /// performs the same shuffle in terms of order or result bytes, but on a type
260 /// whose vector element type is narrower than the original shuffle type.
261 /// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
262 SDValue SelectionDAGLegalize::ShuffleWithNarrowerEltType(
263     EVT NVT, EVT VT, const SDLoc &dl, SDValue N1, SDValue N2,
264     ArrayRef<int> Mask) const {
265   unsigned NumMaskElts = VT.getVectorNumElements();
266   unsigned NumDestElts = NVT.getVectorNumElements();
267   unsigned NumEltsGrowth = NumDestElts / NumMaskElts;
268 
269   assert(NumEltsGrowth && "Cannot promote to vector type with fewer elts!");
270 
271   if (NumEltsGrowth == 1)
272     return DAG.getVectorShuffle(NVT, dl, N1, N2, Mask);
273 
274   SmallVector<int, 8> NewMask;
275   for (unsigned i = 0; i != NumMaskElts; ++i) {
276     int Idx = Mask[i];
277     for (unsigned j = 0; j != NumEltsGrowth; ++j) {
278       if (Idx < 0)
279         NewMask.push_back(-1);
280       else
281         NewMask.push_back(Idx * NumEltsGrowth + j);
282     }
283   }
284   assert(NewMask.size() == NumDestElts && "Non-integer NumEltsGrowth?");
285   assert(TLI.isShuffleMaskLegal(NewMask, NVT) && "Shuffle not legal?");
286   return DAG.getVectorShuffle(NVT, dl, N1, N2, NewMask);
287 }
288 
289 /// Expands the ConstantFP node to an integer constant or
290 /// a load from the constant pool.
291 SDValue
292 SelectionDAGLegalize::ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP) {
293   bool Extend = false;
294   SDLoc dl(CFP);
295 
296   // If a FP immediate is precise when represented as a float and if the
297   // target can do an extending load from float to double, we put it into
298   // the constant pool as a float, even if it's is statically typed as a
299   // double.  This shrinks FP constants and canonicalizes them for targets where
300   // an FP extending load is the same cost as a normal load (such as on the x87
301   // fp stack or PPC FP unit).
302   EVT VT = CFP->getValueType(0);
303   ConstantFP *LLVMC = const_cast<ConstantFP*>(CFP->getConstantFPValue());
304   if (!UseCP) {
305     assert((VT == MVT::f64 || VT == MVT::f32) && "Invalid type expansion");
306     return DAG.getConstant(LLVMC->getValueAPF().bitcastToAPInt(), dl,
307                            (VT == MVT::f64) ? MVT::i64 : MVT::i32);
308   }
309 
310   APFloat APF = CFP->getValueAPF();
311   EVT OrigVT = VT;
312   EVT SVT = VT;
313 
314   // We don't want to shrink SNaNs. Converting the SNaN back to its real type
315   // can cause it to be changed into a QNaN on some platforms (e.g. on SystemZ).
316   if (!APF.isSignaling()) {
317     while (SVT != MVT::f32 && SVT != MVT::f16) {
318       SVT = (MVT::SimpleValueType)(SVT.getSimpleVT().SimpleTy - 1);
319       if (ConstantFPSDNode::isValueValidForType(SVT, APF) &&
320           // Only do this if the target has a native EXTLOAD instruction from
321           // smaller type.
322           TLI.isLoadExtLegal(ISD::EXTLOAD, OrigVT, SVT) &&
323           TLI.ShouldShrinkFPConstant(OrigVT)) {
324         Type *SType = SVT.getTypeForEVT(*DAG.getContext());
325         LLVMC = cast<ConstantFP>(ConstantExpr::getFPTrunc(LLVMC, SType));
326         VT = SVT;
327         Extend = true;
328       }
329     }
330   }
331 
332   SDValue CPIdx =
333       DAG.getConstantPool(LLVMC, TLI.getPointerTy(DAG.getDataLayout()));
334   Align Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlign();
335   if (Extend) {
336     SDValue Result = DAG.getExtLoad(
337         ISD::EXTLOAD, dl, OrigVT, DAG.getEntryNode(), CPIdx,
338         MachinePointerInfo::getConstantPool(DAG.getMachineFunction()), VT,
339         Alignment);
340     return Result;
341   }
342   SDValue Result = DAG.getLoad(
343       OrigVT, dl, DAG.getEntryNode(), CPIdx,
344       MachinePointerInfo::getConstantPool(DAG.getMachineFunction()), Alignment);
345   return Result;
346 }
347 
348 /// Expands the Constant node to a load from the constant pool.
349 SDValue SelectionDAGLegalize::ExpandConstant(ConstantSDNode *CP) {
350   SDLoc dl(CP);
351   EVT VT = CP->getValueType(0);
352   SDValue CPIdx = DAG.getConstantPool(CP->getConstantIntValue(),
353                                       TLI.getPointerTy(DAG.getDataLayout()));
354   Align Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlign();
355   SDValue Result = DAG.getLoad(
356       VT, dl, DAG.getEntryNode(), CPIdx,
357       MachinePointerInfo::getConstantPool(DAG.getMachineFunction()), Alignment);
358   return Result;
359 }
360 
361 /// Some target cannot handle a variable insertion index for the
362 /// INSERT_VECTOR_ELT instruction.  In this case, it
363 /// is necessary to spill the vector being inserted into to memory, perform
364 /// the insert there, and then read the result back.
365 SDValue SelectionDAGLegalize::PerformInsertVectorEltInMemory(SDValue Vec,
366                                                              SDValue Val,
367                                                              SDValue Idx,
368                                                              const SDLoc &dl) {
369   SDValue Tmp1 = Vec;
370   SDValue Tmp2 = Val;
371   SDValue Tmp3 = Idx;
372 
373   // If the target doesn't support this, we have to spill the input vector
374   // to a temporary stack slot, update the element, then reload it.  This is
375   // badness.  We could also load the value into a vector register (either
376   // with a "move to register" or "extload into register" instruction, then
377   // permute it into place, if the idx is a constant and if the idx is
378   // supported by the target.
379   EVT VT    = Tmp1.getValueType();
380   EVT EltVT = VT.getVectorElementType();
381   SDValue StackPtr = DAG.CreateStackTemporary(VT);
382 
383   int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
384 
385   // Store the vector.
386   SDValue Ch = DAG.getStore(
387       DAG.getEntryNode(), dl, Tmp1, StackPtr,
388       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI));
389 
390   SDValue StackPtr2 = TLI.getVectorElementPointer(DAG, StackPtr, VT, Tmp3);
391 
392   // Store the scalar value.
393   Ch = DAG.getTruncStore(
394       Ch, dl, Tmp2, StackPtr2,
395       MachinePointerInfo::getUnknownStack(DAG.getMachineFunction()), EltVT);
396   // Load the updated vector.
397   return DAG.getLoad(VT, dl, Ch, StackPtr, MachinePointerInfo::getFixedStack(
398                                                DAG.getMachineFunction(), SPFI));
399 }
400 
401 SDValue SelectionDAGLegalize::ExpandINSERT_VECTOR_ELT(SDValue Vec, SDValue Val,
402                                                       SDValue Idx,
403                                                       const SDLoc &dl) {
404   if (ConstantSDNode *InsertPos = dyn_cast<ConstantSDNode>(Idx)) {
405     // SCALAR_TO_VECTOR requires that the type of the value being inserted
406     // match the element type of the vector being created, except for
407     // integers in which case the inserted value can be over width.
408     EVT EltVT = Vec.getValueType().getVectorElementType();
409     if (Val.getValueType() == EltVT ||
410         (EltVT.isInteger() && Val.getValueType().bitsGE(EltVT))) {
411       SDValue ScVec = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl,
412                                   Vec.getValueType(), Val);
413 
414       unsigned NumElts = Vec.getValueType().getVectorNumElements();
415       // We generate a shuffle of InVec and ScVec, so the shuffle mask
416       // should be 0,1,2,3,4,5... with the appropriate element replaced with
417       // elt 0 of the RHS.
418       SmallVector<int, 8> ShufOps;
419       for (unsigned i = 0; i != NumElts; ++i)
420         ShufOps.push_back(i != InsertPos->getZExtValue() ? i : NumElts);
421 
422       return DAG.getVectorShuffle(Vec.getValueType(), dl, Vec, ScVec, ShufOps);
423     }
424   }
425   return PerformInsertVectorEltInMemory(Vec, Val, Idx, dl);
426 }
427 
428 SDValue SelectionDAGLegalize::OptimizeFloatStore(StoreSDNode* ST) {
429   if (!ISD::isNormalStore(ST))
430     return SDValue();
431 
432   LLVM_DEBUG(dbgs() << "Optimizing float store operations\n");
433   // Turn 'store float 1.0, Ptr' -> 'store int 0x12345678, Ptr'
434   // FIXME: We shouldn't do this for TargetConstantFP's.
435   // FIXME: move this to the DAG Combiner!  Note that we can't regress due
436   // to phase ordering between legalized code and the dag combiner.  This
437   // probably means that we need to integrate dag combiner and legalizer
438   // together.
439   // We generally can't do this one for long doubles.
440   SDValue Chain = ST->getChain();
441   SDValue Ptr = ST->getBasePtr();
442   MachineMemOperand::Flags MMOFlags = ST->getMemOperand()->getFlags();
443   AAMDNodes AAInfo = ST->getAAInfo();
444   SDLoc dl(ST);
445   if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(ST->getValue())) {
446     if (CFP->getValueType(0) == MVT::f32 &&
447         TLI.isTypeLegal(MVT::i32)) {
448       SDValue Con = DAG.getConstant(CFP->getValueAPF().
449                                       bitcastToAPInt().zextOrTrunc(32),
450                                     SDLoc(CFP), MVT::i32);
451       return DAG.getStore(Chain, dl, Con, Ptr, ST->getPointerInfo(),
452                           ST->getOriginalAlign(), MMOFlags, AAInfo);
453     }
454 
455     if (CFP->getValueType(0) == MVT::f64) {
456       // If this target supports 64-bit registers, do a single 64-bit store.
457       if (TLI.isTypeLegal(MVT::i64)) {
458         SDValue Con = DAG.getConstant(CFP->getValueAPF().bitcastToAPInt().
459                                       zextOrTrunc(64), SDLoc(CFP), MVT::i64);
460         return DAG.getStore(Chain, dl, Con, Ptr, ST->getPointerInfo(),
461                             ST->getOriginalAlign(), MMOFlags, AAInfo);
462       }
463 
464       if (TLI.isTypeLegal(MVT::i32) && !ST->isVolatile()) {
465         // Otherwise, if the target supports 32-bit registers, use 2 32-bit
466         // stores.  If the target supports neither 32- nor 64-bits, this
467         // xform is certainly not worth it.
468         const APInt &IntVal = CFP->getValueAPF().bitcastToAPInt();
469         SDValue Lo = DAG.getConstant(IntVal.trunc(32), dl, MVT::i32);
470         SDValue Hi = DAG.getConstant(IntVal.lshr(32).trunc(32), dl, MVT::i32);
471         if (DAG.getDataLayout().isBigEndian())
472           std::swap(Lo, Hi);
473 
474         Lo = DAG.getStore(Chain, dl, Lo, Ptr, ST->getPointerInfo(),
475                           ST->getOriginalAlign(), MMOFlags, AAInfo);
476         Ptr = DAG.getMemBasePlusOffset(Ptr, TypeSize::Fixed(4), dl);
477         Hi = DAG.getStore(Chain, dl, Hi, Ptr,
478                           ST->getPointerInfo().getWithOffset(4),
479                           ST->getOriginalAlign(), MMOFlags, AAInfo);
480 
481         return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
482       }
483     }
484   }
485   return SDValue(nullptr, 0);
486 }
487 
488 void SelectionDAGLegalize::LegalizeStoreOps(SDNode *Node) {
489   StoreSDNode *ST = cast<StoreSDNode>(Node);
490   SDValue Chain = ST->getChain();
491   SDValue Ptr = ST->getBasePtr();
492   SDLoc dl(Node);
493 
494   MachineMemOperand::Flags MMOFlags = ST->getMemOperand()->getFlags();
495   AAMDNodes AAInfo = ST->getAAInfo();
496 
497   if (!ST->isTruncatingStore()) {
498     LLVM_DEBUG(dbgs() << "Legalizing store operation\n");
499     if (SDNode *OptStore = OptimizeFloatStore(ST).getNode()) {
500       ReplaceNode(ST, OptStore);
501       return;
502     }
503 
504     SDValue Value = ST->getValue();
505     MVT VT = Value.getSimpleValueType();
506     switch (TLI.getOperationAction(ISD::STORE, VT)) {
507     default: llvm_unreachable("This action is not supported yet!");
508     case TargetLowering::Legal: {
509       // If this is an unaligned store and the target doesn't support it,
510       // expand it.
511       EVT MemVT = ST->getMemoryVT();
512       const DataLayout &DL = DAG.getDataLayout();
513       if (!TLI.allowsMemoryAccessForAlignment(*DAG.getContext(), DL, MemVT,
514                                               *ST->getMemOperand())) {
515         LLVM_DEBUG(dbgs() << "Expanding unsupported unaligned store\n");
516         SDValue Result = TLI.expandUnalignedStore(ST, DAG);
517         ReplaceNode(SDValue(ST, 0), Result);
518       } else
519         LLVM_DEBUG(dbgs() << "Legal store\n");
520       break;
521     }
522     case TargetLowering::Custom: {
523       LLVM_DEBUG(dbgs() << "Trying custom lowering\n");
524       SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
525       if (Res && Res != SDValue(Node, 0))
526         ReplaceNode(SDValue(Node, 0), Res);
527       return;
528     }
529     case TargetLowering::Promote: {
530       MVT NVT = TLI.getTypeToPromoteTo(ISD::STORE, VT);
531       assert(NVT.getSizeInBits() == VT.getSizeInBits() &&
532              "Can only promote stores to same size type");
533       Value = DAG.getNode(ISD::BITCAST, dl, NVT, Value);
534       SDValue Result = DAG.getStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
535                                     ST->getOriginalAlign(), MMOFlags, AAInfo);
536       ReplaceNode(SDValue(Node, 0), Result);
537       break;
538     }
539     }
540     return;
541   }
542 
543   LLVM_DEBUG(dbgs() << "Legalizing truncating store operations\n");
544   SDValue Value = ST->getValue();
545   EVT StVT = ST->getMemoryVT();
546   TypeSize StWidth = StVT.getSizeInBits();
547   TypeSize StSize = StVT.getStoreSizeInBits();
548   auto &DL = DAG.getDataLayout();
549 
550   if (StWidth != StSize) {
551     // Promote to a byte-sized store with upper bits zero if not
552     // storing an integral number of bytes.  For example, promote
553     // TRUNCSTORE:i1 X -> TRUNCSTORE:i8 (and X, 1)
554     EVT NVT = EVT::getIntegerVT(*DAG.getContext(), StSize.getFixedSize());
555     Value = DAG.getZeroExtendInReg(Value, dl, StVT);
556     SDValue Result =
557         DAG.getTruncStore(Chain, dl, Value, Ptr, ST->getPointerInfo(), NVT,
558                           ST->getOriginalAlign(), MMOFlags, AAInfo);
559     ReplaceNode(SDValue(Node, 0), Result);
560   } else if (!StVT.isVector() && !isPowerOf2_64(StWidth.getFixedSize())) {
561     // If not storing a power-of-2 number of bits, expand as two stores.
562     assert(!StVT.isVector() && "Unsupported truncstore!");
563     unsigned StWidthBits = StWidth.getFixedSize();
564     unsigned LogStWidth = Log2_32(StWidthBits);
565     assert(LogStWidth < 32);
566     unsigned RoundWidth = 1 << LogStWidth;
567     assert(RoundWidth < StWidthBits);
568     unsigned ExtraWidth = StWidthBits - RoundWidth;
569     assert(ExtraWidth < RoundWidth);
570     assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
571            "Store size not an integral number of bytes!");
572     EVT RoundVT = EVT::getIntegerVT(*DAG.getContext(), RoundWidth);
573     EVT ExtraVT = EVT::getIntegerVT(*DAG.getContext(), ExtraWidth);
574     SDValue Lo, Hi;
575     unsigned IncrementSize;
576 
577     if (DL.isLittleEndian()) {
578       // TRUNCSTORE:i24 X -> TRUNCSTORE:i16 X, TRUNCSTORE@+2:i8 (srl X, 16)
579       // Store the bottom RoundWidth bits.
580       Lo = DAG.getTruncStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
581                              RoundVT, ST->getOriginalAlign(), MMOFlags, AAInfo);
582 
583       // Store the remaining ExtraWidth bits.
584       IncrementSize = RoundWidth / 8;
585       Ptr = DAG.getMemBasePlusOffset(Ptr, TypeSize::Fixed(IncrementSize), dl);
586       Hi = DAG.getNode(
587           ISD::SRL, dl, Value.getValueType(), Value,
588           DAG.getConstant(RoundWidth, dl,
589                           TLI.getShiftAmountTy(Value.getValueType(), DL)));
590       Hi = DAG.getTruncStore(Chain, dl, Hi, Ptr,
591                              ST->getPointerInfo().getWithOffset(IncrementSize),
592                              ExtraVT, ST->getOriginalAlign(), MMOFlags, AAInfo);
593     } else {
594       // Big endian - avoid unaligned stores.
595       // TRUNCSTORE:i24 X -> TRUNCSTORE:i16 (srl X, 8), TRUNCSTORE@+2:i8 X
596       // Store the top RoundWidth bits.
597       Hi = DAG.getNode(
598           ISD::SRL, dl, Value.getValueType(), Value,
599           DAG.getConstant(ExtraWidth, dl,
600                           TLI.getShiftAmountTy(Value.getValueType(), DL)));
601       Hi = DAG.getTruncStore(Chain, dl, Hi, Ptr, ST->getPointerInfo(), RoundVT,
602                              ST->getOriginalAlign(), MMOFlags, AAInfo);
603 
604       // Store the remaining ExtraWidth bits.
605       IncrementSize = RoundWidth / 8;
606       Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
607                         DAG.getConstant(IncrementSize, dl,
608                                         Ptr.getValueType()));
609       Lo = DAG.getTruncStore(Chain, dl, Value, Ptr,
610                              ST->getPointerInfo().getWithOffset(IncrementSize),
611                              ExtraVT, ST->getOriginalAlign(), MMOFlags, AAInfo);
612     }
613 
614     // The order of the stores doesn't matter.
615     SDValue Result = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
616     ReplaceNode(SDValue(Node, 0), Result);
617   } else {
618     switch (TLI.getTruncStoreAction(ST->getValue().getValueType(), StVT)) {
619     default: llvm_unreachable("This action is not supported yet!");
620     case TargetLowering::Legal: {
621       EVT MemVT = ST->getMemoryVT();
622       // If this is an unaligned store and the target doesn't support it,
623       // expand it.
624       if (!TLI.allowsMemoryAccessForAlignment(*DAG.getContext(), DL, MemVT,
625                                               *ST->getMemOperand())) {
626         SDValue Result = TLI.expandUnalignedStore(ST, DAG);
627         ReplaceNode(SDValue(ST, 0), Result);
628       }
629       break;
630     }
631     case TargetLowering::Custom: {
632       SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG);
633       if (Res && Res != SDValue(Node, 0))
634         ReplaceNode(SDValue(Node, 0), Res);
635       return;
636     }
637     case TargetLowering::Expand:
638       assert(!StVT.isVector() &&
639              "Vector Stores are handled in LegalizeVectorOps");
640 
641       SDValue Result;
642 
643       // TRUNCSTORE:i16 i32 -> STORE i16
644       if (TLI.isTypeLegal(StVT)) {
645         Value = DAG.getNode(ISD::TRUNCATE, dl, StVT, Value);
646         Result = DAG.getStore(Chain, dl, Value, Ptr, ST->getPointerInfo(),
647                               ST->getOriginalAlign(), MMOFlags, AAInfo);
648       } else {
649         // The in-memory type isn't legal. Truncate to the type it would promote
650         // to, and then do a truncstore.
651         Value = DAG.getNode(ISD::TRUNCATE, dl,
652                             TLI.getTypeToTransformTo(*DAG.getContext(), StVT),
653                             Value);
654         Result =
655             DAG.getTruncStore(Chain, dl, Value, Ptr, ST->getPointerInfo(), StVT,
656                               ST->getOriginalAlign(), MMOFlags, AAInfo);
657       }
658 
659       ReplaceNode(SDValue(Node, 0), Result);
660       break;
661     }
662   }
663 }
664 
665 void SelectionDAGLegalize::LegalizeLoadOps(SDNode *Node) {
666   LoadSDNode *LD = cast<LoadSDNode>(Node);
667   SDValue Chain = LD->getChain();  // The chain.
668   SDValue Ptr = LD->getBasePtr();  // The base pointer.
669   SDValue Value;                   // The value returned by the load op.
670   SDLoc dl(Node);
671 
672   ISD::LoadExtType ExtType = LD->getExtensionType();
673   if (ExtType == ISD::NON_EXTLOAD) {
674     LLVM_DEBUG(dbgs() << "Legalizing non-extending load operation\n");
675     MVT VT = Node->getSimpleValueType(0);
676     SDValue RVal = SDValue(Node, 0);
677     SDValue RChain = SDValue(Node, 1);
678 
679     switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
680     default: llvm_unreachable("This action is not supported yet!");
681     case TargetLowering::Legal: {
682       EVT MemVT = LD->getMemoryVT();
683       const DataLayout &DL = DAG.getDataLayout();
684       // If this is an unaligned load and the target doesn't support it,
685       // expand it.
686       if (!TLI.allowsMemoryAccessForAlignment(*DAG.getContext(), DL, MemVT,
687                                               *LD->getMemOperand())) {
688         std::tie(RVal, RChain) = TLI.expandUnalignedLoad(LD, DAG);
689       }
690       break;
691     }
692     case TargetLowering::Custom:
693       if (SDValue Res = TLI.LowerOperation(RVal, DAG)) {
694         RVal = Res;
695         RChain = Res.getValue(1);
696       }
697       break;
698 
699     case TargetLowering::Promote: {
700       MVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), VT);
701       assert(NVT.getSizeInBits() == VT.getSizeInBits() &&
702              "Can only promote loads to same size type");
703 
704       SDValue Res = DAG.getLoad(NVT, dl, Chain, Ptr, LD->getMemOperand());
705       RVal = DAG.getNode(ISD::BITCAST, dl, VT, Res);
706       RChain = Res.getValue(1);
707       break;
708     }
709     }
710     if (RChain.getNode() != Node) {
711       assert(RVal.getNode() != Node && "Load must be completely replaced");
712       DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), RVal);
713       DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), RChain);
714       if (UpdatedNodes) {
715         UpdatedNodes->insert(RVal.getNode());
716         UpdatedNodes->insert(RChain.getNode());
717       }
718       ReplacedNode(Node);
719     }
720     return;
721   }
722 
723   LLVM_DEBUG(dbgs() << "Legalizing extending load operation\n");
724   EVT SrcVT = LD->getMemoryVT();
725   TypeSize SrcWidth = SrcVT.getSizeInBits();
726   MachineMemOperand::Flags MMOFlags = LD->getMemOperand()->getFlags();
727   AAMDNodes AAInfo = LD->getAAInfo();
728 
729   if (SrcWidth != SrcVT.getStoreSizeInBits() &&
730       // Some targets pretend to have an i1 loading operation, and actually
731       // load an i8.  This trick is correct for ZEXTLOAD because the top 7
732       // bits are guaranteed to be zero; it helps the optimizers understand
733       // that these bits are zero.  It is also useful for EXTLOAD, since it
734       // tells the optimizers that those bits are undefined.  It would be
735       // nice to have an effective generic way of getting these benefits...
736       // Until such a way is found, don't insist on promoting i1 here.
737       (SrcVT != MVT::i1 ||
738        TLI.getLoadExtAction(ExtType, Node->getValueType(0), MVT::i1) ==
739          TargetLowering::Promote)) {
740     // Promote to a byte-sized load if not loading an integral number of
741     // bytes.  For example, promote EXTLOAD:i20 -> EXTLOAD:i24.
742     unsigned NewWidth = SrcVT.getStoreSizeInBits();
743     EVT NVT = EVT::getIntegerVT(*DAG.getContext(), NewWidth);
744     SDValue Ch;
745 
746     // The extra bits are guaranteed to be zero, since we stored them that
747     // way.  A zext load from NVT thus automatically gives zext from SrcVT.
748 
749     ISD::LoadExtType NewExtType =
750       ExtType == ISD::ZEXTLOAD ? ISD::ZEXTLOAD : ISD::EXTLOAD;
751 
752     SDValue Result = DAG.getExtLoad(NewExtType, dl, Node->getValueType(0),
753                                     Chain, Ptr, LD->getPointerInfo(), NVT,
754                                     LD->getOriginalAlign(), MMOFlags, AAInfo);
755 
756     Ch = Result.getValue(1); // The chain.
757 
758     if (ExtType == ISD::SEXTLOAD)
759       // Having the top bits zero doesn't help when sign extending.
760       Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
761                            Result.getValueType(),
762                            Result, DAG.getValueType(SrcVT));
763     else if (ExtType == ISD::ZEXTLOAD || NVT == Result.getValueType())
764       // All the top bits are guaranteed to be zero - inform the optimizers.
765       Result = DAG.getNode(ISD::AssertZext, dl,
766                            Result.getValueType(), Result,
767                            DAG.getValueType(SrcVT));
768 
769     Value = Result;
770     Chain = Ch;
771   } else if (!isPowerOf2_64(SrcWidth.getKnownMinSize())) {
772     // If not loading a power-of-2 number of bits, expand as two loads.
773     assert(!SrcVT.isVector() && "Unsupported extload!");
774     unsigned SrcWidthBits = SrcWidth.getFixedSize();
775     unsigned LogSrcWidth = Log2_32(SrcWidthBits);
776     assert(LogSrcWidth < 32);
777     unsigned RoundWidth = 1 << LogSrcWidth;
778     assert(RoundWidth < SrcWidthBits);
779     unsigned ExtraWidth = SrcWidthBits - RoundWidth;
780     assert(ExtraWidth < RoundWidth);
781     assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
782            "Load size not an integral number of bytes!");
783     EVT RoundVT = EVT::getIntegerVT(*DAG.getContext(), RoundWidth);
784     EVT ExtraVT = EVT::getIntegerVT(*DAG.getContext(), ExtraWidth);
785     SDValue Lo, Hi, Ch;
786     unsigned IncrementSize;
787     auto &DL = DAG.getDataLayout();
788 
789     if (DL.isLittleEndian()) {
790       // EXTLOAD:i24 -> ZEXTLOAD:i16 | (shl EXTLOAD@+2:i8, 16)
791       // Load the bottom RoundWidth bits.
792       Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, Node->getValueType(0), Chain, Ptr,
793                           LD->getPointerInfo(), RoundVT, LD->getOriginalAlign(),
794                           MMOFlags, AAInfo);
795 
796       // Load the remaining ExtraWidth bits.
797       IncrementSize = RoundWidth / 8;
798       Ptr = DAG.getMemBasePlusOffset(Ptr, TypeSize::Fixed(IncrementSize), dl);
799       Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Chain, Ptr,
800                           LD->getPointerInfo().getWithOffset(IncrementSize),
801                           ExtraVT, LD->getOriginalAlign(), MMOFlags, AAInfo);
802 
803       // Build a factor node to remember that this load is independent of
804       // the other one.
805       Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
806                        Hi.getValue(1));
807 
808       // Move the top bits to the right place.
809       Hi = DAG.getNode(
810           ISD::SHL, dl, Hi.getValueType(), Hi,
811           DAG.getConstant(RoundWidth, dl,
812                           TLI.getShiftAmountTy(Hi.getValueType(), DL)));
813 
814       // Join the hi and lo parts.
815       Value = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
816     } else {
817       // Big endian - avoid unaligned loads.
818       // EXTLOAD:i24 -> (shl EXTLOAD:i16, 8) | ZEXTLOAD@+2:i8
819       // Load the top RoundWidth bits.
820       Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Chain, Ptr,
821                           LD->getPointerInfo(), RoundVT, LD->getOriginalAlign(),
822                           MMOFlags, AAInfo);
823 
824       // Load the remaining ExtraWidth bits.
825       IncrementSize = RoundWidth / 8;
826       Ptr = DAG.getMemBasePlusOffset(Ptr, TypeSize::Fixed(IncrementSize), dl);
827       Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, Node->getValueType(0), Chain, Ptr,
828                           LD->getPointerInfo().getWithOffset(IncrementSize),
829                           ExtraVT, LD->getOriginalAlign(), MMOFlags, AAInfo);
830 
831       // Build a factor node to remember that this load is independent of
832       // the other one.
833       Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
834                        Hi.getValue(1));
835 
836       // Move the top bits to the right place.
837       Hi = DAG.getNode(
838           ISD::SHL, dl, Hi.getValueType(), Hi,
839           DAG.getConstant(ExtraWidth, dl,
840                           TLI.getShiftAmountTy(Hi.getValueType(), DL)));
841 
842       // Join the hi and lo parts.
843       Value = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
844     }
845 
846     Chain = Ch;
847   } else {
848     bool isCustom = false;
849     switch (TLI.getLoadExtAction(ExtType, Node->getValueType(0),
850                                  SrcVT.getSimpleVT())) {
851     default: llvm_unreachable("This action is not supported yet!");
852     case TargetLowering::Custom:
853       isCustom = true;
854       LLVM_FALLTHROUGH;
855     case TargetLowering::Legal:
856       Value = SDValue(Node, 0);
857       Chain = SDValue(Node, 1);
858 
859       if (isCustom) {
860         if (SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG)) {
861           Value = Res;
862           Chain = Res.getValue(1);
863         }
864       } else {
865         // If this is an unaligned load and the target doesn't support it,
866         // expand it.
867         EVT MemVT = LD->getMemoryVT();
868         const DataLayout &DL = DAG.getDataLayout();
869         if (!TLI.allowsMemoryAccess(*DAG.getContext(), DL, MemVT,
870                                     *LD->getMemOperand())) {
871           std::tie(Value, Chain) = TLI.expandUnalignedLoad(LD, DAG);
872         }
873       }
874       break;
875 
876     case TargetLowering::Expand: {
877       EVT DestVT = Node->getValueType(0);
878       if (!TLI.isLoadExtLegal(ISD::EXTLOAD, DestVT, SrcVT)) {
879         // If the source type is not legal, see if there is a legal extload to
880         // an intermediate type that we can then extend further.
881         EVT LoadVT = TLI.getRegisterType(SrcVT.getSimpleVT());
882         if (TLI.isTypeLegal(SrcVT) || // Same as SrcVT == LoadVT?
883             TLI.isLoadExtLegal(ExtType, LoadVT, SrcVT)) {
884           // If we are loading a legal type, this is a non-extload followed by a
885           // full extend.
886           ISD::LoadExtType MidExtType =
887               (LoadVT == SrcVT) ? ISD::NON_EXTLOAD : ExtType;
888 
889           SDValue Load = DAG.getExtLoad(MidExtType, dl, LoadVT, Chain, Ptr,
890                                         SrcVT, LD->getMemOperand());
891           unsigned ExtendOp =
892               ISD::getExtForLoadExtType(SrcVT.isFloatingPoint(), ExtType);
893           Value = DAG.getNode(ExtendOp, dl, Node->getValueType(0), Load);
894           Chain = Load.getValue(1);
895           break;
896         }
897 
898         // Handle the special case of fp16 extloads. EXTLOAD doesn't have the
899         // normal undefined upper bits behavior to allow using an in-reg extend
900         // with the illegal FP type, so load as an integer and do the
901         // from-integer conversion.
902         if (SrcVT.getScalarType() == MVT::f16) {
903           EVT ISrcVT = SrcVT.changeTypeToInteger();
904           EVT IDestVT = DestVT.changeTypeToInteger();
905           EVT ILoadVT = TLI.getRegisterType(IDestVT.getSimpleVT());
906 
907           SDValue Result = DAG.getExtLoad(ISD::ZEXTLOAD, dl, ILoadVT, Chain,
908                                           Ptr, ISrcVT, LD->getMemOperand());
909           Value = DAG.getNode(ISD::FP16_TO_FP, dl, DestVT, Result);
910           Chain = Result.getValue(1);
911           break;
912         }
913       }
914 
915       assert(!SrcVT.isVector() &&
916              "Vector Loads are handled in LegalizeVectorOps");
917 
918       // FIXME: This does not work for vectors on most targets.  Sign-
919       // and zero-extend operations are currently folded into extending
920       // loads, whether they are legal or not, and then we end up here
921       // without any support for legalizing them.
922       assert(ExtType != ISD::EXTLOAD &&
923              "EXTLOAD should always be supported!");
924       // Turn the unsupported load into an EXTLOAD followed by an
925       // explicit zero/sign extend inreg.
926       SDValue Result = DAG.getExtLoad(ISD::EXTLOAD, dl,
927                                       Node->getValueType(0),
928                                       Chain, Ptr, SrcVT,
929                                       LD->getMemOperand());
930       SDValue ValRes;
931       if (ExtType == ISD::SEXTLOAD)
932         ValRes = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
933                              Result.getValueType(),
934                              Result, DAG.getValueType(SrcVT));
935       else
936         ValRes = DAG.getZeroExtendInReg(Result, dl, SrcVT);
937       Value = ValRes;
938       Chain = Result.getValue(1);
939       break;
940     }
941     }
942   }
943 
944   // Since loads produce two values, make sure to remember that we legalized
945   // both of them.
946   if (Chain.getNode() != Node) {
947     assert(Value.getNode() != Node && "Load must be completely replaced");
948     DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), Value);
949     DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), Chain);
950     if (UpdatedNodes) {
951       UpdatedNodes->insert(Value.getNode());
952       UpdatedNodes->insert(Chain.getNode());
953     }
954     ReplacedNode(Node);
955   }
956 }
957 
958 /// Return a legal replacement for the given operation, with all legal operands.
959 void SelectionDAGLegalize::LegalizeOp(SDNode *Node) {
960   LLVM_DEBUG(dbgs() << "\nLegalizing: "; Node->dump(&DAG));
961 
962   // Allow illegal target nodes and illegal registers.
963   if (Node->getOpcode() == ISD::TargetConstant ||
964       Node->getOpcode() == ISD::Register)
965     return;
966 
967 #ifndef NDEBUG
968   for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
969     assert(TLI.getTypeAction(*DAG.getContext(), Node->getValueType(i)) ==
970              TargetLowering::TypeLegal &&
971            "Unexpected illegal type!");
972 
973   for (const SDValue &Op : Node->op_values())
974     assert((TLI.getTypeAction(*DAG.getContext(), Op.getValueType()) ==
975               TargetLowering::TypeLegal ||
976             Op.getOpcode() == ISD::TargetConstant ||
977             Op.getOpcode() == ISD::Register) &&
978             "Unexpected illegal type!");
979 #endif
980 
981   // Figure out the correct action; the way to query this varies by opcode
982   TargetLowering::LegalizeAction Action = TargetLowering::Legal;
983   bool SimpleFinishLegalizing = true;
984   switch (Node->getOpcode()) {
985   case ISD::INTRINSIC_W_CHAIN:
986   case ISD::INTRINSIC_WO_CHAIN:
987   case ISD::INTRINSIC_VOID:
988   case ISD::STACKSAVE:
989     Action = TLI.getOperationAction(Node->getOpcode(), MVT::Other);
990     break;
991   case ISD::GET_DYNAMIC_AREA_OFFSET:
992     Action = TLI.getOperationAction(Node->getOpcode(),
993                                     Node->getValueType(0));
994     break;
995   case ISD::VAARG:
996     Action = TLI.getOperationAction(Node->getOpcode(),
997                                     Node->getValueType(0));
998     if (Action != TargetLowering::Promote)
999       Action = TLI.getOperationAction(Node->getOpcode(), MVT::Other);
1000     break;
1001   case ISD::FP_TO_FP16:
1002   case ISD::SINT_TO_FP:
1003   case ISD::UINT_TO_FP:
1004   case ISD::EXTRACT_VECTOR_ELT:
1005   case ISD::LROUND:
1006   case ISD::LLROUND:
1007   case ISD::LRINT:
1008   case ISD::LLRINT:
1009     Action = TLI.getOperationAction(Node->getOpcode(),
1010                                     Node->getOperand(0).getValueType());
1011     break;
1012   case ISD::STRICT_FP_TO_FP16:
1013   case ISD::STRICT_SINT_TO_FP:
1014   case ISD::STRICT_UINT_TO_FP:
1015   case ISD::STRICT_LRINT:
1016   case ISD::STRICT_LLRINT:
1017   case ISD::STRICT_LROUND:
1018   case ISD::STRICT_LLROUND:
1019     // These pseudo-ops are the same as the other STRICT_ ops except
1020     // they are registered with setOperationAction() using the input type
1021     // instead of the output type.
1022     Action = TLI.getOperationAction(Node->getOpcode(),
1023                                     Node->getOperand(1).getValueType());
1024     break;
1025   case ISD::SIGN_EXTEND_INREG: {
1026     EVT InnerType = cast<VTSDNode>(Node->getOperand(1))->getVT();
1027     Action = TLI.getOperationAction(Node->getOpcode(), InnerType);
1028     break;
1029   }
1030   case ISD::ATOMIC_STORE:
1031     Action = TLI.getOperationAction(Node->getOpcode(),
1032                                     Node->getOperand(2).getValueType());
1033     break;
1034   case ISD::SELECT_CC:
1035   case ISD::STRICT_FSETCC:
1036   case ISD::STRICT_FSETCCS:
1037   case ISD::SETCC:
1038   case ISD::BR_CC: {
1039     unsigned CCOperand = Node->getOpcode() == ISD::SELECT_CC ? 4 :
1040                          Node->getOpcode() == ISD::STRICT_FSETCC ? 3 :
1041                          Node->getOpcode() == ISD::STRICT_FSETCCS ? 3 :
1042                          Node->getOpcode() == ISD::SETCC ? 2 : 1;
1043     unsigned CompareOperand = Node->getOpcode() == ISD::BR_CC ? 2 :
1044                               Node->getOpcode() == ISD::STRICT_FSETCC ? 1 :
1045                               Node->getOpcode() == ISD::STRICT_FSETCCS ? 1 : 0;
1046     MVT OpVT = Node->getOperand(CompareOperand).getSimpleValueType();
1047     ISD::CondCode CCCode =
1048         cast<CondCodeSDNode>(Node->getOperand(CCOperand))->get();
1049     Action = TLI.getCondCodeAction(CCCode, OpVT);
1050     if (Action == TargetLowering::Legal) {
1051       if (Node->getOpcode() == ISD::SELECT_CC)
1052         Action = TLI.getOperationAction(Node->getOpcode(),
1053                                         Node->getValueType(0));
1054       else
1055         Action = TLI.getOperationAction(Node->getOpcode(), OpVT);
1056     }
1057     break;
1058   }
1059   case ISD::LOAD:
1060   case ISD::STORE:
1061     // FIXME: Model these properly.  LOAD and STORE are complicated, and
1062     // STORE expects the unlegalized operand in some cases.
1063     SimpleFinishLegalizing = false;
1064     break;
1065   case ISD::CALLSEQ_START:
1066   case ISD::CALLSEQ_END:
1067     // FIXME: This shouldn't be necessary.  These nodes have special properties
1068     // dealing with the recursive nature of legalization.  Removing this
1069     // special case should be done as part of making LegalizeDAG non-recursive.
1070     SimpleFinishLegalizing = false;
1071     break;
1072   case ISD::EXTRACT_ELEMENT:
1073   case ISD::FLT_ROUNDS_:
1074   case ISD::MERGE_VALUES:
1075   case ISD::EH_RETURN:
1076   case ISD::FRAME_TO_ARGS_OFFSET:
1077   case ISD::EH_DWARF_CFA:
1078   case ISD::EH_SJLJ_SETJMP:
1079   case ISD::EH_SJLJ_LONGJMP:
1080   case ISD::EH_SJLJ_SETUP_DISPATCH:
1081     // These operations lie about being legal: when they claim to be legal,
1082     // they should actually be expanded.
1083     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1084     if (Action == TargetLowering::Legal)
1085       Action = TargetLowering::Expand;
1086     break;
1087   case ISD::INIT_TRAMPOLINE:
1088   case ISD::ADJUST_TRAMPOLINE:
1089   case ISD::FRAMEADDR:
1090   case ISD::RETURNADDR:
1091   case ISD::ADDROFRETURNADDR:
1092   case ISD::SPONENTRY:
1093     // These operations lie about being legal: when they claim to be legal,
1094     // they should actually be custom-lowered.
1095     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1096     if (Action == TargetLowering::Legal)
1097       Action = TargetLowering::Custom;
1098     break;
1099   case ISD::READCYCLECOUNTER:
1100     // READCYCLECOUNTER returns an i64, even if type legalization might have
1101     // expanded that to several smaller types.
1102     Action = TLI.getOperationAction(Node->getOpcode(), MVT::i64);
1103     break;
1104   case ISD::READ_REGISTER:
1105   case ISD::WRITE_REGISTER:
1106     // Named register is legal in the DAG, but blocked by register name
1107     // selection if not implemented by target (to chose the correct register)
1108     // They'll be converted to Copy(To/From)Reg.
1109     Action = TargetLowering::Legal;
1110     break;
1111   case ISD::UBSANTRAP:
1112     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1113     if (Action == TargetLowering::Expand) {
1114       // replace ISD::UBSANTRAP with ISD::TRAP
1115       SDValue NewVal;
1116       NewVal = DAG.getNode(ISD::TRAP, SDLoc(Node), Node->getVTList(),
1117                            Node->getOperand(0));
1118       ReplaceNode(Node, NewVal.getNode());
1119       LegalizeOp(NewVal.getNode());
1120       return;
1121     }
1122     break;
1123   case ISD::DEBUGTRAP:
1124     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1125     if (Action == TargetLowering::Expand) {
1126       // replace ISD::DEBUGTRAP with ISD::TRAP
1127       SDValue NewVal;
1128       NewVal = DAG.getNode(ISD::TRAP, SDLoc(Node), Node->getVTList(),
1129                            Node->getOperand(0));
1130       ReplaceNode(Node, NewVal.getNode());
1131       LegalizeOp(NewVal.getNode());
1132       return;
1133     }
1134     break;
1135   case ISD::SADDSAT:
1136   case ISD::UADDSAT:
1137   case ISD::SSUBSAT:
1138   case ISD::USUBSAT:
1139   case ISD::SSHLSAT:
1140   case ISD::USHLSAT:
1141   case ISD::FP_TO_SINT_SAT:
1142   case ISD::FP_TO_UINT_SAT:
1143     Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1144     break;
1145   case ISD::SMULFIX:
1146   case ISD::SMULFIXSAT:
1147   case ISD::UMULFIX:
1148   case ISD::UMULFIXSAT:
1149   case ISD::SDIVFIX:
1150   case ISD::SDIVFIXSAT:
1151   case ISD::UDIVFIX:
1152   case ISD::UDIVFIXSAT: {
1153     unsigned Scale = Node->getConstantOperandVal(2);
1154     Action = TLI.getFixedPointOperationAction(Node->getOpcode(),
1155                                               Node->getValueType(0), Scale);
1156     break;
1157   }
1158   case ISD::MSCATTER:
1159     Action = TLI.getOperationAction(Node->getOpcode(),
1160                     cast<MaskedScatterSDNode>(Node)->getValue().getValueType());
1161     break;
1162   case ISD::MSTORE:
1163     Action = TLI.getOperationAction(Node->getOpcode(),
1164                     cast<MaskedStoreSDNode>(Node)->getValue().getValueType());
1165     break;
1166   case ISD::VECREDUCE_FADD:
1167   case ISD::VECREDUCE_FMUL:
1168   case ISD::VECREDUCE_ADD:
1169   case ISD::VECREDUCE_MUL:
1170   case ISD::VECREDUCE_AND:
1171   case ISD::VECREDUCE_OR:
1172   case ISD::VECREDUCE_XOR:
1173   case ISD::VECREDUCE_SMAX:
1174   case ISD::VECREDUCE_SMIN:
1175   case ISD::VECREDUCE_UMAX:
1176   case ISD::VECREDUCE_UMIN:
1177   case ISD::VECREDUCE_FMAX:
1178   case ISD::VECREDUCE_FMIN:
1179     Action = TLI.getOperationAction(
1180         Node->getOpcode(), Node->getOperand(0).getValueType());
1181     break;
1182   case ISD::VECREDUCE_SEQ_FADD:
1183     Action = TLI.getOperationAction(
1184         Node->getOpcode(), Node->getOperand(1).getValueType());
1185     break;
1186   default:
1187     if (Node->getOpcode() >= ISD::BUILTIN_OP_END) {
1188       Action = TargetLowering::Legal;
1189     } else {
1190       Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
1191     }
1192     break;
1193   }
1194 
1195   if (SimpleFinishLegalizing) {
1196     SDNode *NewNode = Node;
1197     switch (Node->getOpcode()) {
1198     default: break;
1199     case ISD::SHL:
1200     case ISD::SRL:
1201     case ISD::SRA:
1202     case ISD::ROTL:
1203     case ISD::ROTR: {
1204       // Legalizing shifts/rotates requires adjusting the shift amount
1205       // to the appropriate width.
1206       SDValue Op0 = Node->getOperand(0);
1207       SDValue Op1 = Node->getOperand(1);
1208       if (!Op1.getValueType().isVector()) {
1209         SDValue SAO = DAG.getShiftAmountOperand(Op0.getValueType(), Op1);
1210         // The getShiftAmountOperand() may create a new operand node or
1211         // return the existing one. If new operand is created we need
1212         // to update the parent node.
1213         // Do not try to legalize SAO here! It will be automatically legalized
1214         // in the next round.
1215         if (SAO != Op1)
1216           NewNode = DAG.UpdateNodeOperands(Node, Op0, SAO);
1217       }
1218     }
1219     break;
1220     case ISD::FSHL:
1221     case ISD::FSHR:
1222     case ISD::SRL_PARTS:
1223     case ISD::SRA_PARTS:
1224     case ISD::SHL_PARTS: {
1225       // Legalizing shifts/rotates requires adjusting the shift amount
1226       // to the appropriate width.
1227       SDValue Op0 = Node->getOperand(0);
1228       SDValue Op1 = Node->getOperand(1);
1229       SDValue Op2 = Node->getOperand(2);
1230       if (!Op2.getValueType().isVector()) {
1231         SDValue SAO = DAG.getShiftAmountOperand(Op0.getValueType(), Op2);
1232         // The getShiftAmountOperand() may create a new operand node or
1233         // return the existing one. If new operand is created we need
1234         // to update the parent node.
1235         if (SAO != Op2)
1236           NewNode = DAG.UpdateNodeOperands(Node, Op0, Op1, SAO);
1237       }
1238       break;
1239     }
1240     }
1241 
1242     if (NewNode != Node) {
1243       ReplaceNode(Node, NewNode);
1244       Node = NewNode;
1245     }
1246     switch (Action) {
1247     case TargetLowering::Legal:
1248       LLVM_DEBUG(dbgs() << "Legal node: nothing to do\n");
1249       return;
1250     case TargetLowering::Custom:
1251       LLVM_DEBUG(dbgs() << "Trying custom legalization\n");
1252       // FIXME: The handling for custom lowering with multiple results is
1253       // a complete mess.
1254       if (SDValue Res = TLI.LowerOperation(SDValue(Node, 0), DAG)) {
1255         if (!(Res.getNode() != Node || Res.getResNo() != 0))
1256           return;
1257 
1258         if (Node->getNumValues() == 1) {
1259           LLVM_DEBUG(dbgs() << "Successfully custom legalized node\n");
1260           // We can just directly replace this node with the lowered value.
1261           ReplaceNode(SDValue(Node, 0), Res);
1262           return;
1263         }
1264 
1265         SmallVector<SDValue, 8> ResultVals;
1266         for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
1267           ResultVals.push_back(Res.getValue(i));
1268         LLVM_DEBUG(dbgs() << "Successfully custom legalized node\n");
1269         ReplaceNode(Node, ResultVals.data());
1270         return;
1271       }
1272       LLVM_DEBUG(dbgs() << "Could not custom legalize node\n");
1273       LLVM_FALLTHROUGH;
1274     case TargetLowering::Expand:
1275       if (ExpandNode(Node))
1276         return;
1277       LLVM_FALLTHROUGH;
1278     case TargetLowering::LibCall:
1279       ConvertNodeToLibcall(Node);
1280       return;
1281     case TargetLowering::Promote:
1282       PromoteNode(Node);
1283       return;
1284     }
1285   }
1286 
1287   switch (Node->getOpcode()) {
1288   default:
1289 #ifndef NDEBUG
1290     dbgs() << "NODE: ";
1291     Node->dump( &DAG);
1292     dbgs() << "\n";
1293 #endif
1294     llvm_unreachable("Do not know how to legalize this operator!");
1295 
1296   case ISD::CALLSEQ_START:
1297   case ISD::CALLSEQ_END:
1298     break;
1299   case ISD::LOAD:
1300     return LegalizeLoadOps(Node);
1301   case ISD::STORE:
1302     return LegalizeStoreOps(Node);
1303   }
1304 }
1305 
1306 SDValue SelectionDAGLegalize::ExpandExtractFromVectorThroughStack(SDValue Op) {
1307   SDValue Vec = Op.getOperand(0);
1308   SDValue Idx = Op.getOperand(1);
1309   SDLoc dl(Op);
1310 
1311   // Before we generate a new store to a temporary stack slot, see if there is
1312   // already one that we can use. There often is because when we scalarize
1313   // vector operations (using SelectionDAG::UnrollVectorOp for example) a whole
1314   // series of EXTRACT_VECTOR_ELT nodes are generated, one for each element in
1315   // the vector. If all are expanded here, we don't want one store per vector
1316   // element.
1317 
1318   // Caches for hasPredecessorHelper
1319   SmallPtrSet<const SDNode *, 32> Visited;
1320   SmallVector<const SDNode *, 16> Worklist;
1321   Visited.insert(Op.getNode());
1322   Worklist.push_back(Idx.getNode());
1323   SDValue StackPtr, Ch;
1324   for (SDNode::use_iterator UI = Vec.getNode()->use_begin(),
1325        UE = Vec.getNode()->use_end(); UI != UE; ++UI) {
1326     SDNode *User = *UI;
1327     if (StoreSDNode *ST = dyn_cast<StoreSDNode>(User)) {
1328       if (ST->isIndexed() || ST->isTruncatingStore() ||
1329           ST->getValue() != Vec)
1330         continue;
1331 
1332       // Make sure that nothing else could have stored into the destination of
1333       // this store.
1334       if (!ST->getChain().reachesChainWithoutSideEffects(DAG.getEntryNode()))
1335         continue;
1336 
1337       // If the index is dependent on the store we will introduce a cycle when
1338       // creating the load (the load uses the index, and by replacing the chain
1339       // we will make the index dependent on the load). Also, the store might be
1340       // dependent on the extractelement and introduce a cycle when creating
1341       // the load.
1342       if (SDNode::hasPredecessorHelper(ST, Visited, Worklist) ||
1343           ST->hasPredecessor(Op.getNode()))
1344         continue;
1345 
1346       StackPtr = ST->getBasePtr();
1347       Ch = SDValue(ST, 0);
1348       break;
1349     }
1350   }
1351 
1352   EVT VecVT = Vec.getValueType();
1353 
1354   if (!Ch.getNode()) {
1355     // Store the value to a temporary stack slot, then LOAD the returned part.
1356     StackPtr = DAG.CreateStackTemporary(VecVT);
1357     Ch = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr,
1358                       MachinePointerInfo());
1359   }
1360 
1361   StackPtr = TLI.getVectorElementPointer(DAG, StackPtr, VecVT, Idx);
1362 
1363   SDValue NewLoad;
1364 
1365   if (Op.getValueType().isVector())
1366     NewLoad =
1367         DAG.getLoad(Op.getValueType(), dl, Ch, StackPtr, MachinePointerInfo());
1368   else
1369     NewLoad = DAG.getExtLoad(ISD::EXTLOAD, dl, Op.getValueType(), Ch, StackPtr,
1370                              MachinePointerInfo(),
1371                              VecVT.getVectorElementType());
1372 
1373   // Replace the chain going out of the store, by the one out of the load.
1374   DAG.ReplaceAllUsesOfValueWith(Ch, SDValue(NewLoad.getNode(), 1));
1375 
1376   // We introduced a cycle though, so update the loads operands, making sure
1377   // to use the original store's chain as an incoming chain.
1378   SmallVector<SDValue, 6> NewLoadOperands(NewLoad->op_begin(),
1379                                           NewLoad->op_end());
1380   NewLoadOperands[0] = Ch;
1381   NewLoad =
1382       SDValue(DAG.UpdateNodeOperands(NewLoad.getNode(), NewLoadOperands), 0);
1383   return NewLoad;
1384 }
1385 
1386 SDValue SelectionDAGLegalize::ExpandInsertToVectorThroughStack(SDValue Op) {
1387   assert(Op.getValueType().isVector() && "Non-vector insert subvector!");
1388 
1389   SDValue Vec  = Op.getOperand(0);
1390   SDValue Part = Op.getOperand(1);
1391   SDValue Idx  = Op.getOperand(2);
1392   SDLoc dl(Op);
1393 
1394   // Store the value to a temporary stack slot, then LOAD the returned part.
1395   EVT VecVT = Vec.getValueType();
1396   SDValue StackPtr = DAG.CreateStackTemporary(VecVT);
1397   int FI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
1398   MachinePointerInfo PtrInfo =
1399       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI);
1400 
1401   // First store the whole vector.
1402   SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr, PtrInfo);
1403 
1404   // Then store the inserted part.
1405   SDValue SubStackPtr = TLI.getVectorElementPointer(DAG, StackPtr, VecVT, Idx);
1406 
1407   // Store the subvector.
1408   Ch = DAG.getStore(
1409       Ch, dl, Part, SubStackPtr,
1410       MachinePointerInfo::getUnknownStack(DAG.getMachineFunction()));
1411 
1412   // Finally, load the updated vector.
1413   return DAG.getLoad(Op.getValueType(), dl, Ch, StackPtr, PtrInfo);
1414 }
1415 
1416 SDValue SelectionDAGLegalize::ExpandVectorBuildThroughStack(SDNode* Node) {
1417   assert((Node->getOpcode() == ISD::BUILD_VECTOR ||
1418           Node->getOpcode() == ISD::CONCAT_VECTORS) &&
1419          "Unexpected opcode!");
1420 
1421   // We can't handle this case efficiently.  Allocate a sufficiently
1422   // aligned object on the stack, store each operand into it, then load
1423   // the result as a vector.
1424   // Create the stack frame object.
1425   EVT VT = Node->getValueType(0);
1426   EVT MemVT = isa<BuildVectorSDNode>(Node) ? VT.getVectorElementType()
1427                                            : Node->getOperand(0).getValueType();
1428   SDLoc dl(Node);
1429   SDValue FIPtr = DAG.CreateStackTemporary(VT);
1430   int FI = cast<FrameIndexSDNode>(FIPtr.getNode())->getIndex();
1431   MachinePointerInfo PtrInfo =
1432       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI);
1433 
1434   // Emit a store of each element to the stack slot.
1435   SmallVector<SDValue, 8> Stores;
1436   unsigned TypeByteSize = MemVT.getSizeInBits() / 8;
1437   assert(TypeByteSize > 0 && "Vector element type too small for stack store!");
1438 
1439   // If the destination vector element type of a BUILD_VECTOR is narrower than
1440   // the source element type, only store the bits necessary.
1441   bool Truncate = isa<BuildVectorSDNode>(Node) &&
1442                   MemVT.bitsLT(Node->getOperand(0).getValueType());
1443 
1444   // Store (in the right endianness) the elements to memory.
1445   for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
1446     // Ignore undef elements.
1447     if (Node->getOperand(i).isUndef()) continue;
1448 
1449     unsigned Offset = TypeByteSize*i;
1450 
1451     SDValue Idx = DAG.getMemBasePlusOffset(FIPtr, TypeSize::Fixed(Offset), dl);
1452 
1453     if (Truncate)
1454       Stores.push_back(DAG.getTruncStore(DAG.getEntryNode(), dl,
1455                                          Node->getOperand(i), Idx,
1456                                          PtrInfo.getWithOffset(Offset), MemVT));
1457     else
1458       Stores.push_back(DAG.getStore(DAG.getEntryNode(), dl, Node->getOperand(i),
1459                                     Idx, PtrInfo.getWithOffset(Offset)));
1460   }
1461 
1462   SDValue StoreChain;
1463   if (!Stores.empty())    // Not all undef elements?
1464     StoreChain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Stores);
1465   else
1466     StoreChain = DAG.getEntryNode();
1467 
1468   // Result is a load from the stack slot.
1469   return DAG.getLoad(VT, dl, StoreChain, FIPtr, PtrInfo);
1470 }
1471 
1472 /// Bitcast a floating-point value to an integer value. Only bitcast the part
1473 /// containing the sign bit if the target has no integer value capable of
1474 /// holding all bits of the floating-point value.
1475 void SelectionDAGLegalize::getSignAsIntValue(FloatSignAsInt &State,
1476                                              const SDLoc &DL,
1477                                              SDValue Value) const {
1478   EVT FloatVT = Value.getValueType();
1479   unsigned NumBits = FloatVT.getScalarSizeInBits();
1480   State.FloatVT = FloatVT;
1481   EVT IVT = EVT::getIntegerVT(*DAG.getContext(), NumBits);
1482   // Convert to an integer of the same size.
1483   if (TLI.isTypeLegal(IVT)) {
1484     State.IntValue = DAG.getNode(ISD::BITCAST, DL, IVT, Value);
1485     State.SignMask = APInt::getSignMask(NumBits);
1486     State.SignBit = NumBits - 1;
1487     return;
1488   }
1489 
1490   auto &DataLayout = DAG.getDataLayout();
1491   // Store the float to memory, then load the sign part out as an integer.
1492   MVT LoadTy = TLI.getRegisterType(*DAG.getContext(), MVT::i8);
1493   // First create a temporary that is aligned for both the load and store.
1494   SDValue StackPtr = DAG.CreateStackTemporary(FloatVT, LoadTy);
1495   int FI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
1496   // Then store the float to it.
1497   State.FloatPtr = StackPtr;
1498   MachineFunction &MF = DAG.getMachineFunction();
1499   State.FloatPointerInfo = MachinePointerInfo::getFixedStack(MF, FI);
1500   State.Chain = DAG.getStore(DAG.getEntryNode(), DL, Value, State.FloatPtr,
1501                              State.FloatPointerInfo);
1502 
1503   SDValue IntPtr;
1504   if (DataLayout.isBigEndian()) {
1505     assert(FloatVT.isByteSized() && "Unsupported floating point type!");
1506     // Load out a legal integer with the same sign bit as the float.
1507     IntPtr = StackPtr;
1508     State.IntPointerInfo = State.FloatPointerInfo;
1509   } else {
1510     // Advance the pointer so that the loaded byte will contain the sign bit.
1511     unsigned ByteOffset = (NumBits / 8) - 1;
1512     IntPtr =
1513         DAG.getMemBasePlusOffset(StackPtr, TypeSize::Fixed(ByteOffset), DL);
1514     State.IntPointerInfo = MachinePointerInfo::getFixedStack(MF, FI,
1515                                                              ByteOffset);
1516   }
1517 
1518   State.IntPtr = IntPtr;
1519   State.IntValue = DAG.getExtLoad(ISD::EXTLOAD, DL, LoadTy, State.Chain, IntPtr,
1520                                   State.IntPointerInfo, MVT::i8);
1521   State.SignMask = APInt::getOneBitSet(LoadTy.getScalarSizeInBits(), 7);
1522   State.SignBit = 7;
1523 }
1524 
1525 /// Replace the integer value produced by getSignAsIntValue() with a new value
1526 /// and cast the result back to a floating-point type.
1527 SDValue SelectionDAGLegalize::modifySignAsInt(const FloatSignAsInt &State,
1528                                               const SDLoc &DL,
1529                                               SDValue NewIntValue) const {
1530   if (!State.Chain)
1531     return DAG.getNode(ISD::BITCAST, DL, State.FloatVT, NewIntValue);
1532 
1533   // Override the part containing the sign bit in the value stored on the stack.
1534   SDValue Chain = DAG.getTruncStore(State.Chain, DL, NewIntValue, State.IntPtr,
1535                                     State.IntPointerInfo, MVT::i8);
1536   return DAG.getLoad(State.FloatVT, DL, Chain, State.FloatPtr,
1537                      State.FloatPointerInfo);
1538 }
1539 
1540 SDValue SelectionDAGLegalize::ExpandFCOPYSIGN(SDNode *Node) const {
1541   SDLoc DL(Node);
1542   SDValue Mag = Node->getOperand(0);
1543   SDValue Sign = Node->getOperand(1);
1544 
1545   // Get sign bit into an integer value.
1546   FloatSignAsInt SignAsInt;
1547   getSignAsIntValue(SignAsInt, DL, Sign);
1548 
1549   EVT IntVT = SignAsInt.IntValue.getValueType();
1550   SDValue SignMask = DAG.getConstant(SignAsInt.SignMask, DL, IntVT);
1551   SDValue SignBit = DAG.getNode(ISD::AND, DL, IntVT, SignAsInt.IntValue,
1552                                 SignMask);
1553 
1554   // If FABS is legal transform FCOPYSIGN(x, y) => sign(x) ? -FABS(x) : FABS(X)
1555   EVT FloatVT = Mag.getValueType();
1556   if (TLI.isOperationLegalOrCustom(ISD::FABS, FloatVT) &&
1557       TLI.isOperationLegalOrCustom(ISD::FNEG, FloatVT)) {
1558     SDValue AbsValue = DAG.getNode(ISD::FABS, DL, FloatVT, Mag);
1559     SDValue NegValue = DAG.getNode(ISD::FNEG, DL, FloatVT, AbsValue);
1560     SDValue Cond = DAG.getSetCC(DL, getSetCCResultType(IntVT), SignBit,
1561                                 DAG.getConstant(0, DL, IntVT), ISD::SETNE);
1562     return DAG.getSelect(DL, FloatVT, Cond, NegValue, AbsValue);
1563   }
1564 
1565   // Transform Mag value to integer, and clear the sign bit.
1566   FloatSignAsInt MagAsInt;
1567   getSignAsIntValue(MagAsInt, DL, Mag);
1568   EVT MagVT = MagAsInt.IntValue.getValueType();
1569   SDValue ClearSignMask = DAG.getConstant(~MagAsInt.SignMask, DL, MagVT);
1570   SDValue ClearedSign = DAG.getNode(ISD::AND, DL, MagVT, MagAsInt.IntValue,
1571                                     ClearSignMask);
1572 
1573   // Get the signbit at the right position for MagAsInt.
1574   int ShiftAmount = SignAsInt.SignBit - MagAsInt.SignBit;
1575   EVT ShiftVT = IntVT;
1576   if (SignBit.getScalarValueSizeInBits() <
1577       ClearedSign.getScalarValueSizeInBits()) {
1578     SignBit = DAG.getNode(ISD::ZERO_EXTEND, DL, MagVT, SignBit);
1579     ShiftVT = MagVT;
1580   }
1581   if (ShiftAmount > 0) {
1582     SDValue ShiftCnst = DAG.getConstant(ShiftAmount, DL, ShiftVT);
1583     SignBit = DAG.getNode(ISD::SRL, DL, ShiftVT, SignBit, ShiftCnst);
1584   } else if (ShiftAmount < 0) {
1585     SDValue ShiftCnst = DAG.getConstant(-ShiftAmount, DL, ShiftVT);
1586     SignBit = DAG.getNode(ISD::SHL, DL, ShiftVT, SignBit, ShiftCnst);
1587   }
1588   if (SignBit.getScalarValueSizeInBits() >
1589       ClearedSign.getScalarValueSizeInBits()) {
1590     SignBit = DAG.getNode(ISD::TRUNCATE, DL, MagVT, SignBit);
1591   }
1592 
1593   // Store the part with the modified sign and convert back to float.
1594   SDValue CopiedSign = DAG.getNode(ISD::OR, DL, MagVT, ClearedSign, SignBit);
1595   return modifySignAsInt(MagAsInt, DL, CopiedSign);
1596 }
1597 
1598 SDValue SelectionDAGLegalize::ExpandFNEG(SDNode *Node) const {
1599   // Get the sign bit as an integer.
1600   SDLoc DL(Node);
1601   FloatSignAsInt SignAsInt;
1602   getSignAsIntValue(SignAsInt, DL, Node->getOperand(0));
1603   EVT IntVT = SignAsInt.IntValue.getValueType();
1604 
1605   // Flip the sign.
1606   SDValue SignMask = DAG.getConstant(SignAsInt.SignMask, DL, IntVT);
1607   SDValue SignFlip =
1608       DAG.getNode(ISD::XOR, DL, IntVT, SignAsInt.IntValue, SignMask);
1609 
1610   // Convert back to float.
1611   return modifySignAsInt(SignAsInt, DL, SignFlip);
1612 }
1613 
1614 SDValue SelectionDAGLegalize::ExpandFABS(SDNode *Node) const {
1615   SDLoc DL(Node);
1616   SDValue Value = Node->getOperand(0);
1617 
1618   // Transform FABS(x) => FCOPYSIGN(x, 0.0) if FCOPYSIGN is legal.
1619   EVT FloatVT = Value.getValueType();
1620   if (TLI.isOperationLegalOrCustom(ISD::FCOPYSIGN, FloatVT)) {
1621     SDValue Zero = DAG.getConstantFP(0.0, DL, FloatVT);
1622     return DAG.getNode(ISD::FCOPYSIGN, DL, FloatVT, Value, Zero);
1623   }
1624 
1625   // Transform value to integer, clear the sign bit and transform back.
1626   FloatSignAsInt ValueAsInt;
1627   getSignAsIntValue(ValueAsInt, DL, Value);
1628   EVT IntVT = ValueAsInt.IntValue.getValueType();
1629   SDValue ClearSignMask = DAG.getConstant(~ValueAsInt.SignMask, DL, IntVT);
1630   SDValue ClearedSign = DAG.getNode(ISD::AND, DL, IntVT, ValueAsInt.IntValue,
1631                                     ClearSignMask);
1632   return modifySignAsInt(ValueAsInt, DL, ClearedSign);
1633 }
1634 
1635 void SelectionDAGLegalize::ExpandDYNAMIC_STACKALLOC(SDNode* Node,
1636                                            SmallVectorImpl<SDValue> &Results) {
1637   Register SPReg = TLI.getStackPointerRegisterToSaveRestore();
1638   assert(SPReg && "Target cannot require DYNAMIC_STACKALLOC expansion and"
1639           " not tell us which reg is the stack pointer!");
1640   SDLoc dl(Node);
1641   EVT VT = Node->getValueType(0);
1642   SDValue Tmp1 = SDValue(Node, 0);
1643   SDValue Tmp2 = SDValue(Node, 1);
1644   SDValue Tmp3 = Node->getOperand(2);
1645   SDValue Chain = Tmp1.getOperand(0);
1646 
1647   // Chain the dynamic stack allocation so that it doesn't modify the stack
1648   // pointer when other instructions are using the stack.
1649   Chain = DAG.getCALLSEQ_START(Chain, 0, 0, dl);
1650 
1651   SDValue Size  = Tmp2.getOperand(1);
1652   SDValue SP = DAG.getCopyFromReg(Chain, dl, SPReg, VT);
1653   Chain = SP.getValue(1);
1654   Align Alignment = cast<ConstantSDNode>(Tmp3)->getAlignValue();
1655   const TargetFrameLowering *TFL = DAG.getSubtarget().getFrameLowering();
1656   unsigned Opc =
1657     TFL->getStackGrowthDirection() == TargetFrameLowering::StackGrowsUp ?
1658     ISD::ADD : ISD::SUB;
1659 
1660   Align StackAlign = TFL->getStackAlign();
1661   Tmp1 = DAG.getNode(Opc, dl, VT, SP, Size);       // Value
1662   if (Alignment > StackAlign)
1663     Tmp1 = DAG.getNode(ISD::AND, dl, VT, Tmp1,
1664                        DAG.getConstant(-Alignment.value(), dl, VT));
1665   Chain = DAG.getCopyToReg(Chain, dl, SPReg, Tmp1);     // Output chain
1666 
1667   Tmp2 = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(0, dl, true),
1668                             DAG.getIntPtrConstant(0, dl, true), SDValue(), dl);
1669 
1670   Results.push_back(Tmp1);
1671   Results.push_back(Tmp2);
1672 }
1673 
1674 /// Legalize a SETCC with given LHS and RHS and condition code CC on the current
1675 /// target.
1676 ///
1677 /// If the SETCC has been legalized using AND / OR, then the legalized node
1678 /// will be stored in LHS. RHS and CC will be set to SDValue(). NeedInvert
1679 /// will be set to false.
1680 ///
1681 /// If the SETCC has been legalized by using getSetCCSwappedOperands(),
1682 /// then the values of LHS and RHS will be swapped, CC will be set to the
1683 /// new condition, and NeedInvert will be set to false.
1684 ///
1685 /// If the SETCC has been legalized using the inverse condcode, then LHS and
1686 /// RHS will be unchanged, CC will set to the inverted condcode, and NeedInvert
1687 /// will be set to true. The caller must invert the result of the SETCC with
1688 /// SelectionDAG::getLogicalNOT() or take equivalent action to swap the effect
1689 /// of a true/false result.
1690 ///
1691 /// \returns true if the SetCC has been legalized, false if it hasn't.
1692 bool SelectionDAGLegalize::LegalizeSetCCCondCode(
1693     EVT VT, SDValue &LHS, SDValue &RHS, SDValue &CC, bool &NeedInvert,
1694     const SDLoc &dl, SDValue &Chain, bool IsSignaling) {
1695   MVT OpVT = LHS.getSimpleValueType();
1696   ISD::CondCode CCCode = cast<CondCodeSDNode>(CC)->get();
1697   NeedInvert = false;
1698   switch (TLI.getCondCodeAction(CCCode, OpVT)) {
1699   default: llvm_unreachable("Unknown condition code action!");
1700   case TargetLowering::Legal:
1701     // Nothing to do.
1702     break;
1703   case TargetLowering::Expand: {
1704     ISD::CondCode InvCC = ISD::getSetCCSwappedOperands(CCCode);
1705     if (TLI.isCondCodeLegalOrCustom(InvCC, OpVT)) {
1706       std::swap(LHS, RHS);
1707       CC = DAG.getCondCode(InvCC);
1708       return true;
1709     }
1710     // Swapping operands didn't work. Try inverting the condition.
1711     bool NeedSwap = false;
1712     InvCC = getSetCCInverse(CCCode, OpVT);
1713     if (!TLI.isCondCodeLegalOrCustom(InvCC, OpVT)) {
1714       // If inverting the condition is not enough, try swapping operands
1715       // on top of it.
1716       InvCC = ISD::getSetCCSwappedOperands(InvCC);
1717       NeedSwap = true;
1718     }
1719     if (TLI.isCondCodeLegalOrCustom(InvCC, OpVT)) {
1720       CC = DAG.getCondCode(InvCC);
1721       NeedInvert = true;
1722       if (NeedSwap)
1723         std::swap(LHS, RHS);
1724       return true;
1725     }
1726 
1727     ISD::CondCode CC1 = ISD::SETCC_INVALID, CC2 = ISD::SETCC_INVALID;
1728     unsigned Opc = 0;
1729     switch (CCCode) {
1730     default: llvm_unreachable("Don't know how to expand this condition!");
1731     case ISD::SETUO:
1732         if (TLI.isCondCodeLegal(ISD::SETUNE, OpVT)) {
1733           CC1 = ISD::SETUNE; CC2 = ISD::SETUNE; Opc = ISD::OR;
1734           break;
1735         }
1736         assert(TLI.isCondCodeLegal(ISD::SETOEQ, OpVT) &&
1737                "If SETUE is expanded, SETOEQ or SETUNE must be legal!");
1738         NeedInvert = true;
1739         LLVM_FALLTHROUGH;
1740     case ISD::SETO:
1741         assert(TLI.isCondCodeLegal(ISD::SETOEQ, OpVT)
1742             && "If SETO is expanded, SETOEQ must be legal!");
1743         CC1 = ISD::SETOEQ; CC2 = ISD::SETOEQ; Opc = ISD::AND; break;
1744     case ISD::SETONE:
1745     case ISD::SETUEQ:
1746         // If the SETUO or SETO CC isn't legal, we might be able to use
1747         // SETOGT || SETOLT, inverting the result for SETUEQ. We only need one
1748         // of SETOGT/SETOLT to be legal, the other can be emulated by swapping
1749         // the operands.
1750         CC2 = ((unsigned)CCCode & 0x8U) ? ISD::SETUO : ISD::SETO;
1751         if (!TLI.isCondCodeLegal(CC2, OpVT) &&
1752             (TLI.isCondCodeLegal(ISD::SETOGT, OpVT) ||
1753              TLI.isCondCodeLegal(ISD::SETOLT, OpVT))) {
1754           CC1 = ISD::SETOGT;
1755           CC2 = ISD::SETOLT;
1756           Opc = ISD::OR;
1757           NeedInvert = ((unsigned)CCCode & 0x8U);
1758           break;
1759         }
1760         LLVM_FALLTHROUGH;
1761     case ISD::SETOEQ:
1762     case ISD::SETOGT:
1763     case ISD::SETOGE:
1764     case ISD::SETOLT:
1765     case ISD::SETOLE:
1766     case ISD::SETUNE:
1767     case ISD::SETUGT:
1768     case ISD::SETUGE:
1769     case ISD::SETULT:
1770     case ISD::SETULE:
1771         // If we are floating point, assign and break, otherwise fall through.
1772         if (!OpVT.isInteger()) {
1773           // We can use the 4th bit to tell if we are the unordered
1774           // or ordered version of the opcode.
1775           CC2 = ((unsigned)CCCode & 0x8U) ? ISD::SETUO : ISD::SETO;
1776           Opc = ((unsigned)CCCode & 0x8U) ? ISD::OR : ISD::AND;
1777           CC1 = (ISD::CondCode)(((int)CCCode & 0x7) | 0x10);
1778           break;
1779         }
1780         // Fallthrough if we are unsigned integer.
1781         LLVM_FALLTHROUGH;
1782     case ISD::SETLE:
1783     case ISD::SETGT:
1784     case ISD::SETGE:
1785     case ISD::SETLT:
1786     case ISD::SETNE:
1787     case ISD::SETEQ:
1788       // If all combinations of inverting the condition and swapping operands
1789       // didn't work then we have no means to expand the condition.
1790       llvm_unreachable("Don't know how to expand this condition!");
1791     }
1792 
1793     SDValue SetCC1, SetCC2;
1794     if (CCCode != ISD::SETO && CCCode != ISD::SETUO) {
1795       // If we aren't the ordered or unorder operation,
1796       // then the pattern is (LHS CC1 RHS) Opc (LHS CC2 RHS).
1797       SetCC1 = DAG.getSetCC(dl, VT, LHS, RHS, CC1, Chain,
1798                             IsSignaling);
1799       SetCC2 = DAG.getSetCC(dl, VT, LHS, RHS, CC2, Chain,
1800                             IsSignaling);
1801     } else {
1802       // Otherwise, the pattern is (LHS CC1 LHS) Opc (RHS CC2 RHS)
1803       SetCC1 = DAG.getSetCC(dl, VT, LHS, LHS, CC1, Chain,
1804                             IsSignaling);
1805       SetCC2 = DAG.getSetCC(dl, VT, RHS, RHS, CC2, Chain,
1806                             IsSignaling);
1807     }
1808     if (Chain)
1809       Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, SetCC1.getValue(1),
1810                           SetCC2.getValue(1));
1811     LHS = DAG.getNode(Opc, dl, VT, SetCC1, SetCC2);
1812     RHS = SDValue();
1813     CC  = SDValue();
1814     return true;
1815   }
1816   }
1817   return false;
1818 }
1819 
1820 /// Emit a store/load combination to the stack.  This stores
1821 /// SrcOp to a stack slot of type SlotVT, truncating it if needed.  It then does
1822 /// a load from the stack slot to DestVT, extending it if needed.
1823 /// The resultant code need not be legal.
1824 SDValue SelectionDAGLegalize::EmitStackConvert(SDValue SrcOp, EVT SlotVT,
1825                                                EVT DestVT, const SDLoc &dl) {
1826   return EmitStackConvert(SrcOp, SlotVT, DestVT, dl, DAG.getEntryNode());
1827 }
1828 
1829 SDValue SelectionDAGLegalize::EmitStackConvert(SDValue SrcOp, EVT SlotVT,
1830                                                EVT DestVT, const SDLoc &dl,
1831                                                SDValue Chain) {
1832   unsigned SrcSize = SrcOp.getValueSizeInBits();
1833   unsigned SlotSize = SlotVT.getSizeInBits();
1834   unsigned DestSize = DestVT.getSizeInBits();
1835   Type *DestType = DestVT.getTypeForEVT(*DAG.getContext());
1836   Align DestAlign = DAG.getDataLayout().getPrefTypeAlign(DestType);
1837 
1838   // Don't convert with stack if the load/store is expensive.
1839   if ((SrcSize > SlotSize &&
1840        !TLI.isTruncStoreLegalOrCustom(SrcOp.getValueType(), SlotVT)) ||
1841       (SlotSize < DestSize &&
1842        !TLI.isLoadExtLegalOrCustom(ISD::EXTLOAD, DestVT, SlotVT)))
1843     return SDValue();
1844 
1845   // Create the stack frame object.
1846   Align SrcAlign = DAG.getDataLayout().getPrefTypeAlign(
1847       SrcOp.getValueType().getTypeForEVT(*DAG.getContext()));
1848   SDValue FIPtr = DAG.CreateStackTemporary(SlotVT.getStoreSize(), SrcAlign);
1849 
1850   FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(FIPtr);
1851   int SPFI = StackPtrFI->getIndex();
1852   MachinePointerInfo PtrInfo =
1853       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI);
1854 
1855   // Emit a store to the stack slot.  Use a truncstore if the input value is
1856   // later than DestVT.
1857   SDValue Store;
1858 
1859   if (SrcSize > SlotSize)
1860     Store = DAG.getTruncStore(Chain, dl, SrcOp, FIPtr, PtrInfo,
1861                               SlotVT, SrcAlign);
1862   else {
1863     assert(SrcSize == SlotSize && "Invalid store");
1864     Store =
1865         DAG.getStore(Chain, dl, SrcOp, FIPtr, PtrInfo, SrcAlign);
1866   }
1867 
1868   // Result is a load from the stack slot.
1869   if (SlotSize == DestSize)
1870     return DAG.getLoad(DestVT, dl, Store, FIPtr, PtrInfo, DestAlign);
1871 
1872   assert(SlotSize < DestSize && "Unknown extension!");
1873   return DAG.getExtLoad(ISD::EXTLOAD, dl, DestVT, Store, FIPtr, PtrInfo, SlotVT,
1874                         DestAlign);
1875 }
1876 
1877 SDValue SelectionDAGLegalize::ExpandSCALAR_TO_VECTOR(SDNode *Node) {
1878   SDLoc dl(Node);
1879   // Create a vector sized/aligned stack slot, store the value to element #0,
1880   // then load the whole vector back out.
1881   SDValue StackPtr = DAG.CreateStackTemporary(Node->getValueType(0));
1882 
1883   FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(StackPtr);
1884   int SPFI = StackPtrFI->getIndex();
1885 
1886   SDValue Ch = DAG.getTruncStore(
1887       DAG.getEntryNode(), dl, Node->getOperand(0), StackPtr,
1888       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI),
1889       Node->getValueType(0).getVectorElementType());
1890   return DAG.getLoad(
1891       Node->getValueType(0), dl, Ch, StackPtr,
1892       MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), SPFI));
1893 }
1894 
1895 static bool
1896 ExpandBVWithShuffles(SDNode *Node, SelectionDAG &DAG,
1897                      const TargetLowering &TLI, SDValue &Res) {
1898   unsigned NumElems = Node->getNumOperands();
1899   SDLoc dl(Node);
1900   EVT VT = Node->getValueType(0);
1901 
1902   // Try to group the scalars into pairs, shuffle the pairs together, then
1903   // shuffle the pairs of pairs together, etc. until the vector has
1904   // been built. This will work only if all of the necessary shuffle masks
1905   // are legal.
1906 
1907   // We do this in two phases; first to check the legality of the shuffles,
1908   // and next, assuming that all shuffles are legal, to create the new nodes.
1909   for (int Phase = 0; Phase < 2; ++Phase) {
1910     SmallVector<std::pair<SDValue, SmallVector<int, 16>>, 16> IntermedVals,
1911                                                               NewIntermedVals;
1912     for (unsigned i = 0; i < NumElems; ++i) {
1913       SDValue V = Node->getOperand(i);
1914       if (V.isUndef())
1915         continue;
1916 
1917       SDValue Vec;
1918       if (Phase)
1919         Vec = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, V);
1920       IntermedVals.push_back(std::make_pair(Vec, SmallVector<int, 16>(1, i)));
1921     }
1922 
1923     while (IntermedVals.size() > 2) {
1924       NewIntermedVals.clear();
1925       for (unsigned i = 0, e = (IntermedVals.size() & ~1u); i < e; i += 2) {
1926         // This vector and the next vector are shuffled together (simply to
1927         // append the one to the other).
1928         SmallVector<int, 16> ShuffleVec(NumElems, -1);
1929 
1930         SmallVector<int, 16> FinalIndices;
1931         FinalIndices.reserve(IntermedVals[i].second.size() +
1932                              IntermedVals[i+1].second.size());
1933 
1934         int k = 0;
1935         for (unsigned j = 0, f = IntermedVals[i].second.size(); j != f;
1936              ++j, ++k) {
1937           ShuffleVec[k] = j;
1938           FinalIndices.push_back(IntermedVals[i].second[j]);
1939         }
1940         for (unsigned j = 0, f = IntermedVals[i+1].second.size(); j != f;
1941              ++j, ++k) {
1942           ShuffleVec[k] = NumElems + j;
1943           FinalIndices.push_back(IntermedVals[i+1].second[j]);
1944         }
1945 
1946         SDValue Shuffle;
1947         if (Phase)
1948           Shuffle = DAG.getVectorShuffle(VT, dl, IntermedVals[i].first,
1949                                          IntermedVals[i+1].first,
1950                                          ShuffleVec);
1951         else if (!TLI.isShuffleMaskLegal(ShuffleVec, VT))
1952           return false;
1953         NewIntermedVals.push_back(
1954             std::make_pair(Shuffle, std::move(FinalIndices)));
1955       }
1956 
1957       // If we had an odd number of defined values, then append the last
1958       // element to the array of new vectors.
1959       if ((IntermedVals.size() & 1) != 0)
1960         NewIntermedVals.push_back(IntermedVals.back());
1961 
1962       IntermedVals.swap(NewIntermedVals);
1963     }
1964 
1965     assert(IntermedVals.size() <= 2 && IntermedVals.size() > 0 &&
1966            "Invalid number of intermediate vectors");
1967     SDValue Vec1 = IntermedVals[0].first;
1968     SDValue Vec2;
1969     if (IntermedVals.size() > 1)
1970       Vec2 = IntermedVals[1].first;
1971     else if (Phase)
1972       Vec2 = DAG.getUNDEF(VT);
1973 
1974     SmallVector<int, 16> ShuffleVec(NumElems, -1);
1975     for (unsigned i = 0, e = IntermedVals[0].second.size(); i != e; ++i)
1976       ShuffleVec[IntermedVals[0].second[i]] = i;
1977     for (unsigned i = 0, e = IntermedVals[1].second.size(); i != e; ++i)
1978       ShuffleVec[IntermedVals[1].second[i]] = NumElems + i;
1979 
1980     if (Phase)
1981       Res = DAG.getVectorShuffle(VT, dl, Vec1, Vec2, ShuffleVec);
1982     else if (!TLI.isShuffleMaskLegal(ShuffleVec, VT))
1983       return false;
1984   }
1985 
1986   return true;
1987 }
1988 
1989 /// Expand a BUILD_VECTOR node on targets that don't
1990 /// support the operation, but do support the resultant vector type.
1991 SDValue SelectionDAGLegalize::ExpandBUILD_VECTOR(SDNode *Node) {
1992   unsigned NumElems = Node->getNumOperands();
1993   SDValue Value1, Value2;
1994   SDLoc dl(Node);
1995   EVT VT = Node->getValueType(0);
1996   EVT OpVT = Node->getOperand(0).getValueType();
1997   EVT EltVT = VT.getVectorElementType();
1998 
1999   // If the only non-undef value is the low element, turn this into a
2000   // SCALAR_TO_VECTOR node.  If this is { X, X, X, X }, determine X.
2001   bool isOnlyLowElement = true;
2002   bool MoreThanTwoValues = false;
2003   bool isConstant = true;
2004   for (unsigned i = 0; i < NumElems; ++i) {
2005     SDValue V = Node->getOperand(i);
2006     if (V.isUndef())
2007       continue;
2008     if (i > 0)
2009       isOnlyLowElement = false;
2010     if (!isa<ConstantFPSDNode>(V) && !isa<ConstantSDNode>(V))
2011       isConstant = false;
2012 
2013     if (!Value1.getNode()) {
2014       Value1 = V;
2015     } else if (!Value2.getNode()) {
2016       if (V != Value1)
2017         Value2 = V;
2018     } else if (V != Value1 && V != Value2) {
2019       MoreThanTwoValues = true;
2020     }
2021   }
2022 
2023   if (!Value1.getNode())
2024     return DAG.getUNDEF(VT);
2025 
2026   if (isOnlyLowElement)
2027     return DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Node->getOperand(0));
2028 
2029   // If all elements are constants, create a load from the constant pool.
2030   if (isConstant) {
2031     SmallVector<Constant*, 16> CV;
2032     for (unsigned i = 0, e = NumElems; i != e; ++i) {
2033       if (ConstantFPSDNode *V =
2034           dyn_cast<ConstantFPSDNode>(Node->getOperand(i))) {
2035         CV.push_back(const_cast<ConstantFP *>(V->getConstantFPValue()));
2036       } else if (ConstantSDNode *V =
2037                  dyn_cast<ConstantSDNode>(Node->getOperand(i))) {
2038         if (OpVT==EltVT)
2039           CV.push_back(const_cast<ConstantInt *>(V->getConstantIntValue()));
2040         else {
2041           // If OpVT and EltVT don't match, EltVT is not legal and the
2042           // element values have been promoted/truncated earlier.  Undo this;
2043           // we don't want a v16i8 to become a v16i32 for example.
2044           const ConstantInt *CI = V->getConstantIntValue();
2045           CV.push_back(ConstantInt::get(EltVT.getTypeForEVT(*DAG.getContext()),
2046                                         CI->getZExtValue()));
2047         }
2048       } else {
2049         assert(Node->getOperand(i).isUndef());
2050         Type *OpNTy = EltVT.getTypeForEVT(*DAG.getContext());
2051         CV.push_back(UndefValue::get(OpNTy));
2052       }
2053     }
2054     Constant *CP = ConstantVector::get(CV);
2055     SDValue CPIdx =
2056         DAG.getConstantPool(CP, TLI.getPointerTy(DAG.getDataLayout()));
2057     Align Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlign();
2058     return DAG.getLoad(
2059         VT, dl, DAG.getEntryNode(), CPIdx,
2060         MachinePointerInfo::getConstantPool(DAG.getMachineFunction()),
2061         Alignment);
2062   }
2063 
2064   SmallSet<SDValue, 16> DefinedValues;
2065   for (unsigned i = 0; i < NumElems; ++i) {
2066     if (Node->getOperand(i).isUndef())
2067       continue;
2068     DefinedValues.insert(Node->getOperand(i));
2069   }
2070 
2071   if (TLI.shouldExpandBuildVectorWithShuffles(VT, DefinedValues.size())) {
2072     if (!MoreThanTwoValues) {
2073       SmallVector<int, 8> ShuffleVec(NumElems, -1);
2074       for (unsigned i = 0; i < NumElems; ++i) {
2075         SDValue V = Node->getOperand(i);
2076         if (V.isUndef())
2077           continue;
2078         ShuffleVec[i] = V == Value1 ? 0 : NumElems;
2079       }
2080       if (TLI.isShuffleMaskLegal(ShuffleVec, Node->getValueType(0))) {
2081         // Get the splatted value into the low element of a vector register.
2082         SDValue Vec1 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value1);
2083         SDValue Vec2;
2084         if (Value2.getNode())
2085           Vec2 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value2);
2086         else
2087           Vec2 = DAG.getUNDEF(VT);
2088 
2089         // Return shuffle(LowValVec, undef, <0,0,0,0>)
2090         return DAG.getVectorShuffle(VT, dl, Vec1, Vec2, ShuffleVec);
2091       }
2092     } else {
2093       SDValue Res;
2094       if (ExpandBVWithShuffles(Node, DAG, TLI, Res))
2095         return Res;
2096     }
2097   }
2098 
2099   // Otherwise, we can't handle this case efficiently.
2100   return ExpandVectorBuildThroughStack(Node);
2101 }
2102 
2103 SDValue SelectionDAGLegalize::ExpandSPLAT_VECTOR(SDNode *Node) {
2104   SDLoc DL(Node);
2105   EVT VT = Node->getValueType(0);
2106   SDValue SplatVal = Node->getOperand(0);
2107 
2108   return DAG.getSplatBuildVector(VT, DL, SplatVal);
2109 }
2110 
2111 // Expand a node into a call to a libcall.  If the result value
2112 // does not fit into a register, return the lo part and set the hi part to the
2113 // by-reg argument.  If it does fit into a single register, return the result
2114 // and leave the Hi part unset.
2115 SDValue SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, SDNode *Node,
2116                                             bool isSigned) {
2117   TargetLowering::ArgListTy Args;
2118   TargetLowering::ArgListEntry Entry;
2119   for (const SDValue &Op : Node->op_values()) {
2120     EVT ArgVT = Op.getValueType();
2121     Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
2122     Entry.Node = Op;
2123     Entry.Ty = ArgTy;
2124     Entry.IsSExt = TLI.shouldSignExtendTypeInLibCall(ArgVT, isSigned);
2125     Entry.IsZExt = !TLI.shouldSignExtendTypeInLibCall(ArgVT, isSigned);
2126     Args.push_back(Entry);
2127   }
2128   SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
2129                                          TLI.getPointerTy(DAG.getDataLayout()));
2130 
2131   EVT RetVT = Node->getValueType(0);
2132   Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
2133 
2134   // By default, the input chain to this libcall is the entry node of the
2135   // function. If the libcall is going to be emitted as a tail call then
2136   // TLI.isUsedByReturnOnly will change it to the right chain if the return
2137   // node which is being folded has a non-entry input chain.
2138   SDValue InChain = DAG.getEntryNode();
2139 
2140   // isTailCall may be true since the callee does not reference caller stack
2141   // frame. Check if it's in the right position and that the return types match.
2142   SDValue TCChain = InChain;
2143   const Function &F = DAG.getMachineFunction().getFunction();
2144   bool isTailCall =
2145       TLI.isInTailCallPosition(DAG, Node, TCChain) &&
2146       (RetTy == F.getReturnType() || F.getReturnType()->isVoidTy());
2147   if (isTailCall)
2148     InChain = TCChain;
2149 
2150   TargetLowering::CallLoweringInfo CLI(DAG);
2151   bool signExtend = TLI.shouldSignExtendTypeInLibCall(RetVT, isSigned);
2152   CLI.setDebugLoc(SDLoc(Node))
2153       .setChain(InChain)
2154       .setLibCallee(TLI.getLibcallCallingConv(LC), RetTy, Callee,
2155                     std::move(Args))
2156       .setTailCall(isTailCall)
2157       .setSExtResult(signExtend)
2158       .setZExtResult(!signExtend)
2159       .setIsPostTypeLegalization(true);
2160 
2161   std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
2162 
2163   if (!CallInfo.second.getNode()) {
2164     LLVM_DEBUG(dbgs() << "Created tailcall: "; DAG.getRoot().dump(&DAG));
2165     // It's a tailcall, return the chain (which is the DAG root).
2166     return DAG.getRoot();
2167   }
2168 
2169   LLVM_DEBUG(dbgs() << "Created libcall: "; CallInfo.first.dump(&DAG));
2170   return CallInfo.first;
2171 }
2172 
2173 void SelectionDAGLegalize::ExpandFPLibCall(SDNode* Node,
2174                                            RTLIB::Libcall Call_F32,
2175                                            RTLIB::Libcall Call_F64,
2176                                            RTLIB::Libcall Call_F80,
2177                                            RTLIB::Libcall Call_F128,
2178                                            RTLIB::Libcall Call_PPCF128,
2179                                            SmallVectorImpl<SDValue> &Results) {
2180   RTLIB::Libcall LC;
2181   switch (Node->getSimpleValueType(0).SimpleTy) {
2182   default: llvm_unreachable("Unexpected request for libcall!");
2183   case MVT::f32: LC = Call_F32; break;
2184   case MVT::f64: LC = Call_F64; break;
2185   case MVT::f80: LC = Call_F80; break;
2186   case MVT::f128: LC = Call_F128; break;
2187   case MVT::ppcf128: LC = Call_PPCF128; break;
2188   }
2189 
2190   if (Node->isStrictFPOpcode()) {
2191     EVT RetVT = Node->getValueType(0);
2192     SmallVector<SDValue, 4> Ops(Node->op_begin() + 1, Node->op_end());
2193     TargetLowering::MakeLibCallOptions CallOptions;
2194     // FIXME: This doesn't support tail calls.
2195     std::pair<SDValue, SDValue> Tmp = TLI.makeLibCall(DAG, LC, RetVT,
2196                                                       Ops, CallOptions,
2197                                                       SDLoc(Node),
2198                                                       Node->getOperand(0));
2199     Results.push_back(Tmp.first);
2200     Results.push_back(Tmp.second);
2201   } else {
2202     SDValue Tmp = ExpandLibCall(LC, Node, false);
2203     Results.push_back(Tmp);
2204   }
2205 }
2206 
2207 SDValue SelectionDAGLegalize::ExpandIntLibCall(SDNode* Node, bool isSigned,
2208                                                RTLIB::Libcall Call_I8,
2209                                                RTLIB::Libcall Call_I16,
2210                                                RTLIB::Libcall Call_I32,
2211                                                RTLIB::Libcall Call_I64,
2212                                                RTLIB::Libcall Call_I128) {
2213   RTLIB::Libcall LC;
2214   switch (Node->getSimpleValueType(0).SimpleTy) {
2215   default: llvm_unreachable("Unexpected request for libcall!");
2216   case MVT::i8:   LC = Call_I8; break;
2217   case MVT::i16:  LC = Call_I16; break;
2218   case MVT::i32:  LC = Call_I32; break;
2219   case MVT::i64:  LC = Call_I64; break;
2220   case MVT::i128: LC = Call_I128; break;
2221   }
2222   return ExpandLibCall(LC, Node, isSigned);
2223 }
2224 
2225 /// Expand the node to a libcall based on first argument type (for instance
2226 /// lround and its variant).
2227 void SelectionDAGLegalize::ExpandArgFPLibCall(SDNode* Node,
2228                                             RTLIB::Libcall Call_F32,
2229                                             RTLIB::Libcall Call_F64,
2230                                             RTLIB::Libcall Call_F80,
2231                                             RTLIB::Libcall Call_F128,
2232                                             RTLIB::Libcall Call_PPCF128,
2233                                             SmallVectorImpl<SDValue> &Results) {
2234   EVT InVT = Node->getOperand(Node->isStrictFPOpcode() ? 1 : 0).getValueType();
2235 
2236   RTLIB::Libcall LC;
2237   switch (InVT.getSimpleVT().SimpleTy) {
2238   default: llvm_unreachable("Unexpected request for libcall!");
2239   case MVT::f32:     LC = Call_F32; break;
2240   case MVT::f64:     LC = Call_F64; break;
2241   case MVT::f80:     LC = Call_F80; break;
2242   case MVT::f128:    LC = Call_F128; break;
2243   case MVT::ppcf128: LC = Call_PPCF128; break;
2244   }
2245 
2246   if (Node->isStrictFPOpcode()) {
2247     EVT RetVT = Node->getValueType(0);
2248     SmallVector<SDValue, 4> Ops(Node->op_begin() + 1, Node->op_end());
2249     TargetLowering::MakeLibCallOptions CallOptions;
2250     // FIXME: This doesn't support tail calls.
2251     std::pair<SDValue, SDValue> Tmp = TLI.makeLibCall(DAG, LC, RetVT,
2252                                                       Ops, CallOptions,
2253                                                       SDLoc(Node),
2254                                                       Node->getOperand(0));
2255     Results.push_back(Tmp.first);
2256     Results.push_back(Tmp.second);
2257   } else {
2258     SDValue Tmp = ExpandLibCall(LC, Node, false);
2259     Results.push_back(Tmp);
2260   }
2261 }
2262 
2263 /// Issue libcalls to __{u}divmod to compute div / rem pairs.
2264 void
2265 SelectionDAGLegalize::ExpandDivRemLibCall(SDNode *Node,
2266                                           SmallVectorImpl<SDValue> &Results) {
2267   unsigned Opcode = Node->getOpcode();
2268   bool isSigned = Opcode == ISD::SDIVREM;
2269 
2270   RTLIB::Libcall LC;
2271   switch (Node->getSimpleValueType(0).SimpleTy) {
2272   default: llvm_unreachable("Unexpected request for libcall!");
2273   case MVT::i8:   LC= isSigned ? RTLIB::SDIVREM_I8  : RTLIB::UDIVREM_I8;  break;
2274   case MVT::i16:  LC= isSigned ? RTLIB::SDIVREM_I16 : RTLIB::UDIVREM_I16; break;
2275   case MVT::i32:  LC= isSigned ? RTLIB::SDIVREM_I32 : RTLIB::UDIVREM_I32; break;
2276   case MVT::i64:  LC= isSigned ? RTLIB::SDIVREM_I64 : RTLIB::UDIVREM_I64; break;
2277   case MVT::i128: LC= isSigned ? RTLIB::SDIVREM_I128:RTLIB::UDIVREM_I128; break;
2278   }
2279 
2280   // The input chain to this libcall is the entry node of the function.
2281   // Legalizing the call will automatically add the previous call to the
2282   // dependence.
2283   SDValue InChain = DAG.getEntryNode();
2284 
2285   EVT RetVT = Node->getValueType(0);
2286   Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
2287 
2288   TargetLowering::ArgListTy Args;
2289   TargetLowering::ArgListEntry Entry;
2290   for (const SDValue &Op : Node->op_values()) {
2291     EVT ArgVT = Op.getValueType();
2292     Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
2293     Entry.Node = Op;
2294     Entry.Ty = ArgTy;
2295     Entry.IsSExt = isSigned;
2296     Entry.IsZExt = !isSigned;
2297     Args.push_back(Entry);
2298   }
2299 
2300   // Also pass the return address of the remainder.
2301   SDValue FIPtr = DAG.CreateStackTemporary(RetVT);
2302   Entry.Node = FIPtr;
2303   Entry.Ty = RetTy->getPointerTo();
2304   Entry.IsSExt = isSigned;
2305   Entry.IsZExt = !isSigned;
2306   Args.push_back(Entry);
2307 
2308   SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
2309                                          TLI.getPointerTy(DAG.getDataLayout()));
2310 
2311   SDLoc dl(Node);
2312   TargetLowering::CallLoweringInfo CLI(DAG);
2313   CLI.setDebugLoc(dl)
2314       .setChain(InChain)
2315       .setLibCallee(TLI.getLibcallCallingConv(LC), RetTy, Callee,
2316                     std::move(Args))
2317       .setSExtResult(isSigned)
2318       .setZExtResult(!isSigned);
2319 
2320   std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
2321 
2322   // Remainder is loaded back from the stack frame.
2323   SDValue Rem =
2324       DAG.getLoad(RetVT, dl, CallInfo.second, FIPtr, MachinePointerInfo());
2325   Results.push_back(CallInfo.first);
2326   Results.push_back(Rem);
2327 }
2328 
2329 /// Return true if sincos libcall is available.
2330 static bool isSinCosLibcallAvailable(SDNode *Node, const TargetLowering &TLI) {
2331   RTLIB::Libcall LC;
2332   switch (Node->getSimpleValueType(0).SimpleTy) {
2333   default: llvm_unreachable("Unexpected request for libcall!");
2334   case MVT::f32:     LC = RTLIB::SINCOS_F32; break;
2335   case MVT::f64:     LC = RTLIB::SINCOS_F64; break;
2336   case MVT::f80:     LC = RTLIB::SINCOS_F80; break;
2337   case MVT::f128:    LC = RTLIB::SINCOS_F128; break;
2338   case MVT::ppcf128: LC = RTLIB::SINCOS_PPCF128; break;
2339   }
2340   return TLI.getLibcallName(LC) != nullptr;
2341 }
2342 
2343 /// Only issue sincos libcall if both sin and cos are needed.
2344 static bool useSinCos(SDNode *Node) {
2345   unsigned OtherOpcode = Node->getOpcode() == ISD::FSIN
2346     ? ISD::FCOS : ISD::FSIN;
2347 
2348   SDValue Op0 = Node->getOperand(0);
2349   for (SDNode::use_iterator UI = Op0.getNode()->use_begin(),
2350        UE = Op0.getNode()->use_end(); UI != UE; ++UI) {
2351     SDNode *User = *UI;
2352     if (User == Node)
2353       continue;
2354     // The other user might have been turned into sincos already.
2355     if (User->getOpcode() == OtherOpcode || User->getOpcode() == ISD::FSINCOS)
2356       return true;
2357   }
2358   return false;
2359 }
2360 
2361 /// Issue libcalls to sincos to compute sin / cos pairs.
2362 void
2363 SelectionDAGLegalize::ExpandSinCosLibCall(SDNode *Node,
2364                                           SmallVectorImpl<SDValue> &Results) {
2365   RTLIB::Libcall LC;
2366   switch (Node->getSimpleValueType(0).SimpleTy) {
2367   default: llvm_unreachable("Unexpected request for libcall!");
2368   case MVT::f32:     LC = RTLIB::SINCOS_F32; break;
2369   case MVT::f64:     LC = RTLIB::SINCOS_F64; break;
2370   case MVT::f80:     LC = RTLIB::SINCOS_F80; break;
2371   case MVT::f128:    LC = RTLIB::SINCOS_F128; break;
2372   case MVT::ppcf128: LC = RTLIB::SINCOS_PPCF128; break;
2373   }
2374 
2375   // The input chain to this libcall is the entry node of the function.
2376   // Legalizing the call will automatically add the previous call to the
2377   // dependence.
2378   SDValue InChain = DAG.getEntryNode();
2379 
2380   EVT RetVT = Node->getValueType(0);
2381   Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
2382 
2383   TargetLowering::ArgListTy Args;
2384   TargetLowering::ArgListEntry Entry;
2385 
2386   // Pass the argument.
2387   Entry.Node = Node->getOperand(0);
2388   Entry.Ty = RetTy;
2389   Entry.IsSExt = false;
2390   Entry.IsZExt = false;
2391   Args.push_back(Entry);
2392 
2393   // Pass the return address of sin.
2394   SDValue SinPtr = DAG.CreateStackTemporary(RetVT);
2395   Entry.Node = SinPtr;
2396   Entry.Ty = RetTy->getPointerTo();
2397   Entry.IsSExt = false;
2398   Entry.IsZExt = false;
2399   Args.push_back(Entry);
2400 
2401   // Also pass the return address of the cos.
2402   SDValue CosPtr = DAG.CreateStackTemporary(RetVT);
2403   Entry.Node = CosPtr;
2404   Entry.Ty = RetTy->getPointerTo();
2405   Entry.IsSExt = false;
2406   Entry.IsZExt = false;
2407   Args.push_back(Entry);
2408 
2409   SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
2410                                          TLI.getPointerTy(DAG.getDataLayout()));
2411 
2412   SDLoc dl(Node);
2413   TargetLowering::CallLoweringInfo CLI(DAG);
2414   CLI.setDebugLoc(dl).setChain(InChain).setLibCallee(
2415       TLI.getLibcallCallingConv(LC), Type::getVoidTy(*DAG.getContext()), Callee,
2416       std::move(Args));
2417 
2418   std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
2419 
2420   Results.push_back(
2421       DAG.getLoad(RetVT, dl, CallInfo.second, SinPtr, MachinePointerInfo()));
2422   Results.push_back(
2423       DAG.getLoad(RetVT, dl, CallInfo.second, CosPtr, MachinePointerInfo()));
2424 }
2425 
2426 /// This function is responsible for legalizing a
2427 /// INT_TO_FP operation of the specified operand when the target requests that
2428 /// we expand it.  At this point, we know that the result and operand types are
2429 /// legal for the target.
2430 SDValue SelectionDAGLegalize::ExpandLegalINT_TO_FP(SDNode *Node,
2431                                                    SDValue &Chain) {
2432   bool isSigned = (Node->getOpcode() == ISD::STRICT_SINT_TO_FP ||
2433                    Node->getOpcode() == ISD::SINT_TO_FP);
2434   EVT DestVT = Node->getValueType(0);
2435   SDLoc dl(Node);
2436   unsigned OpNo = Node->isStrictFPOpcode() ? 1 : 0;
2437   SDValue Op0 = Node->getOperand(OpNo);
2438   EVT SrcVT = Op0.getValueType();
2439 
2440   // TODO: Should any fast-math-flags be set for the created nodes?
2441   LLVM_DEBUG(dbgs() << "Legalizing INT_TO_FP\n");
2442   if (SrcVT == MVT::i32 && TLI.isTypeLegal(MVT::f64) &&
2443       (DestVT.bitsLE(MVT::f64) ||
2444        TLI.isOperationLegal(Node->isStrictFPOpcode() ? ISD::STRICT_FP_EXTEND
2445                                                      : ISD::FP_EXTEND,
2446                             DestVT))) {
2447     LLVM_DEBUG(dbgs() << "32-bit [signed|unsigned] integer to float/double "
2448                          "expansion\n");
2449 
2450     // Get the stack frame index of a 8 byte buffer.
2451     SDValue StackSlot = DAG.CreateStackTemporary(MVT::f64);
2452 
2453     SDValue Lo = Op0;
2454     // if signed map to unsigned space
2455     if (isSigned) {
2456       // Invert sign bit (signed to unsigned mapping).
2457       Lo = DAG.getNode(ISD::XOR, dl, MVT::i32, Lo,
2458                        DAG.getConstant(0x80000000u, dl, MVT::i32));
2459     }
2460     // Initial hi portion of constructed double.
2461     SDValue Hi = DAG.getConstant(0x43300000u, dl, MVT::i32);
2462 
2463     // If this a big endian target, swap the lo and high data.
2464     if (DAG.getDataLayout().isBigEndian())
2465       std::swap(Lo, Hi);
2466 
2467     SDValue MemChain = DAG.getEntryNode();
2468 
2469     // Store the lo of the constructed double.
2470     SDValue Store1 = DAG.getStore(MemChain, dl, Lo, StackSlot,
2471                                   MachinePointerInfo());
2472     // Store the hi of the constructed double.
2473     SDValue HiPtr = DAG.getMemBasePlusOffset(StackSlot, TypeSize::Fixed(4), dl);
2474     SDValue Store2 =
2475         DAG.getStore(MemChain, dl, Hi, HiPtr, MachinePointerInfo());
2476     MemChain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Store1, Store2);
2477 
2478     // load the constructed double
2479     SDValue Load =
2480         DAG.getLoad(MVT::f64, dl, MemChain, StackSlot, MachinePointerInfo());
2481     // FP constant to bias correct the final result
2482     SDValue Bias = DAG.getConstantFP(isSigned ?
2483                                      BitsToDouble(0x4330000080000000ULL) :
2484                                      BitsToDouble(0x4330000000000000ULL),
2485                                      dl, MVT::f64);
2486     // Subtract the bias and get the final result.
2487     SDValue Sub;
2488     SDValue Result;
2489     if (Node->isStrictFPOpcode()) {
2490       Sub = DAG.getNode(ISD::STRICT_FSUB, dl, {MVT::f64, MVT::Other},
2491                         {Node->getOperand(0), Load, Bias});
2492       Chain = Sub.getValue(1);
2493       if (DestVT != Sub.getValueType()) {
2494         std::pair<SDValue, SDValue> ResultPair;
2495         ResultPair =
2496             DAG.getStrictFPExtendOrRound(Sub, Chain, dl, DestVT);
2497         Result = ResultPair.first;
2498         Chain = ResultPair.second;
2499       }
2500       else
2501         Result = Sub;
2502     } else {
2503       Sub = DAG.getNode(ISD::FSUB, dl, MVT::f64, Load, Bias);
2504       Result = DAG.getFPExtendOrRound(Sub, dl, DestVT);
2505     }
2506     return Result;
2507   }
2508 
2509   if (isSigned)
2510     return SDValue();
2511 
2512   // TODO: Generalize this for use with other types.
2513   if (((SrcVT == MVT::i32 || SrcVT == MVT::i64) && DestVT == MVT::f32) ||
2514       (SrcVT == MVT::i64 && DestVT == MVT::f64)) {
2515     LLVM_DEBUG(dbgs() << "Converting unsigned i32/i64 to f32/f64\n");
2516     // For unsigned conversions, convert them to signed conversions using the
2517     // algorithm from the x86_64 __floatundisf in compiler_rt. That method
2518     // should be valid for i32->f32 as well.
2519 
2520     // More generally this transform should be valid if there are 3 more bits
2521     // in the integer type than the significand. Rounding uses the first bit
2522     // after the width of the significand and the OR of all bits after that. So
2523     // we need to be able to OR the shifted out bit into one of the bits that
2524     // participate in the OR.
2525 
2526     // TODO: This really should be implemented using a branch rather than a
2527     // select.  We happen to get lucky and machinesink does the right
2528     // thing most of the time.  This would be a good candidate for a
2529     // pseudo-op, or, even better, for whole-function isel.
2530     EVT SetCCVT = getSetCCResultType(SrcVT);
2531 
2532     SDValue SignBitTest = DAG.getSetCC(
2533         dl, SetCCVT, Op0, DAG.getConstant(0, dl, SrcVT), ISD::SETLT);
2534 
2535     EVT ShiftVT = TLI.getShiftAmountTy(SrcVT, DAG.getDataLayout());
2536     SDValue ShiftConst = DAG.getConstant(1, dl, ShiftVT);
2537     SDValue Shr = DAG.getNode(ISD::SRL, dl, SrcVT, Op0, ShiftConst);
2538     SDValue AndConst = DAG.getConstant(1, dl, SrcVT);
2539     SDValue And = DAG.getNode(ISD::AND, dl, SrcVT, Op0, AndConst);
2540     SDValue Or = DAG.getNode(ISD::OR, dl, SrcVT, And, Shr);
2541 
2542     SDValue Slow, Fast;
2543     if (Node->isStrictFPOpcode()) {
2544       // In strict mode, we must avoid spurious exceptions, and therefore
2545       // must make sure to only emit a single STRICT_SINT_TO_FP.
2546       SDValue InCvt = DAG.getSelect(dl, SrcVT, SignBitTest, Or, Op0);
2547       Fast = DAG.getNode(ISD::STRICT_SINT_TO_FP, dl, { DestVT, MVT::Other },
2548                          { Node->getOperand(0), InCvt });
2549       Slow = DAG.getNode(ISD::STRICT_FADD, dl, { DestVT, MVT::Other },
2550                          { Fast.getValue(1), Fast, Fast });
2551       Chain = Slow.getValue(1);
2552       // The STRICT_SINT_TO_FP inherits the exception mode from the
2553       // incoming STRICT_UINT_TO_FP node; the STRICT_FADD node can
2554       // never raise any exception.
2555       SDNodeFlags Flags;
2556       Flags.setNoFPExcept(Node->getFlags().hasNoFPExcept());
2557       Fast->setFlags(Flags);
2558       Flags.setNoFPExcept(true);
2559       Slow->setFlags(Flags);
2560     } else {
2561       SDValue SignCvt = DAG.getNode(ISD::SINT_TO_FP, dl, DestVT, Or);
2562       Slow = DAG.getNode(ISD::FADD, dl, DestVT, SignCvt, SignCvt);
2563       Fast = DAG.getNode(ISD::SINT_TO_FP, dl, DestVT, Op0);
2564     }
2565 
2566     return DAG.getSelect(dl, DestVT, SignBitTest, Slow, Fast);
2567   }
2568 
2569   // Don't expand it if there isn't cheap fadd.
2570   if (!TLI.isOperationLegalOrCustom(
2571           Node->isStrictFPOpcode() ? ISD::STRICT_FADD : ISD::FADD, DestVT))
2572     return SDValue();
2573 
2574   // The following optimization is valid only if every value in SrcVT (when
2575   // treated as signed) is representable in DestVT.  Check that the mantissa
2576   // size of DestVT is >= than the number of bits in SrcVT -1.
2577   assert(APFloat::semanticsPrecision(DAG.EVTToAPFloatSemantics(DestVT)) >=
2578              SrcVT.getSizeInBits() - 1 &&
2579          "Cannot perform lossless SINT_TO_FP!");
2580 
2581   SDValue Tmp1;
2582   if (Node->isStrictFPOpcode()) {
2583     Tmp1 = DAG.getNode(ISD::STRICT_SINT_TO_FP, dl, { DestVT, MVT::Other },
2584                        { Node->getOperand(0), Op0 });
2585   } else
2586     Tmp1 = DAG.getNode(ISD::SINT_TO_FP, dl, DestVT, Op0);
2587 
2588   SDValue SignSet = DAG.getSetCC(dl, getSetCCResultType(SrcVT), Op0,
2589                                  DAG.getConstant(0, dl, SrcVT), ISD::SETLT);
2590   SDValue Zero = DAG.getIntPtrConstant(0, dl),
2591           Four = DAG.getIntPtrConstant(4, dl);
2592   SDValue CstOffset = DAG.getSelect(dl, Zero.getValueType(),
2593                                     SignSet, Four, Zero);
2594 
2595   // If the sign bit of the integer is set, the large number will be treated
2596   // as a negative number.  To counteract this, the dynamic code adds an
2597   // offset depending on the data type.
2598   uint64_t FF;
2599   switch (SrcVT.getSimpleVT().SimpleTy) {
2600   default:
2601     return SDValue();
2602   case MVT::i8 : FF = 0x43800000ULL; break;  // 2^8  (as a float)
2603   case MVT::i16: FF = 0x47800000ULL; break;  // 2^16 (as a float)
2604   case MVT::i32: FF = 0x4F800000ULL; break;  // 2^32 (as a float)
2605   case MVT::i64: FF = 0x5F800000ULL; break;  // 2^64 (as a float)
2606   }
2607   if (DAG.getDataLayout().isLittleEndian())
2608     FF <<= 32;
2609   Constant *FudgeFactor = ConstantInt::get(
2610                                        Type::getInt64Ty(*DAG.getContext()), FF);
2611 
2612   SDValue CPIdx =
2613       DAG.getConstantPool(FudgeFactor, TLI.getPointerTy(DAG.getDataLayout()));
2614   Align Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlign();
2615   CPIdx = DAG.getNode(ISD::ADD, dl, CPIdx.getValueType(), CPIdx, CstOffset);
2616   Alignment = commonAlignment(Alignment, 4);
2617   SDValue FudgeInReg;
2618   if (DestVT == MVT::f32)
2619     FudgeInReg = DAG.getLoad(
2620         MVT::f32, dl, DAG.getEntryNode(), CPIdx,
2621         MachinePointerInfo::getConstantPool(DAG.getMachineFunction()),
2622         Alignment);
2623   else {
2624     SDValue Load = DAG.getExtLoad(
2625         ISD::EXTLOAD, dl, DestVT, DAG.getEntryNode(), CPIdx,
2626         MachinePointerInfo::getConstantPool(DAG.getMachineFunction()), MVT::f32,
2627         Alignment);
2628     HandleSDNode Handle(Load);
2629     LegalizeOp(Load.getNode());
2630     FudgeInReg = Handle.getValue();
2631   }
2632 
2633   if (Node->isStrictFPOpcode()) {
2634     SDValue Result = DAG.getNode(ISD::STRICT_FADD, dl, { DestVT, MVT::Other },
2635                                  { Tmp1.getValue(1), Tmp1, FudgeInReg });
2636     Chain = Result.getValue(1);
2637     return Result;
2638   }
2639 
2640   return DAG.getNode(ISD::FADD, dl, DestVT, Tmp1, FudgeInReg);
2641 }
2642 
2643 /// This function is responsible for legalizing a
2644 /// *INT_TO_FP operation of the specified operand when the target requests that
2645 /// we promote it.  At this point, we know that the result and operand types are
2646 /// legal for the target, and that there is a legal UINT_TO_FP or SINT_TO_FP
2647 /// operation that takes a larger input.
2648 void SelectionDAGLegalize::PromoteLegalINT_TO_FP(
2649     SDNode *N, const SDLoc &dl, SmallVectorImpl<SDValue> &Results) {
2650   bool IsStrict = N->isStrictFPOpcode();
2651   bool IsSigned = N->getOpcode() == ISD::SINT_TO_FP ||
2652                   N->getOpcode() == ISD::STRICT_SINT_TO_FP;
2653   EVT DestVT = N->getValueType(0);
2654   SDValue LegalOp = N->getOperand(IsStrict ? 1 : 0);
2655   unsigned UIntOp = IsStrict ? ISD::STRICT_UINT_TO_FP : ISD::UINT_TO_FP;
2656   unsigned SIntOp = IsStrict ? ISD::STRICT_SINT_TO_FP : ISD::SINT_TO_FP;
2657 
2658   // First step, figure out the appropriate *INT_TO_FP operation to use.
2659   EVT NewInTy = LegalOp.getValueType();
2660 
2661   unsigned OpToUse = 0;
2662 
2663   // Scan for the appropriate larger type to use.
2664   while (true) {
2665     NewInTy = (MVT::SimpleValueType)(NewInTy.getSimpleVT().SimpleTy+1);
2666     assert(NewInTy.isInteger() && "Ran out of possibilities!");
2667 
2668     // If the target supports SINT_TO_FP of this type, use it.
2669     if (TLI.isOperationLegalOrCustom(SIntOp, NewInTy)) {
2670       OpToUse = SIntOp;
2671       break;
2672     }
2673     if (IsSigned)
2674       continue;
2675 
2676     // If the target supports UINT_TO_FP of this type, use it.
2677     if (TLI.isOperationLegalOrCustom(UIntOp, NewInTy)) {
2678       OpToUse = UIntOp;
2679       break;
2680     }
2681 
2682     // Otherwise, try a larger type.
2683   }
2684 
2685   // Okay, we found the operation and type to use.  Zero extend our input to the
2686   // desired type then run the operation on it.
2687   if (IsStrict) {
2688     SDValue Res =
2689         DAG.getNode(OpToUse, dl, {DestVT, MVT::Other},
2690                     {N->getOperand(0),
2691                      DAG.getNode(IsSigned ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND,
2692                                  dl, NewInTy, LegalOp)});
2693     Results.push_back(Res);
2694     Results.push_back(Res.getValue(1));
2695     return;
2696   }
2697 
2698   Results.push_back(
2699       DAG.getNode(OpToUse, dl, DestVT,
2700                   DAG.getNode(IsSigned ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND,
2701                               dl, NewInTy, LegalOp)));
2702 }
2703 
2704 /// This function is responsible for legalizing a
2705 /// FP_TO_*INT operation of the specified operand when the target requests that
2706 /// we promote it.  At this point, we know that the result and operand types are
2707 /// legal for the target, and that there is a legal FP_TO_UINT or FP_TO_SINT
2708 /// operation that returns a larger result.
2709 void SelectionDAGLegalize::PromoteLegalFP_TO_INT(SDNode *N, const SDLoc &dl,
2710                                                  SmallVectorImpl<SDValue> &Results) {
2711   bool IsStrict = N->isStrictFPOpcode();
2712   bool IsSigned = N->getOpcode() == ISD::FP_TO_SINT ||
2713                   N->getOpcode() == ISD::STRICT_FP_TO_SINT;
2714   EVT DestVT = N->getValueType(0);
2715   SDValue LegalOp = N->getOperand(IsStrict ? 1 : 0);
2716   // First step, figure out the appropriate FP_TO*INT operation to use.
2717   EVT NewOutTy = DestVT;
2718 
2719   unsigned OpToUse = 0;
2720 
2721   // Scan for the appropriate larger type to use.
2722   while (true) {
2723     NewOutTy = (MVT::SimpleValueType)(NewOutTy.getSimpleVT().SimpleTy+1);
2724     assert(NewOutTy.isInteger() && "Ran out of possibilities!");
2725 
2726     // A larger signed type can hold all unsigned values of the requested type,
2727     // so using FP_TO_SINT is valid
2728     OpToUse = IsStrict ? ISD::STRICT_FP_TO_SINT : ISD::FP_TO_SINT;
2729     if (TLI.isOperationLegalOrCustom(OpToUse, NewOutTy))
2730       break;
2731 
2732     // However, if the value may be < 0.0, we *must* use some FP_TO_SINT.
2733     OpToUse = IsStrict ? ISD::STRICT_FP_TO_UINT : ISD::FP_TO_UINT;
2734     if (!IsSigned && TLI.isOperationLegalOrCustom(OpToUse, NewOutTy))
2735       break;
2736 
2737     // Otherwise, try a larger type.
2738   }
2739 
2740   // Okay, we found the operation and type to use.
2741   SDValue Operation;
2742   if (IsStrict) {
2743     SDVTList VTs = DAG.getVTList(NewOutTy, MVT::Other);
2744     Operation = DAG.getNode(OpToUse, dl, VTs, N->getOperand(0), LegalOp);
2745   } else
2746     Operation = DAG.getNode(OpToUse, dl, NewOutTy, LegalOp);
2747 
2748   // Truncate the result of the extended FP_TO_*INT operation to the desired
2749   // size.
2750   SDValue Trunc = DAG.getNode(ISD::TRUNCATE, dl, DestVT, Operation);
2751   Results.push_back(Trunc);
2752   if (IsStrict)
2753     Results.push_back(Operation.getValue(1));
2754 }
2755 
2756 /// Promote FP_TO_*INT_SAT operation to a larger result type. At this point
2757 /// the result and operand types are legal and there must be a legal
2758 /// FP_TO_*INT_SAT operation for a larger result type.
2759 SDValue SelectionDAGLegalize::PromoteLegalFP_TO_INT_SAT(SDNode *Node,
2760                                                         const SDLoc &dl) {
2761   unsigned Opcode = Node->getOpcode();
2762 
2763   // Scan for the appropriate larger type to use.
2764   EVT NewOutTy = Node->getValueType(0);
2765   while (true) {
2766     NewOutTy = (MVT::SimpleValueType)(NewOutTy.getSimpleVT().SimpleTy + 1);
2767     assert(NewOutTy.isInteger() && "Ran out of possibilities!");
2768 
2769     if (TLI.isOperationLegalOrCustom(Opcode, NewOutTy))
2770       break;
2771   }
2772 
2773   // Saturation width is determined by second operand, so we don't have to
2774   // perform any fixup and can directly truncate the result.
2775   SDValue Result = DAG.getNode(Opcode, dl, NewOutTy, Node->getOperand(0),
2776                                Node->getOperand(1));
2777   return DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0), Result);
2778 }
2779 
2780 /// Legalize a BITREVERSE scalar/vector operation as a series of mask + shifts.
2781 SDValue SelectionDAGLegalize::ExpandBITREVERSE(SDValue Op, const SDLoc &dl) {
2782   EVT VT = Op.getValueType();
2783   EVT SHVT = TLI.getShiftAmountTy(VT, DAG.getDataLayout());
2784   unsigned Sz = VT.getScalarSizeInBits();
2785 
2786   SDValue Tmp, Tmp2, Tmp3;
2787 
2788   // If we can, perform BSWAP first and then the mask+swap the i4, then i2
2789   // and finally the i1 pairs.
2790   // TODO: We can easily support i4/i2 legal types if any target ever does.
2791   if (Sz >= 8 && isPowerOf2_32(Sz)) {
2792     // Create the masks - repeating the pattern every byte.
2793     APInt MaskHi4 = APInt::getSplat(Sz, APInt(8, 0xF0));
2794     APInt MaskHi2 = APInt::getSplat(Sz, APInt(8, 0xCC));
2795     APInt MaskHi1 = APInt::getSplat(Sz, APInt(8, 0xAA));
2796     APInt MaskLo4 = APInt::getSplat(Sz, APInt(8, 0x0F));
2797     APInt MaskLo2 = APInt::getSplat(Sz, APInt(8, 0x33));
2798     APInt MaskLo1 = APInt::getSplat(Sz, APInt(8, 0x55));
2799 
2800     // BSWAP if the type is wider than a single byte.
2801     Tmp = (Sz > 8 ? DAG.getNode(ISD::BSWAP, dl, VT, Op) : Op);
2802 
2803     // swap i4: ((V & 0xF0) >> 4) | ((V & 0x0F) << 4)
2804     Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp, DAG.getConstant(MaskHi4, dl, VT));
2805     Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp, DAG.getConstant(MaskLo4, dl, VT));
2806     Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Tmp2, DAG.getConstant(4, dl, SHVT));
2807     Tmp3 = DAG.getNode(ISD::SHL, dl, VT, Tmp3, DAG.getConstant(4, dl, SHVT));
2808     Tmp = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp3);
2809 
2810     // swap i2: ((V & 0xCC) >> 2) | ((V & 0x33) << 2)
2811     Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp, DAG.getConstant(MaskHi2, dl, VT));
2812     Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp, DAG.getConstant(MaskLo2, dl, VT));
2813     Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Tmp2, DAG.getConstant(2, dl, SHVT));
2814     Tmp3 = DAG.getNode(ISD::SHL, dl, VT, Tmp3, DAG.getConstant(2, dl, SHVT));
2815     Tmp = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp3);
2816 
2817     // swap i1: ((V & 0xAA) >> 1) | ((V & 0x55) << 1)
2818     Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp, DAG.getConstant(MaskHi1, dl, VT));
2819     Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp, DAG.getConstant(MaskLo1, dl, VT));
2820     Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Tmp2, DAG.getConstant(1, dl, SHVT));
2821     Tmp3 = DAG.getNode(ISD::SHL, dl, VT, Tmp3, DAG.getConstant(1, dl, SHVT));
2822     Tmp = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp3);
2823     return Tmp;
2824   }
2825 
2826   Tmp = DAG.getConstant(0, dl, VT);
2827   for (unsigned I = 0, J = Sz-1; I < Sz; ++I, --J) {
2828     if (I < J)
2829       Tmp2 =
2830           DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(J - I, dl, SHVT));
2831     else
2832       Tmp2 =
2833           DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(I - J, dl, SHVT));
2834 
2835     APInt Shift(Sz, 1);
2836     Shift <<= J;
2837     Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(Shift, dl, VT));
2838     Tmp = DAG.getNode(ISD::OR, dl, VT, Tmp, Tmp2);
2839   }
2840 
2841   return Tmp;
2842 }
2843 
2844 /// Open code the operations for BSWAP of the specified operation.
2845 SDValue SelectionDAGLegalize::ExpandBSWAP(SDValue Op, const SDLoc &dl) {
2846   EVT VT = Op.getValueType();
2847   EVT SHVT = TLI.getShiftAmountTy(VT, DAG.getDataLayout());
2848   SDValue Tmp1, Tmp2, Tmp3, Tmp4, Tmp5, Tmp6, Tmp7, Tmp8;
2849   switch (VT.getSimpleVT().getScalarType().SimpleTy) {
2850   default: llvm_unreachable("Unhandled Expand type in BSWAP!");
2851   case MVT::i16:
2852     // Use a rotate by 8. This can be further expanded if necessary.
2853     return DAG.getNode(ISD::ROTL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
2854   case MVT::i32:
2855     Tmp4 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
2856     Tmp3 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
2857     Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
2858     Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
2859     Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3,
2860                        DAG.getConstant(0xFF0000, dl, VT));
2861     Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(0xFF00, dl, VT));
2862     Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
2863     Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
2864     return DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
2865   case MVT::i64:
2866     Tmp8 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(56, dl, SHVT));
2867     Tmp7 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(40, dl, SHVT));
2868     Tmp6 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
2869     Tmp5 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
2870     Tmp4 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, dl, SHVT));
2871     Tmp3 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, dl, SHVT));
2872     Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(40, dl, SHVT));
2873     Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(56, dl, SHVT));
2874     Tmp7 = DAG.getNode(ISD::AND, dl, VT, Tmp7,
2875                        DAG.getConstant(255ULL<<48, dl, VT));
2876     Tmp6 = DAG.getNode(ISD::AND, dl, VT, Tmp6,
2877                        DAG.getConstant(255ULL<<40, dl, VT));
2878     Tmp5 = DAG.getNode(ISD::AND, dl, VT, Tmp5,
2879                        DAG.getConstant(255ULL<<32, dl, VT));
2880     Tmp4 = DAG.getNode(ISD::AND, dl, VT, Tmp4,
2881                        DAG.getConstant(255ULL<<24, dl, VT));
2882     Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3,
2883                        DAG.getConstant(255ULL<<16, dl, VT));
2884     Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2,
2885                        DAG.getConstant(255ULL<<8 , dl, VT));
2886     Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp7);
2887     Tmp6 = DAG.getNode(ISD::OR, dl, VT, Tmp6, Tmp5);
2888     Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
2889     Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
2890     Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp6);
2891     Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
2892     return DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp4);
2893   }
2894 }
2895 
2896 /// Open code the operations for PARITY of the specified operation.
2897 SDValue SelectionDAGLegalize::ExpandPARITY(SDValue Op, const SDLoc &dl) {
2898   EVT VT = Op.getValueType();
2899   EVT ShVT = TLI.getShiftAmountTy(VT, DAG.getDataLayout());
2900   unsigned Sz = VT.getScalarSizeInBits();
2901 
2902   // If CTPOP is legal, use it. Otherwise use shifts and xor.
2903   SDValue Result;
2904   if (TLI.isOperationLegal(ISD::CTPOP, VT)) {
2905     Result = DAG.getNode(ISD::CTPOP, dl, VT, Op);
2906   } else {
2907     Result = Op;
2908     for (unsigned i = Log2_32_Ceil(Sz); i != 0;) {
2909       SDValue Shift = DAG.getNode(ISD::SRL, dl, VT, Result,
2910                                   DAG.getConstant(1ULL << (--i), dl, ShVT));
2911       Result = DAG.getNode(ISD::XOR, dl, VT, Result, Shift);
2912     }
2913   }
2914 
2915   return DAG.getNode(ISD::AND, dl, VT, Result, DAG.getConstant(1, dl, VT));
2916 }
2917 
2918 bool SelectionDAGLegalize::ExpandNode(SDNode *Node) {
2919   LLVM_DEBUG(dbgs() << "Trying to expand node\n");
2920   SmallVector<SDValue, 8> Results;
2921   SDLoc dl(Node);
2922   SDValue Tmp1, Tmp2, Tmp3, Tmp4;
2923   bool NeedInvert;
2924   switch (Node->getOpcode()) {
2925   case ISD::ABS:
2926     if (TLI.expandABS(Node, Tmp1, DAG))
2927       Results.push_back(Tmp1);
2928     break;
2929   case ISD::CTPOP:
2930     if (TLI.expandCTPOP(Node, Tmp1, DAG))
2931       Results.push_back(Tmp1);
2932     break;
2933   case ISD::CTLZ:
2934   case ISD::CTLZ_ZERO_UNDEF:
2935     if (TLI.expandCTLZ(Node, Tmp1, DAG))
2936       Results.push_back(Tmp1);
2937     break;
2938   case ISD::CTTZ:
2939   case ISD::CTTZ_ZERO_UNDEF:
2940     if (TLI.expandCTTZ(Node, Tmp1, DAG))
2941       Results.push_back(Tmp1);
2942     break;
2943   case ISD::BITREVERSE:
2944     Results.push_back(ExpandBITREVERSE(Node->getOperand(0), dl));
2945     break;
2946   case ISD::BSWAP:
2947     Results.push_back(ExpandBSWAP(Node->getOperand(0), dl));
2948     break;
2949   case ISD::PARITY:
2950     Results.push_back(ExpandPARITY(Node->getOperand(0), dl));
2951     break;
2952   case ISD::FRAMEADDR:
2953   case ISD::RETURNADDR:
2954   case ISD::FRAME_TO_ARGS_OFFSET:
2955     Results.push_back(DAG.getConstant(0, dl, Node->getValueType(0)));
2956     break;
2957   case ISD::EH_DWARF_CFA: {
2958     SDValue CfaArg = DAG.getSExtOrTrunc(Node->getOperand(0), dl,
2959                                         TLI.getPointerTy(DAG.getDataLayout()));
2960     SDValue Offset = DAG.getNode(ISD::ADD, dl,
2961                                  CfaArg.getValueType(),
2962                                  DAG.getNode(ISD::FRAME_TO_ARGS_OFFSET, dl,
2963                                              CfaArg.getValueType()),
2964                                  CfaArg);
2965     SDValue FA = DAG.getNode(
2966         ISD::FRAMEADDR, dl, TLI.getPointerTy(DAG.getDataLayout()),
2967         DAG.getConstant(0, dl, TLI.getPointerTy(DAG.getDataLayout())));
2968     Results.push_back(DAG.getNode(ISD::ADD, dl, FA.getValueType(),
2969                                   FA, Offset));
2970     break;
2971   }
2972   case ISD::FLT_ROUNDS_:
2973     Results.push_back(DAG.getConstant(1, dl, Node->getValueType(0)));
2974     Results.push_back(Node->getOperand(0));
2975     break;
2976   case ISD::EH_RETURN:
2977   case ISD::EH_LABEL:
2978   case ISD::PREFETCH:
2979   case ISD::VAEND:
2980   case ISD::EH_SJLJ_LONGJMP:
2981     // If the target didn't expand these, there's nothing to do, so just
2982     // preserve the chain and be done.
2983     Results.push_back(Node->getOperand(0));
2984     break;
2985   case ISD::READCYCLECOUNTER:
2986     // If the target didn't expand this, just return 'zero' and preserve the
2987     // chain.
2988     Results.append(Node->getNumValues() - 1,
2989                    DAG.getConstant(0, dl, Node->getValueType(0)));
2990     Results.push_back(Node->getOperand(0));
2991     break;
2992   case ISD::EH_SJLJ_SETJMP:
2993     // If the target didn't expand this, just return 'zero' and preserve the
2994     // chain.
2995     Results.push_back(DAG.getConstant(0, dl, MVT::i32));
2996     Results.push_back(Node->getOperand(0));
2997     break;
2998   case ISD::ATOMIC_LOAD: {
2999     // There is no libcall for atomic load; fake it with ATOMIC_CMP_SWAP.
3000     SDValue Zero = DAG.getConstant(0, dl, Node->getValueType(0));
3001     SDVTList VTs = DAG.getVTList(Node->getValueType(0), MVT::Other);
3002     SDValue Swap = DAG.getAtomicCmpSwap(
3003         ISD::ATOMIC_CMP_SWAP, dl, cast<AtomicSDNode>(Node)->getMemoryVT(), VTs,
3004         Node->getOperand(0), Node->getOperand(1), Zero, Zero,
3005         cast<AtomicSDNode>(Node)->getMemOperand());
3006     Results.push_back(Swap.getValue(0));
3007     Results.push_back(Swap.getValue(1));
3008     break;
3009   }
3010   case ISD::ATOMIC_STORE: {
3011     // There is no libcall for atomic store; fake it with ATOMIC_SWAP.
3012     SDValue Swap = DAG.getAtomic(ISD::ATOMIC_SWAP, dl,
3013                                  cast<AtomicSDNode>(Node)->getMemoryVT(),
3014                                  Node->getOperand(0),
3015                                  Node->getOperand(1), Node->getOperand(2),
3016                                  cast<AtomicSDNode>(Node)->getMemOperand());
3017     Results.push_back(Swap.getValue(1));
3018     break;
3019   }
3020   case ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS: {
3021     // Expanding an ATOMIC_CMP_SWAP_WITH_SUCCESS produces an ATOMIC_CMP_SWAP and
3022     // splits out the success value as a comparison. Expanding the resulting
3023     // ATOMIC_CMP_SWAP will produce a libcall.
3024     SDVTList VTs = DAG.getVTList(Node->getValueType(0), MVT::Other);
3025     SDValue Res = DAG.getAtomicCmpSwap(
3026         ISD::ATOMIC_CMP_SWAP, dl, cast<AtomicSDNode>(Node)->getMemoryVT(), VTs,
3027         Node->getOperand(0), Node->getOperand(1), Node->getOperand(2),
3028         Node->getOperand(3), cast<MemSDNode>(Node)->getMemOperand());
3029 
3030     SDValue ExtRes = Res;
3031     SDValue LHS = Res;
3032     SDValue RHS = Node->getOperand(1);
3033 
3034     EVT AtomicType = cast<AtomicSDNode>(Node)->getMemoryVT();
3035     EVT OuterType = Node->getValueType(0);
3036     switch (TLI.getExtendForAtomicOps()) {
3037     case ISD::SIGN_EXTEND:
3038       LHS = DAG.getNode(ISD::AssertSext, dl, OuterType, Res,
3039                         DAG.getValueType(AtomicType));
3040       RHS = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl, OuterType,
3041                         Node->getOperand(2), DAG.getValueType(AtomicType));
3042       ExtRes = LHS;
3043       break;
3044     case ISD::ZERO_EXTEND:
3045       LHS = DAG.getNode(ISD::AssertZext, dl, OuterType, Res,
3046                         DAG.getValueType(AtomicType));
3047       RHS = DAG.getZeroExtendInReg(Node->getOperand(2), dl, AtomicType);
3048       ExtRes = LHS;
3049       break;
3050     case ISD::ANY_EXTEND:
3051       LHS = DAG.getZeroExtendInReg(Res, dl, AtomicType);
3052       RHS = DAG.getZeroExtendInReg(Node->getOperand(2), dl, AtomicType);
3053       break;
3054     default:
3055       llvm_unreachable("Invalid atomic op extension");
3056     }
3057 
3058     SDValue Success =
3059         DAG.getSetCC(dl, Node->getValueType(1), LHS, RHS, ISD::SETEQ);
3060 
3061     Results.push_back(ExtRes.getValue(0));
3062     Results.push_back(Success);
3063     Results.push_back(Res.getValue(1));
3064     break;
3065   }
3066   case ISD::DYNAMIC_STACKALLOC:
3067     ExpandDYNAMIC_STACKALLOC(Node, Results);
3068     break;
3069   case ISD::MERGE_VALUES:
3070     for (unsigned i = 0; i < Node->getNumValues(); i++)
3071       Results.push_back(Node->getOperand(i));
3072     break;
3073   case ISD::UNDEF: {
3074     EVT VT = Node->getValueType(0);
3075     if (VT.isInteger())
3076       Results.push_back(DAG.getConstant(0, dl, VT));
3077     else {
3078       assert(VT.isFloatingPoint() && "Unknown value type!");
3079       Results.push_back(DAG.getConstantFP(0, dl, VT));
3080     }
3081     break;
3082   }
3083   case ISD::STRICT_FP_ROUND:
3084     // When strict mode is enforced we can't do expansion because it
3085     // does not honor the "strict" properties. Only libcall is allowed.
3086     if (TLI.isStrictFPEnabled())
3087       break;
3088     // We might as well mutate to FP_ROUND when FP_ROUND operation is legal
3089     // since this operation is more efficient than stack operation.
3090     if (TLI.getStrictFPOperationAction(Node->getOpcode(),
3091                                        Node->getValueType(0))
3092         == TargetLowering::Legal)
3093       break;
3094     // We fall back to use stack operation when the FP_ROUND operation
3095     // isn't available.
3096     if ((Tmp1 = EmitStackConvert(Node->getOperand(1), Node->getValueType(0),
3097                                  Node->getValueType(0), dl,
3098                                  Node->getOperand(0)))) {
3099       ReplaceNode(Node, Tmp1.getNode());
3100       LLVM_DEBUG(dbgs() << "Successfully expanded STRICT_FP_ROUND node\n");
3101       return true;
3102     }
3103     break;
3104   case ISD::FP_ROUND:
3105   case ISD::BITCAST:
3106     if ((Tmp1 = EmitStackConvert(Node->getOperand(0), Node->getValueType(0),
3107                                  Node->getValueType(0), dl)))
3108       Results.push_back(Tmp1);
3109     break;
3110   case ISD::STRICT_FP_EXTEND:
3111     // When strict mode is enforced we can't do expansion because it
3112     // does not honor the "strict" properties. Only libcall is allowed.
3113     if (TLI.isStrictFPEnabled())
3114       break;
3115     // We might as well mutate to FP_EXTEND when FP_EXTEND operation is legal
3116     // since this operation is more efficient than stack operation.
3117     if (TLI.getStrictFPOperationAction(Node->getOpcode(),
3118                                        Node->getValueType(0))
3119         == TargetLowering::Legal)
3120       break;
3121     // We fall back to use stack operation when the FP_EXTEND operation
3122     // isn't available.
3123     if ((Tmp1 = EmitStackConvert(
3124              Node->getOperand(1), Node->getOperand(1).getValueType(),
3125              Node->getValueType(0), dl, Node->getOperand(0)))) {
3126       ReplaceNode(Node, Tmp1.getNode());
3127       LLVM_DEBUG(dbgs() << "Successfully expanded STRICT_FP_EXTEND node\n");
3128       return true;
3129     }
3130     break;
3131   case ISD::FP_EXTEND:
3132     if ((Tmp1 = EmitStackConvert(Node->getOperand(0),
3133                                  Node->getOperand(0).getValueType(),
3134                                  Node->getValueType(0), dl)))
3135       Results.push_back(Tmp1);
3136     break;
3137   case ISD::SIGN_EXTEND_INREG: {
3138     EVT ExtraVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
3139     EVT VT = Node->getValueType(0);
3140 
3141     // An in-register sign-extend of a boolean is a negation:
3142     // 'true' (1) sign-extended is -1.
3143     // 'false' (0) sign-extended is 0.
3144     // However, we must mask the high bits of the source operand because the
3145     // SIGN_EXTEND_INREG does not guarantee that the high bits are already zero.
3146 
3147     // TODO: Do this for vectors too?
3148     if (ExtraVT.getSizeInBits() == 1) {
3149       SDValue One = DAG.getConstant(1, dl, VT);
3150       SDValue And = DAG.getNode(ISD::AND, dl, VT, Node->getOperand(0), One);
3151       SDValue Zero = DAG.getConstant(0, dl, VT);
3152       SDValue Neg = DAG.getNode(ISD::SUB, dl, VT, Zero, And);
3153       Results.push_back(Neg);
3154       break;
3155     }
3156 
3157     // NOTE: we could fall back on load/store here too for targets without
3158     // SRA.  However, it is doubtful that any exist.
3159     EVT ShiftAmountTy = TLI.getShiftAmountTy(VT, DAG.getDataLayout());
3160     unsigned BitsDiff = VT.getScalarSizeInBits() -
3161                         ExtraVT.getScalarSizeInBits();
3162     SDValue ShiftCst = DAG.getConstant(BitsDiff, dl, ShiftAmountTy);
3163     Tmp1 = DAG.getNode(ISD::SHL, dl, Node->getValueType(0),
3164                        Node->getOperand(0), ShiftCst);
3165     Tmp1 = DAG.getNode(ISD::SRA, dl, Node->getValueType(0), Tmp1, ShiftCst);
3166     Results.push_back(Tmp1);
3167     break;
3168   }
3169   case ISD::UINT_TO_FP:
3170   case ISD::STRICT_UINT_TO_FP:
3171     if (TLI.expandUINT_TO_FP(Node, Tmp1, Tmp2, DAG)) {
3172       Results.push_back(Tmp1);
3173       if (Node->isStrictFPOpcode())
3174         Results.push_back(Tmp2);
3175       break;
3176     }
3177     LLVM_FALLTHROUGH;
3178   case ISD::SINT_TO_FP:
3179   case ISD::STRICT_SINT_TO_FP:
3180     if ((Tmp1 = ExpandLegalINT_TO_FP(Node, Tmp2))) {
3181       Results.push_back(Tmp1);
3182       if (Node->isStrictFPOpcode())
3183         Results.push_back(Tmp2);
3184     }
3185     break;
3186   case ISD::FP_TO_SINT:
3187     if (TLI.expandFP_TO_SINT(Node, Tmp1, DAG))
3188       Results.push_back(Tmp1);
3189     break;
3190   case ISD::STRICT_FP_TO_SINT:
3191     if (TLI.expandFP_TO_SINT(Node, Tmp1, DAG)) {
3192       ReplaceNode(Node, Tmp1.getNode());
3193       LLVM_DEBUG(dbgs() << "Successfully expanded STRICT_FP_TO_SINT node\n");
3194       return true;
3195     }
3196     break;
3197   case ISD::FP_TO_UINT:
3198     if (TLI.expandFP_TO_UINT(Node, Tmp1, Tmp2, DAG))
3199       Results.push_back(Tmp1);
3200     break;
3201   case ISD::STRICT_FP_TO_UINT:
3202     if (TLI.expandFP_TO_UINT(Node, Tmp1, Tmp2, DAG)) {
3203       // Relink the chain.
3204       DAG.ReplaceAllUsesOfValueWith(SDValue(Node,1), Tmp2);
3205       // Replace the new UINT result.
3206       ReplaceNodeWithValue(SDValue(Node, 0), Tmp1);
3207       LLVM_DEBUG(dbgs() << "Successfully expanded STRICT_FP_TO_UINT node\n");
3208       return true;
3209     }
3210     break;
3211   case ISD::FP_TO_SINT_SAT:
3212   case ISD::FP_TO_UINT_SAT:
3213     Results.push_back(TLI.expandFP_TO_INT_SAT(Node, DAG));
3214     break;
3215   case ISD::VAARG:
3216     Results.push_back(DAG.expandVAArg(Node));
3217     Results.push_back(Results[0].getValue(1));
3218     break;
3219   case ISD::VACOPY:
3220     Results.push_back(DAG.expandVACopy(Node));
3221     break;
3222   case ISD::EXTRACT_VECTOR_ELT:
3223     if (Node->getOperand(0).getValueType().getVectorNumElements() == 1)
3224       // This must be an access of the only element.  Return it.
3225       Tmp1 = DAG.getNode(ISD::BITCAST, dl, Node->getValueType(0),
3226                          Node->getOperand(0));
3227     else
3228       Tmp1 = ExpandExtractFromVectorThroughStack(SDValue(Node, 0));
3229     Results.push_back(Tmp1);
3230     break;
3231   case ISD::EXTRACT_SUBVECTOR:
3232     Results.push_back(ExpandExtractFromVectorThroughStack(SDValue(Node, 0)));
3233     break;
3234   case ISD::INSERT_SUBVECTOR:
3235     Results.push_back(ExpandInsertToVectorThroughStack(SDValue(Node, 0)));
3236     break;
3237   case ISD::CONCAT_VECTORS:
3238     Results.push_back(ExpandVectorBuildThroughStack(Node));
3239     break;
3240   case ISD::SCALAR_TO_VECTOR:
3241     Results.push_back(ExpandSCALAR_TO_VECTOR(Node));
3242     break;
3243   case ISD::INSERT_VECTOR_ELT:
3244     Results.push_back(ExpandINSERT_VECTOR_ELT(Node->getOperand(0),
3245                                               Node->getOperand(1),
3246                                               Node->getOperand(2), dl));
3247     break;
3248   case ISD::VECTOR_SHUFFLE: {
3249     SmallVector<int, 32> NewMask;
3250     ArrayRef<int> Mask = cast<ShuffleVectorSDNode>(Node)->getMask();
3251 
3252     EVT VT = Node->getValueType(0);
3253     EVT EltVT = VT.getVectorElementType();
3254     SDValue Op0 = Node->getOperand(0);
3255     SDValue Op1 = Node->getOperand(1);
3256     if (!TLI.isTypeLegal(EltVT)) {
3257       EVT NewEltVT = TLI.getTypeToTransformTo(*DAG.getContext(), EltVT);
3258 
3259       // BUILD_VECTOR operands are allowed to be wider than the element type.
3260       // But if NewEltVT is smaller that EltVT the BUILD_VECTOR does not accept
3261       // it.
3262       if (NewEltVT.bitsLT(EltVT)) {
3263         // Convert shuffle node.
3264         // If original node was v4i64 and the new EltVT is i32,
3265         // cast operands to v8i32 and re-build the mask.
3266 
3267         // Calculate new VT, the size of the new VT should be equal to original.
3268         EVT NewVT =
3269             EVT::getVectorVT(*DAG.getContext(), NewEltVT,
3270                              VT.getSizeInBits() / NewEltVT.getSizeInBits());
3271         assert(NewVT.bitsEq(VT));
3272 
3273         // cast operands to new VT
3274         Op0 = DAG.getNode(ISD::BITCAST, dl, NewVT, Op0);
3275         Op1 = DAG.getNode(ISD::BITCAST, dl, NewVT, Op1);
3276 
3277         // Convert the shuffle mask
3278         unsigned int factor =
3279                          NewVT.getVectorNumElements()/VT.getVectorNumElements();
3280 
3281         // EltVT gets smaller
3282         assert(factor > 0);
3283 
3284         for (unsigned i = 0; i < VT.getVectorNumElements(); ++i) {
3285           if (Mask[i] < 0) {
3286             for (unsigned fi = 0; fi < factor; ++fi)
3287               NewMask.push_back(Mask[i]);
3288           }
3289           else {
3290             for (unsigned fi = 0; fi < factor; ++fi)
3291               NewMask.push_back(Mask[i]*factor+fi);
3292           }
3293         }
3294         Mask = NewMask;
3295         VT = NewVT;
3296       }
3297       EltVT = NewEltVT;
3298     }
3299     unsigned NumElems = VT.getVectorNumElements();
3300     SmallVector<SDValue, 16> Ops;
3301     for (unsigned i = 0; i != NumElems; ++i) {
3302       if (Mask[i] < 0) {
3303         Ops.push_back(DAG.getUNDEF(EltVT));
3304         continue;
3305       }
3306       unsigned Idx = Mask[i];
3307       if (Idx < NumElems)
3308         Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT, Op0,
3309                                   DAG.getVectorIdxConstant(Idx, dl)));
3310       else
3311         Ops.push_back(
3312             DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT, Op1,
3313                         DAG.getVectorIdxConstant(Idx - NumElems, dl)));
3314     }
3315 
3316     Tmp1 = DAG.getBuildVector(VT, dl, Ops);
3317     // We may have changed the BUILD_VECTOR type. Cast it back to the Node type.
3318     Tmp1 = DAG.getNode(ISD::BITCAST, dl, Node->getValueType(0), Tmp1);
3319     Results.push_back(Tmp1);
3320     break;
3321   }
3322   case ISD::EXTRACT_ELEMENT: {
3323     EVT OpTy = Node->getOperand(0).getValueType();
3324     if (cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue()) {
3325       // 1 -> Hi
3326       Tmp1 = DAG.getNode(ISD::SRL, dl, OpTy, Node->getOperand(0),
3327                          DAG.getConstant(OpTy.getSizeInBits() / 2, dl,
3328                                          TLI.getShiftAmountTy(
3329                                              Node->getOperand(0).getValueType(),
3330                                              DAG.getDataLayout())));
3331       Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0), Tmp1);
3332     } else {
3333       // 0 -> Lo
3334       Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0),
3335                          Node->getOperand(0));
3336     }
3337     Results.push_back(Tmp1);
3338     break;
3339   }
3340   case ISD::STACKSAVE:
3341     // Expand to CopyFromReg if the target set
3342     // StackPointerRegisterToSaveRestore.
3343     if (Register SP = TLI.getStackPointerRegisterToSaveRestore()) {
3344       Results.push_back(DAG.getCopyFromReg(Node->getOperand(0), dl, SP,
3345                                            Node->getValueType(0)));
3346       Results.push_back(Results[0].getValue(1));
3347     } else {
3348       Results.push_back(DAG.getUNDEF(Node->getValueType(0)));
3349       Results.push_back(Node->getOperand(0));
3350     }
3351     break;
3352   case ISD::STACKRESTORE:
3353     // Expand to CopyToReg if the target set
3354     // StackPointerRegisterToSaveRestore.
3355     if (Register SP = TLI.getStackPointerRegisterToSaveRestore()) {
3356       Results.push_back(DAG.getCopyToReg(Node->getOperand(0), dl, SP,
3357                                          Node->getOperand(1)));
3358     } else {
3359       Results.push_back(Node->getOperand(0));
3360     }
3361     break;
3362   case ISD::GET_DYNAMIC_AREA_OFFSET:
3363     Results.push_back(DAG.getConstant(0, dl, Node->getValueType(0)));
3364     Results.push_back(Results[0].getValue(0));
3365     break;
3366   case ISD::FCOPYSIGN:
3367     Results.push_back(ExpandFCOPYSIGN(Node));
3368     break;
3369   case ISD::FNEG:
3370     Results.push_back(ExpandFNEG(Node));
3371     break;
3372   case ISD::FABS:
3373     Results.push_back(ExpandFABS(Node));
3374     break;
3375   case ISD::SMIN:
3376   case ISD::SMAX:
3377   case ISD::UMIN:
3378   case ISD::UMAX: {
3379     // Expand Y = MAX(A, B) -> Y = (A > B) ? A : B
3380     ISD::CondCode Pred;
3381     switch (Node->getOpcode()) {
3382     default: llvm_unreachable("How did we get here?");
3383     case ISD::SMAX: Pred = ISD::SETGT; break;
3384     case ISD::SMIN: Pred = ISD::SETLT; break;
3385     case ISD::UMAX: Pred = ISD::SETUGT; break;
3386     case ISD::UMIN: Pred = ISD::SETULT; break;
3387     }
3388     Tmp1 = Node->getOperand(0);
3389     Tmp2 = Node->getOperand(1);
3390     Tmp1 = DAG.getSelectCC(dl, Tmp1, Tmp2, Tmp1, Tmp2, Pred);
3391     Results.push_back(Tmp1);
3392     break;
3393   }
3394   case ISD::FMINNUM:
3395   case ISD::FMAXNUM: {
3396     if (SDValue Expanded = TLI.expandFMINNUM_FMAXNUM(Node, DAG))
3397       Results.push_back(Expanded);
3398     break;
3399   }
3400   case ISD::FSIN:
3401   case ISD::FCOS: {
3402     EVT VT = Node->getValueType(0);
3403     // Turn fsin / fcos into ISD::FSINCOS node if there are a pair of fsin /
3404     // fcos which share the same operand and both are used.
3405     if ((TLI.isOperationLegalOrCustom(ISD::FSINCOS, VT) ||
3406          isSinCosLibcallAvailable(Node, TLI))
3407         && useSinCos(Node)) {
3408       SDVTList VTs = DAG.getVTList(VT, VT);
3409       Tmp1 = DAG.getNode(ISD::FSINCOS, dl, VTs, Node->getOperand(0));
3410       if (Node->getOpcode() == ISD::FCOS)
3411         Tmp1 = Tmp1.getValue(1);
3412       Results.push_back(Tmp1);
3413     }
3414     break;
3415   }
3416   case ISD::FMAD:
3417     llvm_unreachable("Illegal fmad should never be formed");
3418 
3419   case ISD::FP16_TO_FP:
3420     if (Node->getValueType(0) != MVT::f32) {
3421       // We can extend to types bigger than f32 in two steps without changing
3422       // the result. Since "f16 -> f32" is much more commonly available, give
3423       // CodeGen the option of emitting that before resorting to a libcall.
3424       SDValue Res =
3425           DAG.getNode(ISD::FP16_TO_FP, dl, MVT::f32, Node->getOperand(0));
3426       Results.push_back(
3427           DAG.getNode(ISD::FP_EXTEND, dl, Node->getValueType(0), Res));
3428     }
3429     break;
3430   case ISD::STRICT_FP16_TO_FP:
3431     if (Node->getValueType(0) != MVT::f32) {
3432       // We can extend to types bigger than f32 in two steps without changing
3433       // the result. Since "f16 -> f32" is much more commonly available, give
3434       // CodeGen the option of emitting that before resorting to a libcall.
3435       SDValue Res =
3436           DAG.getNode(ISD::STRICT_FP16_TO_FP, dl, {MVT::f32, MVT::Other},
3437                       {Node->getOperand(0), Node->getOperand(1)});
3438       Res = DAG.getNode(ISD::STRICT_FP_EXTEND, dl,
3439                         {Node->getValueType(0), MVT::Other},
3440                         {Res.getValue(1), Res});
3441       Results.push_back(Res);
3442       Results.push_back(Res.getValue(1));
3443     }
3444     break;
3445   case ISD::FP_TO_FP16:
3446     LLVM_DEBUG(dbgs() << "Legalizing FP_TO_FP16\n");
3447     if (!TLI.useSoftFloat() && TM.Options.UnsafeFPMath) {
3448       SDValue Op = Node->getOperand(0);
3449       MVT SVT = Op.getSimpleValueType();
3450       if ((SVT == MVT::f64 || SVT == MVT::f80) &&
3451           TLI.isOperationLegalOrCustom(ISD::FP_TO_FP16, MVT::f32)) {
3452         // Under fastmath, we can expand this node into a fround followed by
3453         // a float-half conversion.
3454         SDValue FloatVal = DAG.getNode(ISD::FP_ROUND, dl, MVT::f32, Op,
3455                                        DAG.getIntPtrConstant(0, dl));
3456         Results.push_back(
3457             DAG.getNode(ISD::FP_TO_FP16, dl, Node->getValueType(0), FloatVal));
3458       }
3459     }
3460     break;
3461   case ISD::ConstantFP: {
3462     ConstantFPSDNode *CFP = cast<ConstantFPSDNode>(Node);
3463     // Check to see if this FP immediate is already legal.
3464     // If this is a legal constant, turn it into a TargetConstantFP node.
3465     if (!TLI.isFPImmLegal(CFP->getValueAPF(), Node->getValueType(0),
3466                           DAG.shouldOptForSize()))
3467       Results.push_back(ExpandConstantFP(CFP, true));
3468     break;
3469   }
3470   case ISD::Constant: {
3471     ConstantSDNode *CP = cast<ConstantSDNode>(Node);
3472     Results.push_back(ExpandConstant(CP));
3473     break;
3474   }
3475   case ISD::FSUB: {
3476     EVT VT = Node->getValueType(0);
3477     if (TLI.isOperationLegalOrCustom(ISD::FADD, VT) &&
3478         TLI.isOperationLegalOrCustom(ISD::FNEG, VT)) {
3479       const SDNodeFlags Flags = Node->getFlags();
3480       Tmp1 = DAG.getNode(ISD::FNEG, dl, VT, Node->getOperand(1));
3481       Tmp1 = DAG.getNode(ISD::FADD, dl, VT, Node->getOperand(0), Tmp1, Flags);
3482       Results.push_back(Tmp1);
3483     }
3484     break;
3485   }
3486   case ISD::SUB: {
3487     EVT VT = Node->getValueType(0);
3488     assert(TLI.isOperationLegalOrCustom(ISD::ADD, VT) &&
3489            TLI.isOperationLegalOrCustom(ISD::XOR, VT) &&
3490            "Don't know how to expand this subtraction!");
3491     Tmp1 = DAG.getNode(ISD::XOR, dl, VT, Node->getOperand(1),
3492                DAG.getConstant(APInt::getAllOnesValue(VT.getSizeInBits()), dl,
3493                                VT));
3494     Tmp1 = DAG.getNode(ISD::ADD, dl, VT, Tmp1, DAG.getConstant(1, dl, VT));
3495     Results.push_back(DAG.getNode(ISD::ADD, dl, VT, Node->getOperand(0), Tmp1));
3496     break;
3497   }
3498   case ISD::UREM:
3499   case ISD::SREM:
3500     if (TLI.expandREM(Node, Tmp1, DAG))
3501       Results.push_back(Tmp1);
3502     break;
3503   case ISD::UDIV:
3504   case ISD::SDIV: {
3505     bool isSigned = Node->getOpcode() == ISD::SDIV;
3506     unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
3507     EVT VT = Node->getValueType(0);
3508     if (TLI.isOperationLegalOrCustom(DivRemOpc, VT)) {
3509       SDVTList VTs = DAG.getVTList(VT, VT);
3510       Tmp1 = DAG.getNode(DivRemOpc, dl, VTs, Node->getOperand(0),
3511                          Node->getOperand(1));
3512       Results.push_back(Tmp1);
3513     }
3514     break;
3515   }
3516   case ISD::MULHU:
3517   case ISD::MULHS: {
3518     unsigned ExpandOpcode =
3519         Node->getOpcode() == ISD::MULHU ? ISD::UMUL_LOHI : ISD::SMUL_LOHI;
3520     EVT VT = Node->getValueType(0);
3521     SDVTList VTs = DAG.getVTList(VT, VT);
3522 
3523     Tmp1 = DAG.getNode(ExpandOpcode, dl, VTs, Node->getOperand(0),
3524                        Node->getOperand(1));
3525     Results.push_back(Tmp1.getValue(1));
3526     break;
3527   }
3528   case ISD::UMUL_LOHI:
3529   case ISD::SMUL_LOHI: {
3530     SDValue LHS = Node->getOperand(0);
3531     SDValue RHS = Node->getOperand(1);
3532     MVT VT = LHS.getSimpleValueType();
3533     unsigned MULHOpcode =
3534         Node->getOpcode() == ISD::UMUL_LOHI ? ISD::MULHU : ISD::MULHS;
3535 
3536     if (TLI.isOperationLegalOrCustom(MULHOpcode, VT)) {
3537       Results.push_back(DAG.getNode(ISD::MUL, dl, VT, LHS, RHS));
3538       Results.push_back(DAG.getNode(MULHOpcode, dl, VT, LHS, RHS));
3539       break;
3540     }
3541 
3542     SmallVector<SDValue, 4> Halves;
3543     EVT HalfType = EVT(VT).getHalfSizedIntegerVT(*DAG.getContext());
3544     assert(TLI.isTypeLegal(HalfType));
3545     if (TLI.expandMUL_LOHI(Node->getOpcode(), VT, dl, LHS, RHS, Halves,
3546                            HalfType, DAG,
3547                            TargetLowering::MulExpansionKind::Always)) {
3548       for (unsigned i = 0; i < 2; ++i) {
3549         SDValue Lo = DAG.getNode(ISD::ZERO_EXTEND, dl, VT, Halves[2 * i]);
3550         SDValue Hi = DAG.getNode(ISD::ANY_EXTEND, dl, VT, Halves[2 * i + 1]);
3551         SDValue Shift = DAG.getConstant(
3552             HalfType.getScalarSizeInBits(), dl,
3553             TLI.getShiftAmountTy(HalfType, DAG.getDataLayout()));
3554         Hi = DAG.getNode(ISD::SHL, dl, VT, Hi, Shift);
3555         Results.push_back(DAG.getNode(ISD::OR, dl, VT, Lo, Hi));
3556       }
3557       break;
3558     }
3559     break;
3560   }
3561   case ISD::MUL: {
3562     EVT VT = Node->getValueType(0);
3563     SDVTList VTs = DAG.getVTList(VT, VT);
3564     // See if multiply or divide can be lowered using two-result operations.
3565     // We just need the low half of the multiply; try both the signed
3566     // and unsigned forms. If the target supports both SMUL_LOHI and
3567     // UMUL_LOHI, form a preference by checking which forms of plain
3568     // MULH it supports.
3569     bool HasSMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::SMUL_LOHI, VT);
3570     bool HasUMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::UMUL_LOHI, VT);
3571     bool HasMULHS = TLI.isOperationLegalOrCustom(ISD::MULHS, VT);
3572     bool HasMULHU = TLI.isOperationLegalOrCustom(ISD::MULHU, VT);
3573     unsigned OpToUse = 0;
3574     if (HasSMUL_LOHI && !HasMULHS) {
3575       OpToUse = ISD::SMUL_LOHI;
3576     } else if (HasUMUL_LOHI && !HasMULHU) {
3577       OpToUse = ISD::UMUL_LOHI;
3578     } else if (HasSMUL_LOHI) {
3579       OpToUse = ISD::SMUL_LOHI;
3580     } else if (HasUMUL_LOHI) {
3581       OpToUse = ISD::UMUL_LOHI;
3582     }
3583     if (OpToUse) {
3584       Results.push_back(DAG.getNode(OpToUse, dl, VTs, Node->getOperand(0),
3585                                     Node->getOperand(1)));
3586       break;
3587     }
3588 
3589     SDValue Lo, Hi;
3590     EVT HalfType = VT.getHalfSizedIntegerVT(*DAG.getContext());
3591     if (TLI.isOperationLegalOrCustom(ISD::ZERO_EXTEND, VT) &&
3592         TLI.isOperationLegalOrCustom(ISD::ANY_EXTEND, VT) &&
3593         TLI.isOperationLegalOrCustom(ISD::SHL, VT) &&
3594         TLI.isOperationLegalOrCustom(ISD::OR, VT) &&
3595         TLI.expandMUL(Node, Lo, Hi, HalfType, DAG,
3596                       TargetLowering::MulExpansionKind::OnlyLegalOrCustom)) {
3597       Lo = DAG.getNode(ISD::ZERO_EXTEND, dl, VT, Lo);
3598       Hi = DAG.getNode(ISD::ANY_EXTEND, dl, VT, Hi);
3599       SDValue Shift =
3600           DAG.getConstant(HalfType.getSizeInBits(), dl,
3601                           TLI.getShiftAmountTy(HalfType, DAG.getDataLayout()));
3602       Hi = DAG.getNode(ISD::SHL, dl, VT, Hi, Shift);
3603       Results.push_back(DAG.getNode(ISD::OR, dl, VT, Lo, Hi));
3604     }
3605     break;
3606   }
3607   case ISD::FSHL:
3608   case ISD::FSHR:
3609     if (TLI.expandFunnelShift(Node, Tmp1, DAG))
3610       Results.push_back(Tmp1);
3611     break;
3612   case ISD::ROTL:
3613   case ISD::ROTR:
3614     if (TLI.expandROT(Node, true /*AllowVectorOps*/, Tmp1, DAG))
3615       Results.push_back(Tmp1);
3616     break;
3617   case ISD::SADDSAT:
3618   case ISD::UADDSAT:
3619   case ISD::SSUBSAT:
3620   case ISD::USUBSAT:
3621     Results.push_back(TLI.expandAddSubSat(Node, DAG));
3622     break;
3623   case ISD::SSHLSAT:
3624   case ISD::USHLSAT:
3625     Results.push_back(TLI.expandShlSat(Node, DAG));
3626     break;
3627   case ISD::SMULFIX:
3628   case ISD::SMULFIXSAT:
3629   case ISD::UMULFIX:
3630   case ISD::UMULFIXSAT:
3631     Results.push_back(TLI.expandFixedPointMul(Node, DAG));
3632     break;
3633   case ISD::SDIVFIX:
3634   case ISD::SDIVFIXSAT:
3635   case ISD::UDIVFIX:
3636   case ISD::UDIVFIXSAT:
3637     if (SDValue V = TLI.expandFixedPointDiv(Node->getOpcode(), SDLoc(Node),
3638                                             Node->getOperand(0),
3639                                             Node->getOperand(1),
3640                                             Node->getConstantOperandVal(2),
3641                                             DAG)) {
3642       Results.push_back(V);
3643       break;
3644     }
3645     // FIXME: We might want to retry here with a wider type if we fail, if that
3646     // type is legal.
3647     // FIXME: Technically, so long as we only have sdivfixes where BW+Scale is
3648     // <= 128 (which is the case for all of the default Embedded-C types),
3649     // we will only get here with types and scales that we could always expand
3650     // if we were allowed to generate libcalls to division functions of illegal
3651     // type. But we cannot do that.
3652     llvm_unreachable("Cannot expand DIVFIX!");
3653   case ISD::ADDCARRY:
3654   case ISD::SUBCARRY: {
3655     SDValue LHS = Node->getOperand(0);
3656     SDValue RHS = Node->getOperand(1);
3657     SDValue Carry = Node->getOperand(2);
3658 
3659     bool IsAdd = Node->getOpcode() == ISD::ADDCARRY;
3660 
3661     // Initial add of the 2 operands.
3662     unsigned Op = IsAdd ? ISD::ADD : ISD::SUB;
3663     EVT VT = LHS.getValueType();
3664     SDValue Sum = DAG.getNode(Op, dl, VT, LHS, RHS);
3665 
3666     // Initial check for overflow.
3667     EVT CarryType = Node->getValueType(1);
3668     EVT SetCCType = getSetCCResultType(Node->getValueType(0));
3669     ISD::CondCode CC = IsAdd ? ISD::SETULT : ISD::SETUGT;
3670     SDValue Overflow = DAG.getSetCC(dl, SetCCType, Sum, LHS, CC);
3671 
3672     // Add of the sum and the carry.
3673     SDValue One = DAG.getConstant(1, dl, VT);
3674     SDValue CarryExt =
3675         DAG.getNode(ISD::AND, dl, VT, DAG.getZExtOrTrunc(Carry, dl, VT), One);
3676     SDValue Sum2 = DAG.getNode(Op, dl, VT, Sum, CarryExt);
3677 
3678     // Second check for overflow. If we are adding, we can only overflow if the
3679     // initial sum is all 1s ang the carry is set, resulting in a new sum of 0.
3680     // If we are subtracting, we can only overflow if the initial sum is 0 and
3681     // the carry is set, resulting in a new sum of all 1s.
3682     SDValue Zero = DAG.getConstant(0, dl, VT);
3683     SDValue Overflow2 =
3684         IsAdd ? DAG.getSetCC(dl, SetCCType, Sum2, Zero, ISD::SETEQ)
3685               : DAG.getSetCC(dl, SetCCType, Sum, Zero, ISD::SETEQ);
3686     Overflow2 = DAG.getNode(ISD::AND, dl, SetCCType, Overflow2,
3687                             DAG.getZExtOrTrunc(Carry, dl, SetCCType));
3688 
3689     SDValue ResultCarry =
3690         DAG.getNode(ISD::OR, dl, SetCCType, Overflow, Overflow2);
3691 
3692     Results.push_back(Sum2);
3693     Results.push_back(DAG.getBoolExtOrTrunc(ResultCarry, dl, CarryType, VT));
3694     break;
3695   }
3696   case ISD::SADDO:
3697   case ISD::SSUBO: {
3698     SDValue Result, Overflow;
3699     TLI.expandSADDSUBO(Node, Result, Overflow, DAG);
3700     Results.push_back(Result);
3701     Results.push_back(Overflow);
3702     break;
3703   }
3704   case ISD::UADDO:
3705   case ISD::USUBO: {
3706     SDValue Result, Overflow;
3707     TLI.expandUADDSUBO(Node, Result, Overflow, DAG);
3708     Results.push_back(Result);
3709     Results.push_back(Overflow);
3710     break;
3711   }
3712   case ISD::UMULO:
3713   case ISD::SMULO: {
3714     SDValue Result, Overflow;
3715     if (TLI.expandMULO(Node, Result, Overflow, DAG)) {
3716       Results.push_back(Result);
3717       Results.push_back(Overflow);
3718     }
3719     break;
3720   }
3721   case ISD::BUILD_PAIR: {
3722     EVT PairTy = Node->getValueType(0);
3723     Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, PairTy, Node->getOperand(0));
3724     Tmp2 = DAG.getNode(ISD::ANY_EXTEND, dl, PairTy, Node->getOperand(1));
3725     Tmp2 = DAG.getNode(
3726         ISD::SHL, dl, PairTy, Tmp2,
3727         DAG.getConstant(PairTy.getSizeInBits() / 2, dl,
3728                         TLI.getShiftAmountTy(PairTy, DAG.getDataLayout())));
3729     Results.push_back(DAG.getNode(ISD::OR, dl, PairTy, Tmp1, Tmp2));
3730     break;
3731   }
3732   case ISD::SELECT:
3733     Tmp1 = Node->getOperand(0);
3734     Tmp2 = Node->getOperand(1);
3735     Tmp3 = Node->getOperand(2);
3736     if (Tmp1.getOpcode() == ISD::SETCC) {
3737       Tmp1 = DAG.getSelectCC(dl, Tmp1.getOperand(0), Tmp1.getOperand(1),
3738                              Tmp2, Tmp3,
3739                              cast<CondCodeSDNode>(Tmp1.getOperand(2))->get());
3740     } else {
3741       Tmp1 = DAG.getSelectCC(dl, Tmp1,
3742                              DAG.getConstant(0, dl, Tmp1.getValueType()),
3743                              Tmp2, Tmp3, ISD::SETNE);
3744     }
3745     Tmp1->setFlags(Node->getFlags());
3746     Results.push_back(Tmp1);
3747     break;
3748   case ISD::BR_JT: {
3749     SDValue Chain = Node->getOperand(0);
3750     SDValue Table = Node->getOperand(1);
3751     SDValue Index = Node->getOperand(2);
3752 
3753     const DataLayout &TD = DAG.getDataLayout();
3754     EVT PTy = TLI.getPointerTy(TD);
3755 
3756     unsigned EntrySize =
3757       DAG.getMachineFunction().getJumpTableInfo()->getEntrySize(TD);
3758 
3759     // For power-of-two jumptable entry sizes convert multiplication to a shift.
3760     // This transformation needs to be done here since otherwise the MIPS
3761     // backend will end up emitting a three instruction multiply sequence
3762     // instead of a single shift and MSP430 will call a runtime function.
3763     if (llvm::isPowerOf2_32(EntrySize))
3764       Index = DAG.getNode(
3765           ISD::SHL, dl, Index.getValueType(), Index,
3766           DAG.getConstant(llvm::Log2_32(EntrySize), dl, Index.getValueType()));
3767     else
3768       Index = DAG.getNode(ISD::MUL, dl, Index.getValueType(), Index,
3769                           DAG.getConstant(EntrySize, dl, Index.getValueType()));
3770     SDValue Addr = DAG.getNode(ISD::ADD, dl, Index.getValueType(),
3771                                Index, Table);
3772 
3773     EVT MemVT = EVT::getIntegerVT(*DAG.getContext(), EntrySize * 8);
3774     SDValue LD = DAG.getExtLoad(
3775         ISD::SEXTLOAD, dl, PTy, Chain, Addr,
3776         MachinePointerInfo::getJumpTable(DAG.getMachineFunction()), MemVT);
3777     Addr = LD;
3778     if (TLI.isJumpTableRelative()) {
3779       // For PIC, the sequence is:
3780       // BRIND(load(Jumptable + index) + RelocBase)
3781       // RelocBase can be JumpTable, GOT or some sort of global base.
3782       Addr = DAG.getNode(ISD::ADD, dl, PTy, Addr,
3783                           TLI.getPICJumpTableRelocBase(Table, DAG));
3784     }
3785 
3786     Tmp1 = TLI.expandIndirectJTBranch(dl, LD.getValue(1), Addr, DAG);
3787     Results.push_back(Tmp1);
3788     break;
3789   }
3790   case ISD::BRCOND:
3791     // Expand brcond's setcc into its constituent parts and create a BR_CC
3792     // Node.
3793     Tmp1 = Node->getOperand(0);
3794     Tmp2 = Node->getOperand(1);
3795     if (Tmp2.getOpcode() == ISD::SETCC) {
3796       Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other,
3797                          Tmp1, Tmp2.getOperand(2),
3798                          Tmp2.getOperand(0), Tmp2.getOperand(1),
3799                          Node->getOperand(2));
3800     } else {
3801       // We test only the i1 bit.  Skip the AND if UNDEF or another AND.
3802       if (Tmp2.isUndef() ||
3803           (Tmp2.getOpcode() == ISD::AND &&
3804            isa<ConstantSDNode>(Tmp2.getOperand(1)) &&
3805            cast<ConstantSDNode>(Tmp2.getOperand(1))->getZExtValue() == 1))
3806         Tmp3 = Tmp2;
3807       else
3808         Tmp3 = DAG.getNode(ISD::AND, dl, Tmp2.getValueType(), Tmp2,
3809                            DAG.getConstant(1, dl, Tmp2.getValueType()));
3810       Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other, Tmp1,
3811                          DAG.getCondCode(ISD::SETNE), Tmp3,
3812                          DAG.getConstant(0, dl, Tmp3.getValueType()),
3813                          Node->getOperand(2));
3814     }
3815     Results.push_back(Tmp1);
3816     break;
3817   case ISD::SETCC:
3818   case ISD::STRICT_FSETCC:
3819   case ISD::STRICT_FSETCCS: {
3820     bool IsStrict = Node->getOpcode() != ISD::SETCC;
3821     bool IsSignaling = Node->getOpcode() == ISD::STRICT_FSETCCS;
3822     SDValue Chain = IsStrict ? Node->getOperand(0) : SDValue();
3823     unsigned Offset = IsStrict ? 1 : 0;
3824     Tmp1 = Node->getOperand(0 + Offset);
3825     Tmp2 = Node->getOperand(1 + Offset);
3826     Tmp3 = Node->getOperand(2 + Offset);
3827     bool Legalized =
3828         LegalizeSetCCCondCode(Node->getValueType(0), Tmp1, Tmp2, Tmp3,
3829                               NeedInvert, dl, Chain, IsSignaling);
3830 
3831     if (Legalized) {
3832       // If we expanded the SETCC by swapping LHS and RHS, or by inverting the
3833       // condition code, create a new SETCC node.
3834       if (Tmp3.getNode())
3835         Tmp1 = DAG.getNode(ISD::SETCC, dl, Node->getValueType(0),
3836                            Tmp1, Tmp2, Tmp3, Node->getFlags());
3837 
3838       // If we expanded the SETCC by inverting the condition code, then wrap
3839       // the existing SETCC in a NOT to restore the intended condition.
3840       if (NeedInvert)
3841         Tmp1 = DAG.getLogicalNOT(dl, Tmp1, Tmp1->getValueType(0));
3842 
3843       Results.push_back(Tmp1);
3844       if (IsStrict)
3845         Results.push_back(Chain);
3846 
3847       break;
3848     }
3849 
3850     // FIXME: It seems Legalized is false iff CCCode is Legal. I don't
3851     // understand if this code is useful for strict nodes.
3852     assert(!IsStrict && "Don't know how to expand for strict nodes.");
3853 
3854     // Otherwise, SETCC for the given comparison type must be completely
3855     // illegal; expand it into a SELECT_CC.
3856     EVT VT = Node->getValueType(0);
3857     int TrueValue;
3858     switch (TLI.getBooleanContents(Tmp1.getValueType())) {
3859     case TargetLowering::ZeroOrOneBooleanContent:
3860     case TargetLowering::UndefinedBooleanContent:
3861       TrueValue = 1;
3862       break;
3863     case TargetLowering::ZeroOrNegativeOneBooleanContent:
3864       TrueValue = -1;
3865       break;
3866     }
3867     Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, VT, Tmp1, Tmp2,
3868                        DAG.getConstant(TrueValue, dl, VT),
3869                        DAG.getConstant(0, dl, VT),
3870                        Tmp3);
3871     Tmp1->setFlags(Node->getFlags());
3872     Results.push_back(Tmp1);
3873     break;
3874   }
3875   case ISD::SELECT_CC: {
3876     // TODO: need to add STRICT_SELECT_CC and STRICT_SELECT_CCS
3877     Tmp1 = Node->getOperand(0);   // LHS
3878     Tmp2 = Node->getOperand(1);   // RHS
3879     Tmp3 = Node->getOperand(2);   // True
3880     Tmp4 = Node->getOperand(3);   // False
3881     EVT VT = Node->getValueType(0);
3882     SDValue Chain;
3883     SDValue CC = Node->getOperand(4);
3884     ISD::CondCode CCOp = cast<CondCodeSDNode>(CC)->get();
3885 
3886     if (TLI.isCondCodeLegalOrCustom(CCOp, Tmp1.getSimpleValueType())) {
3887       // If the condition code is legal, then we need to expand this
3888       // node using SETCC and SELECT.
3889       EVT CmpVT = Tmp1.getValueType();
3890       assert(!TLI.isOperationExpand(ISD::SELECT, VT) &&
3891              "Cannot expand ISD::SELECT_CC when ISD::SELECT also needs to be "
3892              "expanded.");
3893       EVT CCVT = getSetCCResultType(CmpVT);
3894       SDValue Cond = DAG.getNode(ISD::SETCC, dl, CCVT, Tmp1, Tmp2, CC, Node->getFlags());
3895       Results.push_back(DAG.getSelect(dl, VT, Cond, Tmp3, Tmp4));
3896       break;
3897     }
3898 
3899     // SELECT_CC is legal, so the condition code must not be.
3900     bool Legalized = false;
3901     // Try to legalize by inverting the condition.  This is for targets that
3902     // might support an ordered version of a condition, but not the unordered
3903     // version (or vice versa).
3904     ISD::CondCode InvCC = ISD::getSetCCInverse(CCOp, Tmp1.getValueType());
3905     if (TLI.isCondCodeLegalOrCustom(InvCC, Tmp1.getSimpleValueType())) {
3906       // Use the new condition code and swap true and false
3907       Legalized = true;
3908       Tmp1 = DAG.getSelectCC(dl, Tmp1, Tmp2, Tmp4, Tmp3, InvCC);
3909       Tmp1->setFlags(Node->getFlags());
3910     } else {
3911       // If The inverse is not legal, then try to swap the arguments using
3912       // the inverse condition code.
3913       ISD::CondCode SwapInvCC = ISD::getSetCCSwappedOperands(InvCC);
3914       if (TLI.isCondCodeLegalOrCustom(SwapInvCC, Tmp1.getSimpleValueType())) {
3915         // The swapped inverse condition is legal, so swap true and false,
3916         // lhs and rhs.
3917         Legalized = true;
3918         Tmp1 = DAG.getSelectCC(dl, Tmp2, Tmp1, Tmp4, Tmp3, SwapInvCC);
3919         Tmp1->setFlags(Node->getFlags());
3920       }
3921     }
3922 
3923     if (!Legalized) {
3924       Legalized = LegalizeSetCCCondCode(getSetCCResultType(Tmp1.getValueType()),
3925                                         Tmp1, Tmp2, CC, NeedInvert, dl, Chain);
3926 
3927       assert(Legalized && "Can't legalize SELECT_CC with legal condition!");
3928 
3929       // If we expanded the SETCC by inverting the condition code, then swap
3930       // the True/False operands to match.
3931       if (NeedInvert)
3932         std::swap(Tmp3, Tmp4);
3933 
3934       // If we expanded the SETCC by swapping LHS and RHS, or by inverting the
3935       // condition code, create a new SELECT_CC node.
3936       if (CC.getNode()) {
3937         Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, Node->getValueType(0),
3938                            Tmp1, Tmp2, Tmp3, Tmp4, CC);
3939       } else {
3940         Tmp2 = DAG.getConstant(0, dl, Tmp1.getValueType());
3941         CC = DAG.getCondCode(ISD::SETNE);
3942         Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, Node->getValueType(0), Tmp1,
3943                            Tmp2, Tmp3, Tmp4, CC);
3944       }
3945       Tmp1->setFlags(Node->getFlags());
3946     }
3947     Results.push_back(Tmp1);
3948     break;
3949   }
3950   case ISD::BR_CC: {
3951     // TODO: need to add STRICT_BR_CC and STRICT_BR_CCS
3952     SDValue Chain;
3953     Tmp1 = Node->getOperand(0);              // Chain
3954     Tmp2 = Node->getOperand(2);              // LHS
3955     Tmp3 = Node->getOperand(3);              // RHS
3956     Tmp4 = Node->getOperand(1);              // CC
3957 
3958     bool Legalized =
3959         LegalizeSetCCCondCode(getSetCCResultType(Tmp2.getValueType()), Tmp2,
3960                               Tmp3, Tmp4, NeedInvert, dl, Chain);
3961     (void)Legalized;
3962     assert(Legalized && "Can't legalize BR_CC with legal condition!");
3963 
3964     assert(!NeedInvert && "Don't know how to invert BR_CC!");
3965 
3966     // If we expanded the SETCC by swapping LHS and RHS, create a new BR_CC
3967     // node.
3968     if (Tmp4.getNode()) {
3969       Tmp1 = DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0), Tmp1,
3970                          Tmp4, Tmp2, Tmp3, Node->getOperand(4));
3971     } else {
3972       Tmp3 = DAG.getConstant(0, dl, Tmp2.getValueType());
3973       Tmp4 = DAG.getCondCode(ISD::SETNE);
3974       Tmp1 = DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0), Tmp1, Tmp4,
3975                          Tmp2, Tmp3, Node->getOperand(4));
3976     }
3977     Results.push_back(Tmp1);
3978     break;
3979   }
3980   case ISD::BUILD_VECTOR:
3981     Results.push_back(ExpandBUILD_VECTOR(Node));
3982     break;
3983   case ISD::SPLAT_VECTOR:
3984     Results.push_back(ExpandSPLAT_VECTOR(Node));
3985     break;
3986   case ISD::SRA:
3987   case ISD::SRL:
3988   case ISD::SHL: {
3989     // Scalarize vector SRA/SRL/SHL.
3990     EVT VT = Node->getValueType(0);
3991     assert(VT.isVector() && "Unable to legalize non-vector shift");
3992     assert(TLI.isTypeLegal(VT.getScalarType())&& "Element type must be legal");
3993     unsigned NumElem = VT.getVectorNumElements();
3994 
3995     SmallVector<SDValue, 8> Scalars;
3996     for (unsigned Idx = 0; Idx < NumElem; Idx++) {
3997       SDValue Ex =
3998           DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, VT.getScalarType(),
3999                       Node->getOperand(0), DAG.getVectorIdxConstant(Idx, dl));
4000       SDValue Sh =
4001           DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, VT.getScalarType(),
4002                       Node->getOperand(1), DAG.getVectorIdxConstant(Idx, dl));
4003       Scalars.push_back(DAG.getNode(Node->getOpcode(), dl,
4004                                     VT.getScalarType(), Ex, Sh));
4005     }
4006 
4007     SDValue Result = DAG.getBuildVector(Node->getValueType(0), dl, Scalars);
4008     Results.push_back(Result);
4009     break;
4010   }
4011   case ISD::VECREDUCE_FADD:
4012   case ISD::VECREDUCE_FMUL:
4013   case ISD::VECREDUCE_ADD:
4014   case ISD::VECREDUCE_MUL:
4015   case ISD::VECREDUCE_AND:
4016   case ISD::VECREDUCE_OR:
4017   case ISD::VECREDUCE_XOR:
4018   case ISD::VECREDUCE_SMAX:
4019   case ISD::VECREDUCE_SMIN:
4020   case ISD::VECREDUCE_UMAX:
4021   case ISD::VECREDUCE_UMIN:
4022   case ISD::VECREDUCE_FMAX:
4023   case ISD::VECREDUCE_FMIN:
4024     Results.push_back(TLI.expandVecReduce(Node, DAG));
4025     break;
4026   case ISD::GLOBAL_OFFSET_TABLE:
4027   case ISD::GlobalAddress:
4028   case ISD::GlobalTLSAddress:
4029   case ISD::ExternalSymbol:
4030   case ISD::ConstantPool:
4031   case ISD::JumpTable:
4032   case ISD::INTRINSIC_W_CHAIN:
4033   case ISD::INTRINSIC_WO_CHAIN:
4034   case ISD::INTRINSIC_VOID:
4035     // FIXME: Custom lowering for these operations shouldn't return null!
4036     // Return true so that we don't call ConvertNodeToLibcall which also won't
4037     // do anything.
4038     return true;
4039   }
4040 
4041   if (!TLI.isStrictFPEnabled() && Results.empty() && Node->isStrictFPOpcode()) {
4042     // FIXME: We were asked to expand a strict floating-point operation,
4043     // but there is currently no expansion implemented that would preserve
4044     // the "strict" properties.  For now, we just fall back to the non-strict
4045     // version if that is legal on the target.  The actual mutation of the
4046     // operation will happen in SelectionDAGISel::DoInstructionSelection.
4047     switch (Node->getOpcode()) {
4048     default:
4049       if (TLI.getStrictFPOperationAction(Node->getOpcode(),
4050                                          Node->getValueType(0))
4051           == TargetLowering::Legal)
4052         return true;
4053       break;
4054     case ISD::STRICT_FSUB: {
4055       if (TLI.getStrictFPOperationAction(
4056               ISD::STRICT_FSUB, Node->getValueType(0)) == TargetLowering::Legal)
4057         return true;
4058       if (TLI.getStrictFPOperationAction(
4059               ISD::STRICT_FADD, Node->getValueType(0)) != TargetLowering::Legal)
4060         break;
4061 
4062       EVT VT = Node->getValueType(0);
4063       const SDNodeFlags Flags = Node->getFlags();
4064       SDValue Neg = DAG.getNode(ISD::FNEG, dl, VT, Node->getOperand(2), Flags);
4065       SDValue Fadd = DAG.getNode(ISD::STRICT_FADD, dl, Node->getVTList(),
4066                                  {Node->getOperand(0), Node->getOperand(1), Neg},
4067                          Flags);
4068 
4069       Results.push_back(Fadd);
4070       Results.push_back(Fadd.getValue(1));
4071       break;
4072     }
4073     case ISD::STRICT_SINT_TO_FP:
4074     case ISD::STRICT_UINT_TO_FP:
4075     case ISD::STRICT_LRINT:
4076     case ISD::STRICT_LLRINT:
4077     case ISD::STRICT_LROUND:
4078     case ISD::STRICT_LLROUND:
4079       // These are registered by the operand type instead of the value
4080       // type. Reflect that here.
4081       if (TLI.getStrictFPOperationAction(Node->getOpcode(),
4082                                          Node->getOperand(1).getValueType())
4083           == TargetLowering::Legal)
4084         return true;
4085       break;
4086     }
4087   }
4088 
4089   // Replace the original node with the legalized result.
4090   if (Results.empty()) {
4091     LLVM_DEBUG(dbgs() << "Cannot expand node\n");
4092     return false;
4093   }
4094 
4095   LLVM_DEBUG(dbgs() << "Successfully expanded node\n");
4096   ReplaceNode(Node, Results.data());
4097   return true;
4098 }
4099 
4100 void SelectionDAGLegalize::ConvertNodeToLibcall(SDNode *Node) {
4101   LLVM_DEBUG(dbgs() << "Trying to convert node to libcall\n");
4102   SmallVector<SDValue, 8> Results;
4103   SDLoc dl(Node);
4104   // FIXME: Check flags on the node to see if we can use a finite call.
4105   unsigned Opc = Node->getOpcode();
4106   switch (Opc) {
4107   case ISD::ATOMIC_FENCE: {
4108     // If the target didn't lower this, lower it to '__sync_synchronize()' call
4109     // FIXME: handle "fence singlethread" more efficiently.
4110     TargetLowering::ArgListTy Args;
4111 
4112     TargetLowering::CallLoweringInfo CLI(DAG);
4113     CLI.setDebugLoc(dl)
4114         .setChain(Node->getOperand(0))
4115         .setLibCallee(
4116             CallingConv::C, Type::getVoidTy(*DAG.getContext()),
4117             DAG.getExternalSymbol("__sync_synchronize",
4118                                   TLI.getPointerTy(DAG.getDataLayout())),
4119             std::move(Args));
4120 
4121     std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
4122 
4123     Results.push_back(CallResult.second);
4124     break;
4125   }
4126   // By default, atomic intrinsics are marked Legal and lowered. Targets
4127   // which don't support them directly, however, may want libcalls, in which
4128   // case they mark them Expand, and we get here.
4129   case ISD::ATOMIC_SWAP:
4130   case ISD::ATOMIC_LOAD_ADD:
4131   case ISD::ATOMIC_LOAD_SUB:
4132   case ISD::ATOMIC_LOAD_AND:
4133   case ISD::ATOMIC_LOAD_CLR:
4134   case ISD::ATOMIC_LOAD_OR:
4135   case ISD::ATOMIC_LOAD_XOR:
4136   case ISD::ATOMIC_LOAD_NAND:
4137   case ISD::ATOMIC_LOAD_MIN:
4138   case ISD::ATOMIC_LOAD_MAX:
4139   case ISD::ATOMIC_LOAD_UMIN:
4140   case ISD::ATOMIC_LOAD_UMAX:
4141   case ISD::ATOMIC_CMP_SWAP: {
4142     MVT VT = cast<AtomicSDNode>(Node)->getMemoryVT().getSimpleVT();
4143     AtomicOrdering Order = cast<AtomicSDNode>(Node)->getOrdering();
4144     RTLIB::Libcall LC = RTLIB::getOUTLINE_ATOMIC(Opc, Order, VT);
4145     EVT RetVT = Node->getValueType(0);
4146     TargetLowering::MakeLibCallOptions CallOptions;
4147     SmallVector<SDValue, 4> Ops;
4148     if (TLI.getLibcallName(LC)) {
4149       // If outline atomic available, prepare its arguments and expand.
4150       Ops.append(Node->op_begin() + 2, Node->op_end());
4151       Ops.push_back(Node->getOperand(1));
4152 
4153     } else {
4154       LC = RTLIB::getSYNC(Opc, VT);
4155       assert(LC != RTLIB::UNKNOWN_LIBCALL &&
4156              "Unexpected atomic op or value type!");
4157       // Arguments for expansion to sync libcall
4158       Ops.append(Node->op_begin() + 1, Node->op_end());
4159     }
4160     std::pair<SDValue, SDValue> Tmp = TLI.makeLibCall(DAG, LC, RetVT,
4161                                                       Ops, CallOptions,
4162                                                       SDLoc(Node),
4163                                                       Node->getOperand(0));
4164     Results.push_back(Tmp.first);
4165     Results.push_back(Tmp.second);
4166     break;
4167   }
4168   case ISD::TRAP: {
4169     // If this operation is not supported, lower it to 'abort()' call
4170     TargetLowering::ArgListTy Args;
4171     TargetLowering::CallLoweringInfo CLI(DAG);
4172     CLI.setDebugLoc(dl)
4173         .setChain(Node->getOperand(0))
4174         .setLibCallee(CallingConv::C, Type::getVoidTy(*DAG.getContext()),
4175                       DAG.getExternalSymbol(
4176                           "abort", TLI.getPointerTy(DAG.getDataLayout())),
4177                       std::move(Args));
4178     std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
4179 
4180     Results.push_back(CallResult.second);
4181     break;
4182   }
4183   case ISD::FMINNUM:
4184   case ISD::STRICT_FMINNUM:
4185     ExpandFPLibCall(Node, RTLIB::FMIN_F32, RTLIB::FMIN_F64,
4186                     RTLIB::FMIN_F80, RTLIB::FMIN_F128,
4187                     RTLIB::FMIN_PPCF128, Results);
4188     break;
4189   case ISD::FMAXNUM:
4190   case ISD::STRICT_FMAXNUM:
4191     ExpandFPLibCall(Node, RTLIB::FMAX_F32, RTLIB::FMAX_F64,
4192                     RTLIB::FMAX_F80, RTLIB::FMAX_F128,
4193                     RTLIB::FMAX_PPCF128, Results);
4194     break;
4195   case ISD::FSQRT:
4196   case ISD::STRICT_FSQRT:
4197     ExpandFPLibCall(Node, RTLIB::SQRT_F32, RTLIB::SQRT_F64,
4198                     RTLIB::SQRT_F80, RTLIB::SQRT_F128,
4199                     RTLIB::SQRT_PPCF128, Results);
4200     break;
4201   case ISD::FCBRT:
4202     ExpandFPLibCall(Node, RTLIB::CBRT_F32, RTLIB::CBRT_F64,
4203                     RTLIB::CBRT_F80, RTLIB::CBRT_F128,
4204                     RTLIB::CBRT_PPCF128, Results);
4205     break;
4206   case ISD::FSIN:
4207   case ISD::STRICT_FSIN:
4208     ExpandFPLibCall(Node, RTLIB::SIN_F32, RTLIB::SIN_F64,
4209                     RTLIB::SIN_F80, RTLIB::SIN_F128,
4210                     RTLIB::SIN_PPCF128, Results);
4211     break;
4212   case ISD::FCOS:
4213   case ISD::STRICT_FCOS:
4214     ExpandFPLibCall(Node, RTLIB::COS_F32, RTLIB::COS_F64,
4215                     RTLIB::COS_F80, RTLIB::COS_F128,
4216                     RTLIB::COS_PPCF128, Results);
4217     break;
4218   case ISD::FSINCOS:
4219     // Expand into sincos libcall.
4220     ExpandSinCosLibCall(Node, Results);
4221     break;
4222   case ISD::FLOG:
4223   case ISD::STRICT_FLOG:
4224     ExpandFPLibCall(Node, RTLIB::LOG_F32, RTLIB::LOG_F64, RTLIB::LOG_F80,
4225                     RTLIB::LOG_F128, RTLIB::LOG_PPCF128, Results);
4226     break;
4227   case ISD::FLOG2:
4228   case ISD::STRICT_FLOG2:
4229     ExpandFPLibCall(Node, RTLIB::LOG2_F32, RTLIB::LOG2_F64, RTLIB::LOG2_F80,
4230                     RTLIB::LOG2_F128, RTLIB::LOG2_PPCF128, Results);
4231     break;
4232   case ISD::FLOG10:
4233   case ISD::STRICT_FLOG10:
4234     ExpandFPLibCall(Node, RTLIB::LOG10_F32, RTLIB::LOG10_F64, RTLIB::LOG10_F80,
4235                     RTLIB::LOG10_F128, RTLIB::LOG10_PPCF128, Results);
4236     break;
4237   case ISD::FEXP:
4238   case ISD::STRICT_FEXP:
4239     ExpandFPLibCall(Node, RTLIB::EXP_F32, RTLIB::EXP_F64, RTLIB::EXP_F80,
4240                     RTLIB::EXP_F128, RTLIB::EXP_PPCF128, Results);
4241     break;
4242   case ISD::FEXP2:
4243   case ISD::STRICT_FEXP2:
4244     ExpandFPLibCall(Node, RTLIB::EXP2_F32, RTLIB::EXP2_F64, RTLIB::EXP2_F80,
4245                     RTLIB::EXP2_F128, RTLIB::EXP2_PPCF128, Results);
4246     break;
4247   case ISD::FTRUNC:
4248   case ISD::STRICT_FTRUNC:
4249     ExpandFPLibCall(Node, RTLIB::TRUNC_F32, RTLIB::TRUNC_F64,
4250                     RTLIB::TRUNC_F80, RTLIB::TRUNC_F128,
4251                     RTLIB::TRUNC_PPCF128, Results);
4252     break;
4253   case ISD::FFLOOR:
4254   case ISD::STRICT_FFLOOR:
4255     ExpandFPLibCall(Node, RTLIB::FLOOR_F32, RTLIB::FLOOR_F64,
4256                     RTLIB::FLOOR_F80, RTLIB::FLOOR_F128,
4257                     RTLIB::FLOOR_PPCF128, Results);
4258     break;
4259   case ISD::FCEIL:
4260   case ISD::STRICT_FCEIL:
4261     ExpandFPLibCall(Node, RTLIB::CEIL_F32, RTLIB::CEIL_F64,
4262                     RTLIB::CEIL_F80, RTLIB::CEIL_F128,
4263                     RTLIB::CEIL_PPCF128, Results);
4264     break;
4265   case ISD::FRINT:
4266   case ISD::STRICT_FRINT:
4267     ExpandFPLibCall(Node, RTLIB::RINT_F32, RTLIB::RINT_F64,
4268                     RTLIB::RINT_F80, RTLIB::RINT_F128,
4269                     RTLIB::RINT_PPCF128, Results);
4270     break;
4271   case ISD::FNEARBYINT:
4272   case ISD::STRICT_FNEARBYINT:
4273     ExpandFPLibCall(Node, RTLIB::NEARBYINT_F32,
4274                     RTLIB::NEARBYINT_F64,
4275                     RTLIB::NEARBYINT_F80,
4276                     RTLIB::NEARBYINT_F128,
4277                     RTLIB::NEARBYINT_PPCF128, Results);
4278     break;
4279   case ISD::FROUND:
4280   case ISD::STRICT_FROUND:
4281     ExpandFPLibCall(Node, RTLIB::ROUND_F32,
4282                     RTLIB::ROUND_F64,
4283                     RTLIB::ROUND_F80,
4284                     RTLIB::ROUND_F128,
4285                     RTLIB::ROUND_PPCF128, Results);
4286     break;
4287   case ISD::FROUNDEVEN:
4288   case ISD::STRICT_FROUNDEVEN:
4289     ExpandFPLibCall(Node, RTLIB::ROUNDEVEN_F32,
4290                     RTLIB::ROUNDEVEN_F64,
4291                     RTLIB::ROUNDEVEN_F80,
4292                     RTLIB::ROUNDEVEN_F128,
4293                     RTLIB::ROUNDEVEN_PPCF128, Results);
4294     break;
4295   case ISD::FPOWI:
4296   case ISD::STRICT_FPOWI: {
4297     RTLIB::Libcall LC;
4298     switch (Node->getSimpleValueType(0).SimpleTy) {
4299     default: llvm_unreachable("Unexpected request for libcall!");
4300     case MVT::f32: LC = RTLIB::POWI_F32; break;
4301     case MVT::f64: LC = RTLIB::POWI_F64; break;
4302     case MVT::f80: LC = RTLIB::POWI_F80; break;
4303     case MVT::f128: LC = RTLIB::POWI_F128; break;
4304     case MVT::ppcf128: LC = RTLIB::POWI_PPCF128; break;
4305     }
4306     if (!TLI.getLibcallName(LC)) {
4307       // Some targets don't have a powi libcall; use pow instead.
4308       SDValue Exponent = DAG.getNode(ISD::SINT_TO_FP, SDLoc(Node),
4309                                      Node->getValueType(0),
4310                                      Node->getOperand(1));
4311       Results.push_back(DAG.getNode(ISD::FPOW, SDLoc(Node),
4312                                     Node->getValueType(0), Node->getOperand(0),
4313                                     Exponent));
4314       break;
4315     }
4316     ExpandFPLibCall(Node, RTLIB::POWI_F32, RTLIB::POWI_F64,
4317                     RTLIB::POWI_F80, RTLIB::POWI_F128,
4318                     RTLIB::POWI_PPCF128, Results);
4319     break;
4320   }
4321   case ISD::FPOW:
4322   case ISD::STRICT_FPOW:
4323     ExpandFPLibCall(Node, RTLIB::POW_F32, RTLIB::POW_F64, RTLIB::POW_F80,
4324                     RTLIB::POW_F128, RTLIB::POW_PPCF128, Results);
4325     break;
4326   case ISD::LROUND:
4327   case ISD::STRICT_LROUND:
4328     ExpandArgFPLibCall(Node, RTLIB::LROUND_F32,
4329                        RTLIB::LROUND_F64, RTLIB::LROUND_F80,
4330                        RTLIB::LROUND_F128,
4331                        RTLIB::LROUND_PPCF128, Results);
4332     break;
4333   case ISD::LLROUND:
4334   case ISD::STRICT_LLROUND:
4335     ExpandArgFPLibCall(Node, RTLIB::LLROUND_F32,
4336                        RTLIB::LLROUND_F64, RTLIB::LLROUND_F80,
4337                        RTLIB::LLROUND_F128,
4338                        RTLIB::LLROUND_PPCF128, Results);
4339     break;
4340   case ISD::LRINT:
4341   case ISD::STRICT_LRINT:
4342     ExpandArgFPLibCall(Node, RTLIB::LRINT_F32,
4343                        RTLIB::LRINT_F64, RTLIB::LRINT_F80,
4344                        RTLIB::LRINT_F128,
4345                        RTLIB::LRINT_PPCF128, Results);
4346     break;
4347   case ISD::LLRINT:
4348   case ISD::STRICT_LLRINT:
4349     ExpandArgFPLibCall(Node, RTLIB::LLRINT_F32,
4350                        RTLIB::LLRINT_F64, RTLIB::LLRINT_F80,
4351                        RTLIB::LLRINT_F128,
4352                        RTLIB::LLRINT_PPCF128, Results);
4353     break;
4354   case ISD::FDIV:
4355   case ISD::STRICT_FDIV:
4356     ExpandFPLibCall(Node, RTLIB::DIV_F32, RTLIB::DIV_F64,
4357                     RTLIB::DIV_F80, RTLIB::DIV_F128,
4358                     RTLIB::DIV_PPCF128, Results);
4359     break;
4360   case ISD::FREM:
4361   case ISD::STRICT_FREM:
4362     ExpandFPLibCall(Node, RTLIB::REM_F32, RTLIB::REM_F64,
4363                     RTLIB::REM_F80, RTLIB::REM_F128,
4364                     RTLIB::REM_PPCF128, Results);
4365     break;
4366   case ISD::FMA:
4367   case ISD::STRICT_FMA:
4368     ExpandFPLibCall(Node, RTLIB::FMA_F32, RTLIB::FMA_F64,
4369                     RTLIB::FMA_F80, RTLIB::FMA_F128,
4370                     RTLIB::FMA_PPCF128, Results);
4371     break;
4372   case ISD::FADD:
4373   case ISD::STRICT_FADD:
4374     ExpandFPLibCall(Node, RTLIB::ADD_F32, RTLIB::ADD_F64,
4375                     RTLIB::ADD_F80, RTLIB::ADD_F128,
4376                     RTLIB::ADD_PPCF128, Results);
4377     break;
4378   case ISD::FMUL:
4379   case ISD::STRICT_FMUL:
4380     ExpandFPLibCall(Node, RTLIB::MUL_F32, RTLIB::MUL_F64,
4381                     RTLIB::MUL_F80, RTLIB::MUL_F128,
4382                     RTLIB::MUL_PPCF128, Results);
4383     break;
4384   case ISD::FP16_TO_FP:
4385     if (Node->getValueType(0) == MVT::f32) {
4386       Results.push_back(ExpandLibCall(RTLIB::FPEXT_F16_F32, Node, false));
4387     }
4388     break;
4389   case ISD::STRICT_FP16_TO_FP: {
4390     if (Node->getValueType(0) == MVT::f32) {
4391       TargetLowering::MakeLibCallOptions CallOptions;
4392       std::pair<SDValue, SDValue> Tmp = TLI.makeLibCall(
4393           DAG, RTLIB::FPEXT_F16_F32, MVT::f32, Node->getOperand(1), CallOptions,
4394           SDLoc(Node), Node->getOperand(0));
4395       Results.push_back(Tmp.first);
4396       Results.push_back(Tmp.second);
4397     }
4398     break;
4399   }
4400   case ISD::FP_TO_FP16: {
4401     RTLIB::Libcall LC =
4402         RTLIB::getFPROUND(Node->getOperand(0).getValueType(), MVT::f16);
4403     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unable to expand fp_to_fp16");
4404     Results.push_back(ExpandLibCall(LC, Node, false));
4405     break;
4406   }
4407   case ISD::STRICT_SINT_TO_FP:
4408   case ISD::STRICT_UINT_TO_FP:
4409   case ISD::SINT_TO_FP:
4410   case ISD::UINT_TO_FP: {
4411     // TODO - Common the code with DAGTypeLegalizer::SoftenFloatRes_XINT_TO_FP
4412     bool IsStrict = Node->isStrictFPOpcode();
4413     bool Signed = Node->getOpcode() == ISD::SINT_TO_FP ||
4414                   Node->getOpcode() == ISD::STRICT_SINT_TO_FP;
4415     EVT SVT = Node->getOperand(IsStrict ? 1 : 0).getValueType();
4416     EVT RVT = Node->getValueType(0);
4417     EVT NVT = EVT();
4418     SDLoc dl(Node);
4419 
4420     // Even if the input is legal, no libcall may exactly match, eg. we don't
4421     // have i1 -> fp conversions. So, it needs to be promoted to a larger type,
4422     // eg: i13 -> fp. Then, look for an appropriate libcall.
4423     RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
4424     for (unsigned t = MVT::FIRST_INTEGER_VALUETYPE;
4425          t <= MVT::LAST_INTEGER_VALUETYPE && LC == RTLIB::UNKNOWN_LIBCALL;
4426          ++t) {
4427       NVT = (MVT::SimpleValueType)t;
4428       // The source needs to big enough to hold the operand.
4429       if (NVT.bitsGE(SVT))
4430         LC = Signed ? RTLIB::getSINTTOFP(NVT, RVT)
4431                     : RTLIB::getUINTTOFP(NVT, RVT);
4432     }
4433     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unable to legalize as libcall");
4434 
4435     SDValue Chain = IsStrict ? Node->getOperand(0) : SDValue();
4436     // Sign/zero extend the argument if the libcall takes a larger type.
4437     SDValue Op = DAG.getNode(Signed ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND, dl,
4438                              NVT, Node->getOperand(IsStrict ? 1 : 0));
4439     TargetLowering::MakeLibCallOptions CallOptions;
4440     CallOptions.setSExt(Signed);
4441     std::pair<SDValue, SDValue> Tmp =
4442         TLI.makeLibCall(DAG, LC, RVT, Op, CallOptions, dl, Chain);
4443     Results.push_back(Tmp.first);
4444     if (IsStrict)
4445       Results.push_back(Tmp.second);
4446     break;
4447   }
4448   case ISD::FP_TO_SINT:
4449   case ISD::FP_TO_UINT:
4450   case ISD::STRICT_FP_TO_SINT:
4451   case ISD::STRICT_FP_TO_UINT: {
4452     // TODO - Common the code with DAGTypeLegalizer::SoftenFloatOp_FP_TO_XINT.
4453     bool IsStrict = Node->isStrictFPOpcode();
4454     bool Signed = Node->getOpcode() == ISD::FP_TO_SINT ||
4455                   Node->getOpcode() == ISD::STRICT_FP_TO_SINT;
4456 
4457     SDValue Op = Node->getOperand(IsStrict ? 1 : 0);
4458     EVT SVT = Op.getValueType();
4459     EVT RVT = Node->getValueType(0);
4460     EVT NVT = EVT();
4461     SDLoc dl(Node);
4462 
4463     // Even if the result is legal, no libcall may exactly match, eg. we don't
4464     // have fp -> i1 conversions. So, it needs to be promoted to a larger type,
4465     // eg: fp -> i32. Then, look for an appropriate libcall.
4466     RTLIB::Libcall LC = RTLIB::UNKNOWN_LIBCALL;
4467     for (unsigned IntVT = MVT::FIRST_INTEGER_VALUETYPE;
4468          IntVT <= MVT::LAST_INTEGER_VALUETYPE && LC == RTLIB::UNKNOWN_LIBCALL;
4469          ++IntVT) {
4470       NVT = (MVT::SimpleValueType)IntVT;
4471       // The type needs to big enough to hold the result.
4472       if (NVT.bitsGE(RVT))
4473         LC = Signed ? RTLIB::getFPTOSINT(SVT, NVT)
4474                     : RTLIB::getFPTOUINT(SVT, NVT);
4475     }
4476     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unable to legalize as libcall");
4477 
4478     SDValue Chain = IsStrict ? Node->getOperand(0) : SDValue();
4479     TargetLowering::MakeLibCallOptions CallOptions;
4480     std::pair<SDValue, SDValue> Tmp =
4481         TLI.makeLibCall(DAG, LC, NVT, Op, CallOptions, dl, Chain);
4482 
4483     // Truncate the result if the libcall returns a larger type.
4484     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, RVT, Tmp.first));
4485     if (IsStrict)
4486       Results.push_back(Tmp.second);
4487     break;
4488   }
4489 
4490   case ISD::FP_ROUND:
4491   case ISD::STRICT_FP_ROUND: {
4492     // X = FP_ROUND(Y, TRUNC)
4493     // TRUNC is a flag, which is always an integer that is zero or one.
4494     // If TRUNC is 0, this is a normal rounding, if it is 1, this FP_ROUND
4495     // is known to not change the value of Y.
4496     // We can only expand it into libcall if the TRUNC is 0.
4497     bool IsStrict = Node->isStrictFPOpcode();
4498     SDValue Op = Node->getOperand(IsStrict ? 1 : 0);
4499     SDValue Chain = IsStrict ? Node->getOperand(0) : SDValue();
4500     EVT VT = Node->getValueType(0);
4501     assert(cast<ConstantSDNode>(Node->getOperand(IsStrict ? 2 : 1))
4502                ->isNullValue() &&
4503            "Unable to expand as libcall if it is not normal rounding");
4504 
4505     RTLIB::Libcall LC = RTLIB::getFPROUND(Op.getValueType(), VT);
4506     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unable to legalize as libcall");
4507 
4508     TargetLowering::MakeLibCallOptions CallOptions;
4509     std::pair<SDValue, SDValue> Tmp =
4510         TLI.makeLibCall(DAG, LC, VT, Op, CallOptions, SDLoc(Node), Chain);
4511     Results.push_back(Tmp.first);
4512     if (IsStrict)
4513       Results.push_back(Tmp.second);
4514     break;
4515   }
4516   case ISD::FP_EXTEND: {
4517     Results.push_back(
4518         ExpandLibCall(RTLIB::getFPEXT(Node->getOperand(0).getValueType(),
4519                                       Node->getValueType(0)),
4520                       Node, false));
4521     break;
4522   }
4523   case ISD::STRICT_FP_EXTEND:
4524   case ISD::STRICT_FP_TO_FP16: {
4525     RTLIB::Libcall LC =
4526         Node->getOpcode() == ISD::STRICT_FP_TO_FP16
4527             ? RTLIB::getFPROUND(Node->getOperand(1).getValueType(), MVT::f16)
4528             : RTLIB::getFPEXT(Node->getOperand(1).getValueType(),
4529                               Node->getValueType(0));
4530     assert(LC != RTLIB::UNKNOWN_LIBCALL && "Unable to legalize as libcall");
4531 
4532     TargetLowering::MakeLibCallOptions CallOptions;
4533     std::pair<SDValue, SDValue> Tmp =
4534         TLI.makeLibCall(DAG, LC, Node->getValueType(0), Node->getOperand(1),
4535                         CallOptions, SDLoc(Node), Node->getOperand(0));
4536     Results.push_back(Tmp.first);
4537     Results.push_back(Tmp.second);
4538     break;
4539   }
4540   case ISD::FSUB:
4541   case ISD::STRICT_FSUB:
4542     ExpandFPLibCall(Node, RTLIB::SUB_F32, RTLIB::SUB_F64,
4543                     RTLIB::SUB_F80, RTLIB::SUB_F128,
4544                     RTLIB::SUB_PPCF128, Results);
4545     break;
4546   case ISD::SREM:
4547     Results.push_back(ExpandIntLibCall(Node, true,
4548                                        RTLIB::SREM_I8,
4549                                        RTLIB::SREM_I16, RTLIB::SREM_I32,
4550                                        RTLIB::SREM_I64, RTLIB::SREM_I128));
4551     break;
4552   case ISD::UREM:
4553     Results.push_back(ExpandIntLibCall(Node, false,
4554                                        RTLIB::UREM_I8,
4555                                        RTLIB::UREM_I16, RTLIB::UREM_I32,
4556                                        RTLIB::UREM_I64, RTLIB::UREM_I128));
4557     break;
4558   case ISD::SDIV:
4559     Results.push_back(ExpandIntLibCall(Node, true,
4560                                        RTLIB::SDIV_I8,
4561                                        RTLIB::SDIV_I16, RTLIB::SDIV_I32,
4562                                        RTLIB::SDIV_I64, RTLIB::SDIV_I128));
4563     break;
4564   case ISD::UDIV:
4565     Results.push_back(ExpandIntLibCall(Node, false,
4566                                        RTLIB::UDIV_I8,
4567                                        RTLIB::UDIV_I16, RTLIB::UDIV_I32,
4568                                        RTLIB::UDIV_I64, RTLIB::UDIV_I128));
4569     break;
4570   case ISD::SDIVREM:
4571   case ISD::UDIVREM:
4572     // Expand into divrem libcall
4573     ExpandDivRemLibCall(Node, Results);
4574     break;
4575   case ISD::MUL:
4576     Results.push_back(ExpandIntLibCall(Node, false,
4577                                        RTLIB::MUL_I8,
4578                                        RTLIB::MUL_I16, RTLIB::MUL_I32,
4579                                        RTLIB::MUL_I64, RTLIB::MUL_I128));
4580     break;
4581   case ISD::CTLZ_ZERO_UNDEF:
4582     switch (Node->getSimpleValueType(0).SimpleTy) {
4583     default:
4584       llvm_unreachable("LibCall explicitly requested, but not available");
4585     case MVT::i32:
4586       Results.push_back(ExpandLibCall(RTLIB::CTLZ_I32, Node, false));
4587       break;
4588     case MVT::i64:
4589       Results.push_back(ExpandLibCall(RTLIB::CTLZ_I64, Node, false));
4590       break;
4591     case MVT::i128:
4592       Results.push_back(ExpandLibCall(RTLIB::CTLZ_I128, Node, false));
4593       break;
4594     }
4595     break;
4596   }
4597 
4598   // Replace the original node with the legalized result.
4599   if (!Results.empty()) {
4600     LLVM_DEBUG(dbgs() << "Successfully converted node to libcall\n");
4601     ReplaceNode(Node, Results.data());
4602   } else
4603     LLVM_DEBUG(dbgs() << "Could not convert node to libcall\n");
4604 }
4605 
4606 // Determine the vector type to use in place of an original scalar element when
4607 // promoting equally sized vectors.
4608 static MVT getPromotedVectorElementType(const TargetLowering &TLI,
4609                                         MVT EltVT, MVT NewEltVT) {
4610   unsigned OldEltsPerNewElt = EltVT.getSizeInBits() / NewEltVT.getSizeInBits();
4611   MVT MidVT = MVT::getVectorVT(NewEltVT, OldEltsPerNewElt);
4612   assert(TLI.isTypeLegal(MidVT) && "unexpected");
4613   return MidVT;
4614 }
4615 
4616 void SelectionDAGLegalize::PromoteNode(SDNode *Node) {
4617   LLVM_DEBUG(dbgs() << "Trying to promote node\n");
4618   SmallVector<SDValue, 8> Results;
4619   MVT OVT = Node->getSimpleValueType(0);
4620   if (Node->getOpcode() == ISD::UINT_TO_FP ||
4621       Node->getOpcode() == ISD::SINT_TO_FP ||
4622       Node->getOpcode() == ISD::SETCC ||
4623       Node->getOpcode() == ISD::EXTRACT_VECTOR_ELT ||
4624       Node->getOpcode() == ISD::INSERT_VECTOR_ELT) {
4625     OVT = Node->getOperand(0).getSimpleValueType();
4626   }
4627   if (Node->getOpcode() == ISD::STRICT_UINT_TO_FP ||
4628       Node->getOpcode() == ISD::STRICT_SINT_TO_FP ||
4629       Node->getOpcode() == ISD::STRICT_FSETCC ||
4630       Node->getOpcode() == ISD::STRICT_FSETCCS)
4631     OVT = Node->getOperand(1).getSimpleValueType();
4632   if (Node->getOpcode() == ISD::BR_CC)
4633     OVT = Node->getOperand(2).getSimpleValueType();
4634   MVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), OVT);
4635   SDLoc dl(Node);
4636   SDValue Tmp1, Tmp2, Tmp3;
4637   switch (Node->getOpcode()) {
4638   case ISD::CTTZ:
4639   case ISD::CTTZ_ZERO_UNDEF:
4640   case ISD::CTLZ:
4641   case ISD::CTLZ_ZERO_UNDEF:
4642   case ISD::CTPOP:
4643     // Zero extend the argument unless its cttz, then use any_extend.
4644     if (Node->getOpcode() == ISD::CTTZ ||
4645         Node->getOpcode() == ISD::CTTZ_ZERO_UNDEF)
4646       Tmp1 = DAG.getNode(ISD::ANY_EXTEND, dl, NVT, Node->getOperand(0));
4647     else
4648       Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Node->getOperand(0));
4649 
4650     if (Node->getOpcode() == ISD::CTTZ) {
4651       // The count is the same in the promoted type except if the original
4652       // value was zero.  This can be handled by setting the bit just off
4653       // the top of the original type.
4654       auto TopBit = APInt::getOneBitSet(NVT.getSizeInBits(),
4655                                         OVT.getSizeInBits());
4656       Tmp1 = DAG.getNode(ISD::OR, dl, NVT, Tmp1,
4657                          DAG.getConstant(TopBit, dl, NVT));
4658     }
4659     // Perform the larger operation. For CTPOP and CTTZ_ZERO_UNDEF, this is
4660     // already the correct result.
4661     Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
4662     if (Node->getOpcode() == ISD::CTLZ ||
4663         Node->getOpcode() == ISD::CTLZ_ZERO_UNDEF) {
4664       // Tmp1 = Tmp1 - (sizeinbits(NVT) - sizeinbits(Old VT))
4665       Tmp1 = DAG.getNode(ISD::SUB, dl, NVT, Tmp1,
4666                           DAG.getConstant(NVT.getSizeInBits() -
4667                                           OVT.getSizeInBits(), dl, NVT));
4668     }
4669     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp1));
4670     break;
4671   case ISD::BITREVERSE:
4672   case ISD::BSWAP: {
4673     unsigned DiffBits = NVT.getSizeInBits() - OVT.getSizeInBits();
4674     Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Node->getOperand(0));
4675     Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
4676     Tmp1 = DAG.getNode(
4677         ISD::SRL, dl, NVT, Tmp1,
4678         DAG.getConstant(DiffBits, dl,
4679                         TLI.getShiftAmountTy(NVT, DAG.getDataLayout())));
4680 
4681     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp1));
4682     break;
4683   }
4684   case ISD::FP_TO_UINT:
4685   case ISD::STRICT_FP_TO_UINT:
4686   case ISD::FP_TO_SINT:
4687   case ISD::STRICT_FP_TO_SINT:
4688     PromoteLegalFP_TO_INT(Node, dl, Results);
4689     break;
4690   case ISD::FP_TO_UINT_SAT:
4691   case ISD::FP_TO_SINT_SAT:
4692     Results.push_back(PromoteLegalFP_TO_INT_SAT(Node, dl));
4693     break;
4694   case ISD::UINT_TO_FP:
4695   case ISD::STRICT_UINT_TO_FP:
4696   case ISD::SINT_TO_FP:
4697   case ISD::STRICT_SINT_TO_FP:
4698     PromoteLegalINT_TO_FP(Node, dl, Results);
4699     break;
4700   case ISD::VAARG: {
4701     SDValue Chain = Node->getOperand(0); // Get the chain.
4702     SDValue Ptr = Node->getOperand(1); // Get the pointer.
4703 
4704     unsigned TruncOp;
4705     if (OVT.isVector()) {
4706       TruncOp = ISD::BITCAST;
4707     } else {
4708       assert(OVT.isInteger()
4709         && "VAARG promotion is supported only for vectors or integer types");
4710       TruncOp = ISD::TRUNCATE;
4711     }
4712 
4713     // Perform the larger operation, then convert back
4714     Tmp1 = DAG.getVAArg(NVT, dl, Chain, Ptr, Node->getOperand(2),
4715              Node->getConstantOperandVal(3));
4716     Chain = Tmp1.getValue(1);
4717 
4718     Tmp2 = DAG.getNode(TruncOp, dl, OVT, Tmp1);
4719 
4720     // Modified the chain result - switch anything that used the old chain to
4721     // use the new one.
4722     DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 0), Tmp2);
4723     DAG.ReplaceAllUsesOfValueWith(SDValue(Node, 1), Chain);
4724     if (UpdatedNodes) {
4725       UpdatedNodes->insert(Tmp2.getNode());
4726       UpdatedNodes->insert(Chain.getNode());
4727     }
4728     ReplacedNode(Node);
4729     break;
4730   }
4731   case ISD::MUL:
4732   case ISD::SDIV:
4733   case ISD::SREM:
4734   case ISD::UDIV:
4735   case ISD::UREM:
4736   case ISD::AND:
4737   case ISD::OR:
4738   case ISD::XOR: {
4739     unsigned ExtOp, TruncOp;
4740     if (OVT.isVector()) {
4741       ExtOp   = ISD::BITCAST;
4742       TruncOp = ISD::BITCAST;
4743     } else {
4744       assert(OVT.isInteger() && "Cannot promote logic operation");
4745 
4746       switch (Node->getOpcode()) {
4747       default:
4748         ExtOp = ISD::ANY_EXTEND;
4749         break;
4750       case ISD::SDIV:
4751       case ISD::SREM:
4752         ExtOp = ISD::SIGN_EXTEND;
4753         break;
4754       case ISD::UDIV:
4755       case ISD::UREM:
4756         ExtOp = ISD::ZERO_EXTEND;
4757         break;
4758       }
4759       TruncOp = ISD::TRUNCATE;
4760     }
4761     // Promote each of the values to the new type.
4762     Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
4763     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
4764     // Perform the larger operation, then convert back
4765     Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2);
4766     Results.push_back(DAG.getNode(TruncOp, dl, OVT, Tmp1));
4767     break;
4768   }
4769   case ISD::UMUL_LOHI:
4770   case ISD::SMUL_LOHI: {
4771     // Promote to a multiply in a wider integer type.
4772     unsigned ExtOp = Node->getOpcode() == ISD::UMUL_LOHI ? ISD::ZERO_EXTEND
4773                                                          : ISD::SIGN_EXTEND;
4774     Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
4775     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
4776     Tmp1 = DAG.getNode(ISD::MUL, dl, NVT, Tmp1, Tmp2);
4777 
4778     auto &DL = DAG.getDataLayout();
4779     unsigned OriginalSize = OVT.getScalarSizeInBits();
4780     Tmp2 = DAG.getNode(
4781         ISD::SRL, dl, NVT, Tmp1,
4782         DAG.getConstant(OriginalSize, dl, TLI.getScalarShiftAmountTy(DL, NVT)));
4783     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp1));
4784     Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp2));
4785     break;
4786   }
4787   case ISD::SELECT: {
4788     unsigned ExtOp, TruncOp;
4789     if (Node->getValueType(0).isVector() ||
4790         Node->getValueType(0).getSizeInBits() == NVT.getSizeInBits()) {
4791       ExtOp   = ISD::BITCAST;
4792       TruncOp = ISD::BITCAST;
4793     } else if (Node->getValueType(0).isInteger()) {
4794       ExtOp   = ISD::ANY_EXTEND;
4795       TruncOp = ISD::TRUNCATE;
4796     } else {
4797       ExtOp   = ISD::FP_EXTEND;
4798       TruncOp = ISD::FP_ROUND;
4799     }
4800     Tmp1 = Node->getOperand(0);
4801     // Promote each of the values to the new type.
4802     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
4803     Tmp3 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(2));
4804     // Perform the larger operation, then round down.
4805     Tmp1 = DAG.getSelect(dl, NVT, Tmp1, Tmp2, Tmp3);
4806     Tmp1->setFlags(Node->getFlags());
4807     if (TruncOp != ISD::FP_ROUND)
4808       Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1);
4809     else
4810       Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1,
4811                          DAG.getIntPtrConstant(0, dl));
4812     Results.push_back(Tmp1);
4813     break;
4814   }
4815   case ISD::VECTOR_SHUFFLE: {
4816     ArrayRef<int> Mask = cast<ShuffleVectorSDNode>(Node)->getMask();
4817 
4818     // Cast the two input vectors.
4819     Tmp1 = DAG.getNode(ISD::BITCAST, dl, NVT, Node->getOperand(0));
4820     Tmp2 = DAG.getNode(ISD::BITCAST, dl, NVT, Node->getOperand(1));
4821 
4822     // Convert the shuffle mask to the right # elements.
4823     Tmp1 = ShuffleWithNarrowerEltType(NVT, OVT, dl, Tmp1, Tmp2, Mask);
4824     Tmp1 = DAG.getNode(ISD::BITCAST, dl, OVT, Tmp1);
4825     Results.push_back(Tmp1);
4826     break;
4827   }
4828   case ISD::SETCC:
4829   case ISD::STRICT_FSETCC:
4830   case ISD::STRICT_FSETCCS: {
4831     unsigned ExtOp = ISD::FP_EXTEND;
4832     if (NVT.isInteger()) {
4833       ISD::CondCode CCCode = cast<CondCodeSDNode>(Node->getOperand(2))->get();
4834       ExtOp = isSignedIntSetCC(CCCode) ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND;
4835     }
4836     if (Node->isStrictFPOpcode()) {
4837       SDValue InChain = Node->getOperand(0);
4838       std::tie(Tmp1, std::ignore) =
4839           DAG.getStrictFPExtendOrRound(Node->getOperand(1), InChain, dl, NVT);
4840       std::tie(Tmp2, std::ignore) =
4841           DAG.getStrictFPExtendOrRound(Node->getOperand(2), InChain, dl, NVT);
4842       SmallVector<SDValue, 2> TmpChains = {Tmp1.getValue(1), Tmp2.getValue(1)};
4843       SDValue OutChain = DAG.getTokenFactor(dl, TmpChains);
4844       SDVTList VTs = DAG.getVTList(Node->getValueType(0), MVT::Other);
4845       Results.push_back(DAG.getNode(Node->getOpcode(), dl, VTs,
4846                                     {OutChain, Tmp1, Tmp2, Node->getOperand(3)},
4847                                     Node->getFlags()));
4848       Results.push_back(Results.back().getValue(1));
4849       break;
4850     }
4851     Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
4852     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
4853     Results.push_back(DAG.getNode(ISD::SETCC, dl, Node->getValueType(0), Tmp1,
4854                                   Tmp2, Node->getOperand(2), Node->getFlags()));
4855     break;
4856   }
4857   case ISD::BR_CC: {
4858     unsigned ExtOp = ISD::FP_EXTEND;
4859     if (NVT.isInteger()) {
4860       ISD::CondCode CCCode =
4861         cast<CondCodeSDNode>(Node->getOperand(1))->get();
4862       ExtOp = isSignedIntSetCC(CCCode) ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND;
4863     }
4864     Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(2));
4865     Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(3));
4866     Results.push_back(DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0),
4867                                   Node->getOperand(0), Node->getOperand(1),
4868                                   Tmp1, Tmp2, Node->getOperand(4)));
4869     break;
4870   }
4871   case ISD::FADD:
4872   case ISD::FSUB:
4873   case ISD::FMUL:
4874   case ISD::FDIV:
4875   case ISD::FREM:
4876   case ISD::FMINNUM:
4877   case ISD::FMAXNUM:
4878   case ISD::FPOW:
4879     Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
4880     Tmp2 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(1));
4881     Tmp3 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2,
4882                        Node->getFlags());
4883     Results.push_back(DAG.getNode(ISD::FP_ROUND, dl, OVT,
4884                                   Tmp3, DAG.getIntPtrConstant(0, dl)));
4885     break;
4886   case ISD::STRICT_FREM:
4887   case ISD::STRICT_FPOW:
4888     Tmp1 = DAG.getNode(ISD::STRICT_FP_EXTEND, dl, {NVT, MVT::Other},
4889                        {Node->getOperand(0), Node->getOperand(1)});
4890     Tmp2 = DAG.getNode(ISD::STRICT_FP_EXTEND, dl, {NVT, MVT::Other},
4891                        {Node->getOperand(0), Node->getOperand(2)});
4892     Tmp3 = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Tmp1.getValue(1),
4893                        Tmp2.getValue(1));
4894     Tmp1 = DAG.getNode(Node->getOpcode(), dl, {NVT, MVT::Other},
4895                        {Tmp3, Tmp1, Tmp2});
4896     Tmp1 = DAG.getNode(ISD::STRICT_FP_ROUND, dl, {OVT, MVT::Other},
4897                        {Tmp1.getValue(1), Tmp1, DAG.getIntPtrConstant(0, dl)});
4898     Results.push_back(Tmp1);
4899     Results.push_back(Tmp1.getValue(1));
4900     break;
4901   case ISD::FMA:
4902     Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
4903     Tmp2 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(1));
4904     Tmp3 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(2));
4905     Results.push_back(
4906         DAG.getNode(ISD::FP_ROUND, dl, OVT,
4907                     DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2, Tmp3),
4908                     DAG.getIntPtrConstant(0, dl)));
4909     break;
4910   case ISD::FCOPYSIGN:
4911   case ISD::FPOWI: {
4912     Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
4913     Tmp2 = Node->getOperand(1);
4914     Tmp3 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2);
4915 
4916     // fcopysign doesn't change anything but the sign bit, so
4917     //   (fp_round (fcopysign (fpext a), b))
4918     // is as precise as
4919     //   (fp_round (fpext a))
4920     // which is a no-op. Mark it as a TRUNCating FP_ROUND.
4921     const bool isTrunc = (Node->getOpcode() == ISD::FCOPYSIGN);
4922     Results.push_back(DAG.getNode(ISD::FP_ROUND, dl, OVT,
4923                                   Tmp3, DAG.getIntPtrConstant(isTrunc, dl)));
4924     break;
4925   }
4926   case ISD::FFLOOR:
4927   case ISD::FCEIL:
4928   case ISD::FRINT:
4929   case ISD::FNEARBYINT:
4930   case ISD::FROUND:
4931   case ISD::FROUNDEVEN:
4932   case ISD::FTRUNC:
4933   case ISD::FNEG:
4934   case ISD::FSQRT:
4935   case ISD::FSIN:
4936   case ISD::FCOS:
4937   case ISD::FLOG:
4938   case ISD::FLOG2:
4939   case ISD::FLOG10:
4940   case ISD::FABS:
4941   case ISD::FEXP:
4942   case ISD::FEXP2:
4943     Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
4944     Tmp2 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
4945     Results.push_back(DAG.getNode(ISD::FP_ROUND, dl, OVT,
4946                                   Tmp2, DAG.getIntPtrConstant(0, dl)));
4947     break;
4948   case ISD::STRICT_FFLOOR:
4949   case ISD::STRICT_FCEIL:
4950   case ISD::STRICT_FSIN:
4951   case ISD::STRICT_FCOS:
4952   case ISD::STRICT_FLOG:
4953   case ISD::STRICT_FLOG10:
4954   case ISD::STRICT_FEXP:
4955     Tmp1 = DAG.getNode(ISD::STRICT_FP_EXTEND, dl, {NVT, MVT::Other},
4956                        {Node->getOperand(0), Node->getOperand(1)});
4957     Tmp2 = DAG.getNode(Node->getOpcode(), dl, {NVT, MVT::Other},
4958                        {Tmp1.getValue(1), Tmp1});
4959     Tmp3 = DAG.getNode(ISD::STRICT_FP_ROUND, dl, {OVT, MVT::Other},
4960                        {Tmp2.getValue(1), Tmp2, DAG.getIntPtrConstant(0, dl)});
4961     Results.push_back(Tmp3);
4962     Results.push_back(Tmp3.getValue(1));
4963     break;
4964   case ISD::BUILD_VECTOR: {
4965     MVT EltVT = OVT.getVectorElementType();
4966     MVT NewEltVT = NVT.getVectorElementType();
4967 
4968     // Handle bitcasts to a different vector type with the same total bit size
4969     //
4970     // e.g. v2i64 = build_vector i64:x, i64:y => v4i32
4971     //  =>
4972     //  v4i32 = concat_vectors (v2i32 (bitcast i64:x)), (v2i32 (bitcast i64:y))
4973 
4974     assert(NVT.isVector() && OVT.getSizeInBits() == NVT.getSizeInBits() &&
4975            "Invalid promote type for build_vector");
4976     assert(NewEltVT.bitsLT(EltVT) && "not handled");
4977 
4978     MVT MidVT = getPromotedVectorElementType(TLI, EltVT, NewEltVT);
4979 
4980     SmallVector<SDValue, 8> NewOps;
4981     for (unsigned I = 0, E = Node->getNumOperands(); I != E; ++I) {
4982       SDValue Op = Node->getOperand(I);
4983       NewOps.push_back(DAG.getNode(ISD::BITCAST, SDLoc(Op), MidVT, Op));
4984     }
4985 
4986     SDLoc SL(Node);
4987     SDValue Concat = DAG.getNode(ISD::CONCAT_VECTORS, SL, NVT, NewOps);
4988     SDValue CvtVec = DAG.getNode(ISD::BITCAST, SL, OVT, Concat);
4989     Results.push_back(CvtVec);
4990     break;
4991   }
4992   case ISD::EXTRACT_VECTOR_ELT: {
4993     MVT EltVT = OVT.getVectorElementType();
4994     MVT NewEltVT = NVT.getVectorElementType();
4995 
4996     // Handle bitcasts to a different vector type with the same total bit size.
4997     //
4998     // e.g. v2i64 = extract_vector_elt x:v2i64, y:i32
4999     //  =>
5000     //  v4i32:castx = bitcast x:v2i64
5001     //
5002     // i64 = bitcast
5003     //   (v2i32 build_vector (i32 (extract_vector_elt castx, (2 * y))),
5004     //                       (i32 (extract_vector_elt castx, (2 * y + 1)))
5005     //
5006 
5007     assert(NVT.isVector() && OVT.getSizeInBits() == NVT.getSizeInBits() &&
5008            "Invalid promote type for extract_vector_elt");
5009     assert(NewEltVT.bitsLT(EltVT) && "not handled");
5010 
5011     MVT MidVT = getPromotedVectorElementType(TLI, EltVT, NewEltVT);
5012     unsigned NewEltsPerOldElt = MidVT.getVectorNumElements();
5013 
5014     SDValue Idx = Node->getOperand(1);
5015     EVT IdxVT = Idx.getValueType();
5016     SDLoc SL(Node);
5017     SDValue Factor = DAG.getConstant(NewEltsPerOldElt, SL, IdxVT);
5018     SDValue NewBaseIdx = DAG.getNode(ISD::MUL, SL, IdxVT, Idx, Factor);
5019 
5020     SDValue CastVec = DAG.getNode(ISD::BITCAST, SL, NVT, Node->getOperand(0));
5021 
5022     SmallVector<SDValue, 8> NewOps;
5023     for (unsigned I = 0; I < NewEltsPerOldElt; ++I) {
5024       SDValue IdxOffset = DAG.getConstant(I, SL, IdxVT);
5025       SDValue TmpIdx = DAG.getNode(ISD::ADD, SL, IdxVT, NewBaseIdx, IdxOffset);
5026 
5027       SDValue Elt = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, NewEltVT,
5028                                 CastVec, TmpIdx);
5029       NewOps.push_back(Elt);
5030     }
5031 
5032     SDValue NewVec = DAG.getBuildVector(MidVT, SL, NewOps);
5033     Results.push_back(DAG.getNode(ISD::BITCAST, SL, EltVT, NewVec));
5034     break;
5035   }
5036   case ISD::INSERT_VECTOR_ELT: {
5037     MVT EltVT = OVT.getVectorElementType();
5038     MVT NewEltVT = NVT.getVectorElementType();
5039 
5040     // Handle bitcasts to a different vector type with the same total bit size
5041     //
5042     // e.g. v2i64 = insert_vector_elt x:v2i64, y:i64, z:i32
5043     //  =>
5044     //  v4i32:castx = bitcast x:v2i64
5045     //  v2i32:casty = bitcast y:i64
5046     //
5047     // v2i64 = bitcast
5048     //   (v4i32 insert_vector_elt
5049     //       (v4i32 insert_vector_elt v4i32:castx,
5050     //                                (extract_vector_elt casty, 0), 2 * z),
5051     //        (extract_vector_elt casty, 1), (2 * z + 1))
5052 
5053     assert(NVT.isVector() && OVT.getSizeInBits() == NVT.getSizeInBits() &&
5054            "Invalid promote type for insert_vector_elt");
5055     assert(NewEltVT.bitsLT(EltVT) && "not handled");
5056 
5057     MVT MidVT = getPromotedVectorElementType(TLI, EltVT, NewEltVT);
5058     unsigned NewEltsPerOldElt = MidVT.getVectorNumElements();
5059 
5060     SDValue Val = Node->getOperand(1);
5061     SDValue Idx = Node->getOperand(2);
5062     EVT IdxVT = Idx.getValueType();
5063     SDLoc SL(Node);
5064 
5065     SDValue Factor = DAG.getConstant(NewEltsPerOldElt, SDLoc(), IdxVT);
5066     SDValue NewBaseIdx = DAG.getNode(ISD::MUL, SL, IdxVT, Idx, Factor);
5067 
5068     SDValue CastVec = DAG.getNode(ISD::BITCAST, SL, NVT, Node->getOperand(0));
5069     SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, MidVT, Val);
5070 
5071     SDValue NewVec = CastVec;
5072     for (unsigned I = 0; I < NewEltsPerOldElt; ++I) {
5073       SDValue IdxOffset = DAG.getConstant(I, SL, IdxVT);
5074       SDValue InEltIdx = DAG.getNode(ISD::ADD, SL, IdxVT, NewBaseIdx, IdxOffset);
5075 
5076       SDValue Elt = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, NewEltVT,
5077                                 CastVal, IdxOffset);
5078 
5079       NewVec = DAG.getNode(ISD::INSERT_VECTOR_ELT, SL, NVT,
5080                            NewVec, Elt, InEltIdx);
5081     }
5082 
5083     Results.push_back(DAG.getNode(ISD::BITCAST, SL, OVT, NewVec));
5084     break;
5085   }
5086   case ISD::SCALAR_TO_VECTOR: {
5087     MVT EltVT = OVT.getVectorElementType();
5088     MVT NewEltVT = NVT.getVectorElementType();
5089 
5090     // Handle bitcasts to different vector type with the same total bit size.
5091     //
5092     // e.g. v2i64 = scalar_to_vector x:i64
5093     //   =>
5094     //  concat_vectors (v2i32 bitcast x:i64), (v2i32 undef)
5095     //
5096 
5097     MVT MidVT = getPromotedVectorElementType(TLI, EltVT, NewEltVT);
5098     SDValue Val = Node->getOperand(0);
5099     SDLoc SL(Node);
5100 
5101     SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, MidVT, Val);
5102     SDValue Undef = DAG.getUNDEF(MidVT);
5103 
5104     SmallVector<SDValue, 8> NewElts;
5105     NewElts.push_back(CastVal);
5106     for (unsigned I = 1, NElts = OVT.getVectorNumElements(); I != NElts; ++I)
5107       NewElts.push_back(Undef);
5108 
5109     SDValue Concat = DAG.getNode(ISD::CONCAT_VECTORS, SL, NVT, NewElts);
5110     SDValue CvtVec = DAG.getNode(ISD::BITCAST, SL, OVT, Concat);
5111     Results.push_back(CvtVec);
5112     break;
5113   }
5114   case ISD::ATOMIC_SWAP: {
5115     AtomicSDNode *AM = cast<AtomicSDNode>(Node);
5116     SDLoc SL(Node);
5117     SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, NVT, AM->getVal());
5118     assert(NVT.getSizeInBits() == OVT.getSizeInBits() &&
5119            "unexpected promotion type");
5120     assert(AM->getMemoryVT().getSizeInBits() == NVT.getSizeInBits() &&
5121            "unexpected atomic_swap with illegal type");
5122 
5123     SDValue NewAtomic
5124       = DAG.getAtomic(ISD::ATOMIC_SWAP, SL, NVT,
5125                       DAG.getVTList(NVT, MVT::Other),
5126                       { AM->getChain(), AM->getBasePtr(), CastVal },
5127                       AM->getMemOperand());
5128     Results.push_back(DAG.getNode(ISD::BITCAST, SL, OVT, NewAtomic));
5129     Results.push_back(NewAtomic.getValue(1));
5130     break;
5131   }
5132   }
5133 
5134   // Replace the original node with the legalized result.
5135   if (!Results.empty()) {
5136     LLVM_DEBUG(dbgs() << "Successfully promoted node\n");
5137     ReplaceNode(Node, Results.data());
5138   } else
5139     LLVM_DEBUG(dbgs() << "Could not promote node\n");
5140 }
5141 
5142 /// This is the entry point for the file.
5143 void SelectionDAG::Legalize() {
5144   AssignTopologicalOrder();
5145 
5146   SmallPtrSet<SDNode *, 16> LegalizedNodes;
5147   // Use a delete listener to remove nodes which were deleted during
5148   // legalization from LegalizeNodes. This is needed to handle the situation
5149   // where a new node is allocated by the object pool to the same address of a
5150   // previously deleted node.
5151   DAGNodeDeletedListener DeleteListener(
5152       *this,
5153       [&LegalizedNodes](SDNode *N, SDNode *E) { LegalizedNodes.erase(N); });
5154 
5155   SelectionDAGLegalize Legalizer(*this, LegalizedNodes);
5156 
5157   // Visit all the nodes. We start in topological order, so that we see
5158   // nodes with their original operands intact. Legalization can produce
5159   // new nodes which may themselves need to be legalized. Iterate until all
5160   // nodes have been legalized.
5161   while (true) {
5162     bool AnyLegalized = false;
5163     for (auto NI = allnodes_end(); NI != allnodes_begin();) {
5164       --NI;
5165 
5166       SDNode *N = &*NI;
5167       if (N->use_empty() && N != getRoot().getNode()) {
5168         ++NI;
5169         DeleteNode(N);
5170         continue;
5171       }
5172 
5173       if (LegalizedNodes.insert(N).second) {
5174         AnyLegalized = true;
5175         Legalizer.LegalizeOp(N);
5176 
5177         if (N->use_empty() && N != getRoot().getNode()) {
5178           ++NI;
5179           DeleteNode(N);
5180         }
5181       }
5182     }
5183     if (!AnyLegalized)
5184       break;
5185 
5186   }
5187 
5188   // Remove dead nodes now.
5189   RemoveDeadNodes();
5190 }
5191 
5192 bool SelectionDAG::LegalizeOp(SDNode *N,
5193                               SmallSetVector<SDNode *, 16> &UpdatedNodes) {
5194   SmallPtrSet<SDNode *, 16> LegalizedNodes;
5195   SelectionDAGLegalize Legalizer(*this, LegalizedNodes, &UpdatedNodes);
5196 
5197   // Directly insert the node in question, and legalize it. This will recurse
5198   // as needed through operands.
5199   LegalizedNodes.insert(N);
5200   Legalizer.LegalizeOp(N);
5201 
5202   return LegalizedNodes.count(N);
5203 }
5204