xref: /freebsd/contrib/llvm-project/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp (revision 770cf0a5f02dc8983a89c6568d741fbc25baa999)
1 //===- llvm/CodeGen/GlobalISel/IRTranslator.cpp - IRTranslator ---*- C++ -*-==//
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 /// \file
9 /// This file implements the IRTranslator class.
10 //===----------------------------------------------------------------------===//
11 
12 #include "llvm/CodeGen/GlobalISel/IRTranslator.h"
13 #include "llvm/ADT/PostOrderIterator.h"
14 #include "llvm/ADT/STLExtras.h"
15 #include "llvm/ADT/ScopeExit.h"
16 #include "llvm/ADT/SmallSet.h"
17 #include "llvm/ADT/SmallVector.h"
18 #include "llvm/Analysis/AliasAnalysis.h"
19 #include "llvm/Analysis/AssumptionCache.h"
20 #include "llvm/Analysis/BranchProbabilityInfo.h"
21 #include "llvm/Analysis/Loads.h"
22 #include "llvm/Analysis/OptimizationRemarkEmitter.h"
23 #include "llvm/Analysis/ValueTracking.h"
24 #include "llvm/Analysis/VectorUtils.h"
25 #include "llvm/CodeGen/Analysis.h"
26 #include "llvm/CodeGen/GlobalISel/CSEInfo.h"
27 #include "llvm/CodeGen/GlobalISel/CSEMIRBuilder.h"
28 #include "llvm/CodeGen/GlobalISel/CallLowering.h"
29 #include "llvm/CodeGen/GlobalISel/GISelChangeObserver.h"
30 #include "llvm/CodeGen/GlobalISel/InlineAsmLowering.h"
31 #include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
32 #include "llvm/CodeGen/LowLevelTypeUtils.h"
33 #include "llvm/CodeGen/MachineBasicBlock.h"
34 #include "llvm/CodeGen/MachineFrameInfo.h"
35 #include "llvm/CodeGen/MachineFunction.h"
36 #include "llvm/CodeGen/MachineInstrBuilder.h"
37 #include "llvm/CodeGen/MachineMemOperand.h"
38 #include "llvm/CodeGen/MachineModuleInfo.h"
39 #include "llvm/CodeGen/MachineOperand.h"
40 #include "llvm/CodeGen/MachineRegisterInfo.h"
41 #include "llvm/CodeGen/StackProtector.h"
42 #include "llvm/CodeGen/SwitchLoweringUtils.h"
43 #include "llvm/CodeGen/TargetFrameLowering.h"
44 #include "llvm/CodeGen/TargetInstrInfo.h"
45 #include "llvm/CodeGen/TargetLowering.h"
46 #include "llvm/CodeGen/TargetOpcodes.h"
47 #include "llvm/CodeGen/TargetPassConfig.h"
48 #include "llvm/CodeGen/TargetRegisterInfo.h"
49 #include "llvm/CodeGen/TargetSubtargetInfo.h"
50 #include "llvm/CodeGenTypes/LowLevelType.h"
51 #include "llvm/IR/BasicBlock.h"
52 #include "llvm/IR/CFG.h"
53 #include "llvm/IR/Constant.h"
54 #include "llvm/IR/Constants.h"
55 #include "llvm/IR/DataLayout.h"
56 #include "llvm/IR/DerivedTypes.h"
57 #include "llvm/IR/DiagnosticInfo.h"
58 #include "llvm/IR/Function.h"
59 #include "llvm/IR/GetElementPtrTypeIterator.h"
60 #include "llvm/IR/InlineAsm.h"
61 #include "llvm/IR/InstrTypes.h"
62 #include "llvm/IR/Instructions.h"
63 #include "llvm/IR/IntrinsicInst.h"
64 #include "llvm/IR/Intrinsics.h"
65 #include "llvm/IR/IntrinsicsAMDGPU.h"
66 #include "llvm/IR/LLVMContext.h"
67 #include "llvm/IR/Metadata.h"
68 #include "llvm/IR/PatternMatch.h"
69 #include "llvm/IR/Statepoint.h"
70 #include "llvm/IR/Type.h"
71 #include "llvm/IR/User.h"
72 #include "llvm/IR/Value.h"
73 #include "llvm/InitializePasses.h"
74 #include "llvm/MC/MCContext.h"
75 #include "llvm/Pass.h"
76 #include "llvm/Support/Casting.h"
77 #include "llvm/Support/CodeGen.h"
78 #include "llvm/Support/Debug.h"
79 #include "llvm/Support/ErrorHandling.h"
80 #include "llvm/Support/MathExtras.h"
81 #include "llvm/Support/raw_ostream.h"
82 #include "llvm/Target/TargetMachine.h"
83 #include "llvm/Transforms/Utils/Local.h"
84 #include "llvm/Transforms/Utils/MemoryOpRemark.h"
85 #include <algorithm>
86 #include <cassert>
87 #include <cstdint>
88 #include <iterator>
89 #include <optional>
90 #include <string>
91 #include <utility>
92 #include <vector>
93 
94 #define DEBUG_TYPE "irtranslator"
95 
96 using namespace llvm;
97 
98 static cl::opt<bool>
99     EnableCSEInIRTranslator("enable-cse-in-irtranslator",
100                             cl::desc("Should enable CSE in irtranslator"),
101                             cl::Optional, cl::init(false));
102 char IRTranslator::ID = 0;
103 
104 INITIALIZE_PASS_BEGIN(IRTranslator, DEBUG_TYPE, "IRTranslator LLVM IR -> MI",
105                 false, false)
106 INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
107 INITIALIZE_PASS_DEPENDENCY(GISelCSEAnalysisWrapperPass)
108 INITIALIZE_PASS_DEPENDENCY(BlockFrequencyInfoWrapperPass)
109 INITIALIZE_PASS_DEPENDENCY(StackProtector)
110 INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
111 INITIALIZE_PASS_END(IRTranslator, DEBUG_TYPE, "IRTranslator LLVM IR -> MI",
112                 false, false)
113 
114 static void reportTranslationError(MachineFunction &MF,
115                                    const TargetPassConfig &TPC,
116                                    OptimizationRemarkEmitter &ORE,
117                                    OptimizationRemarkMissed &R) {
118   MF.getProperties().setFailedISel();
119 
120   // Print the function name explicitly if we don't have a debug location (which
121   // makes the diagnostic less useful) or if we're going to emit a raw error.
122   if (!R.getLocation().isValid() || TPC.isGlobalISelAbortEnabled())
123     R << (" (in function: " + MF.getName() + ")").str();
124 
125   if (TPC.isGlobalISelAbortEnabled())
126     report_fatal_error(Twine(R.getMsg()));
127   else
128     ORE.emit(R);
129 }
130 
131 IRTranslator::IRTranslator(CodeGenOptLevel optlevel)
132     : MachineFunctionPass(ID), OptLevel(optlevel) {}
133 
134 #ifndef NDEBUG
135 namespace {
136 /// Verify that every instruction created has the same DILocation as the
137 /// instruction being translated.
138 class DILocationVerifier : public GISelChangeObserver {
139   const Instruction *CurrInst = nullptr;
140 
141 public:
142   DILocationVerifier() = default;
143   ~DILocationVerifier() = default;
144 
145   const Instruction *getCurrentInst() const { return CurrInst; }
146   void setCurrentInst(const Instruction *Inst) { CurrInst = Inst; }
147 
148   void erasingInstr(MachineInstr &MI) override {}
149   void changingInstr(MachineInstr &MI) override {}
150   void changedInstr(MachineInstr &MI) override {}
151 
152   void createdInstr(MachineInstr &MI) override {
153     assert(getCurrentInst() && "Inserted instruction without a current MI");
154 
155     // Only print the check message if we're actually checking it.
156 #ifndef NDEBUG
157     LLVM_DEBUG(dbgs() << "Checking DILocation from " << *CurrInst
158                       << " was copied to " << MI);
159 #endif
160     // We allow insts in the entry block to have no debug loc because
161     // they could have originated from constants, and we don't want a jumpy
162     // debug experience.
163     assert((CurrInst->getDebugLoc() == MI.getDebugLoc() ||
164             (MI.getParent()->isEntryBlock() && !MI.getDebugLoc()) ||
165             (MI.isDebugInstr())) &&
166            "Line info was not transferred to all instructions");
167   }
168 };
169 } // namespace
170 #endif // ifndef NDEBUG
171 
172 
173 void IRTranslator::getAnalysisUsage(AnalysisUsage &AU) const {
174   AU.addRequired<StackProtector>();
175   AU.addRequired<TargetPassConfig>();
176   AU.addRequired<GISelCSEAnalysisWrapperPass>();
177   AU.addRequired<AssumptionCacheTracker>();
178   if (OptLevel != CodeGenOptLevel::None) {
179     AU.addRequired<BranchProbabilityInfoWrapperPass>();
180     AU.addRequired<AAResultsWrapperPass>();
181   }
182   AU.addRequired<TargetLibraryInfoWrapperPass>();
183   AU.addPreserved<TargetLibraryInfoWrapperPass>();
184   getSelectionDAGFallbackAnalysisUsage(AU);
185   MachineFunctionPass::getAnalysisUsage(AU);
186 }
187 
188 IRTranslator::ValueToVRegInfo::VRegListT &
189 IRTranslator::allocateVRegs(const Value &Val) {
190   auto VRegsIt = VMap.findVRegs(Val);
191   if (VRegsIt != VMap.vregs_end())
192     return *VRegsIt->second;
193   auto *Regs = VMap.getVRegs(Val);
194   auto *Offsets = VMap.getOffsets(Val);
195   SmallVector<LLT, 4> SplitTys;
196   computeValueLLTs(*DL, *Val.getType(), SplitTys,
197                    Offsets->empty() ? Offsets : nullptr);
198   for (unsigned i = 0; i < SplitTys.size(); ++i)
199     Regs->push_back(0);
200   return *Regs;
201 }
202 
203 ArrayRef<Register> IRTranslator::getOrCreateVRegs(const Value &Val) {
204   auto VRegsIt = VMap.findVRegs(Val);
205   if (VRegsIt != VMap.vregs_end())
206     return *VRegsIt->second;
207 
208   if (Val.getType()->isVoidTy())
209     return *VMap.getVRegs(Val);
210 
211   // Create entry for this type.
212   auto *VRegs = VMap.getVRegs(Val);
213   auto *Offsets = VMap.getOffsets(Val);
214 
215   if (!Val.getType()->isTokenTy())
216     assert(Val.getType()->isSized() &&
217            "Don't know how to create an empty vreg");
218 
219   SmallVector<LLT, 4> SplitTys;
220   computeValueLLTs(*DL, *Val.getType(), SplitTys,
221                    Offsets->empty() ? Offsets : nullptr);
222 
223   if (!isa<Constant>(Val)) {
224     for (auto Ty : SplitTys)
225       VRegs->push_back(MRI->createGenericVirtualRegister(Ty));
226     return *VRegs;
227   }
228 
229   if (Val.getType()->isAggregateType()) {
230     // UndefValue, ConstantAggregateZero
231     auto &C = cast<Constant>(Val);
232     unsigned Idx = 0;
233     while (auto Elt = C.getAggregateElement(Idx++)) {
234       auto EltRegs = getOrCreateVRegs(*Elt);
235       llvm::append_range(*VRegs, EltRegs);
236     }
237   } else {
238     assert(SplitTys.size() == 1 && "unexpectedly split LLT");
239     VRegs->push_back(MRI->createGenericVirtualRegister(SplitTys[0]));
240     bool Success = translate(cast<Constant>(Val), VRegs->front());
241     if (!Success) {
242       OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
243                                  MF->getFunction().getSubprogram(),
244                                  &MF->getFunction().getEntryBlock());
245       R << "unable to translate constant: " << ore::NV("Type", Val.getType());
246       reportTranslationError(*MF, *TPC, *ORE, R);
247       return *VRegs;
248     }
249   }
250 
251   return *VRegs;
252 }
253 
254 int IRTranslator::getOrCreateFrameIndex(const AllocaInst &AI) {
255   auto [MapEntry, Inserted] = FrameIndices.try_emplace(&AI);
256   if (!Inserted)
257     return MapEntry->second;
258 
259   uint64_t ElementSize = DL->getTypeAllocSize(AI.getAllocatedType());
260   uint64_t Size =
261       ElementSize * cast<ConstantInt>(AI.getArraySize())->getZExtValue();
262 
263   // Always allocate at least one byte.
264   Size = std::max<uint64_t>(Size, 1u);
265 
266   int &FI = MapEntry->second;
267   FI = MF->getFrameInfo().CreateStackObject(Size, AI.getAlign(), false, &AI);
268   return FI;
269 }
270 
271 Align IRTranslator::getMemOpAlign(const Instruction &I) {
272   if (const StoreInst *SI = dyn_cast<StoreInst>(&I))
273     return SI->getAlign();
274   if (const LoadInst *LI = dyn_cast<LoadInst>(&I))
275     return LI->getAlign();
276   if (const AtomicCmpXchgInst *AI = dyn_cast<AtomicCmpXchgInst>(&I))
277     return AI->getAlign();
278   if (const AtomicRMWInst *AI = dyn_cast<AtomicRMWInst>(&I))
279     return AI->getAlign();
280 
281   OptimizationRemarkMissed R("gisel-irtranslator", "", &I);
282   R << "unable to translate memop: " << ore::NV("Opcode", &I);
283   reportTranslationError(*MF, *TPC, *ORE, R);
284   return Align(1);
285 }
286 
287 MachineBasicBlock &IRTranslator::getMBB(const BasicBlock &BB) {
288   MachineBasicBlock *MBB = FuncInfo.getMBB(&BB);
289   assert(MBB && "BasicBlock was not encountered before");
290   return *MBB;
291 }
292 
293 void IRTranslator::addMachineCFGPred(CFGEdge Edge, MachineBasicBlock *NewPred) {
294   assert(NewPred && "new predecessor must be a real MachineBasicBlock");
295   MachinePreds[Edge].push_back(NewPred);
296 }
297 
298 static bool containsBF16Type(const User &U) {
299   // BF16 cannot currently be represented by LLT, to avoid miscompiles we
300   // prevent any instructions using them. FIXME: This can be removed once LLT
301   // supports bfloat.
302   return U.getType()->getScalarType()->isBFloatTy() ||
303          any_of(U.operands(), [](Value *V) {
304            return V->getType()->getScalarType()->isBFloatTy();
305          });
306 }
307 
308 bool IRTranslator::translateBinaryOp(unsigned Opcode, const User &U,
309                                      MachineIRBuilder &MIRBuilder) {
310   if (containsBF16Type(U))
311     return false;
312 
313   // Get or create a virtual register for each value.
314   // Unless the value is a Constant => loadimm cst?
315   // or inline constant each time?
316   // Creation of a virtual register needs to have a size.
317   Register Op0 = getOrCreateVReg(*U.getOperand(0));
318   Register Op1 = getOrCreateVReg(*U.getOperand(1));
319   Register Res = getOrCreateVReg(U);
320   uint32_t Flags = 0;
321   if (isa<Instruction>(U)) {
322     const Instruction &I = cast<Instruction>(U);
323     Flags = MachineInstr::copyFlagsFromInstruction(I);
324   }
325 
326   MIRBuilder.buildInstr(Opcode, {Res}, {Op0, Op1}, Flags);
327   return true;
328 }
329 
330 bool IRTranslator::translateUnaryOp(unsigned Opcode, const User &U,
331                                     MachineIRBuilder &MIRBuilder) {
332   if (containsBF16Type(U))
333     return false;
334 
335   Register Op0 = getOrCreateVReg(*U.getOperand(0));
336   Register Res = getOrCreateVReg(U);
337   uint32_t Flags = 0;
338   if (isa<Instruction>(U)) {
339     const Instruction &I = cast<Instruction>(U);
340     Flags = MachineInstr::copyFlagsFromInstruction(I);
341   }
342   MIRBuilder.buildInstr(Opcode, {Res}, {Op0}, Flags);
343   return true;
344 }
345 
346 bool IRTranslator::translateFNeg(const User &U, MachineIRBuilder &MIRBuilder) {
347   return translateUnaryOp(TargetOpcode::G_FNEG, U, MIRBuilder);
348 }
349 
350 bool IRTranslator::translateCompare(const User &U,
351                                     MachineIRBuilder &MIRBuilder) {
352   if (containsBF16Type(U))
353     return false;
354 
355   auto *CI = cast<CmpInst>(&U);
356   Register Op0 = getOrCreateVReg(*U.getOperand(0));
357   Register Op1 = getOrCreateVReg(*U.getOperand(1));
358   Register Res = getOrCreateVReg(U);
359   CmpInst::Predicate Pred = CI->getPredicate();
360   uint32_t Flags = MachineInstr::copyFlagsFromInstruction(*CI);
361   if (CmpInst::isIntPredicate(Pred))
362     MIRBuilder.buildICmp(Pred, Res, Op0, Op1, Flags);
363   else if (Pred == CmpInst::FCMP_FALSE)
364     MIRBuilder.buildCopy(
365         Res, getOrCreateVReg(*Constant::getNullValue(U.getType())));
366   else if (Pred == CmpInst::FCMP_TRUE)
367     MIRBuilder.buildCopy(
368         Res, getOrCreateVReg(*Constant::getAllOnesValue(U.getType())));
369   else
370     MIRBuilder.buildFCmp(Pred, Res, Op0, Op1, Flags);
371 
372   return true;
373 }
374 
375 bool IRTranslator::translateRet(const User &U, MachineIRBuilder &MIRBuilder) {
376   const ReturnInst &RI = cast<ReturnInst>(U);
377   const Value *Ret = RI.getReturnValue();
378   if (Ret && DL->getTypeStoreSize(Ret->getType()).isZero())
379     Ret = nullptr;
380 
381   ArrayRef<Register> VRegs;
382   if (Ret)
383     VRegs = getOrCreateVRegs(*Ret);
384 
385   Register SwiftErrorVReg = 0;
386   if (CLI->supportSwiftError() && SwiftError.getFunctionArg()) {
387     SwiftErrorVReg = SwiftError.getOrCreateVRegUseAt(
388         &RI, &MIRBuilder.getMBB(), SwiftError.getFunctionArg());
389   }
390 
391   // The target may mess up with the insertion point, but
392   // this is not important as a return is the last instruction
393   // of the block anyway.
394   return CLI->lowerReturn(MIRBuilder, Ret, VRegs, FuncInfo, SwiftErrorVReg);
395 }
396 
397 void IRTranslator::emitBranchForMergedCondition(
398     const Value *Cond, MachineBasicBlock *TBB, MachineBasicBlock *FBB,
399     MachineBasicBlock *CurBB, MachineBasicBlock *SwitchBB,
400     BranchProbability TProb, BranchProbability FProb, bool InvertCond) {
401   // If the leaf of the tree is a comparison, merge the condition into
402   // the caseblock.
403   if (const CmpInst *BOp = dyn_cast<CmpInst>(Cond)) {
404     CmpInst::Predicate Condition;
405     if (const ICmpInst *IC = dyn_cast<ICmpInst>(Cond)) {
406       Condition = InvertCond ? IC->getInversePredicate() : IC->getPredicate();
407     } else {
408       const FCmpInst *FC = cast<FCmpInst>(Cond);
409       Condition = InvertCond ? FC->getInversePredicate() : FC->getPredicate();
410     }
411 
412     SwitchCG::CaseBlock CB(Condition, false, BOp->getOperand(0),
413                            BOp->getOperand(1), nullptr, TBB, FBB, CurBB,
414                            CurBuilder->getDebugLoc(), TProb, FProb);
415     SL->SwitchCases.push_back(CB);
416     return;
417   }
418 
419   // Create a CaseBlock record representing this branch.
420   CmpInst::Predicate Pred = InvertCond ? CmpInst::ICMP_NE : CmpInst::ICMP_EQ;
421   SwitchCG::CaseBlock CB(
422       Pred, false, Cond, ConstantInt::getTrue(MF->getFunction().getContext()),
423       nullptr, TBB, FBB, CurBB, CurBuilder->getDebugLoc(), TProb, FProb);
424   SL->SwitchCases.push_back(CB);
425 }
426 
427 static bool isValInBlock(const Value *V, const BasicBlock *BB) {
428   if (const Instruction *I = dyn_cast<Instruction>(V))
429     return I->getParent() == BB;
430   return true;
431 }
432 
433 void IRTranslator::findMergedConditions(
434     const Value *Cond, MachineBasicBlock *TBB, MachineBasicBlock *FBB,
435     MachineBasicBlock *CurBB, MachineBasicBlock *SwitchBB,
436     Instruction::BinaryOps Opc, BranchProbability TProb,
437     BranchProbability FProb, bool InvertCond) {
438   using namespace PatternMatch;
439   assert((Opc == Instruction::And || Opc == Instruction::Or) &&
440          "Expected Opc to be AND/OR");
441   // Skip over not part of the tree and remember to invert op and operands at
442   // next level.
443   Value *NotCond;
444   if (match(Cond, m_OneUse(m_Not(m_Value(NotCond)))) &&
445       isValInBlock(NotCond, CurBB->getBasicBlock())) {
446     findMergedConditions(NotCond, TBB, FBB, CurBB, SwitchBB, Opc, TProb, FProb,
447                          !InvertCond);
448     return;
449   }
450 
451   const Instruction *BOp = dyn_cast<Instruction>(Cond);
452   const Value *BOpOp0, *BOpOp1;
453   // Compute the effective opcode for Cond, taking into account whether it needs
454   // to be inverted, e.g.
455   //   and (not (or A, B)), C
456   // gets lowered as
457   //   and (and (not A, not B), C)
458   Instruction::BinaryOps BOpc = (Instruction::BinaryOps)0;
459   if (BOp) {
460     BOpc = match(BOp, m_LogicalAnd(m_Value(BOpOp0), m_Value(BOpOp1)))
461                ? Instruction::And
462                : (match(BOp, m_LogicalOr(m_Value(BOpOp0), m_Value(BOpOp1)))
463                       ? Instruction::Or
464                       : (Instruction::BinaryOps)0);
465     if (InvertCond) {
466       if (BOpc == Instruction::And)
467         BOpc = Instruction::Or;
468       else if (BOpc == Instruction::Or)
469         BOpc = Instruction::And;
470     }
471   }
472 
473   // If this node is not part of the or/and tree, emit it as a branch.
474   // Note that all nodes in the tree should have same opcode.
475   bool BOpIsInOrAndTree = BOpc && BOpc == Opc && BOp->hasOneUse();
476   if (!BOpIsInOrAndTree || BOp->getParent() != CurBB->getBasicBlock() ||
477       !isValInBlock(BOpOp0, CurBB->getBasicBlock()) ||
478       !isValInBlock(BOpOp1, CurBB->getBasicBlock())) {
479     emitBranchForMergedCondition(Cond, TBB, FBB, CurBB, SwitchBB, TProb, FProb,
480                                  InvertCond);
481     return;
482   }
483 
484   //  Create TmpBB after CurBB.
485   MachineFunction::iterator BBI(CurBB);
486   MachineBasicBlock *TmpBB =
487       MF->CreateMachineBasicBlock(CurBB->getBasicBlock());
488   CurBB->getParent()->insert(++BBI, TmpBB);
489 
490   if (Opc == Instruction::Or) {
491     // Codegen X | Y as:
492     // BB1:
493     //   jmp_if_X TBB
494     //   jmp TmpBB
495     // TmpBB:
496     //   jmp_if_Y TBB
497     //   jmp FBB
498     //
499 
500     // We have flexibility in setting Prob for BB1 and Prob for TmpBB.
501     // The requirement is that
502     //   TrueProb for BB1 + (FalseProb for BB1 * TrueProb for TmpBB)
503     //     = TrueProb for original BB.
504     // Assuming the original probabilities are A and B, one choice is to set
505     // BB1's probabilities to A/2 and A/2+B, and set TmpBB's probabilities to
506     // A/(1+B) and 2B/(1+B). This choice assumes that
507     //   TrueProb for BB1 == FalseProb for BB1 * TrueProb for TmpBB.
508     // Another choice is to assume TrueProb for BB1 equals to TrueProb for
509     // TmpBB, but the math is more complicated.
510 
511     auto NewTrueProb = TProb / 2;
512     auto NewFalseProb = TProb / 2 + FProb;
513     // Emit the LHS condition.
514     findMergedConditions(BOpOp0, TBB, TmpBB, CurBB, SwitchBB, Opc, NewTrueProb,
515                          NewFalseProb, InvertCond);
516 
517     // Normalize A/2 and B to get A/(1+B) and 2B/(1+B).
518     SmallVector<BranchProbability, 2> Probs{TProb / 2, FProb};
519     BranchProbability::normalizeProbabilities(Probs.begin(), Probs.end());
520     // Emit the RHS condition into TmpBB.
521     findMergedConditions(BOpOp1, TBB, FBB, TmpBB, SwitchBB, Opc, Probs[0],
522                          Probs[1], InvertCond);
523   } else {
524     assert(Opc == Instruction::And && "Unknown merge op!");
525     // Codegen X & Y as:
526     // BB1:
527     //   jmp_if_X TmpBB
528     //   jmp FBB
529     // TmpBB:
530     //   jmp_if_Y TBB
531     //   jmp FBB
532     //
533     //  This requires creation of TmpBB after CurBB.
534 
535     // We have flexibility in setting Prob for BB1 and Prob for TmpBB.
536     // The requirement is that
537     //   FalseProb for BB1 + (TrueProb for BB1 * FalseProb for TmpBB)
538     //     = FalseProb for original BB.
539     // Assuming the original probabilities are A and B, one choice is to set
540     // BB1's probabilities to A+B/2 and B/2, and set TmpBB's probabilities to
541     // 2A/(1+A) and B/(1+A). This choice assumes that FalseProb for BB1 ==
542     // TrueProb for BB1 * FalseProb for TmpBB.
543 
544     auto NewTrueProb = TProb + FProb / 2;
545     auto NewFalseProb = FProb / 2;
546     // Emit the LHS condition.
547     findMergedConditions(BOpOp0, TmpBB, FBB, CurBB, SwitchBB, Opc, NewTrueProb,
548                          NewFalseProb, InvertCond);
549 
550     // Normalize A and B/2 to get 2A/(1+A) and B/(1+A).
551     SmallVector<BranchProbability, 2> Probs{TProb, FProb / 2};
552     BranchProbability::normalizeProbabilities(Probs.begin(), Probs.end());
553     // Emit the RHS condition into TmpBB.
554     findMergedConditions(BOpOp1, TBB, FBB, TmpBB, SwitchBB, Opc, Probs[0],
555                          Probs[1], InvertCond);
556   }
557 }
558 
559 bool IRTranslator::shouldEmitAsBranches(
560     const std::vector<SwitchCG::CaseBlock> &Cases) {
561   // For multiple cases, it's better to emit as branches.
562   if (Cases.size() != 2)
563     return true;
564 
565   // If this is two comparisons of the same values or'd or and'd together, they
566   // will get folded into a single comparison, so don't emit two blocks.
567   if ((Cases[0].CmpLHS == Cases[1].CmpLHS &&
568        Cases[0].CmpRHS == Cases[1].CmpRHS) ||
569       (Cases[0].CmpRHS == Cases[1].CmpLHS &&
570        Cases[0].CmpLHS == Cases[1].CmpRHS)) {
571     return false;
572   }
573 
574   // Handle: (X != null) | (Y != null) --> (X|Y) != 0
575   // Handle: (X == null) & (Y == null) --> (X|Y) == 0
576   if (Cases[0].CmpRHS == Cases[1].CmpRHS &&
577       Cases[0].PredInfo.Pred == Cases[1].PredInfo.Pred &&
578       isa<Constant>(Cases[0].CmpRHS) &&
579       cast<Constant>(Cases[0].CmpRHS)->isNullValue()) {
580     if (Cases[0].PredInfo.Pred == CmpInst::ICMP_EQ &&
581         Cases[0].TrueBB == Cases[1].ThisBB)
582       return false;
583     if (Cases[0].PredInfo.Pred == CmpInst::ICMP_NE &&
584         Cases[0].FalseBB == Cases[1].ThisBB)
585       return false;
586   }
587 
588   return true;
589 }
590 
591 bool IRTranslator::translateBr(const User &U, MachineIRBuilder &MIRBuilder) {
592   const BranchInst &BrInst = cast<BranchInst>(U);
593   auto &CurMBB = MIRBuilder.getMBB();
594   auto *Succ0MBB = &getMBB(*BrInst.getSuccessor(0));
595 
596   if (BrInst.isUnconditional()) {
597     // If the unconditional target is the layout successor, fallthrough.
598     if (OptLevel == CodeGenOptLevel::None ||
599         !CurMBB.isLayoutSuccessor(Succ0MBB))
600       MIRBuilder.buildBr(*Succ0MBB);
601 
602     // Link successors.
603     for (const BasicBlock *Succ : successors(&BrInst))
604       CurMBB.addSuccessor(&getMBB(*Succ));
605     return true;
606   }
607 
608   // If this condition is one of the special cases we handle, do special stuff
609   // now.
610   const Value *CondVal = BrInst.getCondition();
611   MachineBasicBlock *Succ1MBB = &getMBB(*BrInst.getSuccessor(1));
612 
613   // If this is a series of conditions that are or'd or and'd together, emit
614   // this as a sequence of branches instead of setcc's with and/or operations.
615   // As long as jumps are not expensive (exceptions for multi-use logic ops,
616   // unpredictable branches, and vector extracts because those jumps are likely
617   // expensive for any target), this should improve performance.
618   // For example, instead of something like:
619   //     cmp A, B
620   //     C = seteq
621   //     cmp D, E
622   //     F = setle
623   //     or C, F
624   //     jnz foo
625   // Emit:
626   //     cmp A, B
627   //     je foo
628   //     cmp D, E
629   //     jle foo
630   using namespace PatternMatch;
631   const Instruction *CondI = dyn_cast<Instruction>(CondVal);
632   if (!TLI->isJumpExpensive() && CondI && CondI->hasOneUse() &&
633       !BrInst.hasMetadata(LLVMContext::MD_unpredictable)) {
634     Instruction::BinaryOps Opcode = (Instruction::BinaryOps)0;
635     Value *Vec;
636     const Value *BOp0, *BOp1;
637     if (match(CondI, m_LogicalAnd(m_Value(BOp0), m_Value(BOp1))))
638       Opcode = Instruction::And;
639     else if (match(CondI, m_LogicalOr(m_Value(BOp0), m_Value(BOp1))))
640       Opcode = Instruction::Or;
641 
642     if (Opcode && !(match(BOp0, m_ExtractElt(m_Value(Vec), m_Value())) &&
643                     match(BOp1, m_ExtractElt(m_Specific(Vec), m_Value())))) {
644       findMergedConditions(CondI, Succ0MBB, Succ1MBB, &CurMBB, &CurMBB, Opcode,
645                            getEdgeProbability(&CurMBB, Succ0MBB),
646                            getEdgeProbability(&CurMBB, Succ1MBB),
647                            /*InvertCond=*/false);
648       assert(SL->SwitchCases[0].ThisBB == &CurMBB && "Unexpected lowering!");
649 
650       // Allow some cases to be rejected.
651       if (shouldEmitAsBranches(SL->SwitchCases)) {
652         // Emit the branch for this block.
653         emitSwitchCase(SL->SwitchCases[0], &CurMBB, *CurBuilder);
654         SL->SwitchCases.erase(SL->SwitchCases.begin());
655         return true;
656       }
657 
658       // Okay, we decided not to do this, remove any inserted MBB's and clear
659       // SwitchCases.
660       for (unsigned I = 1, E = SL->SwitchCases.size(); I != E; ++I)
661         MF->erase(SL->SwitchCases[I].ThisBB);
662 
663       SL->SwitchCases.clear();
664     }
665   }
666 
667   // Create a CaseBlock record representing this branch.
668   SwitchCG::CaseBlock CB(CmpInst::ICMP_EQ, false, CondVal,
669                          ConstantInt::getTrue(MF->getFunction().getContext()),
670                          nullptr, Succ0MBB, Succ1MBB, &CurMBB,
671                          CurBuilder->getDebugLoc());
672 
673   // Use emitSwitchCase to actually insert the fast branch sequence for this
674   // cond branch.
675   emitSwitchCase(CB, &CurMBB, *CurBuilder);
676   return true;
677 }
678 
679 void IRTranslator::addSuccessorWithProb(MachineBasicBlock *Src,
680                                         MachineBasicBlock *Dst,
681                                         BranchProbability Prob) {
682   if (!FuncInfo.BPI) {
683     Src->addSuccessorWithoutProb(Dst);
684     return;
685   }
686   if (Prob.isUnknown())
687     Prob = getEdgeProbability(Src, Dst);
688   Src->addSuccessor(Dst, Prob);
689 }
690 
691 BranchProbability
692 IRTranslator::getEdgeProbability(const MachineBasicBlock *Src,
693                                  const MachineBasicBlock *Dst) const {
694   const BasicBlock *SrcBB = Src->getBasicBlock();
695   const BasicBlock *DstBB = Dst->getBasicBlock();
696   if (!FuncInfo.BPI) {
697     // If BPI is not available, set the default probability as 1 / N, where N is
698     // the number of successors.
699     auto SuccSize = std::max<uint32_t>(succ_size(SrcBB), 1);
700     return BranchProbability(1, SuccSize);
701   }
702   return FuncInfo.BPI->getEdgeProbability(SrcBB, DstBB);
703 }
704 
705 bool IRTranslator::translateSwitch(const User &U, MachineIRBuilder &MIB) {
706   using namespace SwitchCG;
707   // Extract cases from the switch.
708   const SwitchInst &SI = cast<SwitchInst>(U);
709   BranchProbabilityInfo *BPI = FuncInfo.BPI;
710   CaseClusterVector Clusters;
711   Clusters.reserve(SI.getNumCases());
712   for (const auto &I : SI.cases()) {
713     MachineBasicBlock *Succ = &getMBB(*I.getCaseSuccessor());
714     assert(Succ && "Could not find successor mbb in mapping");
715     const ConstantInt *CaseVal = I.getCaseValue();
716     BranchProbability Prob =
717         BPI ? BPI->getEdgeProbability(SI.getParent(), I.getSuccessorIndex())
718             : BranchProbability(1, SI.getNumCases() + 1);
719     Clusters.push_back(CaseCluster::range(CaseVal, CaseVal, Succ, Prob));
720   }
721 
722   MachineBasicBlock *DefaultMBB = &getMBB(*SI.getDefaultDest());
723 
724   // Cluster adjacent cases with the same destination. We do this at all
725   // optimization levels because it's cheap to do and will make codegen faster
726   // if there are many clusters.
727   sortAndRangeify(Clusters);
728 
729   MachineBasicBlock *SwitchMBB = &getMBB(*SI.getParent());
730 
731   // If there is only the default destination, jump there directly.
732   if (Clusters.empty()) {
733     SwitchMBB->addSuccessor(DefaultMBB);
734     if (DefaultMBB != SwitchMBB->getNextNode())
735       MIB.buildBr(*DefaultMBB);
736     return true;
737   }
738 
739   SL->findJumpTables(Clusters, &SI, std::nullopt, DefaultMBB, nullptr, nullptr);
740   SL->findBitTestClusters(Clusters, &SI);
741 
742   LLVM_DEBUG({
743     dbgs() << "Case clusters: ";
744     for (const CaseCluster &C : Clusters) {
745       if (C.Kind == CC_JumpTable)
746         dbgs() << "JT:";
747       if (C.Kind == CC_BitTests)
748         dbgs() << "BT:";
749 
750       C.Low->getValue().print(dbgs(), true);
751       if (C.Low != C.High) {
752         dbgs() << '-';
753         C.High->getValue().print(dbgs(), true);
754       }
755       dbgs() << ' ';
756     }
757     dbgs() << '\n';
758   });
759 
760   assert(!Clusters.empty());
761   SwitchWorkList WorkList;
762   CaseClusterIt First = Clusters.begin();
763   CaseClusterIt Last = Clusters.end() - 1;
764   auto DefaultProb = getEdgeProbability(SwitchMBB, DefaultMBB);
765   WorkList.push_back({SwitchMBB, First, Last, nullptr, nullptr, DefaultProb});
766 
767   while (!WorkList.empty()) {
768     SwitchWorkListItem W = WorkList.pop_back_val();
769 
770     unsigned NumClusters = W.LastCluster - W.FirstCluster + 1;
771     // For optimized builds, lower large range as a balanced binary tree.
772     if (NumClusters > 3 &&
773         MF->getTarget().getOptLevel() != CodeGenOptLevel::None &&
774         !DefaultMBB->getParent()->getFunction().hasMinSize()) {
775       splitWorkItem(WorkList, W, SI.getCondition(), SwitchMBB, MIB);
776       continue;
777     }
778 
779     if (!lowerSwitchWorkItem(W, SI.getCondition(), SwitchMBB, DefaultMBB, MIB))
780       return false;
781   }
782   return true;
783 }
784 
785 void IRTranslator::splitWorkItem(SwitchCG::SwitchWorkList &WorkList,
786                                  const SwitchCG::SwitchWorkListItem &W,
787                                  Value *Cond, MachineBasicBlock *SwitchMBB,
788                                  MachineIRBuilder &MIB) {
789   using namespace SwitchCG;
790   assert(W.FirstCluster->Low->getValue().slt(W.LastCluster->Low->getValue()) &&
791          "Clusters not sorted?");
792   assert(W.LastCluster - W.FirstCluster + 1 >= 2 && "Too small to split!");
793 
794   auto [LastLeft, FirstRight, LeftProb, RightProb] =
795       SL->computeSplitWorkItemInfo(W);
796 
797   // Use the first element on the right as pivot since we will make less-than
798   // comparisons against it.
799   CaseClusterIt PivotCluster = FirstRight;
800   assert(PivotCluster > W.FirstCluster);
801   assert(PivotCluster <= W.LastCluster);
802 
803   CaseClusterIt FirstLeft = W.FirstCluster;
804   CaseClusterIt LastRight = W.LastCluster;
805 
806   const ConstantInt *Pivot = PivotCluster->Low;
807 
808   // New blocks will be inserted immediately after the current one.
809   MachineFunction::iterator BBI(W.MBB);
810   ++BBI;
811 
812   // We will branch to the LHS if Value < Pivot. If LHS is a single cluster,
813   // we can branch to its destination directly if it's squeezed exactly in
814   // between the known lower bound and Pivot - 1.
815   MachineBasicBlock *LeftMBB;
816   if (FirstLeft == LastLeft && FirstLeft->Kind == CC_Range &&
817       FirstLeft->Low == W.GE &&
818       (FirstLeft->High->getValue() + 1LL) == Pivot->getValue()) {
819     LeftMBB = FirstLeft->MBB;
820   } else {
821     LeftMBB = FuncInfo.MF->CreateMachineBasicBlock(W.MBB->getBasicBlock());
822     FuncInfo.MF->insert(BBI, LeftMBB);
823     WorkList.push_back(
824         {LeftMBB, FirstLeft, LastLeft, W.GE, Pivot, W.DefaultProb / 2});
825   }
826 
827   // Similarly, we will branch to the RHS if Value >= Pivot. If RHS is a
828   // single cluster, RHS.Low == Pivot, and we can branch to its destination
829   // directly if RHS.High equals the current upper bound.
830   MachineBasicBlock *RightMBB;
831   if (FirstRight == LastRight && FirstRight->Kind == CC_Range && W.LT &&
832       (FirstRight->High->getValue() + 1ULL) == W.LT->getValue()) {
833     RightMBB = FirstRight->MBB;
834   } else {
835     RightMBB = FuncInfo.MF->CreateMachineBasicBlock(W.MBB->getBasicBlock());
836     FuncInfo.MF->insert(BBI, RightMBB);
837     WorkList.push_back(
838         {RightMBB, FirstRight, LastRight, Pivot, W.LT, W.DefaultProb / 2});
839   }
840 
841   // Create the CaseBlock record that will be used to lower the branch.
842   CaseBlock CB(ICmpInst::Predicate::ICMP_SLT, false, Cond, Pivot, nullptr,
843                LeftMBB, RightMBB, W.MBB, MIB.getDebugLoc(), LeftProb,
844                RightProb);
845 
846   if (W.MBB == SwitchMBB)
847     emitSwitchCase(CB, SwitchMBB, MIB);
848   else
849     SL->SwitchCases.push_back(CB);
850 }
851 
852 void IRTranslator::emitJumpTable(SwitchCG::JumpTable &JT,
853                                  MachineBasicBlock *MBB) {
854   // Emit the code for the jump table
855   assert(JT.Reg && "Should lower JT Header first!");
856   MachineIRBuilder MIB(*MBB->getParent());
857   MIB.setMBB(*MBB);
858   MIB.setDebugLoc(CurBuilder->getDebugLoc());
859 
860   Type *PtrIRTy = PointerType::getUnqual(MF->getFunction().getContext());
861   const LLT PtrTy = getLLTForType(*PtrIRTy, *DL);
862 
863   auto Table = MIB.buildJumpTable(PtrTy, JT.JTI);
864   MIB.buildBrJT(Table.getReg(0), JT.JTI, JT.Reg);
865 }
866 
867 bool IRTranslator::emitJumpTableHeader(SwitchCG::JumpTable &JT,
868                                        SwitchCG::JumpTableHeader &JTH,
869                                        MachineBasicBlock *HeaderBB) {
870   MachineIRBuilder MIB(*HeaderBB->getParent());
871   MIB.setMBB(*HeaderBB);
872   MIB.setDebugLoc(CurBuilder->getDebugLoc());
873 
874   const Value &SValue = *JTH.SValue;
875   // Subtract the lowest switch case value from the value being switched on.
876   const LLT SwitchTy = getLLTForType(*SValue.getType(), *DL);
877   Register SwitchOpReg = getOrCreateVReg(SValue);
878   auto FirstCst = MIB.buildConstant(SwitchTy, JTH.First);
879   auto Sub = MIB.buildSub({SwitchTy}, SwitchOpReg, FirstCst);
880 
881   // This value may be smaller or larger than the target's pointer type, and
882   // therefore require extension or truncating.
883   auto *PtrIRTy = PointerType::getUnqual(SValue.getContext());
884   const LLT PtrScalarTy = LLT::scalar(DL->getTypeSizeInBits(PtrIRTy));
885   Sub = MIB.buildZExtOrTrunc(PtrScalarTy, Sub);
886 
887   JT.Reg = Sub.getReg(0);
888 
889   if (JTH.FallthroughUnreachable) {
890     if (JT.MBB != HeaderBB->getNextNode())
891       MIB.buildBr(*JT.MBB);
892     return true;
893   }
894 
895   // Emit the range check for the jump table, and branch to the default block
896   // for the switch statement if the value being switched on exceeds the
897   // largest case in the switch.
898   auto Cst = getOrCreateVReg(
899       *ConstantInt::get(SValue.getType(), JTH.Last - JTH.First));
900   Cst = MIB.buildZExtOrTrunc(PtrScalarTy, Cst).getReg(0);
901   auto Cmp = MIB.buildICmp(CmpInst::ICMP_UGT, LLT::scalar(1), Sub, Cst);
902 
903   auto BrCond = MIB.buildBrCond(Cmp.getReg(0), *JT.Default);
904 
905   // Avoid emitting unnecessary branches to the next block.
906   if (JT.MBB != HeaderBB->getNextNode())
907     BrCond = MIB.buildBr(*JT.MBB);
908   return true;
909 }
910 
911 void IRTranslator::emitSwitchCase(SwitchCG::CaseBlock &CB,
912                                   MachineBasicBlock *SwitchBB,
913                                   MachineIRBuilder &MIB) {
914   Register CondLHS = getOrCreateVReg(*CB.CmpLHS);
915   Register Cond;
916   DebugLoc OldDbgLoc = MIB.getDebugLoc();
917   MIB.setDebugLoc(CB.DbgLoc);
918   MIB.setMBB(*CB.ThisBB);
919 
920   if (CB.PredInfo.NoCmp) {
921     // Branch or fall through to TrueBB.
922     addSuccessorWithProb(CB.ThisBB, CB.TrueBB, CB.TrueProb);
923     addMachineCFGPred({SwitchBB->getBasicBlock(), CB.TrueBB->getBasicBlock()},
924                       CB.ThisBB);
925     CB.ThisBB->normalizeSuccProbs();
926     if (CB.TrueBB != CB.ThisBB->getNextNode())
927       MIB.buildBr(*CB.TrueBB);
928     MIB.setDebugLoc(OldDbgLoc);
929     return;
930   }
931 
932   const LLT i1Ty = LLT::scalar(1);
933   // Build the compare.
934   if (!CB.CmpMHS) {
935     const auto *CI = dyn_cast<ConstantInt>(CB.CmpRHS);
936     // For conditional branch lowering, we might try to do something silly like
937     // emit an G_ICMP to compare an existing G_ICMP i1 result with true. If so,
938     // just re-use the existing condition vreg.
939     if (MRI->getType(CondLHS).getSizeInBits() == 1 && CI && CI->isOne() &&
940         CB.PredInfo.Pred == CmpInst::ICMP_EQ) {
941       Cond = CondLHS;
942     } else {
943       Register CondRHS = getOrCreateVReg(*CB.CmpRHS);
944       if (CmpInst::isFPPredicate(CB.PredInfo.Pred))
945         Cond =
946             MIB.buildFCmp(CB.PredInfo.Pred, i1Ty, CondLHS, CondRHS).getReg(0);
947       else
948         Cond =
949             MIB.buildICmp(CB.PredInfo.Pred, i1Ty, CondLHS, CondRHS).getReg(0);
950     }
951   } else {
952     assert(CB.PredInfo.Pred == CmpInst::ICMP_SLE &&
953            "Can only handle SLE ranges");
954 
955     const APInt& Low = cast<ConstantInt>(CB.CmpLHS)->getValue();
956     const APInt& High = cast<ConstantInt>(CB.CmpRHS)->getValue();
957 
958     Register CmpOpReg = getOrCreateVReg(*CB.CmpMHS);
959     if (cast<ConstantInt>(CB.CmpLHS)->isMinValue(true)) {
960       Register CondRHS = getOrCreateVReg(*CB.CmpRHS);
961       Cond =
962           MIB.buildICmp(CmpInst::ICMP_SLE, i1Ty, CmpOpReg, CondRHS).getReg(0);
963     } else {
964       const LLT CmpTy = MRI->getType(CmpOpReg);
965       auto Sub = MIB.buildSub({CmpTy}, CmpOpReg, CondLHS);
966       auto Diff = MIB.buildConstant(CmpTy, High - Low);
967       Cond = MIB.buildICmp(CmpInst::ICMP_ULE, i1Ty, Sub, Diff).getReg(0);
968     }
969   }
970 
971   // Update successor info
972   addSuccessorWithProb(CB.ThisBB, CB.TrueBB, CB.TrueProb);
973 
974   addMachineCFGPred({SwitchBB->getBasicBlock(), CB.TrueBB->getBasicBlock()},
975                     CB.ThisBB);
976 
977   // TrueBB and FalseBB are always different unless the incoming IR is
978   // degenerate. This only happens when running llc on weird IR.
979   if (CB.TrueBB != CB.FalseBB)
980     addSuccessorWithProb(CB.ThisBB, CB.FalseBB, CB.FalseProb);
981   CB.ThisBB->normalizeSuccProbs();
982 
983   addMachineCFGPred({SwitchBB->getBasicBlock(), CB.FalseBB->getBasicBlock()},
984                     CB.ThisBB);
985 
986   MIB.buildBrCond(Cond, *CB.TrueBB);
987   MIB.buildBr(*CB.FalseBB);
988   MIB.setDebugLoc(OldDbgLoc);
989 }
990 
991 bool IRTranslator::lowerJumpTableWorkItem(SwitchCG::SwitchWorkListItem W,
992                                           MachineBasicBlock *SwitchMBB,
993                                           MachineBasicBlock *CurMBB,
994                                           MachineBasicBlock *DefaultMBB,
995                                           MachineIRBuilder &MIB,
996                                           MachineFunction::iterator BBI,
997                                           BranchProbability UnhandledProbs,
998                                           SwitchCG::CaseClusterIt I,
999                                           MachineBasicBlock *Fallthrough,
1000                                           bool FallthroughUnreachable) {
1001   using namespace SwitchCG;
1002   MachineFunction *CurMF = SwitchMBB->getParent();
1003   // FIXME: Optimize away range check based on pivot comparisons.
1004   JumpTableHeader *JTH = &SL->JTCases[I->JTCasesIndex].first;
1005   SwitchCG::JumpTable *JT = &SL->JTCases[I->JTCasesIndex].second;
1006   BranchProbability DefaultProb = W.DefaultProb;
1007 
1008   // The jump block hasn't been inserted yet; insert it here.
1009   MachineBasicBlock *JumpMBB = JT->MBB;
1010   CurMF->insert(BBI, JumpMBB);
1011 
1012   // Since the jump table block is separate from the switch block, we need
1013   // to keep track of it as a machine predecessor to the default block,
1014   // otherwise we lose the phi edges.
1015   addMachineCFGPred({SwitchMBB->getBasicBlock(), DefaultMBB->getBasicBlock()},
1016                     CurMBB);
1017   addMachineCFGPred({SwitchMBB->getBasicBlock(), DefaultMBB->getBasicBlock()},
1018                     JumpMBB);
1019 
1020   auto JumpProb = I->Prob;
1021   auto FallthroughProb = UnhandledProbs;
1022 
1023   // If the default statement is a target of the jump table, we evenly
1024   // distribute the default probability to successors of CurMBB. Also
1025   // update the probability on the edge from JumpMBB to Fallthrough.
1026   for (MachineBasicBlock::succ_iterator SI = JumpMBB->succ_begin(),
1027                                         SE = JumpMBB->succ_end();
1028        SI != SE; ++SI) {
1029     if (*SI == DefaultMBB) {
1030       JumpProb += DefaultProb / 2;
1031       FallthroughProb -= DefaultProb / 2;
1032       JumpMBB->setSuccProbability(SI, DefaultProb / 2);
1033       JumpMBB->normalizeSuccProbs();
1034     } else {
1035       // Also record edges from the jump table block to it's successors.
1036       addMachineCFGPred({SwitchMBB->getBasicBlock(), (*SI)->getBasicBlock()},
1037                         JumpMBB);
1038     }
1039   }
1040 
1041   if (FallthroughUnreachable)
1042     JTH->FallthroughUnreachable = true;
1043 
1044   if (!JTH->FallthroughUnreachable)
1045     addSuccessorWithProb(CurMBB, Fallthrough, FallthroughProb);
1046   addSuccessorWithProb(CurMBB, JumpMBB, JumpProb);
1047   CurMBB->normalizeSuccProbs();
1048 
1049   // The jump table header will be inserted in our current block, do the
1050   // range check, and fall through to our fallthrough block.
1051   JTH->HeaderBB = CurMBB;
1052   JT->Default = Fallthrough; // FIXME: Move Default to JumpTableHeader.
1053 
1054   // If we're in the right place, emit the jump table header right now.
1055   if (CurMBB == SwitchMBB) {
1056     if (!emitJumpTableHeader(*JT, *JTH, CurMBB))
1057       return false;
1058     JTH->Emitted = true;
1059   }
1060   return true;
1061 }
1062 bool IRTranslator::lowerSwitchRangeWorkItem(SwitchCG::CaseClusterIt I,
1063                                             Value *Cond,
1064                                             MachineBasicBlock *Fallthrough,
1065                                             bool FallthroughUnreachable,
1066                                             BranchProbability UnhandledProbs,
1067                                             MachineBasicBlock *CurMBB,
1068                                             MachineIRBuilder &MIB,
1069                                             MachineBasicBlock *SwitchMBB) {
1070   using namespace SwitchCG;
1071   const Value *RHS, *LHS, *MHS;
1072   CmpInst::Predicate Pred;
1073   if (I->Low == I->High) {
1074     // Check Cond == I->Low.
1075     Pred = CmpInst::ICMP_EQ;
1076     LHS = Cond;
1077     RHS = I->Low;
1078     MHS = nullptr;
1079   } else {
1080     // Check I->Low <= Cond <= I->High.
1081     Pred = CmpInst::ICMP_SLE;
1082     LHS = I->Low;
1083     MHS = Cond;
1084     RHS = I->High;
1085   }
1086 
1087   // If Fallthrough is unreachable, fold away the comparison.
1088   // The false probability is the sum of all unhandled cases.
1089   CaseBlock CB(Pred, FallthroughUnreachable, LHS, RHS, MHS, I->MBB, Fallthrough,
1090                CurMBB, MIB.getDebugLoc(), I->Prob, UnhandledProbs);
1091 
1092   emitSwitchCase(CB, SwitchMBB, MIB);
1093   return true;
1094 }
1095 
1096 void IRTranslator::emitBitTestHeader(SwitchCG::BitTestBlock &B,
1097                                      MachineBasicBlock *SwitchBB) {
1098   MachineIRBuilder &MIB = *CurBuilder;
1099   MIB.setMBB(*SwitchBB);
1100 
1101   // Subtract the minimum value.
1102   Register SwitchOpReg = getOrCreateVReg(*B.SValue);
1103 
1104   LLT SwitchOpTy = MRI->getType(SwitchOpReg);
1105   Register MinValReg = MIB.buildConstant(SwitchOpTy, B.First).getReg(0);
1106   auto RangeSub = MIB.buildSub(SwitchOpTy, SwitchOpReg, MinValReg);
1107 
1108   Type *PtrIRTy = PointerType::getUnqual(MF->getFunction().getContext());
1109   const LLT PtrTy = getLLTForType(*PtrIRTy, *DL);
1110 
1111   LLT MaskTy = SwitchOpTy;
1112   if (MaskTy.getSizeInBits() > PtrTy.getSizeInBits() ||
1113       !llvm::has_single_bit<uint32_t>(MaskTy.getSizeInBits()))
1114     MaskTy = LLT::scalar(PtrTy.getSizeInBits());
1115   else {
1116     // Ensure that the type will fit the mask value.
1117     for (const SwitchCG::BitTestCase &Case : B.Cases) {
1118       if (!isUIntN(SwitchOpTy.getSizeInBits(), Case.Mask)) {
1119         // Switch table case range are encoded into series of masks.
1120         // Just use pointer type, it's guaranteed to fit.
1121         MaskTy = LLT::scalar(PtrTy.getSizeInBits());
1122         break;
1123       }
1124     }
1125   }
1126   Register SubReg = RangeSub.getReg(0);
1127   if (SwitchOpTy != MaskTy)
1128     SubReg = MIB.buildZExtOrTrunc(MaskTy, SubReg).getReg(0);
1129 
1130   B.RegVT = getMVTForLLT(MaskTy);
1131   B.Reg = SubReg;
1132 
1133   MachineBasicBlock *MBB = B.Cases[0].ThisBB;
1134 
1135   if (!B.FallthroughUnreachable)
1136     addSuccessorWithProb(SwitchBB, B.Default, B.DefaultProb);
1137   addSuccessorWithProb(SwitchBB, MBB, B.Prob);
1138 
1139   SwitchBB->normalizeSuccProbs();
1140 
1141   if (!B.FallthroughUnreachable) {
1142     // Conditional branch to the default block.
1143     auto RangeCst = MIB.buildConstant(SwitchOpTy, B.Range);
1144     auto RangeCmp = MIB.buildICmp(CmpInst::Predicate::ICMP_UGT, LLT::scalar(1),
1145                                   RangeSub, RangeCst);
1146     MIB.buildBrCond(RangeCmp, *B.Default);
1147   }
1148 
1149   // Avoid emitting unnecessary branches to the next block.
1150   if (MBB != SwitchBB->getNextNode())
1151     MIB.buildBr(*MBB);
1152 }
1153 
1154 void IRTranslator::emitBitTestCase(SwitchCG::BitTestBlock &BB,
1155                                    MachineBasicBlock *NextMBB,
1156                                    BranchProbability BranchProbToNext,
1157                                    Register Reg, SwitchCG::BitTestCase &B,
1158                                    MachineBasicBlock *SwitchBB) {
1159   MachineIRBuilder &MIB = *CurBuilder;
1160   MIB.setMBB(*SwitchBB);
1161 
1162   LLT SwitchTy = getLLTForMVT(BB.RegVT);
1163   Register Cmp;
1164   unsigned PopCount = llvm::popcount(B.Mask);
1165   if (PopCount == 1) {
1166     // Testing for a single bit; just compare the shift count with what it
1167     // would need to be to shift a 1 bit in that position.
1168     auto MaskTrailingZeros =
1169         MIB.buildConstant(SwitchTy, llvm::countr_zero(B.Mask));
1170     Cmp =
1171         MIB.buildICmp(ICmpInst::ICMP_EQ, LLT::scalar(1), Reg, MaskTrailingZeros)
1172             .getReg(0);
1173   } else if (PopCount == BB.Range) {
1174     // There is only one zero bit in the range, test for it directly.
1175     auto MaskTrailingOnes =
1176         MIB.buildConstant(SwitchTy, llvm::countr_one(B.Mask));
1177     Cmp = MIB.buildICmp(CmpInst::ICMP_NE, LLT::scalar(1), Reg, MaskTrailingOnes)
1178               .getReg(0);
1179   } else {
1180     // Make desired shift.
1181     auto CstOne = MIB.buildConstant(SwitchTy, 1);
1182     auto SwitchVal = MIB.buildShl(SwitchTy, CstOne, Reg);
1183 
1184     // Emit bit tests and jumps.
1185     auto CstMask = MIB.buildConstant(SwitchTy, B.Mask);
1186     auto AndOp = MIB.buildAnd(SwitchTy, SwitchVal, CstMask);
1187     auto CstZero = MIB.buildConstant(SwitchTy, 0);
1188     Cmp = MIB.buildICmp(CmpInst::ICMP_NE, LLT::scalar(1), AndOp, CstZero)
1189               .getReg(0);
1190   }
1191 
1192   // The branch probability from SwitchBB to B.TargetBB is B.ExtraProb.
1193   addSuccessorWithProb(SwitchBB, B.TargetBB, B.ExtraProb);
1194   // The branch probability from SwitchBB to NextMBB is BranchProbToNext.
1195   addSuccessorWithProb(SwitchBB, NextMBB, BranchProbToNext);
1196   // It is not guaranteed that the sum of B.ExtraProb and BranchProbToNext is
1197   // one as they are relative probabilities (and thus work more like weights),
1198   // and hence we need to normalize them to let the sum of them become one.
1199   SwitchBB->normalizeSuccProbs();
1200 
1201   // Record the fact that the IR edge from the header to the bit test target
1202   // will go through our new block. Neeeded for PHIs to have nodes added.
1203   addMachineCFGPred({BB.Parent->getBasicBlock(), B.TargetBB->getBasicBlock()},
1204                     SwitchBB);
1205 
1206   MIB.buildBrCond(Cmp, *B.TargetBB);
1207 
1208   // Avoid emitting unnecessary branches to the next block.
1209   if (NextMBB != SwitchBB->getNextNode())
1210     MIB.buildBr(*NextMBB);
1211 }
1212 
1213 bool IRTranslator::lowerBitTestWorkItem(
1214     SwitchCG::SwitchWorkListItem W, MachineBasicBlock *SwitchMBB,
1215     MachineBasicBlock *CurMBB, MachineBasicBlock *DefaultMBB,
1216     MachineIRBuilder &MIB, MachineFunction::iterator BBI,
1217     BranchProbability DefaultProb, BranchProbability UnhandledProbs,
1218     SwitchCG::CaseClusterIt I, MachineBasicBlock *Fallthrough,
1219     bool FallthroughUnreachable) {
1220   using namespace SwitchCG;
1221   MachineFunction *CurMF = SwitchMBB->getParent();
1222   // FIXME: Optimize away range check based on pivot comparisons.
1223   BitTestBlock *BTB = &SL->BitTestCases[I->BTCasesIndex];
1224   // The bit test blocks haven't been inserted yet; insert them here.
1225   for (BitTestCase &BTC : BTB->Cases)
1226     CurMF->insert(BBI, BTC.ThisBB);
1227 
1228   // Fill in fields of the BitTestBlock.
1229   BTB->Parent = CurMBB;
1230   BTB->Default = Fallthrough;
1231 
1232   BTB->DefaultProb = UnhandledProbs;
1233   // If the cases in bit test don't form a contiguous range, we evenly
1234   // distribute the probability on the edge to Fallthrough to two
1235   // successors of CurMBB.
1236   if (!BTB->ContiguousRange) {
1237     BTB->Prob += DefaultProb / 2;
1238     BTB->DefaultProb -= DefaultProb / 2;
1239   }
1240 
1241   if (FallthroughUnreachable)
1242     BTB->FallthroughUnreachable = true;
1243 
1244   // If we're in the right place, emit the bit test header right now.
1245   if (CurMBB == SwitchMBB) {
1246     emitBitTestHeader(*BTB, SwitchMBB);
1247     BTB->Emitted = true;
1248   }
1249   return true;
1250 }
1251 
1252 bool IRTranslator::lowerSwitchWorkItem(SwitchCG::SwitchWorkListItem W,
1253                                        Value *Cond,
1254                                        MachineBasicBlock *SwitchMBB,
1255                                        MachineBasicBlock *DefaultMBB,
1256                                        MachineIRBuilder &MIB) {
1257   using namespace SwitchCG;
1258   MachineFunction *CurMF = FuncInfo.MF;
1259   MachineBasicBlock *NextMBB = nullptr;
1260   MachineFunction::iterator BBI(W.MBB);
1261   if (++BBI != FuncInfo.MF->end())
1262     NextMBB = &*BBI;
1263 
1264   if (EnableOpts) {
1265     // Here, we order cases by probability so the most likely case will be
1266     // checked first. However, two clusters can have the same probability in
1267     // which case their relative ordering is non-deterministic. So we use Low
1268     // as a tie-breaker as clusters are guaranteed to never overlap.
1269     llvm::sort(W.FirstCluster, W.LastCluster + 1,
1270                [](const CaseCluster &a, const CaseCluster &b) {
1271                  return a.Prob != b.Prob
1272                             ? a.Prob > b.Prob
1273                             : a.Low->getValue().slt(b.Low->getValue());
1274                });
1275 
1276     // Rearrange the case blocks so that the last one falls through if possible
1277     // without changing the order of probabilities.
1278     for (CaseClusterIt I = W.LastCluster; I > W.FirstCluster;) {
1279       --I;
1280       if (I->Prob > W.LastCluster->Prob)
1281         break;
1282       if (I->Kind == CC_Range && I->MBB == NextMBB) {
1283         std::swap(*I, *W.LastCluster);
1284         break;
1285       }
1286     }
1287   }
1288 
1289   // Compute total probability.
1290   BranchProbability DefaultProb = W.DefaultProb;
1291   BranchProbability UnhandledProbs = DefaultProb;
1292   for (CaseClusterIt I = W.FirstCluster; I <= W.LastCluster; ++I)
1293     UnhandledProbs += I->Prob;
1294 
1295   MachineBasicBlock *CurMBB = W.MBB;
1296   for (CaseClusterIt I = W.FirstCluster, E = W.LastCluster; I <= E; ++I) {
1297     bool FallthroughUnreachable = false;
1298     MachineBasicBlock *Fallthrough;
1299     if (I == W.LastCluster) {
1300       // For the last cluster, fall through to the default destination.
1301       Fallthrough = DefaultMBB;
1302       FallthroughUnreachable = isa<UnreachableInst>(
1303           DefaultMBB->getBasicBlock()->getFirstNonPHIOrDbg());
1304     } else {
1305       Fallthrough = CurMF->CreateMachineBasicBlock(CurMBB->getBasicBlock());
1306       CurMF->insert(BBI, Fallthrough);
1307     }
1308     UnhandledProbs -= I->Prob;
1309 
1310     switch (I->Kind) {
1311     case CC_BitTests: {
1312       if (!lowerBitTestWorkItem(W, SwitchMBB, CurMBB, DefaultMBB, MIB, BBI,
1313                                 DefaultProb, UnhandledProbs, I, Fallthrough,
1314                                 FallthroughUnreachable)) {
1315         LLVM_DEBUG(dbgs() << "Failed to lower bit test for switch");
1316         return false;
1317       }
1318       break;
1319     }
1320 
1321     case CC_JumpTable: {
1322       if (!lowerJumpTableWorkItem(W, SwitchMBB, CurMBB, DefaultMBB, MIB, BBI,
1323                                   UnhandledProbs, I, Fallthrough,
1324                                   FallthroughUnreachable)) {
1325         LLVM_DEBUG(dbgs() << "Failed to lower jump table");
1326         return false;
1327       }
1328       break;
1329     }
1330     case CC_Range: {
1331       if (!lowerSwitchRangeWorkItem(I, Cond, Fallthrough,
1332                                     FallthroughUnreachable, UnhandledProbs,
1333                                     CurMBB, MIB, SwitchMBB)) {
1334         LLVM_DEBUG(dbgs() << "Failed to lower switch range");
1335         return false;
1336       }
1337       break;
1338     }
1339     }
1340     CurMBB = Fallthrough;
1341   }
1342 
1343   return true;
1344 }
1345 
1346 bool IRTranslator::translateIndirectBr(const User &U,
1347                                        MachineIRBuilder &MIRBuilder) {
1348   const IndirectBrInst &BrInst = cast<IndirectBrInst>(U);
1349 
1350   const Register Tgt = getOrCreateVReg(*BrInst.getAddress());
1351   MIRBuilder.buildBrIndirect(Tgt);
1352 
1353   // Link successors.
1354   SmallPtrSet<const BasicBlock *, 32> AddedSuccessors;
1355   MachineBasicBlock &CurBB = MIRBuilder.getMBB();
1356   for (const BasicBlock *Succ : successors(&BrInst)) {
1357     // It's legal for indirectbr instructions to have duplicate blocks in the
1358     // destination list. We don't allow this in MIR. Skip anything that's
1359     // already a successor.
1360     if (!AddedSuccessors.insert(Succ).second)
1361       continue;
1362     CurBB.addSuccessor(&getMBB(*Succ));
1363   }
1364 
1365   return true;
1366 }
1367 
1368 static bool isSwiftError(const Value *V) {
1369   if (auto Arg = dyn_cast<Argument>(V))
1370     return Arg->hasSwiftErrorAttr();
1371   if (auto AI = dyn_cast<AllocaInst>(V))
1372     return AI->isSwiftError();
1373   return false;
1374 }
1375 
1376 bool IRTranslator::translateLoad(const User &U, MachineIRBuilder &MIRBuilder) {
1377   const LoadInst &LI = cast<LoadInst>(U);
1378   TypeSize StoreSize = DL->getTypeStoreSize(LI.getType());
1379   if (StoreSize.isZero())
1380     return true;
1381 
1382   ArrayRef<Register> Regs = getOrCreateVRegs(LI);
1383   ArrayRef<uint64_t> Offsets = *VMap.getOffsets(LI);
1384   Register Base = getOrCreateVReg(*LI.getPointerOperand());
1385   AAMDNodes AAInfo = LI.getAAMetadata();
1386 
1387   const Value *Ptr = LI.getPointerOperand();
1388   Type *OffsetIRTy = DL->getIndexType(Ptr->getType());
1389   LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL);
1390 
1391   if (CLI->supportSwiftError() && isSwiftError(Ptr)) {
1392     assert(Regs.size() == 1 && "swifterror should be single pointer");
1393     Register VReg =
1394         SwiftError.getOrCreateVRegUseAt(&LI, &MIRBuilder.getMBB(), Ptr);
1395     MIRBuilder.buildCopy(Regs[0], VReg);
1396     return true;
1397   }
1398 
1399   MachineMemOperand::Flags Flags =
1400       TLI->getLoadMemOperandFlags(LI, *DL, AC, LibInfo);
1401   if (AA && !(Flags & MachineMemOperand::MOInvariant)) {
1402     if (AA->pointsToConstantMemory(
1403             MemoryLocation(Ptr, LocationSize::precise(StoreSize), AAInfo))) {
1404       Flags |= MachineMemOperand::MOInvariant;
1405     }
1406   }
1407 
1408   const MDNode *Ranges =
1409       Regs.size() == 1 ? LI.getMetadata(LLVMContext::MD_range) : nullptr;
1410   for (unsigned i = 0; i < Regs.size(); ++i) {
1411     Register Addr;
1412     MIRBuilder.materializePtrAdd(Addr, Base, OffsetTy, Offsets[i] / 8);
1413 
1414     MachinePointerInfo Ptr(LI.getPointerOperand(), Offsets[i] / 8);
1415     Align BaseAlign = getMemOpAlign(LI);
1416     auto MMO = MF->getMachineMemOperand(
1417         Ptr, Flags, MRI->getType(Regs[i]),
1418         commonAlignment(BaseAlign, Offsets[i] / 8), AAInfo, Ranges,
1419         LI.getSyncScopeID(), LI.getOrdering());
1420     MIRBuilder.buildLoad(Regs[i], Addr, *MMO);
1421   }
1422 
1423   return true;
1424 }
1425 
1426 bool IRTranslator::translateStore(const User &U, MachineIRBuilder &MIRBuilder) {
1427   const StoreInst &SI = cast<StoreInst>(U);
1428   if (DL->getTypeStoreSize(SI.getValueOperand()->getType()).isZero())
1429     return true;
1430 
1431   ArrayRef<Register> Vals = getOrCreateVRegs(*SI.getValueOperand());
1432   ArrayRef<uint64_t> Offsets = *VMap.getOffsets(*SI.getValueOperand());
1433   Register Base = getOrCreateVReg(*SI.getPointerOperand());
1434 
1435   Type *OffsetIRTy = DL->getIndexType(SI.getPointerOperandType());
1436   LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL);
1437 
1438   if (CLI->supportSwiftError() && isSwiftError(SI.getPointerOperand())) {
1439     assert(Vals.size() == 1 && "swifterror should be single pointer");
1440 
1441     Register VReg = SwiftError.getOrCreateVRegDefAt(&SI, &MIRBuilder.getMBB(),
1442                                                     SI.getPointerOperand());
1443     MIRBuilder.buildCopy(VReg, Vals[0]);
1444     return true;
1445   }
1446 
1447   MachineMemOperand::Flags Flags = TLI->getStoreMemOperandFlags(SI, *DL);
1448 
1449   for (unsigned i = 0; i < Vals.size(); ++i) {
1450     Register Addr;
1451     MIRBuilder.materializePtrAdd(Addr, Base, OffsetTy, Offsets[i] / 8);
1452 
1453     MachinePointerInfo Ptr(SI.getPointerOperand(), Offsets[i] / 8);
1454     Align BaseAlign = getMemOpAlign(SI);
1455     auto MMO = MF->getMachineMemOperand(
1456         Ptr, Flags, MRI->getType(Vals[i]),
1457         commonAlignment(BaseAlign, Offsets[i] / 8), SI.getAAMetadata(), nullptr,
1458         SI.getSyncScopeID(), SI.getOrdering());
1459     MIRBuilder.buildStore(Vals[i], Addr, *MMO);
1460   }
1461   return true;
1462 }
1463 
1464 static uint64_t getOffsetFromIndices(const User &U, const DataLayout &DL) {
1465   const Value *Src = U.getOperand(0);
1466   Type *Int32Ty = Type::getInt32Ty(U.getContext());
1467 
1468   // getIndexedOffsetInType is designed for GEPs, so the first index is the
1469   // usual array element rather than looking into the actual aggregate.
1470   SmallVector<Value *, 1> Indices;
1471   Indices.push_back(ConstantInt::get(Int32Ty, 0));
1472 
1473   if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(&U)) {
1474     for (auto Idx : EVI->indices())
1475       Indices.push_back(ConstantInt::get(Int32Ty, Idx));
1476   } else if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(&U)) {
1477     for (auto Idx : IVI->indices())
1478       Indices.push_back(ConstantInt::get(Int32Ty, Idx));
1479   } else {
1480     llvm::append_range(Indices, drop_begin(U.operands()));
1481   }
1482 
1483   return 8 * static_cast<uint64_t>(
1484                  DL.getIndexedOffsetInType(Src->getType(), Indices));
1485 }
1486 
1487 bool IRTranslator::translateExtractValue(const User &U,
1488                                          MachineIRBuilder &MIRBuilder) {
1489   const Value *Src = U.getOperand(0);
1490   uint64_t Offset = getOffsetFromIndices(U, *DL);
1491   ArrayRef<Register> SrcRegs = getOrCreateVRegs(*Src);
1492   ArrayRef<uint64_t> Offsets = *VMap.getOffsets(*Src);
1493   unsigned Idx = llvm::lower_bound(Offsets, Offset) - Offsets.begin();
1494   auto &DstRegs = allocateVRegs(U);
1495 
1496   for (unsigned i = 0; i < DstRegs.size(); ++i)
1497     DstRegs[i] = SrcRegs[Idx++];
1498 
1499   return true;
1500 }
1501 
1502 bool IRTranslator::translateInsertValue(const User &U,
1503                                         MachineIRBuilder &MIRBuilder) {
1504   const Value *Src = U.getOperand(0);
1505   uint64_t Offset = getOffsetFromIndices(U, *DL);
1506   auto &DstRegs = allocateVRegs(U);
1507   ArrayRef<uint64_t> DstOffsets = *VMap.getOffsets(U);
1508   ArrayRef<Register> SrcRegs = getOrCreateVRegs(*Src);
1509   ArrayRef<Register> InsertedRegs = getOrCreateVRegs(*U.getOperand(1));
1510   auto *InsertedIt = InsertedRegs.begin();
1511 
1512   for (unsigned i = 0; i < DstRegs.size(); ++i) {
1513     if (DstOffsets[i] >= Offset && InsertedIt != InsertedRegs.end())
1514       DstRegs[i] = *InsertedIt++;
1515     else
1516       DstRegs[i] = SrcRegs[i];
1517   }
1518 
1519   return true;
1520 }
1521 
1522 bool IRTranslator::translateSelect(const User &U,
1523                                    MachineIRBuilder &MIRBuilder) {
1524   Register Tst = getOrCreateVReg(*U.getOperand(0));
1525   ArrayRef<Register> ResRegs = getOrCreateVRegs(U);
1526   ArrayRef<Register> Op0Regs = getOrCreateVRegs(*U.getOperand(1));
1527   ArrayRef<Register> Op1Regs = getOrCreateVRegs(*U.getOperand(2));
1528 
1529   uint32_t Flags = 0;
1530   if (const SelectInst *SI = dyn_cast<SelectInst>(&U))
1531     Flags = MachineInstr::copyFlagsFromInstruction(*SI);
1532 
1533   for (unsigned i = 0; i < ResRegs.size(); ++i) {
1534     MIRBuilder.buildSelect(ResRegs[i], Tst, Op0Regs[i], Op1Regs[i], Flags);
1535   }
1536 
1537   return true;
1538 }
1539 
1540 bool IRTranslator::translateCopy(const User &U, const Value &V,
1541                                  MachineIRBuilder &MIRBuilder) {
1542   Register Src = getOrCreateVReg(V);
1543   auto &Regs = *VMap.getVRegs(U);
1544   if (Regs.empty()) {
1545     Regs.push_back(Src);
1546     VMap.getOffsets(U)->push_back(0);
1547   } else {
1548     // If we already assigned a vreg for this instruction, we can't change that.
1549     // Emit a copy to satisfy the users we already emitted.
1550     MIRBuilder.buildCopy(Regs[0], Src);
1551   }
1552   return true;
1553 }
1554 
1555 bool IRTranslator::translateBitCast(const User &U,
1556                                     MachineIRBuilder &MIRBuilder) {
1557   // If we're bitcasting to the source type, we can reuse the source vreg.
1558   if (getLLTForType(*U.getOperand(0)->getType(), *DL) ==
1559       getLLTForType(*U.getType(), *DL)) {
1560     // If the source is a ConstantInt then it was probably created by
1561     // ConstantHoisting and we should leave it alone.
1562     if (isa<ConstantInt>(U.getOperand(0)))
1563       return translateCast(TargetOpcode::G_CONSTANT_FOLD_BARRIER, U,
1564                            MIRBuilder);
1565     return translateCopy(U, *U.getOperand(0), MIRBuilder);
1566   }
1567 
1568   return translateCast(TargetOpcode::G_BITCAST, U, MIRBuilder);
1569 }
1570 
1571 bool IRTranslator::translateCast(unsigned Opcode, const User &U,
1572                                  MachineIRBuilder &MIRBuilder) {
1573   if (containsBF16Type(U))
1574     return false;
1575 
1576   uint32_t Flags = 0;
1577   if (const Instruction *I = dyn_cast<Instruction>(&U))
1578     Flags = MachineInstr::copyFlagsFromInstruction(*I);
1579 
1580   Register Op = getOrCreateVReg(*U.getOperand(0));
1581   Register Res = getOrCreateVReg(U);
1582   MIRBuilder.buildInstr(Opcode, {Res}, {Op}, Flags);
1583   return true;
1584 }
1585 
1586 bool IRTranslator::translateGetElementPtr(const User &U,
1587                                           MachineIRBuilder &MIRBuilder) {
1588   Value &Op0 = *U.getOperand(0);
1589   Register BaseReg = getOrCreateVReg(Op0);
1590   Type *PtrIRTy = Op0.getType();
1591   LLT PtrTy = getLLTForType(*PtrIRTy, *DL);
1592   Type *OffsetIRTy = DL->getIndexType(PtrIRTy);
1593   LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL);
1594 
1595   uint32_t Flags = 0;
1596   if (const Instruction *I = dyn_cast<Instruction>(&U))
1597     Flags = MachineInstr::copyFlagsFromInstruction(*I);
1598 
1599   // Normalize Vector GEP - all scalar operands should be converted to the
1600   // splat vector.
1601   unsigned VectorWidth = 0;
1602 
1603   // True if we should use a splat vector; using VectorWidth alone is not
1604   // sufficient.
1605   bool WantSplatVector = false;
1606   if (auto *VT = dyn_cast<VectorType>(U.getType())) {
1607     VectorWidth = cast<FixedVectorType>(VT)->getNumElements();
1608     // We don't produce 1 x N vectors; those are treated as scalars.
1609     WantSplatVector = VectorWidth > 1;
1610   }
1611 
1612   // We might need to splat the base pointer into a vector if the offsets
1613   // are vectors.
1614   if (WantSplatVector && !PtrTy.isVector()) {
1615     BaseReg = MIRBuilder
1616                   .buildSplatBuildVector(LLT::fixed_vector(VectorWidth, PtrTy),
1617                                          BaseReg)
1618                   .getReg(0);
1619     PtrIRTy = FixedVectorType::get(PtrIRTy, VectorWidth);
1620     PtrTy = getLLTForType(*PtrIRTy, *DL);
1621     OffsetIRTy = DL->getIndexType(PtrIRTy);
1622     OffsetTy = getLLTForType(*OffsetIRTy, *DL);
1623   }
1624 
1625   int64_t Offset = 0;
1626   for (gep_type_iterator GTI = gep_type_begin(&U), E = gep_type_end(&U);
1627        GTI != E; ++GTI) {
1628     const Value *Idx = GTI.getOperand();
1629     if (StructType *StTy = GTI.getStructTypeOrNull()) {
1630       unsigned Field = cast<Constant>(Idx)->getUniqueInteger().getZExtValue();
1631       Offset += DL->getStructLayout(StTy)->getElementOffset(Field);
1632       continue;
1633     } else {
1634       uint64_t ElementSize = GTI.getSequentialElementStride(*DL);
1635 
1636       // If this is a scalar constant or a splat vector of constants,
1637       // handle it quickly.
1638       if (const auto *CI = dyn_cast<ConstantInt>(Idx)) {
1639         if (std::optional<int64_t> Val = CI->getValue().trySExtValue()) {
1640           Offset += ElementSize * *Val;
1641           continue;
1642         }
1643       }
1644 
1645       if (Offset != 0) {
1646         auto OffsetMIB = MIRBuilder.buildConstant({OffsetTy}, Offset);
1647         BaseReg = MIRBuilder.buildPtrAdd(PtrTy, BaseReg, OffsetMIB.getReg(0))
1648                       .getReg(0);
1649         Offset = 0;
1650       }
1651 
1652       Register IdxReg = getOrCreateVReg(*Idx);
1653       LLT IdxTy = MRI->getType(IdxReg);
1654       if (IdxTy != OffsetTy) {
1655         if (!IdxTy.isVector() && WantSplatVector) {
1656           IdxReg = MIRBuilder
1657                        .buildSplatBuildVector(OffsetTy.changeElementType(IdxTy),
1658                                               IdxReg)
1659                        .getReg(0);
1660         }
1661 
1662         IdxReg = MIRBuilder.buildSExtOrTrunc(OffsetTy, IdxReg).getReg(0);
1663       }
1664 
1665       // N = N + Idx * ElementSize;
1666       // Avoid doing it for ElementSize of 1.
1667       Register GepOffsetReg;
1668       if (ElementSize != 1) {
1669         auto ElementSizeMIB = MIRBuilder.buildConstant(
1670             getLLTForType(*OffsetIRTy, *DL), ElementSize);
1671         GepOffsetReg =
1672             MIRBuilder.buildMul(OffsetTy, IdxReg, ElementSizeMIB).getReg(0);
1673       } else
1674         GepOffsetReg = IdxReg;
1675 
1676       BaseReg = MIRBuilder.buildPtrAdd(PtrTy, BaseReg, GepOffsetReg).getReg(0);
1677     }
1678   }
1679 
1680   if (Offset != 0) {
1681     auto OffsetMIB =
1682         MIRBuilder.buildConstant(OffsetTy, Offset);
1683 
1684     if (Offset >= 0 && cast<GEPOperator>(U).isInBounds())
1685       Flags |= MachineInstr::MIFlag::NoUWrap;
1686 
1687     MIRBuilder.buildPtrAdd(getOrCreateVReg(U), BaseReg, OffsetMIB.getReg(0),
1688                            Flags);
1689     return true;
1690   }
1691 
1692   MIRBuilder.buildCopy(getOrCreateVReg(U), BaseReg);
1693   return true;
1694 }
1695 
1696 bool IRTranslator::translateMemFunc(const CallInst &CI,
1697                                     MachineIRBuilder &MIRBuilder,
1698                                     unsigned Opcode) {
1699   const Value *SrcPtr = CI.getArgOperand(1);
1700   // If the source is undef, then just emit a nop.
1701   if (isa<UndefValue>(SrcPtr))
1702     return true;
1703 
1704   SmallVector<Register, 3> SrcRegs;
1705 
1706   unsigned MinPtrSize = UINT_MAX;
1707   for (auto AI = CI.arg_begin(), AE = CI.arg_end(); std::next(AI) != AE; ++AI) {
1708     Register SrcReg = getOrCreateVReg(**AI);
1709     LLT SrcTy = MRI->getType(SrcReg);
1710     if (SrcTy.isPointer())
1711       MinPtrSize = std::min<unsigned>(SrcTy.getSizeInBits(), MinPtrSize);
1712     SrcRegs.push_back(SrcReg);
1713   }
1714 
1715   LLT SizeTy = LLT::scalar(MinPtrSize);
1716 
1717   // The size operand should be the minimum of the pointer sizes.
1718   Register &SizeOpReg = SrcRegs[SrcRegs.size() - 1];
1719   if (MRI->getType(SizeOpReg) != SizeTy)
1720     SizeOpReg = MIRBuilder.buildZExtOrTrunc(SizeTy, SizeOpReg).getReg(0);
1721 
1722   auto ICall = MIRBuilder.buildInstr(Opcode);
1723   for (Register SrcReg : SrcRegs)
1724     ICall.addUse(SrcReg);
1725 
1726   Align DstAlign;
1727   Align SrcAlign;
1728   unsigned IsVol =
1729       cast<ConstantInt>(CI.getArgOperand(CI.arg_size() - 1))->getZExtValue();
1730 
1731   ConstantInt *CopySize = nullptr;
1732 
1733   if (auto *MCI = dyn_cast<MemCpyInst>(&CI)) {
1734     DstAlign = MCI->getDestAlign().valueOrOne();
1735     SrcAlign = MCI->getSourceAlign().valueOrOne();
1736     CopySize = dyn_cast<ConstantInt>(MCI->getArgOperand(2));
1737   } else if (auto *MMI = dyn_cast<MemMoveInst>(&CI)) {
1738     DstAlign = MMI->getDestAlign().valueOrOne();
1739     SrcAlign = MMI->getSourceAlign().valueOrOne();
1740     CopySize = dyn_cast<ConstantInt>(MMI->getArgOperand(2));
1741   } else {
1742     auto *MSI = cast<MemSetInst>(&CI);
1743     DstAlign = MSI->getDestAlign().valueOrOne();
1744   }
1745 
1746   if (Opcode != TargetOpcode::G_MEMCPY_INLINE) {
1747     // We need to propagate the tail call flag from the IR inst as an argument.
1748     // Otherwise, we have to pessimize and assume later that we cannot tail call
1749     // any memory intrinsics.
1750     ICall.addImm(CI.isTailCall() ? 1 : 0);
1751   }
1752 
1753   // Create mem operands to store the alignment and volatile info.
1754   MachineMemOperand::Flags LoadFlags = MachineMemOperand::MOLoad;
1755   MachineMemOperand::Flags StoreFlags = MachineMemOperand::MOStore;
1756   if (IsVol) {
1757     LoadFlags |= MachineMemOperand::MOVolatile;
1758     StoreFlags |= MachineMemOperand::MOVolatile;
1759   }
1760 
1761   AAMDNodes AAInfo = CI.getAAMetadata();
1762   if (AA && CopySize &&
1763       AA->pointsToConstantMemory(MemoryLocation(
1764           SrcPtr, LocationSize::precise(CopySize->getZExtValue()), AAInfo))) {
1765     LoadFlags |= MachineMemOperand::MOInvariant;
1766 
1767     // FIXME: pointsToConstantMemory probably does not imply dereferenceable,
1768     // but the previous usage implied it did. Probably should check
1769     // isDereferenceableAndAlignedPointer.
1770     LoadFlags |= MachineMemOperand::MODereferenceable;
1771   }
1772 
1773   ICall.addMemOperand(
1774       MF->getMachineMemOperand(MachinePointerInfo(CI.getArgOperand(0)),
1775                                StoreFlags, 1, DstAlign, AAInfo));
1776   if (Opcode != TargetOpcode::G_MEMSET)
1777     ICall.addMemOperand(MF->getMachineMemOperand(
1778         MachinePointerInfo(SrcPtr), LoadFlags, 1, SrcAlign, AAInfo));
1779 
1780   return true;
1781 }
1782 
1783 bool IRTranslator::translateTrap(const CallInst &CI,
1784                                  MachineIRBuilder &MIRBuilder,
1785                                  unsigned Opcode) {
1786   StringRef TrapFuncName =
1787       CI.getAttributes().getFnAttr("trap-func-name").getValueAsString();
1788   if (TrapFuncName.empty()) {
1789     if (Opcode == TargetOpcode::G_UBSANTRAP) {
1790       uint64_t Code = cast<ConstantInt>(CI.getOperand(0))->getZExtValue();
1791       MIRBuilder.buildInstr(Opcode, {}, ArrayRef<llvm::SrcOp>{Code});
1792     } else {
1793       MIRBuilder.buildInstr(Opcode);
1794     }
1795     return true;
1796   }
1797 
1798   CallLowering::CallLoweringInfo Info;
1799   if (Opcode == TargetOpcode::G_UBSANTRAP)
1800     Info.OrigArgs.push_back({getOrCreateVRegs(*CI.getArgOperand(0)),
1801                              CI.getArgOperand(0)->getType(), 0});
1802 
1803   Info.Callee = MachineOperand::CreateES(TrapFuncName.data());
1804   Info.CB = &CI;
1805   Info.OrigRet = {Register(), Type::getVoidTy(CI.getContext()), 0};
1806   return CLI->lowerCall(MIRBuilder, Info);
1807 }
1808 
1809 bool IRTranslator::translateVectorInterleave2Intrinsic(
1810     const CallInst &CI, MachineIRBuilder &MIRBuilder) {
1811   assert(CI.getIntrinsicID() == Intrinsic::vector_interleave2 &&
1812          "This function can only be called on the interleave2 intrinsic!");
1813   // Canonicalize interleave2 to G_SHUFFLE_VECTOR (similar to SelectionDAG).
1814   Register Op0 = getOrCreateVReg(*CI.getOperand(0));
1815   Register Op1 = getOrCreateVReg(*CI.getOperand(1));
1816   Register Res = getOrCreateVReg(CI);
1817 
1818   LLT OpTy = MRI->getType(Op0);
1819   MIRBuilder.buildShuffleVector(Res, Op0, Op1,
1820                                 createInterleaveMask(OpTy.getNumElements(), 2));
1821 
1822   return true;
1823 }
1824 
1825 bool IRTranslator::translateVectorDeinterleave2Intrinsic(
1826     const CallInst &CI, MachineIRBuilder &MIRBuilder) {
1827   assert(CI.getIntrinsicID() == Intrinsic::vector_deinterleave2 &&
1828          "This function can only be called on the deinterleave2 intrinsic!");
1829   // Canonicalize deinterleave2 to shuffles that extract sub-vectors (similar to
1830   // SelectionDAG).
1831   Register Op = getOrCreateVReg(*CI.getOperand(0));
1832   auto Undef = MIRBuilder.buildUndef(MRI->getType(Op));
1833   ArrayRef<Register> Res = getOrCreateVRegs(CI);
1834 
1835   LLT ResTy = MRI->getType(Res[0]);
1836   MIRBuilder.buildShuffleVector(Res[0], Op, Undef,
1837                                 createStrideMask(0, 2, ResTy.getNumElements()));
1838   MIRBuilder.buildShuffleVector(Res[1], Op, Undef,
1839                                 createStrideMask(1, 2, ResTy.getNumElements()));
1840 
1841   return true;
1842 }
1843 
1844 void IRTranslator::getStackGuard(Register DstReg,
1845                                  MachineIRBuilder &MIRBuilder) {
1846   const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo();
1847   MRI->setRegClass(DstReg, TRI->getPointerRegClass(*MF));
1848   auto MIB =
1849       MIRBuilder.buildInstr(TargetOpcode::LOAD_STACK_GUARD, {DstReg}, {});
1850 
1851   Value *Global = TLI->getSDagStackGuard(*MF->getFunction().getParent());
1852   if (!Global)
1853     return;
1854 
1855   unsigned AddrSpace = Global->getType()->getPointerAddressSpace();
1856   LLT PtrTy = LLT::pointer(AddrSpace, DL->getPointerSizeInBits(AddrSpace));
1857 
1858   MachinePointerInfo MPInfo(Global);
1859   auto Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOInvariant |
1860                MachineMemOperand::MODereferenceable;
1861   MachineMemOperand *MemRef = MF->getMachineMemOperand(
1862       MPInfo, Flags, PtrTy, DL->getPointerABIAlignment(AddrSpace));
1863   MIB.setMemRefs({MemRef});
1864 }
1865 
1866 bool IRTranslator::translateOverflowIntrinsic(const CallInst &CI, unsigned Op,
1867                                               MachineIRBuilder &MIRBuilder) {
1868   ArrayRef<Register> ResRegs = getOrCreateVRegs(CI);
1869   MIRBuilder.buildInstr(
1870       Op, {ResRegs[0], ResRegs[1]},
1871       {getOrCreateVReg(*CI.getOperand(0)), getOrCreateVReg(*CI.getOperand(1))});
1872 
1873   return true;
1874 }
1875 
1876 bool IRTranslator::translateFixedPointIntrinsic(unsigned Op, const CallInst &CI,
1877                                                 MachineIRBuilder &MIRBuilder) {
1878   Register Dst = getOrCreateVReg(CI);
1879   Register Src0 = getOrCreateVReg(*CI.getOperand(0));
1880   Register Src1 = getOrCreateVReg(*CI.getOperand(1));
1881   uint64_t Scale = cast<ConstantInt>(CI.getOperand(2))->getZExtValue();
1882   MIRBuilder.buildInstr(Op, {Dst}, { Src0, Src1, Scale });
1883   return true;
1884 }
1885 
1886 unsigned IRTranslator::getSimpleIntrinsicOpcode(Intrinsic::ID ID) {
1887   switch (ID) {
1888     default:
1889       break;
1890     case Intrinsic::acos:
1891       return TargetOpcode::G_FACOS;
1892     case Intrinsic::asin:
1893       return TargetOpcode::G_FASIN;
1894     case Intrinsic::atan:
1895       return TargetOpcode::G_FATAN;
1896     case Intrinsic::atan2:
1897       return TargetOpcode::G_FATAN2;
1898     case Intrinsic::bswap:
1899       return TargetOpcode::G_BSWAP;
1900     case Intrinsic::bitreverse:
1901       return TargetOpcode::G_BITREVERSE;
1902     case Intrinsic::fshl:
1903       return TargetOpcode::G_FSHL;
1904     case Intrinsic::fshr:
1905       return TargetOpcode::G_FSHR;
1906     case Intrinsic::ceil:
1907       return TargetOpcode::G_FCEIL;
1908     case Intrinsic::cos:
1909       return TargetOpcode::G_FCOS;
1910     case Intrinsic::cosh:
1911       return TargetOpcode::G_FCOSH;
1912     case Intrinsic::ctpop:
1913       return TargetOpcode::G_CTPOP;
1914     case Intrinsic::exp:
1915       return TargetOpcode::G_FEXP;
1916     case Intrinsic::exp2:
1917       return TargetOpcode::G_FEXP2;
1918     case Intrinsic::exp10:
1919       return TargetOpcode::G_FEXP10;
1920     case Intrinsic::fabs:
1921       return TargetOpcode::G_FABS;
1922     case Intrinsic::copysign:
1923       return TargetOpcode::G_FCOPYSIGN;
1924     case Intrinsic::minnum:
1925       return TargetOpcode::G_FMINNUM;
1926     case Intrinsic::maxnum:
1927       return TargetOpcode::G_FMAXNUM;
1928     case Intrinsic::minimum:
1929       return TargetOpcode::G_FMINIMUM;
1930     case Intrinsic::maximum:
1931       return TargetOpcode::G_FMAXIMUM;
1932     case Intrinsic::minimumnum:
1933       return TargetOpcode::G_FMINIMUMNUM;
1934     case Intrinsic::maximumnum:
1935       return TargetOpcode::G_FMAXIMUMNUM;
1936     case Intrinsic::canonicalize:
1937       return TargetOpcode::G_FCANONICALIZE;
1938     case Intrinsic::floor:
1939       return TargetOpcode::G_FFLOOR;
1940     case Intrinsic::fma:
1941       return TargetOpcode::G_FMA;
1942     case Intrinsic::log:
1943       return TargetOpcode::G_FLOG;
1944     case Intrinsic::log2:
1945       return TargetOpcode::G_FLOG2;
1946     case Intrinsic::log10:
1947       return TargetOpcode::G_FLOG10;
1948     case Intrinsic::ldexp:
1949       return TargetOpcode::G_FLDEXP;
1950     case Intrinsic::nearbyint:
1951       return TargetOpcode::G_FNEARBYINT;
1952     case Intrinsic::pow:
1953       return TargetOpcode::G_FPOW;
1954     case Intrinsic::powi:
1955       return TargetOpcode::G_FPOWI;
1956     case Intrinsic::rint:
1957       return TargetOpcode::G_FRINT;
1958     case Intrinsic::round:
1959       return TargetOpcode::G_INTRINSIC_ROUND;
1960     case Intrinsic::roundeven:
1961       return TargetOpcode::G_INTRINSIC_ROUNDEVEN;
1962     case Intrinsic::sin:
1963       return TargetOpcode::G_FSIN;
1964     case Intrinsic::sinh:
1965       return TargetOpcode::G_FSINH;
1966     case Intrinsic::sqrt:
1967       return TargetOpcode::G_FSQRT;
1968     case Intrinsic::tan:
1969       return TargetOpcode::G_FTAN;
1970     case Intrinsic::tanh:
1971       return TargetOpcode::G_FTANH;
1972     case Intrinsic::trunc:
1973       return TargetOpcode::G_INTRINSIC_TRUNC;
1974     case Intrinsic::readcyclecounter:
1975       return TargetOpcode::G_READCYCLECOUNTER;
1976     case Intrinsic::readsteadycounter:
1977       return TargetOpcode::G_READSTEADYCOUNTER;
1978     case Intrinsic::ptrmask:
1979       return TargetOpcode::G_PTRMASK;
1980     case Intrinsic::lrint:
1981       return TargetOpcode::G_INTRINSIC_LRINT;
1982     case Intrinsic::llrint:
1983       return TargetOpcode::G_INTRINSIC_LLRINT;
1984     // FADD/FMUL require checking the FMF, so are handled elsewhere.
1985     case Intrinsic::vector_reduce_fmin:
1986       return TargetOpcode::G_VECREDUCE_FMIN;
1987     case Intrinsic::vector_reduce_fmax:
1988       return TargetOpcode::G_VECREDUCE_FMAX;
1989     case Intrinsic::vector_reduce_fminimum:
1990       return TargetOpcode::G_VECREDUCE_FMINIMUM;
1991     case Intrinsic::vector_reduce_fmaximum:
1992       return TargetOpcode::G_VECREDUCE_FMAXIMUM;
1993     case Intrinsic::vector_reduce_add:
1994       return TargetOpcode::G_VECREDUCE_ADD;
1995     case Intrinsic::vector_reduce_mul:
1996       return TargetOpcode::G_VECREDUCE_MUL;
1997     case Intrinsic::vector_reduce_and:
1998       return TargetOpcode::G_VECREDUCE_AND;
1999     case Intrinsic::vector_reduce_or:
2000       return TargetOpcode::G_VECREDUCE_OR;
2001     case Intrinsic::vector_reduce_xor:
2002       return TargetOpcode::G_VECREDUCE_XOR;
2003     case Intrinsic::vector_reduce_smax:
2004       return TargetOpcode::G_VECREDUCE_SMAX;
2005     case Intrinsic::vector_reduce_smin:
2006       return TargetOpcode::G_VECREDUCE_SMIN;
2007     case Intrinsic::vector_reduce_umax:
2008       return TargetOpcode::G_VECREDUCE_UMAX;
2009     case Intrinsic::vector_reduce_umin:
2010       return TargetOpcode::G_VECREDUCE_UMIN;
2011     case Intrinsic::experimental_vector_compress:
2012       return TargetOpcode::G_VECTOR_COMPRESS;
2013     case Intrinsic::lround:
2014       return TargetOpcode::G_LROUND;
2015     case Intrinsic::llround:
2016       return TargetOpcode::G_LLROUND;
2017     case Intrinsic::get_fpenv:
2018       return TargetOpcode::G_GET_FPENV;
2019     case Intrinsic::get_fpmode:
2020       return TargetOpcode::G_GET_FPMODE;
2021   }
2022   return Intrinsic::not_intrinsic;
2023 }
2024 
2025 bool IRTranslator::translateSimpleIntrinsic(const CallInst &CI,
2026                                             Intrinsic::ID ID,
2027                                             MachineIRBuilder &MIRBuilder) {
2028 
2029   unsigned Op = getSimpleIntrinsicOpcode(ID);
2030 
2031   // Is this a simple intrinsic?
2032   if (Op == Intrinsic::not_intrinsic)
2033     return false;
2034 
2035   // Yes. Let's translate it.
2036   SmallVector<llvm::SrcOp, 4> VRegs;
2037   for (const auto &Arg : CI.args())
2038     VRegs.push_back(getOrCreateVReg(*Arg));
2039 
2040   MIRBuilder.buildInstr(Op, {getOrCreateVReg(CI)}, VRegs,
2041                         MachineInstr::copyFlagsFromInstruction(CI));
2042   return true;
2043 }
2044 
2045 // TODO: Include ConstainedOps.def when all strict instructions are defined.
2046 static unsigned getConstrainedOpcode(Intrinsic::ID ID) {
2047   switch (ID) {
2048   case Intrinsic::experimental_constrained_fadd:
2049     return TargetOpcode::G_STRICT_FADD;
2050   case Intrinsic::experimental_constrained_fsub:
2051     return TargetOpcode::G_STRICT_FSUB;
2052   case Intrinsic::experimental_constrained_fmul:
2053     return TargetOpcode::G_STRICT_FMUL;
2054   case Intrinsic::experimental_constrained_fdiv:
2055     return TargetOpcode::G_STRICT_FDIV;
2056   case Intrinsic::experimental_constrained_frem:
2057     return TargetOpcode::G_STRICT_FREM;
2058   case Intrinsic::experimental_constrained_fma:
2059     return TargetOpcode::G_STRICT_FMA;
2060   case Intrinsic::experimental_constrained_sqrt:
2061     return TargetOpcode::G_STRICT_FSQRT;
2062   case Intrinsic::experimental_constrained_ldexp:
2063     return TargetOpcode::G_STRICT_FLDEXP;
2064   default:
2065     return 0;
2066   }
2067 }
2068 
2069 bool IRTranslator::translateConstrainedFPIntrinsic(
2070   const ConstrainedFPIntrinsic &FPI, MachineIRBuilder &MIRBuilder) {
2071   fp::ExceptionBehavior EB = *FPI.getExceptionBehavior();
2072 
2073   unsigned Opcode = getConstrainedOpcode(FPI.getIntrinsicID());
2074   if (!Opcode)
2075     return false;
2076 
2077   uint32_t Flags = MachineInstr::copyFlagsFromInstruction(FPI);
2078   if (EB == fp::ExceptionBehavior::ebIgnore)
2079     Flags |= MachineInstr::NoFPExcept;
2080 
2081   SmallVector<llvm::SrcOp, 4> VRegs;
2082   for (unsigned I = 0, E = FPI.getNonMetadataArgCount(); I != E; ++I)
2083     VRegs.push_back(getOrCreateVReg(*FPI.getArgOperand(I)));
2084 
2085   MIRBuilder.buildInstr(Opcode, {getOrCreateVReg(FPI)}, VRegs, Flags);
2086   return true;
2087 }
2088 
2089 std::optional<MCRegister> IRTranslator::getArgPhysReg(Argument &Arg) {
2090   auto VRegs = getOrCreateVRegs(Arg);
2091   if (VRegs.size() != 1)
2092     return std::nullopt;
2093 
2094   // Arguments are lowered as a copy of a livein physical register.
2095   auto *VRegDef = MF->getRegInfo().getVRegDef(VRegs[0]);
2096   if (!VRegDef || !VRegDef->isCopy())
2097     return std::nullopt;
2098   return VRegDef->getOperand(1).getReg().asMCReg();
2099 }
2100 
2101 bool IRTranslator::translateIfEntryValueArgument(bool isDeclare, Value *Val,
2102                                                  const DILocalVariable *Var,
2103                                                  const DIExpression *Expr,
2104                                                  const DebugLoc &DL,
2105                                                  MachineIRBuilder &MIRBuilder) {
2106   auto *Arg = dyn_cast<Argument>(Val);
2107   if (!Arg)
2108     return false;
2109 
2110   if (!Expr->isEntryValue())
2111     return false;
2112 
2113   std::optional<MCRegister> PhysReg = getArgPhysReg(*Arg);
2114   if (!PhysReg) {
2115     LLVM_DEBUG(dbgs() << "Dropping dbg." << (isDeclare ? "declare" : "value")
2116                       << ": expression is entry_value but "
2117                       << "couldn't find a physical register\n");
2118     LLVM_DEBUG(dbgs() << *Var << "\n");
2119     return true;
2120   }
2121 
2122   if (isDeclare) {
2123     // Append an op deref to account for the fact that this is a dbg_declare.
2124     Expr = DIExpression::append(Expr, dwarf::DW_OP_deref);
2125     MF->setVariableDbgInfo(Var, Expr, *PhysReg, DL);
2126   } else {
2127     MIRBuilder.buildDirectDbgValue(*PhysReg, Var, Expr);
2128   }
2129 
2130   return true;
2131 }
2132 
2133 static unsigned getConvOpcode(Intrinsic::ID ID) {
2134   switch (ID) {
2135   default:
2136     llvm_unreachable("Unexpected intrinsic");
2137   case Intrinsic::experimental_convergence_anchor:
2138     return TargetOpcode::CONVERGENCECTRL_ANCHOR;
2139   case Intrinsic::experimental_convergence_entry:
2140     return TargetOpcode::CONVERGENCECTRL_ENTRY;
2141   case Intrinsic::experimental_convergence_loop:
2142     return TargetOpcode::CONVERGENCECTRL_LOOP;
2143   }
2144 }
2145 
2146 bool IRTranslator::translateConvergenceControlIntrinsic(
2147     const CallInst &CI, Intrinsic::ID ID, MachineIRBuilder &MIRBuilder) {
2148   MachineInstrBuilder MIB = MIRBuilder.buildInstr(getConvOpcode(ID));
2149   Register OutputReg = getOrCreateConvergenceTokenVReg(CI);
2150   MIB.addDef(OutputReg);
2151 
2152   if (ID == Intrinsic::experimental_convergence_loop) {
2153     auto Bundle = CI.getOperandBundle(LLVMContext::OB_convergencectrl);
2154     assert(Bundle && "Expected a convergence control token.");
2155     Register InputReg =
2156         getOrCreateConvergenceTokenVReg(*Bundle->Inputs[0].get());
2157     MIB.addUse(InputReg);
2158   }
2159 
2160   return true;
2161 }
2162 
2163 bool IRTranslator::translateKnownIntrinsic(const CallInst &CI, Intrinsic::ID ID,
2164                                            MachineIRBuilder &MIRBuilder) {
2165   if (auto *MI = dyn_cast<AnyMemIntrinsic>(&CI)) {
2166     if (ORE->enabled()) {
2167       if (MemoryOpRemark::canHandle(MI, *LibInfo)) {
2168         MemoryOpRemark R(*ORE, "gisel-irtranslator-memsize", *DL, *LibInfo);
2169         R.visit(MI);
2170       }
2171     }
2172   }
2173 
2174   // If this is a simple intrinsic (that is, we just need to add a def of
2175   // a vreg, and uses for each arg operand, then translate it.
2176   if (translateSimpleIntrinsic(CI, ID, MIRBuilder))
2177     return true;
2178 
2179   switch (ID) {
2180   default:
2181     break;
2182   case Intrinsic::lifetime_start:
2183   case Intrinsic::lifetime_end: {
2184     // No stack colouring in O0, discard region information.
2185     if (MF->getTarget().getOptLevel() == CodeGenOptLevel::None ||
2186         MF->getFunction().hasOptNone())
2187       return true;
2188 
2189     unsigned Op = ID == Intrinsic::lifetime_start ? TargetOpcode::LIFETIME_START
2190                                                   : TargetOpcode::LIFETIME_END;
2191 
2192     // Get the underlying objects for the location passed on the lifetime
2193     // marker.
2194     SmallVector<const Value *, 4> Allocas;
2195     getUnderlyingObjects(CI.getArgOperand(1), Allocas);
2196 
2197     // Iterate over each underlying object, creating lifetime markers for each
2198     // static alloca. Quit if we find a non-static alloca.
2199     for (const Value *V : Allocas) {
2200       const AllocaInst *AI = dyn_cast<AllocaInst>(V);
2201       if (!AI)
2202         continue;
2203 
2204       if (!AI->isStaticAlloca())
2205         return true;
2206 
2207       MIRBuilder.buildInstr(Op).addFrameIndex(getOrCreateFrameIndex(*AI));
2208     }
2209     return true;
2210   }
2211   case Intrinsic::fake_use: {
2212     SmallVector<llvm::SrcOp, 4> VRegs;
2213     for (const auto &Arg : CI.args())
2214       llvm::append_range(VRegs, getOrCreateVRegs(*Arg));
2215     MIRBuilder.buildInstr(TargetOpcode::FAKE_USE, {}, VRegs);
2216     MF->setHasFakeUses(true);
2217     return true;
2218   }
2219   case Intrinsic::dbg_declare: {
2220     const DbgDeclareInst &DI = cast<DbgDeclareInst>(CI);
2221     assert(DI.getVariable() && "Missing variable");
2222     translateDbgDeclareRecord(DI.getAddress(), DI.hasArgList(), DI.getVariable(),
2223                        DI.getExpression(), DI.getDebugLoc(), MIRBuilder);
2224     return true;
2225   }
2226   case Intrinsic::dbg_label: {
2227     const DbgLabelInst &DI = cast<DbgLabelInst>(CI);
2228     assert(DI.getLabel() && "Missing label");
2229 
2230     assert(DI.getLabel()->isValidLocationForIntrinsic(
2231                MIRBuilder.getDebugLoc()) &&
2232            "Expected inlined-at fields to agree");
2233 
2234     MIRBuilder.buildDbgLabel(DI.getLabel());
2235     return true;
2236   }
2237   case Intrinsic::vaend:
2238     // No target I know of cares about va_end. Certainly no in-tree target
2239     // does. Simplest intrinsic ever!
2240     return true;
2241   case Intrinsic::vastart: {
2242     Value *Ptr = CI.getArgOperand(0);
2243     unsigned ListSize = TLI->getVaListSizeInBits(*DL) / 8;
2244     Align Alignment = getKnownAlignment(Ptr, *DL);
2245 
2246     MIRBuilder.buildInstr(TargetOpcode::G_VASTART, {}, {getOrCreateVReg(*Ptr)})
2247         .addMemOperand(MF->getMachineMemOperand(MachinePointerInfo(Ptr),
2248                                                 MachineMemOperand::MOStore,
2249                                                 ListSize, Alignment));
2250     return true;
2251   }
2252   case Intrinsic::dbg_assign:
2253     // A dbg.assign is a dbg.value with more information about stack locations,
2254     // typically produced during optimisation of variables with leaked
2255     // addresses. We can treat it like a normal dbg_value intrinsic here; to
2256     // benefit from the full analysis of stack/SSA locations, GlobalISel would
2257     // need to register for and use the AssignmentTrackingAnalysis pass.
2258     [[fallthrough]];
2259   case Intrinsic::dbg_value: {
2260     // This form of DBG_VALUE is target-independent.
2261     const DbgValueInst &DI = cast<DbgValueInst>(CI);
2262     translateDbgValueRecord(DI.getValue(), DI.hasArgList(), DI.getVariable(),
2263                        DI.getExpression(), DI.getDebugLoc(), MIRBuilder);
2264     return true;
2265   }
2266   case Intrinsic::uadd_with_overflow:
2267     return translateOverflowIntrinsic(CI, TargetOpcode::G_UADDO, MIRBuilder);
2268   case Intrinsic::sadd_with_overflow:
2269     return translateOverflowIntrinsic(CI, TargetOpcode::G_SADDO, MIRBuilder);
2270   case Intrinsic::usub_with_overflow:
2271     return translateOverflowIntrinsic(CI, TargetOpcode::G_USUBO, MIRBuilder);
2272   case Intrinsic::ssub_with_overflow:
2273     return translateOverflowIntrinsic(CI, TargetOpcode::G_SSUBO, MIRBuilder);
2274   case Intrinsic::umul_with_overflow:
2275     return translateOverflowIntrinsic(CI, TargetOpcode::G_UMULO, MIRBuilder);
2276   case Intrinsic::smul_with_overflow:
2277     return translateOverflowIntrinsic(CI, TargetOpcode::G_SMULO, MIRBuilder);
2278   case Intrinsic::uadd_sat:
2279     return translateBinaryOp(TargetOpcode::G_UADDSAT, CI, MIRBuilder);
2280   case Intrinsic::sadd_sat:
2281     return translateBinaryOp(TargetOpcode::G_SADDSAT, CI, MIRBuilder);
2282   case Intrinsic::usub_sat:
2283     return translateBinaryOp(TargetOpcode::G_USUBSAT, CI, MIRBuilder);
2284   case Intrinsic::ssub_sat:
2285     return translateBinaryOp(TargetOpcode::G_SSUBSAT, CI, MIRBuilder);
2286   case Intrinsic::ushl_sat:
2287     return translateBinaryOp(TargetOpcode::G_USHLSAT, CI, MIRBuilder);
2288   case Intrinsic::sshl_sat:
2289     return translateBinaryOp(TargetOpcode::G_SSHLSAT, CI, MIRBuilder);
2290   case Intrinsic::umin:
2291     return translateBinaryOp(TargetOpcode::G_UMIN, CI, MIRBuilder);
2292   case Intrinsic::umax:
2293     return translateBinaryOp(TargetOpcode::G_UMAX, CI, MIRBuilder);
2294   case Intrinsic::smin:
2295     return translateBinaryOp(TargetOpcode::G_SMIN, CI, MIRBuilder);
2296   case Intrinsic::smax:
2297     return translateBinaryOp(TargetOpcode::G_SMAX, CI, MIRBuilder);
2298   case Intrinsic::abs:
2299     // TODO: Preserve "int min is poison" arg in GMIR?
2300     return translateUnaryOp(TargetOpcode::G_ABS, CI, MIRBuilder);
2301   case Intrinsic::smul_fix:
2302     return translateFixedPointIntrinsic(TargetOpcode::G_SMULFIX, CI, MIRBuilder);
2303   case Intrinsic::umul_fix:
2304     return translateFixedPointIntrinsic(TargetOpcode::G_UMULFIX, CI, MIRBuilder);
2305   case Intrinsic::smul_fix_sat:
2306     return translateFixedPointIntrinsic(TargetOpcode::G_SMULFIXSAT, CI, MIRBuilder);
2307   case Intrinsic::umul_fix_sat:
2308     return translateFixedPointIntrinsic(TargetOpcode::G_UMULFIXSAT, CI, MIRBuilder);
2309   case Intrinsic::sdiv_fix:
2310     return translateFixedPointIntrinsic(TargetOpcode::G_SDIVFIX, CI, MIRBuilder);
2311   case Intrinsic::udiv_fix:
2312     return translateFixedPointIntrinsic(TargetOpcode::G_UDIVFIX, CI, MIRBuilder);
2313   case Intrinsic::sdiv_fix_sat:
2314     return translateFixedPointIntrinsic(TargetOpcode::G_SDIVFIXSAT, CI, MIRBuilder);
2315   case Intrinsic::udiv_fix_sat:
2316     return translateFixedPointIntrinsic(TargetOpcode::G_UDIVFIXSAT, CI, MIRBuilder);
2317   case Intrinsic::fmuladd: {
2318     const TargetMachine &TM = MF->getTarget();
2319     Register Dst = getOrCreateVReg(CI);
2320     Register Op0 = getOrCreateVReg(*CI.getArgOperand(0));
2321     Register Op1 = getOrCreateVReg(*CI.getArgOperand(1));
2322     Register Op2 = getOrCreateVReg(*CI.getArgOperand(2));
2323     if (TM.Options.AllowFPOpFusion != FPOpFusion::Strict &&
2324         TLI->isFMAFasterThanFMulAndFAdd(*MF,
2325                                         TLI->getValueType(*DL, CI.getType()))) {
2326       // TODO: Revisit this to see if we should move this part of the
2327       // lowering to the combiner.
2328       MIRBuilder.buildFMA(Dst, Op0, Op1, Op2,
2329                           MachineInstr::copyFlagsFromInstruction(CI));
2330     } else {
2331       LLT Ty = getLLTForType(*CI.getType(), *DL);
2332       auto FMul = MIRBuilder.buildFMul(
2333           Ty, Op0, Op1, MachineInstr::copyFlagsFromInstruction(CI));
2334       MIRBuilder.buildFAdd(Dst, FMul, Op2,
2335                            MachineInstr::copyFlagsFromInstruction(CI));
2336     }
2337     return true;
2338   }
2339   case Intrinsic::convert_from_fp16:
2340     // FIXME: This intrinsic should probably be removed from the IR.
2341     MIRBuilder.buildFPExt(getOrCreateVReg(CI),
2342                           getOrCreateVReg(*CI.getArgOperand(0)),
2343                           MachineInstr::copyFlagsFromInstruction(CI));
2344     return true;
2345   case Intrinsic::convert_to_fp16:
2346     // FIXME: This intrinsic should probably be removed from the IR.
2347     MIRBuilder.buildFPTrunc(getOrCreateVReg(CI),
2348                             getOrCreateVReg(*CI.getArgOperand(0)),
2349                             MachineInstr::copyFlagsFromInstruction(CI));
2350     return true;
2351   case Intrinsic::frexp: {
2352     ArrayRef<Register> VRegs = getOrCreateVRegs(CI);
2353     MIRBuilder.buildFFrexp(VRegs[0], VRegs[1],
2354                            getOrCreateVReg(*CI.getArgOperand(0)),
2355                            MachineInstr::copyFlagsFromInstruction(CI));
2356     return true;
2357   }
2358   case Intrinsic::sincos: {
2359     ArrayRef<Register> VRegs = getOrCreateVRegs(CI);
2360     MIRBuilder.buildFSincos(VRegs[0], VRegs[1],
2361                             getOrCreateVReg(*CI.getArgOperand(0)),
2362                             MachineInstr::copyFlagsFromInstruction(CI));
2363     return true;
2364   }
2365   case Intrinsic::fptosi_sat:
2366     MIRBuilder.buildFPTOSI_SAT(getOrCreateVReg(CI),
2367                                getOrCreateVReg(*CI.getArgOperand(0)));
2368     return true;
2369   case Intrinsic::fptoui_sat:
2370     MIRBuilder.buildFPTOUI_SAT(getOrCreateVReg(CI),
2371                                getOrCreateVReg(*CI.getArgOperand(0)));
2372     return true;
2373   case Intrinsic::memcpy_inline:
2374     return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMCPY_INLINE);
2375   case Intrinsic::memcpy:
2376     return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMCPY);
2377   case Intrinsic::memmove:
2378     return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMMOVE);
2379   case Intrinsic::memset:
2380     return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMSET);
2381   case Intrinsic::eh_typeid_for: {
2382     GlobalValue *GV = ExtractTypeInfo(CI.getArgOperand(0));
2383     Register Reg = getOrCreateVReg(CI);
2384     unsigned TypeID = MF->getTypeIDFor(GV);
2385     MIRBuilder.buildConstant(Reg, TypeID);
2386     return true;
2387   }
2388   case Intrinsic::objectsize:
2389     llvm_unreachable("llvm.objectsize.* should have been lowered already");
2390 
2391   case Intrinsic::is_constant:
2392     llvm_unreachable("llvm.is.constant.* should have been lowered already");
2393 
2394   case Intrinsic::stackguard:
2395     getStackGuard(getOrCreateVReg(CI), MIRBuilder);
2396     return true;
2397   case Intrinsic::stackprotector: {
2398     LLT PtrTy = getLLTForType(*CI.getArgOperand(0)->getType(), *DL);
2399     Register GuardVal;
2400     if (TLI->useLoadStackGuardNode(*CI.getModule())) {
2401       GuardVal = MRI->createGenericVirtualRegister(PtrTy);
2402       getStackGuard(GuardVal, MIRBuilder);
2403     } else
2404       GuardVal = getOrCreateVReg(*CI.getArgOperand(0)); // The guard's value.
2405 
2406     AllocaInst *Slot = cast<AllocaInst>(CI.getArgOperand(1));
2407     int FI = getOrCreateFrameIndex(*Slot);
2408     MF->getFrameInfo().setStackProtectorIndex(FI);
2409 
2410     MIRBuilder.buildStore(
2411         GuardVal, getOrCreateVReg(*Slot),
2412         *MF->getMachineMemOperand(MachinePointerInfo::getFixedStack(*MF, FI),
2413                                   MachineMemOperand::MOStore |
2414                                       MachineMemOperand::MOVolatile,
2415                                   PtrTy, Align(8)));
2416     return true;
2417   }
2418   case Intrinsic::stacksave: {
2419     MIRBuilder.buildInstr(TargetOpcode::G_STACKSAVE, {getOrCreateVReg(CI)}, {});
2420     return true;
2421   }
2422   case Intrinsic::stackrestore: {
2423     MIRBuilder.buildInstr(TargetOpcode::G_STACKRESTORE, {},
2424                           {getOrCreateVReg(*CI.getArgOperand(0))});
2425     return true;
2426   }
2427   case Intrinsic::cttz:
2428   case Intrinsic::ctlz: {
2429     ConstantInt *Cst = cast<ConstantInt>(CI.getArgOperand(1));
2430     bool isTrailing = ID == Intrinsic::cttz;
2431     unsigned Opcode = isTrailing
2432                           ? Cst->isZero() ? TargetOpcode::G_CTTZ
2433                                           : TargetOpcode::G_CTTZ_ZERO_UNDEF
2434                           : Cst->isZero() ? TargetOpcode::G_CTLZ
2435                                           : TargetOpcode::G_CTLZ_ZERO_UNDEF;
2436     MIRBuilder.buildInstr(Opcode, {getOrCreateVReg(CI)},
2437                           {getOrCreateVReg(*CI.getArgOperand(0))});
2438     return true;
2439   }
2440   case Intrinsic::invariant_start: {
2441     MIRBuilder.buildUndef(getOrCreateVReg(CI));
2442     return true;
2443   }
2444   case Intrinsic::invariant_end:
2445     return true;
2446   case Intrinsic::expect:
2447   case Intrinsic::expect_with_probability:
2448   case Intrinsic::annotation:
2449   case Intrinsic::ptr_annotation:
2450   case Intrinsic::launder_invariant_group:
2451   case Intrinsic::strip_invariant_group: {
2452     // Drop the intrinsic, but forward the value.
2453     MIRBuilder.buildCopy(getOrCreateVReg(CI),
2454                          getOrCreateVReg(*CI.getArgOperand(0)));
2455     return true;
2456   }
2457   case Intrinsic::assume:
2458   case Intrinsic::experimental_noalias_scope_decl:
2459   case Intrinsic::var_annotation:
2460   case Intrinsic::sideeffect:
2461     // Discard annotate attributes, assumptions, and artificial side-effects.
2462     return true;
2463   case Intrinsic::read_volatile_register:
2464   case Intrinsic::read_register: {
2465     Value *Arg = CI.getArgOperand(0);
2466     MIRBuilder
2467         .buildInstr(TargetOpcode::G_READ_REGISTER, {getOrCreateVReg(CI)}, {})
2468         .addMetadata(cast<MDNode>(cast<MetadataAsValue>(Arg)->getMetadata()));
2469     return true;
2470   }
2471   case Intrinsic::write_register: {
2472     Value *Arg = CI.getArgOperand(0);
2473     MIRBuilder.buildInstr(TargetOpcode::G_WRITE_REGISTER)
2474       .addMetadata(cast<MDNode>(cast<MetadataAsValue>(Arg)->getMetadata()))
2475       .addUse(getOrCreateVReg(*CI.getArgOperand(1)));
2476     return true;
2477   }
2478   case Intrinsic::localescape: {
2479     MachineBasicBlock &EntryMBB = MF->front();
2480     StringRef EscapedName = GlobalValue::dropLLVMManglingEscape(MF->getName());
2481 
2482     // Directly emit some LOCAL_ESCAPE machine instrs. Label assignment emission
2483     // is the same on all targets.
2484     for (unsigned Idx = 0, E = CI.arg_size(); Idx < E; ++Idx) {
2485       Value *Arg = CI.getArgOperand(Idx)->stripPointerCasts();
2486       if (isa<ConstantPointerNull>(Arg))
2487         continue; // Skip null pointers. They represent a hole in index space.
2488 
2489       int FI = getOrCreateFrameIndex(*cast<AllocaInst>(Arg));
2490       MCSymbol *FrameAllocSym =
2491           MF->getContext().getOrCreateFrameAllocSymbol(EscapedName, Idx);
2492 
2493       // This should be inserted at the start of the entry block.
2494       auto LocalEscape =
2495           MIRBuilder.buildInstrNoInsert(TargetOpcode::LOCAL_ESCAPE)
2496               .addSym(FrameAllocSym)
2497               .addFrameIndex(FI);
2498 
2499       EntryMBB.insert(EntryMBB.begin(), LocalEscape);
2500     }
2501 
2502     return true;
2503   }
2504   case Intrinsic::vector_reduce_fadd:
2505   case Intrinsic::vector_reduce_fmul: {
2506     // Need to check for the reassoc flag to decide whether we want a
2507     // sequential reduction opcode or not.
2508     Register Dst = getOrCreateVReg(CI);
2509     Register ScalarSrc = getOrCreateVReg(*CI.getArgOperand(0));
2510     Register VecSrc = getOrCreateVReg(*CI.getArgOperand(1));
2511     unsigned Opc = 0;
2512     if (!CI.hasAllowReassoc()) {
2513       // The sequential ordering case.
2514       Opc = ID == Intrinsic::vector_reduce_fadd
2515                 ? TargetOpcode::G_VECREDUCE_SEQ_FADD
2516                 : TargetOpcode::G_VECREDUCE_SEQ_FMUL;
2517       MIRBuilder.buildInstr(Opc, {Dst}, {ScalarSrc, VecSrc},
2518                             MachineInstr::copyFlagsFromInstruction(CI));
2519       return true;
2520     }
2521     // We split the operation into a separate G_FADD/G_FMUL + the reduce,
2522     // since the associativity doesn't matter.
2523     unsigned ScalarOpc;
2524     if (ID == Intrinsic::vector_reduce_fadd) {
2525       Opc = TargetOpcode::G_VECREDUCE_FADD;
2526       ScalarOpc = TargetOpcode::G_FADD;
2527     } else {
2528       Opc = TargetOpcode::G_VECREDUCE_FMUL;
2529       ScalarOpc = TargetOpcode::G_FMUL;
2530     }
2531     LLT DstTy = MRI->getType(Dst);
2532     auto Rdx = MIRBuilder.buildInstr(
2533         Opc, {DstTy}, {VecSrc}, MachineInstr::copyFlagsFromInstruction(CI));
2534     MIRBuilder.buildInstr(ScalarOpc, {Dst}, {ScalarSrc, Rdx},
2535                           MachineInstr::copyFlagsFromInstruction(CI));
2536 
2537     return true;
2538   }
2539   case Intrinsic::trap:
2540     return translateTrap(CI, MIRBuilder, TargetOpcode::G_TRAP);
2541   case Intrinsic::debugtrap:
2542     return translateTrap(CI, MIRBuilder, TargetOpcode::G_DEBUGTRAP);
2543   case Intrinsic::ubsantrap:
2544     return translateTrap(CI, MIRBuilder, TargetOpcode::G_UBSANTRAP);
2545   case Intrinsic::allow_runtime_check:
2546   case Intrinsic::allow_ubsan_check:
2547     MIRBuilder.buildCopy(getOrCreateVReg(CI),
2548                          getOrCreateVReg(*ConstantInt::getTrue(CI.getType())));
2549     return true;
2550   case Intrinsic::amdgcn_cs_chain:
2551     return translateCallBase(CI, MIRBuilder);
2552   case Intrinsic::fptrunc_round: {
2553     uint32_t Flags = MachineInstr::copyFlagsFromInstruction(CI);
2554 
2555     // Convert the metadata argument to a constant integer
2556     Metadata *MD = cast<MetadataAsValue>(CI.getArgOperand(1))->getMetadata();
2557     std::optional<RoundingMode> RoundMode =
2558         convertStrToRoundingMode(cast<MDString>(MD)->getString());
2559 
2560     // Add the Rounding mode as an integer
2561     MIRBuilder
2562         .buildInstr(TargetOpcode::G_INTRINSIC_FPTRUNC_ROUND,
2563                     {getOrCreateVReg(CI)},
2564                     {getOrCreateVReg(*CI.getArgOperand(0))}, Flags)
2565         .addImm((int)*RoundMode);
2566 
2567     return true;
2568   }
2569   case Intrinsic::is_fpclass: {
2570     Value *FpValue = CI.getOperand(0);
2571     ConstantInt *TestMaskValue = cast<ConstantInt>(CI.getOperand(1));
2572 
2573     MIRBuilder
2574         .buildInstr(TargetOpcode::G_IS_FPCLASS, {getOrCreateVReg(CI)},
2575                     {getOrCreateVReg(*FpValue)})
2576         .addImm(TestMaskValue->getZExtValue());
2577 
2578     return true;
2579   }
2580   case Intrinsic::set_fpenv: {
2581     Value *FPEnv = CI.getOperand(0);
2582     MIRBuilder.buildSetFPEnv(getOrCreateVReg(*FPEnv));
2583     return true;
2584   }
2585   case Intrinsic::reset_fpenv:
2586     MIRBuilder.buildResetFPEnv();
2587     return true;
2588   case Intrinsic::set_fpmode: {
2589     Value *FPState = CI.getOperand(0);
2590     MIRBuilder.buildSetFPMode(getOrCreateVReg(*FPState));
2591     return true;
2592   }
2593   case Intrinsic::reset_fpmode:
2594     MIRBuilder.buildResetFPMode();
2595     return true;
2596   case Intrinsic::get_rounding:
2597     MIRBuilder.buildGetRounding(getOrCreateVReg(CI));
2598     return true;
2599   case Intrinsic::vscale: {
2600     MIRBuilder.buildVScale(getOrCreateVReg(CI), 1);
2601     return true;
2602   }
2603   case Intrinsic::scmp:
2604     MIRBuilder.buildSCmp(getOrCreateVReg(CI),
2605                          getOrCreateVReg(*CI.getOperand(0)),
2606                          getOrCreateVReg(*CI.getOperand(1)));
2607     return true;
2608   case Intrinsic::ucmp:
2609     MIRBuilder.buildUCmp(getOrCreateVReg(CI),
2610                          getOrCreateVReg(*CI.getOperand(0)),
2611                          getOrCreateVReg(*CI.getOperand(1)));
2612     return true;
2613   case Intrinsic::vector_extract:
2614     return translateExtractVector(CI, MIRBuilder);
2615   case Intrinsic::vector_insert:
2616     return translateInsertVector(CI, MIRBuilder);
2617   case Intrinsic::stepvector: {
2618     MIRBuilder.buildStepVector(getOrCreateVReg(CI), 1);
2619     return true;
2620   }
2621   case Intrinsic::prefetch: {
2622     Value *Addr = CI.getOperand(0);
2623     unsigned RW = cast<ConstantInt>(CI.getOperand(1))->getZExtValue();
2624     unsigned Locality = cast<ConstantInt>(CI.getOperand(2))->getZExtValue();
2625     unsigned CacheType = cast<ConstantInt>(CI.getOperand(3))->getZExtValue();
2626 
2627     auto Flags = RW ? MachineMemOperand::MOStore : MachineMemOperand::MOLoad;
2628     auto &MMO = *MF->getMachineMemOperand(MachinePointerInfo(Addr), Flags,
2629                                           LLT(), Align());
2630 
2631     MIRBuilder.buildPrefetch(getOrCreateVReg(*Addr), RW, Locality, CacheType,
2632                              MMO);
2633 
2634     return true;
2635   }
2636 
2637   case Intrinsic::vector_interleave2:
2638   case Intrinsic::vector_deinterleave2: {
2639     // Both intrinsics have at least one operand.
2640     Value *Op0 = CI.getOperand(0);
2641     LLT ResTy = getLLTForType(*Op0->getType(), MIRBuilder.getDataLayout());
2642     if (!ResTy.isFixedVector())
2643       return false;
2644 
2645     if (CI.getIntrinsicID() == Intrinsic::vector_interleave2)
2646       return translateVectorInterleave2Intrinsic(CI, MIRBuilder);
2647 
2648     return translateVectorDeinterleave2Intrinsic(CI, MIRBuilder);
2649   }
2650 
2651 #define INSTRUCTION(NAME, NARG, ROUND_MODE, INTRINSIC)  \
2652   case Intrinsic::INTRINSIC:
2653 #include "llvm/IR/ConstrainedOps.def"
2654     return translateConstrainedFPIntrinsic(cast<ConstrainedFPIntrinsic>(CI),
2655                                            MIRBuilder);
2656   case Intrinsic::experimental_convergence_anchor:
2657   case Intrinsic::experimental_convergence_entry:
2658   case Intrinsic::experimental_convergence_loop:
2659     return translateConvergenceControlIntrinsic(CI, ID, MIRBuilder);
2660   }
2661   return false;
2662 }
2663 
2664 bool IRTranslator::translateInlineAsm(const CallBase &CB,
2665                                       MachineIRBuilder &MIRBuilder) {
2666   if (containsBF16Type(CB))
2667     return false;
2668 
2669   const InlineAsmLowering *ALI = MF->getSubtarget().getInlineAsmLowering();
2670 
2671   if (!ALI) {
2672     LLVM_DEBUG(
2673         dbgs() << "Inline asm lowering is not supported for this target yet\n");
2674     return false;
2675   }
2676 
2677   return ALI->lowerInlineAsm(
2678       MIRBuilder, CB, [&](const Value &Val) { return getOrCreateVRegs(Val); });
2679 }
2680 
2681 bool IRTranslator::translateCallBase(const CallBase &CB,
2682                                      MachineIRBuilder &MIRBuilder) {
2683   ArrayRef<Register> Res = getOrCreateVRegs(CB);
2684 
2685   SmallVector<ArrayRef<Register>, 8> Args;
2686   Register SwiftInVReg = 0;
2687   Register SwiftErrorVReg = 0;
2688   for (const auto &Arg : CB.args()) {
2689     if (CLI->supportSwiftError() && isSwiftError(Arg)) {
2690       assert(SwiftInVReg == 0 && "Expected only one swift error argument");
2691       LLT Ty = getLLTForType(*Arg->getType(), *DL);
2692       SwiftInVReg = MRI->createGenericVirtualRegister(Ty);
2693       MIRBuilder.buildCopy(SwiftInVReg, SwiftError.getOrCreateVRegUseAt(
2694                                             &CB, &MIRBuilder.getMBB(), Arg));
2695       Args.emplace_back(ArrayRef(SwiftInVReg));
2696       SwiftErrorVReg =
2697           SwiftError.getOrCreateVRegDefAt(&CB, &MIRBuilder.getMBB(), Arg);
2698       continue;
2699     }
2700     Args.push_back(getOrCreateVRegs(*Arg));
2701   }
2702 
2703   if (auto *CI = dyn_cast<CallInst>(&CB)) {
2704     if (ORE->enabled()) {
2705       if (MemoryOpRemark::canHandle(CI, *LibInfo)) {
2706         MemoryOpRemark R(*ORE, "gisel-irtranslator-memsize", *DL, *LibInfo);
2707         R.visit(CI);
2708       }
2709     }
2710   }
2711 
2712   std::optional<CallLowering::PtrAuthInfo> PAI;
2713   if (auto Bundle = CB.getOperandBundle(LLVMContext::OB_ptrauth)) {
2714     // Functions should never be ptrauth-called directly.
2715     assert(!CB.getCalledFunction() && "invalid direct ptrauth call");
2716 
2717     const Value *Key = Bundle->Inputs[0];
2718     const Value *Discriminator = Bundle->Inputs[1];
2719 
2720     // Look through ptrauth constants to try to eliminate the matching bundle
2721     // and turn this into a direct call with no ptrauth.
2722     // CallLowering will use the raw pointer if it doesn't find the PAI.
2723     const auto *CalleeCPA = dyn_cast<ConstantPtrAuth>(CB.getCalledOperand());
2724     if (!CalleeCPA || !isa<Function>(CalleeCPA->getPointer()) ||
2725         !CalleeCPA->isKnownCompatibleWith(Key, Discriminator, *DL)) {
2726       // If we can't make it direct, package the bundle into PAI.
2727       Register DiscReg = getOrCreateVReg(*Discriminator);
2728       PAI = CallLowering::PtrAuthInfo{cast<ConstantInt>(Key)->getZExtValue(),
2729                                       DiscReg};
2730     }
2731   }
2732 
2733   Register ConvergenceCtrlToken = 0;
2734   if (auto Bundle = CB.getOperandBundle(LLVMContext::OB_convergencectrl)) {
2735     const auto &Token = *Bundle->Inputs[0].get();
2736     ConvergenceCtrlToken = getOrCreateConvergenceTokenVReg(Token);
2737   }
2738 
2739   // We don't set HasCalls on MFI here yet because call lowering may decide to
2740   // optimize into tail calls. Instead, we defer that to selection where a final
2741   // scan is done to check if any instructions are calls.
2742   bool Success = CLI->lowerCall(
2743       MIRBuilder, CB, Res, Args, SwiftErrorVReg, PAI, ConvergenceCtrlToken,
2744       [&]() { return getOrCreateVReg(*CB.getCalledOperand()); });
2745 
2746   // Check if we just inserted a tail call.
2747   if (Success) {
2748     assert(!HasTailCall && "Can't tail call return twice from block?");
2749     const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
2750     HasTailCall = TII->isTailCall(*std::prev(MIRBuilder.getInsertPt()));
2751   }
2752 
2753   return Success;
2754 }
2755 
2756 bool IRTranslator::translateCall(const User &U, MachineIRBuilder &MIRBuilder) {
2757   if (containsBF16Type(U))
2758     return false;
2759 
2760   const CallInst &CI = cast<CallInst>(U);
2761   const Function *F = CI.getCalledFunction();
2762 
2763   // FIXME: support Windows dllimport function calls and calls through
2764   // weak symbols.
2765   if (F && (F->hasDLLImportStorageClass() ||
2766             (MF->getTarget().getTargetTriple().isOSWindows() &&
2767              F->hasExternalWeakLinkage())))
2768     return false;
2769 
2770   // FIXME: support control flow guard targets.
2771   if (CI.countOperandBundlesOfType(LLVMContext::OB_cfguardtarget))
2772     return false;
2773 
2774   // FIXME: support statepoints and related.
2775   if (isa<GCStatepointInst, GCRelocateInst, GCResultInst>(U))
2776     return false;
2777 
2778   if (CI.isInlineAsm())
2779     return translateInlineAsm(CI, MIRBuilder);
2780 
2781   diagnoseDontCall(CI);
2782 
2783   Intrinsic::ID ID = F ? F->getIntrinsicID() : Intrinsic::not_intrinsic;
2784   if (!F || ID == Intrinsic::not_intrinsic)
2785     return translateCallBase(CI, MIRBuilder);
2786 
2787   assert(ID != Intrinsic::not_intrinsic && "unknown intrinsic");
2788 
2789   if (translateKnownIntrinsic(CI, ID, MIRBuilder))
2790     return true;
2791 
2792   ArrayRef<Register> ResultRegs;
2793   if (!CI.getType()->isVoidTy())
2794     ResultRegs = getOrCreateVRegs(CI);
2795 
2796   // Ignore the callsite attributes. Backend code is most likely not expecting
2797   // an intrinsic to sometimes have side effects and sometimes not.
2798   MachineInstrBuilder MIB = MIRBuilder.buildIntrinsic(ID, ResultRegs);
2799   if (isa<FPMathOperator>(CI))
2800     MIB->copyIRFlags(CI);
2801 
2802   for (const auto &Arg : enumerate(CI.args())) {
2803     // If this is required to be an immediate, don't materialize it in a
2804     // register.
2805     if (CI.paramHasAttr(Arg.index(), Attribute::ImmArg)) {
2806       if (ConstantInt *CI = dyn_cast<ConstantInt>(Arg.value())) {
2807         // imm arguments are more convenient than cimm (and realistically
2808         // probably sufficient), so use them.
2809         assert(CI->getBitWidth() <= 64 &&
2810                "large intrinsic immediates not handled");
2811         MIB.addImm(CI->getSExtValue());
2812       } else {
2813         MIB.addFPImm(cast<ConstantFP>(Arg.value()));
2814       }
2815     } else if (auto *MDVal = dyn_cast<MetadataAsValue>(Arg.value())) {
2816       auto *MD = MDVal->getMetadata();
2817       auto *MDN = dyn_cast<MDNode>(MD);
2818       if (!MDN) {
2819         if (auto *ConstMD = dyn_cast<ConstantAsMetadata>(MD))
2820           MDN = MDNode::get(MF->getFunction().getContext(), ConstMD);
2821         else // This was probably an MDString.
2822           return false;
2823       }
2824       MIB.addMetadata(MDN);
2825     } else {
2826       ArrayRef<Register> VRegs = getOrCreateVRegs(*Arg.value());
2827       if (VRegs.size() > 1)
2828         return false;
2829       MIB.addUse(VRegs[0]);
2830     }
2831   }
2832 
2833   // Add a MachineMemOperand if it is a target mem intrinsic.
2834   TargetLowering::IntrinsicInfo Info;
2835   // TODO: Add a GlobalISel version of getTgtMemIntrinsic.
2836   if (TLI->getTgtMemIntrinsic(Info, CI, *MF, ID)) {
2837     Align Alignment = Info.align.value_or(
2838         DL->getABITypeAlign(Info.memVT.getTypeForEVT(F->getContext())));
2839     LLT MemTy = Info.memVT.isSimple()
2840                     ? getLLTForMVT(Info.memVT.getSimpleVT())
2841                     : LLT::scalar(Info.memVT.getStoreSizeInBits());
2842 
2843     // TODO: We currently just fallback to address space 0 if getTgtMemIntrinsic
2844     //       didn't yield anything useful.
2845     MachinePointerInfo MPI;
2846     if (Info.ptrVal)
2847       MPI = MachinePointerInfo(Info.ptrVal, Info.offset);
2848     else if (Info.fallbackAddressSpace)
2849       MPI = MachinePointerInfo(*Info.fallbackAddressSpace);
2850     MIB.addMemOperand(MF->getMachineMemOperand(
2851         MPI, Info.flags, MemTy, Alignment, CI.getAAMetadata(),
2852         /*Ranges=*/nullptr, Info.ssid, Info.order, Info.failureOrder));
2853   }
2854 
2855   if (CI.isConvergent()) {
2856     if (auto Bundle = CI.getOperandBundle(LLVMContext::OB_convergencectrl)) {
2857       auto *Token = Bundle->Inputs[0].get();
2858       Register TokenReg = getOrCreateVReg(*Token);
2859       MIB.addUse(TokenReg, RegState::Implicit);
2860     }
2861   }
2862 
2863   return true;
2864 }
2865 
2866 bool IRTranslator::findUnwindDestinations(
2867     const BasicBlock *EHPadBB,
2868     BranchProbability Prob,
2869     SmallVectorImpl<std::pair<MachineBasicBlock *, BranchProbability>>
2870         &UnwindDests) {
2871   EHPersonality Personality = classifyEHPersonality(
2872       EHPadBB->getParent()->getFunction().getPersonalityFn());
2873   bool IsMSVCCXX = Personality == EHPersonality::MSVC_CXX;
2874   bool IsCoreCLR = Personality == EHPersonality::CoreCLR;
2875   bool IsWasmCXX = Personality == EHPersonality::Wasm_CXX;
2876   bool IsSEH = isAsynchronousEHPersonality(Personality);
2877 
2878   if (IsWasmCXX) {
2879     // Ignore this for now.
2880     return false;
2881   }
2882 
2883   while (EHPadBB) {
2884     BasicBlock::const_iterator Pad = EHPadBB->getFirstNonPHIIt();
2885     BasicBlock *NewEHPadBB = nullptr;
2886     if (isa<LandingPadInst>(Pad)) {
2887       // Stop on landingpads. They are not funclets.
2888       UnwindDests.emplace_back(&getMBB(*EHPadBB), Prob);
2889       break;
2890     }
2891     if (isa<CleanupPadInst>(Pad)) {
2892       // Stop on cleanup pads. Cleanups are always funclet entries for all known
2893       // personalities.
2894       UnwindDests.emplace_back(&getMBB(*EHPadBB), Prob);
2895       UnwindDests.back().first->setIsEHScopeEntry();
2896       UnwindDests.back().first->setIsEHFuncletEntry();
2897       break;
2898     }
2899     if (auto *CatchSwitch = dyn_cast<CatchSwitchInst>(Pad)) {
2900       // Add the catchpad handlers to the possible destinations.
2901       for (const BasicBlock *CatchPadBB : CatchSwitch->handlers()) {
2902         UnwindDests.emplace_back(&getMBB(*CatchPadBB), Prob);
2903         // For MSVC++ and the CLR, catchblocks are funclets and need prologues.
2904         if (IsMSVCCXX || IsCoreCLR)
2905           UnwindDests.back().first->setIsEHFuncletEntry();
2906         if (!IsSEH)
2907           UnwindDests.back().first->setIsEHScopeEntry();
2908       }
2909       NewEHPadBB = CatchSwitch->getUnwindDest();
2910     } else {
2911       continue;
2912     }
2913 
2914     BranchProbabilityInfo *BPI = FuncInfo.BPI;
2915     if (BPI && NewEHPadBB)
2916       Prob *= BPI->getEdgeProbability(EHPadBB, NewEHPadBB);
2917     EHPadBB = NewEHPadBB;
2918   }
2919   return true;
2920 }
2921 
2922 bool IRTranslator::translateInvoke(const User &U,
2923                                    MachineIRBuilder &MIRBuilder) {
2924   const InvokeInst &I = cast<InvokeInst>(U);
2925   MCContext &Context = MF->getContext();
2926 
2927   const BasicBlock *ReturnBB = I.getSuccessor(0);
2928   const BasicBlock *EHPadBB = I.getSuccessor(1);
2929 
2930   const Function *Fn = I.getCalledFunction();
2931 
2932   // FIXME: support invoking patchpoint and statepoint intrinsics.
2933   if (Fn && Fn->isIntrinsic())
2934     return false;
2935 
2936   // FIXME: support whatever these are.
2937   if (I.hasDeoptState())
2938     return false;
2939 
2940   // FIXME: support control flow guard targets.
2941   if (I.countOperandBundlesOfType(LLVMContext::OB_cfguardtarget))
2942     return false;
2943 
2944   // FIXME: support Windows exception handling.
2945   if (!isa<LandingPadInst>(EHPadBB->getFirstNonPHIIt()))
2946     return false;
2947 
2948   // FIXME: support Windows dllimport function calls and calls through
2949   // weak symbols.
2950   if (Fn && (Fn->hasDLLImportStorageClass() ||
2951             (MF->getTarget().getTargetTriple().isOSWindows() &&
2952              Fn->hasExternalWeakLinkage())))
2953     return false;
2954 
2955   bool LowerInlineAsm = I.isInlineAsm();
2956   bool NeedEHLabel = true;
2957 
2958   // Emit the actual call, bracketed by EH_LABELs so that the MF knows about
2959   // the region covered by the try.
2960   MCSymbol *BeginSymbol = nullptr;
2961   if (NeedEHLabel) {
2962     MIRBuilder.buildInstr(TargetOpcode::G_INVOKE_REGION_START);
2963     BeginSymbol = Context.createTempSymbol();
2964     MIRBuilder.buildInstr(TargetOpcode::EH_LABEL).addSym(BeginSymbol);
2965   }
2966 
2967   if (LowerInlineAsm) {
2968     if (!translateInlineAsm(I, MIRBuilder))
2969       return false;
2970   } else if (!translateCallBase(I, MIRBuilder))
2971     return false;
2972 
2973   MCSymbol *EndSymbol = nullptr;
2974   if (NeedEHLabel) {
2975     EndSymbol = Context.createTempSymbol();
2976     MIRBuilder.buildInstr(TargetOpcode::EH_LABEL).addSym(EndSymbol);
2977   }
2978 
2979   SmallVector<std::pair<MachineBasicBlock *, BranchProbability>, 1> UnwindDests;
2980   BranchProbabilityInfo *BPI = FuncInfo.BPI;
2981   MachineBasicBlock *InvokeMBB = &MIRBuilder.getMBB();
2982   BranchProbability EHPadBBProb =
2983       BPI ? BPI->getEdgeProbability(InvokeMBB->getBasicBlock(), EHPadBB)
2984           : BranchProbability::getZero();
2985 
2986   if (!findUnwindDestinations(EHPadBB, EHPadBBProb, UnwindDests))
2987     return false;
2988 
2989   MachineBasicBlock &EHPadMBB = getMBB(*EHPadBB),
2990                     &ReturnMBB = getMBB(*ReturnBB);
2991   // Update successor info.
2992   addSuccessorWithProb(InvokeMBB, &ReturnMBB);
2993   for (auto &UnwindDest : UnwindDests) {
2994     UnwindDest.first->setIsEHPad();
2995     addSuccessorWithProb(InvokeMBB, UnwindDest.first, UnwindDest.second);
2996   }
2997   InvokeMBB->normalizeSuccProbs();
2998 
2999   if (NeedEHLabel) {
3000     assert(BeginSymbol && "Expected a begin symbol!");
3001     assert(EndSymbol && "Expected an end symbol!");
3002     MF->addInvoke(&EHPadMBB, BeginSymbol, EndSymbol);
3003   }
3004 
3005   MIRBuilder.buildBr(ReturnMBB);
3006   return true;
3007 }
3008 
3009 bool IRTranslator::translateCallBr(const User &U,
3010                                    MachineIRBuilder &MIRBuilder) {
3011   // FIXME: Implement this.
3012   return false;
3013 }
3014 
3015 bool IRTranslator::translateLandingPad(const User &U,
3016                                        MachineIRBuilder &MIRBuilder) {
3017   const LandingPadInst &LP = cast<LandingPadInst>(U);
3018 
3019   MachineBasicBlock &MBB = MIRBuilder.getMBB();
3020 
3021   MBB.setIsEHPad();
3022 
3023   // If there aren't registers to copy the values into (e.g., during SjLj
3024   // exceptions), then don't bother.
3025   const Constant *PersonalityFn = MF->getFunction().getPersonalityFn();
3026   if (TLI->getExceptionPointerRegister(PersonalityFn) == 0 &&
3027       TLI->getExceptionSelectorRegister(PersonalityFn) == 0)
3028     return true;
3029 
3030   // If landingpad's return type is token type, we don't create DAG nodes
3031   // for its exception pointer and selector value. The extraction of exception
3032   // pointer or selector value from token type landingpads is not currently
3033   // supported.
3034   if (LP.getType()->isTokenTy())
3035     return true;
3036 
3037   // Add a label to mark the beginning of the landing pad.  Deletion of the
3038   // landing pad can thus be detected via the MachineModuleInfo.
3039   MIRBuilder.buildInstr(TargetOpcode::EH_LABEL)
3040     .addSym(MF->addLandingPad(&MBB));
3041 
3042   // If the unwinder does not preserve all registers, ensure that the
3043   // function marks the clobbered registers as used.
3044   const TargetRegisterInfo &TRI = *MF->getSubtarget().getRegisterInfo();
3045   if (auto *RegMask = TRI.getCustomEHPadPreservedMask(*MF))
3046     MF->getRegInfo().addPhysRegsUsedFromRegMask(RegMask);
3047 
3048   LLT Ty = getLLTForType(*LP.getType(), *DL);
3049   Register Undef = MRI->createGenericVirtualRegister(Ty);
3050   MIRBuilder.buildUndef(Undef);
3051 
3052   SmallVector<LLT, 2> Tys;
3053   for (Type *Ty : cast<StructType>(LP.getType())->elements())
3054     Tys.push_back(getLLTForType(*Ty, *DL));
3055   assert(Tys.size() == 2 && "Only two-valued landingpads are supported");
3056 
3057   // Mark exception register as live in.
3058   Register ExceptionReg = TLI->getExceptionPointerRegister(PersonalityFn);
3059   if (!ExceptionReg)
3060     return false;
3061 
3062   MBB.addLiveIn(ExceptionReg);
3063   ArrayRef<Register> ResRegs = getOrCreateVRegs(LP);
3064   MIRBuilder.buildCopy(ResRegs[0], ExceptionReg);
3065 
3066   Register SelectorReg = TLI->getExceptionSelectorRegister(PersonalityFn);
3067   if (!SelectorReg)
3068     return false;
3069 
3070   MBB.addLiveIn(SelectorReg);
3071   Register PtrVReg = MRI->createGenericVirtualRegister(Tys[0]);
3072   MIRBuilder.buildCopy(PtrVReg, SelectorReg);
3073   MIRBuilder.buildCast(ResRegs[1], PtrVReg);
3074 
3075   return true;
3076 }
3077 
3078 bool IRTranslator::translateAlloca(const User &U,
3079                                    MachineIRBuilder &MIRBuilder) {
3080   auto &AI = cast<AllocaInst>(U);
3081 
3082   if (AI.isSwiftError())
3083     return true;
3084 
3085   if (AI.isStaticAlloca()) {
3086     Register Res = getOrCreateVReg(AI);
3087     int FI = getOrCreateFrameIndex(AI);
3088     MIRBuilder.buildFrameIndex(Res, FI);
3089     return true;
3090   }
3091 
3092   // FIXME: support stack probing for Windows.
3093   if (MF->getTarget().getTargetTriple().isOSWindows())
3094     return false;
3095 
3096   // Now we're in the harder dynamic case.
3097   Register NumElts = getOrCreateVReg(*AI.getArraySize());
3098   Type *IntPtrIRTy = DL->getIntPtrType(AI.getType());
3099   LLT IntPtrTy = getLLTForType(*IntPtrIRTy, *DL);
3100   if (MRI->getType(NumElts) != IntPtrTy) {
3101     Register ExtElts = MRI->createGenericVirtualRegister(IntPtrTy);
3102     MIRBuilder.buildZExtOrTrunc(ExtElts, NumElts);
3103     NumElts = ExtElts;
3104   }
3105 
3106   Type *Ty = AI.getAllocatedType();
3107 
3108   Register AllocSize = MRI->createGenericVirtualRegister(IntPtrTy);
3109   Register TySize =
3110       getOrCreateVReg(*ConstantInt::get(IntPtrIRTy, DL->getTypeAllocSize(Ty)));
3111   MIRBuilder.buildMul(AllocSize, NumElts, TySize);
3112 
3113   // Round the size of the allocation up to the stack alignment size
3114   // by add SA-1 to the size. This doesn't overflow because we're computing
3115   // an address inside an alloca.
3116   Align StackAlign = MF->getSubtarget().getFrameLowering()->getStackAlign();
3117   auto SAMinusOne = MIRBuilder.buildConstant(IntPtrTy, StackAlign.value() - 1);
3118   auto AllocAdd = MIRBuilder.buildAdd(IntPtrTy, AllocSize, SAMinusOne,
3119                                       MachineInstr::NoUWrap);
3120   auto AlignCst =
3121       MIRBuilder.buildConstant(IntPtrTy, ~(uint64_t)(StackAlign.value() - 1));
3122   auto AlignedAlloc = MIRBuilder.buildAnd(IntPtrTy, AllocAdd, AlignCst);
3123 
3124   Align Alignment = std::max(AI.getAlign(), DL->getPrefTypeAlign(Ty));
3125   if (Alignment <= StackAlign)
3126     Alignment = Align(1);
3127   MIRBuilder.buildDynStackAlloc(getOrCreateVReg(AI), AlignedAlloc, Alignment);
3128 
3129   MF->getFrameInfo().CreateVariableSizedObject(Alignment, &AI);
3130   assert(MF->getFrameInfo().hasVarSizedObjects());
3131   return true;
3132 }
3133 
3134 bool IRTranslator::translateVAArg(const User &U, MachineIRBuilder &MIRBuilder) {
3135   // FIXME: We may need more info about the type. Because of how LLT works,
3136   // we're completely discarding the i64/double distinction here (amongst
3137   // others). Fortunately the ABIs I know of where that matters don't use va_arg
3138   // anyway but that's not guaranteed.
3139   MIRBuilder.buildInstr(TargetOpcode::G_VAARG, {getOrCreateVReg(U)},
3140                         {getOrCreateVReg(*U.getOperand(0)),
3141                          DL->getABITypeAlign(U.getType()).value()});
3142   return true;
3143 }
3144 
3145 bool IRTranslator::translateUnreachable(const User &U,
3146                                         MachineIRBuilder &MIRBuilder) {
3147   auto &UI = cast<UnreachableInst>(U);
3148   if (!UI.shouldLowerToTrap(MF->getTarget().Options.TrapUnreachable,
3149                             MF->getTarget().Options.NoTrapAfterNoreturn))
3150     return true;
3151 
3152   MIRBuilder.buildTrap();
3153   return true;
3154 }
3155 
3156 bool IRTranslator::translateInsertElement(const User &U,
3157                                           MachineIRBuilder &MIRBuilder) {
3158   // If it is a <1 x Ty> vector, use the scalar as it is
3159   // not a legal vector type in LLT.
3160   if (auto *FVT = dyn_cast<FixedVectorType>(U.getType());
3161       FVT && FVT->getNumElements() == 1)
3162     return translateCopy(U, *U.getOperand(1), MIRBuilder);
3163 
3164   Register Res = getOrCreateVReg(U);
3165   Register Val = getOrCreateVReg(*U.getOperand(0));
3166   Register Elt = getOrCreateVReg(*U.getOperand(1));
3167   unsigned PreferredVecIdxWidth = TLI->getVectorIdxWidth(*DL);
3168   Register Idx;
3169   if (auto *CI = dyn_cast<ConstantInt>(U.getOperand(2))) {
3170     if (CI->getBitWidth() != PreferredVecIdxWidth) {
3171       APInt NewIdx = CI->getValue().zextOrTrunc(PreferredVecIdxWidth);
3172       auto *NewIdxCI = ConstantInt::get(CI->getContext(), NewIdx);
3173       Idx = getOrCreateVReg(*NewIdxCI);
3174     }
3175   }
3176   if (!Idx)
3177     Idx = getOrCreateVReg(*U.getOperand(2));
3178   if (MRI->getType(Idx).getSizeInBits() != PreferredVecIdxWidth) {
3179     const LLT VecIdxTy = LLT::scalar(PreferredVecIdxWidth);
3180     Idx = MIRBuilder.buildZExtOrTrunc(VecIdxTy, Idx).getReg(0);
3181   }
3182   MIRBuilder.buildInsertVectorElement(Res, Val, Elt, Idx);
3183   return true;
3184 }
3185 
3186 bool IRTranslator::translateInsertVector(const User &U,
3187                                          MachineIRBuilder &MIRBuilder) {
3188   Register Dst = getOrCreateVReg(U);
3189   Register Vec = getOrCreateVReg(*U.getOperand(0));
3190   Register Elt = getOrCreateVReg(*U.getOperand(1));
3191 
3192   ConstantInt *CI = cast<ConstantInt>(U.getOperand(2));
3193   unsigned PreferredVecIdxWidth = TLI->getVectorIdxWidth(*DL);
3194 
3195   // Resize Index to preferred index width.
3196   if (CI->getBitWidth() != PreferredVecIdxWidth) {
3197     APInt NewIdx = CI->getValue().zextOrTrunc(PreferredVecIdxWidth);
3198     CI = ConstantInt::get(CI->getContext(), NewIdx);
3199   }
3200 
3201   // If it is a <1 x Ty> vector, we have to use other means.
3202   if (auto *ResultType = dyn_cast<FixedVectorType>(U.getOperand(1)->getType());
3203       ResultType && ResultType->getNumElements() == 1) {
3204     if (auto *InputType = dyn_cast<FixedVectorType>(U.getOperand(0)->getType());
3205         InputType && InputType->getNumElements() == 1) {
3206       // We are inserting an illegal fixed vector into an illegal
3207       // fixed vector, use the scalar as it is not a legal vector type
3208       // in LLT.
3209       return translateCopy(U, *U.getOperand(0), MIRBuilder);
3210     }
3211     if (isa<FixedVectorType>(U.getOperand(0)->getType())) {
3212       // We are inserting an illegal fixed vector into a legal fixed
3213       // vector, use the scalar as it is not a legal vector type in
3214       // LLT.
3215       Register Idx = getOrCreateVReg(*CI);
3216       MIRBuilder.buildInsertVectorElement(Dst, Vec, Elt, Idx);
3217       return true;
3218     }
3219     if (isa<ScalableVectorType>(U.getOperand(0)->getType())) {
3220       // We are inserting an illegal fixed vector into a scalable
3221       // vector, use a scalar element insert.
3222       LLT VecIdxTy = LLT::scalar(PreferredVecIdxWidth);
3223       Register Idx = getOrCreateVReg(*CI);
3224       auto ScaledIndex = MIRBuilder.buildMul(
3225           VecIdxTy, MIRBuilder.buildVScale(VecIdxTy, 1), Idx);
3226       MIRBuilder.buildInsertVectorElement(Dst, Vec, Elt, ScaledIndex);
3227       return true;
3228     }
3229   }
3230 
3231   MIRBuilder.buildInsertSubvector(
3232       getOrCreateVReg(U), getOrCreateVReg(*U.getOperand(0)),
3233       getOrCreateVReg(*U.getOperand(1)), CI->getZExtValue());
3234   return true;
3235 }
3236 
3237 bool IRTranslator::translateExtractElement(const User &U,
3238                                            MachineIRBuilder &MIRBuilder) {
3239   // If it is a <1 x Ty> vector, use the scalar as it is
3240   // not a legal vector type in LLT.
3241   if (const FixedVectorType *FVT =
3242           dyn_cast<FixedVectorType>(U.getOperand(0)->getType()))
3243     if (FVT->getNumElements() == 1)
3244       return translateCopy(U, *U.getOperand(0), MIRBuilder);
3245 
3246   Register Res = getOrCreateVReg(U);
3247   Register Val = getOrCreateVReg(*U.getOperand(0));
3248   unsigned PreferredVecIdxWidth = TLI->getVectorIdxWidth(*DL);
3249   Register Idx;
3250   if (auto *CI = dyn_cast<ConstantInt>(U.getOperand(1))) {
3251     if (CI->getBitWidth() != PreferredVecIdxWidth) {
3252       APInt NewIdx = CI->getValue().zextOrTrunc(PreferredVecIdxWidth);
3253       auto *NewIdxCI = ConstantInt::get(CI->getContext(), NewIdx);
3254       Idx = getOrCreateVReg(*NewIdxCI);
3255     }
3256   }
3257   if (!Idx)
3258     Idx = getOrCreateVReg(*U.getOperand(1));
3259   if (MRI->getType(Idx).getSizeInBits() != PreferredVecIdxWidth) {
3260     const LLT VecIdxTy = LLT::scalar(PreferredVecIdxWidth);
3261     Idx = MIRBuilder.buildZExtOrTrunc(VecIdxTy, Idx).getReg(0);
3262   }
3263   MIRBuilder.buildExtractVectorElement(Res, Val, Idx);
3264   return true;
3265 }
3266 
3267 bool IRTranslator::translateExtractVector(const User &U,
3268                                           MachineIRBuilder &MIRBuilder) {
3269   Register Res = getOrCreateVReg(U);
3270   Register Vec = getOrCreateVReg(*U.getOperand(0));
3271   ConstantInt *CI = cast<ConstantInt>(U.getOperand(1));
3272   unsigned PreferredVecIdxWidth = TLI->getVectorIdxWidth(*DL);
3273 
3274   // Resize Index to preferred index width.
3275   if (CI->getBitWidth() != PreferredVecIdxWidth) {
3276     APInt NewIdx = CI->getValue().zextOrTrunc(PreferredVecIdxWidth);
3277     CI = ConstantInt::get(CI->getContext(), NewIdx);
3278   }
3279 
3280   // If it is a <1 x Ty> vector, we have to use other means.
3281   if (auto *ResultType = dyn_cast<FixedVectorType>(U.getType());
3282       ResultType && ResultType->getNumElements() == 1) {
3283     if (auto *InputType = dyn_cast<FixedVectorType>(U.getOperand(0)->getType());
3284         InputType && InputType->getNumElements() == 1) {
3285       // We are extracting an illegal fixed vector from an illegal fixed vector,
3286       // use the scalar as it is not a legal vector type in LLT.
3287       return translateCopy(U, *U.getOperand(0), MIRBuilder);
3288     }
3289     if (isa<FixedVectorType>(U.getOperand(0)->getType())) {
3290       // We are extracting an illegal fixed vector from a legal fixed
3291       // vector, use the scalar as it is not a legal vector type in
3292       // LLT.
3293       Register Idx = getOrCreateVReg(*CI);
3294       MIRBuilder.buildExtractVectorElement(Res, Vec, Idx);
3295       return true;
3296     }
3297     if (isa<ScalableVectorType>(U.getOperand(0)->getType())) {
3298       // We are extracting an illegal fixed vector from a scalable
3299       // vector, use a scalar element extract.
3300       LLT VecIdxTy = LLT::scalar(PreferredVecIdxWidth);
3301       Register Idx = getOrCreateVReg(*CI);
3302       auto ScaledIndex = MIRBuilder.buildMul(
3303           VecIdxTy, MIRBuilder.buildVScale(VecIdxTy, 1), Idx);
3304       MIRBuilder.buildExtractVectorElement(Res, Vec, ScaledIndex);
3305       return true;
3306     }
3307   }
3308 
3309   MIRBuilder.buildExtractSubvector(getOrCreateVReg(U),
3310                                    getOrCreateVReg(*U.getOperand(0)),
3311                                    CI->getZExtValue());
3312   return true;
3313 }
3314 
3315 bool IRTranslator::translateShuffleVector(const User &U,
3316                                           MachineIRBuilder &MIRBuilder) {
3317   // A ShuffleVector that operates on scalable vectors is a splat vector where
3318   // the value of the splat vector is the 0th element of the first operand,
3319   // since the index mask operand is the zeroinitializer (undef and
3320   // poison are treated as zeroinitializer here).
3321   if (U.getOperand(0)->getType()->isScalableTy()) {
3322     Register Val = getOrCreateVReg(*U.getOperand(0));
3323     auto SplatVal = MIRBuilder.buildExtractVectorElementConstant(
3324         MRI->getType(Val).getElementType(), Val, 0);
3325     MIRBuilder.buildSplatVector(getOrCreateVReg(U), SplatVal);
3326     return true;
3327   }
3328 
3329   ArrayRef<int> Mask;
3330   if (auto *SVI = dyn_cast<ShuffleVectorInst>(&U))
3331     Mask = SVI->getShuffleMask();
3332   else
3333     Mask = cast<ConstantExpr>(U).getShuffleMask();
3334   ArrayRef<int> MaskAlloc = MF->allocateShuffleMask(Mask);
3335   MIRBuilder
3336       .buildInstr(TargetOpcode::G_SHUFFLE_VECTOR, {getOrCreateVReg(U)},
3337                   {getOrCreateVReg(*U.getOperand(0)),
3338                    getOrCreateVReg(*U.getOperand(1))})
3339       .addShuffleMask(MaskAlloc);
3340   return true;
3341 }
3342 
3343 bool IRTranslator::translatePHI(const User &U, MachineIRBuilder &MIRBuilder) {
3344   const PHINode &PI = cast<PHINode>(U);
3345 
3346   SmallVector<MachineInstr *, 4> Insts;
3347   for (auto Reg : getOrCreateVRegs(PI)) {
3348     auto MIB = MIRBuilder.buildInstr(TargetOpcode::G_PHI, {Reg}, {});
3349     Insts.push_back(MIB.getInstr());
3350   }
3351 
3352   PendingPHIs.emplace_back(&PI, std::move(Insts));
3353   return true;
3354 }
3355 
3356 bool IRTranslator::translateAtomicCmpXchg(const User &U,
3357                                           MachineIRBuilder &MIRBuilder) {
3358   const AtomicCmpXchgInst &I = cast<AtomicCmpXchgInst>(U);
3359 
3360   auto Flags = TLI->getAtomicMemOperandFlags(I, *DL);
3361 
3362   auto Res = getOrCreateVRegs(I);
3363   Register OldValRes = Res[0];
3364   Register SuccessRes = Res[1];
3365   Register Addr = getOrCreateVReg(*I.getPointerOperand());
3366   Register Cmp = getOrCreateVReg(*I.getCompareOperand());
3367   Register NewVal = getOrCreateVReg(*I.getNewValOperand());
3368 
3369   MIRBuilder.buildAtomicCmpXchgWithSuccess(
3370       OldValRes, SuccessRes, Addr, Cmp, NewVal,
3371       *MF->getMachineMemOperand(
3372           MachinePointerInfo(I.getPointerOperand()), Flags, MRI->getType(Cmp),
3373           getMemOpAlign(I), I.getAAMetadata(), nullptr, I.getSyncScopeID(),
3374           I.getSuccessOrdering(), I.getFailureOrdering()));
3375   return true;
3376 }
3377 
3378 bool IRTranslator::translateAtomicRMW(const User &U,
3379                                       MachineIRBuilder &MIRBuilder) {
3380   if (containsBF16Type(U))
3381     return false;
3382 
3383   const AtomicRMWInst &I = cast<AtomicRMWInst>(U);
3384   auto Flags = TLI->getAtomicMemOperandFlags(I, *DL);
3385 
3386   Register Res = getOrCreateVReg(I);
3387   Register Addr = getOrCreateVReg(*I.getPointerOperand());
3388   Register Val = getOrCreateVReg(*I.getValOperand());
3389 
3390   unsigned Opcode = 0;
3391   switch (I.getOperation()) {
3392   default:
3393     return false;
3394   case AtomicRMWInst::Xchg:
3395     Opcode = TargetOpcode::G_ATOMICRMW_XCHG;
3396     break;
3397   case AtomicRMWInst::Add:
3398     Opcode = TargetOpcode::G_ATOMICRMW_ADD;
3399     break;
3400   case AtomicRMWInst::Sub:
3401     Opcode = TargetOpcode::G_ATOMICRMW_SUB;
3402     break;
3403   case AtomicRMWInst::And:
3404     Opcode = TargetOpcode::G_ATOMICRMW_AND;
3405     break;
3406   case AtomicRMWInst::Nand:
3407     Opcode = TargetOpcode::G_ATOMICRMW_NAND;
3408     break;
3409   case AtomicRMWInst::Or:
3410     Opcode = TargetOpcode::G_ATOMICRMW_OR;
3411     break;
3412   case AtomicRMWInst::Xor:
3413     Opcode = TargetOpcode::G_ATOMICRMW_XOR;
3414     break;
3415   case AtomicRMWInst::Max:
3416     Opcode = TargetOpcode::G_ATOMICRMW_MAX;
3417     break;
3418   case AtomicRMWInst::Min:
3419     Opcode = TargetOpcode::G_ATOMICRMW_MIN;
3420     break;
3421   case AtomicRMWInst::UMax:
3422     Opcode = TargetOpcode::G_ATOMICRMW_UMAX;
3423     break;
3424   case AtomicRMWInst::UMin:
3425     Opcode = TargetOpcode::G_ATOMICRMW_UMIN;
3426     break;
3427   case AtomicRMWInst::FAdd:
3428     Opcode = TargetOpcode::G_ATOMICRMW_FADD;
3429     break;
3430   case AtomicRMWInst::FSub:
3431     Opcode = TargetOpcode::G_ATOMICRMW_FSUB;
3432     break;
3433   case AtomicRMWInst::FMax:
3434     Opcode = TargetOpcode::G_ATOMICRMW_FMAX;
3435     break;
3436   case AtomicRMWInst::FMin:
3437     Opcode = TargetOpcode::G_ATOMICRMW_FMIN;
3438     break;
3439   case AtomicRMWInst::FMaximum:
3440     Opcode = TargetOpcode::G_ATOMICRMW_FMAXIMUM;
3441     break;
3442   case AtomicRMWInst::FMinimum:
3443     Opcode = TargetOpcode::G_ATOMICRMW_FMINIMUM;
3444     break;
3445   case AtomicRMWInst::UIncWrap:
3446     Opcode = TargetOpcode::G_ATOMICRMW_UINC_WRAP;
3447     break;
3448   case AtomicRMWInst::UDecWrap:
3449     Opcode = TargetOpcode::G_ATOMICRMW_UDEC_WRAP;
3450     break;
3451   case AtomicRMWInst::USubCond:
3452     Opcode = TargetOpcode::G_ATOMICRMW_USUB_COND;
3453     break;
3454   case AtomicRMWInst::USubSat:
3455     Opcode = TargetOpcode::G_ATOMICRMW_USUB_SAT;
3456     break;
3457   }
3458 
3459   MIRBuilder.buildAtomicRMW(
3460       Opcode, Res, Addr, Val,
3461       *MF->getMachineMemOperand(MachinePointerInfo(I.getPointerOperand()),
3462                                 Flags, MRI->getType(Val), getMemOpAlign(I),
3463                                 I.getAAMetadata(), nullptr, I.getSyncScopeID(),
3464                                 I.getOrdering()));
3465   return true;
3466 }
3467 
3468 bool IRTranslator::translateFence(const User &U,
3469                                   MachineIRBuilder &MIRBuilder) {
3470   const FenceInst &Fence = cast<FenceInst>(U);
3471   MIRBuilder.buildFence(static_cast<unsigned>(Fence.getOrdering()),
3472                         Fence.getSyncScopeID());
3473   return true;
3474 }
3475 
3476 bool IRTranslator::translateFreeze(const User &U,
3477                                    MachineIRBuilder &MIRBuilder) {
3478   const ArrayRef<Register> DstRegs = getOrCreateVRegs(U);
3479   const ArrayRef<Register> SrcRegs = getOrCreateVRegs(*U.getOperand(0));
3480 
3481   assert(DstRegs.size() == SrcRegs.size() &&
3482          "Freeze with different source and destination type?");
3483 
3484   for (unsigned I = 0; I < DstRegs.size(); ++I) {
3485     MIRBuilder.buildFreeze(DstRegs[I], SrcRegs[I]);
3486   }
3487 
3488   return true;
3489 }
3490 
3491 void IRTranslator::finishPendingPhis() {
3492 #ifndef NDEBUG
3493   DILocationVerifier Verifier;
3494   GISelObserverWrapper WrapperObserver(&Verifier);
3495   RAIIMFObsDelInstaller ObsInstall(*MF, WrapperObserver);
3496 #endif // ifndef NDEBUG
3497   for (auto &Phi : PendingPHIs) {
3498     const PHINode *PI = Phi.first;
3499     if (PI->getType()->isEmptyTy())
3500       continue;
3501     ArrayRef<MachineInstr *> ComponentPHIs = Phi.second;
3502     MachineBasicBlock *PhiMBB = ComponentPHIs[0]->getParent();
3503     EntryBuilder->setDebugLoc(PI->getDebugLoc());
3504 #ifndef NDEBUG
3505     Verifier.setCurrentInst(PI);
3506 #endif // ifndef NDEBUG
3507 
3508     SmallSet<const MachineBasicBlock *, 16> SeenPreds;
3509     for (unsigned i = 0; i < PI->getNumIncomingValues(); ++i) {
3510       auto IRPred = PI->getIncomingBlock(i);
3511       ArrayRef<Register> ValRegs = getOrCreateVRegs(*PI->getIncomingValue(i));
3512       for (auto *Pred : getMachinePredBBs({IRPred, PI->getParent()})) {
3513         if (SeenPreds.count(Pred) || !PhiMBB->isPredecessor(Pred))
3514           continue;
3515         SeenPreds.insert(Pred);
3516         for (unsigned j = 0; j < ValRegs.size(); ++j) {
3517           MachineInstrBuilder MIB(*MF, ComponentPHIs[j]);
3518           MIB.addUse(ValRegs[j]);
3519           MIB.addMBB(Pred);
3520         }
3521       }
3522     }
3523   }
3524 }
3525 
3526 void IRTranslator::translateDbgValueRecord(Value *V, bool HasArgList,
3527                                      const DILocalVariable *Variable,
3528                                      const DIExpression *Expression,
3529                                      const DebugLoc &DL,
3530                                      MachineIRBuilder &MIRBuilder) {
3531   assert(Variable->isValidLocationForIntrinsic(DL) &&
3532          "Expected inlined-at fields to agree");
3533   // Act as if we're handling a debug intrinsic.
3534   MIRBuilder.setDebugLoc(DL);
3535 
3536   if (!V || HasArgList) {
3537     // DI cannot produce a valid DBG_VALUE, so produce an undef DBG_VALUE to
3538     // terminate any prior location.
3539     MIRBuilder.buildIndirectDbgValue(0, Variable, Expression);
3540     return;
3541   }
3542 
3543   if (const auto *CI = dyn_cast<Constant>(V)) {
3544     MIRBuilder.buildConstDbgValue(*CI, Variable, Expression);
3545     return;
3546   }
3547 
3548   if (auto *AI = dyn_cast<AllocaInst>(V);
3549       AI && AI->isStaticAlloca() && Expression->startsWithDeref()) {
3550     // If the value is an alloca and the expression starts with a
3551     // dereference, track a stack slot instead of a register, as registers
3552     // may be clobbered.
3553     auto ExprOperands = Expression->getElements();
3554     auto *ExprDerefRemoved =
3555         DIExpression::get(AI->getContext(), ExprOperands.drop_front());
3556     MIRBuilder.buildFIDbgValue(getOrCreateFrameIndex(*AI), Variable,
3557                                ExprDerefRemoved);
3558     return;
3559   }
3560   if (translateIfEntryValueArgument(false, V, Variable, Expression, DL,
3561                                     MIRBuilder))
3562     return;
3563   for (Register Reg : getOrCreateVRegs(*V)) {
3564     // FIXME: This does not handle register-indirect values at offset 0. The
3565     // direct/indirect thing shouldn't really be handled by something as
3566     // implicit as reg+noreg vs reg+imm in the first place, but it seems
3567     // pretty baked in right now.
3568     MIRBuilder.buildDirectDbgValue(Reg, Variable, Expression);
3569   }
3570 }
3571 
3572 void IRTranslator::translateDbgDeclareRecord(Value *Address, bool HasArgList,
3573                                      const DILocalVariable *Variable,
3574                                      const DIExpression *Expression,
3575                                      const DebugLoc &DL,
3576                                      MachineIRBuilder &MIRBuilder) {
3577   if (!Address || isa<UndefValue>(Address)) {
3578     LLVM_DEBUG(dbgs() << "Dropping debug info for " << *Variable << "\n");
3579     return;
3580   }
3581 
3582   assert(Variable->isValidLocationForIntrinsic(DL) &&
3583          "Expected inlined-at fields to agree");
3584   auto AI = dyn_cast<AllocaInst>(Address);
3585   if (AI && AI->isStaticAlloca()) {
3586     // Static allocas are tracked at the MF level, no need for DBG_VALUE
3587     // instructions (in fact, they get ignored if they *do* exist).
3588     MF->setVariableDbgInfo(Variable, Expression,
3589                            getOrCreateFrameIndex(*AI), DL);
3590     return;
3591   }
3592 
3593   if (translateIfEntryValueArgument(true, Address, Variable,
3594                                     Expression, DL,
3595                                     MIRBuilder))
3596     return;
3597 
3598   // A dbg.declare describes the address of a source variable, so lower it
3599   // into an indirect DBG_VALUE.
3600   MIRBuilder.setDebugLoc(DL);
3601   MIRBuilder.buildIndirectDbgValue(getOrCreateVReg(*Address), Variable,
3602                                    Expression);
3603 }
3604 
3605 void IRTranslator::translateDbgInfo(const Instruction &Inst,
3606                                       MachineIRBuilder &MIRBuilder) {
3607   for (DbgRecord &DR : Inst.getDbgRecordRange()) {
3608     if (DbgLabelRecord *DLR = dyn_cast<DbgLabelRecord>(&DR)) {
3609       MIRBuilder.setDebugLoc(DLR->getDebugLoc());
3610       assert(DLR->getLabel() && "Missing label");
3611       assert(DLR->getLabel()->isValidLocationForIntrinsic(
3612                  MIRBuilder.getDebugLoc()) &&
3613              "Expected inlined-at fields to agree");
3614       MIRBuilder.buildDbgLabel(DLR->getLabel());
3615       continue;
3616     }
3617     DbgVariableRecord &DVR = cast<DbgVariableRecord>(DR);
3618     const DILocalVariable *Variable = DVR.getVariable();
3619     const DIExpression *Expression = DVR.getExpression();
3620     Value *V = DVR.getVariableLocationOp(0);
3621     if (DVR.isDbgDeclare())
3622       translateDbgDeclareRecord(V, DVR.hasArgList(), Variable, Expression,
3623                                 DVR.getDebugLoc(), MIRBuilder);
3624     else
3625       translateDbgValueRecord(V, DVR.hasArgList(), Variable, Expression,
3626                               DVR.getDebugLoc(), MIRBuilder);
3627   }
3628 }
3629 
3630 bool IRTranslator::translate(const Instruction &Inst) {
3631   CurBuilder->setDebugLoc(Inst.getDebugLoc());
3632   CurBuilder->setPCSections(Inst.getMetadata(LLVMContext::MD_pcsections));
3633   CurBuilder->setMMRAMetadata(Inst.getMetadata(LLVMContext::MD_mmra));
3634 
3635   if (TLI->fallBackToDAGISel(Inst))
3636     return false;
3637 
3638   switch (Inst.getOpcode()) {
3639 #define HANDLE_INST(NUM, OPCODE, CLASS)                                        \
3640   case Instruction::OPCODE:                                                    \
3641     return translate##OPCODE(Inst, *CurBuilder.get());
3642 #include "llvm/IR/Instruction.def"
3643   default:
3644     return false;
3645   }
3646 }
3647 
3648 bool IRTranslator::translate(const Constant &C, Register Reg) {
3649   // We only emit constants into the entry block from here. To prevent jumpy
3650   // debug behaviour remove debug line.
3651   if (auto CurrInstDL = CurBuilder->getDL())
3652     EntryBuilder->setDebugLoc(DebugLoc());
3653 
3654   if (auto CI = dyn_cast<ConstantInt>(&C)) {
3655     // buildConstant expects a to-be-splatted scalar ConstantInt.
3656     if (isa<VectorType>(CI->getType()))
3657       CI = ConstantInt::get(CI->getContext(), CI->getValue());
3658     EntryBuilder->buildConstant(Reg, *CI);
3659   } else if (auto CF = dyn_cast<ConstantFP>(&C)) {
3660     // buildFConstant expects a to-be-splatted scalar ConstantFP.
3661     if (isa<VectorType>(CF->getType()))
3662       CF = ConstantFP::get(CF->getContext(), CF->getValue());
3663     EntryBuilder->buildFConstant(Reg, *CF);
3664   } else if (isa<UndefValue>(C))
3665     EntryBuilder->buildUndef(Reg);
3666   else if (isa<ConstantPointerNull>(C))
3667     EntryBuilder->buildConstant(Reg, 0);
3668   else if (auto GV = dyn_cast<GlobalValue>(&C))
3669     EntryBuilder->buildGlobalValue(Reg, GV);
3670   else if (auto CPA = dyn_cast<ConstantPtrAuth>(&C)) {
3671     Register Addr = getOrCreateVReg(*CPA->getPointer());
3672     Register AddrDisc = getOrCreateVReg(*CPA->getAddrDiscriminator());
3673     EntryBuilder->buildConstantPtrAuth(Reg, CPA, Addr, AddrDisc);
3674   } else if (auto CAZ = dyn_cast<ConstantAggregateZero>(&C)) {
3675     Constant &Elt = *CAZ->getElementValue(0u);
3676     if (isa<ScalableVectorType>(CAZ->getType())) {
3677       EntryBuilder->buildSplatVector(Reg, getOrCreateVReg(Elt));
3678       return true;
3679     }
3680     // Return the scalar if it is a <1 x Ty> vector.
3681     unsigned NumElts = CAZ->getElementCount().getFixedValue();
3682     if (NumElts == 1)
3683       return translateCopy(C, Elt, *EntryBuilder);
3684     // All elements are zero so we can just use the first one.
3685     EntryBuilder->buildSplatBuildVector(Reg, getOrCreateVReg(Elt));
3686   } else if (auto CV = dyn_cast<ConstantDataVector>(&C)) {
3687     // Return the scalar if it is a <1 x Ty> vector.
3688     if (CV->getNumElements() == 1)
3689       return translateCopy(C, *CV->getElementAsConstant(0), *EntryBuilder);
3690     SmallVector<Register, 4> Ops;
3691     for (unsigned i = 0; i < CV->getNumElements(); ++i) {
3692       Constant &Elt = *CV->getElementAsConstant(i);
3693       Ops.push_back(getOrCreateVReg(Elt));
3694     }
3695     EntryBuilder->buildBuildVector(Reg, Ops);
3696   } else if (auto CE = dyn_cast<ConstantExpr>(&C)) {
3697     switch(CE->getOpcode()) {
3698 #define HANDLE_INST(NUM, OPCODE, CLASS)                                        \
3699   case Instruction::OPCODE:                                                    \
3700     return translate##OPCODE(*CE, *EntryBuilder.get());
3701 #include "llvm/IR/Instruction.def"
3702     default:
3703       return false;
3704     }
3705   } else if (auto CV = dyn_cast<ConstantVector>(&C)) {
3706     if (CV->getNumOperands() == 1)
3707       return translateCopy(C, *CV->getOperand(0), *EntryBuilder);
3708     SmallVector<Register, 4> Ops;
3709     for (unsigned i = 0; i < CV->getNumOperands(); ++i) {
3710       Ops.push_back(getOrCreateVReg(*CV->getOperand(i)));
3711     }
3712     EntryBuilder->buildBuildVector(Reg, Ops);
3713   } else if (auto *BA = dyn_cast<BlockAddress>(&C)) {
3714     EntryBuilder->buildBlockAddress(Reg, BA);
3715   } else
3716     return false;
3717 
3718   return true;
3719 }
3720 
3721 bool IRTranslator::finalizeBasicBlock(const BasicBlock &BB,
3722                                       MachineBasicBlock &MBB) {
3723   for (auto &BTB : SL->BitTestCases) {
3724     // Emit header first, if it wasn't already emitted.
3725     if (!BTB.Emitted)
3726       emitBitTestHeader(BTB, BTB.Parent);
3727 
3728     BranchProbability UnhandledProb = BTB.Prob;
3729     for (unsigned j = 0, ej = BTB.Cases.size(); j != ej; ++j) {
3730       UnhandledProb -= BTB.Cases[j].ExtraProb;
3731       // Set the current basic block to the mbb we wish to insert the code into
3732       MachineBasicBlock *MBB = BTB.Cases[j].ThisBB;
3733       // If all cases cover a contiguous range, it is not necessary to jump to
3734       // the default block after the last bit test fails. This is because the
3735       // range check during bit test header creation has guaranteed that every
3736       // case here doesn't go outside the range. In this case, there is no need
3737       // to perform the last bit test, as it will always be true. Instead, make
3738       // the second-to-last bit-test fall through to the target of the last bit
3739       // test, and delete the last bit test.
3740 
3741       MachineBasicBlock *NextMBB;
3742       if ((BTB.ContiguousRange || BTB.FallthroughUnreachable) && j + 2 == ej) {
3743         // Second-to-last bit-test with contiguous range: fall through to the
3744         // target of the final bit test.
3745         NextMBB = BTB.Cases[j + 1].TargetBB;
3746       } else if (j + 1 == ej) {
3747         // For the last bit test, fall through to Default.
3748         NextMBB = BTB.Default;
3749       } else {
3750         // Otherwise, fall through to the next bit test.
3751         NextMBB = BTB.Cases[j + 1].ThisBB;
3752       }
3753 
3754       emitBitTestCase(BTB, NextMBB, UnhandledProb, BTB.Reg, BTB.Cases[j], MBB);
3755 
3756       if ((BTB.ContiguousRange || BTB.FallthroughUnreachable) && j + 2 == ej) {
3757         // We need to record the replacement phi edge here that normally
3758         // happens in emitBitTestCase before we delete the case, otherwise the
3759         // phi edge will be lost.
3760         addMachineCFGPred({BTB.Parent->getBasicBlock(),
3761                            BTB.Cases[ej - 1].TargetBB->getBasicBlock()},
3762                           MBB);
3763         // Since we're not going to use the final bit test, remove it.
3764         BTB.Cases.pop_back();
3765         break;
3766       }
3767     }
3768     // This is "default" BB. We have two jumps to it. From "header" BB and from
3769     // last "case" BB, unless the latter was skipped.
3770     CFGEdge HeaderToDefaultEdge = {BTB.Parent->getBasicBlock(),
3771                                    BTB.Default->getBasicBlock()};
3772     addMachineCFGPred(HeaderToDefaultEdge, BTB.Parent);
3773     if (!BTB.ContiguousRange) {
3774       addMachineCFGPred(HeaderToDefaultEdge, BTB.Cases.back().ThisBB);
3775     }
3776   }
3777   SL->BitTestCases.clear();
3778 
3779   for (auto &JTCase : SL->JTCases) {
3780     // Emit header first, if it wasn't already emitted.
3781     if (!JTCase.first.Emitted)
3782       emitJumpTableHeader(JTCase.second, JTCase.first, JTCase.first.HeaderBB);
3783 
3784     emitJumpTable(JTCase.second, JTCase.second.MBB);
3785   }
3786   SL->JTCases.clear();
3787 
3788   for (auto &SwCase : SL->SwitchCases)
3789     emitSwitchCase(SwCase, &CurBuilder->getMBB(), *CurBuilder);
3790   SL->SwitchCases.clear();
3791 
3792   // Check if we need to generate stack-protector guard checks.
3793   StackProtector &SP = getAnalysis<StackProtector>();
3794   if (SP.shouldEmitSDCheck(BB)) {
3795     bool FunctionBasedInstrumentation =
3796         TLI->getSSPStackGuardCheck(*MF->getFunction().getParent());
3797     SPDescriptor.initialize(&BB, &MBB, FunctionBasedInstrumentation);
3798   }
3799   // Handle stack protector.
3800   if (SPDescriptor.shouldEmitFunctionBasedCheckStackProtector()) {
3801     LLVM_DEBUG(dbgs() << "Unimplemented stack protector case\n");
3802     return false;
3803   } else if (SPDescriptor.shouldEmitStackProtector()) {
3804     MachineBasicBlock *ParentMBB = SPDescriptor.getParentMBB();
3805     MachineBasicBlock *SuccessMBB = SPDescriptor.getSuccessMBB();
3806 
3807     // Find the split point to split the parent mbb. At the same time copy all
3808     // physical registers used in the tail of parent mbb into virtual registers
3809     // before the split point and back into physical registers after the split
3810     // point. This prevents us needing to deal with Live-ins and many other
3811     // register allocation issues caused by us splitting the parent mbb. The
3812     // register allocator will clean up said virtual copies later on.
3813     MachineBasicBlock::iterator SplitPoint = findSplitPointForStackProtector(
3814         ParentMBB, *MF->getSubtarget().getInstrInfo());
3815 
3816     // Splice the terminator of ParentMBB into SuccessMBB.
3817     SuccessMBB->splice(SuccessMBB->end(), ParentMBB, SplitPoint,
3818                        ParentMBB->end());
3819 
3820     // Add compare/jump on neq/jump to the parent BB.
3821     if (!emitSPDescriptorParent(SPDescriptor, ParentMBB))
3822       return false;
3823 
3824     // CodeGen Failure MBB if we have not codegened it yet.
3825     MachineBasicBlock *FailureMBB = SPDescriptor.getFailureMBB();
3826     if (FailureMBB->empty()) {
3827       if (!emitSPDescriptorFailure(SPDescriptor, FailureMBB))
3828         return false;
3829     }
3830 
3831     // Clear the Per-BB State.
3832     SPDescriptor.resetPerBBState();
3833   }
3834   return true;
3835 }
3836 
3837 bool IRTranslator::emitSPDescriptorParent(StackProtectorDescriptor &SPD,
3838                                           MachineBasicBlock *ParentBB) {
3839   CurBuilder->setInsertPt(*ParentBB, ParentBB->end());
3840   // First create the loads to the guard/stack slot for the comparison.
3841   Type *PtrIRTy = PointerType::getUnqual(MF->getFunction().getContext());
3842   const LLT PtrTy = getLLTForType(*PtrIRTy, *DL);
3843   LLT PtrMemTy = getLLTForMVT(TLI->getPointerMemTy(*DL));
3844 
3845   MachineFrameInfo &MFI = ParentBB->getParent()->getFrameInfo();
3846   int FI = MFI.getStackProtectorIndex();
3847 
3848   Register Guard;
3849   Register StackSlotPtr = CurBuilder->buildFrameIndex(PtrTy, FI).getReg(0);
3850   const Module &M = *ParentBB->getParent()->getFunction().getParent();
3851   Align Align = DL->getPrefTypeAlign(PointerType::getUnqual(M.getContext()));
3852 
3853   // Generate code to load the content of the guard slot.
3854   Register GuardVal =
3855       CurBuilder
3856           ->buildLoad(PtrMemTy, StackSlotPtr,
3857                       MachinePointerInfo::getFixedStack(*MF, FI), Align,
3858                       MachineMemOperand::MOLoad | MachineMemOperand::MOVolatile)
3859           .getReg(0);
3860 
3861   if (TLI->useStackGuardXorFP()) {
3862     LLVM_DEBUG(dbgs() << "Stack protector xor'ing with FP not yet implemented");
3863     return false;
3864   }
3865 
3866   // Retrieve guard check function, nullptr if instrumentation is inlined.
3867   if (const Function *GuardCheckFn = TLI->getSSPStackGuardCheck(M)) {
3868     // This path is currently untestable on GlobalISel, since the only platform
3869     // that needs this seems to be Windows, and we fall back on that currently.
3870     // The code still lives here in case that changes.
3871     // Silence warning about unused variable until the code below that uses
3872     // 'GuardCheckFn' is enabled.
3873     (void)GuardCheckFn;
3874     return false;
3875 #if 0
3876     // The target provides a guard check function to validate the guard value.
3877     // Generate a call to that function with the content of the guard slot as
3878     // argument.
3879     FunctionType *FnTy = GuardCheckFn->getFunctionType();
3880     assert(FnTy->getNumParams() == 1 && "Invalid function signature");
3881     ISD::ArgFlagsTy Flags;
3882     if (GuardCheckFn->hasAttribute(1, Attribute::AttrKind::InReg))
3883       Flags.setInReg();
3884     CallLowering::ArgInfo GuardArgInfo(
3885         {GuardVal, FnTy->getParamType(0), {Flags}});
3886 
3887     CallLowering::CallLoweringInfo Info;
3888     Info.OrigArgs.push_back(GuardArgInfo);
3889     Info.CallConv = GuardCheckFn->getCallingConv();
3890     Info.Callee = MachineOperand::CreateGA(GuardCheckFn, 0);
3891     Info.OrigRet = {Register(), FnTy->getReturnType()};
3892     if (!CLI->lowerCall(MIRBuilder, Info)) {
3893       LLVM_DEBUG(dbgs() << "Failed to lower call to stack protector check\n");
3894       return false;
3895     }
3896     return true;
3897 #endif
3898   }
3899 
3900   // If useLoadStackGuardNode returns true, generate LOAD_STACK_GUARD.
3901   // Otherwise, emit a volatile load to retrieve the stack guard value.
3902   if (TLI->useLoadStackGuardNode(*ParentBB->getBasicBlock()->getModule())) {
3903     Guard =
3904         MRI->createGenericVirtualRegister(LLT::scalar(PtrTy.getSizeInBits()));
3905     getStackGuard(Guard, *CurBuilder);
3906   } else {
3907     // TODO: test using android subtarget when we support @llvm.thread.pointer.
3908     const Value *IRGuard = TLI->getSDagStackGuard(M);
3909     Register GuardPtr = getOrCreateVReg(*IRGuard);
3910 
3911     Guard = CurBuilder
3912                 ->buildLoad(PtrMemTy, GuardPtr,
3913                             MachinePointerInfo::getFixedStack(*MF, FI), Align,
3914                             MachineMemOperand::MOLoad |
3915                                 MachineMemOperand::MOVolatile)
3916                 .getReg(0);
3917   }
3918 
3919   // Perform the comparison.
3920   auto Cmp =
3921       CurBuilder->buildICmp(CmpInst::ICMP_NE, LLT::scalar(1), Guard, GuardVal);
3922   // If the guard/stackslot do not equal, branch to failure MBB.
3923   CurBuilder->buildBrCond(Cmp, *SPD.getFailureMBB());
3924   // Otherwise branch to success MBB.
3925   CurBuilder->buildBr(*SPD.getSuccessMBB());
3926   return true;
3927 }
3928 
3929 bool IRTranslator::emitSPDescriptorFailure(StackProtectorDescriptor &SPD,
3930                                            MachineBasicBlock *FailureBB) {
3931   CurBuilder->setInsertPt(*FailureBB, FailureBB->end());
3932 
3933   const RTLIB::Libcall Libcall = RTLIB::STACKPROTECTOR_CHECK_FAIL;
3934   const char *Name = TLI->getLibcallName(Libcall);
3935 
3936   CallLowering::CallLoweringInfo Info;
3937   Info.CallConv = TLI->getLibcallCallingConv(Libcall);
3938   Info.Callee = MachineOperand::CreateES(Name);
3939   Info.OrigRet = {Register(), Type::getVoidTy(MF->getFunction().getContext()),
3940                   0};
3941   if (!CLI->lowerCall(*CurBuilder, Info)) {
3942     LLVM_DEBUG(dbgs() << "Failed to lower call to stack protector fail\n");
3943     return false;
3944   }
3945 
3946   // Emit a trap instruction if we are required to do so.
3947   const TargetOptions &TargetOpts = TLI->getTargetMachine().Options;
3948   if (TargetOpts.TrapUnreachable && !TargetOpts.NoTrapAfterNoreturn)
3949     CurBuilder->buildInstr(TargetOpcode::G_TRAP);
3950 
3951   return true;
3952 }
3953 
3954 void IRTranslator::finalizeFunction() {
3955   // Release the memory used by the different maps we
3956   // needed during the translation.
3957   PendingPHIs.clear();
3958   VMap.reset();
3959   FrameIndices.clear();
3960   MachinePreds.clear();
3961   // MachineIRBuilder::DebugLoc can outlive the DILocation it holds. Clear it
3962   // to avoid accessing free’d memory (in runOnMachineFunction) and to avoid
3963   // destroying it twice (in ~IRTranslator() and ~LLVMContext())
3964   EntryBuilder.reset();
3965   CurBuilder.reset();
3966   FuncInfo.clear();
3967   SPDescriptor.resetPerFunctionState();
3968 }
3969 
3970 /// Returns true if a BasicBlock \p BB within a variadic function contains a
3971 /// variadic musttail call.
3972 static bool checkForMustTailInVarArgFn(bool IsVarArg, const BasicBlock &BB) {
3973   if (!IsVarArg)
3974     return false;
3975 
3976   // Walk the block backwards, because tail calls usually only appear at the end
3977   // of a block.
3978   return llvm::any_of(llvm::reverse(BB), [](const Instruction &I) {
3979     const auto *CI = dyn_cast<CallInst>(&I);
3980     return CI && CI->isMustTailCall();
3981   });
3982 }
3983 
3984 bool IRTranslator::runOnMachineFunction(MachineFunction &CurMF) {
3985   MF = &CurMF;
3986   const Function &F = MF->getFunction();
3987   GISelCSEAnalysisWrapper &Wrapper =
3988       getAnalysis<GISelCSEAnalysisWrapperPass>().getCSEWrapper();
3989   // Set the CSEConfig and run the analysis.
3990   GISelCSEInfo *CSEInfo = nullptr;
3991   TPC = &getAnalysis<TargetPassConfig>();
3992   bool EnableCSE = EnableCSEInIRTranslator.getNumOccurrences()
3993                        ? EnableCSEInIRTranslator
3994                        : TPC->isGISelCSEEnabled();
3995   TLI = MF->getSubtarget().getTargetLowering();
3996 
3997   if (EnableCSE) {
3998     EntryBuilder = std::make_unique<CSEMIRBuilder>(CurMF);
3999     CSEInfo = &Wrapper.get(TPC->getCSEConfig());
4000     EntryBuilder->setCSEInfo(CSEInfo);
4001     CurBuilder = std::make_unique<CSEMIRBuilder>(CurMF);
4002     CurBuilder->setCSEInfo(CSEInfo);
4003   } else {
4004     EntryBuilder = std::make_unique<MachineIRBuilder>();
4005     CurBuilder = std::make_unique<MachineIRBuilder>();
4006   }
4007   CLI = MF->getSubtarget().getCallLowering();
4008   CurBuilder->setMF(*MF);
4009   EntryBuilder->setMF(*MF);
4010   MRI = &MF->getRegInfo();
4011   DL = &F.getDataLayout();
4012   ORE = std::make_unique<OptimizationRemarkEmitter>(&F);
4013   const TargetMachine &TM = MF->getTarget();
4014   TM.resetTargetOptions(F);
4015   EnableOpts = OptLevel != CodeGenOptLevel::None && !skipFunction(F);
4016   FuncInfo.MF = MF;
4017   if (EnableOpts) {
4018     AA = &getAnalysis<AAResultsWrapperPass>().getAAResults();
4019     FuncInfo.BPI = &getAnalysis<BranchProbabilityInfoWrapperPass>().getBPI();
4020   } else {
4021     AA = nullptr;
4022     FuncInfo.BPI = nullptr;
4023   }
4024 
4025   AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(
4026       MF->getFunction());
4027   LibInfo = &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI(F);
4028   FuncInfo.CanLowerReturn = CLI->checkReturnTypeForCallConv(*MF);
4029 
4030   SL = std::make_unique<GISelSwitchLowering>(this, FuncInfo);
4031   SL->init(*TLI, TM, *DL);
4032 
4033   assert(PendingPHIs.empty() && "stale PHIs");
4034 
4035   // Targets which want to use big endian can enable it using
4036   // enableBigEndian()
4037   if (!DL->isLittleEndian() && !CLI->enableBigEndian()) {
4038     // Currently we don't properly handle big endian code.
4039     OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
4040                                F.getSubprogram(), &F.getEntryBlock());
4041     R << "unable to translate in big endian mode";
4042     reportTranslationError(*MF, *TPC, *ORE, R);
4043     return false;
4044   }
4045 
4046   // Release the per-function state when we return, whether we succeeded or not.
4047   auto FinalizeOnReturn = make_scope_exit([this]() { finalizeFunction(); });
4048 
4049   // Setup a separate basic-block for the arguments and constants
4050   MachineBasicBlock *EntryBB = MF->CreateMachineBasicBlock();
4051   MF->push_back(EntryBB);
4052   EntryBuilder->setMBB(*EntryBB);
4053 
4054   DebugLoc DbgLoc = F.getEntryBlock().getFirstNonPHIIt()->getDebugLoc();
4055   SwiftError.setFunction(CurMF);
4056   SwiftError.createEntriesInEntryBlock(DbgLoc);
4057 
4058   bool IsVarArg = F.isVarArg();
4059   bool HasMustTailInVarArgFn = false;
4060 
4061   // Create all blocks, in IR order, to preserve the layout.
4062   FuncInfo.MBBMap.resize(F.getMaxBlockNumber());
4063   for (const BasicBlock &BB: F) {
4064     auto *&MBB = FuncInfo.MBBMap[BB.getNumber()];
4065 
4066     MBB = MF->CreateMachineBasicBlock(&BB);
4067     MF->push_back(MBB);
4068 
4069     if (BB.hasAddressTaken())
4070       MBB->setAddressTakenIRBlock(const_cast<BasicBlock *>(&BB));
4071 
4072     if (!HasMustTailInVarArgFn)
4073       HasMustTailInVarArgFn = checkForMustTailInVarArgFn(IsVarArg, BB);
4074   }
4075 
4076   MF->getFrameInfo().setHasMustTailInVarArgFunc(HasMustTailInVarArgFn);
4077 
4078   // Make our arguments/constants entry block fallthrough to the IR entry block.
4079   EntryBB->addSuccessor(&getMBB(F.front()));
4080 
4081   if (CLI->fallBackToDAGISel(*MF)) {
4082     OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
4083                                F.getSubprogram(), &F.getEntryBlock());
4084     R << "unable to lower function: "
4085       << ore::NV("Prototype", F.getFunctionType());
4086     reportTranslationError(*MF, *TPC, *ORE, R);
4087     return false;
4088   }
4089 
4090   // Lower the actual args into this basic block.
4091   SmallVector<ArrayRef<Register>, 8> VRegArgs;
4092   for (const Argument &Arg: F.args()) {
4093     if (DL->getTypeStoreSize(Arg.getType()).isZero())
4094       continue; // Don't handle zero sized types.
4095     ArrayRef<Register> VRegs = getOrCreateVRegs(Arg);
4096     VRegArgs.push_back(VRegs);
4097 
4098     if (Arg.hasSwiftErrorAttr()) {
4099       assert(VRegs.size() == 1 && "Too many vregs for Swift error");
4100       SwiftError.setCurrentVReg(EntryBB, SwiftError.getFunctionArg(), VRegs[0]);
4101     }
4102   }
4103 
4104   if (!CLI->lowerFormalArguments(*EntryBuilder, F, VRegArgs, FuncInfo)) {
4105     OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
4106                                F.getSubprogram(), &F.getEntryBlock());
4107     R << "unable to lower arguments: "
4108       << ore::NV("Prototype", F.getFunctionType());
4109     reportTranslationError(*MF, *TPC, *ORE, R);
4110     return false;
4111   }
4112 
4113   // Need to visit defs before uses when translating instructions.
4114   GISelObserverWrapper WrapperObserver;
4115   if (EnableCSE && CSEInfo)
4116     WrapperObserver.addObserver(CSEInfo);
4117   {
4118     ReversePostOrderTraversal<const Function *> RPOT(&F);
4119 #ifndef NDEBUG
4120     DILocationVerifier Verifier;
4121     WrapperObserver.addObserver(&Verifier);
4122 #endif // ifndef NDEBUG
4123     RAIIMFObsDelInstaller ObsInstall(*MF, WrapperObserver);
4124     for (const BasicBlock *BB : RPOT) {
4125       MachineBasicBlock &MBB = getMBB(*BB);
4126       // Set the insertion point of all the following translations to
4127       // the end of this basic block.
4128       CurBuilder->setMBB(MBB);
4129       HasTailCall = false;
4130       for (const Instruction &Inst : *BB) {
4131         // If we translated a tail call in the last step, then we know
4132         // everything after the call is either a return, or something that is
4133         // handled by the call itself. (E.g. a lifetime marker or assume
4134         // intrinsic.) In this case, we should stop translating the block and
4135         // move on.
4136         if (HasTailCall)
4137           break;
4138 #ifndef NDEBUG
4139         Verifier.setCurrentInst(&Inst);
4140 #endif // ifndef NDEBUG
4141 
4142         // Translate any debug-info attached to the instruction.
4143         translateDbgInfo(Inst, *CurBuilder);
4144 
4145         if (translate(Inst))
4146           continue;
4147 
4148         OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
4149                                    Inst.getDebugLoc(), BB);
4150         R << "unable to translate instruction: " << ore::NV("Opcode", &Inst);
4151 
4152         if (ORE->allowExtraAnalysis("gisel-irtranslator")) {
4153           std::string InstStrStorage;
4154           raw_string_ostream InstStr(InstStrStorage);
4155           InstStr << Inst;
4156 
4157           R << ": '" << InstStrStorage << "'";
4158         }
4159 
4160         reportTranslationError(*MF, *TPC, *ORE, R);
4161         return false;
4162       }
4163 
4164       if (!finalizeBasicBlock(*BB, MBB)) {
4165         OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
4166                                    BB->getTerminator()->getDebugLoc(), BB);
4167         R << "unable to translate basic block";
4168         reportTranslationError(*MF, *TPC, *ORE, R);
4169         return false;
4170       }
4171     }
4172 #ifndef NDEBUG
4173     WrapperObserver.removeObserver(&Verifier);
4174 #endif
4175   }
4176 
4177   finishPendingPhis();
4178 
4179   SwiftError.propagateVRegs();
4180 
4181   // Merge the argument lowering and constants block with its single
4182   // successor, the LLVM-IR entry block.  We want the basic block to
4183   // be maximal.
4184   assert(EntryBB->succ_size() == 1 &&
4185          "Custom BB used for lowering should have only one successor");
4186   // Get the successor of the current entry block.
4187   MachineBasicBlock &NewEntryBB = **EntryBB->succ_begin();
4188   assert(NewEntryBB.pred_size() == 1 &&
4189          "LLVM-IR entry block has a predecessor!?");
4190   // Move all the instruction from the current entry block to the
4191   // new entry block.
4192   NewEntryBB.splice(NewEntryBB.begin(), EntryBB, EntryBB->begin(),
4193                     EntryBB->end());
4194 
4195   // Update the live-in information for the new entry block.
4196   for (const MachineBasicBlock::RegisterMaskPair &LiveIn : EntryBB->liveins())
4197     NewEntryBB.addLiveIn(LiveIn);
4198   NewEntryBB.sortUniqueLiveIns();
4199 
4200   // Get rid of the now empty basic block.
4201   EntryBB->removeSuccessor(&NewEntryBB);
4202   MF->remove(EntryBB);
4203   MF->deleteMachineBasicBlock(EntryBB);
4204 
4205   assert(&MF->front() == &NewEntryBB &&
4206          "New entry wasn't next in the list of basic block!");
4207 
4208   // Initialize stack protector information.
4209   StackProtector &SP = getAnalysis<StackProtector>();
4210   SP.copyToMachineFrameInfo(MF->getFrameInfo());
4211 
4212   return false;
4213 }
4214