unittests/CodeGen/MachineInstrTest.cpp

   1 //===- MachineInstrTest.cpp -----------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "llvm/CodeGen/MachineBasicBlock.h"
  10 #include "llvm/CodeGen/MachineInstr.h"
  11 #include "llvm/CodeGen/MachineFunction.h"
  12 #include "llvm/CodeGen/MachineModuleInfo.h"
  13 #include "llvm/CodeGen/TargetFrameLowering.h"
  14 #include "llvm/CodeGen/TargetInstrInfo.h"
  15 #include "llvm/CodeGen/TargetLowering.h"
  16 #include "llvm/CodeGen/TargetSubtargetInfo.h"
  17 #include "llvm/IR/DebugInfoMetadata.h"
  18 #include "llvm/IR/ModuleSlotTracker.h"
  19 #include "llvm/Support/TargetRegistry.h"
  20 #include "llvm/Support/TargetSelect.h"
  21 #include "llvm/Target/TargetMachine.h"
  22 #include "llvm/Target/TargetOptions.h"
  23 #include "gtest/gtest.h"
  24
  25 using namespace llvm;
  26
  27 namespace {
  28 // Add a few Bogus backend classes so we can create MachineInstrs without
  29 // depending on a real target.
  30 class BogusTargetLowering : public TargetLowering {
  31 public:
  32   BogusTargetLowering(TargetMachine &TM) : TargetLowering(TM) {}
  33 };
  34
  35 class BogusFrameLowering : public TargetFrameLowering {
  36 public:
  37   BogusFrameLowering()
  38       : TargetFrameLowering(TargetFrameLowering::StackGrowsDown, 4, 4) {}
  39
  40   void emitPrologue(MachineFunction &MF,
  41                     MachineBasicBlock &MBB) const override {}
  42   void emitEpilogue(MachineFunction &MF,
  43                     MachineBasicBlock &MBB) const override {}
  44   bool hasFP(const MachineFunction &MF) const override { return false; }
  45 };
  46
  47 static TargetRegisterClass *const BogusRegisterClasses[] = {nullptr};
  48
  49 class BogusRegisterInfo : public TargetRegisterInfo {
  50 public:
  51   BogusRegisterInfo()
  52       : TargetRegisterInfo(nullptr, BogusRegisterClasses, BogusRegisterClasses,
  53                            nullptr, nullptr, LaneBitmask(~0u), nullptr) {
  54     InitMCRegisterInfo(nullptr, 0, 0, 0, nullptr, 0, nullptr, 0, nullptr,
  55                        nullptr, nullptr, nullptr, nullptr, 0, nullptr, nullptr);
  56   }
  57
  58   const MCPhysReg *
  59   getCalleeSavedRegs(const MachineFunction *MF) const override {
  60     return nullptr;
  61   }
  62   ArrayRef<const uint32_t *> getRegMasks() const override { return None; }
  63   ArrayRef<const char *> getRegMaskNames() const override { return None; }
  64   BitVector getReservedRegs(const MachineFunction &MF) const override {
  65     return BitVector();
  66   }
  67   const RegClassWeight &
  68   getRegClassWeight(const TargetRegisterClass *RC) const override {
  69     static RegClassWeight Bogus{1, 16};
  70     return Bogus;
  71   }
  72   unsigned getRegUnitWeight(unsigned RegUnit) const override { return 1; }
  73   unsigned getNumRegPressureSets() const override { return 0; }
  74   const char *getRegPressureSetName(unsigned Idx) const override {
  75     return "bogus";
  76   }
  77   unsigned getRegPressureSetLimit(const MachineFunction &MF,
  78                                   unsigned Idx) const override {
  79     return 0;
  80   }
  81   const int *
  82   getRegClassPressureSets(const TargetRegisterClass *RC) const override {
  83     static const int Bogus[] = {0, -1};
  84     return &Bogus[0];
  85   }
  86   const int *getRegUnitPressureSets(unsigned RegUnit) const override {
  87     static const int Bogus[] = {0, -1};
  88     return &Bogus[0];
  89   }
  90
  91   Register getFrameRegister(const MachineFunction &MF) const override {
  92     return 0;
  93   }
  94   void eliminateFrameIndex(MachineBasicBlock::iterator MI, int SPAdj,
  95                            unsigned FIOperandNum,
  96                            RegScavenger *RS = nullptr) const override {}
  97 };
  98
  99 class BogusSubtarget : public TargetSubtargetInfo {
 100 public:
 101   BogusSubtarget(TargetMachine &TM)
 102       : TargetSubtargetInfo(Triple(""), "", "", {}, {}, nullptr, nullptr,
 103                             nullptr, nullptr, nullptr, nullptr),
 104         FL(), TL(TM) {}
 105   ~BogusSubtarget() override {}
 106
 107   const TargetFrameLowering *getFrameLowering() const override { return &FL; }
 108
 109   const TargetLowering *getTargetLowering() const override { return &TL; }
 110
 111   const TargetInstrInfo *getInstrInfo() const override { return &TII; }
 112
 113   const TargetRegisterInfo *getRegisterInfo() const override { return &TRI; }
 114
 115 private:
 116   BogusFrameLowering FL;
 117   BogusRegisterInfo TRI;
 118   BogusTargetLowering TL;
 119   TargetInstrInfo TII;
 120 };
 121
 122 class BogusTargetMachine : public LLVMTargetMachine {
 123 public:
 124   BogusTargetMachine()
 125       : LLVMTargetMachine(Target(), "", Triple(""), "", "", TargetOptions(),
 126                           Reloc::Static, CodeModel::Small, CodeGenOpt::Default),
 127         ST(*this) {}
 128   ~BogusTargetMachine() override {}
 129
 130   const TargetSubtargetInfo *getSubtargetImpl(const Function &) const override {
 131     return &ST;
 132   }
 133
 134 private:
 135   BogusSubtarget ST;
 136 };
 137
 138 std::unique_ptr<BogusTargetMachine> createTargetMachine() {
 139   return std::make_unique<BogusTargetMachine>();
 140 }
 141
 142 std::unique_ptr<MachineFunction> createMachineFunction() {
 143   LLVMContext Ctx;
 144   Module M("Module", Ctx);
 145   auto Type = FunctionType::get(Type::getVoidTy(Ctx), false);
 146   auto F = Function::Create(Type, GlobalValue::ExternalLinkage, "Test", &M);
 147
 148   auto TM = createTargetMachine();
 149   unsigned FunctionNum = 42;
 150   MachineModuleInfo MMI(TM.get());
 151   const TargetSubtargetInfo &STI = *TM->getSubtargetImpl(*F);
 152
 153   return std::make_unique<MachineFunction>(*F, *TM, STI, FunctionNum, MMI);
 154 }
 155
 156 // This test makes sure that MachineInstr::isIdenticalTo handles Defs correctly
 157 // for various combinations of IgnoreDefs, and also that it is symmetrical.
 158 TEST(IsIdenticalToTest, DifferentDefs) {
 159   auto MF = createMachineFunction();
 160
 161   unsigned short NumOps = 2;
 162   unsigned char NumDefs = 1;
 163   MCOperandInfo OpInfo[] = {
 164       {0, 0, MCOI::OPERAND_REGISTER, 0},
 165       {0, 1 << MCOI::OptionalDef, MCOI::OPERAND_REGISTER, 0}};
 166   MCInstrDesc MCID = {
 167       0, NumOps,  NumDefs, 0,      0, 1ULL << MCID::HasOptionalDef,
 168       0, nullptr, nullptr, OpInfo, 0, nullptr};
 169
 170   // Create two MIs with different virtual reg defs and the same uses.
 171   unsigned VirtualDef1 = -42; // The value doesn't matter, but the sign does.
 172   unsigned VirtualDef2 = -43;
 173   unsigned VirtualUse = -44;
 174
 175   auto MI1 = MF->CreateMachineInstr(MCID, DebugLoc());
 176   MI1->addOperand(*MF, MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
 177   MI1->addOperand(*MF, MachineOperand::CreateReg(VirtualUse, /*isDef*/ false));
 178
 179   auto MI2 = MF->CreateMachineInstr(MCID, DebugLoc());
 180   MI2->addOperand(*MF, MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
 181   MI2->addOperand(*MF, MachineOperand::CreateReg(VirtualUse, /*isDef*/ false));
 182
 183   // Check that they are identical when we ignore virtual register defs, but not
 184   // when we check defs.
 185   ASSERT_FALSE(MI1->isIdenticalTo(*MI2, MachineInstr::CheckDefs));
 186   ASSERT_FALSE(MI2->isIdenticalTo(*MI1, MachineInstr::CheckDefs));
 187
 188   ASSERT_TRUE(MI1->isIdenticalTo(*MI2, MachineInstr::IgnoreVRegDefs));
 189   ASSERT_TRUE(MI2->isIdenticalTo(*MI1, MachineInstr::IgnoreVRegDefs));
 190
 191   // Create two MIs with different virtual reg defs, and a def or use of a
 192   // sentinel register.
 193   unsigned SentinelReg = 0;
 194
 195   auto MI3 = MF->CreateMachineInstr(MCID, DebugLoc());
 196   MI3->addOperand(*MF, MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
 197   MI3->addOperand(*MF, MachineOperand::CreateReg(SentinelReg, /*isDef*/ true));
 198
 199   auto MI4 = MF->CreateMachineInstr(MCID, DebugLoc());
 200   MI4->addOperand(*MF, MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
 201   MI4->addOperand(*MF, MachineOperand::CreateReg(SentinelReg, /*isDef*/ false));
 202
 203   // Check that they are never identical.
 204   ASSERT_FALSE(MI3->isIdenticalTo(*MI4, MachineInstr::CheckDefs));
 205   ASSERT_FALSE(MI4->isIdenticalTo(*MI3, MachineInstr::CheckDefs));
 206
 207   ASSERT_FALSE(MI3->isIdenticalTo(*MI4, MachineInstr::IgnoreVRegDefs));
 208   ASSERT_FALSE(MI4->isIdenticalTo(*MI3, MachineInstr::IgnoreVRegDefs));
 209 }
 210
 211 // Check that MachineInstrExpressionTrait::isEqual is symmetric and in sync with
 212 // MachineInstrExpressionTrait::getHashValue
 213 void checkHashAndIsEqualMatch(MachineInstr *MI1, MachineInstr *MI2) {
 214   bool IsEqual1 = MachineInstrExpressionTrait::isEqual(MI1, MI2);
 215   bool IsEqual2 = MachineInstrExpressionTrait::isEqual(MI2, MI1);
 216
 217   ASSERT_EQ(IsEqual1, IsEqual2);
 218
 219   auto Hash1 = MachineInstrExpressionTrait::getHashValue(MI1);
 220   auto Hash2 = MachineInstrExpressionTrait::getHashValue(MI2);
 221
 222   ASSERT_EQ(IsEqual1, Hash1 == Hash2);
 223 }
 224
 225 // This test makes sure that MachineInstrExpressionTraits::isEqual is in sync
 226 // with MachineInstrExpressionTraits::getHashValue.
 227 TEST(MachineInstrExpressionTraitTest, IsEqualAgreesWithGetHashValue) {
 228   auto MF = createMachineFunction();
 229
 230   unsigned short NumOps = 2;
 231   unsigned char NumDefs = 1;
 232   MCOperandInfo OpInfo[] = {
 233       {0, 0, MCOI::OPERAND_REGISTER, 0},
 234       {0, 1 << MCOI::OptionalDef, MCOI::OPERAND_REGISTER, 0}};
 235   MCInstrDesc MCID = {
 236       0, NumOps,  NumDefs, 0,      0, 1ULL << MCID::HasOptionalDef,
 237       0, nullptr, nullptr, OpInfo, 0, nullptr};
 238
 239   // Define a series of instructions with different kinds of operands and make
 240   // sure that the hash function is consistent with isEqual for various
 241   // combinations of them.
 242   unsigned VirtualDef1 = -42;
 243   unsigned VirtualDef2 = -43;
 244   unsigned VirtualReg = -44;
 245   unsigned SentinelReg = 0;
 246   unsigned PhysicalReg = 45;
 247
 248   auto VD1VU = MF->CreateMachineInstr(MCID, DebugLoc());
 249   VD1VU->addOperand(*MF,
 250                     MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
 251   VD1VU->addOperand(*MF,
 252                     MachineOperand::CreateReg(VirtualReg, /*isDef*/ false));
 253
 254   auto VD2VU = MF->CreateMachineInstr(MCID, DebugLoc());
 255   VD2VU->addOperand(*MF,
 256                     MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
 257   VD2VU->addOperand(*MF,
 258                     MachineOperand::CreateReg(VirtualReg, /*isDef*/ false));
 259
 260   auto VD1SU = MF->CreateMachineInstr(MCID, DebugLoc());
 261   VD1SU->addOperand(*MF,
 262                     MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
 263   VD1SU->addOperand(*MF,
 264                     MachineOperand::CreateReg(SentinelReg, /*isDef*/ false));
 265
 266   auto VD1SD = MF->CreateMachineInstr(MCID, DebugLoc());
 267   VD1SD->addOperand(*MF,
 268                     MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
 269   VD1SD->addOperand(*MF,
 270                     MachineOperand::CreateReg(SentinelReg, /*isDef*/ true));
 271
 272   auto VD2PU = MF->CreateMachineInstr(MCID, DebugLoc());
 273   VD2PU->addOperand(*MF,
 274                     MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
 275   VD2PU->addOperand(*MF,
 276                     MachineOperand::CreateReg(PhysicalReg, /*isDef*/ false));
 277
 278   auto VD2PD = MF->CreateMachineInstr(MCID, DebugLoc());
 279   VD2PD->addOperand(*MF,
 280                     MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
 281   VD2PD->addOperand(*MF,
 282                     MachineOperand::CreateReg(PhysicalReg, /*isDef*/ true));
 283
 284   checkHashAndIsEqualMatch(VD1VU, VD2VU);
 285   checkHashAndIsEqualMatch(VD1VU, VD1SU);
 286   checkHashAndIsEqualMatch(VD1VU, VD1SD);
 287   checkHashAndIsEqualMatch(VD1VU, VD2PU);
 288   checkHashAndIsEqualMatch(VD1VU, VD2PD);
 289
 290   checkHashAndIsEqualMatch(VD2VU, VD1SU);
 291   checkHashAndIsEqualMatch(VD2VU, VD1SD);
 292   checkHashAndIsEqualMatch(VD2VU, VD2PU);
 293   checkHashAndIsEqualMatch(VD2VU, VD2PD);
 294
 295   checkHashAndIsEqualMatch(VD1SU, VD1SD);
 296   checkHashAndIsEqualMatch(VD1SU, VD2PU);
 297   checkHashAndIsEqualMatch(VD1SU, VD2PD);
 298
 299   checkHashAndIsEqualMatch(VD1SD, VD2PU);
 300   checkHashAndIsEqualMatch(VD1SD, VD2PD);
 301
 302   checkHashAndIsEqualMatch(VD2PU, VD2PD);
 303 }
 304
 305 TEST(MachineInstrPrintingTest, DebugLocPrinting) {
 306   auto MF = createMachineFunction();
 307
 308   MCOperandInfo OpInfo{0, 0, MCOI::OPERAND_REGISTER, 0};
 309   MCInstrDesc MCID = {0, 1,       1,       0,       0, 0,
 310                       0, nullptr, nullptr, &OpInfo, 0, nullptr};
 311
 312   LLVMContext Ctx;
 313   DIFile *DIF = DIFile::getDistinct(Ctx, "filename", "");
 314   DISubprogram *DIS = DISubprogram::getDistinct(
 315       Ctx, nullptr, "", "", DIF, 0, nullptr, 0, nullptr, 0, 0, DINode::FlagZero,
 316       DISubprogram::SPFlagZero, nullptr);
 317   DILocation *DIL = DILocation::get(Ctx, 1, 5, DIS);
 318   DebugLoc DL(DIL);
 319   MachineInstr *MI = MF->CreateMachineInstr(MCID, DL);
 320   MI->addOperand(*MF, MachineOperand::CreateReg(0, /*isDef*/ true));
 321
 322   std::string str;
 323   raw_string_ostream OS(str);
 324   MI->print(OS, /*IsStandalone*/true, /*SkipOpers*/false, /*SkipDebugLoc*/false,
 325             /*AddNewLine*/false);
 326   ASSERT_TRUE(
 327       StringRef(OS.str()).startswith("$noreg = UNKNOWN debug-location "));
 328   ASSERT_TRUE(
 329       StringRef(OS.str()).endswith("filename:1:5"));
 330 }
 331
 332 TEST(MachineInstrSpan, DistanceBegin) {
 333   auto MF = createMachineFunction();
 334   auto MBB = MF->CreateMachineBasicBlock();
 335
 336   MCInstrDesc MCID = {0, 0,       0,       0,       0, 0,
 337                       0, nullptr, nullptr, nullptr, 0, nullptr};
 338
 339   auto MII = MBB->begin();
 340   MachineInstrSpan MIS(MII, MBB);
 341   ASSERT_TRUE(MIS.empty());
 342
 343   auto MI = MF->CreateMachineInstr(MCID, DebugLoc());
 344   MBB->insert(MII, MI);
 345   ASSERT_TRUE(std::distance(MIS.begin(), MII) == 1);
 346 }
 347
 348 TEST(MachineInstrSpan, DistanceEnd) {
 349   auto MF = createMachineFunction();
 350   auto MBB = MF->CreateMachineBasicBlock();
 351
 352   MCInstrDesc MCID = {0, 0,       0,       0,       0, 0,
 353                       0, nullptr, nullptr, nullptr, 0, nullptr};
 354
 355   auto MII = MBB->end();
 356   MachineInstrSpan MIS(MII, MBB);
 357   ASSERT_TRUE(MIS.empty());
 358
 359   auto MI = MF->CreateMachineInstr(MCID, DebugLoc());
 360   MBB->insert(MII, MI);
 361   ASSERT_TRUE(std::distance(MIS.begin(), MII) == 1);
 362 }
 363
 364 static_assert(is_trivially_copyable<MCOperand>::value, "trivially copyable");
 365
 366 } // end namespace