xref: /llvm-project/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp (revision 5a81a559d69fb84e1e8ef623ac4b642081c14c51)
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/TargetIntrinsicInfo.h"
83 #include "llvm/Target/TargetMachine.h"
84 #include "llvm/Transforms/Utils/Local.h"
85 #include "llvm/Transforms/Utils/MemoryOpRemark.h"
86 #include <algorithm>
87 #include <cassert>
88 #include <cstdint>
89 #include <iterator>
90 #include <optional>
91 #include <string>
92 #include <utility>
93 #include <vector>
94 
95 #define DEBUG_TYPE "irtranslator"
96 
97 using namespace llvm;
98 
99 static cl::opt<bool>
100     EnableCSEInIRTranslator("enable-cse-in-irtranslator",
101                             cl::desc("Should enable CSE in irtranslator"),
102                             cl::Optional, cl::init(false));
103 char IRTranslator::ID = 0;
104 
105 INITIALIZE_PASS_BEGIN(IRTranslator, DEBUG_TYPE, "IRTranslator LLVM IR -> MI",
106                 false, false)
107 INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
108 INITIALIZE_PASS_DEPENDENCY(GISelCSEAnalysisWrapperPass)
109 INITIALIZE_PASS_DEPENDENCY(BlockFrequencyInfoWrapperPass)
110 INITIALIZE_PASS_DEPENDENCY(StackProtector)
111 INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
112 INITIALIZE_PASS_END(IRTranslator, DEBUG_TYPE, "IRTranslator LLVM IR -> MI",
113                 false, false)
114 
115 static void reportTranslationError(MachineFunction &MF,
116                                    const TargetPassConfig &TPC,
117                                    OptimizationRemarkEmitter &ORE,
118                                    OptimizationRemarkMissed &R) {
119   MF.getProperties().set(MachineFunctionProperties::Property::FailedISel);
120 
121   // Print the function name explicitly if we don't have a debug location (which
122   // makes the diagnostic less useful) or if we're going to emit a raw error.
123   if (!R.getLocation().isValid() || TPC.isGlobalISelAbortEnabled())
124     R << (" (in function: " + MF.getName() + ")").str();
125 
126   if (TPC.isGlobalISelAbortEnabled())
127     report_fatal_error(Twine(R.getMsg()));
128   else
129     ORE.emit(R);
130 }
131 
132 IRTranslator::IRTranslator(CodeGenOptLevel optlevel)
133     : MachineFunctionPass(ID), OptLevel(optlevel) {}
134 
135 #ifndef NDEBUG
136 namespace {
137 /// Verify that every instruction created has the same DILocation as the
138 /// instruction being translated.
139 class DILocationVerifier : public GISelChangeObserver {
140   const Instruction *CurrInst = nullptr;
141 
142 public:
143   DILocationVerifier() = default;
144   ~DILocationVerifier() = default;
145 
146   const Instruction *getCurrentInst() const { return CurrInst; }
147   void setCurrentInst(const Instruction *Inst) { CurrInst = Inst; }
148 
149   void erasingInstr(MachineInstr &MI) override {}
150   void changingInstr(MachineInstr &MI) override {}
151   void changedInstr(MachineInstr &MI) override {}
152 
153   void createdInstr(MachineInstr &MI) override {
154     assert(getCurrentInst() && "Inserted instruction without a current MI");
155 
156     // Only print the check message if we're actually checking it.
157 #ifndef NDEBUG
158     LLVM_DEBUG(dbgs() << "Checking DILocation from " << *CurrInst
159                       << " was copied to " << MI);
160 #endif
161     // We allow insts in the entry block to have no debug loc because
162     // they could have originated from constants, and we don't want a jumpy
163     // debug experience.
164     assert((CurrInst->getDebugLoc() == MI.getDebugLoc() ||
165             (MI.getParent()->isEntryBlock() && !MI.getDebugLoc()) ||
166             (MI.isDebugInstr())) &&
167            "Line info was not transferred to all instructions");
168   }
169 };
170 } // namespace
171 #endif // ifndef NDEBUG
172 
173 
174 void IRTranslator::getAnalysisUsage(AnalysisUsage &AU) const {
175   AU.addRequired<StackProtector>();
176   AU.addRequired<TargetPassConfig>();
177   AU.addRequired<GISelCSEAnalysisWrapperPass>();
178   AU.addRequired<AssumptionCacheTracker>();
179   if (OptLevel != CodeGenOptLevel::None) {
180     AU.addRequired<BranchProbabilityInfoWrapperPass>();
181     AU.addRequired<AAResultsWrapperPass>();
182   }
183   AU.addRequired<TargetLibraryInfoWrapperPass>();
184   AU.addPreserved<TargetLibraryInfoWrapperPass>();
185   getSelectionDAGFallbackAnalysisUsage(AU);
186   MachineFunctionPass::getAnalysisUsage(AU);
187 }
188 
189 IRTranslator::ValueToVRegInfo::VRegListT &
190 IRTranslator::allocateVRegs(const Value &Val) {
191   auto VRegsIt = VMap.findVRegs(Val);
192   if (VRegsIt != VMap.vregs_end())
193     return *VRegsIt->second;
194   auto *Regs = VMap.getVRegs(Val);
195   auto *Offsets = VMap.getOffsets(Val);
196   SmallVector<LLT, 4> SplitTys;
197   computeValueLLTs(*DL, *Val.getType(), SplitTys,
198                    Offsets->empty() ? Offsets : nullptr);
199   for (unsigned i = 0; i < SplitTys.size(); ++i)
200     Regs->push_back(0);
201   return *Regs;
202 }
203 
204 ArrayRef<Register> IRTranslator::getOrCreateVRegs(const Value &Val) {
205   auto VRegsIt = VMap.findVRegs(Val);
206   if (VRegsIt != VMap.vregs_end())
207     return *VRegsIt->second;
208 
209   if (Val.getType()->isVoidTy())
210     return *VMap.getVRegs(Val);
211 
212   // Create entry for this type.
213   auto *VRegs = VMap.getVRegs(Val);
214   auto *Offsets = VMap.getOffsets(Val);
215 
216   if (!Val.getType()->isTokenTy())
217     assert(Val.getType()->isSized() &&
218            "Don't know how to create an empty vreg");
219 
220   SmallVector<LLT, 4> SplitTys;
221   computeValueLLTs(*DL, *Val.getType(), SplitTys,
222                    Offsets->empty() ? Offsets : nullptr);
223 
224   if (!isa<Constant>(Val)) {
225     for (auto Ty : SplitTys)
226       VRegs->push_back(MRI->createGenericVirtualRegister(Ty));
227     return *VRegs;
228   }
229 
230   if (Val.getType()->isAggregateType()) {
231     // UndefValue, ConstantAggregateZero
232     auto &C = cast<Constant>(Val);
233     unsigned Idx = 0;
234     while (auto Elt = C.getAggregateElement(Idx++)) {
235       auto EltRegs = getOrCreateVRegs(*Elt);
236       llvm::copy(EltRegs, std::back_inserter(*VRegs));
237     }
238   } else {
239     assert(SplitTys.size() == 1 && "unexpectedly split LLT");
240     VRegs->push_back(MRI->createGenericVirtualRegister(SplitTys[0]));
241     bool Success = translate(cast<Constant>(Val), VRegs->front());
242     if (!Success) {
243       OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
244                                  MF->getFunction().getSubprogram(),
245                                  &MF->getFunction().getEntryBlock());
246       R << "unable to translate constant: " << ore::NV("Type", Val.getType());
247       reportTranslationError(*MF, *TPC, *ORE, R);
248       return *VRegs;
249     }
250   }
251 
252   return *VRegs;
253 }
254 
255 int IRTranslator::getOrCreateFrameIndex(const AllocaInst &AI) {
256   auto MapEntry = FrameIndices.find(&AI);
257   if (MapEntry != FrameIndices.end())
258     return MapEntry->second;
259 
260   uint64_t ElementSize = DL->getTypeAllocSize(AI.getAllocatedType());
261   uint64_t Size =
262       ElementSize * cast<ConstantInt>(AI.getArraySize())->getZExtValue();
263 
264   // Always allocate at least one byte.
265   Size = std::max<uint64_t>(Size, 1u);
266 
267   int &FI = FrameIndices[&AI];
268   FI = MF->getFrameInfo().CreateStackObject(Size, AI.getAlign(), false, &AI);
269   return FI;
270 }
271 
272 Align IRTranslator::getMemOpAlign(const Instruction &I) {
273   if (const StoreInst *SI = dyn_cast<StoreInst>(&I))
274     return SI->getAlign();
275   if (const LoadInst *LI = dyn_cast<LoadInst>(&I))
276     return LI->getAlign();
277   if (const AtomicCmpXchgInst *AI = dyn_cast<AtomicCmpXchgInst>(&I))
278     return AI->getAlign();
279   if (const AtomicRMWInst *AI = dyn_cast<AtomicRMWInst>(&I))
280     return AI->getAlign();
281 
282   OptimizationRemarkMissed R("gisel-irtranslator", "", &I);
283   R << "unable to translate memop: " << ore::NV("Opcode", &I);
284   reportTranslationError(*MF, *TPC, *ORE, R);
285   return Align(1);
286 }
287 
288 MachineBasicBlock &IRTranslator::getMBB(const BasicBlock &BB) {
289   MachineBasicBlock *MBB = FuncInfo.getMBB(&BB);
290   assert(MBB && "BasicBlock was not encountered before");
291   return *MBB;
292 }
293 
294 void IRTranslator::addMachineCFGPred(CFGEdge Edge, MachineBasicBlock *NewPred) {
295   assert(NewPred && "new predecessor must be a real MachineBasicBlock");
296   MachinePreds[Edge].push_back(NewPred);
297 }
298 
299 static bool containsBF16Type(const User &U) {
300   // BF16 cannot currently be represented by LLT, to avoid miscompiles we
301   // prevent any instructions using them. FIXME: This can be removed once LLT
302   // supports bfloat.
303   return U.getType()->getScalarType()->isBFloatTy() ||
304          any_of(U.operands(), [](Value *V) {
305            return V->getType()->getScalarType()->isBFloatTy();
306          });
307 }
308 
309 bool IRTranslator::translateBinaryOp(unsigned Opcode, const User &U,
310                                      MachineIRBuilder &MIRBuilder) {
311   if (containsBF16Type(U))
312     return false;
313 
314   // Get or create a virtual register for each value.
315   // Unless the value is a Constant => loadimm cst?
316   // or inline constant each time?
317   // Creation of a virtual register needs to have a size.
318   Register Op0 = getOrCreateVReg(*U.getOperand(0));
319   Register Op1 = getOrCreateVReg(*U.getOperand(1));
320   Register Res = getOrCreateVReg(U);
321   uint32_t Flags = 0;
322   if (isa<Instruction>(U)) {
323     const Instruction &I = cast<Instruction>(U);
324     Flags = MachineInstr::copyFlagsFromInstruction(I);
325   }
326 
327   MIRBuilder.buildInstr(Opcode, {Res}, {Op0, Op1}, Flags);
328   return true;
329 }
330 
331 bool IRTranslator::translateUnaryOp(unsigned Opcode, const User &U,
332                                     MachineIRBuilder &MIRBuilder) {
333   if (containsBF16Type(U))
334     return false;
335 
336   Register Op0 = getOrCreateVReg(*U.getOperand(0));
337   Register Res = getOrCreateVReg(U);
338   uint32_t Flags = 0;
339   if (isa<Instruction>(U)) {
340     const Instruction &I = cast<Instruction>(U);
341     Flags = MachineInstr::copyFlagsFromInstruction(I);
342   }
343   MIRBuilder.buildInstr(Opcode, {Res}, {Op0}, Flags);
344   return true;
345 }
346 
347 bool IRTranslator::translateFNeg(const User &U, MachineIRBuilder &MIRBuilder) {
348   return translateUnaryOp(TargetOpcode::G_FNEG, U, MIRBuilder);
349 }
350 
351 bool IRTranslator::translateCompare(const User &U,
352                                     MachineIRBuilder &MIRBuilder) {
353   if (containsBF16Type(U))
354     return false;
355 
356   auto *CI = cast<CmpInst>(&U);
357   Register Op0 = getOrCreateVReg(*U.getOperand(0));
358   Register Op1 = getOrCreateVReg(*U.getOperand(1));
359   Register Res = getOrCreateVReg(U);
360   CmpInst::Predicate Pred = CI->getPredicate();
361   uint32_t Flags = MachineInstr::copyFlagsFromInstruction(*CI);
362   if (CmpInst::isIntPredicate(Pred))
363     MIRBuilder.buildICmp(Pred, Res, Op0, Op1, Flags);
364   else if (Pred == CmpInst::FCMP_FALSE)
365     MIRBuilder.buildCopy(
366         Res, getOrCreateVReg(*Constant::getNullValue(U.getType())));
367   else if (Pred == CmpInst::FCMP_TRUE)
368     MIRBuilder.buildCopy(
369         Res, getOrCreateVReg(*Constant::getAllOnesValue(U.getType())));
370   else
371     MIRBuilder.buildFCmp(Pred, Res, Op0, Op1, Flags);
372 
373   return true;
374 }
375 
376 bool IRTranslator::translateRet(const User &U, MachineIRBuilder &MIRBuilder) {
377   const ReturnInst &RI = cast<ReturnInst>(U);
378   const Value *Ret = RI.getReturnValue();
379   if (Ret && DL->getTypeStoreSize(Ret->getType()).isZero())
380     Ret = nullptr;
381 
382   ArrayRef<Register> VRegs;
383   if (Ret)
384     VRegs = getOrCreateVRegs(*Ret);
385 
386   Register SwiftErrorVReg = 0;
387   if (CLI->supportSwiftError() && SwiftError.getFunctionArg()) {
388     SwiftErrorVReg = SwiftError.getOrCreateVRegUseAt(
389         &RI, &MIRBuilder.getMBB(), SwiftError.getFunctionArg());
390   }
391 
392   // The target may mess up with the insertion point, but
393   // this is not important as a return is the last instruction
394   // of the block anyway.
395   return CLI->lowerReturn(MIRBuilder, Ret, VRegs, FuncInfo, SwiftErrorVReg);
396 }
397 
398 void IRTranslator::emitBranchForMergedCondition(
399     const Value *Cond, MachineBasicBlock *TBB, MachineBasicBlock *FBB,
400     MachineBasicBlock *CurBB, MachineBasicBlock *SwitchBB,
401     BranchProbability TProb, BranchProbability FProb, bool InvertCond) {
402   // If the leaf of the tree is a comparison, merge the condition into
403   // the caseblock.
404   if (const CmpInst *BOp = dyn_cast<CmpInst>(Cond)) {
405     CmpInst::Predicate Condition;
406     if (const ICmpInst *IC = dyn_cast<ICmpInst>(Cond)) {
407       Condition = InvertCond ? IC->getInversePredicate() : IC->getPredicate();
408     } else {
409       const FCmpInst *FC = cast<FCmpInst>(Cond);
410       Condition = InvertCond ? FC->getInversePredicate() : FC->getPredicate();
411     }
412 
413     SwitchCG::CaseBlock CB(Condition, false, BOp->getOperand(0),
414                            BOp->getOperand(1), nullptr, TBB, FBB, CurBB,
415                            CurBuilder->getDebugLoc(), TProb, FProb);
416     SL->SwitchCases.push_back(CB);
417     return;
418   }
419 
420   // Create a CaseBlock record representing this branch.
421   CmpInst::Predicate Pred = InvertCond ? CmpInst::ICMP_NE : CmpInst::ICMP_EQ;
422   SwitchCG::CaseBlock CB(
423       Pred, false, Cond, ConstantInt::getTrue(MF->getFunction().getContext()),
424       nullptr, TBB, FBB, CurBB, CurBuilder->getDebugLoc(), TProb, FProb);
425   SL->SwitchCases.push_back(CB);
426 }
427 
428 static bool isValInBlock(const Value *V, const BasicBlock *BB) {
429   if (const Instruction *I = dyn_cast<Instruction>(V))
430     return I->getParent() == BB;
431   return true;
432 }
433 
434 void IRTranslator::findMergedConditions(
435     const Value *Cond, MachineBasicBlock *TBB, MachineBasicBlock *FBB,
436     MachineBasicBlock *CurBB, MachineBasicBlock *SwitchBB,
437     Instruction::BinaryOps Opc, BranchProbability TProb,
438     BranchProbability FProb, bool InvertCond) {
439   using namespace PatternMatch;
440   assert((Opc == Instruction::And || Opc == Instruction::Or) &&
441          "Expected Opc to be AND/OR");
442   // Skip over not part of the tree and remember to invert op and operands at
443   // next level.
444   Value *NotCond;
445   if (match(Cond, m_OneUse(m_Not(m_Value(NotCond)))) &&
446       isValInBlock(NotCond, CurBB->getBasicBlock())) {
447     findMergedConditions(NotCond, TBB, FBB, CurBB, SwitchBB, Opc, TProb, FProb,
448                          !InvertCond);
449     return;
450   }
451 
452   const Instruction *BOp = dyn_cast<Instruction>(Cond);
453   const Value *BOpOp0, *BOpOp1;
454   // Compute the effective opcode for Cond, taking into account whether it needs
455   // to be inverted, e.g.
456   //   and (not (or A, B)), C
457   // gets lowered as
458   //   and (and (not A, not B), C)
459   Instruction::BinaryOps BOpc = (Instruction::BinaryOps)0;
460   if (BOp) {
461     BOpc = match(BOp, m_LogicalAnd(m_Value(BOpOp0), m_Value(BOpOp1)))
462                ? Instruction::And
463                : (match(BOp, m_LogicalOr(m_Value(BOpOp0), m_Value(BOpOp1)))
464                       ? Instruction::Or
465                       : (Instruction::BinaryOps)0);
466     if (InvertCond) {
467       if (BOpc == Instruction::And)
468         BOpc = Instruction::Or;
469       else if (BOpc == Instruction::Or)
470         BOpc = Instruction::And;
471     }
472   }
473 
474   // If this node is not part of the or/and tree, emit it as a branch.
475   // Note that all nodes in the tree should have same opcode.
476   bool BOpIsInOrAndTree = BOpc && BOpc == Opc && BOp->hasOneUse();
477   if (!BOpIsInOrAndTree || BOp->getParent() != CurBB->getBasicBlock() ||
478       !isValInBlock(BOpOp0, CurBB->getBasicBlock()) ||
479       !isValInBlock(BOpOp1, CurBB->getBasicBlock())) {
480     emitBranchForMergedCondition(Cond, TBB, FBB, CurBB, SwitchBB, TProb, FProb,
481                                  InvertCond);
482     return;
483   }
484 
485   //  Create TmpBB after CurBB.
486   MachineFunction::iterator BBI(CurBB);
487   MachineBasicBlock *TmpBB =
488       MF->CreateMachineBasicBlock(CurBB->getBasicBlock());
489   CurBB->getParent()->insert(++BBI, TmpBB);
490 
491   if (Opc == Instruction::Or) {
492     // Codegen X | Y as:
493     // BB1:
494     //   jmp_if_X TBB
495     //   jmp TmpBB
496     // TmpBB:
497     //   jmp_if_Y TBB
498     //   jmp FBB
499     //
500 
501     // We have flexibility in setting Prob for BB1 and Prob for TmpBB.
502     // The requirement is that
503     //   TrueProb for BB1 + (FalseProb for BB1 * TrueProb for TmpBB)
504     //     = TrueProb for original BB.
505     // Assuming the original probabilities are A and B, one choice is to set
506     // BB1's probabilities to A/2 and A/2+B, and set TmpBB's probabilities to
507     // A/(1+B) and 2B/(1+B). This choice assumes that
508     //   TrueProb for BB1 == FalseProb for BB1 * TrueProb for TmpBB.
509     // Another choice is to assume TrueProb for BB1 equals to TrueProb for
510     // TmpBB, but the math is more complicated.
511 
512     auto NewTrueProb = TProb / 2;
513     auto NewFalseProb = TProb / 2 + FProb;
514     // Emit the LHS condition.
515     findMergedConditions(BOpOp0, TBB, TmpBB, CurBB, SwitchBB, Opc, NewTrueProb,
516                          NewFalseProb, InvertCond);
517 
518     // Normalize A/2 and B to get A/(1+B) and 2B/(1+B).
519     SmallVector<BranchProbability, 2> Probs{TProb / 2, FProb};
520     BranchProbability::normalizeProbabilities(Probs.begin(), Probs.end());
521     // Emit the RHS condition into TmpBB.
522     findMergedConditions(BOpOp1, TBB, FBB, TmpBB, SwitchBB, Opc, Probs[0],
523                          Probs[1], InvertCond);
524   } else {
525     assert(Opc == Instruction::And && "Unknown merge op!");
526     // Codegen X & Y as:
527     // BB1:
528     //   jmp_if_X TmpBB
529     //   jmp FBB
530     // TmpBB:
531     //   jmp_if_Y TBB
532     //   jmp FBB
533     //
534     //  This requires creation of TmpBB after CurBB.
535 
536     // We have flexibility in setting Prob for BB1 and Prob for TmpBB.
537     // The requirement is that
538     //   FalseProb for BB1 + (TrueProb for BB1 * FalseProb for TmpBB)
539     //     = FalseProb for original BB.
540     // Assuming the original probabilities are A and B, one choice is to set
541     // BB1's probabilities to A+B/2 and B/2, and set TmpBB's probabilities to
542     // 2A/(1+A) and B/(1+A). This choice assumes that FalseProb for BB1 ==
543     // TrueProb for BB1 * FalseProb for TmpBB.
544 
545     auto NewTrueProb = TProb + FProb / 2;
546     auto NewFalseProb = FProb / 2;
547     // Emit the LHS condition.
548     findMergedConditions(BOpOp0, TmpBB, FBB, CurBB, SwitchBB, Opc, NewTrueProb,
549                          NewFalseProb, InvertCond);
550 
551     // Normalize A and B/2 to get 2A/(1+A) and B/(1+A).
552     SmallVector<BranchProbability, 2> Probs{TProb, FProb / 2};
553     BranchProbability::normalizeProbabilities(Probs.begin(), Probs.end());
554     // Emit the RHS condition into TmpBB.
555     findMergedConditions(BOpOp1, TBB, FBB, TmpBB, SwitchBB, Opc, Probs[0],
556                          Probs[1], InvertCond);
557   }
558 }
559 
560 bool IRTranslator::shouldEmitAsBranches(
561     const std::vector<SwitchCG::CaseBlock> &Cases) {
562   // For multiple cases, it's better to emit as branches.
563   if (Cases.size() != 2)
564     return true;
565 
566   // If this is two comparisons of the same values or'd or and'd together, they
567   // will get folded into a single comparison, so don't emit two blocks.
568   if ((Cases[0].CmpLHS == Cases[1].CmpLHS &&
569        Cases[0].CmpRHS == Cases[1].CmpRHS) ||
570       (Cases[0].CmpRHS == Cases[1].CmpLHS &&
571        Cases[0].CmpLHS == Cases[1].CmpRHS)) {
572     return false;
573   }
574 
575   // Handle: (X != null) | (Y != null) --> (X|Y) != 0
576   // Handle: (X == null) & (Y == null) --> (X|Y) == 0
577   if (Cases[0].CmpRHS == Cases[1].CmpRHS &&
578       Cases[0].PredInfo.Pred == Cases[1].PredInfo.Pred &&
579       isa<Constant>(Cases[0].CmpRHS) &&
580       cast<Constant>(Cases[0].CmpRHS)->isNullValue()) {
581     if (Cases[0].PredInfo.Pred == CmpInst::ICMP_EQ &&
582         Cases[0].TrueBB == Cases[1].ThisBB)
583       return false;
584     if (Cases[0].PredInfo.Pred == CmpInst::ICMP_NE &&
585         Cases[0].FalseBB == Cases[1].ThisBB)
586       return false;
587   }
588 
589   return true;
590 }
591 
592 bool IRTranslator::translateBr(const User &U, MachineIRBuilder &MIRBuilder) {
593   const BranchInst &BrInst = cast<BranchInst>(U);
594   auto &CurMBB = MIRBuilder.getMBB();
595   auto *Succ0MBB = &getMBB(*BrInst.getSuccessor(0));
596 
597   if (BrInst.isUnconditional()) {
598     // If the unconditional target is the layout successor, fallthrough.
599     if (OptLevel == CodeGenOptLevel::None ||
600         !CurMBB.isLayoutSuccessor(Succ0MBB))
601       MIRBuilder.buildBr(*Succ0MBB);
602 
603     // Link successors.
604     for (const BasicBlock *Succ : successors(&BrInst))
605       CurMBB.addSuccessor(&getMBB(*Succ));
606     return true;
607   }
608 
609   // If this condition is one of the special cases we handle, do special stuff
610   // now.
611   const Value *CondVal = BrInst.getCondition();
612   MachineBasicBlock *Succ1MBB = &getMBB(*BrInst.getSuccessor(1));
613 
614   // If this is a series of conditions that are or'd or and'd together, emit
615   // this as a sequence of branches instead of setcc's with and/or operations.
616   // As long as jumps are not expensive (exceptions for multi-use logic ops,
617   // unpredictable branches, and vector extracts because those jumps are likely
618   // expensive for any target), this should improve performance.
619   // For example, instead of something like:
620   //     cmp A, B
621   //     C = seteq
622   //     cmp D, E
623   //     F = setle
624   //     or C, F
625   //     jnz foo
626   // Emit:
627   //     cmp A, B
628   //     je foo
629   //     cmp D, E
630   //     jle foo
631   using namespace PatternMatch;
632   const Instruction *CondI = dyn_cast<Instruction>(CondVal);
633   if (!TLI->isJumpExpensive() && CondI && CondI->hasOneUse() &&
634       !BrInst.hasMetadata(LLVMContext::MD_unpredictable)) {
635     Instruction::BinaryOps Opcode = (Instruction::BinaryOps)0;
636     Value *Vec;
637     const Value *BOp0, *BOp1;
638     if (match(CondI, m_LogicalAnd(m_Value(BOp0), m_Value(BOp1))))
639       Opcode = Instruction::And;
640     else if (match(CondI, m_LogicalOr(m_Value(BOp0), m_Value(BOp1))))
641       Opcode = Instruction::Or;
642 
643     if (Opcode && !(match(BOp0, m_ExtractElt(m_Value(Vec), m_Value())) &&
644                     match(BOp1, m_ExtractElt(m_Specific(Vec), m_Value())))) {
645       findMergedConditions(CondI, Succ0MBB, Succ1MBB, &CurMBB, &CurMBB, Opcode,
646                            getEdgeProbability(&CurMBB, Succ0MBB),
647                            getEdgeProbability(&CurMBB, Succ1MBB),
648                            /*InvertCond=*/false);
649       assert(SL->SwitchCases[0].ThisBB == &CurMBB && "Unexpected lowering!");
650 
651       // Allow some cases to be rejected.
652       if (shouldEmitAsBranches(SL->SwitchCases)) {
653         // Emit the branch for this block.
654         emitSwitchCase(SL->SwitchCases[0], &CurMBB, *CurBuilder);
655         SL->SwitchCases.erase(SL->SwitchCases.begin());
656         return true;
657       }
658 
659       // Okay, we decided not to do this, remove any inserted MBB's and clear
660       // SwitchCases.
661       for (unsigned I = 1, E = SL->SwitchCases.size(); I != E; ++I)
662         MF->erase(SL->SwitchCases[I].ThisBB);
663 
664       SL->SwitchCases.clear();
665     }
666   }
667 
668   // Create a CaseBlock record representing this branch.
669   SwitchCG::CaseBlock CB(CmpInst::ICMP_EQ, false, CondVal,
670                          ConstantInt::getTrue(MF->getFunction().getContext()),
671                          nullptr, Succ0MBB, Succ1MBB, &CurMBB,
672                          CurBuilder->getDebugLoc());
673 
674   // Use emitSwitchCase to actually insert the fast branch sequence for this
675   // cond branch.
676   emitSwitchCase(CB, &CurMBB, *CurBuilder);
677   return true;
678 }
679 
680 void IRTranslator::addSuccessorWithProb(MachineBasicBlock *Src,
681                                         MachineBasicBlock *Dst,
682                                         BranchProbability Prob) {
683   if (!FuncInfo.BPI) {
684     Src->addSuccessorWithoutProb(Dst);
685     return;
686   }
687   if (Prob.isUnknown())
688     Prob = getEdgeProbability(Src, Dst);
689   Src->addSuccessor(Dst, Prob);
690 }
691 
692 BranchProbability
693 IRTranslator::getEdgeProbability(const MachineBasicBlock *Src,
694                                  const MachineBasicBlock *Dst) const {
695   const BasicBlock *SrcBB = Src->getBasicBlock();
696   const BasicBlock *DstBB = Dst->getBasicBlock();
697   if (!FuncInfo.BPI) {
698     // If BPI is not available, set the default probability as 1 / N, where N is
699     // the number of successors.
700     auto SuccSize = std::max<uint32_t>(succ_size(SrcBB), 1);
701     return BranchProbability(1, SuccSize);
702   }
703   return FuncInfo.BPI->getEdgeProbability(SrcBB, DstBB);
704 }
705 
706 bool IRTranslator::translateSwitch(const User &U, MachineIRBuilder &MIB) {
707   using namespace SwitchCG;
708   // Extract cases from the switch.
709   const SwitchInst &SI = cast<SwitchInst>(U);
710   BranchProbabilityInfo *BPI = FuncInfo.BPI;
711   CaseClusterVector Clusters;
712   Clusters.reserve(SI.getNumCases());
713   for (const auto &I : SI.cases()) {
714     MachineBasicBlock *Succ = &getMBB(*I.getCaseSuccessor());
715     assert(Succ && "Could not find successor mbb in mapping");
716     const ConstantInt *CaseVal = I.getCaseValue();
717     BranchProbability Prob =
718         BPI ? BPI->getEdgeProbability(SI.getParent(), I.getSuccessorIndex())
719             : BranchProbability(1, SI.getNumCases() + 1);
720     Clusters.push_back(CaseCluster::range(CaseVal, CaseVal, Succ, Prob));
721   }
722 
723   MachineBasicBlock *DefaultMBB = &getMBB(*SI.getDefaultDest());
724 
725   // Cluster adjacent cases with the same destination. We do this at all
726   // optimization levels because it's cheap to do and will make codegen faster
727   // if there are many clusters.
728   sortAndRangeify(Clusters);
729 
730   MachineBasicBlock *SwitchMBB = &getMBB(*SI.getParent());
731 
732   // If there is only the default destination, jump there directly.
733   if (Clusters.empty()) {
734     SwitchMBB->addSuccessor(DefaultMBB);
735     if (DefaultMBB != SwitchMBB->getNextNode())
736       MIB.buildBr(*DefaultMBB);
737     return true;
738   }
739 
740   SL->findJumpTables(Clusters, &SI, std::nullopt, DefaultMBB, nullptr, nullptr);
741   SL->findBitTestClusters(Clusters, &SI);
742 
743   LLVM_DEBUG({
744     dbgs() << "Case clusters: ";
745     for (const CaseCluster &C : Clusters) {
746       if (C.Kind == CC_JumpTable)
747         dbgs() << "JT:";
748       if (C.Kind == CC_BitTests)
749         dbgs() << "BT:";
750 
751       C.Low->getValue().print(dbgs(), true);
752       if (C.Low != C.High) {
753         dbgs() << '-';
754         C.High->getValue().print(dbgs(), true);
755       }
756       dbgs() << ' ';
757     }
758     dbgs() << '\n';
759   });
760 
761   assert(!Clusters.empty());
762   SwitchWorkList WorkList;
763   CaseClusterIt First = Clusters.begin();
764   CaseClusterIt Last = Clusters.end() - 1;
765   auto DefaultProb = getEdgeProbability(SwitchMBB, DefaultMBB);
766   WorkList.push_back({SwitchMBB, First, Last, nullptr, nullptr, DefaultProb});
767 
768   while (!WorkList.empty()) {
769     SwitchWorkListItem W = WorkList.pop_back_val();
770 
771     unsigned NumClusters = W.LastCluster - W.FirstCluster + 1;
772     // For optimized builds, lower large range as a balanced binary tree.
773     if (NumClusters > 3 &&
774         MF->getTarget().getOptLevel() != CodeGenOptLevel::None &&
775         !DefaultMBB->getParent()->getFunction().hasMinSize()) {
776       splitWorkItem(WorkList, W, SI.getCondition(), SwitchMBB, MIB);
777       continue;
778     }
779 
780     if (!lowerSwitchWorkItem(W, SI.getCondition(), SwitchMBB, DefaultMBB, MIB))
781       return false;
782   }
783   return true;
784 }
785 
786 void IRTranslator::splitWorkItem(SwitchCG::SwitchWorkList &WorkList,
787                                  const SwitchCG::SwitchWorkListItem &W,
788                                  Value *Cond, MachineBasicBlock *SwitchMBB,
789                                  MachineIRBuilder &MIB) {
790   using namespace SwitchCG;
791   assert(W.FirstCluster->Low->getValue().slt(W.LastCluster->Low->getValue()) &&
792          "Clusters not sorted?");
793   assert(W.LastCluster - W.FirstCluster + 1 >= 2 && "Too small to split!");
794 
795   auto [LastLeft, FirstRight, LeftProb, RightProb] =
796       SL->computeSplitWorkItemInfo(W);
797 
798   // Use the first element on the right as pivot since we will make less-than
799   // comparisons against it.
800   CaseClusterIt PivotCluster = FirstRight;
801   assert(PivotCluster > W.FirstCluster);
802   assert(PivotCluster <= W.LastCluster);
803 
804   CaseClusterIt FirstLeft = W.FirstCluster;
805   CaseClusterIt LastRight = W.LastCluster;
806 
807   const ConstantInt *Pivot = PivotCluster->Low;
808 
809   // New blocks will be inserted immediately after the current one.
810   MachineFunction::iterator BBI(W.MBB);
811   ++BBI;
812 
813   // We will branch to the LHS if Value < Pivot. If LHS is a single cluster,
814   // we can branch to its destination directly if it's squeezed exactly in
815   // between the known lower bound and Pivot - 1.
816   MachineBasicBlock *LeftMBB;
817   if (FirstLeft == LastLeft && FirstLeft->Kind == CC_Range &&
818       FirstLeft->Low == W.GE &&
819       (FirstLeft->High->getValue() + 1LL) == Pivot->getValue()) {
820     LeftMBB = FirstLeft->MBB;
821   } else {
822     LeftMBB = FuncInfo.MF->CreateMachineBasicBlock(W.MBB->getBasicBlock());
823     FuncInfo.MF->insert(BBI, LeftMBB);
824     WorkList.push_back(
825         {LeftMBB, FirstLeft, LastLeft, W.GE, Pivot, W.DefaultProb / 2});
826   }
827 
828   // Similarly, we will branch to the RHS if Value >= Pivot. If RHS is a
829   // single cluster, RHS.Low == Pivot, and we can branch to its destination
830   // directly if RHS.High equals the current upper bound.
831   MachineBasicBlock *RightMBB;
832   if (FirstRight == LastRight && FirstRight->Kind == CC_Range && W.LT &&
833       (FirstRight->High->getValue() + 1ULL) == W.LT->getValue()) {
834     RightMBB = FirstRight->MBB;
835   } else {
836     RightMBB = FuncInfo.MF->CreateMachineBasicBlock(W.MBB->getBasicBlock());
837     FuncInfo.MF->insert(BBI, RightMBB);
838     WorkList.push_back(
839         {RightMBB, FirstRight, LastRight, Pivot, W.LT, W.DefaultProb / 2});
840   }
841 
842   // Create the CaseBlock record that will be used to lower the branch.
843   CaseBlock CB(ICmpInst::Predicate::ICMP_SLT, false, Cond, Pivot, nullptr,
844                LeftMBB, RightMBB, W.MBB, MIB.getDebugLoc(), LeftProb,
845                RightProb);
846 
847   if (W.MBB == SwitchMBB)
848     emitSwitchCase(CB, SwitchMBB, MIB);
849   else
850     SL->SwitchCases.push_back(CB);
851 }
852 
853 void IRTranslator::emitJumpTable(SwitchCG::JumpTable &JT,
854                                  MachineBasicBlock *MBB) {
855   // Emit the code for the jump table
856   assert(JT.Reg && "Should lower JT Header first!");
857   MachineIRBuilder MIB(*MBB->getParent());
858   MIB.setMBB(*MBB);
859   MIB.setDebugLoc(CurBuilder->getDebugLoc());
860 
861   Type *PtrIRTy = PointerType::getUnqual(MF->getFunction().getContext());
862   const LLT PtrTy = getLLTForType(*PtrIRTy, *DL);
863 
864   auto Table = MIB.buildJumpTable(PtrTy, JT.JTI);
865   MIB.buildBrJT(Table.getReg(0), JT.JTI, JT.Reg);
866 }
867 
868 bool IRTranslator::emitJumpTableHeader(SwitchCG::JumpTable &JT,
869                                        SwitchCG::JumpTableHeader &JTH,
870                                        MachineBasicBlock *HeaderBB) {
871   MachineIRBuilder MIB(*HeaderBB->getParent());
872   MIB.setMBB(*HeaderBB);
873   MIB.setDebugLoc(CurBuilder->getDebugLoc());
874 
875   const Value &SValue = *JTH.SValue;
876   // Subtract the lowest switch case value from the value being switched on.
877   const LLT SwitchTy = getLLTForType(*SValue.getType(), *DL);
878   Register SwitchOpReg = getOrCreateVReg(SValue);
879   auto FirstCst = MIB.buildConstant(SwitchTy, JTH.First);
880   auto Sub = MIB.buildSub({SwitchTy}, SwitchOpReg, FirstCst);
881 
882   // This value may be smaller or larger than the target's pointer type, and
883   // therefore require extension or truncating.
884   auto *PtrIRTy = PointerType::getUnqual(SValue.getContext());
885   const LLT PtrScalarTy = LLT::scalar(DL->getTypeSizeInBits(PtrIRTy));
886   Sub = MIB.buildZExtOrTrunc(PtrScalarTy, Sub);
887 
888   JT.Reg = Sub.getReg(0);
889 
890   if (JTH.FallthroughUnreachable) {
891     if (JT.MBB != HeaderBB->getNextNode())
892       MIB.buildBr(*JT.MBB);
893     return true;
894   }
895 
896   // Emit the range check for the jump table, and branch to the default block
897   // for the switch statement if the value being switched on exceeds the
898   // largest case in the switch.
899   auto Cst = getOrCreateVReg(
900       *ConstantInt::get(SValue.getType(), JTH.Last - JTH.First));
901   Cst = MIB.buildZExtOrTrunc(PtrScalarTy, Cst).getReg(0);
902   auto Cmp = MIB.buildICmp(CmpInst::ICMP_UGT, LLT::scalar(1), Sub, Cst);
903 
904   auto BrCond = MIB.buildBrCond(Cmp.getReg(0), *JT.Default);
905 
906   // Avoid emitting unnecessary branches to the next block.
907   if (JT.MBB != HeaderBB->getNextNode())
908     BrCond = MIB.buildBr(*JT.MBB);
909   return true;
910 }
911 
912 void IRTranslator::emitSwitchCase(SwitchCG::CaseBlock &CB,
913                                   MachineBasicBlock *SwitchBB,
914                                   MachineIRBuilder &MIB) {
915   Register CondLHS = getOrCreateVReg(*CB.CmpLHS);
916   Register Cond;
917   DebugLoc OldDbgLoc = MIB.getDebugLoc();
918   MIB.setDebugLoc(CB.DbgLoc);
919   MIB.setMBB(*CB.ThisBB);
920 
921   if (CB.PredInfo.NoCmp) {
922     // Branch or fall through to TrueBB.
923     addSuccessorWithProb(CB.ThisBB, CB.TrueBB, CB.TrueProb);
924     addMachineCFGPred({SwitchBB->getBasicBlock(), CB.TrueBB->getBasicBlock()},
925                       CB.ThisBB);
926     CB.ThisBB->normalizeSuccProbs();
927     if (CB.TrueBB != CB.ThisBB->getNextNode())
928       MIB.buildBr(*CB.TrueBB);
929     MIB.setDebugLoc(OldDbgLoc);
930     return;
931   }
932 
933   const LLT i1Ty = LLT::scalar(1);
934   // Build the compare.
935   if (!CB.CmpMHS) {
936     const auto *CI = dyn_cast<ConstantInt>(CB.CmpRHS);
937     // For conditional branch lowering, we might try to do something silly like
938     // emit an G_ICMP to compare an existing G_ICMP i1 result with true. If so,
939     // just re-use the existing condition vreg.
940     if (MRI->getType(CondLHS).getSizeInBits() == 1 && CI && CI->isOne() &&
941         CB.PredInfo.Pred == CmpInst::ICMP_EQ) {
942       Cond = CondLHS;
943     } else {
944       Register CondRHS = getOrCreateVReg(*CB.CmpRHS);
945       if (CmpInst::isFPPredicate(CB.PredInfo.Pred))
946         Cond =
947             MIB.buildFCmp(CB.PredInfo.Pred, i1Ty, CondLHS, CondRHS).getReg(0);
948       else
949         Cond =
950             MIB.buildICmp(CB.PredInfo.Pred, i1Ty, CondLHS, CondRHS).getReg(0);
951     }
952   } else {
953     assert(CB.PredInfo.Pred == CmpInst::ICMP_SLE &&
954            "Can only handle SLE ranges");
955 
956     const APInt& Low = cast<ConstantInt>(CB.CmpLHS)->getValue();
957     const APInt& High = cast<ConstantInt>(CB.CmpRHS)->getValue();
958 
959     Register CmpOpReg = getOrCreateVReg(*CB.CmpMHS);
960     if (cast<ConstantInt>(CB.CmpLHS)->isMinValue(true)) {
961       Register CondRHS = getOrCreateVReg(*CB.CmpRHS);
962       Cond =
963           MIB.buildICmp(CmpInst::ICMP_SLE, i1Ty, CmpOpReg, CondRHS).getReg(0);
964     } else {
965       const LLT CmpTy = MRI->getType(CmpOpReg);
966       auto Sub = MIB.buildSub({CmpTy}, CmpOpReg, CondLHS);
967       auto Diff = MIB.buildConstant(CmpTy, High - Low);
968       Cond = MIB.buildICmp(CmpInst::ICMP_ULE, i1Ty, Sub, Diff).getReg(0);
969     }
970   }
971 
972   // Update successor info
973   addSuccessorWithProb(CB.ThisBB, CB.TrueBB, CB.TrueProb);
974 
975   addMachineCFGPred({SwitchBB->getBasicBlock(), CB.TrueBB->getBasicBlock()},
976                     CB.ThisBB);
977 
978   // TrueBB and FalseBB are always different unless the incoming IR is
979   // degenerate. This only happens when running llc on weird IR.
980   if (CB.TrueBB != CB.FalseBB)
981     addSuccessorWithProb(CB.ThisBB, CB.FalseBB, CB.FalseProb);
982   CB.ThisBB->normalizeSuccProbs();
983 
984   addMachineCFGPred({SwitchBB->getBasicBlock(), CB.FalseBB->getBasicBlock()},
985                     CB.ThisBB);
986 
987   MIB.buildBrCond(Cond, *CB.TrueBB);
988   MIB.buildBr(*CB.FalseBB);
989   MIB.setDebugLoc(OldDbgLoc);
990 }
991 
992 bool IRTranslator::lowerJumpTableWorkItem(SwitchCG::SwitchWorkListItem W,
993                                           MachineBasicBlock *SwitchMBB,
994                                           MachineBasicBlock *CurMBB,
995                                           MachineBasicBlock *DefaultMBB,
996                                           MachineIRBuilder &MIB,
997                                           MachineFunction::iterator BBI,
998                                           BranchProbability UnhandledProbs,
999                                           SwitchCG::CaseClusterIt I,
1000                                           MachineBasicBlock *Fallthrough,
1001                                           bool FallthroughUnreachable) {
1002   using namespace SwitchCG;
1003   MachineFunction *CurMF = SwitchMBB->getParent();
1004   // FIXME: Optimize away range check based on pivot comparisons.
1005   JumpTableHeader *JTH = &SL->JTCases[I->JTCasesIndex].first;
1006   SwitchCG::JumpTable *JT = &SL->JTCases[I->JTCasesIndex].second;
1007   BranchProbability DefaultProb = W.DefaultProb;
1008 
1009   // The jump block hasn't been inserted yet; insert it here.
1010   MachineBasicBlock *JumpMBB = JT->MBB;
1011   CurMF->insert(BBI, JumpMBB);
1012 
1013   // Since the jump table block is separate from the switch block, we need
1014   // to keep track of it as a machine predecessor to the default block,
1015   // otherwise we lose the phi edges.
1016   addMachineCFGPred({SwitchMBB->getBasicBlock(), DefaultMBB->getBasicBlock()},
1017                     CurMBB);
1018   addMachineCFGPred({SwitchMBB->getBasicBlock(), DefaultMBB->getBasicBlock()},
1019                     JumpMBB);
1020 
1021   auto JumpProb = I->Prob;
1022   auto FallthroughProb = UnhandledProbs;
1023 
1024   // If the default statement is a target of the jump table, we evenly
1025   // distribute the default probability to successors of CurMBB. Also
1026   // update the probability on the edge from JumpMBB to Fallthrough.
1027   for (MachineBasicBlock::succ_iterator SI = JumpMBB->succ_begin(),
1028                                         SE = JumpMBB->succ_end();
1029        SI != SE; ++SI) {
1030     if (*SI == DefaultMBB) {
1031       JumpProb += DefaultProb / 2;
1032       FallthroughProb -= DefaultProb / 2;
1033       JumpMBB->setSuccProbability(SI, DefaultProb / 2);
1034       JumpMBB->normalizeSuccProbs();
1035     } else {
1036       // Also record edges from the jump table block to it's successors.
1037       addMachineCFGPred({SwitchMBB->getBasicBlock(), (*SI)->getBasicBlock()},
1038                         JumpMBB);
1039     }
1040   }
1041 
1042   if (FallthroughUnreachable)
1043     JTH->FallthroughUnreachable = true;
1044 
1045   if (!JTH->FallthroughUnreachable)
1046     addSuccessorWithProb(CurMBB, Fallthrough, FallthroughProb);
1047   addSuccessorWithProb(CurMBB, JumpMBB, JumpProb);
1048   CurMBB->normalizeSuccProbs();
1049 
1050   // The jump table header will be inserted in our current block, do the
1051   // range check, and fall through to our fallthrough block.
1052   JTH->HeaderBB = CurMBB;
1053   JT->Default = Fallthrough; // FIXME: Move Default to JumpTableHeader.
1054 
1055   // If we're in the right place, emit the jump table header right now.
1056   if (CurMBB == SwitchMBB) {
1057     if (!emitJumpTableHeader(*JT, *JTH, CurMBB))
1058       return false;
1059     JTH->Emitted = true;
1060   }
1061   return true;
1062 }
1063 bool IRTranslator::lowerSwitchRangeWorkItem(SwitchCG::CaseClusterIt I,
1064                                             Value *Cond,
1065                                             MachineBasicBlock *Fallthrough,
1066                                             bool FallthroughUnreachable,
1067                                             BranchProbability UnhandledProbs,
1068                                             MachineBasicBlock *CurMBB,
1069                                             MachineIRBuilder &MIB,
1070                                             MachineBasicBlock *SwitchMBB) {
1071   using namespace SwitchCG;
1072   const Value *RHS, *LHS, *MHS;
1073   CmpInst::Predicate Pred;
1074   if (I->Low == I->High) {
1075     // Check Cond == I->Low.
1076     Pred = CmpInst::ICMP_EQ;
1077     LHS = Cond;
1078     RHS = I->Low;
1079     MHS = nullptr;
1080   } else {
1081     // Check I->Low <= Cond <= I->High.
1082     Pred = CmpInst::ICMP_SLE;
1083     LHS = I->Low;
1084     MHS = Cond;
1085     RHS = I->High;
1086   }
1087 
1088   // If Fallthrough is unreachable, fold away the comparison.
1089   // The false probability is the sum of all unhandled cases.
1090   CaseBlock CB(Pred, FallthroughUnreachable, LHS, RHS, MHS, I->MBB, Fallthrough,
1091                CurMBB, MIB.getDebugLoc(), I->Prob, UnhandledProbs);
1092 
1093   emitSwitchCase(CB, SwitchMBB, MIB);
1094   return true;
1095 }
1096 
1097 void IRTranslator::emitBitTestHeader(SwitchCG::BitTestBlock &B,
1098                                      MachineBasicBlock *SwitchBB) {
1099   MachineIRBuilder &MIB = *CurBuilder;
1100   MIB.setMBB(*SwitchBB);
1101 
1102   // Subtract the minimum value.
1103   Register SwitchOpReg = getOrCreateVReg(*B.SValue);
1104 
1105   LLT SwitchOpTy = MRI->getType(SwitchOpReg);
1106   Register MinValReg = MIB.buildConstant(SwitchOpTy, B.First).getReg(0);
1107   auto RangeSub = MIB.buildSub(SwitchOpTy, SwitchOpReg, MinValReg);
1108 
1109   Type *PtrIRTy = PointerType::getUnqual(MF->getFunction().getContext());
1110   const LLT PtrTy = getLLTForType(*PtrIRTy, *DL);
1111 
1112   LLT MaskTy = SwitchOpTy;
1113   if (MaskTy.getSizeInBits() > PtrTy.getSizeInBits() ||
1114       !llvm::has_single_bit<uint32_t>(MaskTy.getSizeInBits()))
1115     MaskTy = LLT::scalar(PtrTy.getSizeInBits());
1116   else {
1117     // Ensure that the type will fit the mask value.
1118     for (unsigned I = 0, E = B.Cases.size(); I != E; ++I) {
1119       if (!isUIntN(SwitchOpTy.getSizeInBits(), B.Cases[I].Mask)) {
1120         // Switch table case range are encoded into series of masks.
1121         // Just use pointer type, it's guaranteed to fit.
1122         MaskTy = LLT::scalar(PtrTy.getSizeInBits());
1123         break;
1124       }
1125     }
1126   }
1127   Register SubReg = RangeSub.getReg(0);
1128   if (SwitchOpTy != MaskTy)
1129     SubReg = MIB.buildZExtOrTrunc(MaskTy, SubReg).getReg(0);
1130 
1131   B.RegVT = getMVTForLLT(MaskTy);
1132   B.Reg = SubReg;
1133 
1134   MachineBasicBlock *MBB = B.Cases[0].ThisBB;
1135 
1136   if (!B.FallthroughUnreachable)
1137     addSuccessorWithProb(SwitchBB, B.Default, B.DefaultProb);
1138   addSuccessorWithProb(SwitchBB, MBB, B.Prob);
1139 
1140   SwitchBB->normalizeSuccProbs();
1141 
1142   if (!B.FallthroughUnreachable) {
1143     // Conditional branch to the default block.
1144     auto RangeCst = MIB.buildConstant(SwitchOpTy, B.Range);
1145     auto RangeCmp = MIB.buildICmp(CmpInst::Predicate::ICMP_UGT, LLT::scalar(1),
1146                                   RangeSub, RangeCst);
1147     MIB.buildBrCond(RangeCmp, *B.Default);
1148   }
1149 
1150   // Avoid emitting unnecessary branches to the next block.
1151   if (MBB != SwitchBB->getNextNode())
1152     MIB.buildBr(*MBB);
1153 }
1154 
1155 void IRTranslator::emitBitTestCase(SwitchCG::BitTestBlock &BB,
1156                                    MachineBasicBlock *NextMBB,
1157                                    BranchProbability BranchProbToNext,
1158                                    Register Reg, SwitchCG::BitTestCase &B,
1159                                    MachineBasicBlock *SwitchBB) {
1160   MachineIRBuilder &MIB = *CurBuilder;
1161   MIB.setMBB(*SwitchBB);
1162 
1163   LLT SwitchTy = getLLTForMVT(BB.RegVT);
1164   Register Cmp;
1165   unsigned PopCount = llvm::popcount(B.Mask);
1166   if (PopCount == 1) {
1167     // Testing for a single bit; just compare the shift count with what it
1168     // would need to be to shift a 1 bit in that position.
1169     auto MaskTrailingZeros =
1170         MIB.buildConstant(SwitchTy, llvm::countr_zero(B.Mask));
1171     Cmp =
1172         MIB.buildICmp(ICmpInst::ICMP_EQ, LLT::scalar(1), Reg, MaskTrailingZeros)
1173             .getReg(0);
1174   } else if (PopCount == BB.Range) {
1175     // There is only one zero bit in the range, test for it directly.
1176     auto MaskTrailingOnes =
1177         MIB.buildConstant(SwitchTy, llvm::countr_one(B.Mask));
1178     Cmp = MIB.buildICmp(CmpInst::ICMP_NE, LLT::scalar(1), Reg, MaskTrailingOnes)
1179               .getReg(0);
1180   } else {
1181     // Make desired shift.
1182     auto CstOne = MIB.buildConstant(SwitchTy, 1);
1183     auto SwitchVal = MIB.buildShl(SwitchTy, CstOne, Reg);
1184 
1185     // Emit bit tests and jumps.
1186     auto CstMask = MIB.buildConstant(SwitchTy, B.Mask);
1187     auto AndOp = MIB.buildAnd(SwitchTy, SwitchVal, CstMask);
1188     auto CstZero = MIB.buildConstant(SwitchTy, 0);
1189     Cmp = MIB.buildICmp(CmpInst::ICMP_NE, LLT::scalar(1), AndOp, CstZero)
1190               .getReg(0);
1191   }
1192 
1193   // The branch probability from SwitchBB to B.TargetBB is B.ExtraProb.
1194   addSuccessorWithProb(SwitchBB, B.TargetBB, B.ExtraProb);
1195   // The branch probability from SwitchBB to NextMBB is BranchProbToNext.
1196   addSuccessorWithProb(SwitchBB, NextMBB, BranchProbToNext);
1197   // It is not guaranteed that the sum of B.ExtraProb and BranchProbToNext is
1198   // one as they are relative probabilities (and thus work more like weights),
1199   // and hence we need to normalize them to let the sum of them become one.
1200   SwitchBB->normalizeSuccProbs();
1201 
1202   // Record the fact that the IR edge from the header to the bit test target
1203   // will go through our new block. Neeeded for PHIs to have nodes added.
1204   addMachineCFGPred({BB.Parent->getBasicBlock(), B.TargetBB->getBasicBlock()},
1205                     SwitchBB);
1206 
1207   MIB.buildBrCond(Cmp, *B.TargetBB);
1208 
1209   // Avoid emitting unnecessary branches to the next block.
1210   if (NextMBB != SwitchBB->getNextNode())
1211     MIB.buildBr(*NextMBB);
1212 }
1213 
1214 bool IRTranslator::lowerBitTestWorkItem(
1215     SwitchCG::SwitchWorkListItem W, MachineBasicBlock *SwitchMBB,
1216     MachineBasicBlock *CurMBB, MachineBasicBlock *DefaultMBB,
1217     MachineIRBuilder &MIB, MachineFunction::iterator BBI,
1218     BranchProbability DefaultProb, BranchProbability UnhandledProbs,
1219     SwitchCG::CaseClusterIt I, MachineBasicBlock *Fallthrough,
1220     bool FallthroughUnreachable) {
1221   using namespace SwitchCG;
1222   MachineFunction *CurMF = SwitchMBB->getParent();
1223   // FIXME: Optimize away range check based on pivot comparisons.
1224   BitTestBlock *BTB = &SL->BitTestCases[I->BTCasesIndex];
1225   // The bit test blocks haven't been inserted yet; insert them here.
1226   for (BitTestCase &BTC : BTB->Cases)
1227     CurMF->insert(BBI, BTC.ThisBB);
1228 
1229   // Fill in fields of the BitTestBlock.
1230   BTB->Parent = CurMBB;
1231   BTB->Default = Fallthrough;
1232 
1233   BTB->DefaultProb = UnhandledProbs;
1234   // If the cases in bit test don't form a contiguous range, we evenly
1235   // distribute the probability on the edge to Fallthrough to two
1236   // successors of CurMBB.
1237   if (!BTB->ContiguousRange) {
1238     BTB->Prob += DefaultProb / 2;
1239     BTB->DefaultProb -= DefaultProb / 2;
1240   }
1241 
1242   if (FallthroughUnreachable)
1243     BTB->FallthroughUnreachable = true;
1244 
1245   // If we're in the right place, emit the bit test header right now.
1246   if (CurMBB == SwitchMBB) {
1247     emitBitTestHeader(*BTB, SwitchMBB);
1248     BTB->Emitted = true;
1249   }
1250   return true;
1251 }
1252 
1253 bool IRTranslator::lowerSwitchWorkItem(SwitchCG::SwitchWorkListItem W,
1254                                        Value *Cond,
1255                                        MachineBasicBlock *SwitchMBB,
1256                                        MachineBasicBlock *DefaultMBB,
1257                                        MachineIRBuilder &MIB) {
1258   using namespace SwitchCG;
1259   MachineFunction *CurMF = FuncInfo.MF;
1260   MachineBasicBlock *NextMBB = nullptr;
1261   MachineFunction::iterator BBI(W.MBB);
1262   if (++BBI != FuncInfo.MF->end())
1263     NextMBB = &*BBI;
1264 
1265   if (EnableOpts) {
1266     // Here, we order cases by probability so the most likely case will be
1267     // checked first. However, two clusters can have the same probability in
1268     // which case their relative ordering is non-deterministic. So we use Low
1269     // as a tie-breaker as clusters are guaranteed to never overlap.
1270     llvm::sort(W.FirstCluster, W.LastCluster + 1,
1271                [](const CaseCluster &a, const CaseCluster &b) {
1272                  return a.Prob != b.Prob
1273                             ? a.Prob > b.Prob
1274                             : a.Low->getValue().slt(b.Low->getValue());
1275                });
1276 
1277     // Rearrange the case blocks so that the last one falls through if possible
1278     // without changing the order of probabilities.
1279     for (CaseClusterIt I = W.LastCluster; I > W.FirstCluster;) {
1280       --I;
1281       if (I->Prob > W.LastCluster->Prob)
1282         break;
1283       if (I->Kind == CC_Range && I->MBB == NextMBB) {
1284         std::swap(*I, *W.LastCluster);
1285         break;
1286       }
1287     }
1288   }
1289 
1290   // Compute total probability.
1291   BranchProbability DefaultProb = W.DefaultProb;
1292   BranchProbability UnhandledProbs = DefaultProb;
1293   for (CaseClusterIt I = W.FirstCluster; I <= W.LastCluster; ++I)
1294     UnhandledProbs += I->Prob;
1295 
1296   MachineBasicBlock *CurMBB = W.MBB;
1297   for (CaseClusterIt I = W.FirstCluster, E = W.LastCluster; I <= E; ++I) {
1298     bool FallthroughUnreachable = false;
1299     MachineBasicBlock *Fallthrough;
1300     if (I == W.LastCluster) {
1301       // For the last cluster, fall through to the default destination.
1302       Fallthrough = DefaultMBB;
1303       FallthroughUnreachable = isa<UnreachableInst>(
1304           DefaultMBB->getBasicBlock()->getFirstNonPHIOrDbg());
1305     } else {
1306       Fallthrough = CurMF->CreateMachineBasicBlock(CurMBB->getBasicBlock());
1307       CurMF->insert(BBI, Fallthrough);
1308     }
1309     UnhandledProbs -= I->Prob;
1310 
1311     switch (I->Kind) {
1312     case CC_BitTests: {
1313       if (!lowerBitTestWorkItem(W, SwitchMBB, CurMBB, DefaultMBB, MIB, BBI,
1314                                 DefaultProb, UnhandledProbs, I, Fallthrough,
1315                                 FallthroughUnreachable)) {
1316         LLVM_DEBUG(dbgs() << "Failed to lower bit test for switch");
1317         return false;
1318       }
1319       break;
1320     }
1321 
1322     case CC_JumpTable: {
1323       if (!lowerJumpTableWorkItem(W, SwitchMBB, CurMBB, DefaultMBB, MIB, BBI,
1324                                   UnhandledProbs, I, Fallthrough,
1325                                   FallthroughUnreachable)) {
1326         LLVM_DEBUG(dbgs() << "Failed to lower jump table");
1327         return false;
1328       }
1329       break;
1330     }
1331     case CC_Range: {
1332       if (!lowerSwitchRangeWorkItem(I, Cond, Fallthrough,
1333                                     FallthroughUnreachable, UnhandledProbs,
1334                                     CurMBB, MIB, SwitchMBB)) {
1335         LLVM_DEBUG(dbgs() << "Failed to lower switch range");
1336         return false;
1337       }
1338       break;
1339     }
1340     }
1341     CurMBB = Fallthrough;
1342   }
1343 
1344   return true;
1345 }
1346 
1347 bool IRTranslator::translateIndirectBr(const User &U,
1348                                        MachineIRBuilder &MIRBuilder) {
1349   const IndirectBrInst &BrInst = cast<IndirectBrInst>(U);
1350 
1351   const Register Tgt = getOrCreateVReg(*BrInst.getAddress());
1352   MIRBuilder.buildBrIndirect(Tgt);
1353 
1354   // Link successors.
1355   SmallPtrSet<const BasicBlock *, 32> AddedSuccessors;
1356   MachineBasicBlock &CurBB = MIRBuilder.getMBB();
1357   for (const BasicBlock *Succ : successors(&BrInst)) {
1358     // It's legal for indirectbr instructions to have duplicate blocks in the
1359     // destination list. We don't allow this in MIR. Skip anything that's
1360     // already a successor.
1361     if (!AddedSuccessors.insert(Succ).second)
1362       continue;
1363     CurBB.addSuccessor(&getMBB(*Succ));
1364   }
1365 
1366   return true;
1367 }
1368 
1369 static bool isSwiftError(const Value *V) {
1370   if (auto Arg = dyn_cast<Argument>(V))
1371     return Arg->hasSwiftErrorAttr();
1372   if (auto AI = dyn_cast<AllocaInst>(V))
1373     return AI->isSwiftError();
1374   return false;
1375 }
1376 
1377 bool IRTranslator::translateLoad(const User &U, MachineIRBuilder &MIRBuilder) {
1378   const LoadInst &LI = cast<LoadInst>(U);
1379   TypeSize StoreSize = DL->getTypeStoreSize(LI.getType());
1380   if (StoreSize.isZero())
1381     return true;
1382 
1383   ArrayRef<Register> Regs = getOrCreateVRegs(LI);
1384   ArrayRef<uint64_t> Offsets = *VMap.getOffsets(LI);
1385   Register Base = getOrCreateVReg(*LI.getPointerOperand());
1386   AAMDNodes AAInfo = LI.getAAMetadata();
1387 
1388   const Value *Ptr = LI.getPointerOperand();
1389   Type *OffsetIRTy = DL->getIndexType(Ptr->getType());
1390   LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL);
1391 
1392   if (CLI->supportSwiftError() && isSwiftError(Ptr)) {
1393     assert(Regs.size() == 1 && "swifterror should be single pointer");
1394     Register VReg =
1395         SwiftError.getOrCreateVRegUseAt(&LI, &MIRBuilder.getMBB(), Ptr);
1396     MIRBuilder.buildCopy(Regs[0], VReg);
1397     return true;
1398   }
1399 
1400   MachineMemOperand::Flags Flags =
1401       TLI->getLoadMemOperandFlags(LI, *DL, AC, LibInfo);
1402   if (AA && !(Flags & MachineMemOperand::MOInvariant)) {
1403     if (AA->pointsToConstantMemory(
1404             MemoryLocation(Ptr, LocationSize::precise(StoreSize), AAInfo))) {
1405       Flags |= MachineMemOperand::MOInvariant;
1406     }
1407   }
1408 
1409   const MDNode *Ranges =
1410       Regs.size() == 1 ? LI.getMetadata(LLVMContext::MD_range) : nullptr;
1411   for (unsigned i = 0; i < Regs.size(); ++i) {
1412     Register Addr;
1413     MIRBuilder.materializePtrAdd(Addr, Base, OffsetTy, Offsets[i] / 8);
1414 
1415     MachinePointerInfo Ptr(LI.getPointerOperand(), Offsets[i] / 8);
1416     Align BaseAlign = getMemOpAlign(LI);
1417     auto MMO = MF->getMachineMemOperand(
1418         Ptr, Flags, MRI->getType(Regs[i]),
1419         commonAlignment(BaseAlign, Offsets[i] / 8), AAInfo, Ranges,
1420         LI.getSyncScopeID(), LI.getOrdering());
1421     MIRBuilder.buildLoad(Regs[i], Addr, *MMO);
1422   }
1423 
1424   return true;
1425 }
1426 
1427 bool IRTranslator::translateStore(const User &U, MachineIRBuilder &MIRBuilder) {
1428   const StoreInst &SI = cast<StoreInst>(U);
1429   if (DL->getTypeStoreSize(SI.getValueOperand()->getType()).isZero())
1430     return true;
1431 
1432   ArrayRef<Register> Vals = getOrCreateVRegs(*SI.getValueOperand());
1433   ArrayRef<uint64_t> Offsets = *VMap.getOffsets(*SI.getValueOperand());
1434   Register Base = getOrCreateVReg(*SI.getPointerOperand());
1435 
1436   Type *OffsetIRTy = DL->getIndexType(SI.getPointerOperandType());
1437   LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL);
1438 
1439   if (CLI->supportSwiftError() && isSwiftError(SI.getPointerOperand())) {
1440     assert(Vals.size() == 1 && "swifterror should be single pointer");
1441 
1442     Register VReg = SwiftError.getOrCreateVRegDefAt(&SI, &MIRBuilder.getMBB(),
1443                                                     SI.getPointerOperand());
1444     MIRBuilder.buildCopy(VReg, Vals[0]);
1445     return true;
1446   }
1447 
1448   MachineMemOperand::Flags Flags = TLI->getStoreMemOperandFlags(SI, *DL);
1449 
1450   for (unsigned i = 0; i < Vals.size(); ++i) {
1451     Register Addr;
1452     MIRBuilder.materializePtrAdd(Addr, Base, OffsetTy, Offsets[i] / 8);
1453 
1454     MachinePointerInfo Ptr(SI.getPointerOperand(), Offsets[i] / 8);
1455     Align BaseAlign = getMemOpAlign(SI);
1456     auto MMO = MF->getMachineMemOperand(
1457         Ptr, Flags, MRI->getType(Vals[i]),
1458         commonAlignment(BaseAlign, Offsets[i] / 8), SI.getAAMetadata(), nullptr,
1459         SI.getSyncScopeID(), SI.getOrdering());
1460     MIRBuilder.buildStore(Vals[i], Addr, *MMO);
1461   }
1462   return true;
1463 }
1464 
1465 static uint64_t getOffsetFromIndices(const User &U, const DataLayout &DL) {
1466   const Value *Src = U.getOperand(0);
1467   Type *Int32Ty = Type::getInt32Ty(U.getContext());
1468 
1469   // getIndexedOffsetInType is designed for GEPs, so the first index is the
1470   // usual array element rather than looking into the actual aggregate.
1471   SmallVector<Value *, 1> Indices;
1472   Indices.push_back(ConstantInt::get(Int32Ty, 0));
1473 
1474   if (const ExtractValueInst *EVI = dyn_cast<ExtractValueInst>(&U)) {
1475     for (auto Idx : EVI->indices())
1476       Indices.push_back(ConstantInt::get(Int32Ty, Idx));
1477   } else if (const InsertValueInst *IVI = dyn_cast<InsertValueInst>(&U)) {
1478     for (auto Idx : IVI->indices())
1479       Indices.push_back(ConstantInt::get(Int32Ty, Idx));
1480   } else {
1481     for (Value *Op : drop_begin(U.operands()))
1482       Indices.push_back(Op);
1483   }
1484 
1485   return 8 * static_cast<uint64_t>(
1486                  DL.getIndexedOffsetInType(Src->getType(), Indices));
1487 }
1488 
1489 bool IRTranslator::translateExtractValue(const User &U,
1490                                          MachineIRBuilder &MIRBuilder) {
1491   const Value *Src = U.getOperand(0);
1492   uint64_t Offset = getOffsetFromIndices(U, *DL);
1493   ArrayRef<Register> SrcRegs = getOrCreateVRegs(*Src);
1494   ArrayRef<uint64_t> Offsets = *VMap.getOffsets(*Src);
1495   unsigned Idx = llvm::lower_bound(Offsets, Offset) - Offsets.begin();
1496   auto &DstRegs = allocateVRegs(U);
1497 
1498   for (unsigned i = 0; i < DstRegs.size(); ++i)
1499     DstRegs[i] = SrcRegs[Idx++];
1500 
1501   return true;
1502 }
1503 
1504 bool IRTranslator::translateInsertValue(const User &U,
1505                                         MachineIRBuilder &MIRBuilder) {
1506   const Value *Src = U.getOperand(0);
1507   uint64_t Offset = getOffsetFromIndices(U, *DL);
1508   auto &DstRegs = allocateVRegs(U);
1509   ArrayRef<uint64_t> DstOffsets = *VMap.getOffsets(U);
1510   ArrayRef<Register> SrcRegs = getOrCreateVRegs(*Src);
1511   ArrayRef<Register> InsertedRegs = getOrCreateVRegs(*U.getOperand(1));
1512   auto *InsertedIt = InsertedRegs.begin();
1513 
1514   for (unsigned i = 0; i < DstRegs.size(); ++i) {
1515     if (DstOffsets[i] >= Offset && InsertedIt != InsertedRegs.end())
1516       DstRegs[i] = *InsertedIt++;
1517     else
1518       DstRegs[i] = SrcRegs[i];
1519   }
1520 
1521   return true;
1522 }
1523 
1524 bool IRTranslator::translateSelect(const User &U,
1525                                    MachineIRBuilder &MIRBuilder) {
1526   Register Tst = getOrCreateVReg(*U.getOperand(0));
1527   ArrayRef<Register> ResRegs = getOrCreateVRegs(U);
1528   ArrayRef<Register> Op0Regs = getOrCreateVRegs(*U.getOperand(1));
1529   ArrayRef<Register> Op1Regs = getOrCreateVRegs(*U.getOperand(2));
1530 
1531   uint32_t Flags = 0;
1532   if (const SelectInst *SI = dyn_cast<SelectInst>(&U))
1533     Flags = MachineInstr::copyFlagsFromInstruction(*SI);
1534 
1535   for (unsigned i = 0; i < ResRegs.size(); ++i) {
1536     MIRBuilder.buildSelect(ResRegs[i], Tst, Op0Regs[i], Op1Regs[i], Flags);
1537   }
1538 
1539   return true;
1540 }
1541 
1542 bool IRTranslator::translateCopy(const User &U, const Value &V,
1543                                  MachineIRBuilder &MIRBuilder) {
1544   Register Src = getOrCreateVReg(V);
1545   auto &Regs = *VMap.getVRegs(U);
1546   if (Regs.empty()) {
1547     Regs.push_back(Src);
1548     VMap.getOffsets(U)->push_back(0);
1549   } else {
1550     // If we already assigned a vreg for this instruction, we can't change that.
1551     // Emit a copy to satisfy the users we already emitted.
1552     MIRBuilder.buildCopy(Regs[0], Src);
1553   }
1554   return true;
1555 }
1556 
1557 bool IRTranslator::translateBitCast(const User &U,
1558                                     MachineIRBuilder &MIRBuilder) {
1559   // If we're bitcasting to the source type, we can reuse the source vreg.
1560   if (getLLTForType(*U.getOperand(0)->getType(), *DL) ==
1561       getLLTForType(*U.getType(), *DL)) {
1562     // If the source is a ConstantInt then it was probably created by
1563     // ConstantHoisting and we should leave it alone.
1564     if (isa<ConstantInt>(U.getOperand(0)))
1565       return translateCast(TargetOpcode::G_CONSTANT_FOLD_BARRIER, U,
1566                            MIRBuilder);
1567     return translateCopy(U, *U.getOperand(0), MIRBuilder);
1568   }
1569 
1570   return translateCast(TargetOpcode::G_BITCAST, U, MIRBuilder);
1571 }
1572 
1573 bool IRTranslator::translateCast(unsigned Opcode, const User &U,
1574                                  MachineIRBuilder &MIRBuilder) {
1575   if (containsBF16Type(U))
1576     return false;
1577 
1578   uint32_t Flags = 0;
1579   if (const Instruction *I = dyn_cast<Instruction>(&U))
1580     Flags = MachineInstr::copyFlagsFromInstruction(*I);
1581 
1582   Register Op = getOrCreateVReg(*U.getOperand(0));
1583   Register Res = getOrCreateVReg(U);
1584   MIRBuilder.buildInstr(Opcode, {Res}, {Op}, Flags);
1585   return true;
1586 }
1587 
1588 bool IRTranslator::translateGetElementPtr(const User &U,
1589                                           MachineIRBuilder &MIRBuilder) {
1590   Value &Op0 = *U.getOperand(0);
1591   Register BaseReg = getOrCreateVReg(Op0);
1592   Type *PtrIRTy = Op0.getType();
1593   LLT PtrTy = getLLTForType(*PtrIRTy, *DL);
1594   Type *OffsetIRTy = DL->getIndexType(PtrIRTy);
1595   LLT OffsetTy = getLLTForType(*OffsetIRTy, *DL);
1596 
1597   uint32_t Flags = 0;
1598   if (const Instruction *I = dyn_cast<Instruction>(&U))
1599     Flags = MachineInstr::copyFlagsFromInstruction(*I);
1600 
1601   // Normalize Vector GEP - all scalar operands should be converted to the
1602   // splat vector.
1603   unsigned VectorWidth = 0;
1604 
1605   // True if we should use a splat vector; using VectorWidth alone is not
1606   // sufficient.
1607   bool WantSplatVector = false;
1608   if (auto *VT = dyn_cast<VectorType>(U.getType())) {
1609     VectorWidth = cast<FixedVectorType>(VT)->getNumElements();
1610     // We don't produce 1 x N vectors; those are treated as scalars.
1611     WantSplatVector = VectorWidth > 1;
1612   }
1613 
1614   // We might need to splat the base pointer into a vector if the offsets
1615   // are vectors.
1616   if (WantSplatVector && !PtrTy.isVector()) {
1617     BaseReg = MIRBuilder
1618                   .buildSplatBuildVector(LLT::fixed_vector(VectorWidth, PtrTy),
1619                                          BaseReg)
1620                   .getReg(0);
1621     PtrIRTy = FixedVectorType::get(PtrIRTy, VectorWidth);
1622     PtrTy = getLLTForType(*PtrIRTy, *DL);
1623     OffsetIRTy = DL->getIndexType(PtrIRTy);
1624     OffsetTy = getLLTForType(*OffsetIRTy, *DL);
1625   }
1626 
1627   int64_t Offset = 0;
1628   for (gep_type_iterator GTI = gep_type_begin(&U), E = gep_type_end(&U);
1629        GTI != E; ++GTI) {
1630     const Value *Idx = GTI.getOperand();
1631     if (StructType *StTy = GTI.getStructTypeOrNull()) {
1632       unsigned Field = cast<Constant>(Idx)->getUniqueInteger().getZExtValue();
1633       Offset += DL->getStructLayout(StTy)->getElementOffset(Field);
1634       continue;
1635     } else {
1636       uint64_t ElementSize = GTI.getSequentialElementStride(*DL);
1637 
1638       // If this is a scalar constant or a splat vector of constants,
1639       // handle it quickly.
1640       if (const auto *CI = dyn_cast<ConstantInt>(Idx)) {
1641         if (std::optional<int64_t> Val = CI->getValue().trySExtValue()) {
1642           Offset += ElementSize * *Val;
1643           continue;
1644         }
1645       }
1646 
1647       if (Offset != 0) {
1648         auto OffsetMIB = MIRBuilder.buildConstant({OffsetTy}, Offset);
1649         BaseReg = MIRBuilder.buildPtrAdd(PtrTy, BaseReg, OffsetMIB.getReg(0))
1650                       .getReg(0);
1651         Offset = 0;
1652       }
1653 
1654       Register IdxReg = getOrCreateVReg(*Idx);
1655       LLT IdxTy = MRI->getType(IdxReg);
1656       if (IdxTy != OffsetTy) {
1657         if (!IdxTy.isVector() && WantSplatVector) {
1658           IdxReg = MIRBuilder
1659                        .buildSplatBuildVector(OffsetTy.changeElementType(IdxTy),
1660                                               IdxReg)
1661                        .getReg(0);
1662         }
1663 
1664         IdxReg = MIRBuilder.buildSExtOrTrunc(OffsetTy, IdxReg).getReg(0);
1665       }
1666 
1667       // N = N + Idx * ElementSize;
1668       // Avoid doing it for ElementSize of 1.
1669       Register GepOffsetReg;
1670       if (ElementSize != 1) {
1671         auto ElementSizeMIB = MIRBuilder.buildConstant(
1672             getLLTForType(*OffsetIRTy, *DL), ElementSize);
1673         GepOffsetReg =
1674             MIRBuilder.buildMul(OffsetTy, IdxReg, ElementSizeMIB).getReg(0);
1675       } else
1676         GepOffsetReg = IdxReg;
1677 
1678       BaseReg = MIRBuilder.buildPtrAdd(PtrTy, BaseReg, GepOffsetReg).getReg(0);
1679     }
1680   }
1681 
1682   if (Offset != 0) {
1683     auto OffsetMIB =
1684         MIRBuilder.buildConstant(OffsetTy, Offset);
1685 
1686     if (int64_t(Offset) >= 0 && cast<GEPOperator>(U).isInBounds())
1687       Flags |= MachineInstr::MIFlag::NoUWrap;
1688 
1689     MIRBuilder.buildPtrAdd(getOrCreateVReg(U), BaseReg, OffsetMIB.getReg(0),
1690                            Flags);
1691     return true;
1692   }
1693 
1694   MIRBuilder.buildCopy(getOrCreateVReg(U), BaseReg);
1695   return true;
1696 }
1697 
1698 bool IRTranslator::translateMemFunc(const CallInst &CI,
1699                                     MachineIRBuilder &MIRBuilder,
1700                                     unsigned Opcode) {
1701   const Value *SrcPtr = CI.getArgOperand(1);
1702   // If the source is undef, then just emit a nop.
1703   if (isa<UndefValue>(SrcPtr))
1704     return true;
1705 
1706   SmallVector<Register, 3> SrcRegs;
1707 
1708   unsigned MinPtrSize = UINT_MAX;
1709   for (auto AI = CI.arg_begin(), AE = CI.arg_end(); std::next(AI) != AE; ++AI) {
1710     Register SrcReg = getOrCreateVReg(**AI);
1711     LLT SrcTy = MRI->getType(SrcReg);
1712     if (SrcTy.isPointer())
1713       MinPtrSize = std::min<unsigned>(SrcTy.getSizeInBits(), MinPtrSize);
1714     SrcRegs.push_back(SrcReg);
1715   }
1716 
1717   LLT SizeTy = LLT::scalar(MinPtrSize);
1718 
1719   // The size operand should be the minimum of the pointer sizes.
1720   Register &SizeOpReg = SrcRegs[SrcRegs.size() - 1];
1721   if (MRI->getType(SizeOpReg) != SizeTy)
1722     SizeOpReg = MIRBuilder.buildZExtOrTrunc(SizeTy, SizeOpReg).getReg(0);
1723 
1724   auto ICall = MIRBuilder.buildInstr(Opcode);
1725   for (Register SrcReg : SrcRegs)
1726     ICall.addUse(SrcReg);
1727 
1728   Align DstAlign;
1729   Align SrcAlign;
1730   unsigned IsVol =
1731       cast<ConstantInt>(CI.getArgOperand(CI.arg_size() - 1))->getZExtValue();
1732 
1733   ConstantInt *CopySize = nullptr;
1734 
1735   if (auto *MCI = dyn_cast<MemCpyInst>(&CI)) {
1736     DstAlign = MCI->getDestAlign().valueOrOne();
1737     SrcAlign = MCI->getSourceAlign().valueOrOne();
1738     CopySize = dyn_cast<ConstantInt>(MCI->getArgOperand(2));
1739   } else if (auto *MCI = dyn_cast<MemCpyInlineInst>(&CI)) {
1740     DstAlign = MCI->getDestAlign().valueOrOne();
1741     SrcAlign = MCI->getSourceAlign().valueOrOne();
1742     CopySize = dyn_cast<ConstantInt>(MCI->getArgOperand(2));
1743   } else if (auto *MMI = dyn_cast<MemMoveInst>(&CI)) {
1744     DstAlign = MMI->getDestAlign().valueOrOne();
1745     SrcAlign = MMI->getSourceAlign().valueOrOne();
1746     CopySize = dyn_cast<ConstantInt>(MMI->getArgOperand(2));
1747   } else {
1748     auto *MSI = cast<MemSetInst>(&CI);
1749     DstAlign = MSI->getDestAlign().valueOrOne();
1750   }
1751 
1752   if (Opcode != TargetOpcode::G_MEMCPY_INLINE) {
1753     // We need to propagate the tail call flag from the IR inst as an argument.
1754     // Otherwise, we have to pessimize and assume later that we cannot tail call
1755     // any memory intrinsics.
1756     ICall.addImm(CI.isTailCall() ? 1 : 0);
1757   }
1758 
1759   // Create mem operands to store the alignment and volatile info.
1760   MachineMemOperand::Flags LoadFlags = MachineMemOperand::MOLoad;
1761   MachineMemOperand::Flags StoreFlags = MachineMemOperand::MOStore;
1762   if (IsVol) {
1763     LoadFlags |= MachineMemOperand::MOVolatile;
1764     StoreFlags |= MachineMemOperand::MOVolatile;
1765   }
1766 
1767   AAMDNodes AAInfo = CI.getAAMetadata();
1768   if (AA && CopySize &&
1769       AA->pointsToConstantMemory(MemoryLocation(
1770           SrcPtr, LocationSize::precise(CopySize->getZExtValue()), AAInfo))) {
1771     LoadFlags |= MachineMemOperand::MOInvariant;
1772 
1773     // FIXME: pointsToConstantMemory probably does not imply dereferenceable,
1774     // but the previous usage implied it did. Probably should check
1775     // isDereferenceableAndAlignedPointer.
1776     LoadFlags |= MachineMemOperand::MODereferenceable;
1777   }
1778 
1779   ICall.addMemOperand(
1780       MF->getMachineMemOperand(MachinePointerInfo(CI.getArgOperand(0)),
1781                                StoreFlags, 1, DstAlign, AAInfo));
1782   if (Opcode != TargetOpcode::G_MEMSET)
1783     ICall.addMemOperand(MF->getMachineMemOperand(
1784         MachinePointerInfo(SrcPtr), LoadFlags, 1, SrcAlign, AAInfo));
1785 
1786   return true;
1787 }
1788 
1789 bool IRTranslator::translateTrap(const CallInst &CI,
1790                                  MachineIRBuilder &MIRBuilder,
1791                                  unsigned Opcode) {
1792   StringRef TrapFuncName =
1793       CI.getAttributes().getFnAttr("trap-func-name").getValueAsString();
1794   if (TrapFuncName.empty()) {
1795     if (Opcode == TargetOpcode::G_UBSANTRAP) {
1796       uint64_t Code = cast<ConstantInt>(CI.getOperand(0))->getZExtValue();
1797       MIRBuilder.buildInstr(Opcode, {}, ArrayRef<llvm::SrcOp>{Code});
1798     } else {
1799       MIRBuilder.buildInstr(Opcode);
1800     }
1801     return true;
1802   }
1803 
1804   CallLowering::CallLoweringInfo Info;
1805   if (Opcode == TargetOpcode::G_UBSANTRAP)
1806     Info.OrigArgs.push_back({getOrCreateVRegs(*CI.getArgOperand(0)),
1807                              CI.getArgOperand(0)->getType(), 0});
1808 
1809   Info.Callee = MachineOperand::CreateES(TrapFuncName.data());
1810   Info.CB = &CI;
1811   Info.OrigRet = {Register(), Type::getVoidTy(CI.getContext()), 0};
1812   return CLI->lowerCall(MIRBuilder, Info);
1813 }
1814 
1815 bool IRTranslator::translateVectorInterleave2Intrinsic(
1816     const CallInst &CI, MachineIRBuilder &MIRBuilder) {
1817   assert(CI.getIntrinsicID() == Intrinsic::vector_interleave2 &&
1818          "This function can only be called on the interleave2 intrinsic!");
1819   // Canonicalize interleave2 to G_SHUFFLE_VECTOR (similar to SelectionDAG).
1820   Register Op0 = getOrCreateVReg(*CI.getOperand(0));
1821   Register Op1 = getOrCreateVReg(*CI.getOperand(1));
1822   Register Res = getOrCreateVReg(CI);
1823 
1824   LLT OpTy = MRI->getType(Op0);
1825   MIRBuilder.buildShuffleVector(Res, Op0, Op1,
1826                                 createInterleaveMask(OpTy.getNumElements(), 2));
1827 
1828   return true;
1829 }
1830 
1831 bool IRTranslator::translateVectorDeinterleave2Intrinsic(
1832     const CallInst &CI, MachineIRBuilder &MIRBuilder) {
1833   assert(CI.getIntrinsicID() == Intrinsic::vector_deinterleave2 &&
1834          "This function can only be called on the deinterleave2 intrinsic!");
1835   // Canonicalize deinterleave2 to shuffles that extract sub-vectors (similar to
1836   // SelectionDAG).
1837   Register Op = getOrCreateVReg(*CI.getOperand(0));
1838   auto Undef = MIRBuilder.buildUndef(MRI->getType(Op));
1839   ArrayRef<Register> Res = getOrCreateVRegs(CI);
1840 
1841   LLT ResTy = MRI->getType(Res[0]);
1842   MIRBuilder.buildShuffleVector(Res[0], Op, Undef,
1843                                 createStrideMask(0, 2, ResTy.getNumElements()));
1844   MIRBuilder.buildShuffleVector(Res[1], Op, Undef,
1845                                 createStrideMask(1, 2, ResTy.getNumElements()));
1846 
1847   return true;
1848 }
1849 
1850 void IRTranslator::getStackGuard(Register DstReg,
1851                                  MachineIRBuilder &MIRBuilder) {
1852   const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo();
1853   MRI->setRegClass(DstReg, TRI->getPointerRegClass(*MF));
1854   auto MIB =
1855       MIRBuilder.buildInstr(TargetOpcode::LOAD_STACK_GUARD, {DstReg}, {});
1856 
1857   Value *Global = TLI->getSDagStackGuard(*MF->getFunction().getParent());
1858   if (!Global)
1859     return;
1860 
1861   unsigned AddrSpace = Global->getType()->getPointerAddressSpace();
1862   LLT PtrTy = LLT::pointer(AddrSpace, DL->getPointerSizeInBits(AddrSpace));
1863 
1864   MachinePointerInfo MPInfo(Global);
1865   auto Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOInvariant |
1866                MachineMemOperand::MODereferenceable;
1867   MachineMemOperand *MemRef = MF->getMachineMemOperand(
1868       MPInfo, Flags, PtrTy, DL->getPointerABIAlignment(AddrSpace));
1869   MIB.setMemRefs({MemRef});
1870 }
1871 
1872 bool IRTranslator::translateOverflowIntrinsic(const CallInst &CI, unsigned Op,
1873                                               MachineIRBuilder &MIRBuilder) {
1874   ArrayRef<Register> ResRegs = getOrCreateVRegs(CI);
1875   MIRBuilder.buildInstr(
1876       Op, {ResRegs[0], ResRegs[1]},
1877       {getOrCreateVReg(*CI.getOperand(0)), getOrCreateVReg(*CI.getOperand(1))});
1878 
1879   return true;
1880 }
1881 
1882 bool IRTranslator::translateFixedPointIntrinsic(unsigned Op, const CallInst &CI,
1883                                                 MachineIRBuilder &MIRBuilder) {
1884   Register Dst = getOrCreateVReg(CI);
1885   Register Src0 = getOrCreateVReg(*CI.getOperand(0));
1886   Register Src1 = getOrCreateVReg(*CI.getOperand(1));
1887   uint64_t Scale = cast<ConstantInt>(CI.getOperand(2))->getZExtValue();
1888   MIRBuilder.buildInstr(Op, {Dst}, { Src0, Src1, Scale });
1889   return true;
1890 }
1891 
1892 unsigned IRTranslator::getSimpleIntrinsicOpcode(Intrinsic::ID ID) {
1893   switch (ID) {
1894     default:
1895       break;
1896     case Intrinsic::acos:
1897       return TargetOpcode::G_FACOS;
1898     case Intrinsic::asin:
1899       return TargetOpcode::G_FASIN;
1900     case Intrinsic::atan:
1901       return TargetOpcode::G_FATAN;
1902     case Intrinsic::atan2:
1903       return TargetOpcode::G_FATAN2;
1904     case Intrinsic::bswap:
1905       return TargetOpcode::G_BSWAP;
1906     case Intrinsic::bitreverse:
1907       return TargetOpcode::G_BITREVERSE;
1908     case Intrinsic::fshl:
1909       return TargetOpcode::G_FSHL;
1910     case Intrinsic::fshr:
1911       return TargetOpcode::G_FSHR;
1912     case Intrinsic::ceil:
1913       return TargetOpcode::G_FCEIL;
1914     case Intrinsic::cos:
1915       return TargetOpcode::G_FCOS;
1916     case Intrinsic::cosh:
1917       return TargetOpcode::G_FCOSH;
1918     case Intrinsic::ctpop:
1919       return TargetOpcode::G_CTPOP;
1920     case Intrinsic::exp:
1921       return TargetOpcode::G_FEXP;
1922     case Intrinsic::exp2:
1923       return TargetOpcode::G_FEXP2;
1924     case Intrinsic::exp10:
1925       return TargetOpcode::G_FEXP10;
1926     case Intrinsic::fabs:
1927       return TargetOpcode::G_FABS;
1928     case Intrinsic::copysign:
1929       return TargetOpcode::G_FCOPYSIGN;
1930     case Intrinsic::minnum:
1931       return TargetOpcode::G_FMINNUM;
1932     case Intrinsic::maxnum:
1933       return TargetOpcode::G_FMAXNUM;
1934     case Intrinsic::minimum:
1935       return TargetOpcode::G_FMINIMUM;
1936     case Intrinsic::maximum:
1937       return TargetOpcode::G_FMAXIMUM;
1938     case Intrinsic::canonicalize:
1939       return TargetOpcode::G_FCANONICALIZE;
1940     case Intrinsic::floor:
1941       return TargetOpcode::G_FFLOOR;
1942     case Intrinsic::fma:
1943       return TargetOpcode::G_FMA;
1944     case Intrinsic::log:
1945       return TargetOpcode::G_FLOG;
1946     case Intrinsic::log2:
1947       return TargetOpcode::G_FLOG2;
1948     case Intrinsic::log10:
1949       return TargetOpcode::G_FLOG10;
1950     case Intrinsic::ldexp:
1951       return TargetOpcode::G_FLDEXP;
1952     case Intrinsic::nearbyint:
1953       return TargetOpcode::G_FNEARBYINT;
1954     case Intrinsic::pow:
1955       return TargetOpcode::G_FPOW;
1956     case Intrinsic::powi:
1957       return TargetOpcode::G_FPOWI;
1958     case Intrinsic::rint:
1959       return TargetOpcode::G_FRINT;
1960     case Intrinsic::round:
1961       return TargetOpcode::G_INTRINSIC_ROUND;
1962     case Intrinsic::roundeven:
1963       return TargetOpcode::G_INTRINSIC_ROUNDEVEN;
1964     case Intrinsic::sin:
1965       return TargetOpcode::G_FSIN;
1966     case Intrinsic::sinh:
1967       return TargetOpcode::G_FSINH;
1968     case Intrinsic::sqrt:
1969       return TargetOpcode::G_FSQRT;
1970     case Intrinsic::tan:
1971       return TargetOpcode::G_FTAN;
1972     case Intrinsic::tanh:
1973       return TargetOpcode::G_FTANH;
1974     case Intrinsic::trunc:
1975       return TargetOpcode::G_INTRINSIC_TRUNC;
1976     case Intrinsic::readcyclecounter:
1977       return TargetOpcode::G_READCYCLECOUNTER;
1978     case Intrinsic::readsteadycounter:
1979       return TargetOpcode::G_READSTEADYCOUNTER;
1980     case Intrinsic::ptrmask:
1981       return TargetOpcode::G_PTRMASK;
1982     case Intrinsic::lrint:
1983       return TargetOpcode::G_INTRINSIC_LRINT;
1984     case Intrinsic::llrint:
1985       return TargetOpcode::G_INTRINSIC_LLRINT;
1986     // FADD/FMUL require checking the FMF, so are handled elsewhere.
1987     case Intrinsic::vector_reduce_fmin:
1988       return TargetOpcode::G_VECREDUCE_FMIN;
1989     case Intrinsic::vector_reduce_fmax:
1990       return TargetOpcode::G_VECREDUCE_FMAX;
1991     case Intrinsic::vector_reduce_fminimum:
1992       return TargetOpcode::G_VECREDUCE_FMINIMUM;
1993     case Intrinsic::vector_reduce_fmaximum:
1994       return TargetOpcode::G_VECREDUCE_FMAXIMUM;
1995     case Intrinsic::vector_reduce_add:
1996       return TargetOpcode::G_VECREDUCE_ADD;
1997     case Intrinsic::vector_reduce_mul:
1998       return TargetOpcode::G_VECREDUCE_MUL;
1999     case Intrinsic::vector_reduce_and:
2000       return TargetOpcode::G_VECREDUCE_AND;
2001     case Intrinsic::vector_reduce_or:
2002       return TargetOpcode::G_VECREDUCE_OR;
2003     case Intrinsic::vector_reduce_xor:
2004       return TargetOpcode::G_VECREDUCE_XOR;
2005     case Intrinsic::vector_reduce_smax:
2006       return TargetOpcode::G_VECREDUCE_SMAX;
2007     case Intrinsic::vector_reduce_smin:
2008       return TargetOpcode::G_VECREDUCE_SMIN;
2009     case Intrinsic::vector_reduce_umax:
2010       return TargetOpcode::G_VECREDUCE_UMAX;
2011     case Intrinsic::vector_reduce_umin:
2012       return TargetOpcode::G_VECREDUCE_UMIN;
2013     case Intrinsic::experimental_vector_compress:
2014       return TargetOpcode::G_VECTOR_COMPRESS;
2015     case Intrinsic::lround:
2016       return TargetOpcode::G_LROUND;
2017     case Intrinsic::llround:
2018       return TargetOpcode::G_LLROUND;
2019     case Intrinsic::get_fpenv:
2020       return TargetOpcode::G_GET_FPENV;
2021     case Intrinsic::get_fpmode:
2022       return TargetOpcode::G_GET_FPMODE;
2023   }
2024   return Intrinsic::not_intrinsic;
2025 }
2026 
2027 bool IRTranslator::translateSimpleIntrinsic(const CallInst &CI,
2028                                             Intrinsic::ID ID,
2029                                             MachineIRBuilder &MIRBuilder) {
2030 
2031   unsigned Op = getSimpleIntrinsicOpcode(ID);
2032 
2033   // Is this a simple intrinsic?
2034   if (Op == Intrinsic::not_intrinsic)
2035     return false;
2036 
2037   // Yes. Let's translate it.
2038   SmallVector<llvm::SrcOp, 4> VRegs;
2039   for (const auto &Arg : CI.args())
2040     VRegs.push_back(getOrCreateVReg(*Arg));
2041 
2042   MIRBuilder.buildInstr(Op, {getOrCreateVReg(CI)}, VRegs,
2043                         MachineInstr::copyFlagsFromInstruction(CI));
2044   return true;
2045 }
2046 
2047 // TODO: Include ConstainedOps.def when all strict instructions are defined.
2048 static unsigned getConstrainedOpcode(Intrinsic::ID ID) {
2049   switch (ID) {
2050   case Intrinsic::experimental_constrained_fadd:
2051     return TargetOpcode::G_STRICT_FADD;
2052   case Intrinsic::experimental_constrained_fsub:
2053     return TargetOpcode::G_STRICT_FSUB;
2054   case Intrinsic::experimental_constrained_fmul:
2055     return TargetOpcode::G_STRICT_FMUL;
2056   case Intrinsic::experimental_constrained_fdiv:
2057     return TargetOpcode::G_STRICT_FDIV;
2058   case Intrinsic::experimental_constrained_frem:
2059     return TargetOpcode::G_STRICT_FREM;
2060   case Intrinsic::experimental_constrained_fma:
2061     return TargetOpcode::G_STRICT_FMA;
2062   case Intrinsic::experimental_constrained_sqrt:
2063     return TargetOpcode::G_STRICT_FSQRT;
2064   case Intrinsic::experimental_constrained_ldexp:
2065     return TargetOpcode::G_STRICT_FLDEXP;
2066   default:
2067     return 0;
2068   }
2069 }
2070 
2071 bool IRTranslator::translateConstrainedFPIntrinsic(
2072   const ConstrainedFPIntrinsic &FPI, MachineIRBuilder &MIRBuilder) {
2073   fp::ExceptionBehavior EB = *FPI.getExceptionBehavior();
2074 
2075   unsigned Opcode = getConstrainedOpcode(FPI.getIntrinsicID());
2076   if (!Opcode)
2077     return false;
2078 
2079   uint32_t Flags = MachineInstr::copyFlagsFromInstruction(FPI);
2080   if (EB == fp::ExceptionBehavior::ebIgnore)
2081     Flags |= MachineInstr::NoFPExcept;
2082 
2083   SmallVector<llvm::SrcOp, 4> VRegs;
2084   for (unsigned I = 0, E = FPI.getNonMetadataArgCount(); I != E; ++I)
2085     VRegs.push_back(getOrCreateVReg(*FPI.getArgOperand(I)));
2086 
2087   MIRBuilder.buildInstr(Opcode, {getOrCreateVReg(FPI)}, VRegs, Flags);
2088   return true;
2089 }
2090 
2091 std::optional<MCRegister> IRTranslator::getArgPhysReg(Argument &Arg) {
2092   auto VRegs = getOrCreateVRegs(Arg);
2093   if (VRegs.size() != 1)
2094     return std::nullopt;
2095 
2096   // Arguments are lowered as a copy of a livein physical register.
2097   auto *VRegDef = MF->getRegInfo().getVRegDef(VRegs[0]);
2098   if (!VRegDef || !VRegDef->isCopy())
2099     return std::nullopt;
2100   return VRegDef->getOperand(1).getReg().asMCReg();
2101 }
2102 
2103 bool IRTranslator::translateIfEntryValueArgument(bool isDeclare, Value *Val,
2104                                                  const DILocalVariable *Var,
2105                                                  const DIExpression *Expr,
2106                                                  const DebugLoc &DL,
2107                                                  MachineIRBuilder &MIRBuilder) {
2108   auto *Arg = dyn_cast<Argument>(Val);
2109   if (!Arg)
2110     return false;
2111 
2112   if (!Expr->isEntryValue())
2113     return false;
2114 
2115   std::optional<MCRegister> PhysReg = getArgPhysReg(*Arg);
2116   if (!PhysReg) {
2117     LLVM_DEBUG(dbgs() << "Dropping dbg." << (isDeclare ? "declare" : "value")
2118                       << ": expression is entry_value but "
2119                       << "couldn't find a physical register\n");
2120     LLVM_DEBUG(dbgs() << *Var << "\n");
2121     return true;
2122   }
2123 
2124   if (isDeclare) {
2125     // Append an op deref to account for the fact that this is a dbg_declare.
2126     Expr = DIExpression::append(Expr, dwarf::DW_OP_deref);
2127     MF->setVariableDbgInfo(Var, Expr, *PhysReg, DL);
2128   } else {
2129     MIRBuilder.buildDirectDbgValue(*PhysReg, Var, Expr);
2130   }
2131 
2132   return true;
2133 }
2134 
2135 static unsigned getConvOpcode(Intrinsic::ID ID) {
2136   switch (ID) {
2137   default:
2138     llvm_unreachable("Unexpected intrinsic");
2139   case Intrinsic::experimental_convergence_anchor:
2140     return TargetOpcode::CONVERGENCECTRL_ANCHOR;
2141   case Intrinsic::experimental_convergence_entry:
2142     return TargetOpcode::CONVERGENCECTRL_ENTRY;
2143   case Intrinsic::experimental_convergence_loop:
2144     return TargetOpcode::CONVERGENCECTRL_LOOP;
2145   }
2146 }
2147 
2148 bool IRTranslator::translateConvergenceControlIntrinsic(
2149     const CallInst &CI, Intrinsic::ID ID, MachineIRBuilder &MIRBuilder) {
2150   MachineInstrBuilder MIB = MIRBuilder.buildInstr(getConvOpcode(ID));
2151   Register OutputReg = getOrCreateConvergenceTokenVReg(CI);
2152   MIB.addDef(OutputReg);
2153 
2154   if (ID == Intrinsic::experimental_convergence_loop) {
2155     auto Bundle = CI.getOperandBundle(LLVMContext::OB_convergencectrl);
2156     assert(Bundle && "Expected a convergence control token.");
2157     Register InputReg =
2158         getOrCreateConvergenceTokenVReg(*Bundle->Inputs[0].get());
2159     MIB.addUse(InputReg);
2160   }
2161 
2162   return true;
2163 }
2164 
2165 bool IRTranslator::translateKnownIntrinsic(const CallInst &CI, Intrinsic::ID ID,
2166                                            MachineIRBuilder &MIRBuilder) {
2167   if (auto *MI = dyn_cast<AnyMemIntrinsic>(&CI)) {
2168     if (ORE->enabled()) {
2169       if (MemoryOpRemark::canHandle(MI, *LibInfo)) {
2170         MemoryOpRemark R(*ORE, "gisel-irtranslator-memsize", *DL, *LibInfo);
2171         R.visit(MI);
2172       }
2173     }
2174   }
2175 
2176   // If this is a simple intrinsic (that is, we just need to add a def of
2177   // a vreg, and uses for each arg operand, then translate it.
2178   if (translateSimpleIntrinsic(CI, ID, MIRBuilder))
2179     return true;
2180 
2181   switch (ID) {
2182   default:
2183     break;
2184   case Intrinsic::lifetime_start:
2185   case Intrinsic::lifetime_end: {
2186     // No stack colouring in O0, discard region information.
2187     if (MF->getTarget().getOptLevel() == CodeGenOptLevel::None ||
2188         MF->getFunction().hasOptNone())
2189       return true;
2190 
2191     unsigned Op = ID == Intrinsic::lifetime_start ? TargetOpcode::LIFETIME_START
2192                                                   : TargetOpcode::LIFETIME_END;
2193 
2194     // Get the underlying objects for the location passed on the lifetime
2195     // marker.
2196     SmallVector<const Value *, 4> Allocas;
2197     getUnderlyingObjects(CI.getArgOperand(1), Allocas);
2198 
2199     // Iterate over each underlying object, creating lifetime markers for each
2200     // static alloca. Quit if we find a non-static alloca.
2201     for (const Value *V : Allocas) {
2202       const AllocaInst *AI = dyn_cast<AllocaInst>(V);
2203       if (!AI)
2204         continue;
2205 
2206       if (!AI->isStaticAlloca())
2207         return true;
2208 
2209       MIRBuilder.buildInstr(Op).addFrameIndex(getOrCreateFrameIndex(*AI));
2210     }
2211     return true;
2212   }
2213   case Intrinsic::fake_use: {
2214     SmallVector<llvm::SrcOp, 4> VRegs;
2215     for (const auto &Arg : CI.args())
2216       for (auto VReg : getOrCreateVRegs(*Arg))
2217         VRegs.push_back(VReg);
2218     MIRBuilder.buildInstr(TargetOpcode::FAKE_USE, {}, VRegs);
2219     MF->setHasFakeUses(true);
2220     return true;
2221   }
2222   case Intrinsic::dbg_declare: {
2223     const DbgDeclareInst &DI = cast<DbgDeclareInst>(CI);
2224     assert(DI.getVariable() && "Missing variable");
2225     translateDbgDeclareRecord(DI.getAddress(), DI.hasArgList(), DI.getVariable(),
2226                        DI.getExpression(), DI.getDebugLoc(), MIRBuilder);
2227     return true;
2228   }
2229   case Intrinsic::dbg_label: {
2230     const DbgLabelInst &DI = cast<DbgLabelInst>(CI);
2231     assert(DI.getLabel() && "Missing label");
2232 
2233     assert(DI.getLabel()->isValidLocationForIntrinsic(
2234                MIRBuilder.getDebugLoc()) &&
2235            "Expected inlined-at fields to agree");
2236 
2237     MIRBuilder.buildDbgLabel(DI.getLabel());
2238     return true;
2239   }
2240   case Intrinsic::vaend:
2241     // No target I know of cares about va_end. Certainly no in-tree target
2242     // does. Simplest intrinsic ever!
2243     return true;
2244   case Intrinsic::vastart: {
2245     Value *Ptr = CI.getArgOperand(0);
2246     unsigned ListSize = TLI->getVaListSizeInBits(*DL) / 8;
2247     Align Alignment = getKnownAlignment(Ptr, *DL);
2248 
2249     MIRBuilder.buildInstr(TargetOpcode::G_VASTART, {}, {getOrCreateVReg(*Ptr)})
2250         .addMemOperand(MF->getMachineMemOperand(MachinePointerInfo(Ptr),
2251                                                 MachineMemOperand::MOStore,
2252                                                 ListSize, Alignment));
2253     return true;
2254   }
2255   case Intrinsic::dbg_assign:
2256     // A dbg.assign is a dbg.value with more information about stack locations,
2257     // typically produced during optimisation of variables with leaked
2258     // addresses. We can treat it like a normal dbg_value intrinsic here; to
2259     // benefit from the full analysis of stack/SSA locations, GlobalISel would
2260     // need to register for and use the AssignmentTrackingAnalysis pass.
2261     [[fallthrough]];
2262   case Intrinsic::dbg_value: {
2263     // This form of DBG_VALUE is target-independent.
2264     const DbgValueInst &DI = cast<DbgValueInst>(CI);
2265     translateDbgValueRecord(DI.getValue(), DI.hasArgList(), DI.getVariable(),
2266                        DI.getExpression(), DI.getDebugLoc(), MIRBuilder);
2267     return true;
2268   }
2269   case Intrinsic::uadd_with_overflow:
2270     return translateOverflowIntrinsic(CI, TargetOpcode::G_UADDO, MIRBuilder);
2271   case Intrinsic::sadd_with_overflow:
2272     return translateOverflowIntrinsic(CI, TargetOpcode::G_SADDO, MIRBuilder);
2273   case Intrinsic::usub_with_overflow:
2274     return translateOverflowIntrinsic(CI, TargetOpcode::G_USUBO, MIRBuilder);
2275   case Intrinsic::ssub_with_overflow:
2276     return translateOverflowIntrinsic(CI, TargetOpcode::G_SSUBO, MIRBuilder);
2277   case Intrinsic::umul_with_overflow:
2278     return translateOverflowIntrinsic(CI, TargetOpcode::G_UMULO, MIRBuilder);
2279   case Intrinsic::smul_with_overflow:
2280     return translateOverflowIntrinsic(CI, TargetOpcode::G_SMULO, MIRBuilder);
2281   case Intrinsic::uadd_sat:
2282     return translateBinaryOp(TargetOpcode::G_UADDSAT, CI, MIRBuilder);
2283   case Intrinsic::sadd_sat:
2284     return translateBinaryOp(TargetOpcode::G_SADDSAT, CI, MIRBuilder);
2285   case Intrinsic::usub_sat:
2286     return translateBinaryOp(TargetOpcode::G_USUBSAT, CI, MIRBuilder);
2287   case Intrinsic::ssub_sat:
2288     return translateBinaryOp(TargetOpcode::G_SSUBSAT, CI, MIRBuilder);
2289   case Intrinsic::ushl_sat:
2290     return translateBinaryOp(TargetOpcode::G_USHLSAT, CI, MIRBuilder);
2291   case Intrinsic::sshl_sat:
2292     return translateBinaryOp(TargetOpcode::G_SSHLSAT, CI, MIRBuilder);
2293   case Intrinsic::umin:
2294     return translateBinaryOp(TargetOpcode::G_UMIN, CI, MIRBuilder);
2295   case Intrinsic::umax:
2296     return translateBinaryOp(TargetOpcode::G_UMAX, CI, MIRBuilder);
2297   case Intrinsic::smin:
2298     return translateBinaryOp(TargetOpcode::G_SMIN, CI, MIRBuilder);
2299   case Intrinsic::smax:
2300     return translateBinaryOp(TargetOpcode::G_SMAX, CI, MIRBuilder);
2301   case Intrinsic::abs:
2302     // TODO: Preserve "int min is poison" arg in GMIR?
2303     return translateUnaryOp(TargetOpcode::G_ABS, CI, MIRBuilder);
2304   case Intrinsic::smul_fix:
2305     return translateFixedPointIntrinsic(TargetOpcode::G_SMULFIX, CI, MIRBuilder);
2306   case Intrinsic::umul_fix:
2307     return translateFixedPointIntrinsic(TargetOpcode::G_UMULFIX, CI, MIRBuilder);
2308   case Intrinsic::smul_fix_sat:
2309     return translateFixedPointIntrinsic(TargetOpcode::G_SMULFIXSAT, CI, MIRBuilder);
2310   case Intrinsic::umul_fix_sat:
2311     return translateFixedPointIntrinsic(TargetOpcode::G_UMULFIXSAT, CI, MIRBuilder);
2312   case Intrinsic::sdiv_fix:
2313     return translateFixedPointIntrinsic(TargetOpcode::G_SDIVFIX, CI, MIRBuilder);
2314   case Intrinsic::udiv_fix:
2315     return translateFixedPointIntrinsic(TargetOpcode::G_UDIVFIX, CI, MIRBuilder);
2316   case Intrinsic::sdiv_fix_sat:
2317     return translateFixedPointIntrinsic(TargetOpcode::G_SDIVFIXSAT, CI, MIRBuilder);
2318   case Intrinsic::udiv_fix_sat:
2319     return translateFixedPointIntrinsic(TargetOpcode::G_UDIVFIXSAT, CI, MIRBuilder);
2320   case Intrinsic::fmuladd: {
2321     const TargetMachine &TM = MF->getTarget();
2322     Register Dst = getOrCreateVReg(CI);
2323     Register Op0 = getOrCreateVReg(*CI.getArgOperand(0));
2324     Register Op1 = getOrCreateVReg(*CI.getArgOperand(1));
2325     Register Op2 = getOrCreateVReg(*CI.getArgOperand(2));
2326     if (TM.Options.AllowFPOpFusion != FPOpFusion::Strict &&
2327         TLI->isFMAFasterThanFMulAndFAdd(*MF,
2328                                         TLI->getValueType(*DL, CI.getType()))) {
2329       // TODO: Revisit this to see if we should move this part of the
2330       // lowering to the combiner.
2331       MIRBuilder.buildFMA(Dst, Op0, Op1, Op2,
2332                           MachineInstr::copyFlagsFromInstruction(CI));
2333     } else {
2334       LLT Ty = getLLTForType(*CI.getType(), *DL);
2335       auto FMul = MIRBuilder.buildFMul(
2336           Ty, Op0, Op1, MachineInstr::copyFlagsFromInstruction(CI));
2337       MIRBuilder.buildFAdd(Dst, FMul, Op2,
2338                            MachineInstr::copyFlagsFromInstruction(CI));
2339     }
2340     return true;
2341   }
2342   case Intrinsic::convert_from_fp16:
2343     // FIXME: This intrinsic should probably be removed from the IR.
2344     MIRBuilder.buildFPExt(getOrCreateVReg(CI),
2345                           getOrCreateVReg(*CI.getArgOperand(0)),
2346                           MachineInstr::copyFlagsFromInstruction(CI));
2347     return true;
2348   case Intrinsic::convert_to_fp16:
2349     // FIXME: This intrinsic should probably be removed from the IR.
2350     MIRBuilder.buildFPTrunc(getOrCreateVReg(CI),
2351                             getOrCreateVReg(*CI.getArgOperand(0)),
2352                             MachineInstr::copyFlagsFromInstruction(CI));
2353     return true;
2354   case Intrinsic::frexp: {
2355     ArrayRef<Register> VRegs = getOrCreateVRegs(CI);
2356     MIRBuilder.buildFFrexp(VRegs[0], VRegs[1],
2357                            getOrCreateVReg(*CI.getArgOperand(0)),
2358                            MachineInstr::copyFlagsFromInstruction(CI));
2359     return true;
2360   }
2361   case Intrinsic::sincos: {
2362     ArrayRef<Register> VRegs = getOrCreateVRegs(CI);
2363     MIRBuilder.buildFSincos(VRegs[0], VRegs[1],
2364                             getOrCreateVReg(*CI.getArgOperand(0)),
2365                             MachineInstr::copyFlagsFromInstruction(CI));
2366     return true;
2367   }
2368   case Intrinsic::fptosi_sat:
2369     MIRBuilder.buildFPTOSI_SAT(getOrCreateVReg(CI),
2370                                getOrCreateVReg(*CI.getArgOperand(0)));
2371     return true;
2372   case Intrinsic::fptoui_sat:
2373     MIRBuilder.buildFPTOUI_SAT(getOrCreateVReg(CI),
2374                                getOrCreateVReg(*CI.getArgOperand(0)));
2375     return true;
2376   case Intrinsic::memcpy_inline:
2377     return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMCPY_INLINE);
2378   case Intrinsic::memcpy:
2379     return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMCPY);
2380   case Intrinsic::memmove:
2381     return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMMOVE);
2382   case Intrinsic::memset:
2383     return translateMemFunc(CI, MIRBuilder, TargetOpcode::G_MEMSET);
2384   case Intrinsic::eh_typeid_for: {
2385     GlobalValue *GV = ExtractTypeInfo(CI.getArgOperand(0));
2386     Register Reg = getOrCreateVReg(CI);
2387     unsigned TypeID = MF->getTypeIDFor(GV);
2388     MIRBuilder.buildConstant(Reg, TypeID);
2389     return true;
2390   }
2391   case Intrinsic::objectsize:
2392     llvm_unreachable("llvm.objectsize.* should have been lowered already");
2393 
2394   case Intrinsic::is_constant:
2395     llvm_unreachable("llvm.is.constant.* should have been lowered already");
2396 
2397   case Intrinsic::stackguard:
2398     getStackGuard(getOrCreateVReg(CI), MIRBuilder);
2399     return true;
2400   case Intrinsic::stackprotector: {
2401     LLT PtrTy = getLLTForType(*CI.getArgOperand(0)->getType(), *DL);
2402     Register GuardVal;
2403     if (TLI->useLoadStackGuardNode(*CI.getModule())) {
2404       GuardVal = MRI->createGenericVirtualRegister(PtrTy);
2405       getStackGuard(GuardVal, MIRBuilder);
2406     } else
2407       GuardVal = getOrCreateVReg(*CI.getArgOperand(0)); // The guard's value.
2408 
2409     AllocaInst *Slot = cast<AllocaInst>(CI.getArgOperand(1));
2410     int FI = getOrCreateFrameIndex(*Slot);
2411     MF->getFrameInfo().setStackProtectorIndex(FI);
2412 
2413     MIRBuilder.buildStore(
2414         GuardVal, getOrCreateVReg(*Slot),
2415         *MF->getMachineMemOperand(MachinePointerInfo::getFixedStack(*MF, FI),
2416                                   MachineMemOperand::MOStore |
2417                                       MachineMemOperand::MOVolatile,
2418                                   PtrTy, Align(8)));
2419     return true;
2420   }
2421   case Intrinsic::stacksave: {
2422     MIRBuilder.buildInstr(TargetOpcode::G_STACKSAVE, {getOrCreateVReg(CI)}, {});
2423     return true;
2424   }
2425   case Intrinsic::stackrestore: {
2426     MIRBuilder.buildInstr(TargetOpcode::G_STACKRESTORE, {},
2427                           {getOrCreateVReg(*CI.getArgOperand(0))});
2428     return true;
2429   }
2430   case Intrinsic::cttz:
2431   case Intrinsic::ctlz: {
2432     ConstantInt *Cst = cast<ConstantInt>(CI.getArgOperand(1));
2433     bool isTrailing = ID == Intrinsic::cttz;
2434     unsigned Opcode = isTrailing
2435                           ? Cst->isZero() ? TargetOpcode::G_CTTZ
2436                                           : TargetOpcode::G_CTTZ_ZERO_UNDEF
2437                           : Cst->isZero() ? TargetOpcode::G_CTLZ
2438                                           : TargetOpcode::G_CTLZ_ZERO_UNDEF;
2439     MIRBuilder.buildInstr(Opcode, {getOrCreateVReg(CI)},
2440                           {getOrCreateVReg(*CI.getArgOperand(0))});
2441     return true;
2442   }
2443   case Intrinsic::invariant_start: {
2444     LLT PtrTy = getLLTForType(*CI.getArgOperand(0)->getType(), *DL);
2445     Register Undef = MRI->createGenericVirtualRegister(PtrTy);
2446     MIRBuilder.buildUndef(Undef);
2447     return true;
2448   }
2449   case Intrinsic::invariant_end:
2450     return true;
2451   case Intrinsic::expect:
2452   case Intrinsic::expect_with_probability:
2453   case Intrinsic::annotation:
2454   case Intrinsic::ptr_annotation:
2455   case Intrinsic::launder_invariant_group:
2456   case Intrinsic::strip_invariant_group: {
2457     // Drop the intrinsic, but forward the value.
2458     MIRBuilder.buildCopy(getOrCreateVReg(CI),
2459                          getOrCreateVReg(*CI.getArgOperand(0)));
2460     return true;
2461   }
2462   case Intrinsic::assume:
2463   case Intrinsic::experimental_noalias_scope_decl:
2464   case Intrinsic::var_annotation:
2465   case Intrinsic::sideeffect:
2466     // Discard annotate attributes, assumptions, and artificial side-effects.
2467     return true;
2468   case Intrinsic::read_volatile_register:
2469   case Intrinsic::read_register: {
2470     Value *Arg = CI.getArgOperand(0);
2471     MIRBuilder
2472         .buildInstr(TargetOpcode::G_READ_REGISTER, {getOrCreateVReg(CI)}, {})
2473         .addMetadata(cast<MDNode>(cast<MetadataAsValue>(Arg)->getMetadata()));
2474     return true;
2475   }
2476   case Intrinsic::write_register: {
2477     Value *Arg = CI.getArgOperand(0);
2478     MIRBuilder.buildInstr(TargetOpcode::G_WRITE_REGISTER)
2479       .addMetadata(cast<MDNode>(cast<MetadataAsValue>(Arg)->getMetadata()))
2480       .addUse(getOrCreateVReg(*CI.getArgOperand(1)));
2481     return true;
2482   }
2483   case Intrinsic::localescape: {
2484     MachineBasicBlock &EntryMBB = MF->front();
2485     StringRef EscapedName = GlobalValue::dropLLVMManglingEscape(MF->getName());
2486 
2487     // Directly emit some LOCAL_ESCAPE machine instrs. Label assignment emission
2488     // is the same on all targets.
2489     for (unsigned Idx = 0, E = CI.arg_size(); Idx < E; ++Idx) {
2490       Value *Arg = CI.getArgOperand(Idx)->stripPointerCasts();
2491       if (isa<ConstantPointerNull>(Arg))
2492         continue; // Skip null pointers. They represent a hole in index space.
2493 
2494       int FI = getOrCreateFrameIndex(*cast<AllocaInst>(Arg));
2495       MCSymbol *FrameAllocSym =
2496           MF->getContext().getOrCreateFrameAllocSymbol(EscapedName, Idx);
2497 
2498       // This should be inserted at the start of the entry block.
2499       auto LocalEscape =
2500           MIRBuilder.buildInstrNoInsert(TargetOpcode::LOCAL_ESCAPE)
2501               .addSym(FrameAllocSym)
2502               .addFrameIndex(FI);
2503 
2504       EntryMBB.insert(EntryMBB.begin(), LocalEscape);
2505     }
2506 
2507     return true;
2508   }
2509   case Intrinsic::vector_reduce_fadd:
2510   case Intrinsic::vector_reduce_fmul: {
2511     // Need to check for the reassoc flag to decide whether we want a
2512     // sequential reduction opcode or not.
2513     Register Dst = getOrCreateVReg(CI);
2514     Register ScalarSrc = getOrCreateVReg(*CI.getArgOperand(0));
2515     Register VecSrc = getOrCreateVReg(*CI.getArgOperand(1));
2516     unsigned Opc = 0;
2517     if (!CI.hasAllowReassoc()) {
2518       // The sequential ordering case.
2519       Opc = ID == Intrinsic::vector_reduce_fadd
2520                 ? TargetOpcode::G_VECREDUCE_SEQ_FADD
2521                 : TargetOpcode::G_VECREDUCE_SEQ_FMUL;
2522       MIRBuilder.buildInstr(Opc, {Dst}, {ScalarSrc, VecSrc},
2523                             MachineInstr::copyFlagsFromInstruction(CI));
2524       return true;
2525     }
2526     // We split the operation into a separate G_FADD/G_FMUL + the reduce,
2527     // since the associativity doesn't matter.
2528     unsigned ScalarOpc;
2529     if (ID == Intrinsic::vector_reduce_fadd) {
2530       Opc = TargetOpcode::G_VECREDUCE_FADD;
2531       ScalarOpc = TargetOpcode::G_FADD;
2532     } else {
2533       Opc = TargetOpcode::G_VECREDUCE_FMUL;
2534       ScalarOpc = TargetOpcode::G_FMUL;
2535     }
2536     LLT DstTy = MRI->getType(Dst);
2537     auto Rdx = MIRBuilder.buildInstr(
2538         Opc, {DstTy}, {VecSrc}, MachineInstr::copyFlagsFromInstruction(CI));
2539     MIRBuilder.buildInstr(ScalarOpc, {Dst}, {ScalarSrc, Rdx},
2540                           MachineInstr::copyFlagsFromInstruction(CI));
2541 
2542     return true;
2543   }
2544   case Intrinsic::trap:
2545     return translateTrap(CI, MIRBuilder, TargetOpcode::G_TRAP);
2546   case Intrinsic::debugtrap:
2547     return translateTrap(CI, MIRBuilder, TargetOpcode::G_DEBUGTRAP);
2548   case Intrinsic::ubsantrap:
2549     return translateTrap(CI, MIRBuilder, TargetOpcode::G_UBSANTRAP);
2550   case Intrinsic::allow_runtime_check:
2551   case Intrinsic::allow_ubsan_check:
2552     MIRBuilder.buildCopy(getOrCreateVReg(CI),
2553                          getOrCreateVReg(*ConstantInt::getTrue(CI.getType())));
2554     return true;
2555   case Intrinsic::amdgcn_cs_chain:
2556     return translateCallBase(CI, MIRBuilder);
2557   case Intrinsic::fptrunc_round: {
2558     uint32_t Flags = MachineInstr::copyFlagsFromInstruction(CI);
2559 
2560     // Convert the metadata argument to a constant integer
2561     Metadata *MD = cast<MetadataAsValue>(CI.getArgOperand(1))->getMetadata();
2562     std::optional<RoundingMode> RoundMode =
2563         convertStrToRoundingMode(cast<MDString>(MD)->getString());
2564 
2565     // Add the Rounding mode as an integer
2566     MIRBuilder
2567         .buildInstr(TargetOpcode::G_INTRINSIC_FPTRUNC_ROUND,
2568                     {getOrCreateVReg(CI)},
2569                     {getOrCreateVReg(*CI.getArgOperand(0))}, Flags)
2570         .addImm((int)*RoundMode);
2571 
2572     return true;
2573   }
2574   case Intrinsic::is_fpclass: {
2575     Value *FpValue = CI.getOperand(0);
2576     ConstantInt *TestMaskValue = cast<ConstantInt>(CI.getOperand(1));
2577 
2578     MIRBuilder
2579         .buildInstr(TargetOpcode::G_IS_FPCLASS, {getOrCreateVReg(CI)},
2580                     {getOrCreateVReg(*FpValue)})
2581         .addImm(TestMaskValue->getZExtValue());
2582 
2583     return true;
2584   }
2585   case Intrinsic::set_fpenv: {
2586     Value *FPEnv = CI.getOperand(0);
2587     MIRBuilder.buildSetFPEnv(getOrCreateVReg(*FPEnv));
2588     return true;
2589   }
2590   case Intrinsic::reset_fpenv:
2591     MIRBuilder.buildResetFPEnv();
2592     return true;
2593   case Intrinsic::set_fpmode: {
2594     Value *FPState = CI.getOperand(0);
2595     MIRBuilder.buildSetFPMode(getOrCreateVReg(*FPState));
2596     return true;
2597   }
2598   case Intrinsic::reset_fpmode:
2599     MIRBuilder.buildResetFPMode();
2600     return true;
2601   case Intrinsic::vscale: {
2602     MIRBuilder.buildVScale(getOrCreateVReg(CI), 1);
2603     return true;
2604   }
2605   case Intrinsic::scmp:
2606     MIRBuilder.buildSCmp(getOrCreateVReg(CI),
2607                          getOrCreateVReg(*CI.getOperand(0)),
2608                          getOrCreateVReg(*CI.getOperand(1)));
2609     return true;
2610   case Intrinsic::ucmp:
2611     MIRBuilder.buildUCmp(getOrCreateVReg(CI),
2612                          getOrCreateVReg(*CI.getOperand(0)),
2613                          getOrCreateVReg(*CI.getOperand(1)));
2614     return true;
2615   case Intrinsic::vector_extract:
2616     return translateExtractVector(CI, MIRBuilder);
2617   case Intrinsic::vector_insert:
2618     return translateInsertVector(CI, MIRBuilder);
2619   case Intrinsic::stepvector: {
2620     MIRBuilder.buildStepVector(getOrCreateVReg(CI), 1);
2621     return true;
2622   }
2623   case Intrinsic::prefetch: {
2624     Value *Addr = CI.getOperand(0);
2625     unsigned RW = cast<ConstantInt>(CI.getOperand(1))->getZExtValue();
2626     unsigned Locality = cast<ConstantInt>(CI.getOperand(2))->getZExtValue();
2627     unsigned CacheType = cast<ConstantInt>(CI.getOperand(3))->getZExtValue();
2628 
2629     auto Flags = RW ? MachineMemOperand::MOStore : MachineMemOperand::MOLoad;
2630     auto &MMO = *MF->getMachineMemOperand(MachinePointerInfo(Addr), Flags,
2631                                           LLT(), Align());
2632 
2633     MIRBuilder.buildPrefetch(getOrCreateVReg(*Addr), RW, Locality, CacheType,
2634                              MMO);
2635 
2636     return true;
2637   }
2638 
2639   case Intrinsic::vector_interleave2:
2640   case Intrinsic::vector_deinterleave2: {
2641     // Both intrinsics have at least one operand.
2642     Value *Op0 = CI.getOperand(0);
2643     LLT ResTy = getLLTForType(*Op0->getType(), MIRBuilder.getDataLayout());
2644     if (!ResTy.isFixedVector())
2645       return false;
2646 
2647     if (CI.getIntrinsicID() == Intrinsic::vector_interleave2)
2648       return translateVectorInterleave2Intrinsic(CI, MIRBuilder);
2649 
2650     return translateVectorDeinterleave2Intrinsic(CI, MIRBuilder);
2651   }
2652 
2653 #define INSTRUCTION(NAME, NARG, ROUND_MODE, INTRINSIC)  \
2654   case Intrinsic::INTRINSIC:
2655 #include "llvm/IR/ConstrainedOps.def"
2656     return translateConstrainedFPIntrinsic(cast<ConstrainedFPIntrinsic>(CI),
2657                                            MIRBuilder);
2658   case Intrinsic::experimental_convergence_anchor:
2659   case Intrinsic::experimental_convergence_entry:
2660   case Intrinsic::experimental_convergence_loop:
2661     return translateConvergenceControlIntrinsic(CI, ID, MIRBuilder);
2662   }
2663   return false;
2664 }
2665 
2666 bool IRTranslator::translateInlineAsm(const CallBase &CB,
2667                                       MachineIRBuilder &MIRBuilder) {
2668   if (containsBF16Type(CB))
2669     return false;
2670 
2671   const InlineAsmLowering *ALI = MF->getSubtarget().getInlineAsmLowering();
2672 
2673   if (!ALI) {
2674     LLVM_DEBUG(
2675         dbgs() << "Inline asm lowering is not supported for this target yet\n");
2676     return false;
2677   }
2678 
2679   return ALI->lowerInlineAsm(
2680       MIRBuilder, CB, [&](const Value &Val) { return getOrCreateVRegs(Val); });
2681 }
2682 
2683 bool IRTranslator::translateCallBase(const CallBase &CB,
2684                                      MachineIRBuilder &MIRBuilder) {
2685   ArrayRef<Register> Res = getOrCreateVRegs(CB);
2686 
2687   SmallVector<ArrayRef<Register>, 8> Args;
2688   Register SwiftInVReg = 0;
2689   Register SwiftErrorVReg = 0;
2690   for (const auto &Arg : CB.args()) {
2691     if (CLI->supportSwiftError() && isSwiftError(Arg)) {
2692       assert(SwiftInVReg == 0 && "Expected only one swift error argument");
2693       LLT Ty = getLLTForType(*Arg->getType(), *DL);
2694       SwiftInVReg = MRI->createGenericVirtualRegister(Ty);
2695       MIRBuilder.buildCopy(SwiftInVReg, SwiftError.getOrCreateVRegUseAt(
2696                                             &CB, &MIRBuilder.getMBB(), Arg));
2697       Args.emplace_back(ArrayRef(SwiftInVReg));
2698       SwiftErrorVReg =
2699           SwiftError.getOrCreateVRegDefAt(&CB, &MIRBuilder.getMBB(), Arg);
2700       continue;
2701     }
2702     Args.push_back(getOrCreateVRegs(*Arg));
2703   }
2704 
2705   if (auto *CI = dyn_cast<CallInst>(&CB)) {
2706     if (ORE->enabled()) {
2707       if (MemoryOpRemark::canHandle(CI, *LibInfo)) {
2708         MemoryOpRemark R(*ORE, "gisel-irtranslator-memsize", *DL, *LibInfo);
2709         R.visit(CI);
2710       }
2711     }
2712   }
2713 
2714   std::optional<CallLowering::PtrAuthInfo> PAI;
2715   if (auto Bundle = CB.getOperandBundle(LLVMContext::OB_ptrauth)) {
2716     // Functions should never be ptrauth-called directly.
2717     assert(!CB.getCalledFunction() && "invalid direct ptrauth call");
2718 
2719     const Value *Key = Bundle->Inputs[0];
2720     const Value *Discriminator = Bundle->Inputs[1];
2721 
2722     // Look through ptrauth constants to try to eliminate the matching bundle
2723     // and turn this into a direct call with no ptrauth.
2724     // CallLowering will use the raw pointer if it doesn't find the PAI.
2725     const auto *CalleeCPA = dyn_cast<ConstantPtrAuth>(CB.getCalledOperand());
2726     if (!CalleeCPA || !isa<Function>(CalleeCPA->getPointer()) ||
2727         !CalleeCPA->isKnownCompatibleWith(Key, Discriminator, *DL)) {
2728       // If we can't make it direct, package the bundle into PAI.
2729       Register DiscReg = getOrCreateVReg(*Discriminator);
2730       PAI = CallLowering::PtrAuthInfo{cast<ConstantInt>(Key)->getZExtValue(),
2731                                       DiscReg};
2732     }
2733   }
2734 
2735   Register ConvergenceCtrlToken = 0;
2736   if (auto Bundle = CB.getOperandBundle(LLVMContext::OB_convergencectrl)) {
2737     const auto &Token = *Bundle->Inputs[0].get();
2738     ConvergenceCtrlToken = getOrCreateConvergenceTokenVReg(Token);
2739   }
2740 
2741   // We don't set HasCalls on MFI here yet because call lowering may decide to
2742   // optimize into tail calls. Instead, we defer that to selection where a final
2743   // scan is done to check if any instructions are calls.
2744   bool Success = CLI->lowerCall(
2745       MIRBuilder, CB, Res, Args, SwiftErrorVReg, PAI, ConvergenceCtrlToken,
2746       [&]() { return getOrCreateVReg(*CB.getCalledOperand()); });
2747 
2748   // Check if we just inserted a tail call.
2749   if (Success) {
2750     assert(!HasTailCall && "Can't tail call return twice from block?");
2751     const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
2752     HasTailCall = TII->isTailCall(*std::prev(MIRBuilder.getInsertPt()));
2753   }
2754 
2755   return Success;
2756 }
2757 
2758 bool IRTranslator::translateCall(const User &U, MachineIRBuilder &MIRBuilder) {
2759   if (containsBF16Type(U))
2760     return false;
2761 
2762   const CallInst &CI = cast<CallInst>(U);
2763   auto TII = MF->getTarget().getIntrinsicInfo();
2764   const Function *F = CI.getCalledFunction();
2765 
2766   // FIXME: support Windows dllimport function calls and calls through
2767   // weak symbols.
2768   if (F && (F->hasDLLImportStorageClass() ||
2769             (MF->getTarget().getTargetTriple().isOSWindows() &&
2770              F->hasExternalWeakLinkage())))
2771     return false;
2772 
2773   // FIXME: support control flow guard targets.
2774   if (CI.countOperandBundlesOfType(LLVMContext::OB_cfguardtarget))
2775     return false;
2776 
2777   // FIXME: support statepoints and related.
2778   if (isa<GCStatepointInst, GCRelocateInst, GCResultInst>(U))
2779     return false;
2780 
2781   if (CI.isInlineAsm())
2782     return translateInlineAsm(CI, MIRBuilder);
2783 
2784   diagnoseDontCall(CI);
2785 
2786   Intrinsic::ID ID = Intrinsic::not_intrinsic;
2787   if (F && F->isIntrinsic()) {
2788     ID = F->getIntrinsicID();
2789     if (TII && ID == Intrinsic::not_intrinsic)
2790       ID = static_cast<Intrinsic::ID>(TII->getIntrinsicID(F));
2791   }
2792 
2793   if (!F || !F->isIntrinsic() || ID == Intrinsic::not_intrinsic)
2794     return translateCallBase(CI, MIRBuilder);
2795 
2796   assert(ID != Intrinsic::not_intrinsic && "unknown intrinsic");
2797 
2798   if (translateKnownIntrinsic(CI, ID, MIRBuilder))
2799     return true;
2800 
2801   ArrayRef<Register> ResultRegs;
2802   if (!CI.getType()->isVoidTy())
2803     ResultRegs = getOrCreateVRegs(CI);
2804 
2805   // Ignore the callsite attributes. Backend code is most likely not expecting
2806   // an intrinsic to sometimes have side effects and sometimes not.
2807   MachineInstrBuilder MIB = MIRBuilder.buildIntrinsic(ID, ResultRegs);
2808   if (isa<FPMathOperator>(CI))
2809     MIB->copyIRFlags(CI);
2810 
2811   for (const auto &Arg : enumerate(CI.args())) {
2812     // If this is required to be an immediate, don't materialize it in a
2813     // register.
2814     if (CI.paramHasAttr(Arg.index(), Attribute::ImmArg)) {
2815       if (ConstantInt *CI = dyn_cast<ConstantInt>(Arg.value())) {
2816         // imm arguments are more convenient than cimm (and realistically
2817         // probably sufficient), so use them.
2818         assert(CI->getBitWidth() <= 64 &&
2819                "large intrinsic immediates not handled");
2820         MIB.addImm(CI->getSExtValue());
2821       } else {
2822         MIB.addFPImm(cast<ConstantFP>(Arg.value()));
2823       }
2824     } else if (auto *MDVal = dyn_cast<MetadataAsValue>(Arg.value())) {
2825       auto *MD = MDVal->getMetadata();
2826       auto *MDN = dyn_cast<MDNode>(MD);
2827       if (!MDN) {
2828         if (auto *ConstMD = dyn_cast<ConstantAsMetadata>(MD))
2829           MDN = MDNode::get(MF->getFunction().getContext(), ConstMD);
2830         else // This was probably an MDString.
2831           return false;
2832       }
2833       MIB.addMetadata(MDN);
2834     } else {
2835       ArrayRef<Register> VRegs = getOrCreateVRegs(*Arg.value());
2836       if (VRegs.size() > 1)
2837         return false;
2838       MIB.addUse(VRegs[0]);
2839     }
2840   }
2841 
2842   // Add a MachineMemOperand if it is a target mem intrinsic.
2843   TargetLowering::IntrinsicInfo Info;
2844   // TODO: Add a GlobalISel version of getTgtMemIntrinsic.
2845   if (TLI->getTgtMemIntrinsic(Info, CI, *MF, ID)) {
2846     Align Alignment = Info.align.value_or(
2847         DL->getABITypeAlign(Info.memVT.getTypeForEVT(F->getContext())));
2848     LLT MemTy = Info.memVT.isSimple()
2849                     ? getLLTForMVT(Info.memVT.getSimpleVT())
2850                     : LLT::scalar(Info.memVT.getStoreSizeInBits());
2851 
2852     // TODO: We currently just fallback to address space 0 if getTgtMemIntrinsic
2853     //       didn't yield anything useful.
2854     MachinePointerInfo MPI;
2855     if (Info.ptrVal)
2856       MPI = MachinePointerInfo(Info.ptrVal, Info.offset);
2857     else if (Info.fallbackAddressSpace)
2858       MPI = MachinePointerInfo(*Info.fallbackAddressSpace);
2859     MIB.addMemOperand(
2860         MF->getMachineMemOperand(MPI, Info.flags, MemTy, Alignment, CI.getAAMetadata()));
2861   }
2862 
2863   if (CI.isConvergent()) {
2864     if (auto Bundle = CI.getOperandBundle(LLVMContext::OB_convergencectrl)) {
2865       auto *Token = Bundle->Inputs[0].get();
2866       Register TokenReg = getOrCreateVReg(*Token);
2867       MIB.addUse(TokenReg, RegState::Implicit);
2868     }
2869   }
2870 
2871   return true;
2872 }
2873 
2874 bool IRTranslator::findUnwindDestinations(
2875     const BasicBlock *EHPadBB,
2876     BranchProbability Prob,
2877     SmallVectorImpl<std::pair<MachineBasicBlock *, BranchProbability>>
2878         &UnwindDests) {
2879   EHPersonality Personality = classifyEHPersonality(
2880       EHPadBB->getParent()->getFunction().getPersonalityFn());
2881   bool IsMSVCCXX = Personality == EHPersonality::MSVC_CXX;
2882   bool IsCoreCLR = Personality == EHPersonality::CoreCLR;
2883   bool IsWasmCXX = Personality == EHPersonality::Wasm_CXX;
2884   bool IsSEH = isAsynchronousEHPersonality(Personality);
2885 
2886   if (IsWasmCXX) {
2887     // Ignore this for now.
2888     return false;
2889   }
2890 
2891   while (EHPadBB) {
2892     BasicBlock::const_iterator Pad = EHPadBB->getFirstNonPHIIt();
2893     BasicBlock *NewEHPadBB = nullptr;
2894     if (isa<LandingPadInst>(Pad)) {
2895       // Stop on landingpads. They are not funclets.
2896       UnwindDests.emplace_back(&getMBB(*EHPadBB), Prob);
2897       break;
2898     }
2899     if (isa<CleanupPadInst>(Pad)) {
2900       // Stop on cleanup pads. Cleanups are always funclet entries for all known
2901       // personalities.
2902       UnwindDests.emplace_back(&getMBB(*EHPadBB), Prob);
2903       UnwindDests.back().first->setIsEHScopeEntry();
2904       UnwindDests.back().first->setIsEHFuncletEntry();
2905       break;
2906     }
2907     if (auto *CatchSwitch = dyn_cast<CatchSwitchInst>(Pad)) {
2908       // Add the catchpad handlers to the possible destinations.
2909       for (const BasicBlock *CatchPadBB : CatchSwitch->handlers()) {
2910         UnwindDests.emplace_back(&getMBB(*CatchPadBB), Prob);
2911         // For MSVC++ and the CLR, catchblocks are funclets and need prologues.
2912         if (IsMSVCCXX || IsCoreCLR)
2913           UnwindDests.back().first->setIsEHFuncletEntry();
2914         if (!IsSEH)
2915           UnwindDests.back().first->setIsEHScopeEntry();
2916       }
2917       NewEHPadBB = CatchSwitch->getUnwindDest();
2918     } else {
2919       continue;
2920     }
2921 
2922     BranchProbabilityInfo *BPI = FuncInfo.BPI;
2923     if (BPI && NewEHPadBB)
2924       Prob *= BPI->getEdgeProbability(EHPadBB, NewEHPadBB);
2925     EHPadBB = NewEHPadBB;
2926   }
2927   return true;
2928 }
2929 
2930 bool IRTranslator::translateInvoke(const User &U,
2931                                    MachineIRBuilder &MIRBuilder) {
2932   const InvokeInst &I = cast<InvokeInst>(U);
2933   MCContext &Context = MF->getContext();
2934 
2935   const BasicBlock *ReturnBB = I.getSuccessor(0);
2936   const BasicBlock *EHPadBB = I.getSuccessor(1);
2937 
2938   const Function *Fn = I.getCalledFunction();
2939 
2940   // FIXME: support invoking patchpoint and statepoint intrinsics.
2941   if (Fn && Fn->isIntrinsic())
2942     return false;
2943 
2944   // FIXME: support whatever these are.
2945   if (I.hasDeoptState())
2946     return false;
2947 
2948   // FIXME: support control flow guard targets.
2949   if (I.countOperandBundlesOfType(LLVMContext::OB_cfguardtarget))
2950     return false;
2951 
2952   // FIXME: support Windows exception handling.
2953   if (!isa<LandingPadInst>(EHPadBB->getFirstNonPHIIt()))
2954     return false;
2955 
2956   // FIXME: support Windows dllimport function calls and calls through
2957   // weak symbols.
2958   if (Fn && (Fn->hasDLLImportStorageClass() ||
2959             (MF->getTarget().getTargetTriple().isOSWindows() &&
2960              Fn->hasExternalWeakLinkage())))
2961     return false;
2962 
2963   bool LowerInlineAsm = I.isInlineAsm();
2964   bool NeedEHLabel = true;
2965 
2966   // Emit the actual call, bracketed by EH_LABELs so that the MF knows about
2967   // the region covered by the try.
2968   MCSymbol *BeginSymbol = nullptr;
2969   if (NeedEHLabel) {
2970     MIRBuilder.buildInstr(TargetOpcode::G_INVOKE_REGION_START);
2971     BeginSymbol = Context.createTempSymbol();
2972     MIRBuilder.buildInstr(TargetOpcode::EH_LABEL).addSym(BeginSymbol);
2973   }
2974 
2975   if (LowerInlineAsm) {
2976     if (!translateInlineAsm(I, MIRBuilder))
2977       return false;
2978   } else if (!translateCallBase(I, MIRBuilder))
2979     return false;
2980 
2981   MCSymbol *EndSymbol = nullptr;
2982   if (NeedEHLabel) {
2983     EndSymbol = Context.createTempSymbol();
2984     MIRBuilder.buildInstr(TargetOpcode::EH_LABEL).addSym(EndSymbol);
2985   }
2986 
2987   SmallVector<std::pair<MachineBasicBlock *, BranchProbability>, 1> UnwindDests;
2988   BranchProbabilityInfo *BPI = FuncInfo.BPI;
2989   MachineBasicBlock *InvokeMBB = &MIRBuilder.getMBB();
2990   BranchProbability EHPadBBProb =
2991       BPI ? BPI->getEdgeProbability(InvokeMBB->getBasicBlock(), EHPadBB)
2992           : BranchProbability::getZero();
2993 
2994   if (!findUnwindDestinations(EHPadBB, EHPadBBProb, UnwindDests))
2995     return false;
2996 
2997   MachineBasicBlock &EHPadMBB = getMBB(*EHPadBB),
2998                     &ReturnMBB = getMBB(*ReturnBB);
2999   // Update successor info.
3000   addSuccessorWithProb(InvokeMBB, &ReturnMBB);
3001   for (auto &UnwindDest : UnwindDests) {
3002     UnwindDest.first->setIsEHPad();
3003     addSuccessorWithProb(InvokeMBB, UnwindDest.first, UnwindDest.second);
3004   }
3005   InvokeMBB->normalizeSuccProbs();
3006 
3007   if (NeedEHLabel) {
3008     assert(BeginSymbol && "Expected a begin symbol!");
3009     assert(EndSymbol && "Expected an end symbol!");
3010     MF->addInvoke(&EHPadMBB, BeginSymbol, EndSymbol);
3011   }
3012 
3013   MIRBuilder.buildBr(ReturnMBB);
3014   return true;
3015 }
3016 
3017 bool IRTranslator::translateCallBr(const User &U,
3018                                    MachineIRBuilder &MIRBuilder) {
3019   // FIXME: Implement this.
3020   return false;
3021 }
3022 
3023 bool IRTranslator::translateLandingPad(const User &U,
3024                                        MachineIRBuilder &MIRBuilder) {
3025   const LandingPadInst &LP = cast<LandingPadInst>(U);
3026 
3027   MachineBasicBlock &MBB = MIRBuilder.getMBB();
3028 
3029   MBB.setIsEHPad();
3030 
3031   // If there aren't registers to copy the values into (e.g., during SjLj
3032   // exceptions), then don't bother.
3033   const Constant *PersonalityFn = MF->getFunction().getPersonalityFn();
3034   if (TLI->getExceptionPointerRegister(PersonalityFn) == 0 &&
3035       TLI->getExceptionSelectorRegister(PersonalityFn) == 0)
3036     return true;
3037 
3038   // If landingpad's return type is token type, we don't create DAG nodes
3039   // for its exception pointer and selector value. The extraction of exception
3040   // pointer or selector value from token type landingpads is not currently
3041   // supported.
3042   if (LP.getType()->isTokenTy())
3043     return true;
3044 
3045   // Add a label to mark the beginning of the landing pad.  Deletion of the
3046   // landing pad can thus be detected via the MachineModuleInfo.
3047   MIRBuilder.buildInstr(TargetOpcode::EH_LABEL)
3048     .addSym(MF->addLandingPad(&MBB));
3049 
3050   // If the unwinder does not preserve all registers, ensure that the
3051   // function marks the clobbered registers as used.
3052   const TargetRegisterInfo &TRI = *MF->getSubtarget().getRegisterInfo();
3053   if (auto *RegMask = TRI.getCustomEHPadPreservedMask(*MF))
3054     MF->getRegInfo().addPhysRegsUsedFromRegMask(RegMask);
3055 
3056   LLT Ty = getLLTForType(*LP.getType(), *DL);
3057   Register Undef = MRI->createGenericVirtualRegister(Ty);
3058   MIRBuilder.buildUndef(Undef);
3059 
3060   SmallVector<LLT, 2> Tys;
3061   for (Type *Ty : cast<StructType>(LP.getType())->elements())
3062     Tys.push_back(getLLTForType(*Ty, *DL));
3063   assert(Tys.size() == 2 && "Only two-valued landingpads are supported");
3064 
3065   // Mark exception register as live in.
3066   Register ExceptionReg = TLI->getExceptionPointerRegister(PersonalityFn);
3067   if (!ExceptionReg)
3068     return false;
3069 
3070   MBB.addLiveIn(ExceptionReg);
3071   ArrayRef<Register> ResRegs = getOrCreateVRegs(LP);
3072   MIRBuilder.buildCopy(ResRegs[0], ExceptionReg);
3073 
3074   Register SelectorReg = TLI->getExceptionSelectorRegister(PersonalityFn);
3075   if (!SelectorReg)
3076     return false;
3077 
3078   MBB.addLiveIn(SelectorReg);
3079   Register PtrVReg = MRI->createGenericVirtualRegister(Tys[0]);
3080   MIRBuilder.buildCopy(PtrVReg, SelectorReg);
3081   MIRBuilder.buildCast(ResRegs[1], PtrVReg);
3082 
3083   return true;
3084 }
3085 
3086 bool IRTranslator::translateAlloca(const User &U,
3087                                    MachineIRBuilder &MIRBuilder) {
3088   auto &AI = cast<AllocaInst>(U);
3089 
3090   if (AI.isSwiftError())
3091     return true;
3092 
3093   if (AI.isStaticAlloca()) {
3094     Register Res = getOrCreateVReg(AI);
3095     int FI = getOrCreateFrameIndex(AI);
3096     MIRBuilder.buildFrameIndex(Res, FI);
3097     return true;
3098   }
3099 
3100   // FIXME: support stack probing for Windows.
3101   if (MF->getTarget().getTargetTriple().isOSWindows())
3102     return false;
3103 
3104   // Now we're in the harder dynamic case.
3105   Register NumElts = getOrCreateVReg(*AI.getArraySize());
3106   Type *IntPtrIRTy = DL->getIntPtrType(AI.getType());
3107   LLT IntPtrTy = getLLTForType(*IntPtrIRTy, *DL);
3108   if (MRI->getType(NumElts) != IntPtrTy) {
3109     Register ExtElts = MRI->createGenericVirtualRegister(IntPtrTy);
3110     MIRBuilder.buildZExtOrTrunc(ExtElts, NumElts);
3111     NumElts = ExtElts;
3112   }
3113 
3114   Type *Ty = AI.getAllocatedType();
3115 
3116   Register AllocSize = MRI->createGenericVirtualRegister(IntPtrTy);
3117   Register TySize =
3118       getOrCreateVReg(*ConstantInt::get(IntPtrIRTy, DL->getTypeAllocSize(Ty)));
3119   MIRBuilder.buildMul(AllocSize, NumElts, TySize);
3120 
3121   // Round the size of the allocation up to the stack alignment size
3122   // by add SA-1 to the size. This doesn't overflow because we're computing
3123   // an address inside an alloca.
3124   Align StackAlign = MF->getSubtarget().getFrameLowering()->getStackAlign();
3125   auto SAMinusOne = MIRBuilder.buildConstant(IntPtrTy, StackAlign.value() - 1);
3126   auto AllocAdd = MIRBuilder.buildAdd(IntPtrTy, AllocSize, SAMinusOne,
3127                                       MachineInstr::NoUWrap);
3128   auto AlignCst =
3129       MIRBuilder.buildConstant(IntPtrTy, ~(uint64_t)(StackAlign.value() - 1));
3130   auto AlignedAlloc = MIRBuilder.buildAnd(IntPtrTy, AllocAdd, AlignCst);
3131 
3132   Align Alignment = std::max(AI.getAlign(), DL->getPrefTypeAlign(Ty));
3133   if (Alignment <= StackAlign)
3134     Alignment = Align(1);
3135   MIRBuilder.buildDynStackAlloc(getOrCreateVReg(AI), AlignedAlloc, Alignment);
3136 
3137   MF->getFrameInfo().CreateVariableSizedObject(Alignment, &AI);
3138   assert(MF->getFrameInfo().hasVarSizedObjects());
3139   return true;
3140 }
3141 
3142 bool IRTranslator::translateVAArg(const User &U, MachineIRBuilder &MIRBuilder) {
3143   // FIXME: We may need more info about the type. Because of how LLT works,
3144   // we're completely discarding the i64/double distinction here (amongst
3145   // others). Fortunately the ABIs I know of where that matters don't use va_arg
3146   // anyway but that's not guaranteed.
3147   MIRBuilder.buildInstr(TargetOpcode::G_VAARG, {getOrCreateVReg(U)},
3148                         {getOrCreateVReg(*U.getOperand(0)),
3149                          DL->getABITypeAlign(U.getType()).value()});
3150   return true;
3151 }
3152 
3153 bool IRTranslator::translateUnreachable(const User &U, MachineIRBuilder &MIRBuilder) {
3154   if (!MF->getTarget().Options.TrapUnreachable)
3155     return true;
3156 
3157   auto &UI = cast<UnreachableInst>(U);
3158 
3159   // We may be able to ignore unreachable behind a noreturn call.
3160   if (const CallInst *Call = dyn_cast_or_null<CallInst>(UI.getPrevNode());
3161       Call && Call->doesNotReturn()) {
3162     if (MF->getTarget().Options.NoTrapAfterNoreturn)
3163       return true;
3164     // Do not emit an additional trap instruction.
3165     if (Call->isNonContinuableTrap())
3166       return true;
3167   }
3168 
3169   MIRBuilder.buildTrap();
3170   return true;
3171 }
3172 
3173 bool IRTranslator::translateInsertElement(const User &U,
3174                                           MachineIRBuilder &MIRBuilder) {
3175   // If it is a <1 x Ty> vector, use the scalar as it is
3176   // not a legal vector type in LLT.
3177   if (auto *FVT = dyn_cast<FixedVectorType>(U.getType());
3178       FVT && FVT->getNumElements() == 1)
3179     return translateCopy(U, *U.getOperand(1), MIRBuilder);
3180 
3181   Register Res = getOrCreateVReg(U);
3182   Register Val = getOrCreateVReg(*U.getOperand(0));
3183   Register Elt = getOrCreateVReg(*U.getOperand(1));
3184   unsigned PreferredVecIdxWidth = TLI->getVectorIdxTy(*DL).getSizeInBits();
3185   Register Idx;
3186   if (auto *CI = dyn_cast<ConstantInt>(U.getOperand(2))) {
3187     if (CI->getBitWidth() != PreferredVecIdxWidth) {
3188       APInt NewIdx = CI->getValue().zextOrTrunc(PreferredVecIdxWidth);
3189       auto *NewIdxCI = ConstantInt::get(CI->getContext(), NewIdx);
3190       Idx = getOrCreateVReg(*NewIdxCI);
3191     }
3192   }
3193   if (!Idx)
3194     Idx = getOrCreateVReg(*U.getOperand(2));
3195   if (MRI->getType(Idx).getSizeInBits() != PreferredVecIdxWidth) {
3196     const LLT VecIdxTy = LLT::scalar(PreferredVecIdxWidth);
3197     Idx = MIRBuilder.buildZExtOrTrunc(VecIdxTy, Idx).getReg(0);
3198   }
3199   MIRBuilder.buildInsertVectorElement(Res, Val, Elt, Idx);
3200   return true;
3201 }
3202 
3203 bool IRTranslator::translateInsertVector(const User &U,
3204                                          MachineIRBuilder &MIRBuilder) {
3205   Register Dst = getOrCreateVReg(U);
3206   Register Vec = getOrCreateVReg(*U.getOperand(0));
3207   Register Elt = getOrCreateVReg(*U.getOperand(1));
3208 
3209   ConstantInt *CI = cast<ConstantInt>(U.getOperand(2));
3210   unsigned PreferredVecIdxWidth = TLI->getVectorIdxTy(*DL).getSizeInBits();
3211 
3212   // Resize Index to preferred index width.
3213   if (CI->getBitWidth() != PreferredVecIdxWidth) {
3214     APInt NewIdx = CI->getValue().zextOrTrunc(PreferredVecIdxWidth);
3215     CI = ConstantInt::get(CI->getContext(), NewIdx);
3216   }
3217 
3218   // If it is a <1 x Ty> vector, we have to use other means.
3219   if (auto *ResultType = dyn_cast<FixedVectorType>(U.getOperand(1)->getType());
3220       ResultType && ResultType->getNumElements() == 1) {
3221     if (auto *InputType = dyn_cast<FixedVectorType>(U.getOperand(0)->getType());
3222         InputType && InputType->getNumElements() == 1) {
3223       // We are inserting an illegal fixed vector into an illegal
3224       // fixed vector, use the scalar as it is not a legal vector type
3225       // in LLT.
3226       return translateCopy(U, *U.getOperand(0), MIRBuilder);
3227     }
3228     if (isa<FixedVectorType>(U.getOperand(0)->getType())) {
3229       // We are inserting an illegal fixed vector into a legal fixed
3230       // vector, use the scalar as it is not a legal vector type in
3231       // LLT.
3232       Register Idx = getOrCreateVReg(*CI);
3233       MIRBuilder.buildInsertVectorElement(Dst, Vec, Elt, Idx);
3234       return true;
3235     }
3236     if (isa<ScalableVectorType>(U.getOperand(0)->getType())) {
3237       // We are inserting an illegal fixed vector into a scalable
3238       // vector, use a scalar element insert.
3239       LLT VecIdxTy = LLT::scalar(PreferredVecIdxWidth);
3240       Register Idx = getOrCreateVReg(*CI);
3241       auto ScaledIndex = MIRBuilder.buildMul(
3242           VecIdxTy, MIRBuilder.buildVScale(VecIdxTy, 1), Idx);
3243       MIRBuilder.buildInsertVectorElement(Dst, Vec, Elt, ScaledIndex);
3244       return true;
3245     }
3246   }
3247 
3248   MIRBuilder.buildInsertSubvector(
3249       getOrCreateVReg(U), getOrCreateVReg(*U.getOperand(0)),
3250       getOrCreateVReg(*U.getOperand(1)), CI->getZExtValue());
3251   return true;
3252 }
3253 
3254 bool IRTranslator::translateExtractElement(const User &U,
3255                                            MachineIRBuilder &MIRBuilder) {
3256   // If it is a <1 x Ty> vector, use the scalar as it is
3257   // not a legal vector type in LLT.
3258   if (const FixedVectorType *FVT =
3259           dyn_cast<FixedVectorType>(U.getOperand(0)->getType()))
3260     if (FVT->getNumElements() == 1)
3261       return translateCopy(U, *U.getOperand(0), MIRBuilder);
3262 
3263   Register Res = getOrCreateVReg(U);
3264   Register Val = getOrCreateVReg(*U.getOperand(0));
3265   unsigned PreferredVecIdxWidth = TLI->getVectorIdxTy(*DL).getSizeInBits();
3266   Register Idx;
3267   if (auto *CI = dyn_cast<ConstantInt>(U.getOperand(1))) {
3268     if (CI->getBitWidth() != PreferredVecIdxWidth) {
3269       APInt NewIdx = CI->getValue().zextOrTrunc(PreferredVecIdxWidth);
3270       auto *NewIdxCI = ConstantInt::get(CI->getContext(), NewIdx);
3271       Idx = getOrCreateVReg(*NewIdxCI);
3272     }
3273   }
3274   if (!Idx)
3275     Idx = getOrCreateVReg(*U.getOperand(1));
3276   if (MRI->getType(Idx).getSizeInBits() != PreferredVecIdxWidth) {
3277     const LLT VecIdxTy = LLT::scalar(PreferredVecIdxWidth);
3278     Idx = MIRBuilder.buildZExtOrTrunc(VecIdxTy, Idx).getReg(0);
3279   }
3280   MIRBuilder.buildExtractVectorElement(Res, Val, Idx);
3281   return true;
3282 }
3283 
3284 bool IRTranslator::translateExtractVector(const User &U,
3285                                           MachineIRBuilder &MIRBuilder) {
3286   Register Res = getOrCreateVReg(U);
3287   Register Vec = getOrCreateVReg(*U.getOperand(0));
3288   ConstantInt *CI = cast<ConstantInt>(U.getOperand(1));
3289   unsigned PreferredVecIdxWidth = TLI->getVectorIdxTy(*DL).getSizeInBits();
3290 
3291   // Resize Index to preferred index width.
3292   if (CI->getBitWidth() != PreferredVecIdxWidth) {
3293     APInt NewIdx = CI->getValue().zextOrTrunc(PreferredVecIdxWidth);
3294     CI = ConstantInt::get(CI->getContext(), NewIdx);
3295   }
3296 
3297   // If it is a <1 x Ty> vector, we have to use other means.
3298   if (auto *ResultType = dyn_cast<FixedVectorType>(U.getType());
3299       ResultType && ResultType->getNumElements() == 1) {
3300     if (auto *InputType = dyn_cast<FixedVectorType>(U.getOperand(0)->getType());
3301         InputType && InputType->getNumElements() == 1) {
3302       // We are extracting an illegal fixed vector from an illegal fixed vector,
3303       // use the scalar as it is not a legal vector type in LLT.
3304       return translateCopy(U, *U.getOperand(0), MIRBuilder);
3305     }
3306     if (isa<FixedVectorType>(U.getOperand(0)->getType())) {
3307       // We are extracting an illegal fixed vector from a legal fixed
3308       // vector, use the scalar as it is not a legal vector type in
3309       // LLT.
3310       Register Idx = getOrCreateVReg(*CI);
3311       MIRBuilder.buildExtractVectorElement(Res, Vec, Idx);
3312       return true;
3313     }
3314     if (isa<ScalableVectorType>(U.getOperand(0)->getType())) {
3315       // We are extracting an illegal fixed vector from a scalable
3316       // vector, use a scalar element extract.
3317       LLT VecIdxTy = LLT::scalar(PreferredVecIdxWidth);
3318       Register Idx = getOrCreateVReg(*CI);
3319       auto ScaledIndex = MIRBuilder.buildMul(
3320           VecIdxTy, MIRBuilder.buildVScale(VecIdxTy, 1), Idx);
3321       MIRBuilder.buildExtractVectorElement(Res, Vec, ScaledIndex);
3322       return true;
3323     }
3324   }
3325 
3326   MIRBuilder.buildExtractSubvector(getOrCreateVReg(U),
3327                                    getOrCreateVReg(*U.getOperand(0)),
3328                                    CI->getZExtValue());
3329   return true;
3330 }
3331 
3332 bool IRTranslator::translateShuffleVector(const User &U,
3333                                           MachineIRBuilder &MIRBuilder) {
3334   // A ShuffleVector that operates on scalable vectors is a splat vector where
3335   // the value of the splat vector is the 0th element of the first operand,
3336   // since the index mask operand is the zeroinitializer (undef and
3337   // poison are treated as zeroinitializer here).
3338   if (U.getOperand(0)->getType()->isScalableTy()) {
3339     Register Val = getOrCreateVReg(*U.getOperand(0));
3340     auto SplatVal = MIRBuilder.buildExtractVectorElementConstant(
3341         MRI->getType(Val).getElementType(), Val, 0);
3342     MIRBuilder.buildSplatVector(getOrCreateVReg(U), SplatVal);
3343     return true;
3344   }
3345 
3346   ArrayRef<int> Mask;
3347   if (auto *SVI = dyn_cast<ShuffleVectorInst>(&U))
3348     Mask = SVI->getShuffleMask();
3349   else
3350     Mask = cast<ConstantExpr>(U).getShuffleMask();
3351   ArrayRef<int> MaskAlloc = MF->allocateShuffleMask(Mask);
3352   MIRBuilder
3353       .buildInstr(TargetOpcode::G_SHUFFLE_VECTOR, {getOrCreateVReg(U)},
3354                   {getOrCreateVReg(*U.getOperand(0)),
3355                    getOrCreateVReg(*U.getOperand(1))})
3356       .addShuffleMask(MaskAlloc);
3357   return true;
3358 }
3359 
3360 bool IRTranslator::translatePHI(const User &U, MachineIRBuilder &MIRBuilder) {
3361   const PHINode &PI = cast<PHINode>(U);
3362 
3363   SmallVector<MachineInstr *, 4> Insts;
3364   for (auto Reg : getOrCreateVRegs(PI)) {
3365     auto MIB = MIRBuilder.buildInstr(TargetOpcode::G_PHI, {Reg}, {});
3366     Insts.push_back(MIB.getInstr());
3367   }
3368 
3369   PendingPHIs.emplace_back(&PI, std::move(Insts));
3370   return true;
3371 }
3372 
3373 bool IRTranslator::translateAtomicCmpXchg(const User &U,
3374                                           MachineIRBuilder &MIRBuilder) {
3375   const AtomicCmpXchgInst &I = cast<AtomicCmpXchgInst>(U);
3376 
3377   auto Flags = TLI->getAtomicMemOperandFlags(I, *DL);
3378 
3379   auto Res = getOrCreateVRegs(I);
3380   Register OldValRes = Res[0];
3381   Register SuccessRes = Res[1];
3382   Register Addr = getOrCreateVReg(*I.getPointerOperand());
3383   Register Cmp = getOrCreateVReg(*I.getCompareOperand());
3384   Register NewVal = getOrCreateVReg(*I.getNewValOperand());
3385 
3386   MIRBuilder.buildAtomicCmpXchgWithSuccess(
3387       OldValRes, SuccessRes, Addr, Cmp, NewVal,
3388       *MF->getMachineMemOperand(
3389           MachinePointerInfo(I.getPointerOperand()), Flags, MRI->getType(Cmp),
3390           getMemOpAlign(I), I.getAAMetadata(), nullptr, I.getSyncScopeID(),
3391           I.getSuccessOrdering(), I.getFailureOrdering()));
3392   return true;
3393 }
3394 
3395 bool IRTranslator::translateAtomicRMW(const User &U,
3396                                       MachineIRBuilder &MIRBuilder) {
3397   if (containsBF16Type(U))
3398     return false;
3399 
3400   const AtomicRMWInst &I = cast<AtomicRMWInst>(U);
3401   auto Flags = TLI->getAtomicMemOperandFlags(I, *DL);
3402 
3403   Register Res = getOrCreateVReg(I);
3404   Register Addr = getOrCreateVReg(*I.getPointerOperand());
3405   Register Val = getOrCreateVReg(*I.getValOperand());
3406 
3407   unsigned Opcode = 0;
3408   switch (I.getOperation()) {
3409   default:
3410     return false;
3411   case AtomicRMWInst::Xchg:
3412     Opcode = TargetOpcode::G_ATOMICRMW_XCHG;
3413     break;
3414   case AtomicRMWInst::Add:
3415     Opcode = TargetOpcode::G_ATOMICRMW_ADD;
3416     break;
3417   case AtomicRMWInst::Sub:
3418     Opcode = TargetOpcode::G_ATOMICRMW_SUB;
3419     break;
3420   case AtomicRMWInst::And:
3421     Opcode = TargetOpcode::G_ATOMICRMW_AND;
3422     break;
3423   case AtomicRMWInst::Nand:
3424     Opcode = TargetOpcode::G_ATOMICRMW_NAND;
3425     break;
3426   case AtomicRMWInst::Or:
3427     Opcode = TargetOpcode::G_ATOMICRMW_OR;
3428     break;
3429   case AtomicRMWInst::Xor:
3430     Opcode = TargetOpcode::G_ATOMICRMW_XOR;
3431     break;
3432   case AtomicRMWInst::Max:
3433     Opcode = TargetOpcode::G_ATOMICRMW_MAX;
3434     break;
3435   case AtomicRMWInst::Min:
3436     Opcode = TargetOpcode::G_ATOMICRMW_MIN;
3437     break;
3438   case AtomicRMWInst::UMax:
3439     Opcode = TargetOpcode::G_ATOMICRMW_UMAX;
3440     break;
3441   case AtomicRMWInst::UMin:
3442     Opcode = TargetOpcode::G_ATOMICRMW_UMIN;
3443     break;
3444   case AtomicRMWInst::FAdd:
3445     Opcode = TargetOpcode::G_ATOMICRMW_FADD;
3446     break;
3447   case AtomicRMWInst::FSub:
3448     Opcode = TargetOpcode::G_ATOMICRMW_FSUB;
3449     break;
3450   case AtomicRMWInst::FMax:
3451     Opcode = TargetOpcode::G_ATOMICRMW_FMAX;
3452     break;
3453   case AtomicRMWInst::FMin:
3454     Opcode = TargetOpcode::G_ATOMICRMW_FMIN;
3455     break;
3456   case AtomicRMWInst::UIncWrap:
3457     Opcode = TargetOpcode::G_ATOMICRMW_UINC_WRAP;
3458     break;
3459   case AtomicRMWInst::UDecWrap:
3460     Opcode = TargetOpcode::G_ATOMICRMW_UDEC_WRAP;
3461     break;
3462   case AtomicRMWInst::USubCond:
3463     Opcode = TargetOpcode::G_ATOMICRMW_USUB_COND;
3464     break;
3465   case AtomicRMWInst::USubSat:
3466     Opcode = TargetOpcode::G_ATOMICRMW_USUB_SAT;
3467     break;
3468   }
3469 
3470   MIRBuilder.buildAtomicRMW(
3471       Opcode, Res, Addr, Val,
3472       *MF->getMachineMemOperand(MachinePointerInfo(I.getPointerOperand()),
3473                                 Flags, MRI->getType(Val), getMemOpAlign(I),
3474                                 I.getAAMetadata(), nullptr, I.getSyncScopeID(),
3475                                 I.getOrdering()));
3476   return true;
3477 }
3478 
3479 bool IRTranslator::translateFence(const User &U,
3480                                   MachineIRBuilder &MIRBuilder) {
3481   const FenceInst &Fence = cast<FenceInst>(U);
3482   MIRBuilder.buildFence(static_cast<unsigned>(Fence.getOrdering()),
3483                         Fence.getSyncScopeID());
3484   return true;
3485 }
3486 
3487 bool IRTranslator::translateFreeze(const User &U,
3488                                    MachineIRBuilder &MIRBuilder) {
3489   const ArrayRef<Register> DstRegs = getOrCreateVRegs(U);
3490   const ArrayRef<Register> SrcRegs = getOrCreateVRegs(*U.getOperand(0));
3491 
3492   assert(DstRegs.size() == SrcRegs.size() &&
3493          "Freeze with different source and destination type?");
3494 
3495   for (unsigned I = 0; I < DstRegs.size(); ++I) {
3496     MIRBuilder.buildFreeze(DstRegs[I], SrcRegs[I]);
3497   }
3498 
3499   return true;
3500 }
3501 
3502 void IRTranslator::finishPendingPhis() {
3503 #ifndef NDEBUG
3504   DILocationVerifier Verifier;
3505   GISelObserverWrapper WrapperObserver(&Verifier);
3506   RAIIMFObsDelInstaller ObsInstall(*MF, WrapperObserver);
3507 #endif // ifndef NDEBUG
3508   for (auto &Phi : PendingPHIs) {
3509     const PHINode *PI = Phi.first;
3510     if (PI->getType()->isEmptyTy())
3511       continue;
3512     ArrayRef<MachineInstr *> ComponentPHIs = Phi.second;
3513     MachineBasicBlock *PhiMBB = ComponentPHIs[0]->getParent();
3514     EntryBuilder->setDebugLoc(PI->getDebugLoc());
3515 #ifndef NDEBUG
3516     Verifier.setCurrentInst(PI);
3517 #endif // ifndef NDEBUG
3518 
3519     SmallSet<const MachineBasicBlock *, 16> SeenPreds;
3520     for (unsigned i = 0; i < PI->getNumIncomingValues(); ++i) {
3521       auto IRPred = PI->getIncomingBlock(i);
3522       ArrayRef<Register> ValRegs = getOrCreateVRegs(*PI->getIncomingValue(i));
3523       for (auto *Pred : getMachinePredBBs({IRPred, PI->getParent()})) {
3524         if (SeenPreds.count(Pred) || !PhiMBB->isPredecessor(Pred))
3525           continue;
3526         SeenPreds.insert(Pred);
3527         for (unsigned j = 0; j < ValRegs.size(); ++j) {
3528           MachineInstrBuilder MIB(*MF, ComponentPHIs[j]);
3529           MIB.addUse(ValRegs[j]);
3530           MIB.addMBB(Pred);
3531         }
3532       }
3533     }
3534   }
3535 }
3536 
3537 void IRTranslator::translateDbgValueRecord(Value *V, bool HasArgList,
3538                                      const DILocalVariable *Variable,
3539                                      const DIExpression *Expression,
3540                                      const DebugLoc &DL,
3541                                      MachineIRBuilder &MIRBuilder) {
3542   assert(Variable->isValidLocationForIntrinsic(DL) &&
3543          "Expected inlined-at fields to agree");
3544   // Act as if we're handling a debug intrinsic.
3545   MIRBuilder.setDebugLoc(DL);
3546 
3547   if (!V || HasArgList) {
3548     // DI cannot produce a valid DBG_VALUE, so produce an undef DBG_VALUE to
3549     // terminate any prior location.
3550     MIRBuilder.buildIndirectDbgValue(0, Variable, Expression);
3551     return;
3552   }
3553 
3554   if (const auto *CI = dyn_cast<Constant>(V)) {
3555     MIRBuilder.buildConstDbgValue(*CI, Variable, Expression);
3556     return;
3557   }
3558 
3559   if (auto *AI = dyn_cast<AllocaInst>(V);
3560       AI && AI->isStaticAlloca() && Expression->startsWithDeref()) {
3561     // If the value is an alloca and the expression starts with a
3562     // dereference, track a stack slot instead of a register, as registers
3563     // may be clobbered.
3564     auto ExprOperands = Expression->getElements();
3565     auto *ExprDerefRemoved =
3566         DIExpression::get(AI->getContext(), ExprOperands.drop_front());
3567     MIRBuilder.buildFIDbgValue(getOrCreateFrameIndex(*AI), Variable,
3568                                ExprDerefRemoved);
3569     return;
3570   }
3571   if (translateIfEntryValueArgument(false, V, Variable, Expression, DL,
3572                                     MIRBuilder))
3573     return;
3574   for (Register Reg : getOrCreateVRegs(*V)) {
3575     // FIXME: This does not handle register-indirect values at offset 0. The
3576     // direct/indirect thing shouldn't really be handled by something as
3577     // implicit as reg+noreg vs reg+imm in the first place, but it seems
3578     // pretty baked in right now.
3579     MIRBuilder.buildDirectDbgValue(Reg, Variable, Expression);
3580   }
3581 }
3582 
3583 void IRTranslator::translateDbgDeclareRecord(Value *Address, bool HasArgList,
3584                                      const DILocalVariable *Variable,
3585                                      const DIExpression *Expression,
3586                                      const DebugLoc &DL,
3587                                      MachineIRBuilder &MIRBuilder) {
3588   if (!Address || isa<UndefValue>(Address)) {
3589     LLVM_DEBUG(dbgs() << "Dropping debug info for " << *Variable << "\n");
3590     return;
3591   }
3592 
3593   assert(Variable->isValidLocationForIntrinsic(DL) &&
3594          "Expected inlined-at fields to agree");
3595   auto AI = dyn_cast<AllocaInst>(Address);
3596   if (AI && AI->isStaticAlloca()) {
3597     // Static allocas are tracked at the MF level, no need for DBG_VALUE
3598     // instructions (in fact, they get ignored if they *do* exist).
3599     MF->setVariableDbgInfo(Variable, Expression,
3600                            getOrCreateFrameIndex(*AI), DL);
3601     return;
3602   }
3603 
3604   if (translateIfEntryValueArgument(true, Address, Variable,
3605                                     Expression, DL,
3606                                     MIRBuilder))
3607     return;
3608 
3609   // A dbg.declare describes the address of a source variable, so lower it
3610   // into an indirect DBG_VALUE.
3611   MIRBuilder.setDebugLoc(DL);
3612   MIRBuilder.buildIndirectDbgValue(getOrCreateVReg(*Address),
3613                                    Variable, Expression);
3614   return;
3615 }
3616 
3617 void IRTranslator::translateDbgInfo(const Instruction &Inst,
3618                                       MachineIRBuilder &MIRBuilder) {
3619   for (DbgRecord &DR : Inst.getDbgRecordRange()) {
3620     if (DbgLabelRecord *DLR = dyn_cast<DbgLabelRecord>(&DR)) {
3621       MIRBuilder.setDebugLoc(DLR->getDebugLoc());
3622       assert(DLR->getLabel() && "Missing label");
3623       assert(DLR->getLabel()->isValidLocationForIntrinsic(
3624                  MIRBuilder.getDebugLoc()) &&
3625              "Expected inlined-at fields to agree");
3626       MIRBuilder.buildDbgLabel(DLR->getLabel());
3627       continue;
3628     }
3629     DbgVariableRecord &DVR = cast<DbgVariableRecord>(DR);
3630     const DILocalVariable *Variable = DVR.getVariable();
3631     const DIExpression *Expression = DVR.getExpression();
3632     Value *V = DVR.getVariableLocationOp(0);
3633     if (DVR.isDbgDeclare())
3634       translateDbgDeclareRecord(V, DVR.hasArgList(), Variable, Expression,
3635                                 DVR.getDebugLoc(), MIRBuilder);
3636     else
3637       translateDbgValueRecord(V, DVR.hasArgList(), Variable, Expression,
3638                               DVR.getDebugLoc(), MIRBuilder);
3639   }
3640 }
3641 
3642 bool IRTranslator::translate(const Instruction &Inst) {
3643   CurBuilder->setDebugLoc(Inst.getDebugLoc());
3644   CurBuilder->setPCSections(Inst.getMetadata(LLVMContext::MD_pcsections));
3645   CurBuilder->setMMRAMetadata(Inst.getMetadata(LLVMContext::MD_mmra));
3646 
3647   if (TLI->fallBackToDAGISel(Inst))
3648     return false;
3649 
3650   switch (Inst.getOpcode()) {
3651 #define HANDLE_INST(NUM, OPCODE, CLASS)                                        \
3652   case Instruction::OPCODE:                                                    \
3653     return translate##OPCODE(Inst, *CurBuilder.get());
3654 #include "llvm/IR/Instruction.def"
3655   default:
3656     return false;
3657   }
3658 }
3659 
3660 bool IRTranslator::translate(const Constant &C, Register Reg) {
3661   // We only emit constants into the entry block from here. To prevent jumpy
3662   // debug behaviour remove debug line.
3663   if (auto CurrInstDL = CurBuilder->getDL())
3664     EntryBuilder->setDebugLoc(DebugLoc());
3665 
3666   if (auto CI = dyn_cast<ConstantInt>(&C))
3667     EntryBuilder->buildConstant(Reg, *CI);
3668   else if (auto CF = dyn_cast<ConstantFP>(&C))
3669     EntryBuilder->buildFConstant(Reg, *CF);
3670   else if (isa<UndefValue>(C))
3671     EntryBuilder->buildUndef(Reg);
3672   else if (isa<ConstantPointerNull>(C))
3673     EntryBuilder->buildConstant(Reg, 0);
3674   else if (auto GV = dyn_cast<GlobalValue>(&C))
3675     EntryBuilder->buildGlobalValue(Reg, GV);
3676   else if (auto CPA = dyn_cast<ConstantPtrAuth>(&C)) {
3677     Register Addr = getOrCreateVReg(*CPA->getPointer());
3678     Register AddrDisc = getOrCreateVReg(*CPA->getAddrDiscriminator());
3679     EntryBuilder->buildConstantPtrAuth(Reg, CPA, Addr, AddrDisc);
3680   } else if (auto CAZ = dyn_cast<ConstantAggregateZero>(&C)) {
3681     Constant &Elt = *CAZ->getElementValue(0u);
3682     if (isa<ScalableVectorType>(CAZ->getType())) {
3683       EntryBuilder->buildSplatVector(Reg, getOrCreateVReg(Elt));
3684       return true;
3685     }
3686     // Return the scalar if it is a <1 x Ty> vector.
3687     unsigned NumElts = CAZ->getElementCount().getFixedValue();
3688     if (NumElts == 1)
3689       return translateCopy(C, Elt, *EntryBuilder);
3690     // All elements are zero so we can just use the first one.
3691     EntryBuilder->buildSplatBuildVector(Reg, getOrCreateVReg(Elt));
3692   } else if (auto CV = dyn_cast<ConstantDataVector>(&C)) {
3693     // Return the scalar if it is a <1 x Ty> vector.
3694     if (CV->getNumElements() == 1)
3695       return translateCopy(C, *CV->getElementAsConstant(0), *EntryBuilder);
3696     SmallVector<Register, 4> Ops;
3697     for (unsigned i = 0; i < CV->getNumElements(); ++i) {
3698       Constant &Elt = *CV->getElementAsConstant(i);
3699       Ops.push_back(getOrCreateVReg(Elt));
3700     }
3701     EntryBuilder->buildBuildVector(Reg, Ops);
3702   } else if (auto CE = dyn_cast<ConstantExpr>(&C)) {
3703     switch(CE->getOpcode()) {
3704 #define HANDLE_INST(NUM, OPCODE, CLASS)                                        \
3705   case Instruction::OPCODE:                                                    \
3706     return translate##OPCODE(*CE, *EntryBuilder.get());
3707 #include "llvm/IR/Instruction.def"
3708     default:
3709       return false;
3710     }
3711   } else if (auto CV = dyn_cast<ConstantVector>(&C)) {
3712     if (CV->getNumOperands() == 1)
3713       return translateCopy(C, *CV->getOperand(0), *EntryBuilder);
3714     SmallVector<Register, 4> Ops;
3715     for (unsigned i = 0; i < CV->getNumOperands(); ++i) {
3716       Ops.push_back(getOrCreateVReg(*CV->getOperand(i)));
3717     }
3718     EntryBuilder->buildBuildVector(Reg, Ops);
3719   } else if (auto *BA = dyn_cast<BlockAddress>(&C)) {
3720     EntryBuilder->buildBlockAddress(Reg, BA);
3721   } else
3722     return false;
3723 
3724   return true;
3725 }
3726 
3727 bool IRTranslator::finalizeBasicBlock(const BasicBlock &BB,
3728                                       MachineBasicBlock &MBB) {
3729   for (auto &BTB : SL->BitTestCases) {
3730     // Emit header first, if it wasn't already emitted.
3731     if (!BTB.Emitted)
3732       emitBitTestHeader(BTB, BTB.Parent);
3733 
3734     BranchProbability UnhandledProb = BTB.Prob;
3735     for (unsigned j = 0, ej = BTB.Cases.size(); j != ej; ++j) {
3736       UnhandledProb -= BTB.Cases[j].ExtraProb;
3737       // Set the current basic block to the mbb we wish to insert the code into
3738       MachineBasicBlock *MBB = BTB.Cases[j].ThisBB;
3739       // If all cases cover a contiguous range, it is not necessary to jump to
3740       // the default block after the last bit test fails. This is because the
3741       // range check during bit test header creation has guaranteed that every
3742       // case here doesn't go outside the range. In this case, there is no need
3743       // to perform the last bit test, as it will always be true. Instead, make
3744       // the second-to-last bit-test fall through to the target of the last bit
3745       // test, and delete the last bit test.
3746 
3747       MachineBasicBlock *NextMBB;
3748       if ((BTB.ContiguousRange || BTB.FallthroughUnreachable) && j + 2 == ej) {
3749         // Second-to-last bit-test with contiguous range: fall through to the
3750         // target of the final bit test.
3751         NextMBB = BTB.Cases[j + 1].TargetBB;
3752       } else if (j + 1 == ej) {
3753         // For the last bit test, fall through to Default.
3754         NextMBB = BTB.Default;
3755       } else {
3756         // Otherwise, fall through to the next bit test.
3757         NextMBB = BTB.Cases[j + 1].ThisBB;
3758       }
3759 
3760       emitBitTestCase(BTB, NextMBB, UnhandledProb, BTB.Reg, BTB.Cases[j], MBB);
3761 
3762       if ((BTB.ContiguousRange || BTB.FallthroughUnreachable) && j + 2 == ej) {
3763         // We need to record the replacement phi edge here that normally
3764         // happens in emitBitTestCase before we delete the case, otherwise the
3765         // phi edge will be lost.
3766         addMachineCFGPred({BTB.Parent->getBasicBlock(),
3767                            BTB.Cases[ej - 1].TargetBB->getBasicBlock()},
3768                           MBB);
3769         // Since we're not going to use the final bit test, remove it.
3770         BTB.Cases.pop_back();
3771         break;
3772       }
3773     }
3774     // This is "default" BB. We have two jumps to it. From "header" BB and from
3775     // last "case" BB, unless the latter was skipped.
3776     CFGEdge HeaderToDefaultEdge = {BTB.Parent->getBasicBlock(),
3777                                    BTB.Default->getBasicBlock()};
3778     addMachineCFGPred(HeaderToDefaultEdge, BTB.Parent);
3779     if (!BTB.ContiguousRange) {
3780       addMachineCFGPred(HeaderToDefaultEdge, BTB.Cases.back().ThisBB);
3781     }
3782   }
3783   SL->BitTestCases.clear();
3784 
3785   for (auto &JTCase : SL->JTCases) {
3786     // Emit header first, if it wasn't already emitted.
3787     if (!JTCase.first.Emitted)
3788       emitJumpTableHeader(JTCase.second, JTCase.first, JTCase.first.HeaderBB);
3789 
3790     emitJumpTable(JTCase.second, JTCase.second.MBB);
3791   }
3792   SL->JTCases.clear();
3793 
3794   for (auto &SwCase : SL->SwitchCases)
3795     emitSwitchCase(SwCase, &CurBuilder->getMBB(), *CurBuilder);
3796   SL->SwitchCases.clear();
3797 
3798   // Check if we need to generate stack-protector guard checks.
3799   StackProtector &SP = getAnalysis<StackProtector>();
3800   if (SP.shouldEmitSDCheck(BB)) {
3801     bool FunctionBasedInstrumentation =
3802         TLI->getSSPStackGuardCheck(*MF->getFunction().getParent());
3803     SPDescriptor.initialize(&BB, &MBB, FunctionBasedInstrumentation);
3804   }
3805   // Handle stack protector.
3806   if (SPDescriptor.shouldEmitFunctionBasedCheckStackProtector()) {
3807     LLVM_DEBUG(dbgs() << "Unimplemented stack protector case\n");
3808     return false;
3809   } else if (SPDescriptor.shouldEmitStackProtector()) {
3810     MachineBasicBlock *ParentMBB = SPDescriptor.getParentMBB();
3811     MachineBasicBlock *SuccessMBB = SPDescriptor.getSuccessMBB();
3812 
3813     // Find the split point to split the parent mbb. At the same time copy all
3814     // physical registers used in the tail of parent mbb into virtual registers
3815     // before the split point and back into physical registers after the split
3816     // point. This prevents us needing to deal with Live-ins and many other
3817     // register allocation issues caused by us splitting the parent mbb. The
3818     // register allocator will clean up said virtual copies later on.
3819     MachineBasicBlock::iterator SplitPoint = findSplitPointForStackProtector(
3820         ParentMBB, *MF->getSubtarget().getInstrInfo());
3821 
3822     // Splice the terminator of ParentMBB into SuccessMBB.
3823     SuccessMBB->splice(SuccessMBB->end(), ParentMBB, SplitPoint,
3824                        ParentMBB->end());
3825 
3826     // Add compare/jump on neq/jump to the parent BB.
3827     if (!emitSPDescriptorParent(SPDescriptor, ParentMBB))
3828       return false;
3829 
3830     // CodeGen Failure MBB if we have not codegened it yet.
3831     MachineBasicBlock *FailureMBB = SPDescriptor.getFailureMBB();
3832     if (FailureMBB->empty()) {
3833       if (!emitSPDescriptorFailure(SPDescriptor, FailureMBB))
3834         return false;
3835     }
3836 
3837     // Clear the Per-BB State.
3838     SPDescriptor.resetPerBBState();
3839   }
3840   return true;
3841 }
3842 
3843 bool IRTranslator::emitSPDescriptorParent(StackProtectorDescriptor &SPD,
3844                                           MachineBasicBlock *ParentBB) {
3845   CurBuilder->setInsertPt(*ParentBB, ParentBB->end());
3846   // First create the loads to the guard/stack slot for the comparison.
3847   Type *PtrIRTy = PointerType::getUnqual(MF->getFunction().getContext());
3848   const LLT PtrTy = getLLTForType(*PtrIRTy, *DL);
3849   LLT PtrMemTy = getLLTForMVT(TLI->getPointerMemTy(*DL));
3850 
3851   MachineFrameInfo &MFI = ParentBB->getParent()->getFrameInfo();
3852   int FI = MFI.getStackProtectorIndex();
3853 
3854   Register Guard;
3855   Register StackSlotPtr = CurBuilder->buildFrameIndex(PtrTy, FI).getReg(0);
3856   const Module &M = *ParentBB->getParent()->getFunction().getParent();
3857   Align Align = DL->getPrefTypeAlign(PointerType::getUnqual(M.getContext()));
3858 
3859   // Generate code to load the content of the guard slot.
3860   Register GuardVal =
3861       CurBuilder
3862           ->buildLoad(PtrMemTy, StackSlotPtr,
3863                       MachinePointerInfo::getFixedStack(*MF, FI), Align,
3864                       MachineMemOperand::MOLoad | MachineMemOperand::MOVolatile)
3865           .getReg(0);
3866 
3867   if (TLI->useStackGuardXorFP()) {
3868     LLVM_DEBUG(dbgs() << "Stack protector xor'ing with FP not yet implemented");
3869     return false;
3870   }
3871 
3872   // Retrieve guard check function, nullptr if instrumentation is inlined.
3873   if (const Function *GuardCheckFn = TLI->getSSPStackGuardCheck(M)) {
3874     // This path is currently untestable on GlobalISel, since the only platform
3875     // that needs this seems to be Windows, and we fall back on that currently.
3876     // The code still lives here in case that changes.
3877     // Silence warning about unused variable until the code below that uses
3878     // 'GuardCheckFn' is enabled.
3879     (void)GuardCheckFn;
3880     return false;
3881 #if 0
3882     // The target provides a guard check function to validate the guard value.
3883     // Generate a call to that function with the content of the guard slot as
3884     // argument.
3885     FunctionType *FnTy = GuardCheckFn->getFunctionType();
3886     assert(FnTy->getNumParams() == 1 && "Invalid function signature");
3887     ISD::ArgFlagsTy Flags;
3888     if (GuardCheckFn->hasAttribute(1, Attribute::AttrKind::InReg))
3889       Flags.setInReg();
3890     CallLowering::ArgInfo GuardArgInfo(
3891         {GuardVal, FnTy->getParamType(0), {Flags}});
3892 
3893     CallLowering::CallLoweringInfo Info;
3894     Info.OrigArgs.push_back(GuardArgInfo);
3895     Info.CallConv = GuardCheckFn->getCallingConv();
3896     Info.Callee = MachineOperand::CreateGA(GuardCheckFn, 0);
3897     Info.OrigRet = {Register(), FnTy->getReturnType()};
3898     if (!CLI->lowerCall(MIRBuilder, Info)) {
3899       LLVM_DEBUG(dbgs() << "Failed to lower call to stack protector check\n");
3900       return false;
3901     }
3902     return true;
3903 #endif
3904   }
3905 
3906   // If useLoadStackGuardNode returns true, generate LOAD_STACK_GUARD.
3907   // Otherwise, emit a volatile load to retrieve the stack guard value.
3908   if (TLI->useLoadStackGuardNode(*ParentBB->getBasicBlock()->getModule())) {
3909     Guard =
3910         MRI->createGenericVirtualRegister(LLT::scalar(PtrTy.getSizeInBits()));
3911     getStackGuard(Guard, *CurBuilder);
3912   } else {
3913     // TODO: test using android subtarget when we support @llvm.thread.pointer.
3914     const Value *IRGuard = TLI->getSDagStackGuard(M);
3915     Register GuardPtr = getOrCreateVReg(*IRGuard);
3916 
3917     Guard = CurBuilder
3918                 ->buildLoad(PtrMemTy, GuardPtr,
3919                             MachinePointerInfo::getFixedStack(*MF, FI), Align,
3920                             MachineMemOperand::MOLoad |
3921                                 MachineMemOperand::MOVolatile)
3922                 .getReg(0);
3923   }
3924 
3925   // Perform the comparison.
3926   auto Cmp =
3927       CurBuilder->buildICmp(CmpInst::ICMP_NE, LLT::scalar(1), Guard, GuardVal);
3928   // If the guard/stackslot do not equal, branch to failure MBB.
3929   CurBuilder->buildBrCond(Cmp, *SPD.getFailureMBB());
3930   // Otherwise branch to success MBB.
3931   CurBuilder->buildBr(*SPD.getSuccessMBB());
3932   return true;
3933 }
3934 
3935 bool IRTranslator::emitSPDescriptorFailure(StackProtectorDescriptor &SPD,
3936                                            MachineBasicBlock *FailureBB) {
3937   CurBuilder->setInsertPt(*FailureBB, FailureBB->end());
3938 
3939   const RTLIB::Libcall Libcall = RTLIB::STACKPROTECTOR_CHECK_FAIL;
3940   const char *Name = TLI->getLibcallName(Libcall);
3941 
3942   CallLowering::CallLoweringInfo Info;
3943   Info.CallConv = TLI->getLibcallCallingConv(Libcall);
3944   Info.Callee = MachineOperand::CreateES(Name);
3945   Info.OrigRet = {Register(), Type::getVoidTy(MF->getFunction().getContext()),
3946                   0};
3947   if (!CLI->lowerCall(*CurBuilder, Info)) {
3948     LLVM_DEBUG(dbgs() << "Failed to lower call to stack protector fail\n");
3949     return false;
3950   }
3951 
3952   // Emit a trap instruction if we are required to do so.
3953   const TargetOptions &TargetOpts = TLI->getTargetMachine().Options;
3954   if (TargetOpts.TrapUnreachable && !TargetOpts.NoTrapAfterNoreturn)
3955     CurBuilder->buildInstr(TargetOpcode::G_TRAP);
3956 
3957   return true;
3958 }
3959 
3960 void IRTranslator::finalizeFunction() {
3961   // Release the memory used by the different maps we
3962   // needed during the translation.
3963   PendingPHIs.clear();
3964   VMap.reset();
3965   FrameIndices.clear();
3966   MachinePreds.clear();
3967   // MachineIRBuilder::DebugLoc can outlive the DILocation it holds. Clear it
3968   // to avoid accessing free’d memory (in runOnMachineFunction) and to avoid
3969   // destroying it twice (in ~IRTranslator() and ~LLVMContext())
3970   EntryBuilder.reset();
3971   CurBuilder.reset();
3972   FuncInfo.clear();
3973   SPDescriptor.resetPerFunctionState();
3974 }
3975 
3976 /// Returns true if a BasicBlock \p BB within a variadic function contains a
3977 /// variadic musttail call.
3978 static bool checkForMustTailInVarArgFn(bool IsVarArg, const BasicBlock &BB) {
3979   if (!IsVarArg)
3980     return false;
3981 
3982   // Walk the block backwards, because tail calls usually only appear at the end
3983   // of a block.
3984   return llvm::any_of(llvm::reverse(BB), [](const Instruction &I) {
3985     const auto *CI = dyn_cast<CallInst>(&I);
3986     return CI && CI->isMustTailCall();
3987   });
3988 }
3989 
3990 bool IRTranslator::runOnMachineFunction(MachineFunction &CurMF) {
3991   MF = &CurMF;
3992   const Function &F = MF->getFunction();
3993   GISelCSEAnalysisWrapper &Wrapper =
3994       getAnalysis<GISelCSEAnalysisWrapperPass>().getCSEWrapper();
3995   // Set the CSEConfig and run the analysis.
3996   GISelCSEInfo *CSEInfo = nullptr;
3997   TPC = &getAnalysis<TargetPassConfig>();
3998   bool EnableCSE = EnableCSEInIRTranslator.getNumOccurrences()
3999                        ? EnableCSEInIRTranslator
4000                        : TPC->isGISelCSEEnabled();
4001   TLI = MF->getSubtarget().getTargetLowering();
4002 
4003   if (EnableCSE) {
4004     EntryBuilder = std::make_unique<CSEMIRBuilder>(CurMF);
4005     CSEInfo = &Wrapper.get(TPC->getCSEConfig());
4006     EntryBuilder->setCSEInfo(CSEInfo);
4007     CurBuilder = std::make_unique<CSEMIRBuilder>(CurMF);
4008     CurBuilder->setCSEInfo(CSEInfo);
4009   } else {
4010     EntryBuilder = std::make_unique<MachineIRBuilder>();
4011     CurBuilder = std::make_unique<MachineIRBuilder>();
4012   }
4013   CLI = MF->getSubtarget().getCallLowering();
4014   CurBuilder->setMF(*MF);
4015   EntryBuilder->setMF(*MF);
4016   MRI = &MF->getRegInfo();
4017   DL = &F.getDataLayout();
4018   ORE = std::make_unique<OptimizationRemarkEmitter>(&F);
4019   const TargetMachine &TM = MF->getTarget();
4020   TM.resetTargetOptions(F);
4021   EnableOpts = OptLevel != CodeGenOptLevel::None && !skipFunction(F);
4022   FuncInfo.MF = MF;
4023   if (EnableOpts) {
4024     AA = &getAnalysis<AAResultsWrapperPass>().getAAResults();
4025     FuncInfo.BPI = &getAnalysis<BranchProbabilityInfoWrapperPass>().getBPI();
4026   } else {
4027     AA = nullptr;
4028     FuncInfo.BPI = nullptr;
4029   }
4030 
4031   AC = &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(
4032       MF->getFunction());
4033   LibInfo = &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI(F);
4034   FuncInfo.CanLowerReturn = CLI->checkReturnTypeForCallConv(*MF);
4035 
4036   SL = std::make_unique<GISelSwitchLowering>(this, FuncInfo);
4037   SL->init(*TLI, TM, *DL);
4038 
4039   assert(PendingPHIs.empty() && "stale PHIs");
4040 
4041   // Targets which want to use big endian can enable it using
4042   // enableBigEndian()
4043   if (!DL->isLittleEndian() && !CLI->enableBigEndian()) {
4044     // Currently we don't properly handle big endian code.
4045     OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
4046                                F.getSubprogram(), &F.getEntryBlock());
4047     R << "unable to translate in big endian mode";
4048     reportTranslationError(*MF, *TPC, *ORE, R);
4049     return false;
4050   }
4051 
4052   // Release the per-function state when we return, whether we succeeded or not.
4053   auto FinalizeOnReturn = make_scope_exit([this]() { finalizeFunction(); });
4054 
4055   // Setup a separate basic-block for the arguments and constants
4056   MachineBasicBlock *EntryBB = MF->CreateMachineBasicBlock();
4057   MF->push_back(EntryBB);
4058   EntryBuilder->setMBB(*EntryBB);
4059 
4060   DebugLoc DbgLoc = F.getEntryBlock().getFirstNonPHIIt()->getDebugLoc();
4061   SwiftError.setFunction(CurMF);
4062   SwiftError.createEntriesInEntryBlock(DbgLoc);
4063 
4064   bool IsVarArg = F.isVarArg();
4065   bool HasMustTailInVarArgFn = false;
4066 
4067   // Create all blocks, in IR order, to preserve the layout.
4068   FuncInfo.MBBMap.resize(F.getMaxBlockNumber());
4069   for (const BasicBlock &BB: F) {
4070     auto *&MBB = FuncInfo.MBBMap[BB.getNumber()];
4071 
4072     MBB = MF->CreateMachineBasicBlock(&BB);
4073     MF->push_back(MBB);
4074 
4075     if (BB.hasAddressTaken())
4076       MBB->setAddressTakenIRBlock(const_cast<BasicBlock *>(&BB));
4077 
4078     if (!HasMustTailInVarArgFn)
4079       HasMustTailInVarArgFn = checkForMustTailInVarArgFn(IsVarArg, BB);
4080   }
4081 
4082   MF->getFrameInfo().setHasMustTailInVarArgFunc(HasMustTailInVarArgFn);
4083 
4084   // Make our arguments/constants entry block fallthrough to the IR entry block.
4085   EntryBB->addSuccessor(&getMBB(F.front()));
4086 
4087   if (CLI->fallBackToDAGISel(*MF)) {
4088     OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
4089                                F.getSubprogram(), &F.getEntryBlock());
4090     R << "unable to lower function: "
4091       << ore::NV("Prototype", F.getFunctionType());
4092     reportTranslationError(*MF, *TPC, *ORE, R);
4093     return false;
4094   }
4095 
4096   // Lower the actual args into this basic block.
4097   SmallVector<ArrayRef<Register>, 8> VRegArgs;
4098   for (const Argument &Arg: F.args()) {
4099     if (DL->getTypeStoreSize(Arg.getType()).isZero())
4100       continue; // Don't handle zero sized types.
4101     ArrayRef<Register> VRegs = getOrCreateVRegs(Arg);
4102     VRegArgs.push_back(VRegs);
4103 
4104     if (Arg.hasSwiftErrorAttr()) {
4105       assert(VRegs.size() == 1 && "Too many vregs for Swift error");
4106       SwiftError.setCurrentVReg(EntryBB, SwiftError.getFunctionArg(), VRegs[0]);
4107     }
4108   }
4109 
4110   if (!CLI->lowerFormalArguments(*EntryBuilder, F, VRegArgs, FuncInfo)) {
4111     OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
4112                                F.getSubprogram(), &F.getEntryBlock());
4113     R << "unable to lower arguments: "
4114       << ore::NV("Prototype", F.getFunctionType());
4115     reportTranslationError(*MF, *TPC, *ORE, R);
4116     return false;
4117   }
4118 
4119   // Need to visit defs before uses when translating instructions.
4120   GISelObserverWrapper WrapperObserver;
4121   if (EnableCSE && CSEInfo)
4122     WrapperObserver.addObserver(CSEInfo);
4123   {
4124     ReversePostOrderTraversal<const Function *> RPOT(&F);
4125 #ifndef NDEBUG
4126     DILocationVerifier Verifier;
4127     WrapperObserver.addObserver(&Verifier);
4128 #endif // ifndef NDEBUG
4129     RAIIMFObsDelInstaller ObsInstall(*MF, WrapperObserver);
4130     for (const BasicBlock *BB : RPOT) {
4131       MachineBasicBlock &MBB = getMBB(*BB);
4132       // Set the insertion point of all the following translations to
4133       // the end of this basic block.
4134       CurBuilder->setMBB(MBB);
4135       HasTailCall = false;
4136       for (const Instruction &Inst : *BB) {
4137         // If we translated a tail call in the last step, then we know
4138         // everything after the call is either a return, or something that is
4139         // handled by the call itself. (E.g. a lifetime marker or assume
4140         // intrinsic.) In this case, we should stop translating the block and
4141         // move on.
4142         if (HasTailCall)
4143           break;
4144 #ifndef NDEBUG
4145         Verifier.setCurrentInst(&Inst);
4146 #endif // ifndef NDEBUG
4147 
4148         // Translate any debug-info attached to the instruction.
4149         translateDbgInfo(Inst, *CurBuilder);
4150 
4151         if (translate(Inst))
4152           continue;
4153 
4154         OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
4155                                    Inst.getDebugLoc(), BB);
4156         R << "unable to translate instruction: " << ore::NV("Opcode", &Inst);
4157 
4158         if (ORE->allowExtraAnalysis("gisel-irtranslator")) {
4159           std::string InstStrStorage;
4160           raw_string_ostream InstStr(InstStrStorage);
4161           InstStr << Inst;
4162 
4163           R << ": '" << InstStrStorage << "'";
4164         }
4165 
4166         reportTranslationError(*MF, *TPC, *ORE, R);
4167         return false;
4168       }
4169 
4170       if (!finalizeBasicBlock(*BB, MBB)) {
4171         OptimizationRemarkMissed R("gisel-irtranslator", "GISelFailure",
4172                                    BB->getTerminator()->getDebugLoc(), BB);
4173         R << "unable to translate basic block";
4174         reportTranslationError(*MF, *TPC, *ORE, R);
4175         return false;
4176       }
4177     }
4178 #ifndef NDEBUG
4179     WrapperObserver.removeObserver(&Verifier);
4180 #endif
4181   }
4182 
4183   finishPendingPhis();
4184 
4185   SwiftError.propagateVRegs();
4186 
4187   // Merge the argument lowering and constants block with its single
4188   // successor, the LLVM-IR entry block.  We want the basic block to
4189   // be maximal.
4190   assert(EntryBB->succ_size() == 1 &&
4191          "Custom BB used for lowering should have only one successor");
4192   // Get the successor of the current entry block.
4193   MachineBasicBlock &NewEntryBB = **EntryBB->succ_begin();
4194   assert(NewEntryBB.pred_size() == 1 &&
4195          "LLVM-IR entry block has a predecessor!?");
4196   // Move all the instruction from the current entry block to the
4197   // new entry block.
4198   NewEntryBB.splice(NewEntryBB.begin(), EntryBB, EntryBB->begin(),
4199                     EntryBB->end());
4200 
4201   // Update the live-in information for the new entry block.
4202   for (const MachineBasicBlock::RegisterMaskPair &LiveIn : EntryBB->liveins())
4203     NewEntryBB.addLiveIn(LiveIn);
4204   NewEntryBB.sortUniqueLiveIns();
4205 
4206   // Get rid of the now empty basic block.
4207   EntryBB->removeSuccessor(&NewEntryBB);
4208   MF->remove(EntryBB);
4209   MF->deleteMachineBasicBlock(EntryBB);
4210 
4211   assert(&MF->front() == &NewEntryBB &&
4212          "New entry wasn't next in the list of basic block!");
4213 
4214   // Initialize stack protector information.
4215   StackProtector &SP = getAnalysis<StackProtector>();
4216   SP.copyToMachineFrameInfo(MF->getFrameInfo());
4217 
4218   return false;
4219 }
4220